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To explore the effects of land use change on the potassium in soil profile under the background of rapid urbanization, we collected data of 187 soil profiles from four typical land use patterns (rice-wheat, rice-vegetable, rice-oil and garden) in Chengdu Plain. The contents of available potassium (AP), slow-acting potassium (SP), mineral potassium (MP), and total potassium (TP) in soil profile under different land use patterns and their relationships were analyzed. Our results showed that compared with the traditional rotation (rice-wheat, rice-oil), soil AP and SP contents significantly varied among different land use patterns. Rice-vegetable rotation increased the contents of AP and SP in the surface soil, while garden land increased the consumption of AP and SP in the soil. For the more stable forms, soil MP and TP, there was no significant difference in their contents under different land use patterns. In the deep soil, the content of AP in the rice-vegetable rotation pattern was significantly decreased with deepening soil layer, and the AP in traditional rotation was significantly higher than that in garden land. The trend of SP was opposite to that of AP. The difference of MP and TP in different land use patterns was small. Among the four land use patterns, the ratio of AP to TP and SP to TP in the lower layer of rice-vegetable rotation was higher than that in other patterns, while the ratio of AP to TP decreased significantly under different land use patterns at 20-40 cm. The change of SP to TP with the downward ratio of soil layer was opposite to that of AP to TP. Additionally, the ratio of MP to TP was relatively stable under different land use patterns. Therefore, different land use patterns exerted significant effects on the distribution of AP and SP in the soil profile of Chengdu Plain.为探索快速城市化背景下土地利用方式变化对土壤剖面钾素变化的影响,本研究选取成都平原4种典型土地利用方式(稻-麦、稻-蔬、稻-油和园林),基于187个土壤剖面数据,分析了不同土地利用方式下土壤剖面速效钾、缓效钾、矿物钾和全钾4种不同形态钾的含量特征及相互关系.结果表明: 从表层土壤来看,相较传统轮作(稻-麦、稻-油)而言,土地利用方式显著影响了土壤速效钾和缓效钾含量变化,稻-蔬轮作提高了表层土壤速效钾和缓效钾含量,园林用地则加剧了土壤速效钾和缓效钾的消耗.对于较为稳定的土壤矿物钾和全钾而言,其含量在不同土地利用方式间均无显著差异.从深层土壤来看,稻-蔬轮作方式下速效钾含量随土层加深下降最为明显,传统轮作土壤速效钾含量显著高于园林用地,缓效钾变化趋势与速效钾相反.不同土地利用方式土壤矿物钾和全钾含量差异较小.在4种土地利用方式中,稻-蔬轮作方式下表层土壤速效钾和缓效钾占全钾比例相对其他3种土地利用方式较高,20～40 cm土层,不同土地利用方式下速效钾占全钾比例均显著下降,缓效钾随土层向下比例变化与速效钾变化趋势恰好相反.矿物钾占全钾比例在不同土地利用方式下无显著差异.可见,不同土地利用方式对成都平原土壤速效钾和缓效钾在剖面中的分布具有显著影响.

Lj-RGD3, which contains three Arg&ndash, Gly&ndash, Asp (RGD) motifs, was first identified from the buccal glands of Lampetra japonica and has been shown to suppress the tumor progression in the previous studies. Apart from the three RGD motifs, Lj-RGD3 is also characterized by its high content of histidine in its amino acid sequence. In order to clarify whether the histidine-rich characterization of Lj-RGD3 is also associated with its anti-tumor activity, mutants were designed in which the three RGD motifs (Lj-112), or all histidines (Lj-27) or both (Lj-26) were deleted. Furthermore, a mutant (Lj-42) in which all histidines and three RGD motifs were respectively substituted with alanines and three Ala&ndash, Asp (AGD) motifs, as well as a mutant (Lj-41) in which all histidines were substituted with alanines was synthesized to avoid alterations in structure which might further cause changes in the peptides&rsquo, functions. After recombination and purification, recombinant Lj-112 (rLj-112), recombinant Lj-27 (rLj-27), recombinant Lj-41 (rLj-41), and recombinant Lj-RGD3 (rLj-RGD3) exhibited anti-proliferative activity in B16 cells, respectively, while recombinant Lj-26 (rLj-26) and recombinant Lj-42 (rLj-42) did not affect the proliferation of B16 cells significantly. In addition, the anti-proliferative activity of rLj-112 in B16 cells was due to apoptosis. Typical apoptosis features were observed, including chromatin condensation, fragmented DNA, and increased levels of cleaved caspase 3/caspase 7/nuclear enzyme poly (ADP-ribose) polymerase (PARP) in B16 cells. Similar to rLj-RGD3, rLj-112 was also capable of suppressing the migration and invasion of B16 cells by disturbing the F-actin arrangement. After labeling with FITC, rLj-112 was found localized in the cytoplasm of B16 cells, which induced the internalization of epidermal growth factor receptor (EGFR), suggesting that rLj-112 might block the EGFR mediated signaling pathway. Actually, the phosphorylation level of EGFR and its downstream signal molecules including Akt, PI3K, p38, and ERK1/2 was reduced in the rLj-112 treated B16 cells. In vivo, rLj-112 also inhibited the growth, weight, and volume of the tumors in B16 xenografted C57BL/6 mice without reducing their body weight, indicating that rLj-112 might be safe and might be used as an effective anti-tumor drug in the near future.

