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There is growing evidence that air pollution plays a role in TB, but few studies have comprehensively included the six common air pollutants. Our objectives were to investigate the association between short-term exposure to six common air pollutants and the risk of tuberculosis outpatient visits in Fuyang, China, during the period 2015-2020. We combined the two models to explore the effects of exposure to six air pollutants on the risk of tuberculosis outpatient visits, including Poisson generalized linear regression model and distributed lag non-linear model (DLNM). We performed stratified analyses for season, gender and age. We used the lag-specific relative risks and cumulative relative risk obtained by increasing pollutant concentration by per 10 units to evaluate the connection between six air pollutants and TB, PM2.5 (RR=1.0018, 95%CI: 1.0004-1.0032, delay of 12 days) and (RR=1.0169,95%CI: 1.0007-1.0333, lag 0-16 days), SO2 were 0.9549 (95%CI: 0.9389-0.9712, lag 0 days) and 0.8212 (95%CI: 0.7351-0.9173, 0-20 days lag). Stratified analyses showed that seasonal differences had a greater impact on TB, and male more likely to develop TB than female, older people more likely to develop TB than younger people. Exposure to O3, CO, PM10, PM2.5, and NO2 increases the risk of TB outpatient visits, except SO2 reduces the risk. Male and elderly people should be protected. We need to pay more attention to the impact of seasonal effects on TB.

The solidification process and microstructure of Al-7Si-0.3Mg alloy with different rare earth (RE) additions have been studied by using thermal analysis, optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results showed that the addition of RE enhanced the liquidus temperature and decreased the growth temperature of eutectic Si, which lead to obvious increase in solidification interval of the studied alloy. In addition, the grain size of primary α-Al had no obvious change, and the mean area of eutectic Si particles decreased with increasing RE content to 1.6 wt.%. The RE-rich compounds with different compositions were obtained with increasing RE concentration in Al-7Si-0.3Mg alloys. The method of phase diagram calculation helps to clarify the formation and growth mechamism of different RE-rich phases during solidification.

Semi-solid aluminum slurries have globular grains, different from traditional dendritic solidification microstructures. The mechanism responsible for the formation of these globular grains is still in dispute. Some researchers suggest that the globular grains are formed by fractured dendrites, while others report it is due to copious nucleation. This study will model the growth of the α-Al phase during the production of semi-solid slurries using the swirled equilibrium enthalpy device (SEED) process, where liquid alloy with a low superheat is poured into a steel crucible and swirled within the semi-solid region. Experimental observations have shown that the final microstructure of the slurry produced by the SEED process is relatively non-uniform, with large dendrites at surface and fine spherical particles at the center. Open source code for the phase field method has been adopted to simulate the different microstructural evolution for semi-solid alloy 357.0. The effect of localized temperatures under isothermal condition on the morphology of the α-Al particles has been investigated according to the special conditions of the SEED process. In addition, suggestions for modifying the slurry production to achieve more uniform microstructure are discussed.

Microstructures with fine globular grains and refined eutectic structures are important to enhance the mechanical properties of A356 alloys processed by semi-solid and gravity die casting. Rare earth (RE) additions have been shown to be capable of refining both the α-Al particles as well as modify the eutectic phase of alloys. In semi-solid die casting, Al7Si0.3Mg alloys with RE concentrations (0, 0.1 and 0.4 wt.%) were used to prepare semi-solid slurries using the SEED (Swirling Enthalpy Equilibrium Device) method, and subsequently semi-solid die cast. The same compositions of alloys were also applied to gravity die casting. The microstructure and mechanical properties of castings in two processes have been characterized. Compared to the grains produced in gravity die casting, globular grains with small size (260 μm) in the semi-solid die casting significantly enhance the UTS and elongation of alloys. Although the size of grains had no change with increasing RE concentrations in alloys. The Al-Si eutectics were changed to refined morphology with the 0.1 wt.% RE addition, which enhanced the ductility of alloys in two processes. When increasing the RE addition to 0.4 wt.%, the RE-rich phases precipitated at grain boundaries, which decreased the UTS and elongation of alloys.

