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(1) Background--As a significant ecological safeguard measure, the new round of returning farmland to forests project is of great ecological significance for ecological protection in Beijing and Tianjin. However, as a policy measure involving the withdrawal of farmers' cultivated land, whether it can guarantee the continuous in-crease of farmers' income and the stability of farmers' consumption is more worthy of discussion. (2) Methods--Based on the micro-panel data of 1115 farmers from 223 rural households in the "Beijing-Tianjin Sandstorm Source Treatment Project Monitoring" project from 2013 to 2017, this paper used the random effect model and the mediating effect model to study the impact of the new round of returning farmland to forests on the rural households' income and consumption and the effect mechanism on the rural households' consumption. (3) Results--The new round of returning farmland to forests significantly increased the total family income of the rural households, and had a significant positive impact on the total family income and operational income of the rural households at the level of 10%. However, the new round of returning farmland to forests did not improve the income structure of the rural households, and did not significantly affect the wage income, property income and transfer income of the rural households. The factors such as the farmers' education level and the number of migrant workers had a significant positive impact on the wage income. Overall, the income of the rural households was still dominated by operational income. The new round of returning farmland to forests significantly increased the total family consumption of the rural households, especially the basic consumption and productive consumption. However, there was no significant increase in children's education consumption, medical consumption and interpersonal communication consumption, which also indicated that the consumption structure of the rural households was still in basic consumption. The new round of returning farmland to forests had a positive impact on the rural households' consumption through the mediating variable of increasing the rural households' income, which verified the transmission mechanism that the farmers participated in the new round of returning farmland to forests to promote the increase of their income, and then affected their consumption. (4) Conclusions and Discussions--First, appropriately raise the subsidy standards and improve the compensation mechanism. Especially for areas prone to return to poverty and ecological functional areas, reasonable compensation standards can make up part of the losses caused by the farmers' participation in the project of returning farmland to forests. In addition, the government can implement a dynamic compensation mechanism according to the actual local situation, so that the subsidy standard is in line with the actual social and economic development situation. Second, actively promote the centralized utilization and circulation of the remaining finely fragmented land through the separation of the three rights of land. On one hand, the circulation of the fragmented land can improve the utilization rate of land, on the other hand, it can promote the flow of labor forces, so as to promote the increase of the rural households' income and the improvement of consumption structure. Third, actively implement the reform policy of forest rights, ensure clear rights to the rural households, and fully improve the promotion role of property rights income on the farmers' willingness to return farmland to forests. In addition, the farmers can also use forest rights as collateral to obtain loans to inject financial impetus into forestry production. Fourth, encourage the development of undergrowth economy and develop three-dimensional agriculture such as fruit industry, under-forest breeding industry, forage-grass planting industry, medicinal materials planting industry according to local conditions. However, while developing the corresponding undergrowth economy, we should also pay attention to the maintenance of forest nutrients, which is conducive to the sustainable and circular development of forestry. [ABSTRACT FROM AUTHOR]

本研究以文獻回顧的方法探索凱利方格法的原理與策略，再反思科學教育研究領域中可應用凱利方格法進行研究的契機與限制。凱利方格法的分析與探索主要包含下列階段：元素與構念的萃取、方格的建構與評比，以及方格的分析與解釋。這些資料分析的過程對教育研究而言具備以下優勢。首先，研究者透過凱利方格法的應用，建立有系統的資料蒐集與彙整架構，發現資料中既存的脈絡。再者，凱利方格法除了能針對單一個案所反映的方格評比進行探索與分析外，也容許跨個案的比較。在科學教育相關研究中，這些優勢適合被應用於探索學生科學學習、教師專業發展，以及評鑑科學課程與教科書等。本研究最後也說明在應用凱利方格法分析時須考量的信度與效度，以及相關的研究限制，以更明確地說明使用凱利方格法分析的策略。 This paper discusses the possible application of the repertory grid technique (RGT) in science education through a literature review. We first describe the common strategies for using RGT in psychology and education research. We then explore the reasons for using RGT and the relationship between the aforementioned strategies and the purposes of studies in the literature. Finally, we explain whether and how using RGT can assist researchers in deeply exploring science education. Three basic strategies for using RGT are summarized according to a literature review: eliciting elements and constructs, constructing the grid, and analyzing the grid. RGT enables researchers to construct and reconstruct the qualitative data on the basis of quantitative analysis, which supports exploring subjects’ cognitive systems and comparing subjects. In science education, studies have applied RGT for various purposes, which we categorized into three types: exploring individual cognitive systems, developing principles for teachers’ professional development, and evaluating the quality of textbooks. The limitations and validations of RGT are discussed in the final section of this paper.

