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To reduce the current harmonics on the input side of a multi-pulse rectifier, this paper proposes a low harmonic current source series multi-pulse rectifier based on an auxiliary passive injection circuit at the DC side. The rectifier only needs to add an auxiliary passive injection circuit on the DC side of the series 12-pulse rectifier, which can change its AC input voltage from 12-step waves to 24-step waves. We analyzed the working mode of the rectifier, optimized the optimal turn ratio of the injection transformer from the perspective of minimizing the total harmonic distortion (THD) value of the input voltage on the AC side, and analyzed the diode open circuit fault in the auxiliary passive injection circuit. Test verification shows that, after using the passive harmonic injection circuit, the THD value of the input voltage of the AC side of the rectifier is reduced from 14.03% to 4.86%. The THD value of the input current is reduced from 5.30% to 2.16%. The input power factor has been increased from 98.86% to 99.83%, and the power quality has been improved. [ABSTRACT FROM AUTHOR]

To better understand the antibiotic resistance, virulence genes, and some related drug-resistance genes of Vibrio parahaemolyticus in farmed pacific white shrimp (Litopenaeus vannamei) in Ningde regions, Fujian province, we collected and isolated a total of 102 strains of V. parahaemolyticus from farmed pacific white shrimp in three different areas of Ningde in 2022. The Kirby–Bauer disk method was used to detect V. parahaemolyticus resistance to 22 antibiotics, and resistant genes (such as quinolones (qnrVC136, qnrVC457, qnrA), tetracyclines (tet A, tetM, tetB), sulfonamides (sulI, sulII, sulIII), aminoglycosides (strA, strB), phenicols (cat, optrA, floR, cfr), β-lactams (carB), and macrolides (erm)) were detected by using PCR. The findings in this study revealed that V. parahaemolyticus was most resistant to sulfamoxazole, rifampicin, and erythromycin, with resistance rates of 56.9%, 36.3%, and 33.3%, respectively. Flufenicol, chloramphenicol, and ofloxacin susceptibility rates were 97.1%, 94.1%, and 92.2%, respectively. In all, 46% of the bacteria tested positive for multi-drug resistance. The virulence gene test revealed that all bacteria lacked the tdh and trh genes. Furthermore, 91.84% and 52.04% of the isolates were largely mediated by cat and sulII, respectively, with less than 5% resistance to aminoglycosides and macrolides. There was a clear mismatch between the antimicrobial resistance phenotypes and genotypes, indicating the complexities of V. parahaemolyticus resistance. [ABSTRACT FROM AUTHOR]

Significant amounts of nitrogen and phosphorus in sediments will be released into the overlying water during the flood season in the water level fluctuation zone (WLFZ) of reservoirs that undergo periodic drying and flooding. This will result in water quality deterioration of the reservoir. In order to clarify the distribution characteristics and release behavior of nitrogen (N) and phosphorus (P) from sediments in the WLFZ of a reservoir, this study analyzed the sediment distribution characteristics and potential exchange flux sediment–water interface(SWI) through field investigations and sediment core incubation experiments. And the main factors affecting the release of N and P through the incubation experiments in sediments of the WLFZ in the reservoir were determined. Our findings indicated that the sediment in the WLFZ serves as the primary source of NH4+-N and acts as a sink for NO2-N in the overlying water of sediment. The concentration of NH4+-N in the interstitial water of sediments is the key factor that affects the water quality of Biliuhe Reservoir. Total nitrogen content of surface sediments in the WLFZ of Biliuhe Reservoir ranges from 1052.52 ± 49.39 to 3520.54 ± 30.31 mg/kg. High concentrations of N pollution are the primary increased risk of eutrophication in Biliuhe Reservoir during summer. The sediment N and P release flux of BLH1 located in the main stream is 1.67 ± 1.06 and 12.32 ± 2.42 mg·(m2·d)−1, respectively, which is smaller than that of BLH2 (3.27 ± 2.15 and 15.19 ± 2.36 mg·(m2·d)−1, respectively), BLH3 (4.24 ± 1.74 and 17.02 ± 2.47 mg·(m2·d)−1, respectively) and BLH4 (7.78 ± 2.03 and 20.56 ± 2.38 mg·(m2·d)−1, respectively) located in the tributary. It indicates that the water conveyance project located in BLH1 has an impact on nutrient scouring of sediments in the WLFZ at this site. The main water environment factor affecting the release of N and P in the sediment of the WLFZ is dissolved oxygen (DO). And the Pearson correlation coefficients between TN and TP with DO were −0.838 and −0.777, respectively (p < 0.05). At the same time, the diffusion of nutrients in the sediments can be effectively inhibited by maintaining a certain DO concentration in the overlying water. [ABSTRACT FROM AUTHOR]

