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Systematic Review of Community Type 2 Diabetes Structured Health Education (CT2DSHE)
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作者 Gift Phiri 《Open Journal of Nursing》 2024年第8期377-400,共24页
Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming t... Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming to summarize the results of prior primary research studies on available evidence Community type 2 diabetes structured education (CT2DSHE). Methods: Research question: Type 2 diabetic structured health education within a community how effective is it? Qualitative Systematic review, defined as a way to get reliable and objective picture of current available evidence on the specific topic—(CT2DSHE), (Denscombe, 2021) through reflexivity synthesis of available data as an example. This is valuable in time constraints such as project assignments that must be met within specific time and also to bring together available evidence together [1]. Results: This review has shown that CT2DSHE is effective with seven out of the eleven authors supporting, three authors against and one was neutral, further showed that knowledge and skills acquired can last longer with patient activation improved among T2DM patients ideal for sustaining their self-management of T2DM. Conclusion: This research provides suggestive answers to the research question: “Type 2 diabetic structured health education within a community how effective is it?”, This has demonstrated CT2DSHE effectiveness in knowledge acquisition and improving T2DM awareness among T2DM patients, whilst evidencing long effects beyond the study times of 3 - 9 months period in relation to patient activation. Also Identified diabetes education self-management on newly diagnosed (DESMOND) patient as CT2DSHE program for recommendation. Patient or Public Contribution: This work aspires to contribute to CT2DSHE in these areas;Influencing policy decision-making for community diabetes care within the UK and world at large., Contributing to already vast knowledge on diabetes self-management and reasons why?, Influencing educators on how CT2DSHEP are designed, delivered by putting the patient at the Centre and bringing different perspectives on CT2DSHEP in one place that is serving users time of having to consult several resources especially busy clinicians [2] [3]. 展开更多
关键词 Community Health EDUCATION effectIVENESS Impact Structured and Planned type 2 Diabetes (T2DM)
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Nanoindentation Size Effect on Type 316 Stainless Steel 被引量:1
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作者 姚远 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第B10期30-33,共4页
Nanoindentation size effect was investigated under very low loads on type 316 stainless steel. Nanoindentation measurements were carried out on the samples surfaces with a Berkovich pyramidal diamond indenter applying... Nanoindentation size effect was investigated under very low loads on type 316 stainless steel. Nanoindentation measurements were carried out on the samples surfaces with a Berkovich pyramidal diamond indenter applying loads in the range of 25-1000μN. Simultaneously, AFM images of the sample surface were recorded before and after indentation process .For type 316 stainless steel, the indentation size effect was found. The results were discussed in the terms of the model of geometrically necessary dislocations proposed to interpret the indentation size effect.It can be seen that the square of the nanohardness, H 2, vs the inverse of indentation depth, 1/h, is linearly dependent on the indented depth in the range of 25-150nm,which is a good qualitative agreement with the predictions of the model. However, for shallow indents, the slope of the line severely changes.Some possible mechanisms for this change were proposed. 展开更多
关键词 NANOINDENTATION indentation size effect type 316 stainless steel
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Rebound effect and its decomposition-an analysis based on energy types in China 被引量:1
