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31.
The hydrodynamic transport equations for charges in a semiconductor have been solved for a periodic excitation by means of a harmonic approach, in order to model microwave and millimetre-wave active devices. The solution is based on the expansion of physical variables in a Fourier series in the time domain, and on discretisation in the space domain. A waveform-balance technique in the TD is used to solve the nonlinear equations system. This approach allows for a longer time step with respect to standard TD solutions for most cases of interest, greatly reducing simulation time by at least two orders of magnitude in typical cases. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14: 36–48, 2004. 相似文献
32.
Injectivity, and existence of a bounded inverse, of Riccati operators is investigated for various classes of systems. A unified approach to this problem, based on few general properties verified by several control systems, is proposed. The relation between the invertibility of Riccati operators and the controllability of certain related systems is pointed out. 相似文献
33.
Hermann Russ Michele Mazzanti Chris Parsons Katrin Riemann Alexander Gebauer Gerhard Rammes 《International journal of molecular sciences》2022,23(10)
Soluble amyloid β (Aβ) oligomers have been shown to be highly toxic to neurons and are considered to be a major cause of the neurodegeneration underlying Alzheimer’s disease (AD). That makes soluble Aβ oligomers a promising drug target. In addition to eliminating these toxic species from the patients’ brain with antibody-based drugs, a new class of drugs is emerging, namely Aβ aggregation inhibitors or modulators, which aim to stop the formation of toxic Aβ oligomers at the source. Here, pharmacological data of the novel Aβ aggregation modulator GAL-201 are presented. This small molecule (288.34 g/mol) exhibits high binding affinity to misfolded Aβ1-42 monomers (KD = 2.5 ± 0.6 nM). Pharmacokinetic studies in rats using brain microdialysis are supportive of its oral bioavailability. The Aβ oligomer detoxifying potential of GAL-201 has been demonstrated by means of single cell recordings in isolated hippocampal neurons (perforated patch experiments) as well as in vitro and in vivo extracellular monitoring of long-term potentiation (LTP, in rat transverse hippocampal slices), a cellular correlate for synaptic plasticity. Upon preincubation, GAL-201 efficiently prevented the detrimental effect on LTP mediated by Aβ1-42 oligomers. Furthermore, the potential to completely reverse an already established neurotoxic process could also be demonstrated. Of particular note in this context is the self-propagating detoxification potential of GAL-201, leading to a neutralization of Aβ oligomer toxicity even if GAL-201 has been stepwise removed from the medium (serial dilution), likely due to prion-like conformational changes in Aβ1-42 monomer aggregates (trigger effect). The authors conclude that the data presented strongly support the further development of GAL-201 as a novel, orally available AD treatment with potentially superior clinical profile. 相似文献
34.
Franco Cataldo Giuseppe A. Baratta Giovanni Strazzulla 《Fullerenes, Nanotubes and Carbon Nanostructures》2002,10(3):197-206
C60 fullerene films have been bombarded with He+ ions at 30 keV at room temperature in vacuum. The structural changes undergone by C60 have been followed by both FT-IR and Raman spectroscopy. Raman spectroscopy was the most useful tool for this scope. It has been clearly discovered that at low radiation dose C60 forms oligomers but at higher radiation doses it is converted into an amorphous carbonaceous matter. The implications of these results on the possible survival of C60 fullerene in the interstellar space have been discussed briefly in connection with the previous results on the effects of various types of electromagnetic radiation over C60. 相似文献
35.
Carlos Garcia-Padilla Estefanía Lozano-Velasco María del Mar Muoz-Gallardo Juan Manuel Castillo-Casas Sheila Cao-Carrillo Francisco Jos Martínez-Amaro Virginio García-Lpez Amelia Arnega Diego Franco Virginio García-Martínez Carmen Lpez-Snchez 《International journal of molecular sciences》2022,23(15)
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma. 相似文献
36.
Rapid urbanization, climate change and energy security warrant a more detailed understanding of how cities today consume energy. Agent-based, integrated microsimulation models of urban systems provide an excellent platform to accomplish this task, as they can capture both the short- and long-term decisions of firms and households which directly affect urban energy consumption. This paper presents the current effort towards developing an urban energy model for the Integrated Land Use, Transportation, Environment (ILUTE) modelling system. 相似文献
37.
Franco Bisceglie Giorgio Pelosi Nicol Orsoni Marianna Pioli Mauro Carcelli Paolo Pelagatti Silvana Pinelli Peter J. Sadler 《International journal of molecular sciences》2022,23(14)
We report the synthesis and characterization of three half-sandwich Ru(II) arene complexes [(η6-arene)Ru(N,N′)L][PF6]2 containing arene = p-cymene, N,N′ = bipyridine, and L = pyridine meta- with methylenenaphthalimide (C1), methylene(nitro)naphthalimide (C2), or methylene(piperidinyl)naphthalimide (C3). The naphthalimide acts as an antenna for photoactivation. After 3 h of irradiation with blue light, the monodentate pyridyl ligand had almost completely dissociated from complex C3, which contains an electron donor on the naphthalimide ring, whereas only 50% dissociation was observed for C1 and C2. This correlates with the lower wavelength and strong absorption of C3 in this region of the spectrum (λmax = 418 nm) compared with C1 and C2 (λmax = 324 and 323 nm, respectively). All the complexes were relatively non-toxic towards A549 human lung cancer cells in the dark, but only complex C3 exhibited good photocytoxicity towards these cancer cells upon irradiation with blue light (IC50 = 10.55 ± 0.30 μM). Complex C3 has the potential for use in photoactivated chemotherapy (PACT). 相似文献
38.
