如何让学生的数学学习能力活起来

数学是一门需要学生凸显学习能力的课程,数学课程又是相当抽象的课程。小学生进行数学学习,多具有数学抽象与思维必须形象之间的矛盾。数学教学需要在让学生的数学学习能力活起来上下功夫。笔者对如何让学生的数学学习能力活起来做了一系列研究。

围手术期应用谷氨酰胺双肽对血内毒素水平、血浆灭活内毒素能力及预后的影响(随机、双盲、对照的临床研究)

目的研究围手术期应用谷氨酰胺双肽对血浆内毒素水平、血浆灭活内毒素能力及预后的影响。方法采用前瞻、随机、双盲和对照的研究设计,28例患者参加研究。研究组和对照组所接受的氮量和热卡相同;研究组在术前1天到术后3天接受谷氨酰胺双肽0.5g·kg-1·d-1(20%Dipetiven,FreseniusKabi),对照组接受相同氮量的平衡氨基酸。患者分别于手术前1天,术后3和24小时,4天和第7天取外周血。测定血浆内毒素水平和血浆灭活内毒素能力。监测与感染有关的并发症、肠外营养用药费用、总住院费用和术后住院日。结果28例患者均完成研究。数据输入电脑,核对无误后开盲,进入对照组14例,研究组14例。两组术前术后各时间点血浆内毒素水平差值间无显著性差别(P=0.08～0.91);而血浆灭活内毒素能力在术后3d研究组较对照组增强犤差值分别为(+0.157±0.020)EU/ml和(+0.109±0.004)EU/ml,P=0.01犦。对照组出现2例与感染有关的并发症,研究组未出现,组间无显著性差异(P=0.31)。研究组肠外营养用药费用(4302±749)元较对照组(3322±806)元高出(980±772)元,组间无显著性差别(P=0.12);总住院费用研究组为(24816±7291)元较对照组(26194±6372)元低(1368±1081)元,组间无显著性差别(P=0.39);研究组术后住院日数(10.7±1.5)天较对照组(12.1?

远程教育应把培养学生“活的能力”放在重要位置——从开放教育毕业生追踪调查探讨成人学生的能力培养

通过对开放教育毕业生的系统、规范的调查,发现毕业生在解决实际问题,尤其是创新能力素质等方面普遍存在着欠缺。应把培养学生“活的能力”作为开放素质教育的核心的观点,分析了“活的能力”的特征并具体阐述了教育教学中如何培养“活的能力”的着力点和实施策略等进行了思考。

首届兽药职业技能大赛参赛选手活菌计数能力分析

通过对首届兽药职业技能大赛62名参赛选手大肠杆菌活菌计数结果进行分析,了解我国兽用生物制品生产企业活菌计数能力的整体水平。每名参赛选手发放大肠杆菌菌液1支,要求参赛选手在规定时间内进行活菌计数并提交计数结果。40%参赛选手活菌计数检验结果满意(25/62);60%检验结果不满意(37/62)。此次技能大赛体现出我国兽用生物制品生产企业检验人员的活菌计数水平参差不齐,部分检验人员活菌计数能力有待进一步提高。

“重建生活为本”作业治疗病房延伸训练对脑卒中偏瘫患者上肢功能及日常生活活动能力的影响

目的研究并探讨"重建生活为本"作业治疗病房延伸训练对脑卒中(CVA)偏瘫患者上肢功能及日常生活活动能力的影响。方法 60例CVA偏瘫患者,在计算机中采取随机数字表法分为对照组和观察组,每组30例。对照组采用常规综合康复疗法,观察组在对照组基础上进行"重建生活为本"作业治疗病房延伸训练。比较两组患者治疗前、治疗4周后上肢功能、日常生活活动能力。结果治疗前,两组患者Fugl-Meyer量表(FMA)评分、改良Barthel指数量表(MBI)评分比较差异无统计学意义(P>0.05);治疗4周后,两组患者FMA评分、MBI评分均较本组治疗前升高,且观察组患者FMA评分(43.23±3.92)分、MBI评分(80.68±6.21)分均高于对照组的(30.16±4.32)、(60.98±6.81)分,差异具有统计学意义(P<0.05)。结论 "重建生活为本"作业治疗病房延伸训练有利于增强CVA偏瘫患者的肢体运动功能,促使其日常生活能力大大提升,建议临床推广应用。

