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Diet and epigenetics in colon cancer

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World Journal of Gastroenterology 2009年第3期15卷 257-263页

作者： minna nystrm marja mutanen Department of Biological and Environmental Sciences GeneticsUniversity of HelsinkiFI-00014 HelsinkiFinland Department of Applied Chemistry and microbiology Division of NutritionUniversity of HelsinkiFI-00014 HelsinkiFinland

Over the past few years, evidence has accumulated indicating that apart from genetic alterations, epigenetic alterations, through e.g. aberrant promoter methylation, play a major role in the initiation and progression of colorectal cancer (CRC). Even in the hereditary colon cancer syndromes, in which the susceptibility is inherited dominantly, cancer develops only as the result of the progressive accumulation of genetic and epigenetic alterations. Diet can both prevent and induce colon carcinogenesis, for instance, through epigenetic changes, which regulate the homeostasis of the intestinal mucosa. Food-derived compounds are constantly present in the intestine and may shift cellular balance toward harmful outcomes, such as increased susceptibility to mutations. There is strong evidence that a major component of cancer risk may involve epigenetic changes in normal cells that increase the probability of cancer after genetic mutation. The recognition of epigenetic changes as a driving force in colorectal neoplasia would open new areas of research in disease epidemiology, risk assessment, and treatment, especially in mutation carriers who already have an inherited predisposition to cancer.

关键词： Colon cancer Diet DNA methylation Epigenetics Nutrition

Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela Henrik J.Persson magnus Ekstrom Sean P.Healey Zhiqiang Yang Johan Holmgren Eva Lindberg Kenneth nystrom Emanuele Papucci Patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson Ronald E.mcRoberts Department of Forest Resource management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and Natural Resource management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias model-based inference Design-based inference

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Nanocellulose-assisted preparation of electromagnetic interference shielding materials with diversified microstructure

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Smartmat 2022年第4期3卷 582-607页

作者： Zhihui Zeng Jing Qiao Runa Zhang Jiurong Liu Gustav nyström Key Laboratory for Liquid-Solid Structural Evolution and Processing of materials School of Materials Science and EngineeringShandong UniversityJinanChina School of mechanical Engineering Shandong UniversityJinanChina Laboratory for Cellulose and Wood materials Swiss Federal Laboratories for Materials Science and Technology(Empa)DübendorfSwitzerland Department of Health Sciences and Technology ETH ZürichZürichSwitzerland

Sustainable and renewable nanocellulose attracts more and more attention in various fields due to its high strength-to-weight ratio,small diameter,large aspect ratio,and abundant functional *** excellent properties and structural characteristics enabled a great potential of nanocellulose for efficient interactions with functional nanomaterials such as carbon nanotube,graphene,transition metal carbides/nitrides(mXenes),and metal nanoparticles,which is beneficial for preparing high-performance electromagnetic interference(EmI)*** review the advances in the nanocelluloseassisted preparation of composite films and aerogels for EmI shielding *** nanocellulose-based composites are evaluated in terms of their EmI shielding performance and the shielding mechanisms,including conduction,polarization,and multiple reflections are *** addition to the constituent structure and contents,we highlight the significance of the microstructure design in enhancing the EmI shielding performance of the nanocellulose-based EmI ***,the current challenges and outlook for these fascinating nanocellulose-based EmI shielding composites are discussed.

关键词： aerogels electromagnetic interference shielding film microstructure design nanocellulose nanocomposite

Positron Study of Origin of Thermoelastic martensiteStabilization for a Cu-Zn-Al Alloy

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Journal of materials Science & Technology 1996年第5期12卷 377-380页

作者： Wang, JC Shao, ZC Zhang, GL Zheng, WH Yu, fh Chen, LY Gu, m ACAD SINICA SHANGHAI INST NUCL RESSHANGHAI 201800PEOPLES R CHINA TONGJI UNIV DEPT PHYSSHANGHAI 200092PEOPLES R CHINA

A series of Cu-23Zn-10Al (at pet) alloy specimens subjected to different heat-treatment processes have been studied by means of Doppler broadening technique of positron annihilation combined with mechanical test. Results show that the mechanism of quenched-in vacancies, instead of the other suggested ones, plays a dominant role in thermoelastic martensite stabilization of Cu-based shape memory alloy. Knowing the character of the movement of quenched-in vacancies and eliminating them as rapidly as possible are the basis for further optimizing heat-treatment process to obtain desired shape memory performance.

关键词： Shape memory effect

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Bioinspired cellulose-integrated mXene-based hydrogels for multifunctional sensing and electromagnetic interference shielding

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Interdisciplinary materials 2022年第4期1卷 495-506页

作者： Jingjiang Wei Chenglong Zhu Zhihui Zeng Fei Pan Fuqiang Wan Liwen Lei Gustav nyström Zhengyi Fu State Key Laboratory of Advanced Technology for materials Synthesis and Processing Wuhan University of TechnologyWuhanHubeiPR China Laboratory for Cellulose and Wood materials Swiss Federal Laboratories for Materials Science and Technology(Empa)DübendorfSwitzerland Key Laboratory for Liquid-Solid Structural Evolution and Processing of materials School of Material Science and EngineeringShandong UniversityJinanShandongPR China Laboratory for Biointerfaces Swiss Federal Laboratories for Materials Science and Technology(Empa)St.GallenSwitzerland Department of Health Science and Technology ETH ZürichZürichSwitzerland

