bluuebunny/crossref_metadata_2025 huggingface dataset:
Uniform Forward-modeling Analysis of Ultracool Dwarfs. III. Late-M and L Dwarfs in Young Moving Groups, the Pleiades, and the Hyades
Authors: Hurt Spencer A. , Liu Michael C. , Zhang Zhoujian , Phillips Mark , Allers Katelyn N. , Deacon Niall R. , Aller Kimberly M. , Best William M. J.
Published: January 2024

We present a uniform forward-modeling analysis of 90 late-M and L dwarfs in nearby young (∼10–200 Myr) moving groups, the Pleiades, and the Hyades using low-resolution (R ≈ 150) near-infrared (0.9–2.4 μm) spectra and the BT-Settl model atmospheres. We derive the objects’ effective temperatures, surface gravities, radii, and masses by comparing our spectra to the models using a Bayesian framework with nested sampling and calculate the same parameters using evolutionary models. Assuming the evolutionary-based parameters are more robust, our spectroscopically inferred parameters from BT-Settl exhibit two types of systematic behavior for objects near the M-L spectral type boundary. Several objects are clustered around T
eff ≈ 1800 K and

log
g
≈
5.5

dex, implying impossibly large masses (150–1400 M
Jup), while others are clustered around T
eff ≳ 3000 K and

log
g
≲
3.0

dex, implying unphysically low masses and unreasonably young ages. We find the fitted BT-Settl model spectra tend to overpredict the peak J- and H-band flux for objects located near the M-L boundary, suggesting the dust content included in the model atmospheres is insufficient to match the observations. By adding an interstellar medium–like reddening law to the BT-Settl model spectra, we find the fits between models and observed spectra are greatly improved, with the largest reddening coefficients occurring at the M-L transition. This work delivers a systematic examination of the BT-Settl model atmospheres and constitutes the largest spectral analysis of benchmark late-M- and L-type brown dwarfs to date.
Investigation of Periodic Modulation Behaviors from Pulsar J2022+5154
Authors: Chen J. L. , Wen Z. G. , Wang Z. , Duan X. F. , He D. L. , Wang N. , Wang H. G. , Yuan J. P. , Huang L. , Lyu C. B. , Yuen R. , Yan W. M. , Wu Z. W. , Han W. , Xiang B. B. , Dong A. J.
Published: January 2024

We have carried out a detailed study of individual pulse emission from the pulsar J2022+5154 (B2021+51), observed at 2250 MHz using the Jiamusi 66 m radio telescope. We have investigated the modulations in single-pulse behavior using fluctuation spectral analysis, which shows the presence of two prominent periodicities, around 5 and 40 rotation periods, respectively. The shorter periodicity is associated with the phenomenon of subpulse drifting. In the absence of aliasing, the emission pattern is demonstrated to consist of eight subbeams, which rotate around the magnetic axis in about 45 periods. In addition to subpulse drifting, the pulsar also shows the presence of periodic amplitude modulation with a longer periodicity in the single-pulse sequence. The pulsar joins a select group that shows the presence of periodic phase-modulated drifting as well as amplitude-modulated drifting. This provides further evidence for the two phenomena being distinct from each other with different physical origins.
Recurrently Propagating Intensity Disturbances along Polar Plumes Observed in White Light and Extreme Ultraviolet
Authors: Cho Il-Hyun , Moon Yong-Jae , Lee Jin-Yi , An Junmo , Yu Dae Jung , Cho Kyung-Suk , Lee Harim , Lee Jae-Ok
Published: January 2024

We study properties of intensity disturbances along polar coronal rays that are associated with plumes below. For this, we draw azimuth–time images of extreme ultraviolet (EUV) emission of 171 Å band observed by the SDO/AIA and white light (WL) observed by the SOHO/LASCO C2 in 2020 July. From the azimuth–time image, we define two tracks in which the EUV intensities were recurrently enhanced during two weeks. The two EUV tracks are rooted at 78.°8 and 81.°4 latitudes, but their projected azimuth angles are changed with time as the Sun rotates. Coherent WL tracks at different altitudes are determined by scaling the azimuth angles of the EUV tracks, accounting for the effect of inclination of coronal rays. From this, we construct time–distance images of WL intensities along WL tracks, whose projected azimuth angle changes along time and altitude, but the intensities are correlated with the EUV intensities measured below. The time–distance images of WL show repeated and inclined intensity features. The propagation speeds in the altitude range 2.3–6 solar radii are calculated to be 159 ± 8 km s−1 and 300 ± 24 km s−1. The EUV and WL intensities are found to be coherent at 1–2 day periods. It is also found that dynamic burst events along the EUV track are responsible for the enhanced emission. We conclude that the variation of the WL intensity along the polar coronal rays is related with the evolution of the EUV intensity below.
Modeling Solar Oscillation Power Spectra. III. Spatiotemporal Spectra of Solar Granulation Velocity Field as Seen in HMI Velocity Measurements
Authors: Vorontsov Sergei V. , Jefferies Stuart M. , Larson Timothy P.
Published: January 2024

We suggest a physically motivated model of the uncorrelated background, which can be used to improve the accuracy of helioseismic frequency measurements when the background contributes significantly to the formation of spectral lines of acoustic resonances. The basic assumption of our model is that the correlation length of the convective motions is small compared with the horizontal wavelength R
⊙/ℓ of the observations, where ℓ is the degree of the spherical harmonic Y

