449 research outputs found
Progressive Star Bursts and High Velocities in the Infrared Luminous, Colliding Galaxy Arp 118
In this paper we demonstrate for the first time the connection between the
spatial and temporal progression of star formation and the changing locations
of the very dense regions in the gas of a massive disk galaxy (NGC 1144) in the
aftermath of its collision with a massive elliptical (NGC 1143). These two
galaxies form the combined object Arp 118, a collisional ring galaxy system.
The results of 3D, time-dependent, numerical simulations of the behavior of the
gas, stars, and dark matter of a disk galaxy and the stars and dark matter in
an elliptical during a collision are compared with multiwavelength observations
of Arp 118. The collision that took place approximately 22 Myr ago generated a
strong, non-linear density wave in the stars and gas in the disk of NGC 1144,
causing the gas to became clumped on a large scale. This wave produced a series
of superstarclusters along arcs and rings that emanate from the central point
of impact in the disk. The locations of these star forming regions match those
of the regions of increased gas density predicted the time sequence of models.
The models also predict the large velocity gradients observed across the disk
of NGC 1144. These are due to the rapid radial outflow of gas coupled to large
azimuthal velocities in the expanding ring, caused by the impact of the massive
intruder.Comment: 12 pages in document, and 8 figures (figures are separate from the
document's file); Submitted to Astrophysical Journal Letter
Salmonella enterica Serotype Uganda Infection in New York City and Chicago1
Outbreaks associated with distinct strains of Salmonella enterica serotype Uganda, a rare serotype, occurred in New York City and Chicago during the summer of 2001. Both outbreaks were linked to eating ready-to-eat pork products. This serotype may emerge as a more frequent cause of human infections
Molecular Epidemiology of Adenovirus Type 7 in the United States, 1966â20001
Genetic variation among 166 isolates of human adenovirus 7 (Ad7) obtained from 1966 to 2000 from the United States and Eastern Ontario, Canada, was determined by genome restriction analysis. Most (65%) isolates were identified as Ad7b. Two genome types previously undocumented in North America were also identified: Ad7d2 (28%), which first appeared in 1993 and was later identified throughout the Midwest and Northeast of the United States and in Canada; and Ad7h (2%), which was identified only in the U.S. Southwest in 1998 and 2000. Since 1996, Ad7d2 has been responsible for several civilian outbreaks of Ad7 disease and was the primary cause of a large outbreak of respiratory illness at a military recruit training center. The appearance of Ad7d2 and Ad7h in North America represents recent introduction of these viruses from previously geographically restricted areas and may herald a shift in predominant genome type circulating in the United States
Respiratory viral surveillance of healthcare personnel and patients at an adult long-term care facility
We conducted active surveillance of acute respiratory viral infections (ARIs) among residents and healthcare personnel (HCP) at a long-term care facility during the 2015-2016 respiratory illness season. ARIs were observed among both HCP and patients, highlighting the importance of including HCP in surveillance programs
Marine Microalgae: Climate, Energy, and Food Security From the Sea
Climate, energy, and food security are three of the greatest challenges society faces this century. Solutions for mitigating the effects of climate change often conflict with solutions for ensuring societyâs future energy and food requirements. For example, BioEnergy with Carbon Capture and Storage (BECCS) has been proposed as an important method for achieving negative CO2 emissions later this century while simultaneously producing renewable energy on a global scale. However, BECCS has many negative environmental consequences for land, nutrient, and water use as well as biodiversity and food production. In contrast, large-scale industrial cultivation of marine microalgae can provide society with a more environmentally favorable approach for meeting the climate goals agreed to at the 2015 Paris Climate Conference, producing the liquid hydrocarbon fuels required by the global transportation sector, and supplying much of the protein necessary to feed a global population approaching 10 billion people
Timing of respiratory syncytial virus and influenza epidemic activity in five regions of Argentina, 2007-2016
Fil: Baumeister, Elsa. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Departamento de VirologĂa. Servicio de Virosis Respiratoria; Argentina.Fil: Duque, Jazmin. Influenza Division, National Center for Immunization and Respiratory Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Fil: Varela, Teresa. Sistema Nacional de Vigilancia por Laboratorio, Sistema Nacional de Vigilancia de la Salud, Ministerio de Salud de la NaciĂłn, Buenos Aires; Argentina.Fil: Palekar, Rakhee. Influenza Division, National Center for Immunization and Respiratory Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Fil: Couto, Paula. Pan American Health Organization, Washington, District of Columbia; Estados Unidos.Fil: Savy, Vilma L. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Departamento de VirologĂa. Servicio de Virosis Respiratoria; Argentina.Fil: Giovacchini, Carlos. Pan American Health Organization, Washington, District of Columbia; Estados Unidos.Fil: Haynes, Amber K. Division of Viral Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Fil: Rha, Brian. Division of Viral Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Fil: Arriola, Carmen S. Influenza Division, National Center for Immunization and Respiratory Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Fil: Gerber, Susan I. Division of Viral Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Fil: Azziz-Baumgartner, Eduardo. Influenza Division, National Center for Immunization and Respiratory Diseases, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia; Estados Unidos.Within-country differences in the timing of RSV and influenza epidemics have not been assessed in Argentina, the eighth largest country in the world by area
