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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Calibration of the solar X-ray Detector on-board the Macao science satellite-1B for soft X-ray Detection

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science China Earth sciences 2025年第1期68卷 11-26页

作者： man-Hei NG Xiaoping ZHANG Jianwu CHEN Yongqiang sHI Fuchang ZUO Wenxi PENG Weichun FU Liansheng LI Pengwei LUO Chi-Long TANG Guozheng ZHANG Zhiwu MEI Li WANG Cunhui LI Jiaming OU Yanyan XU state Key Laboratory of Lunar and Planetary sciences Macau University of Science and Technology China National space Administration (CNsA) Macau Center for Space Exploration and Science space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of Physics

The solar X-ray Detector(sXD) on-board the Macao science satellite-1B(Mss-1B) was successfully launched via the Chinese Long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The Mss-1B/soft X-ray Detection Units(sXDUs) employ two silicon drift detectors(sDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the sXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the Mss-1B/sXDUs, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the Mss-1B/sXDUs to the data collected by the Geostationary Operational Environmental satellite(GOEs), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the Mss-1B/sXDUs, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative Mss-1B/solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays, thereby making valuable contributions to the advancements in solar research.

关键词： Macao science satellite-1B (Mss-1B) Calibration solar X-Ray Detector spectrometer soft X-rays solar flares solar abundances

Combustion characteristics of high ash Indian thermal,heat affected coal and their blends

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International Journal of Coal science & Technology 2021年第5期8卷 1078-1087页

作者： subhajit aich Barun Kumar Nandi s.mantra Bhattacharya Department of Fuel Minerals and Metallurgical Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad 826004JharkhandIndia

Onsite mine fire generates large volumes of heat-affected coal in Jharia coalfields,*** utilization of such heat-affected coal in thermal utilities is not feasible as such coal does not have the desirable volatile matter required for *** the present work,experimental studies have been carried out to investigate the possible utilization of such heat-affected coal in thermal utilities by blending with other ***-affected coal(31%ash and 5300 kcal/kg GCV)collected from Jharia coalfield were blended with thermal coal(28%ash and 5650 kcal/kg GCV)in different ratios of 90:10,80:20,70:30 and 60:40 to identify the desirable blend ratio for burning of blended coal in thermal *** characteristics of all the coals were carried out using *** combustion parameters such as ignition temperature,peak temperature,burnout temperature,ignition index,burnout index,combustion performance index,rate and heat intensity index of the combustion process and activation energy were evaluated to analyse the combustion *** and theoretical analysis shows the blend ratio of 90:10 can be used in place of only thermal coal in utilities to reduce the fuel cost.

关键词： Coal blends Heat affected coal Combustion indices TGA-DTG Burning profile Mass gain analysis

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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science China Chemistry 2025年第1期68卷 288-296页

作者： shuai Liu Wen-Qiang Xu Ying-Tong Di man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School shenzhen Bay Laboratory state Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University state Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase spe F and P450 monooxygenase spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, spe F/spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

A critical review of the emerging research on the detection and assessment of microplastics pollution in the coastal,marine,and urban Bangladesh

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Frontiers of Environmental science & Engineering 2022年第10期16卷 39-52页

作者： Zaki Alam Pushan Ehsanur Rahman Nafisa Islam Nirupam aich Department of Chemical Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh Department of Civil Environmentaland Geo-EngineeringUniversity of Minnesota-Twin CitiesMinneapolisMN 55455USA Department of Civil Structural and Environmental EngineeringUniversity at BuffaloThe State University of New YorkBuffaloNY 14260USA

The research on the extent and effects of microplastics pollution in the Global south is only getting *** is a south Asian country with one of the fastest growing economies in the world,however,such exponential economic growth has also increased the pollution threats to its natural and urban *** this paper,we reviewed the recent primary research on the assessment of the extent of microplastics pollution in *** online databases,we developed a compilation of emergingresearch articles that detected and quantified microplastics in different coastal,marine,and urban environments in *** of the studies focused on the coastal environment(e.g.,beach sediment)and marine fish,while limited data were available for the urban *** also discussed the relationship of the type of anthropogenic activities with the observed microplastic *** Cox's Bazar sea beach in south-east Bangladesh experienced microplastics pollution due to tourism activities,while fishing and other anthropogenic activities led to microplastics pollution in the Bay of *** microplastics larger than 1 mm were prevalent in the beach sediments,smaller microplastics with size below 0.5 mm were prevalent in marine fish ***,the differences m microplastic abundance,size,shape,color,and polymer type found were depended on the sampling sites and relevant anthropogenic *** is imperative to identify majorsources of microplastics pollution in both natural and urban environment,determine potential environmental and human health effects,and develop mitigating and prevention strategies for reducing microplastics pollution.