The ash blockage of the rotary air preheater is a serious problem of the coal-fired boiler that urgently needs to be solved, which is caused by the adhesive deposition of ammonium bisulfate (ABS) and the fly ash. A comprehensive experimental study was performed to investigate the adhesive ash deposition characteristics based on an experimental platform established. The influences of the gas temperature, the gas velocity, the mass ratio of the ABS to the fly ash (R), and the ash particle size on the ash deposition characteristics were mainly analyzed and discussed under different conditions. The experimental results indicate that the liquid ABS is the root cause of the ash particles adhering to the heat transfer elements of the air preheater. The experimental results indicate that when the gas temperature is in the range of 420–493 K, the ABS ash deposition intensity and the ABS adhesion rate both increase with the increase in the gas temperature. When it is 493 K, the ABS adhesion rates of the corrugated plate and the positioning plate both reach maximum values, which are 31.7% and 27.9%, respectively. With the decrease in gas velocity, the total ash deposition intensity, the ABS ash deposition intensity, the ABS adhesion rate, and the growth rate of the ABS adhesion all increase. The content of ABS in the fly ash is also an important factor. When R rises, the ash deposition intensity and the ABS adhesion rate increase significantly. The particle size of the fly ash has little influence on the total ash deposition intensity, but has a great influence on the ABS ash deposition intensity and the ABS adhesion rate. With the increase in the particle size in the range of 30.8–100 μm, the ABS ash deposition intensity decreases by nearly 50%, and the ABS adhesion rates of plates A and B decrease by about 43.9% and 49.6%, respectively. According to the study results, some effective measures can be taken to solve the ash blocking problem of the rotary air preheater, including using the steam air heater, optimizing the operation parameters of the soot blower, and inhibiting ABS formation. [ABSTRACT FROM AUTHOR]

High-speed railways generate a large amount of regenerative braking energy during operation but this energy is not utilized efficiently. In order to realize the recycling of regenerative braking energy of high-speed railways, the hybrid energy storage type railway power conditioner (RPC) system is proposed. The working principle and the control strategy of the system are studied. The energy management strategy consisting of a hybrid energy storage system charging and discharging strategy and variational modal decomposition (VMD) power allocation strategy is proposed. Three system operation modes are proposed: the power of the hybrid energy storage system is decomposed by VMD and an interrelationship number is proposed to determine the lithium battery and supercapacitor power. The hardware-in-the-loop test experiments are conducted by the StarSim power electronics small-step real-time simulator from Modeling Tech and the validation analysis is carried out on MATLAB/Simulink with the actual measurement data of a traction substation on the Lanzhou–Xinjiang line. The results verify that the proposed strategy can effectively recycle the regenerative braking energy, realize the peak-shaving effect on the load, and reduce the energy consumption of the train. [ABSTRACT FROM AUTHOR]

Photovoltaics and batteries can be connected to a traction power supply system through a railway power conditioner (RPC) to switch between different control strategies. This can address power quality issues or provide emergency traction for locomotives that unexpectedly lose power and even break through traditional energy barriers in the railway field, achieving a low-carbon power supply for railway energy, and a mutual backup with substations. However, methods to coordinate the control strategies of PV and the battery locomotive traction have not been clearly revealed, nor has the actual stability of the system. In this study, to address the above issues, an emergency power supply scheme is proposed for the first time that utilizes a dual-mode RPC inverter combined with a coordinated control strategy for the PV and battery, achieving the traction of locomotives. In addition, a one-dimensional impedance model was established for the PV system, battery system, locomotive (CRH3), and RPC projected onto the dq coordinate system, and the critical amplitude margin (CAM) was defined to quantitatively analyze the sensitivity and laws of different parameters concerning the low-frequency stability of the system. At the same time, impedance ratios and passive criteria were used to reveal the stability mechanism, and parameter adjustment criteria and design suggestions were put forward. Finally, the feasibility of the emergency power supply scheme of the "PV–battery locomotive network" coupling system and the correctness of the low-frequency stability study were verified using the Starsim semi-physical experiment platform. [ABSTRACT FROM AUTHOR]

