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Global well-posedness for the 2D critical dissipative quasi-geostrophic equation

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Science china Mathematics 2007年第4期50卷 485-494页

作者： zhi-fei zhang school of Mathematical Sciences,{3., beijing 100871, china school of Mathematical Sciences Peking University Beijing 100871 China

We study the initial value problem for the 2D critical dissipative quasi-geostrophic equation. We prove the global existence for small data in the scale invariant Besov spaces ? p,1 2/p , 1 ? p ? ∞. In particular, for p = ∞, our result does not impose any regularity on the initial data. Our proofs are based on an exponential decay estimate of the semigroup $e^{{ - t\kappa ( - \Delta )}^{\alpha}} $ and the use of space-time Besov spaces.

关键词： quasi-geostrophic equation Besov space Littlewood-Paley decomposition well-posedness 3.Q3.

Cellular senescence and metabolic reprogramming:Unraveling the intricate crosstalk in the immunosuppressive tumor microenvironment

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Cancer Communications 2024年第9期44卷 929-966页

作者： Fusheng zhang Junchen Guo Shengmiao Yu Youwei Zheng Meiqi duan Liang Zhao YihanWang zhi Yang Xiaofeng Jiang Department of General Surgery The Fourth Affiliated Hospital of China Medical UniversityShenyangLiaoningP.R.China Department of Hepatobiliary and Pancreatic Surgery Peking University First HospitalBeijingP.R.China Department of Radiology The Fourth Affiliated Hospital of China Medical UniversityShenyangLiaoningP.R.China Outpatient Department The Fourth Affiliated HospitalChina Medical UniversityShenyangLiaoningP.R.China

The intrinsic oncogenic mechanisms and properties of the tumor microenvironment(TME)have been extensively *** features of the TME include metabolic reprogramming,hypoxia,chronic inflammation,and tumor *** studies suggest that senescence-associated secretory phenotypes that mediate intercellular information exchange play a role in the dynamic evolution of the ***,hypoxic adaptation,metabolic dysregulation,and phenotypic shifts in immune cells regulated by cellular senescence synergistically contribute to the development of an immunosuppressive microenvironment and chronic inflammation,thereby promoting the progression of tumor *** review provides a comprehensive summary of the processes by which cellular senescence regulates the dynamic evolution of the tumor-adapted TME,with focus on the complex mechanisms underlying the relationship between senescence and changes in the biological functions of tumor *** available findings suggest that components of the TME collectively contribute to the progression of tumor *** potential applications and challenges of targeted cellular senescence-based and combination therapies in clinical settings are further discussed within the context of advancing cellular senescence-related research.

关键词： cellular senescence metabolic reprogramming hypoxia chronic inflammation immunosuppressive tumor microenvironment tumor-targeted therapy

Inclination of Broad Line Region in Narrow Line and Broad Line Seyfert 1 Galaxies

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Chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 487-500页

作者： Tian-zhi zhang and Xue-Bing WuDepartment of Astronomy, school of Physics,{3., beijing 100871 Department of Astronomy School of Physics Peking University Beijing 100871

The sizes of the Broad Line Region (BLR) of some Seyfert 1 galaxies and nearby quasars can be determined by the reverberation mapping method. Combining with the observed FWHM of Hbeta emission line and assuming that the motion of BLR clouds is virialized, the black hole masses of these objects have been estimated. However, this method strongly depends on the poorly-understood geometry and inclination of the BLR. On the other hand, a tight correlation between the black hole mass and the bulge velocity dispersion was recently found for both active and nearby inactive galaxies. This may provide another method, independent of the BLR geometry, for estimating the black hole mass. Using this method for estimating the black hole mass and combining with the measured BLR size and FWHM of Hbeta emission line, we derived the BLR inclination angles for 20 Seyfert 1 galaxies under the assumption that the BLR is disk-like. The derived inclination angles agree well with those derived previously by fitting the UV continuum and Hbeta emission line profiles. Adopting a relation between the FWHMs of [OIII]lambda5007 forbidden line and the stellar velocity dispersion, we also estimated the BLR inclinations for 50 narrow line Seyfert 1 galaxies (NLS1s). We found that the inclinations of broad Line Seyfert 1 galaxies (BLS1s) axe systematically greater than those of NLS1s, which seldom exceed 3.degrees. This may be an important factor that leads to the differences between NLS1s and BLS1s if the BLR of NLS1s is really disk-like.

