crossmodal error correction of continuous handwriting recognition by speech

In recognition-based user interface, users’ satisfaction is determined not only by recognition accuracy but also by effort to correct recognition errors. In this paper, we introduce a crossmodal error correction technique, which allows users to correct errors of Chinese handwriting recognition by speech. The focus of the paper is a multimodal fusion algorithm supporting the crossmodal error correction. By fusing handwriting and speech recognition, the algorithm can correct errors in both character extraction and recognition of handwriting. The experimental result indicates that the algorithm is effective and efficient. Moreover, the evaluation also shows the correction technique can help users to correct errors in handwriting recognition more efficiently than the other two error correction techniques.

桌面虚拟现实环境下的双手交互技术

面向桌面虚拟环境,在分析通用交互设备特点的基础上,提出了具有广泛适用性的双手交互的设备组合;根据虚拟现实通用交互任务的需求,结合设备特点,提出了为左、右手设备分配不同的子任务的策略;组合不同的单手交互技术,提出了包括基于辅助平面的双手交互等3个适用于典型桌面设备组合的双手交互技术;开发了双手交互技术工具箱,并进行了应用验证·

非洲爪蟾Brunol和MCPH基因在早期胚胎发育过程中表达的研究及随机定向酵母双杂交cDNA文库的构建

BRUNOL/CELF家族RNA结合蛋白在转录后调控（post-transcriptional regulation）中起着至关重要的作用，参与多种组织的发育过程。本研究中，我们描述了非洲爪蟾5个Brunol 基因的克隆与表达。其中只有Brunol2是母源性以及合子表达的，其它的4个Brunol基因都是合子表达的，但起始表达的发育时期有所不同。爪蟾发育过程中，Brunol1、4和5基因特异性地在神经系统中表达，包括脑、脊髓、眼泡和耳泡。Brunol2和3基因在体节中胚层与神经系统表达。Brunol2也在晶状体中有非常高的表达。在转染的Hela细胞中，BRUNOL1、2和3蛋白定位于细胞质和细胞核中，BRUNOL4和5只是定位于细胞质中，显示它们具有不同的功能。 人的microcephalin1（MCPH1）基因的遗传突变产生原发性小头症，而在人类的进化过程中，这个基因的变化可能对人脑体积的增加和认知能力的增强也起到重要的作用。但是对于MCPH基因在其它物种中功能的研究才刚刚开始。我们克隆了非洲爪蟾MCPH基因，发现非洲爪蟾具有A，B两个同源基因，其功能域的保守性较高，暗示非洲爪蟾MCPH基因仍然执行一些保守的功能，但MCPHB由于突变只编码一种截短的蛋白，目前尚不清楚它是否是有功能的。胚胎原位杂交的结果显示MCPHA，B基因在胚胎发育中的表达图式相似，但MCPHB的表达水平较低。在神经胚期，二者均表达于头部基板区，在尾芽期主要表达于咽鳃区，而在脑区的表达并不显著，与小鼠中的表达模式不同，提示在爪蟾中MCPH基因可能主要参与咽鳃区而不是脑的发育。 为了进一步筛选这些蛋白可能的结合因子，我们构建了非洲爪蟾双杂交cDNA文库。其中利用修饰的随机引物和特别设计的连接头在合成双链cDNA时，在下游合成一个SalI限制性酶切位点，可以将cDNA定向插入载体。通过对于空克隆率和插入片段长度等一系列参数的分析，表明这个定向cDNA文库的构建是成功的。

Biomolecule-nanoparticle hybrids for electrochemical biosensors

Inorganic nanoparticles (NPs) with attractive electronic, optical, magnetic, thermal and catalytic properties have attracted great interest due to their important applications in physics, chemistry, biology, medicine, materials science and interdisciplinary fields. Biomolecule-NP hybrid systems, which combine recognition and catalytic properties of biomolecules with electronic, optical, magnetic and catalytic properties of NPs, are particularly new materials with synergistic properties originating from the components of the hybrid composites. The biomolecule-NP hybrid system has excellent prospects for interfacing biological recognition events with electronic signal transduction so as to design a new generation of bioelectronic devices with high sensitivity.

