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MatthiasZhr Dennis Friedrich Tania Y.Kloth Gerhard Goldmann Helmut Tributsch 《仿生工程学报(英文版)》2010,(3):284-293
In strong solar light, silicon solar panels can heat up by 70℃ and, thereby, loose approximately one third of their efficiencyfor electricity generation. Leaf structures of plants on the other hand, have developed a series of technological adaptations,which allow them to limit their temperature to 40-45℃ in full sunlight, even if water evaporation is suppressed. This is accomplishedby several strategies such as limitation of leaf size, optimization of aerodynamics in wind, limitation of absorbedsolar energy only to the useful fraction of radiation and by efficient thermal emission. Optical and infrared thermographicmeasurements under a solar simulator and in a streaming channel were used to investigate the corresponding properties of leavesand to identify suitable bionic model systems. Experiments started with the serrated structure of ordinary green leaves distributedover typical twig structures and finally identified the Australian palm tree Licuala ramsayi as a more useful bionic model. Itcombines a large area for solar energy harvesting with optimized aerodynamic properties for cooling and is able to restructureitself as a protection against strong winds. The bionic models, which were constructed and built, are analyzed and discussed. 相似文献
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Wolfgang H. Goldmann 《Cell biology international》2021,45(8):1624-1632
Metallic materials are commonly used for load-bearing implants and as internal fixation devices. It is customary to use austenitic stainless steel, especially surgical grade type 316L SS as temporary and Ti alloys as permanent implants. However, long-term, poor bonding with bone, corrosion, and release of metal ions, such as chromium and nickel occur. These ions are powerful allergens and carcinogens and their uncontrolled leaching may be avoided by surface coatings. Therefore, bioactive glasses (BGs) became a vital biomedical material, which can form a biologically active phase of hydroxycarbonate apatite on their surface when in contact with physiological fluids. To reduce the high coefficient of friction and the brittle nature of BGs, polymers are normally incorporated to avoid the high-temperature sintering/densification of ceramic-only coatings. For medical application, electrophoretic deposition (EPD) is now used for polymer (organic) and ceramic (inorganic) components at room temperature due to its simplicity, control of coating thickness and uniformity, low cost of equipment, ability to coat substrates of intricate shape and to supply thick films in composite form, high purity of deposits as well as no phase transformation during coating. Although extensive research has been conducted on polymer/inorganic composite coatings, only some studies have reported multifunctional properties, such as biological antibacterial activity, enhanced cell adhesion, controlled drug release ability, and mechanical properties. This review will focus on biodegradable coatings, including zien, chitosan, gelatin, cellulose loaded with antibacterial drugs/metallic ions/natural herbs on biostable substrates (PEEK/PMMA/PCL/PLLA layers), which have the potential of multifunctional coating for metallic implants. 相似文献
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Psychrophilic microorganisms and their cold-active enzymes 总被引:2,自引:0,他引:2
JE Brenchley 《Journal of industrial microbiology & biotechnology》1996,17(5-6):432-437
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David L Scott Gerold Diez Wolfgang H Goldmann 《Theoretical biology & medical modelling》2006,3(1):17-14
Background
Over the past decade our laboratory has focused on understanding how soluble cytoskeleton-associated proteins interact with membranes and other lipid aggregates. Many protein domains mediating specific cell membrane interactions appear by fluorescence microscopy and other precision techniques to be partially inserted into the lipid bilayer. It is unclear whether these protein-lipid-interactions are dependent on shared protein motifs or unique regional physiochemistry, or are due to more global characteristics of the protein. 相似文献258.
Cyclins are indispensable elements of the cell cycle and derangement of their function can lead to cancer formation. Recent studies have also revealed more mechanisms through which cyclins can express their oncogenic potential. This review focuses on the aberrant expression of G1/S cyclins and especially cyclin D and cyclin E; the pathways through which they lead to tumour formation and their involvement in different types of cancer. These elements indicate the mechanisms that could act as targets for cancer therapy. 相似文献
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The aim of this study was to identify the PRNP polymorphisms outside the standard codons 136, 154 and 171 in 1110 sheep with no clinical sign of scrapie from all 18 Turkish native sheep breeds and compare our results with published data on ovine PRNP polymorphism from other regions of the world. Among the 22 amino acid polymorphisms and three silent mutations, 10 were novel for ovine PRNP: p.Gly94Gly, p.Leu128Ile, p.Met132Leu, p.Ser135Arg, p.Met137Val, p.Asn146Lys, p.Arg159Arg, p.Tyr160Asn, p.Gln163His and p.Thr193Ser. These data reveal that sheep breeds close to the historic center of small ruminant domestication have remained highly diverse in the prion gene locus, with distinctive genetic similarities to both Asian and European sheep breeds. 相似文献