The reservoirs of Kela 2 gas field are mainly thick-very thick-bedded sandstone inter-bedded with mudstone. In the past 15 years of high-speed development, Kela 2 gas field has been facing the challenge of inhomogeneous water invasion. In order to understand the water invasion laws, based on seismic, logging, core, and production dynamic data, the characteristics of the non- pay interlayers and their sealing ability are analyzed. Then the effects of interlayer, faults, fractures as well as the high permeability formations on the migration of edge and bottom water were discussed. The research results show that: (1) Mudstone interlayers can be divided into two types, one is continuously distributed in the whole area with a thickness of about 10−50 m, the other is discontinuously distributed in the field with an individual thickness generally less than 2 m. (2) The interlayer sealing ability is closely related to the thickness of interlayer and fault throw. The interlayer at top of the Baxigai Formation, together with the interlayers at bottom of the Bashijiqike Formation has a stronger sealing ability than the others. (3) Controlled by the geological characteristics of the gas field, water invasion laws are varied in the different regions. In the west and east regions, Edge water can induce the seriously inhomogeneous water invasion through the relatively high permeability layer; while in the south-central region, the bottom water invasion is relatively moderate because the thick-bedded interlayer weakens the energy of water from deeper bed; in addition, in the SW region, bottom water breakthroughs along faults vertically and then invades along the natural fractures and the relatively high permeability layer, which led to water flooding of gas wells in the area. This study is of great significance to water control and stable production of the gas field.

In the multi-stage evolution process, the fault-related folds in the Kuqa depression are derived or associated with a large number of structural fractures, and the spatial distribution is very complicated. It is of great significance for gas field development to know the distribution law and main control factors of fractures. Taking Dabei, Keshen, Dina2 and Kela2 gas fields as examples, the fracture development characteristics of different fold types are analyzed by using core, imaging logging and seismic data, and the control effect of fold style evolution on fracture development is revealed by using finite element simulation method. Fracture development has obvious correlation with reservoir quality and fold style. The density of fractures in Dabei and Keshen gas fields with low porosity are much higher than that in Dina and Kela gas fields with relatively high porosity. Dabei and Keshen anticlines, are dominated by shear network fractures and exist less tension fractures due to their low amplitude (relatively large interlimb angle), while the tension fracture proportion increases within Dina and Kela anticlines due to their high amplitude (relatively small interlimb angle). The high-value areas of tension fracture is mainly located near the cores of anticlines and the faults, while that of shear fracture is obviously correlation with faults. Further study shows that open folds with interlimb in range of 120o–70o have significant influence and controlling on effectiveness of fractures, but they are not apparent in the gentle folds with interlimb angle in range of 180o–120o. The fracture development heterogeneity of the imbricated double thrust structure with very different scale fracture is stronger than that of the back thrust structure with relatively small scale difference fracture. Finite element simulation showing the development and distribution of structural fractures are obviously controlled by fold uplifting amplitude, distance from fault plane and fault sliding displacement, especially when the fold uplifting amplitude is in the range of 410–450 m, the fracture density value is the largest. This study has effective guidance for development plan of newly discovered gas fields and comprehensive management of developed gas fields of the piedmont thrust belt in Kuqa depression.

ObjectivePulmonary tuberculosis (TB) is a severe infectious respiratory disease, the burden of which remains high in China. To provide scientific evidence for developing more targeted prevention and control strategies, this study aimed to determine the incidence trends and explore the epidemiological characteristics of pulmonary TB in Anhui Province, Eastern China between 2013 and 2018.MethodsThe retrospective study analyzed information regarding pulmonary TB cases reported by the National Infectious Disease Reporting System and census data collected from the Anhui Provincial Bureau of Statistics.ResultsOverall, 211,892 cases of TB patients were reported in Anhui Province, China between 2013 and 2018, with an average annual reported incidence rate of 57.7 per 100,000 persons. A significant decrease in the incidence rate of pulmonary TB (p < 0.001) was observed during the study period. Men had a higher incidence rate of pulmonary TB than women (p < 0.001). The highest annual average reported incidence rate was 204.2 per 100,000 persons in those aged 70-74 years. The number of farmers with pulmonary TB, i.e., 155,415, accounted for 73.4% of all cases. Moreover, the peak period of reported cases was from January to March. Four cities along the Yangtze River-Anqing, Tongling, Chizhou, and Wuhu-reported significantly higher incidence rates of pulmonary TB than other cities (p < 0.001).ConclusionsFrom 2013 to 2018, there was a significant decline in the incidence rate of pulmonary TB in Anhui Province, with peaks occurring from January to March. Prevention and control strategies targeting men, people aged 70-74 years, farmers, and the four cities along the Yangtze River should be strengthened.

