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1.
Nature ; 595(7867): 357-358, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34262217
2.
Rep Prog Phys ; 83(2): 026401, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31825901

RESUMEN

Optomechanics is concerned with the use of light to control mechanical objects. As a field, it has been hugely successful in the production of precise and novel sensors, the development of low-dissipation nanomechanical devices, and the manipulation of quantum signals. Micro- and nano-particles levitated in optical fields act as nanoscale oscillators, making them excellent low-dissipation optomechanical objects, with minimal thermal contact to the environment when operating in vacuum. Levitated optomechanics is seen as the most promising route for studying high-mass quantum physics, with the promise of creating macroscopically separated superposition states at masses of 106 amu and above. Optical feedback, both using active monitoring or the passive interaction with an optical cavity, can be used to cool the centre-of-mass of levitated nanoparticles well below 1 mK, paving the way to operation in the quantum regime. In addition, trapped mesoscopic particles are the paradigmatic system for studying nanoscale stochastic processes, and have already demonstrated their utility in state-of-the-art force sensing.

3.
Phys Rev Lett ; 122(20): 200403, 2019 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-31172750

RESUMEN

We develop theoretically and demonstrate experimentally a universal dynamical decoupling method for robust quantum sensing with unambiguous signal identification. Our method uses randomization of control pulses to simultaneously suppress two types of errors in the measured spectra that would otherwise lead to false signal identification. These are spurious responses due to finite-width π pulses, as well as signal distortion caused by π pulse imperfections. For the cases of nanoscale nuclear-spin sensing and ac magnetometry, we benchmark the performance of the protocol with a single nitrogen vacancy center in diamond against widely used nonrandomized pulse sequences. Our method is general and can be combined with existing multipulse quantum sensing sequences to enhance their performance.

4.
Environ Eng Sci ; 32(6): 505-515, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26064039

RESUMEN

During the past decades, pressures on global environment and energy security have led to an increasing demand on renewable energy sources and diversification of the world's energy supply. The Portuguese energy strategy considers the use of Forest Biomass Residues (FBR) to energy as being essential to accomplish the goals established in the National Energy Strategy for 2020. However, despite the advantages pointing to FBR to the energy supply chain, few studies have evaluated the potential impacts on air quality. In this context, a case study was selected to estimate the atmospheric emissions of the FBR to the energy supply chain in Portugal. Results revealed that production, harvesting, and energy conversion processes are the main culprits for the biomass energy supply chain emissions (with a contribution higher than 90%), while the transport processes have a minor importance for all the pollutants. Compared with the coal-fired plants, the FBR combustion produces lower greenhouses emissions, on a mass basis of fuel consumed; the same is true for NOX and SO2 emissions.

5.
Nat Mater ; 12(2): 103-7, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23202370

RESUMEN

Pulsed magnetic resonance allows the quantum state of electronic and nuclear spins to be controlled on the timescale of nanoseconds and microseconds respectively. The time required to flip dilute spins is orders of magnitude shorter than their coherence times, leading to several schemes for quantum information processing with spin qubits. Instead, we investigate 'hybrid nuclear-electronic' qubits consisting of near 50:50 superpositions of the electronic and nuclear spin states. Using bismuth-doped silicon, we demonstrate quantum control over these states in 32 ns, which is orders of magnitude faster than previous experiments using pure nuclear states. The coherence times of up to 4 ms are five orders of magnitude longer than the manipulation times, and are limited only by naturally occurring (29)Si nuclear spin impurities. We find a quantitative agreement between our experiments and an analytical theory for the resonance positions, as well as their relative intensities and Rabi oscillation frequencies. These results bring spins in a solid material a step closer to research on ion-trap qubits.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Bismuto/química , Campos Electromagnéticos , Transporte de Electrón , Electrones , Ensayo de Materiales , Nanopartículas , Teoría Cuántica , Procesamiento de Señales Asistido por Computador , Silicio/química
6.
Lab Hematol ; 18(4): 27-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23253864

RESUMEN

Infantile pyknocytosis (IP) is an under-recognized hematological entity of newborns that can cause a severe neonatal hemolytic anemia. A careful, prompt, and accurate peripheral blood smear examination is essential to establish the diagnosis. Here we describe the clinical features and histological parameters of 1 case of IP. Spontaneous resolution usually occurs by 4 to 6 months, but red blood cell transfusion may be needed if the anemia is severe.


