AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar ra...AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.展开更多
The sodium expansion curves of semi-graphitic cathode measured with the improved Rapoport-Samoilenko apparatus. The and TiB2/C composite cathode with different TiB2 contents were mathematic model of the sodium expansi...The sodium expansion curves of semi-graphitic cathode measured with the improved Rapoport-Samoilenko apparatus. The and TiB2/C composite cathode with different TiB2 contents were mathematic model of the sodium expansion was deduced on the basis of the experimental results. The sodium expansion parameter (a) and penetration rate factor (Q), were introduced into the model The model was validated with the experimental sodium expansion curves self-measured and reported. The results show that the variation tendency of the sodium expansion parameter (a) and penetration rate factor (Q) is consistent with that of the experimental curves. The model is capable of not only conveniently judging the cathode quality, but also favorably establishing a unified standard of the resistance to sodium penetration of cathode.展开更多
Background The neutrophil-to-lymphocyte (N/L) ratio has been associated with poor prognosis in patients with heart failure, but it has not been compared with N-terminal pro-brain natriuretic peptide (NT-proBNP) in...Background The neutrophil-to-lymphocyte (N/L) ratio has been associated with poor prognosis in patients with heart failure, but it has not been compared with N-terminal pro-brain natriuretic peptide (NT-proBNP) in elderly patients with chronic heart failure (CHF). We sought to make this comparison. Methods A total of 1355 elderly patients with CHF were analyzed. A multivariate logistic regression model was used to analyze the variables associated with atrial fibrillation (AF). Cox regression analysis was used to assess the multivariable rela- tionship between the N/L ratio, NT-proBNP level, and subsequent major cardiovascular events (MCE). Results In the multiple logistic regression analysis, the N/L ratio was demonstrated as a risk factor for AF in elderly patients with CHF [odds ratio (OR): 1.079, 95% confi- dence interval (CI): 1.027-1.134, P = 0.003]. The median follow-up period was 18 months. In a multivariable model using tertiles of both variables, the highest tertile of the N/L ratio was significantly associated with MCE [hazard ratio (HR): 1.407, 95% CI: 1.098-1.802, P = 0.007] compared with the lowest tertile. Similarly, the highest NT-proBNP tertile was also significantly associated with MCE (HR: 1.461, 95% CI: 1.104-1.934, P- 0.008). Conclusions In elderly patients with CHF, the N/L ratio is one of the important risk factors for AF and it is an inexpensive and readily available marker with similar independent prognostic power to NT-proBNP. The risk of MCE increases 1.407-fold when the N/L ratio is elevated to the highest tertile.展开更多
Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gon...Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichtbys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0~G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group (P〉0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P olivaceus.展开更多
Sodium erythorbate, antioxidant and curing accelerator, used in meat products, have no vitamin functionality. Ascorbic acid (AA), in contrast, is a powerful antioxidant, but very unstable. The application of encapsu...Sodium erythorbate, antioxidant and curing accelerator, used in meat products, have no vitamin functionality. Ascorbic acid (AA), in contrast, is a powerful antioxidant, but very unstable. The application of encapsulated AA in frankfurters could allow the incorporation of an antioxidant with vitamin functionality and improved stability. The aim of this study was to evaluate the application ofAA microcapsules in frankfurters and the effects of their application on the product. Different analyses were conducted. The values obtained for mass loss, moisture content, water activity, pH and instrumental color were not significantly different among the treatments. The frankfurters containing the microcapsutes exhibited the lowest hardness value (approximately 5,000 g), resulting in better scores in the sensory analysis. It was possible to apply the AA microcapsules without compromising the oxidative stability and physicochemical characteristics of the product, providing a promising method for protecting AA and producing fortified frankfurters.展开更多
Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertiliz...Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertilizer recommendation in agricultural and environmental sciences. Therefore, great attention has been paid to the measurement of elemental availability in soil test.展开更多