ℓ
m
(θ, φ). When applied to solar power spectra at frequencies below acoustic resonances, the model reveals a distinct sensitivity to solar rotation: advection of the convective velocity pattern brings spatial correlations in the apparent stochastic velocity field (temporal correlations in the corotating frame induce spatial correlations in the inertial frame). The induced spatiotemporal correlations manifest themselves as an antisymmetric component in the dependence of the convective noise power on azimuthal order m, which allows us to address the solar differential rotation. With 360 days of data obtained by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, we measure three components of the rotation rate as a function of latitude using only ℓ = 300. This result indicates that the model suggests a new way of measuring solar subsurface rotation. This approach can complement traditional measurements based on correlation tracking.
Polarized X-Rays Detected from the Anomalous X-Ray Pulsar 1E 2259+586
Authors: Peng Han-Long , Ge Ming-Yu , Weng Shan-Shan , Zhao Qing-Chang , Ye Wen-Tao , Zhang Liang , Qi Li-Qiang , Tuo You-Li
Published: January 2024

Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) are believed to be associated with magnetars, which have extremely strong magnetic fields. Recently, with the operation of the Imaging X-ray Polarimetry Explorer (IXPE), the polarization information of two AXPs and one SGR have been investigated. In this work, we report the observational results of the fourth magnetar, 1E 2259+586, with IXPE, and perform a joint analysis with observations from Neutron Star Interior Composition Explorer. We find that the emission from 1E 2259+586 is linearly polarized, with a polarization degree (5.3% ± 1.3%) and a polarization angle −77° ± 7° in the 2–8 keV energy range. Additionally, both the polarization degree and polarization angle exhibit variability with the pulse phase, and there is a hint of anticorrelation between the polarization degree and the flux, which is similar to AXP 1RXS J170849.0-400910. The phase-dependent polarization angle displays a sinusoidal profile and can be well fitted with the rotating vector model, indicating that the magnetic dipole field dominated the magnetic structure of the pulsar, and the variation in the polarization angle was modulated by the pulsar’s rotation.
Clouds and Clarity: Revisiting Atmospheric Feature Trends in Neptune-size Exoplanets
Authors: Brande Jonathan , Crossfield Ian J. M. , Kreidberg Laura , Morley Caroline V. , Barman Travis , Benneke Björn , Christiansen Jessie L. , Dragomir Diana , Fortney Jonathan J. , Greene Thomas P. , Hardegree-Ullman Kevin K. , Howard Andrew W. , Knutson Heather A. , Lothringer Joshua D. , Mikal-Evans Thomas
Published: January 2024

Over the last decade, precise exoplanet transmission spectroscopy has revealed the atmospheres of dozens of exoplanets, driven largely by observatories like the Hubble Space Telescope. One major discovery has been the ubiquity of atmospheric aerosols, often blocking access to exoplanet chemical inventories. Tentative trends have been identified, showing that the clarity of planetary atmospheres may depend on equilibrium temperature. Previous work has often grouped dissimilar planets together in order to increase the statistical power of any trends, but it remains unclear from observed transmission spectra whether these planets exhibit the same atmospheric physics and chemistry. We present a reanalysis of a smaller, more physically similar sample of 15 exo-Neptune transmission spectra across a wide range of temperatures (200–1000 K). Using condensation cloud and hydrocarbon haze models, we find that the exo-Neptune population is best described by low cloud sedimentation efficiency (f
sed ∼ 0.1) and high metallicity (100 × solar). There is an intrinsic scatter of ∼0.5 scale height, perhaps evidence of stochasticity in these planets’ formation processes. Observers should expect significant attenuation in transmission spectra of Neptune-size exoplanets, up to 6 scale heights for equilibrium temperatures between 500 and 800 K. With JWST's greater wavelength sensitivity, colder (<500 K) planets should be high-priority targets given their clearer atmospheres, and the need to distinguish between the “super-puffs” and more typical gas-dominated planets.
L’évolution de l’intuition collective dans une équipe de football en formation : une étude longitudinale à partir d’une méthode mixte pour examiner les relations entre la perception individuelle d’indices pertinents et les contenus cognitifs partagés entre coéquipiers
Authors: Kerivel Thibault , Fontaine Tanguy , Dugény Sylvain , Vacher Philippe , Vacher Philippe , Kermarrec Gilles , Bossard Cyril
Published: January 2024

Dans la perspective de mieux comprendre le phénomène de l’intuition collective en football de haut niveau, cette étude vise à montrer, par une méthode mixte, les liens qui se tissent au cours du temps entre les indices pertinents perçus à l’échelle individuelle et les contenus cognitifs partagés entre équipiers. Cette étude de cas longitudinale a été réalisée avec 8 joueurs de football professionnel, pendant 10 mois de formation. Elle repose sur une méthode mixte nécessitant la transformation et l’intégration de données qualitatives en données quantitatives. Les données qualitatives sont obtenues à partir d’entretiens d’autoconfrontation répétés sur les 10 mois. Après transformation des données, un traitement statistique a été appliqué (corrélations pour mesures répétées). Les résultats montrent que des corrélations fortes se sont établies au cours du temps entre les indices pertinents perçus et certains contenus cognitifs partagés par les joueurs en situation : indices partagés, buts partagés, attentes partagées et jugements partagés. Les résultats sont discutés au regard des apports théoriques et méthodologiques de l’étude.
Three new soft separation axioms in soft topological spaces
Authors: Abuzaid Dina , Al Ghour Samer
Published: January 2024

