Using otolith strontium isotopes to elucidate population structure and movements of Bering cisco (Coregonus laurettae)

Thesis (M.S.) University of Alaska Fairbanks, 2015Methods for stock discrimination and tracking the movements and distribution of fishes have often involved expensive field logistics, a problem compounded in remote regions such as Alaska. An alternative approach is to use the chemical signatures preserved in otoliths, or ear bones, of teleost fishes to discriminate stocks or to track the movement history of fish. Currently, a commercial fishery targeting the anadromous Bering cisco Coregonus laurettae is occurring in the Yukon River, Alaska. There are only three known Bering cisco spawning rivers worldwide, the Yukon, South Fork Kuskokwim (Kuskokwim), and Susitna rivers. Managers and researchers believed that two of the three spawning-river populations (Yukon and Kuskokwim rivers) were being harvested in the fishery, due to major coastal currents linking two of the spawning rivers' deltas. To determine the likelihood of a mixed-stock fishery, in Chapter 1, I used the strontium isotope signature (⁸⁷Sr/⁸⁶Sr) preserved in the freshwater portion of otoliths to establish a baseline for the three natal rivers. The baseline data set was composed of otoliths from spawning adult Bering cisco of known origin (n=82). Subsequently, the baseline was used to classify commercially harvested Bering cisco (n=139) and determine the stock composition of the fishery. Greater than 97% of the commercial samples were classified as Yukon River origin. However, 0.7%, and 1.4% of the commercial samples were classified as originating from Kuskokwim and Susitna rivers, respectively. In Chapter 2, I used the baseline data to classify Bering cisco from three coastal rearing areas (Alaska Arctic coast, n=49; Y-K Delta, n=70; and the Alaska Peninsula, n=8). More than 96% of the coastal rearing Bering cisco had ⁸⁷Sr/⁸⁶Sr signatures consistent with a Yukon River origin. These data demonstrate the wide-spread coastal distribution of Bering cisco, with some travelling >4,900 km between coastal rearing and spawning habitats. This approach illustrates that ⁸⁷Sr/⁸⁶Sr can determine the natal river of Bering cisco. Subsequently, this method can be used for stock discrimination and elucidating migration patterns for unknown origin Bering cisco

Applying PII fingerprints in security incident analysis

Regulations in many countries govern the use of personally identifiable information (PII) in IT systems. A key aspect of these regulations is to retain PII only as long as necessary and delete it immediately afterwards. Organizations should also consider retaining PII only for the minimum period as business requirements demand it for liability reasons. A difficult sit-uation arises for an organization if the possibility of a compromise of PII is detected after the PII has been deleted. Today, in such a situation, the scope of the potential compromise cannot easily be ascertained. Furthermore, the owner of the PII cannot easily be informed. We propose a novel algorithm to generate PII fingerprints which allows the determination of the scope of the affected PII in case a compromise is confirmed. The benefit is the ability to determine the exact scope of a potential compromise

Ringdowns for black holes with scalar hair: the large mass case

Deviations from General Relativity can alter the quasi-normal mode (QNM) ringdown of perturbed black holes. It is known that a shift-symmetric (hence massless) scalar can only introduce black hole hair if it couples to the Gauss-Bonnet invariant, in which case the scalar charge is fixed with respect to the black hole mass and controlled by the strength of that coupling. The charge per unit mass decreases with the mass and can, therefore, be used as a perturbative parameter for black holes that are sufficiently large with respect to the scale suppressing the deviation from General Relativity or the Standard model. We construct an effective field theory scheme for QNMs using this perturbative parameter to capture deviations from Kerr for both the background and the perturbations. We demonstrate that up to second order in the charge per unit mass, QNMs can be calculated by solving standard linearised perturbation equations for the Kerr metric with sources depending on solutions of the same equations up to first order. It follows that corrections to the QNM frequencies are heavily suppressed for sufficiently massive black holes, meaning that LISA is very unlikely to detect any evidence of scalar hair in ringdown signals.Comment: 6 page

Kinect-based RGB detection for 'smart' costume interaction.

