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The ability to efficiently control charge and spin in the cuprate high-temperature superconductors is crucial for fundamental research and underpins technological development. Here, we explore the tunability of magnetism, superconductivity, and crystal structure in the stripe phase of the cuprate La[Formula: see text]Ba[Formula: see text]CuO[Formula: see text], with [Formula: see text] = 0.115 and 0.135, by employing temperature-dependent (down to 400 mK) muon-spin rotation and AC susceptibility, as well as X-ray scattering experiments under compressive uniaxial stress in the CuO[Formula: see text] plane. A sixfold increase of the three-dimensional (3D) superconducting critical temperature [Formula: see text] and a full recovery of the 3D phase coherence is observed in both samples with the application of extremely low uniaxial stress of [Formula: see text]0.1 GPa. This finding demonstrates the removal of the well-known 1/8-anomaly of cuprates by uniaxial stress. On the other hand, the spin-stripe order temperature as well as the magnetic fraction at 400 mK show only a modest decrease under stress. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. However, strain produces an inhomogeneous suppression of the spin-stripe order at elevated temperatures. Namely, a substantial decrease of the magnetic volume fraction and a full suppression of the low-temperature tetragonal structure is found under stress, which is a necessary condition for the development of the 3D superconducting phase with optimal [Formula: see text]. Our results evidence a remarkable cooperation between the long-range static spin-stripe order and the underlying crystalline order with the three-dimensional fully coherent superconductivity. Overall, these results suggest that the stripe- and the SC order may have a common physical mechanism.
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PURPOSE: To present a series of patients with RPE65-related retinal dystrophy showing a partial rescue of the full-field electroretinogram (ERG) following gene replacement therapy with voretigene neparovec-rzyl (Luxturna®). METHODS: This retrospective chart review examined 17 patients treated with voretigene neparovec-rzyl (VN) at the Casey Eye Institute (2018-2022). The last pre-operative ERG and all available post-operative ERGs were analyzed to identify subjects with functional rescue. Measurements of amplitudes and implicit times were compared to data from age-matched controls and the attenuation relative to the lower limit of normal (LLN) was calculated. For comparison with other functional exams, the last pre-operative and all post-treatment best-corrected visual acuity (BCVA) data, visual field (VF) tests and full-field threshold stimulus tests (FST) were also described. RESULTS: Of patients who underwent ERGs, most had unrecordable ERGs that did not change after treatment. However, we identified three patients, treated bilaterally, who demonstrated partial rescue of the full-field ERG in both eyes which was sustained during the course of the study. CONCLUSIONS: This is the largest series of patients treated with VN showing a partial rescue of the ERG. This is also the first report of bilateral ERG rescue, as well as the first description of ERG recovery occurring in non-pediatric subjects. Full-field ERG could be used in combination with other psychophysical tests and imaging modalities to detect and deepen our understanding of the response to this gene therapy approach.
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In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced Virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced Virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.
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We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2 M_{â} and 1.0 M_{â} 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_{â}
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AIM: To compare accuracy, efficacy and acceptance of implantable and transcutaneous continuous glucose monitoring (CGM) systems. METHODS: In a randomized crossover trial we compared 12 weeks with Eversense implantable sensor (EVS) and 12 weeks with Dexcom G5 transcutaneous sensor (DG5) in terms of accuracy, evaluated as Mean Absolute Relative Difference (MARD) vs capillary glucose (SMBG), time of CGM use, adverse events, efficacy (as HbA1c, time in range, time above and below range) and psychological outcomes evaluated with Diabetes Treatment Satisfaction Questionnaire (DTSQ), Glucose Monitoring Satisfaction Survey (GMSS), Hypoglycemia Fear Survey (HFS2), Diabetes Distress Scale (DDS). RESULTS: 16 subjects (13 males, 48.8 ± 10.1 years, HbA1c 55.8 ± 7.9 mmol/mol, mean ± SD) completed the study. DG5 was used more than EVS [percentage of use 95.7 ± 3.6% vs 93.5 ± 4.3% (p = 0.02)]. MARD was better with EVS (12.2 ± 11.5% vs. 13.1 ± 14.7%, p< 0.001). No differences were found in HbA1c. While using EVS time spent in range increased and time spent in hyperglycemia decreased, but these data were not confirmed by analysis of retrofitted data based on SMBG values. EVS reduced perceived distress, without significant changes in other psychological outcomes. CONCLUSIONS: CGM features may affect glycemic control and device acceptance.
