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1.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38456758

RESUMEN

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.

2.
[Update 2022: interdisciplinary statement on airway management with supraglottic airway devices in pediatric emergency medicine-The laryngeal mask is and remains state of the art : Joint statement of the Institute for Emergency Medicine and Medicine Management (INM), the University Clinic Munich, LMU Munich, Germany, the Working Group for Pediatric Critical Care and Emergency Medicine of the German Interdisciplinary Society for Critical Care and Emergency Medicine (DIVI), the Medical Directors of Emergency Medical Services in Bavaria (ÄLRD), the Scientific Working Group for Pediatric Anesthesia (WAKKA) of the German Society for Anesthesiology and Intensive Care Medicine (DGAI), the Scientific Working Group for Emergency Medicine of the German Society for Anesthesiology and Intensive Care Medicine (DGAI) and the Society of Neonatology and Pediatric Critical Care Medicine (GNPI)]. / Update 2022: Interdisziplinäre Stellungnahme zum Atemwegsmanagement mit supraglottischen Atemwegshilfen in der Kindernotfallmedizin ­ die Larynxmaske ist und bleibt State of the Art : Gemeinsame Stellungnahme des Instituts für Notfallmedizin und Medizinmanagement (INM), Klinikum der Universität München, der Sektion Pädiatrische Intensiv- und Notfallmedizin der Deutschen Interdisziplinären Vereinigung für Intensiv- und Notfallmedizin (DIVI), des Ärztlicher Leiter Rettungsdienst Bayern (ÄLRD Bayern), des Wissenschaftlichen Arbeitskreises Kinderanästhesie (WAKKA) der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin (DGAI), des Wissenschaftlichen Arbeitskreises Notfallmedizin der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin (DGAI) und der Gesellschaft für Neonatologie und Pädiatrische Intensivmedizin (GNPI).
Anaesthesiologie ; 72(6): 425-432, 2023 06.
Artículo en Alemán | MEDLINE | ID: mdl-37222766

RESUMEN

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 10 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.


Asunto(s)
Anestesia , Anestesiología , Servicios Médicos de Urgencia , Medicina de Emergencia , Máscaras Laríngeas , Neonatología , Medicina de Urgencia Pediátrica , Ejecutivos Médicos , Niño , Humanos , Intubación Intratraqueal , Urgencias Médicas , Universidades , Manejo de la Vía Aérea , Cuidados Críticos , Alemania
3.
Science ; 379(6636): 1019-1023, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36893226

RESUMEN

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.

4.
J Visc Surg ; 160(1): 12-18, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35459632

RESUMEN

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.


Asunto(s)
Traumatismos Abdominales , Heridas no Penetrantes , Adulto , Humanos , Traumatismos Abdominales/diagnóstico por imagen , Traumatismos Abdominales/cirugía , Estudios Retrospectivos , Factores de Riesgo , Centros Traumatológicos , Heridas no Penetrantes/diagnóstico por imagen , Heridas no Penetrantes/cirugía
6.
Opt Express ; 29(20): 31941-31951, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34615275

RESUMEN

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.


Asunto(s)
Aumento de la Imagen/métodos , Iluminación/métodos , Microscopía/métodos , Espectrometría Raman/métodos , Dimetilpolisiloxanos , Microscopía Fluorescente/métodos
7.
Sci Rep ; 10(1): 20150, 2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-33214600

RESUMEN

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.

9.
Phys Biol ; 17(4): 046004, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32369788

RESUMEN

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.