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作者 Yu Liu Meifang Zhou +1 位作者 Shenghao Feng Yi Wang 《Chinese Journal of Population,Resources and Environment》 2016年第4期245-252,共8页
Rebound effect derived from energy efficiency improvement has been widely invested.However,most of studies focus on the rebound effect of the energy composite level and neither distinguish nor compare different energy... Rebound effect derived from energy efficiency improvement has been widely invested.However,most of studies focus on the rebound effect of the energy composite level and neither distinguish nor compare different energy types.We compare the differences in energy saving and energy rebound between primary and secondary energy sources,and further decompose the rebound effect into production rebound part and final demand component.To do so,we add a module for rebound into a comparative state China-CGE model.We design and test two simulation scenarios using the model.In Scenario 1,all production sectors' energy efficiency of using primary energy increases by 5%.In Scenario 2,all production sectors' energy efficiency of using secondary energy increases by 5%.The results show that Scenario 2 leads to more GDP growth and more energy saving.Our scenarios show rebound effects range between 9.6% and 27.9%,and in general are higher when energy efficiency of using primary energy sources is improved.Our decomposition analysis shows that improving energy efficiency in production sectors would stimulates energy use of final demand.Indeed,the consumption side has significant contribution to rebound in secondary energy use,especially in crude oil and gas.This study reveals that improving efficiency of using secondary energy is better than improving that of primary energy,both in terms of economic impact and energy rebound.And complementary policies that prevent energy services prices from falling too much can be adopted to reduce rebound.Controlling residential energy use could also be effective in reducing rebound,this has particular implication to economies in which residential energy consumption are far from saturation. 展开更多
关键词 Rebound effects energy efficiency energy type CGE model
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Types and Correction Methods of Matrix Effect during Zircon LA-ICP-MS U-Pb Dating 被引量:1
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作者 WANG Jiasong PENG Lina +2 位作者 XU Yawen ZHANG Nan LI Guozhan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期2099-2100,共2页
Matrix effect primarily impacts the accuracy and precision of zircon LA-ICP-MS U-Pb data.This paper describes three types of matrix effect in zircon LA-ICPMS U-Pb dating,i.e.,the element matrix effect,high Ddpa or ura... Matrix effect primarily impacts the accuracy and precision of zircon LA-ICP-MS U-Pb data.This paper describes three types of matrix effect in zircon LA-ICPMS U-Pb dating,i.e.,the element matrix effect,high Ddpa or uranium matrix effect and alpha dose matrix effect,and illustrates the correction of these three effects.In addition,we point out the limitation and possible problems of the existing correction methods. 展开更多
关键词 PB types and Correction Methods of Matrix effect during Zircon LA-ICP-MS U-Pb Dating ICP MS
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Noticeable positive Doppler effect on optical bistability in an N-type active Raman gain atomic system 被引量:2
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作者 常增光 钮月萍 +1 位作者 张敬涛 龚尚庆 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期280-284,共5页
We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity. It is shown that the Doppler effect can greatly enhance the dispersion... We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity. It is shown that the Doppler effect can greatly enhance the dispersion and thus create the bistable behaviour or greatly increase the bistable region, which has been known as the positive Doppler effect on optical bistability. In addition, we find that a positive Doppler effect can change optical bistability from the hybrid dispersion-gain type to a dispersive type. 展开更多
关键词 positive Doppler effect optical bistability N-type atomic system active Raman gain
