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181.
Pisal Rishikaysh Kapil Dev Daniel Diaz Wasay Mohiuddin Shaikh Qureshi Stanislav Filip Jaroslav Mokry 《International journal of molecular sciences》2014,15(1):1647-1670
Hair follicle morphogenesis depends on Wnt, Shh, Notch, BMP and other signaling pathways interplay between epithelial and mesenchymal cells. The Wnt pathway plays an essential role during hair follicle induction, Shh is involved in morphogenesis and late stage differentiation, Notch signaling determines stem cell fate while BMP is involved in cellular differentiation. The Wnt pathway is considered to be the master regulator during hair follicle morphogenesis. Wnt signaling proceeds through EDA/EDAR/NF-κB signaling. NF-κB regulates the Wnt pathway and acts as a signal mediator by upregulating the expression of Shh ligand. Signal crosstalk between epithelial and mesenchymal cells takes place mainly through primary cilia. Primary cilia formation is initiated with epithelial laminin-511 interaction with dermal β-1 integrin, which also upregulates expression of downstream effectors of Shh pathway in dermal lineage. PDGF signal transduction essential for crosstalk is mediated through epithelial PDGF-A and PDGFRα expressed on the primary cilia. Dermal Shh and PDGF signaling up-regulates dermal noggin expression; noggin is a potent inhibitor of BMP signaling which helps in counteracting BMP mediated β-catenin inhibition. This interplay of signaling between the epithelial and dermal lineage helps in epithelial Shh signal amplification. The dermal Wnt pathway helps in upregulation of epithelial Notch expression. Dysregulation of these pathways leads to certain abnormalities and in some cases even tumor outgrowth. 相似文献
182.
Anticorrosion efficiency of organic coatings depending on the pigment volume concentration of polyaniline phosphate 总被引:1,自引:0,他引:1
Polyaniline (PANI) was synthesized by reaction in an aqueous solution of ammonium peroxodisulfate and phosphoric acid. PANI was characterized by means of scanning electron microscopy and its physical–chemical properties were determined. Simultaneously with the synthesized PANI epoxy-ester coatings containing 3, 5, 10, 15, 20 and 24 vol.% of PANI as a corrosion inhibitor were formulated. The coatings were tested for their mechanical properties, film hardness and corrosion resistance. The testing of the anticorrosion efficiency of PANI as corrosion inhibitor was based on accelerated corrosion tests: in condensed water, NaCl mist, and condensing water and SO2. The prepared PANI displayed inhibition effects in corrosion reactions progressing on a steel base under the organic coating. The synthesized PANI provides good anticorrosion efficiency in an epoxy-ester coating. The studied system does not contain any heavy metals harmful to the environment. 相似文献
183.
Lszl Ivanizs Ilaria Marcotuli Marianna Rakszegi Balzs Kalapos Kitti Szke-Pzsi Andrs Farkas Edina Türksi Eszter Gal Klaudia Kruppa Pter Kovcs va Dark va Szakcs Mahmoud Said Petr Cpal Jaroslav Doleel Agata Gadaleta Istvn Molnr 《International journal of molecular sciences》2022,23(7)
Grain dietary fiber content is an important health-promoting trait of bread wheat. A dominant dietary fiber component of wheat is the cell wall polysaccharide arabinoxylan and the goatgrass Aegilops biuncialis has high β-glucan content, which makes it an attractive gene source to develop wheat lines with modified fiber composition. In order to support introgression breeding, this work examined genetic variability in grain β-glucan, pentosan, and protein content in a collection of Ae. biuncialis. A large variation in grain protein and edible fiber content was revealed, reflecting the origin of Ae. biuncialis accessions from different eco-geographical habitats. Association analysis using DArTseq-derived SNPs identified 34 QTLs associated with β-glucan, pentosan, water-extractable pentosan, and protein content. Mapping the markers to draft chromosome assemblies of diploid progenitors of Ae. biuncialis underlined the role of genes on chromosomes 1Mb, 4Mb, and 5Mb in the formation of grain β-glucan content, while other QTLs on chromosome groups 3, 6, and 1 identified genes responsible for total- and water-extractable pentosan content. Functional annotation of the associated marker sequences identified fourteen genes, nine of which were identified in other monocots. The QTLs and genes identified in the present work are attractive targets for chromosome-mediated gene transfer to improve the health-promoting properties of wheat-derived foods. 相似文献
184.
Jaroslav Maek 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1940,80(3):235-241
Ohne Zusammenfassung 相似文献
185.