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Diabetes Mellitus Tipo 1/sangue , Controle Glicêmico/instrumentação , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Automonitorização da Glicemia/efeitos adversos , Automonitorização da Glicemia/instrumentação , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/psicologia , Feminino , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Controle Glicêmico/efeitos adversos , Humanos , Implantes Experimentais/efeitos adversos , Insulina/administração & dosagem , Sistemas de Infusão de Insulina/efeitos adversos , Itália , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
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: Gµâ²4×10^{-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.
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Perforated diverticulitis is an emergent clinical condition and its management is challenging and still debated. The aim of this position paper was to critically review the available evidence on the management of perforated diverticulitis and generalized peritonitis in order to provide evidence-based suggestions for a management strategy. Four Italian scientific societies (SICCR, SICUT, SIRM, AIGO), selected experts who identified 5 clinically relevant topics in the management of perforated diverticulitis with generalized peritonitis that would benefit from a multidisciplinary review. The following 5 issues were tackled: 1) Criteria to decide between conservative and surgical treatment in case of perforated diverticulitis with peritonitis; 2) Criteria or scoring system to choose the most appropriate surgical option when diffuse peritonitis is confirmed 3); The appropriate surgical procedure in hemodynamically stable or stabilized patients with diffuse peritonitis; 4) The appropriate surgical procedure for patients with generalized peritonitis and septic shock and 5) Optimal medical therapy in patients with generalized peritonitis from diverticular perforation before and after surgery. In perforated diverticulitis surgery is indicated in case of diffuse peritonitis or failure of conservative management and the decision to operate is not based on the presence of extraluminal air. If diffuse peritonitis is confirmed the choice of surgical technique is based on intraoperative findings and the presence or risk of severe septic shock. Further prognostic factors to consider are physiological derangement, age, comorbidities, and immune status. In hemodynamically stable patients, emergency laparoscopy has benefits over open surgery. Options include resection and anastomosis, Hartmann's procedure or laparoscopic lavage. In generalized peritonitis with septic shock, an open surgical approach is preferred. Non-restorative resection and/or damage control surgery appear to be the only viable options, depending on the severity of hemodynamic instability. Multidisciplinary medical management should be applied with the main aims of controlling infection, relieving postoperative pain and preventing and/or treating postoperative ileus. In conclusion, the complexity and diversity of patients with diverticular perforation and diffuse peritonitis requires a personalized strategy, involving a thorough classification of physiological derangement, staging of intra-abdominal infection and choice of the most appropriate surgical procedure.
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Doença Diverticular do Colo , Diverticulite , Perfuração Intestinal , Laparoscopia , Peritonite , Anastomose Cirúrgica , Colostomia , Diverticulite/cirurgia , Doença Diverticular do Colo/cirurgia , Humanos , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Itália , Peritonite/complicações , Peritonite/cirurgiaRESUMO
We report muon spin rotation and magnetic susceptibility experiments on in-plane stress effects on the static spin-stripe order and superconductivity in the cuprate system La_{2-x}Ba_{x}CuO_{4} with x=0.115. An extremely low uniaxial stress of â¼0.1 GPa induces a substantial decrease in the magnetic volume fraction and a dramatic rise in the onset of 3D superconductivity, from â¼10 to 32 K; however, the onset of at-least-2D superconductivity is much less sensitive to stress. These results show not only that large-volume-fraction spin-stripe order is anticorrelated with 3D superconducting coherence but also that these states are energetically very finely balanced. Moreover, the onset temperatures of 3D superconductivity and spin-stripe order are very similar in the large stress regime. These results strongly suggest a similar pairing mechanism for spin-stripe order and the spatially modulated 2D and uniform 3D superconducting orders, imposing an important constraint on theoretical models.
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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_{â} and 66_{-18}^{+17} M_{â} (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_{â}. We calculate the mass of the remnant to be 142_{-16}^{+28} M_{â}, 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}.
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The quantum radiation pressure and the quantum shot noise in laser-interferometric gravitational wave detectors constitute a macroscopic manifestation of the Heisenberg inequality. If quantum shot noise can be easily observed, the observation of quantum radiation pressure noise has been elusive, so far, due to the technical noise competing with quantum effects. Here, we discuss the evidence of quantum radiation pressure noise in the Advanced Virgo gravitational wave detector. In our experiment, we inject squeezed vacuum states of light into the interferometer in order to manipulate the quantum backaction on the 42 kg mirrors and observe the corresponding quantum noise driven displacement at frequencies between 30 and 70 Hz. The experimental data, obtained in various interferometer configurations, is tested against the Advanced Virgo detector quantum noise model which confirmed the measured magnitude of quantum radiation pressure noise.