Effect of the gamma-form crystal on the thermal fractionation of poly(propylene-co-ethylene)

The effect of the gamma-form crystal on the thermal fractionation of a commercial poly(propylene-co-ethylene) (PPE) has been studied by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) techniques. Two thermal fractionation techniques, stepwise isothermal crystallization (SIC) and successive self-nucleation and annealing (SSA), have been used to characterize the molecular heterogeneity of the PPE. The results indicate that the SSA technique possesses a stronger fractionation ability than that of the SIC technique. The heating scan of the SSA fractionated sample exhibits 12 endothermic peaks, whereas the scan of the SIC fractionated sample only shows eight melting peaks. The WAXD observations of the fractionated PPE samples prove that the content of the gamma-form crystals formed during the thermal treatment of the SIC technique is much higher than that of the SSA treatment. The former is 57.4%, whereas the later is 12.6%. The effect of they-form crystals on thermal fractionation ability is discussed.

Novel prefractionation method can be used in proteomic analysis

For the first time, a novel prefractionation method used in proteomic analysis was developed, which is performed by a novel aqueous two-phase system (NATPS) composed of n-butanol, (NH4)(2)SO4, and water. It can separate proteomic proteins into multigroups by one-step extraction. The phase-separation conditions of n-butanol solutions were studied in the presence of commonly used inorganic salts. The NATPS was subsequently developed. Using human serum albumin, zein, and gamma-globulin as model proteins, the separation effectiveness of the NATPS for protein was studied under affection factors, i.e., pH, n-butanol volume, protein, or salt concentration. The model and actual protein samples were separated by the NATPS and then directly used for gel electrophoresis without separating the target proteins from phase-forming reagents. It revealed that the NATPS could separate proteomic proteins into multigroups by one-step extraction. The NATPS has the advantages of rapidity, simplicity, low cost, biocompability, and high efficiency. It need not separate target proteins from the phase-forming reagents. The NATPS has great significance in separation and extraction of proteomic proteins, as well as in methodology.

Confined crystallization behavior of PEO in silica networks

Poly(ethylene oxide) (PEO) and silica (SiO2) organic-inorganic hybrid materials have been synthesized by sol-gel approach. The crystallization behavior of PEO in silica networks has been investigated by differential scanning calorimeter (DSC) and scanning electron micrograph (SEM). The degree of PEO crystallinity in PEO/SiO2 hybrid networks reduces with the increase of SiO2. PEO is in amorphous state when the concentration of PEO is lower than 50 wt% in the hybrid materials. The melting points of PEO in the networks are lower than that of pure PEG, but the melting point of PEO in the networks almost has the same melting point. WAXD and SEM results show that the crystalline behavior of PEO in PEO/SiO2 hybrid system is sternly confined. (C) 1999 Elsevier Science Ltd. All rights reserved.

Interfacial layer and phase inversion behavior in the blend of polyethersulfone and polycarbonate

A blend of polyethersulfone (PES) and polycarbonate (PC) with a ratio of 40/60 was studied by scanning electron microscopy (SEM), dynamic mechanical analysis, and transmission electron microscopy (TEM). It was found that the PES-PC blend is a partially miscible, two-phase system, and an interfacial layer exists between the phases of PES and PC. Specific interaction resulting from the n-complex between PES and PC provides the driving force for formation of the interfacial layer. In addition, phase inversion behavior was also observed for the 40/60 composition.

SAXS measurements of the interface in polyacrylate and epoxy interpenetrating networks with fractal geometry

The interface thickness in two-component interpenetrating polymer networks (IPN) system based on polyacrylate and epoxy were determined using small-angle X-ray scattering (SAXS) in terms of the theory proposed by Ruland. The thickness was found to be nonexistent for the samples at various compositions and synthesized at variable conditions-temperature and initiator concentration. By viewing the system as a two-phase system with a sharp boundary, the roughness of the interface was described by fractal dimension, D, which slightly varies with composition and synthesis condition. Length scales in which surface fractals are proved to be correct exist for each sample and range from 0.02 to 0.4 Angstrom(-1). The interface in the present IPN system was treated as fractal, which reasonably explained the differences between Pored's law and experimental data, and gained an insight into the interaction between different segments on the interface. (C) 1997 Elsevier Science Ltd.

