bluuebunny/crossref_metadata_2025 huggingface dataset:
Embryonic stem cells maintain high origin activity and slow forks to coordinate replication with cell cycle progression
Authors: Kurashima Kiminori , Kamikawa Yasunao , Tsubouchi Tomomi
Published: July 2024

Embryonic stem (ES) cells are pluripotent stem cells that can produce all cell types of an organism. ES cells proliferate rapidly and are thought to experience high levels of intrinsic replication stress. Here, by investigating replication fork dynamics in substages of S phase, we show that mammalian pluripotent stem cells maintain a slow fork speed and high active origin density throughout the S phase, with little sign of fork pausing. In contrast, the fork speed of non-pluripotent cells is slow at the beginning of S phase, accompanied by increased fork pausing, but thereafter fork pausing rates decline and fork speed rates accelerate in an ATR-dependent manner. Thus, replication fork dynamics within the S phase are distinct between ES and non-ES cells. Nucleoside addition can accelerate fork speed and reduce origin density. However, this causes miscoordination between the completion of DNA replication and cell cycle progression, leading to genome instability. Our study indicates that fork slowing in the pluripotent stem cells is an integral aspect of DNA replication.
A pumpless liver-on-a-chip for drug hepatotoxicity analysis
Authors: Jiao Dian , Xie Lan , Xing Wanli
Published: July 2024

This study presents the development and validation of an innovative microfluidic liver-on-a-chip device utilizing gravity-driven perfusion for the evaluation of drug hepatotoxicity.
Oxalamide ligands with additional coordinating groups for Cu-catalyzed arylation of alcohols and phenols
Authors: Yao Xiantong , Yang Xin , Chen Fanghua , Chen Rui , Sun Maolin , Cheng Ruihua , Ma Yueyue , Ye Jinxing
Published: July 2024

A novel oxalamide ligand with additional coordinating groups was developed for the coupling of (hetero)aryl bromides with both alcohols and phenols.
A quick access to CF3-containing functionalized benzofuranyl, benzothiophene and indolyl heterocycles under catalyst-free conditions
Authors: Kazi Ayazoddin Aunoddin , Manjuladevi Nadimpalli , Kumar Salla Suresh , Sharma Anamika , Singh L Ravithej
Published: July 2024

2-BTP as a benign CF3 synthon, a catalyst-free one-pot synthetic protocol is presented for the preparation of trifluoromethyl containing benzofuran, indolin, and benzothiophene derivatives using readily available aromatic aldehydes and ketones.
Oxygen electrocatalysis-driven electrochemiluminescence by hierarchical carbon nanoflower-supported copper-modulated cobalt sulfide for cytosensing
Authors: Cao Yue , Gao Yan-Yan , Bao Qing-Yuan , Cao Yu , Zhu Jun-Jie , Zhou Yang
Published: July 2024

Copper/cobalt bimetallic sulfides dispersed on hierarchical carbon nanoflowers exhibit excellent oxygen electrocatalysis capacity to drive electrochemiluminescence for cytosensing.
A real time study of the coupled electrochemical and mechanical behaviors of the spinel cathodes in LIBs
Authors: Li Dawei , Jin Zhiyao , Jiang Hainan , He Yaolong , Yu Huijie
Published: July 2024

Three types of cathodes were chosen as the working cathode, and the coupled mechanical and electrochemical properties were analyzed to understand their degradation mechanism.
Ion current oscillation of polyelectrolyte modified micropipettes
Authors: Xiong Tianyi , Ma Wenjie , Yu Ping
Published: July 2024

Ion current oscillation of polyelectrolyte modified micropipettes in pH gradients was discovered and regulated. The periodic switch between the protonated/deprotonated state of modified micropipettes contributed to the spontaneous ICO observation.
A novel chemical purification method for accurate Sn isotope measurement by MC-ICP-MS
Authors: Qu Qinyuan , Liu Wengang , Zheng Wang , Chetelat Benjamin , Liu Qingchuan , Chen Jiubin
Published: July 2024

A novel two-step chromatographic separation procedure is developed for the Sn isotope chemical purification. With this method, both even and odd Sn isotope ratios can be precisely determined without double-spike correction.
Photoejection–recapture of the Ca2+ cation studied by time resolved spectroscopy and TDDFT calculations: the case study of an azacrown–iridium(iii) complex
Authors: Guerrin Clément , De Thieulloy Laure , Dubois Julien , Barois Clément , Perrier Aurélie , Leray Isabelle , Mongin Cedric , Aloise Stephane
Published: July 2024

The photophysical properties of an azacrown–iridium(iii) complex, designed to trap and photo-release Ca2+, are investigated with ultrafast spectroscopy and TDDFT calculations.
Reactivity study of 4-hydroxythiocoumarin: a novel synthetic route to fused chromono-thiophene and -thiopyran derivatives through solvent-dependent thio-Claisen rearrangement
Authors: Goswami Ujjwal Jyoti , Xalxo Anjela , Kusum  , Basumatary Mapleleaf , Soni Kaushik , Bhattacharyya Kalishankar , Khan Abu Taleb
Published: July 2024

