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1.
Science ; 358(6370): 1565-1570, 2017 12 22.
Article in English | MEDLINE | ID: mdl-29038371

ABSTRACT

With the first direct detection of merging black holes in 2015, the era of gravitational wave (GW) astrophysics began. A complete picture of compact object mergers, however, requires the detection of an electromagnetic (EM) counterpart. We report ultraviolet (UV) and x-ray observations by Swift and the Nuclear Spectroscopic Telescope Array of the EM counterpart of the binary neutron star merger GW170817. The bright, rapidly fading UV emission indicates a high mass (≈0.03 solar masses) wind-driven outflow with moderate electron fraction (Ye ≈ 0.27). Combined with the x-ray limits, we favor an observer viewing angle of ≈30° away from the orbital rotation axis, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultrarelativistic, highly collimated ejecta (a γ-ray burst afterglow).

2.
Science ; 343(6166): 48-51, 2014 Jan 03.
Article in English | MEDLINE | ID: mdl-24263134

ABSTRACT

Long-duration gamma-ray bursts (GRBs) are an extremely rare outcome of the collapse of massive stars and are typically found in the distant universe. Because of its intrinsic luminosity (L ~ 3 × 10(53) ergs per second) and its relative proximity (z = 0.34), GRB 130427A reached the highest fluence observed in the γ-ray band. Here, we present a comprehensive multiwavelength view of GRB 130427A with Swift, the 2-meter Liverpool and Faulkes telescopes, and by other ground-based facilities, highlighting the evolution of the burst emission from the prompt to the afterglow phase. The properties of GRB 130427A are similar to those of the most luminous, high-redshift GRBs, suggesting that a common central engine is responsible for producing GRBs in both the contemporary and the early universe and over the full range of GRB isotropic energies.

3.
Nature ; 480(7375): 72-4, 2011 Nov 30.
Article in English | MEDLINE | ID: mdl-22129726

ABSTRACT

Long γ-ray bursts (GRBs) are the most dramatic examples of massive stellar deaths, often associated with supernovae. They release ultra-relativistic jets, which produce non-thermal emission through synchrotron radiation as they interact with the surrounding medium. Here we report observations of the unusual GRB 101225A. Its γ-ray emission was exceptionally long-lived and was followed by a bright X-ray transient with a hot thermal component and an unusual optical counterpart. During the first 10 days, the optical emission evolved as an expanding, cooling black body, after which an additional component, consistent with a faint supernova, emerged. We estimate its redshift to be z = 0.33 by fitting the spectral-energy distribution and light curve of the optical emission with a GRB-supernova template. Deep optical observations may have revealed a faint, unresolved host galaxy. Our proposed progenitor is a merger of a helium star with a neutron star that underwent a common envelope phase, expelling its hydrogen envelope. The resulting explosion created a GRB-like jet which became thermalized by interacting with the dense, previously ejected material, thus creating the observed black body, until finally the emission from the supernova dominated. An alternative explanation is a minor body falling onto a neutron star in the Galaxy.

4.
Nature ; 455(7210): 183-8, 2008 Sep 11.
Article in English | MEDLINE | ID: mdl-18784718

ABSTRACT

Long-duration gamma-ray bursts (GRBs) release copious amounts of energy across the entire electromagnetic spectrum, and so provide a window into the process of black hole formation from the collapse of massive stars. Previous early optical observations of even the most exceptional GRBs (990123 and 030329) lacked both the temporal resolution to probe the optical flash in detail and the accuracy needed to trace the transition from the prompt emission within the outflow to external shocks caused by interaction with the progenitor environment. Here we report observations of the extraordinarily bright prompt optical and gamma-ray emission of GRB 080319B that provide diagnostics within seconds of its formation, followed by broadband observations of the afterglow decay that continued for weeks. We show that the prompt emission stems from a single physical region, implying an extremely relativistic outflow that propagates within the narrow inner core of a two-component jet.

5.
Poult Sci ; 85(11): 1969-74, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17032831

ABSTRACT

Spontaneously occurring benign uterine leiomyomas (fibroids) are the most common tumors of reproductive-age women. It is estimated that more than 70% of all women will develop uterine fibroids, and the presence of these tumors is a primary cause of hysterectomies. Research into the causes and treatment of uterine fibroids is hampered by a lack of reliable animal models for the disease. Leiomyomas that appear to be outwardly similar to human uterine fibroid tumors are known to occur on the oviducts of laying hens over 2 yr of age. The objective of this study was to characterize these tumors and compare them to human uterine fibroids to determine the suitability of the aging hen as a model system for the study of the disease. In this study, hens at 5 yr of age were examined for the presence of oviduct-associated fibroid tumors. Tumors were found attached to the internal surface of the oviduct, embedded in the oviduct wall, or attached to the exterior of the magnum and isthmus. Tumor and normal oviduct samples were frozen or fixed in formalin for histological analyses or immunohistochemistry for estrogen and progesterone receptors, proliferating cell nuclear antigen and Bcl-2 protein expression. Human uterine fibroid samples were acquired and evaluated compared with hen oviduct fibroids. The results indicate that laying hen fibroid tumors are similar to human fibroid tumors with respect to estrogen and progesterone receptors, localized cellular proliferation, and expression of the Bcl-2 protein.


