84 results on '"YUAN, Q."'
Search Results
2. The Discharge Characteristics of Capacitively Coupled Ar Plasma as the Change of Pressure.
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Yin, G. Q., Wang, J. J., and Yuan, Q. H.
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PLASMA pressure ,ELECTRON density ,ARGON plasmas ,ELECTRON distribution ,ELECTRON temperature ,HIGH-frequency discharges ,GLOW discharges - Abstract
The discharge characteristics of coupled capacitively argon plasmas with change of pressure are studied. The mean electron temperature and electron density are calculated via Ar spectral lines at different pressures (10–80 mTorr) and at four frequencies (13.56, 40.68, 94.92, and 100 MHz). From 10–30 mTorr, the mean electron temperature and the electron density both decrease with the increase of pressure at certain frequency. From 30–80 mTorr, the mean electron temperature similarly first increase then decrease with pressure at 94.92 and 100 MHz, and decrease at 40.68 MHz and increase at 13.56 MHz with pressure. The largest mean electron temperature is found at 40.68 MHz. From 40–80 mTorr, the electron density both increase at 94.92 and 100 MHz. The electron density change little at 40.68 and 13.56 MHz with pressure increase. Particle-in-cell/Monte Carlo collisions (PIC/MCC) method developed within the Vsim 8.0 simulation package is used to simulate the electron density, the potential distribution and the electron energy probability function (EEPF) under the experimental condition. Sheath width decrease with the pressure increase. The EEPF of 40.68 MHz is bi-Maxwellian and 100 MHz are nearly Maxwellian with a large population of low-energy electrons with the increase of pressure. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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3. Infrared Radiation Characteristics During Crack Development in Water-Bearing Sandstone.
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Cao, K., Yuan, Q., Xie, G., and Shi, Y.
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INFRARED radiation , *SANDSTONE , *ROCK deformation , *STATISTICAL correlation - Abstract
We studied the infrared radiation (IR) characteristics of sandstone cracks with different water contents. We propose a new IR-based method to distinguish the initial development and damage point of cracks. The maximum variation of IR variance shows a quadratic relationship with water content. By defining crack initiation and damage using a stiffness stress curve, it can be concluded that the crack initiation and crack damage IR variance thresholds show a quadratic relationship with water content. The proportion of the two thresholds at the maximum IR variation amplitude does not change with increasing water content, yielding ratios of 47.51% and 78.19% for crack initiation and crack damage, respectively. The rock stress threshold of crack initiation and damage show a negative logarithmic relationship with their respective IR variance thresholds with correlation coefficients above 0.90. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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4. Senescent thyroid tumor cells promote their migration by inducing the polarization of M2-like macrophages.
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Zhang, C., Gu, X., Pan, M., Yuan, Q., and Cheng, H.
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Purpose: An in-depth understanding of the mechanism of thyroid cancer progression will help identify patients with thyroid cancer with a high risk of recurrence and metastasis. Although studies have pointed out that the senescence of thyroid tumor cells may stimulate TAMs and cause a series of changes. However, the role of TAMs in aging thyroid cancer cells is still unknown. The aim of this study was to investigate the function of TAMs in aging thyroid cancer cells. Methods: We conducted in vitro model studies based on the K1 cell line to induce tumor cell senescence and study its effect on the differentiation of macrophages, flow cytometry was used to confirm polarization of macrophages, transwell assay was used to confirm changes of invasion and migration of tumor cells. Result: Our data indicate that aging thyroid tumor cell lines trigger the polarization of M2-like macrophages, accompanied by increased expression of CCL17, CCL18, IL-18, and TGFβ1. This event is caused by the activation of the NFκB pathway upregulation of CXCL2 and CXCL3 is related. Further studies have shown that differentiated M2-like macrophages promote tumor cell migration (but have no effect on cell proliferation). Conclusion: Our study indicating that the interaction between tumor and TAMs also occurs in the advanced stages of thyroid tumors and will lead to faster tumors progress. [ABSTRACT FROM AUTHOR]
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- 2021
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5. Numerical investigation on the effect of upstream ramps on film cooling performance with compound angles.
- Author
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Zheng, D., Wang, X., and Yuan, Q.
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This paper presents a numerical investigation on the concept for improving film cooling performance by placing a ramp upstream the film hole with compound angle. Eight cases with different geometry models are investigated, including the compound angles of 15°, 30°, 45° and the distances between the upstream ramps and film holes (upstream distances) of 5 mm, 10 mm, and 15 mm. The effect of compound angle and upstream distance on film cooling performance is studied. The cases of film cooling on a flat plate, film cooling with compound angle, and film cooling with an upstream ramp are also presented as a contrast. The film cooling performance is evaluated at the density ratio of 0.97 with the blowing ratios ranging from 1.0 to 2.0. Results obtained show that the film cooling performance with compound angle is greatly improved by the upstream ramp, especially in the region downstream the film hole. Both the entrainment of coolant and modified kidney vortices are observed in the case of the novel geometry. The film cooling performance is greatly improved by the dual effect of coolant entrainment and modified kidney vortices. In addition, the film cooling performance is influenced by compound angle and upstream distance. With the increase of compound angle, the lateral adiabatic cooling effectiveness rises. With the increase of the upstream distance, the lateral adiabatic cooling effectiveness goes down. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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6. Effect of substrate-to-inoculum ratio on anaerobic digestion of treated and untreated cotton textile waste.
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Juanga-Labayen, J., Yanac, K., and Yuan, Q.
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Anaerobic digestion is a promising technology for biogas recovery from cotton textile waste. However, limited studies have focused on anaerobic digestion of cotton textile waste. This study evaluated the effect of different SIRs of 0.5, 1.0, 1.5, and 2.0 using treated and untreated cotton substrate in a batch anaerobic digestion process under mesophilic condition for 15 days. The cotton textile waste was treated with 0.5 M Na
2 CO3 at 150 °C for 3 h. The highest methane yield of 366.76 mL/g VS, which is equivalent to anaerobic degradability of 89.67%, was observed from SIR of 0.5 for untreated substrate. However, for treated substrate, SIR of 1.0, 1.5, and 2.0 shows an increased methane yield and anaerobic degradability of more than 50% when compared to untreated substrate. Furthermore, for treated substrate, higher substrate loading of SIR 1.0 produced a comparable yield of 306.73 mL CH4 /g VS, which is equivalent to anaerobic degradability of 75%. The Gompertz model fitted with the experimental data with R2 value of 0.96-0.99, which was an improvement over the first-order kinetic model. [ABSTRACT FROM AUTHOR]- Published
- 2021
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7. Local responses in 2D assemblies of elliptical rods when subjected to biaxial shearing.
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Yuan, Q., Li, Z., Gao, Y., Wang, Y. H., and Li, X.
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FUNCTIONALS , *ANISOTROPY - Abstract
This study explored the characteristics of local responses in 2D assemblies of elliptical particles when subjected to shearing. A biaxial shearing system was designed for this investigation, and two assemblies of elliptical rods with different eccentricities were used. To quantify the local responses, the assemblies were partitioned into individual Set Voronoi cells, and in this partition, the scaling method was proposed to tackle the interparticle overlapping problem. Then, in the Voronoi cells, the local strain was measured, accounting for the effect of interparticle rotation, and the local structures in terms of the local volume and anisotropy were estimated using Minkowski functionals. In the two samples, discontinuity by shearing was observed for these local quantities. Before the peak stress, the local strain developed randomly and the local volume followed a k-gamma distribution. After shearing, shear band and a mixed k-gamma distribution of the local volume emerged. For the local anisotropy, the variation inside shear band was significantly increased by shearing. Finally, the responses inside and outside the shear band were taken out separately for analysis, and the free-volume model was used to explain the differences between these two regions. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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8. Development of model equation for estimating the turbidity reduction in sediment-laden stormwater by a synthetic fiber fence.
