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1.
Food Res Int ; 168: 112767, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120217

RESUMO

Beehive derivatives, including honeybee pollen (HBP), have been extensively studied for their beneficial health properties and potential therapeutic use. Its high polyphenol content gives it excellent antioxidant and antibacterial properties. Today its use is limited due to poor organoleptic properties, low solubility, stability, and permeability under physiological conditions. A novel edible multiple W/O/W nanoemulsion (BP-MNE) to encapsulate the HBP extract was designed and optimized to overcome these limitations. The new BP-MNE has a small size (∼100 nm), a zeta potential greater than +30 mV, and efficiently encapsulated phenolic compounds (∼82%). BP-MNE stability was measured under simulated physiological conditions and storage conditions (4 months); in both cases, stability was promoted. The formulation's antioxidant and antibacterial (Streptococcus pyogenes) activity was analyzed, obtaining a higher effect than the non-encapsulated compounds in both cases. In vitro permeability was tested, observing a high permeability of the phenolic compounds when they are nanoencapsulated. With these results, we propose our BP-MNE as an innovative solution to encapsulate complex matrices, such as HBP extract, as a platform to develop functional foods.


Assuntos
Antioxidantes , Fenóis , Abelhas , Animais , Antioxidantes/farmacologia , Chile , Antibacterianos/farmacologia , Permeabilidade , Pólen
2.
Phys Rev Lett ; 128(9): 091302, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302802

RESUMO

We search for the signature of parity-violating physics in the cosmic microwave background, called cosmic birefringence, using the Planck data release 4. We initially find a birefringence angle of ß=0.30°±0.11° (68% C.L.) for nearly full-sky data. The values of ß decrease as we enlarge the Galactic mask, which can be interpreted as the effect of polarized foreground emission. Two independent ways to model this effect are used to mitigate the systematic impact on ß for different sky fractions. We choose not to assign cosmological significance to the measured value of ß until we improve our knowledge of the foreground polarization.

3.
Rev Esp Anestesiol Reanim (Engl Ed) ; 69(1): 48-53, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35033481

RESUMO

Patients with COVID-19 who are admitted to intensive care unit (ICU) are at high risk of developing secondary infections, including invasive fungal infections such as invasive pulmonary aspergillosis (IPA). The main purpose was to analyse the putative COVID-19 Associated Pulmonary Aspergillosis (CAPA) patients in our setting. In these patients, we performed mycological culture in bronchoalveolar lavage (BAL) for isolation of Aspergillus sp. We followed the AspICU algorithm to diagnose putative IPA. Moreover, we considered relevant the positivity of Galactomannan in BAL. We diagnosed putative IPA in 3 patients. The common features of these 3 patients were: more than 21 days of stay in ICU, severe acute respiratory distress syndrome (ARDS) and treatment with steroids (1 mg/kg per day). Therefore, CAPA has to be systematically considered although a new algorithm to diagnose it is needed to treat patients in early stages in order to avoid catastrophic outcomes.


Assuntos
COVID-19 , Aspergilose Pulmonar Invasiva , Aspergilose Pulmonar , Aspergillus , Humanos , Aspergilose Pulmonar Invasiva/diagnóstico , Aspergilose Pulmonar Invasiva/tratamento farmacológico , SARS-CoV-2
4.
Rev. esp. anestesiol. reanim ; 69(1): 48-53, Ene 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-206698

RESUMO

Los pacientes con COVID-19 que ingresan en una unidad de cuidados intensivos (UCI), tienen un alto riesgo de desarrollar infecciones secundarias, incluyendo infecciones fúngicas invasivas como aspergilosis pulmonar invasiva (API). El objetivo principal fue el análisis de los casos con sospecha de COVID-19 Associated Pulmonary Aspergillosis (CAPA) en nuestra unidad. En estos pacientes realizamos cultivo micológico en el lavado broncoalveolar como métodos de aislamiento de Aspergillus sp. Se siguió el algoritmo AspICU para establecer el diagnóstico de API probable. Además, considerando también relevante la positividad del antígeno de galactomanano. Se confirmó API probable en 3 de ellos. Los 3 pacientes permanecieron ingresados más de 21 días por SDRA grave, y recibieron corticoterapia (1mg/kg/día). Por tanto, la CAPA se debe considerar de forma sistemática, aunque se necesita un nuevo algoritmo diagnóstico que permita tratamiento precoz por las consecuencias deletéreas que puede implicar en los pacientes críticos.(AU)


