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91.
Multimedia Tools and Applications - The detection of near duplicate images in large databases, such as the ones of popular social networks, digital investigation archives, and surveillance systems,...  相似文献   
92.
Lung cancer represents the leading cause of cancer-related mortality throughout the world. Patients die of local progression, disseminated disease, or both. At least one third of the people with lung cancer develop brain metastases at some point during their disease, even often before the diagnosis of lung cancer is made. The high rate of brain metastasis makes lung cancer the most common type of tumor to spread to the brain. It is critical to understand the biologic basis of brain metastases to develop novel diagnostic and therapeutic approaches. This review will focus on the emerging data supporting the involvement of the chemokine CXCL12 and its receptor CXCR4 in the brain metastatic evolution of non-small-cell lung cancer (NSCLC) and the pharmacological tools that may be used to interfere with this signaling axis.  相似文献   
93.
The possibility of selectively delivering metal complexes to a defined cohort of cells on the basis of their metabolic features is a highly challenging goal, which may be extremely useful for a series of purposes, including diagnosis and therapy of pathological states, such as cancer. Tumor cells display augmented requests for carbohydrates and, in particular, for glucose in order to sustain their high proliferation rate, which causes an increased glycolytic process (Warburg effect). Since several metal complexes display diagnostic and/or therapeutic properties, their conjugation to carbohydrate portions often induce their preferential accumulation in cancer cells, similarly to what is observed with fluorodeoxyglucose (FDG). In this review we have considered the latest developments of glycoconjugates containing metal complexes in their structures. These compounds are classified as diagnostic or therapeutic agents and are further systematically discussed on the basis of the metal atom they contain. Several diagnostic techniques are possible with these probes, since, depending on the metal species included in their structures, they may be employed in nuclear medicine (PET, SPECT), magnetic resonance imaging, luminescence and phosphorescence. At the same time, the lack of selective cytotoxicity displayed by several metal-based chemotherapeutic agents, may also be solved by the conjugation of these agents to carbohydrate portions. Overall, data so far available reveal the great potential of this chemical class in the early detection and in the cure of severe neoplastic diseases, which still needs to be fully explored in the clinic.  相似文献   
94.
Traditionally, direct marketing companies have relied on pre-testing to select the best offers to send to their audiences. Companies systematically dispatch the offers under consideration to a limited sample of potential buyers, rank them with respect to their performance and, based on this ranking, decide which offers to send to the wider population. Though this pre-testing process is simple and widely used, recently the direct marketing industry has been under increased pressure to further optimize learning, in particular when facing severe time and space constraints. Taking into account the multimedia nature of offers, which typically comprise both a visual and text component, we propose a two-phase learning strategy based on a cascade of regression methods. This proposed approach takes advantage of visual and text features to improve and accelerate the learning process. Experiments in the domain of a commercial multimedia messaging service show the effectiveness of the proposed methods that improve on classical learning techniques. The main contribution of the present work is to demonstrate that direct marketing firms can exploit the information on visual content to optimize the learning phase. The proposed methods can be used in any multimedia direct marketing domains in which offers are composed by image and text.  相似文献   
95.
Dough formation process is a relevant step in cereal goods manufacturing, as in this stage the material develops its mechanical properties. Dough structure formation is promoted by mechanical energy transfer from the mixer blades to the sample, affecting flour hydration and gluten network formation kinetics. This paper reports a model of dough formation process during a farinograph test, accounting for all relevant physical phenomena: wheat particles hydration, gluten network formation, evolution and (eventually) disruption as effect of mixing energy. Results of the model are in terms of network strength and connectivity evolution, and a qualitative agreement was found with typical farinograph results. This allowed to employ the model to study the effect of the flour's physical properties on the empirically defined (but employed as industrial standards) farinograph outputs. Therefore, simulation results allowed to gain a physical insight of the technological parameters from a farinograph test.  相似文献   
96.

Many people are currently working in call centres and much more are expected to work in them in the near future. Call centres are, in a sense, 'modern factories' where services are delivered through information and communication technologies. The human activity within the dynamic and articulated reality of such work settings offers new challenges for cognitive ergonomics. Indeed, work in call centres has to be conceptualized in terms of distributed knowledge. This means that only part of the knowledge needed to carry out any transaction is (or rather has to be) in the mind of the operator; relevant knowledge may be distributed among colleagues in the organization, available and accessible cognitive artefacts in the work environment, and clients. This paper discusses the potential contribution that human factors and cognitive ergonomics can provide in tackling the new and old problems that emerge in organizations where knowledge is an asset.  相似文献   
97.
This article addresses the problem of thermal stresses for isotropic microstretch elastic cylinders subjected to a temperature distribution that is linear in the axial coordinate. A direct method is used to reduce the problem to solving plane strain problems. The results are used to study the deformation of circular cylinders.  相似文献   
98.
The growth of many breast tumors is stimulated by estradiol (E2), which activates a classic mechanism of regulation of gene expression and signal transduction pathways inducing cell proliferation. Polyphenols of natural origin with chemical similarity to estrogen have been shown to interfere with tumor cell proliferation. The aim of this study was to investigate whether hydroxytyrosol (HT) and oleuropein (OL), two polyphenols contained in extra‐virgin olive oil, can affect breast cancer cell proliferation interfering with E2‐induced molecular mechanisms. Both HT and OL inhibited proliferation of MCF‐7 breast cancer cells. Luciferase gene reporter experiments, using a construct containing estrogen responsive elements able to bind estrogen receptor alpha (ERα) and the study of the effects of HT or OL on ERα expression, demonstrated that HT and OL are not involved in ERα‐mediated regulation of gene expression. However, further experiments pointed out that both OL and HT determined a clear inhibition of E2‐dependent activation of extracellular regulated kinase1/2 belonging to the mitogen activating protein kinase family. Our study demonstrated that HT and OL can have a chemo‐preventive role in breast cancer cell proliferation through the inhibition of estrogen‐dependent rapid signals involved in uncontrolled tumor cell growth.  相似文献   
99.
A novel preparative-scale triple gas chromatographic system, equipped with three Deans-switch devices, is herein described. The isolation of volatile compounds was achieved by using a lab-made collection system. Considerations are made on the possibility to inject high volumes of neat sample, maintaining, at the same time, high resolution levels. The degree of recovery of a series of compounds, characterized by a differing volatility, is also reported. In this respect, different collection conditions were evaluated, namely, the presence (or not) of packing material as well as CO(2) cooling, in various combinations. Finally, the interconnected features, that is time requirements and the isolation of "acceptable" analyte quantities (e.g., milligram level for NMR characterization), are related to parameters such as analyte concentration, injected volume, collection conditions, and number of GC runs. The results herein reported will demonstrate the need for a high-resolution GC step, prior to analyte collection, in the prep-GC analysis of complex samples.  相似文献   
100.
Three different bias strategies aimed to reduce the effect of tuning on either the differential input range or the common-mode range of triode-region CMOS transconductors are presented. The method is applied to an original transconductor topology that is optimized to produce ultralow Gm values. A prototype circuit, which was designed with the 0.35-mum bipolar-CMOS-DMOS (BCD6) process of STMicroelectronics, is presented. The effectiveness and limitations of the method are characterized by means of electrical simulations  相似文献   
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