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Nutrient Cycling in Agroecosystems - Soil P testing has been widely used to predict crop yields, P uptake, and fertilizer demands in agriculture. Diffusive gradients in thin films (DGT) provides a...  相似文献   
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Manufacturing programmable materials, whose mechanical properties can be adapted on demand, is highly desired for their application in areas ranging from robotics, to biomedicine, or microfluidics. Herein, the inclusion of dynamic and living bonds, such as alkoxyamines, in a printable formulation suitable for two-photon 3D laser printing is exploited. On one hand, taking advantage of the dynamic covalent character of alkoxyamines, the nitroxide exchange reaction is investigated. As a consequence, a reduction of the Young´s Modulus by 50%, is measured by nanoindentation. On the other hand, due to its “living” characteristic, the chain extension becomes possible via nitroxide mediated polymerization. In particular, living nitroxide mediated polymerization of styrene results not only in a dramatic increase of the volume (≈8 times) of the 3D printed microstructure but also an increase of the Young's Modulus by two orders of magnitude (from 14 MPa to 2.7 GPa), while maintaining the shape including fine structural details. Thus, the approach introduces a new dimension by enabling to create microstructures with dynamically tunable size and mechanical properties.  相似文献   
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In this report we present for the first time strong evidence for autosomal-dominant inheritance of grant liver hemangiomas. Furthermore, we review the current literature about incidence, pathogenesis, clinics, as well as diagnostic and therapeutic aspects of LH. A large family of Italian origin is described where three female patients in three successive generations suffered from large symptomatic LH. In addition, two other female relatives exhibited asymptomatic LH on sonographic scans. The restriction of the disease to the female gender could be explained by a sex-dependent difference in penetrance or expressivity of a presumable "liver-hemangioma" gene, or by known proliferative factors such as female sex hormones. We also observed an increased incidence of adenomas of the thyroidea among members with or without LH of the presented family. This uncommon familial association has also not yet been described and its genetic aspects are discussed.  相似文献   
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Sphingolipid metabolism and cell growth regulation   总被引:2,自引:0,他引:2  
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The application of highly effective microstructured devices in continuous production and industrial environments is frequently prone to fouling. A new method is presented to characterize fouling in these microstructures. Thermal fouling of aqueous solutions containing whey protein were used as a test system. Different fouling effects could be observed and distinguished. Integral fouling indicators, such as thermal fouling resistance and pressure drop, as conventional criteria for the occurrence of fouling were compared with direct local optical observation. Low thermal fouling resistances could be detected.  相似文献   
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The clustering of spatio-temporal patterns are essential for many applications. Established from the biological analogy of the cortex, the parametrically coupled logistic map network (PCLMN) provides a viable solution to the clustering problem. To engineer for a single-chip spatio-temporal pattern clustering system, the highly modular PCLMN is designed in analog circuit. In this paper, the 0.6 μm 5 V CMOS design of the processing element is presented. The analog design employs self-calibration techniques to improve the accuracy and robustness of the nonlinear circuits. A fabricated element covers a die area of 0.55 mm2, and consumes 240 mW power at 5 V supply. After calibration, simulation and testing results show that the element fulfills the system-level requirement of the Cort-X model for driving signals up to 1 MHz.  相似文献   
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