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Phylogenetic position of sponges in early metazoan evolution and bionic applications of siliceous sponge spicules

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chinese Science Bulletin 2007年第22期52卷 3029-3040页

作者： Werner e g MULLeR WANg XiaoHong ZeNg LingSen Heinz c ScHRODeR Institut for Physiologische chemie Abteilung Angewandte Molekularbiologie Universit&t Duesbergweg 6 D-55099 Mainz Germany National Research center for geoanalysis Beijing 100037 China Faculty for environmental Sciences Peking University Beijing 100871 China Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Sponges are the oldest and the simplest but not primitive multicellular animals. They represent the earliest evolutionary metazoan phylum still extant. It was a long and painful scientific process to posi-tion the most enigmatic and mysterious metazoan,the Porifera,into their correct phylogenetic place among the eukaryotes in general and multicellular animals in particular. As living fossils,sponges provide the best evidence for the early evolution of Metazoa. More recently,interest has been focused on the bionic applications of sponges' siliceous spicules,after the discovery of their unique structure and high fiber performance. In this review,the emergence of sponges,evolutionary novelties found in sponges,and the phylogenetic position of sponges in early metazoan evolution are highlighted. In ad-dition,the present state of knowledge on silicatein-mediated "biosilica" formation in marine sponges,including the involvement of other molecules in silica metabolism and their potential application in nanobiotechnology and medicine,is given.

关键词：海绵多细胞动物仿生学硅土

Flashing light in sponges through their siliceous fiber network:A new strategy of “neuronal transmission” in animals

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chinese Science Bulletin 2012年第25期57卷 3300-3311页

作者： WANg XiaoHong FAN XingTao ScHRODeR Heinz c MULLeR Werner e g National Research center for geoanalysis Chinese Academy of Geological SciencesBeijing 100037China eRc Advanced grant Research group at the Institute for Physiological chemistry University Medical Center of the Johannes GutenbergUniversityMainz D-55099Germany

Sponges(phylum Porifera) represent a successful animal taxon that evolved prior to the ediacaran-cambrian boundary(542 million years ago).They have developed an almost complete array of cell-and tissue-based interaction systems necessary for the establishment of a functional,multicellular ***,a network of neurons,one cell/tissue-communication system is missing in *** fact is puzzling and enigmatic,because these animals possess receptors known to be involved in the nervous system in evolutionary younger animal *** an example,the metabotropic glutamate/gABA-like receptor has been identified and cloned by ***,we have identified a novel light transmission/light responsive system in sponges that is based on their skeletal elements,the siliceous glass fibers,termed *** classes of sponges,the Hexactinellida and the Demospongiae,possess a siliceous skeleton that is composed of *** the large spicules from hexactinellid sponges(>5 cm) revealed that these spicules are effective light-collecting optical *** we can report that the demosponge,Suberites domuncula,has a biosensor system consisting of the(organic) light producing luciferase and the(inorganic) light transducing silica *** light transmission features of these smaller spicules(200 μm) has been demonstrated and the ability of the sponge tissue to generate light had been *** for a luciferase gene in *** was *** the next step,we searched for a protein potentially involved in light *** a protein was identified,cloned and recombinantly expressed from *** protein sequence displays two domains characteristic of a cryptochrome,the N-terminal photolyase-related region and the c-terminal FAD-binding *** experimental data indicate that sponges may employ a network of luciferase-like proteins,a spicular system and a cryptochrome as the light source,optical waveguide and photosensor,***

关键词：海绵组织动物类群光纤网络硅质神经传导闪烁荧光素酶基因蛋白质序列

enhancing perianal disease management with integrated physical and psychological approaches

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World Journal of clinical cases 2025年第2期13卷 59-63页

作者： Uchenna e Okpete Haewon Byeon Department of Digital Anti-aging Healthcare(BK21) Inje UniversityGimhae 50834South Korea

This article provides a comprehensive analysis of the study by Hou et al,focusing on the complex interplay between psychological and physical factors in the postoperative recovery(POR)of patients with perianal *** study sheds light on how illness perception,anxiety,and depression significantly influence recovery *** et al developed a predictive model that demonstrated high accuracy in identifying patients at risk of poor *** article explores the critical role of pre-operative psychological assessment,highlighting the need for mental health support and personalized recovery plans in enhancing POR quality.A multidisciplinary approach,integrating mental health professionals with surgeons,anesthesiologists,and other specialists,is emphasized to ensure comprehensive care for *** study’s findings serve as a call to integrate psychological care into surgical practice to optimize outcomes for patients with perianal diseases.