The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the ...The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the functional erdurance of nano finishinp wool fibers, in this paper, for the first time wool fibers were chemically modified by using NaClO aqueous and KMnO4 aqueous, and then chemically modified wool fibers and native wool fibers were treated using nano ZnO finishing agent, respectively. The launderability of wool fibers treated by nano finishing agent was investigated. The experimental results show that the chemically modified wool fibers have a good launderaility after being treated by nano ZnO finishing agent treating. The surface morphologies of wool fibers were observed by using SEM. It is got that there is a strong adbesion between nano ZnO and wool surface through XPS analysis.展开更多
Microcapsules of volatile oil containing Herba Schizonepetae(VOHS) were prepared by emulsion solvent diffusion method to improve the drug loading and reduce the amount of pharmaceutical excipients.Orthogonal assay was...Microcapsules of volatile oil containing Herba Schizonepetae(VOHS) were prepared by emulsion solvent diffusion method to improve the drug loading and reduce the amount of pharmaceutical excipients.Orthogonal assay was applied to optimize the preparation condition of microcapsulation,and the results illustrated that the ratio of ethyl cellulose(EC) to VOHS influenced the property of VOHS microcapsule significantly.GC-MS analysis indicated that some volatile components with low concentration in VOHS were lost after microencapsulation.The microcapsules prepared with optimum condition had good fluidity,and the holes on the surface of the microcapsules contributed to the release of VOHS.The particles of the microcapsule conformed to a normal distribution with the diameter of 45—220 μm.In the simulated intestinal fluid containing 0.2% sodium dodecyl sulfate,pulegone in VOHS microcapsule showed a certain degree of slow release.Compared with β-cyclodextrin method,the microencapsulation used in the present work could reduce the amount of excipients and increase the drug loading.It was beneficial to reduce the dose of Chinese medicines containing volatile oils.展开更多
Objective: The aim of our study was to investigate the correlation between the expression of sodium/iodide symporter, serum levels of β2-MG and prognosis of thyroid carcinoma patients. Methods: Ninty-five cases wit...Objective: The aim of our study was to investigate the correlation between the expression of sodium/iodide symporter, serum levels of β2-MG and prognosis of thyroid carcinoma patients. Methods: Ninty-five cases with thyroid carcinoma, using enzyme-linked immunosorbent assay with double-antibody sandwich to detect the serum β2-MG levels and immunehistochemistry to detect NIS expression of thyroid cancer tissue. Results: Thirty-seven cases showed positive expression of sodium/iodide symporter (38.9%) and 30 cases showed positive expression of β2-MG (31.57%). There were significant differences of NIS expression (X2 = 8.207, P = 0.017) and β2-MG expression (X2 = 10.121, P = 0.006) between different pathological types of thyroid carcinoma, but there was no correlation between the positive rate of the two research groups (r = -0.546, P = 0.633). The significant differences was observed in expression of sodium/iodide symporter (X2 = 9.272, P=0.002) and expression of β2-MG (X2 = 4.441, P = 0.035) between the group with neck lymph node metastasis and the group without neck lymph node metastasis and both positive rate was significantly negatively correlated (r = -1.000, P = 0.000). The significant differences was observed in expression of sodium/iodide symporter (X2 = 9.272, P = 0.002) and expression of β2-MG (X2 = 3.867, P = 0.043) between the group with distant organ metastasis and the group without distant organ metastasis (X2 = 11.985, P = 0.001) and both positive rate was significantly negatively correlated (r = -1.000, P = 0.000). Conclusion: There are significantly negatively correlated between neck lymph node metastasis, distant organ metastasis and expression of sodium/iodide symporter and expression of β2-MG. Thyroid cancer lymph node and distant organ metastasis, the tumor tissue NIS expression and serum levels of β2-MG is significantly negatively correlated. The detection of serum β2-MG provides clinical reference value for the effects on radionuclide therapy and prognosis assessment of thyroid carcinoma. Serum β2-MG levels is negatively correlated with prognosis in thyroid cancer patients.展开更多
