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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 present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over Ë]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over Ë]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.
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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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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.
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Pathogenic bacteria are responsible for a significant number of food poisonings in humans through infected poultries. The main objective of this study was to assess the effect of transportation of chicken carcasses at 18-24, 4-5, and 10-14 oC on the bacterial loads of Staphylococcus aureus, Salmonella species, and Escherichia coli. This study was conducted on 180 fresh chicken carcasses (1197.0±19.88 g) randomly collected from a commercial poultry processing plant in southern Tehran, Iran, in a hot season in 2015. The sampling was performed at two stages, namely post-chilled washing and after 4 h of transportation. In the latter stage, the samples were selected from three vehicles with three types of temperatures. These vehicles included a pickup (18-24 oC), a refrigerated car (4-5 oC), and a refrigerated vehicle with switched off refrigerator (10-14 oC). According to the results, the whole body carcass samples transported at the pickup temperature had the highest mean total count (18.63×106±2.82×106 cfu.ml-1) and was greater (P<0.05) than the standard limit (5×106). On the other hand, the samples carried by the vehicle with switched off refrigerator had the lowest total count (0.65±0.04×106 cfu.ml-1). Similar results were obtained for S. aureus; accordingly, it reached the maximum (333.0±30.73 cfu.ml-1) at 18-24 oC, which was lower than the national standard limit even after 4 h of transportation. In addition, the cfu values for the total count and S. aureus sampled from the chicken carcasses were lower than the national standard level even after 4 h of carcass transportation, with the exception of Salmonella spp. at the three vehicle temperatures and E. coli at the pickup temperature. It was suggested that the transportation temperature of less than 10-14 oC could not affect the fresh chicken carcass to be contaminated with S. aureus and E. coli.
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Carga Bacteriana , Escherichia coli/fisiologia , Manipulação de Alimentos/métodos , Carne/microbiologia , Salmonella/fisiologia , Staphylococcus aureus/fisiologia , Meios de Transporte/métodos , Animais , Galinhas , Microbiologia de Alimentos , Irã (Geográfico) , TemperaturaRESUMO
AIMS: Enterohaemorrhagic Escherichia coli serotype O157:H7 as a major human pathogen is responsible for food borne outbreaks, bloody diarrhoea, haemorrhagic colitis and haemolytic uraemic syndrome and even death. In this study, the antibacterial activity of the Zataria multiflora essential oil (ZMEO) and nanoliposome-encapsulated ZMEO was evaluated on the pathogenicity of E. coli O157:H7. METHODS AND RESULTS: The minimum inhibitory concentrations (MIC) of essential oil (EO) were determined against the bacterium before and after encapsulation into nanoliposome. Then, the effect of subinhibitory concentrations was evaluated on Shiga toxin 2 (Stx2) production. The effect of free and nanoliposomal EO was also studied on the gene expression of Stx2 by real-time PCR. It was found that inhibitory activity of EO was improved after incorporation into nanoliposomes (P < 0·05). The MIC of free EO against E. coli O157:H7 was 0·03% (v/v), while this value decreased to 0·015%, after encapsulation of EO into nanoliposomes. Furthermore, subinhibitory concentrations of liposomal EO (50 and 75% MIC) had significantly higher inhibitory effect on Stx2 titre than its free form (P < 0·05). Sub-MICs of nanoencapsulated EO also showed a better activity in reduction of Stx2A gene expression than free EO. Using 75% MIC of nanoliposomal EO, the relative transcriptional level of Stx2A gene was decreased from 0·721 to 0·646. CONCLUSIONS: The findings of present study suggest that application of nanoliposomes can improve the antibacterial effect of EOs like ZMEO. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to the enhancement of antimicrobial activity, nanoencapsulation of plant EOs and extracts may increase their commercial application not only in food area but also in the pharmaceutics, cosmetics and health products.
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Antibacterianos/farmacologia , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/genética , Lamiaceae/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Toxina Shiga II/metabolismo , Antibacterianos/química , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Lipossomos/química , Lipossomos/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/químicaRESUMO
Building restoration represents a fundamental tool to combine the population needs for housing with soil saving. Old buildings offer great possibilities, if we consider that 20% of residential buildings in Italy have been constructed before the beginning of XX century. In order to understand the public health impact of exemptions from hygienic requirements of dwellings, as well as indemnity for abuses, the authors analyse the national legislation on this topic. There is a strong need to update health standards and to rationalize and simplify the regulations, as a fundamental tool for the protection of public health in indoor environment.
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Habitação/normas , Saúde Pública , Habitação/legislação & jurisprudência , Humanos , ItáliaRESUMO
Cosmic strings can give rise to a large variety of interesting astrophysical phenomena. Among them, powerful bursts of gravitational waves (GWs) produced by cusps are a promising observational signature. In this Letter we present a search for GWs from cosmic string cusps in data collected by the LIGO and Virgo gravitational wave detectors between 2005 and 2010, with over 625 days of live time. We find no evidence of GW signals from cosmic strings. From this result, we derive new constraints on cosmic string parameters, which complement and improve existing limits from previous searches for a stochastic background of GWs from cosmic microwave background measurements and pulsar timing data. In particular, if the size of loops is given by the gravitational backreaction scale, we place upper limits on the string tension Gµ below 10(-8) in some regions of the cosmic string parameter space.
