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1.
Nat Commun ; 15(1): 1068, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316779

RESUMEN

Combining superconducting resonators and quantum dots has triggered tremendous progress in quantum information, however, attempts at coupling a resonator to even charge parity spin qubits have resulted only in weak spin-photon coupling. Here, we integrate a zincblende InAs nanowire double quantum dot with strong spin-orbit interaction in a magnetic-field resilient, high-quality resonator. The quantum confinement in the nanowire is achieved using deterministically grown wurtzite tunnel barriers. Our experiments on even charge parity states and at large magnetic fields, allow us to identify the relevant spin states and to measure the spin decoherence rates and spin-photon coupling strengths. We find an anti-crossing between the resonator mode in the single photon limit and a singlet-triplet qubit with a spin-photon coupling strength of g/2π = 139 ± 4 MHz. This coherent coupling exceeds the resonator decay rate κ/2π = 19.8 ± 0.2 MHz and the qubit dephasing rate γ/2π = 116 ± 7 MHz, putting our system in the strong coupling regime.

2.
Clin Nutr ; 40(4): 1571-1577, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33744601

RESUMEN

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (alloHSCT) is frequently associated with impaired oral intake and malnutrition, which potentially increases morbidity and mortality. Therefore, nutrition is one of the major challenges in the post-transplant period. METHODS: To document the current clinical approach in nutritional treatment, we designed a questionnaire concerning the current practice in nutrition after alloHSCT and distributed it to German speaking centers performing alloHSCT in Germany, Austria and Switzerland between November 2018 and March 2020. Twenty-eight (39%) of 72 contacted centers completed the survey, 23 from Germany, two from Austria and three from Switzerland, representing 50% of alloHSCT activity within the participating countries in 2018. RESULTS: All centers reported having nutritional guidelines for patients undergoing alloHSCT, whereby 86% (n = 24) provided a low-microbial diet during the neutropenic phase. The criteria to start parenteral nutrition (PN) directly after alloHSCT seemed to be consistent, 75% (n = 21) of the corresponding centers started PN if the oral nutritional intake or the bodyweight dropped below a certain limit. In the setting of intestinal graft-versus-host disease (GvHD) the current practice appeared to be more heterogenous. About 64% (n = 18) of the centers followed a special diet, added food stepwise modulated by GvHD symptoms, while only four centers regularly stopped oral intake completely (intestinal GvHD grade >1). Half of the centers (54%, n = 15) applied a lactose-free diet, followed by 43% (n = 12) which provided fat- and 18% (n = 5) gluten-free food in patients with intestinal GvHD. Supplementation of micronutrients in acute intestinal GvHD patients was performed by 54% (n = 15) of the centers, whereas vitamin D (89%, n = 25) and vitamin B12 (68%, n = 19) was added regularly independently of the presence of GvHD. Only 5 (18%) participating centers ever observed a food-associated infection during hospitalization, whereas food-associated infections were reported to occur more often in the outpatient setting (64%, n = 18). CONCLUSION: The survey documented a general consensus about the need for nutritional guidelines for patients undergoing alloHSCT. However, the nutritional treatment in clinical practice (i.e. lactose-, gluten- or fat-free in intestinal GvHD) as well as the use of food supplements was very heterogeneous. In line with current general recommendations the centers seemed to focus on safe food handling practice rather than providing a strict neutropenic diet. More high-quality data are required to provide evidence-based nutrition to patients during and after alloHSCT.


Asunto(s)
Dieta/métodos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Desnutrición/prevención & control , Neutropenia/dietoterapia , Política Nutricional , Austria , Peso Corporal , Consenso , Dieta/normas , Suplementos Dietéticos , Ingestión de Alimentos , Alemania , Encuestas de Atención de la Salud , Humanos , Desnutrición/etiología , Neutropenia/etiología , Nutrición Parenteral/normas , Pautas de la Práctica en Medicina , Suiza
3.
Theriogenology ; 151: 7-15, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32251939

