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转移支付与区域平衡发展

政治经济学评论 2023年第5期14卷 26-59页

作者：樊丽明解垩山东大学经济学院

转移支付与区域平衡发展是宏观经济学领域的重要议题,也是国民收入分配的现实关切。自改革开放以来,中国经济发展取得了巨大成就,但与此同时也引发了区域发展不平衡、收入差距凸显等一系列矛盾,这显然是当前共同富裕目标实现的瓶颈。财... 详细信息

转移支付与区域平衡发展是宏观经济学领域的重要议题,也是国民收入分配的现实关切。自改革开放以来,中国经济发展取得了巨大成就,但与此同时也引发了区域发展不平衡、收入差距凸显等一系列矛盾,这显然是当前共同富裕目标实现的瓶颈。财政转移支付制度作为一种区域补偿政策载体,是实现区域间均衡发展战略的重要手段,更是筑牢边疆安全、维护社会稳定、加强民族团结的有力举措。但在实践中,我国的转移支付制度建设仍存在不足之处,在促进均等化等方面尚未达到令人满意的政策预期,由此备受国内学者的关注。本文通过对相关文献的梳理发现,既有研究搭建了转移支付推动区域平衡发展的基本分析框架,重点聚焦于转移支付对公共服务均等化、地方政府行为以及经济协调发展等方面的影响,并以转移支付的财力均衡效应、地方官员偏好等因素为抓手对内在作用机制做出了进一步的剖析。不可否认的是,我国的转移支付制度在推动区域平衡发展上取得了一定的成效,整体呈现出基本公共服务均等化效应长期趋好的特征,对口支援等具有横向转移支付性质的措施更是充分彰显了中国特色。但是,转移支付在促进区域经济协调发展等方面的功能发挥还有待提升,因此有必要在立足于我国国情和实际的基础上,借鉴国际上的成功经验以健全我国的财政转移支付体系、增强转移支付的精准性和提高资金使用效率。

关键词：转移支付区域平衡发展财力均衡公共服务均等化政府行为

effects of shifting cultivation on biological and biochemical characteristics of soil microorganisms in Khagrachari hill district, Bangladesh

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Journal of Forestry Research 2014年第3期25卷 689-694页

作者： sohag Miah s.M. sirajul Haque Wahida sumi Mohammad Mosharraf Hossain Institute of Forestry and environmental sciences University of Chittagong Department of Microbiology University of Chittagong Department of Applied Physics Graduate School of Engineering Osaka University

We collected soil samples from two representative sites at Aatmile of Khagarachari hill district in Chittagong Hill Tracts. One of the sites was under shifting cultivation and the other an adjacent 13-year old teak plantation. Both sites were in the same physiographic condition and same aspect with parable soil type, which enabled us to measure the effects of shifting cultivation on soil micro-flora. We studied soil phys-ico-chemical properties and the biochemical and biological properties of soil microbes. Moisture and organic matter content as well as fungi and bacterial populations, both in surface and subsurface soils, were signifi-cantly （p≤0.001） lower in shifting cultivated soils compared to soils not under shifting cultivation, i.e. the teak plantation site. The most abundant bacteria in surface （0-10 cm） and sub-surface （10-20 cm） soils under shifting cultivation were Pseudomonas diminuta and shigella, respec-tively, while in corresponding soil layers of teak plantation, predominant microbes were Bacillus firmus （0-10 cm） and Xanthomonas （10-20 cm）. The microbial population differences cannot be explained by soil texture differences because of the textural similarity in soils from the two sites but could be related to the significantly lower moisture and organic mat-ter contents in soils under shifting cultivation.