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Current housing shortage in Italy is forcing a growing number of individuals to use as living environment spaces that were originally devoted to other purposes. Among such spaces, semi-basements hold a particular relevance because of their specific characteristics and their effects on human health. The authors analyse the relatively scarce legislation about this topic at both national and regional level. The local Building Codes of the ten most populous cities of Italy are reviewed, assessing whether the use of semi-basements as living spaces is allowed and, if so, which restrictions and requirements are imposed. The authors conclude that, on one hand, further research is strongly needed to estimate the amount of exposed population and their health risk, on the other the existing legislation on the topic is often discretionary and deeply unhomogeneous across the country.
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Habitação/legislação & jurisprudência , Habitação/normas , Arquitetura , Humanos , Itália , Fatores de RiscoRESUMO
Recently the Italian Supreme Court has sentenced that garrets not suitable for common usage belong to the owners of the dwellings positioned below. These spaces may be transformed into living areas, which is particularly convenient in this moment of housing shortage. In this study the authors analyze the minimum hygienic requirements for transformed garrets established by each regional law, and underline the considerable differences authorized by the laws. For example, there is a tolerated difference of +/-0,4 m for the the minimum height, and therefore there is a large variability accepted for the volumes of the rooms, namely a tolerated range of 3,6 m3 per capita in single rooms and 2,8 m3 per capita in double rooms; such accepted values are very close to (and sometimes below) the limits for living spaces that have been recommended by the international community. Finally, the authors stress the importance of planning sanitary interventions to protect the health of the inhabitants of those dwellings.
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Habitação/legislação & jurisprudência , Higiene/legislação & jurisprudência , Arquitetura de Instituições de Saúde/legislação & jurisprudência , Arquitetura de Instituições de Saúde/normas , Habitação/normas , Humanos , Itália , Segurança/legislação & jurisprudência , Segurança/normas , Engenharia Sanitária/legislação & jurisprudência , Engenharia Sanitária/normasRESUMO
We report an application of Kalman filtering to the inverted pendulum (IP) of the Virgo gravitational wave interferometer. Using subspace method system identification techniques, we calculated a linear mechanical model of Virgo IP from experimental transfer functions. We then developed a Kalman filter, based on the obtained state space representation, that estimates from open loop time domain data, the state variables of the system. This allows the observation (and eventually control) of every resonance mode of the IP mechanical structure independently.
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Acute fulminant myocarditis is a critical clinical condition with sudden onset of severe congestive heart failure followed by severe haemodynamic deterioration. Instituting early left ventricular support may improve outcome and result in better long term survival. The case of an immunocompromised patient who developed acute fulminant myocarditis in the setting of disseminated mucormycosis is presented.
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Anemia Aplástica/microbiologia , Coração/microbiologia , Mucormicose/patologia , Pericardite/microbiologia , Doença Aguda , Adulto , Anemia Aplástica/fisiopatologia , Encéfalo/microbiologia , Eletrocardiografia , Evolução Fatal , Feminino , Humanos , Hospedeiro Imunocomprometido , Rim/microbiologia , Fígado/microbiologia , Pulmão/microbiologia , Mucormicose/fisiopatologia , Pericardite/fisiopatologia , Pele/microbiologiaRESUMO
OBJECTIVES: Determine the diagnostic performance of thallium-201 myocardial scintigraphy using dipyridamole injection for the detection of coronary heart disease (myocardial ischemia and/or necrosis). Determine for each coronary artery the degree of angiographic stenosis for optimal diagnostic performance. PATIENTS AND METHODS: The study included 309 patients who underwent coronarography within 6 months of the scintigraphy examination. None of the patients experienced a coronary event during this interval. Diagnostic performance of the scintigraphic exploration was compared with angiographic findings (stenosis 70%) used as the gold standard. The degree of angiographic stenosis for optimal scintigraphic performance was determined from the receiver operating characteristic (ROC) curves. RESULTS: The sensitivity of scintigraphy to detect angiographically demonstrated coronary disease was 84% with a specificity of 72%. The positive and negative predictive values were 87% and 66% respectively. Test accuracy was 80%. Sensitivity was better for detecting lesions of the anterior interventricular coronary than for the right coronary or circumflex. In addition, sensitivity varied with the number of vessels involved: 76% for single-vessel disease versus 90% for two- or three-vessel disease. The data analysis also suggested that an angiographic stenosis threshold of 50% provided optimal predictive value for scintigraphy for each of the three vessel territories. An analysis based on maximal stenosis in each patient, notwithstanding the congruency between lesion localization and diseased vessel territories, was found to provide less diagnostic precision. CONCLUSION: Thallium-201 dipyridamole myocardial scintigraphy offers diagnostic performance comparable to that established with thallium-201 scintigraphy performed after exercise alone. Scintigraphic detection of a perfusion defect generally corresponds to an angiographic stenosis of 50%.