Genome-wide survey of putative serine/threonine protein kinases in cyanobacteria

Background: Serine/threonine kinases (STKs) have been found in an increasing number of prokaryotes, showing important roles in signal transduction that supplement the well known role of two-component system. Cyanobacteria are photoautotrophic prokaryotes able to grow in a wide range of ecological environments, and their signal transduction systems are important in adaptation to the environment. Sequence information from several cyanobacterial genomes offers a unique opportunity to conduct a comprehensive comparative analysis of this kinase family. In this study, we extracted information regarding Ser/Thr kinases from 21 species of sequenced cyanobacteria and investigated their diversity, conservation, domain structure, and evolution. Results: 286 putative STK homologues were identified. STKs are absent in four Prochlorococcus strains and one marine Synechococcus strain and abundant in filamentous nitrogen-fixing cyanobacteria. Motifs and invariant amino acids typical in eukaryotic STKs were conserved well in these proteins, and six more cyanobacteria- or bacteria-specific conserved residues were found. These STK proteins were classified into three major families according to their domain structures. Fourteen types and a total of 131 additional domains were identified, some of which are reported to participate in the recognition of signals or substrates. Cyanobacterial STKs show rather complicated phylogenetic relationships that correspond poorly with phylogenies based on 16S rRNA and those based on additional domains. Conclusion: The number of STK genes in different cyanobacteria is the result of the genome size, ecophysiology, and physiological properties of the organism. Similar conserved motifs and amino acids indicate that cyanobacterial STKs make use of a similar catalytic mechanism as eukaryotic STKs. Gene gain-and-loss is significant during STK evolution, along with domain shuffling and insertion. This study has established an overall framework of sequence-structure-function interactions for the STK gene family, which may facilitate further studies of the role of STKs in various organisms.

Genome-wide survey of putative serine/threonine protein kinases in cyanobacteria

Background: Serine/threonine kinases (STKs) have been found in an increasing number of prokaryotes, showing important roles in signal transduction that supplement the well known role of two-component system. Cyanobacteria are photoautotrophic prokaryotes able to grow in a wide range of ecological environments, and their signal transduction systems are important in adaptation to the environment. Sequence information from several cyanobacterial genomes offers a unique opportunity to conduct a comprehensive comparative analysis of this kinase family. In this study, we extracted information regarding Ser/Thr kinases from 21 species of sequenced cyanobacteria and investigated their diversity, conservation, domain structure, and evolution. Results: 286 putative STK homologues were identified. STKs are absent in four Prochlorococcus strains and one marine Synechococcus strain and abundant in filamentous nitrogen-fixing cyanobacteria. Motifs and invariant amino acids typical in eukaryotic STKs were conserved well in these proteins, and six more cyanobacteria- or bacteria-specific conserved residues were found. These STK proteins were classified into three major families according to their domain structures. Fourteen types and a total of 131 additional domains were identified, some of which are reported to participate in the recognition of signals or substrates. Cyanobacterial STKs show rather complicated phylogenetic relationships that correspond poorly with phylogenies based on 16S rRNA and those based on additional domains. Conclusion: The number of STK genes in different cyanobacteria is the result of the genome size, ecophysiology, and physiological properties of the organism. Similar conserved motifs and amino acids indicate that cyanobacterial STKs make use of a similar catalytic mechanism as eukaryotic STKs. Gene gain-and-loss is significant during STK evolution, along with domain shuffling and insertion. This study has established an overall framework of sequence-structure-function interactions for the STK gene family, which may facilitate further studies of the role of STKs in various organisms.

