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Soil remediation potential of illite and Na-MMT for As and H_(3)AsO_(3) adsorption:Insights of ab initio calculations
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作者 LIU Zi-rou XU Xin-hang +2 位作者 ARMAGHANI Danial Jahed SPAGNOLI Dino QI Chong-chong 《Journal of Central South University》 2025年第5期1822-1837,共16页
Understanding the adsorption behavior of heavy metals and metalloids on clay minerals is essential for remediating heavy metal-contaminated soils.The adsorption of heavy metals and metalloids on illite(001)and sodium ... Understanding the adsorption behavior of heavy metals and metalloids on clay minerals is essential for remediating heavy metal-contaminated soils.The adsorption of heavy metals and metalloids on illite(001)and sodium montmorillonite(Na-MMT)(001)surfaces was investigated using first-principles calculations in this study,especially As atom and H_(3)AsO_(3) molecule.The adsorption energies of the As atom were−1.94 eV on the illite(001)and−0.56 eV on the Na-MMT(001),whereas,the adsorption energies of the H_(3)AsO_(3) molecule were−1.40 eV on illite(001)and−1.01 eV on Na-MMT(001).The above results indicate that the adsorption was more energetically favorable on illite(001).Additionally,compared to Na-MMT(001),there were more significant interactions between the atoms/molecules on the illite(001).After As atom and H_(3)AsO_(3) molecule adsorption,the electrons were transferred from mineral surface atoms to the adsorbates on both illite(001)and Na-MMT(001)surfaces.Moreover,the adsorption of As atom on illite(001)and Na-MMT(001)surfaces were more energy favorable compared to Hg,Cd,and Cr atoms.Overall,this work provides new insights into the adsorption behavior of As atoms and As molecules on illite and Na-MMT.The results indicate that illite rich soils are more prone to contamination by arsenic compared to soils primarily composed of Na-MMT minerals. 展开更多
关键词 soil contamination clay minerals ADSORPTION ab initio calculation ARSENIC
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Adsorption mechanism of multiple water molecules on tricalcium silicate (001) surface: A DFT study
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作者 Xinhang Xu Zirou Liu +2 位作者 Dino Spagnoli Danial Jahed Armaghani Chongchong Qi 《International Journal of Minerals,Metallurgy and Materials》 2025年第8期2034-2042,共9页
An in-depth understanding of the hydration mechanism of tricalcium silicate is an important basis for optimizing cement strength development.In this study,the adsorption of water molecules onto the M3-C3S(001)surface ... An in-depth understanding of the hydration mechanism of tricalcium silicate is an important basis for optimizing cement strength development.In this study,the adsorption of water molecules onto the M3-C3S(001)surface at different water coverage levels(θ=1/5,2/5,3/5,4/5,and 1)was investigated using first-principles calculations.The results demonstrate that the conclusions obtained for single water molecule adsorption cannot be fully applied to multiple water molecule adsorption.The total adsorption energies become more negative with increasing water coverage,while the average adsorption energy of each water molecule becomes more positive with increasing water coverage.The water–water interactions reduce the water–surface interactions and are responsible for the anticooperative adsorption of multiple water molecules onto M3-C_(3)S(001).The formation of Ca–OH(–Ca)bonds favors the detachment of Ca from co-valent oxygen,which reveals the significant role of dissociative adsorption.This work aims to extend the water adsorption study on M3-C3S(001)from single water molecule adsorption to multiple water molecule adsorption,providing more detailed insights into the initial water reaction on the C3S surface. 展开更多
关键词 cement hydration tricalcium silicate water molecules first-principles calculations ADSORPTION
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A bacterial type-II toxin-antitoxin-mediated gene amplification system in Saccharomyces cerevisiae
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作者 Samuel Evans Zeyu Lu +12 位作者 Liam McDonnell Will Anderson Francisco Peralta Tyson Watkins Hafna Ahmed Carlos Horacio Luna-Flores Thomas Loan Laura Navone Matt Trau Colin Scott Robert E*Speight Claudia E*Vickers Bingyin Peng 《Life Research》 2026年第1期5-16,共12页
Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we develop... Background:Tandem gene repeats naturally occur as important genomic features and determine many traits in living organisms,like human diseases and microbial productivities of target bioproducts.Methods:Here,we developed a bacterial type-II toxin-antitoxin-mediated method to manipulate genomic integration of tandem gene repeats in Saccharomyces cerevisiae and further visualised the evolutionary trajectories of gene repeats.We designed a tri-vector system to introduce toxin-antitoxin-driven gene amplification modules.Results:This system delivered multi-copy gene integration in the form of tandem gene repeats spontaneously and independently from toxin-antitoxin-mediated selection.Inducing the toxin(RelE)expressing via a copper(II)-inducible CUP1 promoter successfully drove the in-situ gene amplification of the antitoxin(RelB)module,resulting in~40 copies of a green fluorescence reporter gene per copy of genome.Copy-number changes,copy-number increase and copy-number decrease,and stable maintenance were visualised using the green fluorescence protein and blue chromoprotein AeBlue as reporters.Copy-number increases happened spontaneously and independent on a selection pressure.Increased copy number was quickly enriched through toxin-antitoxin-mediated selection.Conclusion:In summary,the bacterial toxin-antitoxin systems provide a flexible mechanism to manipulate gene copy number in eukaryotic cells and can be exploited for synthetic biology and metabolic engineering applications. 展开更多
关键词 tandem repeats gene amplification TOXIN-ANTITOXIN genetic dosage genome evolution
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Trade-offs between ion-conducting and mechanical properties: The case of polyacrylate electrolytes 被引量:3
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作者 Guoli Lu Yaojian Zhang +7 位作者 Jianjun Zhang Xiaofan Du Zhaolin Lv Junzhe Du Zhiming Zhao Yue Tang Jingwen Zhao Guanglei Cui 《Carbon Energy》 SCIE CSCD 2023年第2期24-60,共37页
Polymer electrolytes(PEs)have been long recognized as the key materials to enable energy-dense batteries and render flexible energy devices practically viable,owing to their chemical and mechanical reliability.However... Polymer electrolytes(PEs)have been long recognized as the key materials to enable energy-dense batteries and render flexible energy devices practically viable,owing to their chemical and mechanical reliability.However,much of their promise is yet to be realized.The roomtemperature ion conductivity of existing PEs still falls short of the implementation criterion of 10^(-4) S cm^(-1) on the promise of acceptable mechanical properties,thereby precluding their practical application.The twin but inversely related duties of polymers,that is,functioning as both an ion-conducting medium and a structural backbone,underlie this issue but are less elucidated systematically.The polyacrylate(PA)family is among promising polymer matrices on account of ester polarity,electrode compatibility,chemical tunability,and mechanical durability.The extensive applicability of PA in plasticized gels,dry solids,and emerging composites makes PA-based PEs representative to illustrate the trade-off between ion conduction and mechanical strength.We herein seek to outline the stated long-standing conflict exemplified by PA-based PEs,focusing on crucial strategies toward balancing and reconciling the two mutually exclusive properties,with the intention of offering designing guidelines for next-generation PEs. 展开更多
关键词 ionic conductivity lithium batteries mechanical properties POLYACRYLATE polymer electrolytes trade-offs
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Polymerization-induced microphase separation of polymer-polyoxometalate nanocomposites for anhydrous solid state electrolytes 被引量:1
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作者 Lu Liu Zicheng Wu +3 位作者 Zhao Zheng Qianjie Zhou Kun Chen Panchao Yin 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第9期4326-4330,共5页
Solid-state electrolytes(SSEs)with high ionic conductivity,mechanical stability,and high thermal stability,as well as the stringent requirement of application in high-temperature fuel cells and lithium-ion batteries i... Solid-state electrolytes(SSEs)with high ionic conductivity,mechanical stability,and high thermal stability,as well as the stringent requirement of application in high-temperature fuel cells and lithium-ion batteries is receiving increasing attention.Polymer nanocomposites(PNCs),combining the advantages of inorganic materials with those of polymeric materials,offer numerous opportunities for SSEs design.In this work,we report a facile and general one-pot approach based on polymerization-induced microphase separation(PIMS)to generate PNCs with bi-continuous microphases.This synthetic strategy transforms a homogeneous liquid precursor consisting of polyoxometalates(POMs,H_(3)PW_(12)O_(40),Li_(7)[V_(15)O_(36)(CO_(3))]),poly(ethylene glycol)(PEG)macro-chain-transfer agent,styrene and divinylbenzene monomers,into a robust and transparent monolith.The resulting POMs are uniformly dispersed in the PEG block(PEG/POM)to form a conducting pathway that successfully realizes the effective transfer of protons and lithium ions,while the highly cross-linked polystyrene domains(P(S-co-DVB))as mechanical support provide outstanding mechanical properties and thermal stability.As the POM loading ratio up to 35 wt%,the proton conductivity of nanocomposite reaches as high as 5.99×10^(-4) S/cm at 100℃ in anhydrous environment,which effectively promotes proton transfer under extreme environments.This study broadens the application of fuel cells and lithium-ion batteries in extreme environments. 展开更多
