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31.
How do public libraries develop their collections of high-demand materials for the “I want it now” generation? Ten public libraries’ holdings of fiction and nonfiction bestseller titles were observed over a four-week period. The number of copies rose fairly consistently, with the five fiction titles having roughly about twice the number of copies as the five nonfiction titles. The ratio of holds to copies averaged 2.7:1 and ranged from 0.8:1 to 6.5:1. Demand for e-books was consistently higher than the number of copies available, averaging more than 4:1 across all libraries.  相似文献   
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Human Coronaviruses (hCoVs) belongs to the enormous and dissimilar family of positive-sense, non-segmented, single-stranded RNA viruses. The RNA viruses are prone to high rates of mutational recombination resulting in emergence of evolutionary variant to alter various features including transmissibility and severity. The evolutionary changes affect the immune escape and reduce effectiveness of diagnostic and therapeutic measures by becoming undetectable by the currently available diagnostics and refractory to therapeutics and vaccines. Whole genome sequencing studies from various countries have adequately reported mosaic recombination between different lineage strain of SARS-CoV-2 whereby RNA dependent RNA polymerase (RdRp) gene reconnects with a homologous RNA strand at diverse position. This all lead to evolutionary emergence of new variant/ lineage as evident with the emergence of XBB in India at the time of writing this review. The continuous periodical genomic surveillance is utmost required for understanding the various lineages involved in recombination to emerge into hybrid variant. This may further help in assessing virus transmission dynamics, virulence and severity factor to help health authorities take appropriate timely action for prevention and control of any future COVID-19 outbreak.  相似文献   
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In this study 149 kindergarten children were assessed for knowledge of letter names and letter sounds, phonological awareness, and cognitive abilities. Through this it examined child and letter characteristics influencing the acquisition of alphabetic knowledge in a naturalistic context, the relationship between letter-sound knowledge and letter-name knowledge, and the prediction of Grade 1 phonological awareness and word identification from these variables. Knowledge of letter sounds was better for vowels and for letters with consonant–vowel names than for those with vowel–consonant names or names bearing little relationship to their sounds. However, there were anomalies within each category reflecting characteristics of the individual letters. Structural equation modelling showed that cognitive ability, comprising receptive vocabulary, non-verbal reasoning, rapid automatized naming of colours, and phonological memory significantly contributed to alphabetic knowledge and phonological awareness. In turn, letter-name knowledge but not phonological awareness predicted letter-sound knowledge and subsequent reading skill.This research was supported by a grant from the Social Sciences and Humanities Research Council of Canada to the first author. Thank you is extended to the participating schools and children and to Ian Newby-Clark for his orientation to AMOS. Michelle Bell, Shelly Moretti and Jodi Page have since graduated from the University of Guelph  相似文献   
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Searches by end users and intermediaries on the online PDQ (Physician Data Query) cancer information system were observed. With the National Library of Medicine (NLM) menu-based interface, end users (physicians) averaged fewer steps per question, while with the BRS command-drive interface, intermediaries appeared to be more efficient. Cancer Information Service (CIS) searchers, who have more PDQ experience than end users or intermediaries, made greater use of command stacking to anticipate menu selections. Retrieval was more complete in the NLM system, where both the menus and predefined print formats assisted the searchers.  相似文献   
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