Investigation of add-back effects in a segmented Clover detector

The resolution and the summing characteristics of an EXOGAM segmented Clover germanium detector has been studied for use it in gamma spectroscopic experiments. The measurements have been performed with standard radioactive sources of Eu-152, Ba-133 and beta-delayed gamma-rays from Ir-176 decay. The data analytic results, realized by software, are presented in this paper.

延安试区人工刺槐林地的土壤干层分析

8 0年代以来 ,以林草地地力衰退为特征的人工林草地土壤退化日趋严重 ,其中以土壤水分严重亏缺为特征的土壤干化现象愈益引起了人们的重视。土壤干化的直接后果是形成土壤干层 ,导致土壤退化 ,植物生长速率减缓 ,群落衰败以至大片死亡 ,严重地威胁到我国北方地区特别是黄土高原地区生态环境的建设。因此 ,研究和解决土壤干层问题已成为黄土高原植被建设的迫切任务。根据延安试区的土壤水分和植被生长状况调查资料 ,初步分析了不同条件下刺槐人工林地的水分状况。结果表明 :试区刺槐人工林地普遍形成了土壤干层 ,且已相当严重 ;坡向对土壤干层有明显影响 ,阳坡形成的干层较阴坡严重 ;坡度愈大 ,土壤干化愈剧烈 ;林龄对干层严重程度影响不明显。同时 ,研究指出了解决土壤干层问题的意义。

Order-disorder transition in eicosylated polyethyleneimine comblike polymers

Order-disorder transition (ODT) behavior in eicosylated polyethyleneimine (PEI20C) comblike polymer obtained by grafting n-eicosyl group on polyethyleneimine backbone was systematically investigated by the combination of differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), Fourier transform infrared (FTIR) spectroscopy as well as solid-state high resolution nuclear magnetic resonance (NMR) spectroscopy. DSC investigations showed two obvious transitions, assigned to the transitions (1) from orthorhombic to hexagonal and (2) from hexagonal to amorphous phase, respectively. These transitions are induced by the variations of alkyl side chain conformation and packing structure with temperature changing, which consequently lead to the destruction of original phase equilibrium. The ODT behavior can also be confirmed by spectroscopic methods like WAXD, FTIR and NMR. The ordered structure and the transition behavior of the alkyl side chains confined by the PEI backbone are obviously different from those of pristine normal alkanes. The transition mechanism of ODT and the origin of the phase transition behavior in PEI20C comblike polymer were discussed in detail in this paper.

Observation of inverted phases in poly(styrene-b-butadiene-b-styrene) triblock copolymer by solvent-induced order-disorder phase transition

We report observation of inverted phases consisting of spheres and/or cylinders of the majority fraction block in a poly(styrene-b-butadiene-b-styrene) (SBS) triblock copolymer by solvent-induced order-disorder phase transition (ODT). The SBS sample has a molecular weight of 140K Da and a polystyrene (PS) weight fraction of 30%. Tapping mode atomic force microscopy (AFM) and transmission electron microscopy (TEM) were utilized to study the copolymer microstructure of a set of solution-cast SBS films dried with different solvent evaporation rates, R. The control with different R leads to kinetic frozen-in of microstructures corresponding to a different combination parameter chi (eff)Z of the drying films (where chi (eff) is the effective interaction parameter of the polymer solution in the cast film and Z the number of "blobs" of size equal to the correlation length one block copolymer chain contains), for which faster evaporation rates result in microstructures of smaller chi (eff)Z. As R was decreased from rapid evaporations (similar to0.1 mL/h), the microstructure evolved from a totally disordered one sequentially to inverted phases consisting of spheres and then cylinders of polybutadiene (PB) in a PS matrix and finally reached the equilibrium phase, namely cylinders of PS in a PB matrix. We interpret the formation of inverted phases as due to the increased relative importance of entropy as chi (eff)Z is decreased, which may dominate the energy penalty for having a bigger interfacial area between the immiscible blocks in the inverted phases.

