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81.
We report on the combined magnetization and electron paramagnetic resonance characterization of a novel Ti‐O organic–inorganic gel hybrid and the related electron–hole generation process upon UV illumination. We find that electrons are injected into the conduction band of the Ti‐O framework, photoreducing TiIV to TiIII. TiIII sites are mainly located on the surface, owing to the nanometric dimensions of the inorganic component. Surprisingly, the symmetry of the TiO6 octahedra depends on the level of illumination: in the lightly UV‐exposed samples TiIII is sited in the weakly distorted TiO6 octahedra to which methanoate groups are bonded, as suggested by electron spin echo envelope modulation (ESEEM) experiments. Extensive illumination causes structural rearrangements, leading to enhanced tetragonal TiO6 distortion and shifting the TiIII interaction towards the hydroxide groups or water. The results provide clear evidence for an interfacial charge transfer between the quantum‐size TiO lattice and coordinated species upon in situ and ex situ UV illumination at temperatures from room temperature to 5 K.  相似文献   
82.
ABSTRACT

The field of Artificial General Intelligence needs a simple and understandable measure of progress to aid in passing the difficult Turing Test. The proposed Ladder Metric introduces a sequence of levels that intelligent agents must climb in order to reach the final, Turing indistinguishable, level. Just like the Turing test, the levels can only be defined in terms of general properties and behaviour rather than specific operational requirements. To track the progress and make comparisons one must climb and determine the achieved rung of the proposed ladder.  相似文献   
83.
In order to assess the present situation of schistosomiasis in the Zona da Mata Sul, Pernambuco State, Brazil, a study was conducted in the following phases: origin, historical and temporal evolution, and basic determinants of this health/disease process; critical assessment of comprehensive intervention programs implemented by the State in the region since 1970; and a case study in 17 counties, representing 1,424 communities and 485,200 inhabitants, and Brazil's second most endemic region based on prevalence rates for schistosomiasis. Temporal series over a 14-year period were used to analyze results of intervention programs. Conclusions were: a) current positivity rates are higher than those observed in the early 1980s; b) the programs' strategy focused almost exclusively on mass treatment, thus allowing for reinfestation and occurrence of new cases; c) proposals such as the PCDEN (Program for Control of Endemic Diseases in the Northeast) aimed at decentralization to the municipal level in the 1990s were not effectively implemented, helping to leave this persistent endemic out of control.  相似文献   
84.
Metabolomics encompasses the study of small molecules in a biological sample. Liquid Chromatography coupled with Mass Spectrometry (LC-MS) profiling is an important approach for the identification and quantification of metabolites from complex biological samples. The amount and complexity of data produced in an LC-MS profiling experiment demand automatic tools for the preprocessing, analysis, and extraction of useful biological information. Data preprocessing—a topic that covers noise filtering, peak detection, deisotoping, alignment, identification, and normalization—is thus an active area of metabolomics research. Recent years have witnessed development of many software for data preprocessing, and still there is a need for further improvement of the data preprocessing pipeline. This review presents an overview of selected software tools for preprocessing LC-MS based metabolomics data and tries to provide future directions.  相似文献   
85.
Data processing and identification of unknown compounds in comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GC×GC/TOFMS) analysis is a major challenge, particularly when large sample sets are analyzed. Herein, we present a method for efficient treatment of large data sets produced by GC×GC/TOFMS implemented as a freely available open source software package, Guineu. To handle large data sets and to efficiently utilize all the features available in the vendor software (baseline correction, mass spectral deconvolution, peak picking, integration, library search, and signal-to-noise filtering), data preprocessed by instrument software are used as a starting point for further processing. Our software affords alignment of the data, normalization, data filtering, and utilization of retention indexes in the verification of identification as well as a novel tool for automated group-type identification of the compounds. Herein, different features of the software are studied in detail and the performance of the system is verified by the analysis of a large set of standard samples as well as of a large set of authentic biological samples, including the control samples. The quantitative features of our GC×GC/TOFMS methodology are also studied to further demonstrate the method performance and the experimental results confirm the reliability of the developed procedure. The methodology has already been successfully used for the analysis of several thousand samples in the field of metabolomics.  相似文献   
86.
Electroporation-based applications require the use of specific pulse parameters for a successful outcome. When recommended values of pulse parameters cannot be set, similar outcomes can be obtained by using equivalent pulse parameters. We determined the relations between the amplitude and duration/number of pulses resulting in the same fraction of electroporated cells. Pulse duration was varied from 150 ns to 100 ms, and the number of pulses from 1 to 128. Fura 2-AM was used to determine electroporation of cells to Ca(2+). With longer pulses or higher number of pulses, lower amplitudes are needed for the same fraction of electroporated cells. The expression derived from the model of electroporation could describe the measured data on the whole interval of pulse durations. In a narrower range (0.1-100 ms), less complex, logarithmic or power functions could be used instead. The relation between amplitude and number of pulses could best be described with a power function or an exponential function. We show that relatively simple two-parameter power or logarithmic functions are useful when equivalent pulse parameters for electroporation are sought. Such mathematical relations between pulse parameters can be important in planning of electroporation-based treatments, such as electrochemotherapy and nonthermal irreversible electroporation.  相似文献   
87.
Web-based solutions and interfaces should be easy, more intuitive, and should also adapt to the natural and cognitive information processing and presentation capabilities of humans. Today, human-controlled multimodal systems with multimodal interfaces are possible. They allow for a more natural and more advanced exchange of information between man and machine. The fusion of web-based solutions with natural modalities is therefore an effective solution for users who would like to access services and web content in a more natural way. This article presents a novel multimodal web platform (MWP) that enables flexible migration from traditionally closed and purpose-oriented multimodal systems to the wider scope offered by web applications. The MWP helps to overcome problems of interoperability, compatibility, and integration that usually accompany migrations from standard (task-oriented) applications to web-based solutions and multiservice networks, thus enabling the enrichment of general web-based user interfaces with several advanced natural modalities in order to communicate and exchange information. The MWP is a system in which all modules are embedded within generic network-based architecture. When using it, the fusion of user front ends with new modalities requires as little intervention to the code of the web application as possible. The fusion is implemented within user front ends and retains the web-application code and its functionalities intact.  相似文献   
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The point-in-polygon problem is often encountered in geographical information systems. The algorithms usually work on polygons defined by straight edges. In some situations, however, polygons containing circular arcs are applied. In geographical information systems these polygons are usually considered as geometric buffers, geodesic offsets, or geodesic parallels. This paper presents three algorithms suitable for providing information about the containment of a point in geometric buffers: the Ray-crossing method, the Cell-Based Algorithm and the Approximate approach. An extensive experimental section allows the reader to select the most efficient algorithm for practical problems.  相似文献   
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