关键词 Solid-state electrolyte Microphase separation Bi-continuous structure POLYMER POLYOXOMETALATE
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Towards a multiscale model of colorectal cancer 被引量:1
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作者 Ingeborg MM van Leeuwen Carina M Edwards +1 位作者 Mohammad Ilyas Helen M Byrne 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第9期1399-1407,共9页
Colorectal cancer (CRC) is one of the best characterised cancers, with extensive data documenting the sequential gene mutations that underlie its development. Complementary datasets are also being generated describing... Colorectal cancer (CRC) is one of the best characterised cancers, with extensive data documenting the sequential gene mutations that underlie its development. Complementary datasets are also being generated describing changes in protein and RNA expression, tumour biology and clinical outcome. Both the quantity and the variety of information are inexorably increasing and there is now an accompanying need to integrate these highly disparate datasets. In this article we aim to explain why we believe that mathematical modelling represents a natural tool or language with which to integrate these data and, in so doing, to provide insight into CRC. 展开更多
关键词 Intestinal epithelium Crypt fission APC mutations Mathematical modelling Stem cell niche Wnt signalling
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Dual Effects of Interfacial Interaction and Geometric Constraints on Structural Formation of Poly(butylene terephthalate)Nanorods
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作者 Kaichao Wang Ziwei Lai +6 位作者 Jiaman Huang Haiying Li Ziying Liang Junhao Liang Xing Ouyang Xiaoguang Li Yan Cao 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2022年第6期700-708,共9页
When the size of the material is smaller than the size of the molecular chain,new nanostructures can be formed by crystallizing polymers in nanoporous alumina.However,the effect of pore wall and geometric constraints ... When the size of the material is smaller than the size of the molecular chain,new nanostructures can be formed by crystallizing polymers in nanoporous alumina.However,the effect of pore wall and geometric constraints on polymer nanostructures remains unclear.In this study,we demonstrate three new restricted nanostructures{upright-,flat-and tilting-ring}in polybutylene terephthalate(PBT)nanorods prepared from nanoporous alumina.The dual effects of geometrical constraints and interfacial interactions on the formation of PBT nanostructures were investigated for the first time by using X-ray diffraction and Cerius^(2) modeling packages.Under weak constraints,the interaction between pore wall and the PBT rings is dominant and the ring plane tends to be parallel to the pore wall and radiate outward to grow the upright-ring crystals.Surprisingly,in strong 2D confinement,a structural formation reversal occurs and geometrical constraints overpower the effect of pore wall.Rings tend to pile up vertically or obliquely along the long axis of the rod,so the flat-and tilting-ring crystals are predominate in the constrained system.In principle,our study of the nanostructure formation based on the geometrical constraints and the pore wall interfacial effects could provide a new route to manipulate the chain assembly at the nanoscale,further improving the performance of polymer nanomaterial. 展开更多
关键词 Cylindrical confinement Poly(butylene terephthalate) NANORODS Geometry constraints Interfacial interaction
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Laser-induced Fluorescence Spectroscopy of Uranium Monofluoride
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作者 Xi-lin Bai You-long Wang Timothy C.Steimle 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第5期754-763,I0011,共11页
The laser-induced fluorescence excitation spectra of uranium monofluoride have been recorded in the range of17000-19000 cm^(-1) using twodimensional spectroscopy.High resolution dispersed fluorescence spectra and time... The laser-induced fluorescence excitation spectra of uranium monofluoride have been recorded in the range of17000-19000 cm^(-1) using twodimensional spectroscopy.High resolution dispersed fluorescence spectra and time-resolved fluorescence spectroscopy were also recorded.Three rotationally resolved bands were intensively analyzed,and all bands were found to be derived from the ground state X(1)4.5 with a rotational constant of 0.23421 cm^(-1).The low-lying electronic states were observed near 435 and 651 cm^(-1) in the dispersed fluorescence spectra,which were assigned as?′=3.5 and 2.5,respectively.The vibrational constants for the X(1)4.5 and X(1)3.5 states were calculated.The branching ratios of the dispersed fluorescence spectra for the[18.62]3.5,[17.72]4.5,and[17.65]4.5 states were reported.Radiative lifetime of332(9)ns,825(49)ns,and 433(15)ns for the[18.62]3.5,[17.72]4.5,and[17.65]4.5 states were obtained by fitting the time-resolved fluorescence spectroscopy,respectively.Transition dipole moments were performed using the branching ratios and the radiative lifetimes. 展开更多
