急性运动降低感染风险的免疫调节机制

由于新型冠状病毒(2019-nCoV)感染的肺炎疫情暴发,人们将居家运动作为提高免疫力与保持健康的重要手段,运动与免疫的关系再度受到关注。一般认为,在充分恢复的前提下进行规律的中高强度运动可提高免疫功能,而急性运动(acute exercise)可能抑制免疫功能并增加感染风险。急性运动后外周血淋巴细胞计数及功能降低、免疫球蛋白A水平分泌减少被认为是运动抑制免疫的理论基础。但目前这种独立于非运动因素影响免疫功能增加感染风险的认识受到了现有研究的挑战。急性运动可通过应激反应将淋巴细胞亚群迅速动员至循环中,运动结束后,淋巴细胞亚群又会迅速迁移至外周组织。淋巴细胞的重新分布(lymphocyte redeployment)可能是一种进化保守的免疫机制,这一过程强化了外周组织的免疫监视与调节功能,有助于提升机体抵抗感染能力。因此,从这一视角就急性运动对机会性感染风险及免疫功能影响的现状进行综述。     

Should Science be Taught in Early Childhood?

This essay considers the question of why we should teach science to K-2. After initial consideration of two traditional reasons for studying science, six assertions supporting the idea that even small children should be exposed to science are given. These are, in order: (1) Children naturally enjoy observing and thinking about nature. (2) Exposing students to science develops positive attitudes towards science. (3) Early exposure to scientific phenomena leads to better understanding of the scientific concepts studied later in a formal way. (4) The use of scientifically informed language at an early age influences the eventual development of scientific concepts. (5) Children can understand scientific concepts and reason scientifically. (6) Science is an efficient means for developing scientific thinking. Concrete illustrations of some of the ideas discussed in this essay, particularly, how language and prior knowledge may influence the development of scientific concepts, are then provided. The essay concludes by emphasizing that there is a window of opportunity that educators should exploit by presenting science as part of the curriculum in both kindergarten and the first years of primary school.     

A Process Approach to Community-Based Education: The People’s Free University of Saskatchewan

On the basis of insights provided by Whitehead and John Cobb, I show how the People’s Free University of Saskatchewan (PFU) is a working model of free, open, community-based education that embodies several characteristics of Whitehead’s philosophy of education. Formed in opposition to the growing commercialization at the original “people’s university,” (the University of Saskatchewan) the PFU has spawned distinctive ideals of its own. The PFU reflects Whitehead’s belief in the importance of shared knowledge fostered by community-based education, the value of abstract and practical knowledge, and the power of the imagination to establish a community of learners capable of acting freely together.     

Envisioning Possibility: Schooling and Student Agency in Children’s and Young Adult Literature

This article provides a rationale for using literature in the classroom to explore conceptions of curriculum and teaching. We discuss a number of exemplars from children’s and young adult fiction, both mainstream and less well known; offer a taxonomy for categorizing the range of visions of curriculum and teaching in the literature; and describe the responses of a group of middle school students to a unit that examined schooling in literature. We argue that reading literature which addresses student experiences in school can help students make sense of those experiences and, more importantly, open their minds to ideas about teaching and schooling that they otherwise might never have considered.John Kornfeld is Professor and Director of Graduate Studies in the School of Education at Sonoma State University. His research in curriculum, children’s literature, school/ university collaboration, and the politics of schooling has been published in such journals as Theory into Practice, Social Education, and Theory and Research in Social Education.Laurie Prothro is a school library consultant and children’s librarian in Sonoma County, California. She specializes in collection development and young adult literature. Her most recent publication with John Kornfeld, entitled “Comedy, Conflict, and Community: Home and Family in Harry Potter,” appears in Elizabeth Heilman’s Harry Potter’s World: Multidisciplinary Critical Perspectives.     

2019-nCoV疫情期间封闭管训对省级运动项目中心冬训运动员心境影响的分析

目的：通过对第一手资料的描述与分析,探究冬训期间,2019-nCoV(新型冠状病毒)疫情影响下的完全封闭式管理与训练对运动员心境变化的影响。方法：使用简式心境量表(POMS)对我国南方某省重竞技项目中心217名运动员在疫情爆发前后进行为期4周的心境监控。结果：不同性别运动员的TMD(Total Mood Disturbance )分数存在显著差异(p=0.000);不同运动项目(跆拳道、柔道、拳击、古典式摔跤和自由式摔跤)运动员的TMD分数存在显著差异(p=0.000);不同强度下运动员的分数存在显著差异(p=0.002)。封闭式管训之后,运动员的疲劳分数(p=0.000)和自尊分数(p=0.021)显著低于封闭管训之前,精力分数有下降的趋势。结论：训练强度对疲劳感影响显著,而重大公共疫情及相应的封闭式管训可能引起运动员自尊水平下降,进而导致其他消极情绪的上升。     

La Medusa by Caravaggio: characterisation of the painting technique and evaluation of the state of conservation