Immunogenicity is a major issue associated with the PK, efficacy, and safety evaluation of therapeutic protein products during pre-clinical and clinical studies. A multi-tiered approach consisting of screening, confirmatory, and titration assays has been widely adopted for anti-drug antibody testing. GQ1001, a recombinant humanized anti-human epidermal growth factor receptor 2 monoclonal antibody covalently linked to a cytotoxin of DM1, possesses a novel format of antibody–drug conjugates. In this study, we reported the development, validation, and application of an acid-dissociation bridging enzyme-linked immunosorbent assay for the detection of antibodies against GQ1001 in cynomolgus monkey serum. The sensitivity of the screening assay was 126.141 ng/mL in undiluted serum. The screening assay and confirmatory assay were neither affected by the naïve monkey serum nor by 2% and 5% (v/v) erythrocyte hemolysates. Moreover, the assay was not subject to interference by 2500 ng/mL of human IgG1 in the samples. Drug interference at low positive control (150 ng/mL) and high positive control (8000 ng/mL) of anti-GQ1001 antibodies was not observed when GQ1001 concentrations were below 3.125 μg/mL and 100 μg/mL, respectively. Furthermore, no hook effect was observed for the positive antibodies in the concentration range of 8 to 64 μg/mL. The validated assay was, thereafter, successfully applied to a single-dose toxicity study of GQ1001. Anti-drug antibody positive rates among dosing animals and testing samples were reported, and no significant impact was found on toxicokinetic outcomes. [ABSTRACT FROM AUTHOR]

Because of the short distance between stations in urban rail transit, frequent braking of urban rail trains during operation will generate a large amount of regenerative braking energy. Urban rail trains can reduce their actual traction energy consumption using regenerative braking energy. Therefore, an energy-efficient optimization method for urban rail trains is proposed. By taking the punctuality of trains as the premise, the weighted acceleration of trains is taken as the synergetic variable, the synergetic coefficient is introduced to construct the following consistency model, and its convergence is proved. By analyzing the influencing factors of the following consistency coordination time, an adaptive parameter adjustment strategy is designed to solve the latest secondary traction time and the corresponding maximum speed of the primary traction. In order to save communication resources, the event trigger function is used to construct trigger conditions, and the consistency algorithm is used to update the cooperative controller. The simulation results show that the weighted acceleration of the follower train achieves the following consistency on the premise of ensuring punctuality, and the actual traction energy consumption of the follower train is reduced by 5.73%. The proposed method provides a new strategy for the energy-efficient operation of urban rail trains. [ABSTRACT FROM AUTHOR]

The variations in the boiler operation conditions have a great effect on the combustion characteristics and the pollutant formation in furnaces. This work aims to investigate the effects of operational parameters on NOx formation and its distribution in furnaces using the numerical simulation method to obtain the optimum control strategy for reducing NOx emissions. The numerical simulation models of pulverized coal combustion in furnaces involving flow, heat transfer, combustion and NOx formation are established. Taking a 600 MW supercritical opposed firing pulverized coal boiler as the study object, a full-scale three-dimensional physical model of the boiler is constructed with Gambit software. On this basis, the pulverized coal combustion and the NOx formation under various boiler loads are numerically simulated using the software of Ansys Fluent 2021R1, and the accuracy and the reliability of the models established are verified by comparing the simulation data with the field test data. According to the combustion numerical simulation of 128 groups of operating conditions, the effects of boiler load, the air rate and the air temperature on combustion and NOx formation have been emphatically investigated. The simulation results indicate that the formation of NOx and the NOx concentration distribution are mainly affected by the oxygen concentration and the temperature in the furnace. Especially, the effects of the variation in the excess air coefficient, the over-fire air (OFA) ratio, the primary air ratio and the internal secondary air ratio on NOx concentration distribution vary greatly. When the air temperature increases the overall NOx concentration in the furnace increases, and the influence of the secondary air temperature and the OFA temperature is greater than that of the primary air temperature. Large amounts of simulation data are a necessary data source for further study on the NOx prediction model at the economizer outlet, which can improve the prediction ability and the generalization ability of the NOx prediction model. [ABSTRACT FROM AUTHOR]