车前草根际土壤细菌的筛选鉴定与功能初探

从车前草(Plantago asiatica L.)根际土壤中筛选发现潜在的具有活硒能力、抑镉能力或二者能力兼之的细菌菌株。首先,采用稀释涂布平板法从车前草根际土壤中分离纯化出耐硒耐镉细菌;将分离得到的耐硒耐镉细菌进行16S r RNA基因鉴定;然后,利用土壤固体培养基对细菌进行培养,并用氢化物发生原子荧光光谱法和电感耦合等离子体发射光谱法分别测定不同细菌对应土壤的有效硒和有效镉,计算出菌株活硒率和抑镉率;最后,初步评价菌株对土壤硒或镉活化或抑制的能力。试验结果从车前草根际土壤中分离鉴定二级细菌8株,其中活硒率超过100%的菌株有CQC-3、CQC-8、CQC-11、CQC-12,抑镉率超过20%的菌株有CQC-7、CQC-8、CQC-12、CQC-13,活硒抑镉能力兼具的菌株有CQC-8和CQC-12,此研究结果为后续解决土壤和植物硒镉伴生问题、活硒抑镉机理研究和菌剂的开发提供基础资料。

Non-isothermal thermal decomposition kinetics of high iron gibbsite ore based on Popescu method

The thermal decomposition kinetics of high iron gibbsite ore was investigated under non-isothermal conditions.Popescu method was applied to analyzing the thermal decomposition mechanism.The results show that the most probable thermal decomposition mechanism is the three-dimensional diffusion model of Jander equation,and the mechanism code is D3.The activation energy and pre-exponential factor for thermal decomposition of high iron gibbsite ore calculated by the Popescu method are 75.36 kJ/mol and 1.51×10-5 s-（-1）,respectively.The correctness of the obtained mechanism function is validated by the activation energy acquired by the iso-conversional method.Popescu method is a rational and reliable method for the analysis of the thermal decomposition mechanism of high iron gibbsite ore.

Kinetics analysis of decomposition of vanadium slag by KOH sub-molten salt method

A novel process was developed for the decomposition of vanadium slag using KOH sub-molten salt under ambient pressure, and the effects of reaction temperature, alkali-to-ore mass ratios, particle size, and stirring speed on vanadium and chromium extraction were studied. The results suggest that the reaction temperature and KOH-to-ore mass ratio are more influential factors for the extraction of vanadium and chromium. Under the optimal reaction conditions （temperature 180 °C, initial KOH-to-ore mass ratio 4：1, stirring speed 700 r/min, gas flow 1 L/min, and reaction time 300 min）, vanadium and chromium extraction rates can reach up to 95% and 90%, respectively. Kinetics analysis results show that the decomposing process of vanadium slag in KOH sub-molten salt can be well interpreted by the shrinking core model under internal diffusion control. The apparent activation energies for vanadium and chromium are 40.54 and 50.27 kJ/mol, respectively.

Effects of Sunflower Artificial Aging on Seed Vigor and Physiological Characteristics

[Objective]The aim was to study the effects of sunflower artificial aging on seed vigor and physiological characteristics.[Method] The varieties of seed germination capacity,vigor of germination,germination index,vigor index,peroxidase（POD） activity,superoxide dismutase（SOD） activity and malondialdehyde（MDA） content for four sunflower germplasms such as＇SunM20＇,＇Deep Purple Minle＇,＇Da San Kui Hua 4＇and＇Ji Kui 24＇were studied under high temperature and high humidity conditions（100% RH,45 ℃） for different days（0 d,2 d,4 d,6 d,8 d,10 d）.[Result]The result showed that the germination capacity,vigor of germination,germination index,vigor index,POD activity,SOD activity declined gradually with the increase of seed aging days,whereas MDA content enhanced by degrees;The diggerences of resistance to artifical aging existed among the four accessions,＇SunM20＇was the most resistant one,and exhibited the strongest seed vigor,highest activities of two protective enzyme（POD,SOD） and lowest content of MDA at the uniform condition,moreover,the seed vigor and protective enzyme activities of＇SunM20＇changed slowest among the four materials during the aging process.[Conclusion]The distinct reduction of POD,SOD activities maybe the main reasons for the decrease of sunflower seed vigor at the artificial aging,and the gradual accumulation of a few MDA accelerated seeds aging.