Soft $ \omega $-almost-regularity, soft $ \omega $ -semi-regularity, and soft $ \omega $-$ T_{2\frac{1}{2}} $ as three novel soft separation axioms are introduced. It is demonstrated that soft $ \omega $ -almost-regularity is strictly between "soft regularity" and "soft almost-regularity"; soft $ \omega $-$ T_{2\frac{1}{2}} $ is strictly between "soft $ T_{2\frac{1}{2}} $" and "soft $ T_{2} $", and soft $ \omega $ -semi-regularity is a weaker form of both "soft semi-regularity" and "soft $ \omega $-regularity". Several sufficient conditions for the equivalence between these new three notions and some of their relevant ones are given. Many characterizations of soft $ \omega $-almost-regularity are obtained, and a decomposition theorem of soft regularity by means of "soft $ \omega $ -semi-regularity" and "soft $ \omega $-almost-regularity" is obtained. Furthermore, it is shown that soft $ \omega $-almost-regularity is heritable for specific kinds of soft subspaces. It is also proved that the soft product of two soft $ \omega $-almost regular soft topological spaces is soft $ \omega $-almost regular. In addition, the connections between our three new conceptions and their topological counterpart topological spaces are discussed.
Thirty Years of Digital Technologies in the Field of Cultural Heritage
Authors: Dogruer Fatma Sezin
Published: January 2024

Digital technologies promoted innovation and proposed unprecedented opportunities to the sectors, one of which is cultural heritage. There are many benefits of digitization such as rapid access of data, cost-effectiveness according to benefit and loss assessment in a long term, and rapid identification of cultural heritage and risks. This study is the comprehensive bibliometric analysis that ensures statistical and all-embracing understanding in the digital technologies in cultural heritage literature, which was carried out in Web of Science between 1993 and 2022. The study is expected to spur scholars to perform more studies on digital technologies in cultural heritage. The analysis embodied 1826 publications written by 200 authors from 98 countries. Italy produced 24.20% of the world's publications on digital technologies in cultural heritage, which has the highest number of publications with 442 documents. The most used keywords in this literature are cultural heritage, virtual reality, and augmented reality.
Intensive Winter Culture of Chondrostoma nasus (Linnaeus, 1758) and Vimba vimba (Linnaeus, 1758) for Spring Restocking
Authors: Lepic Pavel , Blecha Miroslav , Kozak Pavel
Published: January 2024

The aim of this study was to compare the grow performance of two rheofilic fish species at different water temperatures (WT) under recirculation aquaculture system (RAS) conditions. Two six-month experiments were conducted during two consecutive winter seasons with the five-month-old nase Chondrostoma nasus (Linnaeus, 1758) and vimba bream Vimba vimba (Linnaeus, 1758) which had been trained on pellet feed and acclimated to four different temperatures. The three experimental groups were reared in closed separate RAS systems with the WT about 15°C, 18°C and 21°C respectively together with a fourth controlled group which were kept in a flow through system simulating ambient outside conditions at an average of approximately 4°C. All monitored parameters, total length (TL), (BW) body weight, specific growth rate (SGR) and food conversion ratio (FCR) were significantly greater with increasing of temperature in all groups for both fish. The nase total length gained 73.37±3.82, 94.11±5.58, 108.68±7.07 and 128.52±7.64 mm and body weight 2.85±0.47, 6.14±1.20, 9.26±2.14 and 16.71±3.46 g in 4, 15, 18 and 21°C, respectively. The same pattern was observed in vimba bream (TL 58.32±2.71, 69.33±6.68, 91.28±7.48 and 102.16±7.80 mm and BW 1.57±0.24, 2.71±0.50, 6.81±1.96 and 8.88±2.52 g).
Zhang Dongsun’s Encounters with “Logicism”
Authors: VRHOVSKI Jan
Published: January 2024

The article surveys the early work of Zhang Dongsun on topics like logicism of Bertrand Russell and scientific philosophy, which aimed to criticise its foundations and replace them with a Neo-Kantian alternative. It tries to show how a series of Zhang’s articles from early 1920s, in which he sought to create a new “neutral” variety of logicism, can be used to better understand the intellectual foundations of the neovitalist “philosophy of life” of Zhang Junmai. By delving deeper into the underlying ideas and possible motivations behind Zhang’s philosophical endeavours from the early 1920s, the article argues for a different kind of understanding of the historical basis of humanism in modern Chinese philosophy. Moreover, it strives to show how the “science and the view on life” controverse as initiated by Zhang Junmai in 1923 might be rooted or at least related directly to a syncretistic ideal, to conjoin science and the view of life in a new kind of harmonistic outlook. Most importantly, the article will try to show how Zhang Dongsun’s critical engagement with Russell’s philosophy, modern logic and physical science could be understood as the theoretical nucleus of the so-called “view on life” philosophy, not only in the context of the 1923 controverse but possibly the entire Republican Period. Due to the limited space, the article does not offer a concise introduction Zhang’s life and philosophy, but instead provides a focused discussion of particular fragments of his work from the early 1920s.
Cultural Reflections on the Great and Originating Period
Authors: ZHAO Jingang
Published: January 2024

Since the 1980s, Chen Lai has been attempting to resolve the binary opposition between tradition and modernity. He has contemplated the position of tradition in modern society from the perspective of “multicultural structures”, emphasizing the continuity of traditions of value rationality. In an exceptional move, he has departed from monistic universality and established “poly-universalism” to rethink the mode of existence of universality. He argues that universality is not an exclusive mode in which one must select one universalism or another, but rather that each civilization contains inherent universality. While certain conditions are required to realize universality, one cannot comprehensively replace the universal values of one civilization with those of another. Based on this cultural view, and considering the relationship between the basic principles of Marxism and traditional Chinese culture, Chen upholds the essence of benevolence, promotes the new four virtues, and reflects on the value of traditional Confucian virtues in contemporary China.
Introduction: Towards a Communicative Encounter ‒ Traditional Chinese Philosophy in Contemporary Discourses
Authors: YUAN Ai , CHEN Bisheng
Published: January 2024