An environmentally benign processing approach for furfural production from xylose and xylan under very mild conditions (353–373 K) was developed with the addition of metal chlorides in ChCl–oxalic acid (a deep eutectic solvent (DES)) synthesized from cheap and renewable starting materials). ChCl–oxalic acid acted as both a Bronsted acid catalyst and a reaction medium in this catalytic route. In addition, a biphasic system with methyl isobutyl ketone as an extracting reagent (DES/MIBK) to further increase furfural yield was also proposed. This processing approach for producing furfural eliminated the large energy consumption for high pressure saturated steam and the generation of acidic effluent, which was very difficult to handle. The whole catalytic system was more environmentally friendly compared with the commercial process for furfural production.

The Chaidaer-Muli Railway (abb., Chaimu Railway) was constructed in the Qilian Mountains, where middle-latitude swampy permafrost regions are developed. About 20km embankment was equipped with heat pipes. Taking into account the characteristics of local climate, the interaction between heat pipe and ground soils and secondary standard adopted by the Chaimu railway in accordance with the national railway, the structure and design parameter of the heat pipe were optimized. The wick structure and the adiabatic section were removed; the condensing section was reduced to 1.5m in length. In order to examine the cooling effect of heat pipe in the middle-latitude swampy permafrost, a testing field was built up in the middle part of the Chaimu Railway in the year of 2008. According to the field data from 2008 to 2010, cooling radius of heat pipe is 2.4m if it is treated as a standard that mean annual ground temperature at 3.0m deep was cooled down by -0.5°C. The results proved that design interval between heat pipes can meet the demands of cooling frozen soil roadbed in the Chaimu Railway.

The Chaidaer-muli railway winds along the Datong River in the central region of the Qilian Mountains. The widely distributed permafrost along the railway is characterized by swampy and warm, which leads to the poor Engineering geologic conditions of the transportation line from the point of frozen soil. That the extending direction of the railway is nearly southeast-northwest causes its roadbed experience the yin-yang slope problems. To improve the stability of frozen soil roadbed, proactive cooling measures were adopted in a large proportion of the roadbed with permafrost, in which about 20km railway was equipped with thermosyphon. At the same time, different design parameter was adopted in the sunny and shady side slopes in the thermosyphon parts. Observation data in the experimental section with warm permafrost shows, under the condition of current thermosyphon techniques and design parameters, thermosyphon measures can effectively cool the frozen soil roadbed, substantially reduce the settlement and successfully solve the yin-yang slope problem of the railway subgrade in swampy warm permafrost.

On the base of in situ engineering tests of the crushed rock embankment, the embankment of crushed rock slope protection and the ventilated duct embankment in Qinghai–Tibet railway, the basic data of actively adjusting and cooling roadbed measures in permafrost regions have been obtained through monitoring the ground temperature in the roadbed. Analyzing the data of two freezing and thawing periods, the three measures all have certain effects of adjusting and cooling roadbed, and are advantageous to protecting permafrost under the roadbed. However, during 2–3 years after construction, the rising of artificial permafrost table still need consuming the cold energy of underground frozen soil, the thermal regime of permafrost is in instable phase.

To establish a gas chromatography method for detecting the concentration of 1,1-dichloro-1-nitroethane in air of workplaces.1,1-dichloro-1-nitroethane in air of workplaces was collected by activated charcoal tube, absorbed using carbon disulfide and analyzed by Gas Chromatography (FID) with FFAP capillary column.The linear rang of 1,1-dichloro-1-nitroethane in this method was 4.0-858.2 microg/ml, the linear regression formula was Y = 283X-1076, the correlation coefficient was 0.9999, the lowest detection concentration was 0.4 mg/m3 (3L sampling air), the relative standard deviation (RSD) was 1.8%-4.1%, the desorption efficiency was 88.5%-90.6%, the breakthrough volume was0.7 mg, the sampling efficiency was 100%, the samples could be kept at ambient temperature for at least 7 days.The indicators of this method were conformed to the requirements of "Guide for establishing occupational health standards--Determination methods of air chemicals in workplace". This method could be used to detect 1,1-dichloro-1-nitroethane in air of workplaces.

To investigate the change of the expression of the FasL receptor and apoptosis in the pathology of silicosis of the rats exposed to silica and their roles.Ninety-six wistar rats were randomizedly divided into the control group and the experimental group. The silicotic animal model was established by the direct tracheal instillation of silica into rat lungs surgically. The control rats underwent directly tracheal instillation of saline into lungs surgically. Eight rats from each group were sacrificed at different days. The expression of FasL receptor in the tissue of the model rats was detected by tissuechip microarray and immunohistochemistry and the cell apoptosis induced by silica was determined by TdT-mediated dUTP nick end-labeling method. The integral optical density of positive cells were quantitatively analyzed using Image-Pro Plus Version 4.5 for windows.The expression of FasL in the lung tissue of the model rats on the 7th, the 14th, the 21st, and the 28th day was significantly higher than that in the control group (P0.05), and peaked at the 14th day after exposure to silica. Apoptotic cells in the lung tissue of the model rats on the 1st, the 3rd, the 7th, the 14th, the 21st, and the 28th day were significantly more than those in the control group, and peaked at the 7th and the 14th day after exposure to silica.Silica can lead to apoptosis in lung tissues. FasL is expressed in all kinds of cells in the pulmonary tissues of the rats exposed to silica and leads to apoptosis. From the 7th day to 14th day, inflammatory cells dominate in apoptotic cells.