Asunto(s)
Anemia Hemolítica/diagnóstico , Anemia Neonatal/diagnóstico , Eritrocitos Anormales/patología , Anemia Hemolítica/sangre , Anemia Neonatal/sangre , Femenino , Humanos , Recién Nacido
7.
Nat Nanotechnol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956319
8.
An Pediatr (Engl Ed) ; 89(3): 162-169, 2018 Sep.
Artículo en Español | MEDLINE | ID: mdl-29290503

RESUMEN

INTRODUCTION: In Portugal, data on the role of Der p 1 and Der p 2 in patients with house dust mite (HDM) allergy are scarce. Allergen-specific immunotherapy (sIT) is the only treatment that improves symptoms, reduces the need for pharmacological therapy and modifies the natural history of the disease. With this study, the authors aim to understand the local epidemiology and to clarify if the molecular assay of major allergens is advantageous in deciding and/or modifying the decision to initiate sIT in children with clinical indication which are sensitized to Dermatophagoides pteronyssinus. METHODS: Retrospective study with analysis of patients with asthma and/or rhinitis. STUDY PERIOD: January/2013-December/2016. INCLUSION CRITERIA: 1) positive prick-test to Dermatophagoides pteronyssinus; and 2) clinically relevant disease under treatment. Assay Der p 1 and Der p 2 values ≥0.35 kUA/L were considered positive. Statistical significance was set at P<.05. RESULTS: The clinical files of 279 patients. Mean ages 9.55 years (min.4-max.17). Asthma was present in 199 children (71.3%) and rhinitis in 245 (87.8%). Der p 1 and Der p 2 was <0.35kUA/L in 29 (10,4%) patients. The value of Der p 1/Der p 2 correlated with the size of the prick-test papule, the value of the eosinophils and the total IgE. CONCLUSIONS: Der p 1 and Der p 2 are dominant allergens in our population and there may be benefits in determining these molecular allergen levels in patients with a positive prick-test and a clinical indication for sIT prior to a decision of initiating sIT or not.


Asunto(s)
Alérgenos/inmunología , Antígenos Dermatofagoides/inmunología , Proteínas de Artrópodos/inmunología , Asma/inmunología , Cisteína Endopeptidasas/inmunología , Hipersensibilidad/inmunología , Rinitis/inmunología , Asma/complicaciones , Asma/epidemiología , Asma/terapia , Niño , Desensibilización Inmunológica , Femenino , Humanos , Hipersensibilidad/epidemiología , Hipersensibilidad/terapia , Masculino , Portugal/epidemiología , Estudios Retrospectivos , Rinitis/complicaciones , Rinitis/epidemiología , Rinitis/terapia
9.
Rev Soc Bras Med Trop ; 49(4): 477-85, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27598635

RESUMEN

INTRODUCTION: Due to its frequency and morbidity, such as that caused by scorpions have achieved public health importance in certain regions of the world. The present exploratory ecological study aimed to characterize the epidemiological profile and spatial distribution of scorpion stings in Campina Grande, State of Paraíba in Northeastern Brazil. METHODS: Geographical information system techniques were used to record the scorpion stings, and Google Earth software, Track Maker, and ArcGIS 10 Esri were used as geocoding databases. The Moran test was used to evaluate spatial correlation, and the Pearson chi-square test was used to analyze associations between scorpion stings and socioeconomic variables. RESULTS: The study evaluated 1,466 scorpion stings. Envenomations were more frequent among women (n = 908, 61.9%), and most patients were aged 13-28 years (n = 428, 29.2%). The Southern region of the city had the largest number of registered cases (n = 548, 37.4%), followed by the Western region (n = 510, 34.8%). CONCLUSIONS: Spatial analysis of scorpionism revealed an irregular occurrence in Campina Grande. Further, no association was observed between the socioeconomic factors analyzed and the geographic location of the scorpion envenomations. Detection of spatial areas with an increased risk of scorpionism can help prioritize adoption of preventive measures in these regions to reduce the associated incidence and morbidity.


