左侧梭状回内文字的字形加工：中文正常阅读者，中文文盲、非中文母语被试的对比研究

Reading is an important human-specific skill obtained through extensive learning experience and is reliance on the ability to rapidly recognize single words. According to the behavioral studies, the most important stage of reading is the representation of “visual word form”, which is independent on surface visual features of the reading materials. The prelexical visual word form representation is characterized by the abstractive and highly effective and precise processing. Neuroimaging and neuropsychological studies have investigated the neural basis underlying the visual word form processing. On the basis of summary of the existing literature, the current thesis aimed to address three fundamental questions involving neural basis of word recognition. First, is there a dedicated neural network that is specialized for word recognition? Second, is the orthographic information represented in the putative word/character selective region (VWFA)? Third, what is the role of reading experience in the genesis of the VWFA, is experience a main driver to shape VWFA instead of evolutionary selectivity? Nineteen Chinese literate volunteers, 5 Chinese illiterates and 4 native English speakers participated in this study, and performed perceptual tasks during fMRI scanning. To address the first question, we compared the differential responses to three categories of visual objects, i.e., faces, line drawings of objects and Chinese characters, and defined the region of interesting (ROI) for the next experiment. To address the second question, Chinese character orthography was manipulated to reveal possible differential responses to real characters, false characters, radical combinations, and stroke combinations in the regions defined by the first experiment. To examine the role of reading experience in genesis of specialization for character, the responses for unfamiliar Chinese characters in Chinese illiterates and native English speakers were compared with that in the Chinese literates, and tracked the change in cortical activation after a short-term reading training in the illiterates. Data were analyzed in two dimensions. Both BOLD signal amplitude and spatial distribution pattern among multi-voxels were used to systematically investigate the responsiveness of the left fusiform gyrus to Chinese characters. Our results provide strong and clear evidence for the existence of functionally specialized regions in the human ventral occipital-temporal cortex. In the skilled readers a region specialized for written words could be consistently found in the lateral part of the left fusiform gyrus, line drawings in the median part and faces in the middle. Our results further show that spatial distribution analysis, a method that was not commonly used in neuroimaging of reading, appears to be a more effective measurement for category specialization for visual objects processing. Although we failed to provide evidence that VWFA processes orthographic information in terms of signal intensitiy, we do show that response pattern of real characters and radical collections in this area is different from that of false characters and random stroke combinations. Our last set of experiments suggests that the selective bias to reading material is clearly experience dependent. The response to unknown characters in both English speakers/readers and Chinese illiterates is fundamentally different from that of the skilled Chinese readers. The response pattern for unknown characters is more similar to that for line drawings rather as a weak version of character in skilled Chinese readers. Short-term training is not sufficient to produce VWFA bias even when tested with learned characters, rather the learned characters generated a overall upward shift of the activation of the left fusiform region. Formation of a dedicated region specialized for visual word/character might depend on long-term extensive reading experience, or there might be a critical period for reading acquisition.

影响汉语阅读能力发展的相关认知因素及其作用的发展变化

The present cross-sectional study paid attention to Chinese reading acquisition of 391 children from preschool to grade 3 in two elementary schools, and investigated the relationship between orthographic processing skills, morphological awareness, phonological awareness, naming, phonological memory, visual processing skill and reading skills, after controlling the variance of age, nonverbal intelligence and pinyin knowledge. The main results are as follows: Firstly, there are many different language skills as the predictors of Chinese reading success. Orthographic processing skills, morphological awareness, phonological awareness and naming are important in single-character recognition and comprehension. Beside them, the effect of visual processing skill and phonological memory for comprehension are also significant. Among them, the role of orthographic processing skills is the most important, whatever in single-character recognition or in comprehension. Secondly, orthographic processing skills are the most important factors in reading acquisition at low grade and its effect drops obviously after grade 2. Thirdly, morphological awareness is also the factor that cannot be ignored whatever for single-character recognition or for comprehension. Its influence appears in preschool and becomes the only significant predictor of character recognition in grade 3. Furthermore, morphological awareness is more relevant with the development of comprehension. Fourthly, phonological awareness plays the secondary role in Chinese reading acquisition except in grade 2 when its contribution is most of all. And compare with morphological awareness, the effect of phonological awareness is relative low. Fifthly, naming is important through preschool to grade 2. The contribution of phonological memory increases from preschool to grade 3 in comprehension.