关键词： Perianal disease Post-operative recovery Anxiety Depression Pain management emotional well-being Multidisciplinary approach

estimating costs of salvage logging for large-scale burned forest lands: A case study on Turkey's Mediterranean coast

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Journal of Forestry Research 2021年第5期32卷 1899-1909页

作者： Neşe gülci Faculty of Forestry Kahramanmaras Sutcu Imam University46100 KahramanmarasTurkey

Different forest fires causing different degrees of effects occur in fire-sensitive forests due to various reasons such as climate *** as well as harmful aspects of forest fires are a multi-disciplinary research *** information systems(gIS)and remote sensing(RS)methods offer a number of benefits for researchers and operators in the field of forest fire *** present study analyses timber pricing based on forest contractor demands of post-salvage logging *** effect of timber obtained from compartment units on producers’pricing policy was *** forest fire area(2500 ha)located in Antalya in Turkey was selected as the main study *** parameters(aspect,slope and slope position),stand types(diameter class and crown closure),and burn severity were analyzed together using gIS and R software packages.A multi-linear regression model(R^(2)=0.752)demonstrated that factors that had the most impact on pricing were slope position,aspect,stand age,crown closure and burn *** model can be used to estimate salvage logging prices in calabrian pine(Pinus brutia Ten.)stands with similar *** administrators and contractors may readily address the unit price of timber by estimating approximate costs in a given forest area for which they are going to *** will help reduce operational planning times of harvesting procedures in burned stands.

关键词： Timber extraction Forest fires Stumpage sale cost estimation Sustainability crown fire

Three-dimensional biomagnetic Maxwell fluid flow over a stretching surface in presence of heat source/sink

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International Journal of Biomathematics 2019年第3期12卷 207-226页

作者： M.g.Murtaza M.Ferdows J.c.Misra e.e.Tzirtzilakis Research group of Fluid Flow Modeling and Simulation Department of Applied Mathematics University of Dhaka Dhaka-1000 Bangladesh centre for Theoretical Studies Indian Institute of Technology Kharagpur Kharagpur 721302 India Fluid Dynamics & Turbomachinery Laboratory Department of Mechanical engineering Technological educational Institute of Western greece 1 M. Aleksandrou Str Koukouli 26334 Patras Greece

The present paper deals with the study of three-dimensional boundary layer flow of biomagnetic Maxwell fluid over a plane horizontal surface stretched linearly along two mutually perpendicular directions. Basic principles of magnetohydrodynamics (MHD) and ferro-hydrodynamics (FHD) have been employed. The effect of heat generation/absorption has been taken into consideration. The study is theoretical and is conducted by using a combination of approximate and numerical techniques. By using the method of similarity transformation, the governing nonlinear partial differential equations are converted into a set of coupled ordinary differential equations. In the sequel, a suitable numerical method has been developed to solve the coupled differential equations. The accuracy of the numerical method has been checked by comparing the numerical results with those of an earlier study reported in available literatures. effects of various parameters involved in the study, viz. the magnetohydrodynamic and ferromagnetic parameters, Deborah number, stretching ratio and heat generation on the fluid flow profiles are investigated and the results have been presented graphically. Variations of the skin friction, heat transfer rate and relative wall pressure with change in hydrodynamic and ferromagnetic parameters have also been illustrated. It is found that due to the influence of the Kelvin force, the velocity component in xx-direction is greater than the corresponding one in the hydrodynamic case, but the opposite is true for the velocity component in the yy-direction. We also found that the temperature of the fluid for hydrodynamic flow is greater than that for MHD or FHD flow. It is even greater for BFD flows. The numerical results of the study reveal that the characteristics of blood flow are significantly affected by the presence of a magnetic field.

