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The article used sebacic acid and meta phenylenediamine as raw materials, and explored the synthesis process of nylon MXD10 through high-temperature and high-pressure melt polymerization. On this basis, the performance of the synthesized semi-aromatic nylon MXD10 was characterized. The structure of nylon MXD10 was analyzed using Fourier transform infrared spectroscopy. The thermal properties of nylon MXD10 were analyzed by differential scanning calorimetry and thermogravimetric analyzer. The results showed that the melting temperature and crystallization temperature of the synthesized nylon MXD10 were 175 °C and 117 °C, respectively. Thermal decomposition was a one-step decomposition method. Non isothermal crystallization kinetics analysis was also conducted on nylon MXD10, and the non isothermal crystallization kinetics of semi-aromatic nylon MXD10 were studied comprehensively through the Jeziorny equation and Mo Zhishen method. The results indicate that the crystal growth of semi-aromatic nylon MXD10 is two-dimensional, and the crystallization temperature decreases with the increase of cooling rate. The activation energy is -981.625 kJ/mol. [ABSTRACT FROM AUTHOR]

Objective: The Polygonatum cyrtonema was processed to investigated its effects on material and energy metabolism in CUMS depressed model mice. Methods: 80 KM/SPF mice were randomly divided into model group, positive group, processed P. cyrtonema group and compatible group, with male and female were equally divided. CUMS depressed mice model were established by unpredictable mild stress for 28 days. The levels of ICD, α-KGDHC, ATPs and Na+-K+ ATPase in brain, cerebellum, liver, kidney and spleen were detected by ELISA. Results: Processed P. cyrtonema and its compatibility had different effects on the enzyme levels of material and energy metabolism in both male and female mice. Compared to the positive group, each treatment group was affected significantly (P＜0.05). P. cyrtonema could significantly increase the α-KGDHC content in brain, cerebellum, liver, kidney and spleen of female mice (P＜0.01), and complex differences in levels of ICD α-KGDHC, ATPs and Na+-K+ ATPase in different organs of male and female mice were observed. Conclusion: Processed P. cyrtonema and its compatibility had different effects on the enzyme levels of marerial and energy metabolism in both male and female mice. P cyrtonema group had the strongest effect on depressed mice.

OBJECTIVES The Xiuwacu Mo-W deposit is a typical hydrothermal quartz vein deposit in the Yidun island arc Cu-Mo metallogenic belt, northwest Yunnan. Numerous studies have been conducted on rock and ore chronology and petrogenesis, dynamics, but its ore-forming fluid evolution has been rarely studied. OBJECTIVES To reveal the origin and evolution of ore-forming fluids of the Xiuwacu Mo-W deposit. METHODS Scanning electron microscope (SEM) cathodoluminescence method, and in situ trace element (LA-ICP-MS) and in situ Sr (fs-LA-MC-ICP-MS) isotope analyses of scheelite. RESULTS The occurrences of scheelite and the cathodoluminescence images indicated three generations of scheelite, Ⅰ, Ⅱ, and Ⅲ, with the middle stage scheelite being the most developed. The rare earth element pattern of the scheelite in the early stage was similar to that of the porphyritic granite. It showed a right-inclined pattern with light rare earth enrichment and a moderate negative Eu anomaly (δEu=0.42). The average Mo content was 3.0%, and the average 87Sr/86Sr was 0.7098, close to the specular feldspar granite (0.7075-0.7098). Compared with scheelite in the early stage, the content of light rare earth elements in the scheelite from the middle stage was low, and Eu also had a medium negative anomaly (δEu=0.37). Mo content was reduced to an average of 2445μg/g, and 87Sr/86Sr increased to 0.7113. The rare earth distribution pattern of scheelite in the later stage showed an arched pattern with relative enrichment of middle rare earth and no Eu anomaly (δEu=0.93). Mo content of scheelite decreased to 56μg/g, and average 87Sr/86Sr was 0.7083. Conclusion From early to late, the gradual decrease of light rare-earth elements, especially La and Ce, in scheelite indicates the crystallization of bastnaesite. The increase in δEu and the sharp decrease in Mo content indicate the transformation of ore-forming fluids from oxidation to reduction. The change of Sr isotope composition indicates the change in the source of ore-forming materials. The magmatic fluid contributed a lot in the early stage, and the large-scale interaction between the magma-hydrothermal fluids and surrounding rocks is responsible for the formation of scheelite in the middle stage. The strata provide amounts of Ca for scheelite formation, indicating that strong water-rock interaction played an important role in the formation of the deposit.