In this special issue, we present contemporary studies of traditional Chinese philosophy, born out of the challenges faced during the COVID-19 pandemic. The scholars who contributed to this volume sought to engage in a profound dialogue, a necessity during a time when the pandemic prevented in-person cross-border meetings. Though COVID-19 is now behind us, the impact it left on our world continues to resonate. This collection should be seen as a response to the concern that “the loss of memory and the possibility of intercultural dialogues ...will deal humanism a final, fatal blow” (Rošker 2023, 8). It encompasses a diverse array of systematic studies predominantly authored by scholars from mainland China.
Bone indices and body weight changes of ovariectomized rats treated with Marantodes pumilum var. Alata
Authors: Giaze Tijjani R. , Abubakar Bilyaminu , Aminu Nafiu , Sheidu Azeez R. , Umar Milicent L. , Mohamed Norazlina
Published: January 2024

Marantodes pumilim var. alata (MPva) is a popular female aphrodisiac and known source of phytoestrogens. It is traditionally used to manage postmenopausal crisis and preserve bone health in women. The study aims to investigate the effects of MPva on bone indices and bodyweight of post-menopausal rats. Thirty female Sprague-Dawley rats were divided into groups (n=6): Healthy control (Sham); ovariectomized control (OVXC); Estrogen treatment (ERT); plant leaf extract treatment (MPr) and plant root extract treatment (MPv) groups. All rats (except the Sham-operated group) were ovariectomized. After 2-weeks healing period, the ERT group was treated with 64.5 μg/kg estrogen while MPv and MPr groups received pre-determined optimal daily dose of MPva leaf and root extracts, respectively. Changes in bodyweight of rats were monitored through an eight-weeks treatment period after which rats were euthanized for testing of bone parameters. Both leaves and roots of MPva (20 mg/kg) were found to show optimal preservation of bone mineral density and mechanical strength. Untreated estrogen-deficient rats (OVXC) showed significant weight-gain when compared with the healthy control (Sham) (p<0.05). Treatment with MPva leaf and root extracts, similar to treatment with estrogen, significantly suppressed weight-gain observed in the estrogen-deficient (OVXC) group (p<0.05). In conclusion, treatment with MPva leaf and root extracts preserved bone strength. In addition, it suppressed weight gain in postmenopausal rats, an outcome that makes MPva more beneficial to postmenopausal women that may experience weight gain.
Synthesis, characterization and isothermal studies of Mg-Fe Layered hydroxide with bentonite clay for the removal of alizarin blue dye from aqueous solution
Authors: Shinkafi Isah Y. , Suraj Fatima G. , Yahaya Shamsuddeen , Adiya Zainab I. S. G. , Ibrahim Imrana , Aliyu Musa , Bature Hafsatu B. , Adamu Samira S. , Abba Zulyadaini Y. , Musa Yakubu
Published: January 2024

This research aimed to prepare and characterize Mg-Fe layered Hydroxide clay for removal of alizarin blue dye from aqueous media using batch adsorption technique. The Mg-Fe layered Hydroxide prepared was characterized by SEM, FT-IR and XRD before and after adsorption. The result obtained from SEM shows a large surface area before and a rough and filled surface after adsorption. The presence of OH, C=O and N-CH stretching at 3644 cm-1, 1771 cm-1 and 2884 cm-1 respectively was analyzed by FT-IR. It was verified that the crystalline structure was not altered during the pillaring process as evidenced by XRD. Various parameters such as initial dye concentration (10 – 50 mg/l), contact time (10 – 50 mins), adsorbent dose (0.1 – 0.5 g) and Temperature (30 – 70oC) were investigated. The experiments showed the following results; dye concentration decreased from 95.70% - 72.6%, contact time increased from 87.70% - 98.0% and adsorbent dose showed 87.7% - 92.3% removal respectively. The Adsorption isotherms of Freundlich, Langmuir, Temkin and Harkin’s-Jura Isotherms were used to observe the adsorption condition. Freundlich adsorption Isotherm fitted best with maximum removal of 6.97 mg/g and R2 value of 0.999. In this work, Mg-Fe layered hydroxide with bentonite clay which is low cost became effective adsorbent for the removal of Alizarin blue dye.
Cushy and Cheap Smart Health Monitoring System Incorporating a Ventilator
Authors: Okomba Nnamdi S. , Esan Adebimpe O. , Omodunbi Bolaji , Adedayo Sobowale A. , Adanigbo Opeyemi O.
Published: January 2024

The handiness of mercantile mechanical ventilators is highly limited in low-income countries due to high rate in the price of its  affordability. This factor affects the treatment of so many patients suffering from chronic respiratory syndrome. In this research, a low- cost and easy to use pressure ventilator coupled with a remote health monitoring system to assist the doctors check up on the patients is developed. There is need to maximize the availability of the ventilators in low-income countries at an affordable price tag. This system  was developed with the aid of an Arduino nano, ESP8266 based NodeMcu microcontroller, high pressure blower, pressure transducers,  humidity and temperature sensor. The developed system was evaluated and compared with existing one, using an actively breathing  patient simulator as it mimics through a range of respiratory diseases. In the end, we were able to design a low-cost smart health  monitoring system that incorporates ventilator and health vitals monitor. Our Design was implemented and verified to be working and  equally satisfying all the specified requirements.
Species Composition and Abundance of the Cichlid Fishes in Owalla Reservoir, Osun State, Nigeria
Authors: Kolawole Mustapha Abdur- Rahman , Adegoke Wahab Munir Karounwi , Siji Ajisebiola Babafemi , Adekilekun Kolawole Asiata
Published: January 2024

