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131.
Dr. Elena Marchesi Dr. Nicola Chinaglia Dr. Massimo L. Capobianco Dr. Paolo Marchetti Tzu-En Huang Hao-Cheng Weng Dr. Jih-Hwa Guh Dr. Lih-Ching Hsu Dr. Daniela Perrone Dr. Maria Luisa Navacchia 《ChemMedChem》2019,14(7):779-787
A series of hybrid compounds based on natural products—bile acids and dihydroartemisinin—were prepared by different synthetic methodologies and investigated for their in vitro biological activity against HL-60 leukemia and HepG2 hepatocellular carcinoma cell lines. Most of these hybrids presented significantly improved antiproliferative activities with respect to dihydroartemisinin and the parent bile acid. The two most potent hybrids of the series exhibited a 10.5- and 15.4-fold increase in cytotoxic activity respect to dihydroartemisinin alone in HL-60 and HepG2 cells, respectively. Strong evidence that an ursodeoxycholic acid hybrid induced apoptosis was obtained by flow cytometric analysis and western blot analysis. 相似文献
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134.
1923 Gleno Dam Break: Case Study and Numerical Modeling 总被引:2,自引:0,他引:2
Marco Pilotti Andrea Maranzoni Massimo Tomirotti Giulia Valerio 《Canadian Metallurgical Quarterly》2011,137(4):480-492
On the morning of December 1, 1923, the Gleno Dam (located in the Central Italian Alps) suddenly collapsed a few days after the first complete reservoir filling. Nearly 4.5×106??m3 of water was released. The consequent inundation caused significant destruction along the downstream valley and a death toll of at least 356 lives. This failure is the only historical case of dam break caused by structural deficiencies that has occurred in Italy. As a result, it has deeply influenced the evolution of Italian regulations regarding dam design and hydraulic risk evaluation. However, in spite of its relevance, this event has never been characterized from a hydraulic standpoint. This paper reports the main information obtained from the analysis of a vast amount of historical documents regarding the Gleno Dam break to set up a case study useful for validating dam-break models in mountain settings. Moreover, it presents the main results of one-dimensional (1D) modeling of the dam break wave propagation accomplished with a first-order finite volume numerical scheme recently proposed in the literature for field applications. The overall effectiveness and reliability of the model are evaluated for this case characterized by very irregular topography. Finally, the practical relevance of several choices that the numerical reconstruction of this kind of event demands is tested. 相似文献
135.
New Approach to Water Distribution Network Calibration 总被引:1,自引:0,他引:1
A new approach is proposed for calibrating hydraulic network models. This procedure uses a nonlinear optimization algorithm along with a standard, off-the-shelf, network solver. Pipe roughness is adjusted until simulation results agree with the values observed in the field. To achieve realistic calibrated roughness values, the objective is to minimize the sum of the squares of the differences between the calibrated and initial pipe roughness estimates, under a set of constraints determined from a sensitivity matrix. The algorithm is applied to a sample network, and the resulting calibrated network is tested under different loading conditions. 相似文献
136.
Connections for composite concrete slab and LVL flooring systems 总被引:1,自引:1,他引:0
Composite concrete slab and timber flooring systems are commonly used in many parts of the world to exploit the high strength-to-weight
ratio of timber and the good acoustic separation provided by concrete floor slabs. This paper describes the results of an
experimental programme that investigated the suitability of a range of connectors to transfer shear between a concrete slab
and a laminated veneer lumber (LVL) beam. Shear tests on reduced scale specimens were performed with the aim of comparing
the strength, stiffness, and post-peak performance of different connectors such as round and rectangular concrete plugs with
and without screw and steel pipe reinforcement, proprietary (SFS) screws, coach screws with different diameters, sheet brace
anchors, and framing brackets. The rectangular concrete plug reinforced with a coach screw was found to provide the greatest
stiffness and strength, as well as favourable post-peak behaviour. Such a system can be used for cost-effective composite
floor systems due to its efficient cost-to-capacity ratio, which reduces the number of connectors needed along the beam axis
to achieve the composite action. 相似文献
137.