关键词： shifting cultivation soil biological properties soil biochemical properties soil microflora Chittagong Hill Tracts

Host plant selection of Chrysolina clathrata （Coleoptera： Chrysomelidae） from Mpumalanga, south Africa

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Insect science 2009年第1期16卷 81-88页

作者： Robert s. Boyd Micheal A. Davis Michael A. Wall Kevin Balkwill Department of Biological sciences Auburn University Auburn Alabama Department of Biological sciences University of Southern Mississippi Hattiesburg Mississippi entomology Department San Diego Natural History Museum San Diego California USA C.e. Moss Herbarium School of Animal and Plant Sciences University of the Witwatersrand Private Bag 3 WITS 2050 Johannesburg South Africa

Hyperaccumulated elements such as Ni may defend plants against some natural enemies whereas other enemies may circumvent this defense. The Ni hyperaccumulator Berkheya coddii Roessler （Asteraceae） is a host plant species for Chrysolina clathrata （Clark）, which suffers no apparent harm by consuming its leaf tissue. Beetle specimens collected from B. coddii had a whole body Ni concentration of 260μg/g dry weight, despite consuming leaf material containing 15 100μg Ni/g. Two experiments were conducted with adults of this beetle species： a no-choice experiment and a choice experiment. In the nochoice experiment we offered beetles foliage of one of four speeies ofBerkheya： B. coddii, B. rehmannii Thell. var. rogersiana Thell., B. echinacea （Harv.） O. Hoffm. ex Burtt Davey, and B. insignis （Harv.） Thell. The two former species are Ni hyperaccumulators （defined as having leafNi concentration 〉 1 000 μg/g） whereas the latter have low Ni levels （〈 200 μg/g） in their leaves. Masses of beetles were monitored for 6 days. Choice experiments used growing stem tips from the same Berkheya species, placed into Petri dishes with five Chrysolina beetles in each, and the amount of feeding damage caused on each of the four species was recorded. Beetles in the no-choice experiment gained mass when offered B. coddii, maintained mass on leaves of the other Ni hyperaccumulator （B. rehmannii var. rogersiana）, and lost mass when offered non-hyperaccumulator leaves. In the choice test, beetles strongly preferred B. coddii to other Berkheya species. We conclude that C. clathrata may be host-specific on B. coddii.

关键词： Berkheya coddii bioaccumulation heavy metals host plant specialist nickel

Phenological stage, Plant Biomass, and Drought stress Affect Microbial Biomass and enzyme Activities in the Rhizosphere of enteropogon macrostachyus

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Pedosphere 2019年第2期29卷 259-265页

作者： Kevin Z.MGANGA Bahar s.RAZAVI Muhammad sANAULLAH Yakov KUZYAKOV Department of soil science of Temperate ecosystems Institute of Soil Science University of G?ttingen Department of Range and Wildlife sciences South Eastern Kenya University Department of Agricultural soil science Institute of Soil Science University of G?ttingen Institute of soil and environmental sciences University of AgricultureFaisalabad Institute of environmental sciences Kazan Federal University

Indigenous grasses have been effectively used to rehabilitate degraded African drylands. Despite their success, studies examining their effects on soil bioindicators such as microbial biomass carbon(C) and enzyme activities are scarce. This study elucidates the effects of drought stress and phenological stages of a typical indigenous African grass, enteropogon macrostachyus, on microbial biomass and enzyme activities(β-glucosidase, cellobiohydrolase, and chitinase) in the rhizosphere soil. enteropogon macrostachyus was grown under controlled conditions. Drought stress(partial watering) was simulated during the last 10 d of plant growth, and data were compared with those from optimum moisture conditions. The rhizosphere soil was sampled after 40 d(seedling stage), 70 d(elongation stage), and 80 d(simulated drought stress). A high root:shoot ratio at seedling stage compared with elongation and reproduction stages demonstrated that e. macrostachyus invested more on root biomass in early development, to maximise the uptake of nutrients and water. Microbial biomass and enzyme activities increased with root biomass during plant growth. Ten-day drought at reproduction stage increased the microbial biomass and enzyme activities, accompanying a decrease in binding affinity and catalytic efficiency. In conclusion, drought stress controls soil organic matter decomposition and nutrient mobilization, as well as the competition between plant and microorganisms for nutrient uptake.