(1) Background-How to solve the problem of forest farmers' choosing jobs after the implementation of the ecological compensation policies has become the key to realize the sustainable development of ecology and economy in the collective forest regions. (2) Methods-The research data came from the household survey conducted by the collective forest rights system reform monitoring project team in Shaanxi Province from July to August 2018, and 441 valid questionnaires were obtained. The OLS regression, intermediary effect model and propensity score matching method ( PSM) were used to analyze the relationship between ecological compensation policies, forest farmers' livelihood strategies and their income. (3) Results-From the perspective of direct effect, the impact of ecological compensation policies on forest farmers' income was significantly positive at the statistical level of 5%, and this effect was still significant after excluding ecological compensation samples or selecting only poverty-stricken counties as samples. From the perspective of mediating effect, the mediating effects of livelihood non-forestry and livelihood diversification on the impact of the ecological compensation policies on forest farmers' income were significant, and the mediating effect accounted for 15.58% and 19.08% respectively. From the perspective of heterogeneity of income effect, compared with those who did not participate in the policies, the total family forestry income of the forest farmers who participated in the policies decreased by 1544 yuan, but their non-forestry management income increased by 5881 yuan, non-forestry wage income increased by 4225 yuan. This indicated that after the forest farmers participated in the ecological compensation policies of public welfare forests, although they sacrificed part of the forest-land management rights to protect the ecological environment, which reduced their forestry income, they could change their livelihood strategies. The household surplus labor forces could increase their household income through non-forest employment and business activities in the secondary and tertiary industries. (4) Conclusions and Discussions-In order to improve the implementation performance of the ecological compensation policies for public welfare forests, the following policy suggestions are put forward : First, establish a dynamic adjustment mechanism for ecological compensation of public welfare forests, regularly monitor the management status of public welfare forests in poverty-stricken regions, and reward and punish them according to the monitoring results, so as to improve the initiative of the forest farmers' policy participation. Second, improve the supporting measures of the ecological compensation policies for public welfare forests and the environment for employment and entrepreneurship in forest areas. At the same time, encourage the forest farmers to rely on public welfare forests resources for employment or entrepreneurship to revitalize forestry resources. Third, strengthen the matching assistance for the forest farmers' livelihood transformation, appropriately guide the forest farmers to develop the forest undergrowth industry, or provide employment for the poor households and create more sources of livelihood for them. Fourth, encourage the transfer of forestland property rights of public welfare forests, guide the forest farmers to transfer the abandoned lands for public welfare forests to those individuals or units with higher management level, so as to promote the rational allocation of forestland resources and rural household labor resources. [ABSTRACT FROM AUTHOR]

Under-balanced drilling and under-balanced logging are very important techniques for directly identifying and protecting hydrocarbon reservoirs and enhancing productivity. The wellhead assembly under under-balanced logging is greatly different from that under conventional logging. Therefore, the length of cable electrode for dual laterolog should be reduced to adapt to the wellhead assembly, which causes the deep laterolog responses to drop and cannot truly reflect the reservoir property. The rule of electrode coefficient varying with the cable electrode length under under-balanced conditions has been computed using finite element method, that is, the longer the cable electrode, the smaller the electrode coefficient. The deep laterolog resistivity correction method under under-balanced condition is introduced. Field data examples are used to test the new method and shows that this method is reliable. This method can be used to any length of cable electrode and can be applied to field pretreatment directly. The corrected deep laterolog resistivity can be used in logging interpretation and quantitative hydrocarbon evaluation. Key words: under-balanced logging, hydrocarbon reservoir protection, dual laterolog, electrode coefficient, apparent resistivity correction, finite element method

There is a high toxicity and carcinogrenicity of aflatoxin B1 (AFB1) in food. Current detection of aflatoxin B1 is performed by a variety of methods including thin layer chromatography, high performance liquid chromatography, liquid chromatography-tandem mass spectrometry and immunoassay, but they all have some limitations. AFB1 detection research had obtained certain achievements based on nucleic acid aptasensor. The thee new detection technology based on the electrochemical nucleic acid aptasensor, optical nucleic acid aptasensor and PCR nucleic acid aptasensor had advantages and disadvantages. A new idea in which glucose meter was used as a detection instrument and combined with nucleic acid aptasensor for AFB1 qualitative analysis were to be experimental veried. Combining nucleic acid aptasensor with magnetic nanoparticle united with bio-recognition elements as the adsorbent for solid phase extraction (SPE) was expected to be a breakthrough in the future. [ABSTRACT FROM AUTHOR]

