中国冰雪生态系统服务框架构建及价值评估

针对目前对生态系统服务价值的研究主要集中在森林、草地、湿地等自然生态系统,而很少关注冰雪生态系统服务价值的问题,构建了冰雪生态系统服务框架及价值评估体系,划分东北、华北、西北、西南4大区域,在MODIS、统计数据和气象站数据的基础上,基于功能量法,建立基于3个一级服务、8个二级的冰雪服务体系,对中国冰雪生态系统的供给服务、调节服务和文化服务价值进行核算。结果表明,中国冰雪生态系统总值为81207.93亿元,其中,东北、华北、西北、西南分别为11314.41、17020.52、31030.5、21842.5亿元,分别占总价值的13.93%、21.11%、38.22%、26.74%;从冰雪生态系统服务价值对比来看,气候调节>调节径流>文化服务>供给服务>农田防旱>土壤保熵>空气加湿>大气净化。

简易胃肠功能量表评估法在重症急性胰腺炎肠内营养耐受性的应用价值

目的:探讨简易胃肠功能量表评估法对重症急性胰腺炎肠内营养不耐受的应用价值,为寻找重症急性胰腺炎肠内营养不耐受诊断的简易方法提供依据。方法:随机抽取随机抽取2017年1月至2020年6月在我院治疗、符合纳入排除标准的重症胰腺炎行肠内营养的患者80例进行回顾性研究,其中发生耐受性的35例、未发的45例,所有患者均采用简易胃肠功能量表评估法和常规症状评估方法进行评估,采用统计学方法比较两者的诊断价值及所用时间。结果:(1)简易胃肠功能量表评估法与常规方法阳性诊断率比较差异无统计学意义,P>0.05;但所用时间低于常规方法,差异有统计学意义,P<0.05;(2)简易胃肠功能量表评估法和常规观察ROC曲线下面积差异无统计学意义,Z=0.211,P=0.582。结论简易胃肠功能量表评估法和常规方法具有相同的诊断价值,但其所用时间较短,值得临床推广应用,但本研究是基于小样本量的研究,其可靠性尚需进一步扩大样本进行证实。

Measurement of hepatic functional mass by means of ^(13)C-methacetin and ^(13)C-phenylalanine breath tests in chronic liver disease: Comparison with Child-Pugh score and serum bile acid levels

AIM: To evaluate and compare the clinical usefulness of 13C-phenylalanine and 13C-methacetin breath tests in quantitating functional hepatic mass in patients with chronic liver disease and to further compare these results with those of conventional tests, Child-Pugh score and serum bile acid levels.METHODS: One hundred and forty patients (50 HCV-related chronic hepatitis, 90 liver cirrhosis patients) and 40 matched healthy controls were studied. Both breath test and routine liver test, serum levels of cholic and chenodeoxycholic acid conjugates were evaluated.RESULTS: Methacetin breath test, expressed as 60 min cumulative percent of oxidation, discriminated the hepatic functional capacity not only between controls and liver disease patients, but also between different categories of chronic liver disease patients. Methacetin breath test was correlated with liver function tests and serum bile acids.Furthermore, methacetin breath test, as well as serum bile acids, were highly predictive of Child-Pugh scores. The diagnostic power of phenylalanine breath test was always less than that of methacetin breath test.CONCLUSION: Methacetin breath test represents a safe and accurate diagnostic tool in the evaluation of hepatic functional mass in chronic liver disease patients.

Quantitative Surface Chirality Detection with Sum Frequency Generation Vibrational Spectroscopy： Twin Polarization Angle Approach

Here we report a novel twin polarization angle （TPA） approach in the quantitative chirality detection with the surface sum-frequency generation vibrational spectroscopy （SFG-VS）. Generally, the achiral contribution dominates the surface SFG-VS signal, and the pure chiral signal is usually two or three orders of magnitude smaller. Therefore, it has been difficult to make quantitative detection and analysis of the chiral contributions to the surface SFG- VS signal. In the TPA method, by varying together the polarization angles of the incoming visible light and the sum frequency signal at fixed s or p polarization of the incoming infrared beam, the polarization dependent SFG signal can give not only direct signature of the chiral contribution in the total SFG-VS signal, but also the accurate measurement of the chiral and achiral components in the surface SFG signal. The general description of the TPA method is presented and the experiment test of the TPA approach is also presented for the SFG-VS from the S- and R-limonene chiral liquid surfaces. The most accurate degree of chiral excess values thus obtained for the 2878 cm^-1 spectral peak of the S- and R-limonene liquid surfaces are （23.7±0.4）% and （-25.4±1.3）%, respectively.

Nonlinear Mixed-Effects Models for Repairable Systems Reliability

Mixed-effects models,also called random-effects models,are a regression type of analysis which enables the analyst to not only describe the trend over time within each subject,but also to describe the variation among different subjects.Nonlinear mixed-effects models provide a powerful and flexible tool for handling the unbalanced count data.In this paper,nonlinear mixed-effects models are used to analyze the failure data from a repairable system with multiple copies.By using this type of models,statistical inferences about the population and all copies can be made when accounting for copy-to-copy variance.Results of fitting nonlinear mixed-effects models to nine failure-data sets show that the nonlinear mixed-effects models provide a useful tool for analyzing the failure data from multi-copy repairable systems.