The synthesis of fused chromono-thiophenes and -thiopyrans are achieved from 4-hydroxythiocoumarin derivatives utilising simple alkylation followed by [3,3]-sigmatropic rearrangement and subsequent solvent-dependent divergent ring closure reactions.
Shear thickening in suspensions of particles with dynamic brush layers
Authors: Kim Hojin , van der Naald Michael , Braaten Finn A. , Witten Thomas A. , Rowan Stuart J. , Jaeger Heinrich M.
Published: July 2024

Dynamic covalent bonds in suspensions serve as effective friction, leading to shear-thickening behavior. This behavior is similar to that of physically contacting particles but shows a distinct dependence on particle size.
I told you to stop: obscurin's role in epithelial cell migration
Authors: Shultz Kamrin D. , Al Anbari Yasmin F. , Wright Nathan T.
Published: July 2024

The giant cytoskeletal protein obscurin contains multiple cell signaling domains that influence cell migration. Here, we follow each of these pathways, examine how these pathways modulate epithelial cell migration, and discuss the cross-talk between these pathways. Specifically, obscurin uses its PH domain to inhibit phosphoinositide-3-kinase (PI3K)-dependent migration and its RhoGEF domain to activate RhoA and slow cell migration. While obscurin's effect on the PI3K pathway agrees with the literature, obscurin's effect on the RhoA pathway runs counter to most other RhoA effectors, whose activation tends to lead to enhanced motility. Obscurin also phosphorylates cadherins, and this may also influence cell motility. When taken together, obscurin's ability to modulate three independent cell migration pathways is likely why obscurin knockout cells experience enhanced epithelial to mesenchymal transition, and why obscurin is a frequently mutated gene in several types of cancer.
Prevailing Practices in Ototoxicity Monitoring in Individuals With Head and Neck Cancer Undergoing Radiotherapy and Chemoradiotherapy: A Scoping Review
Authors: Shankar Varsha , Seethapathy Jayashree , Srinivas Satish , Nandhan Raghu , Saravanam Prasanna Kumar
Published: July 2024

Purpose:

The aim of the current scoping review is to identify the studies reporting ototoxicity monitoring in individuals with head and neck cancer (HNC) undergoing radiation therapy and/or chemoradiation therapy across the world. The specific objectives were to identify and report the test protocol used, identify the most common timeline of follow-up, and identify barriers and facilitators influencing the implementation of the monitoring program.

Method:

A comprehensive search was conducted across six electronic databases, including PubMed, Embase, Web of Science, Scopus, Google Scholar, and ProQuest. The scoping review method adhered to relevant guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) and frameworks. The database search was carried out by two independent researchers, and studies were selected based on specific inclusion and exclusion criteria.

Results:

This scoping review identified 13 studies that fulfilled the inclusion criteria of this study. Only one study reported findings from the perspective of ototoxicity monitoring. Another study explicitly mentioned that ototoxicity monitoring was a standard of care in their hospital. Only one study reported using the relevant guidelines for monitoring ototoxicity. Specialized tests such as high-frequency audiometry, distortion product otoacoustic emissions, and vestibular tests were rarely used. Ototoxicity monitoring was influenced by awareness-related factors, technical factors, treatment-related factors, and organizational factors.

Conclusions:

Research on ototoxicity monitoring programs is in its early stages, highlighting the need for standardized practices and multidisciplinary collaboration to enhance health care services for HNC patients. A standardized approach, improved awareness, and the incorporation of patient perspectives are crucial to enhancing ototoxicity monitoring in HNC patients.
Asymptotic giant branch stars in the eROSITA-DE eRASS1 catalog
Authors: Guerrero M. A. , Montez R. , Ortiz R. , Toalá J. A. , Kastner J. H.
Published: July 2024

Context. Asymptotic giant branch (AGB) stars are not expected to be X-ray-emitters, yet a small fraction of them, the so-called X-AGBs, show X-ray emission that can be attributed to coronal activity of a companion or accretion onto one.

Aims. By searching the recently released SRG eROSITA-DE eRASS1 source catalog, we aim to increase the sample of known X-AGBs and investigate their X-ray and far-UV properties. So far, 36 X-AGBs have been reported, which includes 21 previous detections from ROSAT RASS, Chandra, and XMM-Newton and 15 recent detections from eROSITA eRASS1.

Methods. We cross-correlated the position of sources in the eROSITA-DE eRASS1 catalog with the largest available samples of AGB stars in order to find possible X-ray counterparts. We carefully checked the possible counterparts by comparing X-ray and near-IR K images, disregarding those affected by optical loading, those found to be diffuse sources, or those simply considered unreliable positional associations.

Results. We have found seven high-confidence X-AGBs and another seven possible ones. Accounting for previous X-ray detections, the sample of X-AGBs is increased by 11 new sources, increasing the sample of X-AGBs from 36 up to 47. Adding these sources to previous eROSITA-DE eRASS1 X-AGB detections, eROSITA has so far discovered 26 new X-AGBs, more than doubling the number of known X-AGBs. This demonstrates eROSITA’s capability to detect X-AGBs despite the challenge posed by the optical loading caused by their near-IR brightness, which makes the X-ray detection untrustworthy in a number of cases.

