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71.
72.
Ting Gong Iurie Curosu Frank Liebold Duy M. P. Vo Konrad Zierold Hans-Gerd Maas Chokri Cherif Viktor Mechtcherine 《Materials》2020,13(24)
The paper at hand presents an investigation of the tensile behavior of high-strength, strain-hardening cement-based composites (HS-SHCC), reinforced with a single layer of continuous, two-dimensional textile made of ultra-high molecular weight polyethylene (UHMWPE). Uniaxial tension tests were performed on the bare UHMWPE textiles, on plain HS-SHCC, and on the hybrid fiber-reinforced composites. The bond properties between the textile yarns and the surrounding composite were investigated in single-yarn pullout experiments. In order to assess the influence of bond strength between the yarn and HS-SHCC on the tensile behavior of the composites with hybrid fiber reinforcement, the textile samples were analyzed both with, and without, an additional coating of epoxy resin and sand. Compared to the composites reinforced with carbon yarns in previous studies by the authors, the high elongation capacity of the UHMWPE textile established the higher strain capacity of the hybrid fiber-reinforced composites, and showed superior energy absorption capacity up to failure. The UHMWPE textile limited the average crack width in comparison with that of plain HS-SHCC, but led to slightly larger crack widths when compared to equivalent composites reinforced with carbon textile, the reason for which was traced back to the lower Young’s modulus and the higher elongation capacity of the polymer textile. 相似文献
73.
Mireille Claustres Viktor Ko?ich Els Dequeker Brain Fowler Jayne Y Hehir-Kwa Konstantin Miller Cor Oosterwijk Borut Peterlin Conny van Ravenswaaij-Arts Uwe Zimmermann Orsetta Zuffardi Ros J Hastings David E Barton 《European journal of human genetics : EJHG》2014,22(2):160-170
Genetic test results can have considerable importance for patients, their parents and more remote family members. Clinical therapy and surveillance, reproductive decisions and genetic diagnostics in family members, including prenatal diagnosis, are based on these results. The genetic test report should therefore provide a clear, concise, accurate, fully interpretative and authoritative answer to the clinical question. The need for harmonizing reporting practice of genetic tests has been recognised by the External Quality Assessment (EQA), providers and laboratories. The ESHG Genetic Services Quality Committee has produced reporting guidelines for the genetic disciplines (biochemical, cytogenetic and molecular genetic). These guidelines give assistance on report content, including the interpretation of results. Selected examples of genetic test reports for all three disciplines are provided in an annexe.Diagnostic genetic testing is an extremely rapidly expanding area encompassing a broad range of laboratory investigations to analyse chromosomes (from classical karyotype to molecular cytogenetics), nucleic acids (DNA, RNA), proteins and metabolites used to detect heritable or somatic mutations, genotypes or phenotypes related to disease and health. Genetic testing requires particular consideration in that it is usually performed only once in a patient''s lifetime, and the results may have considerable importance for lifetime decisions not only for the individuals being tested but also for children and family. Interpreting and reporting variation in germline chromosomes, DNA sequences or their products is a heavy clinical responsibility for prediction of susceptibility to disease, patient diagnosis, prognosis, counselling, treatment or family planning. Providing a set of reporting frameworks that can be customised for different testing contexts but share some common principles could be beneficial to the practice of a number of laboratories, including non-OECD members and/or laboratories that do not participate in External Quality Assessments (EQA), and to laboratories with blurred boundaries between research and genetic testing services.Although several guidelines already exist for reporting the results of genetic testing,1,2,3 these focus on molecular genetic testing and do not cover the other two branches of laboratory genetics, namely biochemical genetics and cytogenetics. Based on recent surveys of EQA results presented by some European EQA providers and the request from genetic laboratories for comprehensive reporting guidelines, it was considered that a unifying attempt to harmonise the reporting practice of genetic tests in Europe and neighbouring countries would be welcome. 相似文献
74.
