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1.
Phys Rev Lett ; 129(6): 061104, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-36018635

RESUMEN

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2 M_{⊙} and 1.0 M_{⊙} in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14 yr^{-1}. This implies an upper limit on the merger rate of subsolar binaries in the range [220-24200] Gpc^{-3} yr^{-1}, depending on the chirp mass of the binary. We use this upper limit to derive astrophysical constraints on two phenomenological models that could produce subsolar-mass compact objects. One is an isotropic distribution of equal-mass primordial black holes. Using this model, we find that the fraction of dark matter in primordial black holes in the mass range 0.2 M_{⊙}

2.
Phys Rev Lett ; 126(24): 241102, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34213926

RESUMEN

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gµ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gµ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gµâ‰²4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

3.
Phys Rev Lett ; 125(10): 101102, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32955328

RESUMEN

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21} M_{⊙} and 66_{-18}^{+17} M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65 M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28} M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4} Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30} Gpc^{-3} yr^{-1}.

4.
Phys Rev Lett ; 123(16): 161102, 2019 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-31702344

RESUMEN

We present a search for subsolar mass ultracompact objects in data obtained during Advanced LIGO's second observing run. In contrast to a previous search of Advanced LIGO data from the first observing run, this search includes the effects of component spin on the gravitational waveform. We identify no viable gravitational-wave candidates consistent with subsolar mass ultracompact binaries with at least one component between 0.2 M_{⊙}-1.0 M_{⊙}. We use the null result to constrain the binary merger rate of (0.2 M_{⊙}, 0.2 M_{⊙}) binaries to be less than 3.7×10^{5} Gpc^{-3} yr^{-1} and the binary merger rate of (1.0 M_{⊙}, 1.0 M_{⊙}) binaries to be less than 5.2×10^{3} Gpc^{-3} yr^{-1}. Subsolar mass ultracompact objects are not expected to form via known stellar evolution channels, though it has been suggested that primordial density fluctuations or particle dark matter with cooling mechanisms and/or nuclear interactions could form black holes with subsolar masses. Assuming a particular primordial black hole (PBH) formation model, we constrain a population of merging 0.2 M_{⊙} black holes to account for less than 16% of the dark matter density and a population of merging 1.0 M_{⊙} black holes to account for less than 2% of the dark matter density. We discuss how constraints on the merger rate and dark matter fraction may be extended to arbitrary black hole population models that predict subsolar mass binaries.

5.
Clin Ther ; 19(1): 139-47; discussion 126-7, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9083716

RESUMEN

Schizophrenia is arguably the worst disease affecting humankind, costly in both social and financial terms. In the current cost-cutting climate, the focus is on economizing the delivery of health care, including reducing access to prescription drugs. Yet decreasing expenditures on drugs for severe illnesses, such as schizophrenia, is a false economy. Drugs account for only a small proportion of the total costs of treating schizophrenia, with inpatient hospital care comprising the greatest portion of total treatment costs. Thus the use of risperidone, a more effective but more expensive antipsychotic medication, can decrease the total cost of care for patients with chronic schizophrenia by decreasing the need for hospitalization. Fewer days spent in the hospital also often means a better quality of life for patients. This finding is illustrated by case histories of 3 patients, 2 with schizophrenia and 1 elderly patient with behavioral disturbances of dementia.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/economía , Antipsicóticos/economía , Antipsicóticos/uso terapéutico , Risperidona/economía , Risperidona/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/economía , Adulto , Anciano , Antipsicóticos/efectos adversos , Análisis Costo-Beneficio , Costos de los Medicamentos , Femenino , Haloperidol/uso terapéutico , Hospitalización/economía , Humanos , Masculino , Calidad de Vida , Risperidona/efectos adversos
6.
J Am Podiatr Med Assoc ; 85(4): 226-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7738822

RESUMEN

A case of osteochondrosis of the tarsal navicular in an adult is presented. The patient was not fully compliant with the recommendations of the physicians involved and, as a result, full recovery has not been accomplished. Left untreated or undertreated, Mueller-Weiss syndrome can result in severe permanent osteoarthritis of the midtarsal joint (talonavicular joint). This may result in permanent deformity and disability. Properly treated with rest and supportive therapy, the condition is self-limiting and should heal without any sequela.


Asunto(s)
Osteocondritis/diagnóstico , Carrera , Huesos Tarsianos , Adolescente , Diagnóstico Diferencial , Femenino , Humanos , Osteocondritis/terapia
7.
Med Health R I ; 79(2): 60-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8907154

RESUMEN

A brief demographic profile of the 466 physicians applying for licensure in Rhode Island in the year 1895, is presented here. The typical Rhode Island physician of a century ago was a New England-born 39-year-old white male general practitioner who had little undergraduate education, received his medical diploma from an allopathic medical school within 180 miles of his place of birth, typically a small town, had little or no supervised hospital training, professed to no specialty and established his office, often sharing space with his practitioner-father, within the same community in which he was born.


Asunto(s)
Licencia Médica/historia , Médicos/historia , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Licencia Médica/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Médicos/estadística & datos numéricos , Rhode Island , Facultades de Medicina/historia , Facultades de Medicina/estadística & datos numéricos , Estados Unidos
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