赛题别解

题目Suppose real numbers x and ysatisfy 2x^2 - 2xy q- y^2 = 1, then the valuerange for a： q- 2y is（ ）（A） [- 5,5].     

PEP Bookl Unit 6 Part A Let＇s Learn

教学目标：1．认知目标：（1） Enable the students to listen, say and read the ten numbers （one-ten）。 （2） Listen and do： Show me 1 and 2…… （3）Try to sing： Ten Little Candles Dance     

假期乐园

I. Number Game
Look at the four ellipses（椭圆）. There are nine numbers（from one to nine） on them. Please exchange two of the numbers their places and make the four numbers＇ summation（总和） the same on the every ellipse. Can youfind them out？     

《新标准英语》第三册Module 4 Unit 1

教学片段一:热身,激趣1.Greeting:songs and chants2.Warming-up:Numbergame:(1)Count1-12,then12-1;(2)看卡片说数字(First saythe numbers,then add thenumbers)3.Listen and count the     

Properties of Inequalities

The set of real numbers has the property of being ordered： for any numbers a and b we have one and only one of the these relations： a〉b（a is greater than b）, a=b, or a〈b（a is less than b）. The notation a〉b means the difference a-b is positive; the notation a〈b means the difference a-b is negative.     

Edaravone protects PC12 cells from ischemic-like injury via attenuating the damage to mitochondria

Background： Edaravone had been validated to effectively protect against ischemic injuries. In this study, we investigated the protective effect of edaravone by observing the effects on anti-apoptosis, regulation of Bcl-2/Bax protein expression and recovering from damage to mitochondria after OGD （oxygen-glucose deprivation）-reperfusion. Methods： Viability of PC 12 cells which were injured at different time of OGD injury, was quantified by measuring MTT （2-（4,5-dimethylthia-zol-2-yl）-2,5-diphenyltetrazolium bromide） staining. In addition, PC 12 cells＇ viability was also quantified after their preincubation in different concentration of edaravone for 30 min followed by （OGD）. Furthermore, apoptotic population of PC 12 cells that reinsulted from OGD-reperfusion with or without preincubation with edaravone was determined by flow cytometer analysis, electron microscope and Hoechst/Pl staining. Finally, change of Bcl-2/Bax protein expression was detected by Western blot. Results： （1） The viability of PC12 cells decreased with time （1-12 h） after OGD. We regarded the model of OGD 2 h, then replacing DMEM （Dulbecco＇s Modified Eagle＇s Medium） for another 24 h as an OGD-reperfusion in this research. Furthermore, most PC 12 cells were in the state of apoptosis after OGD-reperfusion. （2） The viability of PC 12 cells preincubated with edaravone at high concentrations （1, 0.1, 0.01 μmol/L） increased significantly with edaravone protecting PC 12 cells from apoptosis after OGD-reperfusion injury. （3） Furthermore, edaravone attenuates the damage of OGD-reperfusion on mitochondria and regulated Bcl-2/Bax protein imbalance expression after OGD-reperfusion. Conclusion： Neuroprotective effects of edaravone on ischemic or other brain injuries may be partly mediated through inhibition of Bcl-2/Bax apoptotic pathways by recovering from the damage of mitochondria.     

外国数学问题选辑

1. Tom is driving a jeep at a constant speed of 55 MPH. A sports car one-half miles behind Tom is moving at a constant speed, it passes Tom in 60 seconds. How many miles per hour is the speed of the sports car? 2. What is the value of the sum 2~(-1)+2~(-2)+2~(-3)+…+2~(-9)+2~(-10)? Express your answer as a common fraction. 3. The average of twelve different positive integers is 12. What is the greatest possible value of any one of these numbers?     

2011年《数学周报》杯全国初中数学竞赛

一、选择题（每小题7分,共35分）1．A．设口：√7-1．则代数式3a^3＋12a^2-6a-12的值为（ ）． （A）24 （B）25 （C）4√7＋10 （D）4√7＋12 1、B.设x=√5-3/2.则代数式x（x＋1）（x＋2）（x＋3）的值为（ ） （A）0 （B）1 （C）-1 （D）2     

Infection frequency of Epstein-Barr virus in subgingival samples from patients with different periodontal status and its correlation with clinical parameters