Patients with COVID-19 who are admitted to intensive care unit (ICU) are at high risk of developing secondary infections, including invasive fungal infections such as invasive pulmonary aspergillosis (IPA). The main purpose was to analyse the putative COVID-19 Associated Pulmonary Aspergillosis (CAPA) patients in our setting. In these patients, we performed mycological culture in bronchoalveolar lavage (BAL) for isolation of Aspergillus sp. We followed the AspICU algorithm to diagnose putative IPA. Moreover, we considered relevant the positivity of galactomannan in BAL. We diagnosed putative IPA in 3 patients. The common features of these 3 patients were: more than 21 days of stay in ICU, severe acute respiratory distress syndrome (ARDS) and treatment with steroids (1mg/kg per day). Therefore, CAPA has to be systematically considered although a new algorithm to diagnose it is needed to treat patients in early stages in order to avoid catastrophic outcomes.(AU)


Assuntos
Humanos , Aspergilose Pulmonar Invasiva , Betacoronavirus , Pandemias , Unidades de Terapia Intensiva , Pacientes Internados , Tratamento Farmacológico , Anestesiologia , Espanha , Reanimação Cardiopulmonar
5.
Rev Esp Anestesiol Reanim ; 69(1): 48-53, 2022 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-33994593

RESUMO

Patients with COVID-19 who are admitted to intensive care unit (ICU) are at high risk of developing secondary infections, including invasive fungal infections such as invasive pulmonary aspergillosis (IPA). The main purpose was to analyse the putative COVID-19 Associated Pulmonary Aspergillosis (CAPA) patients in our setting. In these patients, we performed mycological culture in bronchoalveolar lavage (BAL) for isolation of Aspergillus sp. We followed the AspICU algorithm to diagnose putative IPA. Moreover, we considered relevant the positivity of galactomannan in BAL. We diagnosed putative IPA in 3 patients. The common features of these 3 patients were: more than 21 days of stay in ICU, severe acute respiratory distress syndrome (ARDS) and treatment with steroids (1 mg/kg per day). Therefore, CAPA has to be systematically considered although a new algorithm to diagnose it is needed to treat patients in early stages in order to avoid catastrophic outcomes.

6.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34565575

RESUMO

Patients with COVID-19 who are admitted to intensive care unit (ICU) are at high risk of developing secondary infections, including invasive fungal infections such as invasive pulmonary aspergillosis (IPA). The main purpose was to analyse the putative COVID-19 Associated Pulmonary Aspergillosis (CAPA) patients in our setting. In these patients, we performed mycological culture in bronchoalveolar lavage (BAL) for isolation of Aspergillus sp. We followed the AspICU algorithm to diagnose putative IPA. Moreover, we considered relevant the positivity of galactomannan in BAL. We diagnosed putative IPA in 3 patients. The common features of these 3 patients were: more than 21 days of stay in ICU, severe acute respiratory distress syndrome (ARDS) and treatment with steroids (1mg/kg per day). Therefore, CAPA has to be systematically considered although a new algorithm to diagnose it is needed to treat patients in early stages in order to avoid catastrophic outcomes.

7.
Rehabilitación (Madr., Ed. impr.) ; 49(3): 162-171, jul.-sept. 2015. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-136891

RESUMO

Introducción. Los pacientes intervenidos quirúrgicamente con disección axilar supervivientes de cáncer de mama, a partir de las recomendaciones actuales, restringen su actividad física por miedo e incertidumbre a padecer linfedema secundario, lo que puede limitar su recuperación física y psicosocial. En este estudio, observamos los efectos de un programa de entrenamiento controlado, que incluyó ejercicios con levantamiento de pesos. Material y métodos. Ensayo clínico prospectivo abierto y controlado. Se seleccionaron 22 pacientes diagnosticados de cáncer de mama, con disección axilar de, al menos, un nódulo linfático, con o sin diagnóstico de linfedema. El grupo intervención (grupo de actividad física con pesas, GAFP, n=11) mantuvo su estilo de vida habitual, incorporando un protocolo terapéutico de ejercicios bisemanal diseñado por fisioterapeutas, que incluyó levantamiento de pesos de forma controlada y progresiva, realizado siempre bajo su supervisión. El grupo control (GC, n=11) mantuvo su estilo de vida sin cambios durante las 6 semanas de duración del estudio (febrero-marzo de 2013). Se valoraron el volumen del brazo (midiendo la circunferencia de cada brazo), las sensaciones de dolor y pesadez del brazo mediante la Escala Visual Analógica (EVA), el índice de masa corporal (BMI) y la calidad de vida (FACT-B+4), Resultados. Ninguna de las participantes en el grupo de intervención experimentó un aumento de los síntomas. No hubo diferencias significativas entre ambos grupos, aunque se advirtió una tendencia (p = 0,341) hacia el descenso del volumen del brazo afecto en los pacientes del grupo GAFP. Conclusiones. De acuerdo con estudios previos, es segura la realización de un protocolo de ejercicios que incluya levantamiento de pesos, en un entorno controlado y progresivo (AU)