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Mineralogy,M-type tetrad effect and radioactivity of altered granites at the G.Abu Garadi shear zone,central Eastern Desert,Egypt 被引量:3
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作者 El Nahas H.A. El Feky M.G. Mira H. 《Chinese Journal Of Geochemistry》 EI CAS 2011年第2期153-164,共12页
The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as t... The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (M-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization. 展开更多
关键词 M 类型四个效果 改变的花岗石 G。Abu Garadi 砍地区 中央东方沙漠 埃及
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The type, position and age effect on the cutting reproduction of Picea crassifolia and its rooting mechanism in the Qilian Mountains 被引量:6
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作者 Jianjun Kang Wenzhi Zhao +3 位作者 Ming Zhao Guangyu Li Jiqiang Zhang Zhisheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期993-1002,共10页
Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its r... Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types (softwood, hardwood and root), positions (top, upper, middle and bottom) and ages (7, 10, 15, 20, 25 year-old) were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings (0.5-1.0 cm in diameter) from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid (IAA) and total carbon (TC) rather than abscisic acid (ABA) and total nitrogen (TN). The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings (0.5-1.0 cm in diameter) from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia. 展开更多
关键词 Picea crassifolia Kom type Positionand age effect Cutting reproduction Rooting rate HORMONES Organic substances
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Tensile and tear-type fracture toughness of gypsum material:Direct and indirect testing methods 被引量:1
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作者 Daniel Pietras M.R.M.Aliha +1 位作者 Hadi G.Kucheki Tomasz Sadowski 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第7期1777-1796,共20页
In this context,four specimens,i.e.(i)circumferentially notched cylindrical torsion(CNCT),(ii)circum-ferentially notched cylindrical direct tension(CNCDT),(iii)edge notch disc bend(ENDB)and(iv)three-point bend beam(3P... In this context,four specimens,i.e.(i)circumferentially notched cylindrical torsion(CNCT),(ii)circum-ferentially notched cylindrical direct tension(CNCDT),(iii)edge notch disc bend(ENDB)and(iv)three-point bend beam(3PBB),were utilized to measure the modesⅠandⅢfracture toughness values of gypsum.While the CNCT specimen provides pure modeⅢloading in a direct manner,this pure mode condition is indirectly produced by the ENDB specimen.The ENDB specimen provided lower KⅢc and a non-coplanar(i.e.twisted)fracture surface compared with the CNCT specimen,which showed a planar modeⅢfracture surface.The ENDB specimen is also employed for conducting pure modeⅠ(with different crack depths)and mixed modeⅠ/Ⅲtests.KIc value was independent of the notch depth,and it was consistent with the RILEM and ASTM standard methods.But the modeⅢfracture results were highly sensitive to the notch depth.While the fracture resistance against modeⅢwas significantly lower than that of modeⅠ,the greater work of fracture under modeⅢwas noticeable. 展开更多
关键词 GYPSUM Pure modesⅠandⅢfracture toughness Mixed modeⅠ/Ⅲ Circumferentially notched cylindrical torsion(CNCT)specimen Circumferentially notched cylindrical direct tension(CNCDT)specimen Edge notch disc bend(ENDB)specimen Experimental measurement Geometry and loading type effects
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Particle concentration effect in adsorption/desorption of Zn(Ⅱ) on anatase type nano TiO_2 被引量:2
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作者 YANG Yu-huan CHEN Hao PAN Gang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第12期1442-1445,共4页
