2,221 research outputs found

    Reproduction in selected New Zealand native ferns and their suitability for revegetation : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Plant Biology at Massey University, Palmerston North, New Zealand

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    The potential to use New Zealand native ferns for revegetation was assessed in laboratory , nursery and field experiments. Laboratory experiments indicated that the three native fern species. Blechnum novae-zelandiae. Cyathea medullaris and Dicksonia squarossa, had different maximum levels of spore germination. These differences also varied in response to seasonal changes in the environment. The effect of three soil conditioners on the germination of the same three species was minimal Gametophytes appeared to be tolerant of low levels of maceration, as they were able to continue to grow and develop normally. Additional laboratory experiments indicated that B. novae-zelandiae employs a mixed mating system, which utilizes an "antheridiogen" signal. The development of fern spores, laboratory propagated gametophytes and segmented rhizomes, was assessed in the nursery. Each experiment was applied with a hvdroseeding mix of paper fibre, tackifier. fertilizer and water Spore of B. novae-zelandiae. C. medullaris and D. squarossa failed to produce any long-lived gametophytes The survival of laboratory propagated gametophytes of B. novae-zelandiae. B. discolor and B. colensoi was low. However, a large proportion of surviving B. novae-zelandiae gametophytes produced sporophytes. B. novae-zelandiae rhizome segments produced healthy young ferns within 3 months of application. Field experiments were conducted on a sandstone/loess bank. 5 km east of Palmerston North. Aspects of the substrate were analysed including. pH. N, P and organic matter. The results indicated that the bank had a high soil pH, was deficient in several macronutrients and had no organic matter. Hydroseeding was applied using spore of the species B novae-zelandiae, C. medullaris and D. squarossa Hydroseeded spore failed to produce any visible gametophytes Rhizome experiments using B. novae-zelandiae and Microsorum pustulatum were also established. Low water availability resulted in poor rhizome establishment. The results suggest that there is great potential for utilizing native ferns in revegetation. Blechnum novae-zelandiae is the best species for revegetation in accordance to the results. Propagation via rhizome segmentation and gametophyte hydroseeding appear to be the most successful methods for establishing native ferns. This TIF project was carried out in conjunction with Rural Supply Technologies. Manaaki Whenua Landcare Research. Massey University and FoRST New Zealand

    A STUDY OF REMOTELY SENSED AEROSOL PROPERTIES FROM GROUND-BASED SUN AND SKY SCANNING RADIOMETERS

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    Aerosol particles impact human health by degrading air quality and affect climate by heating or cooling the atmosphere. The Indo-Gangetic Plain (IGP) of Northern India, one of the most populous regions in the world, produces and is impacted by a variety of aerosols including pollution, smoke, dust, and mixtures of them. The NASA Aerosol Robotic Network (AERONET) mesoscale distribution of Sun and sky-pointing instruments in India was established to measure aerosol characteristics at sites across the IGP and around Kanpur, India, a large urban and industrial center in the IGP, during the 2008 pre-monsoon (April-June). This study focused on detecting spatial and temporal variability of aerosols, validating satellite retrievals, and classifying the dominant aerosol mixing states and origins. The Kanpur region typically experiences high aerosol loading due to pollution and smoke during the winter and high aerosol loading due to the addition of dust to the pollution and smoke mixture during the pre-monsoon. Aerosol emissions in Kanpur likely contribute up to 20% of the aerosol loading during the pre-monsoon over the IGP. Aerosol absorption also increases significantly downwind of Kanpur indicating the possibility of the black carbon emissions from aerosol sources such as coal-fired power plants and brick kilns. Aerosol retrievals from satellite show a high bias when compared to the mesoscale distributed instruments around Kanpur during the pre-monsoon with few high quality retrievals due to imperfect aerosol type and land surface characteristic assumptions. Aerosol type classification using the aerosol absorption, size, and shape properties can identify dominant aerosol mixing states of absorbing dust and black carbon particles. Using 19 long-term AERONET sites near various aerosol source regions (Dust, Mixed, Urban/Industrial, and Biomass Burning), aerosol absorption property statistics are expanded upon and show significant differences when compared to previous work. The sensitivity of absorption properties is evaluated and quantified with respect to aerosol retrieval uncertainty. Using clustering analysis, aerosol absorption and size relationships provide a simple method to classify aerosol mixing states and origins and potentially improve aerosol retrievals from ground-based and satellite-based instrumentation

    Transient neurological symptoms in the older population:report of a prospective cohort study--the Medical Research Council Cognitive Function and Ageing Study (CFAS)

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    Transient ischaemic attack (TIA) is a recognised risk factor for stroke in the older population requiring timely assessment and treatment by a specialist. The need for such TIA services is driven by the epidemiology of transient neurological symptoms, which may not be caused by TIA. We report prevalence and incidence of transient neurological symptoms in a large UK cohort study of older people