RESUMEN

The objective of this study was to evaluate the local effect of the corpus luteum (CL) on ipsilateral oviduct-uterus functionality and early embryo development in ewes. A total of 499 embryos were transferred on Day 1 after in vitro fertilization into the ipsilateral (n = 250) and contralateral oviducts (n = 249) of 13 ewes on Day 1 after ovulation (18-20 embryos per oviduct). On Day 6, their reproductive tracts were collected and their uterine horns were flushed for embryo recovery. More recovered embryos, a higher proportion of blastocysts, and more viable embryos were collected when the embryos were transferred into the ipsilateral oviducts (P < 0.05). In addition, almost five times higher P4 concentrations and significantly lower E2 concentrations, with higher P4:E2 ratio, were found in the ipsilateral than contralateral oviductal tissue (P < 0.05). Furthermore, a higher concentration of adiponectin was found in the ipsilateral uterine tissue macerates than in the contralateral side to the CL. The ipsilateral oviductal tissue had a lower expression of PGR and IGFBP5, but the transcript expression of ADIPOR1 was higher in the ipsilateral oviductal tissue. In the uterus, the mRNA expression of ESR1, IGFBP3, IGFBP5, and LEPR was higher or tended to be higher in the ipsilateral than contralateral uterine tissue. Uterine flushing fluid collected from the ipsilateral uterine horn had lower insulin concentrations than the contralateral horn, while no differences were found in the P4 and E2 concentrations. In conclusion, on Day 6 post-ovulation, P4 was elevated in the ipsilateral oviductal tissue, embryo development was advanced, and differential gene expression of PGR, ESR1, IGFBP3, IGFBP5, LEPR, and ADIPOR1 in the oviductal or uterine tissue was found between the ipsilateral and contralateral side. This study demonstrates local regulation of the ovary on the ipsilateral oviduct/uterine horn in the ewe.


Asunto(s)
Cuerpo Lúteo/fisiología , Embrión de Mamíferos , Desarrollo Embrionario , Trompas Uterinas/fisiología , Ovinos/fisiología , Animales , Femenino
4.
Phys Rev Lett ; 123(23): 233601, 2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31868492

RESUMEN

We investigate a Bose-Einstein condensate strongly coupled to an optical cavity via a repulsive optical lattice. We detect a stable self-ordered phase in this regime, and show that the atoms order through an antisymmetric coupling to the P band of the lattice, limiting the extent of the phase and changing the geometry of the emergent density modulation. Furthermore, we find a nonequilibrium phase with repeated intense bursts of the intracavity photon number, indicating nontrivial driven-dissipative dynamics.

5.
Toxicol Lett ; 310: 1-6, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30980909

RESUMEN

The increased number of cell divisions undergone by spermatogonia of older fathers cannot fully account for the observed increase in germline genetic damage. Studies have shown that the mechanisms induced in germ cells in response to oxidative damage varies with age, that DNA repair efficiency declines, and both sperm DNA damage and spontaneous mutations increase. However, it is not known whether the altered response with age is a cause, or consequence, of an age-associated change in cell susceptibility to genetic damage. Following a single 150 mg/kg dose of cyclophosphamide (CP), young (8-weeks old) and aged (17-month old) male mice were examined 24 h later for induced genetic damage in epididymal spermatozoa using the alkaline comet and sperm chromatin stability assays. Apoptosis among testicular cells was examined on tissue cross-sections using the TUNEL assay. Sperm showed no significant increase in DNA strand breaks with age (detected by the comet assay) and no change in sperm chromatin stability (detected by the SCSA assay). Following CP treatment, there was no effect on DNA-strand breakage but sperm chromatin instability was significantly higher. Furthermore, it was also significantly elevated in old treated, compared with young treated, animals suggesting that increased age affects the sensitivity of epididymal sperm to chromatin damage. There was no difference in apoptosis in testicular germ cells from either young or old control animals, while CP administration resulted in a significant increase in apoptosis among young animals but not old animals. Following genotoxin exposure, an increase in chromatin instability in the spermatozoa of old animals and a decrease in the ability of their testicular germ cells undergo apoptosis suggests an age-related decrease in genome protection mechanisms. Since those germ cells are only transiently present in the testis, it is likely that this age-related deterioration originates in the spermatogonial stem cells. The findings are also evidence that the safety evaluation of reproductive genotoxins should consider young and old individuals separately.


