Meta分析中连续性变量二分化后的效应量估计

背景:无论在医学研究领域以及行为科学或心理学研究领域,即使是设计类型为两组样本的比较研究,当对同一研究结局变量有的采用二分类变量,有的采用连续性变量,特别是研究结局实质上为连续性变量但在分析时采用二分类化处理这种情况时,在进行Meta分析时,也面临着巨大挑战。目的:基于2×2列联表的形式探讨采用7种不同的效应量指标对结局变量实质上为连续性变量却被二分类化的总体标准化均差效应量(δ)的估计效能。方法:应用计算机检索CNKI全文数据库、维普全文数据库、万方中国博硕数据库(检索年限:1990/2009)及Pubmed数据库(检索年限:1979/2009)有关组间比较研究结局变量为连续性、二分类以及连续性与二分类混合型研究的Meta分析或系统评价方法学文献,中文检索词为"组间比较研究,连续性结局,二分类结局,合并的连续性与二分类结局,Meta分析,效应量";英文检索词为"group comparison study,continuous outcomes,dichotomous outcomes,combining continuous and dichotomous outcomes,meta-analysis,effect size"。排除非比较性研究以及相关的Meta分析与系统评价文献。结果与结论:符合标准的23篇文献主要探讨了两组比较研究中结局变量为连续性测量变量的效应量选择与连续性变量二分化处理7种效应量选择问题。在社会学与行为学研究领域,实质上为连续性结局变量为了解释与使用方便而在分析时采用了二分类化处理的情况比较普遍,但给系统评价与Meta分析带来了挑战,针对实质上为连续性变量二分类化处理的情况,文章比较分析了7种常用的效应量,结果表明两种效应量指标是一种不错的选择,一种是基于probit转换而另一种是基于logistic分布。

“规范二分化”下的一事不再理:基于程序安定的考量

一事不再理的涵义和作用机理需要明确。通过与既判力、重复诉讼的比较可厘清一事不再理的涵义。"规范二分化"下一事不再理的作用机理是:作为行为规范,其根据当事人、诉的声明及主要争点联动识别"一事",使对"一事"的再诉因取效不能而被驳回;作为评价规范,其基于程序安定的法经济学考量,因势制宜地对"二同"下不同类型的"一事"给予反诉、合并、中止的评价。

3D seismic forward modeling from the multiphysical inversion at the Ketzin CO_(2) storage site

From June 2008 to August 2013,approximately 67 kt of CO_(2) was injected into a deep saline formation at the Ketzin pilot CO_(2) storage site.During injection,3D seismic surveys have been performed to monitor the migration of sequestered CO_(2).Seismic monitoring results are limited by the acquisition and signal-to-noise ratio of the acquired data.The multiphysical reservoir simulation provides information regarding the CO_(2) fluid behavior,and the approximated model should be calibrated with the monitoring results.In this work,property models are delivered from the multiphysical model during 3D repeated seismic surveys.The simulated seismic data based on the models are compared with the real data,and the results validate the effectiveness of the multiphysical inversion method.Time-lapse analysis shows the trend of CO_(2) migration during and after injection.

Skin brightening benefit of 4-hexylresorcinol in vivo and in vitro and its underlying mechanism

4-Hexylresorcinol(4-HR),a potent tyrosinase inhibitor,has been used as an even-tone active ingredient for skin care application since 2007.While the skin brightening efficacy of 4-HR in Chinese population has not been thoroughly investigated and its significance in keratinocytes has not been fully raveled.This study aims to evaluate the skin brightening potential of 4-HR in vivo and in vitro and explore its new mechanism of action through transcriptome approach.The skin brightening effect of 0.4%4-HR in a facial serum was assessed in an 8-week,double-blinded,placebo-controlled,and randomized clinical study in 67 Chinese participants.ITA°,melanin index(MI)and visual grading were measured at baseline and 2,4 and 8 weeks after use.A pigmented living skin equivalent(pLSE)model constructed from Asian skin cells was utilized to assess the brightening efficacy of 0.4%4-HR by measuring the model’s brightness(L^(*)value)and melanin content.Then,transcriptomic analysis of 4-HR treated human epidermal keratinocytes was conducted,and the two in vitro models were adopted for hypothesis validation afterwards.In the clinical study,the result shows both 0.4%4-HR serum and placebo chassis can significantly improve all measures as compared to baseline at the 2,4,and 8 weeks.Furthermore,0.4%HR serum demonstrates a better performance in increasing ITA°as early as 2 weeks of application and decreasing MI value than the placebo group at Week 2.In the pLSE model,0.4%4-HR with topical application evidently increases L^(*)value by 15.88%and decreases melanin content by 47.61%compared to UVB group.RNA-sequencing analysis implies that 4-HR can regulate multiple biological processes including skin development,keratinocyte differentiation,oxidant activity and autophagy function.In the blue-light challenged human keratinocytes model,4-HR shows a significant ROS suppression capacity.In the keratinocytes-melanocytes co-culture model,4-HR prompts autophagy activity and decreases melanin content.Most importantly,the melanin inhibitory activity of 4-HR is compromised after co-treating with Chloroquine,an autophagy inhibitor,suggesting autophagy regulation property of 4-HR may partially contribute to its skin brightening efficacy.Taken together,these data demonstrate skin brightening efficacy of 0.4%4-HR in vivo and in vitro,in addition to acting as a tyrosinase inhibitor,4-HR can contribute to skin brightening benefit via enhancing cellular antioxidant capacity and autophagy activation.

