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排序方式: 共有313条查询结果,搜索用时 31 毫秒
61.
In recent years, several intensive studies have been carried out in order to reduce the energy consumption of buildings. One solution lies on whole building energy simulation that permits to enable the heat (and moisture) transfer through the building envelope and, consequently, is a way to understand how to improve the building performance. This article aims to analyze the modeling level needed to successfully evaluate the heat transfer through glazing parts of windows in such whole-building simulations as it is well-known that windows are the thermally weakest elements of the building envelope. 相似文献
62.
C. Tonda-Turo E. Cipriani S. Gnavi V. Chiono C. Mattu P. Gentile I. Perroteau M. Zanetti G. Ciardelli 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2723-2735
Gelatin (GL) nanofibrous matrices mimicking the complex biological structure of the natural extracellular matrix (ECM) were prepared from aqueous solutions by electrospinning technique. GL nanofibres with a diameter size of around 300 nm were obtained optimising the process and solution parameters. To increase the GL stability in aqueous environment γ-glycidoxypropyltrimethoxysilane (GPTMS) was used as GL crosslinker. GPTMS crosslinking did not modify the nanofibrous matrix morphology: fibre diameter and membrane pores size were 327 ± 45 nm and 1.64 ± 0.37 μm, respectively. The produced GPTMS crosslinked GL nanofibres (GL/GPTMS_NF) were found to support the in vitro adhesion, proliferation and survival of neonatal olfactory bulb ensheating cells (NOBECs). 相似文献
63.
Nathan Mendes Rogério M. Barbosa Roberto Zanetti Freire Ricardo C. L. F. Oliveira 《Building Simulation》2008,1(2):129-143
Due to the lack of a building simulation program that can simulate in details the combined heat, vapor, and liquid transfer
in porous elements and the HVAC (heating, ventilation and air-conditioning) systems, a flexible computational algorithm has
been elaborated in order to integrate models for both HVAC systems and multizone hygrothermal building model. In the algorithm,
models for the primary system-composed of chiller, cooling tower, primary pumps, and condensation pumps—have been described.
For the secondary system, models for the cooling and dehumidifying coil, humidifier, fan, and mixing box have been considered.
Those mathematical models have been integrated into the whole-building PowerDomus simulation environment. The simulation environment
is presented, and results show the usability aspects of the proposed computer environment by comparing air- and water-cooled
equipment. 相似文献
64.
L Tamborini A Pinto TK Smith LL Major MC Iannuzzi S Cosconati L Marinelli E Novellino L Lo Presti PE Wong MP Barrett C De Micheli P Conti 《ChemMedChem》2012,7(9):1623-1634
Acivicin analogues with an increased affinity for CTP synthetase (CTPS) were designed as potential new trypanocidal agents. The inhibitory activity against CTPS can be improved by increasing molecular complexity, by inserting groups able to establish additional interactions with the binding pocket of the enzyme. This strategy has been pursued with the synthesis of α‐amino‐substituted analogues of Acivicin and N1‐substituted pyrazoline derivatives. In general, there is direct correlation between the enzymatic activity and the in vitro anti‐trypanosomal efficacy of the derivatives studied here. However, this cannot be taken as a general rule, as other important factors may play a role, notably the ability of uptake/diffusion of the molecules into the trypanosomes. 相似文献
65.
Marica Consolini Michela Sega Chiara Zanetti Marina Fusi Roberto Chignola Marco De Carli Corrado Rizzi Gianni Zoccatelli 《Food Analytical Methods》2012,5(2):234-243
Wheat α-amylase inhibitors (α-AIs) are known anti-nutritional factors, respiratory allergens, and they can sporadically cause
food allergy. α-AIs are therefore expected to reach the enteric mucosae in an immunologically active form, but information
on their stability to gastric digestion is not available. Resistance to pepsinolysis is nonetheless a key factor for any food
allergen. We therefore investigated whether α-AIs could resist pepsin digestion in simulated gastric fluids (SGF) and in emulsified
SGF, the latter simulating more realistically the multi-phase nature of stomach bolus. Since α-AIs comprise a huge family
of proteins, we investigated 0.19 α-AI as a prominent member. The digestion patterns were analyzed by immunoblotting using
anti-0.19 polyclonal antibodies and sera from wheat allergic patients sensitized to 0.19 α-AI. The results show that the immune
epitopes of α-AI are detectable up to 120 min of digestion in emulsifying conditions. Intra-molecular disulfide bonds and,
in particular, emulsification were found to be crucial factors for protein stability. The results show that 0.19 α-AI must
be considered a potential food allergen. 相似文献
66.
67.