Laser additive manufacturing (LAM) technology was applied to prepare Ti-22Al-25Nb alloy thin-wall sample. The characteristics and evolution mechanism of solidification microstructure were investigated, and the tensile properties at horizontal and vertical directions were discussed. The results indicated that the solidification microstructure in single deposition layer evolved as: plane crystal structure, cellular crystal structure, columnar dendrite structure and equiaxed dendrite structure, from the bottom to the top of the molten pool. During the solidification process, the temperature gradient and solidification velocity decided the grain growth morphology. However, the grain of the as-deposited materials grew up to thick equaxied structure when the upper layer was forming. The tensile properties at horizontal and vertical directions were not much different, both of these exhibited high strength and low ductility.

The depression behavior and mechanism of guar gum on talc-type scheelite flotation were systematically investigated by flotation experiments, adsorption tests, zeta-potential measurements, and infrared spectroscopic analyses. The flotation results for monominerals, mixed minerals, and actual mineral samples indicated that guar gum exhibited much higher selective depression for talc than for scheelite. Bench-scale closed-circuit tests showed that a tungsten concentrate with a WO3 grade of 51.43% and a WO3 recovery of 76.18% was obtained. Adsorption tests, zeta-potential measurements, and infrared spectral analyses confirmed that guar gum absorbed more strongly onto the talc surface than onto the scheelite surface because of chemisorption between guar gum and talc. This chemisorption is responsible for the guar gum’s highly selective depression for talc and small depression for scheelite. The flotation results provide technical support for talc-type scheelite flotation.

The approximately equimolar ratio AlCrNiSiTi multi-principal element alloy (MPEA) coatings were fabricated by laser cladding on Ti–6Al–4V (Ti64) alloy. Scanning electron microscopy (SEM), equipped with an energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD) were used to characterize the microstructure and composition. Investigations show that the coatings consist of (Ti, Cr)5Si3 and NiAl phases, formed by in situ reaction. The phase composition is initially explicated according to obtainable binary and ternary phase diagrams, and the formation Gibbs energy of Ti5Si3, V5Si3 and Cr5Si3. Dry sliding reciprocating friction and wear tests of the AlCrNiSiTi coating and Ti64 alloy substrate without coating were evaluated. A surface mapping profiler was used to evaluate the wear volume. The worn surface was characterized by SEM–EDS. The hardness and wear resistance of the AlCrNiSiTi coating are well compared with that of the basal material (Ti64). The main wear mechanism of the AlCrNiSiTi coating is slightly adhesive transfer from GCr15 counterpart, and a mixed layer composed of transferred materials and oxide is formed.

The Keshen gas field in the Kuqa depression of the Tarim Basin with characteristics of deep buried depth, tight matrix and developed fracture, has great differences in gas well productivity within different parts of the structure, which bring difficulties to the gas field development and deployment. Based on the study of the reservoir matrix property, fracture characteristics and individual well productivity of the Keshen ultra-deep gas reservoirs, combined with reservoir geostress research, the difference between high and low efficiency wells in Keshen2 block is analysed, and the main geological factors influencing productivity are revealed. It is found that the effectiveness of reservoir fracture is a necessary condition for high production of gas well. Further study shows that there is a negative correlation between the open flow of gas well and the effective normal stress of fracture. The larger the effective normal stress of fracture is, the more difficult it is to achieve high production with reservoir reconstruction. According to study of the productivity influencing factors of the fractured tight sandstone reservoirs, some suggestions on well deployment and well perforation are given in the paper, which are beneficial to increase production and efficiency of this kind of reservoirs.