关键词 Laser-induced fluorescence Uranium monofluoride Two-dimensional spectroscopy
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Spherical Packing Superlattices in Self-Assembly of Homogenous Soft Matter:Progresses and Potentials
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作者 Yuchu Liu Huanyu Lei +8 位作者 Qing-Yun Guo Xianyou Liu Xinghan Li Yuean Wu Weiyi Li Wei Zhang Geng Xin Liu Xiao-Yun Yan Stephen Z.D.Cheng 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第5期607-620,I0005,共15页
The construction of complex superlattices using homogenous soft matter has great potential for the bottom-up fabrication of complex,nanoscale structures.This topic is not only interested in scientific exploring for ne... The construction of complex superlattices using homogenous soft matter has great potential for the bottom-up fabrication of complex,nanoscale structures.This topic is not only interested in scientific exploring for new concepts of supramolecular crystals with nanometer in sizes,which is about thousand times larger in volumes than those of normal crystals,but also practically important to provide construction principles of metamaterials which are artificially structured materials for controlling and manipulating light,sound,and other physical behaviors.These systems have fast assembly kinetics and convenient processing procedures,making them ideal for large-scale superlattice production.In this perspective,we focus on recent developments in the construction of complex spherical packing superlattices using homogenous soft self-assemblies.We discuss the general mechanism of those formations of supramolecular motifs and provide an overview of the spherical packing superlattices self-assembled by homogenous soft matters based on different volume asymmetry.Additionally,we outline the potentials of utilizing this approach in constructing novel superlattices as well as its future challenges. 展开更多
关键词 Soft matter SELF-ASSEMBLY Spherical packing phases SUPERLATTICE Bottom-up construction
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Laser-induced fluorescence experimental spectroscopy and theoretical calculations of uranium monoxide
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作者 Xi-Lin Bai Xue-Dong Zhang +1 位作者 Fu-Qiang Zhang Timothy C Steimle 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期245-252,共8页
As a model molecule of actinide chemistry,UO molecule plays an important role in understanding the electronic structure and chemical bonding of actinide-containing species.We report a study of the laser-induced fluore... As a model molecule of actinide chemistry,UO molecule plays an important role in understanding the electronic structure and chemical bonding of actinide-containing species.We report a study of the laser-induced fluorescence spectra of the U^(16)O and U^(18)O using two-dimensional spectroscopy.Several rotationally resolved excitation spectra were investigated.Accurate molecular rotational constants and equilibrium internuclear distances were reported.Low-lying electronic states information was extracted from high resolution dispersed fluorescence spectra and analyzed by the ligand field theory model.The configuration of the ground state was determined as U^(2+)(5 f^(3)7 s)O^(2-).The branching ratios,and the vibrational harmonic and anharmonic parameters were also obtained.Radiative lifetimes were determined by recording the timeresolved fluorescence spectroscopy.Transition dipole moments were calculated using the branching ratios and the radiative lifetimes.These findings were elucidated by using quantum-chemical calculations,and the chemical bonding was also analyzed.The findings presented in this work will enrich our understanding of actinide-containing molecules. 展开更多
关键词 laser-induced fluorescence two-dimensional spectroscopy density functional theory
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Synthesis and photophysical properties of donor–acceptor system based bipyridylporphyrins for dye-sensitized solar cells
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作者 Preeyanut Duanglaor Preecha Thiampanya +2 位作者 Taweesak Sudyoadsuk Vinich Promarak Buncha Pulpoka 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第6期779-785,共7页