Adsorption/desorption in a new Zn(Ⅱ)-TiO2 adsorption system was investigated at different particle concentrations (Cp). TEM, SEM and XRD analyses revealed that the TiO2 particles were an aggregation of nano-sized... Adsorption/desorption in a new Zn(Ⅱ)-TiO2 adsorption system was investigated at different particle concentrations (Cp). TEM, SEM and XRD analyses revealed that the TiO2 particles were an aggregation of nano-sized (approximately 10 nm) pure anatase-type TiO2. Adsorption experiments were carried out with particle concentrations of 100, 400 and 1000 mg/L, and their adsorption isotherms were found to decline successively, showing an obvious Cp effect. Desorption experiments indicated that adsorption in this system was irreversible, and the irreversibility increased with increasing Cp. These phenomena could be explained by the MEA (metastable equilibrium adsorption) theory and the Cp effect could be modeled well with an MEA-Freundlich-type Cp effect isotherm equation. This study may heln understand environmental behavior of contaminants on ultrafine natural particles. 展开更多
关键词 Zn(Ⅱ) anatase-type Ti02 particle concentrations effect adsorption DESORPTION
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Review of magnetocaloric effect in perovskite-type oxides 被引量:1
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作者 钟伟 区泽棠 都有为 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期24-34,共11页
We survey the magnetocaloric effect in perovskite-type oxides (including doped ABO3-type manganese oxides, A3B2OT-type two-layered perovskite oxides, and A2B'B''O6-type ordered double-perovskite oxides). Magnetic... We survey the magnetocaloric effect in perovskite-type oxides (including doped ABO3-type manganese oxides, A3B2OT-type two-layered perovskite oxides, and A2B'B''O6-type ordered double-perovskite oxides). Magnetic entropy changes larger than those of gadolinium can be observed in polycrystalline La1-xCaxMnO3 and alkali-metal (Na or K) doped La0.8Ca0.2MnO3 perovskite-type manganese oxides. The large magnetic entropy change produced by an abrupt reduction of magnetization is attributed to the anomalous thermal expansion at the Curie temperature. Considerable mag- netic entropy changes can also be observed in two-layered perovskites Lal.6Cal.4Mn207 and La2.5-xK0.5+xMn2O7+6 (0 〈 x 〈 0.5), and double-perovskite Ba2Fe1+xMol-xO6 (0 〈 x 〈 0.3) near their respective Curie temperatures. Com- pared with rare earth metals and their alloys, the perovskite-type oxides are lower in cost, and they exhibit higher chemical stability and higher electrical resistivity, which together favor lower eddy-current heating. They are potential magnetic refrigerants at high temperatures, especially near room temperature. 展开更多
关键词 perovskite-type oxides magnetocaloric effect magnetic entropy change magnetic phase transi-tion
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Effects of gate-buffer combined with a p-type spacer structure on silicon carbide metal semiconductor field-effect transistors
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作者 Song Kun Chai Chang-Chun +3 位作者 Yang Yin-Tang Chen Bin Zhang Xian-Jun Ma Zhen-Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期426-432,共7页
An improved structure of silicon carbide metal-semiconductor field-effect transistors (MESFET) is proposed for high power microwave applications. Numerical models for the physical and electrical mechanisms of the de... An improved structure of silicon carbide metal-semiconductor field-effect transistors (MESFET) is proposed for high power microwave applications. Numerical models for the physical and electrical mechanisms of the device are presented, and the static and dynamic electrical performances are analysed. By comparison with the conventional structure, the proposed structure exhibits a superior frequency response while possessing better DC characteristics. A p-type spacer layer, inserted between the oxide and the channel, is shown to suppress the surface trap effect and improve the distribution of the electric field at the gate edge. Meanwhile, a lightly doped n-type buffer layer under the gate reduces depletion in the channel, resulting in an increase in the output current and a reduction in the gate-capacitance. The structural parameter dependences of the device performance are discussed, and an optimized design is obtained. The results show that the maximum saturation current density of 325 mA/mm is yielded, compared with 182 mA/mm for conventional MESFETs under the condition that the breakdown voltage of the proposed MESFET is larger than that of the conventional MESFET, leading to an increase of 79% in the output power density. In addition, improvements of 27% cut-off frequency and 28% maximum oscillation frequency are achieved compared with a conventional MESFET, respectively. 展开更多