At present, there are increasing applications for rosette diffusers for buoyant jets with a lower density than the ambient water, mainly in the discharge of wastewater from municipal administrations and sea water desalination. It is important to study the mixing effects of wastewater discharge for the benefit of environmental protection, but because the multiport discharge of the wastewater concentration field is greatly affected by the mixing and interacting functions of wastewater, the traditional research methods on single-port discharge are invalid. This study takes the rosette multiport jet as a research subject to develop a new technology of computational fluid dynamics (CFD) modeling and carry out convolutional neural network (CNN) simulation of the concentration field of a multiport buoyant jet. This study takes advantage of CFD technology to simulate the mixing process of a rosette multiport buoyant jet, uses CNNs to construct the machine learning model, and applies RSME, R2 to conduct evaluations of the models. This work also makes comparisons with the machine learning approach based on multi-gene genetic programming, to assess the performance of the proposed approach. The experimental results show that the models constructed based on the proposed approach meet the accuracy requirement and possess better performance compared with the traditional machine learning method, and they can provide reasonable predictions. [ABSTRACT FROM AUTHOR]

To improve the safety of electric vehicles, this paper analyzes the way of cooling lithium-ion batteries of electric vehicles and proposes an air-cooling scheme. First, a heat-generation model for the lithium-ion battery is prepared for numerical simulation and a finned air-cooling model is designed, which combines cold air with fins to lower the temperature of lithium-ion batteries. Through feasibility analysis, it is proved that the heat-generation model can reflect the actual heat generation of lithium-ion batteries. The cooling effect of the finned air-cooling model is also evaluated. The temperature can be 23.6 °C lower than the maximum compared with lithium-ion batteries without cooling. The cooling effect is desirable for diamond, triangle and rectangular lithium-ion battery packs, among which the rectangular battery pack achieves the most desirable effect. To conclude, to ensure the safe operation of lithium-ion batteries in electric vehicles, air cooling can be used to control their temperature, with the cooling effect in the rectangular lithium-ion battery pack being the most desirable. [ABSTRACT FROM AUTHOR]

The Alxa Block is located in the middle part of the Central Asian orogenic belt, which is the coupling belt of the North China, Tarim, and Kazakhstan Plates. The east–west-trending deep faults control stratigraphic distribution and magmatic activity in the region. To detect the EW-trending ore-controlling deep structures, a 440 km NS section of magnetotelluric sounding was conducted from Minle to Ejinaqi. The phase tensor and electrical principal axis were analyzed based on the measured data to build the exploration model. The electrical structure model along the section was obtained using nonlinear conjugate gradient (NLCG) 2D inversion. Combined with the geological, geophysical, and deposit distribution characteristics in the area, the comprehensive study of magnetotelluric sounding profile shows that the resistivity presents as zoned along the profile. The Engelwusu ophiolite mélange belt is stacked in clumps with high and low resistivity, indicating that the northern margin of the Engelwusu Belt subducts below the high-resistivity zone, representing the passive continental margin. The southern end of the Engelwusu ophiolite belt is primarily the prospecting potential area for copper–gold deposits, whereas the northern end of the Engelwusu ophiolite belt corresponds to copper polymetallic deposits. [ABSTRACT FROM AUTHOR]

The Indian Ocean Region (IOR) has become one of the main economic forces globally, and countries within the IOR have attempted to promote their intra-regional trade. This study investigates the spatiotemporal evolution of the community structures of the intra-regional trade and the impact of determinant factors on the formation of trade community structures of the IOR from 1996 to 2017 using the methods of social network analysis. Trade communities are groups of countries with measurably denser intra-trade ties but with extra-trade ties that are measurably sparser among different communities. The results show that the extent of trade integration and the trade community structures of the IOR changed from strengthening between 1996 and 2014 to weakening between 2015 and 2017. The largest explanatory power of the formation of the IOR trade community structures was the IOR countries' economic size, indicating that market remained the strongest driver. The second-largest explanatory power was geographical proximity, suggesting that countries within the IOR engaged in intra-regional trade still tended to select geographically proximate trading partners. The third- and the fourth-largest were common civilization and regional organizational memberships, respectively. This indicates that sharing a common civilization and constructing intra-regional institutional arrangements (especially open trade policies) helped the countries within the IOR strengthen their trade communities. [ABSTRACT FROM AUTHOR]

The new wave of modern rail transit and the proposal of the Belt and Road Initiative (BRI) have complicated the business patterns of the rolling stock manufacturing industry (RSMI) and the export of rolling stock products, especially in the case of countries participating in the BRI. Based on the analysis of trade patterns—which focuses on the evolution of trade links, community structures, and intraregional export competitiveness—this study aims to explore the changes in the RSMI within the BRI region from 2003 to 2017. Sequential clustering was applied to the creation of a three-phase timeline. The network models of the cumulative trade of the rolling stock products and trades of two typical categories of products were constructed in each phase for the evolution analysis. Social network analysis methods, such as the analysis of network indices and community detection, were also applied. The results show that from 2003 to 2017, the connectivity of the rolling stock trade in this region significantly increased. China was the largest exporter, with increasing trade influence and technological strength. Ukraine and Russia were less competitive and highly mutually dependent. Czechia and Austria's competitiveness remained prominent, but compared with China they lacked expansive vitality. South Korea was also an active and competitive country with strong technological prowess. These countries accounted for the majority of the exports, and were always at the center of their own separate communities, over which they maintained a sphere of influence. The grouping of countries far from any such spheres of influence changed frequently. [ABSTRACT FROM AUTHOR]

