The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Gareth J. Fraser - One of the best experts on this subject based on the ideXlab platform.
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Conserved gene signalling and a derived patterning mechanism underlie the development of avian footpad scales
EvoDevo, 2019Co-Authors: Rory L. Cooper, Victoria J. Lloyd, Nicolas Di-poï, Alexander G. Fletcher, Paul M. Barrett, Gareth J. FraserAbstract:Background Vertebrates possess a diverse range of integumentary epithelial appendages, including scales, feathers and hair. These structures share extensive early developmental homology, as they mostly originate from a conserved anatomical placode. In the context of avian epithelial appendages, feathers and scutate scales are known to develop from an anatomical placode. However, our understanding of avian reticulate (footpad) scale development remains unclear. Results Here, we demonstrate that reticulate scales develop from restricted circular Domains of thickened epithelium, with localised conserved gene expression in both the epithelium and underlying mesenchyme. These Domains constitute either anatomical placodes, or circular initiatory fields (comparable to the avian feather tract). Subsequent patterning of reticulate scales is consistent with reaction–diffusion (RD) simulation, whereby this Primary Domain subdivides into smaller secondary units, which produce individual scales. In contrast, the footpad scales of a squamate model (the bearded dragon, Pogona vitticeps ) develop synchronously across the ventral footpad surface. Conclusions Widely conserved gene signalling underlies the initial development of avian reticulate scales. However, their subsequent patterning is distinct from the footpad scale patterning of a squamate model, and the feather and scutate scale patterning of birds. Therefore, we suggest reticulate scales are a comparatively derived epithelial appendage, patterned through a modified RD system.
Paul G Shekelle - One of the best experts on this subject based on the ideXlab platform.
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systematic review impact of health information technology on quality efficiency and costs of medical care
Annals of Internal Medicine, 2006Co-Authors: Basit Chaudhry, Jerome K Wang, Shinyi Wu, Margaret Maglione, Walter Mojica, Elizabeth Roth, Sally C Morton, Paul G ShekelleAbstract:BACKGROUND: Experts consider health information technology key to improving efficiency and quality of health care. PURPOSE: To systematically review evidence on the effect of health information technology on quality, efficiency, and costs of health care. DATA SOURCES: The authors systematically searched the English-language literature indexed in MEDLINE (1995 to January 2004), the Cochrane Central Register of Controlled Trials, the Cochrane Database of Abstracts of Reviews of Effects, and the Periodical Abstracts Database. We also added studies identified by experts up to April 2005. STUDY SELECTION: Descriptive and comparative studies and systematic reviews of health information technology. DATA EXTRACTION: Two reviewers independently extracted information on system capabilities, design, effects on quality, system acquisition, implementation context, and costs. DATA SYNTHESIS: 257 studies met the inclusion criteria. Most studies addressed decision support systems or electronic health records. Approximately 25% of the studies were from 4 academic institutions that implemented internally developed systems; only 9 studies evaluated multifunctional, commercially developed systems. Three major benefits on quality were demonstrated: increased adherence to guideline-based care, enhanced surveillance and monitoring, and decreased medication errors. The Primary Domain of improvement was preventive health. The major efficiency benefit shown was decreased utilization of care. Data on another efficiency measure, time utilization, were mixed. Empirical cost data were limited. LIMITATIONS: Available quantitative research was limited and was done by a small number of institutions. Systems were heterogeneous and sometimes incompletely described. Available financial and contextual data were limited. CONCLUSIONS: Four benchmark institutions have demonstrated the efficacy of health information technologies in improving quality and efficiency. Whether and how other institutions can achieve similar benefits, and at what costs, are unclear.
Rory L. Cooper - One of the best experts on this subject based on the ideXlab platform.