松辽盆地南部岩性油藏成藏模式与分布规律

According to the basic geologic conditions, the paper is directed by the modem oil-gas accumulation theory and petroleum system in which typical oil pools are analyzed and the shape of lithologic trap and geologic factors are pointed out. The process during which oil and gas migrate from source rock to lithologic trap is rebuilt, and the accumulation model of oil pool is set up. With the comprehensive application of seismic geologic and log data and paying attention to the method and technology which is used to distinguish lithologic accumulation. Promising structural-lithofacies zones are got and the distribution rule of various lithologic accumulation is concluded. With making use of the biologic mark compound, different reservoirs are compared. As a result, the oil and gas in HeiDimiao come from Nenjiang Group's source rocks; in SaErTu from QingShenkou Group's and Nenjiang Group's, and in PuTaohua. GaoTaizi and FuYang from QingShankou Group's. According to the development and distribution of effective source rock, oil distribution and the comparison in the south of SongLiao basin, the characteristic of basin structure and reservoir distribution is considered, and then the middle-upper reservoir of SongLiao basin south are divided into two petroleum system and a complex petroleum system. Because of the characteristic of migration and accumulation, two petroleum systems can furtherly be divided into 6-7 sub-petroleum systems,20 sub-petroleum systems in all. As a result of the difference of the migration characteristic, accumulation conditions and the place in the petroleum system, the accumulation degree and accumulation model are different. So three accumulation mechanism and six basic accumulation model of lithologic trap are concluded. The distribution of lithologic pools is highly regular oil and gas around the generation sag distribute on favorable structural-lithofacies zones, the type of lithological pool vary regularly from the core of sandstone block to the upper zone. On the basic of regional structure and sedimentary evolution, main factors which control the form of trap are discovered, and it is the critical factor method which is used to discern the lithologic trap. After lots of exploration, 700km~2 potential trap is distinguished and 18391.86 * 10~4 tons geologic reserves is calculated. Oil-water distribution rule of pinch-out oil pool is put up on plane which is the reservoirs can be divided into four sections. This paper presented the law of distribution of oil and water in updip pinch-out reservoir, that is, hydrocarbon-bearing formation in plane can be divided into four zones: bottom edge water zone, underside oil and water zone, middle pure oil zone and above residual water zone. The site of the first well should be assigned to be middle or above pure oil zone, thus the exploration value of this type of reservoir can be recognized correctly. In accordance with the characteristics of seism and geology of low permeability thin sandstone and mudstone alternation layer, the paper applied a set of reservoir prediction technology, that is: (1)seism multi-parameter model identification; (2) using stratum's absorbing and depleting information to predict reservoir's abnormal hydrocarbon-bearing range. With the analysis of the residual resource potential and the research of two petroleum system and the accumulation model, promising objective zones are predicted scientifically. And main exploration aim is the DaRngZi bore in the west of ChangLin basin, and YingTai-SiFangZi middle-upper assembly in Honggang terrace.

NMR studies on synthesized diosgenyl saponin analogs

The identification of six synthesized diosgenyl saponin analogs with up to five sugars was accomplished by NMR studies. A combination of homo- and heteronuclear two-dimensional NMR techniques was utilized to achieve the complete H-1 and C-13 NMR assignments. Copyright (C) 2000 John Wiley & Sons, Ltd.

Time-dependent wavepacket approach to the influence of intense fields on the population of molecular excited states

The influence of laser-field parameters, such as intensity and pulse width, on the population of molecular excited state is investigated by using the time-dependent wavepacket method. For a two-state system in intense laser fields, the populations in the upper and lower states are given by the wavefunctions obtained by solving the Schrodinger equation through split-operator scheme. The calculation shows that both the laser intensity and the pulse width have a strong effect on the population in molecular excited state, and that as the common feature of light-matter interaction (LMI), the periodic changing of the population with the evolution time in each state can be interpreted by Rabi oscillation and area-theorem. The results illustrate that by controlling these two parameters, the needed population in excited state of interest can be obtained, which provides the foundation of light manipulation of molecular processes. (C) 2005 Elsevier B.V. All rights reserved.