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.     

Is Criminology Out-of-Date? A Research Note on the Use of Common Types of Data

There is a need to explore trends in data use by researchers in criminology to assess the limitations of the knowledge base in the discipline. The current study explores the use of data published in three top criminology journals over a 10-year period to review: (1) data types (primary, secondary, or both), (2) the age of the data, and (3) whether scholars using data at least a decade old mention it as a limitation. The study found that the time dimension of data varied by publication source. A heavy reliance on secondary data was observed across all journals. Studies using only secondary data tended to have older data on average when compared to other data types. A majority of articles using data at least a decade old did not mention it is a shortcoming. The paper concludes by discussing advantages and disadvantages of relying on secondary data within the discipline of criminology.     

Play Roof (Ⅱ)——A New Kind of Playground

That was Tuesday, and all the rest of the week Jack and Sally were very busy. First they took the tickets around to all the families in the twobuildings. That was easy after they'd rung the first few doorbells. Miss Fid-     

Goldie in London(Ⅱ)

作为伦敦市的标志以及英国的象征,大本钟巨大而华丽,重13.5吨, 四个钟面的面积有两平方米左右。大本钟从1859年就为伦敦城报时,至今将近一个半世纪,尽管这期间大本钟因两度裂开而重铸,但现在大本钟的钟声仍然清晰、动听。     

Effects of angiotensin Ⅱ on connexin 43 of VSMCs in arteriosclerosis

Objective： To observe the effect ofangiotensin Ⅱ （Ang Ⅱ） on expression of gap junction channel protein connexin 43 （Cx43） in the proliferation process of vascular smooth muscle cells （VSMCs） during the early stage of arteriosclerosis. Methods： Thirty-two adult male rabbits were randomly divided into 4 groups. Rabbits in Group A were fed common diet while others in Groups B, C, and D were fed high-cholesterol diet. Losartan （10 mg/（kg.d）） and ramipril （0.5 mg/（kg-d）） were added in the diet of Groups C and D, respectively. The animals were sacrificed after 8 weeks and abdominal aortas were removed and dissected. The expression of Cx43 was assayed using RT-PCR and Western Blotting analysis. Results： Cx43 was increased markedly in both protein and mRNA level in Groups B, C, and D fed high-cholesterol diet compared with that in control group （P〈0.01）. Cx43 level in losartan or ramipril treated groups was higher than that in control group （P〈0.01, P〈0.05）, but lower than that in high-cholesterol diet groups （P〈0.05, P〈0.01）. Conclusion： Cx43 level was upregulated in VSMCs during early atherosclerosis. Losartan and ramipril can inhibit the expression of Cx43.     

A Note on Global Convergence Result for Conjugate Gradient Methods

We extend a results presented by Y.F.Hu and C.Storey(1991)^[1] on the global convergence rsult for conjugate gradient methods with different choices for the parameter βk.In this note,the conditions given on βk are milder than that used by Y.F.Huang C.Storey.     

The Intellectual Structure of Research on Educational Technology in Science Education (ETiSE): A Co-citation Network Analysis of Publications in Selected Journals (2008–2013)

The main purpose of this paper is to investigate the intellectual structure of the research on educational technology in science education (ETiSE) within the most recent years (2008–2013). Based on the criteria for educational technology research and the citation threshold for educational co-citation analysis, a total of 137 relevant ETiSE papers were identified from the International Journal of Science Education, the Journal of Research in Science Teaching, Science Education, and the Journal of Science Education and Technology. Then, a series of methodologies were performed to analyze all 137 source documents, including document co-citation analysis, social network analysis, and exploratory factor analysis. As a result, 454 co-citation ties were obtained and then graphically visualized with an undirected network, presenting a global structure of the current ETiSE research network. In addition, four major underlying intellectual subfields within the main component of the ETiSE network were extracted and named as: (1) technology-enhanced science inquiry, (2) simulation and visualization for understanding, (3) technology-enhanced chemistry learning, and (4) game-based science learning. The most influential co-citation pairs and cross-boundary phenomena were then analyzed and visualized in a co-citation network. This is the very first attempt to illuminate the core ideas underlying ETiSE research by integrating the co-citation method, factor analysis, and the networking visualization technique. The findings of this study provide a platform for scholarly discussion of the dissemination and research trends within the current ETiSE literature.     

Availability and toxicity of Fe(Ⅱ) and Fe(Ⅲ) in Caco-2 cells

The objective of the present study was to compare the toxicity and availability of Fe(Ⅱ) and Fe(Ⅲ) to Caco-2 cells.Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) release. The activities of two major antioxidative enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and differentiation marker (alkaline phosphatase) were determined after the cells were exposed to different levels of iron salts. The cellular iron concentration was investigated to evaluate iron bioavailability. The results show that iron uptake of the cells treated with Fe(Ⅱ) is significantly higher than that of the cells treated with Fe(Ⅲ) (P＜0.05). Fe(Ⅱ) at a concentration>1.5 mmol/L was found to be more effective in reducing cellular viability than Fe(Ⅲ). LDH release investigation suggests that Fe(Ⅱ) can reduce stability of the cell membrane. The activities of SOD and GPx of the cells treated with Fe(Ⅱ) were higher than those of the cells treated with Fe(Ⅲ), although both of them increased with raising iron supply levels. The results indicate that both Fe(Ⅱ) and Fe(Ⅲ) could reduce the cellular antioxidase gene expression at high levels.     

Adsorption of Pb(Ⅱ) on Sediment of the Dianshan Lake: Adsorption Models and Kinetics

1　Introduction　Pb ,oneofthetoxicmetals,isharmfultohealthforhumanbeings ,especially ,forchildren .Inindividualsofallages ,Pbmaycausemanyseriousdiseasesin cludinganemia ,braindamage ,impairedfunctionoftheperipheralnervoussystem ,reproductiveabnor malities,etc[1,2 ] .Inthelate 1970s,ashiftfromPbpoisoningtreatmenttoPbpoisoning preventionoc curred[3] .Therefore ,anunderstandingofthecondi tionsandmechanismsthatregulatethemobilizationanddistributionofPbintheenvironmentisessential.　Pbfindsitswayt…     

Note on a cross‐cultural test of Gilligan's ethic of care1

One hundred and twenty students from both Brazil and Norway were tested with Skoe's Ethic of Care Interview (ECI), which is a test of Gilligan's hypothesized gender‐related ethic of care. Subjects were also tested with Bem's Sex Role Inventory and Triandis's Test of Cultural Orientations. The ECI was shown to be related neither to gender nor to sex‐role concepts, and lower ECI scores from the Brazilian sample could be related to their higher collectivism scores on Triandis's test. The results suggest that Gilligan's ethic of care, as tested by the ECI, is not gender‐related and may be culture specific.     

A general history of the research on Chinese academies (1923–2007)

Research on traditional Chinese academies has aroused interest ever since its existence. At least 2 302 papers and over 162 books concerning traditional academic institutions have been published for over 85 years from 1923 to 2007. Consisting of the following four phases as initial development (1923–1949), continual progress (1950–1979), vigorous prosperity (1980–1993) and new tendency in the new century (2000–2007), this paper discusses the characteristics, central issues and research trends of each phase and introduces the main achievements, which are worthy to be noted and discussed. __________ Translated from Hunan Daxue Xuebao (Shehui Kexue Ban) 湖南大学学报 (社会科学版), Journal of Hunan University (Social Sciences), 2007, 21(3): 31–40