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Positional cloning of the allorecognition gene alr1 in the cnidarian Hydractinia symbiolongicarpus "Rosa, Sabrina F.P. 08 March 2010 (has links)
Allorecognition, defined as the ability to discriminate between self and non-self, is ubiquitous to colonial metazoans and widespread in aclonal taxa. Invertebrate allorecognition phenomena are of broad interest and have long captured the attention of geneticists by virtue of the allotypic diversity they display, marine ecologists by virtue of their control of effector mechanisms determining the outcome of intraspecific competition, evolutionary biologists by virtue of their regulation of the level at which selection acts, and immunologists by virtue of their resemblance to the allogeneic interactions that characterize pregnancy and transplantation in vertebrates. Diverse histocompatibility modes have been described in the jawed vertebrates, protochordates, and cnidarians, which are to date the only three taxa for which a genetic model to study allorecognition has been developed. Outside of the MHC-based histocompatibility of vertebrates, allorecognition determinants have been recognized in only two invertebrates. In the tunicate Botryllus, two genes involved in the histocompatibility response were characterized, FuHc and fester. In Hydractinia, the loci controlling allorecognition, alr1 and alr2, were mapped to a single chromosomal region, the allorecognition complex, and alr2 was recently identified as a polymorphic immunoglobulin superfamily (IgSF) receptor. In this study, the identification of the second Hydractinia allodeterminant, alr1, was undertaken. Chapter I briefly reviews prominent allorecognition model organisms and details the phenomenon in the model organism, Hydractinia symbiolongicarpus studied here. Chapter II describes the isolation of a 300.8 kb alr1-containing chromosomal interval by positional cloning. The analysis of that interval for its gene content and the determination of a primary alr1 candidate, CDS4, are described in Chapter III. Chapter III also reveals the existence of a complex of IgSF-like genes, to which belongs CDS4. CDS4, a novel polymorphic IgSF receptor that encodes a type I transmembrane protein with two hypervariable immunoglobulin-like extracellular domains, was confirmed to be the alr1 allodeterminant in Chapter IV, based on the investigation of natural polymorphism. CDS4 allele sequences were found to largely predict the outcome of allorecognition responses within and between laboratory lines and wild-type colonies, confirming the identity of CDS4 as the classically defined locus alr1.
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Adherence and Effectiveness of Positional Therapy for Obstructive Sleep Apnea SyndromeFridel, Keith January 2011 (has links)
The purpose of this investigation was to explore how adherence to a positional therapy intervention affected therapeutic outcome in participants with positional-related obstructive sleep apnea syndrome. Eighteen adult participants identified as having positional-related obstructive sleep apnea by an initial overnight polysomnography study were recruited. Participants were instructed to use a “tennis ball technique” positional device for three weeks at home and record their sleep habits and adherence before a final post-treatment polysomnography evaluation. A repeated measures MANOVA found significant effects of treatment between pre- and post-test on the objective polysomnography variables of Total Recording Time [F(1,17) = 5.21, p<.05, η²=.24], Total Sleep Time [F(1,17) = 8.59, p<.01, η²=.34], Sleep Efficiency [F(1,17) = 5.42, p<.05, η²=.24], Total REM sleep time [F(1,17) = 9.91, p<.01, η²=.37], and the Apnea- Hypopnea Index [F(1,17) = 14.28, p<.001, η²=.46]. Sleep onset latency was not statistically significant. There were significant effects of treatment on the subjective measures of the Functional Outcome of Sleep Quality [F(1,17) = 8.92, p<.01, η²=.35], Pittsburgh Sleep Quality Index [F(1,17) = 11.2, p<.01, η²=..39], Epworth Sleepiness Scale [F(1,17) = 6.69, p<.05, η²=.28], and the Brief Symptom Inventory [F(1,17) = 5.14, p<.05, η²=.23]. No significant interaction effects were found between treatment and adherence when participants were grouped post-hoc into an adherent or non-adherent categories based on their self-reported daily log data. In summary, the results of this study indicated that the positional device was efficacious for significantly improving both objective polysomnography variables and subjective variables of sleep. The results also indicated even partially adherent participants reported significant improvements in nighttime sleep quality and quality of life after the three week treatment period. Mixed Linear Modeling demonstrated that significant improvements in sleep quality, time to sleep onset, and total sleep time were not seen until the last weeks of treatment. This study found very acceptable adherence rates with this positional device design; all participants were able to utilize the therapeutic device on at least a portion of every night during the three-week intervention.
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Molecular analysis of the Ellis-van Creveld critical regionWoods, Kathryn Sage January 1999 (has links)
No description available.