Asunto(s)
Ciclofosfamida/toxicidad , Epidídimo/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Factores de Edad , Animales , Apoptosis/efectos de los fármacos , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Ensayo Cometa , Daño del ADN , Epidídimo/metabolismo , Epidídimo/patología , Etiquetado Corte-Fin in Situ , Masculino , Ratones Endogámicos C3H , Medición de Riesgo , Espermatozoides/metabolismo , Espermatozoides/patología , Testículo/metabolismo , Testículo/patología
6.
New Microbes New Infect ; 27: 22-26, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30534383

RESUMEN

Ticks are vectors of several microorganisms responsible for infectious diseases in human and animals, such as Anaplasma phagocytophilum and Coxiella burnetii. In this study, we investigated the prevalence of these two bacteria in 62 889 Ixodes ricinus ticks in selected regions covering all Switzerland. A high prevalence of 11.9% of A. phagocytophilum DNA was observed by real-time PCR on 8534 pools of ticks. This pool prevalence corresponds to an estimated prevalence of 1.71% in individual tick. A total of 144 of the 171 collection sites (84.2%) were positive for the presence of A. phagocytophilum, and these sites were homogenously distributed throughout Switzerland. Such prevalence and geographical distribution underline the risk of human and animal exposure to A. phagocytophilum and highlight the need to assess the epidemiology and clinical diagnosis of human and animal anaplasmosis in Switzerland. However, DNA of C. burnetii was never found in any tick pool. This absence suggests a very low role of I. ricinus ticks as vector and reservoir of C. burnetii in Switzerland, and it supports previous reports demonstrating the role of sheep and goats in the epidemiology of Q fever. However, considering its pathogenic potential, it is necessary to keep monitoring for the possible reemergence of this bacterium in ticks in the future.

7.
Fluids Barriers CNS ; 15(1): 31, 2018 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-30392467

RESUMEN

BACKGROUND: Cerebrospinal fluid (CSF) analysis is a crucial method in the diagnostic process for suspected subarachnoid hemorrhage (SAH), especially when cerebral imaging is negative or inconclusive. CSF cytology (detection of erythrophages or siderophages) is used to determine whether a bloodstained CSF resembles a genuine SAH. Whether erythrophages may develop in vitro after a traumatic puncture in case of delayed CSF analysis is unclear. An in vitro development of erythrophages after traumatic puncture would diminish the diagnostic properties of CSF analysis. We assessed whether erythrophagocytosis is detectable in CSF after an imitated traumatic lumbar puncture. METHODS: We mimicked a traumatic lumbar puncture by mixing surplus CSF with whole blood from the same patient. From this mixture, cytological specimens were obtained immediately and repeatedly at time intervals of 1 h, until 7 h after mixing, or until the mixture was exhausted. Each cytological specimen was microscopically examined independently by four experienced CSF cytologists for the presence of erythrophages. RESULTS: We studied 401 CSF cytological specimens of 96 punctures in 90 patients. We could not identify any erythrophages in all cytological specimens. Fleiss' Kappa for interrater-reliability was 1.0. CONCLUSIONS: We did not find evidence for an in vitro erythrophagocytosis after a mimicked traumatic lumbar puncture. Therefore, the occurrence of erythrophages in CSF cytology can be regarded as a reliable sign of an autochthonous bleeding in the subarachnoid space. Our results support the crucial role of CSF analysis in clinical practice in case of a suspected SAH but negative cerebral imaging.


Asunto(s)
Líquido Cefalorraquídeo/citología , Médula Espinal/citología , Hemorragia Subaracnoidea/sangre , Hemorragia Subaracnoidea/líquido cefalorraquídeo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Punción Espinal
8.
J Appl Microbiol ; 125(4): 1216-1225, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29802665

RESUMEN

AIMS: A molecular method for a rapid detection of viable Legionella pneumophila of all serogroups in tap water samples was developed as an alternative to the reference method (ISO). Legionellae are responsible for Legionnaires' disease, a severe pneumonia in humans with high lethality. METHODS AND RESULTS: The developed method is based on a nutritional stimulation and detection of an increase in precursor 16S rRNA as an indicator for viability. For quantification, DNA was detected by qPCR. This method was compared to the ISO method using water samples obtained from public sports facilities in Switzerland. The sensitivity and specificity were 91 and 97%, respectively, when testing samples for compliance with a microbiological criterion of 1000 cell equivalents per l. CONCLUSION: The new method is sensitive and specific for Leg. pneumophila and allows results to be obtained within 8 h upon arrival, compared to one week or more by the ISO method. SIGNIFICANCE AND IMPACT OF THE STUDY: The method represents a useful tool for a rapid detection of viable Leg. pneumophila of all serogroups in water by molecular biology. It can be used as an alternative to the ISO method for official water analysis for legionellae and particularly when a short test time is required.


