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1.
Phys Rev Lett ; 129(6): 061104, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36018635

RESUMO

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.
Ann Burns Fire Disasters ; 35(1): 46-54, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35582086

RESUMO

Optimal treatment of sepsis in burned patients depends on early diagnosis and includes prompt administration of antimicrobials as well as management of hemodynamic alterations and other organ dysfunctions. The role of red blood cell distribution width (RDW) and platelet indices in prognosticating and identifying sepsis in acute burn patients is studied. This study was done as a prospective study over 18 months, including patients in the age group >18 or <60 years, with burns >20% and <70% TBSA, burn time to resuscitation time 24 hours or less and with thermal and scald burns. Data of 157 patients were analyzed and the following observations were made. The mean age of the study population was 31.36 years (18-59 years). RDW values were higher in the non-survivor group. Platelet count and plateletcrit were higher in the survivor group and the no sepsis group. Positive rising trends of platelet count and plateletcrit were seen in the survivor group. Day 1, 3, 7 values of RDW, platelet count and plateletcrit were significant in determining the outcome of the patient on mortality and sepsis related morbidity of the patient. RDW, platelet count and plateletcrit in combination can predict mortality and sepsis as early as the third day, thus giving a clinical advantage of initiating targeted treatment to the at-risk burn population before sepsis is detected clinically. This could better the outcomes in treatment of burn patients.


Le traitement optimal du sepsis des brûlés dépend d'un diagnostic précoce et d'une antibiothérapie rapide ainsi que de la prise en charge du choc et des défaillances d'organe. Nous rapportons ici l'intérêt de l'index de distribution des globules rouges (IDGR) et d'indices plaquettaires dans le diagnostic et le pronostic du sepsis chez les brûlés. Nous présentons une étude prospective réalisée auprès de 157 patients de 18 à 60 ans (moyenne 31,36), brûlés sur 20 à 70% de SCT, pris en charge dans les 24 h après brûlure par flamme ou ébouillantement, recrutés pendant 18 mois. L'IDGR était plus élevés chez les patients décédés, quand la numération (NP) et le volume plaquettaire total (VPT) étaient plus élevés chez les survivants et les patients non infectés. La cinétique d'augmentation de NP et de VPT entre J1, J3 et J7 permettait de prédire sepsis et mortalité. Ainsi, IDGR, NP et VPT permettent de prédire la survenue de sepsis et un décès dès J3, permettant de débuter un traitement avant la survenue d'une infection, ce qui pourrait améliorer le devenir des brûlés.

3.
Phys Rev Lett ; 126(24): 241102, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213926

RESUMO

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.

5.
Br J Oral Maxillofac Surg ; 59(4): 407-412, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33771377

RESUMO

Pterygomaxillary (PTM) dysjunction is a technique-sensitive step in Le Fort I osteotomy. Various studies implicate improper osteotomy techniques and anatomical variations of the midface in ophthalmic/orbital complications. The aim of this study was to assess the stress distribution and its transmission to the orbit during PTM dysjunction while using different angulations of the osteotome. The study involved the generation of two virtual models from the computed tomographic images of a non-cleft and cleft patient. Nonlinear, three-dimensional finite element analysis (3D-FEA) of the models was performed for mapping the equivalent stress (in megapascals [MPa]) and maximum principal stress (in MPa) at the PTM junction, optic canal, and superior orbital fissures. The results of our study showed that there was no significant change in the transmission of stress to the bony orbit in a normal maxilla, with variations in the angulation of the osteotome. However, the equivalent stress generated for the cleft maxilla showed an increase that could potentiate indirect globe injury. The study shows that a judicious technique for PTM dysjunction and a cautious approach in cleft maxillae could reduce incidence of ophthalmic complications in clinical practice.