Introduction. In breast cancer survivors who have undergone axillary dissection, current recommendations advise restricting physical activity due to the risk of secondary lymphedema, which may limit these patients’ physical and psychosocial recovery. In this study, we examined the effects of a controlled training program that included weightlifting exercises. Material and methods. An open, prospective, controlled clinical trial was carried out that included a control and an intervention group. We selected 22 patients with a diagnosis of breast cancer and dissection of at least one axillary lymph node, with or without a diagnosis of lymphedema. An intervention group (group of physical activity weights, n=11) maintained their usual lifestyle, incorporating a therapeutic protocol designed by physiotherapists, consisting of twice-weekly exercises that included weightlifting in controlled and progressive sessions, always under supervision. A control group (n=11) maintained their lifestyle unchanged for the 6-week study (February-March 2013). We also assessed arm volume (measurement of the circumference of each arm, sensations of pain and heaviness [Visual Analog Scale], body mass index [BMI], and quality of life [FACT-B +4]). Results. None of the participants in the intervention group had symptom exacerbation or a diagnosis of lymphedema. There were no significant differences between the 2 groups, although a trend (P=.341) toward a decrease in the volume of the affected arm was noted in patients in the intervention group. Conclusions. Consistent with previous studies, this study confirms the safety of an exercise protocol that included weight lifting in a progressive and controlled environment (AU)


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Exercício Físico/fisiologia , Levantamento de Peso/educação , Levantamento de Peso/fisiologia , Dissecação/reabilitação , Excisão de Linfonodo/reabilitação , Excisão de Linfonodo , Modalidades de Fisioterapia , Qualidade de Vida , Estudos Prospectivos , Índice de Massa Corporal , Inquéritos e Questionários , Neoplasias da Mama/complicações , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/reabilitação
8.
J Mech Behav Biomed Mater ; 51: 328-36, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282075

RESUMO

The strength of soft tissues is due mainly to collagen fibers. In most collagenous tissues, the arrangement of the fibers is random, but has preferred directions. The random arrangement makes it difficult to make deterministic predictions about the starting process of fiber breaking under tension. When subjected to tensile stress the fibers are progressively straighten out and then start to be stretched. At the beginning of fiber breaking, some of the fibers reach their maximum tensile strength and break down while some others remain unstressed (this latter fibers will assume then bigger stress until they eventually arrive to their failure point). In this study, a sample of human esophagi was subjected to a tensile breaking of fibers, up to the complete failure of the specimen. An experimental setup using Acoustic Emission to detect the elastic energy released is used during the test to detect the location of the emissions and the number of micro-failures per time unit. The data were statistically analyzed in order to be compared to a stochastic model which relates the level of stress in the tissue and the probability of breaking given the number of previously broken fibers (i.e. the deterioration in the tissue). The probability of a fiber breaking as the stretch increases in the tissue can be represented by a non-homogeneous Markov process which is the basis of the stochastic model proposed. This paper shows that a two-parameter model can account for the fiber breaking and the expected distribution for ultimate stress is a Fréchet distribution.