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Conserved gene signalling and a derived patterning mechanism underlie the development of avian footpad scales
EvoDevo, 2019Co-Authors: Rory L. Cooper, Victoria J. Lloyd, Nicolas Di-poï, Alexander G. Fletcher, Paul M. Barrett, Gareth J. FraserAbstract:Background Vertebrates possess a diverse range of integumentary epithelial appendages, including scales, feathers and hair. These structures share extensive early developmental homology, as they mostly originate from a conserved anatomical placode. In the context of avian epithelial appendages, feathers and scutate scales are known to develop from an anatomical placode. However, our understanding of avian reticulate (footpad) scale development remains unclear. Results Here, we demonstrate that reticulate scales develop from restricted circular Domains of thickened epithelium, with localised conserved gene expression in both the epithelium and underlying mesenchyme. These Domains constitute either anatomical placodes, or circular initiatory fields (comparable to the avian feather tract). Subsequent patterning of reticulate scales is consistent with reaction–diffusion (RD) simulation, whereby this Primary Domain subdivides into smaller secondary units, which produce individual scales. In contrast, the footpad scales of a squamate model (the bearded dragon, Pogona vitticeps ) develop synchronously across the ventral footpad surface. Conclusions Widely conserved gene signalling underlies the initial development of avian reticulate scales. However, their subsequent patterning is distinct from the footpad scale patterning of a squamate model, and the feather and scutate scale patterning of birds. Therefore, we suggest reticulate scales are a comparatively derived epithelial appendage, patterned through a modified RD system.
Pamela M Perniss - One of the best experts on this subject based on the ideXlab platform.
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does space structure spatial language linguistic encoding of space in sign languages
Cognitive Science, 2011Co-Authors: Pamela M Perniss, I E P Zwitserlood, Asli OzyurekAbstract:Does Space Structure Spatial Language? Linguistic Encoding of Space in Sign Languages Pamela Perniss (pamela.perniss@mpi.nl) Inge Zwitserlood (inge.zwitserlood@mpi.nl) Asli Ozyurek (asli.ozyurek@mpi.nl) Radboud University Nijmegen & Max Planck Institute for Psycholinguistics PO Box 310, 6500 AH Nijmegen, Netherlands space. The spatial relationship between the signer’s hands represents the spatial relationship between the referents, whereby the handshapes are iconic with certain features of the referents (e.g. the inverted cupped hand to represent the bulk of a house). In contrast, there is no resemblance, or iconicity, between the actual scene and the linguistic form of a spoken language locative expression, as e.g. the English expression There is a bicycle next to the house. Abstract Spatial language in signed language is assumed to be shaped by affordances of the visual-spatial modality – where the use of the hands and space allow the mapping of spatial relationships in an iconic, analogue way – and thus to be similar across sign languages. In this study, we test assumptions regarding the modality-driven similarity of spatial language by comparing locative expressions (e.g., cup is on the table) in two unrelated sign languages, TID (Turk Isaret Dili, Turkish Sign Language) and DGS (Deutsche Gebardensprache, German Sign Language) in a communicative, discourse context. Our results show that each sign language conventionalizes the structure of locative expressions in different ways, going beyond iconic and analogue representations, suggesting that the use of space to represent space does not uniformly and predictably drive spatial language in the visual-spatial modality. These results are important for our understanding of how language modality shapes the structure of language. HOUSE loc here BICYCLE loc next-to-house Figure 1. Example of an ASL (American Sign Language) locative expression depicting the spatial relationship of a bicycle next to a house (Emmorey, 2002). The expression contains the lexical signs for house (still 1) and bicycle (still 3), each followed by a locative predicate localizing the referent in space. Keywords: iconicity; language modality; spatial language; locative expression; sign language Introduction Despite the difference in modality of expression, signed (visual-spatial) and spoken (vocal-aural) languages similarly conform to principles of grammatical structure and linguistic form (Klima & Bellugi, 1979; Liddell, 1980; Padden, 1983; Stokoe, 1960; Supalla, 1986). However, in signed language, the use of the hands as Primary articulators within a visible spatial medium for expression (i.e. the space around the body) has special consequences for the expression