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Yuan, Q. and Kim, Y.
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In this paper, a model equation for predicting the reduction efficiency of turbidity matters in a synthetic fiber fence was presented. This model is developed on the assumption that the collection efficiency of a single collector is contributed by three individual transport mechanisms including diffusion, interception and sedimentation. In consideration of the complex internal structure of fiber media, the simulation was also conducted in Happel's sphere-in-cell porous media model. In the process of modeling work, the dimensionless parameters governing particle deposition were calculated based on the operational and theoretical parameters, and the equation was subsequently obtained by multiple linear regression. The predicted removal efficacy is in a good agreement with the experimental data over a broad range of values using developed equations, indicating that the resulting equation was applicable to the high-speed filtration condition and highly porous filter media. Hence, the developed model may serve as an alternative for the development of turbid runoff treatment technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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9. Co-treatment of sewage sludge and mature landfill leachate by anaerobic digestion.
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Berenjkar, P., Islam, M., and Yuan, Q.
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In this study, sewage sludge was co-digested with different amounts of mature landfill leachate (0, 5, 10, 20, and 40% v/v) to evaluate the yield capacities of biogas and CH
4 . The highest biogas yield was obtained from the treatment with 10% leachate dose (T2) and control with 0% leachate dose, while the lowest biogas was produced from the treatment with 40% leachate dose. The highest CH4 production (maximum yield per kg VS consumed) was also obtained from T2, which was about 36% (v/v) higher than the control. This result was confirmed by the first-order kinetic model. It was also observed that the COD, TS, and VS removal efficiencies significantly decreased with increasing the leachate dose. However, the increased dose of leachate did not inhibit TN removal efficiency. This study demonstrates that mature landfill leachate could be treated via anaerobic co-digestion process with sewage sludge to enhance biogas production at low doses (up to 20% v/v). [ABSTRACT FROM AUTHOR]- Published
- 2019
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10. Numerical investigation on the effect of vortex generator shapes on film cooling performance.
- Author
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Zheng, D., Wang, X., and Yuan, Q.
- Abstract
This paper presents a numerical investigation on the concept for enhancing film cooling performance by placing shaped vortex generators (VG) upstream of the film hole. Nine cases with different shapes of vortex generators are investigated, including the rectangular shape, triangular shape, parallelogram shape, and trapezoid shape. The film cooling performance is evaluated at the density of 0.97 with the blowing ratios ranging from 0.5 to 1.5. Results obtained show that the film cooling performance is greatly improved by the upstream VG. The twisted flow rotates in the opposite direction of kidney vortices, attenuating its effect. Furthermore, the case with rectangular VG shows the most uniform coolant layer in the spanwise direction and the highest averaged adiabatic cooling effectiveness while the total pressure loss increases a bit as a penalty. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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11. Biological leachate treatment using anaerobic/aerobic process: suspended growth-activated sludge versus aerobic granular sludge.
- Author
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Ren, Y., M. Ferraz, F., and Yuan, Q.
- Abstract
Landfill leachate treatment was investigated using two anaerobic/aerobic sequencing batch reactors inoculated with suspended growth-activated sludge (ASBR) and aerobic granular sludge (GSBR). The total ammonium nitrogen (TAN) concentration in the GSBR influent was as high as 1200 mg/L with an average TAN removal efficiency of 99.7%. However, the ASBR treatment did not show a consistent performance in TAN removal. The TAN removal efficiency decreased with increasing ammonium concentration in the influent. Aerobic granular sludge was found to be more resistant to free ammonia (FA). In the GSBR, nitrification was partially inhibited at FA concentration from 48 to 57 mg/L, which was two times more than the FA concentration that inhibited nitrification in the ASBR. Low chemical oxygen demand removal efficiencies were obtained in both reactors, which was associated with the refractory organic content of the leachate used in this study. This resulted in poor phosphorous removal in both treatments. The results prove that aerobic granular sludge is a robust method as compared to suspended-activated sludge to treat leachate containing high levels of TAN and FA. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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12. Impact of pioglitazone on bone mineral density and bone marrow fat content.
- Author
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Pop, L., Lingvay, I., Yuan, Q., Li, X., Adams-Huet, B., and Maalouf, N.
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PIOGLITAZONE ,BONE marrow ,PLACEBOS ,BONE density ,RANDOMIZED controlled trials ,THERAPEUTICS - Abstract
Summary: Pioglitazone use is associated with an increased risk of fractures. In this randomized, placebo-controlled study, pioglitazone use for 12 months was associated with a significant increase in bone marrow fat content at the femoral neck, accompanied by a significant decrease in total hip bone mineral density. The change in bone marrow fat with pioglitazone use was predominantly observed in female vs. male participants. Introduction: Use of the insulin sensitizer pioglitazone is associated with greater fracture incidence, although the underlying mechanisms are incompletely understood. This study aimed to assess the effect of pioglitazone treatment on femoral neck bone marrow (BM) fat content and on bone mineral density (BMD), and to establish if any correlation exists between the changes in these parameters. Methods: In this double-blind placebo-controlled clinical trial, 42 obese volunteers with metabolic syndrome were randomized to pioglitazone (45 mg/day) or matching placebo for 1 year. The following measurements were conducted at baseline and during the treatment: liver, pancreas, and femoral neck BM fat content (by magnetic resonance spectroscopy), BMD by DXA, abdominal subcutaneous and visceral fat, and beta-cell function and insulin sensitivity. Results: Results were available for 37 subjects who completed the baseline and 1-year evaluations. At 12 months, BM fat increased with pioglitazone (absolute change, +4.1%, p = 0.03), whereas BM fat content in the placebo group decreased non-significantly (−3.1%, p = 0.08) ( p = 0.007 for the pioglitazone-placebo response difference). Total hip BMD declined in the pioglitazone group (−1.4%) and increased by 0.8% in the placebo group ( p = 0.03 between groups). The change in total hip BMD was inversely and significantly correlated with the change in BM fat content (Spearman rho = −0.56, p = 0.01) in the pioglitazone group, but not within the placebo group (rho = −0.29, p = 0.24). Changes in BM fat with pioglitazone were predominantly observed in female vs. male subjects. Conclusions: Pioglitazone use for 12 months compared with placebo is associated with significant increase in BM fat content at the femoral neck, accompanied by a small but significant decrease in total hip BMD. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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13. A Study of Growth of Austenite Grains in a Steel Microalloyed with Ti and Nb.
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Yang, H., Xu, G., Wang, L., Yuan, Q., and He, B.
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AUSTENITE ,STEEL alloys ,NIOBIUM ,TITANIUM ,TRANSMISSION electron microscopes ,MICROSTRUCTURE - Abstract
The growth of austenite grains and the dissolution of carbonitrides under heating of a structural steel microalloyed with niobium and titanium are studied. The microstructure of the steel is investigated with the help of light and transmission electron microscopes. The content of elements in precipitated particles is determined using an energy dispersive spectrometer. The kinetic equation of grain growth is derived and the critical temperature above which the carbonitrides stop to hinder grain growth is determined. Recommendations are given on the temperature modes of hot rolling. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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14. Simulation of interactions among multiple debris flows.
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Chen, H., Zhang, L., Gao, L., Yuan, Q., Lu, T., Xiang, B., and Zhuang, W.