Film-boiling heat transfer is a key phenomenon governing severe accident sequence in a sodium-cooled fast reactor. Experimental the fuel-coolant interaction process which may occur during a and theoretical work on fil...Film-boiling heat transfer is a key phenomenon governing severe accident sequence in a sodium-cooled fast reactor. Experimental the fuel-coolant interaction process which may occur during a and theoretical work on film-boiling heat transfer in sodium has hardly been carried out in the past. An experiment has been conducted in the early seventies to investigate sodium pool boiling. In this experiment, a hot tantalum sphere was immersed into subcooled liquid sodium. Film boiling was obtained for various sets of parameters: sodium subcooling from 4.1 K to 29. 1 K, initial sphere temperature ranging from 1,802.6 K to 2,633.7 K, sphere diameters of 1.27, 1.91 and 2.54 cm and sodium depths of 7.6 cm and 11.4 cm. In the present work, a simplified analysis based on the boundary layer theory is developed to describe pool film-boiling heat transfer on a hot sphere in liquid sodium. Two extreme cases are considered depending on sodium subcooling. In the case of high subcooling, most of the heat lost by the sphere is used to heat the sodium while for low subcooling, it is used to vaporize the liquid at the liquid-vapor interface. It will be shown that the scaling analysis predicts the heat fluxes within the order of magnitude when compared to the available experimental data. Besides, it allows an estimation of the contribution of these fluxes to the liquid heating and vaporization processes.展开更多
Radioimmunoassays were used to measure the concentration changes of plasma endothelin(ET) and atrial natriuretic peptide(ANP) during the onset and after termination of paroxysmal supraventricular tachycardia(SVT). 30 ...Radioimmunoassays were used to measure the concentration changes of plasma endothelin(ET) and atrial natriuretic peptide(ANP) during the onset and after termination of paroxysmal supraventricular tachycardia(SVT). 30 cases were reviewed and compansons with 42 normal subjects were made. There are very significant differences(P<0.0001) in the concentration changes of both plasma ET and ANP during the onset and 30 minutes after the termination of SVT. During the onset period of SVT. the plasma ET and ANP were markedly elevated and 30 minutes after its termination they were lowered significantly, but their concentrations were still 2-fold higher than ihose of the control group. As the biological effects of ANP and ET are antagonistic to each other. their parallel elevation and lowering of plasma concentrations during and.after the termination of SVT reveal that these 2 hormones parucipate in the pathophysiological process of SVT. This phenomenon is possibly one of the homeostatic regulatory functions in the organism.展开更多
This paper thoroughly studies the'. process of obtaining sulfur nanoparticles in aqueous medium from sodium polysulfide. Nanosize sulfur particles with orthorhombic structure were obtained at room temperature by mixi...This paper thoroughly studies the'. process of obtaining sulfur nanoparticles in aqueous medium from sodium polysulfide. Nanosize sulfur particles with orthorhombic structure were obtained at room temperature by mixing sodium polysulfide aqueous solution with various inorganic and organic acids. Sulfur nanoparticles were characterized by laser particle-size analyzer, X-ray diffraction, electron probe microscopy. Size of sulfur nanoparticles in aqueous dispersion is affected ;trongly by acid concentration, as well as nature of alcohols, used as wetting agents when measuring sulfur particles size iin aqueous medium. Availability of obtaining sulfur nanoparticles of 22-25 nm average si;,e in aqueous medium was revealed. High biological activity of sulfur nanoparticles and ethylalcohol composition on wheat grain couching was established.展开更多
This work focuses the effect of alkali-NaOH solution on the nature of synthesized zeolite from 2:1 Tunisian clays. This study was achieved using correlation between results obtained from X-ray diffraction (XRD) and...This work focuses the effect of alkali-NaOH solution on the nature of synthesized zeolite from 2:1 Tunisian clays. This study was achieved using correlation between results obtained from X-ray diffraction (XRD) and MAS-NMR analysis. Preliminary treatment was adopted to prepare the starting sample that is placed in contact with NaOH solution at variable concentration. A specific hydrothermal reactor, allowing the control ofpH 〉 9, temperature and a continuous stirring of the sample in the NaOH solution; was used to achieve these syntheses. The obtained results showed that, for concentration value ~IN, the final complex presented characteristic XRD and MAS-NMR line of zeolite P. For 3N solution concentration we obtained zeolite HS. All synthesize process are controlled by XRD and MAS-NMR investigation.展开更多
Clay minerals, especially authigene kaolinite, are abundant in the dawsonite-bearing sandstone from the Gudian and Qian'an regions in the southern Songliao Basin. The relationship between dawsonite and kaolinite has ...Clay minerals, especially authigene kaolinite, are abundant in the dawsonite-bearing sandstone from the Gudian and Qian'an regions in the southern Songliao Basin. The relationship between dawsonite and kaolinite has been investigated based on drilling data from 50 wells in the Jilin Oil Field and petrological cbaracteristics analyses on 23 core samples from the Gudian and Qian'an regions. The study revealed a negative relationship between the content of dawsonite and kaolinite, suggesting that kaolinite was replaced by the dawsonite. Combined with thermodynamics and geochemical analysis published previously, it is concluded that kaolinite is unstable under CO2-rich environments and can transform into dawsonite.展开更多