Assuntos
Acústica , Modelos Estatísticos , Estresse Mecânico , Elasticidade , Esôfago/citologia , Humanos , Teste de Materiais , Pessoa de Meia-Idade , Processos Estocásticos , Resistência à Tração
9.
An Sist Sanit Navar ; 37(1): 91-8, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-24871114

RESUMO

Isolation of the airway sometimes determines the survival or death of the patient. To anticipate the presence of a difficult airway (DA) there are a number of indicators that are validated for hospitals: Mallampati, sternum and thyromental distance, interdental distance and Cormack grade. The aim of this study is to evaluate the use of these indicators in the ambulatory setting and to know the incidence of DA. This data was collected from 324 intubations. Most patients were males (65.2%). The average age of the population was 63 years and no significant difference in age between DA and DA was found. A DA presence of 20.7% was objectified and an alternative device utilization of 21.4%. The thyromental distance was abnormal in 59% of patients and sternomentonal distance in 56.4% but neither showed an association with the presence of DA (p = 0.681 and p = 0.415 respectively). Interdental distance was less than 3 cm if presence is associated with DA (p = 0.005). The sensitivity and specificity of all measures are low. According to our series the sternum and thyromental distance are not useful in the ambulatory setting, but interdental distance is useful for predicting a DA.


Assuntos
Manuseio das Vias Aéreas , Assistência Ambulatorial , Manuseio das Vias Aéreas/estatística & dados numéricos , Técnicas de Apoio para a Decisão , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
12.
Rev Esp Anestesiol Reanim ; 56(4): 217-21, 2009 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-19537261

RESUMO

OBJECTIVES: To study muscle weakness caused by low doses of rocuronium and rocuronium intolerance in healthy volunteers, with the general aim of producing brief skeletal-muscle relaxation that would have potential applications in clinical situations. PATIENTS AND METHODS: After receiving authorization from the clinical research ethics committee of our hospital, we set out to study the effects on subjective and objective muscle strength of injecting 3 doses of rocuronium (0.1 mg x kg(-1), 0.05 mg x kg(-2), and 0.075 mg x kg(-1)) in healthy volunteers, each dose on a different day. Objective muscle strength was measured using a hand dynamometer. We also recorded the development of expected adverse effects (diplopia, dysarthria, and dysphagia). RESULTS: Five volunteers (all authors) were studied. In the first subject, the dose of 0.1 mg x kg(-1) of rocuronium was unsatisfactory because it was too strong, causing extreme skeletal-muscle weakness and discomfort due to diplopia, dysarthria, and dysphagia. The dose of 0.05 mg x kg(-1) was well tolerated but caused no subjective feeling of weakness or any effect measurable on dynamometry. These doses were not administered to the other subjects. In the 4 remaining volunteers, the dose of 0.075 mg x kg(-1) caused a brief feeling of muscle weakness that was considered to be acceptable, though the findings were compromised by 2 technically defective baseline dynamometry readings. The volunteers also reported brief, mild discomfort, principally due to dysphagia. CONCLUSIONS: Doses of 0.075 mg x kg(-1) of rocuronium in healthy awake subjects breathing spontaneously are acceptably tolerated and cause brief muscle weakness that may be of use in situations that require skeletal muscle relaxation at specific moments.


Assuntos
Androstanóis/farmacologia , Debilidade Muscular/induzido quimicamente , Fármacos Neuromusculares não Despolarizantes/farmacologia , Adulto , Androstanóis/administração & dosagem , Androstanóis/efeitos adversos , Diplopia/induzido quimicamente , Diplopia/psicologia , Relação Dose-Resposta a Droga , Disartria/induzido quimicamente , Disartria/psicologia , Força da Mão , Humanos , Masculino , Debilidade Muscular/psicologia , Fármacos Neuromusculares não Despolarizantes/administração & dosagem , Fármacos Neuromusculares não Despolarizantes/efeitos adversos , Aceitação pelo Paciente de Cuidados de Saúde , Respiração , Rocurônio , Vigília , Adulto Jovem
13.
Rev. esp. anestesiol. reanim ; 56(4): 217-221, abr. 2009.
Artigo em Espanhol | IBECS | ID: ibc-72306