Fish production plays crucial roles in enhancing food security and alleviating poverty of many people in Nigeria. As demand for fish  increases steadily over the years, production becomes inadequate. One of the ways in which adequate fish production could be met is  adequate conservation efforts. This study was conducted with a view of providing a more recent catalogue and update of species  composition and abundance of cichlid fishes in Owalla reservoir. Sampling for cichlids fishes in the reservoir was done monthly for 24  weeks with the use of dugout canoe. Four experimental gillnets, each measuring 2 by 30 m, with various stretched mesh sizes (25.4, 38.1,  50.8 and 63.5 mm) were designed to sample various sizes of the fishes. Other sampling techniques adopted include the use of cast net,  fish traps and hook and line. The six species of cichlid fishes identified during study are Hemichromis fasciatus (SL=7.35±0.12 cm; mean  weight=15.58±9.01g), Sarotherodon galilaeus (SL=11.77±3.12 cm; mean weight=89.48±14.17 g), Oreochromis niloticus (SL=8.35±1.90 cm;  mean weight=36.11±10.02 g ), Tilapia zilli (SL=9.95±1.09 cm; mean weight=88.03±16.04 g ), Tilapia mariae (SL=9.83±1.07 cm; mean  weight=57.81±14.01 g ) and Tilapia dageti (SL=11.12.±2.01 cm; mean weight=85.30±20.01 g). The fish species were adequately  represented, well distributed and occurred frequently in both wet and dry seasons, though the occurrence was higher in the wet season.  The mean values of length and weight recorded for the fishes were small when compared with the values of cichlids from similar  Nigerian inland waters and was attributed to the indiscriminate use of gillnets with unregulated mesh sizes. Overfishing by the artisanal  fishermen could not be ruled out due to lack of regulations on the reservoir. Therefore, regular qualitative and quantitative information  on cichlid fishes in the reservoir is necessary for enhancement of management and appraisal of the fisheries potential of the reservoir  becomes essential.
Magnetic Structural Depth Classification Using Center for Exploration Targeting And 3D Euler Deconvolution: A Case Study of Shanga (Sheet 96) North West, Nigeria
Authors: Tawey Mam Daniel , Ehinlaiye Ayamezimi Oziofu , Adesoji Ibrahim Abdulrazaq
Published: January 2024

The present study involved the use of 3D Euler deconvolution to classify the depth of occurrences of magnetic structures as explicated and elucidated by the Centre for Exploration Targeting Plug-in (CET). To achieve this aim, the residual magnetic anomaly was first reduced to the equator (RTE) to centre the anomaly peaks directly above each causative source. After that, the RTE data was imputed into the CET plug-in, which is an extension of Oasis Montaj, to delineate structures that occur within the area. A 3D Euler deconvolution map with a structural index of one (SI = 1) that identified faults, dykes, and horizontal bodies was created using the RTE data. The Euler deconvolution depths were classified for depths that are <150 m, between 150 m and 300 m, 300 m and 450 m, and > 450 m. The CET delineated structures were superimposed over the 3D Euler deconvolution map with SI = 1, and most of the CET structures coincided with the structures from the Euler deconvolution map with SI = 1. Since Euler solutions are classified based on depth, the Euler structural map was used to classify the CET delineated structures based on their depths. The Euler structural map was imported into ArcGIS version 10.8 to digitize the structures based on their corresponding depth as displayed on the 3D Euler deconvolution map of SI = 1. After digitizing the Euler map with a structural index equal to one (SI = 1) with classified depth, a new structural map was then produced depicting each structure delineated with the CET based on their respective depth.
Assessment of Some Toxic Heavy Metals in Rice and Beans Sold in Benin City, Nigeria
Authors: Ovonramwen O.B. , Awulor C.F. , Ukpebor J.E. , Ukpebor E.E.
Published: January 2024

Rice and beans are staple foods for more than 50% of the world's population. They are prone to heavy metal contamination, with the  global rise in heavy metal pollution, which causes harm and danger to the ecosystem and puts people and other living things in major  health problems. This study aimed to determine the level of some heavy metals in local and foreign rice and white and brown bean  samples obtained from an open market in Benin City. The samples were prepared and analysed using a standard method with the aid of  an atomic absorption spectrophotometer (A.A.S.). The results of the analysis show the levels of heavy metals in the beans and rice ranged  from 0.013–0.067 mg/kg for Pb, 0.02-0.043 mg/kg for Cr, 0.003-0.367 mg/kg for Mn, 0.263–1.017 mg/kg for Zn, 0.30–0.933 mg/kg  for Fe, and 0.01–0.023 mg/kg for Cu, with Cd being the only metal below the detection limit. Statistical analysis using a t-test showed that  there was no significant difference between the levels of the selected heavy metals analysed among the bean samples and those  analysed among the rice samples. If these heavy metals are used as benchmarks for measuring the product's quality, local rice would be  considered to be of higher quality than foreign rice, according to statistical analysis using a correlation matrix that showed a nearly  identical heavy metal composition between local and foreign rice. The concentration of all the metals studied was observed to be present  at tolerable levels lower than the maximum permissible limit as given by the World Health Organisation (WHO). Based on the research  findings, the rice and bean samples studied were safe for human consumption.
Curie Point Depth from Spectral Analysis of Magnetic Data in Potiskum and Environs, Yobe State, Nigeria
Authors: Ezekiel Kamureyina , Peter Yohanna
Published: January 2024