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LANDSLIDE hazard analysis ,SLOPE stability ,DYNAMIC viscosity ,RAINFALL ,WENCHUAN Earthquake, China, 2008 - Abstract
Adjacent debris flows may interact in many ways: two or more concurrent debris flows may merge; one debris flow can run out over an existing debris flow fan. Such interactions may cause debris flow properties to change in the mixing process as well as more severe adverse effects than those caused by a single debris flow. This paper aims to investigate the interactions among channelized debris flows originated from adjacent catchments. Both concurrent and successive debris flows are considered. If several debris flows originate from different locations concurrently and merge, the volumetric sediment concentration (i.e., the ratio of the volume of solid material to the total volume of debris flow), C , is a good index to capture the mixing process of these debris flows. The change in C reflects where mixing occurs and the mixing degree. The debris flow properties (e.g., yield stress and dynamic viscosity) evolve in the mixing process and can be captured by the change in C . The debris flow with a larger volume dominates the mixing process, and the properties of the mixed debris flow are more similar to those of the larger debris flow. The inundated areas and runout distances of successive debris flows are smaller than those of concurrent debris flows of the same total volume due to the smaller scales of the individual events and blockage by the earlier debris flows. However, the deposit depth in the interacting part of the debris flow fans of successive debris flows can be much larger than that of concurrent debris flows, leading to more destructive cascading hazards (e.g., the formation of debris barrier lakes). The sequence of successive debris flows not only significantly influences the runout characteristics of the debris flows but also substantially affects the cascading hazards. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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15. Low regulatory T cell and high IL-17 mRNA expression in a mouse Graves' disease model.
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Yuan, Q., Zhao, Y., Zhu, X., and Liu, X.
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- 2017
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16. Correlation between residual speedometer needle reading and impact speed of vehicles in traffic accidents.
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Yuan, Q., Li, Y., Xing, S., and Lv, Y.
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TRAFFIC accidents , *SPEEDOMETERS , *TRANSPORTATION , *TRAFFIC conflicts , *ROADS - Abstract
In actual traffic accidents, a phenomenon is observed where the speedometer needle jams at a certain value after the impact. Using the residual reading of the speedometer, we may infer the approximate vehicle speed while the impact occurred. Based on the function of typical speedometer, the impact characteristic and damage mechanism of vehicles, this paper describes the research of how the speedometer needle stops during accidents and its failure modes. According to the statistics of thirty specific traffic accident cases containing residual speedometer needle readings, we obtain and summarize the characteristics and rules concerning the accidents and the related information. Furthermore, a typical accident case is analyzed by in-depth level. The results reveal that for the accident vehicles with electronic speedometers, there is a strong correlation between the residual reading of the speedometer and the real vehicle impact speed. The conclusions may provide a new effective method and reference for accident reconstruction and the estimation of vehicle speed. [ABSTRACT FROM AUTHOR]
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- 2015
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17. THE WITNESS SET OF COEXISTENCE OF QUANTUM EFFECTS AND ITS PRESERVERS.
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HE, K., SUN, F. G., HOU, J., and YUAN, Q.
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QUANTUM theory ,ISOMORPHISM (Mathematics) ,MATRICES (Mathematics) ,LINEAR algebra - Abstract
One of unsolved problems in quantum measurement theory is to characterize coexistence of quantum effects. In this paper, applying positive operator matrix theory, we give a mathematical characterization of the witness set of coexistence of quantum effects and obtain a series of properties of coexistence. We also devote to characterizing bijective morphisms on quantum effects leaving the witness set invariant. Furthermore, applying linear maps preserving commutativity, which are characterized by Choi, Jafarian and Radjavi [Linear maps preserving commutativity, Linear Algebra Appl. 87 (1987), 227--241.], we classify multiplicative general morphisms leaving the witness set invariant on finite dimensional Hilbert space effect algebras. [ABSTRACT FROM AUTHOR]
- Published
- 2015
18. A multiplex ELISA-based protein array for screening diagnostic antigens and diagnosis of Flaviviridae infection.
- Author
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Wang, D., Zheng, Y., Kang, X., Zhang, X., Li, L., Yuan, Q., Yang, Y., Jiang, Y., Jiang, H., Hao, H., Chen, W., Liu, L., Li, X., and Chen, F.
- Subjects
FLAVIVIRUSES ,PROTEIN microarrays ,ENZYME-linked immunosorbent assay ,INFECTION ,ANTIGENS ,DENGUE viruses ,DIAGNOSIS - Abstract
Assays with the ability to detect multiple antibodies in parallel have a wide range of potential applications in epidemiologic research. Here, a multiplex enzyme-linked immunosorbent assay-based protein array (ELISA-array) was developed to simultaneously detect five Flaviviridae infections. The platform was based on an indirect ELISA and 15 antigens were constructed for specific antibody detection against five Flaviviridae viruses (Japanese B, tick-borne encephalitis, West Nile, dengue, and yellow fever viruses) and four serotypes of dengue virus. The specificity was evaluated by calculating the signal value cross-reacting with serum immunized with other viruses, and the sensitivity of antigens was compared with conventional ELISAs using immunized rabbit polyclonal antisera. IgG and IgM calibration curves were constructed to evaluate the reproducibility of the platform. Finally, 24 dengue fever (DF) infection and 15 tick-borne encephalitis (TBE) infection clinical sera were used to compare the advantage of ELISA-array to ELISA. After initial screening, 9 out of 15 antigens were chosen for ELISA-array printing. By using different virus-immunized rabbit antiserum, 7 out of 9 antigens showed good specificity in the ELISA-array. Eight out of 9 antigens showed four-fold greater sensitivity in ELISA-array compared to that in conventional ELISAs. The coefficients of determination ( r) close to 1 showed high reproducibility, and clinical sera test showed that ELISA-array had higher specificity and sensitivity than traditional ELISA. ELISA-array was a good platform for antigen screening and this multiplexed assay might be a useful and convenient tool for multiple immunological detection of infectious viral antibodies. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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19. Effect of estrogen deficiency on the fixation of titanium implants in chronic kidney disease mice.
- Author
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Zhang, S., Guo, Y., Zou, H., Sun, N., Zhao, D., Liu, W., Dong, Y., Cheng, G., and Yuan, Q.
- Subjects
ACADEMIC medical centers ,ANALYSIS of variance ,ANIMAL experimentation ,CHRONIC kidney failure ,ESTROGEN ,MICE ,RESEARCH funding ,STATISTICS ,T-test (Statistics) ,TITANIUM ,OSSEOINTEGRATION ,DATA analysis - Abstract
Summary: We established a chronic kidney disease (CKD) mouse model with estrogen deficiency and inserted titanium implants into the femur of such mice to investigate the fixation of the implants. Both the histomorphometry and implant resistance indicated that estrogen deficiency impaired the fixation of titanium implants inserted into such mice. Introduction: CKD has been regarded as a worldwide public health problem. Estrogen is a critical factor for both renal protection and bone remodeling. A previous study demonstrated that CKD impairs the early healing of titanium implants. However, the combined effect of estrogen deficiency and CKD on the fixation of titanium implants is largely unknown. Methods: Forty 9-week-old female C57BL mice were randomly divided into sham, ovariectomy (OVX), CKD, and CKD + OVX groups. Uremia and estrogen deficiency were induced by 5/6 nephrectomy and OVX, respectively. Experimental titanium implants were inserted into the distal end of the femur. Bone-implant contact (BIC) ratio and bone volume (BV/TV) around the implants were histomorphometrically analyzed. The fixation strength of the implant was measured by a biomechanical push-in resistance test. Results: Serum measurement confirmed a significant increase in serum blood urea nitrogen (BUN) in the CKD group, which was further increased by OVX. Estrogen deficiency led to significant decreases in the BIC ratio, BV/TV, and the push-in resistance in CKD animals. There was a significant interaction between the effects of OVX and CKD, with OVX exacerbating the effects of CKD on BIC ratio and push-in resistance. Conclusions: The results indicated that estrogen deficiency exerts a synergistic effect with CKD and further impairs the fixation of titanium implants in CKD mice. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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20. Do maternal opioids reduce neonatal regional brain volumes? A pilot study.