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According to the interpreted results of three satellite images of Dongzhai Harbour obtained in 1988, 1998 and 2009, the changes of landscape pattern and the differences of its driving forces of mangrove forest in Dongzhai Harbour were analyzed with a patch-based method on spatial distribution dynamics. The results showed that the areas of mangrove forest in 1988, 1998 and 2009 were 1809.4, 1738.7 and 1608.2 hm respectively, which presented a trend of decrease with enhanced degree of landscape fragmentation. The transformations among different landscape types indicated that the mangrove, agricultural land and forest land were mainly changed into built-up land and aquaculture pond. The statistical results obtained from three different methods, i.e., accumulative counting, percentage counting and main transformation route counting, showed that natural factors were the main reason for the changes of patch number, responsible for 58.6%, 72.2% and 72.1% of patch number change, respectively, while the percentages of patch area change induced by human activities were 70.4%, 70.3% and 76.4%, respectively, indicating that human activities were the primary factors of the change of patch areas. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of Annexin A2 and heat shock protein 27 (HSP27) in reducing porcine reproductive and respiratory syndrome virus (PRRSV) infection.

The article discusses a study on the purification and identification of Brucella abortus 544A O chain-A antigen using heat-phenol, agarose immunodiffusion (AGID) and sodium dodycyl sulfate polycrylamide gel electrophoresis (SDS-PAGE) and preparation of the strain specific monoclonal antibodies (McAbs).

The problem of matrix inequality is important in the matrix theory. With the Shur theorem of semi-positive definite matrices, some new results of norm inequality related to Rotefid trace inequality for some concave functions and arbitrary n x n matrix were given. Note that the theorems in the other paper are the corollaries in this paper, and the result of the inequalities involving Rotefid trace inequality can be to used to other fields. [ABSTRACT FROM AUTHOR]

The fly ash sample was characterized by size fraction, X-ray diffraction, contact angle measurements and X-ray fluorescence. The function of a new type of frother (KD) which can produce more stable foam than conventional frothers was studied. The effect of the column flotation operating variables on the removal of unburned carbon from the fly ash was also systematically examined. Within the range studied, the optimum frother dosage is 400 g/t, superficial gas velocity is 1. 8 cm/s, froth thickness is about 150-200 mm and circulating pressure is 0. 22 MPa. The results indicate that Cyclonic-Static Micro-bubble Flotation Column (FCSMC ) technique is effective in removing the unburned carbon from coal fly ash. Under the optimized conditions, a cleaning ash with 3. 15% LOI (Loss on Ignition) and 91. 88% RUC(Removal Rate of Unburned Carbon) is obtained. [ABSTRACT FROM AUTHOR]

Objective: To establish a method for simultaneous determination of 12 kinds of perfluorinated compounds (PFCs) in human urine based on ultra performance liquid chromatography tandem quadrupole linear ion trap mass spectrometry (UPLC-QTtrap-MS)., Methods: After pH adjustment with 2% formic acid, the urine samples were loaded on a WAX solid phase extraction (SPE) cartridge for extraction, purification and concentration. The eluates were collected, concentrated to dryness under nitrogen, and reconstituted with 10 mmol/L ammonium acetate aqueous solution-methanol ( V water ∶ V methanol = 70∶30) before injection. UPLC was performed on a C 18 cartridge, and methanol and 10 mmol/L ammonium acetate aqueous solution was used as mobile phases with gradient elution. QTtrap-MS was operated in multiple reaction monitoring (MRM) mode, and the internal standard calibration curves were applied for quantitative analysis., Results: Good linearity was obtained in the linear range, with the method detection limits and method quantification limits being 0.032 ng/L-6.5 ng/L and 0.10 ng/L-21 ng/L, respectively, for the 12 kinds of PFCs. The spiked recoveries of the 12 kinds of PFCs were 91.5%-114%, with the intra-day precision and the inter-day precision being 0.57%-16.0% and 1.88%-20.1%, respectively. The established method was applied to the determination of 12 kinds of PFCs in the urine samples of primary school students collected in one area. Nine kinds of PFCs were detected in the urine samples in this area. Among the PFCs detected, perfluorobutanesulfonic acid (PFBS) and perfluorooctanoic acid (PFOA) were the main PFCs found in the student urine samples., Conclusion: The method established in this study could be used to simultaneously examine 12 kinds of PFCs in urine. The method combined SPE with isotope internal standard correction and achieved good sensitivity and accuracy., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objective To screen a standard homogenous cDNA library of human gastric mucosal epithelium with yeast two-hybrid system and find the proteins that interact with Src-homology 2-containing inositol 5-phosphatase 2 (SHIP2). Methods Using the yeast two-hybrid system, P1 (SH2+5-Ptase) and P2 (PRD+SAM) segments of SHIP2 were used as bait proteins to screen the proteins that bind to SHIP2 from the homogenous cDNA library of human gastric mucosal epithelium. The selected interacting proteins of SHIP2 were verified by co-immunoprecipitation assay. Results A total of 39 positive clones were selected and sequenced for alignment analysis. It was verified that PHB interacted with SHIP2 by reductive hybridization and co-immunoprecipitation assays. Conclusion PHB, the interacting protein of SHIP2 was screened by yeast two-hybrid system from the homogenous cDNA library of human gastric mucosal epithelium.

