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Aneuploidy in pluripotent stem cells and implications for cancerous transformation

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Protein & Cell 2014年第8期5卷 569-579页

作者： Jie Na Duncan Baker Jing Zhang peter w. Andrews Ivana Barbaric School of Medicine Tsinghua University Beijing 100084 China Sheffield Diagnostic Genetic Services Sheffield Children's Hospital Sheffield S10 2TH UK Centre for Stem Cell Biology Department of Biomedical Science The University of Sheffield Sheffield S10 2TN UK

Owing to a unique set of attributes, human pluripotent stem cells （hPSCs） have emerged as a promising cell source for regenerative medicine, disease modeling and drug discovery. Assurance of genetic stability over long term maintenance of hPSCs is pivotal in this endeavor, but hPSCs can adapt to life in culture by acquiring non-random genetic changes that render them more robust and easier to grow. In separate studies between 12.5% and 34% of hPSC lines were found to acquire chromosome abnormalities over time, with the incidence increasing with passage number. The predominant genetic changes found in hPSC lines involve changes in chromosome number and structure （particularly of chromosomes 1, 12, 17 and 20）, remi- niscent of the changes observed in cancer cells. In this review, we summarize current knowledge on the causes and consequences of aneuploidy in hPSCs and highlight the potential links with genetic changes observed in human cancers and early embryos. we point to the need for comprehensive characterization of mechanisms underpinning both the acquisition of chromosomal abnormalities and selection pressures, which allow mutations to persist in hPSC cultures. Elucidation of these mechanisms will help to design culture conditions that minimize the appearance of aneuploid hPSCs. Moreover, aneuploidy in hPSCs may provide a unique platform to analyse the driving for- ces behind the genome evolution that may eventually lead to cancerous transformation.

关键词： human pluripotent stem cells (hPSCs),culture adaptation aneuploidy cancer genetic changes

Labial tip sensilla of Blissus leucopterus leucopterus （Hemiptera： Blissidae）： Ultrastructure and behavior

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Insect Science 2008年第3期15卷 271-275页

作者： Gerald T. Baker Xiong Chen peter w.K. Ma Department of Entomology and Plant Pathology Box 9775 Mississippi State University Mississippi State MS 39762 USA

The cuticular sensory receptors that are found on the apex of the labium of hemipterans play an important role in their feeding behavior. In this study we describe the ultrastructure, number, and distribution of sensilla on the labium apex of the chinch bug, Blissus leucopterus leucopterus. Each apical field of sensilla on the labium contains 11 uniporous peg sensilla and one sensillum chaeticum. The uniporous peg sensilla are innervated by 4-5 bipolar neurons that send dendrites in the lumen of each peg. Three neurons are associated with each sensillum chaeticum, two neurons have dendrites in the lumen of the sensillum, and the third dendrite ends in a tubular body at the base of the sensillum. Behavioral tests that involve chemical blockage of the sensory receptors show the importance of the labial sensilla in feeding behavior. Both morphological and behavioral evidence indicate that the labial sensilla have a chemosensitive function.

关键词： behavioral tests chinch bug electron microscopy labial sensilla Nmethylmaleimide

Heterodyne Standing-wave Interferometer with Improved Phase Stability

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Nanomanufacturing and Metrology 2021年第3期4卷 190-199页

作者： Ingo Ortlepp Jens-peter Zollner Ivo w.Rangelow Eberhard Manske Institute of Process Measurement and Sensor Technology Technische Universitat IlmenauEhrenbergstraBe 2998693 IlmenauGermany Microelectronic and Nanoelectronic Systems Group Technische Universitat IlmenauIlmenauGermany Nanoscale Systems Group Technische Universitat IlmenauIlmenauGermany

This paper describes a standing-wave interferometer with two laser sources of different wavelengths,diametrically opposed and emitting towards each *** resulting standing wave has an intensity profile which is moving with a constant velocity,and is directly detected inside the laser beam by two thin and transparent photo *** first sensor is at a fixed position,serving as a phase reference for the second one which is moved along the optical axis,resulting in a frequency shift,proportional to the *** phase difference between both sensors is evaluated for the purpose of interferometric length measurements.