Subject(s)
Genital Neoplasms, Female/veterinary , Leiomyoma/veterinary , Oviducts , Poultry Diseases/pathology , Age Factors , Animals , Biomarkers, Tumor , Chickens , Disease Models, Animal , Female , Genital Neoplasms, Female/epidemiology , Genital Neoplasms, Female/pathology , Immunohistochemistry/veterinary , Leiomyoma/epidemiology , Leiomyoma/pathology , Oviducts/pathology , Poultry Diseases/epidemiology , Proto-Oncogene Proteins c-bcl-2/analysis , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis
7.
J Pediatr Surg ; 32(10): 1482-4, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9349776

ABSTRACT

A boy who had simple syndactyly involving the third web space of the left hand presented for elective syndactyly repair. Circumcision had been delayed because of neonatal medical problems. Elective syndactyly repair and circumcision were performed in one operation at age 9 months. Penile foreskin was used as a full-thickness skin graft for the syndactyly repair. The foreskin provided a functional syndactyly repair with good aesthetic characteristics. This obviated the need for two separate operations and for an additional skin graft donor site. To our knowledge, this is the first reported case in which foreskin was used for the repair of syndactyly. In boys with syndactyly, the authors advocate that parents be informed of this reconstructive option. Should the parents consider it to be suitable, then elective circumcision should be delayed until the time of syndactyly repair so that foreskin may be used for the syndactyly repair.


Subject(s)
Circumcision, Male , Hand Deformities, Congenital/surgery , Penis/surgery , Skin Transplantation , Syndactyly/surgery , Humans , Infant , Male
8.
Hand Clin ; 12(4): 705-18, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8953290

ABSTRACT

"Thoracic outlet syndrome" is a term ascribed to a complex clinical entity encompassing complicated neurovascular signs, symptoms and pathology of the upper extremity. Controversies exist concerning its causes, diagnosis, and treatment despite years of intense study of hundreds of patients. Although there is no universal agreement on the diagnostic and treatment modalities to be applied to each patient, general guidelines have emerged that can aid hand surgeons in recognizing and evaluating these potentially difficult patients. A review of the anatomy, causes, clinical presentations, diagnostic tests, and treatment options available for thoracic outlet syndrome is presented, followed by an illustrative case.


Subject(s)
Thoracic Outlet Syndrome , Adult , Female , Humans , Thoracic Outlet Syndrome/diagnosis , Thoracic Outlet Syndrome/etiology , Thoracic Outlet Syndrome/therapy
9.
Public Health Nurs ; 13(2): 120-7, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8936245

ABSTRACT

An urban shelter in Charleston, South Carolina developed and began a tuberculosis (TB) prevention and control plan that addressed the priorities recommended by the Centers for Disease Control and Prevention. After an increase in TB in the shelter in 1992, the local health department, the homeless clinic nurse practitioners, and Medical University of South Carolina College of Nursing faculty and students collaborated with the shelter staff to provide initial mass screenings for contact investigation. They also developed and implemented new policies and procedures for an ongoing TB prevention and control program. The new policies required that guests obtain screening for TB within 7 days of arrival at the shelter and every 6 months thereafter. Also, a public health nurse began providing directly observed therapy twice weekly at the shelter. Of the initial 22 persons who started TB preventive therapy in 1993, 17 (77%) completed therapy. The clinic nurse practitioners, nursing students, and public health nurses had important and defined roles in the mass-screening process, case identification and treatment, policy development and implementation, health education, and establishing methods of communication between the shelter, clinic, and health department. An ongoing health care community collaborative effort may successfully reduce tuberculosis disease in a homeless shelter population.