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Yuan, Q, Rubic, M, Seah, J, Rae, C, Wright, I M R, Kaltenbach, K, Feller, J M, Abdel-Latif, M E, Chu, C, and Oei, J L
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BRAIN anatomy , *LONGITUDINAL method , *MAGNETIC resonance imaging , *NARCOTICS , *SCIENTIFIC observation , *RESEARCH funding , *STATISTICS , *T-test (Statistics) , *PILOT projects , *DATA analysis , *DATA analysis software , *DESCRIPTIVE statistics , *MANN Whitney U Test , *MATERNAL exposure - Abstract
Objective:A substantial number of children exposed to gestational opioids have neurodevelopmental, behavioral and cognitive problems. Opioids are not neuroteratogens but whether they affect the developing brain in more subtle ways (for example, volume loss) is unclear. We aimed to determine the feasibility of using magnetic resonance imaging (MRI) to assess volumetric changes in healthy opioid-exposed infants.Study design:Observational pilot cohort study conducted in two maternity hospitals in New South Wales, Australia. Maternal history and neonatal urine and meconium screens were obtained to confirm drug exposure. Volumetric analysis of MRI scans was performed with the ITK-snap program.Result:Scans for 16 infants (mean (s.d.) gestational age: 40.9 (1.5) weeks, birth weight: 3022.5 (476.6) g, head circumference (HC): 33.7 (1.5 cm)) were analyzed. Six (37.5%) infants had HC <25th percentile. Fourteen mothers used methadone, four used buprenorphine and 11 used more than one opioid (including heroin, seven). All scans were structurally normal whole brain volumes (357.4 (63.8)) and basal ganglia (14.5 (3.5)) ml were significantly smaller than population means (425.4 (4.8), 17.1 (4.4) ml, respectively) but lateral ventricular volumes (3.5 (1.8) ml) were larger than population values (2.1(1.5)) ml.Conclusion:Our pilot study suggests that brain volumes of opioid-exposed babies may be smaller than population means and that specific regions, for example, basal ganglia, that are involved in neurotransmission, may be particularly affected. Larger studies including correlation with neurodevelopmental outcomes are warranted to substantiate this finding. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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21. Prediction of Transmembrane Proteins from Their Primary Sequence by Support Vector Machine Approach.
- Author
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De-Shuang Huang, Kang Li, Irwin, George William, Cai, C. Z., Yuan, Q. F., Xiao, H. G., Liu, X. H., Han, L. Y., and Chen, Y. Z.
- Abstract
Prediction of transmembrane (TM) proteins from their sequence facilitates functional study of genomes and the search of potential membrane-associated therapeutic targets. Computational methods for predicting TM sequences have been developed. These methods achieve high prediction accuracy for many TM proteins but some of these methods are less effective for specific class of TM proteins. Moreover, their performance has been tested by using a relatively small set of TM and non-membrane (NM) proteins. Thus it is useful to evaluate TM protein prediction methods by using a more diverse set of proteins and by testing their performance on specific classes of TM proteins. This work extensively evaluated the capability of support vector machine (SVM) classification systems for the prediction of TM proteins and those of several TM classes. These SVM systems were trained and tested by using 14962 TM and 12168 NM proteins from Pfam protein families. An independent set of 3389 TM and 6063 NM proteins from curated Pfam families were used to further evaluate the performance of these SVM systems. 90.1% and 86.7% of TM and NM proteins were correctly predicted respectively, which are comparable to those from other studies. The prediction accuracies for proteins of specific TM classes are 95.6%, 90.0%, 92.7% and 73.9% for G-protein coupled receptors, envelope proteins, outer membrane proteins, and transporters/channels respectively; and 98.1%, 99.5%, 86.4%, and 98.6% for non-G-protein coupled receptors, non-envelope proteins, non-outer membrane proteins, and non-transporters/non-channels respectively. Tested by using a significantly larger number and more diverse range of proteins than in previous studies, SVM systems appear to be capable of prediction of TM proteins and proteins of specific TM classes at accuracies comparable to those from previous studies. Our SVM systems - SVMProt, can be accessed at http://jing.cz3.nus.edu.sg/cgi-bin/svmprot.cgi. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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22. Miscible Displacements in Porous Media with Time-Dependent Injection Velocities.
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Yuan, Q. and Azaiez, J.
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POROUS materials ,GROWTH rate ,ANALYTICAL mechanics ,MISCIBLE displacement (Petroleum engineering) ,VELOCITY - Abstract
Miscible displacements in homogeneous porous media involving time-dependent injection velocities $$U(t)$$ are analyzed. The displacements consist of periodic cycles that involve alternating stages of injection and production or of injection and soaking. Results of a linear stability analysis revealed that the growth rate of disturbances follows the overall trends of the velocity $$U(t)$$ but with noticeable differences in periods of transition from production to injection. Furthermore, the growth rate of the time-dependent velocity was found to be smaller than that of a constant injection with a velocity equal to that corresponding to the minimum of $$U(t)$$ while an overshoot was observed with respect to a displacement with a constant injection velocity equal to the maximum of $$U(t)$$ . Nonlinear simulations revealed that the dynamics of the flow can be drastically changed from those of the corresponding constant injection velocity and the changes depend on the period of the cycles, the amplitude of the velocity and on whether the displacement is initiated through an injection or a soaking stage. The enhancement or attenuation of the instability in comparison with the constant injection velocity increases with the cycles' period and the amplitude of the velocity in the injection stage, with the effects of the former being more prominent. It was also found that, beyond a certain critical cycle period, it is possible to observe instability and fingering in the case of time-dependent displacements that actually result in a net zero flow. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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23. Tumour-initiating capacity is independent of epithelial-mesenchymal transition status in breast cancer cell lines.
- Author
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Xie, G, Ji, A, Yuan, Q, Jin, Z, Yuan, Y, Ren, C, Guo, Z, Yao, Q, Yang, K, Lin, X, and Chen, L
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CANCER research ,BREAST cancer ,CANCER cells ,EPITHELIAL cells ,MESENCHYME ,CYTOKINES ,CELL physiology - Abstract
Background:Epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) are considered to be crucial for cancer biology. The purpose of this study was to determine whether EMT directly led to the acquisition of tumour-initiating capacity in breast cancer cell lines.Methods:Epithelial-mesenchymal transition was induced in five breast cancer cell lines and one normal breast cell line by EMT-related cytokine stimulation. Mesenchymal-epithelial transition (MET) was induced by stably overexpressing miR-200c in three mesenchymal-like breast cancer cell lines. Molecular expression and cell function analysis were performed to evaluate the effect of EMT or MET on tumour-initiating capacity and other biological characteristics.Results:The induction of EMT did not enhance tumour-initiating capacity but, instead, conferred a CD44
+ /CD24−/low phenotype as well as cell proliferation, migration, and resistance to doxorubicin and radiation on breast cancer cell lines. Furthermore, MET did not lead to inhibition or loss of the tumour-initiating capacity in mesenchymal-like breast cancer cell lines, but it markedly attenuated other malignant properties, including proliferation, invasion, and resistance to therapy.Conclusions:Epithelial-mesenchymal transition does not alter tumour-initiating capacity of breast cancer cells but some other biological characteristics. Therefore, EMT and tumour-initiating capacity may not be directly linked in breast cancer cell lines. [ABSTRACT FROM AUTHOR]- Published
- 2014
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24. Adaptation of intertidal biofilm communities is driven by metal ion and oxidative stresses.