关键词 silicon carbide metal-semiconductor field-effect transistor p-type spacer gate-buffer
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Molecular Cloning and Bioinformatics Analysis of TypeⅢSecretion System Effector Protein Va1686 Gene of Vibrio alginolyticus 被引量:2
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作者 Zhihao WU Mingjie FAN +6 位作者 Jiaming LIAO Huanying PANG Chuanhao PAN Dawei SONG Mingsheng QIU Shuanghu CAI Jichang JIAN 《Agricultural Biotechnology》 CAS 2018年第5期8-12,15,共6页
In this study, Va 1686 gene was cloned from Vibrio alginolyticus . The total length of the gene is 1 164 bp, and it could encode 387 amino acids. The physicochemical properties, protein structure, genetic evolutionary... In this study, Va 1686 gene was cloned from Vibrio alginolyticus . The total length of the gene is 1 164 bp, and it could encode 387 amino acids. The physicochemical properties, protein structure, genetic evolutionary relationship and antigenic characteristics of the effect protein Va1686 of V. alginolyticus HY9901 type Ⅲ secretion system were studied and analyzed by bioinformatics methods and tools. The results showed that Va1686 is a stable hydrophilic and acidic protein without a transmembrane region and a signal peptide, and secondary structure to α-helix. The evolutionary analysis showed that V. alginolyticus HY9901 and V. harveyi were clustered together, which indicated that the genetic relationship between the two species was the closest. Va1686 contains a Fic superfamily conserved domain associated with cell division. Bioinformatics analysis showed that the B-cell preponderant epitopes of Va1686 might be localized in the regions of 48-49, 82-85, 125-126, 150-153, 185-186, 236-237 and so on. The 3D structure model of Va1686 subunit was simulated by SWISS-MODEL software and it was found that the vopS of V. parahaemolyticus was similar and the similarity was 89.46%. In this study, the feasibility of Va1686 as a common antigen of Vibrio was verified from the perspective of bioinformatics, which laid the foundation for the next step in vaccine development. 展开更多
关键词 Vibrio alginolyticus type secretory system effect protein Bioinformatics analysis
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Effect of Botubinum toxin type A injection into the masseter muscle on mandibular development in rats
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作者 黄进军 《外科研究与新技术》 2011年第2期132-132,共1页
Objective To investigate the effect of Botulinum toxin type A(Botox)injection into the masseter muscle on mandibular development in rats.Methods 1228-day-old Wistar rats were divided into two groups as Botox group(n=6... Objective To investigate the effect of Botulinum toxin type A(Botox)injection into the masseter muscle on mandibular development in rats.Methods 1228-day-old Wistar rats were divided into two groups as Botox group(n=6)and control group(n=6) 展开更多
关键词 effect of Botubinum toxin type A injection into the masseter muscle on mandibular development in rats type
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The Dynamical Behavior of a Predator-Prey System with Holling Type II Functional Response and Allee Effect 被引量:4
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作者 Shuangte Wang Hengguo Yu +1 位作者 Chuanjun Dai Min Zhao 《Applied Mathematics》 2020年第5期407-425,共19页