A water leakage on the surface of heat transfer tube in a steam generator of sodium-cooled fast reactor causes SWR (sodium-water reaction). The SWR damages the leak surface and gives rise to the leak enlargement. Mo...A water leakage on the surface of heat transfer tube in a steam generator of sodium-cooled fast reactor causes SWR (sodium-water reaction). The SWR damages the leak surface and gives rise to the leak enlargement. Most of initial leakage starts from micro leak (less than 0.5 g/s). However, the leak rate increases more than two orders of magnitude and the resultant leak damages surrounding heat transfer tubes and it brings secondary failure of the heat transfer tube. Evaluation of the leak enlargement is necessary to assess the leak rate increase, so that evaluate the possibility of secondary failure. In this study, a simulant experiment, which uses neutralization reaction, is proposed to reproduce the leak enlargement. To examine the feasibility of the experiment, numerical simulations are carried out. From the result, a funnel-shaped nozzle enlargement is observed and the shape similar to the shape of the enlarged nozzle from the SWAT (sodium-water reaction test loop) experiment.展开更多
Our previous studies have shown that zein has good biocompatibility and good mechanical properties. The first product from a porous scaffold of zein, a resorbable bone substitute, has passed the biological evaluation ...Our previous studies have shown that zein has good biocompatibility and good mechanical properties. The first product from a porous scaffold of zein, a resorbable bone substitute, has passed the biological evaluation of medical devices (ISO 10993) by the China Food and Drug Administration. However, Class III medical devices need quality monitoring before being placed on the market, and such monitoring includes quality control of raw materials, choice of sterilization method, and evaluation of biocompatibility. In this paper, we investigated four sources of zein through amino acid analysis (AAA) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in order to monitor the composition and purity, and control the quality of raw materials. We studied the effect of three kinds of sterilization method on a porous zein scaffold by SDS-PAGE. We also compared the changes in SDS-PAGE patterns when irradiated with different doses of gamma radiation. We found that polymerization or breakage did not occur on peptide chains of zein during gamma-ray (y-ray) sterilization in the range of 20-30 kGy, which suggested that γ-ray sterilization is suitable for porous zein scaffolds, Regarding cell compatibility, we found a difference between using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and a cell-counting kit-8 (CCK-8) assay to assess cell proliferation on zein film, and concluded that the CCK-8 assay is more suitable, due to its low background optical density.展开更多
The nature of the Ga-Ga bonding in Na2[Arx*GaGaArx*] (Arx* = C6H3-2,6-(C6Hs)2) has been investigated and compared with that of in Hz[Arx*GaGaArx*] using electron localization function (ELF) and orbital anal...The nature of the Ga-Ga bonding in Na2[Arx*GaGaArx*] (Arx* = C6H3-2,6-(C6Hs)2) has been investigated and compared with that of in Hz[Arx*GaGaArx*] using electron localization function (ELF) and orbital analysis. The calculation results show that in Na2[Arx*GaGaArx*], the Ga-Ga interaction is a non-classical triple bond, the heart of Na2[Arx*GaGaArx*] is the Ga2Na2 cluster rather than a simple Ga-Ga bond, and the contribution of the sodium atoms to the short Ga-Ga bond length is considerable. As the two sodium atoms are substituted by two hydrogen atoms, the Ga-Ga bond is replaced by two 3-center, 2-electron (3c-2e) Ga-H-Ga covalent bridged bonding.展开更多
Despite an effective p-type dopant for PbTe, the low solubility of Na limits the fully optimization of thermoelectric properties of Na-doped PbTe. In this work, Na-doped PbTe was synthesized under high pressure. The f...Despite an effective p-type dopant for PbTe, the low solubility of Na limits the fully optimization of thermoelectric properties of Na-doped PbTe. In this work, Na-doped PbTe was synthesized under high pressure. The formation of the desired rocksalt phase with substantially increased Na content leads to a high carrier concentration of 3.2×10^20 cm^-3 for Na0.03Pb0.97Te. Moreover, dense in-grain dislocations are identified from the microstructure analysis. Benefited from the improved power factor and greatly suppressed lattice thermal conductivity, the maximal ZT of 1.7 is achieved in the optimal Na0.03Pb0.97Te. Current work thus designates the advantage of high pressure in synthesizing PbTe-based thermoelectric materials.展开更多
基金The National Natural Science Foundation of China,No.30570480
文摘AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.