Subject(s)
Community Networks , Ill-Housed Persons , Tuberculosis, Pulmonary/prevention & control , Communication , Female , Health Education , Humans , Male , Mass Screening , South Carolina , Students, Nursing , Urban Population
11.
13.
Br J Obstet Gynaecol ; 102(12): 1019, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8652478
14.
Poult Sci ; 73(1): 186-93, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8165164

ABSTRACT

The purpose of this study was to measure plasma corticosterone and thyroid hormone concentrations in broilers exposed to various photoschedules. Day-old male broilers were placed on litter floors in light-controlled chambers. Four chambers were randomly assigned to each of four light treatments: 1) 23 h light (L):1 h dark (D) from 1 to 56 d of age (designated extended, E); 2) 1L:3D from 1 to 56 d (intermittent, I); 3) 6L:18D from 1 to 14 d and 1L:3D from 15 to 56 d (brief-I, BI); and 4) 6L:18D from 1 to 14 d and 23L:1D from 15 to 56 d (brief-E, BE). Blood samples were collected 0, 4, and 20 h after lights-on (1200 h) at 13, 41, and 55 d of age. Corticosterone concentration did not differ among light treatments or collection times and was decreased at 41 d compared with 13 d (.65 vs 2.11 ng/mL). Triiodothyronine (T3) increased and thyroxine (T4) decreased with age. At 13 d, there were light treatment by sampling time interactions for T3 and T4. Plasma T3 was elevated in Treatments BI (3.11 ng/mL) and BE (3.40 ng/mL) compared with Treatments E (2.39 ng/mL) and I (2.30 ng/mL) at 0 h; the former two treatments showed decreased T3 concentrations at 4 and 20 h compared with 0 h. Plasma T4 showed reciprocal changes to T3. There were no differences in T3 or T4 for light treatments or sampling times at 41 and 55 d.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Chickens/blood , Corticosterone/blood , Photoperiod , Thyroxine/blood , Triiodothyronine/blood , Animals , Male , Random Allocation
18.
Poult Sci ; 70(7): 1602-9, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1886871

ABSTRACT

The purpose of the present study was to examine the interaction of constant photoschedules and genetic background on performance of male broiler breeders. Day-old cockerels from two BW strains were placed on litter floors in light-controlled chambers. Light treatments (LT) (60 lx) consisted of 2, 4, 8, 16, and 24 h light/day. At 9 wk of age, birds were individually caged and evaluated biweekly for semen production. Venous blood samples were collected at 16, 32, 48, and 64 wk of age. Data for testes weight, histology, and morphometry were obtained at 64 wk. Age at first semen production showed a cubic response in the levels of LT with earliest semen production from 4 and 8 h light (187.0 and 188.2 days, respectively). The BW was linear in the levels of LT within week; average BW was generally greater for birds on short LT than for birds on longer LT. Semen concentration was also linear in the levels of LT within week; increased semen concentration occurred with short LT. Changes in semen weight and spermatozoa count per ejaculate across the levels of LT differed for strain. A larger percentage of males produced semen in the less than or equal to 8 h LT than in the 16 or 24 h LT. Plasma testosterone was lower at 16 wk compared with later ages, and a positive linear relationship existed between testosterone level and hours of light. There was a cubic LT effect for testes weight per BW with larger values for less than or equal to 8 h LT compared with 16 or 24 h LT.


Subject(s)
Chickens/physiology , Fertility/radiation effects , Light , Semen/metabolism , Animals , Body Weight , Chickens/growth & development , Male , Periodicity , Sexual Maturation , Testis/anatomy & histology , Testis/metabolism , Testosterone/blood
19.
Br J Hosp Med ; 44(5): 318, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2275992
20.
J Am Geriatr Soc ; 37(12): 1140-6, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2592721

ABSTRACT

The consequences of aging of the immune system include impaired T-lymphocyte responsiveness and aberrant immunoglobulin production. Although T cells from elderly individuals have a well-described defect in lymphoblastic transformation in response to some polyclonal mitogens, immunoglobulin abnormalities have lacked a clear in vitro model. Peripheral blood mononuclear cells from 13 young and 13 old healthy donors were cultured with phytohemagglutinin (PHA) or pokeweed mitogen (PWM). Old-donor-cell phytohemagglutinin (PHA), but not PWM, cultures had significantly lower lymphoblastic transformation compared with young donor cultures. IgG, IgA, and IgM production tended to be lower in old- versus young-donor PWM cell cultures. By contrast, despite lower lymphoblastic transformation in old-donor PHA cell cultures, immunoglobulin production was higher for old- versus young-donor cell cultures. No significant age differences were present in initial lymphocyte counts, percent B cells, T cells or monocytes, or helper/suppressor ratios to explain this enhancement in immunoglobulin production. PHA-stimulated mononuclear cell cultures in the aged demonstrate not only a defect in proliferation but also increased immunoglobulin production. This in vitro system may be useful to characterize further the pathogenesis of altered immunoglobulin production in the elderly.


Subject(s)
Aging/immunology , Immunoglobulins/biosynthesis , Leukocytes, Mononuclear/immunology , Adult , Aged , Aged, 80 and over , Cell Division/drug effects , Cells, Cultured , Humans , Immunoglobulin A/biosynthesis , Immunoglobulin G/biosynthesis , Immunoglobulin M/biosynthesis , Leukocytes, Mononuclear/cytology , Phytohemagglutinins/pharmacology , Pokeweed Mitogens/pharmacology
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