A New Diterpenoid from Aralia fargesii

Four diterpenoids, including a new ent-kaurane diterpene (1), were isolated from the rhizome of Aralia fargesii Franch. On the basis of chemical and spectral evidence (IR, EI-MS, HREI-MS, H-1-NMR, C-13-NMR and HMQC), the structure of compound 1 was established to be 17-acetoxy-16alpha-ent-kauran-19-oic acid The other three known compounds were identified as ent-pimera-8(14) 15-dien-19-oic acid (2), 16alpha-hydroxy-( -)-kauran-19-oic acid (3) and 16alpha-17-dihydroxy-ent-kauran-19-oic acid (4). The three known diterpenoids were obtained from this plant for the first time.

NH_3 selective catalytic reduction of NO: A large surface TiO_2 support and its promotion of V_2O_5 dispersion on the prepared catalyst

A titania support with a large surface area was developed, which has a BET surface area of 380.5 m^2/g, four times that of a traditional titania support. The support was ultrasonically impregnated with 5 wt% vanadia. A special heat treatment was used in the calcination to maintain the large surface area and high dispersion of vanadium species. This catalyst was compared to a common V2O5-TiO2 catalyst with the same vanadia loading prepared by a traditional method. The new catalyst has a surface area of 117.7 m^2/g, which was 38% higher than the traditional V2O5-TiO2 catalyst. The selective catalytic reduction（SCR） performance demonstrated that the new catalyst had a wider temperature window and better N2 selectivity compared to the traditional one. The NO conversion was 80% from 200 to 450 °C. The temperature window was 100 °C wider than the traditional catalyst. Raman spectra indicated that the vanadium species formed more V-O-V linkages on the catalyst prepared by the traditional method. The amount of V-O-Ti and V=O was larger for the new catalyst. Temperature programmed desorption of NH3, temperature programmed reduction by H2 and X-ray photoelectron spectroscopy results showed that its redox ability and total acidity were enhanced. The results are helpful for developing a more efficient SCR catalyst for the removal of NOx in flue gases.

Oxidation of Carbon Supports at Fuel Cell Cathodes： Differential Electrochemical Mass Spectrometric Study

The effects of O2 and the supported Pt nano-particles on the mechanisms and kinetics of the carbon support corrosion are investigated by monitoring the CO2 production using differential electrochemical mass spectrometry in a dual-thin layer flow cell. Carbon can be oxidized in different distinct potential regimes; O2 accelerates carbon oxidation, the rates of CO2 production from carbon oxidation in O2 saturated solution are two times of that in N2 saturated solution at the same potential; Pt can catalyze the carbon oxidation, with supported Pt nanoparticles, the overpotential for carbon oxidation is much smaller than that without loading in the carbon electrode. The mechanism for the enhanced carbon oxidation by Pt and O2 are discussed.

Study on preparation of In_2O_3 superfine powder via polymer-network process

Nanocrystalline,single-phase undoped In 2O 3 was prepared by a polymer-network synthesis technique with indium nitrate as the starting material;several methods such as X-ray diffractometry (XRD) and transmission electron microscopy (TEM) were employed to obtain detailed information on the crystallography and microstructual appearance of In 2O 3 superfine powders. The influence of the concentration of starting solution,calcination temperature and time on the particle size was also that investigated by means of the XRD patterns. Results indicate that the obtained powders are mostly crystalline single phase with uniform size and also that the size of the products can be controlled under proper condition.