G. Gottardi R. Bartali V. Micheli V. Guarnieri I. Luciu P. Pu R. Pandiyan N. Laidani 《Surface & coatings technology》2011
Fundamental and applied investigation of ZnO has been recently experiencing a renaissance due to its prospective use in various technological domains and, in particular, as transparent conductive oxide (TCO). In this respect, the present work aims to study the structural and physical properties of ZnO thin films deposited by RF sputtering in pure Ar and Ar–H2 plasmas, at various concentrations (0–50%). The plasma chemical species were followed in function of the different gas mixture settings by optical emission spectroscopy (OES). X-ray photoelectron spectroscopy (XPS) and ATR-FTIR (Attenuated Total Reflection Fourier-Transformed Infrared) spectroscopy were used to study the bulk and surface chemical composition of the films, X-ray Diffraction (XRD) analysis allowed lattice structure and grain size determination while samples morphology was checked with a scanning electron microscope (SEM). The films were also characterized for their electrical and optical properties.The introduction of hydrogen in the plasma phase strongly affected the structural, chemical and physical properties of the films. In particular a pronounced change in the film electrical behavior was observed which become conductive when H is added in the gas mixture ([H2] > 6%). The film transparency was on the other hand maintained. By combining XPS, ATR-FTIR and OES data we could correlate the established conductivity and its variations with intentional hydrogen incorporation in the crystal structure in the form of hydroxide species. 相似文献
68.
This paper presents a microwave characterization of several carbon-based composite materials interesting the future aircraft/aerospace systems. They consist in epoxy resin reinforced with five different carbon species: micro-sized granular graphite, fullerenes, carbon nanofibers, single- and multi-walled carbon nanotubes. Main goal of this work is to show how carbon inclusions size and geometry are able to significantly modify the electromagnetic properties at microwave frequencies. Microwave characterization is performed in terms of microwave permittivity and intrinsic wave impedance evaluation; all the computations are based on microwave scattering parameters measured in the X-band (8.2/12.4 GHz) by waveguide method. A theoretical analysis of the microwave absorbing capability is then performed assuming that a multilayer of nanocomposite material was backed on a conductor plate (such a structure is typically called Radar Absorbing Material). The results obtained for the reflection coefficient indicate that nanoparticles give better absorption properties to the matrix than micro-sized ones: nanocomposite materials could thus be used successfully as microwave absorbers, not only for their absorption performances but also for their light weight. 相似文献
69.
Semeria L. Sato K. De Micheli G. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2001,9(6):743-756
One of the greatest challenges in a C/C++-based design methodology is efficiently mapping C/C++ models into hardware. Many networking and multimedia applications implemented in hardware or mixed hardware/software systems now use complex data structures stored in multiple memories, so many C/C++ features that were originally designed for software applications are now making their way into hardware. Such features include dynamic memory allocation and pointers for managing data. We present a solution for efficiently mapping arbitrary C code with pointers and malloc/free into hardware. Our solution, which fits current memory management methodologies, instantiates an application-specific hardware memory allocator coupled with a memory architecture. Our work also supports the resolution of pointers without restriction on the data structures. We present an implementation based on the SUIF framework along with case studies such as the realization of a video filter and an ATM segmentation engine 相似文献
70.
Laura Micheli Lara Testai Andrea Angeli Donatello Carrino Alessandra Pacini Francesco Margiotta Lorenzo Flori Claudiu T. Supuran Vincenzo Calderone Carla Ghelardini Lorenzo Di Cesare Mannelli 《International journal of molecular sciences》2022,23(11)
Neuropathy development is a major dose-limiting side effect of anticancer treatments that significantly reduces patient’s quality of life. The inadequate pharmacological approaches for neuropathic pain management warrant the identification of novel therapeutic targets. Mitochondrial dysfunctions that lead to reactive oxygen species (ROS) increase, cytosolic Ca2+ imbalance, and lactate acidosis are implicated in neuropathic pain pathogenesis. It has been observed that in these deregulations, a pivotal role is played by the mitochondrial carbonic anhydrases (CA) VA and VB isoforms. Hence, preclinical studies should be conducted to assess the efficacy of two novel selenides bearing benzenesulfonamide moieties, named 5b and 5d, and able to inhibit CA VA and VB against paclitaxel-induced neurotoxicity in mice. Acute treatment with 5b and 5d (30–100 mg/kg, per os – p.o.) determined a dose-dependent and long-lasting anti-hyperalgesic effect in the Cold plate test. Further, repeated daily treatment for 15 days with 100 mg/kg of both compounds (starting the first day of paclitaxel injection) significantly prevented neuropathic pain development without the onset of tolerance to the anti-hyperalgesic effect. In both experiments, acetazolamide (AAZ, 100 mg/kg, p.o.) used as the reference drug was partially active. Moreover, ex vivo analysis demonstrated the efficacy of 5b and 5d repeated treatments in reducing the maladaptive plasticity that occurs to glia cells in the lumbar portion of the spinal cord and in improving mitochondrial functions in the brain and spinal cord that were strongly impaired by paclitaxel-repeated treatment. In this regard, 5b and 5d ameliorated the metabolic activity, as observed by the increase in citrate synthase activity, and preserved an optimal mitochondrial membrane potential (ΔΨ) value, which appeared depolarized in brains from paclitaxel-treated animals. In conclusion, 5b and 5d have therapeutic and protective effects against paclitaxel-induced neuropathy without tolerance development. Moreover, 5b and 5d reduced glial cell activation and mitochondrial dysfunction in the central nervous system, being a promising candidate for the management of neuropathic pain and neurotoxicity evoked by chemotherapeutic drugs. 相似文献