Asunto(s)
Picaduras de Escorpión/epidemiología , Escorpiones , Adolescente , Adulto , Anciano , Animales , Brasil/epidemiología , Niño , Preescolar , Femenino , Sistemas de Información Geográfica , Mapeo Geográfico , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Densidad de Población , Factores Socioeconómicos , Adulto Joven
10.
An. pediatr. (2003. Ed. impr.) ; 89(3): 162-169, sept. 2018. tab, graf
Artículo en Español | IBECS (España) | ID: ibc-177087

RESUMEN

INTRODUCCIÓN: En Portugal los datos del papel de Der p 1 y Der p 2 en niños con alergia al ácaro del polvo son escasos. La inmunoterapia específica (IE) con alérgenos es el único tratamiento que mejora los síntomas, reduce la necesidad de terapia farmacológica y modifica la historia natural de la enfermedad. Con este trabajo, los autores estudian la epidemiología local y buscan aclarar si el análisis molecular de los alérgenos principales es una ventaja para decidir y/o modificar la decisión de iniciar IE en niños con indicación clínica y sensibilizados a Dermatophagoides pteronyssinus. MÉTODOS: Estudio retrospectivo de los niños con asma y/o rinitis. Período de estudio: enero de 2013 a diciembre de 2016. CRITERIOS DE INCLUSIÓN: 1) prick-test positivo a Dermatophagoides pteronyssinus; y 2) enfermedad clínicamente relevante bajo tratamiento. Los valores de Der p 1 y Der p 2 ≥ 0,35kUA/l fueron considerados positivos. La significación estadística se estableció en p < 0,05. RESULTADOS: Se incluyeron en el estudio 279 pacientes. Edad media 9,55 años (min. 4-máx. 17). El asma estuvo presente en 199 niños (71,3%) y rinitis en 245 (87,8%). Der p 1 y Der p 2 fue<0,35kUA/l en 29 (10,4%) pacientes. Der p 1/Der p 2 se correlacionó con el tamaño de la pápula de prick-test, con el valor de los eosinófilos y la IgE total. CONCLUSIONES: Der p 1 y Der p 2 son alérgenos dominantes en nuestra población y puede haber beneficios en la determinación de estos niveles de alérgenos moleculares en pacientes con un prick-test positivo e indicación clínica para IE


INTRODUCTION: In Portugal, data on the role of Der p 1 and Der p 2 in patients with house dust mite (HDM) allergy are scarce. Allergen-specific immunotherapy (sIT) is the only treatment that improves symptoms, reduces the need for pharmacological therapy and modifies the natural history of the disease. With this study, the authors aim to understand the local epidemiology and to clarify if the molecular assay of major allergens is advantageous in deciding and/or modifying the decision to initiate sIT in children with clinical indication which are sensitized to Dermatophagoides pteronyssinus. METHODS: Retrospective study with analysis of patients with asthma and/or rhinitis. Study period: January/2013-December/2016. Inclusion criteria: 1) positive prick-test to Dermatophagoides pteronyssinus; and 2) clinically relevant disease under treatment. Assay Der p 1 and Der p 2 values ≥ 0.35 kUA/L were considered positive. Statistical significance was set at P < .05. RESULTS: The clinical files of 279 patients. Mean ages 9.55 years (min.4-max.17). Asthma was present in 199 children (71.3%) and rhinitis in 245 (87.8%). Der p 1 and Der p 2 was < 0.35kUA/L in 29 (10,4%) patients. The value of Der p 1/Der p 2 correlated with the size of the prick-test papule, the value of the eosinophils and the total IgE. CONCLUSIONS: Der p 1 and Der p 2 are dominant allergens in our population and there may be benefits in determining these molecular allergen levels in patients with a positive prick-test and a clinical indication for sIT prior to a decision of initiating sIT or not


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Niño , Adolescente , Asma/inmunología , Asma/terapia , Alérgenos/inmunología , Antígenos Dermatofagoides/inmunología , Rinitis/inmunología , Desensibilización Inmunológica/métodos , Inmunoterapia/métodos , Estudios Retrospectivos , Hipersensibilidad/inmunología , Pruebas Cutáneas
11.
Rev. Soc. Bras. Med. Trop ; 49(4): 477-485, July-Aug. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-792790