With the development of information technology, learning analysis has increasingly become the focus of research. Based on the concept and characteristics of learning analysis, this paper discussed the modeling mechanism of learners' online learning behavior, put forward the analysis model of online learning behavior from the perspective of learning analysis, and carried out empirical analysis, taking as example the learners 'online learning behavior of Shanghai Open University.

A self-developed magnetic detector is presented, which is made up with 64 Hall sensors assembled as an 8×8 serried array in a 50×50mm quadrate circuit wafer, to catch a weak transient magnetic field. The disadvantage accompanying with compact design is the sharp rise of sensor’s working temperature due to the power consumed is on increasing. An approach in which the 64 Hall elements are connected as a three dimensional magnetic-pixel matrix and are driven by dynamic power is presented. The homologous hardware correction illustrative diagram is provided, including its measuring principle and multivariate calibration technique. The experimental results indicated that the proposed method is a beneficial exploration for sensor power supply.

Laser powder deposition was applied to fabricate the Ti–6.5Al–3.5Mo–1.5Zr–0.3Si (wt%)/Ti–47Al–2Cr–2Nb–0.2W–0.15B (at%) bi-material system. The as-deposited TC11 alloy shows a basket-wave-like morphology while the as-deposited γ-TiAl alloy consists of fully α2/γ lamellar microstructures. Regarding the thermal mismatch between TC11 and γ-TiAl during processing, the interface microstructure evolution was concerned. The transformation pathway was illustrated. It is found that the content changes of Al elements and β-stabilizers Mo, Cr, and Nb are responsible for the evolution of microstructures at the interface. The fracture surfaces are located at the γ-TiAl side. The bi-material shows a brittle-fracture manner, with the ultimate tensile strength of 560 MPa.

There exist multi-field coupling effect in prefabricated defects polymer materials under loading. For understanding the pyromagnetic effect, it is crucial to accurately measure the coupling relations of the key physical quantities about displacement, tensile load, temperature, and magnetic field. To overcome the obstacle in current measurement systems for synchronized measurement, an integrated measurement system for multi-field coupling detection is presented to enable synchronized, automatic detection. This paper introduces the system structure, software design, and the detailed design of varied-speed PID control methods. Test results show that, the system is effective for valid data acquisition for displacement, tension load, temperature and magnetic field of a high polymer Polyvinyl Chloride (PVC) plate sample under constant tensile load, and all test data can be visualized on the software interface. This system provides a good test platform for further research on pyromagnetic effect of PVC plate.

Based on the theory of multi-body system dynamics, the analytical method of finite element and boundary element, the finite element model of vehicle body, the rigid-flexible coupled model of vehicle and the acoustic boundary element model of carriage were established by applying a variety of simulation software. Road roughness was simulated and the SPL of field point in carriage under the excitation was computed at the frequency range of 20-150Hz. Considering the size and the positive /negative nature of panels acoustic contribution at SPL peak of field point, damping treatments were taken on different combinations of panels to decrease multiple field points SPL peak and the optimal treatment was finally confirmed. The results showed that noise reduction measures can generally decrease the SPL peak around the crew.

A numerical model of carrier saturation velocity and drain current for the monolayer graphene field effect transistors (GFETs) is proposed by considering the exponential distribution of potential fluctuations in disordered graphene system. The carrier saturation velocity of GFET is investigated by the two-region model, and it is found to be affected not only by the carrier density, but also by the graphene disorder. The numerical solutions of the carrier density and carrier saturation velocity in the disordered GFETs yield clear and physical-based results. The simulated results of the drain current model show good consistency with the reported experimental data.