The area under investigation, is part of Chad basin of northeastern Nigeria, located between latitudes 11o00´ to 12o00´N and Longitudes  11o30´ to 12o30´E, with the objective to discover more about the thermal structure of the crust in the area, a research was carried out over  Potiskum and surrounding regions in Yobe State, Nigeria to estimate the curie point depth, geothermal gradient, and heat flow using  spectrum analysis and empirical formula of aeromagnetic data. To acquire the regional and residual data, polynomial fitting was applied  to the high-resolution digital aeromagnetic data. In order to calculate the depth to the centroid and the depth to the top boundary, the  upward continued residual data was processed to produce the upward continued data, that was subjected to spectral analysis. The depth  to the centroid is between 10.50 and 11.50 kilometers, the depth to the top boundary is between 5.90 and 7.16 kilometers, the depth to  the Curie point is between 14.84 and 16.83 kilometers, the geothermal gradient is between 34.462 and 39.083 oCkm-1, and the heat flow  is between 86.135 and 97.707 mWm-2. The Curie point depth inferred from the study indicates that the crust is thinning due to thermal  upwhirling of magma and is moderately decreasing toward areas of volcanic activity that occurred in the area during the Tertiary Period.  The Geothermal gradient shows that the area is a moderate temperature zone, which could likely result in partial thermal maturation of  sediments and hence probable oil generation as time goes on with an increase in temperature. In the research area, the geothermal  gradient is proportional to the heat flow, whereas the connection between curie depth and heat flow is inversely linear. These findings  are in line with the geotectonic regime that is now in effect in the research area. However, this analysis shows that the heat flow that was  obtained from the study is sufficient to be utilized as a geothermal energy source.
On a class of four-step modified backward differentiation formula (MBDF) for solving second-order ordinary differential equations
Authors: Atsi Kaze , Tumba Pius , Suleiman Enoch
Published: January 2024

This research was conducted to study a class of four-step modified backward differentiation formula (MBDF) for solving second-order ordinary differential equations, with one super-future point. A block method was constructed for the solution of problems of second-order ordinary differential equations. Adopting a step-number, k=4, we obtained a number of discrete methods in block. The stability properties of the block method were investigated using Maple application. In order to ascertain its suitability, the method was tested on some initial valued problems of second-order ordinary differential equations. The numerical solutions of the problems were compared with the respective exact solutions and of other existing methods, and are presented in both tables and graphs.
Results on prime and semi-prime rings with skew and generalized reverse derivations
Authors: Hafsat Mohammed , Funmilola Balogun , Tasiu Abdullahi
Published: January 2024

For this study, R represents a semiprime ring or a prime ring, as the case may be. The ring R is said to be semiprime if for any a ∈ R, aRa = {0}, implies a = 0. R is a prime ring if aRb = {0}, implies a = 0 or b = 0, ∀ a, b ∈ R. By assuming that d is a skew derivation with an automorphism β: R→R associated with it, we prove some results on skew-derivations for semi-prime rings. In particular, we show that for a skew-derivation, if d(a)d(b) ± ab = 0, ∀ a, b ∈ R then d = 0. Also, by introducing new differential identities, we establish that a prime ring with a generalized reverse derivation defined on it is commutative.
Assessment of the health risk of some heavy metals in cabbage grown on dumpsite at Hanwa in Zaria, Kaduna State, Nigeria
Authors: Yashim Z. I. , Salaudeen L. A.
Published: January 2024

Pollution of soil with heavy metals can lead to high concentration of the metals in plants, consequently in animals and human body. Cadmium, Copper and Lead concentrations were determined in soil samples and cabbage (Brassica oleracea) grown on a dumpsite at Hanwa in Zaria, Nigeria. Both the soil and plant samples were digested using a mixture of Nitric acid and Perchloric acid (ratio 3:1). The metals concentrations in the samples were determined using Atomic Absorption Spectroscopy (AAS). Soil parameters like Particle Size, pH, Moisture Content, and Organic Matter were also evaluated using standard methods. The results indicated much higher concentrations of heavy metals in the soil than roots, stems and leaves of the analyzed cabbage sample. The Cd level in the plant samples ranged from 1.20 to 1.70mg/kg (site) and 0.80 to 1.00mg/kg (control). Concentration of Cu in the samples ranged from 15.50 to 35.90mg/kg (site) and 7.30 to 13.90mg/kg (control) and Pb: 19.40 to 42.70mg/kg (site) and 5.80 to 26.40mg/kg (control)were above the recommended limit by joint FAO/WHO. The Transfer Factor (TF) of the studied metals from soil to cabbage leaves were in the order of Cd (0.92) > Pb (0.58) > Cu (0.44).In this study, the Health Risk Index (HRI) for Pb (3.421) was found to be greater than 1, which indicates significant potential health risks. The high level of these heavy metals places the consumers of cabbages grown within the dumpsite area at health risk. Cultivation of vegetables on metal dumpsites should be discouraged as the soils are polluted with heavy metals.
Les déterminants de la réussite des initiatives exogènes de la diversification des moyens de subsistance des communautés de pêcheurs
Authors: Ranaivomanana Lala , Mara Edouard R. , Mahafina Jamal A.
Published: January 2024

