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121.
Alessio Petrozziello Guido Cervone Pasquale Franzese Sue Ellen Haupt Raffaele Cerulli 《Applied Artificial Intelligence》2017,31(2):119-133
A genetic algorithm is paired with a Lagrangian puff atmospheric model to reconstruct the source characteristics of an atmospheric release. Observed meteorological and ground concentration measurements from the real-world Dipole Pride controlled release experiment are used to test the methodology. A sensitivity study is performed to quantify the relative contribution of the number and location of sensor measurements by progressively removing them. Additionally, the importance of the meteorological measurements is tested by progressively removing surface observations and vertical profiles. It is shown that the source term reconstruction can occur also with limited meteorological observations. The proposed general methodology can be applied to reconstruct the characteristics of an unknown atmospheric release given limited ground and meteorological observations. 相似文献
122.
Alessio Gizzi Anna Pandolfi Marcello Vasta 《International Journal for Computational Methods in Engineering Science and Mechanics》2016,17(3):143-155
Elastic-electroactive biological media are sensitive to both mechanical and electric forces. Their active behavior is often associated with the presence of reinforcing fibers and their excitation-contraction coupling is due to the interplay between the passive elastic tissue and the active muscular network. In this paper we focus on the theoretical framework of constitutive equations for viscous electroactive media. The approach is based on the additive decomposition of the Helmholtz free energy accompanied to the multiplicative decomposition of the deformation gradient in elastic, viscous and active parts. We describe a thermodynamically sound scenario that accounts for geometric and material nonlinearities. 相似文献
123.
Surface-enhanced Raman scattering (SERS) has been employed for the first time to characterize nano-sized organic carbon (NOC) particles produced in ordinary combustion processes. Ag-coated glass microparticles, used as SERS substrate, provide a Raman scattering cross section enhancement up to five orders of magnitude, which allows sample investigation at low concentration level. The observed spectral features supply a deeper insight on the chemical properties of the investigated combustion product. In addition, the high sensitivity of the SERS technique might be useful to test and characterize the toxicity of NOC particles. 相似文献
124.
F. Gontad A. Lorusso G. Gatti M. Ferrario L. Gioia Passione L. Persano N.Lovergine A. Perrone 《材料科学技术学报》2014,30(1):37-40
This work deals with the deposition of lead(Pb) thin films by the U V pulsed laser ablation technique,for their further use as photocathode devices in superconducting radio frequency guns.Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si(100) and Nb substrates.The films showed a granular structure with a nearly fully covered surface only for that one deposited on Nb substrata X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along(111) planes.Results of the photoemission performance of Pb thin film deposited on Nb substrate showed a very encouraging average value of quantum efficiency of 6×10~(-5) through a single-photon absorption process,promoting further studies in the realisation of Pb photocathodes by this techniqua 相似文献
125.
This letter focuses on a possible pitfall that can occur in the DFT calculation of graphite–hydrogen interactions under tokamaks conditions. Calculations based on the BLYP functional, in fact, result in a stable –C2H3 group that other functionals (OLYP, XLYP, PBE and BP) do not confirm. 相似文献
126.
Alessio E 《Chemical reviews》2004,104(9):4203-4242
127.
Stefan Kroll Alessio Fenu Tom Wambecq Marjoleine Weemaes Jan Van Impe Patrick Willems 《Urban Water Journal》2018,15(4):362-370
An extension of the frequently applied equal filling degree control algorithm is proposed for integrated control of sewer system and wastewater treatment plant (WWTP). Under dry weather conditions (DWC), this control synchronizes sewer storage volume activation at pumping stations (PS) throughout the sewer system with the intermittent aeration at the WWTP. This is in contrast with the frequently advocated influent load equalization at WWTPs. The concept is demonstrated on a case study using an integrated system composed of detailed models for sewer system and WWTP where it reveals considerable potential for energy savings and effluent quality improvement. Moreover, the integrated control allows for the reduction of combined sewer overflows during wet weather events and decreased sedimentation potential in the sewer system. Neither weather predictions nor structural changes at the WWTP or in the sewer system are required. The control concept is applicable to about 50 Flemish WWTPs. 相似文献
128.
