60CO-γ射线对枳种子辐射生物学效应的探讨

本文研究了^60Co-γ射线对枳种子的辐射生物学效应，结果表明：^60Co-γ射线对枳的发芽、出苗和生长的抑制随着剂量的加大而增强，相对电导率也随剂量的加大而增加，各处理都能不同程度地诱导白化苗、畸形苗等变异性状的产生。辐射半致死剂量(LD50)为9KR左右，临界剂量(LD40)在7KR附近．     

The body donation program at the Federal University of Health Sciences of Porto Alegre: A successful experience in Brazil

The use of dissection to study human anatomy is the foundation for educational excellence among future health professionals, as it offers an ideal opportunity to learn the body's morphology in three dimensions while also providing students with a more humanistic education. The shortage of bodies for dissection, combined with the Brazilian population's lack of knowledge concerning the possibility of voluntarily donating their own bodies, led to the creation of the Body Donation Programs for Education and Research in Anatomy at the Federal University of Health Sciences of Porto Alegre (UFCSPA). The program is based on three pillars: Informing the general public about the program, donor registration, and donation itself. Since the creation of the donor program in 2008, there has been an increase in both the number of donations made during donor's lifetime and the number of bodies received by the university. There has also been a shift in relation to the origin of these bodies, as before the creation of the program most bodies were unclaimed cadavers, while today most of the bodies are sourced from voluntary donations. The initial results regarding the public's acceptance of the possibility of making body donations have been encouraging, as shown by the annual growth in donor registrations. Consequently, the quality and quantity of the material available for educational purposes have greatly improved. Anat Sci Educ. © 2013 American Association of Anatomists.     

Software and Scanner: A Comparison of Procedures in University of California,San Diego's Interlibrary Loan and Course Reserves Units

The Document Delivery Services/Interlibrary Loan Unit and the Course Reserves Unit at the University of California, San Diego's Access Services Department both utilize the Konica Minolta PS7000 book scanner to deliver requested documents and post electronic reserve items. Though the hardware is the same in both units, unique service goals and software—Ariel Interlibrary Loan Document Transmission Software for DDS/ILL and Adobe Photoshop for Course Reserves—result in different issues and challenges. This article discusses the shared practices of the Document Delivery Services/Interlibrary Loan and Course Reserves Units and how each unit utilizes the Konica Minolta PS7000 book scanner to offer better service for their patrons.     

Quantifying the interdisciplinarity of scientific journals and fields

There is an overall perception of increased interdisciplinarity in science, but this is difficult to confirm quantitatively owing to the lack of adequate methods to evaluate subjective phenomena. This is no different from the difficulties in establishing quantitative relationships in human and social sciences. In this paper we quantified the interdisciplinarity of scientific journals and science fields by using an entropy measurement based on the diversity of the subject categories of journals citing a specific journal. The methodology consisted in building citation networks using the Journal Citation Reports^® database, in which the nodes were journals and edges were established based on citations among journals. The overall network for the 11-year period (1999–2009) studied was small-world and followed a power-law with exponential cutoff distribution with regard to the in-strength. Upon visualizing the network topology an overall structure of the various science fields could be inferred, especially their interconnections. We confirmed quantitatively that science fields are becoming increasingly interdisciplinary, with the degree of interdisplinarity (i.e. entropy) correlating strongly with the in-strength of journals and with the impact factor.     

No Poor Child Left Unrecruited: How NCLB Codifies and Perpetuates Urban School Militarism

A critical theoretical framework is used to analyze the No Child Left Behind (NCLB) federal legislation and its role in codifying and perpetuating educational practices and policies that contribute to growing campus militarism in urban schools serving low-income African American and Latino students. The author argues that NCLB § 9528 is part of a broader strategy by the Pentagon to recruit low-income urban youth for the military. The article examines how NCLB's focus on standardized tests and punitive sanctions reinforces urban schools' already narrow curriculum, leading to the diminished capacity of students to question militarism and challenge social oppression.     

