A new aluminum sand casting alloy of high toughness /M-45/

High toughness aluminum sand casting alloy for cryogenic application

Shellfish Tissue Monitoring in Piscataqua Region Estuaries 2010 and 2011

Conducted by a committee of Canadian and US government and university scientists, Gulfwatch examines the effects of decades of development and industrialization on the water quality of the Gulf as it relates to human health primarily through assessing contaminant exposure of marine organisms. Gulfwatch scientists collect blue mussels at over 60 US and Canadian sites Gulfwide, and analyze the organisms’ tissue for potentially harmful levels and concentrations of toxins including heavy metals, chlorinated pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs)

Strange pulsation modes in luminous red giants

We show that the spectrum of radial pulsation modes in luminous red giants consists of both normal modes and a second set of modes with periods similar to those of the normal modes. These additional modes are the red giant analogues of the strange modes found in classical Cepheids and RR Lyrae variables. Here, we describe the behaviour of strange and normal modes in luminous red giants and discuss the dependence of both the strange and normal modes on the outer boundary conditions. The strange modes always appear to be damped, much more so than the normal modes. They should never be observed as self-excited modes in real red giants but they may be detected in the spectrum of solar-like oscillations. A strange mode with a period close to that of a normal mode can influence both the period and growth rate of the normal mode.Comment: 6 pages, 5 figures, accepted by MNRA

Shellfish Tissue Monitoring in Piscataqua Region Estuaries 2013

Originally conducted by the Gulf of Maine Council on the Marine Environment from 1993 to 2011, the Gulfwatch Program examined trends in the water quality of the Gulf of Maine by monitoring toxic contaminant concentrations in the tissues of shellfish. Starting in 2012 the Piscataqua Region Estuaries Partnership (PREP) continued this program in the Piscataqua Region. Each year, PREP collects blue mussels at three sites: Dover Point, NH (NHDP), Clark Cove on Seavey Island, ME (MECC), and Hampton-Seabrook Harbor (NHHS). The mussel tissue is analyzed to determine the concentrations of toxic contaminantss including heavy metals, chlorinated pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs)

Polynomial treewidth forces a large grid-like-minor

Robertson and Seymour proved that every graph with sufficiently large treewidth contains a large grid minor. However, the best known bound on the treewidth that forces an $\ell\times\ell$ grid minor is exponential in $\ell$. It is unknown whether polynomial treewidth suffices. We prove a result in this direction. A \emph{grid-like-minor of order} $\ell$ in a graph $G$ is a set of paths in $G$ whose intersection graph is bipartite and contains a $K_{\ell}$-minor. For example, the rows and columns of the $\ell\times\ell$ grid are a grid-like-minor of order $\ell+1$. We prove that polynomial treewidth forces a large grid-like-minor. In particular, every graph with treewidth at least $c\ell^4\sqrt{\log\ell}$ has a grid-like-minor of order $\ell$. As an application of this result, we prove that the cartesian product $G\square K_2$ contains a $K_{\ell}$-minor whenever $G$ has treewidth at least $c\ell^4\sqrt{\log\ell}$.Comment: v2: The bound in the main result has been improved by using the Lovasz Local Lemma. v3: minor improvements, v4: final section rewritte

Circumference and Pathwidth of Highly Connected Graphs

Birmele [J. Graph Theory, 2003] proved that every graph with circumference t has treewidth at most t-1. Under the additional assumption of 2-connectivity, such graphs have bounded pathwidth, which is a qualitatively stronger result. Birmele's theorem was extended by Birmele, Bondy and Reed [Combinatorica, 2007] who showed that every graph without k disjoint cycles of length at least t has bounded treewidth (as a function of k and t). Our main result states that, under the additional assumption of (k + 1)- connectivity, such graphs have bounded pathwidth. In fact, they have pathwidth O(t^3 + tk^2). Moreover, examples show that (k + 1)-connectivity is required for bounded pathwidth to hold. These results suggest the following general question: for which values of k and graphs H does every k-connected H-minor-free graph have bounded pathwidth? We discuss this question and provide a few observations.Comment: 11 pages, 4 figure

Shellfish Tissue Monitoring in Piscataqua Region Estuaries 2010: Final Report

Gulfwatch examines the effects of decades of development and industrialization on the water quality of the Gulf as it relates to human health primarily through assessing contaminant exposure of marine organisms. Gulfwatch scientists collect blue mussels at over 60 US and Canadian sites Gulfwide, and analyze the organisms’ tissue for potentially harmful levels and concentrations of toxins including heavy metals, chlorinated pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). New Hampshire increased the number of Gulfwatch sampling locations from two sites per year in 1997 to an average of five sites per year from 1998-2010. The increased spatial coverage provides comprehensive information for contaminant concentrations throughout the New Hampshire estuarine waters. All samples collected for the Gulfwatch monitoring program, from the Canadian provinces as well as the New England states involved, have been sent to the same laboratories for analysis. All of the samples have been analyzed at the same time in the same laboratories in an effort to reduce error and variability. This practice has ensured the consistency that was necessary to allow a region-wide assessment of the health of the Gulf. During the 2010 sampling season, mussels were collected at six sampling locations in New Hampshire and Maine (MECC, NHHS, NHDP, NHRH, NHPI and NHLH). Project Goals and Objectives The goal of this project was to provide data for two PREP indicators of estuarine condition: TOX1 and TOX3. These two indicators report on “Shellfish tissue concentrations relative to FDA standards” and “Trends in shellfish tissue contaminant concentrations”, respectively. Both of these indicators depend on data from the Gulfwatch Program. In particular, TOX3 requires annual data at benchmark sites to assess trends. In 2010, PREP supported the collection and analysis of tissue samples from benchmark mussel sites in Hampton-Seabrook Harbor and Dover Point

Shellfish Tissue Monitoring in Piscataqua Region Estuaries 2012

Originally conducted by a committee of Canadian and US governments and university scientists, Gulfwatch examined the effects of decades of development and industrialization on the water quality of the Gulf of Maine as it relates to human health primarily through assessing contaminant exposure of marine organisms from 1993 to 2010. The NH Gulfwatch Program continues these efforts by collecting blue mussels at two sites in the Great Bay Estuary and one in the Hampron-Seabrook Estuary, and analyzes the organisms’ tissue for potentially harmful levels and concentrations of toxins including heavy metals, chlorinated pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). During the 2012 sampling season, mussels were collected at three sampling locations in New Hampshire and Maine (MECC, NHHS and NHDP)