- Author
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Weipeng Zhang, Yong Wang, On On Lee, Renmao Tian, Huiluo Cao, Zhaoming Gao, Yongxin Li, Li Yu, Ying Xu, and Pei-Yuan Q
- Subjects
METAL ions ,OXIDATIVE stress ,MARINE organisms ,BIOFILMS ,STRAINS & stresses (Mechanics) - Abstract
Marine organisms in intertidal zones are subjected to periodical fluctuations and wave activities. To understand how microbes in intertidal biofilms adapt to the stresses, the microbial metagenomes of biofilms from intertidal and subtidal zones were compared. The genes responsible for resistance to metal ion and oxidative stresses were enriched in both 6-day and 12-day intertidal biofilms, including genes associated with secondary metabolism, inorganic ion transport and metabolism, signal transduction and extracellular polymeric substance metabolism. In addition, these genes were more enriched in 12-day than 6-day intertidal biofilms. We hypothesize that a complex signaling network is used for stress tolerance and propose a model illustrating the relationships between these functions and environmental metal ion concentrations and oxidative stresses. These findings show that bacteria use diverse mechanisms to adapt to intertidal zones and indicate that the community structures of intertidal biofilms are modulated by metal ion and oxidative stresses. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
25. The tumor suppressor Caliban regulates DNA damage-induced apoptosis through p53-dependent and -independent activity.
- Author
-
Wang, Y, Wang, Z, Joshi, B H, Puri, R K, Stultz, B, Yuan, Q, Bai, Y, Zhou, P, Yuan, Z, Hursh, D A, and Bi, X
- Subjects
COLON cancer treatment ,GENETICS of colon cancer ,DNA damage ,GENETIC regulation ,APOPTOSIS ,P53 antioncogene ,GENETIC recombination - Abstract
We previously identified Caliban (Clbn) as the Drosophila homolog of human Serologically defined colon cancer antigen 1 gene and demonstrated that it could function as a tumor suppressor in human non-small-cell lung cancer (NSCLC) cells, although its mode of action was unknown. Herein, we identify roles for Clbn in DNA damage response. We generate clbn knockout flies using homologous recombination and demonstrate that they have a heightened sensitivity to irradiation. We show that normal Clbn function facilitates both p53-dependent and -independent DNA damage-induced apoptosis. Clbn coordinates different apoptosis pathways, showing a two-stage upregulation following DNA damage. Clbn has proapoptotic functions, working with both caspase and the proapoptotic gene Hid. Finally, ecotopic expression of clbn
+ in NSCLC cells suppresses tumor formation in athymic nude mice. We conclude that Caliban is a regulator of DNA damage-induced apoptosis, functioning as a tumor suppressor in both p53-dependent and -independent pathways. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
26. RY10-4, a novel anti-tumor compound, exhibited its anti-angiogenesis activity by down-regulation of the HIF-1[alpha] and inhibition phosphorylation of AKT and mTOR.
- Author
-
Liu Z, Yuan Q, Zhang X, Xiong C, Xue P, and Ruan J
- Published
- 2012
- Full Text
- View/download PDF
27. Be alert to tuberculosis-mediated glomerulonephritis: a retrospective study.
- Author
-
Sun, L., Yuan, Q., Feng, J., Yao, L., Fan, Q., Ma, J., and Wang, L.
- Subjects
- *
GLOMERULONEPHRITIS , *MYCOBACTERIUM tuberculosis , *TUBERCULOSIS diagnosis , *MYCOBACTERIAL diseases , *HEMATURIA , *DNA polymerases - Abstract
Mycobacterium tuberculosis infection causing glomerulonephritis is a rare disorder. This retrospective study analyzed the clinical characteristics of patients diagnosed with tuberculosis-mediated glomerulonephritis (TB-GN) between 2002 and 2009, as well as the diagnostic tools used. These findings were then compared with those of patients with primary glomerulonephritis (P-GN). The records of all patients were reviewed. The diagnosis of TB-GN was based on renal hematuria and/or proteinuria and cure after antituberculosis therapy alone plus urine culture positive for M. tuberculosis, demonstration of typical tubercle granulomas on renal biopsy specimens, or the detection of M. tuberculosis DNA by polymerase chain reaction (PCR) on renal specimens. Forty-six patients with TB-GN and 49 patients with P-GN were included. Compared with patients in the P-GN group, most (76%) patients with TB-GN had a history of TB. Systemic symptoms were much more frequent in patients with TB-GN than local genitourinary symptoms. Serological testing showed a statistical difference between the two groups. Immunoglobulin A nephropathy was found in the majority (72%) of patients with TB-GN. M. tuberculosis DNA detection was positive in 39 (84.8%) patients, a much higher positive rate of diagnosis than that with urine culture for M. tuberculosis. The manifestation of TB-GN is atypical and nonspecific. It warrants a high index of suspicion when patients with renal hematuria and proteinuria fail to respond to standard treatments for P-GN. Clinicians should pay close attention to the medical history and results of special laboratory tests. M. tuberculosis DNA detection on renal biopsy specimens should be considered in order to confirm the diagnosis of TB-GN. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
28. A meta-analysis and systematic review of prophylactic endoscopic treatments for postpolypectomy bleeding.
- Author
-
Li, L. Y., Liu, Q. S., Cao, Y. J., Yuan, Q., Liang, S. W., and Qu, C. M.
- Subjects
HEMORRHAGE ,COLONOSCOPY ,SURGICAL complications ,ELECTROCOAGULATION (Medicine) ,META-analysis ,SYSTEMATIC reviews - Abstract
Purpose: The aim of this meta-analysis and systematic review was to determine whether bleeding prophylaxis benefits patients after colonoscopic polypectomy. Methods: A systematic review of the literature was performed to find prospective randomized controlled trials of postpolypectomy hemorrhage prophylaxis. Studies were selected according to specific criteria and analyzed to generate pooled data. Results: Eight studies encompassing 2,595 polyps met the criteria for the meta-analysis. The rate of early bleeding was significantly decreased relative to the control when a single prophylactic technique was used [2.58% vs. 8.15%, OR = 0.34 (95% CI, 0.20-0.58), P < 0.0001]. The use of multiple prophylactic techniques resulted in a lower early postpolypectomy hemorrhage rate compared with the use of a single prophylactic technique [0% vs. 8.41%, OR = 0.12 (95% CI, 0.03-0.47), P = 0.002]. The late bleeding rate did not differ significantly between the monotherapy and control groups [0.61% vs. 1.39%, OR = 0.37 (95% CI, 0.11-1.28), P = 0.12], and the use of combined preventative techniques did not significantly decrease the late postpolypectomy bleeding (PPB) rate compared with use of a single prophylactic method [1.43% vs. 2.05%, OR = 0.70 (95% CI, 0.32-1.55), P = 0.38]. Conclusion: Prophylactic endoscopic treatments are effective at reducing early PPB after colonoscopic polypectomy. However, patients with late PPB may not benefit from bleeding prophylaxis. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
29. Physiological and proteomic analyses of Alternanthera philoxeroides under zinc stress.
- Author
-
Yuan, Q. H., Shi, G. X., Zhao, J., Zhang, H., and Xu, Q. S.
- Subjects
- *
ALTERNANTHERA phylloxeroides , *ZINC , *AMARANTHACEAE , *PROTEOMICS , *HEMOPROTEINS - Abstract
In this study, physiological, biochemical, and proteomic changes of Alternanthera philoxeroides leaves under zinc stress were investigated. Zinc is an essential micronutrient for plants, but it can be toxic at higher concentrations. Accumulations of zinc and MDA in leaves increased significantly with the increase of zinc concentrations. Zn considerably changed the activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). Zn also altered the antioxidant level, such as reduced glutathione (GSH) and ascorbic acid (AsA). Therefore, it seems that zinc induced oxidative stress in the leaves of A. philoxeroides, in which we found enhancement of antioxidant enzyme activities and antioxidant concentrations. Protein profiles analyzed by two-dimensional electrophoresis revealed that five protein spots were up-regulated in zinc-treated samples. These differentially displayed proteins were identified by mass spectrometry. The up-regulation of some antioxidant enzymes and stress-related proteins clearly indicated that excess zinc generates oxidative stress that might be disruptive to other important metabolic processes. These results indicate a good correlation between the physiological and biochemical changes in A. philoxeroides leaves exposed to excess zinc. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
30. Nucleotide sequence variation within the human tyrosine kinase B neurotrophin receptor gene: association with antisocial alcohol dependence.
