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A novel near-infrared light responsive 4D printed nanoarchitecture with dynamically and remotely controllable transformation

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Nano Research 2019年第6期12卷 1381-1388页

作者： Haitao Cui Shida Miao timothy Esworthy Se-jun lee Xuan Zhou Sung Yun Hann thomas j.Webster Brent t.Harris Lijie Grace Zhang Department of Mechanical and Aerospace Engineering The George Washington UniversityWashingtonDC 20052USA Department of Chemical Engineering Northeastern UniversityBostonMA 02115USA Department of Neurology and Pathology Georgetown UniversityWashingtonDC 20007USA Departments of Electrical and Computer Engineering The George Washington UniversityWashingtonDC 20052USA Department of Biomedical Engineering The George Washington UniversityWashingtonDC 20052USA Department of Medicine The George Washington UniversityWashingtonDC 20052USA

Four-dimensional (4D) printing is an emerging and highly innovative additive manufacturing process by which to fabricate pre-designed,self-assembly structures with the ability to transform over ***,one of the critical challenges of 4D printing is the lack of advanced 4D printing systems that not only meet all the essential requirements of shape change but also possess smart,dynamic capabilities to spatiotemporally and instantly control the shape-transformation ***,we present a facile 4D printing platform which incorporates nanomaterials into the conventional stimuli-responsive polymer,allowing the 4D printed object to achieve a dynamic and remote controlled,on-time and position shape transformation.A proof-of-concept 4D printed brain model was created using near-infrared light (NIR) responsive nanocomposite to evaluate the capacity for controllable 4D transformation,and the feasibility of photothermal stimulation for modulating neural stem cell *** novel 4D printing strategy can not only be used to create dynamic 3D patterned biological structures that can spatiotemporally control their shapes or behaviors of transformation under a human benign stimulus (NIR),but can also provide a potential method for building complex self-morphing objects for widespread applications.

关键词： near-infrared light responsive four-dimensional (4D) printing dynamically and remotely controllable graphene brain neural stem cell

the LBD11-ROS feedback regulatory loop modulates vascular cambium proliferation and secondary growth in Arabidopsis

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Molecular Plant 2023年第7期16卷 1131-1145页

作者： tuong Vi t.Dang Seungchul lee Hyunwoo Cho Kyuha Choi IIdoo Hwang Department of Life Sciences POSTECH Biotech CenterPohang University of Science and TechnologyPohang 37673Korea Department of Industrial Plant Science&technology College of AgricultureLife&Environmental SciencesChungbuk National UniversityCheongju 28644Korea

Vascular cambium produces the phloem and xylem,vascular tissues that transport resources and provide mechanical support,making it an ideal target for crop ***,much remains unknown about how vascular cambium *** this study,through pharmaceutical and genetic manipulation of reactive oxygen species(ROS)maxima,we demonstrate a direct link between levels of ROS and activity of LAtERAL ORGAN BOUNDARIES DOMAIN 11(LBD11)in maintaining vascular cambium ***11 activates the transcriptionof several keyROS metabolic genes,including PEROXIDASE71and RESPIRAtORY BURSt OXIDASE HOMOLOGS D and F,to generate local ROS maxima in cambium,which in turn enhance the proliferation of cambial *** a negative feedback mechanism,higher Ros levels then repress LBD11 expression and maintain the balance of cambial cell *** findings thus reveal the role of a novel LBD11/ROS-dependent feedback regulatory system in maintaining vascular cambiumspecific redox homeostasis and radial growth inplants.

关键词： vascular cambium radial growth reactive oxygen species

Microstructure and brazing mechanism of porous Si_3N_4/Invar joint brazed with Ag-Cu-ti/Cu/Ag-Cu multi-layered filler

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journal of Materials Science & technology 2018年第4期34卷 713-719页

作者： j.Zhang j.Y.Liu t.P.Wang School of Materials Science and Engineering Harbin Institute of Technology