Bioinspired hydrogels are complex materials with distinctive properties comparable to biological *** exceptional sensitivity to various external stimuli leads to substantial application potential in wearable smart ***,these multifaceted hydrogels are often challenging to be combined with pattern customization,stimulus responsiveness,self-healing,and ***,inspired by mussel secretions,a printable,self-healing,and biocompatible mXene-based composite hydrogel was designed and prepared by incorporating Ti3C2Tx mXene nanosheets into the hydrogel framework through the chelation of calcium ions(Ca2+)with polyacrylic acid and cellulose nanofibers at alkaline *** biocompatible conductive hydrogel exhibited sensitivity(gauge factor of 2.16),self-healing(within 1 s),recognition,and adhesion,distinguishing it as an ideal candidate for wearable multifunctional sensors toward strain sensing,vocal sensing,signature detection,and morse code ***,the multifunctional hydrogel manifested efficient electromagnetic interference shielding properties(reaching more than 30 dB at a thickness of 2.0 mm),protecting electronics and humans from electromagnetic radiation and ***,the presented work represents a versatile strategy for developing environmentally friendly conductive hydrogels,demonstrating the perspectives of intelligent hydrogels for multifunctional applications.

关键词： cellulose nanofiber electromagnetic interference shielding hydrogel mXene sensor

Some Alkaline Rocks of Shansi Province, N. China

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地质学报 1947年 85-92页

作者： ERIK T. nystrm Sino-Swedish Research Institute

Shansi province covers the mountainous territory W. and S.W. of Peiping and its capital Taiyuan is situated approximately in the centre of the province and at a distance of about 400 km. in a southwestern direction from the old capital. In the 20’s and 30’s numerous areas of highly alkaline rocks were discovered in Shansi by the Geological Survey of China and the Sino-Swedish Research

关键词： China Some Alkaline Rocks of Shansi Province

Claudin-11 and occludin are major contributors to Sertoli cell tight junction function, in vitro

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Asian Journal of Andrology 2016年第4期18卷 620-626页

作者： mark J mcCabe Caroline fh Foo marcel E Dinger Peter m Smooker Peter G Stanton male Fertility Regulation Laboratory Hudson Institute of Medical Research Monash Medical Centre Clayton Victoria 3168 Australia School of Applied Sciences Royal Melbourne Institute of Technology University Bundoora Victoria 3088 Australia Kinghorn Centre for Clinical Genomics Garvan Institute of Medical Research Darlinghurst New South Wales 2010 Australia St Vincent's Clinical School UNSW Sydney New South Wales 2052 Australia.

The Sertoli cell tight junction （T J） is the key component of the blood-testis barrier, where it sequesters developing germ cells undergoing spermatogenesis within the seminiferous tubules. Hormonally regulated claudin-11 is a critical transmembrane protein involved in barrier function and its murine knockout results in infertility. We aimed to assess quantitatively the significance of the contribution of claudin-11 to TJ function, in vitro, using siRNA-mediated gene silencing. We also conducted an analysis of the contribution of occludin, another intrinsic transmembrane protein of the TJ. Silencing of claudin-11 and/or occludin was conducted using siRNA in an immature rat Sertoli cell culture model. Transepithelial electrical resistance was used to assess quantitatively TJ function throughout the culture. Two days after siRNA treatment, cells were fixed for immunocytochemical localization of junction proteins or lyzed for RT-PCR assessment of mRNA expression. Silencing of claudin-11, occludin, or both resulted in significant decreases in TJ function of 55% （P 〈 0.01）, 51% （P 〈 0.01）, and 62% （P 〈 0.01）, respectively. Data were concomitant with significant decreases in mRNA expression and marked reductions in the localization of targeted proteins to the Sertoli cell TJ. We provide quantitative evidence that claudin-11 contributes significantly （P 〈 0.01） to Sertoli cell TJ function in vitro. Interestingly, occludin, which is hormonally regulated but not implicated in infertility until late adulthood, is also a significant （P 〈 0.01） contributor to barrier function. Our data are consistent with in vivo studies that clearly demonstrate a role for these proteins in maintaining normal TJ barrier structure and function.

关键词： blood-testis barrier claudin-11 occludin Sertoli cell tight junction siRNA

THE CHEmICAL STRUCTURE OF CELASTRINE FROm CELASTRUS FLAGELLARIS

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Chinese Chemical Letters 1995年第8期6卷 679-680页

作者： Wang, mA Wang, m Liu, J Chen, fh Hong, SL ma, LB Beijing Agr Univ Dept Appl Chem Beijing 100094 Peoples R China Beijing Inst microchem Beijing 100091 Peoples R China

A now sesquiterpenoid named as celastrine was isolated from the seed oil of Celastrus flagellaris Rupr. Its structure was determined as 1 alpha ,6 beta ,8 alpha ,13-tetraacetoxy-9 alpha -benzoyloxy-beta -dihydroagarofuran by UV, IR, mS and NmR(H-1 NmR, C-13 NmR, H-1-H-1 COSY, H-1-C-13 COSY, NOESY and HmBC) spectra.

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ALKALINE INTRUSIVES OF LUTINGSHAN AND CH'IAOSHAN IN ***

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地质学报 1933年 312-332+334-343页

作者： E.T.nystrm S.L.TSAO

In recent years several localities of highly alkaline rocks have been dis-covered in Shansi by the National Geological Survey of China and the Sino-Swedish Research *** results of investigation in this line up to 1927... 详细信息

关键词： ALKALINE INTRUSIVES OF LUTINGSHAN AND CH’IAOSHAN IN S.SHANSI CH