118 research outputs found
Reconstruction of contaminant trends in a salt wedge estuary with sediment cores dated using a multiple proxy approach
The Taunton River is a partially mixed tidal estuary in southeastern Massachusetts (USA) which has received significant contaminant inputs, yet little information exists on the history of discharge and the subsequent fate of these contaminants. Three sediment cores taken along a transect were analyzed, reconstructing the spatial and temporal trends of pollution in the estuary. A combination of radiometric dating, contaminant markers, and storm layers from major hurricanes were used to establish age models and sedimentation rates. Age estimates obtained from the different dating methods compared well, establishing an accurate history of contaminant release to the estuary. Polycyclic aromatic hydrocarbons (PAHs) were present in one core at depths corresponding to the early 1860s, earlier than previously established dates of introduction. Temporal and spatial trends of Cr, Cu, Hg and Pb indicated multiple sources of varying input to the river. Polychlorinated biphenyls (PCBs) were present in each of the cores from the 1930s onward, with elevated levels still present in surficial sediments at several sites. A unique organic compound, Topanol, which was produced locally was used as a tracer to track contaminant transport in the river. Tracer data indicates that contaminants are still being transported and deposited to surficial sediments at high concentrations well after their discharge. This reconstruction demonstrates the utility of using multiple dating proxies where often the sole use of radiometric dating techniques is not an option and provides insights into the fate of contaminants discharged decades ago but continue to represent environmental risks
Time trends and trophic transfer of polybrominated diphenylethers (PBDEs) in Antarctic biota
Polybrominated diphenyl ethers (PBDEs) are “emerged” contaminants that were produced and used as flame retardants in numerous consumer and industrial applications for decades until banned. They remain ubiquitously present in the environment today. Here, a unique set of \u3e200 biotic samples from the Antarctic was analyzed for PBDEs, including phytoplankton, krill, fish, and fur seal milk, spanning several sampling seasons over 14 years. PBDE-47 and -99 were the dominant congeners determined in all samples, constituting \u3e60% of total PBDEs. A temporal trend was observed for ∑7PBDE concentrations in fur seal milk, where concentrations significantly increased (R2 = 0.57, p \u3c 0.05) over time (2000–2014). Results for krill and phytoplankton also suggested increasing PBDE concentrations over time. Trends of PBDEs in fur seal milk of individual seals sampled 1 or more years apart showed no clear temporal trends. Overall, there was no indication of PBDEs decreasing in Antarctic biota yet, whereas numerous studies have reported decreasing trends in the northern hemisphere. Similar PBDE concentrations in perinatal versus nonperinatal milk implied the importance of local PBDE sources for bioaccumulation. These results indicate the need for continued assessment of contaminant trends, such as PBDEs, and their replacements, in Antarctica
Legacy and Novel Per- and Polyfluoroalkyl Substances in Juvenile Seabirds from the U.S. Atlantic Coast
Per- and polyfluoroalkyl substances (PFAS) are anthropogenic, globally distributed chemicals. Legacy PFAS, including perfluorooctane sulfonate (PFOS), have been regularly detected in marine fauna but little is known about their current levels or the presence of novel PFAS in seabirds. We measured 36 emerging and legacy PFAS in livers from 31 juvenile seabirds from Massachusetts Bay, Narragansett Bay, and the Cape Fear River Estuary (CFRE), United States. PFOS was the major legacy perfluoroalkyl acid present, making up 58% of concentrations observed across all habitats (range: 11–280 ng/g). Novel PFAS were confirmed in chicks hatched downstream of a fluoropolymer production site in the CFRE: a perfluorinated ether sulfonic acid (Nafion byproduct 2; range: 1–110 ng/g) and two perfluorinated ether carboxylic acids (PFO4DA and PFO5DoDA; PFO5DoDA range: 5–30 ng/g). PFOS was inversely associated with phospholipid content in livers from CFRE and Massachusetts Bay individuals, while δ 13C, an indicator of marine versus terrestrial foraging, was positively correlated with some long-chain PFAS in CFRE chick livers. There is also an indication that seabird phospholipid dynamics are negatively impacted by PFAS, which should be further explored given the importance of lipids for seabirds
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Safety, pharmacokinetics, and preliminary assessment of efficacy of mecasermin (recombinant human IGF-1) for the treatment of Rett syndrome
Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder mainly affecting females and is associated with mutations in MECP2, the gene encoding methyl CpG-binding protein 2. Mouse models suggest that recombinant human insulin-like growth factor 1 (IGF-1) (rhIGF1) (mecasermin) may improve many clinical features. We evaluated the safety, tolerability, and pharmacokinetic profiles of IGF-1 in 12 girls with MECP2 mutations (9 with RTT). In addition, we performed a preliminary assessment of efficacy using automated cardiorespiratory measures, EEG, a set of RTT-oriented clinical assessments, and two standardized behavioral questionnaires. This phase 1 trial included a 4-wk multiple ascending dose (MAD) (40–120 μg/kg twice daily) period and a 20-wk open-label extension (OLE) at the maximum dose. Twelve subjects completed the MAD and 10 the entire study, without evidence of hypoglycemia or serious adverse events. Mecasermin reached the CNS compartment as evidenced by the increase in cerebrospinal fluid IGF-1 levels at the end of the MAD. The drug followed nonlinear kinetics, with greater distribution in the peripheral compartment. Cardiorespiratory measures showed that apnea improved during the OLE. Some neurobehavioral parameters, specifically measures of anxiety and mood also improved during the OLE. These improvements in mood and anxiety scores were supported by reversal of right frontal alpha band asymmetry on EEG, an index of anxiety and depression. Our data indicate that IGF-1 is safe and well tolerated in girls with RTT and, as demonstrated in preclinical studies, ameliorates certain breathing and behavioral abnormalities
Identification of common variants influencing risk of the tauopathy progressive supranuclear palsy
CurePSP Foundation, the Peebler PSP Research Foundation, and National Institutes on Health (NIH) grants R37 AG 11762, R01 PAS-03-092, P50 NS72187, P01 AG17216 [National Institute on Aging(NIA)/NIH], MH057881 and MH077930 [National Institute of Mental Health (NIMH)]. Work was also supported in part by the NIA Intramural Research Program, the German National Genome Research Network (01GS08136-4) and the Deutsche Forschungsgemeinschaft (HO 2402/6-1), Prinses Beatrix Fonds (JCvS, 01–0128), the Reta Lila Weston Trust and the UK Medical Research Council (RdS: G0501560). The Newcastle Brain Tissue Resource provided tissue and is funded in part by a grant from the UK Medical Research Council (G0400074), by the Newcastle NIHR Biomedical Research Centre in Ageing and Age Related Diseases to the Newcastle upon Tyne Hospitals NHS Foundation Trust, and by a grant from the Alzheimer’s Society and Alzheimer’s Research Trust as part of the Brains for
Dementia Resarch Project. We acknowledge the contribution of many tissue samples from the Harvard Brain Tissue Resource Center. We also acknowledge the 'Human Genetic Bank of Patients affected by Parkinson Disease and parkinsonism' (http://www.parkinson.it/dnabank.html) of the Telethon Genetic Biobank Network, supported by TELETHON Italy (project n. GTB07001) and by Fondazione Grigioni per il Morbo di Parkinson. The University of Toronto sample collection was supported by grants from Wellcome Trust, Howard Hughes Medical Institute, and the Canadian Institute of Health Research. Brain-Net-Germany is supported by BMBF (01GI0505). RdS, AJL and JAH are funded by the Reta Lila Weston Trust and the PSP (Europe) Association. RdS is funded by the UK Medical Research Council (Grant G0501560) and Cure PSP+. ZKW is partially supported by the NIH/NINDS 1RC2NS070276, NS057567, P50NS072187, Mayo Clinic Florida (MCF)Research Committee CR programs (MCF #90052030 and MCF #90052030), and the gift from Carl Edward Bolch, Jr., and Susan Bass Bolch (MCF #90052031/PAU #90052). The Mayo Clinic College of Medicine would like to acknowledge Matt Baker, Richard Crook, Mariely DeJesus-Hernandez and Nicola Rutherford for their preparation of samples. PP was supported by a grant from the Government of Navarra ("Ayudas para la Realización de Proyectos de Investigación" 2006–2007) and acknowledges the "Iberian Atypical Parkinsonism Study Group Researchers", i.e. Maria A. Pastor, Maria R. Luquin, Mario Riverol, Jose A. Obeso and Maria C Rodriguez-Oroz (Department of Neurology, Clínica Universitaria de Navarra, University of Navarra, Pamplona, Spain), Marta Blazquez (Neurology Department, Hospital Universitario Central de Asturias, Oviedo, Spain), Adolfo Lopez de Munain, Begoña Indakoetxea, Javier Olaskoaga, Javier Ruiz, José Félix Martí Massó (Servicio de Neurología, Hospital Donostia, San Sebastián, Spain), Victoria Alvarez (Genetics Department, Hospital Universitario Central de Asturias, Oviedo, Spain), Teresa Tuñon (Banco de Tejidos Neurologicos, CIBERNED, Hospital de Navarra, Navarra, Spain), Fermin Moreno (Servicio de Neurología, Hospital Ntra. Sra. de la Antigua, Zumarraga, Gipuzkoa, Spain), Ainhoa Alzualde (Neurogenétics Department, Hospital Donostia, San Sebastián, Spain)
Building a Quantum Engineering Undergraduate Program
Contribution: A roadmap is provided for building a quantum engineering education program to satisfy U.S. national and international workforce needs.
