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Bile acid signaling in the regulation of whole body metabolic and immunological homeostasis

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Science china(Life Sciences) 2024年第5期67卷 865-878页

作者： Wei Jia Yitao Li Kenneth c.P.cheung Xiaojiao Zheng School of chinese Medicine Hong Kong Baptist UniversityHong KongChina center for Translational Medicine and Shanghai Key Laboratory of Diabetes Mellitus Shanghai Sixth People's Hospital Affiliated to Shanghai JiaoTong University School of MedicineShanghai 200233China

Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune homeostasis.Through the enterohepatic circulation,BAs are synthesized,metabolized,and reabsorbed,with a portion entering the vascular circulation and distributing systemically.This allows BAs to interact with receptors in all major organs,leading to organ-organ interactions that regulate both local and global metabolic processes,as well as the immune system.This review focuses on the whole-body effects of BA-mediated metabolic and immunological regulation,including in the brain,heart,liver,intestine,eyes,skin,adipose tissue,and muscle.Targeting BA synthesis and receptor signaling is a promising strategy for the development of novel therapies for various diseases throughout the body.

关键词： bile acid whole body metabolism immunity

Gustatory responsiveness in Vespula germanica workers:exploring the interplay between sensory perception and task specialization

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Insect Science 2024年第2期31卷 587-598页

作者： Analia Mattiacci carolina Mengoni Gonalons MaitéMasciocchi Juan c.corley Grupo de Ecologia de Poblaciones de Insectos IFAB(CONICETINTA EEA Bariloche)BarilocheArgentina Departamento de Ecologia Centro Regional Universitario BarilocheUniversidad Nacional Del ComahueBarilocheArgentina Departamento de Biodiversidad y Biologia Experimental Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina

Workers'task specialization and division of labor are critical features of social insects'ecological success.It has been proposed that the division of labor relies on response threshold models:individuals varying their sensitivity(and responsiveness)to biologically relevant stimuli and performing a specific task when a stimulus exceeds an internal threshold.In this work,we study carbohydrate and protein responsiveness and their relation to worker task specialization in Vespula germanica,an invasive social wasp.The sucrose and peptone responsiveness of two different subcastes,preforagers and foragers,was determined by stimulating the antenna of the wasps with increasing concentrations of the solution and quantifying whether each concentration elicited a licking response.We studied responsiveness in five different ways:(1)response threshold,(2)concentration 50(concentration to which at least 50%of wasps responded),(3)maximum response,(4)mean scores and(5)median scores.Our results suggest that V germanica foragers are more sensitive to sucrose(lower thresholds)than preforager workers.However,we found no differences for peptone thresholds(i.e.,a protein resource).Nonetheless,this is the first study to investigate response thresholds for protein resources.The intercaste variation in sucrose responsiveness shown in our work contributes to the existing knowledge about response threshold theory as a mechanism for task specialization observed in V germanica.

关键词： carbohydrates responsiveness division of labor protein responsiveness response thresholds models social insect yellow jacket

Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen ZHAO Zhenli cHEN c.T.MUTASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

The stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. The oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. The effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. The growth rates of two most unstable modes when δ ckness and the half height of the channel, respectively. However, their vorticities are different. The vorticity of the most unstable mode is symmetric, while the other is asymmetric. The Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ ct when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. The effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. The energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. The effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd3+-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.c.Andrade Optical and Photothermal Spectroscopy Group (GEOF) Center for Studies in Natural Resources (CERNA)State University of Mato Grosso do Sul(UEMS) Renato Archer Information Technology center Institute of Physics of Sao carlos University of S?o Paulo

Nd3+-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio（FIR） technique.Nevertheless,at high Nd3+concentrations,energy transfer（ET） processes such as optical reabsorption and cross-relaxation can affect the Nd3+emission,which has been little explored in the literature.Therefore,the present work investigated the use of Nd3+-doped tellurite glass(samples doped with Nd3+at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%) in fluorescence thermometers,in the temperature range from 299 to 371 K.The results indicate a strong dependence of the FIR parameters on the Nd3+concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd3+emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio4F5/2→4I9/2/4F3/2→4I9/2is observed for samples doped with higher amounts of Nd3+.The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd3+ions.