Understanding the effect of process parameters on microstructure is crucial to control or optimize microstructure for laser direct deposition process. Four thin-wall samples of TC11 titanium alloy are deposited with different process parameters. They showed different macro/micro-structure and mechanical properties. The reason is analyzed by temperature field of samples which are simulated by ANSYS software. Results show that, deposition with low laser power and slow scanning speed is conducive to reducing molten pool temperature and soaking time in β-phase region, refining original β grain and improving the plastic properties of the deposited parts. Deposition with high laser power and rapid scanning speed, combined with interlayer stay, is helpful to increase the cooling rate within α+β phase region, refine intragranular α lamellar and improve the tensile strength of deposited parts.

Powder transport ratio is defined as the mass ratio of powder particles fed into the molten pool to all powders transported in the process of laser cladding by lateral powder feeding. According to the law of mass conservation and kinematic equation in physics, a powder transport model for flow field with cylindrical distribution and a mathematical expression of powder transport ratio are proposed. For different process parameters, the cross-sectional area of the clad layer is calculated by the model. Theoretical and experimental results are compared. The variation tendency of the theoretical cross-sectional area agrees well with the experimental results. The results indicate that the powder transport model can be used for fundamental research of real powder flow field.

In a deformation progress of a polyvinyl chloride sheet, the coupled deforming heat is recorded by a thermal infrared imager. In order to have a real-time study for the variation regularity of the deforming temperature field distribution, all infrared images are imported into MATLAB software as digital data through a dynamic link routine compiled based on MATLAB and Windows. By utilizing a gradient-based transition region extraction algorithm and an interpolation algorithm, the high-resolution recognized and reconstructed infrared images are obtained from original blurring images recorded in thermal infrared imager. The variations of temperature distribution are studied combining with the test data based on MATLAB.

Hub nodes of urban traffic complex network are very important for region traffic signal control. Traditionally, region traffic signal control system like SCOOT/SCATS use traffic flow, vehicle queue and distance between junctions as reference in sub-control-area selection practice, in which process engineers’ experience should play importance roles. In this paper, node degree, node betweeness and high peak hour traffic flow are selected as indexes for traffic network node importance assessment. Moreover, C-Means clustering is applied to analysis which junction could be act as a hub node for regional traffic control. To test the effectiveness of this method, urban network around Chang’an Street in Beijing including almost fifty nodes, China is used as trail field. Data result shows Changchunjie, FuyoujieNankou and Hepingmen junction have high clustering characteristics when clustering number are 3, 4 and 5. And the clustering center shows very similar prosperities with real hub node in practice. In conclusion, the multi-index and clustering analysis could provide theoretical support for urban traffic complex network hub node assessment.

Due to the promising properties of high entropy alloy, TiVCrAlSi high entropy alloy coating was prepared on Ti-6Al-4V alloy surface by laser cladding. The microstructure and phase analysis of as-cast TiVCrAlSi alloy and laser clad coating were characterized by scanning electron microscope and X-ray diffraction. The results indicate that as-cast TiVCrAlSi alloy is mainly composed of (Ti,V)5Si3 and bcc phase. The laser clad coating is metallurgically bonded to the substrate with few pores and cracks. Laser clad TiVCrAlSi coating is also composed of (Ti,V)5Si3 and bcc phases.

Purpose Kashin-Beck disease (KBD) is an osteoarthropathy affecting 2.5 million of 30 million residents of China's KBD-endemic regions. This study assesses the etiologic role of river water as a main source of drinking water, its impact on and interaction with KBD familial aggregation. Methods From 2006–2007, we conducted a population-based case-control study of familial KBD in Linyou County, Shaanxi Province, China. Study subjects included 212 case families (1,951 individuals) and 212 control families (1,897 individuals). Using conditional logistic regression to analyze case-control data and second-order generalized estimating equation (GEE2) to examine family data, we adjusted for age and gender in all marginal regression analyses. Results The odds ratio (OR) for river water intake's association with KBD was 5.97 (95% confidence interval [CI]), 3.32–10.72). Compared with relatives of controls, proband relatives had a higher risk of disease, with a conditional OR = 2.35 (95% CI, 1.05–5.24). When river water was controlled in the analyses, association parameters among first- and second-degree relatives were no longer statistically significant. Conclusion Collective river water intake among relatives was likely and predominantly responsible for familial KBD aggregation in southwestern China.