Background: The rapidly growing quantum information science and engineering (QISE) industry will require both quantum-aware and quantum-proficient engineers at the bachelor\u27s level.
Research Question: What is the best way to provide a flexible framework that can be tailored for the full academic ecosystem?
Methodology: A workshop of 480 QISE researchers from across academia, government, industry, and national laboratories was convened to draw on best practices; representative authors developed this roadmap.
Findings: 1) For quantum-aware engineers, design of a first quantum engineering course, accessible to all STEM students, is described; 2) for the education and training of quantum-proficient engineers, both a quantum engineering minor accessible to all STEM majors, and a quantum track directly integrated into individual engineering majors are detailed, requiring only three to four newly developed courses complementing existing STEM classes; 3) a conceptual QISE course for implementation at any postsecondary institution, including community colleges and military schools, is delineated; 4) QISE presents extraordinary opportunities to work toward rectifying issues of inclusivity and equity that continue to be pervasive within engineering. A plan to do so is presented, as well as how quantum engineering education offers an excellent set of education research opportunities; and 5) a hands-on training plan on quantum hardware is outlined, a key component of any quantum engineering program, with a variety of technologies, including optics, atoms and ions, cryogenic and solid-state technologies, nanofabrication, and control and readout electronics
Building a Quantum Engineering Undergraduate Program
The rapidly growing quantum information science and engineering (QISE)
industry will require both quantum-aware and quantum-proficient engineers at
the bachelor's level. We provide a roadmap for building a quantum engineering
education program to satisfy this need. For quantum-aware engineers, we
describe how to design a first quantum engineering course accessible to all
STEM students. For the education and training of quantum-proficient engineers,
we detail both a quantum engineering minor accessible to all STEM majors, and a
quantum track directly integrated into individual engineering majors. We
propose that such programs typically require only three or four newly developed
courses that complement existing engineering and science classes available on
most larger campuses. We describe a conceptual quantum information science
course for implementation at any post-secondary institution, including
community colleges and military schools. QISE presents extraordinary
opportunities to work towards rectifying issues of inclusivity and equity that
continue to be pervasive within engineering. We present a plan to do so and
describe how quantum engineering education presents an excellent set of
education research opportunities. Finally, we outline a hands-on training plan
on quantum hardware, a key component of any quantum engineering program, with a
variety of technologies including optics, atoms and ions, cryogenic and
solid-state technologies, nanofabrication, and control and readout electronics.
Our recommendations provide a flexible framework that can be tailored for
academic institutions ranging from teaching and undergraduate-focused two- and
four-year colleges to research-intensive universities.Comment: 25 pages, 2 figure
Novel Plasmids and Resistance Phenotypes in Yersinia pestis: Unique Plasmid Inventory of Strain Java 9 Mediates High Levels of Arsenic Resistance
Growing evidence suggests that the plasmid repertoire of Yersinia pestis is not restricted to the three classical virulence plasmids. The Java 9 strain of Y. pestis is a biovar Orientalis isolate obtained from a rat in Indonesia. Although it lacks the Y. pestis-specific plasmid pMT, which encodes the F1 capsule, it retains virulence in mouse and non-human primate animal models. While comparing diverse Y. pestis strains using subtractive hybridization, we identified sequences in Java 9 that were homologous to a Y. enterocolitica strain carrying the transposon Tn2502, which is known to encode arsenic resistance. Here we demonstrate that Java 9 exhibits high levels of arsenic and arsenite resistance mediated by a novel promiscuous class II transposon, named Tn2503. Arsenic resistance was self-transmissible from Java 9 to other Y. pestis strains via conjugation. Genomic analysis of the atypical plasmid inventory of Java 9 identified pCD and pPCP plasmids of atypical size and two previously uncharacterized cryptic plasmids. Unlike the Tn2502-mediated arsenic resistance encoded on the Y. enterocolitica virulence plasmid; the resistance loci in Java 9 are found on all four indigenous plasmids, including the two novel cryptic plasmids. This unique mobilome introduces more than 105 genes into the species gene pool. The majority of these are encoded by the two entirely novel self-transmissible plasmids, which show partial homology and synteny to other enterics. In contrast to the reductive evolution in Y. pestis, this study underlines the major impact of a dynamic mobilome and lateral acquisition in the genome evolution of the plague bacterium
Impact of Firm Heterogeneity on Direct and Spillover Effects of FDI: Micro Evidence from Ten Transition Countries
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