Asunto(s)
Agua Dulce/microbiología , Legionella pneumophila/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , ADN Bacteriano/genética , Humanos , Legionella pneumophila/clasificación , Legionella pneumophila/genética , Legionella pneumophila/crecimiento & desarrollo , Enfermedad de los Legionarios/microbiología , Viabilidad Microbiana , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad , Microbiología del Agua
9.
J Intern Med ; 284(3): 270-281, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29664160

RESUMEN

BACKGROUND: Hyponatremia is a common feature of acute illness and associated with increased mortality. This may be explained by a stress-mediated activation of the vasopressin system with an increase in free-water reabsorption. OBJECTIVES: To investigate whether the association between hyponatremia and mortality could be explained by activation of the vasopressin system. METHODS: We prospectively enrolled adult, medical patients seeking emergency care in three centres in Switzerland, France and the United States. We investigated associations between admission plasma sodium and copeptin, a stable portion of the vasopressin-precursor peptide, with 30-day mortality. We performed uni- and multivariate regression analysis. RESULTS: Of 6962 included patients, 18% had hyponatremia (sodium ≤135 mmol L-1 ), which doubled their risk for mortality compared to patients with normonatremia (8.3% vs. 3.8%). This association was confirmed in a multivariate-adjusted logistic regression analysis [adjusted odds ratio (OR) 1.47, 95% CI 1.12-1.93, P = 0.005]. Vasopressin levels, mirrored by copeptin, were also increased in nonsurvivors and strongly associated with mortality (adjusted OR 3.42, 95% CI 2.76-4.25, P < 0.001). The association between hyponatremia and mortality remained unchanged when adding copeptin levels to the regression model (fully adjusted OR 1.53, 95% CI 1.16-2.00, P = 0.002). CONCLUSION: This prospective study including medical patients upon emergency room admission found hyponatremia as well as an activation of the vasopressin system to be independently associated with mortality. This suggests that stress- and vasopressin-independent mechanisms are responsible for the association of low sodium levels with mortality.


Asunto(s)
Enfermedad Aguda/mortalidad , Hiponatremia/sangre , Hiponatremia/mortalidad , Vasopresinas/sangre , Adulto , Anciano , Estudios de Cohortes , Correlación de Datos , Comparación Transcultural , Servicio de Urgencia en Hospital , Femenino , Francia , Glicopéptidos/sangre , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Riesgo , Tasa de Secreción/fisiología , Sodio/sangre , Suiza , Estados Unidos
10.
J Water Health ; 16(1): 138-149, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29424727

RESUMEN

Water resources situated in areas with underlying karst geology are particularly vulnerable to fecal pollution. In such vulnerable systems, microbial source tracking (MST) methods are useful tools to elucidate the pathways of both animal and human fecal pollution, leading to more accurate water use risk assessments. Here, we describe the application of a MST toolbox using both culture-dependent bacteriophage and molecular-dependent 16S rRNA assays at spring and well sites in the karstic St Imier Valley, Switzerland. Culture-dependent and molecular-dependent marker performance varied significantly, with the 16S rRNA assays displaying greater sensitivity than their phage counterpart; HF183 was the best performing human wastewater-associated marker while Rum2Bac was the best performing ruminant marker. Differences were observed in pollution regimes between the well and spring sampling sites, with the spring water being more degraded than the well site. Our results inform the choice of marker selection for MST studies and highlight differences in microbial water quality between well and spring karst sites.


Asunto(s)
Agua Potable/microbiología , Monitoreo del Ambiente/métodos , Microbiología del Agua , Recursos Hídricos , Animales , Bacteriófagos/aislamiento & purificación , Humanos , Reacción en Cadena de la Polimerasa , Medición de Riesgo , Suiza , Virus/aislamiento & purificación , Calidad del Agua
11.
Rev Sci Instrum ; 89(12): 123106, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30599544

RESUMEN

While most experiments on water or ice utilize rather complex, elaborate, and expensive apparatus in order to obtain reliable optical data, here we present a simple and affordable setup that enables us to perform near-infrared measurements on water, ice, and snow on top of rough diffuse reflecting surfaces such as concrete, stone, pavement, or asphalt. By using the properties of diffuse scattering instead of specular reflection, we are able to determine the imaginary part of the refraction index of water without using any liquid cells. In addition, we demonstrate that the snow spectra can be well described by newly developed two-dimensional ray tracing simulations.