BACKGROUND The Nanyangtian scheelite deposit is an important skarn scheelite deposit in Yunnan Province, which is located in Laojunshan W-Sn deposit area, Southeast Yunnan. Due to its complex geological background and multi-stage metallogenic characteristics, its mineralization age and genesis remain controversial. OBJECTIVES To explore the metallogenic age, genesis and material origins of two types of scheelite deposits in order to explore formation patterns. METHODS Molybdenum Re-Os isotope dating was used to constrain the age, whereas in situ trace element and in situ Sr isotopes of scheelite were used to determine the composition of trace elements and Sr isotopes in scheelite. RESULTS The Re-Os isochron age of molybdenite associated with scheelite in the feldspar-quartz mineral vein of Nanyantian was 151.0±1.3Ma, younger than the age of skarn mineralization, indicating a later mineralization event. The skarn-type scheelite was enriched in light rare earth elements with negative Eu anomaly (δEu=0.46). The average content of ∑REE, Mo and Sr in skarn scheelite were 65.60, 240.16 and 883.43μg/g, respectively. Feldspar-quartz vein-type scheelite showed a flat rare earth pattern with positive Eu anomaly (δEu=2.8) and average content of ∑REE, Mo and Sr were 194.40, 16.01 and 129.26μg/g, respectively. respectively. The skarn scheelite had a relatively low and uniform 87Sr/86Sr value of 0.71319 to 0.71491, indicating that the ore-forming fluids were mainly magmatic-hydrothermal in origin, whereas feldspar-quartz vein type scheelite had a wide 87Sr/86Sr range of 0.71537 to 0.72803, with an average of 0.72079, characteristic of metamorphic fluids. CONCLUSIONS The differences in trace and rare earth element contents between two types of mineralization indicate that they have different fluid sources. The negative Eu anomaly of the skarn-type scheelite indicates a high oxygen fugacity environment, whereas the feldspar-quartz vein-type scheelite is formed in a reductive environment in terms of positive Eu anomaly. Sr isotopes of two different types of scheelite display a feature of binary mixing, indicating that feldspar-quartz vein-type scheelite has a superimposed transformation effect on skarn-type scheelite, and the strong metasomatism of ore-forming fluids and surrounding rocks is the key to the formation of scheelite.

BACKGROUND The Huize ultra-large lead-zinc deposit is a typical MVT or HZT type deposit in the lead-zinc polymetallic belt. This deposit is known as a unique metallogenic system and germanium enrichment. Due to the low mineralization temperature and lack of suitable dating minerals, the age of the ore deposits has been controversial. OBJECTIVES To precisely date the mineralization age by Negative Thermal Ionization Mass Spectrometry (NTIMS) Re-Os isotope analyses and discuss the Himalayan metallogenic dynamic process in the Huize ultra-large lead-zinc deposit. METHODS NTIMS Re-Os isotope analyses were carried out on pyrite, galena, and sphalerite samples collected from the Huize ultra-large lead-zinc deposit. The Re-Os isochron age from the pyrite, galena, and sphalerite samples was used to constrain mineralization age. The initial 187Os/188Os values were used to trace the material sources. RESULTS The Re-Os isochron age of the pyrite samples is 40.7±2.6 Ma (2σ, n=9) with a model weighted average age of 40.0±2.6 Ma (2σ, n=8). The sphalerite and galena samples have model ages of 38.24±0.41 Ma and 36.57±0.40 Ma, respectively. Furthermore, the initial 187Os/188Os values of the pyrite samples vary from 0 to 0.26, whereas those of the sphalerite and galena samples are 0.46 and 0.41, respectively. CONCLUSIONS The Re-Os isochron ages indicate that the mineralization for the Huize ultra-large lead-zinc deposit occurred during the Eocene period. Based on regional ore controlling structure, tectono-lithofacies alteration characteristics in Northeastern Yunnan and the isochron ages results, a two-stage (Yanshanian and Himalayan) tectonic-fluid metallogenic model for the Huize Ultra-large lead-zinc deposit is inferred.