Assuntos
Maxila , Órbita , Análise de Elementos Finitos , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Órbita/diagnóstico por imagem , Órbita/cirurgia , Osteotomia de Le Fort , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/cirurgia
6.
Int J Oral Maxillofac Surg ; 50(4): 451-456, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32861556

RESUMO

The aim of this study was to evaluate changes in airflow characteristics before and after septoplasty in unilateral cleft lip and palate (UCLP) patients using computational fluid dynamics (CFD) models. The study was designed as a prospective cohort study involving pre- and postoperative computed tomography data from 12 UCLP patients with a deviated nasal septum who underwent septoplasty. CFD analysis of nasal airflow was conducted to study changes in velocity, pressure, volume, nasal resistance, and wall shear stress of the nasal domain before and after surgery. The study results demonstrated a statistically significant difference in pressure drop after septoplasty: median 116.10Pa (interquartile range (IQR) 749.02Pa) preoperative compared with 43.39Pa (IQR 349.01Pa) postoperative (P= 0.004). Maximum wall shear stress was found to be approximately three times lower after septoplasty: median 6.15 Pa (IQR 1908.62 Pa) preoperative versus median 2.51 Pa (IQR 540.06 Pa) postoperative (P=0.002). Changes in nasal resistance were also found to be statistically significant: median 460.59 Pa·s/l (IQR 1946.99 Pa·s/l) preoperative versus median 166.61 Pa·s/l (IQR 694.08 Pa·s/l) postoperative (P=0.04). These values demonstrate significant changes in flow dynamics after surgery indicative of a more uniform airflow pattern and stabilization of the nasal mucosa.


Assuntos
Fenda Labial , Obstrução Nasal , Rinoplastia , Fenda Labial/diagnóstico por imagem , Fenda Labial/cirurgia , Humanos , Hidrodinâmica , Obstrução Nasal/diagnóstico por imagem , Obstrução Nasal/cirurgia , Septo Nasal/diagnóstico por imagem , Septo Nasal/cirurgia , Estudos Prospectivos
7.
J Endocrinol Invest ; 44(7): 1425-1435, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33037580

RESUMO

PURPOSE: To present the data on primary hyperparathyroidism (PHPT) in pregnancy from India obtained from a large database maintained over 15 years. METHODS: We retrieved data of all women with gestational PHPT from the Indian PHPT registry between July 2005 and January 2020, and compared their clinical, biochemical, and other characteristics with age-matched non-pregnant women with PHPT. RESULTS: Out of 386 women, eight had gestational PHPT (2.1%). The common presenting manifestations were acute pancreatitis (50%) and renal stone disease (50%); two were asymptomatic. Five women (62.5%) had a history of prior miscarriages. Seven patients (88%) had preeclampsia during the present gestation. Serum calcium and intact parathyroid hormone (iPTH) were not statistically different from the age-matched non-pregnant PHPT group. Six patients with mild-to-moderate hypercalcemia were medically managed with hydration with/without cinacalcet while one patient underwent percutaneous ethanol ablation of the parathyroid adenoma; none underwent surgery during pregnancy. Mean serum calcium maintained from treatment initiation till delivery was 10.5 ± 0.4 mg/dl. One patient had spontaneous preterm delivery at 36 weeks; the remaining patients had normal vaginal delivery at term. None had severe preeclampsia/eclampsia. Fetal outcomes included low birth weight in three newborns (37.5%); two of them had hypocalcemic seizures. CONCLUSION: The prevalence of gestational PHPT was 2.1% in this largest Indian PHPT cohort, which is higher than that reported from the West (< 1%). Gestational PHPT can lead to preeclampsia and miscarriage. Pregnant PHPT patients with mild-to-moderate hypercalcemia can be managed with hydration/cinacalcet; however, long-term safety data and large-scale randomized controlled trials are required.


Assuntos
Hiperparatireoidismo Primário/epidemiologia , Pré-Eclâmpsia/patologia , Complicações na Gravidez/patologia , Nascimento Prematuro/patologia , Sistema de Registros/estatística & dados numéricos , Adulto , Feminino , Seguimentos , Humanos , Hiperparatireoidismo Primário/complicações , Índia/epidemiologia , Recém-Nascido , Pré-Eclâmpsia/etiologia , Gravidez , Complicações na Gravidez/etiologia , Nascimento Prematuro/etiologia , Prognóstico
8.
Living Rev Relativ ; 23(1): 3, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33015351

RESUMO

We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of 10 5 , 10 6 , 10 7 Mpc 3 for binary neutron star, neutron star-black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of 1 - 1 + 12 ( 10 - 10 + 52 ) for binary neutron star mergers, of 0 - 0 + 19 ( 1 - 1 + 91 ) for neutron star-black hole mergers, and 17 - 11 + 22 ( 79 - 44 + 89 ) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.