Product bilateral trade features can be organized and expressed in the Cartesian coordinate system by taking imports and exports as X and Y, which is similar to spatial visualization. Hence, geospatial expression and analysis methodologies can be applied in bilateral trade studies. In this paper, we propose a new digital trade feature map (DTFM) method for the visualization of bilateral trade features from a spatial perspective. The implementation process of DTFM can be summarized as feature extraction, visualization, and analysis. China–US bilateral trade data were used in several case studies. As the case studies show, the DTFM has the advantages of clear expression, easy operationalization and is highly extensible. Moreover, this method can provide a broader perspective for the understanding of trade features, i.e., in comprehensively considering the features of a specific product type and its neighbors. Furthermore, we propose an extensible DTFM application framework into which different trade features, different grid generation modes, and numerous spatial analysis models can be readily integrated. [ABSTRACT FROM AUTHOR]

In view of the low sensitivity, high operating temperature and poor selectivity of acetone measurements, in this paper much effort has been paid to improve the performance of acetone sensors from three aspects: increasing the surface area of the material, improving the surface activity and enhancing gas diffusion. A hierarchical flower-like Pt-doped (1 wt %) 3D porous SnO2 (3DPS) material was synthesized by a one-step hydrothermal method. The micropores of the material were constructed by subsequent annealing. The results of the experiments show that the 3DPS-based sensor's response is strongly dependent on temperature, exhibiting a mountain-like response curve. The maximum sensor sensitivity (Ra/Rg) was found to be as high as 505.7 at a heating temperature of 153 °C and with an exposure to 100 ppm acetone. Additionally, at 153 °C, the sensor still had a response of 2.1 when exposed to 50 ppb acetone gas. The 3DPS-based sensor also has an excellent selectivity for acetone detection. The high sensitivity can be explained by the increase in the specific surface area brought about by the hierarchical flower-like structure, the enhanced surface activity of the noble metal nanoparticles, and the rapid diffusion of free-gas and adsorbed gas molecules caused by the multiple channels of the microporous structure. [ABSTRACT FROM AUTHOR]

Detecting xylene gas is an important means of avoiding human harm from gas poisoning. A precise measurement demands that the gas sensor used must have high sensitivity, high selectivity, and low working temperature. To meet these requirements, in this study, Sn2+-doped NiO flower-like microspheres (SNM) with different amounts of Sn2+ synthesized by a one-step hydrothermal process were investigated. The responses of gas sensors based on different Sn2+-doped NiO materials for various targeting gases were fully characterized. It was found that all of the synthesized materials exhibited the best gas response at a working temperature of 180 degrees, which was much lower than the previously reported working temperature range of 300–500 degrees. When exposed to 10 ppm xylene, the 8 at% Sn2+-doped NiO sensor (mol ratio) exhibited the highest response, with a value of 30 (Rg/Ra). More significantly, the detection limit of the 8 at% Sn2+-doped NiO sensor for xylene is down in the ppb level. The Sn2+-doped NiO material also exhibits excellent selectivity for other gases with long-term stability and repeatability. The significant improvement in the response to xylene can theoretically be attributed to a decrease in the intrinsic hole carrier concentration, higher amounts of adsorbed oxygen and active sites. [ABSTRACT FROM AUTHOR]

In view of the low sensitivity, high operating temperature and poor selectivity of acetone measurements, in this paper much effort has been paid to improve the performance of acetone sensors from three aspects: increasing the surface area of the material, improving the surface activity and enhancing gas diffusion. A hierarchical flower-like Pt-doped (1 wt %) 3D porous SnO 2 (3DPS) material was synthesized by a one-step hydrothermal method. The micropores of the material were constructed by subsequent annealing. The results of the experiments show that the 3DPS-based sensor's response is strongly dependent on temperature, exhibiting a mountain-like response curve. The maximum sensor sensitivity (R a /R g ) was found to be as high as 505.7 at a heating temperature of 153 °C and with an exposure to 100 ppm acetone. Additionally, at 153 °C, the sensor still had a response of 2.1 when exposed to 50 ppb acetone gas. The 3DPS-based sensor also has an excellent selectivity for acetone detection. The high sensitivity can be explained by the increase in the specific surface area brought about by the hierarchical flower-like structure, the enhanced surface activity of the noble metal nanoparticles, and the rapid diffusion of free-gas and adsorbed gas molecules caused by the multiple channels of the microporous structure.

