A Mid-Infrared Imaging Survey of Embedded Young Stellar Objects in the Rho Ophiuchi Cloud Core

Results of a comprehensive, new, ground-based mid-infrared imaging survey of the young stellar population of the Rho Ophiuchi cloud are presented. Data were acquired at the Palomar 5-m and at the Keck 10-m telescopes with the MIRLIN and LWS instruments, at 0.25 arcsec and 0.25 arcsec resolutions, respectively. Of 172 survey objects, 85 were detected. Among the 22 multiple systems observed, 15 were resolved and their individual component fluxes determined. A plot of the frequency distribution of the detected objects with SED spectral slope shows that YSOs spend ~400,000 yr in the Flat Spectrum phase, clearing out their remnant infall envelopes. Mid-infrared variability is found among a significant fraction of the surveyed objects, and is found to occur for all SED classes with optically thick disks. Large-amplitude near-infrared variability, also found for all SED classes with optically thick disks, seems to occur with somewhat higher frequency at the earlier evolutionary stages. Although a general trend of mid-infrared excess and NIR veiling exists proceeding through SED classes, with Class I objects generally exhibiting K-veilings > 1, Flat Spectrum objects with K-veilings > 0.58, and Class III objects with K-veilings =0, Class II objects exhibit the widest range of K-band veiling values, 0-4.5. However, the highly variable value of veiling that a single source can exhibit in any of the SED classes in which active disk accretion can take place is striking, and is direct observational evidence for highly time-variable accretion activity in disks. Finally, by comparing mid-infrared vs. near-infrared excesses in a subsample with well-determined effective temperatures and extinction values, disk clearing mechanisms are explored. The results are consistent with disk clearing proceeding from the inside-out.Comment: 18 pages + 5 tables + 7 figure

Occupational Injuries on Thoroughbred Horse Farms: A Description of Latino and Non-Latino Workers\u27 Experiences

Animal production is a dangerous industry and increasingly reliant on a Latino workforce. Within animal production, little is known about the risks or the occupational hazards of working on farms involved in various aspects of thoroughbred horse breeding. Extant research suggests that horse workers are at risk of musculoskeletal and respiratory symptoms, kicks, and other injuries. However, limited known research has examined the experiences of the industry\u27s workers, including immigrant workers, despite their prominence and increased vulnerability. Using data collected from thoroughbred farm representatives via a phone-administered survey, a 2-hour face-to-face semi-structured interview, and farm injury logs, this article identifies and describes types of injuries experienced by workers (N = 284) and their surrounding circumstances. Results indicate that general injuries and musculoskeletal strains, sprains, and tears account for a majority of injuries among workers on thoroughbred farms. Upper limbs and extremities are most frequently injured, while direct contact with the horse accounted for over half of all injuries. No differences in the diagnoses or distribution of injury were found by ethnicity; however, Latinos were more often struck by or trampled by a horse while non-Latinos were more often injured by an insect or plant. Implications and opportunities for future research are discussed

Centerscope

Centerscope, formerly Scope, was published by the Boston University Medical Center "to communicate the concern of the Medical Center for the development and maintenance of improved health care in contemporary society.

Lung Cancer Screening Practices in North Carolina CT Facilities

The burden of lung cancer in the United States is staggering, with more Americans dying from lung cancer than the next four most common cancers combined. With endorsement of lung cancer screening by the United States Preventive Services Task Force and reimbursement by the Centers for Medicare and Medicaid Services (CMS), the number screened for lung cancer with low-dose computed tomography (LDCT) is anticipated to rise in the near future

Bostonia: The Boston University Alumni Magazine. Volume 9

Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

Performance of digital screening mammography in a population-based cohort of black and white women

There is scarce information on whether digital screening mammography performance differs between black and white women

The Influence of Mammographic Technologists on Radiologists' Ability to Interpret Screening Mammograms in Community Practice

To determine whether the mammographic technologist has an effect on the radiologists’ interpretative performance of screening mammography in community practice

Do Mammographic Technologists Affect Radiologists’ Diagnostic Mammography Interpretative Performance?

The purpose of this study was to determine whether the technologist has an effect on the radiologists’ interpretative performance of diagnostic mammography

Integron-mediated Multidrug Resistance in a Global Collection of Nontyphoidal Salmonella enterica Isolates

Horizontal gene transfer and clonal expansion contribute substantially to the dissemination of resistant strain

Occurrence of cytomegalovirus hepatitis in liver transplant patients

The differential diagnosis of liver dysfunction after orthotopic liver transplantation can be difficult. Cytomegalovirus (CMV) hepatitis is one possibility. This report reviews our experience with 17 cases of pathologically proven CMV hepatitis following liver transplantation and demonstrates the need for percutaneous liver biopsies to establish the diagnosis. There were seven pediatric patients (ages 2–11 years, five males, two females) and ten adult patients (ages 17–53 years, eight males, two females). The most common symptoms were prolonged fever (15 patients, with a mean duration of 22 ± 5.5 days), elevation in total bilirubin (14 patients), and elevation in liver enzymes (15 patients); all symptoms were also found in rejection. Leukopenia and thrombocytopenia, reported to frequently occur with CMV infection, were found in only three and five patients, respectively. Twelve patients with the above symptoms underwent percutaneous biopsy on one or more occasions to differentiate CMV hepatitis from rejection. The diagnosis was made at retransplantation in five patients. CMV hepatitis followed treatment for acute rejection in 14 patients and occurred without additional immunosuppression in three patients. All patients were maintained on cyclosporine and prednisone. Acute rejection episodes were treated with a 5‐day tapering dose of steroids (17 courses in 12 patients), OKT3 monoclonal antibody [Ortho (4 patients)] antithymocyte globulin [Upjohn (2 patients)], and azathioprine (1 patient). CMV was isolated from urine (nine patients), blood (nine patients), throat (seven patients), lungs (two patients), and other organs (two patients). CMV was cultured from the liver biopsy specimens in five of the seven attempts in pediatric patients. When the diangosis was confirmed in the absence of rejection, immunosuppression was routinely lowered. When rejection occurred concomitantly with CMV hepatitis, therapy had to be individualized. Retrospectively, three patients treated for rejection were noted at retransplantation to have only CMV hepatitis, and all three paients died. A high index of suspicion and the judicioususe of liver bopsies is essential in order to differentiate CMV hepatitis from other causes of posttransplant liver dysfunction. Copyright © 1988 Wiley‐Liss, Inc., A Wiley Compan