Dynamics of profiles and storage of carbon dioxide in broadleaved/Korean forest in Changbai Mountain

CO2 concentrations at different heights in a broadleaved/Korean forest (with a mean height of 26 m) were measured with infrared gas analyzer IRGA (model 2250D, LI-COR Inc. and LI-COR, 820) from Aug. to Oct. of 1999, Apr. to Jul. of 2000, and from Aug. 2002 to Sept. 2003. Based on the collected dada, the diurnal and seasonal dynamics of profiles and storage of carbon dioxide in the forest were analyzed. The diurnal CO2 profiles showed that the vertical distribution of CO2 concentration were different for daytime and nighttime, and the CO2 concentration was highest close to forest floor, no matter at daytime and nighttime. The seasonal profiles of CO2 showed that stratification in the canopy was evident during growth season. CO2 concentrations at different heights (60 m to 2.5 m) had a little change in March, with a difference of 10 mmolmol-1, but had a significant change in July, with a difference of 60 mmolmol-1. In July, there also existed a greater gradient of CO2 concentrations at canopy (22, 26 and 32 m), with a difference of 8 mmolmol-1. The calculated total storage (ΔC/Δt ) of CO2 in the air column with height of 40 m beneath eddy covariance instrument was negative, and made a little contribution to NEE.

Low temperature molten salt synthesis of porous La_(1-x)Sr_xMn_(0.8)Fe_(0.2)O_3(0≤x≤0.6) microspheres with high catalytic activity for CO oxidation

A molten salt method was developed to prepare porous La1‐xSrxMn0.8Fe0.2O3 （0≤ x ≤ 0.6） micro‐spheres using hierarchical porous δ‐MnO2 microspheres as a template in eutectic NaNO3‐KNO3. X‐ray diffraction patterns showed that single phase LaMn0.8Fe0.2O3 with good crystallinity was syn‐thesized at 450℃ after 4 h. Transmission electron microscope images exhibited that the LaMn0.8Fe0.2O3 sample obtained at 450？？ after 4 h possessed a porous spherical morphology com‐posed of aggregated nanocrystallites. Field emission scanning electron microscope images indicated that the growth of the porous LaMn0.8Fe0.2O3 microspheres has two stages. SEM pictures showed that a higher calcination temperature than 450？？ had an adverse effect on the formation of a po‐rous spherical structure. The LaMn0.8Fe0.2O3 sample obtained at 450？？ after 4 h displayed a high BET surface area of 55.73 m2/g with a pore size of 9.38 nm. Fourier transform infrared spectra suggested that Sr2＋ions entered the A sites and induced a decrease of the binding energy between Mn and O. The CO conversion with the La1‐xSrxMn0.8Fe0.2O3 （0≤x≤0.6） samples indicated that the La0.4Sr0.6Mn0.8Fe0.2O3 sample had the best catalytic activity and stability. Further analysis by X‐ray photoelectron spectroscopy demonstrated that Sr2＋doping altered the content of Mn4＋ions, oxygen vacancies and adsorbed oxygen species on the surface, which affected the catalytic performance for CO oxidation.

Possible emissions of N_2O from plants in coniferous-deciduous mixed forests

Aboveground vertical profiles of N2O concentrations were measured with in two natural coniferous-deciduous mixed forests of 1998 and 1999 in Changbai M ountain. Significant high N2O concentrations were found in six profiles out of t welve profiles. The results showed that high concentrations were 3.03% to 64.9% higher than the "normal concentrations" in these six profiles. Differences betwe en the high concentrations and the "normal concentrations" were statistically si gnificant. The simultaneous occurrence of high concentrations at/nearby the cano py height and normal concentrations at the trunk space height indicated an efflu x of N2O from foliage to atmosphere. This study afforded evidence supporting tha t plant per se, besides forest soil, was an important source of atmospheric N2O in a forest ecosystem.

Cloning,Sequencing and Molecular Phylogenetic Analysis of the Mitochondrial Cytochrome Oxidase Ⅰ Gene of Chilo suppressalis

[Objective] The research aimed at cloning and analyzing mitochondrial cytochrome oxidase I gene（cox 1）of C.suppressalis.[Method] The mitochondrial cox 1 gene of C.suppressalis was cloned with PCR method and sequenced.Then,cox1 sequences of other 21 Lepidopteran species were obtained by blasting the GenBank with cox 1 gene sequence of C.suppressalis.Finally,homology comparison and molecular phylogenitic analysis among the 22 Lepidopteran species were conducted.[Result] The open reading frame of cox 1 gene from C.suppressalis contained 1 531 nucleotides encoding a putative protein of 510 amino acids.The cox1 gene used a start codon CGA,and an incomplete termination codon composed of only T.Based on the amino acid sequences of cox 1,the molecular phylogenetic tree of Lepidoptera was reconstructed using the maximum likelihood（ML）method.The molecular phylogenetic tree was similar to the morphological phylogenetic tree mainly,but also showed some differences.[Conclusion] The result will provide reference for further research on expression and application of cox 1 gene.