Conclusions. The eRASS1 X-AGBs tend to have a higher X-ray luminosity than that of previously detected X-AGBs, suggesting a bias toward brighter sources that is very likely due to the short exposure time of eRASS1 sources. A comparison of the X-ray and far-UV luminosity of X-AGBs with those of X-ray-emitter symbiotic stars (X-SySts) revealed an overlap in the X-ray luminosity range 1029.5 < LX (erg s−1) <1033.0. The average higher X-ray luminosity of X-SySts AGBs (≈1032 erg s−1) can be interpreted as X-ray emission arising from a boundary layer between an accretion disk and a white dwarf, whereas the average lower X-ray luminosity (≈5 × 1030 erg s−1) of X-AGBs would arise from an accretion disk around main-sequence or subgiant F-K companion stars.
Non-radial oscillations mimicking a brown dwarf orbiting the cluster giant NGC 4349 No. 127
Authors: Spaeth Dane , Reffert Sabine , Hunt Emily L. , Kaminski Adrian , Quirrenbach Andreas
Published: July 2024

Context. Several evolved stars have been found to exhibit long-period radial velocity variations that cannot be explained by planetary or brown dwarf companions. Non-radial oscillations caused by oscillatory convective modes have been put forth as an alternative explanation, but no modeling attempt has yet been undertaken.

Aims. We provide a model of a non-radial oscillation, aiming to explain the observed variations of the cluster giant NGC 4349 No. 127. The star was previously reported to host a brown dwarf companion, but whose existence was later refuted in the literature.

Methods. We reanalyzed 58 archival HARPS spectra of the intermediate-mass giant NGC 4349 No. 127. We reduced the spectra using the SERVAL and RACCOON pipelines, acquiring additional activity indicators. We searched for periodicity in the indicators and correlations between the indicators and radial velocities. We further present a simulation code able to produce synthetic HARPS spectra, incorporating the effect of non-radial oscillations, and compare the simulated results to the observed variations. We discuss the possibility that non-radial oscillations cause the observed variations.

Results. We find a positive correlation between chromatic index and radial velocity, along with closed-loop Lissajous-like correlations between radial velocity and each of the spectral line shape indicators (full width at half maximum, and contrast of the cross-correlation function and differential line width). Simulations of a low-amplitude, retrograde, dipole (l = 1, m = 1), non-radial oscillation can reproduce the observed behavior and explain the observables. Photometric variations below the detection threshold of the available ASAS-3 photometry are predicted. The oscillation and stellar parameters are largely in agreement with the prediction of oscillatory convective modes.

Conclusions. The periodic variations of the radial velocities and activity indicators, along with the respective phase shifts, measured for the intermediate-mass cluster giant NGC 4349 No. 127, can be explained by a non-radial oscillation.
Galaxy shapes in Magneticum
Authors: Valenzuela Lucas M. , Remus Rhea-Silvia , Dolag Klaus , Seidel Benjamin A.
Published: July 2024

Context. Despite being one of the most fundamental properties of galaxies that dictate the form of the potential, the 3D shapes are intrinsically difficult to determine from observations. The improving quality of triaxial modeling methods in recent years has made it possible to measure these shapes more accurately.

Aims. This study provides a comprehensive understanding of the stellar and dark matter (DM) shapes of galaxies and the connection between them. As these shapes are the result of the formation history of a galaxy, we investigate which galaxy properties they are correlated with, which will be especially useful for interpreting the results from dynamical modeling.

Methods. Using the hydrodynamical cosmological simulation Magneticum Pathfinder Box4 (uhr), we computed the stellar and DM intrinsic shapes of 690 simulated galaxies with stellar masses above 2 × 1010
M⊙ at three different radii with an iterative unweighted method. We also determined their morphologies, their projected morphological and kinematic parameters, and their fractions of in situ formed stars.

Results. The DM follows the stellar component in shape and orientation at three half-mass radii, indicating that DM is heavily influenced by the baryonic potential in the inner parts of the halo. The outer DM halo is independent of the inner properties such as the DM shape or galaxy morphology, however, and is more closely related to the large-scale anisotropy of the gas inflow. Overall, DM halo shapes are prolate, consistent with previous literature. The stellar shapes of galaxies are correlated with their morphology, with early-type galaxies featuring more spherical and prolate shapes than late-type galaxies out to 3 R1/2. Galaxies with more rotational support are flatter, and the stellar shapes are connected to the mass distribution, though not to the mass itself. In particular, more extended early-type galaxies have larger triaxialities at a given mass. Finally, the shapes can be used to better constrain the in situ fraction of stars when combined with the stellar mass.

Conclusions. The relations between shape, mass distribution, and in situ formed star fraction of galaxies show that the shapes depend on the details of the accretion history through which the galaxies are formed. The similarities between DM and stellar shapes in the inner regions of galaxy halos signal the importance of baryonic matter for the behavior of DM in galaxies and will be of use for improving the underlying assumptions of dynamical models for galaxies in the future. However, at large radii the shapes of the DM are completely decoupled from the central galaxy, and their shapes and spin are coupled more to the large scale inflow than to the galaxy in the center.
Constraints on fast radio burst emission in the aftermath of gamma-ray bursts
Authors: Patricelli B. , Bernardini M. G. , Ferro M.
Published: July 2024

Context. Fast radio bursts (FRBs) are highly energetic radio transients with a duration of some milliseconds. Their physical origin is still unknown. Many models consider magnetars as possible FRB sources, which is supported by the observational association of FRBs with the galactic magnetar SGR 1935+2154. Magnetars are also thought to be the source of the power of a fraction of gamma-ray bursts (GRBs), which means that the two extreme phenomena might have a common progenitor.

