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991.
992.
Harald Mangge Florian Prüller Sieglinde Zelzer Herwig Ain?dhofer Sabine Pailer Petra Kieslinger Johannes Haybaeck Barbara Obermayer-Pietsch Gerhard Cvirn Hans-Jürgen Gruber 《International journal of molecular sciences》2015,16(7):15776-15784
Clotting abnormalities are discussed both in the context with thyroid dysfunctions and obesity caused by a high fat diet. This study aimed to investigate the impact of hypo-, or hyperthyroidism on the endogenous thrombin potential (ETP), a master indicator of clotting activation, on Sprague Dawley rats fed a normal or high fat diet. Female Sprague Dawley rats (n = 66) were grouped into normal diet (ND; n = 30) and high-fat diet (HFD; n = 36) groups and subdivided into controls, hypothyroid and hyperthyroid groups, induced through propylthiouracil or triiodothyronine (T3) treatment, respectively. After 12 weeks of treatment ETP, body weight and food intake were analyzed. Successfully induced thyroid dysfunction was shown by T3 levels, both under normal and high fat diet. Thyroid dysfunction was accompanied by changes in calorie intake and body weight. In detail, compared to euthyroid controls, hypothyroid rats showed significantly increased—and hyperthyroid animals significantly decreased—ETP levels. High fat diet potentiated these effects in both directions. In summary, we are the first to show that hypothyroidism and high fat diet potentiate the thrombotic capacity of the clotting system in Sprague Dawley rats. This effect may be relevant for cardiovascular disease where thyroid function is poorly understood as a pathological contributor in the context of clotting activity and obesogenic nutrition. 相似文献
993.
994.
995.
Wireless Microfluidic Systems for Programmed,Functional Transformation of Transient Electronic Devices 下载免费PDF全文
Chi Hwan Lee Seung‐Kyun Kang Giovanni A. Salvatore Yinji Ma Bong Hoon Kim Yu Jiang Jae Soon Kim Lingqing Yan Dae Seung Wie Anthony Banks Soong Ju Oh Xue Feng Yonggang Huang Gerhard Troester John A. Rogers 《Advanced functional materials》2015,25(32):5100-5106
Electronic systems that enable programmable transformation of functional behaviors by remote control or by autonomous responses to user‐defined circumstances create unusual engineering opportunities, where physical changes in the hardware induce desired changes in operation. This paper presents materials and device architectures for technologies of this type, in which localized microfluidic chemical etching of targeted constituent components in the electronics occurs in a sequential, selective manner. Custom circuits that include reconfigurable radio‐powered thermal actuators with analog amplifiers and square waveform generators illustrate the concepts. 相似文献
996.
David C. Green Rebecca Boston Stefan Glatzel Martin R. Lees Stuart C. Wimbush Jason Potticary Wataru Ogasawara Simon R. Hall 《Advanced functional materials》2015,25(29):4700-4707
The mechanism of formation of the superconductor Bi2Sr2CaCu2O8+x (Bi‐2212) has been an open question since its discovery in 1988. By controlling crystal growth through the use of biopolymers as multivalent cation chelating agents, it is demonstrated through X‐ray diffraction and thermogravimetric analysis, that it is the formation of a mixed metal carbonate eutectic that promotes the formation of the target phase. X‐ray diffraction experiments, supported by infrared spectroscopy, identify this phase as (Sr1?x Ca x )CO3. This knowledge allows to further reduce the eutectic melting point by the incorporation of a biopolymer rich in potassium ions, resulting in the scalable formation of Bi‐2212 at a temperature 50 °C lower than has been achieved previously. 相似文献
997.
End-sealed 60×60×250?mm3 Pinus radiata pieces were dried at 65/37 °C (dry bulb/wet bulb temperature) and 4 ms-1 air speed to study various drying phenomena above fibre saturation point. While drying, an X-ray computed tomography (CT) scanner captured a cross-cut density image every ten minutes. The density data was used to determine moisture content, rate of moisture loss from the core, wetline (boundary line of the free water region) depth and cross-cut area of the wood pieces. Repeating patterns were observed, which indicated that the cavity-size distribution of the wood pieces dictated fluctuations in the rate of moisture loss from the core and cross-cut area shrinkage during drying in the free water phase. It is hypothesised that, while drying an interconnected capillary network in the free water phase, the largest meniscus penetrates a wood piece through the largest cavities, thus also allowing air into the capillary network. The largest meniscus would always get smaller as it penetrates the wood piece until it is not the largest meniscus in the network anymore. Then the new largest meniscus would start penetrating the capillary network, etc. The largest meniscus would also determine the liquid tension in the capillary network. When the largest meniscus gets small enough, and the liquid tension strong enough, deformation and collapse of the remaining liquid-filled cavities can occur. A large liquid-filled interconnected capillary network would eventually fragment into a number of smaller liquid-filled interconnected networks, at which point a receding wetline could be observed. 相似文献
998.
