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A product version of the Hilton-Milner-Frankl theorem

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Science China Mathematics 2024年第2期67卷 455-474页

作者： peter Frankl Jian Wang Alfréd Rényi Institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| < t, | ∩ {G : G ∈ G}| < t. In the present paper,we determine... 详细信息

two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| t, | ∩ {G : G ∈ G}| t. In the present paper,we determine the maximum product of the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-Frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial

采用图像信息学方法研究三维支架中细胞的信号通路

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上海交通大学学报 2014年第9期48卷 1257-1262页

作者：郭进 tZERANIS Dimitrios S SO peter t C 魏勋斌复旦大学化学系生物医学研究院上海200433 麻省理工学院生物工程系美国剑桥021390 上海交通大学Med-X研究院上海200030

通过慢病毒介导的短发夹RNA对成纤维细胞的转化生长因子β(tGF-β)信号通路进行干扰,采用双光子荧光显微成像技术并结合基于细胞-细胞外基质三维系统的图像信息学方法,研究了植于多孔胶原蛋白支架中成纤维细胞分化过程的tGF-β信号通路... 详细信息

通过慢病毒介导的短发夹RNA对成纤维细胞的转化生长因子β(tGF-β)信号通路进行干扰,采用双光子荧光显微成像技术并结合基于细胞-细胞外基质三维系统的图像信息学方法,研究了植于多孔胶原蛋白支架中成纤维细胞分化过程的tGF-β信号通路.结果表明,在介导成纤维细胞分化的过程中,生长因子tGF-β1比tGF-β3发挥的作用更大,在tGF-β1介导的成纤维细胞分化过程中,蛋白SMAD1和SMAD3通过不同方式也发挥了重要作用.所得结果与通过生化或遗传学方法的结果相吻合.

关键词：图像信息学双光子荧光显微成像转化生长因子β 成纤维细胞多孔胶原蛋白支架

Memoirs of a Survivor: Masuji Ibuse's Black Rain

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外国文学研究 2005年第2期27卷 128-132页

作者： peter Messent professor of modern American literature at the University of Nottingham in England

this paper examines the motif of survival in Masuji Ibuse’s Hiroshima novel Black Rain (1969). It explores narrative technique, figurative language, voice and t one, and the gap between thought and feeling, to show h... 详细信息

关键词：日本广岛原子弹小说叙事技巧《暴雨》 Masuji Ibuse

Clearcuts and related secondary dieback undermine the ecological effectiveness of FSC certification in a boreal forest

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Ecological Processes 2020年第1期9卷 108-116页

作者： Jeanette Silvin Blumröder Monika t.Hoffmann Olga Ilina Susanne Winter peter R.Hobson Pierre L.Ibisch Centre for Econics and Ecosystem Management Eberswalde University for Sustainable DevelopmentAlfred-Moeller-Str.116225 EberswaldeGermany Petrozavodsk State University Lenina st.33185000 PetrozavodskRussia Karelian Nature Conservancy(SPOK) PetrozavodskRussia WWF Germany Reinhardtstr1810117 BerlinGermany Centre for Econics and Ecosystem Management Writtle University CollegeLordship RoadWrittle Chelmsford Essex CM13RRUK

Background:Over the last 25 years,the prominent forest certification system established by the Forest Stewardship Council(FSC)has used by many companies worldwide for claiming responsible forest *** objectives of the Russian National FSC standard to decrease the size of clearcuts and the retention of forest elements such as residual seed trees need on-site validation to proof the effectiveness of *** assess the ecological impacts of harvesting practices and benefits of FSC certification,we geospatially compared logging activities with and without FSC *** a sample area covering approximately 3,000 km^(2) in the east of the Russian Arkhangelsk Region,we used available data on tree cover loss and satellite images to assess secondary impacts of clearcuttings on adjacent remnant forests and to quantify the logging ***,the size and structure as well as the density of skidding trails of ten specific clearcuttings located within the sample area were surveyed using satellite images and in the field observation to delineate the boundaries of clearcuts and forested remnants within the ***:We found a significant increase of small-scale tree cover loss in the proximity of the *** dieback is possibly linked to the scale and intensity of logging in the *** the investigated clearcuts,FSC failed to reduce the size,to increase the retention of forest remnants including seed trees on logged areas,and to maintain larger tracts of undisturbed ground and soil compared to clearcuts that were logged before they received ***:trees and forest remnants remaining inside an increasingly stressed forest ecosystem matrix may not resist further harvesting-related and climate change-induced stresses and ***-scale clearcuttings seem to have negative impacts even in adjacent forests and undermine the ecological effectiveness of FSC certification in the study *** Russi