- Author
-
Xu, K., Anderson, T. R., Neyer, K. M., Lamparella, N., Jenkins, G., Zhou, Z., Yuan, Q., Virkkunen, M., and Lipsky, R. H.
- Subjects
GENES ,HEREDITY ,MOLECULAR genetics ,NEURONS ,ALCOHOL - Abstract
To identify sequence variants in genes that may have roles in neuronal responses to alcohol, we resequenced the 5′ region of tyrosine kinase B neurotrophin receptor gene (NTRK2) and determined linkage disequilibrium (LD) values, haplotype structure, and performed association analyses using 43 single nucleotide polymorphisms (SNPs) covering the entire NTRK2 region in a Finnish Caucasian sample of 229 alcohol-dependent subjects with antisocial personality disorder (ASPD) and 287 healthy controls. Individually, three SNPs were associated with alcohol dependence and alcohol abuse (AD) (P-value from 0.0019 to 0.0059, significance level was set at P0.01 corrected for multiple testing), whereas a common 18 locus haplotype within the largest LD block of NTRK2, a 119-kb region containing the 5′ flanking region and exons 1–15, was marginally overrepresented in control subjects compared to AD individuals (global P=0.057). Taken together, these results support a role for the NTRK2 gene in addiction in a Caucasian population with AD and a subtype of ASPD.The Pharmacogenomics Journal (2007) 7, 368–379; doi:10.1038/sj.tpj.6500430; published online 2 January 2007 [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
31. Coronavirus envelope protein: A small membrane protein with multiple functions.
- Author
-
Liu, D. X., Yuan, Q., and Liao, Y.
- Subjects
- *
CORONAVIRUSES , *BIOLOGICAL membranes , *APOPTOSIS , *VIRUSES , *CELL communication - Abstract
Coronavirus envelope protein is a small membrane protein and minor component of the virus particles. It plays important roles in virion assembly and morphogenesis, alteration of the membrane permeability of host cells and virus-host cell interaction. Here we review recent progress in characterization of the biochemical properties, membrane topology and functions of the protein. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
32. Effects of Pb2+ on the active oxygen-scavenging enzyme activities and ultrastructure in Potamogeton crispus leaves.
- Author
-
Hu, J. Z., Shi, G. X., Xu, Q. S., Wang, X., Yuan, Q. H., and Du, K. H.
- Subjects
ANTIOXIDANTS ,CHLOROPLASTS ,ENZYMES ,NUCLEAR membranes ,CELL membranes ,PHOTOSYNTHETIC pigments - Abstract
The effects of various concentrations of Pb
2+ on the antioxidant enzyme activities and the ultrastructure in Potamogeton crispus leaves were studied. Peroxidase (POD) activity and malondialdehyde (MDA) content peaks were observed with an increase in Pb2+ concentration, whereas superoxide dismutase (SOD) and catalase (CAT) activities decreased firstly and then rose. Meantime, the chlorophyll content declined with increasing Pb2+ concentration. Simultaneously, high concentrations of Pb2+ aggravated ultrastructural damage to the leaf cells including swelling of chloroplasts, disruption and disappearance of chloroplast envelopes; swelling of mitochondrial cristae, deformation and vacuolation of mitochondria; condensation of chromatin, dispersion of nucleoli, and disruption of nuclear membrane. Changes in antioxidant enzyme activities and damage to fine structure are the results of lead-induced ROS accumulation. The estimated lethal concentration to P. crispus ranged from 10 to 15 mg/l lead. [ABSTRACT FROM AUTHOR]- Published
- 2007
- Full Text
- View/download PDF
33. Association of galanin haplotypes with alcoholism and anxiety in two ethnically distinct populations.
- Author
-
Belfer, I., Hipp, H., McKnight, C., Evans, C., Buzas, B., Bollettino, A., Albaugh, B., Virkkunen, M., Yuan, Q., Max, M. B., Goldman, D., and Enoch, M. A.
- Subjects
NEUROPEPTIDES ,GALANIN ,ALCOHOLISM ,ANXIETY ,GENETIC polymorphisms ,PEOPLE with alcoholism ,CENTRAL nervous system - Abstract
The neuropeptide galanin (GAL) is widely expressed in the central nervous system. Animal studies have implicated GAL in alcohol abuse and anxiety: chronic ethanol intake increases hypothalamic GAL mRNA; high levels of stress increase GAL release in the central amygdala. The coding sequence of the galanin gene, GAL, is highly conserved and a functional polymorphism has not yet been found. The aim of our study was, for the first time, to identify GAL haplotypes and investigate associations with alcoholism and anxiety. Seven single-nucleotide polymorphisms (SNPs) spanning GAL were genotyped in 65 controls from five populations: US and Finnish Caucasians, African Americans, Plains and Southwestern Indians. A single haplotype block with little evidence of historical recombination was observed for each population. Four tag SNPs were then genotyped in DSM-III-R lifetime alcoholics and nonalcoholics from two population isolates: 514 Finnish Caucasian men and 331 Plains Indian men and women. Tridimensional Personality Questionnaire harm avoidance (HA) scores, a dimensional measure of anxiety, were obtained. There was a haplotype association with alcoholism in both the Finnish (P=0.001) and Plains Indian (P=0.004) men. The SNPs were also significantly associated. Alcoholics were divided into high and low HA groups ( and
- Published
- 2006
- Full Text
- View/download PDF
34. Orientation of Galaxies in the Local Supercluster: A Review.
- Author
-
Hu, F. X., Wu, G. X., Song, G. X., Yuan, Q. R., and Okamura, S.
- Subjects
GALAXIES ,GALAXY clusters ,LOCAL Group (Astronomy) ,VIRGO Cluster ,SUPERCLUSTERS ,SPIRAL galaxies - Abstract
The progress of the studies on the orientation of galaxies in the Local Supercluster (LSC) is reviewed and a summary of recent results is given. Following a brief introduction of the LSC, we describe the results of early studies based on two-dimensional analysis, which were mostly not conclusive. We describe next the three-dimensional analysis, which is used widely today. Difficulties and systematic effects are explained and the importance of selection effects is described. Then, results based on the new method and modern databases are given, which are summarized as follows. When the LSC is seen as a whole, galaxy planes tend to align perpendicular to the LSC plane with lenticulars showing the most pronounced tendency. Projections onto the LSC plane of the spin vectors of Virgo cluster member galaxies, and to some extent, those of the total LSC galaxies, tend to point to the Virgo cluster center. This tendency is more pronounced for lenticulars than for spirals. It is suggested that ‘field’ galaxies, i.e., those which do not belong to groups with more than three members, may be better objects than other galaxies to probe the information at the early epoch of the LSC formation through the analysis of galaxy orientations. Field lenticulars show a pronounced anisotropic distribution of spin vectors in the sense that they lay their spin vectors parallel to the LSC plane while field spirals show an isotropic spin-vector distribution. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
35. Electron theory based explanation and experimental study on deformation behavior of Cu/Ni multilayers.
- Author
-
Ren, F., Liu, P., Zheng, M., Dong, Q., Zhou, G., and Yuan, Q.
- Abstract
Cu/Ni multilayers with various defined thickness of Cu and Ni layers were electrodeposited on low carbon steel substrates. Hardness measurements indicated that the increase in yield strength (one-third of hardness) with a decrease of layer thickness for Cu/Ni multilayers with single layer thickness at sub-micron length scale could be described by the Hall-Petch formula of the dislocation pile-up model. In the regime of few tens to a hundred nanometers of single layer thickness, the dislocation pileup-based Hall-Petch model broke down. This could be explained quantitatively according to the criterion condition on the limit size of dislocation derived from a modified Thomas-Fermi-Dirac electron theory. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
36. Analysis of Flavonoids and Phenolic Acid in Propolis by Capillary Electrophoresis.
- Author
-
Cao, Y.H., Wang, Y., and Yuan, Q.
