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991.
Ivana Vobornik Anan Bari Sarkar Libo Zhang Danil W. Boukhvalov Barun Ghosh Lesia Piliai Chia-Nung Kuo Debashis Mondal Jun Fujii Chin Shan Lue Mykhailo Vorokhta Huaizhong Xing Lin Wang Amit Agarwal Antonio Politano 《Advanced functional materials》2021,31(52):2106101
The emergence of Dirac semimetals has stimulated growing attention, owing to the considerable technological potential arising from their peculiar exotic quantum transport related to their nontrivial topological states. Especially, materials showing type-II Dirac fermions afford novel device functionalities enabled by anisotropic optical and magnetotransport properties. Nevertheless, real technological implementation has remained elusive so far. Definitely, in most Dirac semimetals, the Dirac point lies deep below the Fermi level, limiting technological exploitation. Here, it is shown that kitkaite (NiTeSe) represents an ideal platform for type-II Dirac fermiology based on spin-resolved angle-resolved photoemission spectroscopy and density functional theory. Precisely, the existence of type-II bulk Dirac fermions is discovered in NiTeSe around the Fermi level and the presence of topological surface states with strong (≈50%) spin polarization. By means of surface-science experiments in near-ambient pressure conditions, chemical inertness towards ambient gases (oxygen and water) is also demonstrated. Correspondingly, NiTeSe-based devices without encapsulation afford long-term efficiency, as demonstrated by the direct implementation of a NiTeSe-based microwave receiver with a room-temperature photocurrent of 2.8 µA at 28 GHz and more than two orders of magnitude linear dynamic range. The findings are essential to bringing to fruition type-II Dirac fermions in photonics, spintronics, and optoelectronics. 相似文献
992.
Martínez-Colón Antonio Viciana-Abad Raquel Perez-Lorenzo Jose Manuel Evers Christine Naylor Patrick A. 《Multimedia Tools and Applications》2022,81(3):3327-3350
Multimedia Tools and Applications - Improving the ability to interact through voice with a robot is still a challenge especially in real environments where multiple speakers coexist. This work has... 相似文献
993.
Cmara Javier Troya Javier Vallecillo Antonio Bencomo Nelly Calinescu Radu Cheng Betty H. C. Garlan David Schmerl Bradley 《Software and Systems Modeling》2022,21(4):1277-1294
Software and Systems Modeling - The problem of mitigating uncertainty in self-adaptation has driven much of the research proposed in the area of software engineering for self-adaptive systems in... 相似文献
994.
Daniele Carnevale Corrado Possieri Antonio Tornambè 《IEEE/CAA Journal of Automatica Sinica》2018,5(3):691-698
In this paper, it is shown that the performances of a class of high-gain practical observers can be improved by estimating the time derivatives of the output up to an order that is greater than the dimension of the system, which is assumed to be in observability form and, possibly, time-varying. Such an improvement is achieved without increasing the gain of the observers, thus allowing their use in a wide variety of control and identification applications. 相似文献
995.
In this paper, the single-gene regulatory system for the lac operon is considered and a method to build a Boolean network able to represent its dynamics is given. A procedure, based on techniques borrowed from algebraic geometry, to compute an optimal control policy minimising a cost function is given for such a Boolean network. A tool to apply such an optimal control policy to the continuous-time system is reported. The proposed control method is tested in two simulative examples. 相似文献
996.
For a fixed set of physico-chemical parameters, an isothermal substrate-inhibited enzyme reaction in a tubular reactor with axial dispersion can give rise to multiple steady states. Criteria previously developed for non-isothermal reactions are applied to this case to develop analytic conditions which ensure uniqueness of steady states. The criteria compare well with values obtained from exact numerical calculations. 相似文献
997.
998.
Sandra H. Gianturco Christopher J. Packard James Shepherd Louis C. Smith Alberico L. Catapano Harley D. Sybers Antonio M. Gotto Jr. 《Lipids》1980,15(6):456-463
Our previous studies showed that hypertriglyceridemic very low density lipoproteins (HTG VLDL) are functionally abnormal.