关键词： Ecological effectiveness Impact assessment Forest certification Sustainable forestry

Differential Kinematic Encoding of Saccades and Smooth-pursuit Eye Movements by Fastigial Neurons

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Neuroscience Bulletin 2022年第8期38卷 927-932页

作者： Zongpeng Sun peter W.Dicke peter thier School of Psychology Shaanxi Normal UniversityXi’an710062China Department of Cognitive Neurology Hertie Institute for Clinical Brain Research72076TübingenGermany

Dear Editor,Saccades and smooth-pursuit eye movements(SPEMs)are two categories of eye movements with very different kinematics,in particular very different acceleration and velocity ranges,differences that have contributed to the notion of largely segregated underlying neuronal *** instance,it has been suggested that distinct wellsegregated pools of oculomotor vermis(OMV)Purkinje cells(PCs)are specialized for the fine-tuning of the relevant kinematic parameters characterizing each of them.

关键词： pursuit specialized instance

the Dynamics of Online Purchase Visits： Inertia or Switching？

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Frontiers of Business Research in China 2016年第1期10卷 1-18页

作者： Zelin Zhang Xia Wang peter t. L. Popkowski Leszczyc Xiao Zuo School of Business Renmin U.niversity of China Beijing 100872 China School of Business University of Alberta Edmonton AB T6G 2R6 Canada Baidu Marketing Research Institute Beijing 100085 China

this paper studies the dynamics of online purchase patterns, focusing on the impact of the channel used on conversion probability, as well as the transition of channel use over time. A novel data set from a major Chinese online travel agency is used for analysis, consisting of four months of data with 24,337 store visits through three types of channels： direct visit, search advertising and referral. Results of a Bayesian multinomial logit model show that the search channel significantly affects consumers＇ conversion probability, and show a high degree of inertia in channel use. this finding contrasts sharply with suggestions of previous research that most future purchases will converge to the direct-visit channel.

关键词： conversion probability direct visit search engine referral

Seasonality of PSII thermostability and water use e ffi ciency of in situ mountainous Norway spruce(Picea abies)

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Journal of Forestry Research 2023年第1期34卷 197-208页

作者： peter Petrik Anja Petek-Petrik Alena Konopkova peter Fleischer Srdjan Stojnic Ina Zavadilova Daniel Kurjak Global Change Research Institute Czech Academy of SciencesBrnoCzech Republic Department of Vegetation Ecology Institute of Botany CASBrnoCzech Republic Faculty of Forestry Technical University of ZvolenZvolenSlovakia Institute of Forest Ecology Slovak Academy of SciencesZvolenSlovakia Institute of Lowland Forestry and Environment University of Novi SadNovi SadSerbia

