贵阳市大气总悬浮颗粒物(TSP)的化学特征及其影响因素研究

气溶胶对气候和人类的健康都有重要影响。因此，研究大气总悬浮颗粒物（TSP）的化学组成和物理特性对更深入地了解气溶胶对气候和人类健康的影响具有重要意义。贵阳是中国受燃煤污染比较严重的城市之一，大气中高含量的SO2是其最明显的特征。尽管最近几年空气质量有所改善，但是该区的大气污染问题还比较严重，空气质量仍然不容乐观。我们于2005年1月1日到2005年12月31日在中科院地球化学研究所内全年采集总悬浮颗粒物（TSP）样品，分析测试了其主要无机离子（F-、Cl-、SO42-、NO3-、NH4+、K+、Na+、Ca2+和Mg2+）的化学性质，并结合当地的气象参数（温度，风速，降雨量和相对湿度）系统地研究了TSP及其水溶性无机离子的季节变化特征。本论文的主要结论有： 1. TSP的浓度变化范围为36.91～313.44µg/m3，年均值106.60µg/m3；各离子摩尔浓度的大小顺序为：SO42-> NH4+> Ca2+ > NO3-> K+ > Na+ > Cl- > Mg2+ > F-；SO42- (23.04±12.16µg/m3)和NH4+(3.05±2.23µg/m3)是最主要的离子，分别占总离子摩尔数的37％和30％。TSP及其组分都有明显的季节变化，TSP、Cl-、SO42-、NO3-、NH4+、K+、Na+、Ca2+和Mg2+浓度的冬/夏比值分别为:1.29、5.23、1.35、2.37、1.73、1.22、1.84、1.23和1.02。 2. 温度对TSP及其水溶性无机组分的影响呈现一定的季节变化模式，冬天随温度的升高TSP及其水溶无机组分的浓度也升高，夏天随温度的升高TSP及其水溶性无机组分的浓度降低。但是从全年来看，温度与TSP及其水溶性无机组分之间有弱的负相关性，即随温度的升高，TSP及其水溶性无机组分的浓度有不同程度的下降。相对湿度与TSP及其水溶性无机组分之间存在明显的负相关关系，即随大气相对湿度的增加，TSP及其水溶性无机组分的浓度下降。在相对湿度与TSP及其水溶性无机组分浓度的日变化图中表现为相对湿度的波谷与TSP及其水溶无机组分的浓度的波峰相对应。风速与TSP及其水溶无机组分的浓度之间呈现弱的负相关性。在贵阳，风速对TSP及其水溶无机组分的影响主要表现为扩散作用和稀释作用，由风速导致的尘土再悬浮作用并不明显。雨量对TSP及其水溶性无机组分的影响主要是湿清除作用，具体表现为无雨天TSP及其水溶性无机组分的浓度较雨天高。影响TSP、Ca2+、Mg2+和F-的主要气象参数是相对湿度(RH)和风速，影响SO42-、NO3-、NH4+和Cl-的主要气象参数是温度。 3. 贵阳大气总悬浮颗粒物（TSP）总体偏酸性，TSP水溶液pH值的年均值为6.27±0.41，与总阴离子与总阳离子的当量比Q的年平均值为0.82一致；TSP中高含量的SO42-是贵阳的TSP显酸性的主要原因。 4. NH4+与SO42-和NO3-的相关系数（R）分别为0.85和0.65，NH4+与SO42-的摩尔比值为0.8，说明贵阳TSP中的NH4+主要以(NH4)2SO4的形式存在。Ca2+和Mg2+有较好的相关性（R=0.72）和相似的变化特征，说明二者可能有共同的来源。 5. 2005年贵阳TSP中SO42-/ Ca2+的平均值为13.64，几乎是干净大陆SO42-/ Ca2+的本底值的20倍，说明贵阳的大气污染主要是人为因素所致。NO3-/SO42-的平均值为0.15，说明固定源对贵阳气溶胶的贡献比移动源（通常指交通工具所排放的尾气）对气溶胶的贡献大；