Asunto(s)
Dineínas Citoplasmáticas/metabolismo , Adenosina Trifosfato/metabolismo , Cinética , Modelos Biológicos
10.
MMW Fortschr Med ; 161(16): 36, 2019 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-31556038
13.
Medicine (Baltimore) ; 96(19): e6666, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28489742

RESUMEN

Cardiovascular disease (CVD) is the main public health problem in patients with chronic kidney disease (CKD); however, there is no established biomarker for predicting CVD morbidity and mortality in CKD. The aim of this study was to evaluate the role of circulating tumor necrosis factor receptors (cTNFRs) in predicting CVD risk in CKD patients.We prospectively recruited 984 patients with CKD from 11 centers between 2006 and 2012. The levels of cTNFR1 and cTNFR2 were determined by performing an enzyme-linked immunosorbent assay. During the mean follow-up period of 4 years, 36 patients experienced a CVD event. The median serum concentrations of cTNFR1 and cTNFR2 were 2703.4 (225.6-13,057.7) and 5661.0 (634.9-30,599.6) pg/mL, respectively, and the cTNFR1 level was closely correlated with the cTNFR2 level (r = 0.86, P < .0001). The urinary protein-to-creatinine ratio (UPCR) and estimated glomerular filtration rate (eGFR) were significantly correlated with the cTNFR2 level (r = 0.21 for UPCR, r = -0.67 for eGFR; P < .001 for all). Similar correlations were observed for serum cTNFR1 (r = 0.21 for UPCR, r = -0.75 for eGFR; P < .001 for all). In the Cox proportional hazard analyses, cTNFR1 (hazard ratio [HR] 2.506, 95% confidence interval [CI] 1.186-5.295, P = .016) and cTNFR2 (HR 4.156, 95% CI 1.913-9.030, P < .001) predicted CVD risk even after adjustment for clinical covariates, such as UPCR, eGFR, and high-sensitivity C-reactive protein. cTNFR1 and 2 are associated with CVD and other risk factors in CKD, independently of eGFR and UPCR. Furthermore, cTNFRs could be relevant predictors of CVD in CKD patients.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/complicaciones , Receptores Tipo II del Factor de Necrosis Tumoral/sangre , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Adulto , Anciano , Análisis Químico de la Sangre , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/orina , Creatinina/orina , Porocarcinoma Ecrino , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/orina , Factores de Riesgo
14.
Anaesthesist ; 66(5): 340-346, 2017 May.
Artículo en Alemán | MEDLINE | ID: mdl-28455650

RESUMEN

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.


Asunto(s)
Recursos Audiovisuales/estadística & datos numéricos , Servicios Médicos de Urgencia/métodos , Pediatría/métodos , Adolescente , Estatura , Peso Corporal , Niño , Preescolar , Consenso , Humanos , Lactante , Recién Nacido , Errores de Medicación/prevención & control , Preparaciones Farmacéuticas/administración & dosificación
16.
Mucosal Immunol ; 9(4): 950-9, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26530134

RESUMEN

Ulcerative colitis (UC) is a chronic intestinal inflammatory disease that may undergo periods of activity followed by remission. We aimed to identify the endogenous regulatory mechanisms that may promote disease remission. Transcriptional and protein analysis of the intestinal mucosa revealed that the IL-1 decoy receptor, interleukin-1 receptor type 2 (IL1R2), was upregulated in remission compared with active UC and controls. We identified epithelial cells as being responsible for increased IL-1R2 production during remission. Expression of IL1R2 was negatively regulated by Wnt/beta-catenin signals in colonic crypts or epithelial stem cell cultures; accordingly, epithelial stem cells upregulated IL-1R2 upon differentiation. Blocking IL-1R2 in isolated colonic crypt cultures of UC patients in remission and T-cell cultures stimulated with biopsy supernatant from UC patients in remission boosted IL-1ß-dependent production of inflammation-related cytokines. Finally, IL1R2 transcription was significantly lower in patients that relapsed during a 1-year follow-up period compared with those in endoscopic remission. Collectively, our results reveal that the IL-1/IL-1R2 axis is differentially regulated in the remitting intestinal mucosa of UC patients. We hypothesize that IL-1R2 in the presence of low concentrations of IL-1ß may act locally as a regulator of intestinal homeostasis.