关键词： Biomagnetic fluid magnetic dipole magnetization heat transfer stretching surface

AN AccURATe NUMeRIcAL SOLUTION OF A TWO DIMeNSIONAL HeAT TRANSFeR PROBLeM WITH A PARABOLIc BOUNDARY LAYeR

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Journal of computational Mathematics 1998年第1期16卷 27-39页

作者： c.clavero J.J.H.Miller e.O'Riordan g.I.Shishkin Universidad de Zaragoza 西班牙 Trinity college 爱尔兰 Dublin city University 爱尔兰 Institute of Mathematics and Mechanics 俄罗斯

A singularly perturbed linear convection-diffusion problem for heat transfer in two dimensions with a parabolic boundary layer is solved numerically The numerical method consists of a special piecewise uniform mesh condensing in a neighbourhood of the parabolic layer and a standard finite difference operator satisfying a discrete maximum principle. The numerical computations demonstrate numerically that the method is epsilon-uniform in the sense that the Fate of convergence and error constant of the method are independent of the singular perturbation parameter epsilon. This means that no matter how small the singular perturbation parameter epsilon is, the numerical method produces solutions with guaranteed accuracy depending solely on the number of mesh points used.

关键词： linear convection-diffusion parabolic layer piecewise uniform mesh finite difference

In situ selective laser gas nitriding for composite TiN/Ti-6Al-4V fabrication via laser powder bed fusion

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Journal of Materials Science & Technology 2020年第10期42卷 98-107页

作者： P.A.Morton H.c.Taylor L.e.Murr O.g.Delgado c.A.Terrazas R.B.Wicker W.M.Keck center for 3D Innovation The University of Texas at El PasoEl PasoTX79968USA Department of Mechanical engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

Laser-assisted gas nitriding of selective Ti-6Al-4V surfaces has been achieved during laser powder bed fusion fabrication by exchanging the argon build gas environment with *** variation of processing parameters allowed microdendritic Ti N surface coatings to be formed having thicknesses ranging from a few tens of microns to several hundred microns,with TiN dendrite microstructure volume fractions ranging from 0.6 to 0.75;and corresponding Vickers microindentation hardness values ranging from^7.5 gPa–9.5 *** TiN hard layers ranging from 50μm to 150μm thick were also fabricated in the laser-beam additively manufactured Ti-6Al-4V alloy producing prototype,hybrid,planar composites having alternating,ductile Ti-6Al-4V layers with a hardness of^4.5 gPa and a stiff,TiN layer with a hardness of^8.5 *** results demonstrate prospects for fabricating novel,additively manufactured components having selective,hard,wear and corrosion resistant coatings along with periodic,planar or complex metal matrix composite regimes exhibiting superior toughness and related mechanical properties.

关键词： Ti-6Al-4V TiN ceramic coatings and embedded layers Dendritic microstructures Selective laser melting Additive manufacturing Metal matrix composites Selective nitriding

An efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng e Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China college of Bioresources chemical and Materials engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China college of chemical and Molecular engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Sintering and mechanical properties of β-Sic powder obtained from waste tires

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Journal of Advanced ceramics 2016年第1期5卷 40-46页

作者： g.MAgNANI S.gALVAgNO g.SIcO S.PORTOFINO c.FReDA e.BURReSI eNeA SSPT-PROMAS-TEMAF Faenza Research Laboratories Via Ravegnana 186 48018 Faenza(RA) Italy eNeA SSPT-PROMAS-NANO Portici Research Center P.le Enrico Fermi 1 80055 Portici(NA) Italy eNeA SSPT-PROMAS-MATAS Brindisi Research Center S.S.7 Appia km 70600 72100 Brindisi Italy

Plasma synthesized Sic powder obtained from quartz and carbonaceous residue of waste tires was successfully sintered at 1925 ℃ by pressureless liquid-phase method using yttria and alumina as sintering aids (T-Sic). comparison with sintered Sic obtained from commercial powder (c-Sic) put in evidence of similar sintered density (98%T.D.), but much finer microstructure of T-Sic than that of c-Sic. T-Sic also showed higher flexural strength than c-Sic both at room temperature (508 vs. 458 MPa) and at 1500 ℃ (280 vs. 171 MPa). Difference in liquid phase was responsible for the differences in hardness and fracture toughness. The high value of the Young’s modulus of T-Sic (427 MPa) confirmed the high degree of sinterability of this powder and that it can be a promising candidate for structural applications with high added value.

关键词： sintering mechanical properties Sic structural application