of visual-spatial information (e.g. of referent size/shape, location, or motion). Spatial language, such as locative expressions, is a Primary Domain in which modality affects the structure of representation. Locative expressions in both signed and spoken language are characterized by linguistic encoding of entities and the spatial relationship between them (cf. Talmy, 1985). However, sign language locative expressions differ radically from those in spoken language in affording a visual similarity (or iconicity) with the real-world scenes being represented. For example, a signed expression of the spatial relationship between a house and a bicycle is clearly iconic of the scene itself. In the example from American Sign Language (ASL) in Figure 1, the signer depicts a bicycle as being located beside a house by placing her hands (her left hand representing the house in still 2; her right hand representing the bicycle in still 4) next to each other in sign In general, spoken languages exhibit a wide range of cross- linguistic variation in the encoding of spatial relationships in locative expressions, both in the devices used and in their morphosyntactic arrangement (Grinevald, 2006; Levinson & Wilkins, 2006). For example, spoken language locative expressions exhibit the use of adpositions, like the spatial prepositions used in English or the case-marking postpositions used in Turkish, or different types of locative or postural verbs (as in Ewe (Ghana) or Tzeltal (Mexico)). Such variation is not expected in signed languages, however. Instead, signed languages are assumed to be structurally homogenous in the expression of spatial relationships. The affordances of the visual-spatial modality for iconic, analogue spatial representation are assumed to be the Primary force in shaping spatial expression, thus creating fundamental similarities in spatial language across different sign languages (e.g. Aronoff, Meir, Padden & Sandler, 2003; Emmorey, 2002). A consequence of this assumption of similarity, rooted in the notion that signers will exploit the iconic affordances of the modality where possible, has been a dearth of empirical investigation in this Domain. Where the encoding of spatial relationships is mentioned in the literature, its iconic character is stated as fact, and conforms to the underlying assumption that spatial relationships will be represented in an iconic, analogue way,
Basit Chaudhry - One of the best experts on this subject based on the ideXlab platform.
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systematic review impact of health information technology on quality efficiency and costs of medical care
Annals of Internal Medicine, 2006Co-Authors: Basit Chaudhry, Jerome K Wang, Shinyi Wu, Margaret Maglione, Walter Mojica, Elizabeth Roth, Sally C Morton, Paul G ShekelleAbstract:BACKGROUND: Experts consider health information technology key to improving efficiency and quality of health care. PURPOSE: To systematically review evidence on the effect of health information technology on quality, efficiency, and costs of health care. DATA SOURCES: The authors systematically searched the English-language literature indexed in MEDLINE (1995 to January 2004), the Cochrane Central Register of Controlled Trials, the Cochrane Database of Abstracts of Reviews of Effects, and the Periodical Abstracts Database. We also added studies identified by experts up to April 2005. STUDY SELECTION: Descriptive and comparative studies and systematic reviews of health information technology. DATA EXTRACTION: Two reviewers independently extracted information on system capabilities, design, effects on quality, system acquisition, implementation context, and costs. DATA SYNTHESIS: 257 studies met the inclusion criteria. Most studies addressed decision support systems or electronic health records. Approximately 25% of the studies were from 4 academic institutions that implemented internally developed systems; only 9 studies evaluated multifunctional, commercially developed systems. Three major benefits on quality were demonstrated: increased adherence to guideline-based care, enhanced surveillance and monitoring, and decreased medication errors. The Primary Domain of improvement was preventive health. The major efficiency benefit shown was decreased utilization of care. Data on another efficiency measure, time utilization, were mixed. Empirical cost data were limited. LIMITATIONS: Available quantitative research was limited and was done by a small number of institutions. Systems were heterogeneous and sometimes incompletely described. Available financial and contextual data were limited. CONCLUSIONS: Four benchmark institutions have demonstrated the efficacy of health information technologies in improving quality and efficiency. Whether and how other institutions can achieve similar benefits, and at what costs, are unclear.