RESUMO

OBJETIVOS: Investigar en voluntarios sanos la debilidadmuscular producida por dosis bajas de rocuronio ysu tolerancia, con la idea general de producir una breverelajación muscular esquelética potencialmente aplicableen situaciones clínicas.PACIENTES Y MÉTODOS: Tras autorización del Comitéde Ética e Investigación Clínica de nuestro hospital, nospropusimos estudiar en voluntarios sanos los efectos detres dosis de rocuronio (0,1, 0,05 ó 0,075mg Kg-1), administradasen diferentes días, sobre la fuerza muscular anivel subjetivo y objetivo (medida con un dinamómetrode puño), y la aparición de efectos adversos previstos(diplopia, disartria, disfagia).RESULTADOS: Se incluyeron cinco voluntarios. En elprimer sujeto la dosis de 0,1 mg Kg-1 de rocuronio resultóinadecuada por exceso de efecto (debilidad extrema dela musculatura esquelética; experiencia desagradablepor diplopia, disartria y disfagia) y la dosis de 0,05 mgKg-1 fue bien tolerada, pero sin sensación de debilidad niefectos apreciables sobre la dinamometría. Estas dosdosis no se administraron al resto de sujetos. En losotros cuatro voluntarios, la dosis de 0,075 mg Kg-1 produjouna breve sensación de debilidad muscular consideradaaceptable (aunque los resultados estuvieroninterferidos por dos dinamometrías basales deficientestécnicamente), con leve y breve sensación desagradable(por disfagia principalmente).CONCLUSIONES: Dosis de rocuronio de 0,075 mg Kg-1en sujetos sanos conscientes y respiración espontáneason aceptablemente toleradas y producen un breve estadode debilidad muscular que podría ser de utilidad ensituaciones que precisen momentos puntuales de relajaciónmuscular esquelética(AU)


OBJETIVES: To study muscle weakness caused by lowdoses of rocuronium and rocuronium intolerance inhealthy volunteers, with the general aim of producingbrief skeletal-muscle relaxation that would havepotential applications in clinical situations.PATIENTS AND METHODS: After receiving authorizationfrom the clinical research ethics committee of ourhospital, we set out to study the effects on subjective andobjective muscle strength of injecting 3 doses ofrocuronium (0.1 mg.kg-1, 0.05 mg.kg-1, and 0.075 mg.kg-1)in healthy volunteers, each dose on a different day.Objective muscle strength was measured using a handdynamometer. We also recorded the development ofexpected adverse effects (diplopia, dysarthria, anddysphagia).RESULTS: Five volunteers (all authors) were studied.In the first subject, the dose of 0.1 mg.kg-1 of rocuroniumwas unsatisfactory because it was too strong, causingextreme skeletal-muscle weakness and discomfort due todiplopia, dysarthria, and dysphagia. The dose of 0.05mg.kg-1 was well tolerated but caused no subjectivefeeling of weakness or any effect measurable ondynamometry. These doses were not administered to theother subjects. In the 4 remaining volunteers, the dose of0.075 mg.kg-1 caused a brief feeling of muscle weaknessthat was considered to be acceptable, though thefindings were compromised by 2 technically defectivebaseline dynamometry readings. The volunteers alsoreported brief, mild discomfort, principally due todysphagia.CONCLUSIONS: Doses of 0.075 mg.kg-1 of rocuronium inhealthy awake subjects breathing spontaneously areacceptably tolerated and cause brief muscle weaknessthat may be of use in situations that require skeletalmuscle relaxation at specific moments(AU)


Assuntos
Humanos , Masculino , Adulto , Androstanóis/farmacologia , Debilidade Muscular/induzido quimicamente , /administração & dosagem , /efeitos adversos , /farmacologia , Androstanóis/administração & dosagem , Androstanóis/efeitos adversos , Diplopia/induzido quimicamente , Diplopia/psicologia , Relação Dose-Resposta a Droga , Disartria/induzido quimicamente , Disartria/psicologia , Debilidade Muscular/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Vigília
14.
Rev Esp Anestesiol Reanim ; 56(1): 31-42, 2009 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-19284126

RESUMO

Artificial nutrition support forms part of the basic care of critical patients. Enteral feeding has been shown to be better than total parenteral nutrition at improving morbidity (infectious complications) and reducing the length of hospital stays, number of days with mechanical ventilation, and costs. As with any other treatment, enteral feeding has associated complications and side effects which should be understood and treated in order to obtain the greatest benefit from it and reduce possible adverse effects. In this review, we attempt to provide a practical summary of the use of enteral feeding in critical patients. We cover the management of the most frequent associated complications, based on new studies and current scientific evidence. The review is intended to serve as a practice guide for the routine care of severely ill patients.