9.
Phys Rev Lett ; 125(10): 101102, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32955328

RESUMO

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}.

10.
Br J Oral Maxillofac Surg ; 58(8): 970-974, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32456996

RESUMO

The aim of the study was to compare interpositional arthroplasty using a dermis fat graft with gap arthroplasty in the management of ankylosis of the temporomandibular joint (TMJ). We organised a prospective randomised study of 22 patients who presented with ankylosis of the TMJ. They were randomised to be treated with either plain gap arthroplasty or dermis fat arthroplasty, and the predictor variable was the method of treatment. The primary outcome variables were mouth opening and pain on jaw exercises. Pain and interincisal opening were measured on day 5, day 14, at the end of one month, and at six months, one year, two years, and three years. There was a significant difference between the two groups on two occasions: postoperative day 5 (p=0.013) and at one year (p=0.018). The mean (SD) scores for mouth-opening were higher in the dermis fat group at all times (41.20 (4.69) mm compared with 39.50 (2.46) mm in gap arthroplasty at two years, and 41.40 (3.60) mm compared with 38.9 (2.02) mm at three years). The visual analogue pain scores were also lower in the dermis fat graft group. The groups showed similar results at the end of three years follow up, with no significant difference in mouth opening. We conclude therefore that the two techniques have similar outcomes in the management of ankylosis of the TMJ.


Assuntos
Anquilose , Transtornos da Articulação Temporomandibular , Anquilose Dental , Anquilose/cirurgia , Artroplastia , Derme , Humanos , Estudos Prospectivos , Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/cirurgia
12.
Phys Rev Lett ; 123(16): 161102, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31702344

RESUMO

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.

13.
J Prev Alzheimers Dis ; 6(4): 267-273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686099

RESUMO

OBJECTIVE: This study sought to determine if the MIND diet (a hybrid of the Mediterranean and Dash diets, with modifications based on the science of nutrition and the brain), is effective in preventing cognitive decline after stroke. DESIGN: We analyzed 106 participants of a community cohort study who had completed a diet assessment and two or more annual cognitive assessments and who also had a clinical history of stroke. Cognition in five cognitive domains was assessed using structured clinical evaluations that included a battery of 19 cognitive tests. MIND diet scores were computed using a valid food frequency questionnaire (FFQ). Dietary components of the MIND diet included whole grains, leafy greens and other vegetables, berries, beans, nuts, lean meats, fish, poultry, and olive oil and reduced consumption of cheese, butter, fried foods, and sweets. MIND diet scores were modeled in tertiles. The influence of baseline MIND score on change in a global cognitive function measure and in the five cognitive domains was assessed using linear mixed models adjusted for age and other potential confounders. RESULTS: With adjustment for age, sex, education, APOE-ε4, caloric intake, smoking, and participation in cognitive and physical activities, the top vs lowest tertiles of MIND diet scores had a slower rate of global cognitive decline (ß = .08; CI = 0.0074, 0.156) over an average of 5.9 years of follow-up. CONCLUSIONS: High adherence to the MIND diet was associated with a slower rate of cognitive decline after stroke.


Assuntos
Disfunção Cognitiva/fisiopatologia , Dieta Mediterrânea , Abordagens Dietéticas para Conter a Hipertensão , Acidente Vascular Cerebral/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Progressão da Doença , Feminino , Humanos , Masculino , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia
14.
Phys Rev Lett ; 123(1): 011102, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31386391

RESUMO

The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR.