Volume-Time Curve: An Alternative for Endotracheal Tube Cuff Management

BACKGROUND: Despite numerous studies on endotracheal tube cuff pressure (CP) management, the literature has yet to establish a technique capable of adequately tilling the cuff with an appropriate volume of air while generating low CP in a less subjective way. the purpose of this prospective study was to evaluate and compare the CP levels and air volume required to fill the endotracheal tubes cuff using 2 different techniques (volume-time curve versus minimal occlusive volume) in the immediate postoperative period after coronary artery bypass grafting. METHODS: A total of 267 subjects were analyzed. After the surgery, the lungs were ventilated using pressure controlled continuous mandatory ventilation, and the same ventilatory parameters were adjusted. Upon arrival in the ICU, the cuff was completely deflated and re-inflated, and at this point the volume of air to fill the cuff was adjusted using one of 2 randomly selected techniques: volume-time curve and minimal occlusive volume. We measured the volume of air injected into the cuff, the CP, and the expired tidal volume of the mechanical ventilation after the application of each technique. RESULTS: the volume-time curve technique demonstrated a significantly lower CP and a lower volume of air injected into the cuff, compared to the minimal occlusive volume technique (P < .001). No significant difference was observed in the expired tidal volume between the 2 techniques (P = .052). However, when the subjects were submitted to the minimal occlusive volume technique, 17% (n = 47) experienced air leakage as observed by the volume-time graph. CONCLUSIONS: the volume-time curve technique was associated with a lower CP and a lower volume of air injected into the cuff, when compared to the minimal occlusive volume technique in the immediate postoperative period after coronary artery bypass grafting. Therefore, the volume-time curve may be a more reliable alternative for endotracheal tube cuff management.

Xanthine oxidase pathway and muscle damage: Insights from McArdle disease

The intent of this review is to summarize current body of knowledge on the potential implication of the xanthine oxidase pathway (XO) on skeletal muscle damage. The possible involvement of the XO pathway in muscle damage is exemplified by the role of XO inhibitors (e.g., allopurinol) in attenuating muscle damage. Reliance on this pathway (as well as on the purine nucleotide cycle) could be exacerbated in conditions of low muscle glycogen availability. Thus, we also summarize current hypotheses on the etiology of both baseline and exertional muscle damage in McArdle disease, a condition caused by inherited deficiency of myophosphorylase. Because myophosphorylase catalyzes the first step of muscle glycogen breakdown, patients are unable to obtain energy from their muscle glycogen stores. Finally, we provide preliminary data from our laboratory on the potential implication of the XO pathway in the muscle damage that is commonly experienced by these patients.

Biological rationale for regular physical exercise as an effective intervention for the prevention and treatment of depressive disorders

Depression is a major medical and social problem. Here we review current body of knowledge on the benefits of exercise as an effective strategy for both the prevention and treatment of this condition. We also analyze the biological pathways involved in such potential benefits, which include changes in neurotrophic factors, oxidative stress and inflammation, telomere length, brain volume and microvessels, neurotransmitters or hormones. We also identify major caveats in this field of research: further studies are needed to identify which are the most appropriate types of exercise interventions (intensity, duration, or frequency) to treat and prevent depression.

Fusion ARTMAP: An Adaptive Fuzzy Network for Multi-Channel Classification

Fusion ARTMAP is a self-organizing neural network architecture for multi-channel, or multi-sensor, data fusion. Fusion ARTMAP generalizes the fuzzy ARTMAP architecture in order to adaptively classify multi-channel data. The network has a symmetric organization such that each channel can be dynamically configured to serve as either a data input or a teaching input to the system. An ART module forms a compressed recognition code within each channel. These codes, in turn, beco1ne inputs to a single ART system that organizes the global recognition code. When a predictive error occurs, a process called parallel match tracking simultaneously raises vigilances in multiple ART modules until reset is triggered in one of thmn. Parallel match tracking hereby resets only that portion of the recognition code with the poorest match, or minimum predictive confidence. This internally controlled selective reset process is a type of credit assignment that creates a parsimoniously connected learned network.

Comparative performance of multiview stereoscopic and mammographic display modalities for breast lesion detection.