Bipyridylporphyrin derivatives possessing a porphyrin moiety as the electron donor and bipyridyl moiety as the electron-acceptor were designed and synthesized for dye-sensitized solar cells (DSSCs). The photo- physi... Bipyridylporphyrin derivatives possessing a porphyrin moiety as the electron donor and bipyridyl moiety as the electron-acceptor were designed and synthesized for dye-sensitized solar cells (DSSCs). The photo- physical and electrochemical properties were investigated by absorption spectrometry and cyclic voltam- metry. Density functional theory (DFT) was employed to study electron distribution. From the photovoltaic performance measurements, a maximum conversion efficiency (η) of 0.38% was achieved based on the bipyridylporphyrin ruthenium dye A7 (Jsc = 1.33 mA/cm^2, Voc = 0.45 V, FF = 0.64) under 1,5 irradiation (100 mW/cm^2). 展开更多
关键词 Dye-sensitized solar cells (DSSCs) Porphyrin Ruthenium complex Energy
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NucleoCraft:The Art of Stimuli-Responsive Precision in DNA and RNA Bioengineering
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作者 Lu Yu Liangxiao Chen +2 位作者 Deeksha Satyabola Abhay Prasad Hao Yan 《Biomedical Engineering Frontiers》 2024年第1期132-150,共19页
Recent advancements in DNA and RNA bioengineering have paved the way for developing stimuli-responsive nanostructures with remarkable potential across various applications.These nanostructures,crafted through sophisti... Recent advancements in DNA and RNA bioengineering have paved the way for developing stimuli-responsive nanostructures with remarkable potential across various applications.These nanostructures,crafted through sophisticated bioengineering techniques,can dynamically and precisely respond to both physiological and physical stimuli,including nucleic acids(DNA/RNA),adenosine triphosphate,proteins,ions,small molecules,pH,light,and temperature.They offer high sensitivity and specificity,making them ideal for applications such as biomarker detection,gene therapy,and controlled targeted drug delivery.In this review,we summarize the bioengineering methods used to assemble versatile stimuli-responsive DNA/RNA nanostructures and discuss their emerging applications in structural biology and biomedicine,including biosensing,targeted drug delivery,and therapeutics.Finally,we highlight the challenges and opportunities in the rational design of these intelligent bioengineered nanostructures. 展开更多
关键词 DNA nanostructures BIOSENSING targeted drug delivery bioengineering techniquescan RNA nanostructures physiological physical stimuliincluding BIOENGINEERING nucleic acids dna rna adenosine triphosphateproteinsionssmall moleculesphlightand
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Acceptance of COVID-19 vaccine and its related determinants in Nigeria:An online survey
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作者 Eyiuche D Ezigbo Seyi S Enitan +14 位作者 Esther N Adejumo Abiodun E Durosinmi Richard Y Akele Michael O Dada Grace E Itodo Abah M Idoko Okeoghene M Edafetanure-Ibeh Edwin N Okafor Adedeji A Abdulsalam Oyekan I Oyedoyin Polit U Yelpoji Ogunwola O Opeyemi Ogbuji S Nmesomachi Adesola O Oyekale Chisom B Onyeji 《World Journal of Virology》 2024年第4期89-110,共22页
BACKGROUND Vaccine hesitancy is a major challenge in the fight against the coronavirus disease 2019(COVID-19)pandemic.Identifying the sociodemographic factors associated with vaccine acceptance among Nigerians is cruc... BACKGROUND Vaccine hesitancy is a major challenge in the fight against the coronavirus disease 2019(COVID-19)pandemic.Identifying the sociodemographic factors associated with vaccine acceptance among Nigerians is crucial for improving vaccine uptake.AIM To assess the acceptance rate of COVID-19 vaccine and its related determinants among Nigerians.METHODS An online cross-sectional survey(observational study)was conducted between February 2021 and May 2021,using a questionnaire hosted on SurveyMonkey.The invitation to take part in the poll was sent out to participants through social networking platforms.A logistic regression was used to determine which sociodemographic factors were associated with vaccine acceptance constructs.RESULTS A total of 1800 persons responded to the survey,a larger proportion of whom were males(53.9%)and within the age group of 21-30 years(29.4%)and earned an average income of less than$500 per month(43.3%).Only 0.56%of participants had a high perceived risk of COVID-19 infection,while only 1.11%had a perceived risk of dying from COVID-19.The perception rate of the COVID-19 vaccine among participants was 51.1%,while the acceptance rate was 63.9%.There was no significant association between the COVID-19 vaccine acceptance rate and related determinants assessed,particularly age(χ²=3.049,P=0.550),sex(χ²=0.102,P=0.749),average income(χ²=3.802,P=0.875),and religion(χ²=2.819,P=0.420).Participants with chronic conditions demonstrated a higher acceptance rate compared to the general population.CONCLUSION Despite the positive perception observed and substantial vaccine acceptance rate among the study participants,more public health interventions are still needed to enhance vaccine acceptability in Nigeria. 展开更多
关键词 ACCEPTANCE COVID-19 Determinants Hesitancy NIGERIANS Online survey VACCINE