关键词： African grass catalytic efficiency cellobiohydrolase chitinase β-glucosidase nutrient uptake optimum moisture soil bioindicators

Translation and Validation of Malay Version 5-Items Brief Illness Perception Questionnaire, BIP-Q5 towards COVID-19 among Malaysian Nurses

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Advances in Infectious Diseases 2022年第3期12卷 383-391页

作者： Hafizah Pasi Nor Azam Kamaruzaman Nadzirah Ahmad Basri Nur Hakimah A. Manan Hashima e. Nasreen Department of Community Medicine Kulliyyah of Medicine International Islamic University Malaysia Kuantan Malaysia Department of Family Medicine Kulliyyah of Medicine International Islamic University Malaysia Kuantan Malaysia Department of Psychiatry Kulliyyah of Medicine International Islamic University Malaysia Kuantan Malaysia Department of Psychiatry and Mental Health Sultan Ahmad Shah Medical Centre (SASMEC) Kuantan Malaysia

Introduction: Currently, own individual perception is recognized as one of the important factors in the prevention of disease, including coronavirus disease, COVID-19. Given the massive impact of COVID-19 on all population’s life, including nurses as one of the main health services providers in the country, this study aims to translate and validate the Malay Version 5-Items Brief Illness Perception Questionnaire, BIP-Q5 towards COVID-19 among Malaysian nurses. Materials and Methods: Forward and backward translations and pretesting of the BIP-Q5 to Malay were conducted among nurses, subject matter experts, and language professionals. The validations process was elicited through an online cross-sectional study involving 56 nurses based on a ~10:1 subject-to-items ratio sample size estimations. Results: The principal component analysis (PCA) revealed one best component with eigenvalues more than one, confirming the questionnaire’s original version. There are five items within the single component, and all are with weightage of over 43%. The scree plot supported the findings, which showed that at least one factors are suitable to be retained. The overall Cronbach’s α coefficient was 0.7 and the intraclass correlation coefficient was 0.659. The Kaiser-Meyer-Olkin was 0.655, and Bartlett’s test of sphericity p-value was Conclusion: This study showed that the translated Malay Version 5-Items Brief Illness Perception Questionnaire, BIP-Q5 has a good psychometric property, and is a valid and reliable tool to be used to measure illness perceptions towards COVID-19 among Malaysian nurses.

关键词： Validation Malay BIP-Q5 COVID-19 Nurses

Facile,Noncovalent Decoration of Graphene Oxide sheets with Nanocrystals

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Nano Research 2009年第3期2卷 192-200页

作者： Ganhua Lu shun Mao sungjin Park Rodney s.Ruoff Junhong Chen Department of Mechanical engineering University of Wisconsin-Milwaukee3200 N.Cramer St.MilwaukeeWI 53211USA Department of Mechanical engineering and the Texas Materials Institute University of Texas at Austin204 E.Dean KeetonAustinTX 78712USA

Facile dry decoration of graphene oxide sheets with aerosol Ag nanocrystals synthesized from an arc plasma source has been demonstrated using an electrostatic force directed assembly technique at room *** Ag nanocrystal-graphene oxide hybrid structure was characterized by transmission electron microscopy(TeM)and selected area *** ripening of Ag nanocrystals on a graphene oxide sheet was studied by consecutive TeM imaging of the same region on a sample after heating in Ar at elevated temperatures of 100°C,200°C,and 300°*** average size of Ag nanocrystals increased and the number density decreased after the annealing *** particular,migration and coalescence of Ag nanocrystals were observed at a temperature as low as 100°C,suggesting a van der Waals interaction between the Ag nanocrystal and the graphene oxide *** availability of affordable graphene-nanocrystal structures and their fundamental properties will open up new opportunities for nanoscience and nanotechnology and accelerate their applications.

关键词： Graphene oxide silver nanocrystals hybrid nanostructures nanocrystal ripening

Identification of dynamic model parameters for lithium-ion batteries used in hybrid electric vehicles

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High Technology Letters 2010年第1期16卷 6-12页

作者：张彩萍 Zhang Chengning Liu Jiazhong sharkh s M National eng/neering Laboratory for electric Vehicle School of Mechanical and Vehicular Engineering Beijing Institute of Technology Beijing 100081 P.R. China school of engineering sciences University of Southampton Highfield Southampton SO17 1BJ UK

An electrical equivalent circuit model for lithium-ion batteries used for hybrid electric vehicles (HeV) is presented. The model has two RC networks characterizing battery activation and concentration polarization process. The parameters of the model are identified using combined experimental and extended Kalman filter (eKF) recursive methods. The open-circuit voltage and ohmic resistance of the battery are directly measured and calculated from experimental measurements, respectively. The rest of the coupled dynamic parameters, i.e. the RC network parameters, are estimated using the eKF method. experimental and simulation results are presented to demonstrate the efficacy of the proposed circuit model and parameter identification techniques for simulating battery dynamics. © by High Technology Letters Press.