Cunjiang Yu Yuhang Li Xun Zhang Xian Huang Viktor Malyarchuk Shuodao Wang Yan Shi Li Gao Yewang Su Yihui Zhang Hangxun Xu Roger T. Hanlon Yonggang Huang John A. Rogers 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(36):12998-13003
Octopus, squid, cuttlefish, and other cephalopods exhibit exceptional capabilities for visually adapting to or differentiating from the coloration and texture of their surroundings, for the purpose of concealment, communication, predation, and reproduction. Long-standing interest in and emerging understanding of the underlying ultrastructure, physiological control, and photonic interactions has recently led to efforts in the construction of artificial systems that have key attributes found in the skins of these organisms. Despite several promising options in active materials for mimicking biological color tuning, existing routes to integrated systems do not include critical capabilities in distributed sensing and actuation. Research described here represents progress in this direction, demonstrated through the construction, experimental study, and computational modeling of materials, device elements, and integration schemes for cephalopod-inspired flexible sheets that can autonomously sense and adapt to the coloration of their surroundings. These systems combine high-performance, multiplexed arrays of actuators and photodetectors in laminated, multilayer configurations on flexible substrates, with overlaid arrangements of pixelated, color-changing elements. The concepts provide realistic routes to thin sheets that can be conformally wrapped onto solid objects to modulate their visual appearance, with potential relevance to consumer, industrial, and military applications.Recently established understanding of many of the key organ and cellular level mechanisms of cephalopod metachrosis (1–5) creates opportunities for the development of engineered systems that adopt similar principles. Here, critical capabilities in distributed sensing and actuation (6–9) must be coupled with elements that provide tunable coloration, such as the thermochromic systems reported here or alternatives such as cholesteric liquid crystals (10–13), electrokinetic and electrofluidic structures (14, 15), or colloidal crystals (16–19). Although interactive displays that incorporate distributed sensors for advanced touch interfaces (20–22) might have some relevance, such capabilities have not been explored in flexible systems or in designs that enable adaptive camouflage. The results reported here show that advances in heterogeneous integration and high-performance flexible/stretchable electronics provide a solution to these critical subsystems when exploited in thin multilayer, multifunctional assemblies. The findings encompass a complete set of materials, components, and integration schemes that enable adaptive optoelectronic camouflage sheets with designs that capture key features and functional capabilities of the skins of cephalopods. These systems combine semiconductor actuators, switching components, and light sensors with inorganic reflectors and organic color-changing materials in a way that allows autonomous matching to background coloration, through the well-known, separate working principles of each component. The multilayer configuration and the lamination processes used for assembly, along with the photopatternable thermochromic materials, are key to realization of these systems. Demonstration devices capable of producing black-and-white patterns that spontaneously match those of the surroundings, without user input or external measurement, involve multilayer architectures and ultrathin sheets of monocrystalline silicon in arrays of components for controlled, local Joule heating, photodetection, and two levels of matrix addressing, combined with metallic diffuse reflectors and simple thermochromic materials, all on soft, flexible substrates. Systematic experimental, computational, and analytical studies of the optical, electrical, thermal, and mechanical properties reveal the fundamental aspects of operation, and also provide quantitative design guidelines that are applicable to future embodiments.The skin of a cephalopod enables rapid, patterned physiological color change, or metachrosis, in a thin three-layered system (2, 23–25). The topmost layer is pigmentary coloration: chromatophore organs that retract or expand rapidly by direct control of muscles that are in turn controlled by nerves originating in the brain. This physiological on/off speed change ranges from ca. 250 to 750 ms. The middle and bottom layers are composed of structural coloration components. The middle layer comprises iridophore cells that can reflect all colors depending on angle of view; some are passive cells and others are physiologically controlled by a slower system: They can be turned on/off in 2–20 s (depending on species, or different cell types on different parts of the body). The bottom layer comprises leucophores (i.e., “white cells”) that are entirely passive (i.e., no physiological control; they are always “on”). This layer diffuses white in all directions (25) and can act as a bright backdrop against which expanded pigmentary chromatophores are viewed; this provides one way in which contrast of the pattern can be controlled (i.e., darkly pigmented chromatophores next to bright white reflective elements).The central control of skin patterning resides in the eyes, which, together with the central and peripheral nervous system, sense the visual background and route control signals throughout the skin to produce a coordinated pattern for communication or camouflage. In addition, the skin contains molecules known as opsins, which are known to be photosensitive in the retina and are thought to be photosensitive in the skin as well. They are hypothesized to play a role in distributed light sensing and control in the periphery (26), thus potentially adding a noncentralized component for skin patterning that enables sensing and actuation independent of the brain.One of the most important features of cephalopod skin—one that provides maximum optical diversity of appearances—is the coordinated action of (i) chromatophores, (ii) iridophores, (iii) leucophores, (iv) muscles, (v) central ocular organs, and (vi) distributed opsins (2, 23–25). The work described here demonstrates pixelated devices that include analogs to each of these key elements, except for the second and fifth, which can be easily incorporated with known photonic materials and conventional digital imagers. 相似文献
75.
Podhorec P Socha M Sokolowska-Mikolajczyk M Policar T Svinger VW Drozd B Kouril J 《General and comparative endocrinology》2012,175(1):34-38
Tench (Tinca tinca) is apparently the only known member of the Cyprinidae in which ovulation is stimulated following administration of a low dose of GnRH analogue (GnRHa) without a dopamine inhibitor. This study evaluated LH release effectiveness of the most commonly used GnRHa and clarified whether LH secretion followed by ovulation is subject to inhibitory dopaminergic control in tench. Fish were intraperitoneally injected with three types of GnRHa, GnRHa with dopamine inhibitor metoclopramide (combined treatment), or the dopamine inhibitor metoclopramide alone. LH concentrations at five sampling times (0, 6, 12, 24, and 33 h) together with ovulation success and fecundity index were recorded. The combined treatment triggered an almost immediate LH release peak with a gradual decline, and resulted in a high ovulation rate. In contrast to the combined treatment, an application of GnRHa alone at 10 μg kg(-1) induced gradual increase of LH concentrations with peaks close to ovulation time, and with high ovulation success. Significant differences in LH concentrations at 6 and 12h and no differences in ovulation success were found between the combined and the GnRHa alone treatments. Metoclopramide alone induced a small increase in LH with no ovulation. The study presents clear evidence of dopaminergic control of LH release in tench, with a high ovulation rate obtained after application of GnRHa alone or in combination with dopamine inhibitor. 相似文献
76.