Porous Si3N4 was brazed to Invar alloy in this study, and Ag-Cu-ti/Cu/Ag-Cu multi-layered filler was designed to inhibit the formation of Fe2ti and Ni3ti intermetallic compounds. the effects of the brazing temperature and the thickness of Cu interlayer on the microstructure and mechanical properties of brazed joints were investigated. the typical microstructure of the joint brazed with multi-layered filler was porous Si3N4/tiN ＋ ti5Si3/Ag-Cu eutectic[Cu[Ag-Cu eutectic/Cu-rich layer ＋ diffusion layer/Invar. When the brazing temperature increased, the reaction layer at the ceramic/filler interface grew thicker and the Cu interlayer turned thinner. As the thickness of Cu interlayer increased from 50 to 150 μm, the joint strength first increased and then decreased. In this research, the maximum shear strength （73 MPa） was obtained when being brazed at 1173 K with a 100 μm Cu interlayer applied in the filler, which was 55% higher than that brazed with single Ag-Cu-ti brazing alloy and had reached 86% of the ceramic. the release of residual stress and the barrier effect of Cu interlayer to inhibit the formation of Fe2ti and Ni3ti intermetallics played the major role in the improvement of joint strength.

关键词： Porous Si3N4 Invar alloy Brazing Microstructure Mechanical properties

Changes in South Asian monsoon: New high-resolution paleoclimatic records from tibet, China

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Chinese Science Bulletin 2000年第1期45卷 87-91页

作者： j.t.Overpeck LIU Kambiu j.t.Overpeck Department of Geography and Anthropology Louisiana State UniversityBaton RougeLA 70803USANOAA Paleoclimatology ProgramNational Geophysical Data CenterBoulderCO 80303USANOAA Paleoclimatology Program National Geophysical Data Center Boulder CO 80303 USA

High-resolution pollen records from 6 small lakes in the tibetan Plateau provided the details of evolution of South Asian monsoon since the Last Glacial Maximum. Prior to 16 kaBP, the region was a desert-steppe characterized by cold and dry climates, the january temperature was 7 -10℃lower than that of present and the annual precipitation only accounted for 40% of the present. the temperature and precipitation increased gradually and trees began to live in the region after 12 kaBP, but during the interval from 9.2 to 6.3 kaBP, forest and forest-meadow appeared occasionally. From 8 to 5 kaBP, both january and july temperature was 2-3℃ higher and annual precipitation was also about 200 mm higher than that of the present. After 5 kaBP, temperature and precipitation decreased linearly and steppe vegetation began to degenerate.

关键词： South Asian monsoon pollen records paleovegetation and paleoclimate tibet.

On the polynomiality and asymptotics of moments of sizes for random(n,dn ± 1)-core partitions with distinct parts

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Science China Mathematics 2021年第4期64卷 869-886页

作者： Huan Xiong Wenston j.t.Zang Institut de Recherche Mathematique Avancee Universite de Strasbourg et CNRSStrasbourg 67000France Institute of Advanced Study of Mathematics Harbin Institute of TechnologyHarbin 150001China

Amdeberhan’s conjectures on the enumeration,the average size,and the largest size of(n,n+1)-core partitions with distinct parts have motivated many research on this ***,Straub(2016)and Nath and Sellers(2017)obtained formulas for the numbers of(n,dn-1)-and(n,dn+1)-core partitions with distinct parts,*** X_(s,t) be the size of a uniform random(s,t)-core partition with distinct parts when s and t are coprime to each *** explicit formulas for the k-th moments E[X_(n,n+1)^(k)]and E[X_(2 n+1,2 n+3)^(k)]were given by Zaleski and Zeilberger(2017)when k is ***(2017)also studied the expectation and higher moments of X_(n,dn-1) and conjectured some polynomiality properties concerning them in ar Xiv:*** by the above works,we derive several polynomiality results and asymptotic formulas for the k-th moments of X_(n,dn+1) and X_(n,dn-1) in this paper,by studying theβ-sets of core *** particular,we show that these k-th moments are asymptotically some polynomials of n with degrees at most 2 k,when d is given and n tends to ***,when d=1,we derive that the k-th moment E[X_(n,n+1)^(k)]of X_(n,n+1) is asymptotically equal to(n^(2)/10)^(k)when n tends to *** explicit formulas for the expectations E[X_(n,dn+1)]and E[X_(n,dn-1)]are also ***(n,dn-1)-core case in our results proves several conjectures of Zaleski(2017)on the polynomiality of the expectation and higher moments of X_(n,dn-1).

