2,425 research outputs found

    An assessment of the mantle and slab components in the magmas of an oceanic arc volcano: Raoul Volcano, Kermadec arc

    Get PDF
    Raoul Volcano occupies a simple oceanic subduction setting in the northern part of the Kermadec arc on the Pacific–Australian convergent plate boundary. The primary inputs to the magmatic system that feeds the volcano are a subduction component derived from the subducting old Pacific oceanic lithosphere and its veneer of pelagic sediment, and the overlying peridotitic mantle wedge. Conservative trace elements that are very incompatible during mantle melting are relatively depleted in Raoul lavas indicating a source that has been depleted during an earlier melting event. Major element co-variations indicate magma genesis by 25% near fractional melting of a mantle source that is weakly depleted (2% melt extraction) relative to a fertile MORB source. An important influence on the composition of the mantle component is progressive melt extraction coupled with minimal advection of fresh material into the sub-arc zone followed by melt extraction from a melting column beneath the spreading centre of an adjacent back arc basin. High field strength element and rare earth element systematics indicate involvement of a subduction-related component of constant composition. Two fluid components can be distinguished, one enriched in large ion lithophile elements inferred to be an aqueous fluid that is continuously added to the ascending melt column and the other a less mobile fluid that transfers Th. A homogeneous subduction-related component of constant composition and magnitude arises if the slab-derived flux migrates from the slab–mantle interface to the sub-arc melting column by repeated episodes of amphibole formation and decomposition its composition is then governed by the distribution coefficients of pyroxene and its magnitude by the degree of amphibole saturation of mantle peridotite. The results from Raoul Volcano are comparable to those from other oceanic subduction-related arcs such as South Sandwich and Marianas suggesting that this is a general model for oceanic arcs

    Insect (Arthropoda: Insecta) Composition in the Diet of Ornate Box Turtles (Terrapene ornata ornata) in Two Western Illinois Sand Prairies, with a New State Record for Cyclocephala (Coleoptera: Scarabaeidae)

    Get PDF
    A study of fecal samples collected over a two-year period from juvenile ornate box turtles (Terrapene ornata ornata Agassiz) revealed diets consisting of six orders of insects representing 19 families. Turtles were reared in captivity from eggs harvested from local, wild populations, and released at two remnant prairies. Identifiable insect fragments were found in 94% of samples in 2013 (n=33) and 96% in 2014 (n=25). Frequency of occurrence of insects in turtle feces is similar to results reported in previous studies of midwestern Terrapene species. A comparison of insect composition presented no significant difference between release sites. There is no significant difference in consumed insect species between turtles released into or outside of a fenced enclosure at the same site. Specimens of Cyclocephala longula LeConte collected during this study represent a new state record for Illinois

    Scanwave: A New Approach to Enhancing Spectral Data on a Tandem Quadrupole Mass Spectrometer

    Get PDF
    A new type of mass analyzer is described, which allows low-resolution axial ion ejection to be obtained from a traveling wave based, stacked ring collision cell. Linking this ejection temporally with the scanning of the second quadrupole of a tandem quadrupole mass spectrometer provides an improvement in sampling duty cycle, which results in significant signal intensity improvements for scanning acquisitions such as product ion spectra. A near 100% storage efficiency is enabled by a split cell design, which allows ion fragmentation and accumulation to be performed in one section of the collision cell whilst previously accumulated ions are simultaneously ejected from the rear of the cell. These characteristics combine to give an m/z-dependent signal gain of 7–20× over a conventional scanning quadrupole for a 1000 Th scan. The ability to swap very rapidly from a non-enhanced mode of operation to an enhanced mode whilst retaining the existing sensitivity, speed, and functionality of a conventional tandem quadrupole mass spectrometer is also described

    Studies in Experimental Design and Data Analysis with Special Reference to Computational Problems