Objective： To detect the infection frequencies of different genotypes of Epstein-Barr virus （EBV） in subgingival samples from chronic periodontitis （CP） patients, and to discuss the correlation between infection with EBV and clinical parameters. Methods： Nested-PCR assay was used to detect EBV-1 and EBV-2 in subgingival samples from 65 CP patients, 65 gingivitis patients and 24 periodontally healthy individuals. The amplicons were further identified by restriction fragment length polymorphism analysis （RFLP） with endonucleases Afa I and Stu I. Clinical parameters mainly included bleeding on probing （BOP）, probing depth （PD）, attachment loss （AL） in six sites of the dentition. Results： In CP patients, gingivitis and periodontally healthy individuals, the infection frequencies were 47.7%, 24.6% and 16.7% for EBV-1, and 15.4%, 7.7% and 0% for EBV-2, respectively. In 2 out of the 65 CP patients co-infection of EBV-1 and EBV-2 was found. The positive rate of EBV-1 in chronic periodontitis patients was higher than that in gingivitis patients （P=-0.01） and periodontally healthy individuals （P=-0.01）. But no significant difference was shown in EBV-1 frequency between gingivitis patients and healthy individuals （P〉0.05） or in EBV-2 frequency among the three groups （P〉0.05）. In CP patients, higher mean BOP value was found in EBV-1 or EBV-2 positive patients than that in EBV negative ones （P〈0.01）, but with no statistical difference in the mean PD or AL value between EBV positive and negative patients （P〉0.05）. After initial periodontal treatment, 12 out of the 21 EBV-1 positive CP patients did not show detectable EBV-1 in subgingival samples. Conclusion： nPCR plus RFLP analysis is a sensitive, specific and stable method to detect EBV-1 and EBV-2 in subgingival samples. Subgingival infection with EBV-1 is closely associated with chronic periodontitis. Infection of EBV in subgingival samples was correlated with BOP.     

长江版《牛津英语》3A Unit 3 My school bag

Teaching Aims： 1.Listen and say：What＇s in you school bag？Ihave…2. Grasp the numbers from zero to nine and stationery items. 3. Know plural forms. 4. Guide the pupils to enjoy the happiness of success of using English and train them the ability of listening and speaking.     

Study on the Computational Estimation Performance and Computational Estimation Attitude of Elementary School Fifth Graders in Taiwan

Main purpose of this study is to investigate what level of computational estimation performance is possessed by fifth graders and explore computational estimation attitude towards fifth graders. Two hundred and thirty-five Grade-5 students from four elementary schools in Taipei City were selected for ＂Computational Estimation Test＂ and ＂Computational Estimation Attitude Survey＂. Based on 28 items of the Computational Estimation Test, average number of items correctly answered by students is 16.37, the percent of correct responses is 58.48%, and overall performance is moderate. The Computational Estimation Test includes items representing three number dimensions： whole numbers, decimals and fraction numbers. The data indicate that the number domain of fraction （46.63%） and decimal （54.30%） percent of correct response of the CET （Computational Estimation Test） were relatively low when compared with whole numbers （63.44%）. Based on 35 items of the CEAS （Computational Estimation Attitude Survey）, the mean scores of students＇ CEAS is 119.72, higher than average, indicating that attitude of elementary school fifth graders today to computational estimation is generally positive. As to subscales of elementary school fifth graders＇ attitude to computational estimation, ＂experience in computational estimation＂ component is near negative and passive, indicating that students experience in using computational estimation is somewhat not enough.     

译林新版《英语》三年级下册Unit 5 How old are you?教学

教学过程Step 1.Warming up1.Greet Ss.Show the picture"Welcome to our English class".2.Show a cartoon of the song"Ten little Indian boys"and make Ss familiar with the numbers.T:Let’s enjoy a song together.3.Review numbers.T:What can we learn from the song?The students say the twelve     

Hydrodynamics and oxygen transfer in a novel extra-loop fluidized bed bioreactor

In this paper, the characteristics of fluid mixing time in a novel extra-loop fluidized bed were studied. The results showed that the mixing time was shortened with the increase of fluid velocity. All the discrete numbers of the reactor were above 0.2. The serial number n was 2.5 -3.0. It was judged accordingly that the reactor fluid state was continous stirred tank reactor （CSTR） mainly. When the inspiratory capacity increased the mixing time of the reactor was shortened. Thus the air input was beneficial for the fluid mixing. During the three phases mixing process, the mixing time of the reactor could be decreased by the n increase of carrier and air loading together, but the change was not significant. The parameters affecting the reactor fluid state were fluid velocity, inspiratory capacity and carrier. KLa could be increased with the air loading increase, and at the same gas/liquid ratio when the pressure drop was high, KL~ value was increased. The amount of carrier complex influence on KLa. As the carrier loading continued to increase, its value had been dropped but the changes was not significant, and optimization condition was found at above 800 1 000 g carrier loading （pouzzolane） or 600 g PVC. Under gas/liquid ratio of 0.8% -5.2%, KLa was （0.62-1.37）×10^-2· s^-1.     