关键词： partition hook length core partition average size distinct part

Surface modification of stratum corneum for drug delivery and skin care by microplasma discharge treatment

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Plasma Science and technology 2019年第6期21卷 1-8页

作者： j KRIStOF t AOSHIMA M BLAjAN K SHIMIZU Graduate School of Science and technology Shizuoka University 432-8561 Hamamatsu Japan Department of Electrical and Electronic Engineering Shizuoka University 432-8561 Hamamatsu Japan Organization for Innovation and Social Collaboration Shizuoka University 432-8561 Hamamatsu Japan

Human skin is the largest organ and also the main barrier that prevents foreign substances from entering the *** surface properties of the skin are relevant for transdermal drug delivery and *** micropig skin is used as a substitute for human skin.A microplasma electrode is used for surface modification of the skin epidermal layer of the Yucatan *** dielectric barrier discharge has a thin dielectric as a barrier (~50 μm) and a frequency of 25 *** surface properties of the epidermal layer were characterized by the measurement of the contact angle of the water *** effects of different gases such as air,nitrogen,oxygen,helium or argon were *** change of the contact angle is temporal and it is returned to its initial state after several *** the gases used for plasma ignition,oxygen and argon were the most effective for skin *** distance of the skin from the electrode and the treatment time played a crucial roles in the increasing water contact *** of surface atomic concentration were determined by x-ray photoelectron *** microplasma treatment,the oxygen and nitrogen concentration increased at the skin surface.

关键词： microplasma contact angle skin stratum corneum XPS

Strong-form framework for solving boundary value problems with geometric nonlinearity

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Applied Mathematics and Mechanics(English Edition) 2016年第12期37卷 1707-1720页

作者： j.P.YANG W.t.SU Department of Civil Engineering Chiao Tung University

In this paper, we present a strong-form framework for solving the boundary value problems with geometric nonlinearity, in which an incremental theory is developed for the problem based on the Newton-Raphson scheme. Conventionally, the finite ele- ment methods （FEMs） or weak-form based meshfree methods have often been adopted to solve geometric nonlinear problems. However, issues, such as the mesh dependency, the numerical integration, and the boundary imposition, make these approaches com- putationally inefficient. Recently, strong-form collocation methods have been called on to solve the boundary value problems. the feasibility of the collocation method with the nodal discretization such as the radial basis collocation method （RBCM） motivates the present study. Due to the limited application to the nonlinear analysis in a strong form, we formulate the equation of equilibrium, along with the boundary conditions, in an incremental-iterative sense using the RBCM. the efficacy of the proposed framework is numerically demonstrated with the solution of two benchmark problems involving the geometric nonlinearity. Compared with the conventional weak-form formulation, the pro- posed framework is advantageous as no quadrature rule is needed in constructing the governing equation, and no mesh limitation exists with the deformed geometry in the increment al-it erative process.

关键词： geometric nonlinearity incremental-iterative algorithm radial basis collo-cation method (RBCM) strong form

Biological transformation,kinetics and dose-response assessments of bound musk ketone hemoglobin adducts in rainbow trout as biomarkers of environmental exposure

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journal of Environmental Sciences 2008年第7期20卷 878-884页

作者： M A Mottaleb j H Zimmerman t W Moy Department of Chemistry and Biochemistry Baylor UniversityP.O.Box 97348WacoTX 76798USA. U.S.Environmental Protection Agency National Exposure Research LaboratoryEnvironmental Sciences Division944 East Harmon AveLas VegasNV 89119USA

Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other ***,aquatic organisms can be continuously exposed to *** this study,kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite,bound to cysteine-hemoglobin (Hb) in rainbow trout,formed by enzymatic nitro-reduction of MK have been *** were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg MK/g ***...

关键词： biotransformation kinetics hemoglobin adducts dose-response nitro musks biomarker fish

Review:Resuspension of wall deposits in spray dryers

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1762-1774页

作者： HANUS M.j. LANGRISH t.A.G. School of Chemical and Biomolecular Engineering University of Sydney Sydney NSW 2006 Australia

Wall deposition occurs in spray dryers when dried or partially dried particles contact and adhere to the walls during operation, thus reducing the yield of product collected. Wall deposits also present a product contamination risk and a fire or explosion risk when spray drying products that oxidize exothermically, such as milk powder. Re-entrainment is the resuspension of spray dryer wall deposits into the main gas stream for collection as product. Literature suggests that the process for re-entrainment of particles from spray dryer wall deposits is strongly dependent on particle size and gas velocity.

关键词： Wall deposition Spray dryers Dried particles Re-entrainment Adhesive forces