PURPOSE: Mammography is known to be one of the most difficult radiographic exams to interpret. Mammography has important limitations, including the superposition of normal tissue that can obscure a mass, chance alignment of normal tissue to mimic a true lesion and the inability to derive volumetric information. It has been shown that stereomammography can overcome these deficiencies by showing that layers of normal tissue lay at different depths. If standard stereomammography (i.e., a single stereoscopic pair consisting of two projection images) can significantly improve lesion detection, how will multiview stereoscopy (MVS), where many projection images are used, compare to mammography? The aim of this study was to assess the relative performance of MVS compared to mammography for breast mass detection. METHODS: The MVS image sets consisted of the 25 raw projection images acquired over an arc of approximately 45 degrees using a Siemens prototype breast tomosynthesis system. The mammograms were acquired using a commercial Siemens FFDM system. The raw data were taken from both of these systems for 27 cases and realistic simulated mass lesions were added to duplicates of the 27 images at the same local contrast. The images with lesions (27 mammography and 27 MVS) and the images without lesions (27 mammography and 27 MVS) were then postprocessed to provide comparable and representative image appearance across the two modalities. All 108 image sets were shown to five full-time breast imaging radiologists in random order on a state-of-the-art stereoscopic display. The observers were asked to give a confidence rating for each image (0 for lesion definitely not present, 100 for lesion definitely present). The ratings were then compiled and processed using ROC and variance analysis. RESULTS: The mean AUC for the five observers was 0.614 +/- 0.055 for mammography and 0.778 +/- 0.052 for multiview stereoscopy. The difference of 0.164 +/- 0.065 was statistically significant with a p-value of 0.0148. CONCLUSIONS: The differences in the AUCs and the p-value suggest that multiview stereoscopy has a statistically significant advantage over mammography in the detection of simulated breast masses. This highlights the dominance of anatomical noise compared to quantum noise for breast mass detection. It also shows that significant lesion detection can be achieved with MVS without any of the artifacts associated with tomosynthesis.

SOLO AND CHAMBER CLARINET WORKS BY AMERICAN- BORN WOMEN COMPOSERS: 1990-2005

During the period of 1990-2005, American-born women composers have contributed significantly to the standard clarinet repertoire. Pioneering composers such as Joan Tower, Margaret Brouwer, and Libby Larsen have created staples for clarinet literature. Yet, there is very little scholarly research on women composers of clarinet music, most being concentrated on Joan Tower. Through my research, I have discovered over seventy-five works by more than fifty composers in the following genres: solo clarinet; clarinet and piano; clarinet and voice, with or without piano; and small chamber pieces for up to five players. This performance dissertation project consists of three recitals featuring solo and chamber works by nine living women composers, and program notes containing pertinent biographical and compositional information. My intent is to increase recognition women composers, both prominent and lesser known, who are writing high-quality, accessible clarinet literature. Each woman selected is making a full or partial living from the sales of her compositions, has received recognition through awards, commissions, grants, and frequent performances, and has composed works that are both performer and audience accessible. Recital 1: Trios for Clarinet, Violin, and Piano Commissioned by the Verdehr Trio and Composed by American-Born Women Composers. Composers: Jennifer Higdon, Joan Tower, Margaret Brouwer, and Libby Larsen. Recital II: Programmatic Clarinet Works by American-Born Women Composers. Composers: Andrea Clearfield, Stella Sung, and Karen Amrhein. Recital III: Works for Solo Clarinet, Clarinet and Piano, and Clarinet Concerto Genres by American-Born Women Composers. Composers: Persis Parshall Vehar, Jenni Brandon, Margaret Brouwer, and Libby Larsen.

Spin three gauge theory revisited

We study the problem of consistent interactions for spin-3 gauge fields in flat spacetime of arbitrary dimension 3$">n>3. Under the sole assumptions of Poincaré and parity invariance, local and perturbative deformation of the free theory, we determine all nontrivial consistent deformations of the abelian gauge algebra and classify the corresponding deformations of the quadratic action, at first order in the deformation parameter. We prove that all such vertices are cubic, contain a total of either three or five derivatives and are uniquely characterized by a rank-three constant tensor (an internal algebra structure constant). The covariant cubic vertex containing three derivatives is the vertex discovered by Berends, Burgers and van Dam, which however leads to inconsistencies at second order in the deformation parameter. In dimensions 4$">n>4 and for a completely antisymmetric structure constant tensor, another covariant cubic vertex exists, which contains five derivatives and passes the consistency test where the previous vertex failed. © SISSA 2006.