the stability of monocultural,even-aged spruce forests at lower altitudes in Central Europe is seriously threatened by the prospects of global climate *** thermostability and water use efficiency of their photo synthetic apparatus might play a vital role in their successful *** this study,photo systemⅡ(PSⅡ)performance(OJIP transient,rapid light curves)and thermostability were analyzed in Norway spruce(Picea abies(L.)Karst.)throughout the growing season of the exceptionally warm year 2018(May-September)in the Western Carpathians,*** measurements were accompanied by analysis of pigment concentrations in the *** addition,gas-exchange temperature curves were produced weekly from June until September to obtain intrinsic water use *** the beginning of the growing season,needles exposed to heat stress showed significantly higher basal fluorescence and lower quantum yield,performance index,critical temperature thresholds of PSII inactivation and nonphotochemical yield in comparison to other *** overall thermostability(heat-resistance)of PSII peaked in July and August,reflected in the lowest basal fluorescence and the highest quantum yield of PSII,critical temperature thresholds and yield of non-photochemical quenching under heat ***,the ratio between chlorophyll and carotenoids was the highest in August and had a positive impact on PSII ***,the high-temperature intrinsic water use efficiency was significantly higher during July and August than in *** show that15-year-old trees of Picea abies at 840 m *** acclimative seasonal responses of PSII thermostability and intrinsic water use efficiency during an exceptionally warm *** results suggest that mountainous *** at lower altitudes can acclimate their photosynthetic apparatus to higher temperatures during summer.

关键词： Heat stress Photosynthesis Non-photochemical quenching Pigments Intrinsic water use efficiency

Rectal nitric oxide as biomarker in the treatment of inflammatory bowel disease: Responders versus nonresponders

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World Journal of Gastroenterology 2006年第21期12卷 3386-3392页

作者： tryggve Ljung Sofie Lundberg Mark Varsanyi Catharina Johansson peter t Schmidt Max Herulf Jon O Lundberg Per M Hellstr(o|¨)m Department of Gastroenterology and Hepatology Karolinska University Hospital Site SolnaStockholmSweden Department of Physiology and Pharmacology Karolinska Institutet StockholmSweden

AIM： to explore rectal nitric oxide （NO） as biomarker of treatment response in ulcerative colitis （UC） and Crohn＇s disease （CD）, and examine relationships between rectal NO, mucosal expression of NO synthases （NOS）, and pro-inflammatory cytokines. MEtHODS： twenty-two patients with UC and 24 with CD were monitored during steroid treatment. Rectal NO levels were measured and clinical activities were assessed on days 1, 3, 7 and 28. Mucosal presence of NOS and pro-inflammatory cytokines were analyzed by immunohistochemistry and Rt-PCR. RESULtS： Active UC and CD displayed markedly increased rectal NO levels （10950 ± 7610 and 5 040 ± 1 280 parts per billion （ppb）, respectively） as compared with the controls （154 ± 71 ppb, P 〈 0.001）. Rectal NO correlated weakly with disease activity in both UC and CD （r = 0.34 for UC and r = 0.48 for CD, P 〈 0.01）. In 12 patients, a steroid-refractory course led to colectomy. these patients had only slightly increased NO levels （UC： 620 ± 270 ppb; CD： 1260 ± 550 ppb） compared to those with a therapeutic response （UC： 18860 ± 530 ppb, P 〈 0.001, CD： 10060 ± 3200 ppb, P 〈 0.05）. CONCLUSION： Rectal NO level is a useful biomarker of treatment response in IBD as low NO levels predicts a poor clinical response to steroid treatment.

关键词： Crohn's disease CytokJnes Nitric oxide Steroids Ulcerative colitis

In Situ Etching for total Control Over Axial and Radial Nanowire Growth

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Nano Research 2010年第4期3卷 264-270页

作者： Magnus t.Borgström Jesper Wallentin Johanna trägårdh peter Ramvall Martin Ek LReine Wallenberg Lars Samuelson Knut Deppert Solid State Physics Lund UniversityBox 118S-22100LundSweden Polymer&Materials Chemistry/nCHREM Lund UniversityS-22100 LundSweden H.H.Wills Physics Laboratory University of BristolTyndall AvenueBristol BS81TLUnited Kingdom

We report a method using in situ etching to decouple the axial from the radial nanowire growth pathway,independent of other growth *** a wide range of growth parameters can be explored to improve the nanowire properties without concern of tapering or excess structural defects formed during radial *** demonstrate the method using etching by HCl during InP nanowire *** improved crystal quality of etched nanowires is indicated by strongly enhanced photoluminescence as compared to reference nanowires obtained without etching.

关键词： MOVPE nanowire growth in situ etching photoluminescence