Aims. We placed constrains on this hypothesis by searching for possible associations between GRBs and FRBs with currently available catalogues and by estimating whether an association can be ruled out based on the lack of a coincident detection.

Methods. We cross-matched all the Neil Gehrels Swift Observatory (Swift) GRBs detected so far with all the well-localised FRBs reported in the FRBSTATS catalogue, and we looked for FRB-GRB associations considering both spatial and temporal constraints. We also simulated a synthetic population of FRBs associated with Swift GRBs to estimate how likely a joint detection with current and future radio facilities is.

Results. We recovered two low-significance possible associations that were reported before from a match of the catalogues: GRB 110715A/FRB 20171209A and GRB 060502B/FRB 20190309A. However, our study shows that based on the absence of any unambiguous association so far between Swift GRBs and FRBs, we cannot exclude that the two populations are connected because of the characteristics of current GRB and FRB detectors.

Conclusions. Currently available observational data are not sufficient to clearly exclude or confirm whether GRBs and FRBs are physically associated. In the next decade, the probability of detecting joint GRB-FRB events will be higher with new generations of GRB and FRB detectors, if any: future observations will therefore be key to placing more stringent constraints on the hypothesis that FRBs and GRBs have common progenitors.
The mass of the white dwarf in YY Dra (=DO Dra): Dynamical measurement and comparative study with X-ray estimates
Authors: Álvarez-Hernández A. , Torres M. A. P. , Shahbaz T. , Rodríguez-Gil P. , Gazeas K. D. , Sánchez-Sierras J. , Jonker P. G. , Corral-Santana J. M. , Acosta-Pulido J. A. , Hakala P.
Published: July 2024

We present a dynamical study of the intermediate polar cataclysmic variable YY Dra based on time-series observations in the K band, where the donor star is known to be the major flux contributor. We covered the 3.97-h orbital cycle with 44 spectra taken between 2020 and 2022 and two epochs of photometry observed in 2021 March and May. One of the light curves was simultaneously obtained with spectroscopy to better account for the effects of irradiation of the donor star and the presence of accretion light. From the spectroscopy, we derived the radial velocity curve of the donor star metallic absorption lines, constrained its spectral type to M0.5–M3.5 with no measurable changes in the effective temperature between the irradiated and non-irradiated hemispheres of the star, and measured its projected rotational velocity vrot sin i = 103 ± 2 km s−1. Through simultaneous modelling of the radial velocity and light curves, we derived values for the radial velocity semi-amplitude of the donor star, K2 = 188−2+1 km s−1, the donor to white dwarf mass ratio, q = M2/M1 = 0.62 ± 0.02, and the orbital inclination, i = 42°−1°+2°. These binary parameters yield dynamical masses of M1 = 0.99−0.09+0.10 M⊙ and M2 = 0.62−0.06+0.07 M⊙ (68 per cent confidence level). As found for the intermediate polars GK Per and XY Ari, the white dwarf dynamical mass in YY Dra significantly differs from several estimates obtained by modelling the X-ray spectral continuum.
L’échocardiographie chez les bovins
Authors: Ravary-Plumioën Bérangère , Plassard Vincent
Published: July 2024

L’exploration échographique du cœur chez les bovins peut être réalisée comme chez l’homme ou chez les équidés et les carnivores domestiques. Toutefois, il convient d’adapter la technique à l’anatomie et à la dimension spécifique de l’espèce bovine (membre antérieur gênant l’accès au cœur, côtes larges, présence éventuelle des poumons dans la zone d’exploration) ainsi qu’aux sondes échographiques disponibles (taille et fréquence).

L’échocardiographie est l’examen complémentaire de choix dans le diagnostic des principales affections cardiaques des bovins, comme les péricardites, les endocardites ou les malformations cardiaques congénitales, d’autant plus que les signes cliniques associés à ces affections peuvent être frustres et peu spécifiques.

Alors qu’elle est encore peu réalisée en pratique courante par les praticiens, faute d’équipements adaptés et de connaissances, cet article présente la technique, l’aspect échographique normal du cœur ainsi que les principales lésions qui peuvent être détectées par échocardiographie afin de permettre à quiconque de se former et de proposer aux éleveurs cet examen complémentaire dans le cadre d’une démarche diagnostique raisonnée.
Coccidiose clinique à Eimeria alabamensis
chez des veaux allaitants
Authors: Chartier Christophe , Ravinet Nadine , Maytie Brice , Chauvin Alain
Published: July 2024

La coccidiose bovine à Eimeria alabamensis est décrite principalement dans les pays du nord de l’Europe. Elle se manifeste par une diarrhée chez des animaux de 1ère année dans les 3 semaines après leur sortie sur des pâturages dits à risque, c’est-à-dire utilisés d’une année à l’autre par les veaux.

Nous décrivons un cas clinique de coccidiose apparue en Vendée sur des veaux de race Blonde d’Aquitaine, âgés de 1,5 à 3 mois, quelques jours après leur sortie sur une parcelle.

Le diagnostic est réalisé par un examen coproscopique quantitatif mettant en évidence de nombreux animaux excrétant une grande quantité d’ookystes d’Eimeria alabamensis.