陆地三分量三维地震勘探技术研究与应用

With the development of oil and gas field exploration, it becomes harder to search new reserves. So a higher demand of seismic exploration comes up. Now 3C3D seismic exploration technology has been applied in petroleum exploration domains abroad. Comparing with the traditional P-wave exploration, the seismic attributes information which provided by 3C3D seismic exploration will increase quickly. And it can derive various combined parameters. The precision of information about lithology, porosity, fracture, oil-bearing properties, etc which estimated by above parameters was higher than that of pure P-wave exploration. These advantages mentioned above lead to fast development of 3C3D seismic technology recently. Therefore, how to apply the technology in petroleum exploration field in China, how to obtain high quality seismic data, and how to process and interpret real data, become frontier topics in geophysical field nowadays, which have important practical significance in research and application. In this paper, according to the propagation properties of P-wave and converted wave, a study of 3C3D acquisition parameters design method was completed. Main parameters included: trace interval, shot interval, maximum offset, bin size, the interval of receiving lines, the interval of shooting lines, migration aperture, maximum cross line distance, etc. Their determination principle was given. The type of 3C3D seismic exploration geometry was studied. By calculating bin attributes and analyzing parameters of geometry, some useful conclusions were drawn. With the method in this paper, real geometries for continental lithology stratum gas reservoir and fractured gas reservoir were studied and determined. In the static method of multi-wave, the near surface P-wave, S-wave parameter investigation method has been advanced, and this method has been applied for the patent successfully; the near surface P-wave, S-wave parameter investigation method and the converted refraction wave first arrival static techniques have been integrally used to improve the effectiveness of converted wave static. In the aspect of converted wave procession, the rotation of horizontal component data, the calculation of converted wave common conversion bin, the residual static of converted wave, the velocity analysis of the common conversion point (CCP), the Kirchhoff pre-stack time migration of converted wave techniques have been applied for setting up the various 3C3D seismic data processing flows based on different geologic targets, and the high quality P-wave, converted-wave profiles have been acquired in the actual data processing. In the aspect of P-wave and converted-wave comprehensive interpretation, the thoughts and methods of using zero-offset S-wave VSP data to calibrate horizon have been proposed; the method of using P-wave and S-wave amplitude ratio to predict the areas of oil and gas enrichment has been studied; the method of inversion using P-wave combined with S-wave has been studied; the various P-wave, S-wave parameters(velocity ratio, amplitude ratio, poisson ratio) have been used to predict the depth, physical properties, gas-bearing properties of reservoirs; the method of predicting the continental stratum lithology gas reservoir has been built. The above techniques have all been used in various 3D3C seismic exploration projects in China, and the better effects have been gotten. By using these techniques, the 3C3D seismic exploration level has been improved.

语音意识缺陷儿童的言语知觉技能

Considerable studies find that developmental dyslexia is associated with deficits in phonological processing skills, especially phonological awareness. In order to explore the nature of phonological awareness deficits in dyslexia, researchers have begun to investigate the role of speech perception. The findings about speech perception abilities in dyslexics are inconsistent. The heterogeneity of dyslexia may be responsible for the inconsistency of findings. Considering the general suggestion that phonological awareness deficits in dyslexia are attributed to categorical perception deficits, it is more direct to examine whether children with phonological awareness difficulties or phonological dyslexia show speech categorization deficits consistently. The present study would investigate whether Chinese children with phonological awareness deficits or phonological dyslexia showed abnormal speech perception. The whole study consisted of two parts. Part I screened children with phonological-awareness deficits from Year 3 kindergartens and examined their abilities of perceiving native category continuum, nonnative category contrasts and non-speech sound series. Part II selected phonological dyslexics from an elementary school as participants, and further explored the relation between phonological deficits and speech perception. The first two experiments of Part II examined separately the abilities to label stimuli in native category continuum and brief stops in different contexts, the last experiment investigated the adaptation effects of different participant groups. The main conclusions are as follows: 1) Children with phonological dyslexia showed categorical perception deficits: they had lower consistency than controls when perceiving stimuli within phonetic categories, especially for the stimuli which were not natural sounds. 2) Children with phonological dyslexia exhibited a general difficulty of perceiving brief segments of stops from different contexts. 3) Children with phonological dyslexia did not show adaptation to repeatedly presented stimuli. Based on the present conclusions and the findings of previous studies, we suggested that the representations of sound stimuli in phonological dyslexics’ brains are different from those in normal children’s; the representations of sound stimuli in dyslexics’ cortical neural networks are more diffuse and inconsistent.

Different protein tyrosine phosphatase superfamilies resulting from different gene reading frames

Protein tyrosine phosphatases (PTPs) are comprised of two superfamilies, the phosphatase I superfamily containing a single low-molecular-weight PTP (lmwPTP) family and the phosphatase II superfamily including both the higher-molecular-weight PTP (hmwPTP) and the dual-specificity phosphatase (DSP) families. The phosphatase I and H superfamilies are often considered to be the result of convergent evolution. The PTP sequence and structure analyses indicate that lmwPTPs, hmwPTPs, and DSPs share similar structures, functions, and a common signature motif, although they have low sequence identities and a different order of active sites in sequence or a circular permutation. The results of this work suggest that lmwPTPs and hmwPTPs/DSPs are remotely related in evolution. The earliest ancestral gene of PTPs could be from a short fragment containing about 90similar to120 nucleotides or 30similar to40 residues; however, a probable full PTP ancestral gene contained one transcript unit with two lmwPTP genes. All three PTP families may have resulted from a common ancestral gene by a series of duplications, fusions, and circular permutations. The circular permutation in PTPs is caused by a reading frame difference, which is similar to that in DNA methyltransferases. Nevertheless, the evolutionary mechanism of circular permutation in PTP genes seems to be more complicated than that in DNA methyltransferase genes. Both mechanisms in PTPs and DNA methyltransferases can be used to explain how some protein families and superfamilies came to be formed by circular permutations during molecular evolution.