基金Project(2005CB623703) supported by the Major State Basic Research and Development Program of ChinaProject(2008AA030502) supported by the National High-Tech Research and Development Program of ChinaProject(GUIKEJI0639032) supported by the Science Fund Project of Guangxi Province, China
文摘The sodium expansion curves of semi-graphitic cathode measured with the improved Rapoport-Samoilenko apparatus. The and TiB2/C composite cathode with different TiB2 contents were mathematic model of the sodium expansion was deduced on the basis of the experimental results. The sodium expansion parameter (a) and penetration rate factor (Q), were introduced into the model The model was validated with the experimental sodium expansion curves self-measured and reported. The results show that the variation tendency of the sodium expansion parameter (a) and penetration rate factor (Q) is consistent with that of the experimental curves. The model is capable of not only conveniently judging the cathode quality, but also favorably establishing a unified standard of the resistance to sodium penetration of cathode.
文摘Background The neutrophil-to-lymphocyte (N/L) ratio has been associated with poor prognosis in patients with heart failure, but it has not been compared with N-terminal pro-brain natriuretic peptide (NT-proBNP) in elderly patients with chronic heart failure (CHF). We sought to make this comparison. Methods A total of 1355 elderly patients with CHF were analyzed. A multivariate logistic regression model was used to analyze the variables associated with atrial fibrillation (AF). Cox regression analysis was used to assess the multivariable rela- tionship between the N/L ratio, NT-proBNP level, and subsequent major cardiovascular events (MCE). Results In the multiple logistic regression analysis, the N/L ratio was demonstrated as a risk factor for AF in elderly patients with CHF [odds ratio (OR): 1.079, 95% confi- dence interval (CI): 1.027-1.134, P = 0.003]. The median follow-up period was 18 months. In a multivariable model using tertiles of both variables, the highest tertile of the N/L ratio was significantly associated with MCE [hazard ratio (HR): 1.407, 95% CI: 1.098-1.802, P = 0.007] compared with the lowest tertile. Similarly, the highest NT-proBNP tertile was also significantly associated with MCE (HR: 1.461, 95% CI: 1.104-1.934, P- 0.008). Conclusions In elderly patients with CHF, the N/L ratio is one of the important risk factors for AF and it is an inexpensive and readily available marker with similar independent prognostic power to NT-proBNP. The risk of MCE increases 1.407-fold when the N/L ratio is elevated to the highest tertile.
基金Supported by the National Natural Science Foundation of China(No.30571445)the National High Technology Research and Development Program of China(863 Program)(No.2006AA10A404)the Earmarked Fund for Modern Agro-Industry Technology Research System,China(No.nycytx-50)
文摘Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichtbys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0~G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group (P〉0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P olivaceus.
文摘Sodium erythorbate, antioxidant and curing accelerator, used in meat products, have no vitamin functionality. Ascorbic acid (AA), in contrast, is a powerful antioxidant, but very unstable. The application of encapsulated AA in frankfurters could allow the incorporation of an antioxidant with vitamin functionality and improved stability. The aim of this study was to evaluate the application ofAA microcapsules in frankfurters and the effects of their application on the product. Different analyses were conducted. The values obtained for mass loss, moisture content, water activity, pH and instrumental color were not significantly different among the treatments. The frankfurters containing the microcapsutes exhibited the lowest hardness value (approximately 5,000 g), resulting in better scores in the sensory analysis. It was possible to apply the AA microcapsules without compromising the oxidative stability and physicochemical characteristics of the product, providing a promising method for protecting AA and producing fortified frankfurters.