Effect of Si on growth kinetics of intermetallic compounds during reaction between solid iron and molten aluminum

The effect of Si on the growth kinetics of intermetallic compounds during the reaction of solid iron and molten aluminum was investigated with a scanning electron microscope coupled with an energy dispersive X-ray spectroscope, and hot-dip aluminized experiments. The results show that the intermetallic layer is composed of major Fe2Al5 and minor FeAl3. The Al-Fe-Si ternary phase, rl/rg, is formed in the Fe2Al5 layer. The tongue-like morphology of the Fe2Als layer becomes less distinct and disappears finally as the content of Si in aluminum bath increases. Si in the bath improves the prohibiting ability to the growth of Fe2Als and FeAl3. When the contents of Si are 0, 0.5%, 1.0%, 1.5%, 2.0% and 3.0%, the activation energies of Fe2Al5 are evaluated to be 207, 186, 169, 168, 167 and 172 kJ/mol, respectively. The reduction of the activation energy might result from the lattice distortion caused by Si atom penetrating into the Fe2Al5 phase. When Si atom occupies the vacancy site, it blocks easy diffusion path and results in the disappearance of tongue-like morphology.

Leaching kinetics of gold bearing pyrite in H_2SO_4-Fe_2(SO_4)_3 system

Gold bearing pyrite leaching was conducted in H2SO4-Fe2（SO4）3 system at different reaction temperatures,with different ferric ion concentrations,sulfuric acid concentrations and stirring speeds.The leaching kinetics and mechanism were studied.When the temperature ranged between 30-75 °C,the pyrite leaching was mainly controlled by chemical reaction with positive correlation to the ferric ion concentration.The activation energy obtained from Arrhenius empirical formula is 51.39 k J/mol.The EDS and XPS analyses suggest that the oxidation of sulfur within pyrite is through a series of intermediate stages,and eventually is oxidized to sulphate accompanied with the formation of element sulfur.This indicates a thiosulfate oxidation pathway of the gold bearing pyrite oxidation in H2SO4-Fe2（SO4）3 system.

Multi-dimensional frailty and its risk factors among older residents in long-term care facilities in Shanghai,China

Objectives:The integrated model of frailty shifted the physiologically-dominated view to an integrated and multidisciplinary view of frailty and adopted an integrated and holistic approach to the complex challenges facing frail older adults and their caregivers.There is an urgent need for researchers to identify multi-faceted frailty among older adults and to explore contributors to it.We assessed the level of frailty among older residents in long-term care(LTC)facilities in Shanghai,China and explored risk factors of multiple dimensions of frailty among older residents.Methods:It is a cross-sectional descriptive study.We interviewed 218 older residents from nine LTC facilities.We used Tilburg Frailty Indicator to assess older residents’physiological,psychological,and social frailty.The Geriatric Depression Scale,Mini-Mental state examination,Athens Insomnia Scale,and Activity of Daily Living(ADL)Scale were used to assess their depressive symptoms,cognitive function,sleep quality and ADL abilities,respectively.Results:Older residents have a moderate level of frailty in physiological,psychological and social domains.There is a high correlation among dimensions of frailty.Older residents’depressive symptoms have remained positively associated with their overall and each domain of frailty.Older residents’actual activity participation and exercise in LTC facilities are negatively associated with older residents’overall,physiological and social frailty.Conclusions:Frailty is a multi-dimensional concept and is prevalent among older residents in LTC facilities.It is important to take an integrated view on frailty and carry out appropriate and comprehensive interventions to prevent adverse outcomes and provide holistic care for frail older residents in LTC facilities.There is an urgent need to improve the quality and expand the number of activities offered within LTC facilities that would engage older residents in a person-centered way,despite their age,ADL abilities,frailty and functional limitations.

大数据在商业银行零售业务客户经营管理中的运用

利用大数据已经上升为国家战略。商业银行零售业务是服务社会经济发展和民生改善的基础性业务,提升大数据应用能力,对于商业银行落实普惠金融,解决客户需求,提升客户服务能力,提高客户经营管理效能具有重要作用。但当前商业银行在大数据运用时,面临着亟待解决的问题,如传统客户待客上门的营销模式难于为继,单一产品和服务难于满足多样化的客户需求等,因此,商业银行亟需利用大数据转变客户经营管理模式,提升客户营销服务效能。

Recovery of valuable metals from lepidolite by atmosphere leaching and kinetics on dissolution of lithium

