教材选文的拟题应慎重——人教版四年级上册《卡罗纳》一文的拟题指瑕

教材选文,一定是编者根据《语文课程标准》,结合具体的学段,精心选择与编排的。对于小学语文教学而言,教材选文直接关系到学生语文学力的发展。因为,典范式的选文对小学生语文知能与智能的形成起着十分重要的作用。

《卡罗纳》教学设计

(1)认识文章中的“遭、悯、咛、咐、啕”5个生字。(2)读懂课文内容,激发关爱他人,帮助他人的情感(3)抓住人物语言、动作、神态、心理活动描写,通过品读、交流,感受人物的内心情感。教学重点:抓住人物语言、动作、神态、心理活动描写,通过品读、交流,感受人物的内心情感。

Effect of Al and Si additions on microstructure and mechanical properties of TiN coatings

Ti-X-N (X=Al,Si or Al+Si) coatings were grown onto cemented carbide substrates by cathodic arc evaporation. The hardness of the coatings was obtained by nanoindentation and the microstructure was investigated by XRD,XPS and SEM. Solid solution hardening results in a hardness increase from 24 GPa for TiN to 31.2 GPa for TiAlN. The higher hardness values of 36.7 GPa for TiSiN and 42.4 GPa for TiAlSiN are obtained by the incorporation of Si into TiN (TiAlN) coatings due to the formation of special three-dimensional net structure consisting of nanocrystalline (nc) TiN (TiAlN) encapsulated in an amorphous (a) Si3N4 matrix phase. Furthermore,the nc-TiAlN/a-Si3N4 coating shows the best machining performance.

Is proximity to oil refinery a big factor in explaining differences in gas prices？

According to the Energy Information Administration, average retail gasoline prices tend to typically be higher in certain states than in others. Aside from taxes, the factors shown to contribute to regional and even local differences in gasoline prices include proximity of supply, supply disruptions, competition in the local market and environmental programs. Of interest in this paper is proximity of supply. It has been hypothesized that areas farthest from the Gulf Coast （the source of nearly half of the gasoline produced in the United States and, thus, a major supplier to the rest of the country） tend to have higher prices. To test this hypothesis, the paper assembles state level monthly retail gasoline data for the period 1983 to 2007 for five states with oil refineries （Alabama, Georgia, Texas, Mississippi and Louisiana） and five states without refineries （Arkansas, Tennessee, North Carolina, South Carolina and Florida）. The analysis employs dynamic correlation, regression, cointegration and vector autoregressive methods. Overall, the results show that retail gas prices in states with refineries and those without refineries tend to move in the same direction over time. The small differences observed over time may suggest that price shocks take a short time to be felt nationwide.

Genetic Variation and Heritability Estimates for Bunch Yield, Bunch Components and Vegetative Traits in Oil Palm Interspecific Hybrids

Progeny testing of oil palm interspecific hybrids was conducted in four trials in Kluang, Ulu Paka, Teluk Intan and Carey Island, Malaysia. The interspecific hybrids （O × P） were created according to the North Carolina Model I （NCM I） mating design, using Elaeis oleifera （0） and Elaeis guineensis var. pisifera （P） as the maternal and paternal parents, respectively. Differences among O, P and O-within-P were determined by the performance （bunch yield, components and vegetative traits） of the progenies. There were significant differences among P for fresh fruit bunch （FFB） yield, bunch number （BN） and average bunch weight （ABW） in Kluang, Ulu Paka and Teluk Intan, but not in Carey Island. FFB yield was generally higher on coastal soils （Teluk Intan and Carey Island） than inland soils （Kluang and Ulu Paka）. Heritability was calculated based on the intraclass correlation. Heritability estimates for these three yield components were variable, depending on the breeding material and environment in which the materials were tested. Fruit to bunch （F/B） and oil to bunch （O/B） of parthenocarpic fruits were important in determining the overall O/B of the interspecific hybrids. The O x P hybrids in Kluang showed the lowest height increment with only a mean of 14.0 cm/year, whereas in Ulu Paka and Teluk Intan, the values were higher at 24.0 cm/year and 25.0 cm/year, respectively. The study showed that the FFB yields ofoil palm interspecific hybrids performed better in coastal soils than inland soils.

A Reflection of Minimum Adequate Education in South Carolina More Than Fifty Years Later

The issues and challenges of minimum adequate public school education in the State of South of South Carolina has been a struggle between lawmakers and taxpayers for more than fifty years. The enactment of the Civil Rights Act of 1964 led to forced school integration, busing, and led to whites＇ physical moving out of selected school districts. Selected public schools filed a lawsuit against the State of South Carolina to the Supreme Court with the claim of failing to provide adequate and equal education to all children in the state. This reflection focuses on the Abbeville case in context, funding issues, and inadequate facilities, which concludes with a reflective view of the Brown v. The Board of Edueation 1954 decision.