文摘Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertilizer recommendation in agricultural and environmental sciences. Therefore, great attention has been paid to the measurement of elemental availability in soil test.
文摘The launderability of wool fabrics treated by nano finoshing agent influences directly the functional endurance of he treated wool fabric. In order to investigate the effect of wool fibers surface modification on the functional erdurance of nano finishinp wool fibers, in this paper, for the first time wool fibers were chemically modified by using NaClO aqueous and KMnO4 aqueous, and then chemically modified wool fibers and native wool fibers were treated using nano ZnO finishing agent, respectively. The launderability of wool fibers treated by nano finishing agent was investigated. The experimental results show that the chemically modified wool fibers have a good launderaility after being treated by nano ZnO finishing agent treating. The surface morphologies of wool fibers were observed by using SEM. It is got that there is a strong adbesion between nano ZnO and wool surface through XPS analysis.
基金Supported by the Plan Issue of Shanghai Science&Technology Committee(No.13401901100)
文摘Microcapsules of volatile oil containing Herba Schizonepetae(VOHS) were prepared by emulsion solvent diffusion method to improve the drug loading and reduce the amount of pharmaceutical excipients.Orthogonal assay was applied to optimize the preparation condition of microcapsulation,and the results illustrated that the ratio of ethyl cellulose(EC) to VOHS influenced the property of VOHS microcapsule significantly.GC-MS analysis indicated that some volatile components with low concentration in VOHS were lost after microencapsulation.The microcapsules prepared with optimum condition had good fluidity,and the holes on the surface of the microcapsules contributed to the release of VOHS.The particles of the microcapsule conformed to a normal distribution with the diameter of 45—220 μm.In the simulated intestinal fluid containing 0.2% sodium dodecyl sulfate,pulegone in VOHS microcapsule showed a certain degree of slow release.Compared with β-cyclodextrin method,the microencapsulation used in the present work could reduce the amount of excipients and increase the drug loading.It was beneficial to reduce the dose of Chinese medicines containing volatile oils.
文摘Objective: The aim of our study was to investigate the correlation between the expression of sodium/iodide symporter, serum levels of β2-MG and prognosis of thyroid carcinoma patients. Methods: Ninty-five cases with thyroid carcinoma, using enzyme-linked immunosorbent assay with double-antibody sandwich to detect the serum β2-MG levels and immunehistochemistry to detect NIS expression of thyroid cancer tissue. Results: Thirty-seven cases showed positive expression of sodium/iodide symporter (38.9%) and 30 cases showed positive expression of β2-MG (31.57%). There were significant differences of NIS expression (X2 = 8.207, P = 0.017) and β2-MG expression (X2 = 10.121, P = 0.006) between different pathological types of thyroid carcinoma, but there was no correlation between the positive rate of the two research groups (r = -0.546, P = 0.633). The significant differences was observed in expression of sodium/iodide symporter (X2 = 9.272, P=0.002) and expression of β2-MG (X2 = 4.441, P = 0.035) between the group with neck lymph node metastasis and the group without neck lymph node metastasis and both positive rate was significantly negatively correlated (r = -1.000, P = 0.000). The significant differences was observed in expression of sodium/iodide symporter (X2 = 9.272, P = 0.002) and expression of β2-MG (X2 = 3.867, P = 0.043) between the group with distant organ metastasis and the group without distant organ metastasis (X2 = 11.985, P = 0.001) and both positive rate was significantly negatively correlated (r = -1.000, P = 0.000). Conclusion: There are significantly negatively correlated between neck lymph node metastasis, distant organ metastasis and expression of sodium/iodide symporter and expression of β2-MG. Thyroid cancer lymph node and distant organ metastasis, the tumor tissue NIS expression and serum levels of β2-MG is significantly negatively correlated. The detection of serum β2-MG provides clinical reference value for the effects on radionuclide therapy and prognosis assessment of thyroid carcinoma. Serum β2-MG levels is negatively correlated with prognosis in thyroid cancer patients.