Detecting xylene gas is an important means of avoiding human harm from gas poisoning. A precise measurement demands that the gas sensor used must have high sensitivity, high selectivity, and low working temperature. To meet these requirements, in this study, Sn 2+ -doped NiO flower-like microspheres (SNM) with different amounts of Sn 2+ synthesized by a one-step hydrothermal process were investigated. The responses of gas sensors based on different Sn 2+ -doped NiO materials for various targeting gases were fully characterized. It was found that all of the synthesized materials exhibited the best gas response at a working temperature of 180 degrees, which was much lower than the previously reported working temperature range of 300-500 degrees. When exposed to 10 ppm xylene, the 8 at% Sn 2+ -doped NiO sensor (mol ratio) exhibited the highest response, with a value of 30 (R g /R a ). More significantly, the detection limit of the 8 at% Sn 2+ -doped NiO sensor for xylene is down in the ppb level. The Sn 2+ -doped NiO material also exhibits excellent selectivity for other gases with long-term stability and repeatability. The significant improvement in the response to xylene can theoretically be attributed to a decrease in the intrinsic hole carrier concentration, higher amounts of adsorbed oxygen and active sites.

Polysaccharide conjugates were alkali-extracted from green tea (TPC-A). Although it contained 11.80% covalently binding proteins, TPC-A could not bind to the Coomassie Brilliant Blue dyes G250 and R250. TPC-A had no expected characteristic absorption peak of protein in the UV-vis spectrum scanning in the range of 200-700 nm. The UV-vis wavelength of 280 nm was not suitable to detect the presence of the protein portion of TPC-A. The zeta potential of TPC-A merely presented the negative charge properties of polysaccharides instead of the acid-base property of its protein section across the entire pH range. Furthermore, TPC-A was more stable when the pH of solution exceeded 4.0. In addition, no precipitation or haze was generated in the TPC-A/(-)-epigallocatechin gallate (EGCG) mixtures during 12 h storage. TPC-A has emulsifying activity, which indicated that its protein moiety formed hydrophobic groups. Thus, it was proposed that some physical properties of TPC-A protein were shielded by its olysaccharide, since the protein moiety was wrapped by its polysaccharide chains., Competing Interests: The authors declare no conflict of interest.

The objective of the study was to prepare vinblastine microparticles by supercritical antisolvent process using N-methyl-2-pyrrolidone as solvent and carbon dioxide as antisolvent and evaluate its physicochemical properties. The effects of four process variables, pressure, temperature, drug concentration and drug solution flow rate, on drug particle formation during the supercritical antisolvent process, were investigated. Particles with a mean particle size of 121 ± 5.3 nm were obtained under the optimized process conditions (precipitation temperature 60 °C, precipitation pressure 25 MPa, vinblastine concentration 2.50 mg/mL and vinblastine solution flow rate 6.7 mL/min). The vinblastine was characterized by scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, mass spectrometry and dissolution test. It was concluded that physicochemical properties of crystalline vinblastine could be improved by physical modification, such as particle size reduction and generation of amorphous state using the supercritical antisolvent process. Furthermore, the supercritical antisolvent process was a powerful methodology for improving the physicochemical properties of vinblastine.

The studies were performed to investigate the physiological characteristics of non-obese diabetic (NOD) mice treated with FTY720. At the age of 12 weeks, each mouse was fed with FTY720 or physiological saline once a day for 10 weeks running, and their blood glucose, weight, anti-GAD antibody and organ indexes were determined. No mouse in group FTY720 (NOD mice treated with FTY720) showed diabetic symptoms. The average content of serum anti-GAD antibody in group FTY720 decreased 48.75% (P < 0.01). It was concluded that the spleen, kidney and liver of NOD mice treated with FTY720 shriveled significantly in the progression of diabetes (P < 0.01 or P < 0.05). The body weight of group FTY720 mice was slightly lower than that of the model control (MC) group and these two groups both had less body weight than the normal control (NC) group (P < 0.01). The result of tests of anti-GAD antibody suggested that FTY720 treatment could suppress the anti-GAD response.