Jinghua?LiEmail author Franco?Maloberti 《Analog Integrated Circuits and Signal Processing》2005,45(3):211-217
In this paper, we present a low power 12 bit 5 MSPS, successive approximation converter architecture using pipeline technique.
The converter consumes 4 mW at the Nyquist rate input with 1.8 V power supply. By combination of pipeline and successive architecture,
the entire circuit, simulated at the transistor level in a 0.18 μ CMOS process, achieves a FoM (Figure of Merit) of 0.19 pJ/conversion.
Jinghua Li was born in 1973. He received the MSEE and BSEE Degree from College of Electronics and information, Shanghai Jiaotong University
and Harbin Engineering University in 1997 and 1994 respectively. He is currently pursuing Ph.D degree in Department of Electrical
Engineering, Texas A&M University, College Station, TX, USA.
In 1997, he joined Bell Laboratory (China), Lucent Technologies as a member of technical staff. He worked on single-chip HDTV
decoder IC and Sonet/SDH SoC for various projects in Murray Hill, NJ, USA and Shanghai China. He also finished projects on
hardware implementation of Video conference/Phone based on H.263 standard as his master thesis. Since 2000, he has been a
research assistant in Analog Mixed Signal center, TAMU. Most currently his research interests are focused on low power analog
to digital conversion IC design, CMOS implementation of 10 G/2.5 G clock data recovery IC for high speed serial communications.
Franco Maloberti received the Laurea Degree in Physics (Summa cum Laude) from the University of Parma, Parma Italy, in 1968 and the Dr. Honoris
Causa degree in electronics from the Instituto Nacional de Astrofisica, Optica y Electronica (Inaoe), Puebla, Mexico in 1996.
In 1993 he was a Visiting Professor at ETH-PEL, Zurich. He was Professor of Microelectronics and Head of the Micro Integrated
Systems Group University of Pavia, Pavia, Italy and the TI/J.Kilby Analog Engineering Chair Professor at the Texas A&M University.
He is currently the Distinguished Microelectronic Chair Professor at University of Texas at Dallas and part-time Professor
at the University of Pavia, Italy.
His professional expertise is in the design, analysis and characterization of integrated circuits and analogue digital applications,
mainly in the areas of switched capacitor circuits, data converters, interfaces for telecommunication and sensor systems,
and CAD for analogue and mixed A-D design. He has written more than 250 published papers, three books and holds 15 patents.
He was in 1992 recipient of the XII Pedriali Prize for his technical and scientific contributions to national industrial production.
He was co-recipient of the 1996 Institute of Electrical Engineers (U.K.) Fleming Premium for the paper “CMOS Triode Transistor
Transconductor for high-frequency continuous time filters.” He has been responsible at both technical and management levels
for many research programs including ten ESPRIT projects and has served the European Commission as ESPRIT Projects' Evaluator,
Reviewer and as European Union expert in many European Initiatives. He served the Academy of Finland on the assessment of
electronic research in Academic institutions and on the research programs' evaluations.
Dr. Maloberti was Vice-President, Region 8, of the IEEE Circuit and Systems Society from 1995 to 1997 and an Associate Editor
of IEEE-Transaction on Circuit and System-II. He received the 1999 IEEE CAS Society Meritorious Service Award, the 2000 CAS
Society Golden Jubilee Medal, and the IEEE Millenium Medal. He is the President of the IEEE Sensor Council and member of the
Board of Governors of the IEEE CAS Society. He is a member of the Italian Electrothecnical and Electronic Society (AEI), the
Editorial Board of Analog Integrated Circuits and Signal Processing, and Fellow of IEEE. 相似文献
39.
Franco Cataldo 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(2):289-295
Abstract Through a short review on pentalene chemistry, it is discussed the possibility to trap as organometallic complexes unstable fullerenes violating the isolated pentagons rule. 相似文献
40.
Shan He Chris Franco Wei Zhang 《International Journal of Food Science & Technology》2012,47(11):2397-2404
The aim of this study was to develop an enzymatic hydrolysis process of protein co‐products for two major commercial fish species in Australia: Atlantic salmon (AS) and Yellowtail kingfish (YTK). The outcomes are to produce high protein recovery of fish protein hydrolysates within controlled molecular weight ranges that display enhanced physicochemical properties of oil binding and emulsification. Three enzymes (Flavourzyme, Neutrase and Alcalase) were applied to processing co‐products. Protein recovery and physicochemical properties were evaluated with increasing hydrolysis time from 30 min to 180 min and ratio of enzyme to substrate (E/S) from 0.5% to 3.0%. In order to achieve a product with optimum emulsifying capacity (50 ± 0.6 m2 g?1), an E/S ratio of 0.6–1.3% Flavourzyme was applied for 30–111 min with a protein recovery of 55%; in order to achieve a product with optimum oil‐binding capacity (8.3 ± 0.3 g oil g hydrolysates?1), an E/S ratio of 2.3–3.0% Flavourzyme was applied for 25–64 min with a protein recovery of 70%. YTK protein hydrolysates were further membrane‐fractionated into five fractions (>100 kDa, 50–100 kDa, 30–50 kDa, 10–30 kDa and <10 kDa), and of these, the 10–30 kDa exhibited the best properties of oil binding (19 ± 0.3 g oil g hydrolysates?1) and emulsification (57 ± 0.7 m2 g?1). These results demonstrate the importance of enzymatic hydrolysis of seafood co‐products into high‐value ingredients for food products and processing. 相似文献