BACKGROUND The Kunyang phosphate deposit in central Yunnan is the largest marine sedimentary phosphorite deposit in China. The deposit is hosted in black shale of the Lower Cambrian Meishucun Formation. However, there is still some controversy on the material source of the phosphorite and the deposition age of the black shale. OBJECTIVES To precisely date the black shale and provide direct constraint for the depositional age of the phosphorite and to better understand the successive depositional environment evolution from the phosphorite to black shale in vertical profiles. METHODS Negative Thermal Ionization Mass Spectrometry (NTIMS) Re-Os isotope tracer and dating studies were performed on phosphorite of Zhongyicun Member and black shale of Shiyantou Member in the Kunyang phosphate deposit. RESULTS The Re-Os isochron age of black shale in the Shiyantou Member is 521.9±5.4 Ma, which directly constrains the deposition age of black shale in the Kunyang Phosphate deposit. The phosphorite and black shale samples have initial 187Os/188Os values from 0.6576 to 0.7671 and of 0.887, respectively. The phosphorite and black shale samples have 187Re/188Os values of 2.582-240.5 and 96.24-341.8, respectively. The δEu and δCe values of trace elements in the phosphorite and black shale show changes from low to high in the vertical profile. This evidence indicates that the formation of the Kunyang phosphorus deposit occurred in the period of rapid erosion in the mainland and a large amount of terrigenous debris involvement in diagenesis-mineralization also occurred. CONCLUSIONS Based on previous studies, the atmospheric oxygen content increased rapidly, aggravating the weathering of the continental crust and the input of a large number of highly radioactive terrestrial Os caused the initial 187Os/188Os initial ratio to increase gradually during the Cambrian Period. In addition, due to the rise of the global sea level, the paleo-marine environment of the Lower Cambrian Meishucun gradually changed from shallow water oxidization to deep water reduction. The Kunyang phosphorus deposit formed during the early stages of the sea-inward-cycle sedimentation.

We examined the effects of temperature on SOC mineralization rate (Cmin) and enzyme kinetic parameters in soils of two different latitudinal forests, i.e., broad-leaved Korean pine forest in Changbai Mountain at higher latitude and evergreen broad leaved forest in Dinghu Mountain at lower latitude. The results showed that the soil Cmin increased with temperature, and the Cmin and ...) of the Changbai Mountain forest soil were higher than those of the Dinghu Mountain forest soil. The maximal rates of velocity (Vmax) and the half saturation constant (Km) of the Changbai Mountain forest soil were higher relative to the Dinghu Mountain soil for both soil β glucosidase (βG) and N-acetyl-β-D-glucosaminidase (NAG), but being opposite for catalytic efficiency (Vmax/Km). Both Vmax and Vmax/Km of βG and NAG increased with the increase of incubation temperature, while Km decreased, i.e., the affinity of enzymes to the substrate were increased. Inconsistent with the soil...), ...) and Q10(Km) of the soil βG were higher in Dinghu Mountain forest soil than those in the Changbai Mountain forest soil. The mechanisms underlying the effects of temperate variation on Cmin and the enzyme kinetic parameters were different, and thus the temperature sensitivity of Cmin and enzyme kinetic parameters should be considered differentially in the models of soil biochemical process. [ABSTRACT FROM AUTHOR]

The article discusses a study on expression and activity of New Delhi metal-ß-lactamase-1 based on culture temperature, inducing time and Isopropyl ß-D-1-thiogalactopyranoside concentration to study expression conditions of recombinant protein. It states that protein was identified by matrix-assisted laser desorption-ionization (MALDI-TOF-MS) and ethylenediaminetetraacetic acid (EDTA) has an inhibitory effect on fusion protein enzymatic activity in vitro.