15.
BJOG ; 126 Suppl 4: 14-20, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257693

RESUMO

OBJECTIVE: To analyse the aetiology of stillbirth and its changing trends in a single tertiary care referral institute of northern India over a 10-year period (2007-2016). DESIGN: Retrospective study. SETTING: Tertiary care hospital in the north of India. SAMPLE: Medical records of all mothers who delivered a stillborn at the institute. METHODS: Data was collected from monthly and annual perinatal audits and causes of stillbirths were classified using Simplified CODAC classification. Annual reduction rate was calculated by linear regression analysis and Cusick test for the changing trends over 9 years. MAIN OUTCOME MEASURES: Of 54 160 births, 3678 babies were stillborn. Over 9 years, the annual stillbirth rate has reduced significantly from 73.6 to 62.0 per 1000 total births with an average annual reduction rate of 1%. The most common causes of stillbirths were hypertensive disorders of pregnancy (27.6%), antepartum haemorrhage (19.5%), and congenital anomalies (9.3%). CONCLUSION: The annual reduction rate (1%) of stillbirth remains low. The aetiology of stillbirths remains unchanged over a 10-year period and hypertensive disorder of pregnancy remains the single most preventable cause of stillbirth. TWEETABLE ABSTRACT: Analysis of stillbirths over a 10-year period in an Indian institute showed a high but declining trend with annual reduction rate of 1%.


Assuntos
Causas de Morte , Natimorto/epidemiologia , Adulto , Feminino , Doenças Fetais/epidemiologia , Idade Gestacional , Humanos , Índia/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Cuidado Pré-Natal/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária/estatística & dados numéricos , Adulto Jovem
16.
Respir Med ; 148: 60-62, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30827477

RESUMO

Human blood monocytes are divided into populations based on the differential expression of CD14 and CD16 receptors: CD14 + CD16(classical), CD14 + CD16 + (intermediate), and CD14-CD16+ (non-classical). Given their functional differences and their role in pathogenesis of chronic obstructive pulmonary disease (COPD), monocyte profiling is of clinical interest. Here we investigated blood monocyte subsets in clinically stable COPD patients with alpha1-antitrypsin (AAT) deficiency (PiZZ, n = 7) and with normal AAT variant (PiMM, n = 7). Peripheral whole blood was collected in sodium heparin tubes and incubated with LPS (from E. coli; 1 µg/ml) or placebo for 6 h at 37 °C, 5% CO2. To profile monocyte subsets we performed flow cytometry analysis based on HLA-DR and CD14/CD16 staining. HLA-DR + subsets of cells did not differ between PiZZ and PiMM COPD, and healthy controls (n = 7), used as a reference. Monocyte profiling, which express the CD14 and CD16, but not the HLA-DR (HLA-DR-) showed that intermediate monocytes subset was lowest in PiZZ group, and almost totally disappeared from blood treated with LPS. The non-classical subset was almost absent in PiZZ patients independently of LPS treatment. Recent studies demonstrate that non-classical monocytes exhibit a unique ability to protect the vascular endothelium under both homeostatic and inflammatory conditions whereas intermediate monocytes are recruited at a later stage of inflammation, and are associated with secretion of cytokines/chemokines and wound healing. Evident alterations in blood monocyte subsets together with a partial reduction of AAT levels, an important anti-inflammatory protein, can be key factors for the early manifestation of emphysema in some PiZZ AATD carriers.


Assuntos
Monócitos/metabolismo , Doença Pulmonar Obstrutiva Crônica/sangue , Deficiência de alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismo , Idoso , Feminino , Citometria de Fluxo/métodos , Antígenos HLA-DR/metabolismo , Humanos , Inflamação/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Fenótipo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Receptores de IgG/metabolismo , alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/complicações
17.
Phys Rev Lett ; 122(6): 061104, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822067

RESUMO

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnB_{!pg}^{pg}) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models that neglect p-g effects, with lnB_{!pg}^{pg}=0.03_{-0.58}^{+0.70} (maximum a posteriori and 90% credible region). By injecting simulated signals that do not include p-g effects and recovering them with the p-g model, we show that there is a ≃50% probability of obtaining similar lnB_{!pg}^{pg} even when p-g effects are absent. We find that the p-g amplitude for 1.4 M_{⊙} neutron stars is constrained to less than a few tenths of the theoretical maximum, with maxima a posteriori near one-tenth this maximum and p-g saturation frequency ∼70 Hz. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest ≲10^{3} modes saturate by wave breaking. Thus, the measured constraints only rule out extreme values of the p-g parameters. They also imply that the instability dissipates ≲10^{51} erg over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.