    Sub-shot-noise shadow sensing with quantum correlations

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    The quantised nature of the electromagnetic field sets the classical limit to the sensitivity of position measurements. However, techniques based on the properties of quantum states can be exploited to accurately measure the relative displacement of a physical object beyond this classical limit. In this work, we use a simple scheme based on the split-detection of quantum correlations to measure the position of a shadow at the single-photon light level, with a precision that exceeds the shot-noise limit. This result is obtained by analysing the correlated signals of bi-photon pairs, created in parametric downconversion and detected by an electron multiplying CCD (EMCCD) camera employed as a split-detector. By comparing the measured statistics of spatially anticorrelated and uncorrelated photons we were able to observe a significant noise reduction corresponding to an improvement in position sensitivity of up to 17% (0.8dB). Our straightforward approach to sub-shot-noise position measurement is compatible with conventional shadow-sensing techniques based on the split-detection of light-fields, and yields an improvement that scales favourably with the detector’s quantum efficiency

    Characterization of transposon insertion mutants in desulfovibrio vulgaris hilderborough by sequencing genomic DNA [abstract]

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    Abstract only availableTn5 transposon mutagenesis occurs by a mechanism in which a segment of DNA (transposon) encoded in a plasmid is inserted into genomic DNA (the target) by a conservative (cut-and-paste) mechanism. When the insertion position is in a coding sequence or regulatory region of DNA, the insertion results in a mutation. The plasmid pRL27 encodes a mini-Tn5 transposon, Tn5 transposase, and kanamycin resistance, (Metcalf, William W. et al, 2002 Arch Microbiol 178 :193-201) and was used to transform Desulfovibrio vulgaris Hildenborough by electroporation. Transposon insertion mutants were identified by their ability to grow in the presence of kanamycin. To identify the insertion sites of the transposons, in theory one should be able to sequence from the transposon into chromosomal DNA and identify the mutation site by comparison with the known genome. Unlike sequencing of plasmid DNA or PCR products, direct genomic sequencing has a limited success rate. Direct genomic sequencing is sensitive to DNA quality, interference of secondary DNA structures, salt concentration, and the availability of primer binding sites. Because of these difficulties, in our attempts to identify insertion sites of mini-Tn5, we examined template DNA quality as well as modifying sequencing reaction conditions. Our objective is to develop an effective, reliable method for sequencing genomic DNA to identify where transposon insertion sites have occurred in each mutant.Department of Energy Genomics: Genomes to Life Progra

    Novel Prostate Cancer Biomarkers Derived from Autoantibody Signatures

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    AbstractBACKGROUND: Due to the low specificity of the prostate-specific antigen (PSA) assay and a high false positive rate, a large number of prostate cancer (PCA) biopsies are performed unnecessarily. Consequently, there is a need for new biomarkers that can identify PCA at any stage of progression while limiting the number of false positives. The use of autoantibody signature–developed biomarkers has proven to be an effective method to solve this problem. RESULTS: Using T7 phage–peptide detection, we identified a panel of eight biomarkers for PCA on a training set. The estimated receiver-operating characteristic (ROC) curve had an area under the ROC curve of 0.69 when applied to the validation set. Spearman correlations were high, within 0.7 to 0.9, indicating that the biomarkers have a degree of inter-relatedness. The identified biomarkers play a role in processes such as androgen response regulation and cellular structural integrity and are proteins that are thought to play a role in prostate tumorigenesis. CONCLUSIONS: Autoantibodies against PCA can be developed as biomarkers for detecting PCA. The scores from the algorithm developed here can be used to indicate a relative high or low risk of PCA, particularly for patients with intermediate (4.0 to 10 ng/ml) PSA levels. Since most commercially available assays test for PSA or have a PSA component, this novel approach has the potential to improve diagnosis of PCA using a biologic measure independent of PSA

    Design by searching : a system for creating and evaluating complex architectural assemblies

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    Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.Includes bibliographical references (p. 168-172).This work investigates a prototypical Web-based search system designed to enable architects and/or developers to engage and educate residential consumers in a new way: as co-designers. The key motivation is to develop software tools that support a feasible industrial process while providing home consumers with a way to conceive of and design spaces, as an alternative to the standardized commodity solutions that are currently available. The basic mode of operation for this work is to combine the structure of the modern computational search with emerging building modeling technologies as a foundation for Web-based participative design tools. Object-oriented component representations have been utilized to build a solution space that can be searched directly, without indexing. Additionally, conceptual query interfaces have been designed and evaluated through interviews with volunteer users. 'The component-based solutions and conceptual queries were then incorporated into a prototype of an architectural search tool which was analyzed to measure its effectiveness.by Matthew Giles Phillips.S.M

    Ogilvie's syndrome with caecal perforation after Caesarean section: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Ogilvie's syndrome describes the phenomenon of an acute colonic pseudo-obstruction without a mechanical cause. It is rare but has been reported to occur after Caesarean section. It can lead to bowel perforation or ischaemia.</p> <p>Case presentation</p> <p>A healthy, 28-year-old Caucasian woman presented 2 weeks past her expected date of delivery for her first pregnancy. She underwent an uncomplicated elective Caesarean section but developed abdominal pain and bloating postoperatively and was subsequently diagnosed with acute colonic pseudo-obstruction, also known as Ogilvie's syndrome.</p> <p>Conclusion</p> <p>This case report highlights the rare, but potentially dangerous, diagnosis of Ogilvie's syndrome after Caesarean section. It is of particular interest to obstetricians, midwifery staff and general surgeons and shows the importance of accurate diagnosis, regular abdominal reassessment and early senior input to ensure appropriate and rapid treatment.</p
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