Effect of TPB on curing reaction of HTPB-TDI

Catalysis effect of triphenyl bismuth （TPB） on kinetics of hydroxyl terminated polybutadiene-toluene diisocyanate （HTPB-TDI） curing reaction was studied by non-isothermal differential scanning calorimetry （DSC）. The characteristic temperature of curing system was measured for calculating kinetic parameters and establishing curing reaction kinetic equations. The results show that activation energy （Ea） of uncatalyzed HTPB-TDI curing system is 51.29 kJmol-1, and TPB decreases Ea to 46.43 kJ＇mol-1. Catalyst lowers reaction temperature and shortens curing time through decreasing ac- tivation energy of curing reaction and accelerating reaction rate. TPB can increase the reaction rate at 27 ℃ to the value of uncatalyzed system at 80 ℃. The catalytic activity reaches the maximum when concentration is 0.5 %.

Visible-light photocatalytic selective aerobic oxidation of thiols to disulfides on anatase TiO2

This work presents the visible-light photocatalytic selective oxidation of thiols to disulfides with molecular oxygen(O2) on anatase TiO2. The high specific surface area of anatase TiO2 proved to be especially critical in conferring high photocatalytic activity. Herein, surface complexation between thiol and TiO2 gives rise to photocatalytic activity under irradiation with 520 nm green light-emitting diodes(LEDs), resulting in excellent reaction activity, substrate scope, and functional group tolerance. The transformation was extremely efficient for the selective oxidation of various thiols, particularly with substrates bearing electron-withdrawing groups(reaction times of less than 10 min). To date, the longest wavelength of visible light that this system can utilize is 520 nm by the surface complex of substrate-TiO2. Importantly, O2 was found to act as the electron and proton acceptor, rather than to incorporate into the substrates. Our findings regarding this surface complex-based photocatalytic system can allow one to understand the interaction between the conduction band electrons and O2.

GC/MS analyses of fractionated extraction of Shenfu coal with CS2,n-hexane,benzene

Shenfu coal was extracted with 0S2, n-hexane, benzene sequentially. The extracts were analyzed with GC/MS. It is presented that group seperation of soluble organic compounds in the coal can be achieved by fractionated extraction using different solvents. Main components in CS2 soluble fraction from Shenfu coal are alkyl-substituted arenes. Aliphatic hydrocarbons are overwhelmingly predominant in n-hexane-soluble fraction. Dito tricyclic aramatic hydrocarbons are identified in benzene-soluble fraction. The molecular structures detection of 2, 4, 6-trichlorobenzenamine and 3, 3＇, 4, 4＇, 5, 5＇-hexachloro-1, 1＇- biphenyl and 2-chlorocyclohexanol firstly provide information for existence form of chlorine in coal.

Photodissociation Dynamics of Carbon Dioxide Cation via the Vibrationally Mediated A^2Hu,1/2 State： A Time-Sliced Velocity-Mapped Ion Imaging Study

We report on the photodissociation dynamics of CO2^＋ via its A2Пu,1/2 state using the scheme of [1＋1] photon excitation that is intermediated by the mode-selected A2Hu,1/2（Vl,V2,0） vibronic states. Photodissociation fragment exciation spectrum and images of photofragment CO＋ have been measured to obtain reaction dynamics parameters such as the available energy and the average translational energy. Combining with the potential energy functions of CO2^＋, the dissociation mechanism of CO2^＋ is discussed. The conformational variation of CO2^＋ from linear to bent on the photodissociation dynamics of CO2^＋ is verified.

Supramolecular Fixation of Three Amines using Cobalt Tetraphenyl- porphyrin for SO2 Removal

In this work, supramolecular fixation of three amines, including aniline, ethylenediamine, and diethylamine, using cobalt tetraphenylporphyrin （CoTPP） for SO2 removal was studied using UV-Vis and fluorescence measurements. The UV-Vis spectra showed that increasing amines concentrations resulted in bathochromic shift for CoTPP Soret absorption band （B band）. Once SO2 was introduced, it competed with CoTPP for aniline, ethylenediamine, and diethylamine, which eventually led to the release of CoTPP and the change of solution colour/absorption band. After that, the CoTPP was regenerated and got back to the first state. The fluorescence spectra offered that CoTPP interacted with aniline, ethylenediamine, and diethylamine to form 1：1 molecular adducts. The interactions of CoTPP with aniline, ethylenediamine, and diethylamine were entropy-driven. The interaction of CoTPP with aniline and diethylamine was endothermic, and that with ethylenediamine was exothermic. Ethylenediamine presented a stronger binding constant value for CoTPP, so it was considered as a potential agent for SO2 removal.