La conduite de ces veaux avec leurs mères impliquant le passage dans plusieurs parcelles et bâtiments ne permet pas d’identifier formellement les circonstances d’apparition de cette coccidiose. Les caractéristiques de la coccidiose à E. alabamensis sont rappelées et comparées aux deux autres coccidioses majeures des bovins en bâtiment, E. bovis et E. zuernii.
Études de cas en alimentation des ruminants :
gestion d’un ensilage de maïs très riche en amidon
Authors: Enjalbert Francis
Published: July 2024

Avec une ration à base d’ensilage de maïs récolté tôt mais très riche en amidon, il est impératif de s’assurer que la structure physique et / ou l’association à un fourrage fibreux permettent une rumination suffisante. En outre, il faut éviter d’ajouter à la ration un concentré riche en amidon dégradable comme le blé, et favoriser un étalement des repas en faisant plusieurs distributions par jour.
Mycotoxicose et baisse de production
chez des vaches laitières
Authors: Guelou Kevin , Dupin Jean-Christophe , Tonnin Christophe , Liron Marie
Published: July 2024

A la fin du mois d’août 2016, un éleveur de 35 vaches Montbéliardes du Doubs est confronté sur plusieurs animaux (n = 20) à de la fièvre, de la tachypnée, une baisse de la production laitière, et de la dyspnée sur quelques vaches (n = 6).

L’apparition des signes cliniques est concomitante à l’introduction du seigle récemment récolté dans le concentré distribué aux vaches en lactation.
L’examen par le vétérinaire de cet aliment permet de mettre en évidence des structures noires, de quelques mm à 2 cm, compatibles avec des sclérotes. Après tri, la pesée des sclérotes révèle une contamination de l’ordre de 9,8 %, alors que la réglementation tolère une teneur maximale en sclérotes de 1 g/kg de céréale non moulue. La recherche de mycotoxines (chromatographie couplée à de la spectrométrie de masse) montre une teneur en alcaloïdes de l’ergot de 54,85 mg/kg de seigle. Selon le poids vif des animaux et la quantité de seigle ingérée, la dose d’alcaloïdes de l’ergot reçue par les animaux est de 0,06 à 0,25 mg/kg de PV.

L’analyse de la bibliographie rapporte des signes cliniques compatibles avec ceux rencontrés dans ce cas clinique. L’augmentation de la température corporelle est consécutive à l’augmentation de la libération d’hormone T3, à l’origine d’une augmentation de la production de chaleur ainsi qu’à une baisse des pertes de chaleur résultant de l’effet vasoconstricteur des alcaloïdes.

Ce dernier effet a été exacerbé par l’exposition des animaux à des fortes chaleurs à cette période. La baisse de production laitière est le résultat de la baisse d’ingestion consécutive à la hausse de la température centrale, et à l’effet inhibiteur des alcaloïdes de l’ergot sur la libération de prolactine, hormone essentiel pour la lactation.
Stress thermique chez les bovins : bases physiopathologiques
Authors: Karl Florian , Raboisson Didier
Published: July 2024

Les bovins, animaux homéothermes, présentent une zone de thermoneutralité. Lorsque cette zone est dépassée, la température corporelle augmente et une dépense d’énergie supplémentaire, par rapport à l’entretien, est nécessaire pour restaurer la température corporelle physiologique. L’ensemble des paramètres extérieurs entraînant ce processus constitue ce que l’on appelle le stress thermique.

Le THI (index température-humidité) permet d’établir un seuil à partir duquel la vache est soumise à un stress thermique. Les réponses physiologiques visent à une réduction de la production de chaleur (diminution de l’ingestion, baisse du métabolisme), et à une élimination de celle-ci (vasodilatation, transpiration, augmentation de la fréquence respiratoire).

Le stress thermique a des conséquences multiples sur les bovins : baisse d’immunité, augmentation des infections, baisse de production laitière et impact sur la qualité du lait (baisse des taux protéique et taux butyreux, augmentation des comptages cellulaires, augmentation de l’incidence des mammites cliniques), dégradation de la reproduction, baisse de croissance des veaux.

Ces indicateurs, faciles à mesurer sur le terrain, s’expliquent en particulier par un remaniement des équilibres hormonaux liés à l’exposition des vaches à la chaleur.

L’hormone de croissance et les hormones thyroïdiennes, responsables d’une production de chaleur indirecte, sont diminuées. A contrario, les glucocorticoïdes, vasodilatateurs, favorisent la dissipation de chaleur et les vaches présentent une augmentation de la glucocortisolémie.

Les veaux issus de mères exposées à un stress thermique sont, quant à eux, soumis au stade fœtal à différentes modifications (baisse de la fonction placentaire, augmentation de la température fœtale, baisse de croissance des tissus fœtaux, …), ayant plusieurs conséquences (augmentation de la mortalité, poids plus faible à la naissance, production laitière plus faible, …).
Études de cas
en alimentation des ruminants :
vaches laitières avec traite au robot
Authors: Enjalbert Francis
Published: July 2024

En système de traite robotisée, le plan de rationnement doit respecter les contraintes de quantité de concentrés lors de la traite, pour rester compatible avec le passage des vaches au robot.

