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Tumor microenvironment involvement in colorectal cancer progression via Wnt/β-catenin pathway:Providing understanding of the complex mechanisms of chemoresistance

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World Journal of Gastroenterology 2022年第26期28卷 3027-3046页

作者： María Belén Novoa Díaz María Julia Martín Claudia Gentili departamento de Biología Bioquímica y FarmaciaUniversidad Nacional del Sur(UNS)-INBIOSUR(CONICET-UNS)Bahía Blanca 8000Argentina departamento de Química Universidad Nacional del Sur(UNS)-INQUISUR(CONICET-UNS)Bahía Blanca 8000Argentina

Colorectal cancer(CRC)continues to be one of the main causes of death from cancer because patients progress unfavorably due to resistance to current *** of the Wnt/β-catenin pathway plays a fundamental role in the genesis and progression of several types of cancer,including *** many subtypes of CRC,hyperactivation of theβ-catenin pathway is associated with mutations of the adenomatous polyposis coli ***,it can also be associated with other *** recent years,studies of the tumor microenvironment(TMe)have demonstrated its importance in the development and progression of *** this tumor nest,several cell types,structures,and biomolecules interact with neoplastic cells to pave the way for the spread of the ***-communications between tumor cells and the TMe are then established primarily through paracrine factors,which trigger the activation of numerous signaling *** advances in the field of oncology have been made in the last *** Minireview aims to actualize what is known about the central role of the Wnt/β-catenin pathway in CRC chemoresistance and aggressiveness,focusing on crosscommunication between CRC cells and the *** this analysis,our main objective was to increase the understanding of this complex disease considering a more global *** many treatments for advanced CRC fail due to mechanisms involving chemoresistance,the data here exposed and analyzed are of great interest for the development of novel and effective therapies.

关键词： Colorectal cancer β-catenin pathway Tumor stroma Tumor microenvironment factors Cancer progression Drug resistance

fixed points of n-valued maps on surfaces and the Wecken property a configuration space approach

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Science China Mathematics 2017年第9期60卷 1561-1574页

作者： GONCALVeS Daciberg Lima GUASCHI John departamento de Matemdtica&IMe Universidade de Sao PauloSdo Paulo 05508-090Brazil Laboratoire de Mathematiques Nicolas Oresme UMR CNRS 6139 UNICAENNormandie UniversiteCS 1403214032 Caen Cedex 5France

Abstract In this paper, we explore the fixed point theory of n-vaiued maps using configuration spaces and braid groups, focusing on two fundamental problems, the Wecken property, and the computation of the Nielsen number. We show that the projective plane （resp. the 2-sphere S2） has the Wecken property for n-valued maps for all n ∈N （resp. all n ≥ 3）. In the case n = 2 and S2, we prove a partial result about the Wecken property. We then describe the Nielsen number of a non-split n-valued map φ ： X → X of an orientable, compact manifold without boundary in terms of the Nielsen coincidence numbers of a certain finite covering q：）→ X with a subset of the coordinate maps of a lift of the n-valued split map → q ： →X.

关键词： multivalued maps fixed points Wecken property Nielsen numbers braids configuration space

生物多样性热点地区内的群落预测:堆叠物种分布模型与森林清查数据对比

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Journal of Plant ecology 2023年第3期16卷 96-107页

作者： Victor Pereira Zwiener Valéria Andressa Alves Laboratório de ecologia e Biogeografia de plantas Departamento de BiodiversidadeSetor PalotinaUniversidade Federal do ParanáRua Pioneiro2153Jardim Dallas85950-000 PalotinaPRBrazil

鉴于当前气候变化和人类活动的影响,生物多样性的空间预测对其保护和修复至关重要。本文将不同堆叠物种分布模型(stacked species distribution models,S-SDMs)的预测结果与森林清查数据进行了比较,以评估这些S-SDMs模型能否捕获生物多... 详细信息