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Organisational responses to the employability agenda in English universitiesGilworth, Robert January 2013 (has links)
Employability is highly topical in UK Higher Education. There is related literature debating the purpose of higher education, learning and skills, contextual social and economic issues and policy matters for the sector as a whole, but no published work on the ways in which universities organise themselves to deal with this particular issue. This study examines the organisational responses of universities to the issue of graduate employability at this pivotal time for English higher education, when the environment is linking employability to institutional success to an unprecedented degree. The study considers key contextual factors including the debate around the relationship between “the knowledge economy” and the demand for graduates, the ways in which success in employability is understood and measured, the impact of recession and the tension between student consumerism and partnership in an environment in which “consumer information” is linked directly by government to notions of return on personal investment and value for money as tuition fees increase. The key questions addressed are: how is the employability offer conceptualised, constructed, managed and measured and what choices about organisational configuration and capability are being made and acted upon? The study required detailed analysis of the relationships between institutional mission and top-level goals, declared strategy for delivery and delivery structures and the roles of key individuals and teams and so, this enquiry is based upon in-depth case studies of five universities, using data on graduate destinations, published statements and strategies and interviews with relevant post holders (with a particular focus on the role of the head of the professional career service). The case studies and analysis relate the organisational responses to the underlying driver of positional competition. The study uses the role and position of careers services as the starting point for attempting to understand the organisational responses in each case.
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Analysis of the positional accuracy of linear features.Lawford, Geoffrey John Unknown Date (has links) (PDF)
Although the positional accuracy of spatial data has long been of fundamental importance in GIS, it is still largely unknown for linear features. This is compromising the ability of GIS practitioners to undertake accurate geographic analysis and hindering GIS in fulfilling its potential as a credible and reliable tool. As early as 1987 the US National Center for Geographic Information and Analysis identified accuracy as one of the key elements of successful GIS implementation. Yet two decades later, while there is a large body of geodetic literature addressing the positional accuracy of point features, there is little research addressing the positional accuracy of linear features, and still no accepted accuracy model for linear features. It has not helped that national map and data accuracy standards continue to define accuracy only in terms of “well-defined points”. This research aims to address these shortcomings by exploring the effect on linear feature positional accuracy of feature type, complexity, segment length, vertex proximity and e-scale, that is, the scale of the paper map from which the data were originally captured or to which they are customised for output. / The research begins with a review of the development of map and data accuracy standards, and a review of existing research into the positional accuracy of linear features. A geographically sensible error model for linear features using point matching is then developed and a case study undertaken. Features of five types, at five e-scales, are selected from commonly used, well-regarded Australian topographic datasets, and tailored for use in the case study. Wavelet techniques are used to classify the case study features into sections based on their complexity. Then, using the error model, half a million offsets and summary statistics are generated that shed light on the relationships between positional accuracy and e-scale, feature type, complexity, segment length, and vertex proximity. Finally, auto-regressive time series modelling and moving block bootstrap analysis are used to correct the summary statistics for correlation. / The main findings are as follows. First, metadata for the tested datasets significantly underestimates the positional accuracy of the data. Second, positional accuracy varies with e-scale but not, as might be expected, in a linear fashion. Third, positional accuracy varies with feature type, but not as the rules of generalisation suggest. Fourth, complex features lose accuracy faster than less complex features as e-scale is reduced. Fifth, the more complex a real-world feature, the worse its positional accuracy when mapped. Finally, accuracy mid-segment is greater than accuracy end-segment.
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Terrain based routing protocol for sparse ad-hoc intermittent network (TRAIN)Dawra, Gaurav. January 2005 (has links) (PDF)
Thesis (M. S.)--Montana State University--Bozeman, 2005. / Typescript. Chairperson, Graduate Committee: Brendan Mumey. Includes bibliographical references (leaves 70-73).
