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71.
Software and Systems Modeling - The Internet of things has been adopted in several sectors both influencing how people work and enhancing organizations’ business processes. This resulted in...  相似文献   
72.
In order to consider the response of concrete columns confined by FRP and FRCM system, proper models have to be formulated. In this context the present paper shows a generalized criterion for the determination of the increase in strength, in ductility and in dissipated energy for varying corner radius ratio of the cross section and fiber volumetric ratio. The procedure is based on the best fitting of several experimental data and unlike the usual empirical approaches available in the literature, the proposed technique relates the confinement effectiveness to a single parameter representative of the relative stiffness between the original concrete core and the reinforcement system. Furthermore, the proposed analytical models overcomes the limit of many empirical or semi-empirical models given in the literature that are applicable only to specific cases. A comparison with same available models confirm the reliability of the proposed procedure.  相似文献   
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Research dealing with early diagnosis and efficient treatment in colon cancer to improve patient''s survival is still under investigation. Chemotherapeutic agent result in high systemic toxicity due to their non‐specific actions on DNA repair and/or cell replication. Traditional medicine such as Lycopodium clavatum (LC) has been claimed to have therapeutic potentials against cancer. The present study focuses on targeted drug delivery of cationic liposomal nanoformulated LC (CL‐LC) in colon cancer cells (HCT15) and comparing the efficacy with an anti‐colon cancer drug, 7‐ethyl‐10‐hydroxy‐camptothecin (SN38) along with its nanoformulated form (CL‐SN38). The colloidal suspension of LC was made using thin film hydration method. The drugs were characterised using ultraviolet, dynamic light scattering, scanning electron microscopy, energy, dispersive X‐ray spectroscopy. In vitro drug release showed kinetics of 49 and 89% of SN38 and LC, whereas CL‐SN38 and CL‐LC showed 73 and 74% of sustained drug release, respectively. Studies on morphological changes, cell viability, cytotoxicity, apoptosis, cancer‐associated gene expression analysis of Bcl‐2, Bax, p53 by real‐time polymerase chain reaction and western blot analysis of Bad and p53 protein were performed. Nanoformulated LC significantly inhibited growth and increased the apoptosis of colon cancer cells indicating its potential anti‐cancer activity against colon cancer cells.Inspec keywords: cancer, biological organs, cellular biophysics, drug delivery systems, drugs, nanomedicine, genetics, DNA, molecular biophysics, biochemistry, lipid bilayers, toxicology, suspensions, colloids, light scattering, X‐ray chemical analysis, solvation, enzymes, nanostructured materialsOther keywords: energy dispersive X‐ray spectroscopy, in vitro drug release, morphological changes, cell viability, cytotoxicity, apoptosis, cancer‐associated gene expression analysis, Bcl‐2, Bax, real‐time polymerase chain reaction, western blot analysis, Bad protein, p53 protein, scanning electron microscopy, dynamic light scattering, ultraviolet scattering, thin film hydration method, colloidal suspension, nanoformulated form CL‐SN38, 7‐ethyl‐10‐hydroxy‐camptothecin, anticolon cancer drug, colon cancer cells HCT15, cationic liposomal nanoformulated LC, targeted drug delivery, therapeutic potentials, Lycopodium clavatum, traditional medicines, cell replication, DNA repair, nonspecific actions, high systemic toxicity, chemotherapeutic agents, patient survival, colon cancer treatment, colon cancer diagnosis, CL‐LC, potential anticancer activity  相似文献   
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Formation of densely packed thin films of semiconductor nanocrystals is advantageous for the exploitation of their unique optoelectronic properties for real-world applications. Here we investigate the fundamental role of the structure of the bridging ligand on the optoelectronic properties of the resulting hybrid film. In particular, we considered hybrid films formed using the same CdSe nanocrystals and two organic ligands that have the same bidentate dithiocarbamate binding moiety, but differ in their bridging structures, one bridged by ethylene, the other by phenylene that exhibits conjugation. Based on the results of photo-excited carrier dynamics experiments combined with theoretical calculations on the electronic states of bridged CdSe layers, we show that only the phenylene-based ligand presents a strong hybridization of the molecular HOMO state with CdSe layers, that is a marker of formation of an effective bridge. We argue that this hybridization spread favors the hopping of photo-excited carriers between nanocrystals, which may explain the reported larger photo-currents in phenylene-based hybrid films than those observed in ethylene-based ones.
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Nano Research - The engineering of self-organized plasmonic metasurfaces is demonstrated using a maskless technique with defocused ion-beam sputtering and kinetically controlled deposition. The...  相似文献   
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Third generation of mobile systems is now entering the operational phase; European Community ACTS (RACE follow-on) programme just aims at finalizing the plenty of solutions resulting from the European Community RACE programme as well as from several other studies and researches. European manufactures, also deeply involved in the ACTS programme, seem to show a preference for solutions which gradually upgrade the present pan-European GSM successful standard. The underlying concept is the one of asmooth migration from the GSM network to the third generation system, in order to reuse, at least in the first phases of the transition, most of the existing technologies and infrastructures already implemented for the GSM network. In this respect, this paper, by referring to radio interface aspects, proposes a two step evolution: in the first step, a Dynamic Channel Allocation (DCA) strategy with distributed control should be implemented for coping with the high variance of traffic entailed by the reduction of cell dimensions; in the second step, a gradual upgrading of the GSM Base Stations should allow a smooth transition towards the third generation Packet Reservation Multiple Access (PRMA) technique and the provision of broadband services. The paper is partly based upon the work performed by the author in the framework of the RACE project Satellite Integration in the Future Mobile Network (SAINT) and of the European Community ACTS Projects MEDIAN. The opinions herewith reported are not necessarily those of the European Community.  相似文献   
80.
Calculations are presented, based on a Density Functional approach, of the first excited states (l=1) of alkali metal atoms (Cs and Na) in liquid 4He. We find large departures from the spherical bubble in the liquid4He structure when the alkali atom is excited. The shifts from the free atom values of the excitation and emission transition lines are calculated and compared with the experimental results. According to our calculations, the so far unseen radiative deexcitation transition for light alkalis in4He may lie in an unexplored infrared region of the spectrum.  相似文献   
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