18.
Phys Rev Lett ; 121(23): 231103, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30576173

RESUMO

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2 M_{⊙}-1.0 M_{⊙} using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2 M_{⊙}, 0.2 M_{⊙}) ultracompact binaries to be less than 1.0×10^{6} Gpc^{-3} yr^{-1} and the coalescence rate of a similar distribution of (1.0 M_{⊙}, 1.0 M_{⊙}) ultracompact binaries to be less than 1.9×10^{4} Gpc^{-3} yr^{-1} (at 90% confidence). Neither black holes nor neutron stars are expected to form below ∼1 M_{⊙} through conventional stellar evolution, though it has been proposed that similarly low mass black holes could be formed primordially through density fluctuations in the early Universe and contribute to the dark matter density. The interpretation of our constraints in the primordial black hole dark matter paradigm is highly model dependent; however, under a particular primordial black hole binary formation scenario we constrain monochromatic primordial black hole populations of 0.2 M_{⊙} to be less than 33% of the total dark matter density and monochromatic populations of 1.0 M_{⊙} to be less than 5% of the dark matter density. The latter strengthens the presently placed bounds from microlensing surveys of massive compact halo objects (MACHOs) provided by the MACHO and EROS Collaborations.

19.
Phys Rev Lett ; 121(16): 161101, 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30387654

RESUMO

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function p(ρ) of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as R_{1}=10.8_{-1.7}^{+2.0} km for the heavier star and R_{2}=10.7_{-1.5}^{+2.1} km for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than 1.97 M_{⊙} as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain R_{1}=11.9_{-1.4}^{+1.4} km and R_{2}=11.9_{-1.4}^{+1.4} km at the 90% credible level. Finally, we obtain constraints on p(ρ) at supranuclear densities, with pressure at twice nuclear saturation density measured at 3.5_{-1.7}^{+2.7}×10^{34} dyn cm^{-2} at the 90% level.

20.
Oral Maxillofac Surg ; 22(4): 463-474, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30203137

RESUMO

PURPOSE: Unilateral or bilateral ankylosis can lead to severe micrognathia and facial deformity that requires multiple, often, staged surgical corrections. To date, there is no ideal treatment modality that satisfactorily corrects the complex anatomy, restores the ramal height, and corrects the micrognathia and microgenia. Distraction osteogenesis has been acclaimed as a successful modality for the treatment of such deformities. It is a cost-effective approach with low morbidity and less relapse thus providing better functional and esthetic outcomes. It allows the surgeon to correct the deformity in various planes by using various devices by changing osteotomy designs and vectors, with simultaneous hard tissue and soft tissue reconstruction. PATIENTS AND METHODS: Here, we present a series of five cases where different types of distraction osteogenesis were combined with various other procedures to correct post-ankylotic facial asymmetry. In one case, simultaneous maxillo-mandibular distraction [Molina's technique] was used. RESULTS: All patients showed significant improvement in function and esthetics. Outcome assessment was made using clinical photographs and radiographs. CONCLUSION: Pre-arthroplastic distraction osteogenesis is a versatile cost effective approach that can be customized for every patient based on their needs.


Assuntos
Anquilose/complicações , Assimetria Facial/etiologia , Mandíbula/anormalidades , Micrognatismo/etiologia , Osteogênese por Distração/métodos , Transtornos da Articulação Temporomandibular/complicações , Adolescente , Assimetria Facial/diagnóstico por imagem , Assimetria Facial/cirurgia , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Micrognatismo/diagnóstico por imagem , Micrognatismo/cirurgia , Radiografia , Resultado do Tratamento , Adulto Jovem
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