- Abstract
A high-performance capillary electrophoresis (CE) is developed for the determination of six ingredients – rutin, ferulic acid, apigenin, luteolin, quercetin and caffeic acid – in Propolis and its extract capsules in this work. The effects of several factors such as the acidity and concentration of the running buffer, the separation voltage, the injection time and the wavelength of UV detector were investigated to find the optimum conditions. Under the optimum conditions, the analytes were separated within 14 min in a borax buffer (pH 9.2). Notably, excellent linearity was obtained over two orders of magnitude with detection limits (S/N=3) ranged from 3.7 × 10
−7 to 1.8 × 10−6 g mL−1 for all six analytes. The relative standard deviations of the migration times of six constituents ranged between 1.06% and 1.53%. The recoveries of six constituents ranged from 94.9% to 108.4%. This method was successfully used in the analysis of Propolis and its extract capsules with a relatively simple extraction procedure, and the assay results were satisfactory. [ABSTRACT FROM AUTHOR]- Published
- 2004
- Full Text
- View/download PDF
37. Imperfect nesting and Peierls instability for a two-dimensional tight-binding model.
- Author
-
Yuan, Q., Nunner, T., and Kopp, T.
- Abstract
Based on a half-filled two-dimensional tight-binding model with nearest-neighbour and next nearest-neighbour hopping the effect of imperfect Fermi surface nesting on the Peierls instability is studied at zero temperature. Two dimerization patterns corresponding to a phonon vector (π,π) are considered. It is found that the Peierls instability will be suppressed with an increase of next nearest-neighbour hopping which characterizes the nesting deviation. First and second order transitions to a homogeneous state are possible. The competition between the two dimerized states is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
38. Enhanced anthocyanin production by repeated-batch culture of strawberry cells with medium shift.
- Author
-
Zhang, W., Jin, M. F., Yu, X. J., and Yuan, Q.
- Subjects
ANTHOCYANINS ,CELL culture ,STRAWBERRIES ,PLANT cells & tissues ,PLANT growth - Abstract
Repeated-batch cultures of strawberry cells (Fragaria ananassa cv. Shikinari) subjected to four medium-shift procedures (constant LS medium, constant B5 medium, alternation between LS and B5 starting from LS and alternation between LS and B5 starting from B5) were investigated for the enhanced anthocyanin productivity. To determine the optimum period for repeated batch cultures, two medium-shift periods of 9 and 14 days were studied, which represent the end of the exponential growth phase and the stationary phase. By comparison with the corresponding batch cultures, higher anthocyanin productivity was achieved for all the repeated-batch cultures at a 9-day medium-shift period. The average anthocyanin productivity was enhanced 1.7- and 1.76-fold by repeated-batch cultures in constant LS and constant B5 medium at a 9-day shift period for 45 days, respectively. No further improvement was observed when the medium was alternated between LS (the growth medium) and B5 (the production medium). Anthocyanin production was unstable at a 14-day shift period regardless of the medium-shift procedures. The results show that it is feasible to improve anthocyanin production by a repeated-batch culture of strawberry cells. [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
39. Influence of Cr2O3 on the sintering, microstructure and mechanical performances of ZTM-Al2O3.
- Author
-
Jin, X., Gao, L., Chen, Y., and Yuan, Q.
- Published
- 2001
- Full Text
- View/download PDF
40. Two commonly expanded CAG/CTG repeat loci: involvement in affective disorders?
- Author
-
Lindblad, K., Nylander, P.-O., Zander, C., Yuan, Q.-P., Ståhle, L., Engström, C., Balciuniene, J., Pettersson, U., Breschel, T., McInnis, M., Ross, C.A., Adolfsson, R., and Schalling, M.
- Subjects
AFFECTIVE disorders ,HUMAN chromosome abnormalities - Abstract
Investigates the association between bipolar affective disorder (BAD) and CAG/CTG trinucleotide repeat expansions. Difference in ERDA1 expansion frequency between bipolar patients and matched controls or between affected and unaffected offspring in the families; Use of repeat expansion detection method in determining the association of BAD and CAG/CTG repeat loci.
- Published
- 1998
- Full Text
- View/download PDF
41. Linkage analysis of candidate loci in families with recurrent major depression.
- Author
-
Balciuniene, J., Yuan, Q.-P., Engström, C., Lindblad, K., Nylander, P.O., Sundvall, M., Schalling, M., Pettersson, U., Adolfsson, R., and Jazin, E.E.
- Subjects
- *
MENTAL depression , *HYPOMANIA - Abstract
Recurrent major depression, RMD, is characterized by the occurrence of depressive episodes in the absence of mania and/or hypomania. In linkage studies, RMD (or, in general, unipolar depression) are frequently grouped together with bipolar illnesses into a broad definition of affective disorders. However, twin studies suggest that RMD and bipolar disorders might have different genetic determinants. The objective of this study was to test a set of families with RMD for linkage to chromosomes that have been recently proposed to contain susceptibility loci for bipolar disorders: chromosomes 16, 18, 21 and the short arm of chromosome 4. We analysed five large families from the northern part of Sweden ascertained through a proband with RMD and containing several patients with RMD. For the genetic analysis, we included only severely affected individuals (those who had at least three episodes that required medical treatment) to increase the chances of finding a larger degree of genetic determination. The genetic model led to a total disease prevalence of 5% in females and 3% in males. We did not find significant evidence for linkage to any of the candidate chromosomes in the combined family set. Only one of the families showed a slight indication for linkage with markers from the pericentromeric region of chromosome 18. A genome scan analysis on an extended collaborative family material with severely affected individuals with RMD should be performed to evaluate whether RMD and bipolar disorders have a different genetic etiology. [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
- View/download PDF
42. A convenient tubulin-based quantitative assay for paclitaxel (Taxol) derivatives more effective in inducing assembly than the parent compound.
- Author
-
Lin, Chii M., Jiang, Yuan Q., Chaudhary, Ashok G., Rimoldi, John M., Kingston, David G. I., Hamel, E., Lin, C M, Jiang, Y Q, Chaudhary, A G, Rimoldi, J M, and Kingston, D G
- Abstract
A room temperature biochemical assay, based on centrifugal removal of tubulin polymer, was developed to permit ready detection of paclitaxel analogs more active than the parent compound and to permit reliable quantification of differences in activity relative to paclitaxel in terms of drug concentration. The assay was validated by comparing paclitaxel to two compounds (docetaxel and 2-debenzoyl-2-meta-azidobenzoylpaclitaxel) known to be more active under multiple reaction conditions. The assay was designed to yield a relatively high EC50 (23 microM) for paclitaxel. This was possible because paclitaxel only weakly induced tubulin assembly at room temperature in 0.4 M glutamate without exogenous GTP. Under these same reaction conditions 50% assembly occurred with 4.7 microM 2-debenzoyl-2-meta-azidobenzoylpaclitaxel and 11 microM docetaxel. These biochemical EC50 values were in agreement with the relative cytotoxicity of the three compounds for human Burkitt lymphoma CA46 cells (IC50 values for paclitaxel, docetaxel, and 2-debenzoyl-2-meta-azidobenzoylpaclitaxel were 40, 10, and 3 nM, respectively). [ABSTRACT FROM AUTHOR]
- Published
- 1996
- Full Text
- View/download PDF
43. Factors affecting membrane fouling in filtration of Saccharomyces cerevisiae in an internal ceramic filter bioreactor.
- Author
-
Zhang, W., Park, B. G., Chang, Y. K., Chang, H. N., Yu, X. J., and Yuan, Q.