The lepidolite located in Yichun, Jiangxi Province, China, was adopted to investigate the recovery of alkali metals and leaching kinetics of lithium with sulphuric acid solution under atmospheric pressure. The results show that the recoveries of alkali metals were achieved under the leaching conditions: mass ratio of lepidolite with particle size less than 180 μm to sulphuric acid 1.2, leaching temperature 411 K, liquid-solid ratio 2.5∶1, and leaching time 10 h. Under the selected conditions for leaching experiment, the leaching rates of lithium, potassium, rubidium and caesium are 94.18%, 93.70%, 91.81% and 89.22%, respectively. The X-ray diffraction analysis for leaching residue indicates that no insoluble product forms during leaching. The chemical compositions of leaching residue reveal that trace iron, manganese and calcium disappear after acid leaching. The kinetics of leaching process for lithium follows shrinking core model of mixed control and the apparent activation energy is 17.21 kJ/mol. The reaction orders with respect to sulphuric acid concentration and liquid-solid ratio are determined to be 2.85 and 1.66, respectively. A semi-empirical rate equation was obtained to describe the leaching process. The kinetic analysis shows that the leaching process is controlled by diffusion through the insoluble layer of the associated minerals.

Temperature Effect on Boron Adsorption-Desorption Kinetics in Soils

The effect of temperature on the properties of boron adsorption-desorption in brown-red soil, yellowbrown soil and calcareous alluvial soil of Hubei Province was investigated with the mobile displacement technique. The experimental data of B adsorption-desorption amounts and reaction t line at 25 and 40℃ were fitted by the zero-order, first-order and parabolic diffusion kinetic equations. The adsorption process was in conformity with the parabolic diffusion law at both the temperatures, and the values of rate constant of the parabolic diffusion equation in B adsorption were 0.138, 0.124 and 0.105 mg kg-1 min-1/2 at 25℃, and 0.147, 0.146 and 0.135 mg kg-1 min-1/2 at 40℃ for the brown-red soil, yellow-brown soil, and calcareous alluvial soil, respectively. The relationship between amount of B desorption and reaction time could be well described by the first-order kinetic equation, and the corresponding values of rate constant were 0.0422, 0.0563 and 0.0384 min-1 at 25℃, and 0.0408, 0.042 3 and 0.0401 min-1 at 40℃ for the brown-red soil, the yellow-brown soil and the calcareous alluvial soil, respectively. Therefore, the desorption process of B might be related to the amount of B adsorbed in soil. The higher the temperature, the lower the amount of B adsorption for the same soil in the same reaction time. The values of the apparent activation energy of B adsorption in the three soils calculated with the rate constants of parabolic diffusion equation were 3.27, 8.44 and 12.99 kJ mol-1, respectively, based on the experimental data of B adsorption amounts and reaction time at 25 and 40℃.

Effect of Combined Heavy Metal Pollution on Nitrogen Mineralization Potential,Urease and Phosphatase Activities in a Typic Udic Ferrisol

Individual and combined effects of Cu, Pb, Zn and Cd on N mineralization, urease and phosphatase were examined in a Typic Udic Ferrisol in laboratory by employing an uniform design and a single factor design.Soil pollution caused by heavy metals inhibited N mineralization (No value) and urease and phosphatase activities. The combined pollution of metals alleviated their toxicity to N mineralization to some extent,whereas aggravated the toxicity to urease and phosphatase. Phosphorous application could mitigate the toxic effect of heavy metals on phosphatase activities, while alleviating effect of N application on the toxicity of heavy metals to urease was inconsistent. However, the mitigating effect of the fertilizers was limited in heavily polluted soils.

Synthesis of activated carbon from spent tea leaves for aspirin removal

Adsorption capacity of activated carbon prepared from spent tea leaves （STL-AC） for the removal of aspirin from aqueous solution was investigated in this study. Preliminary studies have shown that treatment with phosphoric acid （H3PO4） increased removal efficiency of STL-AC. Characterizations on STL-AC revealed excellent textural properties （1200 m2.g-1, 51% mesoporosity）, as well as distinctive surface chemistry （1.08 mmol.g-1 and 0.54 mmol.g-1 for acidic and basic oxygenated groups, pHpzc = 2.02）. Maximum removal efficiency of aspirin observed was 94.28% after 60 rain when the initial concentration was 100 mg.L-1, 0.5 g of adsorbent used, pH 3 and at a temperature of 30 ℃. The adsorption data were well fitted to the Freundlich isotherm model and obeyed the pseudo-second order kinetics model. The adsorption of aspirin onto STL-AC was exothermic in nature （△H = - 13.808 kJ.mol-1） and had a negative entropy change, △S （-41.444 J.mol-1）. A negative Gibbs free energy, △G was obtained indicating feasibility and spontaneity of the adsorption process. The adsorp- tion capacity of △C-STL （178.57 mg.g-1） is considerably high compared to most adsorbents synthesized from various sources, due to the well-defined textural properties coupled with surface chemistry of STL-AC which fa- vors aspirin adsorption. The results demonstrate the potential of STL-AC as aspirin adsorbent.