Assuntos
Cuidados Críticos/métodos , Nutrição Enteral , Doença Aguda , Injúria Renal Aguda/terapia , Calorimetria Indireta , Contraindicações , Nutrição Enteral/efeitos adversos , Nutrição Enteral/métodos , Alimentos Formulados/efeitos adversos , Alimentos Formulados/análise , Gastroenteropatias/etiologia , Gastroenteropatias/prevenção & controle , Gastroenteropatias/terapia , Humanos , Sistema Imunitário/efeitos dos fármacos , Jejuno , Falência Hepática/terapia , Necessidades Nutricionais , Pancreatite/terapia , Pneumonia Aspirativa/etiologia , Pneumonia Aspirativa/prevenção & controle , Sepse/terapia , Estômago , Ferimentos e Lesões/terapia
15.
Rev. esp. anestesiol. reanim ; 56(1): 31-42, ene. 2009. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-59468

RESUMO

El soporte nutricional artificial forma parte del cuidadobásico del paciente crítico. La nutrición enteral(NE) se ha mostrado superior a la nutrición parenteraltotal (NPT) en la mejoría de la morbilidad (complicacionesinfecciosas), y en la reducción de la estancia hospitalaria,días de ventilación mecánica y costes.Como cualquier otro tratamiento, la NE no está exentade complicaciones y efectos secundarios, que debemosconocer y tratar para obtener el máximo beneficio deésta y disminuir en lo posible los efectos adversos.En esta revisión intentamos resumir de manera prácticael uso de la NE en el paciente crítico, así como elmanejo de las complicaciones más frecuentes que podemosencontrar en relación con dicha nutrición en base alas nuevas publicaciones y la evidencia científica existente,de manera que pueda servir como Guía de actuaciónal profesional en la asistencia diaria al paciente gravementeenfermo (AU)


Artificial nutrition support forms part of thebasic care of critical patients. Enteral feeding has beenshown to be better than total parenteral nutrition atimproving morbidity (infectious complications) andreducing the length of hospital stays, number of days withmechanical ventilation, and costs. As with any othertreatment, enteral feeding has associated complicationsand side effects which should be understood and treatedin order to obtain the greatest benefit from it and reducepossible adverse effects. In this review, we attempt toprovide a practical summary of the use of enteral feedingin critical patients. We cover the management of the mostfrequent associated complications, based on new studiesand current scientific evidence. The review is intended toserve as a practice guide for the routine care of severely illpatients (AU)


Assuntos
Humanos , Nutrição Enteral/métodos , Estado Terminal/terapia , Cuidados Críticos/métodos , Nutrição Enteral , Guias de Prática Clínica como Assunto , Estado Nutricional
17.
Science ; 318(5856): 1612-4, 2007 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-17962521

RESUMO

The Cosmic Microwave Background provides our most ancient image of the universe and our best tool for studying its early evolution. Theories of high-energy physics predict the formation of various types of topological defects in the very early universe, including cosmic texture, which would generate hot and cold spots in the Cosmic Microwave Background. We show through a Bayesian statistical analysis that the most prominent 5 degrees -radius cold spot observed in all-sky images, which is otherwise hard to explain, is compatible with having being caused by a texture. From this model, we constrain the fundamental symmetry-breaking energy scale to be (0) approximately 8.7 x 10(15) gigaelectron volts. If confirmed, this detection of a cosmic defect will probe physics at energies exceeding any conceivable terrestrial experiment.

18.
Phys Rev Lett ; 96(15): 151303, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16712146

RESUMO

We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet decomposition of the CMB signal on the sphere. The analysis of the first-year Wilkinson Microwave Anisotropy Probe data identifies a mean preferred plane with a normal direction close to the CMB dipole axis, and a mean preferred direction in this plane, very close to the ecliptic poles axis. Previous statistical anisotropy results are thereby synthesized, but further analyses are still required to establish their origin.

19.
Science ; 279(5353): 1011-4, 1998 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-9461429

RESUMO

An optical transient within the error box of the gamma ray burst GRB 970508 was imaged 4 hours after the event. It displayed a strong ultraviolet excess, and reached maximum brightness 2 days later. The optical spectra did not show any emission lines, and no variations on time scales of minutes were observed for 1 hour during the decline phase. According to the fireball and afterglow models, the intensity should rise monotonically before the observed optical maximum, but the data indicate that another physical mechanism may be responsible for the constant phase seen during the first hours after the burst.

20.
Ann N Y Acad Sci ; 688: 827-9, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26469508
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