Ilona BOBEK Dehua GONG Massimo DE CAL Dinna CRUZ Chang Y. CHIONH Mikko HAAPIO Sachin S. SONI Federico NALESSO Paolo LENTINI Francesco GARZOTTO Valentina CORRADI Claudio RONCO 《Hemodialysis international. International Symposium on Home Hemodialysis》2010,14(3):302-307
Neutrophil gelatinase‐associated lipocalin (NGAL) protein is an early biomarker for acute kidney injury (AKI). It is unknown if extracorporeal therapies (EC) have an effect on circulating NGAL levels. This study was designed to describe the kinetics of NGAL molecule in different EC techniques and to evaluate NGAL clearance in different operational conditions. A mock hemofiltration (HF) and hemoperfusion (HP) setup was used. NGAL was added to the blood reservoir and then measured at 30‐minute intervals from arterial, venous, and ultrafiltrate (UF) lines. Removal kinetics and NGAL sieving coefficient were calculated. In our experiments, baseline NGAL concentration averaged 452 μg/L. There was a consistent downward trend throughout the experiment. NGAL concentration in the UF was between 80 and 90 μg/L, though it showed a slight increase in the second hour. The sieving coefficient of NGAL ranged from 0.2 to 0.4 during HF and it appeared to increase with time, suggesting an initial effect of membrane adsorption. HP proved clearly that there was adsorption of NGAL by the membrane and the point of saturation occured at approximately 60 minutes from the start of circulation. Our evaluation demonstrates that NGAL can be adsorbed and ultrafiltrated with polysulfone membranes. This should be taken into consideration when using NGAL as an AKI biomarker in patients undergoing EC circulation. 相似文献
138.
Deployment of RSS-Based Indoor Positioning Systems 总被引:1,自引:0,他引:1
Christian Esposito Massimo Ficco 《International Journal of Wireless Information Networks》2011,18(4):224-242
Location estimation based on Received Signal Strength (RSS) is the prevalent method in indoor positioning. For such positioning
systems, a massive collection of training samples is needed for their calibration. The accuracy of these methods is directly
related to the placement of the reference points and the radio map used to compute the device location. Traditionally, deploying
the reference points and building the radio map require human intervention and are extremely time-consuming. In this paper
we present an approach to reduce the manual calibration efforts needed to deploy an RSS-based localization system, both when
using only one RF technology or when using a combination of RF technologies. It is an automatic approach both to build a radio
map in a given workspace by means of a signal propagation model, and to assess the system calibration that best fits the required
accuracy by using a multi-objective genetic algorithm. 相似文献
139.
Paolo Bettini Alessandro Airoldi Giuseppe Sala Luca Di Landro Massimo Ruzzene Alessandro Spadoni 《Composites Part B》2010,41(2):133-147
This paper investigates complex composite cellular structures featuring a chiral topology with the ability to undergo large overall displacements with limited straining of its components. Numerical analyses are performed to exploit such properties in the design of a morphing airfoil. The advantages associated with the use of composites are investigated by comparing the numerical results with those obtained with a metallic structure. A manufacturing process is then developed to assemble the considered structural configurations using composite materials. The novel process developed is described as applied to the manufacturing of macro chiral components that are tested to evaluate their ability to undergo large deformations. Finally, detailed numerical models of the manufactured structures are presented as a possible approach to evaluate the strength of the proposed configuration. 相似文献
140.
The scope for diffusion of very low-enthalpy geothermal plants in the Piemonte region of Italy, using groundwater heat pumps (GWHP), was analyzed to check environmental sustainability and the benefits in terms of reducing greenhouse gas emissions from fossil fuels. GWHP implementation seemed particularly suitable to the specific characteristics of the Piemonte plain. An important thick and productive shallow aquifer is present across the entire plain beneath the major energy users and is therefore appropriate for geothermal energy development purposes. The building stock could be adapted to heat pumps in different ways, but objective-oriented policies will be required to reach the best results in terms of environmental benefits. 相似文献