鉴于当前气候变化和人类活动的影响,生物多样性的空间预测对其保护和修复至关重要。本文将不同堆叠物种分布模型(stacked species distribution models,S-SDMs)的预测结果与森林清查数据进行了比较,以评估这些S-SDMs模型能否捕获生物多样性热点地区物种丰富度的新特性和地理分布及局部群落的组成。我们选取大西洋沿岸森林151处地点的1499个树种进行SDM模型构建,并利用4种模型堆叠方法重建植物群落。这43种方法分别为二进制SDM模型(bS-SDM)、由最小凸多边形裁剪得到的二进制SDM模型(bS-SDM-CROP)、受物种丰富度观测结果约束的堆叠SDM模型(cS-SDM)以及物种出现点的最小凸多边形(MCP)。我们从物种丰富度、组成、群落预测指标以及β多样性组分(物种嵌套和物种周转)等方面将各堆叠方法与局部群落进行对比。研究结果表明,所有S-SDM模型均捕获到了一般分布格局,其中bS-SDM-CROP模型最为简约。各堆叠模型预测得到的物种组成与局部群落的实际情况存在一定的差异,其中bS-SDM、bS-SDM-CROP和MCP模型呈现出嵌套格局,而物种周转在cS-SDM模型中最为显著。这些S-SDM模型在性能、遗漏率和记账错率方面的表现各不相同,对一些脆弱、濒危和极度濒危物种给出了错误预测。尽管与森林清查数据有差别,但这些S-SDM模型均捕获了与局部群落数据的部分差异,可以表征物种的潜在分布区。本研究的结论有助于S-SDM模型在粗尺度生物多样性整合与保护规划中的应用,但在生物高度多样性地区局部尺度上可能会得出错误的预测结果。

关键词：大西洋森林物种丰富度物种组成嵌套周转生态位建模

Bifunctional oxygen electrode cobalt–nickel sulfides catalysts originated from intercalated LDH precursors

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Journal of energy Chemistry 2022年第11期31卷 376-386,I0010页

作者： Xiaofei Gong Haihong Zhong Luis Alberto estudillo-Wong Nicolas Alonso-Vante Yongjun feng Dianqing Li State Key Laboratory of Chemical Resource engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029China departamento de Sociedad y Política Ambiental CIIEMADInstituto Politécnico NacionalCalle 30 de junio de 1520Alcaldía GAMC.P.07340 CDMXMexico IC2MP UMR-CNRS 7285University of PoitiersF-86073 Poitiers CedexFrance

Bimetallic cobalt-nickel sulfide nanoparticles anchored on S-,N-codoped holey carbon nanosheets(CoNiS-T@NCfs)with a hydrangea-like morphology,were synthesized via a confinement synthesis route,in which an intercalated LDH precursor was subjected to the interlayer-confined carbonization and host-layer *** phase transformation and structure evolution(e.g.,atom site occupancy,crystallite size,and cell volume)of the CoNi-S-T@NCfs electrocatalysts,as a function of sulfurization temperatures,were confirmed by X-ray diffraction and Rietveld *** sulfur vacancies effectively enhance the electrocatalytic activity,while the synergistic effect of(Co,Ni)7 S8 alloy and S,N-codoped carbon matrix facilitates the electron transfer and accelerates reaction kinetics,making CoNi-S-900@NCfs an efficient and stable bifunctional electrocatalyst for oxygen reduction reaction(ORR).The rich highvalence Co(Ⅲ)and Ni(Ⅲ)of CoNi-S-900@NCfs facilitates the in-situ transformation of the metal(oxy)hydroxides intermediates with high catalytic activity for oxygen evolution reaction(OeR).Thus,with a bifunctional parameter,Δe,of 0.75 V(e_(j=10,OeR)-e_(1/2,ORR)),this electrocatalyst slightly outperforms the state-of-the-art commercial Pt/C+RuO_(2)/C catalyst(Δe=0.76 V)in alkaline *** work demonstrates the influence that the sulfurization temperature has on the relationship between the structure and electrocatalytic performance of bimetallic sulfides prepared by the synthesis strategy using the intercalated LDH *** strategy can be extended to prepare other chalcogenides with binary or ternary transition metals.

关键词： Bimetallic sulfides Confinement synthesis LDHs ORR OeR

Submegahertz spectral width photon pair source based on fused silica microspheres

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Photonics Research 2021年第11期9卷 2237-2252页

作者： eRASTO ORTIZ-RICARDO CeSAR BeRTONI-OCAMPO MONICA MALDONADO-TeRRON ARTURO GARCIA ZURITA ROBeRTO RAMIReZ-ALARCON HeCTOR CRUZ RAMIReZ R.CASTRO-BeLTRAN ALfReD B.U’ReN Instituto de Ciencias Nucleares Universidad Nacional Autonoma de MexicoApartado Postal 70-54304510 MexicoD.F.Mexico Centro de Investigaciones en Optica A.C. Loma del Bosque 115Colonia Lomas del Campestre37150 LeonGuanajuatoMexico departamento de Ingenieria fisica Cuerpo Academico de Mecanica EstadisticaDivison de Ciencias e IngenieriasUniversidad de Guanajuato37150 LeonGuanajuatoMexico