Jaroslav ev
ík 《Electronic Notes in Theoretical Computer Science》2007,190(1):133
In this paper we use a program logic and automatic theorem provers to certify resource usage of low-level bytecode programs equipped with annotations describing resource consumption for methods. We have adapted an existing resource counting logic [Aspinall, D., L. Beringer, M. Hofmann, H.-W. Loidl and A. Momigliano, A program logic for resource verification, in: Proceedings of 17th International Conference on Theorem Proving in Higher Order Logics (TPHOLs2004), Lecture Notes in Computer Science 3223 (2004), pp. 34–49] to fit the first-order setting, implemented a verification condition generator, and tested our approach on programs that contain recursion and deal with recursive data structures. We have successfully applied our framework to programs that did not involve any updates to recursive data structures. But mutation is more tricky because of aliasing of heap. We discuss problems related to this and suggest techniques to solve them. 相似文献
186.
Boron oxide films were grown on silicon substrates by radio-frequency (rf) unbalanced magnetron sputtering of a boron target in argon-oxygen gas mixtures with different compositions. Microscopic analyses show that overall boron oxide films are amorphous. The film prepared at oxygen/argon flow rate ratio > 0.05 developed large crystallites of boric acid in localize areas of amorphous boron oxide matrices. These crystallites were unstable and at electron microscopic analysis they continuously transformed to a cubic HBO2 phase and then completely vanished leaving an underlying amorphous boron oxide film behind. The analyses indicate the coexistence of B6O, HBO2 crystallites and amorphous boron oxide matrices. Fourier transform infrared (FTIR) spectra revealed spectral bands of BOH, BO, BOB and BH groups. Nanohardness and elastic modulus of a film prepared at low oxygen concentration approach 30 and 300 GPa, respectively. These parameters however vary with deposition conditions. 相似文献
187.
Vladimír Koval Carlos Alemany Jaroslav Briančin Helena Bruncková 《Journal of Electroceramics》2003,10(1):19-29
The dielectric properties and phase transition behavior of the pseudo-ternary xPb(Mg1/3Nb2/3)O3-(1 – x)Pb(Zr,Ti)O3 solid solution system were investigated as a function of the Pb(Mg1/3Nb2/3)O3 (PMN) content and Ti/Zr ratio for selected compositions. The investigations have demonstrated a general trend in broadening of the phase transition and increasing diffusivity with increasing PMN content. For the morphotropic phase boundary (MPB) compositions, the dielectric permittivity maximum, its temperature (T
m) and the Curie-Weiss constant were found to decrease with increasing Mg1/3Nb2/3 concentration. When a Ti/Zr ratio was constant and equal to 53/47, temperature-dependent investigations demonstrated that the dielectric parameters involved in a modified Curie-Weiss law increase monotonically with increasing PMN content and T
m moves toward room temperature with average rate of –4.1°C/mol% as well. A phase transition in 0.5PMN-0.5Pb(Zr0.47Ti0.53)O3 and 0.25PMN-0.75Pb(Zr0.60Ti0.40)O3 ceramic systems exhibited a diffused behavior with a characteristic frequency dependence of T
m. From pyroelectric measurement, an unusual spontaneous polarization behavior at about 215 K is reported for some MPB compositions. 相似文献
188.
Radiance caching for efficient global illumination computation 总被引:1,自引:0,他引:1
Krivánek J Gautron P Pattanaik S Bouatouch K 《IEEE transactions on visualization and computer graphics》2005,11(5):550-561
In this paper, we present a ray tracing-based method for accelerated global illumination computation in scenes with low-frequency glossy BRDFs. The method is based on sparse sampling, caching, and interpolating radiance on glossy surfaces. In particular, we extend the irradiance caching scheme proposed by Ward et al. (1988) to cache and interpolate directional incoming radiance instead of irradiance. The incoming radiance at a point is represented by a vector of coefficients with respect to a hemispherical or spherical basis. The surfaces suitable for interpolation are selected automatically according to the roughness of their BRDF. We also propose a novel method for computing translational radiance gradient at a point. 相似文献
189.
Ram Kumar Agarwal Jitka Horsk Jaroslav Stejskal Otakar Quadrat Pavel Kratochvíl Pavel Hudec 《应用聚合物科学杂志》1983,28(11):3453-3466
Samples of industrial high-density polyethylenes (Liten Macro, Liten FB 29, and Hostalen GM 9255 F) were divided into fractions by precipitation fractionation. The original samples and their fractions were characterized by light scattering, GPC, and viscometry. For all samples the molecular weight distribution is of logarithmic-normal type. High-density polyethylenes under investigation contain also high-molecular-weight fractions of pronouncedly branched structure, the content of branched molecules being, of course, considerably smaller than that in low-density polyethylenes. 相似文献
190.
Relationship between structural parameters of poly(ethylene terephthalate) (PET) fibers, their mechanical properties, and nonisothermal sorption of disperse dyes are investigated. Influence of diethylene glycol (DEG) addition and small changes in draw ratio are studied. Mechanical properties are characterized by stress–strain curves at constant deformation rate. The stress–strain relationships are described by means of derivative analysis. For treatment of nonisothermal experiments a simple kinetic model is suggested enabling to determine activation parameters of sorption. Further, the influence of a blank dye bath on the structure and properties of PET fibers is studied. 相似文献