In this paper, we mainly considered the dynamical behavior of a predator-prey system with Holling type II functional response and Allee-like effect on predator, including stability analysis of equilibria and Hopf bifu... In this paper, we mainly considered the dynamical behavior of a predator-prey system with Holling type II functional response and Allee-like effect on predator, including stability analysis of equilibria and Hopf bifurcation. Firstly, we gave some sufficient conditions to guarantee the existence, the local and global stability of equilibria as well as non-existence of limit cycles. By using the cobweb model, some cases about the existence of interior equilibrium are also illustrated with numerical outcomes. These existence and stability conclusions of interior equilibrium are also suitable in corresponding homogeneous reaction-diffusion system subject to the Neumann boundary conditions. Secondly, we theoretically deduced that our system has saddle-node bifurcation, transcritical bifurcation and Hopf bifurcation under certain conditions. Finally, for the Hopf bifurcation, we choose d as the bifurcation parameter and presented some numerical simulations to verify feasibility and effectiveness of the theoretical derivation corresponding to the existence of yk, respectively. The Hopf bifurcations are supercritical and limit cycles generated by the critical points are stable. 展开更多
关键词 PREDATOR-PREY System HOLLING type II FUNCTIONAL Response Allee effect Stability HOPF BIFURCATION
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土壤中微塑料:类型、载体效应、迁移行为和潜在风险综述 被引量:2
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作者 刘加强 崔陆 +4 位作者 周子振 丁千 杨杨阳 蒋园园 徐蕾 《生态学报》 CAS CSCD 北大核心 2024年第9期3586-3599,共14页
微塑料(microplastics,MPs)作为一种新兴污染物,广泛存在于土壤中,并不断迁移转化,对土壤生态系统和生物多样性产生潜在风险。为了全面评估土壤MPs的环境风险,加强MPs污染的风险管控,讨论了土壤环境中MPs的类型,系统阐述了土壤MPs的载... 微塑料(microplastics,MPs)作为一种新兴污染物,广泛存在于土壤中,并不断迁移转化,对土壤生态系统和生物多样性产生潜在风险。为了全面评估土壤MPs的环境风险,加强MPs污染的风险管控,讨论了土壤环境中MPs的类型,系统阐述了土壤MPs的载体效应和迁移行为,并从微生物、植物、动物以及人类四个方面综述了土壤MPs的潜在风险。土壤中MPs并不是单独存在的,MPs的潜在风险一方面来自其本身(颗粒和添加剂)的生物毒性,另一方面是其对共存污染物(有机污染物、重金属和致病菌等)的载体效应。在非生物(淋溶、重力)和生物等作用下,土壤中的MPs时刻都在经历着复杂的迁移过程,从而加剧了其对土壤生态系统的影响。由于粒径小,MPs很容易进入食物链并层层传递,从而对不同营养级生物的正常生理活动产生不利影响,包括影响土壤动植物的新陈代谢,生长,发育和繁殖。此外,MPs不仅在环境中存在,而且也在人体中被发现。MPs可通过饮食、呼吸或皮肤接触等途径进入人体,从而对人体可能产生一系列不良反应。虽然目前仍没有足够的证据证明MPs对人体的直接危害,但其潜在风险仍不容忽视。探讨了土壤MPs污染治理的策略,并对未来土壤微塑料污染的研究方向和重点进行了展望。研究将有助于加深人们对土壤微塑料污染的认识,并为更好地开展微塑料的毒理效应研究和风险评估提供科学线索和理论参考。 展开更多
关键词 土壤微塑料 类型 载体效应 迁移行为 毒性效应 治理策略
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秦巴山区生态系统服务对植被覆盖变化的响应阈值
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作者 王晓峰 白娟 +6 位作者 冯晓明 周继涛 王筱雪 尧文洁 涂又 孙泽冲 马嘉豪 《生态学报》 CAS CSCD 北大核心 2024年第15期6811-6827,共17页
秦巴山区地处我国南北气候、生物区系的交汇地带,具有十分重要的地理与生态价值,蕴藏着巨大的发展潜力。确定生态系统服务对植被覆盖变化的响应阈值是实现秦巴山区环境资源有效配置、管理政策科学制定以及生态效益最大化的重要前提。在... 秦巴山区地处我国南北气候、生物区系的交汇地带,具有十分重要的地理与生态价值,蕴藏着巨大的发展潜力。确定生态系统服务对植被覆盖变化的响应阈值是实现秦巴山区环境资源有效配置、管理政策科学制定以及生态效益最大化的重要前提。在分析秦巴山区产水、固碳、土壤保持和生境质量4项生态系统服务时空特征的基础上,综合运用聚类分析、方差分析和弹性分析对比不同植被类型和地形梯度下生态系统服务的异同进而分区计算植被覆盖变化的影响阈值。结果表明:(1)2000—2020年,产水、固碳、土壤保持和生境质量服务整体提升且均表现为东南高西北低的空间分布。(2)不同类型植被下,生态系统服务整体供应能力从大到小依次为林地、草地和农田。不同地形变化下,除生境质量呈持续增长态势外,其他3项服务均出现了先提高后衰减的非线性趋势。(3)植被覆盖度对生态系统服务有促进作用,但超过一定阈值后这种作用会逐渐减弱。植被覆盖影响阈值在林地、草地和农田区分别为0.85、0.80和0.78;且该阈值随地形因子增加先增大后减小。本研究结果可以转变秦巴山区单纯依靠扩大森林面积提升生态系统服务供给的简单化生态保护模式,为构建分区管理、全面系统和动态平衡的生态可持续发展体系提供依据。 展开更多
关键词 生态系统服务 植被覆盖变化 阈值 植被类型 地形梯度
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Effects of a Community-Based Intervention on the Lifestyle and Health of People at Risk of Type 2 Diabetes in Benin
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作者 Clemence Germaine Metonnou Colette Sylvie Azandjeme +3 位作者 Charles Jerome Sossa Bio Nigan Issiako Moussiliou Noël Paraïso Victoire Agueh 《Food and Nutrition Sciences》 CAS 2022年第10期842-860,共19页
Introduction: Worldwide, the prevalence of type 2 diabetes (T2D) is increasing at an epidemic rate. The objective of this study was to measure the effects on lifestyle intervention in subjects at risk of T2D in a West... Introduction: Worldwide, the prevalence of type 2 diabetes (T2D) is increasing at an epidemic rate. The objective of this study was to measure the effects on lifestyle intervention in subjects at risk of T2D in a West African country. Methods: This study involved Beninese adults at risk of T2D randomly selected from 2 groups of villages: control villages and villages exposed to nutrition education, cooking demonstrations and physical activity sessions. Anthropometric, clinical, and biological