Aux outils de surveillance de consommation de concentrés fournis par le robot, il est important d’ajouter un contrôle de consommation de ration de base à l’auge.
Big data service outsourcing and cost-sharing choices for the manufacturer
Authors: Song Han , Shu Yu-Xin , Dai Ying , Zhou Lin , Li Hai-Yan
Published: July 2024

The proliferation of digital technologies has revolutionized various industries, prompting enterprises to prioritize investment in big data analytics. Despite the associated value, enterprises must carefully assess the cost proposition of such investment. This study models a supply chain with a manufacturer and a retailer, investigating big data investment decisions and strategies of manufacturer as leader across varying scenarios. The results show that: if the manufacturer focus only on the big data service level, it will choose not to outsource. In the case of non-outsourcing, the pre-production big data service level, the pre-sale big data service level and the retailer’s profit are higher, however, the manufacturer’s profit depends on fixed cost. Moreover, the manufacturer has three options: it chooses non-outsourcing if the profits of supply chain members are decreased, it chooses outsourcing without coordination mechanism if only considers maximizing own profit, it chooses outsourcing with coordination mechanism if considers the profits of other members. If outsourcing is considered, the manufacturer can decide its cost-sharing rate according to different situations. When consumers need products with high satisfaction, they will improve the big data service level. And, the increased price is also acceptable to consumers. When consumers pay more attention to low price, appropriately reducing the big data service level can also satisfy consumers. In addition, this paper provides some management inspirations for decision-making and operation of supply chain.
Mortality from upper gastrointestinal tumors in colorectal cancer screening patients
Authors: Zessner-Spitzenberg Jasmin , Waldmann Elisabeth , Rockenbauer Lisa-Maria , Penz Daniela , Hinterberger Anna , Majcher Barbara , Asaturi Arno , Trauner Michael , Ferlitsch Monika
Published: July 2024

Background and study aims Currently, gastric cancer screening is only cost-effective in countries with high incidence. Integrated screening, in which gastroscopy is performed in conjunction with colonoscopy, could help reduce the gastric cancer screening procedure burden in countries with low or intermediate incidence. However, there is a lack of population-based studies to identify high-risk groups.

Methods In this retrospective analysis of a colorectal cancer (CRC) screening program database, we used Cox proportional hazards model to identify an association of high- and low-risk finding (polyps ≥ 10 mm or with high-grade dysplasia) with time to death from upper gastrointestinal cancer (esophageal and gastric). We estimated the 10-year mortality of upper gastrointestinal tumors in different 10-year age groups, stratified by sex and polyp finding at colonoscopy.

Results We included 349,856 CRC screening colonoscopies in our study. The median follow-up time was 5.22 years (95% confidence interval [CI] 5.21–5.24 years). Of the participants, 4.5% had polyps ≥ 10 mm or with high-grade dysplasia (HGD). At the end of the study period, 384 deaths from upper gastrointestinal cancer had occurred. Aside from age and sex, we found the presence of high-risk polyps to be significantly associated with upper gastrointestinal cancer death (hazard ratio 1.54, 95% CI 1.06–2.25, P = 0.025).

Conclusions CRC screening participants with polyps < 10 mm and no HGD have a lower risk for mortality from upper gastrointestinal cancers compared with participants with polyps > 10 mm and HGD. Future studies will demonstrate whether integrated screening with additional gastroscopy is effective in CRC screening participants with large or highly dysplastic polyps.
Substantial Differences in Proanthocyanidin Contents among Ginkgo biloba Leaf Extracts in Herbal Medicinal Products Obtained from the German Market
Authors: Germer Stefan , Ritter Thomas , Wurglics Mario
Published: July 2024

Pharmacologic activity of proanthocyanidins in Ginkgo biloba leaf extract has recently been reported. The objective of the present study was to screen proanthocyanidin contents in herbal medicinal products containing Ginkgo extracts. A recently published HPLC method for quantification of proanthocyanidins in G. biloba leaf extract EGb 761 was adopted to also be suitable for finished herbal medicinal products. The method was applied to 14 products from the German market. For each product, a set of three individual batches was purchased and analyzed. Substantial differences in proanthocyanidins contents were found among distinct products, ranging from 0.30 to 5.86%. The batch-to-batch variability within each product was low. The highest concentrations are in a similar range as, for example, the amount of Ginkgo terpene trilactones specified in the monograph for G. biloba leaf extract in the European Pharmacopeia. Although it has not yet been
established whether and to what extent proanthocyanidins contribute to the overall pharmacological or clinical efficacy of Ginkgo extracts, a potential impact on the purported benefits of different contents in proanthocyanidins cannot be ruled out. Quality assessment of different Ginkgo extracts in the future may include proanthocyanidins.
Oscillating direct electric current formed by a resonant tunneling diode inside a cavity with periodically oscillating mirrors
Authors: Guo Jiene , Šindelka Milan , Moiseyev Nimrod
Published: July 2024

A novel phenomenon is described that enables the control of the flux of free electrons through a resonance tunneling diode (RTD) via coupling the RTD to a quantized electromagnetic mode in a dark cavity. As the control parameter, one uses here the distance between the two cavity mirrors (which are set to oscillate in time). The effect is illustrated by carrying out standard scattering calculations of the electron flux. However, the only efficient way to rationalize the phenomenon and to be able to select the proper distance between the two cavity mirrors is to employ non-Hermitian quantum mechanics and the language of discrete resonance poles of the scattering matrix. The demonstrated ability to control the flux of free electrons by using a dark cavity might open a new field of research and development of controllable RTD devices.
The sound speed of the relativistic free electron gas
Authors: Faussurier Gérald
Published: July 2024