南海北部大陆边缘盆地深部地热特征用地球动力学演化

This report is a conclusion of the major research outcome during my post-doctoral residence of research and work. Its content covers the researches of the deep thermal characteristic and dynamics evolution beneath the northern margin basin of South China Sea. In this report, the each other action and effect between lithosphere ad mantle convection were regarded by the combine of deep and shallow study, subdivision from whole to part, and pay equal attention to determine the nature and fixed quantity. The investigative method we used in this report is geothermal and gravity methods. By the help of geological model and geophysics modeling, we calculated lithosphere thermal structure, rheology structure and mantle convection. Firstly, the report introduces concisely the purpose and the previous achievement to this research. Then, it analyzed the characteristic of heat flow on South China Sea. The structure of deep temperature and thermal has been calculated in some models of heat generation and conduction. The rock rheology structure also was computed by the relationship between temperature and viscosity. All these calculations were finished under the guidelines of combine with geology and geophysics. Meanwhile, the fields both deep mantle convection and small scale upper mantle convection are computed. Beside, the density and temperature disorder resulted by mantle convection were also computed with the convection field. After these, the report bring the contribution of local field of mantle convection, thermal construct and effective viscosity beneath the northern margin basin of South China Sea. And, base on the tectonic background and evolution feature, this report discussion the evolution mechanism of south China Sea and its northern margin basin. The end of this report, the main conclusion of this research was summarized and brings out.

不同干扰条件下社会认知偏离者两半球协同功能研究

Previous studies have witnessed some psychological or behavioral deviation (such as aggressive behavior) might have an association with cerebral hemisphere cooperative dysfunction, however, it is still unclear whether there is an association between individuals with social cognitive bias and their hemispheric cooperative functions especially while the interhemisphere cooperative processing is under the conditions of emotional interferences. The purpose of this study is to explore the differences between the social cognitive bias group and the normal group’s interhemispheric cooperative functional activity under the conditions of with or without interferences. Methods: According to Dodge’s (1993) model of “social-cognitive mechanisms in the development of conduct disorder and depression”, a 51 items of “social cognitive bias scale” was created and was used to screen the high score group. 20 male subjects was composed of high score group and other 23 matched the control group. Stimulus tachistoscopically presented to the bilateral visual field and compared with the central. Both group’s interhemispheric cooperative functional activity were observed and compared under the conditions of without interference- i.e. base level and with the emotional interferences of white noise level and negative evaluative feedback speech level while finishing: experiment one: Chinese word-figure Stroop analogue task; experiment two: two single Chinese Characters combination task. Heart rate and respiratory rate were simultaneously recorded as index of emotional changes. Results: ① The high score group showed a decrease in processing accuracy compared with the normal group under the condition of white noise interference level in experiment one. ② Still under the condition of white noise interference level, there were more reaction time and more errors were observed in high score group than normal in experiment two. ③ Both groups showed speed up effect and the strategic processing tendency of speed-accuracy trade-off effect under the condition of white noise interference level in both experiments. ④ Between group differences of interhemipheric cooperative function were not observed under the conditions of base level and the negative evaluative feedback speech level within both experiments. Conclusion: The results suggested that interhemispheric cooperative functional differences exists between the two groups, characterized as ① differences existed in interhemispheric cooperative processing strategy between the two groups, with the high score group presented “hierarchic” deficiency strategy. ② the appearance of the differences between the two groups were condition specified , and in this research it was only under the white noise interference condition. ③ the features of the differences between the two groups were the differences on multidimensional performances and with a deficit orientation in high score group. ④ the varieties of the differences were changing with cooperative tasks, as in this research the high score group performed worse in complementary cooperative task. In addition, both group adjusted the processing strategy respectively under the condition of white noise evoked emotional interference implied that the interaction between the interhemisphere cooperative processing and emotion might exist.