The total load on a crank bearing was calculated by performing a load analysis of the crank connecting rod mechanism. The Reynolds equation for hydrodynamic lubrication of the crank bearing was established at the Reynolds boundary condition and was then solved using the Holland method. From this the regular track of the bearing axis was obtained. As the crank bearing gradually wears the eccentricity ratio corresponding to the minimum oil film thickness increases gradually. The oil-bound film eventually breaks down, which allows friction and collision between the metal surfaces of the crank pin and the bearing. The rigid impact leads to excitation of high frequency vibrations at the natural frequencies of the connecting rod. The experiments show that the wear condition of the crank bearing can be identified correctly through the vibration signature at the natural frequencies of the connecting rod. The degree of wear can be predicted accurately through the energy content of the high frequency bands.

The behavior of mitochondria during early oogenesis remains largely unknown in zebrafish. We used three mitochondrial probes (Mito Tracker Red CMXRos, Mito Tracker Green FM, and JC-1) to stain early zebrafish oocyte mitochondria, and confocal microscopy to analyze mitochondrial aggregation and distribution. By using fluorescence recovery after photobleaching (FRAP), we traced mitochondrial movement. The microtubule assembly inhibitor nocodazole and microfilament inhibitor cytochalasin B (CB) were used to analyze the role of microtubules and microfilaments on mitochondrial movement. By using the dual emission probe, JC-1, and oxidative phosphorylation uncoupler, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP), we determined the distribution of active and inactive (low-active) mitochondria. Green/red fluorescence ratios of different sublocations in different oocyte groups stained by JC-1 were detected in merged (green and red) images. Our results showed that mitochondria exhibited a unique distribution pattern in early zebrafish oocytes. They tended to aggregate into large clusters in early stage I oocytes, but in a threadlike state in latter stage I oocytes. We detected a lower density mitochondrial area and a higher density mitochondrial area on opposite sides of the germinal vesicle. The green/red fluorescence ratios in different sublocations in normal oocytes were about 1:1. This implies that active mitochondria were distributed in all sublocations. FCCP treatment caused significant increases in the ratios. CB and nocodazole treatment caused an increase of the ratios in clusters and mitochondrial cloud, but not in dispersed areas. Mitochondria in different sublocations underwent fast dynamic movement. Inhibition or disruption of microtubules or microfilaments resulted in even faster mitochondrial free movement.

Heterochromatin protein 1 (HP1) is closely associated with diverse chromatin organization and function in mitosis. However, we almost know nothing about HP1 in mammalian oocyte. Here, we investigated the subcellular distribution of HP1alpha and its spatial relationship to histone modifications during mouse oocyte maturation. Dynamic migration of HP1alpha was observed in germinal vesicle with non-surrounded nucleolus (NSN) to surrounded nucleolus (SN) oocytes, which may be essential for the transition of chromatin conformation during the development of antral oocytes. In meiosis, HP1alpha was clearly detectable at the periphery of chromosomes from pre-metaphase I stage to anaphase-telophase I stage. Spatial correlation between HP1alpha and histone modifications is highly variable around the time of meiotic resumption. In germinal vesicle oocytes, HP1alpha almost colocalized with all histone modifications examined in this study except for phosphorylation of serine 28 on histone H3. However, with the breakdown of germinal vesicle, HP1alpha was detected mostly in the chromosomal domains with strong phosphorylation of serine 10 and 28 on histone H3, and they also partially associated with methylated histones. These results presented the functional implication of histone modifications in the regulation of HP1alpha during oocyte maturation. In addition, we also showed that blocking the function of HP1alpha by microinjecting anti-HP1alpha antibody caused the delay of GVBD, however, this effect may not be achieved through modifying histones.

