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17β-Estradiol (E2) is a multifunctional steroid hormone in modulating metabolism in vivo. Previous studies have reported that E2 could promote insulin secretion and protect β cells from apoptosis. In this study, the partial pancreatectomy (PPx) model was used to study the role of E2 in islet cell proliferation. The animals were divided into four groups, including sham control, PPx model, E2, and E2 plus estrogen antagonist (E2 plus ICI) groups. In the E2 group, 5-bromo-2′-deoxyuridine– and Ki67-positive cells significantly increased after PPx, and the protein expression of forkhead transcription factor M1, cyclin A2, cyclin B1, and cyclin E2 also significantly increased in the isolated islets. The messenger RNA expression of cyclin A2 and cyclin B2 increased in E2 treatment group. Additionally, the effects of E2 on the PPx mice were partially blocked by estrogen antagonist ICI182,780. The results indicated that E2 significantly promoted islet cell proliferation in PPx model mice, and it upregulated the expression of cell cycle genes. In conclusion, E2 treatment is beneficial for islet cell proliferation in adult mice after PPx. A partial pancreatectomy in mice may be an attractive model for the study of islet cell proliferation., Previous studies have reported that E2 could protect β cells from apoptosis. In this study, we used the mouse model of partial pancreatectomy to study the role of E2 in islet regeneration.

Based on the National Land Use/Cover Database of China (NLUD-C) in the end of the 1980s (the 1980s, hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban lands in China. In this study, the spatiotemporal evolutions of urban land size distribution as well as the influence of administrative-level on these cities were explored by combining urban spatial positions and administrative-levels. Results indicate that: 1) City size distribution using urban lands was more practical and reasonable than using non-agricultural population. 2) In the 1980s, cities with ascending urban land rank were centralized in Eastern China, specially the Changjiang (Yangtze) River Delta, the Zhujiang (Pearl) River Delta, and Beijing-Tianjin-Hebei region. Cities in Central, Western, and Northeast China mainly indicated descending urban land rank. 3) The transfer of national development focus resulted in cities with ascending urban land rank becoming evenly distributed nationwide; however, this trend was slightly centralized around Chengdu, Chongqing, and Wuhan in different periods. 4) During the 1980s to 2010, the proportion of cities with ascending urban land rank in provincial capitals, municipalities, and special administrative regions (high-level cities, hereafter) was consistently higher than those in prefecture- and county-level cities except for 2005–2010. The ranks of the majority of the prefecture- and county-level cities were mainly descending, supported by ascending; the proportion of cities with unchanged rank is small. This study breaks through the bottleneck of traditional research in the area of city size distribution by examining urban land replacing the non-agricultural population. The current study also provides scientific explanation for the healthy and reasonable development of urban land as well as the coordinated development of population urbanization and land urbanization.

Macroporous adsorption resin was used as the sorbent for solid phase extraction and determination of the trace Se content in high purity tellurium prior to hydride generation atomic fluorescence spectrometry analysis. Selenium was converted into an organic Se chelate using 3,3′-diaminobenzidine and was separated from the tellurium matrix by solid phase extraction. The resin was packed as a column for solid phase extraction. Under optimum conditions, trace Se can be quantitatively extracted and the tellurium matrix can be removed. The Se in the eluate was determined by hydride generation atomic fluorescence spectrometry. The limit of detection (3σ) of this method was 0.22 ng g− 1 and the relative standard deviation (RSD, n = 5) ranged from 2.0 to 2.5% for the three investigated tellurium samples. The proposed method was successfully applied for the determination of the trace Se content in high purity tellurium samples.

Depression is a major global public health concern. The variable effectiveness and undesirable side effects of antidepressant medication have prompted the search for alternative treatments. Olfaction plays an important role in emotion regulation in our daily life. Pleasant odorants would evoke positive emotions, inducing relaxation and calmness. The beneficial effects of vanillin aromatherapy on depression model rats were investigated in our previous research. Here, biochemical molecules including serum magnesium and brain derived nerve growth factor (BDNF) were further detected to investigate the possible underlying mechanisms. Results showed that the administration of vanillin aromatherapy restored the serum magnesium and brain BDNF which might mediate remission of depression. This suggests that vanillin aromatherapy could be considered as a potential alternative therapy for alleviating psychological responses among people suffering from major depressive disorder.

The paper, to explore mechanical properties of magnesium alloy and ceramic coatings by micro-arc oxidation, through measurement of tensile modulus of elasticity of magnesium alloy matrix, three-point bending method to measure the elastic modulus of the ceramic coatings. The results show that: can get magnesium alloy matrix elastic modulus E=50.6GPa, Poisson's ratio ν=0.3, can get micro-arc oxidation ceramic coatings elastic modulus E= 127.4GPa, Poisson's ratio ν=0.3. At the same time studied the relationship elastic modulus of the ceramic coatings with the thickness of the thickness between 20-60μm. The results show that: With the increaseing of the thickness, the ceramic coatings elastic modulus trend to increase.