Expression of the Ets transcription factor Erm is regulated through a conventional PKC signaling pathway in the Molt4 lymphoblastic cell line.

Erm, a member of the PEA3 group within the Ets family of transcription factors, is expressed in murine and human lymphocytes. Here, we show that in the human Molt4 lymphoblastic cell line, the erm gene expression is regulated by the conventional PKC (cPKC) pathway. To better characterize the molecular mechanism by which cPKC regulates Erm transcription in Molt4 cells, we tested proximal promoter deletions of the human gene, and identified a specific cPKC-regulated region between positions -420 and -115 upstream of the first exon.

Creativity and entrepreneurial efforts in an emerging economy

While much research has focused on entrepreneurship and creativity in developed economies, the notions of both topics are still embryonic in many emerging economies. This paper focuses on entrepreneurs in one such economy, Vietnam, to understand the perceptions of entrepreneurs about the role that innovation and creativity may play in their own entrepreneurial ventures and success. This is important because before reaping benefits from entrepreneurship, entrepreneurs need to decide when and on what conditions they start based on their calculations of required resources and predictions of likely outcomes. The research also sought to understand how "creativity," broadly applied ("innovation" and "creative performance") affects the ways that entrepreneurs think about and anticipate their own success and decisions. In essence, the study suggests that the higher the entrepreur’s creativity is, the more likely she or he is to start a new business and believe success will result. Future research could examine whether history, industry and geographic location matter in entrepreneurs’ perceptions as well as whether transition/emerging economies like Vietnam may have different views altogether about the two key concepts.

The effects of cadence and power output upon physiological and biomechanical responses to incremental arm-crank ergometry

The aim of this study was to examine the effects of cadence and power output on physiological and biomechanical responses to incremental arm-crank ergometry (ACE). Ten male subjects (mean +/- SD age, 30.4 +/-5.4 y; height, 1.78 +/-0.07 m; mass, 86.1 +/-14.2 kg) undertook 3 incremental ACE protocols to determine peak oxygen uptake (VO2 peak; mean of 3 tests: 3.07 +/- 0.17 L.min-1) at randomly assigned cadences of 50, 70, or 90 r.min-1. Heart rate and expired air were continually monitored. Central (RPE-C) and local (RPE-L) ratings of perceived exertion were recorded at volitional exhaustion. Joint angles and trunk rotation were analysed during each exercise stage. During submaximal power outputs of 50, 70, and 90 W, oxygen consumption (VO2) was lowest for 50 r.min-1 and highest for 90 r.min-1 (p < 0.01). VO2 peak was lowest during 50 r.min-1 (2.79 +/-0.45 L.min-1; p < 0.05) when compared with both 70 r.min-1 and 90 r.min-1 (3.16 +/-0.58, 3.24 +/-0.49 L.min-1, respectively; p > 0.05). The difference between RPE-L and RPE-C at volitional exhaustion was greatest during 50 r.min-1 (2.9 +/- 1.6) when compared with 90 r.min-1 (0.9 +/- 1.9, p < 0.05). At VO2 peak, shoulder range of motion (ROM) and trunk rotation were greater for 50 and 70 r.min-1 when compared with 90 r.min-1 (p < 0.05). During submaximal power outputs, shoulder angle and trunk rotation were greatest at 50 r.min-1 when compared with 90 r.min-1 (p < 0.05). VO2 was inversely related to both trunk rotation and shoulder ROM during submaximal power outputs. The results of this study suggest that the greater forces required at lower cadences to produce a given power output resulted in greater joint angles and range of shoulder and trunk movement. Greater isometric contractions for torso stabilization and increased cost of breathing possibly from respiratory-locomotor coupling may have contributed increased oxygen consumption at higher cadences.