汉语发展性阅读障碍儿童的视觉大细胞通路特点

Developmental dyslexia (DD) is a common kind of learning disorder, which affects 5-18% of people. It seems important to explore the deficit in visual magnocellular pathway in Chinese developmental dyslexia, for many researches demonstrated that one of the core deficits of Chinese developmental dyslexia was orthographic deficit which was associated with the deficit in visual magnocellular pathway. Two studies were done to detect the differences among Chinese developmental dyslexics, average readers of the same chronological age (CA controls) and average readers of the same reading level (RL controls) in reaction time, accuracy and visual mismatch negativity (vMMN) elicited by the moving gratings responded by visual magnocellular pathway. There were two grating-conditions which were low contrast/low spatial frequency condition and high contrast/high spatial frequency condition respectively. In ERP study, a modified “cross-modal delayed response” paradigm was used to elicit the vMMN. The results showed that the developmental dyslexics responded slower than CA controls, had more errors than RL controls, and had smaller amplitudes of vMMNs than the two controls in visual magnocellular pathway condition, but not in control condition. That is to say, Chinese developmental dyslexics had deficits in visual magnocellular pathway.

Postharvest porometer to study transpiration and to measure vapor pressure deficit.

O pôrometro de pós-colheita é um instrumento para medir transpiração, resistência difusiva e déficit de pressão de vapor por manometria a volume constante e por volumetria a pressão constante. É constituído de uma câmara de transpiração com fechamento hermético contendo um suporte de amostras sobre um ventilador e externamente um manômetro de coluna de água com pipeta graduada móvel. Sob temperatura constante, o déficit de pressão de vapor (.P), e o volume de vapor de água (.V) foram proporcionais aos volumes de água vaporizados. Com o uso de um excesso de água este aumento da pressão de vapor iguala-se, em módulo, ao déficit de pressão de vapor do ar na câmara de transpiração. Para amostras do ar atmosférico no laboratório, o déficit de pressão de vapor foi calculado a partir das temperaturas de bulbo seco e úmido em um psicrômetro ventilado e por manometria. A correlação entre estes dois métodos foi de 0,976. A acurácia das medidas de transpiração é tal que o produto do volume morto da câmara (V) pela declividade (.P/ .V) determinada pelo vapor de água liberado no processo iguala-se à pressão barométrica, com erro inferior a 1%. Um exemplo experimental do uso do porômetro de pós-colheita em cenoura é apresentado juntamente e os detalhes para obter a resistência difusiva e espessura da camada laminar. O porômetro de pós-colheita é um porômetro de difusão simples, robusto, que poderá ser usado em estudos de efeito de cêras, na seleção de cultivares e em variados outros estudos de fisiologia de pós-colheita.

Curved Inertia Frames: Visual Attention and Perceptual Organization Using Convexity and Symmetry

In this paper we present an approach to perceptual organization and attention based on Curved Inertia Frames (C.I.F.), a novel definition of "curved axis of inertia'' tolerant to noisy and spurious data. The definition is useful because it can find frames that correspond to large, smooth, convex, symmetric and central parts. It is novel because it is global and can detect curved axes. We discuss briefly the relation to human perception, the recognition of non-rigid objects, shape description, and extensions to finding "features", inside/outside relations, and long- smooth ridges in arbitrary surfaces.

Perceptual Organization, Figure-Ground, Attention and Saliency

Notions of figure-ground, inside-outside are difficult to define in a computational sense, yet seem intuitively meaningful. We propose that "figure" is an attention-directed region of visual information processing, and has a non-discrete boundary. Associated with "figure" is a coordinate frame and a "frame curve" which helps initiate the shape recognition process by selecting and grouping convex image chunks for later matching- to-model. We show that human perception is biased to see chunks outside the frame as more salient than those inside. Specific tasks, however, can reverse this bias. Near/far, top/bottom and expansion/contraction also behave similarly.