    Get PDF
    An experimenter, designing or analysing an experiment, frequently finds that not all can be done according to the text-book. Considerations outside his control may have to be taken into account that affect the design; he may not be interested in all his treatments equally but perhaps in some unusual contrasts between them. Again, unforseen circumstances and happenings can afterwards force him to discard some of his results, so upsetting the balance or orthogonality of the design. The aim of this thesis is to help an experimenter in such a situation. The first part is concerned with analysing a block experiment that is in general unbalanced and non-orthogonal. 'Two different methods, one iterative, one non-iterative, are derived for obtaining the analysis, each with its own advantages. The non-iterative method basically is derived from the actual design and produces matrices, which can then operate on any suitable data supplied. The iterative method, however, found in appendix A, is applied directly to the data from the start, to produce the treatment effects directly. Although the iterative method is easier to apply and can also be used with a wider class of design than can the non-iterative method, the inter-block analysis and the analysis of the dual become easier using the non-iterative method. Certain contrasts are related to the design in special ways, and, if known, make the analysis of the design easier. The implications are discussed in chapter 2, which is also concerned with finding the contribution to the sum of squares for these and other, more general, contrasts of interest. The dual of a design is defined as that design formed from the original design when treatments and blocks classifications are interchanged, i.e. treatments become blocks and vice-versa in the new design. It is useful for studying block differences eliminating those due to treatments, which may, for example, be required if the blocking system arose from the possible residual effects of treatments from some previous experiment on the same material. The second part of the thesis, in chapter 3> is concerned with the analysis of the dual. It is shown that there is no need to start again from the beginning when analysing the dual if the original design had already been analysed, because the analysis can provide information about that of the dual. The method is especially easy when the non-iterative method of analysing block designs, discussed in chapter 2, has been used for the original design. The experimenter will often be more interested in some contrasts between treatments than in others and a design can be selected to give more precise information about these contrasts. The construction of such designs is discussed in the third part of the thesis. Various measures can be used to judge which design is best as regards contrasts of interest. Algorithms for finding the optimal design according to these measures are derived and discussed in chapter 4. Listings and flowcharts of a program to carry out the non-iterative analysis of chapter 2 and of a program to construct optimal block designs appear in appendices B and C

    An Evaluation of the Teacher Preparation Program at Central Washington College of Education

    Get PDF
    It was the purpose of this study (1) to establish the strengths and weaknesses of beginning teachers as seen by themselves and by their supervisors; (2) to compile suggestions of the beginning teachers and their supervisors for the improvement of the college preparatory program made in the light of the reported strengths and weaknesses; and (3) to analyze the reported strengths and weaknesses of beginning teachers and the suggestions for improvement for the specific purpose of making recommended changes in the teacher preparation curriculum

    A survey of research and scientific services in East Africa, 1947-56

    Get PDF
    This "Survey of Research and Scientific Services in East Arica 1947-1956" has been prepared by Dr. E. B. Worthington, who held the post of Scientific Secretary in the Office of the Chief Secretary to the East African Governor's Conference and subsequently in the Administrator's Office of the East Mrica High Commission during the period January, 1947-May, 1951. Dr. Worthington is now Secretary General of the Scientific Council for, Arica South of the Sahar

    Evaluation of the regional nurse-supported hepatitis C shared care program in Western Australia: a mixed methods study