Ulrich Engelhardt Klaus Peters und Hans Gerhard Maier 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,178(4):288
Zusammenfassung Die Identifizierung von Pyroglutaminsäure in Kaffee durch GC/MS des Di-trimethylsilylderivats wird beschrieben. Pyroglutaminsäure findet sich im Röstkaffee zu 0,5 bis 1,5 g/kg und im Kaffee-Extrakt zu ca. 5 g/kg.
Pyroglutamic acid in coffee
Summary The identification of pyroglutamic acid in coffee by means of gas chromatography/mass spectrometry is described. The contents of this acid are 0.5 to 1,5 g/kg in roast coffee and about 5 g/kg in coffee extracts.相似文献
999.
Olga Fabrichnaya Galina Savinykh Gerhard Schreiber Hans J. Seifert 《Journal of Phase Equilibria and Diffusion》2011,32(4):284-297
Phase equilibria in the ZrO2-Nd2O3-Y2O3 system at 1523-1873 K have been investigated by x-ray diffraction (XRD) and scanning electron microscopy combined with energy
dispersive x-ray spectroscopy (SEM/EDX). Temperatures of phase transformations were determined by differential thermal analysis.
Temperatures of invariant reactions in the ZrO2-Nd2O3 system F = A + Pyr and H = F + A were determined as 1763 and 2118 K respectively and thermodynamic parameters of phases were
re-assessed. Phase transformations in ternary systems were determined at 1732 K for composition ZrO2-48.46Nd2O3-5.38Y2O3 (mol%) and at 1744 and 1881 K for composition ZrO2-79.09Nd2O3-2.75Y2O3 (mol%). They were interpreted using XRD investigation before and after DTA as Pyr + B → F, Pyr → F and A → B, respectively.
The solubility of the Y2O3 in pyrochlore phase was found to exceed 10 mol%. The thermodynamic parameters of the ZrO2-Nd2O3-Y2O3 system were reassessed taking into account solubility of Y2O3 in the Nd2Zr2O7 pyrochlore phase (Pyr). It is assumed that Y3+ substitutes Nd3+ and Zr4+ in their preferentially occupied sublattices. Ternary parameter was introduced into fluorite phase (F) for better reproducing
of phase equilibria. Mixing parameters were reassessed for phase A (Nd2O3 based solution), monoclinic phase B and cubic phase C (Y2O3 based solution). The isothermal sections calculated for the ZrO2-Nd2O3-Y2O3 system are in the reasonable agreement with experimental results. 相似文献
1000.
Harald Rösner Christian Kübel Yulia Ivanisenko Lilia Kurmanaeva Sergiy V. Divinski Martin Peterlechner Gerhard Wilde 《Acta Materialia》2011,59(19):7380-7387
Aberration-corrected transmission electron microscopy was used to provide structural information on a triple junction in nanocrystalline Pd. This triple junction consists of two intersecting Σ3 twin boundaries with a Σ9 grain boundary and is connected to a quadruple point via the Σ9 grain boundary. A comprehensive strain analysis of this triple junction using geometric phase analysis is presented and compared with a molecular dynamics simulation. The main results are: (i) the strain field of the core of the triple junction shows dislocation character and extends over a distance of about 0.5 nm; (ii) the intersecting boundaries result in a net translation of , which corresponds to a Burgers vector of an dislocation in the fcc lattice; (iii) a disclination emerging from the triple junction along the Σ9 grain boundary is balanced by a disclination of opposite sign emerging from the quadruple point. Based on the observation that the core of the triple junction can be described by the strain field of a dislocation, its energy was estimated using to be about 1.7 × 10−9 J m−1. The presence of a disclination dipole is thought to be essential for stabilization of the structure observed. 相似文献