The Role of Attention in Binocular Rivalry as Revealed Through Optokinetic Nystagmus

When stimuli presented to the two eyes differ considerably, stable binocular fusion fails, and the subjective percept alternates between the two monocular images, a phenomenon known as binocular rivalry. The influence of attention over this perceptual switching has long been studied, and although there is evidence that attention can affect the alternation rate, its role in the overall dynamics of the rivalry process remains unclear. The present study investigated the relationship between the attention paid to the rivalry stimulus, and the dynamics of the perceptual alternations. Specifically, the temporal course of binocular rivalry was studied as the subjects performed difficult nonvisual and visual concurrent tasks, directing their attention away from the rivalry stimulus. Periods of complete perceptual dominance were compared for the attended condition, where the subjects reported perceptual changes, and the unattended condition, where one of the simultaneous tasks was performed. During both the attended and unattended conditions, phases of rivalry dominance were obtained by analyzing the subject"s optokinetic nystagmus recorded by an electrooculogram, where the polarity of the nystagmus served as an objective indicator of the perceived direction of motion. In all cases, the presence of a difficult concurrent task had little or no effect on the statistics of the alternations, as judged by two classic tests of rivalry, although the overall alternation rate showed a small but significant increase with the concurrent task. It is concluded that the statistical patterns of rivalry alternations are not governed by attentional shifts or decision-making on the part of the subject.

The Role of Fixation and Visual Attention in Object Recognition

This research project is a study of the role of fixation and visual attention in object recognition. In this project, we build an active vision system which can recognize a target object in a cluttered scene efficiently and reliably. Our system integrates visual cues like color and stereo to perform figure/ground separation, yielding candidate regions on which to focus attention. Within each image region, we use stereo to extract features that lie within a narrow disparity range about the fixation position. These selected features are then used as input to an alignment-style recognition system. We show that visual attention and fixation significantly reduce the complexity and the false identifications in model-based recognition using Alignment methods. We also demonstrate that stereo can be used effectively as a figure/ground separator without the need for accurate camera calibration.

Mandibular Manipulation for the Treatment of Temporomandibular Disorder

The aim of this study was to conduct a systematic review to identify the randomized clinical studies that had investigated the following research question: Is the mandibular manipulation technique an effective and safe technique for the treatment of the temporomandibular joint disk displacement without reduction? the systematic search was conducted in the electronic databases: PubMed (Medical Publications), LILACS (Latin American and Caribbean Literature in Health Sciences), EMBASE (Excerpta Medica Database), PEDro (Physiotherapy Evidence Database), BBO (Brazilian Library of Odontology), CENTRAL (Library Cochrane), and SciELO (Scientific Electronic Library Online). the abstracts of presentations in physical therapy meetings were manually selected, and the articles of the ones that meet the requirements were investigated. No language restrictions were considered. Only randomized and controlled clinical studies were included. Two studies of medium quality fulfilled all the inclusion criteria. There is no sufficient evidence to support the effectiveness of the mandibular manipulation therapy, and therefore its use remains questionable. Being minimally invasive, this therapy is attractive as an initial approach, especially considering the cost of the alternative approaches. the analysis of the results suggests that additional high-quality randomized clinical trials are necessary on the topic, and they should focus on methods for data randomization and allocation, on clearly defined outcomes, on a priori calculated sample size, and on an adequate follow-up strategy.

Exploring the compassion deficit debate.

Several recent high profile failures in the UK health care system have promoted strong debate on compassion and care in nursing. A number of papers articulating a range of positions within this debate have been published in this journal over the past two and a half years. These articulate a diverse range of theoretical perspectives and have been drawn together here in an attempt to bring some coherence to the debate and provide an overview of the key arguments and positions taken by those involved. In doing this we invite the reader to consider their own position in relation to the issues raised and to consider the impact of this for their own practice. Finally the paper offers some sense of how individual practitioners might use their understanding of the debates to ensure delivery of good nursing care.