The sound speed of the relativistic free electron gas is derived and investigated. We examine the non-relativistic and ultra-relativistic limits. It is shown from first principles that the sound speed is lower than the velocity of light divided by 3. The question is open as whether taking into account positrons and photons in thermodynamic equilibrium with electrons, including other particles, or describing different fundamental forces can modify this result.
Vortex dynamics induced by a finite wall-mounted cylinder with various corner shapes
Authors: Zhang Lu-Rong , Li Jiang-Hua , Wang Yu-Ze , Qiu Xiang , Fu Yuan , Liu Yu-Lu
Published: July 2024

The flow around a finite wall-mounted cylinder with four different corner shapes (R/D=0,1/6,1/3,1/2) is numerically investigated at a Reynolds number of 1000 and a height-to-diameter ratio of 4. For the vortex dynamics, the vortex structures in the wake undergo a series of complex evolution processes, namely, shear layer separation, C vortex, Reverse C vortex, hairpin vortex, and vortex breakdown. The influence of R/D on the flow characteristics and vortex evolution has been studied. The results indicate that the mean hydrodynamic coefficients (C¯d and C¯l) and the mean reattachment distance (LP/D) decrease with the increasing R/D. Moreover, the flow separation for R/D=1/2 is delayed by 0.49D compared to that for R/D=0. The probability density function of the reverse-flow area at R/D=1/2 exhibits a symmetrical distribution, suggesting a balanced enlargement and contraction. Numerous hairpin vortices in the far wake exhibit clear periodic oscillation behavior resembling a Kármán-like pattern. Furthermore, as R/D increases, the oscillation frequency rises gradually as well as a forward shift in the high-strength vortex interaction, while the width of the near wake gradually narrows. The evolution of spanwise vorticity over time and the results of proper orthogonal decomposition modes confirm the alternating shedding and periodic oscillation pattern akin to Kármán vortex streets.
Dynamics of harbor seal whiskers at different angles of attack in wake flow
Authors: Zhao Hanghao , Zhang Zhimeng , Ji Chunning , Zhao Yawei , Li Xianghe , Du Muyuan
Published: July 2024

Harbor seals can exquisitely perceive and distinguish different hydrodynamic signals through their distinctive undulatory whiskers. In this study, an elastically supported Harbor seal whisker model undergoing one degree-of-freedom vibration in the cross-flow direction was positioned right downstream of a fixed cylinder and a flapping caudal fin model, respectively, as wake generators. The vibration responses, spectral frequencies, and fluid forces of the whisker model at different angles of attack (0° ≤ α ≤ 90°) are experimentally investigated. The reduced velocity, Ur, ranges from 4.0 to 26.0, and the Reynolds number, Re, varies within the range of 730–4770. The whisker model exhibits a combined vortex-induced vibration (VIV)—wake-induced vibration (WIV) response in the cylinder wake flow,whereas in the caudal fin wake flow, it displays a combination of VIV—wake-induced galloping response at α ≤ 45° and VIV–WIV response at α ≥ 60°. The frequency features of the wake generated by the fixed cylinder and the flapping caudal fin model, along with the increased VIV influence due to the angle of attack, cause the whisker model to exhibit different vibration characteristics. Understanding the vibration responses and fluid forces of the whisker model at various angles of attack in different wake flows is pivotal for future studies on developing whisker-inspired sensors.
Extreme events and extreme multistability in a nearly conservative system
Authors: Kumarasamy Suresh , Leo Kingston S. , Srinivasan Sabarathinam , Chudzik Agnieszka , Kathamuthu Thamilmaran , Kapitaniak Tomasz
Published: July 2024

This study investigates the emergence of extreme events in a complex variable dynamical system. In the absence of an external forcing, the model exhibits nearly Hamiltonian dynamics. When we set the system to a nearly conservative state and perturb it with external forcing, the formation of the onset of the extreme events was detected. By applying nullcline analysis and the system’s vector field, we explored the underlying mechanism that leads to extreme events. Furthermore, we have conducted a thorough investigation to show the dynamic origins of extreme amplitude events and their transitions. The hardware electronic experiment is used to validate the numerical results of the onset of extreme events, and the results obtained are in good agreement with one another.
Asian elephant (Elephas maximus) seminal plasma: establishing the proteome and effect on spermatozoa when added to cryomedium
Authors: Negus Cameron , Pinyopummin Anuchai , Mahasawangkul Sittidet , Hobbs Rebecca , Bathgate Roslyn
Published: July 2024