The oil painting “La Medusa” executed by Caravaggio at the end of the XVI century on a wooden shield, was investigated by integrated physical–chemical and analytical methodologies in order to obtain scientific data capable of elucidating the state of conservation and the painting technique. Optical (OM) and electronic (SEM-EDS) microscopy, micro-FT-IR spectroscopy, gas chromatography–mass spectrometry (GC–MS) and pyrolysis GC–MS were applied on two microfragments and some organic samples obtained by solvent extraction using the swab cleaning technique. The obtained results indicated that Caravaggio probably reused an old shield as a previous gypsum preparation layer has been detected under the original painting layers. He used white lead, natural earths, verdigris and lead–tin yellow type I mixed with drying oils to paint. The considerable amount of amorphous particles of copper chlorides found in the green pigment verdigris suggests that it could have been produced according to the ancient recipe of verde salsum described by Theophilus. Mordant gilding has been identified on the upper part of the shield that can be related to an abandoned experiment to give the painting a mirror-like reflecting effect. Three different varnishes layers have been detected above the painted surface. The original and restoration varnishes have been identified and they contain a mixture of drying oil, mastic and turpentine and some beeswax. Cleaning tests, performed with different organic solvents, suggest the use of isopropyl alcohol as cleaning agent because it is less efficient in comparison to others solvents; thus it ensures a careful and controlled removal of the varnishes.     

‘Index for Inclusion’: a framework for school review in the United Arab Emirates

This study uses the ‘Index for Inclusion’, developed by Booth and Ainscow, as a framework for investigating inclusive provision in the United Arab Emirates (UAE), introduced through the ‘School for All’ initiative. The study, by Nadera Emran Alborno of the American University in Dubai and Eman Gaad of the British University in Dubai, adopts a qualitative research approach, using a multiple case study methodology, to provide a rich and contextualised picture of implementation from the perspective of the various stakeholders. Following the ‘Index for Inclusion’, the findings are presented in terms of the three key school dimensions of cultures, policies, and practices. Themes emerging from the data include barriers to participation and learning such as the lack of effective training, adequate support services, and inclusive classroom structures. Also included are positive system characteristics such as the welcoming school climate, support among stakeholders, and emerging parent and community involvement. The study provides insights into the possible challenges to the implementation of the ‘Index for Inclusion’ in schools in the UAE.     

CRISPR/Cas: a Nobel Prize award-winning precise genome editing technology for gene therapy and crop improvement

Since it was first recognized in bacteria and archaea as a mechanism for innate viral immunity in the early 2010 s,clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas) has rapidly been developed into a robust, multifunctional genome editing tool with many uses. Following the discovery of the initial CRISPR/Cas-based system, the technology has been advanced to facilitate a multitude of different functions. These include development as a base editor, prime editor, epigenetic editor, and CRISPR interference(CRISPRi) and CRISPR activator(CRISPRa) gene regulators. It can also be used for chromatin and RNA targeting and imaging. Its applications have proved revolutionary across numerous biological fields, especially in biomedical and agricultural improvement. As a diagnostic tool, CRISPR has been developed to aid the detection and screening of both human and plant diseases, and has even been applied during the current coronavirus disease 2019(COVID-19) pandemic. CRISPR/Cas is also being trialed as a new form of gene therapy for treating various human diseases, including cancers, and has aided drug development. In terms of agricultural breeding, precise targeting of biological pathways via CRISPR/Cas has been key to regulating molecular biosynthesis and allowing modification of proteins, starch, oil, and other functional components for crop improvement. Adding to this, CRISPR/Cas has been shown capable of significantly enhancing both plant tolerance to environmental stresses and overall crop yield via the targeting of various agronomically important gene regulators. Looking to the future, increasing the efficiency and precision of CRISPR/Cas delivery systems and limiting off-target activity are two major challenges for wider application of the technology. This review provides an in-depth overview of current CRISPR development, including the advantages and disadvantages of the technology,recent applications, and future considerations.     

To promote,or not to promote fundamental British values? Teachers’ standards,diversity and teacher education

In this article we seek to problematize the presence of the requirement within the teachers’ standards (DfE, 2012), that they ‘should not undermine fundamental British values’ in the context of initial teacher education in England. The inclusion of this statement within the teachers’ code of conduct has made its way from the counter‐terrorism strategy, Prevent and raises questions about Britishness, values and the relationship between the state and the profession more generally. We argue that the inclusion of the phrase within a statutory document that regulates the profession is de facto a politicization of the profession by the state thereby instilling the expectation that teachers are state instruments of surveillance. The absence of any wider debate around the inclusion of the statement is also problematic as is the lack of training for pre‐service and inservice teachers since it means this concept of fundamental British values is unchallenged and its insidious racialising implications are unrecognised by most teachers.     

Physical education teachers’ self-reported use and perceptions of various teaching styles

Increasing recognition of the constructivist nature of learning as well as the diversity of student learning styles highlights the need for teachers to use different teaching styles. Unfortunately, little is known about teachers’ use and perception of various teaching styles. The purpose of this study was to explore physical education teachers’ self-reported use and perceptions of various teaching styles. Participants were 212 physical education teachers representing a variety of elementary and secondary school settings. Teachers had significantly different experiences in the use and perceptions of the different teaching styles. Their perceptions also differed according to self-rated teaching ability related to using the styles.