Protein misfolding has been proposed to be a common pathogenic mechanism in many inborn errors of metabolism including cystathionine
β-synthase (CBS) deficiency. In this work, we describe the structural properties of nine CBS mutants that represent a common
molecular pathology in the CBS gene. Using thermolysin in two proteolytic techniques, we examined conformation of these mutants directly in crude cell extracts
after expression in E. coli. Proteolysis with thermolysin under native conditions appeared to be a useful technique even for very unstable mutant proteins,
whereas pulse proteolysis in a urea gradient had limited values for the study of the majority of CBS mutants due to their
instability. Mutants in the active core had either slightly increased unfolding (p.A114V, p.E302K and p.G307S) or extensive
unfolding with decreased stability (p.H65R, p.T191M, p.I278T and p.R369C). The extent of the unfolding inversely correlated
with the previously determined degree of tetrameric assembly and with the catalytic activity. In contrast, mutants bearing
aminoacid substitutions in the C-terminal regulatory domain (p.R439Q and p.D444N) had increased global stability with decreased
flexibility. This study shows that proteolytic techniques can reveal conformational abnormalities even for CBS mutants that
have activity and/or a degree of assembly similar to the wild-type enzyme. We present here a methodological strategy that
may be used in cell lysates to evaluate properties of proteins that tend to misfold and aggregate and that may be important
for conformational studies of disease-causing mutations in the field of inborn errors of metabolism. 相似文献
77.
78.
Taenia taeniaeformis is a globally distributed cestode, which uses felids as definitive and rodents as intermediate hosts. The complete mitochondrial DNA (mtDNA) of T. taeniaeformis from Germany (Tt-GER) was sequenced, and compared with that of another isolate from China (GenBank NC_014768; Tt-CHN), both taken from cats. Analysis of the two mtDNAs indicated that the isolates are significantly different from one another with 12.6% and 9.9% nucleotide and amino acid divergence between them, for concatenated protein-coding genes; overall difference based on a pairwise nucleotide alignment of complete mtDNAs was 11.8%. A phylogenetic analysis based on the 12 protein-coding genes of all available taeniid mtDNAs confirmed the two T. taeniaeformis isolates as sister taxa (likely separate species) and early divergent members of the genus, as suggested previously by morphology. Phylogenetic analysis of published fragments of mt genes rrnS, cox1 and nad1, which represent multiple geographic isolates of T. taeniaeformis also resolve two distinct clades that at present do not seem to be geographically isolated. Mean pairwise (nucleotide) differences between the two clades of T. taeniaeformis were approximately 11%, 10% and 13% in partial rrnS (182bp), cox1 (371bp) and nad1 (459bp) genes, respectively. Differences between entire mtDNAs and partial mt genes of the two T. taeniaeformis isolates are of a similar magnitude between established taeniid sister species. Tt-CHN differs from all other Taenia mtDNAs in lacking a short (~69bp) non-coding region between trnY and trnL1. Partial mt fragment analysis highlighted likely misidentifications of T. taeniaeformis on GenBank. 相似文献
79.
80.
Massari D Prpic-Massari L Kehler T Kastelan M Curkovic B Persic V Ruzic A Laskarin G 《Rheumatology international》2012,32(9):2777-2784
The objective of the present study was to investigate possible changes in granulysin (GNLY)-mediated cytotoxicity of peripheral blood lymphocytes in psoriatic arthritis (PsA) patients with respect to different phases of the disease. We prospectively enrolled 25 PsA patients in the active phase, 26 PsA patients in remission and 24 healthy controls. The simultaneous detection of intracellular GNLY and cell surface antigens (CD3 and CD56) was performed with flow cytometry. GNLY apoptotic protein was visualised by immunocytochemistry. Natural killer (NK) cell cytotoxicity was analysed with a cytotoxicity assay against human erythroleukaemia K-562 cells. The percentage of GNLY(+) cells did not differ significantly between PsA patients in the acute phase and those in remission; however, it was always higher than in healthy examinees due to the increased percentage of GNLY(+) cells within T cells, NKT cells, and both, and in the CD56(+dim) and CD56(+bright) NK subsets. The mean fluorescence intensity for GNLY was higher in all lymphocyte subpopulations in the acute phase than in remission and in healthy controls. Accordingly, GNLY-mediated NK cell cytotoxicity against K-562 cells of active phase PsA patients was significantly higher than that in patients in remission or in healthy controls. These findings demonstrated the involvement of GNLY in the worsening of PsA and suggested that GNLY mediated the development of joint lesions. 相似文献