4,029 research outputs found

    Structural style of the Laramide orogeny, Wyoming foreland. (Volumes I and II)

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    Thesis (Ph.D.) University of Alaska Fairbanks, 1987This study documents the styles of Laramide structures of the Wyoming foreland, and presents an integrated synthesis of foreland development. Theoretical data and experimental results are compared to field observations, subsurface well control, and geophysical data to judge their application to the foreland. The direction of collision (N40-50E) between the North American and Farallon plates represents the direction of maximum compressive stresses during the Laramide orogeny. A "tectonic front" progressed from west to east across the foreland during Campanian to middle Eocene time. No single model of uplift applies throughout the foreland. Dips of basement faults vary with changes in strike (i.e. northwest strike: 20-45 degrees; north to north-northwest strike: 45-60 degrees; east to northeast strike: 60 degrees to vertical). Northwest-trending uplifts are fold-thrust structures exhibiting dual fault systems and rotated flanks. North-northwest trending uplifts are thrust uplift structures bounded by single reverse faults. East- and northeast-trending uplifts are drape folds and upthrust structures along which displacements were dominantly vertical. The forms of Laramide structures were controlled by upward movement of basement forcing blocks, arrangement of lithology into mechanical packages, and deformational mechanisms which were determined by dominant lithology, applied stresses, and depth of burial. "Crowd" structures (i.e. back-limb, cross-crestal, and rabbit-ear folds) developed as volumetric adjustments in upward-tightening, parallel-folded synclines. There is no consistent relationship between basement fabric and northwest-trending Laramide structures; however, reactivated Precambrian-age zones of weakness controlled east- and northeast-trending compartmental faults, which intersect and segment other trends. As a result, northwest-trending thrust and fold-thrust structures may change directions of asymmetry, be offset, or even replaced by other structural styles, while maintaining overall structural balance. This study has documented approximately 30 miles of crustal shortening (representing 15% strain), which was pervasive and uniform across the foreland

    Age validation of quillback rockfish (Sebastes maliger) using bomb radiocarbon

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    Rockfishes (Sebastes spp.) support one of the most economically important f isheries of the Pacific Northwest and it is essential for sustainable management that age estimation procedures be validated for these species. Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon (14C) signal in the ocean environment that scientists have identified as a useful tracer and chronological marker in natural systems. In this study, we first demonstrated that fewer samples are necessary for age validation using the bomb-generated 14C signal by emphasizing the utility of the time-specific marker created by the initial rise of bomb-14C. Second, the bomb-generated 14C signal retained in fish otoliths was used to validate the age and age estimation method of the quillback rockfish (Sebastes maliger) in the waters of southeast Alaska. Radiocarbon values from the first year’s growth of quillback rockfish otoliths were plotted against estimated birth year to produce a 14C time series spanning 1950 to 1985. The initial rise in bomb-14C from prebomb levels (~ –90‰) occurred in 1959 [±1 year] and 14C levels rose relatively rapidly to peak Δ14C values in 1967 (+105.4‰) and subsequently declined through the end of the time series in 1985 (+15.4‰). The agreement between the year of initial rise of 14C levels from the quillback rockfish time series and the chronology determined for the waters of southeast Alaska from yelloweye rockfish (S. ruberrimus) otoliths validated the aging method for the quillback rockfish. The concordance of the entire quillback rockfish 14C time series with the yelloweye rockfish time series demonstrated the effectiveness of this age validation technique, confirmed the longevity of the quillback rockfish up to a minimum of 43 years, and strongly confirms higher age estimates of u

    Performance Control in Wireless Sensor Networks

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    Most of the currently deployed wireless sensor networks applications do not require performance control. The goal of the GINSENG project is sensor networks that meet application-specific performance targets, in particular with respect to latency and reliability. We present scenarios within the GALP oil re¿nery where the system will be deployed and some initial technical insights with respect to deterministic communication

    Journeys to identity : why care records matter

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    Care experienced people often find themselves applying for their care records in search of answers — to address gaps and inconsistencies in the knowledge they hold about their childhoods and personal development, which may in turn affect their broader senses of self. This article, written from our own lived experiences, provides a commentary on a system of writing, accessing and reading records which is not aligned to the circumstances and purposes of care experienced people and which indeed frequently disempowers and (re-)traumatises. We share our experiences of applying for and reading our records, as an adoptee and as a care experienced person. We also draw on the discussions and experiences of a Who Cares? Scotland care records campaign group. This commentary reveals the power imbalance at the heart of record keeping where the rights to memory, identity, and childhood are effectively questioned. It also makes suggestions for future practice. It asks for a complete rethinking of how care records are regarded by professionals and the sector, advocating for a shift in power as regards the production and control of information and a significant improvement in the care offered to those of us who choose to access it

    The relative importance of subjective and structural factors for individual adaptation to climate change by forest owners in Sweden

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    A growing body of literature argues that subjective factors can more accurately explain individual adaptation to climate change than objective measurers of adaptive capacity. Recent studies have shown that personal belief in climate change and affect are much better in explaining climate awareness and action than income, education or gender. This study focuses on the process of individual adaptation to climate change. It assesses and compares the influence of cognitive, experiential and structural factors on individuals’ views and intentions regarding climate change adaptation. Data from this study comes from a survey with 836 forest owners in Sweden. Ordinal and binary logistic regression was used to test hypotheses about the different factors. Results show that cognitive factors—namely personal level of trust in climate science, belief in the salience of climate change and risk assessment—are the only statistically significant factors that can directly explain individuals’ intention to adapt to climate change and their sense of urgency. Findings also suggest that structural or socio-demographic factors do not have a statistically significant influence on adaptation decision-making among Swedish forest owners. The study also offers valuable insights for communication interventions to promote adaptation. Findings strongly suggest that communication interventions should focus more strongly on building trust and addressing stakeholders’ individual needs and experiences

