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1.
Abstract

Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of carnosine have been conducted on skeletal muscle. Given this and the potential for muscle carnosine content to be increased with supplementation, there is now a large body of research examining the ergogenic effects (or otherwise) of carnosine. More recent research, however, points towards a potential for carnosine to exert a wider range of physiological effects in other tissues, including the brain, heart, pancreas, kidney and cancer cells. Taken together, this is suggestive of a potential for carnosine to have therapeutic benefits in health and disease, although this is by no means without complication. Herein, we will provide a review of the current literature relating to the potential therapeutic effects of carnosine in health and disease.  相似文献   
2.
The National Literacy Strategy (NLS) was introduced by the government in the wake of the hotly debated issue of falling educational standards in the UK. All schools were required to adopt the NLS Literacy Hour unless they could show their preferred programme would result in raised levels of achievement. My experience of delivering the Literacy Hour has been a process of adaptation to the needs of my pupils, who are drawn mainly from groups whose language backgrounds differ from that which is dominant in school. I have found that the requirements of NLS, together with many of the commercial resources used to teach it, are not appropriate for pupils from these groups and a question arose: is it the pupils who are in some way deficient or is it the approach and the resources being used? This article takes a case study of the use of a commercially produced resource to explore the model of language implicit in NLS, the kinds of resources it generates and the ways in which this creates failure in pupils from different language backgrounds. It then considers the New Literacy Studies and their implications for an alteration in our approach.  相似文献   
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OBJECTIVES: The objective is to highlight the important role that librarians have in teaching within a successful medical informatics program. Librarians regularly utilize skills that, although not technology dependent, are essential to conducting computer-based research. The Metropolis analogy is used to introduce the part librarians play as informatics partners. Science fiction is a modern mythology that, beyond a technical exterior, has lasting value in its ability to reflect the human condition. The teaching of medical informatics, an intersection of technology and knowledge, is also most relevant when it transcends the operation of databases and systems. Librarians can teach students to understand, research, and utilize information beyond specific technologies. METHODS: A survey of twenty-six informatics programs was conducted during 2002, with specific emphasis on the role of the library service. RESULTS: The survey demonstrated that librarians currently do have a central role in informatics instruction, and that library-focused skills form a significant part of the curriculum in many of those programs. In addition, librarians have creative opportunities to enhance their involvement in informatics training. As a sample program in the study, the development of the informatics course at the Massachusetts College of Pharmacy and Health Sciences is included. CONCLUSIONS: Medical informatics training is a wonderful opportunity for librarians to collaborate with professionals from the sciences and other information disciplines. Librarians' unique combination of human research and technology skills provides a valuable contribution to any program.  相似文献   
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The author, a professor at the University of Toronto, touches briefly on the extensive and rich archival literature that supports the teaching of macroappraisal, but notes that this is not the only educational material she offers her students when teaching appraisal theory. She discusses the usefulness to archivists of literature from the fields of ethnography, organizational knowing, records in history, personal documentary behaviour, memory, and communications, noting that the use of texts from these fields can encourage students to reflect on their own presumptions and to develop a taste for the wide reading and research that must support appraisal.  相似文献   
7.
Word embeddings and convolutional neural networks (CNN) have attracted extensive attention in various classification tasks for Twitter, e.g. sentiment classification. However, the effect of the configuration used to generate the word embeddings on the classification performance has not been studied in the existing literature. In this paper, using a Twitter election classification task that aims to detect election-related tweets, we investigate the impact of the background dataset used to train the embedding models, as well as the parameters of the word embedding training process, namely the context window size, the dimensionality and the number of negative samples, on the attained classification performance. By comparing the classification results of word embedding models that have been trained using different background corpora (e.g. Wikipedia articles and Twitter microposts), we show that the background data should align with the Twitter classification dataset both in data type and time period to achieve significantly better performance compared to baselines such as SVM with TF-IDF. Moreover, by evaluating the results of word embedding models trained using various context window sizes and dimensionalities, we find that large context window and dimension sizes are preferable to improve the performance. However, the number of negative samples parameter does not significantly affect the performance of the CNN classifiers. Our experimental results also show that choosing the correct word embedding model for use with CNN leads to statistically significant improvements over various baselines such as random, SVM with TF-IDF and SVM with word embeddings. Finally, for out-of-vocabulary (OOV) words that are not available in the learned word embedding models, we show that a simple OOV strategy to randomly initialise the OOV words without any prior knowledge is sufficient to attain a good classification performance among the current OOV strategies (e.g. a random initialisation using statistics of the pre-trained word embedding models).  相似文献   
8.
ABSTRACT

This article explores the experiences of a group of established academic staff in New Zealand and the UK, as they undertake a doctorate in their home institutions. Our interest is in how individuals negotiate this dual status from a cultural-historical activity theory (CHAT) stance that explores how rules, tools, community and divisions of labour, and interacting activity systems, shape doctoral experiences. The focus in this article, having analysed their detailed narrative accounts, is on how academics experience three interdependent activity systems: those surrounding the thesis, the institutional context, and the home-life spheres. Issues related to time, workload and supervision issues, variability in collegial support and impact on personal priorities and time emerged. There is a range of particularities – from easy access to resources/supervisors to inflexible institutional regulations – applicable to this group of doctoral candidates. Negotiating life as an academic with concurrent doctoral candidature provides positive outcomes in terms of teaching, research confidence and general personal and professional development. However, a range of difficulties can also be encountered, particularly in relation to personal and professional relationships, and workload management.  相似文献   
9.
The release of the Old World Drought Atlas (OWDA) in November 2015 provides historians with an unprecedented glimpse into the climate of the medieval world. Through the careful examination of tree-ring data provided by the OWDA, historians can better gauge how the environment affected the course of medieval Mediterranean history, particularly in times and places where textual data is sparse, such as North Africa. The case studies of the Norman conquest of the coast of Ifrīqiyya in the 1140s and the invasion by the Banū Hilāl in the mid-eleventh century show the utility of the OWDA for gaining a better understanding the medieval Mediterranean. In particular, OWDA data shows that the arrival of the Banū Hilāl into Ifrīqiyya coincided with a period of extended drought that is not documented in the written sources and suggests that increased competition for scarce resources was instrumental to their entrance into the region.  相似文献   
10.
Abstract

Maternal dietary habits influence maternal and foetal health, representing a pathway for intervention to maximise pregnancy outcomes. Advice on energy intake is provided on a trimester basis, with no additional calories required in the first trimester and an additional 340?kcal?d?1 and 452?kcal?d?1 needed for the second and third trimesters. Energy intake depends on pre-gravid body mass index (BMI); underweight women are recommended an increase of 150, 200 and 300?kcal?d?1 during the first, second and third trimester, normal weight women an increase of 0, 350 and 500?kcal?d?1 and obese women an increase of 0, 450 and 350?kcal?day?1. The recommendations for carbohydrate and protein intake are 175?g?d?1 and 0.88–1.1?g?kgBM?d?1, with no change to fat intake. The number of pre-gravid obese women is rising; therefore, we need to regulate weight in women of childbearing age and limit gestational weight gain to within the recommended ranges [overweight women 6.8–11.3?kg and obese women 5.0–9.1?kg]. This can be achieved using nutritional interventions, as dietary changes have been shown to help with gestational weight management. As pregnancy has been identified as a risk factor for the development of obesity, normal weight women should gain 11.5–16.0?kg during pregnancy. While some research has shown that dietary interventions help to regulate gestational weight gain and promote postpartum weight loss to some extent, future research is needed to provide safe and effective guidelines to maximise these effects, while benefitting maternal and foetal health.  相似文献   
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