关键词： Standing wave Interferometer Heterodyne Ultrathin photo diode

Fabrication and Tissue Anchoring Performance of Nylon and Polypropylene Barbed Surgical Sutures

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Journal of Donghua University(English Edition) 2013年第5期30卷 391-393页

作者：丛慧 ROE Simon MENTE peter RUFF Gregory KING w Martin College of Textiles North Carolina State University College of Veterinary Medicine North Carolina State University Department of Biomedical Engineering North Carolina State University Vilcom Circle Chapel Hill College of Textiles Donghua University

Barbed surgical sutures have attracted worldwide attention in recent years. The plurality of barbs projecting out and penetrating into surrounding tissue eliminates the need for tying a knot. In the current study,nylon and polypropylene( PP) barbed sutures with two different barb geometries designed to anchor in porcine skin and tendon tissues were fabricated by a specially designed mechanical cutting machine. The tensile properties were compared between the barbed and unbarbed control sutures. The in vitro tissue anchoring ability was measured by two tissue /suture pullout tests,one for skin and the other for tendon tissue. Regardless of the type of tissue,the PP barbed suture with its higher modulus had a superior anchoring ability. Given the same suture material,improved anchoring performance was shown in tendon tissue.

关键词： barbed surgical sutures nylon polypropylene(PP) barb configuration skin and tendon

Case study approach to modeling historical disinfection by-product exposure in Iowa drinking waters

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Journal of Environmental Sciences 2017年第8期29卷 183-190页

作者： Stuart w.Krasner Kenneth P.Cantor peter J.weyer Mariana Hildesheim Gary Amy Metropolitan water District of Southern California Water Quality La Verne CA 91750 USA National Cancer Institute National Institutes of Health Bethesda MD 20892 USA Center for Health Effects of Environmental Contamination(CHEEC) University of Iowa Coralville IA 52242 USA Medical Research Solutions LLC Montgomery Village MD 20886 USA College of Engineering Computing and Applied SciencesClemson University Clemson SC 29631 USA

In the 1980 s, a case–control epidemiologic study was conducted in Iowa（USA） to analyze the association between exposure to disinfection by-products（DBPs） and bladder cancer risk. Trihalomethanes（THMs）, the most commonly measured and dominant class of DBPs in drinking water, served as a primary metric and surrogate for the full DBP *** THM exposure was calculated, based on rough estimates of past levels in Iowa. To reduce misclassification, a follow-up study was undertaken to improve estimates of past THM levels and to re-evaluate their association with cancer risk. In addition, the risk associated with haloacetic acids, another class of DBPs, was examined. In the original analysis, surface water treatment plants were assigned one of two possible THM levels depending on the point of chlorination. The re-assessment considered each utility treating surface or groundwater on a case-by-case basis. Multiple treatment/disinfection scenarios and water quality parameters were considered with actual DBP measurements to develop estimates of past levels. The highest annual average THM level in the re-analysis was156 μg/L compared to 74 μg/L for the original analysis. This allowed the analysis of subjects exposed at higher levels（〉 96 μg/L）. The re-analysis established a new approach, based on case studies and an understanding of the water quality and operational parameters that impact DBP formation, for determining historical exposure.

关键词： Disinfection by-products Trihalomethanes Haloacetic acids Exposure assessment Epidemiology Bladder cancer

Evaluation of thermal comfort and air quality of low-income housing in Kampala City,Uganda

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Energy and Built Environment 2022年第4期3卷 508-524页

作者： Derrick Kajjoba Hillary Kasedde peter w.Olupot Joseph D.Lwanyaga Department of Mechanical Engineering College of EngineeringDesignArt and TechnologyMakerere UniversityP.O Box 7062KampalaUganda Department of Mining and water Resources Engineering Faculty of EngineeringBusitema UniversityP.O.Box236TororoUganda

This paper presents the results of thermal comfort and air quality studies in naturally ventilated residential buildings in Kampala City,*** surveys were used for obtaining occupant subjective thermal sensation *** and outdoor measurements for air temperature(T_(a)),Mean Radiant Temperature(MRT),relative humidity,air speed,and air quality were done for seven buildings over fifteen days during the month of June *** software was used to develop the reference building model and to simulate strategies for improvement of thermal *** results showed that 67.8%of the respondents were comfortable with the indoor thermal *** indoor air temperature range was 22.7℃-27.9℃ which lies within the 80%acceptable limits set by ASHRAE *** measured indoor MRT range was 24.24℃-25.57℃.Measured levels of indoor PM_(2.5)were double the world Health Organization recommended limits,while the levels of PM 10 were thrice the recommended limits of ASHRAE *** CO_(2)concentrations were within the limits set by ASHRAE *** developed model predicted comfortable indoor conditions with a temperature range of 23.6℃-25.3℃ based on the 80%acceptable limits set by ASHRAE *** results show that majority of occupants preferred cooler temperatures during the day which is justified by the use of adaptive measures to obtain thermal comfort.

