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71.
Remote controls are especially problematic for writing text, something necessary in many interactive digital TV applications (IDTV). In the context of research aimed at finding effective entry methods for IDTV applications, an empirical investigation was carried out and is presented in this article. The study analyzed the errors committed by 82 users in an experiment in which they wrote 7,395 sentences. Several typing methods suitable for IDTV contexts were used for experimentation. There were 3,562 of the sentences that registered at least one error. These errors were classified and their main causes analyzed, the particular characteristics of the users taken into account. The results show that the most frequent errors are proximity mistakes in all the evaluated methods. They appear in between 13.75% and 32.31% of the sentences, depending on the input method. Also, age and background are major aspects affecting the number and type of mistakes. The results could be the basis of changes in the design of conventional remote controls or in the design of advanced techniques for error recognition and correction.  相似文献   
72.
We describe the voltammetric measurement of the full oxidation of adsorbed CO on unsupported platinum electrocatalysts, with concomitant cyclic voltammetry of the hydrogen adsorption and desorption. The hydrogen region of platinum is used to parse the platinum surface into sites associated with weakly bound (WB) hydrogen and strongly bound (SB) hydrogen. By monitoring changes in the hydrogen region while following the two observed CO oxidation peaks, we are able to identify the WB sites as being the most active sites for COads electro-oxidation. The full oxidation peak is fitted to a model based on a modified Butler-Volmer equation that includes the two families of sites. Excellent agreement with experimental results is obtained, and the resulting fits yield the kinetic parameters for the two families of sites. When combined with coulometry, these kinetic analyses also show the importance of linear- and bridged-COads species in the electro-oxidation process. Limitations of the model and the role of COads dynamics amongst the various surface sites are discussed.  相似文献   
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74.
Cognitive-behavioral psychotherapies (CBT) are among the first-line interventions for major depressive disorder (MDD), and a significant number of studies indicate their efficacy in the treatment of this disorder. However, differential effects of various forms of CBT have seldom been analyzed in the same experimental design. On the basis of data collected in a randomized clinical trial comparing the efficacy of rational-emotive behavior therapy (REBT), cognitive therapy (CT), and pharmacotherapy (SSRI) in the treatment of MDD, the present article investigates the theory of change advanced by REBT and CT. Measures included to test the two theories of change assess three classes of cognitions: (a) automatic thoughts, (b) dysfunctional attitudes, and (c) irrational beliefs. The results indicate that REBT and CT (and also pharmacotherapy) indiscriminately affect the three classes of cognitions. On the long term (follow-up), a change in implicit demandingness seems more strongly associated with reduced depression and relapse prevention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
MgH2 nanocomposites with ZrCrNi alloy obtained by high energy ball-milling were studied as-milled and after several hydriding-deydriding cycles. The microstructure and morphology of the samples was characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD patterns show that no phase formation between MgH2 and elements of the alloys takes place during milling and after cycling. Different morphology of the powders as-milled and after cycling was observed by SEM. Pressure-composition isotherms of these composites were obtained in the pressure and temperature range of 0.1–15 bar and 200–300 °C respectively. The maximum reversible storage capacity was found to be 6.2 wt% at 300 °C. Absorption/desorption kinetics data at pressures of 0.1–5.0 bar and temperatures of 275 °C and 300 °C show that an activation process of about 20 cycles at 300 °C is necessary for stabilization of the kinetics and for achievement of the full hydrogen capacity. The thermodynamic parameters, i.e. enthalpy of formation and dissociation calculated using Van't Hoff plots, were found to be 73.53 kJ mol?1 and 87.63 kJ mol?1 respectively, in agreement with MgH2 data reported in literature.  相似文献   
76.