关键词： galaxies : active galaxies : nuclei galaxies : Seyfert

Confined gas transport in low-dimensional materials

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International Journal of Smart and Nano Materials 2024年第1期15卷 127-164页

作者： Hongwei duan Zeyu Zhuang Jing Yang Shengping zhang Luda Wang National Key Laboratory of Advanced Micro and Nano Manufacture Technology School of Integrated CircuitsPeking UniversityBeijingChina Academy for Advanced Interdisciplinary Studies and Center for Nanochemistry Beijing Science and Engineering Center for NanocarbonsPeking UniversityBeijingChina beijing Advanced Innovation Center for Integrated Circuits BeijingChina Technology Innovation Center of Graphene Metrology and Standardization for State Market Regulation Beijing Graphene instituteBeijingChina

Gas transport under confinement exhibits a plethora of physical and chemical phenomena that differ from those observed in bulk media,owing to the deviations of continuum description at the molecular *** biological systems,gas channels play indispen-sable roles in various physiological functions by regulating gas transport across cell ***,investigating gas trans-port under such confinement is crucial for comprehending cellular physiological ***,leveraging these underlying mechanisms can enable the construction of bioinspired artificial nanofluidic devices with tailored gas transport properties akin to those found in biological *** review provides a comprehensive summary of confined gas transport mechanisms,focusing on the unique effects arising from ***,we categorize nanoconfinement spaces based on dimensionality to elucidate their control over gas transport ***,we highlight the potential of bioinspired smart gas membranes that mimic precise modulation of transportation observed in *** conclude,we present a concise outlook on the challenges and opportunities in this rapidly expanding field.

关键词： Nanofluidics gas transport transport mechanism low-dimensional materials smart membranes

On the local wellposedness of 3.D water wave problem with vorticity

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Science china Mathematics 2007年第8期50卷 1065-1077页

作者： Ping zhang~1 zhi-fei zhang~2 1 Academy of Mathematics and Systems Science,Chinese Academy of Sciences,{3. 100080,china 2 school of Mathematical Sciences,peking university,{3. 100871,china Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China school of Mathematical Sciences Peking University Beijing 100871 China

In this article, we first present an equivalent formulation of the free boundary problem to 3.D incompressible Euler equations, then we announce our local wellposedness result concerning the free boundary problem in Sobolev space provided that there is no self-intersection point on the initial surface and under the stability assumption that $\frac{{\partial p}}{{\partial n}}(\xi )\left| {_{t = 0} } \right. \leqslant - 2c_0 < 0$ being restricted to the initial surface.

关键词： water-waves free boundary incompressible Euler equations primary 3.Q3. 76B03 secondary 3.J67 3.L80

Cisplatin-induced premature senescence with concomitant reduction of gap junctions in human fibroblasts

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Cell Research 2004年第1期14卷 60-66页

作者： Wei ZHAO, Zhong Xiang LIN, zhi Qian zhang peking university {3. of Oncology, and beijing Institute for Cancer Research, beijing 10003., china. Lin ZX Peking Univ Sch Oncol Beijing 100034 Peoples R China

To examine the role of gap junctions in cell senescence, the changes of gap junctions in cisplatin-induced premature senescence of primary cultured fibroblasts were studied and compared with the replicative senescent human fibroblasts. Dye transfer assay for gap junction function and immunofluorescent staining for connexin 43.protein distribution were done respectively. Furthermore, cytofluorimetry and DAPI fluorescence staining were performed for cell cycle and apoptosis analysis, p53.gene expression level was detected with indirect immunofluorescence. We found that cisplatin (10 mM) treatment could block cell growth cycle at G1 and induced premature senescence. The premature senescence changes included high frequency of apoptosis, elevation of p53.expression, loss of membranous gap junctions and reduction of dye-transfer capacity. These changes were comparable to the changes of replicative senescence of human fibroblasts. It was also concluded that cisplatin could induce premature senescence concomita

关键词： cisplatin premature senescence gap junction intercellular communication connexin 43 fibroblasts.

Exploring anomalous nanofluidic transport at the interfaces

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Droplet 2024年第2期3卷 34-57页

作者： Shengping zhang Ruiyang Song Haiou Zeng Ningran Wu Hongwei duan Luda Wang National Key Laboratory of Advanced Micro and Nano Manufacture Technology School of Integrated CircuitsPeking UniversityBeijingChina Academy for Advanced Interdisciplinary Studies and Center for Nanochemistry Beijing Science and Engineering Center for NanocarbonsPeking UniversityBeijingChina Technology Innovation Center of Graphene Metrology and Standardization for State Market Regulation Beijing Graphene InstituteBeijingChina beijing Advanced Innovation Center for Integrated Circuits BeijingChina

Transport of ions and water is essential for diverse physiological activities and industrial *** the dimension approaches nano and even angstrom scale,ions and water exhibit anomalous behaviors that differ significantly from the *** of the key reasons for these distinctive behaviors is the prominent influence of surface effects and related transport properties occurring at the interface under such(sub)***,exploring nanofluidic transport at the interfaces could not only contribute to unraveling the intriguing ion and water transport behaviors but also facilitate the development of nanofluidic devices with tunable mass transport for practical *** this review,we focus on three crucial interfaces governing ion and water transport,namely liquid–gas interface,liquid–solid interface,and liquid–liquid interface,with emphasis on elucidating their intricate interfacial structures and critical roles for nanofluidic transport ***,potential applications associated with liquid–gas,liquid–solid,and liquid–liquid interfaces are also ***,we present a perspective on the pivotal roles of interfaces on nanofluidics,as well as challenges in this advancing field.