12.
Appl Radiat Isot ; 134: 45-50, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29079417

RESUMEN

This paper outlines the process of characterizing a new NORM material for proficiency testing made of quartz sand with significantly elevated levels of 226Ra obtained from the backflush of a drinking water treatment facility. Samples of the fully characterized NORM material were sent to European laboratories concerned with radioactivity measurements and environmental monitoring by gamma-ray spectrometry for proficiency testing. The paper discusses the results, specific requirements, problems and solutions that were found during the characterization process and the proficiency test.

13.
Radiat Prot Dosimetry ; 177(1-2): 213-219, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28981810

RESUMEN

The European Basic Safety Standards demand the prediction of areas where a significant number of households exceed the reference level for the radon activity concentration. Therefore, radon maps are established which are based on indoor and soil gas measurements. In this study results of soil gas measurements are interpolated to get a value for the radon activity concentration in the soil gas at the coordinates of an indoor measurement and enable a direct comparison of both results. For the interpolation the inverse weighting value is applied. This way a prediction of the indoor radon activity concentration at the location of indoor measurements is attempted for verification. Quotients between the radon activity concentration in soil gas and indoors are analyzed. Building characteristics are also taken into account to evaluate parameters which lead to the reference level being exceeded. The results assist in the interpretation of soil gas measurements regarding the prediction of indoor radon activity concentrations.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Monitoreo de Radiación/métodos , Radón/análisis , Contaminantes Radiactivos del Suelo/análisis , Austria , Valor Predictivo de las Pruebas
14.
Radiat Prot Dosimetry ; 177(1-2): 26-30, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29036707

RESUMEN

The radioactive noble gas radon is identified as the highest risk factor for lung cancer after smoking. The exhalation of radon from building materials can contribute to the radon indoor activity concentration. Therefore, the emanation of radon might be a crucial factor. It is defined as the release of radon from the solid soil matter into the pore space of the material. This article describes a new on-site measurement method for the emanation of radon from building materials at industrial sites. Therefore, a closed vessel with sample material and a passive radon detector inside is used to measure the integrated build-up-curve of the activity concentration. Additionally, a brief overview on existing radon emanation measurement methods is given.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Materiales de Construcción , Monitoreo de Radiación/métodos , Radón/análisis
16.
Bone Marrow Transplant ; 52(4): 506-513, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28067888

RESUMEN

In 2009, the American Society of Parenteral and Enteral Nutrition and its European counterpart (Euopean Society for Parenteral and Enteral Nutrition) published guidelines regarding nutritional support of patients with hematologic stem cell transplantation. Our aim was to do an up-to-date literature review regarding benefit of nutritional interventions and treatment recommendations. We searched MEDLINE, EMBASE and Cochrane Library for interventional and observational clinical studies. We extracted data based on a predefined case report form and assessed bias. Out of 459 potential abstracts, 13 studies of mostly moderate quality with a total of 18 167 patients were included. Two very large trials reported negative associations of malnutrition and survival, transplant-related mortality and relapse risk. Some trials found enteral nutrition (EN) to be as effective as parenteral nutrition (PN) with lower complication rates. In addition, EN was associated with better survival, less acute GvHD and faster neutrophil recovery. A neutropenic diet was not superior regarding overall survival, but in contrast resulted in higher infection risk. Current moderate quality studies show negative associations of malnutrition and clinical outcomes, with EN being superior to PN. There was no benefit of neutropenic diets. Large, randomized controlled studies are needed to better understand optimal nutritional support in this patient population.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Apoyo Nutricional/normas , Nutrición Enteral/normas , Humanos , Desnutrición , Apoyo Nutricional/métodos , Nutrición Parenteral/normas , Resultado del Tratamiento
17.
J Environ Radioact ; 173: 6-10, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27554706

RESUMEN

The administration in many countries demands a classification of areas concerning their radon risk taking into account the requirements of the EU Basic Safety Standards. The wide variation of indoor radon concentrations in an area which is caused by different house construction, different living style and different geological situations introduces large uncertainties for any classification scheme. Therefore, it is of importance to estimate the size of the experimental coefficient of variation (relative standard deviation) of the parameter which is used to classify an area. Besides the time period of measurement it is the number of measurements which strongly influences this uncertainty and it is important to find a compromise between the economic possibilities and the needed confidence level. Some countries do not use pure measurement results for the classification of areas but use derived quantities, usually called radon potential, which should reduce the influence of house construction, living style etc. and should rather represent the geological situation of an area. Here, radon indoor measurements in nearly all homes in three municipalities and its conversion into a radon potential were used to determine the uncertainty of the mean radon potential of an area as a function of the number of investigated homes. It could be shown that the coefficient of variation scales like 1/√n with n the number of measured dwellings. The question how to deal with uncertainties when using a classification scheme for the radon risk is discussed and a general procedure is proposed.