Monte Carlo method in optical atomic force microscopy

Scanning probe microscopy(SPM)is a branch of microscopy that forms images of surfaces using a physical probe that scans the specimen.Atomic force microscopy is one of the SPM family which is considered as a very versatile tool for surface imaging and measurements.A wide range of various samples can be measured regardless of being conductive,no-conductive,in vacuum,in air or in a fluid as a unique feature.One of the most challenges in atomic force microscopes(AFMs)is to evaluate the associated uncertainty during the surface measurements by AFMs.Here,an optical AFM is calibrated through the calibration of XYZ stage.The approach is to overcome difficulties experienced when trying to evaluate some uncertainty components which cannot be experimentally determined i.e.tip surface interaction forces and tip geometry.The Monte Carlo method is then used to determine the associated uncertainties due to such factors by randomly drawing the parameters according to their associated tolerances and their probability density functions(PDFs).The whole process follows supplement 2 to“the guide to the expression of the uncertainty in measurement”(GUM).The approach validated in the paper shows that the evaluated uncertainty in AFM is about 10 nm.

Managing hybridization of a recovering endangered species： The red wolf Canis rufus as a case study

Hybridization presents a unique challenge for conservation biologists and managers. While hybridization is an important evolutionary process, hybridization is also a threat formany native species. The endangered species recovery effort for the red wolf Canis rufus is a classic system for understanding and addressing the challenges of hybridization. From 1987-1993, 63 red wolves were released from captivity in eastern North Carolina, USA, to establish a free-ranging, non-essential experimental population. By 1999, managers recognized hybridization with invasive coyotes Canis latrans was the single greatest threat to successful recovery, and an adaptive management plan was adopted with innovative approaches for managing the threat of hybri- dization. Here we review the application and results of the adaptive management efforts from 1993 to 2013 by comparing： （1） the numbers of wolves, coyotes, and hybrids captured, （2） the numbers of territorial social groups with presumed breeding capabili- ties, （3） the number of red wolf and hybrid litters documented each year and （4） the degree of coyote introgression into the wild red wolf gene pool. We documented substantial increases in the number of known red wolves and red wolf social groups from 1987-2004 followed by a plateau and slight decline by 2013.The number of red wolf litters exceeded hybrid litters each year and the proportion of hybrid litters per year averaged 21%. The genetic composition of the wild red wolf population is estimated to include 〈 4% coyote ancestry from recent introgression since reintroduction. We conclude that the adaptive management plan was effective at reducing the introgression of coyote genes into the red wolf population, but population recovery of red wolves will require continuation of the current management plan, or alternative approaches, for the foreseeable future. More broadly, we discuss the lessons learned from red wolf adaptive management that could assist other endangered species recovery efforts facing the challenge of minimizing hybridization [Current Zoology 61 （1）： 191-205, 2015 ].

Sediment Pollution Assessment of Abandoned Residential Developments Using Remote Sensing and GIS

The current economic crisis has left numerous residential developments in the southeastern United States in various stages of construction. Many of them are currently graded and essentially abandoned, creating a major source of sediment runoff to waterways. Residential development locations with significant bare soil areas were identified through classification of Landsat 5 TM satellite imagery and subsequently verified from high-resolution county aerial photographs. The revised universal soil loss equation (RUSLE) was used in a geographic information system (GIS) as a tool for prioritizing identified locations on the basis of potential soil loss assuming the worst case scenario of a completely unmaintained site. Initial GIS identification indicated 301 sites with a total bare soil area of 2 378 ha over three counties in Upstate South Carolina. A random sample of 153 sites was visited over 17 days and assessed using a mobile GIS, global positioning system (GPS), and digital camera for field validation. Results indicated that 78% (119) of the sites were classified correctly (residential construction sites in varying stages of completion); 88% of identified areas were less than 25% built compared to the previous year; 48% were categorized as moderate to severe problems. Abandoned and unfinished developments in Upstate South Carolina may represent a major source of sediment pollution to streams. Well-maintained erosion control devices may be useful in preventing offsite sedimentation.

Theoretical investigation on tunneling magnetoresistance in ferromagnetic/anti-ferromagnetic core/shell system

Based on Monte Carlo simulations,the effect of structural configuration on the hysteresis behavior and tunneling magnetoresistance(TMR) of composite nanoparticles with ferromagnetic(FM) core/anti-ferromagnetic(AFM) shell is investigated.The simulated results indicate that the coercive field(H c) of composites increases with the decreasing ratio of core-radius(r core) to shell-radius(r shell).When the ratio of r shell to r core is approaching 4:3,H c decreases with increasing AFM thickness.In addition,TMR is found to increase with the decreasing ratio of r core to r shell,resulting from the enhancement of resistance changes in disordered AFM shell.