211 research outputs found
Evaluating Reclaimed Mines and Heavy Metal Soil Contamination
Arkansas has a rich history of lead and zinc mining. While there are still some active mines, many historical mines have been abandoned and/or reclaimed. Although most reclamation procedures result in the burial and containment of target minerals, accessory minerals and elements can be leached out of waste materials/tailings piles and include heavy metals (i.e., Pb, As, Cd). We aim to evaluate the soil and watershed of a few abandoned/reclaimed mines in Pope County, AR, for the presence of heavy metals/source minerals. Soil and stream sediment geochemistry will be conducted using a portable x-ray fluorescence analyzer. Field work and sampling plans will be developed to initially identify the presence of heavy metals in the immediate area, and then secondarily as to whether heavy metals are actively being transported in soil and stream sediments. Results from this study will help determine whether there is potential heavy metal contamination/leaching from these inactive mines
The Chronus Quantum (ChronusQ) Software Package
The Chronus Quantum (ChronusQ) software package is an open source (under the
GNU General Public License v2) software infrastructure which targets the
solution of challenging problems that arise in ab initio electronic structure
theory. Special emphasis is placed on the consistent treatment of time
dependence and spin in the electronic wave function, as well as the inclusion
of relativistic effects in said treatments. In addition, ChronusQ provides
support for the inclusion of uniform finite magnetic fields as external
perturbations through the use of gauge-including atomic orbitals (GIAO).
ChronusQ is a parallel electronic structure code written in modern C++ which
utilizes both message passing (MPI) and shared memory (OpenMP) parallelism. In
addition to the examination of the current state of code base itself, a
discussion regarding ongoing developments and developer contributions will also
be provided.Comment: 43 pages, 2 figure
Discovery and Identification of Dimethylsilanediol as a Contaminant in ISS Potable Water
In September of 2010, analysis of ISS potable water samples was undertaken to determine the contaminant responsible for a rise in total organic carbon (TOC). As analysis of the routine target list of organic compounds did not reveal the contaminant, efforts to look for unknown compounds was initiated, resulting in an unknown peak being discovered in the gas chromatography/mass spectrometry (GC/MS) analysis for glycols. A mass spectrum of the contaminant was then generated by concentrating one of the samples by evaporation and analyzing by GC/MS in full-scan mode. Although a computer match of the compound s identity could not be obtained with the instrument s database, a search with a more up to date mass spectral library yielded a good match with dimethylsilanediol (DMSD). Inductively Coupled Plasma/Mass Spectrometry (ICP/MS) analyses showed abnormally high silicon levels in the samples, confirming that the unknown contained silicon. DMSD was then synthesized to confirm the identification and provide a standard to develop a calibration curve. Further confirmation was provided by external Direct Analysis in Real Time (DART) GC/MS analysis. A preliminary GC/MS method was then developed and archived samples from various locations on ISS were analyzed to determine the extent of the contamination and provide data for troubleshooting. This paper describes these events in more detail as well as problems encountered in routine GC/MS analyses and the subsequent development of high performance liquid chromatography and LC/MS/MS methods for quantitation of DMSD
Discovery and Identification of Dimethylsilanediol as a Contaminant in ISS Potable Water
In September 2010, analysis of ISS potable water samples was undertaken to determine the contaminant(s) responsible for a rise of total organic carbon (TOC) in the Water Processor Assembly (WPA) product water. As analysis of the routine target list of organic compounds did not reveal the contaminant, efforts to look for unknown compounds were initiated, resulting in discovery of an unknown peak in the gas chromatography/mass spectrometry (GC/MS) analysis for glycols. A mass spectrum of the contaminant was then generated by concentrating one of the samples and analyzing it by GC/MS in full-scan mode. Although a computer match of the compound identity could not be obtained with the instrument database, a search with a more up-to-date mass spectral library yielded a good match with dimethylsilanediol (DMSD). Inductively coupled plasma/mass spectrometry (ICP/MS) analyses showed abnormally high silicon levels in the samples, confirming that the unknown compound(s) contained silicon. DMSD was then synthesized to confirm the identification and provide a standard to develop a calibration curve. Further confirmation was provided by external direct analysis in real time time of flight (DART TOF) mass spectrometry. To routinely test for DMSD in the future, a quantitative method was needed. A preliminary GC/MS method was developed and archived samples from various locations on ISS were analyzed to determine the extent of the contamination and provide data for troubleshooting. This paper describes these events in more detail as well as problems encountered in routine GC/MS analyses and the subsequent development of high performance liquid chromatography and LC/MS/MS methods for measuring DMSD
Picking and Choosing Among Phase I Trials
This article empirically examines how healthy volunteers evaluate and make sense of the risks of phase I clinical drug trials. This is an ethically important topic because healthy volunteers are exposed to risk but can gain no medical benefit from their trial participation. Based on in-depth qualitative interviews with 178 healthy volunteers enrolled in various clinical trials, we found that participants focus on myriad characteristics of clinical trials when assessing risk and making enrolment decisions. These factors include the short-term and long-term effects; required medical procedures; the type of trial, including its design, therapeutic area of investigation, and dosage of the drug; the amount of compensation; and trust in the research clinic. In making determinations about the study risks, participants rely on information provided during the consent process, their own and others’ experiences in clinical trials, and comparisons among studies. Our findings indicate that the informed consent process succeeds in communicating well about certain types of risk information while simultaneously creating lacunae that are problematically filled by participants through their collective experiences and assumptions about risk. We discuss the ethical implications of these findings and make recommendations for improving the consent process in healthy volunteer trials
Correction to: Picking and Choosing Among Phase I Trials
Correction to: "Picking and Choosing Among Phase I Trials
A review of the institutional landscape for dual-career hiring in higher education
Meeting the needs of dual-career academic couples has become an important part of university efforts to foster family-friendly workplaces. Many universities have developed formal or informal approaches to addressing dual-career issues, but variation across institutions has made it difficult to detect wider patterns or probe their implications. In this paper, we analyze the dual-career policies and materials (848 documents total) of all R1 institutions in the United States. As with studies from roughly two decades ago, we find deficiencies in institutional support and transparency. However, given reduced state revenues for institutions of higher education and a rise in precarious employment arrangements over the same time period, conditions for academic couples are arguably worse today. In order for universities to address these concerns and contribute meaningfully to broader forms of inclusion, we argue that there is a need for sustained funding commitments and infrastructural support for dual-career programs
Correction: A review of the institutional landscape for dual-career hiring in higher education
Correction to "A review of the institutional landscape for dual-career hiring in higher education
‘I'm still a hustler’: entrepreneurial responses to precarity by participants in phase I clinical trials
This paper questions the implications of entrepreneurial responses to conditions of employment precarity by ‘healthy volunteers’ in phase I clinical trials in the United States. Such individuals are typically serial participants who often identify as professional volunteers and seek out drug studies as their primary source of income. Drawing on extensive qualitative research, this paper illustrates how healthy volunteers selectively import the identity of ‘hustler’ from the street environment and reposition it as connoting a set of valuable creative skills that give them a competitive edge over other participants. An entrepreneurial ethos allows them to view personal sacrifice and exposure to potentially dangerous drugs as smart investments leading to financially stable futures. These discursive moves normalize extractive, and at times dehumanizing, labour relations that offload expenses and risks to workers
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