Direct Synthesis of Dimethyl Carbonate from CO_2 and CH_3OH Using 0.4nm Molecular Sieve Supported Cu-Ni Bimetal Catalyst

The 0.4 nm molecular sieve supported Cu-Ni bimetal catalysts for direct synthesis of dimethyl carbonate (DMC) from CO 2 and CH 3 OH were prepared and investigated. The synthesized catalysts were fully characterized by BET, XRD (X-ray diffraction), TPR (temperature programmed reduction), IR (infra-red adsorption), NH 3-TPD (temperature programmed desorption) and CO 2-TPD (temperature programmed desorption) techniques. The results showed that the surface area of catalysts decreased with increasing metal content, and the metals as well as Cu-Ni alloy co-existed on the reduced catalyst surface. There existed interaction between metal and carrier, and moreover, metal particles affected obviously the acidity and basicity of carrier. The large amount of basic sites facilitated the activation of methanol to methoxyl species and their subsequent reaction with activated carbon dioxide. The catalysts were evaluated in a continuous tubular fixed-bed micro-gaseous reactor and the catalyst with bimetal loading of 20% (by mass) had best catalytic activities. Under the conditions of 393 K, 1.1 MPa, 5 h and gas space velocity of 510 h 1 , the selectivity and yield of DMC were higher than 86.0 % and 5.0 %, respectively.

The Effect of As_2O_3 on the Epression of Drugresistance Molecule in Malignant Neoplasmas

Objective: To detect the action of arsenic trioxide (As_2O_3) on theexpression of Tumor drug-resistant molecule. Methods: APL cell line MR_2 resistant to all-transretin-oic acid (ATRA ) was put into research, while APL cell line NB_4 was used for control. Theim-munocytochemical assays were used to detect the expressions of P-glycoprotein (P_(gp)) andGluta-thione S-transferase ( GST) . Results: Not only the expression of P_(gp) in MR_2 cell line(30%-40%) was significantly higher than that in NB4 cell line (10%-20% ) (P < 0.001), but also theexpression of GST in MR_2 cell line (60. 4 +- 4.0 )-( 66.5 +- 4.4) was significantly higher thanthat in NB4 cell line (28.3 +- 5.6)-(31.2 +- 5. l)(P < 0.05). As_2O_3 at the concentration of0.5-2.0 μmol/l could significantly decrease the expression of P_(gp) and GSTπ, but could donothing about the expression of GSTα and GSTμ. Conclusion: The lower expression of P_(gp) andGSTπ might be the sensitive indications of frustrating drug-resistance, while GSTα and GSTμ mightnot be the case. ATRA might be the substrates of P_(gp) transmission and GSTπ catalysis .

Recent advances and perspectives in cobalt‐based heterogeneous catalysts for photocatalytic water splitting,CO_(2) reduction,and N_(2) fixation

Solar‐driven conversion of carbon dioxide,water and nitrogen into high value‐added fuels(e.g.H_(2),CO,CH_(4),CH_(3)OH,NH_(3) and so on)is regarded as an environmental‐friendly and ideal route for relieving the greenhouse gas effect and countering energy crisis,which is an attractive and challenging topic.Hence,various types of photocatalysts have been developed successively to meet the requirements of these photocatalysis.Among them,cobalt‐based heterogeneous catalysts emerge as one of the most promising photocatalysts that open up alluring vistas in the field of solar‐to‐fuels conversion,which can effectively enhance photocatalytic efficiency by extending light absorption range,promoting charge separation,providing active sites,and lowering reaction barrier.In this review,we first present the working principles of cobalt‐based heterogeneous catalysts for photocatalytic water splitting,CO_(2) reduction,and N_(2) fixation.Second,five efficient strategies including surface modification,morphology modulation,crystallinity controlling,crystal engineering and doping,are discussed for improving the photocatalytic performance with different types cobalt‐based catalysts(cobalt nanoparticles and single atom,oxides,sulfides,phosphides,MOFs,COFs,LDHs,carbide,and nitrides).Third,we outline the applications for the state‐of‐the‐art photocatalytic CO_(2) reduction and water splitting,and nitrogen fixation over cobalt‐based heterogeneous catalysts.Finally,the central challenges and possible improvements of cobalt‐based photocatalysis in the future are presented.The purpose of this review is to summarize the past experience and lessons,and provide reference for the further development of cobalt‐based photocatalysis technology.