- Abstract
Filtration of ethanol fermentation medium and broth by using symmetric and asymmetric ceramic membranes has been studied in an internal filter bioreactor. Factors studied included membrane structure and pore size, medium sterilization, and concentrations of glucose, yeast extract in the medium, yeast cell and protein in broth. The aim was to determine the main factors responsible for the decline in filtration performance during ethanol fermentation by Saccharomyces cerevisiae. Flux index (Fi) of a new concept has been developed to evaluate the degree of flux decline during the membrane fouling process. Fi was defined as the ratio of the membrane flux at certain filtration time ( t = t) to the initial ( t = −0) flux of pure water, not the initial ( t = +0) flux of the test fluid. Flux with sterilized medium was approximately two-fold higher than that with unsterilized medium although the reason could not be explained clearly. Glucose, interaction between glucose and yeast extract, yeast cells, and proteins in fermentation broth were found to play an important part in membrane fouling. Fi of the symmetric membrane decreased to a less extent than that of the asymmetric membrane with increasing glucose concentration. But, the result with various yeast cell concentrations turned out to be contrary. Fouling was more serious for asymmetric membrane during the filtration of fermentation supernatant. This was thought to be due to different fouling mechanisms for the two types of membrane. [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
- View/download PDF
44. Crash and energy absorption behaviour of interleaved carbon-fibre-reinforced epoxy tubes.
- Author
-
YUAN, Q., KERTH, S., KARGER-KOCSIS, J., and FRIEDRICH, K.
- Published
- 1997
- Full Text
- View/download PDF
45. Large CAG/CTG repeats are associated with childhood-onset schizophrenia.
- Author
-
Burgess, C.E., Lindblad, K., Sidransky, E., Yuan, Q.-P., Long, R.T., Breschel, T., Ross, C.A., McInnis, M., Lee, P., Ginns, E.I., Lenane, M., Kumra, S., Jacobsen, L., Rapoport, J.L., and Schalling, M.
- Subjects
NUCLEOTIDE sequence ,SCHIZOPHRENIA ,NEUROPSYCHIATRY - Abstract
Recent studies have shown an association between trinucleotide repeat expansions (TREs) and adult-onset schizophrenia (AOS). Childhood-onset schizophrenia (COS) is a severe variant of schizophrenia with onset of symptoms before age 12 years. We have used the repeat expansion detection (RED) method to investigate the occurrence of repeat expansions in a group of well-characterized COS patients as well as a set of clinically related childhood-onset psychosis cases labeled 'multidimensionally impaired' (MDI). The difference observed in the CAG/CTG RED product distribution between normal (n=44) and COS (n=36) samples was only marginally significant (P=0.036). However, male COS samples (n=20) had a significantly different RED product distribution compared to male controls (n=25, P=0.002) with longer RED products in COS. No such difference was seen in females (n[sub cont] = 19; n[sub cos] = 16; P=0.236). The difference remained significant between male COS (n=12) and male controls (n=24) when only Caucasian samples were used (P=0.003). Similarly, the RED product distribution in male MDI samples (n=18) was significantly different compared to male controls (P=0.018). Some of the detected TREs in all three populations (COS, MDI and control) correlated with expanded alleles found at the CTG18.1 locus on chromosome 18. In conclusion, we have found an association between TREs and COS. This association is specifically significant in the male population. Thus, the occurrence of an expanded trinucleotide repeat may contribute to the genetic risk of COS, possibly in combination with other factors. [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
- View/download PDF
46. Assignment of acoustic emission to the failure sequence and damage zone growth in glass fiber strand mat-reinforced structural nylon RIM composites.
- Author
-
Karger-Kocsis, J., Yuan, Q., and Czigány, T.
- Abstract
The failure sequence and the damage zone evolution of a reaction injection molded (RIM) ≈ 20 wt.% glass strand mat reinforced nylon block copolymer (NBC) was studied by acoustic emission (AE) and transmitted light microscopy. Simultaneous monitoring of the failure mode by AE and transmitted light microscopy lead to a highly reliable discrimination between the observed failure and the related AE signal characteristics based on their amplitude and energy. The failure sequence consisted of the following steps: a) fiber debonding due to crack tip blunting, b) network-type deformation of the GF mat in the relative 'soft' matrix with concomitant fiber debonding and voiding, c) bending of the strands with crack opening encouraged by matrix yielding, d) fracture of the bent strands and their filaments followed by pull-out processes. The evolution of the damage zone was also assessed by AE via localization and mapping of the related AE events. It was concluded that the damage zone reaches its maximum extension into the load direction (≈22 mm) at the maximum load. Further loading of the compact tension (CT) specimen decreases this size of the damage zone but strongly increses its extension perpendicular to it, i.e. along the crack growth direction. [ABSTRACT FROM AUTHOR]
- Published
- 1992
- Full Text
- View/download PDF
47. Macroporous gel-type styrene-divinylbenzene materials.
- Author
-
Guyot, A., Revillon, A., and Yuan, Q.
- Abstract
The title materials are produced from macroporous styrene (St)-divinylbenzene (DVB) resins prepared in the presence of a polymer solution as a porogen; the resulting beads are functionalized upon grafting St-Vinylbenzylchloride (VBC) copolymers through post-copolymerization with residual double bonds. The resulting material has been quaternized by trimethylamine at 35° C. The rate constant of that reaction is then about 6 times higher than that observed for a similar resin (same Cl content and same porous morphology) prepared by direct terpolymerization of St, DVB and VBC. [ABSTRACT FROM AUTHOR]
- Published
- 1989
- Full Text
- View/download PDF
48. Localization of fibronectin in human middle ear cholesteatoma.
- Author
-
Chao, W., Yuan, Q., and Huang, C.
- Abstract
Fibronectin was localized in human cholesteatoma tissues by immunohistochemical methods. The avidin-biotin-peroxidase complex staining method was used with specific fibronectin antibody. Fibronectin appeared to be localized in the matrix of the cholesteatoma studied, particularly on the surface of the cell membranes and the nuclei of the basal cells and in connective tissue. Fibronectin was not seen in the granular layer or in the keratin area. Fibronectin was found on the surface of granulation tissue, mononuclear cells, fibroblasts and endothelial cells of blood vessels. These findings were confirmed by the immunofluorescent staining method. Our previous study showed that fibronectin induced a migration of keratinocytes, macrophages and fibroblasts demonstrated by the Boyden's chamber chemotaxis assay. Macrophages and fibroblasts were shown to produce collagenase, a bone resorption factor, in cholesteatomatous tissue. The present study showed the presence of fibronectin in the matrix of cholesteatoma and granulation tissue, suggesting that fibronectin might play an important role in the clinical development and invasive behavior of cholesteatoma. [ABSTRACT FROM AUTHOR]
- Published
- 1988
- Full Text
- View/download PDF
49. Residual stresses in evaporated AI-Si films.
- Author
-
Wu, N. and Yuan, Q.
- Abstract
Residual stresses in vacuum evaporated thin Al-Si films were evaluated by measuring the deflection of a thin cantilevered substrate during removal of the film. Post-thermal treatment and thermal cyclings at temperatures between −269° C and 560° C were also introduced to determine their effects on the residual stresses of the films. [ABSTRACT FROM AUTHOR]
- Published
- 1969
- Full Text
- View/download PDF
50. Genome-wide profiling of multiple histone methylations in olfactory cells: further implications for cellular susceptibility to oxidative stress in schizophrenia.
- Author
-
Kano, S, Colantuoni, C, Han, F, Zhou, Z, Yuan, Q, Wilson, A, Takayanagi, Y, Lee, Y, Rapoport, J, Eaton, W, Cascella, N, Ji, H, Goldman, D, and Sawa, A
- Subjects
GENOMES ,SCHIZOPHRENIA ,OXIDATIVE stress - Abstract
A letter to the editor is presented in response to the article "Genome-wide profiling of histone methylations in olfactory cells: further implications for cellular susceptibility to oxidative stress in schizophrenia" in the August 28, 2012 issue, which focuses on histone modification changes.
- Published
- 2013
- Full Text
- View/download PDF
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