Traffic modeling for communications networks: A multifractal approach based on few parameters

In this work, in order to model network traffic processes, an efficient multifractal model is proposed based on fewer parameters than other models present in the literature, called 2PEMV. The 2PEMV model (2-Parameter Exponential Modeling for Multipliers’ Variance) is based on a multiplicative cascade in the wavelet domain capable of synthesizing communication network traffic traces which present characteristics such as self-similarity and wide Multifractal Spectrum Width (MSW). For such a purpose, in the 2PEMV model, the energy decay of the wavelet coefficients is captured by means of an exponential modeling for the multipliers’ variance along the cascade scales. The performance of the 2PEMV model to represent the network traffic characteristics is evaluated in comparison to other models present in the literature through simulations that are carried out using real communication network traffic traces.     

Web and social media usage by museums: Online value creation

This paper contributes to the understanding of online strategies in the context of museums as examples of cultural organisations, an underrepresented sector in the information management literature. It presents a theoretical framework for understanding the online strategies of museums’ use of Web and social media, their sources of online value (efficiency, novelty, lock-in, complementarities) and some measurements of Internet performance, such as the Alexa Internet ranking and the number of followers of museums in social media. This type of analysis has not been conducted before and the findings will help museum curators and managers of other cultural institutions to appreciate the impact of these technologies and to make better informed decisions regarding online strategies and resource allocation. In addition, the results of this research are applicable to similar organisations, such as archives and cultural exhibitions, as well as to other service organisations related to information, education and entertainment activities.     

Intermittent hypoxia exposure in a hypobaric chamber and erythropoietin abuse interpretation

Abstract

The aim of this study was to assess the effect of intermittent hypoxia exposure on direct and indirect methods used to evaluate recombinant human erythropoietin (rhEPO) misuse. Sixteen male triathletes were randomly assigned to either the intermittent hypoxia exposure group (experimental group) or the control normoxic group (control group). The members of the experimental group were exposed to simulated altitude (from 4000 to 5500 m) in a hypobaric chamber for 3 h per day, 5 days a week, for 4 weeks. Blood and urine samples were collected before and after the first and the final exposures, and again 2 weeks after the final exposure. While serum EPO significantly increased after the first [from a mean 8.3 IU · l^?1 (s = 3.2) to 16.6 IU · l^?1 (s = 4.7)] and final exposures [from 4.6 IU · l^?1 (s = 1.4) to 24.8 IU · l^?1 (s = 9.3)], haemoglobin, percentage of reticulocytes, and soluble transferrin receptor were not elevated. Second-generation ON/OFF models (indirect rhEPO misuse detection) were insensitive to intermittent hypoxia exposure. The distribution of the urinary EPO isoelectric profiles (direct rhEPO misuse detection) was altered after intermittent hypoxia exposure with a slight shift towards more basic isoforms. However, those shifts never resulted in misinterpretation of results. The intermittent hypoxia exposure protocol studied did not produce any false-positive result for indirect or direct detection of rhEPO misuse in spite of the changes in EPO serum concentrations and urinary EPO isoelectric profiles, respectively.     

An innovative concept map approach for improving students' learning performance with an instant feedback mechanism

Concept maps have been widely employed for helping students organise their knowledge as well as evaluating their knowledge structures in a wide range of subject matters. Although researchers have recognised concept maps as being an important educational tool, past experiences have also revealed the difficulty of evaluating the correctness of a concept map. It usually takes days or weeks for teachers to manually evaluate the concept maps developed by students; consequently, the students cannot receive timely feedback from the teachers, which not only affects their learning schedules, but also significantly influences the students' learning achievements. In this paper, a computer‐based concept map‐oriented learning strategy with real‐time assessment and feedback is proposed in order to cope with the problems mentioned above. Our approach provides immediate evaluation of concept maps and gives also real‐time feedback to the students. An experiment has been conducted to evaluate the effectiveness of this new strategy in comparison with the conventional computer‐based concept map approach. It is found that our innovative approach can be significantly beneficial to promote learning achievements as well as the learning attitudes of students.