关键词：锂离子电池模型参数混合动力电动车用扩展卡尔曼滤波等效电路模型鉴定

Population distribution and threats to sustainable management of selected non-timber forest products in tropical lowland rainforests of south western Nigeria

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Journal of Forestry Research 2013年第1期24卷 75-82页

作者： Jimoh s.O. Amusa T.O. I.O. Azeez Department of Forest Resources Management University of IbadanNigeria. Department of Forest Resources Management University of IlorinNigeria.

Uncontrolled harvesting of non-timber forest products （NTFPs） poses a serious risk of extermination to several of these species in Nigeria. Yet, there is a paucity of information on the distribution, population status and sustainable management of NTFPs in most of the tropical lowland rainforests. We, therefore, assessed the population, distribution and threats to sustainable management of NTFPs within the tropical lowland rainforests of Omo and shasha Forest Reserves, south western Nigeria. Data were obtained through inventory surveys on five top priority species including： bush mango （Irvingia gabonensis （Aubry-Lecomte ex O’Rorke） Baill）, African walnut （Tetracarpidium conophorum （Mull. Arg.） Hutch. ＆ Dalziel syn. Plukenetia conophora）, chew-stick （Massularia acuminata （G. Don） Bullock）, fever bark （Annickia chlorantha setten ＆ *** syn. enantia chloranta） and bush pepper （Piper guineense schumach. ＆ Thonn.）. Purposive and stratified random sampling techniques were used for the inventory. each forest reserve was stratified into three, viz： less disturbed natural forest （for areas that have been rested for at least ten years）, recently disturbed natural forest （for areas that have suffered one form of human perturbation or the other in the last five years）, and plantation forest （for areas carrying forest plantation）. Data were collected from eighteen 10 m × 500 m belt transects located in the above strata. The species were generally fewer in both plantation and recently disturbed natural forest than the less disturbed natural forest, suggesting that forest disturbances （habitat modification） for other uses may have an effect on the occurrence and densities of the NTFPs. exceptions to this trend were found for P. guineense and T. conophorum, which were fairly common in both plantation and recently disturbed natural forest. Among three tree NTFP species （i.e. I. gabonensis, M. acuminata and A. chlorantha）, only I. gabonensis showed a significant difference in ov

关键词： Tropical rainforest non-timber forest products (NTFP) population density distribution forest management

Optimization of Torsional stiffness for Heavy Commercial Vehicle Chassis Frame

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Automotive Innovation 2018年第4期1卷 352-361页

作者： s.H.Gawande A.A.Muley R.N.Yerrawar Department of Mechanical engineering M.E.S.College of Engineering PuneS.P.Pune UniversityPuneIndia

The chassis frame is the backbone of a heavy commercial vehicle(HCV).Its main purpose is to securely carry the determined load under all designed operative ***,it should be rigid enough to withstand the various forces acting on *** objective of this study was to develop a stiffness model to select an optimum cross section with determined torsional ***’s method of optimization was adapted to develop a stiffness equation and select a section with a determined torsional stiffness and a requiredmass *** stiffness obtained from the developed stiffnessmodel and finite element analysis(FeA)is a close match,which proves the validity of the proposed *** section with the maximum torsional stiffness was used for frame-level optimization to improve the torsional and lateral stiffness of the overall chassis *** strain energy absorption capacity of the cross member improved by changing the section of the cross *** using the optimized section,the torsional stiffness of the frame improved by 44%and a lateral stiffness of 10%was *** Creo software was used for modeling and FeA was performed with the Hypermesh software.

关键词： Chassis frame Torsional stiffness FeA Cross members Deformation