Asunto(s)
Contaminantes Radiactivos del Aire/normas , Contaminación del Aire Interior/estadística & datos numéricos , Monitoreo de Radiación/métodos , Radón/normas , Seguridad/normas , Contaminantes Radiactivos del Aire/análisis , Geología , Vivienda , Monitoreo de Radiación/normas , Radón/análisis , Incertidumbre
18.
J Environ Radioact ; 166(Pt 2): 382-389, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27158059

RESUMEN

The indoor radon concentration was measured in most houses in a couple of municipalities in Austria. At the same time the activity concentration of radium in soil, the soil gas radon concentration, the permeability of the ground and the ambient dose equivalent rate were also measured and the geological situations (geological units) were recorded too. From the indoor radon concentration and different house and living parameters a radon potential (Austrian radon potential) was derived which should represent the radon concentration in a standard room. Another radon potential (Neznal radon potential) was calculated from the soil gas radon concentration and the permeability. The aim of the investigation was to correlate all the different variables and to test if the use of surrogate data (e.g. geological information, ambient dose equivalent rate, etc.) can be used to judge the radon risk for an area without performing numerous indoor measurements.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/estadística & datos numéricos , Geología , Monitoreo de Radiación , Austria , Radón/análisis
19.
Nanotechnology ; 27(19): 195303, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-27040175

RESUMEN

Advanced synthesis of semiconductor nanowires (NWs) enables their application in diverse fields, notably in chemical and electrical sensing, photovoltaics, or quantum electronic devices. In particular, indium arsenide (InAs) NWs are an ideal platform for quantum devices, e.g. they may host topological Majorana states. While the synthesis has been continously perfected, only a few techniques have been developed to tailor individual NWs after growth. Here we present three wet chemical etch methods for the post-growth morphological engineering of InAs NWs on the sub-100 nm scale. The first two methods allow the formation of self-aligned electrical contacts to etched NWs, while the third method results in conical shaped NW profiles ideal for creating smooth electrical potential gradients and shallow barriers. Low temperature experiments show that NWs with etched segments have stable transport characteristics and can serve as building blocks of quantum electronic devices. As an example we report the formation of a single electrically stable quantum dot between two etched NW segments.

20.
J Neurol Sci ; 364: 29-32, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-27084211

RESUMEN

INTRODUCTION: Antibodies against neurofascin, an axo-glial protein located around the node of Ranvier, have been shown to contribute to axonal pathology both in vitro and in experimental autoimmune encephalomyelitis models. Moreover, small case studies have reported anti-NF antibodies in samples from patients with progressive multiple sclerosis (MS). PATIENTS AND METHODS: Building up on this observation, we compared the anti-NF reactivity in serum samples from 83 chronic progressive MS (PMS) patients to those with relapsing remitting MS (RRMS, n=159) and 50 healthy controls. Anti-NF seroreactivity was quantified by enzyme-linked immunosorbent assay using recombinant rat neurofascin. In addition, to identify a potential intrathecal anti-NF antibody synthesis, we calculated the specific antibody index in paired cerebrospinal fluid and serum samples from MS patients with positive anti-NF seroreactivity. RESULTS: Prevalence of anti-NF seroreactivity in PMS patients (4.8%; all with primary progressive MS) was significantly higher than that detected in RRMS (0.6%; p=0.030). However, we found no significant difference between PMS patients and healthy controls (2.0%; p=0.408). MS patients with positive anti-NF reactivity experienced an above-average progression of disability compared to MS natural-history controls. Anti-NF-specific intrathecal antibody synthesis was not detected in MS patients with positive anti-NF seroreactivity. CONCLUSIONS: Although present only in a minor subgroup, seroprevalence of anti-NF reactivity was significantly more frequent in patients with PMS than in those with RRMS, but was also occasionally found in healthy controls. Further prospective studies are warranted to investigate whether anti-NF antibodies anticipate disease progression.


Asunto(s)
Anticuerpos/sangre , Moléculas de Adhesión Celular/inmunología , Esclerosis Múltiple/sangre , Esclerosis Múltiple/inmunología , Factores de Crecimiento Nervioso/inmunología , Adulto , Distribución de Chi-Cuadrado , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estudios Seroepidemiológicos
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