关键词： Fluorescence intensity ratio Judd-Ofelt Nd3+-doped tellurite glass Optical thermometry Rare earths

Geochemistry and depositional environment of fuchsite quartzites from Sargur Group,western Dharwar craton,India

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Acta Geochimica 2024年第3期43卷 555-570页

作者： c.S.Sindhuja G.Harshitha c.Manikyamba K.S.V.Subramanyam cSIR(council of Scientific and Industrial Research)-National Geophysical Research Institute(NGRI) Uppal RoadHyderabad 500007India

Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar craton including the oldest(~3.3 Ga)Sargur Group of western Dharwar craton.The present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation history.Their major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and rutile.The geochemical com-positions are characterized by high SiO_(2),Al_(2)O_(3),low MgO,caO,strongly enriched cr(1326–6899 ppm),Ba(1165–3653 ppm),Sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(Ucc).The Ucc normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/Sm)Ucc=0.33–0.95]compared to heavy REE[(Gd/Yb)_(Ucc)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered barites.The overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin environ-ment.The comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by cr-richfluids released during high-grade metamorphism of associated ultramafic rocks.The Sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of cr-richfluids and the formation of fuchsite quartzite during or after the orogeny.Thesefindings sug-gest a pre-existing stable crust prior to the Sargur Group and the link between orogenic events and various mineral deposits in the Dharwar craton.

关键词： Dharwar craton Ghattihosahalli Fuchsite quartzite Provenance Depositional setting

Radiative decays D*(s)→ D(s)γ in covariant confined quark model

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chinese Physics c 2024年第2期48卷 45-56页

作者： c.T.Tran M.A.Ivanov P.Santorelli Q.c.Vo Department of Physics HCMC University of Technology and EducationVo Van Ngan 1700000 Ho Chi Minh CityVietnam Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia Dipartimento di Fisica"E.Pancini" Universitàdi Napoli Federico ⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto Nazionale di Fisica Nucleare Sezione di Napoli80126 NapoliItaly University of Science 700000 Ho Chi Minh CityVietnam

Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢcollaborations.The radiative couplings gD*Dγencoding nonperturbative QcD effects are calculated in the framework of the covariant confined quark model developed by us.We compare our results with other theoretical studies and experimental data.The couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).The most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QcD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QcD sum rules.

关键词： covariant quark model radiative decay charmed meson

Mechanistic insight into cr(Ⅵ)retention by Si-containing ferrihydrite

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Journal of Environmental Sciences 2024年第5期139卷 217-225页

作者： Ying Hu Qiang Xue Honghan chen Huaming Guo Kenneth c.carroll Song Wang MOE Key Laboratory of Groundwater circulation and Environmental Evolution School of Water Resources and EnvironmentChina University of Geosciences(Beijing)Beijing 100083China Beijing Key Laboratory of Water Resources and Environmental Engineering School of Water Resources and EnvironmentChina University of GeosciencesBeijing 100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China Plant&Environmental Science New Mexico State UniversityNM 88003USA Institute of Theoretical chemistry College of ChemistryJilin UniversityChangchun 130023China

Hexavalent chromium[cr(Ⅵ)]causes serious harm to the environment due to its high toxicity,solubility,and mobility.Ferrihydrites(Fh)are the main adsorbent and trapping agent of cr(Ⅵ)in soils and aquifers,and they usually coexist with silicate(Si),forming Si-containing ferrihydrite(Si-Fh)mixtures.However,the mechanism of cr(Ⅵ)retention by Si-Fh mixtures is poorly understood.In this study,the behaviors and mechanisms of cr(Ⅵ)adsorption onto Si-Fh with different Si/Fe molar ratios was investigated.Transmission electron microscope,Fourier transform infrared spectroscopy,X-ray diffraction,X-ray photoelectron spectroscopy,and other techniques were used to characterize Si-Fh and cr(Ⅵ)-loading of Si-Fh.The results show that specific surface area of Si-Fh increases gradually with increasing Si/Fe ratios,but cr(Ⅵ)adsorption on Si-Fh decreases with increasing Si/Fe ratios.This is because with an increase in Si/Fe molar ratio,the point of zero charge of Si-Fh gradually decreases and electrostatic repulsion between Si-Fh and cr(Ⅵ)increases.However,the complexation of cr(Ⅵ)is enhanced due to the increase in adsorbed hydroxyl(A-OH-)on Si-Fh with increasing Si/Fe molar ratio,which partly counteracts the effect of the electrostatic repulsion.Overall,the increase in the electrostatic repulsion has a greater impact on adsorption than the additional complexation with Si-Fh.Density functional theory calculation further supports this observation,showing the increases in electron variation of bonding atoms and reaction energies of inner spherical complexes with the increase in Si/Fe ratio.