A pot experiment was conducted to study the effect of spent mushroom compost ( SMC) in alleviating greenhouse soil secondary salinization and cabbage salt stress. With the amendment of SMC, the salinized soil after 60 day cabbage cultivation had a pH value close to 7. 0, its organic matter and available phosphorous contents increased significantly, and the increment of total water-soluble salt content reduced, compared with the control. When the amendment amount of SMC was 10 g ∙ kg-1 the increment of soil water soluble salt content was the least, suggesting that appropriate amendment with SMC could reduce the salt accumulation in greenhouse soil. Amendment with SMC increased the cabbage seed germination rate, plant height, plant fresh mass, chlorophyll SPAD value, and vitamin C content, and decreased the proline content significantly. All the results indicated that SMC could improve the growth environment of greenhouse cabbage, and effectively alleviate the detrimental effect of salt stress. [ABSTRACT FROM AUTHOR]

We examined the effects of temperature on SOC mineralization rate (C min ) and enzyme kinetic parameters in soils of two different latitudinal forests, i.e., broad-leaved Korean pine forest in Changbai Mountain at higher latitude and evergreen broad-leaved forest in Dinghu Mountain at lower latitude. The results showed that the soil C min increased with temperature, and the C min and Q10(C min ) of the Changbai Mountain forest soil were higher than those of the Dinghu Mountain forest soil. The maximal rates of velocity (V max ) and the half-saturation constant (K m ) of the Changbai Mountain forest soil were higher relative to the Dinghu Mountain soil for both soil β-glucosidase (βG) and N-acetyl-β-D-glucosaminidase (NAG), but being opposite for catalytic efficiency (V max /K m ). Both V max and V max /K m of βG and NAG increased with the increase of incubation temperature, while K m decreased, i.e., the affinity of enzymes to the substrate were increased. Inconsistent with the soil Q10 (C min ), Q10(V max ) and Q 10(K m ) of the soil βG were higher in Dinghu Mountain forest soil than those in the Changbai Mountain forest soil. The mechanisms underlying the effects of temperate variation on C min and the enzyme kinetic parameters were different, and thus the temperature sensitivity of C min and enzyme kinetic parameters should be considered differentially in the models of soil biochemical process.

Currently, reasonable disposal of municipal sewage sludge is one of the important issues in the field of resources and environmental science. Sludge is rich in large amounts of organic matter and available nutrients, promoting soil fertility, soil physical structure and biological properties. However, sludge contains a variety of heavy metals, organic contaminants and other hazardous substance, especially heavy metals, which are the bottlenecks of agricultural application of sludge. To improve the sewage sludge utilization efficiency and decrease the effect on soil, this essay made a summary on domestic and foreign studies on plant-soil interaction ecosystem with sewage sludge to provide a theoretical basis and scientific guidance for advancing sewage sludge utilization efficiency.

Enhanced fertilization could decrease nitrogen utilization rate and increase carbon and nitrogen leaching, leading to water pollution in agricultural ecosystem. A long-term field experiment had been established on a reddish paddy soil of Qianyanzhou Ecological Experimental Station (114 degrees 53'E, 26 degrees 48'N) in Jiangxi Province in 1998. Soil solution samples were collected by clay tube and vacuum pump. Four fertilizer species treatments were selected: control with no fertilizer (CK), straw return (ST), nitrogen, phosphorus and potassium mineral fertilizers (NPK) and pig manure (OM), aiming to evaluate the effects of different species of fertilizer on carbon and nitrogen leaching in a double rice cropping system. The results showed that: (1) ammonium nitrogen (NH4(+) -N) was the major type of N in soil leachate in reddish paddy soil. The application of NPK could significantly increase the ammonium nitrogen concentration (1.2 mg x L(-1) +/- 0.1 mg x L(-1)) compared with the CK, ST and OM treatments, and the application of OM could significantly increase the dissolved organic carbon (DOC) concentration (27.3 mg x L(-1) +/- 1.6 mg x L(-1)) in soil leachate. The carbon and nitrogen leaching were more notable in the vegetative growth stage than the reproductive growth stage of rice (P < 0.05); (2) the long-term application of NPK and OM increased the NH4(+) -N, DOC, soil organic carbon (SOC) and total nitrogen (TN) contents. The NPK was best beneficial to improve TN contents and OM to improve SOC contents. (3) The DOC contents in soil leachate and SOC in paddy soil had a positive correlation (P < 0.01), while NH4(+) -N contents in soil leachate and TN contents in paddy soil had a positive correlation (P < 0.01).