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AIM: The optimal surgical treatment of splenic flexure neoplasm is still not well defined. Extended right hemicolectomy (ERH) and left colic resection (LCR) have been proposed but conclusive evidence concerning postoperative morbidity and oncological results is lacking. The aim of this study was to analyse the short-term outcomes after surgery for splenic flexure cancer with regard to surgical procedure and surgeon's specialty. METHODS: This was a multicentre study on patients who underwent surgery for primary colon cancer of the splenic flexure. RESULTS: From 2004 to 2015, 324 patients fulfilled the criteria for inclusion into the study; 270 (83.4%) had elective surgery while 54 (16.6%) had emergency resection: 158 (48.8%) underwent ERH and 166 (51.2%) LCR; 176 (54.3%) procedures were performed by colorectal surgeons, 148 (46.7%) by general surgeons. In the ERH group a significantly higher rate of emergency operations was carried out (P = 0.005). After elective surgery, no significant differences between ERH and LCR concerning 30-day mortality (3.3% vs 2.0%) and the need for reoperation (10.6% vs 7.4%) were found. Nodal harvesting was significantly higher in the ERH and colorectal surgeon groups in any clinical scenario. At multivariate analysis, age and smoking habit were predictive of the need for reoperation and major morbidity while the general surgeon group showed a higher risk of anastomotic failure (OR = 1.92; P = 0.168). CONCLUSION: We analysed the largest series in literature of curative resections for splenic flexure tumours. The optimal procedure still remains debatable as ERH and LCR appear to achieve comparable short-term outcomes. Surgeon's specialty seems to positively affect patient's outcomes.
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Colectomia/estatística & dados numéricos , Colo Transverso/cirurgia , Neoplasias do Colo/cirurgia , Reoperação/estatística & dados numéricos , Cirurgiões/estatística & dados numéricos , Idoso , Colectomia/métodos , Colo Transverso/patologia , Neoplasias do Colo/patologia , Cirurgia Colorretal/estatística & dados numéricos , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Tratamento de Emergência/métodos , Tratamento de Emergência/estatística & dados numéricos , Feminino , Cirurgia Geral/estatística & dados numéricos , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
Coating thermal noise is a fundamental limit for precision experiments based on optical and quantum transducers. In this review, after a brief overview of the techniques for coating thermal noise measurements, we present the latest worldwide research activity on low-noise coatings, with a focus on the results obtained at the Laboratoire des Matériaux Avancés. We report new updated values for the Ta2O5, Ta2O5-TiO2, and SiO2 coatings of the Advanced LIGO, Advanced Virgo, and KAGRA detectors, and new results from sputtered Nb2O5, TiO2-Nb2O5, Ta2O5-ZrO2, MgF2, AlF3, and silicon nitride coatings. Amorphous silicon, crystalline coatings, high-temperature deposition, multi-material coatings, and composite layers are also briefly discussed, together with the latest developments in structural analyses and models.
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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.
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Perianal sepsis is a common condition ranging from acute abscess to chronic anal fistula. In most cases, the source is considered to be a non-specific cryptoglandular infection starting from the intersphincteric space. Surgery is the main treatment and several procedures have been developed, but the risks of recurrence and of impairment of continence still seem to be an unresolved issue. This statement reviews the pertinent literature and provides evidence-based recommendations to improve individualized management of patients.