This paper is an overview of a Kinect-based RGB detection software developed as part of an ongoing 'Smart' (Smart Textiles and Wearable Technology in Pervasive Computing Environments) Costume project. The project involved a multi-disciplinary team in the domains of textile design, engineering and computer science. In this work we aimed to establish initial studies on how the Microsoft Kinect performs in tracking a "smart" lighting conditions. We explain the computer application capable of detecting, tracking and measuring colour changes (Red, Blue and Green) created using the Microsoft Kinect API

Kinect-based RGB detection for 'smart' costume interaction.

This paper is an overview of a Kinect-based RGB detection software developed as part of an ongoing 'Smart' (Smart Textiles and Wearable Technology in Pervasive Computing Environments) Costume project. The project involved a multi-disciplinary team in the domains of textile design, engineering and computer science. In this work we aimed to establish initial studies on how the Microsoft Kinect performs in tracking a "smart" lighting conditions. We explain the computer application capable of detecting, tracking and measuring colour changes (Red, Blue and Green) created using the Microsoft Kinect API

Dynamic distribution of the replacement histone variant H3.3 in the mouse oocyte and preimplantation embryos

Upon fertilization, the gametes undergo a drastic reprogramming that includes changes in DNA methylation and histone modifications. Currently, it is not known whether replacement of the major histones by histone variants is also involved in these processes. Here we have examined the expression and localization of the histone variant H3.3 in early mouse embryogenesis. We show that H3.3 is present in the oocyte as a maternal factor. It is then incorporated preferentially into the male pronucleus before genome activation, pointing towards an asymmetry in histone composition between the two pronuclei. This is in line with the male pronucleus bearing transcriptional activation first. The same distribution was observed when we followed the localisation of a tagged version of H3.3. We detected H3.3 in the nuclei of mouse embryos in all of the stages analysed, from the zygote to the blastocyst stage, suggesting that the epigenetic mechanisms in the early embryo not only involve changes in histone modifications but may also include histone replacement

Multiple Hazard Uncertainty Visualization Challenges and Paths Forward

Making decisions with uncertainty is challenging for the general public, policymakers, and even highly trained scientists. Nevertheless, when faced with the need to respond to a potential hazard, people must make high-risk decisions with uncertainty. In some cases, people have to consider multiple hazards with various types of uncertainties. Multiple hazards can be interconnected by location, time, and/or environmental systems, and the hazards may interact, producing complex relationships among their associated uncertainties. The interaction between multiple hazards and their uncertainties can have nonlinear effects, where the resultant risk and uncertainty are greater than the sum of the risk and uncertainty associated with individual hazards. Effectively communicating the uncertainties related to such complicated systems should be a high priority because the frequency and variability of multiple hazard events due to climate change continue to increase. However, the communication of multiple hazard uncertainties and their interactions remains largely unexplored. The lack of practical guidance on conveying multiple hazard uncertainties is likely due in part to the field’s vast expanse, making it challenging to identify entry points. Here, we offer a perspective on three critical challenges related to uncertainty communication across various multiple hazard contexts to galvanize the research community. We advocate for systematic considerations of multiple hazard uncertainty communication that focus on trade-offs between complexity and factors, including mental effort, trust, and usability

Molecular phylogeny of Burkholderia pseudomallei from a remote region of Papua New Guinea