Objective: To understand the biochemical characteristics, virulence genes and pathogenicity of Shigella flexneri Xv isolated in Beijing., Methods: 61 strains of S. flexneri Xv isolated from diarrhea patients in Beijing were systematically determined through biochemical reactions and serological tests. Application of PCR technique in detection of virulence genes on ipaH, sen, virF, ial and pulsed-field gel electrophoresis (PFGE) was used to identify the related characteristics and on rat lung slices to determine its pathogenicity., Results: All of the S. flexneri Xv could ferment glucose, mannitol, melibiose and arabinose. Using serum agglutination, we found that the antigen structure was (IV: 7, 8). IpaH, sen, virF and ial that carried rates of virulence genes appeared to be 100%, 81.97%, 75.41% and 80.30%, respectively. Among 61 strains of S. flexneri Xv, the PFGE typing of Shigella bacteria could be divided into 25 belt types while the results from rat lung slices showed inflammatory change of Xv., Conclusion: S. flexneri Xv was found that it carried high rate of Shigella virulence genes, exhibiting genetic polymorphism and highly invasive.

Objective: To investigate the immunoregulation effects of umbilical cord mesenchymal stem cells (UC-MSCs) on the rats with collagen II induced arthritis (CIA)., Methods: The rats were first immunized by intradermal injection of chicken collagen type II emulsified with complete Freund's adjuvant (CFA) to monitor their swelling of foot, hair color and action state. After injected UC-MSC by caudal vein, the rats were scored with the arthritis index (AI) once a week. Then, the concentration of interleukin (IL-6), tumor necrosis factor-α (TNF-α) in serum and D-dimer (D-D), antithrombin-III (AT-III), thrombomodulin (TM) in plasma were detected by ELISA., Results: Obvious swellings of the feet were found in the experiment group compared with normal one. ELISA analysis showed that the concentrations of IL-6, TNF-α, D-D and TM in plasma of the experiment group as of (200.48 ± 15.04) ng/L, (450.25 ± 45.39) ng/L, (274.26 ± 67.93) ng/L and (9.18 ± 0.84) µg/L, respectively were higher than of(167.62 ± 0.97) ng/L, (371.44 ± 21.26) ng/L, (193.95 ± 8.22) ng/L and (6.30 ± 0.32) µg/L respectively in normal group (P < 0.05), but the concentration of AT-III \[(89.57 ± 6.40) ng/L\] was lower than normal group \[(112.82 ± 1.74) ng/L\] (P < 0.05). The levels of cytokines through the UC-MSCs treatment were significantly different from the model group (P < 0.05). After 9 weeks, these cytokines in the UC-MSCs group were mostly the same as the normal group., Conclusion: The thrombophilia status of the CIA rats was caused by immune injury. The UC-MSCs reduced the production of inflammatory cytokines and regulated and repaired the balance of coagulation and anticoagulation system of the body to cure the immune-related thrombophilia.

A pot experiment was conducted to study the effect of spent mushroom compost (SMC) in alleviating greenhouse soil secondary salinization and cabbage salt stress. With the amendment of SMC, the salinized soil after 60 day cabbage cultivation had a pH value close to 7.0, its organic matter and available phosphorous contents increased significantly, and the increment of total water-soluble salt content reduced, compared with the control. When the amendment amount of SMC was 10 g x kg(-1), the increment of soil water soluble salt content was the least, suggesting that appropriate amendment with SMC could reduce the salt accumulation in greenhouse soil. Amendment with SMC increased the cabbage seed germination rate, plant height, plant fresh mass, chlorophyll SPAD value, and vitamin C content, and decreased the proline content significantly. All the results indicated that SMC could improve the growth environment of greenhouse cabbage, and effectively alleviate the detrimental effect of salt stress.

With hydroponic culture, this paper studied the effects of different nitrogen (N) supply levels (0, 0.15, 0.3, 0.45, 0.6, 0.75 g N x L(-1)) on the seedling morphology and N allocation of Parthenocissus tricuspidata. The results showed that lower N supply retarded the development of P. tricuspidata seedling's branch; while higher N supply had significant effects in promoting the seedling's early branching and lowering the branching position on the main stem. Supplying higher amount of N increased the plant biomass and the N concentration in root, leaf and stem significantly. Compared with stem and root, leaf had the highest biomass, accounting for 50% of the total biomass, and the highest N accumulation, accounting for 60%-70% of the total accumulated N.