文摘Film-boiling heat transfer is a key phenomenon governing severe accident sequence in a sodium-cooled fast reactor. Experimental the fuel-coolant interaction process which may occur during a and theoretical work on film-boiling heat transfer in sodium has hardly been carried out in the past. An experiment has been conducted in the early seventies to investigate sodium pool boiling. In this experiment, a hot tantalum sphere was immersed into subcooled liquid sodium. Film boiling was obtained for various sets of parameters: sodium subcooling from 4.1 K to 29. 1 K, initial sphere temperature ranging from 1,802.6 K to 2,633.7 K, sphere diameters of 1.27, 1.91 and 2.54 cm and sodium depths of 7.6 cm and 11.4 cm. In the present work, a simplified analysis based on the boundary layer theory is developed to describe pool film-boiling heat transfer on a hot sphere in liquid sodium. Two extreme cases are considered depending on sodium subcooling. In the case of high subcooling, most of the heat lost by the sphere is used to heat the sodium while for low subcooling, it is used to vaporize the liquid at the liquid-vapor interface. It will be shown that the scaling analysis predicts the heat fluxes within the order of magnitude when compared to the available experimental data. Besides, it allows an estimation of the contribution of these fluxes to the liquid heating and vaporization processes.
文摘Radioimmunoassays were used to measure the concentration changes of plasma endothelin(ET) and atrial natriuretic peptide(ANP) during the onset and after termination of paroxysmal supraventricular tachycardia(SVT). 30 cases were reviewed and compansons with 42 normal subjects were made. There are very significant differences(P<0.0001) in the concentration changes of both plasma ET and ANP during the onset and 30 minutes after the termination of SVT. During the onset period of SVT. the plasma ET and ANP were markedly elevated and 30 minutes after its termination they were lowered significantly, but their concentrations were still 2-fold higher than ihose of the control group. As the biological effects of ANP and ET are antagonistic to each other. their parallel elevation and lowering of plasma concentrations during and.after the termination of SVT reveal that these 2 hormones parucipate in the pathophysiological process of SVT. This phenomenon is possibly one of the homeostatic regulatory functions in the organism.
文摘This paper thoroughly studies the'. process of obtaining sulfur nanoparticles in aqueous medium from sodium polysulfide. Nanosize sulfur particles with orthorhombic structure were obtained at room temperature by mixing sodium polysulfide aqueous solution with various inorganic and organic acids. Sulfur nanoparticles were characterized by laser particle-size analyzer, X-ray diffraction, electron probe microscopy. Size of sulfur nanoparticles in aqueous dispersion is affected ;trongly by acid concentration, as well as nature of alcohols, used as wetting agents when measuring sulfur particles size iin aqueous medium. Availability of obtaining sulfur nanoparticles of 22-25 nm average si;,e in aqueous medium was revealed. High biological activity of sulfur nanoparticles and ethylalcohol composition on wheat grain couching was established.
文摘This work focuses the effect of alkali-NaOH solution on the nature of synthesized zeolite from 2:1 Tunisian clays. This study was achieved using correlation between results obtained from X-ray diffraction (XRD) and MAS-NMR analysis. Preliminary treatment was adopted to prepare the starting sample that is placed in contact with NaOH solution at variable concentration. A specific hydrothermal reactor, allowing the control ofpH 〉 9, temperature and a continuous stirring of the sample in the NaOH solution; was used to achieve these syntheses. The obtained results showed that, for concentration value ~IN, the final complex presented characteristic XRD and MAS-NMR line of zeolite P. For 3N solution concentration we obtained zeolite HS. All synthesize process are controlled by XRD and MAS-NMR investigation.
基金Supported by project of the National Science Foundation of China(Nos.41172091,40672074)
文摘Clay minerals, especially authigene kaolinite, are abundant in the dawsonite-bearing sandstone from the Gudian and Qian'an regions in the southern Songliao Basin. The relationship between dawsonite and kaolinite has been investigated based on drilling data from 50 wells in the Jilin Oil Field and petrological cbaracteristics analyses on 23 core samples from the Gudian and Qian'an regions. The study revealed a negative relationship between the content of dawsonite and kaolinite, suggesting that kaolinite was replaced by the dawsonite. Combined with thermodynamics and geochemical analysis published previously, it is concluded that kaolinite is unstable under CO2-rich environments and can transform into dawsonite.