Background The island of New Guinea is located midway between the world's two major melioidosis endemic regions of Australia and Southeast Asia. Previous studies in Papua New Guinea have demonstrated autochthonous melioidosis in Balimo, Western province. In contrast to other regions of endemicity, isolates recovered from both environmental and clinical sources demonstrate narrow genetic diversity over large spatial and temporal scales. Methodology/Principal Findings We employed molecular typing techniques to determine the phylogenetic relationships of these isolates to each other and to others worldwide to aid in understanding the origins of the Papua New Guinean isolates. Multi-locus sequence typing of the 39 isolates resolved three unique sequence types. Phylogenetic reconstruction and Structure analysis determined that all isolates were genetically closer to those from Australia than those from Southeast Asia. Gene cluster analysis however, identified a Yersinia-like fimbrial gene cluster predominantly found among Burkholderia pseudomallei derived from Southeast Asia. Higher resolution VNTR typing and phylogenetic reconstruction of the Balimo isolates resolved 24 genotypes with long branch lengths. These findings are congruent with long term persistence in the region and a high level of environmental stability. Conclusions/Significance Given that anthropogenic influence has been hypothesized as a mechanism for the dispersal of B. pseudomallei, these findings correlate with limited movement of the indigenous people in the region. The palaeogeographical and anthropogenic history of Australasia and the results from this study indicate that New Guinea is an important region for the further study of B. pseudomallei origins and dissemination

Lean Manufacturing para mejorar la productividad en la fabricación de cobertores para camiones en la empresa Novofibras

El presente trabajo de investigación estuvo enfocado en mejorar la productividad en la fabricación de cobertores para camiones de la empresa Novofibras, una empresa manufacturera dedicada a fabricar toda clase de productos en fibra de vidrio; esta mejora fue basada en el uso de herramientas de Lean manufacturing. La investigación fue del tipo aplicado, teniendo un enfoque cuantitativo y un método explicativo. La elección del producto “cobertor” se dio mediante el diagrama de Pareto para los productos de la empresa, siendo el producto que genera mayor ingreso a la empresa; de esta elección, se identificaron los problemas que generaban baja productividad usando el diagrama Ishikawa, estos fueron los defectos de fabricación, reprocesos y paros no planificados del equipo auxiliar. El análisis de los datos se dio en el periodo enero a junio del año 2019, el cual fue utilizado para hacer de símil con sus posteriores datos para el mismo semestre del año 2021. Se implementó el ciclo PDCA con el objetivo de reducir la cantidad de defectos generados, obteniendo resultados muy favorables en el corto plazo; para reducir la cantidad de reprocesos por errores en mano de obra se implementó el trabajo estandarizado, gracias a esto, el proceso tuvo un mejor rendimiento. Se implementó el mantenimiento planeado con el fin de aumentar el tiempo de actividad del equipo auxiliar al reducir los paros no planificados del compresor de aire, que es el punto crítico en el proceso de fabricación de los cobertores, debido a que es fundamental en los procesos de pintado, el cual es cuello de botella del proceso. Mediante la implementación del ciclo PDCA se redujeron los defectos en un 54 %, la implementación del trabajo estandarizado, los reprocesos por errores en mano de obra se redujeron en un 63.11 % y mediante el mantenimiento planeado, las horas de actividad del compresor aumentaron en un 10.07 %

On measuring the covariance matrix of the nonlinear power spectrum from simulations

We show how to estimate the covariance of the power spectrum of a statistically homogeneous and isotropic density field from a single periodic simulation, by applying a set of weightings to the density field, and by measuring the scatter in power spectra between different weightings. We recommend a specific set of 52 weightings containing only combinations of fundamental modes, constructed to yield a minimum variance estimate of the covariance of power. Numerical tests reveal that at nonlinear scales the variance of power estimated by the weightings method substantially exceeds that estimated from a simple ensemble method. We argue that the discrepancy is caused by beat-coupling, in which products of closely spaced Fourier modes couple by nonlinear gravitational growth to the beat mode between them. Beat-coupling appears whenever nonlinear power is measured from Fourier modes with a finite spread of wavevector, and is therefore present in the weightings method but not the ensemble method. Beat-coupling inevitably affects real galaxy surveys, whose Fourier modes have finite width. Surprisingly, the beat-coupling contribution dominates the covariance of power at nonlinear scales, so that, counter-intuitively, it is expected that the covariance of nonlinear power in galaxy surveys is dominated not by small scale structure, but rather by beat-coupling to the largest scales of the survey.Comment: 19 pages, 4 figures. To appear in Monthly Notices of the Royal Astronomical Society. Revised to match accepted versio