Clinical observation on therapeutic effect of acupuncture for chronic functional constipation

Methods Two Qihai （气海 CV Objective To discuss the efficacy of acupuncture for groups of points were applied alternatively to 90 cases by chronic functional constipation acupuncture： （1） Tianshhu （CFC）. ST 25）, 6）, Shemgjfuxu （上巨虚 ST 37）, etc. （2）Zhongliao （中髎 BL 33）, Xiadiao （下髎 BL 34）, Dachangshu （大肠俞 BL 25）, etc. Electroacupuncture was applied in combination at Zhongliao （中髎 BL 33）, Xialiao （下髎 BL 34）, Tianshu（天枢 ST 25） and Shamgjuxu （上巨虚 ST 37）, once a day, 10 treatments made one session. By constipation diary of patients, frequency of going to stool, straining severity, time of once bowl evacuation, a sense of incomplete bowel emptying, stool quality, a sense of defecation and the Patient Assessment of Constipation Quality of Life questionnaire （PAC-QOL）, as well as the changes before and after treatment were observed. Results After treatment, the apparent improvements were achieved in frequency of going to stool, straining severity, time of once bowl evacuation, a sense of incomplete bowel emptying, a sense of defecation and score of PAC-QOL as compared with those before treatment （all P〈0.01）. The total effective rate was 67.7% （61/70）. The acupuncture effieacies were various on CFC of different dynamic mechanisms. The efficacy on slow transit constipation （STC） was superior to that caused by spastic pelvic floor syndrome （SPFS-C） （P〈0.05）, the efficacy on constipation caused by irritable bowel syndrome （IBS-C） was superior to that on either SPFS-C or constipation caused by relaxant pelvic floor syndrome （RPFS-C） （both P〈0.05）. Of 52 eases in effective follow-up, 1 month after treatment, 3 eases were cured, 6 eases markedly effective, 23 eases effective, and 20 cases failed; 3 months after treatment, 3 eases were cured, 5 eases markedly effective, 16 cases effective and 28 cases failed. Conclusion Acupuncture has definite efficacy on CFC with definite etiology, loci and diagnostic classification. But, the efficacies are different due to various dynamic mechanisms. A further optimized treatment program is required to improve the efficacy on SPFS-C and RPFS-C.

Review of Methods to Quantify Trade-offs among Ecosystem Services and Future Model Developments

Ecosystem services are spatially heterogeneous and temporal variability, which results in trade-offs,synergies and neutrality. The trade-off is a key problem in ecosystem management and requires optimized decision-making research. This paper reviews methods for identifying trade-offs and suggest future model developments. We conclude that(1) ecosystem service assessment depends on quantitative indicators and its modeling;(2)scenario analysis, multi-objective analysis and production possibility boundary are an effective means of ecosystem service trade-off decision-making;(3) future research needs to strengthen ecosystem service supply and demand flow and assist decision-making ecosystem mapping. Finally, integrated models should be developed to simulate and diagnose different scenarios and to optimize measures in land and ecosystem management for sustainability.

Synthesis of multifunctional monomers from rosin for the properties enhancement of soybean-oil based thermosets

Two kinds of rosin derivatives, （2-hydroxy-3-（methacryloyloxy）propyl 7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a- decahydrophenanthrene-1-carboxylate） （HMPIDDC） and （（（7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octahydrophenan- thren-1-yl）methyl）azanediyl）bis（2-hydroxypropane-3,1-diyl）bis（2-methylacrylate） （IDOMAHM） were synthesized under mild and easy to implement conditions. The two derivatives were employed as the rigid monomers to copolymerize with acrylated epoxidized soybean oil （AESO）, as so to improve the performance of the cured resins. The chemical structures of HMPIDDC and IDOMAHM were confirmed by nuclear magnetic resonance （NMR） and Fourier Transform Infrared （FT-IR） before copolymerization. The curing behaviors of pristine AESO, AESO/HMPIDDC blend, and AESO/IDOMAHM blend were monitored by differential scanning calorimetry （DSC）. Moreover, the thermal and mechanical properties of the cured resins were evaluated by universal mechanical testing, dynamic mechanical analysis （DMA） and thermogravimetric analysis （TGA）. The results demonstrated that after the introduction of HMPIDDC and IDOMAHM, the glass transition temperature and mechanical properties of the copolymerized resin were significantly increased. In one word, HMPIDDC and IDOMAHM showed dramatic potential to be used as bio-based compounds to improve the properties of soybean-oil based thermosets.

Theoretical methods for excited state dynamics of molecules and molecular aggregates

This contribution provides a summary of proposed theoretical and computational studies on excited state dynamics in molecular aggregates, as an important part of the National Natural Science Foundation (NNSF) Major Project entitled "Theoretical study of the low-lying electronic excited state for molecular aggregates". This study will focus on developments of novel methods to simulate excited state dynamics of molecular aggregates, with the aim of understanding several important chemical physics processes, and providing a solid foundation for predicting the opto-electronic properties of organic functional materials and devices. The contents of this study include: (1) The quantum chemical methods for electronic excited state and electronic couplings targeted for dynamics in molecular aggregates; (2) Methods to construct effective Hamiltonian models, and to solve their dynamics using system-bath approaches; (3) Non-adiabatic mixed quantum-classic methods targeted for molecular aggregates; (4) Theoretical studies of charge and energy transfer, and related spectroscopic phenomena in molecular aggregates.