Context The removal or supplementation of ejaculates with seminal plasma (SP) can affect cryotolerance and post-thaw survival of spermatozoa in many species. In the Asian elephant (Elephas maximus), elucidation of the SP proteome and investigation of how it affects spermatozoa may enable improvement of cryopreservation protocols. Aims Herein, we characterise the Asian elephant SP proteome and investigate the impacts of SP on sperm cryotolerance in the presence of conspecific or heterospecific SP. Methods Proteomic analysis of Asian elephant SP was performed using mass spectrometry on nine samples from three individuals. In a separate study, SP was removed from six ejaculates and spermatozoa were resuspended in Tris extender supplemented with: no seminal plasma (NOSP), conspecific SP from ejaculates exhibiting ‘good’ (GSP, >60%) or mixed sperm total motility (MSP), or horse SP (HSP). Samples underwent cryopreservation, and sperm parameters were compared prior to cryopreservation and after thawing (0 and 2 h). Key results Mass spectrometry identified 155 proteins from an array of families. Significant differences were observed in post-thaw sperm quality between SP treatments: high concentrations of MSP (25%, v/v) displayed greater average path and straight-line velocity immediately after thawing (P < 0.05) and greater sperm motility index and beat cross frequency than NOSP after 2 h post-thaw incubation (P < 0.05). The addition of HSP improved sperm kinematic parameters compared to NOSP and GSP treatments (P < 0.05). Conclusions and implications These preliminary findings suggest the potential of SP to enhance the cryosurvival of Asian elephant spermatozoa, with HSP showing particularly promising results compared to conspecific SP (GSP). Further research into the specific effects of Asian elephant SP proteins is warranted.
A test of whether rabbit abundance increases following predator control in a rural landscape
Authors: Barron Mandy , de Burgh Natalie , Norbury Grant
Published: July 2024

Context In New Zealand and Australia, rural landowners believe that local control of invasive predators aimed at protecting the indigenous biota exacerbates European rabbit (Oryctolagus cuniculus) problems on their land. Aims We tested this using rabbit index data collected in replicated areas with and without predator control in rural landscapes of the Hawke’s Bay region of New Zealand. Methods Spotlight data were available from two ecological restoration areas. For the Cape to City area, data were collected from 2016 to 2021, with three sites subjected to ongoing predator control (traps deployed in 2016 and 2017) and two sites untreated. For the Poutiri Ao ō Tāne area, data were collected from 2012 to 2021, with two sites subjected to ongoing predator control (beginning in 2012) and three sites untreated. Generalised linear mixed-effects models were used to assess whether predator control was a statistically significant predictor of rabbit counts. Cameras were also deployed annually, beginning in 2015, in the treatment and non-treatment areas in Cape to City. Mixed-effects models were fitted to the camera detection data using a ‘Before After Control Impact’ framework to assess whether camera detection rates of rabbits changed with predator control. Key results Contrary to landowner expectations, fewer rabbits were counted under spotlight at the predator control sites at Cape to City, although no effect was detected in the camera detection data. More rabbits were counted on the predator control sites at Poutiri Ao ō Tāne, but this effect was not statistically significant and only became apparent in the last 2 years of the 9-year monitoring period. Conclusions The effects of predator control on rabbit abundance indices in the Hawke’s Bay region were contradictory and inconclusive. This suggests that the influence of predators on rabbit populations is minor compared with other sources of population limitation or regulation, such as disease and poor food quality. Implications The absence of a definitive predator effect should reassure landowners concerned about potential rabbit population outbreaks following predator control.
Secondary structure determines electron transport in peptides
Authors: Samajdar Rajarshi , Meigooni Moeen , Yang Hao , Li Jialing , Liu Xiaolin , Jackson Nicholas E. , Mosquera Martín A. , Tajkhorshid Emad , Schroeder Charles M.
Published: July 2024

Proteins play a key role in biological electron transport, but the structure–function relationships governing the electronic properties of peptides are not fully understood. Despite recent progress, understanding the link between peptide conformational flexibility, hierarchical structures, and electron transport pathways has been challenging. Here, we use single-molecule experiments, molecular dynamics (MD) simulations, nonequilibrium Green’s function-density functional theory (NEGF-DFT), and unsupervised machine learning to understand the role of secondary structure on electron transport in peptides. Our results reveal a two-state molecular conductance behavior for peptides across several different amino acid sequences. MD simulations and Gaussian mixture modeling are used to show that this two-state molecular conductance behavior arises due to the conformational flexibility of peptide backbones, with a high-conductance state arising due to a more defined secondary structure (beta turn or 3
10
helices) and a low-conductance state occurring for extended peptide structures. These results highlight the importance of helical conformations on electron transport in peptides. Conformer selection for the peptide structures is rationalized using principal component analysis of intramolecular hydrogen bonding distances along peptide backbones. Molecular conformations from MD simulations are used to model charge transport in NEGF-DFT calculations, and the results are in reasonable qualitative agreement with experiments. Projected density of states calculations and molecular orbital visualizations are further used to understand the role of amino acid side chains on transport. Overall, our results show that secondary structure plays a key role in electron transport in peptides, which provides broad avenues for understanding the electronic properties of proteins.
Ion channels of cold transduction and transmission
Authors: Lewis Cheyanne M. , Griffith Theanne N.
Published: July 2024

Thermosensation requires the activation of a unique collection of ion channels and receptors that work in concert to transmit thermal information. It is widely accepted that transient receptor potential melastatin 8 (TRPM8) activation is required for normal cold sensing; however, recent studies have illuminated major roles for other ion channels in this important somatic sensation. In addition to TRPM8, other TRP channels have been reported to contribute to cold transduction mechanisms in diverse sensory neuron populations, with both leak- and voltage-gated channels being identified for their role in the transmission of cold signals. Whether the same channels that contribute to physiological cold sensing also mediate noxious cold signaling remains unclear; however, recent work has found a conserved role for the kainite receptor, GluK2, in noxious cold sensing across species. Additionally, cold-sensing neurons likely engage in functional crosstalk with nociceptors to give rise to cold pain. This Review will provide an update on our understanding of the relationship between various ion channels in the transduction and transmission of cold and highlight areas where further investigation is required.