Solvability of the nonlinear Airy equation on a torus

1. Introduction Consider the problem (P) below 2 i(), for (,),txxxuuuuufxxtT++++=未a where the initial condition is 0(0,)()uxux=. Herein 0u and 2()fLT are square integrable complex functions on T; T is the 1-dimensional torus, +Ris the set of positive numbers, and a a real positive number. This type of equation was first introduced in the study of optical fibers [1]. Y. Martel [2] proved the well-posedness for the case of whole space R(the set of all real numbers) with a = …     

Psychological type and undergraduate student achievement in pharmacy course in Military Medical University

The Myers-Briggs Type Indicator （MBTI） was given to 264 students in an undergraduate Pharmacy course at a military medical university. Selected MBTI personality types were compared for achievement in the course using a t-test to compare total points earned. High grades were earned by students stronger in the traits of introversion （I） and judgment （J）, whereas the extraverted （E） and perceptive （P） types had the lowest grades and dropped out of the course in the largest numbers. When combinations of MBTI types were compared, the highest grades were earned as follows： IJ 〉 SJ 〉 ST 〉 IS （S： Sensing; T： Thinking; J： Judgment）. This ranking indicates that a sensing personality also has a strong relationship to achievement in this pharmacy course when it is combined with judgment, thinking. Instructors and students need to be aware of the relationship between personality and learning so that they can modify their teaching style and learning behavior to enhance academic achievement.     

具有最少可能边数的唯一k-可染色图的构造

Abstract It was shown that a uniquely vertex k-colorable graph of order n has minimum size n（k - 1） - （^k2）, and a uniquely vertex 3-colorable extremal graph with the minimum degree 3 can be constructed. In this note, we construct-an infinite familyof uniquely vertex k-colorable graphs of the order n, the size n（k - 1） - （^k2） and the minimum degree k by using a recursion method.     

Charlson合并症指数对2型糖尿病肾病死亡率预测作用的研究(英文)简

Our intent is to examine the predictive role of Charlson comorbidity index （CCI） on mortality of patients with type 2 diabetic nephropathy （DN）. Based on the CCI score, the severity of comorbidity was categorized into three grades： mild, with CCI scores of 1-2; moderate, with CCI scores of 3-4; and severe, with CCI scores 〉5. Factors influencing mortality and differences between groups stratified by CCI were determined by logistical regression analysis and one-way analysis of variance （ANOVA）. The impact of CCI on mortality was assessed by the Kaplan- Meier analysis. A total of 533 patients with type 2 DN were enrolled in this study, all of them had comorbidity （CCI score 〉1）, and 44.7% （238/533） died. The mortality increased with CCI scores： 21.0% （50/238） patients with CCI scores of 1-2, 56.7% （135/238） patients with CCI scores of 3-4, and 22.3% （53/238） patients with CCI scores 〉5. Logistical regression analysis showed that CCI scores, hemoglobin, and serum albumin were the potential predictors of mortality （P〈0.05）. One-way ANOVA analysis showed that DN patients with higher CCI scores had lower levels of hemoglobulin, higher levels of serum creatinine, and higher mortality rates than those with lower CCI scores. The Kaplan-Meier curves showed that survival time decreased when the CCI scores and mortality rates went up. In con- clusion, CCI provides a simple, readily applicable, and valid method for classifying comorbidities and predicting the mortality of type 2 DN. An increased awareness of the potential comorbidities in type 2 DN patients may provide insights into this complicated disease and improve the outcomes by identifying and treating patients earlier and more effectively.     

A Note on Vulnerability in Graphs of Diameter Five （ Ⅱ ）

The line persistence of a graph G, Pt （ G ） is the minimum number of lines which must be removed to increase the diameter of G. In Ref. [7] （J. Shanghai Univ., 2003,7（4）：352-357）, we gave a characterization of graphs of diameter five with ρ1 （ G ）≥2. In this paper we will show that each of the 8 special graphs Xi （ i = 1,2,3,4,5,6,7,8） listed in condition （2） of Theorem 1 in Ref. [7] can not be deleted. Therefore the results we obtained in Ref. [7] can not in general be improved.     

Inspiring Questions from the Sea of Examinations——题海拾贝

Bob, Fred, and Vi play a game in which a card numbered 2,3,4,5,6,7,or 8 is stuck to each of their foreheads. Each player can see the other two players＇ numbers but not his or her own. An observ er tells the three players that the three numbers are not all different and that their product is a perfect square（安全平方数）, how many of them can deduce the number on their foreheads？