关键词： Hexavalent chromium Ferrihydrite Si/Fe ratio cr(Ⅵ)Adsorption

Liver transplantation as an alternative for the treatment of neuroendocrine liver metastasis: Appraisal of the current evidence

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 146-153页

作者： Philip c.Muller Matthias Pfister Dilmurodjon Eshmuminov Kuno Lehmann Department of Surgery and Transplantation University Hospital ZurichRämistrasse 100Zurich CH-8091Switzerland

Background:Liver transplantation(LT)for neuroendocrine liver metastases(NELM)is still in debate.Studies comparing LT with liver resection(LR)for NELM are scarce,as patient selection is heterogeneous and experience is limited.The goal of this review was to provide a critical analysis of the evidence on LT versus LR in the treatment of NELM.Data sources:A scoping literature search on LT and LR for NELM was performed with PubMed,including English articles up to March 2023.Results:International guidelines recommend LR for NELM in resectable,well-differentiated tumors in the absence of extrahepatic metastatic disease with superior results of LR compared to systemic or liver-directed therapies.Advanced liver surgery has extended resectability criteria whilst entailing increased perioperative risk and short disease-free survival.In highly selected patients(based on the Milan criteria)with unresectable NELM,oncologic results of LT are promising.Prognostic factors include tumor biology(G1/G2)and burden,waiting time for LT,patient age and extrahepatic spread.Based on low-level evi-dence,LT for low-grade NELM within the Milan criteria resulted in improved disease-free survival and overall survival compared to LR.The benefits of LT were lost in patients beyond the Milan NELM-criteria.conclusions:With adherence to strict selection criteria especially tumor biology,LT for NELM is becoming a valuable option providing oncologic benefits compared to LR.Recent evidence suggests even stricter selection criteria with regard to tumor biology.

关键词： Liver transplantation Neuroendocrine liver metastases Liver resection Selection criteria Tumor biology

Automated Machine Learning Algorithm Using Recurrent Neural Network to Perform Long-Term Time Series Forecasting

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computers, Materials & continua 2024年第3期78卷 3529-3549页

作者： Ying Su Morgan c.Wang Shuai Liu Department of Statistics and Data Science University of Central FloridaOrlandoFL32816-2370USA School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing100048China

Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically relies on expert input and necessitates substantial manual involvement.This manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construction of time series models.The complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple junctures.To surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent Neural Networks,harnessing memory cells and gating mechanisms to facilitate long-term time series prediction.However,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series tasks.Therefore,our research demonstrates that this innovative approach outperforms the traditional Autoregressive Integrated Moving Average(ARIMA)method in forecasting long-term univariate time series.ARIMA is a high-quality and competitive model in time series prediction,and yet it requires significant preprocessing efforts.Using multiple accuracy metrics,we have evaluated both ARIMA and proposed method on the simulated time-series data and real data in both short and long term.Furthermore,our findings indicate its superiority over alternative network architectures,including Fully connected Neural Networks,convolutional Neural Networks,and Nonpooling convolutional Neural Networks.Our AutoML approach enables non-professional to attain highly accurate and effective time series forecasting,and can be widely applied to various domains,particularly in business and finance.

关键词： Automated machine learning autoregressive integrated moving average neural networks time series analysis