关键词： transport interface anomalous

Efficacy and safety of transvaginal mesh repair in a cohort with a minimum of 10-year follow-up

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Science china(Life Sciences) 2024年第5期67卷 1061-1068页

作者： zhibo zhang Jianbin Guo Weijie Tian Ye zhang Yuelun zhang Tianshu Sun Jiali duan Xinmiao Bao Yuan Wang Yang Ye Qianqian Gao Honghui Shi Abraham Nick Morse Juan Chen Lan Zhu Departmentof Obstetrics and Gynecology Peking Union MedicalCollege HospitalChinese Academyof Medical Sciences&Peking Union MedicalCollegeNational Clinical Research Center for Obstetricand Gynecologic DiseasesBeijing 100730China Department of Gynecology Guizhou Provincial People’s HospitalMedical College of Guizhou UniversityGuiyang 550002China Department of Obstetrics and Gynecology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000China Medical Research Center Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Medical Doctor Program Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Pathology Peking Union Medical College HospitalBeijing 100730China Tufts university school of Medicine Boston MA 02111USA

Although transvaginal mesh(TVM)repair is no longer used in some countries,long-term outcomes after TVM surgery are of great importance ***,reports with follow-up>10 years are ***,this study aimed to report outcomes in a prospective cohort with at least 10 years of *** with stageⅢ–Ⅳsymptomatic prolapse were approached consecutively from 2008 to 2013.at one tertiary *** main outcome measure was symptomatic *** outcomes included anatomic failure,recurrence,patient satisfaction,complications,and *** Kaplan-Meier curve was used to estimate the cumulative failure *** the 121 patients enrolled in the study,103.85.1%)completed a median follow-up of 11 *** estimated probability rates of symptomatic and anatomic failure were 17.6%and 8.8%in 11 years,*** estimated incidence of symptomatic failure increased by 8.2%between 5 and 11 years;however,the corresponding rate for anatomic failure was 3.7%.The most common complication was vaginal mesh exposure,and its estimated probability increased from 19.3.to 28.4%from 5 to 11 years,*** trimming resolved 80.0%of vaginal *** patients did not report decreased overall *** with vaginal mesh exposure requiring>3.office procedures or mesh removal in the operating room(5.8%by 11 years)had lower satisfaction rates(P3.3.,and 94.2%,*** results of this study implied that TVM treatment gradually increased the symptomatic failure rate but provided durable anatomical support of the vaginal *** mesh exposure was common in women who were largely not sexually active;however,80%of the cases could be managed in the outpatient clinic,which did not affect patient satisfaction.

关键词： complication efficacy long-term follow-up pelvic organ prolapse safety transvaginal mesh

Renin-angiotensin system inhibitors prescriptions in Chinese hospitalized chronic kidney disease patients

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World Journal of Clinical Cases 2024年第17期12卷 3061-3075页

作者： Chun zhang zhi-Yu duan Sa-Sa Nie Zhou zhang Xin-Ru Guo Chao-Yang zhang Jing Dong Guang-Yan Cai Department of Nephrology The First Medical CentreChinese PLA General HospitalBeijing 100853China school of Medicine Nankai UniversityTianjin 300071China National Engineering Laboratory for Medical Big Data Application Technology Chinese PLA General HospitalBeijing 100853China

BACKGROUND Many guidelines have recommended renin-angiotensin system inhibitors(RASI)as the first-line treatment for patients with chronic kidney disease(CKD).We studied RASI prescription trends from 2010 to 2019,and analyzed the characteristics associated with RASI prescription in Chinese hospitalized CKD *** To study the prescription of renin angiotensin system inhibitors in hospitalized patients with CKD in *** It was retrospectively,cross-sectional reviewed RASI prescriptions in hospitalized CKD patients in china from 2010 to *** prescribing trends were analyzed from 2010 to 2019,and bivariate and multivariate logistic regression analyses were conducted to identify characteristics associated with RASI *** A total of 3.090 CKD patients were included,with 10043.28.6%)RASI *** these patients,18919(53.9%)met the criteria for RASI treatments based on the 2012 kidney disease:Improving global outcomes *** these,7246(3..3.)patients received RASI *** prescriptions showed an initial rapid increase from 2011 to 2012,reached its peak around 2015 and 2016,and then exhibited a subsequent slight decreasing *** bivariate and multivariate analyses showed that several characteristics,including the male gender,age less than 60-year-old,nephrology department admission,lower CKD stage,history of hypertension or diabetes,proteinuria,glomerulonephritis as the CKD etiology,and non-acute kidney injury were associated with RASI *** The frequency of RASI prescriptions showed an initial increase but a slight decreasing trend in more recent *** patients with certain characteristics such as elderly age,advanced disease stage,surgery department admission,or acute kidney injury were less likely to receive RASI *** the application of RASI in hospitalized CKD patients is *** actual clinical practice needs to be *** development of related research

关键词： Chronic kidney disease Renin-angiotensin system inhibitors Prescriptions Adherence