Support Vector Machines (SVM) is a new general machine-learning tool based on structural risk minimization principle. This characteristic is very signific ant for the fault diagnostics when the number of fault samples is limited. Considering that SVM theory is originally designed for a two-class classification, a hybrid SVM scheme is proposed for multi-fault classification of rotating machinery in our paper. Two SVM strategies, 1-v-1 (one versus one) and 1-v-r (one versus rest), are respectively adopted at different classification levels. At the parallel classification level, using 1-v-1 strategy, the fault features extracted by various signal analysis methods are transferred into the multiple parallel SVM and the local classification results are obtained. At the serial classification level, these local results values are fused by one serial SVM based on 1-v-r strategy. The hybrid SVM scheme introduced in our paper not only generalizes the performance of signal binary SVMs but improves the precision and reliability of the fault classification results. The actually testing results show the availability suitability of this new method.

In animal mitochondrial DNA inheritance, it remains largely unclear where the mitochondrial genetic bottleneck localizes and how it works in rewinding Muller’s ratchet. In a variety of different animals germ plasm mRNAs typically aggregate along with numerous mitochondria to form the mitochondrial cloud (MC) during oogenesis. The MC has been found to serve as messenger transport organizer for germ plasm mRNAs. Germ plasm RNAs in MC will specifically distribute to the primordial germ cells of the future embryo. It has been proposed that the MC might be the site where selected mitochondria accumulate for specific transmission to grandchildren but this idea received relatively little attention and the criterion by which mitochondria are selected remains unknown. Our recent results in zebrafish provided further evidence for selective mitochondria accumulation in the MC by showing that mitochondria with high-inner membrane potential tend to be recruited preferentially into the MC, and these mitochondria are transported along with germ plasm to the cortex of the vegetal pole. By analyzing the composition, behavior and functions of the MC, and in reviewing related literature, we found strong support for the proposition that the MC corresponds to the position and function of the mitochondrial genetic bottleneck.

To explore the family aggregation and the role of hereditary factors in the pathogenesis of Kashin-Beck disease (KBD).With a stratified sampling method, the general population of 14 villages of Linyou County were studied, from whom 225 KBD probands were selected using systematic sampling at the rate of (1/2). A total of 304 siblings of the probands were ascertained, and in these sibling pairs, the segregation ratio, heritability in different age groups and weighted mean heritability of the siblings were estimated using the methods of Li-Mantel-Grart and Falconer.The KBD distribution scope in the KBD families exceeded the scope of binomial distribution (P0.001), suggesting obvious family aggregation. The prevalence rate in the siblings of the KBD pedigree was 19.41% (59/304), significantly higher than that in the 14 KBD villages [10.90% (1180/10823), chi2=21.62, P0.001]. The segregation ratio and heritability in the siblings of the KBD pedigrees were 0.061 and 28.61%, respectively.As a polygenetic inheritance disease, KBD exhibits obvious familial aggregation, and genetic susceptibility accounts for (1/4) of the risk factors for KBD.

The behavior of mitochondria during early oogenesis remains largely unknown in zebrafish. We used three mitochondrial probes (Mito Tracker Red CMXRos, Mito Tracker Green FM, and JC-1) to stain early zebrafish oocyte mitochondria, and confocal microscopy to analyze mitochondrial aggregation and distribution. By using fluorescence recovery after photobleaching (FRAP), we traced mitochondrial movement. The microtubule assembly inhibitor nocodazole and microfilament inhibitor cytochalasin B (CB) were used to analyze the role of microtubules and microfilaments on mitochondrial movement. By using the dual emission probe, JC-1, and oxidative phosphorylation uncoupler, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP), we determined the distribution of active and inactive (low-active) mitochondria. Green/red fluorescence ratios of different sublocations in different oocyte groups stained by JC-1 were detected in merged (green and red) images. Our results showed that mitochondria exhibited a unique distribution pattern in early zebrafish oocytes. They tended to aggregate into large clusters in early stage I oocytes, but in a threadlike state in latter stage I oocytes. We detected a lower density mitochondrial area and a higher density mitochondrial area on opposite sides of the germinal vesicle. The green/red fluorescence ratios in different sublocations in normal oocytes were about 1:1. This implies that active mitochondria were distributed in all sublocations. FCCP treatment caused significant increases in the ratios. CB and nocodazole treatment caused an increase of the ratios in clusters and mitochondrial cloud, but not in dispersed areas. Mitochondria in different sublocations underwent fast dynamic movement. Inhibition or disruption of microtubules or microfilaments resulted in even faster mitochondrial free movement.