measurements were taken in both groups at the beginning and end of the intervention, which lasted 12 months. The paired sample t-test was used to assess the effect of the intervention on the lifestyle of people at risk of T2D. Results: After 12 months of exposure to nutrition education, cooking demonstrations and physical activity sessions in the intervention villages, the mean body mass index, waist circumference, body fat percentage, blood glucose, triglycerides, total cholesterol and amount of alcohol consumed per week had significantly decreased. Conversely, the mean intensity of physical activity and food consumption score had significantly increased. In the control group, 5.6% of the people at risk developed to diabetes. The relative risk was RR = 0.20 [0.14 - 0.56]. Conclusion: The intervention significantly improved metabolic indicators, intensity of leisure activity and dietary score. We suggest larger studies to better assess the effect of community-based interventions on the lifestyle and health of people at risk of T2D in Africa. 展开更多
关键词 effectS Primary Prevention People at Risk of type 2 Diabetes BENIN
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投资者意见分歧与企业创新
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作者 张静 杨娅萍 《经济与管理》 北大核心 2024年第1期82-92,共11页
基于企业财务决策与资本市场之间的联动性关系,研究投资者意见分歧对企业创新的影响,以及包含传统新闻媒体和网络新闻媒体在内的多源媒体对企业的报道态度异质性对二者关系的影响。结果表明,投资者意见分歧通过管理层情绪效应抑制了企... 基于企业财务决策与资本市场之间的联动性关系,研究投资者意见分歧对企业创新的影响,以及包含传统新闻媒体和网络新闻媒体在内的多源媒体对企业的报道态度异质性对二者关系的影响。结果表明,投资者意见分歧通过管理层情绪效应抑制了企业创新。相比传统新闻媒体,网络新闻媒体报道态度异质性更能强化投资者意见分歧对企业创新的抑制作用。进一步研究发现,投资者意见分歧激发管理层悲观情绪效应,并受到股权分散程度的正向影响和高管异质性的负向影响。投资者意见分歧通过管理层情绪效应对探索式创新影响更大,最终降低企业价值。 展开更多
关键词 投资者意见分歧 企业创新 管理层情绪效应 创新类型
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绿色信贷政策与污染型僵尸企业治理:淘汰与转型的双重效应 被引量:2
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作者 南晓莉 岳俐 《大连理工大学学报(社会科学版)》 北大核心 2024年第1期23-32,共10页
以2007年绿色信贷政策出台为事件构造了准自然实验,基于中国工业企业数据库,采用双重差分法考察了绿色信贷政策对污染型僵尸企业的淘汰效应与转型效应及其影响机制。实证结果发现,政策显著增加了污染型僵尸企业的退出概率,且对于存续的... 以2007年绿色信贷政策出台为事件构造了准自然实验,基于中国工业企业数据库,采用双重差分法考察了绿色信贷政策对污染型僵尸企业的淘汰效应与转型效应及其影响机制。实证结果发现,政策显著增加了污染型僵尸企业的退出概率,且对于存续的污染型僵尸企业生产率提升具有显著的促进作用。绿色信贷政策淘汰效应的作用机制,来自融资可得性降低和融资成本增加导致的银行信贷资源配置合理化的影响;绿色信贷政策转型效应的作用机制,来自政策强化外部监督引致的代理成本下降。异质性分析发现,绿色信贷政策的淘汰效应和转型效应在环境规制强度较高、市场化水平较高的地区以及劳动力密集较低行业更显著,且淘汰效应在非国有企业更显著,转型效应在国有企业更显著。将绿色信贷政策与解决僵尸企业难题的有效结合,加快转变经济发展方式,对如何缓解信贷资源错配,加快推进僵尸企业治理提出相应的政策建议。 展开更多
关键词 绿色信贷政策 僵尸企业 污染型 淘汰效应 转型效应
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A Review of Geothermal Type-Curves with Damage Effect: A Case of Practical Apply to a Mexican Geothermal Field
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作者 Siomara López-Blanco Alfonso Aragón-Aguilar +3 位作者 Víctor Arellano-Gómez Georgina Izquierdo-Montalvo Sócrates Santoyo-Gutiérrez Abel Hernández-Ochoa 《International Journal of Geosciences》 2012年第3期591-600,共10页
A review of the art state was developed about the inflow relationships and their application for reservoir characterization. The theoretical development of the methodology for determining the damage effect using type-... A review of the art state was developed about the inflow relationships and their application for reservoir characterization. The theoretical development of the methodology for determining the damage effect using type-curves of the inflow relationships was shown. We show the process followed for achieve the geothermal type-curve affected with damage for reservoirs with mean salinities of 30000 ppm and temperatures up to 350℃. This type-curve was applied using measurement production data in a Mexican geothermal field. According with the obtained results is shown that the methodology for determining the damage effect using production measurements is a sure alternative for the damage effect calculation. It was used an alternative methodology in order to validate the damage presence and the obtained results were consistent. Last thing shows that both methodologies can be combined as a confident manner. 展开更多
关键词 GEOTHERMAL Reservoir INFLOW Performance RELATIONSHIPS type-Curves Damage effect Well Production Mass Flow Rate Output CURVES
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