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The semantics and grammar of positional verbs in Gurenε : a typological perspectiveAtintono, Samuel Awinkene January 2013 (has links)
This thesis provides a detailed study of the semantics, grammar, and pragmatics of positional verbs from a typological perspective in Gurenɛ, a Gur (Niger-Congo) language spoken in Northern Ghana. The study documents and describes Gurenɛ positional verbs in detail focusing on a set of over thirty contrastive positional verbs using a documentary corpus of natural and stimuli-based elicited data. “Positional verbs” is used in this study as a cover term that refers to a class of verbs that semantically encode the static assumed body posture or position of animate entities (humans and animals) or the static location of inanimates (objects) in space. The study discusses the Gurenɛ data in the context of recent cross-linguistic studies on posture, positional and locative verbs (Newman 2002a; Levinson & Wilkins 2006a, Ameka & Levinson 2007a) which suggest that some languages employ verbs rather than adpositions to describe locations. It compares the Gurenɛ data to these typological studies to establish the similarities and the differences of the semantics of these verbs. Like other languages observed in these studies, the use of verbs in the Gurenɛ locative construction is obligatory and the verbs constitute the main linguistic means that the speakers use for locative descriptions. The thesis further explores in part, the basic locative construction (BLC) typology of Levinson & Wilkins (2006a) and Ameka & Levinson (2007a). The BLC typology is concerned with the use of verbs in languages to express spatial locative information with the claim that languages can be classified into four main types according to the number and types of verbs used in their BLC; Type 0 (no verb), Type I (one locative verb or a copula), Type II (three to seven postural verbs), and Type III (seven to +100 positional verbs). In Gurenɛ over thirty verbs are identified that can be used in its BLC. As a result, Gurenɛ is classified as a Type III language. Like any other Type III language, as predicted by the BLC typology, the language uses its verbs to describe a wide range of precise semantic notions involving different locative relations between the Figure and the Ground such as body position, elevation, attachment, containment, distribution, and relative distance. The findings among others suggest that in a locative scene where the Ground is elevated more specific verbs of elevation with very precise meanings associated with the Figure’s properties which include stable base support, shape, and position are used. Additionally, the Ground elevation disregards the actual posture of the Figure. Thus, if a speaker observes a Figure on the ground (earth or floor level) the actual posture verb is used, but if the Figure is on an elevated Ground (e.g., a tabletop, a rooftop) the actual posture is disregarded. This “elevation” phenomenon has not been fully discussed in the cross-linguistic studies of the positional and locative verbs in the semantic literature. The Gurenɛ data make a contribution toward clarification of the range and type of distinctions to be accounted for in the semantic typology of the use of these verbs in locative descriptions.
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Action of the Cubitus Interruptus‐wallace Mutant in Drosophila Melanogaster: A Study of Leg Morphology on Mosaic and Haplo‐4 FliesBenner, D. B. 01 January 1987 (has links)
The fourth chromosome mutant cubitus interruptus‐Wallace(ciW) produces leg, wing, and body bristle aberrations. The effect on the wing is similar to that produced by cubitus interruptus‐dominant (ciD) which also has an influence on larval segmentation indicating that it has a regulatory function. Leg morphology of haplo‐4, ciW, and mosaic haplo‐4:diplo‐4, ci/ci+ flies was examined in an attempt to distinguish between a structural and a regulatory function by ciW. Aberrations recovered include failure of segment elongation, intersegmental gaps, duplication of bristles, and segments that are shorter than normal and of greater than normal diameter. Many of these effects are localized, suggesting that ciW may act to maintain cell positional reference. Increased local cell proliferation appears to be one manifestation of loss of the normal function.
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A PC based expert system for positional tolerance allocationMehta, Anuj January 1994 (has links)
No description available.
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Quality Assessment of Spatial Data: Positional Uncertainties of the National Shoreline Data of SwedenHast, Isak January 2014 (has links)
This study investigates on the planimetric (x, y) positional accuracy of the National Shoreline (NSL) data, produced in collaboration between the Swedish mapping agency Lantmäteriet and the Swedish Maritime Administration (SMA). Due to the compound nature of shorelines, such data is afflicted by substantial positional uncertainties. In contrast, the positional accuracy requirements of NSL data are high. An apparent problem is that Lantmäteriet do not measure the positional accuracy of NSL in accordance to the NSL data product specification. In addition, currently, there is little understanding of the latent positional changes of shorelines affected by the component of time, in direct influence of the accuracy of NSL. Therefore, in accordance to the two specific aims of this study, first, an accuracy assessment technique is applied so that to measure the positional accuracy of NSL. Second, positional time changes of NSL are analysed. This study provides with an overview of potential problems and future prospects of NSL, which can be used by Lantmäteriet to improve the quality assurance of the data. Two line-based NSL data sets within the NSL classified regions of Sweden are selected. Positional uncertainties of the selected NSL areas are investigated using two distinctive methodologies. First, an accuracy assessment method is applied and accuracy metrics by the root-means-square error (RMSE) are derived. The accuracy metrics are checked toward specification and standard accuracy tolerances. Results of the assessment by the calculated RMSE metrics in comparison to tolerances indicate on an approved accuracy of tested data. Second, positional changes of NSL data are measured using a proposed space-time analysis technique. The results of the analysis reveal significant discrepancies between the two areas investigated, indicating that one of the test areas are influenced by much greater positional changes over time. The accuracy assessment method used in this study has a number of apparent constraints. One manifested restriction is the potential presence of bias in the derived accuracy metrics. In mind of current restrictions, the method to be preferred in assessment of the positional accuracy of NSL is a visual inspection towards aerial photographs. In regard of the result of the space-time analysis, one important conclusion can be made. Time-dependent positional discrepancies between the two areas investigated, indicate that Swedish coastlines are affected by divergent degrees of positional changes over time. Therefore, Lantmäteriet should consider updating NSL data at different time phases dependent on the prevailing regional changes so that to assure the currently specified positional accuracy of the entire data structure of NSL.
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