The Biological Setting of the BIOS Site at Cape Hatt, N.W.T., Including the Sampling Design, Methodology and Baseline Results for Macrobenthos

The Baffin Island Oil Spill (BIOS) Project was carried out in nearshore shallow waters at Cape Hatt, northern Baffin Island. Observations and limited data on phytoplankton, zooplankton, fishes, birds and mammals at Cape Hatt and more detailed information on microheterotrophs indicate that the BIOS site is typical of the majority of eastern and central High Arctic coastal areas. Detailed baseline information on nearshore macrobenthos (infauna, epibenthos and macroalgae) is, in general, similar to that previously reported for other eastern and central arctic locations; comparisons were hindered by a scarcity of detailed studies elsewhere, differences in sampling methods and complexity in infaunal community structure. ... An evaluation of the sampling design and procedures used in this study (including efficiency of the diver-operated airlife sampler, the area, location and number of replicate samples collected; and bias, efficiency and consistency in laboratory analysis) indicated that representative samples of the nearshore macrobenthic communities were obtained. The study design and analysis of variance procedures used to analyze the data provided a rigorous framework within which oil effects were evaluated. Key words: Arctic, benthos, phytoplankton, bacteria, benthic sampling design, sediment, experimental oil releases, Baffin Island, baseline, microheterotrophMots clés: Arctique, benthos, phytoplancton, bacteries, plan de l’échantillonnage du benthos, sédiments, déversements de pétrole expérimentaux, île Baffin, base de réftrence, micro-hétkotroph

The Influence of Racial Identity Profiles on the Relationship Between Racial Discrimination and Depressive Symptoms

This study examined the association between racial identity profiles, discrimination, and mental health outcomes. African American college students (N = 194) completed measures of racial discrimination, racial identity, college hassles, and depressive symptoms. Four meaningful profiles emerged through a cluster analysis of seven dimensions of racial identity assessed using the Multidimensional Inventory of Black Identity (MIBI). Results suggested racial identity moderates the relation between discrimination and depressive symptoms. Students whose racial identity profile involves the goal of blending with the mainstream and focusing on shared human qualities rather than race as a core ideological concept had a significantly stronger association between racial discrimination and depressive symptoms. The results hold implications for investigating the experience of racial discrimination and conceptualization of racial identity

Volume I. Introduction to DUNE

The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE\u27s physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology

Deep Underground Neutrino Experiment (DUNE), far detector technical design report, volume III: DUNE far detector technical coordination

The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. Volume III of this TDR describes how the activities required to design, construct, fabricate, install, and commission the DUNE far detector modules are organized and managed. This volume details the organizational structures that will carry out and/or oversee the planned far detector activities safely, successfully, on time, and on budget. It presents overviews of the facilities, supporting infrastructure, and detectors for context, and it outlines the project-related functions and methodologies used by the DUNE technical coordination organization, focusing on the areas of integration engineering, technical reviews, quality assurance and control, and safety oversight. Because of its more advanced stage of development, functional examples presented in this volume focus primarily on the single-phase (SP) detector module

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

On the confidence bounds of Gaussian process NARX models and their higher-order frequency response functions

One of the most powerful and versatile system identification frameworks of the last three decades is the NARMAX/NARX 1 approach, which is based on a nonlinear discrete-time representation. Recent advances in machine learning have motivated new functional forms for the NARX model, including one based on Gaussian processes (GPs), which is the focus of this paper. Because of their nonparametric form, NARX models can only provide physical insight through their frequency-domain connection to Higher-order Frequency Response Functions (HFRFS). Because of the desirable properties of the GP-NARX form (no structure detection needed, natural confidence i ntervals), the analytical derivation of the HFRFs for the model is presented here for the first time. Furthermore, an algorithm for propagating uncertainty from the GP into the HFRF estimates is presented. A valuable by-product of the latter algorithm is a new test for nonlinearity, capable of detecting the presence of odd and even system nonlinearities. The new results are illustrated via two case studies; the first is based on simulation of an asymmetric Duffing oscillator. The second case study presents a validation of the new theory in the area of wave force prediction on offshore structures. This problem is one that has been considered by some of the authors before; the current paper takes the opportunity to highlight and correct a number of weaknesses of the original study in the light of modern best practice in machine learning