The analytical method of nicotine and cotinine in human urine with hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS/MS) was established. After the urine sample containing nicotine-d 4 and cotinine-d 3 isotope internal standards being diluted with water, the filtrate was introduced into ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Separation was performed on an ACQUITY UPLC ® BEH HILIC column (50 mm×3.0 mm, 1.7 μ m), in which methanol and 0.1% (v/v) ammonia were used as the mobile phases with isocratic elution at 0.2 mL/min of flow rate. Positive ion scan mode was used for mass spectrometry measurement and calibration curves were plotted for quantification determination. A good linearity could be obtained in the range of 1.0-1000 μ g/L for nicotine and cotinine with the linear coefficients of 0.9949 and 0.9958, respectively. The limits of detection of nicotine and cotinine were 0.082 μ g/L and 0.077 μ g/L, and the limits of quantification were 0.27 μ g/L and 0.26 μ g/L, respectively. The recoveries of the spiked urine samples were 90.4%-103.5% and 93.0%-104.6%, and the relative standard deviations (RSDs) were 4.80%-6.21% and 4.22%-7.15% for nicotine and cotinine respectively. The established method was applied to the analyis of 200 urine samples. Based on the investigation information of the urine of the smoking people, the nicotine contents were 26.68-854.30 μ g/L, and the cotinine contents were 36.66-1191.18 μ g/L ( n =86, M nicotine =76.00 μ g/L, M cotinine =83.52 μ g/L, M :median); of the nonsmoking people, the nicotine contents were 5.08-69.66 μ g/L, and the cotinine contents were 3.16-28.21 μ g/L ( n =114, M nicotine =7.53 μ g/L, M cotinine =3.79 μ g/L). The method is simple, sensitive and rapid. It is suitable for batch analysis of nicotine and cotinine in urine, and it can meet the requirement of evaluating the human tobacco exposure.

In the present work, Eu2+/Dy3+ co-doped high silica glasses with different process parameters were prepared and the effect of critical process parameters including phase separation temperature, solution concentration and sintering temperature on the luminescence properties of Eu2+/Dy3+ co-doped high silica glasses was investigated by means of measuring pore surface parameters of porous glasses, emission spectra, infrared absorption spectra and densities of high silica glasses. Pore structure parameters of porous glass samples and emission spectra of corresponding high silica glass samples with different phase separation temperatures show that the phase separation temperature has indirect effect on luminescence properties of high silica glass by influencing specific surface area value of corresponding porous glass. Specific surface area of porous glass changes when phase separation temperature changes. High silica glass achieves maximum emission intensity when the maximum specific surface area of porous glass is obtained. Luminescence intensity of high silica glass increases when specific surface area of porous glass increases. Emission spectra of high silica glass samples with different solution concentrations show that the emission intensities of Eu2+ and Dy3+ in high silica glass are enhanced with the increase in the Dy3+ concentration in solution; when the Dy3+ concentration is beyond 0.1 mol x L(-1), the emission intensities of Eu2+ and Dy3+ in high silica glass are both decreased due to the occurring of concentration quench of Dy3+ in the glass. Emission spectra and infrared absorption spectra of high silica glass samples with different sintering temperatures show that the emission intensity of high silica glass is increased with the increase in the sintering temperature because the content of residual hydroxyl groups -OH in the glass is decreased; when the sintering temperature is beyond 1000 degrees C, the high silica glass exhibits crystalline and the luminescence intensity decreases.