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CO_(2) adsorption behaviour on β-C_(2)S(111) and (100) surfaces: Implications for carbon sequestration in cementitious materials
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作者 Chongchong Qi Zirou Liu +2 位作者 Dino Spagnoli Danial Jahed Armaghani Xinhang Xu 《International Journal of Minerals,Metallurgy and Materials》 2025年第9期2109-2118,共10页
Understanding the differences in CO_(2)adsorption in cementitious material is critical in mitigating the carbon footprint of the construction industry.This study chose the most common β-C_(2)S phase in the industry a... Understanding the differences in CO_(2)adsorption in cementitious material is critical in mitigating the carbon footprint of the construction industry.This study chose the most common β-C_(2)S phase in the industry as the cementitious material,selecting the β-C_(2)S(111)and β-C_(2)S(100)surfaces for CO_(2)adsorption.First-principles calculations were employed to systematically compare the CO_(2)ad-sorption behaviors on both surfaces focusing on adsorption energy,adsorption configurations,and surface reconstruction.The comparis-on of CO_(2)and H2O adsorption behaviors on the β-C_(2)S(111)surface was also conducted to shed light on the influence of CO_(2)on cement hydration.The adsorption energies of CO_(2)on the β-C_(2)S(111)and β-C_(2)S(100)surfaces were determined as-0.647 and-0.423 eV,respect-ively,suggesting that CO_(2)adsorption is more energetically favorable on the β-C_(2)S(111)surface than on the β-C_(2)S(100)surface.The ad-sorption energy of H2O on the β-C_(2)S(111)surface was-1.588 eV,which is 0.941 eV more negative than that of CO_(2),implying that β-C_(2)S tends to become hydrated before reacting with CO_(2).Bader charges,charge density differences,and the partial density of states were ap-plied to characterize the electronic properties of CO_(2)and H2O molecules and those of the surface atoms.The initial Ca/O sites on the β-C_(2)S(111)surface exhibited higher chemical reactivity due to the greater change in the average number of valence electrons in the CO_(2)ad-sorption.Specifically,after CO_(2)adsorption,the average number of valence electrons for both the Ca and O atoms increased by 0.002 on the β-C_(2)S(111)surface,while both decreased by 0.001 on the β-C_(2)S(100)surface.In addition,due to the lower valence electron number of O atoms,the chemical reactivity of O atoms on the β-C_(2)S(111)surface after H2O adsorption was higher than the case of CO_(2)adsorption,which favors the occurrence of further reactions.Overall,this work assessed the adsorption capacity of the β-C_(2)S surface for CO_(2)mo-lecules,offering a strong theoretical foundation for the design of novel cementitious materials for CO_(2)capture and storage. 展开更多
关键词 CO_(2)adsorption cementitious materials first-principles calculations carbon sequestration
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Cirrhotic portal hypertension: From pathophysiology to novel therapeutics 被引量:42
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作者 Lakmie S Gunarathne Harinda Rajapaksha +2 位作者 Nicholas Shackel Peter W Angus Chandana B Herath 《World Journal of Gastroenterology》 SCIE CAS 2020年第40期6111-6140,共30页
Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients with cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance a... Portal hypertension and bleeding from gastroesophageal varices is the major cause of morbidity and mortality in patients with cirrhosis. Portal hypertension is initiated by increased intrahepatic vascular resistance and a hyperdynamic circulatory state. The latter is characterized by a high cardiac output, increased total blood volume and splanchnic vasodilatation, resulting in increased mesenteric blood flow. Pharmacological manipulation of cirrhotic portal hypertension targets both the splanchnic and hepatic vascular beds. Drugs such as angiotensin converting enzyme inhibitors and angiotensin Ⅱ type receptor 1 blockers, which target the components of the classical renin angiotensin system(RAS), are expected to reduce intrahepatic vascular tone by reducing extracellular matrix deposition and vasoactivity of contractile cells and thereby improve portal hypertension. However, these drugs have been shown to produce significant offtarget effects such as systemic hypotension and renal failure. Therefore, the current pharmacological mainstay in clinical practice to prevent variceal bleeding and improving patient survival by reducing portal pressure is non-selective-blockers(NSBBs). These NSBBs work by reducing cardiac output and splanchnic vasodilatation but most patients do not achieve an optimal therapeutic response and a significant proportion of patients are unable to tolerate these drugs.Although statins, used alone or in combination with NSBBs, have been shown to improve portal pressure and overall mortality in cirrhotic patients, further randomized clinical trials are warranted involving larger patient populations with clear clinical end points. On the other hand, recent findings from studies that have investigated the potential use of the blockers of the components of the alternate RAS provided compelling evidence that could lead to the development of drugs targeting the splanchnic vascular bed to inhibit splanchnic vasodilatation in portal hypertension. This review outlines the mechanisms related to the pathogenesis of portal hypertension and attempts to provide an update on currently available therapeutic approaches in the management of portal hypertension with special emphasis on how the alternate RAS could be manipulated in our search for development of safe, specific and effective novel therapies to treat portal hypertension in cirrhosis. 展开更多