关键词： Thermal comfort Air quality Natural ventilation Low-income housing Uganda

Statin, testosterone and phosphodiesterase 5-inhibitor treatments and age related mortality in diabetes

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world Journal of Diabetes 2017年第3期8卷 104-111页

作者： Geoffrey Hackett peter w Jones Richard C Strange Sudarshan Ramachandran Department of Urology University of Bed-fordshire Department of Urology Heart of England NHS Foundation Trust Metabolic Research Group Institute of Science and Technology in Medicine Keele University Department of Clinical Biochemistry Heart of England NHS Foundation Trust Department of Clinical Biochemistry University Hospitals of North Midlands/Faculty of Health Sciences Staffordshire University

AIMTo determine how statins, testosterone (T) replacement therapy (TRT) and phosphodiesterase 5-inhibitors (PDE5I) influence age related mortality in diabetic *** studied 857 diabetic men screened for the BLAST study, stratifying them (mean follow-up = 3.8 years) into: (1) Normal T levels/untreated (total T > 12 nmol/L and free T > 0.25 nmol/L), Low T/untreated and Low T/treated; (2) PDE5I/untreated and PDE5I/treated; and (3) statin/untreated and statin/treated groups. The relationship between age and mortality, alone and with T/TRT, statin and PDE5I treatment was studied using logistic regression. Mortality probability and 95%CI were calculated from the above models for each *** was associated with mortality (logistic regression, OR = 1.10, 95%CI: 1.08-1.13, P with all factors included, age (OR = 1.08, 95%CI: 1.06-1.11, P w T/treated (OR = 0.38, 95%CI: 0.15-0.92, P = 0.033), PDE5I/treated (OR = 0.17, 95%CI: 0.053-0.56, P = 0.004) and statin/treated (OR = 0.59, 95%CI: 0.36-0.97, P = 0.038) were associated with lower mortality. Age related mortality was as described by Gompertz, r2 = 0.881 when Ln (mortality) was plotted against age. The probability of mortality and 95%CI (from logistic regression) of individuals, treated/untreated with the drugs, alone and in combination was plotted against age. Overlap of 95%CI lines was evident with statins and TRT. No overlap was evident with PDE5I alone and with statins and TRT, this suggesting a change in the relationship between age and *** show that statins, PDE5I and TRT reduce mortality in diabetes. PDE5I, alone and with the other treatments significantly alter age related mortality in diabetic men.

关键词： Type 2 diabetes Mortality Gompertz-Makeham equation Phosphodiesterase 5 inhibitors Male hypogonadism Statins Testosterone replacement therapy

Reversible Insertion of CO_(2)into a Bis(formazanate)Magnesium Complex

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CCS Chemistry 2023年第6期5卷 1277-1284页

作者： Da Jin Xiaofei Sun Alexander Hinz peter w.Roesky Institute for Inorganic Chemistry Karlsruhe Institute of Technology76131 Karlsruhe

The capture,storage,and release of CO_(2)is one of the most pressing issues in ***,we designed bis(formazanate)magnesium complexes as precursors,which were synthesized by straightforward transamination between the neutral formazan[PhNNC(4-tBuPh)NNHPh](LH)and[Mg{N(SiMe_(3))_(2)}_(2)].Depending on the solvent,either the homoleptic complex[L_(2)Mg]or the thf-coordinated complex[L_(2)Mg(thf)]was *** of the solvent-free complex[L_(2)Mg]with CO_(2)led to stoichiometric insertion into one of the four Mg–Nbonds with concomitant rearrangement of the ligand scaffold which adopts a trinuclear cagelike *** insertion reaction is reversible depending on thermolysis or treatment with tetrahydrofuran,which is corroborated by density functional theory *** showcases the first example of reversible uptake of CO_(2)by an s-block coordination compound.

关键词： reversibility CO_(2)activation formazanate magnesium s-block chemistry

Forging a Cage into a Chain:Stepwise Transformation of P_(4) by Silylenes to a Si_(3)P_(4) Motif

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CCS Chemistry 2022年第6期4卷 1843-1849页

作者： Xiaofei Sun Alexander Hinz peter w.Roesky Institute of Inorganic Chemistry Karlsruhe Institute of Technology(KIT)76131 Karlsruhe

we have discovered a route to access the longest low-valent molecular silaphospha-chain,a sevenmembered chain structure that incorporates three silicon and four phosphorus atoms by stepwise activation of white phosphorus(P_(4))using two different silylene *** chain species was formed via a highly reactive polyphosphide *** isolation of a stable analogue of this reaction intermediate was achieved by stepwise reaction with mono and bis(silylenes).Due to the rigidity of the ferrocenediyl framework of the bis(silylene),the isomerization process of the chain structure was *** studies such as natural bond orbital and atoms in molecules analyses of the seven-membered chain species indicated some degree of delocalization of the double bond system.

关键词： phosphorus P_(4)activation silylene silicon main group synthesis