Objective: To study the frequency of a 9 bp deletion polymorphism of mitochondrial DNA (mtDNA) in ethnic Miao, Buyi and Dong populations from Guizhou province., Methods: Polymerase chain reaction-polyacrylamide gel electrophoresis (PCR-PAGE) was used to detect the 9 bp deletion. The result was verified with DNA sequencing., Results: Two polymorphisms, including a standard pattern and a short pattern (the 9 bp deletion), were found among the three ethnic groups. The frequency of short pattern in 304 males was 23.0%. Respectively, those of Miao, Buyi and Dong ethnics were 28.6%, 26.8% and 13.7%. A statistically significant difference was detected among the three groups (P<0.05)., Conclusion: The frequencies of the 9 bp polymorphism were relatively high among ethnic Miao, Buyi and Dong populations from Guizhou, and there was a significant difference between the three.

Objective: To examine the relationship between cigarette smoking and body mass index (BMI) as well as waist circumference (WC) of men from 9 rural districts of Hanzhong, Shaanxi province., Methods: Cross-sectional data was analyzed from Hanzhong Health Survey on rural residents in 2010. Quantile regression mode was used to compare the results using the BMI (WC) and smoking status (degree) as the dependent variables and independent variable and confounding factors were also controlled., Results: 1039 male residents of rural areas of Hanzhong city were investigated. The prevalence rates on overweight and obesity among the males were 28.0% and 5.9%, with central obesity as 35.0% and the rate of current cigarette smoking was 63.6% in the areas., Results: from the quantile regression showed that the relationship between smoking status and BMI beyond 80 percentile in men (BMI = 24.4) which was not significantly different BMI among the heavy smokers, was much higher than those mild smokers beyond 90 percentile (BMI = 24.9). WC of the current smokers was significantly higher than those ex-smokers beyond the 95 percentile (WC = 96.7 cm). WCs of the moderate and heavy smokers had an increase along with the increase of WCs beyond the 85 percentiles (WC = 89.9 cm)., Conclusion: The effect of smoking status and BMI (WC) were inconsistent, however, with BMI and WC increased among the subjects whose BMI or WC were at the high extreme end of the distribution. Thus, we should advise the obese subjects to quit smoking.

Objective: The objective of this study was to investigate the prevalence rate of abdominal obesity and to explore the associated risk factors in rural communities from Hanzhong area, Shaanxi province, and to provide baseline data for further targeted intervention programs., Methods: A cross-sectional study was conducted among all the participants with questionnaires, interview and physical examination. Nine townships were selected in Hanzhong area, followed by one village randomly chosen from the selected township, using the stratified random sampling method., Results: There were 3030 participants in this survey, among which 3021 samples were valid, including 1048 males and 1973 females. The overall prevalence rate of abdominal obesity was 38.9% (standardized rate as 33.4%) in rural communities of Hanzhong, and the prevalence rate on males abdominal obesity (35.0%) was significantly lower than that of females (40.9%). It was found that following factors as: being male, married, having more household wealth, frequent consumption of fried food, non-engagement of agricultural labor work, being nonsmoker or ex-smoker, spending longer time on watching-TV etc. were positively associated with the bigger odds of having abdominal obesity when using the logistic regression analysis. Meanwhile, data from this study indicated that factors as: at younger age, frequent participation in agricultural labor, under artificial feeding, with more years of education, less frequency of pregnancy etc. were negatively related to the prevalence of female abdominal obesity., Conclusion: The prevalence rate of abdominal obesity in Hanzhong area, Shaanxi province was significantly higher than the national average level which called for the development of related intervention programs to prevent chronic diseases associated with gender related-obesity in Hanzhong.

Objective: To develop a method for the rapid determination of ethanol in blood with capillary-GC., Methods: 0.50 mL of whole blood sample was taken and added with 1.00 mL of dimethyl sulfoxide (DMSO), and 2 g of anhydrous sodium sulfate. The supernatant of the sample solution was directly injected into GC for analysis., Results: Ethanol was separated from other substances in the sample. The liner range of ethanol detected by the capillary-GC was 0.0-300.0 mg/100 mL, and the detection limit was 0.2 mg/100 mL. The RSD for standard solution determination was 1.36%. Satisfactory results were obtained for the determination of ethanol in whole blood samples, with recoveries ranging from 90.9% to 107.3% and a RSD of 1.98%. The combined uncertainty was 2.2%., Conclusion: This is a rapid, sensitive and simple method for determination of ethanol in large quantities of samples. The method has shortened the duration of analysis cycle in comparison with the traditional headspace-GC, with a reduction from 20-30 min to less than 10 min.