The study conducted in Madagascar explores on the diversification of livelihoods in Madagascar was carried out to identify the determining elements of the livelihood strategies of fishing communities and to bring out the relevant points of intervention to move the system towards sustainable livelihood strategies. The study was carried out in two stages: first, investigations were undertaken in three areas (Toliara-Sud, Ambaro Bay and Belo sur Tsiribihina) in order to assess the livelihood strategies of fishing communities following the theoretical framework advocated by Ashley and Carney (1999). Secondly, more in-depth investigations were carried out on four projects aimed at the sustainable livelihoods of fishing communities, to draw lessons from their implementation while taking into account the contexts in which they were carried out. The study of the diversification of livelihoods in fishing communities in Madagascar first made it possible to highlight the vulnerability of coastal communities. We are in the presence of a population that corresponds to the typology of the poor described by Dissou et al. (2000): generalized poverty at the level of the five forms of Capital according to the concept of "capability" mentioned by Sen (1985, Gondard-Delcroix and Rousseau 2004). We are also in the presence of a very vulnerable population due to its strong dependence on natural resources and a very low diversification of its means of subsistence. Also, the population's only recourse is to develop survival strategies to the detriment, as usual, of natural capital. Lessons learned from the implementation of the four projects reviewed highlight the importance of both entry points and the performance of exit plans. The entry points evoke the need for participation, the determinants of which turn out to be, first, the superposition of the immediate, often economic, needs of the population and the “deferred” needs for the sustainability of natural capital. Active and effective participation also happens to be dependent on respect for the power and decision-making structure actually in force at the local community level. The performance of exit plans depends on the degree of completion of the institutionalization of the structures supporting the participation of local communities. During the examination of the targeted projects, one notices in a notorious way, on the one hand, the quasi absence of an approach by typology which constitutes the base of the approach by the sustainable means of subsistence. On the other hand, it was also noted the failure of an appropriate monitoring-evaluation system which would have allowed any effective and efficient capitalization.
Exploring the potential of occupancy modelling using passive acoustics in Coua gigas and Coua coquereli
Authors: Jordan Celine , Markolf Matthias
Published: January 2024

In highly threatened habitats such as the dry deciduous forests of western Madagascar, it is essential to develop new approaches to detect population changes and evaluate conservation measures. Passive acoustic monitoring (PAM) is such a promising approach. This method has many advantages over conventional methods, such as time efficiency, money savings, and reduced wildlife disturbance. It is especially suitable for studying occupancy and activity patterns of vocalizing species such as birds. Our study analyzed data recorded with autonomous sound recorders in 2018 in Kirindy Forest for the territorial calls of Coua gigas and Coua coquereli. We modeled occupancy and detection probability for both species in the study area. We also examined activity patterns and found that the peak of vocal activity for Coua coquereli is at 700h and for Coua gigas at 1100h. To also test the value of PAM in relation to ecological factors we modeled occupancy and included logging status as a site covariate. We detected a positive influence of logging in occupancy of Coua gigas. Our study provides guidelines for future occupancy studies using PAM in the two coua species. We conclude that PAM will improve the ecological monitoring of soniferous animals in Madagascar.
Epidemiology and trends in the uptake of refractive error services in Harare, Zimbabwe: a hospital-based retrospective study
Authors: Kahoto Vimbainashe Evidence , Kwarteng Michael Agyemang , Afriyie Bismark Owusu- , Zaabaar Ebenezer , Kyei Samuel
Published: January 2024

AimThe study aimed to determine the epidemiology and evaluate the trends in the uptake of refractive error services in Harare. MethodsA clinic-based retrospective study at the Greenwood Park Eye Centre and its three subsidiaries was conducted from January 1, 2015 to December 31, 2020. Results12,216 patients’ records were retrieved, out of which 1074 (8.79%) had refractive error cases. The prevalence of visual impairment at presentation was 5.80% [95% CI: 5.39 – 6.23]. Among those with refractive error, the sample prevalence of visual impairment before correction was 41.30% [CI: 38.3 – 44.3, 95%], and 2.20% [95% CI: 1.4 – 3.3] after correction. There was inconsistency in the percentage utilization of refractive error services, with the highest being 42.60% in 2015. Refractive error types were related to age, employment position, and type of visual impairment prior to refractive error treatment. ConclusionThere was a low percentage of refractive error services uptake in urban Zimbabwe.
A rare case of Odontogenic Keratocyst in the Maxillary Sinus: diagnosis and management
Authors: Palem Sindhusha Reddy , Devarakonda Visalakshi , Navakoti Prasad , Pendyala Karuna Sree
Published: January 2024

Odontogenic keratocyst is a benign intraosseous lesion of odontogenic origin which is characterized by its aggressive nature. It is usually present in the mandibular posterior area, although it can also be found in the maxilla, particularly in the canine region. We discuss a unique example of OKC in the maxillary sinus involving the 27&28 region. Due to comparable clinical signs, this lesion is more prone to be mistaken for other lesions of the maxillary sinus, such as sinusitis or polyps. On the other side, this benign disease has the potential to develop into Ameloblastoma or squamous cell carcinoma. A favorable prognosis thus depends on early identification, precise diagnosis, appropriate treatment, and follow-ups.
Investigation of natural radioactivity in soil of selected hospitals in Imo State, Nigeria
Authors: Okwor Ibeabuchi E. , Akulor Chidi E. , Ukewuihe Udoka M.
Published: January 2024