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Doenças do Ânus , Fístula Retal , Sepse , Dermatopatias , Abscesso/etiologia , Abscesso/cirurgia , Doenças do Ânus/etiologia , Doenças do Ânus/cirurgia , Humanos , Fístula Retal/etiologia , Fístula Retal/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Epidemiological studies show an increasing trend of hospitalization for acute diverticulitis (AD), but data regarding the trend in hospitalization for complicated AD in Italy are scarce. The aim of this study was to analyze the Italian trend in hospitalization for complicated AD, from 2008 to 2015. METHODS: Using the Italian Hospital Information System, we identified all patients with complicated colonic AD as a discharge diagnosis. Age- and sex-specific rates for AD as well as type of hospital admission (emergency/elective), type of complication (peritonitis, obstruction, bleeding, abscess, fistula, perforation, sepsis) and type of treatment (medical/surgical), were analyzed. RESULTS: A total of 41,622 patients with a discharge diagnosis of complicated AD were identified. Over the study period the admission rate grew from 8.8 to 11.8 per 100,000 inhabitants. The hospitalization rate was highest for patients ≥ 70 years, but the increase in the admission rate was higher among patients aged ≤ 60 years. There were more males in the group < 60 years and more females in the group ≥ 60 years old. The rate of emergency admissions associated with surgery showed a significant mean annual increase (+ 3.9% per year) in the rate of emergency admissions associated with surgery, whereas elective admissions for surgery remained stable. Peritonitis was the most frequent complication (35.5%). The rate of surgery increased in AD complicated by peritonitis (+ 5.1% per year), abscess (+ 5.8% per year) and decreased for obstruction (- 1.8% per year). CONCLUSIONS: From 2008 to 2015, we documented an increasing rate of hospitalization for complicated AD, especially for younger patients, with an increase in surgery for peritonitis and abscess. Further studies are needed to clearly assess the risk factors for complications and risk of surgery.
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Doença Diverticular do Colo , Diverticulite , Doença Aguda , Idoso , Diverticulite/complicações , Diverticulite/epidemiologia , Diverticulite/cirurgia , Doença Diverticular do Colo/complicações , Doença Diverticular do Colo/epidemiologia , Doença Diverticular do Colo/cirurgia , Feminino , Hospitalização , Hospitais , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Colonic J pouch reconstruction has been found to be associated with a lower incidence of anastomotic leakage than straight anastomosis. However, studies on this topic are underpowered and retrospective. This randomized trial evaluated whether the incidence of anastomotic leakage was reduced after colonic J pouch reconstruction compared with straight colorectal anastomosis following anterior resection for rectal cancer. METHODS: This multicentre RCT included patients with rectal carcinoma who underwent low anterior resection followed by colorectal anastomosis. Patients were assigned randomly to receive a colonic J pouch or straight colorectal anastomosis. The main outcome measure was the occurrence of major anastomotic leakage. The incidence of global (major plus minor) anastomotic leakage and general complications were secondary outcomes. Risk factors for anastomotic leakage were identified by regression analysis. RESULTS: Of 457 patients enrolled, 379 were evaluable (colonic J pouch arm 190, straight colorectal arm 189). The incidence of major and global anastomotic leakage, and general complications was 14·2, 19·5 and 34·2 per cent respectively in the colonic J pouch group, and 12·2, 19·0 and 27·0 per cent in the straight colorectal anastomosis group. No statistically significant differences were observed between the two arms. In multivariable logistic regression analysis, male sex (odds ratio 1·79, 95 per cent c.i. 1·02 to 3·15; P = 0·042) and high ASA fitness grade (odds ratio 2·06, 1·15 to 3·71; P = 0·015) were independently associated with the occurrence of anastomotic leakage. CONCLUSION: Colonic J pouch reconstruction does not reduce the incidence of anastomotic leakage and postoperative complications compared with conventional straight colorectal anastomosis. Registration number NCT01110798 (http://www.clinicaltrials.gov).
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Colo/cirurgia , Bolsas Cólicas , Procedimentos de Cirurgia Plástica , Neoplasias Retais/cirurgia , Reto/cirurgia , Grampeamento Cirúrgico , Idoso , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Fístula Anastomótica/epidemiologia , Fístula Anastomótica/etiologia , Bolsas Cólicas/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos , Grampeamento Cirúrgico/métodosRESUMO
We report muon spin rotation and magnetization measurements under pressure on Fe_{1+δ}Se_{1-x}S_{x} with x≈0.11. Above p≈0.6 GPa we find a microscopic coexistence of superconductivity with an extended dome of long range magnetic order that spans a pressure range between previously reported separated magnetic phases. The magnetism initially competes on an atomic scale with the coexisting superconductivity leading to a local maximum and minimum of the superconducting T_{c}(p). The maximum of T_{c} corresponds to the onset of magnetism while the minimum coincides with the pressure of strongest competition. A shift of the maximum of T_{c}(p) for a series of single crystals with x up to 0.14 roughly extrapolates to a putative magnetic and superconducting state at ambient pressure for x≥0.2.
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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_{â} 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 â¼70 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 â²10^{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 â²10^{51} erg over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.
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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.
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Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometer's dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1 dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%-8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded.