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Light-sheet fluorescence microscopy has greatly improved the speed and overall photostability of optically sectioning cellular and multi-cellular specimens. Similar gains have also been conferred by light-sheet Raman imaging; these schemes, however, rely on diffraction limited Gaussian beams that hinder the uniformity and size of the imaging field-of-view, and, as such, the resulting throughput rates. Here, we demonstrate that a digitally scanned Airy beam increases the Raman imaging throughput rates by more than an order of magnitude than conventional diffraction-limited beams. Overall, this, spectrometer-less, approach enabled 3D imaging of microparticles with high contrast and 1 µm axial resolution at 300 msec integration times per plane and orders of magnitude lower irradiation density than coherent Raman imaging schemes. We detail the apparatus and its performance, as well as its compatibility with fluorescence light-sheet and quantitative-phase imaging towards rapid and low phototoxicity multimodal imaging.
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Aumento da Imagem/métodos , Iluminação/métodos , Microscopia/métodos , Análise Espectral Raman/métodos , Dimetilpolisiloxanos , Microscopia de Fluorescência/métodosRESUMO
Cytoplasmic dynein is an important molecular motor involved in the transport of vesicular and macromolecular cargo along microtubules in cells, often in conjunction with kinesin motors. Dynein is larger and more complex than kinesin and the mechanism and regulation of its movement is currently the subject of intense research. While it was believed for a long time that dynein motors are relatively weak in terms of the force they can generate, recent studies have shown that interactions with regulatory proteins confer large stall forces comparable to those of kinesin. This paper reports on a theoretical study which suggests that these large stall forces may be the result of an emergent, ATP-dependent, bistability resulting in a dynamic catch-bonding behavior that can cause the motor to switch between high and low load-force states.
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Dineínas do Citoplasma/metabolismo , Trifosfato de Adenosina/metabolismo , Cinética , Modelos BiológicosAssuntos
Carcinoma de Célula de Merkel , Imunoconjugados , Neoplasias Cutâneas , Biomarcadores Tumorais , Carcinoma de Célula de Merkel/tratamento farmacológico , Carcinoma de Célula de Merkel/patologia , Humanos , Imunoconjugados/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologiaRESUMO
Preclinical pediatric emergencies are rare events and are therefore often associated with stress and uncertainty for emergency medical service personnel. To ensure adequate treatment of pediatric patients a variety of different cognitive aids exist (e.g. books, apps, rulers, weight-adapted bag systems). Especially the size specifications of the medical equipment and the dosage of emergency medication are individually very different in children and are dependent on parameters, such as body height and weight. Therefore, cognitive aids often enable length measurement whereby it is possible to draw conclusions on body weight for calculating the child's medication dosage. These aids may help to avoid the wrong medication dose or the wrong therapy of children but uncritical and untrained usage of these aids carries a potential risk of mistakes. This recommendation gives an overview of the general requirements and different problems of cognitive aids and should help improve the general framework and the rational basis for the use and further development of cognitive aids in emergency medicine.
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Recursos Audiovisuais/estatística & dados numéricos , Serviços Médicos de Emergência/métodos , Pediatria/métodos , Adolescente , Estatura , Peso Corporal , Criança , Pré-Escolar , Consenso , Humanos , Lactente , Recém-Nascido , Erros de Medicação/prevenção & controle , Preparações Farmacêuticas/administração & dosagemRESUMO
BACKGROUND: Airway management with supraglottic airway devices (SGA) in life-threatening emergencies involving children is becoming increasingly more important. The laryngeal mask (LM) and the laryngeal tube (LT) are devices commonly used for this purpose. This article presents a literature review and consensus statement by various societies on the use of SGA in pediatric emergency medicine. MATERIAL AND METHODS: Literature search in the database PubMed and classification of studies according to the criteria of the Oxford Centre for Evidence-based Medicine levels of evidence. RESULTS: The evidence for successful application of the various types of LM is significantly higher than for LT application. Reports of smaller series of successful applications of LT are currently limited to selected research groups and centers. Insufficient evidence currently exists for the successful application of the LT especially for children below 10 kg body weight and, therefore, its routine use cannot currently be recommended. SGAs used for emergencies should have a possibility for gastric drainage. DISCUSSION: Considering the scientific data and the large clinical experience with the LM in medical routine and emergency situations in children, currently only the LM can be recommended for alternative (i.e. non-intubation) airway management in children. If alternative airway management is part of a local emergency strategy, the LM should be provided in all pediatric sizes (1, 1.5, 2, 2.5, 3, 4 and 5) for prehospital and in-hospital emergency use and all users should be regularly trained in its application.
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Manuseio das Vias Aéreas/instrumentação , Manuseio das Vias Aéreas/normas , Serviços Médicos de Emergência/normas , Medicina de Emergência/instrumentação , Medicina de Emergência/normas , Máscaras Laríngeas/tendências , Pediatria/instrumentação , Adolescente , Criança , Pré-Escolar , Consenso , Medicina Baseada em Evidências , Humanos , Lactente , Recém-Nascido , Intubação IntratraquealRESUMO
Multigap cavities are used extensively in linear accelerators to achieve velocities up to a few percent of the speed of light, driving nuclear physics research around the world. Unlike for single-gap structures, there is no closed-form expression to calculate the output beam parameters from the cavity voltage and phase. To overcome this, we propose to use a method based on the integration of the first and second moments of the beam distribution through the axially symmetric time-dependent fields of the cavity. A beam-based calibration between the model's electric field scaling and the machine's rf amplitudes is presented, yielding a fast online energy change method, returning cavity amplitude and phase necessary for a desired output beam energy and energy spread. The method is validated with 23Na6+ beam energy measurements.
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The aim of this study was to determine the effect of prolonged 11ß-hydroxysteroid dehydrogenase-1 (11ß-HSD1) inhibition on basal and hormone-stimulated glucose metabolism in fasted conscious dogs. For 7 days prior to study, either an 11ß-HSD1 inhibitor (HSD1-I; n = 6) or placebo (PBO; n = 6) was administered. After the basal period, a 4-h metabolic challenge followed, where glucagon (3×-basal), epinephrine (5×-basal), and insulin (2×-basal) concentrations were increased. Hepatic glucose fluxes did not differ between groups during the basal period. In response to the metabolic challenge, hepatic glucose production was stimulated in PBO, resulting in hyperglycemia such that exogenous glucose was required in HSD-I (P < 0.05) to match the glycemia between groups. Net hepatic glucose output and endogenous glucose production were decreased by 11ß-HSD1 inhibition (P < 0.05) due to a reduction in net hepatic glycogenolysis (P < 0.05), with no effect on gluconeogenic flux compared with PBO. In addition, glucose utilization (P < 0.05) and the suppression of lipolysis were increased (P < 0.05) in HSD-I compared with PBO. These data suggest that inhibition of 11ß-HSD1 may be of therapeutic value in the treatment of diseases characterized by insulin resistance and excessive hepatic glucose production.
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11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Gluconeogênese/fisiologia , Glicogenólise/fisiologia , Hidrocortisona/metabolismo , Fígado/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Cães , Feminino , Glucagon/efeitos dos fármacos , Glucagon/metabolismo , Glucose/metabolismo , MasculinoRESUMO
We present experimental data on a one-dimensional super-conducting metamaterial that is tunable over a broad frequency band. The basic building block of this magnetic thin-film medium is a single-junction (rf-) superconducting quantum interference device (SQUID). Due to the nonlinear inductance of such an element, its resonance frequency is tunable in situ by applying a dc magnetic field. We demonstrate that this results in tunable effective parameters of our metamaterial consisting of 54 rf-SQUIDs. In order to obtain the effective magnetic permeability µr,eff from the measured data, we employ a technique that uses only the complex transmission coefficient S21.
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We have directly imaged the anisotropic nonlinear Meissner effect in an unconventional superconductor through the nonlinear electrodynamic response of both (bulk) gap nodes and (surface) Andreev bound states. A superconducting thin film is patterned into a compact self-resonant spiral structure, excited near resonance in the radio-frequency range, and scanned with a focused laser beam perturbation. At low temperatures, direction-dependent nonlinearities in the reactive and resistive properties of the resonator create photoresponse that maps out the directions of nodes, or of bound states associated with these nodes, on the Fermi surface of the superconductor. The method is demonstrated on the nodal superconductor YBa2Cu3O7-δ and the results are consistent with theoretical predictions for the bulk and surface contributions.
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Interfacing photonic and solid-state qubits within a hybrid quantum architecture offers a promising route towards large scale distributed quantum computing. Ideal candidates for coherent qubit interconversion are optically active spins, magnetically coupled to a superconducting resonator. We report on an on-chip cavity QED experiment with magnetically anisotropic Er(3+)â¶Y2SiO5 crystals and demonstrate collective strong coupling of rare-earth spins to a lumped element resonator. Moreover, the electron spin resonance and relaxation dynamics of the erbium spins are detected via direct microwave absorption, without the aid of a cavity.
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INTRODUCTION: The standard of care for intraperitoneal injury in hemodynamically stable patients after blunt abdominal trauma has been replaced by non-operative management (NOM). However, selective NOM, depending on the situation, seems necessary in determining the treatment plan. In this study, we attempted to identify risk factors for surgical or angiographic intervention (SAI) in hemodynamically stable blunt abdominal trauma patients. METHODS: This retrospective study which included adult patients who were brought to a regional trauma center was conducted from March 2015 to October 2019. We evaluated the characteristics of blunt abdominal trauma patients and analyzed factors that were related to the requirement of SAI in these patients. Patients were divided into SAI and conservative management (CM) groups. RESULTS: We reviewed 1,176 patients, and after exclusions, of whom 248 blunt abdominal trauma and free fluid observed on CT were identified. The mean pulse rate was higher in the SAI than in the CM (P=0.025). Laboratory findings showed that lactate and delta neutrophil index (DNI) levels were higher in the SAI than in the CM (P=0.002 and 0.026 respectively). Additionally, the mean free fluid size in the SAI (85.69mm) was significantly larger than that in the CM (68.12mm; P=0.001), and blush was more frequently observed in the SAI (P<0.001). In multivariate analysis, only blush was an independent prognostic factor for SAI (OR 11.7, 95% CI, 5.1-30.8, P<0.001). CONCLUSION: In hemodynamically stable patients with blunt abdominal trauma, blush but also high lactate and DNI are associated with the requirement of interventional radiology and/or surgery.
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Traumatismos Abdominais , Ferimentos não Penetrantes , Adulto , Humanos , Traumatismos Abdominais/diagnóstico por imagem , Traumatismos Abdominais/cirurgia , Estudos Retrospectivos , Fatores de Risco , Centros de Traumatologia , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/cirurgiaRESUMO
Statistical mechanics demands that the temperature of a system is positive provided that its internal energy has no upper bound. Yet if this condition is not met, it is possible to attain negative temperatures for which higher-order energy states are thermodynamically favored. Although negative temperatures have been reported in spin and Bose-Hubbard settings as well as in quantum fluids, the observation of thermodynamic processes in this regime has thus far remained elusive. Here, we demonstrate isentropic expansion-compression and Joule expansion for negative optical temperatures, enabled by purely nonlinear photon-photon interactions in a thermodynamic microcanonical photonic system. Our photonic approach provides a platform for exploring new all-optical thermal engines and could have ramifications in other bosonic systems beyond optics, such as cold atoms and optomechanics.
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BACKGROUND: Airway management with supraglottic airway devices (SGA) in life-threatening emergencies in children is increasingly being used. Different specifications of laryngeal masks (LM) and the laryngeal tube (LT) are commonly used devices for this purpose. We present a literature review and interdisciplinary consensus statement of different societies on the use of SGA in pediatric emergency medicine. MATERIAL AND METHODS: Literature review in the PubMed database and classification of studies according to the criteria of the Oxford Centre for Evidence-based Medicine. Levels and consensus finding within the group of authors. RESULTS: The evidence for successful applications of the various types of LM is significantly higher than for LT application. Reported smaller series of successful applications of LT are currently limited to selected research groups and centers. Especially for children below 10â¯kg body weight there currently exists insufficient evidence for the successful application of the LT and therefore its routine use cannot be recommended. SGAs used for emergencies should have a gastric drainage possibility. DISCUSSION: Considering the scientific data and the large clinical experience with the LM in medical routine and emergency situations in children currently only the LM can be recommended for alternative (i.e., non-intubation) emergency airway management in children. If alternative airway management is part of a local emergency strategy, the LM should be provided in all pediatric sizes (1, 1½, 2, 2½, 3) for out of hospital use and in hospital emergency use and all users should regularly be trained in its application.
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Anestesia , Anestesiologia , Serviços Médicos de Emergência , Medicina de Emergência , Máscaras Laríngeas , Neonatologia , Medicina de Emergência Pediátrica , Diretores Médicos , Criança , Humanos , Intubação Intratraqueal , Emergências , Universidades , Manuseio das Vias Aéreas , Cuidados Críticos , AlemanhaRESUMO
Light-sheet microscopy enables considerable speed and phototoxicity gains, while quantitative-phase imaging confers label-free recognition of cells and organelles, and quantifies their number-density that, thermodynamically, is more representative of metabolism than size. Here, we report the fusion of these two imaging modalities onto a standard inverted microscope that retains compatibility with microfluidics and open-source software for image acquisition and processing. An accelerating Airy-beam light-sheet critically enabled imaging areas that were greater by more than one order of magnitude than a Gaussian beam illumination and matched exactly those of quantitative-phase imaging. Using this integrative imaging system, we performed a demonstrative multivariate investigation of live-cells in microfluidics that unmasked that cellular noise can affect the compartmental localization of metabolic reactions. We detail the design, assembly, and performance of the integrative imaging system, and discuss potential applications in biotechnology and evolutionary biology.
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Neurofilaments are transported along axons in the slow component of axonal transport. The average rate of movement is generally quoted as several millimeters or tenths of a millimeter per day, but this rate is known to decrease while the neurofilaments are in transit due to spatial and temporal factors that are not understood. We have previously presented a stochastic model for neurofilament movement in vivo based on the transport kinetics of single neurofilaments observed by time-lapse fluorescence imaging in cultured neurons. The model took into account multiple velocity states and was only accessible through computational simulations. In simulations of the movement of a pulse of radiolabeled neurofilaments, this model generated a Gaussian wave which closely matched the experimental data. Here we present a simpler model with only three velocity states which is more amenable to analytical approaches. We show that the transport wave can be fully described by the mean and variance and we present analytical solutions for these cumulants in terms of the kinetic parameters of the model. We use the resulting expressions to examine the slowing of neurofilament transport in the mouse sciatic nerve. We show that the slowing is accompanied by an increase in the spread of the wave and that these changes are most readily explained by a change in the rate at which neurofilaments reverse their direction of movement. This suggests that the directionality of neurofilament transport in axons may be under spatial and/or temporal control and that alterations in the directionality of neurofilament transport could provide a mechanism for regulating the transport and distribution of these cytoskeletal polymers along axons.
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Filamentos Intermediários/metabolismo , Modelos Neurológicos , Nervo Isquiático , Animais , Transporte Biológico , Células Cultivadas , Camundongos , Nervo Isquiático/metabolismo , Fatores de TempoRESUMO
The gradual closure of the Panamanian seaway and the resulting environmental change stimulated an increase in Caribbean molluscan diversity rather than the mass extinction hypothesized previously on the basis of inadequate data. Upheaval of molluscan faunas did occur suddenly throughout tropical America at the end of the Pliocene as a result of more subtle, unknown causes. There is no necessary correlation between the magnitude of regional shifts in abiotic conditions and the subsequent biological response.
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The aim of this article was to report the emergence of patient infections with linezolid-resistant Staphylococcus epidermidis (LRSE) in a tertiary university hospital. Our objectives were to determine the molecular mechanism of the resistance, set up the genetic relationship among isolates, and analyze the relations between linezolid usage, period of treatment, and emergence of resistance in the hospital. The emergence of infection with linezolid-resistant S. epidermidis affecting 20 patients in a tertiary university hospital was investigated using repetitive sequence-based PCR (rep-PCR, DiversiLab System; BioMérieux, Inc., France). The presence of the G2576T mutation of 23S rRNA was screened by pyrosequencing. We determined the pattern of linezolid usage in the hospital as a whole and in the critical care unit that was most affected. G2576T mutation of 23S rRNA was detected in all linezolid-resistant S. epidermidis studied. Of these, 90% were genetically related and had been recovered from patients admitted to the same critical care unit. There had been an increase in linezolid usage in the hospital and in the critical care unit in the 2 years prior to the emergence of resistant strains. More strict control measures in hand washing and linezolid prescription were subsequently established, but no reduction in LRSE rates have yet been observed. Linezolid-resistant S. epidermidis emerged at our hospital, probably from a single strain originating in the critical care unit. The most likely explanation is that person-to-person spread of linezolid-resistant S. epidermidis led to skin colonization and, after linezolid treatment, this resistant staphylococci became the dominant cutaneous flora causing infection in some critical patients. In order to preserve the usefulness of this antibiotic as a therapeutic agent and to avoid a situation similar to methicillin-resistant Staphylococcus aureus, judicious use of antibiotics is essential.