文摘A water leakage on the surface of heat transfer tube in a steam generator of sodium-cooled fast reactor causes SWR (sodium-water reaction). The SWR damages the leak surface and gives rise to the leak enlargement. Most of initial leakage starts from micro leak (less than 0.5 g/s). However, the leak rate increases more than two orders of magnitude and the resultant leak damages surrounding heat transfer tubes and it brings secondary failure of the heat transfer tube. Evaluation of the leak enlargement is necessary to assess the leak rate increase, so that evaluate the possibility of secondary failure. In this study, a simulant experiment, which uses neutralization reaction, is proposed to reproduce the leak enlargement. To examine the feasibility of the experiment, numerical simulations are carried out. From the result, a funnel-shaped nozzle enlargement is observed and the shape similar to the shape of the enlarged nozzle from the SWAT (sodium-water reaction test loop) experiment.
文摘Our previous studies have shown that zein has good biocompatibility and good mechanical properties. The first product from a porous scaffold of zein, a resorbable bone substitute, has passed the biological evaluation of medical devices (ISO 10993) by the China Food and Drug Administration. However, Class III medical devices need quality monitoring before being placed on the market, and such monitoring includes quality control of raw materials, choice of sterilization method, and evaluation of biocompatibility. In this paper, we investigated four sources of zein through amino acid analysis (AAA) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in order to monitor the composition and purity, and control the quality of raw materials. We studied the effect of three kinds of sterilization method on a porous zein scaffold by SDS-PAGE. We also compared the changes in SDS-PAGE patterns when irradiated with different doses of gamma radiation. We found that polymerization or breakage did not occur on peptide chains of zein during gamma-ray (y-ray) sterilization in the range of 20-30 kGy, which suggested that γ-ray sterilization is suitable for porous zein scaffolds, Regarding cell compatibility, we found a difference between using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and a cell-counting kit-8 (CCK-8) assay to assess cell proliferation on zein film, and concluded that the CCK-8 assay is more suitable, due to its low background optical density.
基金supported by the National Natural Science Foundation of China (20973053, 21073051, 21102033, 21171047)the Natural Science Foundation of Hebei Province (B2010000371,B2011205058,B2010000368)the Education Department Foundation of Hebei Province (ZD2010126)
文摘The nature of the Ga-Ga bonding in Na2[Arx*GaGaArx*] (Arx* = C6H3-2,6-(C6Hs)2) has been investigated and compared with that of in Hz[Arx*GaGaArx*] using electron localization function (ELF) and orbital analysis. The calculation results show that in Na2[Arx*GaGaArx*], the Ga-Ga interaction is a non-classical triple bond, the heart of Na2[Arx*GaGaArx*] is the Ga2Na2 cluster rather than a simple Ga-Ga bond, and the contribution of the sodium atoms to the short Ga-Ga bond length is considerable. As the two sodium atoms are substituted by two hydrogen atoms, the Ga-Ga bond is replaced by two 3-center, 2-electron (3c-2e) Ga-H-Ga covalent bridged bonding.
基金supported by the National Natural Science Foundation of China (51525205, 51421091, and 51722209)the Key Basic Research Project of Hebei (14961013D)
文摘Despite an effective p-type dopant for PbTe, the low solubility of Na limits the fully optimization of thermoelectric properties of Na-doped PbTe. In this work, Na-doped PbTe was synthesized under high pressure. The formation of the desired rocksalt phase with substantially increased Na content leads to a high carrier concentration of 3.2×10^20 cm^-3 for Na0.03Pb0.97Te. Moreover, dense in-grain dislocations are identified from the microstructure analysis. Benefited from the improved power factor and greatly suppressed lattice thermal conductivity, the maximal ZT of 1.7 is achieved in the optimal Na0.03Pb0.97Te. Current work thus designates the advantage of high pressure in synthesizing PbTe-based thermoelectric materials.