HTG VLDL, but not normal VLDL, suppress HMG-CoA reductase in cultured normal human fibroblasts. To determine if the suppression
by HTG VLDL resulted from a subpopulation of smaller suppressive particles, more homogeneous subclasses of VLDL-VLDL1 (Sf 100–400), VLDL2 (Sf 60–100), and VLDL3 (Sf 20–60) were obtained from the d<1.006 (g°ml−1) fraction of normal and hypertriglyceridemic plasma by flotation through a discontinuous salt gradient and tested for suppression
in normal human fibroblasts. VLDL1 and VLDL2 from each of the 12 normolipemic subjects tested failed to suppress HMG-CoA reductase activity in normal fibroblasts. Eleven
out of 12 preparations of normal VLDL3 suppressed HMG-CoA reductase, but only one-third as effectively as LDL. By contrast, the VLDL1, VLDL2 and VLDL3 from 15 out of 17 hypertriglyceridemic patients (hyperlipoproteinemia Types IIb, III, IV and V) were highly effective in
suppression, with half-maximal suppression at 0.1–2.0 μg VLDL protein/ml. The VLDL abnormality is apparently associated with
hypertriglyceridemia and not hypercholesterolemia, since VLDL from a homozygous familial hypercholesterolemia patient with
a Type IIa pattern did not suppress whereas each of the VLDL subclasses from a Type IIb patient suppressed. Suppression by
HTG VLDL in normal cells is apparently a consequence of interaction of the protein portion of the VLDL with the specific LDL
cell surface receptor since HTG VLDL1 treated with 0.1 M 1,2-cyclohexanedione to block arginyl residues failed to suppress the enzyme. Moreover, hypertriglyceridemic
Sf 60–400 VLDL failed to suppress HMG-CoA reductase activity in LDL receptor-negative fibroblasts. There were no consistent
major compositional differences between comparable normal and hypertriglyceridemic VLDL subclasses which could account for
differences in suppression. All VLDL subclasses from Type III subjects were enriched in cholesteryl esters and depleted in
triglyceride, relative to the corresponding normal VLDL subclasses. However, Type IV and Type V VLDL subclasses were normal
in this repect. We conclude from these studies that small particle diameter is not required for suppression, since HTG VLDL1 and VLDL2 which contained few, if any, small particles were effective in suppression.
Presented as part of the symposium “Low Density and Very Low Density Lipoproteins” at the American Oil Chemists' Society meeting
on May 2, 1979, in San Francisco. 相似文献
999.
Joan Guillem Mayans Helena Armengol-Relats Dr. Pilar Calleja Prof. Antonio M. Echavarren 《Israel journal of chemistry》2018,58(5):639-658
Gold(I)-catalyzed cycloisomerizations of 1,n-enynes proceed through electrophilic intermediates that can be trapped intra- or intermolecularly by a variety of hetero- and carbon nucleophiles to form complex skeletons in a single step. This review covers the efforts of our group towards the development of new reactions that have been successfully applied in the total synthesis of several natural terpenoids and related carbocyclic structures, as well as for the ready access to challenging linear acenes. 相似文献
1000.
Growth Hormone Secretagogue (A233) Improves Growth and Changes the Tissue Fatty Acid Profile in Juvenile Tilapia (Oreochromis niloticus) 下载免费PDF全文
Rebeca Martínez Carmen Morales Amilcar Arenal Antonio Morales Fidel Herrera Víctor González Mario Pablo Estrada 《Lipids》2018,53(4):429-436
Growth hormone (GH) release is a process that is well regulated by several factors, including GH secretagogues. GH can mediate the regulation of the fatty acid level and composition. The aim of this study was to determine the effect of a synthetic GH secretagogue peptide (A233) on the growth and fatty acid composition in tilapia (Oreochromis niloticus). To address this objective, we administrated a diet supplemented with A233 to juvenile tilapia for 60 days. The group fed with a diet supplemented with 600 μg of A233 per kg of feed increased in weight (4.81 ± 0.09 g) and specific growth rate (2.49 ± 0.03%/day) compared to the control diet group (3.63 ± 0.08 g, 2.07 ± 0.04%/day; respectively) (p < 0.001). In the muscle, the total lipids for the control diet group were higher than that in the group fed with 600 μg of A233 per kg feed; however, no differences were detected in the liver. In both tissues, the patterns of fatty acid composition and content were generally similar, with some exceptions. Tilapia fed with 600 μg of A233 per kg of feed showed, in liver and muscle, a significantly higher composition and content of n‐3 polyunsaturated fatty acids (such as 20:5n‐3, 22:5n‐3, 22:6n‐3) and n‐3/n‐6 PUFA than animals fed with the control diet. To our knowledge, this is the first report on the the effects of natural or synthetic GH secretagogues (GHS) on fatty acid composition, implying an increase in the nutritional quality of the tilapia. 相似文献