High-efficiency submegahertz bandwidth photon pair generators will enable the field of quantum technology to transition from laboratory demonstrations to transformational applications involving information transfer from photons to *** spontaneous parametric processes are able to achieve high-efficiency photon pair generation,the spectral bandwidth tends to be relatively large,as defined by phase-matching *** solve this fundamental limitation,we use an ultrahigh quality factor(Q)fused silica microsphere resonant cavity to form a photon pair *** present the full theory for the spontaneous four-wave mixing(SfWM)process in these devices,fully taking into account all relevant source characteristics in our *** exceptionally narrow(down to kilohertz-scale)linewidths of these devices result in a reduction in the bandwidth of the photon pair generation,allowing submegahertz spectral bandwidth to be ***,using a pump source centered around 1550 nm,photon pairs with the signal and idler modes at wavelengths close to 1540 and 1560 nm,respectively,are *** herald a single idler-mode photon by detecting the corresponding signal photon,filtered via transmission through a wavelength division multiplexing channel of *** demonstrate the extraction of the spectral profile of a single peak in the single-photon frequency comb from a measurement of the signal–idler time of emission *** improvements in device design and experimental methods enabled the narrowest spectral width(Δν=366 k Hz)to date in a heralded single-photon source based on SfWM.

关键词： fused silica spectral

Raman probing carbon&aqueous electrolytes interfaces and molecular dynamics simulations towards understanding electrochemical properties under polarization conditions in supercapacitors

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Journal of energy Chemistry 2021年第9期30卷 279-292页

作者： Rafael Vicentini Leonardo M.Da Silva Débora V.franco Willian G.Nunes Juliane fiates Gustavo Doubek Luís f.M.franco Renato G.freitas Cristiano fantini Hudson Zanin Advanced energy Storage Division Carbon Sci-Tech LabsUniversity of CampinasAv Albert Einstein 400CampinasSP 13083-852Brazil department of Chemistry Federal University of Jequitinhonha and Mucuri’s ValleyRodovia MGT 367km 5835000Alto da Jacuba39.100-000 DiamantinaMGBrazil Advanced energy Storage Division Center for Innovation on New EnergiesLaboratory of Advanced BatteriesSchool of Chemical EngineeringUniversity of Campinas(UNICAMP)CampinasSP 13083-852Brazil department of Chemistry Federal University of Mato GrossoICET-UFMT78060-900 CuiabáMTBrazil departamento de física ICExUniversidade Federal de Minas GeraisBelo HorizonteMG 31270-901Brazil

Raman probing of carbon electrode and electrolyte under dynamic conditions is performed here using different aqueous electrolytes to elucidate the fundamental events occurring in electrochemical supercapacitor during charge–discharge *** areal capacitance ranges from 1.54 to 2.31μf cm^(-2)μm and it is determined using different *** findings indicate that the Helmholtz capacitance governs the overall charge-storage process instead of the space charge(quantum)capacitance commonly verified for HOPG electrodes in the range of~3 to 7μf cm^(-2).Molecular dynamics simulations are employed to elucidate the origin of the reversible Raman spectral changes during the charge–discharge processes.A correlation is verified between the reversible Raman shift and the surface excesses of the different ionic species.A theoretical framework is presented to relate the effect of the applied potential on the Raman shift and its correlation with the surface ionic *** is proposed that the Raman shift is governed by the interaction of solvated cations with graphite promoted by polarization *** is the first time that a comparative study on different aqueous electrolyte p H and cation ion size has been performed tracking the Raman spectra change under dynamic polarization conditions and contrasting with comprehensive electrochemistry and dynamic molecular simulations *** study shines lights onto the charge-storage mechanism with evidence of Kohn anomaly reduction in the carbon electrode during the reversible adsorption/desorption and insertion/extraction of ionic species.