RESUMEN

Abstract: INTRODUCTION: Due to its frequency and morbidity, such as that caused by scorpions have achieved public health importance in certain regions of the world. The present exploratory ecological study aimed to characterize the epidemiological profile and spatial distribution of scorpion stings in Campina Grande, State of Paraíba in Northeastern Brazil. METHODS: Geographical information system techniques were used to record the scorpion stings, and Google Earth software, Track Maker, and ArcGIS 10 Esri were used as geocoding databases. The Moran test was used to evaluate spatial correlation, and the Pearson chi-square test was used to analyze associations between scorpion stings and socioeconomic variables. RESULTS: The study evaluated 1,466 scorpion stings. Envenomations were more frequent among women (n = 908, 61.9%), and most patients were aged 13-28 years (n = 428, 29.2%). The Southern region of the city had the largest number of registered cases (n = 548, 37.4%), followed by the Western region (n = 510, 34.8%). CONCLUSIONS: Spatial analysis of scorpionism revealed an irregular occurrence in Campina Grande. Further, no association was observed between the socioeconomic factors analyzed and the geographic location of the scorpion envenomations. Detection of spatial areas with an increased risk of scorpionism can help prioritize adoption of preventive measures in these regions to reduce the associated incidence and morbidity.


Asunto(s)
Humanos , Animales , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto , Anciano , Adulto Joven , Escorpiones , Picaduras de Escorpión/epidemiología , Factores Socioeconómicos , Brasil/epidemiología , Incidencia , Densidad de Población , Sistemas de Información Geográfica , Mapeo Geográfico , Persona de Mediana Edad
12.
Ther Drug Monit ; 27(5): 601-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16175133

RESUMEN

A validated method for on-line solid-phase extraction coupled with high-performance liquid chromatography tandem mass spectrometry (SPE-HPLC-MS-MS) is described for the quantification of bromazepam in human plasma. The method involves a dilution of 300 muL of plasma with 100 muL of carbamazepine (2.5 ng/mL), used as internal standard, vortex-mixing, centrifugation, and injection of 100 muL of the supernate. The analytes were ionized using positive electrospray mass spectrometry then detected by multiple reaction monitoring (MRM). The m/z transitions 316-->182 (bromazepam) and 237-->194 (carbamazepine) were used for quantification. The calibration curve was linear from 1 ng/mL (limit of quantification) to 200 ng/mL. The retention times of bromazepam and carbamazepine were 2.6 and 3.2 minutes, respectively. The intraday and interday precisions were 3.43%-15.45% and 5.2%-17%, respectively. The intraday and interday accuracy was 94.00%-103.94%. This new automated method has been successfully applied in a bioequivalence study of 2 tablet formulations of 6 mg bromazepam: Lexotan(R) from Produtos Roche Químicos e Farmacêuticos SA, Rio de Janeiro, Brazil (reference) and test formulation from Laboratórios Biosintética Ltda, São Paulo, Brazil. Because the 90% CI of geometric mean ratios between reference and test were completely included in the 80%-125% interval, the 2 formulations were considered bioequivalent. The comparison of different experimental conditions for establishing a dissolution profile in vitro along with our bioavailability data further allowed us to propose rationally based experimental conditions for a dissolution test of bromazepam tablets, actually lacking a pharmacopeial monograph.


Asunto(s)
Bromazepam/sangre , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Adulto , Área Bajo la Curva , Bromazepam/aislamiento & purificación , Bromazepam/farmacocinética , Humanos , Masculino , Persona de Mediana Edad , Control de Calidad , Solubilidad , Equivalencia Terapéutica
13.
Arq. bras. med ; 60(6): 501-3, nov.-dez. 1986. tab, ilus
Artículo en Portugués | LILACS | ID: lil-37948

RESUMEN

Estudaram-se 22 pacientes de ambos os sexos, entre 39 e 78 anos, atendidos como quadro clínico de crise hipertensiva e tratados com a associaçäo dinitrato de isosorbitol sublingual associado a aminofilina intravenosa. Os níveis de pressäo arterial diminuíram, evidenciando um potente efeito vasodilatador, resultante desta associaçäo medicamentosa. O uso dessa associaçäo é justificado por serem os medicamentos de fácil acesso e manipulaçäo, farmacocinética e farmacodinâmica bastante estudados, bem como toxicidade e efeitos colaterais conhecidos


Asunto(s)
Adulto , Persona de Mediana Edad , Humanos , Masculino , Femenino , Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Nitratos/uso terapéutico , Xantinas/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Quimioterapia Combinada
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