Publications by authors named "Christopher J Bean"

Article Synopsis
  • SARS-CoV-2, the virus responsible for COVID-19, was identified in 2019 and has led to a significant global health crisis.
  • The study evaluated the effectiveness of various serological tests for detecting SARS-CoV-2 specific antibodies, including in-house ELISA and commercial assays, using samples from confirmed COVID-19 patients and a control group.
  • All tests showed high sensitivity (95.4-96.6%) and diagnostic accuracy, but the researchers emphasized the need for independent evaluations to enhance the interpretation of serological test results.
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Despite advances in seismology and computing, the ability to image subsurface volcanic environments is poor, limiting our understanding of the overall workings of volcanic systems. This is related to substantive structural heterogeneities which strongly scatters seismic waves obscuring the ballistic arrivals normally used in seismology for wave velocity determination. Here we address this constraint by, using a deep learning approach, a Fourier neural operator (FNO), to model and invert seismic signals in volcanic settings.

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Induced seismicity is one of the main factors that reduces societal acceptance of deep geothermal energy exploitation activities, and felt earthquakes are the main reason for closure of geothermal projects. Implementing innovative tools for real-time monitoring and forecasting of induced seismicity was one of the aims of the recently completed COSEISMIQ project. Within this project, a temporary seismic network was deployed in the Hengill geothermal region in Iceland, the location of the nation's two largest geothermal power plants.

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Women and girls with bleeding disorders experience abnormal and excessive bleeding that can negatively impact their overall health and quality of life. In this report, we provide an overview of the biology, types, clinical care, and state of the science related to bleeding disorders in girls and women and describe Centers for Disease Control and Prevention (CDC) activities related to (1) surveillance of bleeding disorders in women; (2) scientific review, research, and collaboration to inform health care gaps in identifying and caring for women with bleeding disorders; and (3) development of health promotion and education programs to bring awareness about bleeding disorders to both women and girls in the population at large and various health care providers who care for women. Findings generated from surveillance and research activities inform the development of new public health programs aimed at improving diagnostic and health care services and empowering women with bleeding disorders with the knowledge they need to navigate a complex health care system with the need for specialty care services.

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The propensity for dynamic earthquake triggering is thought to depend on the local stress state and amplitude of the stress perturbation. However, the nature of this dependency has not been confirmed within a single crustal volume. Here, we show that at Sierra Negra volcano, Galápagos Islands, the intensity of dynamically triggered earthquakes increased as inflation of a magma reservoir elevated the stress state.

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Introduction: Females may have haemophilia with the same factor VIII (FVIII) or factor IX (FIX) levels as affected males. Characterization of females with haemophilia would be useful for health care planning to meet their unique needs. Federally-funded haemophilia treatment centres (HTCs) in the United States contribute data on all individuals with bleeding disorders receiving care to the Population Profile (HTC PP) component of the Community Counts Public Health Surveillance of Bleeding Disorders project.

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Wind driven ocean wave-wave interactions produce continuous Earth vibrations at the seafloor called secondary microseisms. While the origin of associated Rayleigh waves is well understood, there is currently no quantified explanation for the existence of Love waves in the most energetic region of the microseism spectrum (3-10 s). Here, using terrestrial seismic arrays and 3D synthetic acoustic-elastic simulations combined with ocean wave hindcast data, we demonstrate that, observed from land, our general understanding of Rayleigh and Love wave microseism sources is significantly impacted by 3D propagation path effects.

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Recent large basaltic eruptions began after only minor surface uplift and seismicity, and resulted in caldera subsidence. In contrast, some eruptions at Galápagos Island volcanoes are preceded by prolonged, large amplitude uplift and elevated seismicity. These systems also display long-term intra-caldera uplift, or resurgence.

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This work describes the data used in the EPSL research article "Quantifying strong seismic propagation effects in the upper volcanic edifice using sensitivity kernels". The dataset is generated in order to investigate to what extent the seismic signals recorded on volcanoes are affected by near surface velocity structure. Data were calculated using the computational spectral elements scheme SPECFEM2D, where the wave propagation beneath Mount Etna volcano, Italy, was simulated in both homogeneous and heterogeneous models.