Asunto(s)
Colitis Ulcerosa/inmunología , Mucosa Intestinal/inmunología , Receptores Tipo II de Interleucina-1/metabolismo , Linfocitos T/inmunología , Adulto , Anciano , Células Cultivadas , Femenino , Estudios de Seguimiento , Homeostasis , Humanos , Interleucina-1beta/metabolismo , Masculino , Persona de Mediana Edad , Receptores Tipo II de Interleucina-1/genética , Remisión Espontánea , Transducción de Señal , Regulación hacia Arriba , Proteínas Wnt/metabolismo , Adulto Joven , beta Catenina/metabolismo
17.
Anaesthesist ; 65(1): 57-66, 2016 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-26661389

RESUMEN

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.


Asunto(s)
Manejo de la Vía Aérea/instrumentación , Manejo de la Vía Aérea/normas , Servicios Médicos de Urgencia/normas , Medicina de Emergencia/instrumentación , Medicina de Emergencia/normas , Máscaras Laríngeas/tendencias , Pediatría/instrumentación , Adolescente , Niño , Preescolar , Consenso , Medicina Basada en la Evidencia , Humanos , Lactante , Recién Nacido , Intubación Intratraqueal
18.
J Vestib Res ; 24(4): 281-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25095772

RESUMEN

BACKGROUND: Seasickness is a risk aboard a ship. Histamine is postulated as a causative agent, inversely related to the intake of vitamin C. Persons with mastocytosis experienced improvement of nausea after the intake of vitamin C. OBJECTIVE: To determine whether vitamin C suppresses nausea in 70 volunteers who spent 20 minutes in a life raft, exposed to one-meter-high waves in an indoor pool. METHOD: Double-blind placebo-controlled crossover study. Two grams of vitamin C or placebo was taken one hour before exposure. Blood samples were taken one hour before and after exposure to determine histamine, diamine oxidase, tryptase, and vitamin C levels. Symptom scores were noted on a visual analog scale. On the second day the test persons were asked which day they had felt better. RESULTS: Seven persons without symptoms were excluded from the analysis. Test persons had less severe symptoms after the intake of vitamin C (p < 0.01). Scores on the visual analog scale were in favor of vitamin C, but the difference was not significant. Twenty-three of 63 persons wished to leave the raft earlier: 17 after the intake of placebo and 6 after the intake of vitamin C (p < 0.03). Women (p < 0.02) and men below 27 years of age (p < 0.02) had less pronounced symptoms after the intake of vitamin C. Histamine (p < 0.01) and DAO levels were increased after the intake of vitamin C (p < 0.001) and after placebo (n.s.). The fact that the second test day was rated less stressful by most volunteers is indicative of habituation. CONCLUSIONS: Some of the data show that vitamin C is effective in suppressing symptoms of seasickness, particularly in women and men younger than 27 years of age, and is devoid of side effects. Histamine levels were initially increased after the test persons had been exposed to waves.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Histamina/sangre , Mareo por Movimiento/sangre , Mareo por Movimiento/tratamiento farmacológico , Administración Oral , Adulto , Factores de Edad , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placebos , Factores Sexuales , Adulto Joven
20.
Nat Commun ; 5: 3730, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24769498

RESUMEN

The field of metamaterial research revolves around the idea of creating artificial media that interact with light in a way unknown from naturally occurring materials. This is commonly achieved using sub-wavelength lattices of electronic or plasmonic structures, so-called meta-atoms. One of the ultimate goals for these tailored media is the ability to control their properties in situ. Here we show that superconducting quantum interference devices can be used as fast, switchable meta-atoms. We find that their intrinsic nonlinearity leads to simultaneously stable dynamic states, each of which is associated with a different value and sign of the magnetic susceptibility in the microwave domain. Moreover, we demonstrate that it is possible to switch between these states by applying nanosecond-long pulses in addition to the microwave-probe signal. Apart from potential applications for this all-optical metamaterial switch, the results suggest that multistability can also be utilized in other types of nonlinear meta-atoms.


Asunto(s)
Conductividad Eléctrica , Modelos Químicos , Nanoestructuras , Microondas , Teoría Cuántica
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