关键词 Portal hypertension Cirrhosis Intrahepatic vascular resistance Hyperdynamic circulatory state Splanchnic vasodilatation Portal blood flow Non-selective betablockers Alternate renin angiotensin system
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Hydration reactivity difference between dicalcium silicate and tricalcium silicate revealed from structural and Bader charge analysis 被引量:2
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作者 Chongchong Qi Xinhang Xu Qiusong Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第2期335-344,共10页
Cement hydration is the underlying mechanism for the strength development in cement-based materials.The structural and electronic properties of calcium silicates should be elucidated to reveal their difference in hydr... Cement hydration is the underlying mechanism for the strength development in cement-based materials.The structural and electronic properties of calcium silicates should be elucidated to reveal their difference in hydration reactivity.Here,we comprehensively comparedβ-C_(2)S and M_(3)-C_(3)S and investigated their structural properties and Bader charge in the unit cell,during surface reconstruction and after single water adsorption via density functional theory.We identified different types of atoms inβ-C_(2)S and M_(3)-C_(3)S by considering the bonding characteristics and Bader charge.We then divided the atoms into the following groups:forβ-C_(2)S,Ca and O atoms divided into two and four groups,respectively;for M_(3)-C_(3)S,Ca,O,and Si atoms divided into four,four,and three groups,respectively.Results revealed that the valence electron distribution on the surface was more uniform than that on the unit cell,indicating that some atoms became more reactive after surface relaxation.During water adsorption,the electrons ofβ-C_(2)S and M_(3)-C_(3)S were transferred from the surface to the adsorbed water molecules through position redistribution and bond formation/breaking.On this basis,we explained whyβ-C_(2)S and M_(3)-C_(3)S had activity differences.A type of O atom with special bond characteristics(no O–Si bonds)and high reactivity existed in the unit cell of M_(3)-C_(3)S.Bader charge analysis showed that the reactivity of Ca and O atoms was generally higher in M_(3)-C_(3)S than inβ-C_(2)S.Ca/O atoms had average valence electron numbers of6.437/7.550 inβ-C_(2)S and 6.481/7.537 in M_(3)-C_(3)S.Moreover,the number of electrons gained by water molecules in M_(3)-C_(3)S at the surface was higher than that inβ-C_(2)S.The average variations in the valence electrons of H_(2)O onβ-C_(2)S and M_(3)-C_(3)S were 0.041 and 0.226,respectively.This study further explains the differences in the hydration reactivity of calcium silicates and would be also useful for the design of highly reactive and environmentally friendly cements. 展开更多
关键词 calcium silicates Portland cement hydration reactivity first-principle calculations
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Strategies for efficient photothermal therapy at mild temperatures:Progresses and challenges 被引量:1
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作者 Peng Gao Hui Wang Yiyun Cheng 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第2期575-586,共12页
Photothermal therapy(PTT), typically ablates tumors via hyperthermia generated from photothermal agents(PTAs) under laser irradiation, has attracted great attentions in the past decades. Unfortunately,longstanding, fr... Photothermal therapy(PTT), typically ablates tumors via hyperthermia generated from photothermal agents(PTAs) under laser irradiation, has attracted great attentions in the past decades. Unfortunately,longstanding, frequent and high-power density laser irradiations are needed to maintain the hyperthermal status(>50 ℃) for efficient therapy, which will damage the skin and nearby healthy tissues. Suppressing cancer cells with a mild temperature elevation is more attractive and feasible for PTT. Recently,low-temperature photothermal therapy(LTPTT), which could inhibit tumor under mild hyperthermia, has been widely investigated by researchers. Herein, we systematically summarized the strategies to achieve LTPTT. Diverse PTAs including organic and inorganic materials reported for LTPTT were introduced. The established strategies for LTPTT were intensively described. Finally, the challenges as well as future perspectives in this field were discussed. 展开更多