The changes in histone acetylation are not always consistent in various cell types and at different developmental stages. We immunostained specific antibodies against acetylated lysine 9 of histone H3 and acetylated lysines 5 and 12 of histone H4 in an effort to understand the detailed changes in histone acetylation during sheep oocyte meiosis. We found that the acetylation fluorescence signals of H3/K9 and H4/K12 on chromatin appeared intensively in the germinal vesicle (GV), late-GV (L-GV), and germinal vesicle breakdown (GVBD) stages and became weak in metaphase I (MI); however staining reappeared in anaphase I-telophase-I (AI-TI) and metaphase II (MII). Furthermore, staining was detected in the first polar bodies. The fluorescence signals of H4/K5 first appeared in the MI stage and became intensive in the AI-TI stage; however they were barely detectable in MII stage chromosomes and first polar bodies. We conclude that the acetylation patterns of H3/K9 and H4/K12 during oocyte meiotic maturation are similar and that the pattern of H4/K5 is unique.

As a new general machine-learning tool based on structural risk minimization principle, Support Vector Machines (SVM) has the advantageous characteristic of good generalization. For this reason, the application of SVM in fault diagnosis field has becomes one growing reach focus. In this paper, data fusion strategy based on multi-class SVMs is proposed to diagnose the gear fault. The fault features extracted from vibration signals with various analysis methods are transferred into the SVM in the feature fusion level. The signal analysis methods include Power Spectrum, Cepstrum, wavelet, etc. Data fusion improves the reliability of the diagnosis results. The SVM is originally designed for two-class classification. In order to satisfy the need of multi-fault classification, one three-class SVMs is built to combine the outputs of the feature fusion levels and to classify the four fault states of the gear. The actually diagnosis results show that the fault classification performance of the multi-class SVMs is evidently powerful and precise.

The naturally infected scallops Chlamys farreri sampled during mass mortality in summer of 2003 was detected by means of histopathological and MAb-based immunofluorescence assay (IFA). The results of histological examination demonstrated that a series of histopathological changes including cell swelling, basophilic increase, disorder, partial sloughing and excessive sloughing were always observed in epithelia of many different organs, e.g. mantle, gills, stomach, intestine and kidney. Additionally, the infected tissues were applied for in situ detection of the "acute virus necrobiotic disease" (AVND) virus by means of specific MAb-based IFA, and the result demonstrated that this pathological changes or lesions were perfectly coincident with the positive cells (fluorescencing cells) . The positive cells were denser in some local area of epithelia, and exhibited serious pathological lesions, which would reveal the roles of this virus in pathogenesis and further confirm that the AVND virus is the main causative agent of mass mortalities among cultured scallop Chlamys farreri farmed in northern coast of China.

To study the chemical constituents of the pine needles of Pinus massoniana lamb..Various chromatographic techniques were used to separate and purify. Their physico-chemical properties and spectral data (UV, IR, MS, 1H-1 H COSY, HMQC, DEPT, HMBC and ORD ect.) were measured for structure elucication.Three compounds were isolated from the n-BuOH fraction of water-extracts. Their structures were identified as massonianoside A (4), massonianoside A: (7S, 8R)-3, 4, 9'-trihydroxyl-3-methyoxyl-7, 8-dihydrobenzofunan-1'-propanolneoligan-9-O-alpha-L-rhamnopyranoside, massonianoside C (5), (7S, 8R)-9,9'-dihydroxyl-3,3'-dimethyoxyl-7,8-dihydrobenzofunan-1'- propanolneoligan-4-O-alpha-L-rhamnopyranoside and cedrusin-4-O-beta-glucoside (6), (7S, 8R)-3',9,9'-trihydroxyl-3-methoxyl-7,8-dihydrobenzofunan-1'- propanolneoligan-4-O-beta-D-glucopyranoside.Compound 4 and 5 are new compounds.