Respiratory syncytial virus seasonality in three epidemiological zones of Kenya
Understanding respiratory syncytial virus (RSV) circulation patterns is necessary to guide the timing of limitedâduration interventions such as vaccines. We describe RSV circulation over multiple seasons in three distinct counties of Kenya during 2006â2018. Kilifi and Siaya counties each had consistent but distinct RSV seasonality, lasting on average 18â22 weeks. Based on data from available years, RSV did not have a clear pattern of circulation in Nairobi. This information can help guide the timing of vaccines and immunoprophylaxis products that are under development
Influenza and respiratory syncytial virus in infants study (IRIS) of hospitalized and non-ill infants aged <1 year in four countries: study design and methods
Abstract
Background
This multi-country prospective study of infants aged <1Â year aims to assess the frequency of influenza virus and respiratory syncytial virus (RSV) infections associated with hospitalizations, to describe clinical features and antibody response to infection, and to examine predictors of very severe disease requiring intensive care.
Methods/Design
We are enrolling a hospital-based cohort and a sample of non-ill infants in four countries (Albania, Jordan, Nicaragua, and the Philippines) using a common protocol. We are currently starting year 2 of a 2- to 3-year study and will enroll approximately 3,000 infants hospitalized for any acute illness (respiratory or non-respiratory) during periods of local influenza and/or RSV circulation. After informed consent and within 24 h of admission, we collect blood and respiratory specimens and conduct an interview to assess socio-demographic characteristics, medical history, and symptoms of acute illness (onset â€10 days). Vital signs, interventions, and medications are documented daily through medical record abstraction. A follow-up health assessment and collection of convalescent blood occurs 3-5 weeks after enrollment. Influenza and RSV infection is confirmed by singleplex real time reverse transcriptase polymerase chain reaction (rRT-PCR) assays. Serologic conversion will be assessed comparing acute and convalescent sera using hemagglutination inhibition assay for influenza antibodies and enzyme-linked immunosorbent assay (ELISA) for RSV. Concurrent with hospital-based enrollment, respiratory specimens are also being collected (and tested by rRT-PCR) from approximately 1,400 non-ill infants aged <1 year during routine medical or preventive care.
Discussion
The Influenza and RSV in Infants Study (IRIS) promises to expand our knowledge of the frequency, clinical features, and antibody profiles of serious influenza and RSV disease among infants aged <1Â year, quantify the proportion of infections that may be missed by traditional surveillance, and inform decisions about the potential value of existing and new vaccines and other prevention and treatment strategies.https://deepblue.lib.umich.edu/bitstream/2027.42/136185/1/12879_2017_Article_2299.pd
Multihospital Outbreak of a Middle East Respiratory Syndrome Coronavirus Deletion Variant, Jordan: A Molecular, Serologic, and Epidemiologic Investigation
Background
An outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) in Jordan in 2015 involved a variant virus that acquired distinctive deletions in the accessory open reading frames. We conducted a molecular and seroepidemiologic investigation to describe the deletion variantâs transmission patterns and epidemiology.
Methods
We reviewed epidemiologic and medical chart data and analyzed viral genome sequences from respiratory specimens of MERS-CoV cases. In early 2016, sera and standardized interviews were obtained from MERS-CoV cases and their contacts. Sera were evaluated by nucleocapsid and spike protein enzyme immunoassays and microneutralization.
Results
Among 16 cases, 11 (69%) had health care exposure and 5 (31%) were relatives of a known case; 13 (81%) were symptomatic, and 7 (44%) died. Genome sequencing of MERS-CoV from 13 cases revealed 3 transmissible deletions associated with clinical illness during the outbreak. Deletion variant sequences were epidemiologically clustered and linked to a common transmission chain. Interviews and sera were collected from 2 surviving cases, 23 household contacts, and 278 health care contacts; 1 (50%) case, 2 (9%) household contacts, and 3 (1%) health care contacts tested seropositive.
Conclusions
The MERS-CoV deletion variants retained human-to-human transmissibility and caused clinical illness in infected persons despite accumulated mutations. Serology suggested limited transmission beyond that detected during the initial outbreak investigation
Influenza and respiratory syncytial virus in infants study (IRIS) of hospitalized and non-ill infants aged <1 year in four countries: study design and methods
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