    Get PDF
    Background: Nurse-supported shared care services for patients living with hepatitis C have been implemented in some regional areas of Western Australia to provide access to local treatment and care services for patients and to improve currently low levels of treatment uptake. This study collected data from health professionals involved in managing the care of patients living with hepatitis C and from patients engaged in regional nurse-supported hepatitis C shared care services in Western Australia. Methods: Key informant qualitative interviews were conducted with health professionals in regions operating a nurse-supported shared care service and in regions without this service. Patients engaged in the shared care program at the time of the study were invited to complete a short questionnaire. Results: Nurse-supported shared care services reduced patient transport costs to tertiary centres, accelerated access to treatment and delivered \u3e98 % compliance with treatment schedules. Patients engaged with regional hepatitis C shared care services expressed high levels of satisfaction and indicated that they would delay treatment if it was not available locally. Telehealth support from tertiary liver clinics and allied health services were available to health professionals engaged in regional shared care services and were used effectively. There was limited participation by general practitioners in regional hepatitis C shared care services and regional patients’ access to treatment was influenced by the availability and capacity of health professionals. Uptake of treatment and engagement in the regional shared care program was limited for Aboriginal people and younger people although these groups had the highest rates of hepatitis C notifications in Western Australia. Discussion: The patients consulted for this study preferred to access hepatitis C treatment and care locally rather than travel to tertiary liver clinics, up to 1500 kilometres away. The reasons for limited engagement in the shared care program by some groups with high rates of hepatitis C notifications requires further investigation. Health professionals identified several benefits of the shared care program including continuity of care for patients, shorter waiting times, longer appointment times and high levels of treatment compliance. Conclusions: Hepatitis nurses in regional areas can coordinate effective patient treatment and care when supported by treatment protocols and access to physicians and liver specialists, including through telehealth. Treatment and care options to suit individual preferences are required to avoid further stigmatising marginalized groups. The role of primary care in facilitating hepatitis C treatment uptake should be explored further including strategies for improving the participation of general practitioners in regional shared care services

    Pasts and pagan practices: moving beyond Stonehenge

    Get PDF
    Theorizing the past is not restricted to archaeology and interpretations of 'past' both influence and are themselves constituted within politicized understandings of self, community and in certain instances, spirituality. 'The past in the imagination of the present' is appropriated, variously, to give meaning to the present or to justify actions and interpret experiences. Summer solstice at Stonehenge, with an estimated 21,000 celebrants in 2005, is only the most publicized appropriation (by pagans and other adherents of alternative spirituality and partying) of a 'sacred site'; and conflicts and negotiations occurring throughout Britain are represented in popular and academic presentations of this 'icon of Britishness'. This paper presents work from the Sacred Sites, Contested Rites/Rights Project (http://www.sacredsites.org.uk) project, a collaboration of archaeology and anthropology informed by pagan and alternative approaches and standpoints investigating and theorizing discourse and practice of heritage management and pagan site users. Whether in negotiations around the Stonehenge solstice access or in dealing with numerous other sites, boundaries between groups or discourses are not clearly drawn - discursive communities merge and re-emerge. But clearly 'past' and 'site' are increasingly important within today's Britain, even as television archaeology increases its following, and pagan numbers continue to grow.</p

    Genetic susceptibility to psoriasis: an emerging picture

    Get PDF
    Psoriasis is recognized as a complex disease for which multiple genetic and non-genetic factors influence susceptibility. The major susceptibility locus resides in the MHC class I region and, until relatively recently, evidence for non-MHC loci was inconsistent. Like many common diseases, knowledge of the genetic basis of this condition has been advanced dramatically in recent times with the advent of genome-wide association studies using single nucleotide polymorphisms. Here, we give an overview of current knowledge of genetic risk factors for psoriasis and consider emerging studies that may further add to our understanding of the genetic basis of the disease

    Insect (Arthropoda: Insecta) Composition in the Diet of Ornate Box Turtles (Terrapene ornata ornata) in Two Western Illinois Sand Prairies, with a New State Record for Cyclocephala (Coleoptera: Scarabaeidae)

    Get PDF
    A study of fecal samples collected over a two-year period from juvenile ornate box turtles (Terrapene ornata ornata Agassiz) revealed diets consisting of six orders of insects representing 19 families. Turtles were reared in captivity from eggs harvested from local, wild populations, and released at two remnant prairies. Identifiable insect fragments were found in 94% of samples in 2013 (n=33) and 96% in 2014 (n=25). Frequency of occurrence of insects in turtle feces is similar to results reported in previous studies of midwestern Terrapene species. A comparison of insect composition presented no significant difference between release sites. There is no significant difference in consumed insect species between turtles released into or outside of a fenced enclosure at the same site. Specimens of Cyclocephala longula LeConte collected during this study represent a new state record for Illinois
    corecore