关键词 Photothermal therapy Mild hyperthermia Photothermal agents NANOMEDICINE Tumor targeted therapy
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Caspase-cleaved cytokeratin-18 and tumour regression in gastro-oesophageal adenocarcinomas treated with neoadjuvant chemotherapy
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作者 Khaleel R Fareed Irshad N Soomro +4 位作者 Khalid Hameed Arvind Arora Dileep N Lobo Simon L Parsons Srinivasan Madhusudan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第16期1915-1920,共6页
AIM:To examine cytokeratin-18(CK-18) and caspasecleaved CK-18 expression in tumours and correlate with clinicopathological outcomes including tumour regression grade(TRG) response.METHODS:Formalin-fixed human gastro-o... AIM:To examine cytokeratin-18(CK-18) and caspasecleaved CK-18 expression in tumours and correlate with clinicopathological outcomes including tumour regression grade(TRG) response.METHODS:Formalin-fixed human gastro-oesophageal cancers were constructed into tissue microarrays.The first set consisted of 122 gastric/gastro-oesophageal cancer cases not exposed to neoadjuvant chemotherapy and the second set consisted of 97 gastric/gastrooesophageal cancer cases exposed to pre-operative platinum-based chemotherapy.Expression of CK-18 and caspase-cleaved CK-18 was investigated using immunohistochemistry.RESULTS:CK18 was commonly expressed in gastrooesophageal tumours(92.6%).Fifty-six point seven percent of tumours previously exposed to neoadjuvant chemotherapy were positive for caspase-cleaved CK-18 expression compared to only 24.6% of tumours not previously exposed to neoadjuvant chemotherapy(P = 0.009).In patients who received neoadjuvant chemotherapy,caspase-cleaved cytokeratin-18 expression correlated with favourable TRG response(TRG 1,2 or 3,P = 0.043).CONCLUSION:This is the largest study to date of CK-18 and caspase-cleaved CK-18 expression in gastrooesophageal tumours.We provide the first evidence that caspase-cleaved CK-18 predicts tumour regression with neoadjuvant chemotherapy. 展开更多
关键词 Tumour regression grade Gastro-oesophageal cancers CHEMOTHERAPY Full length cytokeratin-18 Caspase-cleaved cytokeratin-18
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Branching out: Nitrogen-dependent modulation of strigolactone signaling 被引量:1
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作者 Andrew J.Tuckey Mark T.Waters 《Molecular Plant》 2025年第1期14-16,共3页
Strigolactones (SLs) are carotenoid-derived plant compounds that stimulate the germination of root-parasitic weeds. Why a host plant should produce such detrimental signals remained unclear until exuded SLs were shown... Strigolactones (SLs) are carotenoid-derived plant compounds that stimulate the germination of root-parasitic weeds. Why a host plant should produce such detrimental signals remained unclear until exuded SLs were shown to also encourage symbioses with arbuscular mycorrhizal fungi. Shortly after this discovery, SLs were found to act internally as endogenous phytohormones to regulate numerous traits, most prominently shoot branching, or “tillering” in cereal crops (Gomez-Roldan et al., 2008;Umehara et al., 2008). 展开更多
关键词 TRAITS plant
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HOXB13 in cancer development:molecular mechanisms and clinical implications
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作者 Jian Zhang Ying Ju Li +6 位作者 Bo Peng Xuna Yang Miao Chen Yongxing Li Hengbin Gao Haitao Li Ji Zheng 《Frontiers of Medicine》 2025年第3期439-455,共17页
The transcription factor HOXB13 plays crucial roles in cancer development.HOXB13 is abnormally expressed in most cancers,which makes it a valuable therapeutic target for cancer therapy.The level of HOXB13 differs sign... The transcription factor HOXB13 plays crucial roles in cancer development.HOXB13 is abnormally expressed in most cancers,which makes it a valuable therapeutic target for cancer therapy.The level of HOXB13 differs significantly between healthy and cancer tissues,which indicates that the level of HOXB13 is closely related to carcinogenesis.The regulatory network mediated by HOXB13 in cancer proliferation,metastasis,and invasion has been systematically investigated.Moreover,HOXB13 variants play distinct roles in different cancers and populations.By understanding the molecular mechanisms and mutation features of HOXB13,we provide a comprehensive overview of carcinogenesis networks dependent on HOXB13.Finally,we discuss advancements in anticancer therapy targeting HOXB13 and the roles of HOXB13 in drug resistance to molecular-targeted therapies,which serves as a foundation for developing HOXB13-targeted drugs for clinical diagnosis and cancer therapies. 展开更多
关键词 HOXB13 CARCINOGENESIS epigenetic regulation SNPS clinical treatment
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