Veronika A. Myasoedova Tatyana V. Kirichenko Alexandra A. Melnichenko Varvara A. Orekhova Alessio Ravani Paolo Poggio Igor A. Sobenin Yuri V. Bobryshev Alexander N. Orekhov 《International journal of molecular sciences》2016,17(8)
The risk of cardiovascular disease and atherosclerosis progression is significantly increased after menopause, probably due to the decrease of estrogen levels. The use of hormone replacement therapy (HRT) for prevention of cardiovascular disease in older postmenopausal failed to meet expectations. Phytoestrogens may induce some improvements in climacteric symptoms, but their effect on the progression of atherosclerosis remains unclear. The reduction of cholesterol accumulation at the cellular level should lead to inhibition of the atherosclerotic process in the arterial wall. The inhibition of intracellular lipid deposition with isoflavonoids was suggested as the effective way for the prevention of plaque formation in the arterial wall. The aim of this double-blind, placebo-controlled clinical study was to investigate the effect of an isoflavonoid-rich herbal preparation on atherosclerosis progression in postmenopausal women free of overt cardiovascular disease. One hundred fifty-seven healthy postmenopausal women (age 65 ± 6) were randomized to a 500 mg isoflavonoid-rich herbal preparation containing tannins from grape seeds, green tea leaves, hop cone powder, and garlic powder, or placebo. Conventional cardiovascular risk factors and intima-media thickness of common carotid arteries (cIMT) were evaluated at the baseline and after 12 months of treatment. After 12-months follow-up, total cholesterol decreased by 6.3% in isoflavonoid-rich herbal preparation recipients (p = 0.011) and by 5.2% in placebo recipients (p = 0.020); low density lipoprotein (LDL) cholesterol decreased by 7.6% in isoflavonoid-rich herbal preparation recipients (p = 0.040) and by 5.2% in placebo recipients (non-significant, NS); high density lipoprotein (HDL) cholesterol decreased by 3.4% in isoflavonoid-rich herbal preparation recipients (NS) and by 4.5% in placebo recipients (p = 0.038); triglycerides decreased by 6.0% in isoflavonoid-rich herbal preparation recipients (NS) and by 7.1% in placebo recipients (NS). The differences between lipid changes in the isoflavonoid-rich herbal preparation and placebo recipients did not reach statistical significance (p > 0.05). Nevertheless, the mean cIMT progression was significantly lower in isoflavonoid-rich herbal preparation recipients as compared to the placebo group (6 μm, or <1%, versus 100 μm, or 13%; p < 0.001 for the difference). The growth of existing atherosclerotic plaques in isoflavonoid-rich herbal preparation recipients was inhibited by 1.5-fold (27% versus 41% in the placebo group). The obtained results demonstrate that the use of isoflavonoid-rich herbal preparation in postmenopausal women may suppress the formation of new atherosclerotic lesions and reduce the progression of existing ones, thus promising new drug for anti-atherosclerotic therapy. Nevertheless, further studies are required to confirm these findings. 相似文献
129.
Dr. Alvin W. Hung Dr. H. Leonardo Silvestre Dr. Shijun Wen Dr. Guillaume P. C. George Dr. Jennifer Boland Prof. Tom L. Blundell Dr. Alessio Ciulli Prof. Chris Abell 《ChemMedChem》2016,11(1):38-42
Ligand efficiency has proven to be a valuable concept for optimization of leads in the early stages of drug design. Taking this one step further, group efficiency (GE) evaluates the binding efficiency of each appendage of a molecule, further fine‐tuning the drug design process. Here, GE analysis is used to systematically improve the potency of inhibitors of Mycobacterium tuberculosis pantothenate synthetase, an important target in tuberculosis therapy. Binding efficiencies were found to be distributed unevenly within a lead molecule derived using a fragment‐based approach. Substitution of the less efficient parts of the molecule allowed systematic development of more potent compounds. This method of dissecting and analyzing different groups within a molecule offers a rational and general way of carrying out lead optimization, with potential broad application within drug discovery. 相似文献
130.