Resistance to Immune Checkpoint Blockade (ICB) constitutes the current limiting factor for the optimal implementation of this novel therapy, which otherwise demonstrates durable responses with acceptable toxicity scores. This limitation is exacerbated by a lack of robust biomarkers. In this study, we have dissected the basal TME composition at the gene expression and cellular levels that predict response to Nivolumab and prognosis. BCR, TCR and HLA profiling were employed for further characterization of the molecular variables associated with response. The findings were validated using a single-cell RNA-seq data of metastatic melanoma patients treated with ICB, and by multispectral immunofluorescence. Finally, machine learning was employed to construct a prediction algorithm that was validated across eight metastatic melanoma cohorts treated with ICB. Using this strategy, we have unmasked a major role played by basal intratumoral Plasma cells expressing high levels of IGKC in efficacy. IGKC, differentially expressed in good responders, was also identified within the Top response-related BCR clonotypes, together with IGK variants. These results were validated at gene, cellular and protein levels; CD138+ Plasma-like and Plasma cells were more abundant in good responders and correlated with the same RNA-seq-defined fraction. Finally, we generated a 15-gene prediction model that outperformed the current reference score in eight ICB-treated metastatic melanoma cohorts. The evidenced major contribution of basal intratumoral IGKC and Plasma cells in good response and outcome in ICB in metastatic melanoma is a groundbreaking finding in the field beyond the role of T lymphocytes.  相似文献   
77.
Culture-dependent and -independent approaches were applied to identify the bacterial species involved in Italian table olive fermentation. Bacterial identification showed that Lactobacillus pentosus was the dominant species although the presence of Lactobacillus plantarum, Lactobacillus casei, Enterococcus durans, Lactobacillus fermentum and Lactobacillus helveticus was observed. Rep-PCR allowed to obtain strain-specific profiles and to establish a correlation with table olive environment. PCR-DGGE (Denaturing Gradient Gel Electrophoresis) confirmed the heterogeneity of bacterial community structure in fermented table olives as well as the prevalence of L. pentosus. The strains were characterized on the basis of technological properties (NaCl tolerance, β-glucosidase activity and the ability to grow in synthetic brine and in presence of 1 g/100 mL oleuropein). L. pentosus showed a high capacity of adaptation to the different conditions characterizing the olive ecosystem. This species showed the highest percentage of strains able to grow in presence of 10 g/100 mL NaCl, oleuropein and in the synthetic brine. Moreover, all the strains belonging to L. pentosus and L. plantarum species showed a β-glucosidase activity. This study allowed both to identify the main species and strains associated to Italian table olives and to obtain a lactic acid bacteria collection to apply as starter culture in the process of olive fermentation.  相似文献   
78.
Achieving a shared understanding of requirements is difficult in any situation, even more so in global software development projects. In such environments, people must deal not only with the lack of face to face communication, but also with other issues such as time difference, cultural diversity and a large amount of information originating from different sources throughout the world. Obtaining the right requirements therefore implies extra effort. In order to minimize such problems, we propose a framework that focuses on analyzing the factors that may be problematic in global software development and which suggests a set of strategies to improve the requirements elicitation process in such environments. In this paper, we describe the different phases of our framework and present the results of an experiment that test part of this framework. The results indicate that applying some of the strategies proposed in the framework seems to positively affect the stakeholders’ satisfaction with regard to communication. Moreover, the quality of the written software requirements specifications seems to be better as well when using those strategies.  相似文献   
79.
80.
The major part of the production costs of pharmaceuticals can be imputed to the downstream processing, where membrane technologies have to deal with some challenges as separations involving solutes with similar sizes or solvent recovery and recycling. This work contributes to the progress in the design of continuous organic solvent nanofiltration systems for this purpose and includes the configuration of dual membrane cascades, sensitivity analysis of the operation variables, and economic optimization as innovations. Analyzed configurations include multistage cascades up to three stages, and dual membrane cascades up to five stages. The total costs (TC) were chosen as the formulated objective function to minimize in the economic optimization strategy. The treatment of the residual stream leaving the system resulted the main cost of the process (more than 85% for dual cascades), but the solvent recovery units can significantly reduce the TC (64–77% depending on the required solvent quality). © 2014 American Institute of Chemical Engineers AIChE J, 60: 931–948, 2014  相似文献   
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