We measured the terrestrial activity contents, radiation doses; hazard indices and excessive lifetime cancer risk (ELCR) from primordial radionuclides (226Ra, 232Th and 40K) in 50 soil samples collected from the five selected hospitals within Imo State, Nigeria. Radioactivity measurements were carried out by the method of gamma-ray spectrometry with thallium doped sodium iodide [NaI(Tl)] detector. The mean activity values obtained for the radionuclides 226Ra, 232Th and 40K (respectively) in Federal Medical Centre, Owerri (FMC); General Hospital, Umuguma, Owerri West, (GHW); Neuroscience Hospital, Ohaji Egbema (NHO); St. Joseph Hospital, Okigwe (SJH); Imo State University Teaching Hospital, Orlu (IMSUTH) are: 20.56±4.73, 14.96±3.42 and 105.65±31.40 Bqkg-1; 11.77±3.03, 17.45±4.20 and 63.67±18.44 Bqkg-1; 17.97±4.65,10.02±2.18 and 190.43±42.83 Bqkg-1; 11.36±3.71, 17.39±4.46 and 76.29±25.08 Bqkg-1; and 11.84±3.64, 4.89±2.25 and 165.18±58.41 Bqkg-1 respectively. These values were below the worldwide average values: 32 Bqkg-1 for 226Ra, 45 Bqkg-1 for 232Th, and 412 Bqkg-1 for 40K as documented by UNSCEAR (2000). 40K recorded the highest mean activity compared to 226Ra and 232Th in the studied soil samples. Radium equivalent activity (Raeq), absorbed gamma dose rate (Dr), annual effective dose equivalent (AEDE), external hazard index (Hex), gamma representative index (Ιϒr) and annual gonadal dose equivalent (AGDE), were calculated to quantify the radiation risk to the public from exposure to 226Ra, 232Th and 40K in the studied samples. In addition, excess lifetime cancer risk (ELCR) was also accessed. The mean computed values of the excess lifetime cancer risk for FMC, GHW, NHO, SJH and IMSUTH are 0.08±0.03, 0.09±0.15, 0.10±0.2, 0.10±0.03 and 0.07±0.02 respectively. The mean values of these hazard parameters were within the acceptable safety limits provided for human safety and environmental protection.
Knowledge, perception and practice of antimicrobial stewardship among doctors in public secondary healthcare facilities in Kaduna State, Nigeria: A pilot survey
Authors: Joshua I.A. , Yazid Y. , Agbana R.D. , Sabitu K. , Sufiyan M.B. , Bature S.B. , Banda J.M.
Published: January 2024

Infectious diseases remain a major cause of morbidity and mortality especially in Africa, Nigeria inclusive. Antimicrobials are used to treat microbes; hence their rational use is very crucial. This study assessed knowledge, perception and practice of antimicrobial stewardship (AMS) among doctors in public secondary healthcare facilities in Kaduna State. A cross-sectional descriptive study was conducted from March to May 2020 among doctors using a self-administered questionnaire. A total of sixty doctors were selected using a multi-stage sampling technique. Data was analyzed using SPSS version 23 and results were presented using tables and charts. Chi square and Fisher’s exact tests were used to test for association between categorical variables where appropriate. The level of statistical significance was set at p-value of <0.05. The median age of the participants was 33.5 years. Over half (52.6%) of the respondents were unaware of the term AMS; 29.8% had good knowledge of AMS and 87.7% had positive perception towards AMS. Three out of ten (30.0%) respondents had good practice of AMS. There were no statistically significant associations between age, sex, educational qualification and department of the respondents and the practice of AMS. The respondents’ knowledge of AMS was poor and majority had positive perception, but the practice among them was poor. There is need for training and retraining of doctors on AMS by the State Ministry of Health and their professional associations in order to enhance knowledge and practice on AMS.
Investigation of the mycoflora of deteriorating tomatoes (Solanum lycopersicum Mill.) sold in Lokoja markets, Kogi State, Nigeria
Authors: Okolo Esther , Abubakar Abdulsalam
Published: January 2024

The deterioration of tomatoes poses significant risks to public health as it can lead to the growth of fungi that produce harmful mycotoxins. This study focused on investigating the mycoflora associated with deteriorating tomatoes sold in selected Lokoja markets, Kogi State, Nigeria. A total of eighteen (18) samples, each containing three deteriorating tomatoes were randomly collected from six vendors in three different markets. Standard microbiological methods were employed to analyze the samples. The results revealed the presence of Aspergillus niger, Microsphaeropsis arundinis, Penicillium sp. and Rhizopus arrhizus as the predominant fungi in the deteriorating tomato samples. Samples from Adankolo market yielded the highest mean fungal load (4.63 × 106 CFU/g) and was significantly different (p≤0.05) from those of Old market (2.78 × 106 CFU/g) and Lokongoma market (2.67 × 106 CFU/g). Notably, A. niger had the highest occurrence (48.9 %) while R. arrhizus had the lowest occurrence (2.2 %). The presence of these fungal contaminants highlights the lack of fungi-free deteriorating tomatoes in Lokoja markets. The high occurrence of Aspergillus niger and the overall fungal load levels highlight the potential health risks associated with consuming these tomatoes. Consequently, the consumption of deteriorating tomatoes should be discouraged due to the potential health risks associated with mycotoxin production by these fungi. Strategies to mitigate fungal growth and spoilage of tomato in the markets as well as further research on mycotoxin production and health implications are fundamental for ensuring food safety and protecting public health.