Introduced in this article is the technique to acquire a high performance strengthened layer on carbon steel samples, namely, plasma alloying on the surface of Q235 steel and heat treatment technology. With this technique the alloying elements of Mo, Cr, and C can be obtained on the surface of Q235 steel samples. The content of the constituent elements is approximately up to high speed steels (HSS). The surface property required for the HSS after hardening and low tempering is attained. In the test, the alloying elements Mo and Cr were penetrated into the Q235 steel samples by glow discharge sputtering so that the content of the alloyed layer on the surface of the Q235 steel samples was about 20% Mo and 10% Cr. Two kinds of experiments were conducted. One was to carry out ultra-saturated carburization. The alloyed layer's composition was similar to molybdenum HSS with surface carburizing of more than 2.0%. The carbides of the alloyed layer were compact, uniform and disperse without a coarse eutectic ledeburite structure. The another was ion nitriding after the alloying elements of Mo and Cr were penetrated. The first process included hardening with low tempering and hardening with cryogenic treatment for 2 hr and low tempering. The second one was ion nitriding only. It was found that the surface hardness after cryogenic treatment is up to 1600 HV, much higher than that without cryogenic treatment. The abrasion test results indicate that, without the penetrated alloy elements Mo and Cr and without cryogenic treatment and ion nitriding, the friction coefficient is lower by one order of magnitude. The change in relative resistance is similar to the change in the friction coefficient, but without a proportional relationship.

TiN/Ti multi-permeating alloying layer has been formed on the low carbon steel by means of the double glow-discharge plasma surface alloying technique and hollow-cathode effect. The alloying layer was detected by axiovert 25 CA optical microscope with computer analyzing software (LEC), GDA-2 glow discharge spectroscopy (GDS), X-ray diffraction (XRD) and galvano-chemical method. The results showed that the thickness of TiN/Ti multi-permeating alloying layer was about 10 μm, the content of Ti on the surface was up to 63.48 wt% and the content of N was up to 12.46 wt%. The atom Ti and N concentrations changed gradually across the depth of the alloying layer and the preferred orientation of TiN/Ti alloying layer was crystal surface (200). The multi-permeating alloying layer and substrate were combined through metallurgy. The surface appearances of the multi-permeating alloying layer were uniform and of a compact cellular structure. The hardness of the surface was about 1600 ~ 3000 HV0.1. The corrosion resistance of the permeating TiN/Ti alloying layer in 0.5 mol/L H2SO4 solution was greatly increased and the corrosion rate was only 0.3082 g/m2. h.

The changing process of Guangxi farmland resource in recent 20 years was analyzed via 5 periods of land use data abstracted by remote sensing technique in this paper; farmland potential productivity was estimated and influence of LUCC process on farmland potential productivity was analyzed by combining with daily meteorological data from 1990 to 2010 and adopting environmental factor successive correction model. According to the remote sensing monitoring result, Guangxi farmland area was decreased by 20,843.81hm 2 in recent 20 years. Under average climate conditions from 1990 to 2010, farmland change has made the mean value of farmland potential productivity in Guangxi an accelerated decline trend. The mean value of farmland potential productivity for reclaimed farmland was 6,013.44Kg/hm 2 , and that for lost farmland was 11,408.11Kg/hm 2 , so the quality of reclaimed farmland cannot catch up with that of lost farmland. In all farmland changes, the dynamic type of turning forest into farmland contributes the most to the increase of gross farmland potential productivity, occupying 80.73% of total value for reclaimed farmland; the dynamic type of turning farmland into construction land decreased gross farmland potential productivity by the most, occupying 74.39% of total value for lost farmland. Index Terms—Farmland, potential productivity, Guangxi.

This paper used multi-periods of Landsat image data to detect the urban area change of eleven cities located in different administrator-tiers of Central and Southern China for the past three decades. Urban expanding intensity and impacts on eco-environment were quantitatively measured by Annual Urban Growth Rate (AGR) and reduction of ecosystem service value. Comparison was applied among different regions and administrator-tiers. The results showed that all cities experienced two expanding peaks in early 1990s and early 21st century. Cities in central China had a higher peak in early 21st century while the higher peak occurred in early 1990s for cities in southern China. National economic development strategy was the main cause leading to these differences. For impacts on eco-environment, urban expanding caused a significant reduction on ecosystem service value, and the mean value was region dependent, while changing tendency was administratortier dependent. A decreasing trend of reduction on ecosystem service value was observed in most provincial capital cities, while an increasing trend showed in those prefecture-level cities. The research is instructional and meaningful for city development and urban planning in central and southern China.

Urban expansion and land use change was studied in Jiangsu Province with RS and GIS technique, and driving forces was analyzed. Cities studied in this paper include 13 prefecture cities and 51 county cities. Remote sensing images include Landsat MSS, TM and ETM with time series from 1979 to 2000.