关键词： defect reorganization in graphite Surface excess of charge Operando Raman studies electrical double-layer capacitors

碳基材料的Z型和S型异质结光催化清洁能源综述

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新型炭材料（中英文） 2024年第3期39卷 458-482页

作者： Sahil Rana Amit Kumar WANG Tong-tong Gaurav Sharma Pooja Dhiman Alberto García-Penas International Research Centre of Nanotechnology for Himalayan Sustainability(IRCNHS) Shoolini UniversitySolan173229India 西安建筑科技大学交叉创新研究院西安710055 departamento de Ciencia e Ingeniería de Materiales e Ingeniería Química(IAAB) Universidad Carlos Ⅲ de MadridLegan'es28911Spain

碳纳米管/纳米纤维、石墨烯、氧化石墨烯、还原氧化石墨烯、石墨炔、碳量子点和富勒烯等炭材料因具有高导电性、优异的稳定性和生物相容性等独特性能,近年来受到广泛关注。在炭材料中构建Z型和S型异质结已成为在能量转换应用中提高光催... 详细信息

碳纳米管/纳米纤维、石墨烯、氧化石墨烯、还原氧化石墨烯、石墨炔、碳量子点和富勒烯等炭材料因具有高导电性、优异的稳定性和生物相容性等独特性能,近年来受到广泛关注。在炭材料中构建Z型和S型异质结已成为在能量转换应用中提高光催化效率的一种有效策略。本文综述了光催化制氢和CO_(2)还原等清洁能源的基本原理,阐述了它们各自的机理和优势。此外,还讨论了不同类型的炭材料以及其中Z型和S型异质结的合成和构建,强调了它们在促进电荷分离、减少光生载流子复合损失和扩大光谱响应范围方面的作用。以太阳能燃料生产为重点,讨论和总结了碳基Z型和S型异质结在光催化制氢和还原CO_(2)方面的最新进展。最后,讨论了目前碳基光催化剂领域的瓶颈和挑战,并对该领域的未来发展提出了有价值的见解。

关键词：炭材料异质结 Z型 S型光催化氢能材料

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Sulfite activation by ZnO-encapsulated hydrogels for degradation of trimethylphenol

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Nano Research 2023年第10期16卷 12345-12356页

作者： Jiyuan Nai Yaning Han Shoudu Zhang Youxun Li Xiaowei Chen Ren’an Wu Li Wang Lei Jiang Heavy Oil State Laboratory and Center for Bioengineering and Biotechnology College of Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China departamento de Ciencia de los Materiales Ingeniería Metalúrgica y Química InorgánicaFacultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain Marine Science Research Institute of Shandong Province Qingdao 266104China CAS Key Laboratory of Separation Sciences for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Trimethylphenol is an organic toxic byproduct of industrial process,which is difficult to be eliminated through conventional degradation without harsh *** this work,a sulfite-based oxidation process activated by ZnO-embedded hydrogel was studied for the degradation of 2,4,6-trimethylphenols in the ambient *** ZnO/Na_(2)SO_(3)oxidative system can effectively degrade trimethylphenol via the generation of radicals such as SO_(4)^(-)·,OH·,and SO_(3)^(−)·.The presence of hydrogel matrix facilitates the distribution and recyclability of ZnO catalysts while maintaining high degradation kinetics and little leaching of metal *** suggest the promising potential of ZnO-hydrogel in wastewater treatment with good performance in terms of pH sensitivity,anion interference,recyclability,*** combination of ZnO catalysts,hydrogel,and sulfite-based advanced oxidation process may provide essential support for the current treatment of alkylated phenols with strong potential in the commercial scale-ups.

关键词： ZnO nanoparticles hydrogel 2 4 6-trimethylphenol nanocatalyst degradation sulfite

An Alternative Manifold for Cosmology Using Seifert fibered and Hyperbolic Spaces

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Applied Mathematics 2014年第6期5卷 1013-1028页

作者： Maria e.Mejía Reinaldo R.Rosa departamento de Matemáticas Universidad de GuadalajaraGuadalajaraMéxico Laboratório Associado de Computacao e Matemática Aplicada Instituto Nacional de Pesquisas EspaciaisSao Jose dos CamposBrasil

We propose a model with 3-dimensional spatial sections, constructed from hyperbolic cusp space glued to Seifert manifolds which are in this case homology spheres. The topological part of this research is based on Thurston’s conjecture which states that any 3-dimensional manifold has a canonical decomposition into parts, each of which has a particular geometric structure. In our case, each part is either a Seifert fibered or a cusp hyperbolic space. In our construction we remove tubular neighbourhoods of singular orbits in areas of Seifert fibered manifolds using a splice operation and replace each with a cusp hyperbolic space. We thus achieve elimination of all singularities, which appear in the standard-like cosmological models, replacing them by “a torus to infinity”. from this construction, we propose an alternative manifold for cosmology with finite volume and without friedmann-like singularities. This manifold was used for calculating coupling constants. Obtaining in this way a theoretical explanation for fundamental forces is at least in the sense of the hierarchy.

关键词： Topology Cosmology Thurston’s Theory Singularity-free