关键词： Plastic pollution Waste management Global south sustainability Marine pollution

Asymptotic false discovery control of the Benjamini-Hochberg procedure for pairwise comparisons

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science China Mathematics 2025年第1期 223-252页

作者： Weidong Liu Dennis Leung Qi-man shao school of Mathematical sciences Shanghai Jiao Tong University school of Mathematics and statistics University of Melbourne Department of statistics and Data science SICMSouthern University of Science and Technology

In a one-way analysis-of-variance(ANOVA) model,the number of pairwise comparisons can become large even with a moderate number of *** by this,we consider a regime with a growing number of groups and prove that,when testing pairwise comparisons,the Benjamini-Hochberg(BH) procedure can asymptotically control false discoveries,despite the fact that the involved t-statistics do not exhibit the wellknown positive dependence structure required for exact false discovery rate(FDR) *** Tukey's perspective that the difference between the means of any two groups cannot be exactly zero,our main result provides control over the directional false discovery rate and directional false discovery proportion.A key technical contribution of our work is demonstrating that the dependence among the t-statistics is sufficiently weak to establish the convergence result typically required for asymptotic FDR *** analysis does not rely on conventional assumptions such as normality,variance homogeneity,or a balanced design,thereby offering a theoretical foundation for applications in more general settings.

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Effect of weathering on physico-chemical properties and combustion behavior of an Indian thermal coal

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International Journal of Coal science & Technology 2019年第1期6卷 51-62页

作者： subhajit aich Barun Kumar Nandi s.mantra Bhattacharya Department of Fuel and Mineral Engineering Indian Institute of Technology (Indian School of Mines)Dhanbad Dhanbad Jharkhand 826004India

An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of -200 mm size ROM thermal coal on a concrete floor. Coal sample from the stockpile were collected at 30 days interval for analysis of various chemical properties like;proximate analysis, ultimate analysis, gross calorific value (GCV) and various combustion related properties such as ignition temperature, peak temperature, burnout temperature, maximum combustion rate, ignition index, burnout index, combustion performance index and combustion rate intensity index. Experimental results show that, due to weathering of coal fixed carbon decreased from 35.6% to 19.9%, elemental carb on (C) decreased from 46.6% to 28.6%, hydrogen (H) decreased from 3.3% to 2.9% and GCV decreased by up to 55% of original value during 330 days of storage of coal in an open atmosphere. Ash con tent of coal increased form 29.2% to 46.6% due to loss of combustibles. sulfur (s) of coal was found to get increased from 0.33% to 1.08% during storage. The activation energy of coal combustion increased from 22 kJ/mol to 54 kJ/mol. Variation in combustion parameters signifies that weathering has significant negative impact on coal combustion properties as coal become difficult to ignite.

关键词： Weathering of coal TGA-DTG Combustibles Coal combustion Activation energy

searching For(2+1)-dimensional nonlinear Boussinesq equation from(1+1)-dimensional nonlinear Boussinesq equation

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Communications in Theoretical Physics 2023年第7期75卷 58-61页

作者： man Jia s Y Lou school of Physical science and Technology Ningbo UniversityNingbo315211China

A novel(2+1)-dimensional nonlinear Boussinesq equation is derived from a(1+1)-dimensional Boussinesq equation in nonlinear schr?dinger type based on a deformation *** integrability of the obtained(2+1)-dimensional Boussinesq equation is guaranteed by its Lax pair obtained directly from the Lax pair of the(1+1)-dimensional Boussinesq *** of the effects of the deformation,the(2+1)-dimensional Boussinesq equation admits a special travelling wave solution with a shape that can be deformed to be asymmetric and/or multivalued.

关键词： (2+1)-dimensional Boussinesq equation deformation algorithm lax integrable an implicit travelling wave solution

Relationship between proximate analysis parameters and combustion behaviour of high ash Indian coal

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International Journal of Coal science & Technology 2020年第4期7卷 766-777页

作者： subhajit aich Dibyajyoti Behera Barun Kumar Nandi s.mantra Bhattacharya Department of Fuel Minerals and Metallurgical Engineering Indian Institute of Technology(Indian School of Mines)DhanbadDhanbadJharkhand 826004India

This work presents the analysis of combustion characteristics of high ash Indian coal(28%-40%)collected from different mines of singaurali coalfield,*** the coal samples were characterized by proximate and gross calorific value *** performance of the coals were characterised using thermo-gravimetric analysis to identify the burning profile of individual *** combustion kinetic parameters such as ignition temperature,peak temperature and burnout temperature,ignition index and burnout index,combustion performance index plus rate and intensity index of combustion process,activation energy were determined to analyse the combustion behaviour of *** all these combustion properties were compared with the volatile matter,ash,fixed carbon and fuel ratio of each *** analysis shows that with increase in ash content,combustion performance initially increases and later ***,coal with(25±1.75)%volatile matter,20%-35%ash and fuel ratio 1.4-1.5 were found to be optimum for coal combustion.

关键词： TGA-DTG Proximate analysis Combustion kinetics Activation energy Burning profile