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51.
This article delineates the design and synthesis of a novel, bio-functionalized, magneto-fluorescent multifunctional nanoparticles suitable for cancer-specific targeting, detection and imaging. Biocompatible, hydrophilic, magneto-fluorescent nanoparticles with surface-pendant amine, carboxyl and aldehyde groups were designed using o-carboxymethyl chitosan (OCMC). The free amine groups of OCMC stabilized magnetite nanoparticles on the surface allow for the covalent attachment of a fluorescent dye such as rhodamine isothiocyanate (RITC) with the aim to develop a magneto-fluorescent nanoprobe for optical imaging. In order to impart specific cancer cell targeting properties, folic acid and its aminated derivative was conjugated onto these magneto-fluorescent nanoparticles using different pendant groups (-NH(2), -COOH, -CHO). These newly synthesized iron-oxide folate nanoconjugates (FA-RITC-OCMC-SPIONs) showed excellent dispersibility, biocompatibility and good hydrodynamic sizes under physiological conditions which were extensively studied by a variety of complementary techniques. The cellular internalization efficacy of these folate-targeted and its non-targeted counterparts were studied using a folate-overexpressed (HeLa) and a normal (L929 fibroblast) cells by fluorescence microscopy and magnetically activated cell sorting (MACS). Cell-uptake behaviors of nanoparticles clearly demonstrate that cancer cells over-expressing the human folate receptor internalized a higher level of these nanoparticle-folate conjugates than normal cells. These folate targeted nanoparticles possess specific magnetic properties in the presence of an external magnetic field and the potential of these nanoconjugates as T(2)-weighted negative contrast MR imaging agent were evaluated in folate-overexpressed HeLa and normal L929 fibroblast cells.  相似文献   
52.
This paper investigates under what conditions stress from the use of SNS is linked to addiction to the use of the same SNS. Integrating three theoretical strands—the concept of feature‐rich Information Technology (IT), the theory of technology frames, and distraction as a coping behaviour—we theorize two types of coping behaviours in response to stressors experienced from the use of SNS. These are ‐ distraction through use of the same SNS and distraction through activities outside the use of the SNS. We hypothesize relationships between stressors from SNS use, the two coping behaviours and SNS addiction. We further articulate the role of SNS use habit. We test the hypotheses through a three‐wave survey of 444 Facebook users with data collected at three different points in time. The paper's contributions are to theorize and empirically validate the psychological concept of distraction as a coping behaviour in response to stress from the use of SNS and, in doing so, explain why there may be a link between technostress from and technology addiction to the use of the same SNS.  相似文献   
53.
54.
Preface     
Microsystem Technologies -  相似文献   
55.
In this study, a particle swarm optimization method is employed to find the optimal operating parameters and geometrical parameters, which maximize the coefficient of performance (COP) of an inertance pulse tube refrigerator (IPTR). The considered decision variables of the IPTR are the charging pressure, which varies from 15 to 25 bar, operating frequency varying from 20 to 60 Hz, geometrical parameters, such as diameter varying from 15.0 to 25.00 mm, and length varying from 40.0 to 70 mm of the regenerator; diameter varying from 12.0 to 20.00 mm and length varying from 40.0 to 80 mm of the pulse tube; and diameter varying from 2.0 to 6.00 mm and length varying from 1.0 to 3.0 m of the inertance tube. A 1D numerical model, based on the finite volume discretization of governing equations has been selected to build the initial design matrix and solve the governing continuity, momentum, and energy equations. Analysis of variance is performed using the result obtained from the numerical simulation to visualize the variations of COP as a combination of various input parameters. It is observed that after optimizing the input parameters, the COP of the IPTR increases by 15.14%.  相似文献   
56.
In this paper, we consider the effect of BDD-based under-approximation on a hybrid approach using BDDs and SAT-BMC for error detection on a computing grid. We experimentally study effect of under-approximation approaches on a non-traditional parallelization of BMC based on state space partitioning. This parallelization is accomplished by executing multiple instances of BMC independently from different seed states, that are selected from the reachable states in different partitions. Such states are spread out across the state space and can potentially be deep. Since all processors work independently of each other, this scheme is suitable for bug hunting using a grid-like network. Our experimental results demonstrate improvement over existing approaches, and we show that the method can effectively utilize a large grid network.  相似文献   
57.
The Journal of Supercomputing - Real-time service has become a key for efficient serving of the Internet of Things (IoT)-based smart e-Healthcare. Several orientations have tried to pave this side...  相似文献   
58.

Graphene has been conjugated with Silicene which is a 2D nanosheet of silicon crystal to analyze myriad physico-chemical properties. Upon intercalation of silicene between two graphene nanosheets, there has been a significant shift in the energy of electronic configuration at different isovalues from − 0.12 to + 0.12. Similarly, by analyzing the electronic energy states of silicene–graphene–silicene, a range of isovalues from − 0.08 to + 0.08 were observed. I–V curve exhibited a linear response for graphene–silicene–graphene sandwiched structure and a semiconducting like behavior for silicene–graphene–silicene structure. Band gap measurement in case of graphene–silicene–graphene system is reported to be ~ 0.18 eV, which is a narrow region. While in case of silicene–graphene–silicene, a band gap value of ~ 1.01 eV is calculated that appears to be a pretty broad region. Transmission spectrum also shows intensity in peaks for Gr–Si–Gr case as compared to Si–Gr–Si combinations. Silicon is widely perceived to exhibit outstanding semiconducting behavior and has already been used in devising various electronic devices. In this present work, we try to analyze the outcome of the silicene and graphene at the nanometer scale in various combinations in a bid to understand the potential interaction mechanism between the two nanosheets which would help in the fabrication of the silicene–graphene based optoelectronic devices.

  相似文献   
59.
We investigate the effect of conditions that create technostress, on technology‐enabled innovation, technology‐enabled performance and overall performance. We further look at the role of technology self‐efficacy, organizational mechanisms that inhibit technostress and technology competence as possible mitigations to the effects of technostress creators. Our findings show a negative association between technostress creators and performance. We find that, while traditional effort‐based mechanisms such as building technology competence reduce the impact of technostress creators on technology‐enabled innovation and performance, more empowering mechanisms such as developing technology self‐efficacy and information systems (IS) literacy enhancement and involvement in IS initiatives are required to counter the decrease in overall performance because of technostress creators. Noting that the professional sales context offers increasingly high expectations for technology‐enabled performance in an inherently interpersonal‐oriented and relationship‐oriented environment with regard to overall performance, and high failure rates for IS acceptance/use, the study uses survey data collected from 237 institutional sales professionals.  相似文献   
60.
Quantum Information Processing - A general quantum network for implementing non-local control-unitary gates, between remote parties at minimal entanglement cost, is shown to be a rooted-tree...  相似文献   
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