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Women and girls reported as "haemophilic females" may have complex genetic causes for their haemophilia phenotype. In addition, women and girls may have excessive bleeding requiring treatment simply because they are heterozygous for haemophilia alleles. While severe and moderate haemophilia are rare in females, 16% of patients with mild haemophilia A and almost one-quarter of those with mild haemophilia B seen in U.

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Study Objective: We provide an updated assessment of trends in sickle cell disease (SCD)-related mortality, a significant source of mortality in the United States among black persons, using 1979 to 2017 US mortality data.

Methods: SCD-related deaths were identified with International Classification of Diseases codes. Because SCD-related death is rare in other races, the analysis focused on black decedents.

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Problem/condition: Hemophilia is an X-linked genetic disorder that primarily affects males and results in deficiencies in blood-clotting proteins. Hemophilia A is a deficiency in factor VIII, and hemophilia B is a deficiency in factor IX. Approximately one in 5,000 males are born with hemophilia, and hemophilia A is about four times as common as hemophilia B.

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Glacier runoff and melt from volcanic and geothermal activity accumulates in glacier dammed lakes in glaciated areas around the world. These lakes eventually drain, creating hazardous subglacial floods that are usually only confirmed after they exit the glacier and reach local river systems, which can be many tens of kilometres from the flood source. Once in the river systems, they travel rapidly to populated areas.

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Objective: In the multicentre Haemoglobinopathy Blood Surveillance Project, to evaluate the seroprevalence of parvovirus B19 and DNA viral load in sickle cell disease (SCD).

Background: Although the epidemiology of parvovirus B19 seropositivity in SCD has been well documented, there are few studies that have assessed possible persistent parvovirus DNAemia and associated risk factors including blood transfusion.

Methods: A qualitative analysis of parvovirus B19 serology using ELISA and quantitative parvovirus B19 DNA by RT-PCR was performed in patients with SCD.

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Background: The National Birth Defects Prevention Study (NBDPS) is a multisite, population-based, case-control study of genetic and nongenetic risk factors for major structural birth defects. Eligible women had a pregnancy affected by a birth defect or a liveborn child without a birth defect between 1997 and 2011. They were invited to complete a telephone interview to collect pregnancy exposure data and were mailed buccal cell collection kits to collect specimens from themselves, their child (if living), and their child's father.

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Aim: The study objectives were to investigate the association between selected CYP2C9 and VKORC1 single nucleotide polymorphisms with serious bleeding or thrombotic risk, and to estimate mean daily maintenance dose of warfarin and international normalized ratio measurements among Blacks receiving warfarin anticoagulation.

Methods: We conducted a retrospective cohort study among 230 Black adults receiving warfarin for a minimum of three consecutive months with a confirmed date of first dosage.

Results: A lower mean daily maintenance dosage of warfarin was required to maintain an international normalized ratio measurement within the therapeutic range among Blacks with the VKORC1-1639G>A variant alleles ([G/A vs G/G, p = 0.

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Many of the world's largest volcanic eruptions are associated with geological rifting where major fractures open at the Earth's surface, yet fundamental controls on the near-surface response to the rifting process are lacking. New high resolution observations gleaned from seismometer data during the 2014 Bárðarbunga basaltic dyke intrusion in Iceland allow us unprecedented access to the associated graben formation process on both sub-second and micrometre scales. We find that what appears as quasi steady-state near-surface rifting on lower resolution GPS observation comprises discrete staccato-like deformation steps as the upper crust unzips through repetitive low magnitude (M < 0) failures on fracture patches estimated between 300 m and 1200 m in size.

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Crust at many divergent plate boundaries forms primarily by the injection of vertical sheet-like dykes, some tens of kilometres long. Previous models of rifting events indicate either lateral dyke growth away from a feeding source, with propagation rates decreasing as the dyke lengthens, or magma flowing vertically into dykes from an underlying source, with the role of topography on the evolution of lateral dykes not clear. Here we show how a recent segmented dyke intrusion in the Bárðarbunga volcanic system grew laterally for more than 45 kilometres at a variable rate, with topography influencing the direction of propagation.

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Background: Sickle cell disease (SCD) is an autosomal recessive genetic disorder, with persons heterozygous for the mutation said to have the sickle cell trait (SCT). Serious adverse effects are mainly limited to those with SCD, but the distinction between disease and trait is not always clear to the general population. We sought to determine the accuracy of self-reported SCD when compared to genetic confirmation.

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