Experimental and Modelling Studies of the Thermodynamics and Kinetics of Phase and Structural Transformations in a Gamma TiAl-based Alloy

This work combines microscopy, synchrotron radiation X-ray diffraction, differential scanning calorimetry and thermodynamic calculations in the characterisation of phase transformation behaviour of a Ti–46Al–1.9Cr–3Nb alloy upon continuous heating at constant rates. It has been found that the Ti–46Al–1.9Cr–3Nb alloy after being forged at 1200 °C without further treatment has a duplex microstructure consisting of fine equiaxed and lamellar ? grains with a small amount of a2 plates and particles and about 1 wt.% B2 phase. Differential scanning calorimetry revealed reproducibly several thermal effects upon heating of the as-forged alloy. These thermal effects are related to the equilibration and homogenisation of the sample, change of phase ratios between a2, ? and B2 phases in particular the increase of B2 in respect to a2 and ?, and the following five phase transformations: a2 + ? + B2 a + ? + B2, a + ? + B2 a + ?, ? + a a, a a + ß, a + ß a + ß + L. The observation of these transformations by differential scanning calorimetry is largely in agreement with literature phase diagrams and thermodynamic calculations, though care is needed to consider the different alloy compositions. Kinetics of the ? + a a phase transformation in the Ti–46Al–1.9Cr–3Nb alloy has been quantitatively derived from the calorimetry data, giving phase compositions at any point during the transformation upon continuous heating.

Psychotic symptoms in Alzheimer's disease are not influenced by polymorphic variation at the dopamine receptor DRD3 gene

It has been suggested that genetic influences unmasked during neurodevelopment to produce schizophrenia may appear throughout neurodegeneration to produce AD plus psychosis. Risk of schizophrenia and psychosis in Alzheimer's disease (AD) has been linked to polymorphic variation at the dopamine receptor DRD3 gene implying similar causative mechanisms. We tested this association in a large cohort of Alzheimer's disease patients with a diagnosis of probable AD of 3 years or more duration from the relatively genetically homogenous Northern Irish population. We assessed relationships between genotypes/alleles of the DRD3 BalI polymorphism and the presence or absence of psychotic symptoms (delusions, hallucinations) in AD patients during the month prior to interview and at any stage during the dementia. No significant associations were found when delusions and hallucinations were cross-tabulated against S and G alleles and SS, SG and GG genotypes. Logistic regression failed to detect any influence of APOE, gender, family history or prior psychiatric history. In conclusion, we were unable to confirm previously reported associations between the DRD3 BalI polymorphism and psychotic symptoms in AD.

Components of resistance to Fusarium head blight in wheat detected in a seed germination assay with Microdochium majus and the relationship to FHB disease development and mycotoxin accumulation from Fusarium graminearum infection.

Components of partial disease resistance (PDR) to fusarium head blight (FHB), detected in a seed-germination assay, were compared with whole-plant FHB resistance of 30 USA soft red winter wheat entries in the 2002 Uniform Southern FHB Nursery. Highly significant (P <0·001) differences between cultivars in the in vitro seed-germination assay inoculated with Microdochium majus were correlated to FHB disease incidence (r = -0·41; P <0·05), severity (r = -0·47; P <0·01), FHB index (r = -0·46; P <0·01), damaged kernels (r = -0·52; P <0·01), grain deoxynivalenol (DON) concentration (r = -0·40; P <0·05) and incidence/severity/kernel-damage index (ISK) (r = -0·45; P <0·01) caused by Fusarium graminearum. Multiple linear regression analysis explained a greater percentage of variation in FHB resistance using the seed-germination assay and the previously reported detached-leaf assay PDR components as explanatory factors. Shorter incubation periods, longer latent periods, shorter lesion lengths in the detached-leaf assay and higher germination rates in the seed-germination assay were related to greater FHB resistance across all disease variables, collectively explaining 62% of variation for incidence, 49% for severity, 56% for F. graminearum-damaged kernels (FDK), 39% for DON and 59% for ISK index. Incubation period was most strongly related to disease incidence and the early stages of infection, while resistance detected in the seed germination assay and latent period were more strongly related to FHB disease severity. Resistance detected using the seed-germination assay was notable as it related to greater decline in the level of FDK and a smaller reduction in DON than would have been expected from the reduction in FHB disease assessed by visual symptoms.