    Enteral supplementation with probiotics in preterm infants: A retrospective cohort study and 6-year follow-up

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    The objective of this retrospective cohort study was to assess the impact of an enteral probiotics supplementation protocol on the incidence of necrotizing enterocolitis (NEC) in infants born <33 weeks gestational age (GA) or birth weight (BW) <1,500 g. In addition, a 6-year follow-up is presented after instigation of probiotic use. In October 2014, our NICU introduced an enteral probiotics supplementation protocol for infants born <33 weeks GA or BW <1,500 g. Infants received 0.5 g of Bifidobacterium breve HA-129, Lacticaseibacillus rhamnosus HA-111, Bifidobacterium bifidum HA-132, Bifidobacterium longum subsp. infantis HA-116, and Bifidobacterium longum subsp. longum HA-135 (FloraBABYⓇ) daily until discharge or transfer from hospital. The incidence of NEC was compared among infants for 2 years pre- and post implementation of the protocol then 6-years following continuous implementation of the probiotic use. In total, 370 infants not treated with probiotics between 2012 and 2014 were included with an incidence of NEC at 4.9%. In comparison, the 367 infants who received had a 67% reduction (4.9–1.6%, p = 0.01) in our Neonatal Intensive Care Unit (NICU). The results remained significant (aOR = 0.26; 95% CI: 0.09, 0.72; p < 0.01) after adjusting for GA, small for gestational age, and antenatal corticosteroid use. Data from the Canadian Neonatal Network not only showed a consistently high rate of NEC in October 2014, but also identified exceedingly high rates (8.7–15.6%) in some hospitals up to 2021, while our rates have been consistently low with using the probiotic as standard therapy for low BW premature babies, with no serious side effects reported. In conclusion, the introduction of a five-strain probiotic natural health product has coincided with a reduced incidence and complications of NEC in our NICU setting

    Large-scale insertional mutagenesis of a coleopteran stored grain pest, the red flour beetle Tribolium castaneum, identifies embryonic lethal mutations and enhancer traps

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    <p>Abstract</p> <p>Background</p> <p>Given its sequenced genome and efficient systemic RNA interference response, the red flour beetle <it>Tribolium castaneum </it>is a model organism well suited for reverse genetics. Even so, there is a pressing need for forward genetic analysis to escape the bias inherent in candidate gene approaches.</p> <p>Results</p> <p>To produce easy-to-maintain insertional mutations and to obtain fluorescent marker lines to aid phenotypic analysis, we undertook a large-scale transposon mutagenesis screen. In this screen, we produced more than 6,500 new <it>piggyBac </it>insertions. Of these, 421 proved to be recessive lethal, 75 were semi-lethal, and eight indicated recessive sterility, while 505 showed new enhancer-trap patterns. Insertion junctions were determined for 403 lines and often appeared to be located within transcription units. Insertion sites appeared to be randomly distributed throughout the genome, with the exception of a preference for reinsertion near the donor site.</p> <p>Conclusion</p> <p>A large collection of enhancer-trap and embryonic lethal beetle lines has been made available to the research community and will foster investigations into diverse fields of insect biology, pest control, and evolution. Because the genetic elements used in this screen are species-nonspecific, and because the crossing scheme does not depend on balancer chromosomes, the methods presented herein should be broadly applicable for many insect species.</p

    Field quantization for open optical cavities

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    We study the quantum properties of the electromagnetic field in optical cavities coupled to an arbitrary number of escape channels. We consider both inhomogeneous dielectric resonators with a scalar dielectric constant ϵ(r)\epsilon({\bf r}) and cavities defined by mirrors of arbitrary shape. Using the Feshbach projector technique we quantize the field in terms of a set of resonator and bath modes. We rigorously show that the field Hamiltonian reduces to the system--and--bath Hamiltonian of quantum optics. The field dynamics is investigated using the input--output theory of Gardiner and Collet. In the case of strong coupling to the external radiation field we find spectrally overlapping resonator modes. The mode dynamics is coupled due to the damping and noise inflicted by the external field. For wave chaotic resonators the mode dynamics is determined by a non--Hermitean random matrix. Upon including an amplifying medium, our dynamics of open-resonator modes may serve as a starting point for a quantum theory of random lasing.Comment: 16 pages, added references, corrected typo

    Causal evidence that intrinsic beta frequency is relevant for enhanced signal propagation in the motor system as shown through rhythmic TMS

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    Correlative evidence provides support for the idea that brain oscillations underpin neural computations. Recent work using rhythmic stimulation techniques in humans provide causal evidence but the interactions of these external signals with intrinsic rhythmicity remain unclear. Here, we show that sensorimotor cortex precisely follows externally applied rhythmic TMS (rTMS) stimulation in the beta-band but that the elicited responses are strongest at the intrinsic individual beta-peak-frequency. While these entrainment effects are of short duration, even subthreshold rTMS pulses propagate through the network and elicit significant cortico-spinal coupling, particularly when stimulated at the individual beta-frequency. Our results show that externally enforced rhythmicity interacts with intrinsic brain rhythms such that the individual peak frequency determines the effect of rTMS. The observed downstream spinal effect at the resonance frequency provides evidence for the causal role of brain rhythms for signal propagation
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