Microstructure and remarkably improved hydrogen storage properties of Mg_2Ni alloys doped with metal elements of Al, Mn and Ti

Mg2Ni0.7M0.3(M=Al,Mn and Ti)alloys were prepared by solid phase sintering process.The phases and microstructure of the alloys were systematically characterized by XRD,SEM and STEM.It was found that Mg3MNi2intermetallic compounds formed in Mg2Ni0.7M0.3alloys and coexisted with Mg and Mg2Ni,and that radius of M atoms closer to that of Mg atom was more beneficial to the formation of Mg3MNi2.The hydrogen storage properties and corrosion resistance of Mg2Ni0.7M0.3alloys were investigated through Sievert and Tafel methods.Mg2Ni0.7M0.3alloys exhibited remarkably improved hydrogen absorption and desorption properties.Significantly reduced apparent dehydriding activation energy values of-46.12,-59.16and-73.15kJ/mol were achieved for Mg2Ni0.7Al0.3,Mg2Ni0.7Mn0.3and Mg2Ni0.7Ti0.3alloys,respectively.The corrosion potential of Mg2Ni0.7M0.3alloys shifted to the positive position compared with Mg2Ni alloy,e.g.there was a corrosion potential difference of0.110V between Mg2Ni0.7Al0.3alloy(-0.529V)and Mg2Ni(-0.639V),showing improved anti-corrosion properties by the addition of Al,Mn and Ti.

Physically literate and physically educated:A rose by any other name?

In the 2013 release of the U.S. National Physical Education Standards the term ＂physically literate＂ replaced ＂physically educated＂. Un- fortunately, most discourse within the profession about the term physically literate occurred primarily after its adoption. While we agree with the spirit and intent of the term, we feel it is essential to discuss not only what has been potentially gained but also lost. In our paper, we illustrate the similarity of the terms physically educated and physically literate and essentially, from a definitional perspective, find little difference--but are these terms interchangeable？ We provide a critical review of the standards and conclude that the change to physical literacy has produced a shift away from psychomotor outcomes to cognitive outcomes. Our concerns about this are many, but most importantly they are about the need to emphasize the ＂physical＂ in physical education （PE）. It is our belief that the key to elevating the profession and maintaining and increasing support for PE is in its ability to promote and provide physical activity. Without physical activity and physical fitness as main outcomes, PE increases its vulnerability to extinction as a standard part of the U.S. K-12 education curriculum.

Magneto-hydrodynamic flow of squeezed fluid with binary chemical reaction and activation energy

The present exploration is conducted to describe the motion of viscous fluid embedded in squeezed channel under the applied magnetics effects.The processes of heat and mass transport incorporate the temperature-dependent binary chemical reaction with modified Arrhenius theory of activation energy function which is not yet disclosed for squeezing flow mechanism.The flow,heat and mass regime are exposed to be governed via dimensionless,highly non-linear,ordinary differential equations (ODEs) under no-slip walls boundary conditions.A well-tempered analytical convergent procedure is adopted for the solutions of boundary value problem.A detailed study is accounted through graphs in the form of flow velocity field,temperature and fluid concentration distributions for various emerging parameters of enormous interest.Skin-friction,Nusselt and Sherwood numbers have been acquired and disclosed through plots.The results indicate that fluid temperature follows an increasing trend with dominant dimensionless reaction rate σ and activation energy parameter E.However,an increment in σ and E parameters is found to decline in fluid concentration.The current study arises numerous engineering and industrial processes including polymer industry,compression and injection shaping,lubrication system,formation of paper sheets,thin fiber,molding of plastic sheets.In the area of chemical engineering,geothermal engineering,cooling of nuclear reacting,nuclear or chemical system,bimolecular reactions,biochemical process and electrically conducting polymeric flows can be controlled by utilizing magnetic fields.Motivated by such applications,the proposed study has been developed.