4,539 research outputs found

    Measurement driven quantum evolution

    Full text link
    We study the problem of mapping an unknown mixed quantum state onto a known pure state without the use of unitary transformations. This is achieved with the help of sequential measurements of two non-commuting observables only. We show that the overall success probability is maximized in the case of measuring two observables whose eigenstates define mutually unbiased bases. We find that for this optimal case the success probability quickly converges to unity as the number of measurement processes increases and that it is almost independent of the initial state. In particular, we show that to guarantee a success probability close to one the number of consecutive measurements must be larger than the dimension of the Hilbert space. We connect these results to quantum copying, quantum deleting and entanglement generation.Comment: 7 pages, 1 figur

    Past and present of cystic echinococcosis in Bolivia

    Full text link
    Viable eggs of the canine intestinal tapeworm Echinococcus granulosus sensu lato (s.l.) infect various intermediate hosts causing cystic echinococcosis (CE). Furthermore, CE represents a serious zoonosis causing a significant global burden of disease. CE is highly endemic in South America, including Argentina, Brazil, Chile, Uruguay, and Peru. For Bolivia, no official data concerning the incidence in humans or the number of livestock and dogs infected are available. However, it is well known that CE occurs in Bolivia. We aim here to fill the gap in the current knowledge of the epidemiological situation of CE in Bolivia, providing a historical overview of documents published within the country, which have never been comprehensively reviewed. The very first documentation of E. granulosus infection in animals dates in 1910, while the first human case was reported in 1913. In total, 876 human CE cases have been reported in the scientific literature, with an apparent increase since the 1970s. In the absence of other epidemiological studies, the highest prevalence in human comes from Tupiza, Potosí Department, where 4.1% (51/1,268) of the population showed signs of CE at mass ultrasound screening in 2011. In the same report, 24% of dog faecal samples were positive for coproantigens of E. granulosus s.l. in ELISA. The highest prevalence in intermediate hosts reported at abattoir reached 37.5% in cattle from Potosí, followed by 26.9% in llamas from Oruro, 2.4% in pigs and 1.4% in sheep from La Paz. Finally, Echinococcus granulosus sensu stricto (s.s.), Echinococcus ortleppi (G5), and Echinococcus intermedius (G7) have been identified in Bolivia. Data reviewed here confirm that E. granulosus s.l. is circulating in Bolivia and that a proper prospective nationwide epidemiological study of CE is urgently needed to define transmission patterns as a basis for the planning and implementation of future control measurements

    Magnetic resonance imaging in the prenatal diagnosis of neural tube defects

    Get PDF
    OBJECTIVE: To assess the role of magnetic resonance imaging (MRI) in the prenatal diagnosis of neural tube defects (NTDs). BACKGROUND: NTDs comprise a heterogeneous group of congenital anomalies that derive from the failure of the neural tube to close. Advances in ultrasonography and MRI have considerably improved the diagnosis and treatment of NTDs both before and after birth. Ultrasonography is the first technique in the morphological study of the fetus, and it often makes it possible to detect or suspect NTDs. Fetal MRI is a complementary technique that makes it possible to clear up uncertain ultrasonographic findings and to detect associated anomalies that might go undetected at ultrasonography. The progressive incorporation of intrauterine treatments makes an accurate diagnosis of NTDs essential to ensure optimal perinatal management. The ability of fetal MRI to detect complex anomalies that affect different organs has been widely reported, and it can be undertaken whenever NTDs are suspected. CONCLUSION: We describe the normal appearance of fetal neural tube on MRI, and we discuss the most common anomalies involving the structures and the role of fetal MRI in their assessment. KEY POINTS: • To learn about the normal anatomy of the neural tube on MRI • To recognise the MR appearance of neural tube defects • To understand the value of MRI in assessing NTD

    Adhesión de osteoblastos sobre andamios de PLA-PLG- biocerámico-colágeno, fotosensibilizados con luz UV

    Get PDF
    ResumenEmpleando simultáneamente, las técnicas de Espectroscopia de Impedancia Electroquímica (EIE) y Microbalanza de Cristal de Cuarzo (MCC) en una celda de tres electrodos, bajo condiciones de bioseguridad y adicionando una concentración de 60000células/ml de osteoblastos, con 2ml de medio celular, fue evaluada la adhesión celular sobre películas delgadas de polímeros (PLA-PGA) con 10% de biocerámicos de hidroxiapatita y fosfato tricálcico (HAP, TCP-β). Estas películas fueron obtenidas por electrodeposición catódica sobre un sustrato de Ti6Al4V ELI y sobre cristales de cuarzo con Au- Ti. Estos materiales, luego fueron modificados superficialmente con colágeno disuelto, pipeteado homogéneamente sobre la superficie polimérica en concentraciones de 10μg/ml y 20μg/ml y luego, fueron irradiados con luz ultravioleta durante 10 minutos. Observaciones de Microscopía electrónica sellevaron a cabo para estudiar la morfología superficial, comprobando una mayor adhesión por el efectode la fotoxidación por irradiación UV. Palabras clave: ingeniería de tejidos, irradiación ultravioleta, adhesión celular, espectroscopia de impedancia electroquímica, microbalanza de cristal de cuarzo. Osteoblast adhesion on PLA-PLG bioceramic- collagen scaffolds, photosensitized UV light  Abstract Simultaneously using the techniques of Electrochemical Impedance Spectroscopy ( EIS ) and quartz crystal microbalance (MCC) in a three-electrode cell under conditions of biosafety and adding a concentration of 60000cells/ml of osteoblasts , with 2ml of medium cell was evaluated cell adhesion on thin films of polymers (PLA -PGA) bioceramic 10% tricalcium phosphate and hydroxyapatite (HAP , TCP - β ) . These films were obtained by cathodic electrodeposition on ELI Ti6Al4V substrate and quartz crystals with Au –Ti. These materials were then surface modified with dissolved collagen, pipetting homogeneously on the polymer surface at concentrations of 10μg/ml and 20μg/ml and then they were irradiated with UV light for 10minutes. Electron microscopy observations were carried out to study the surface morphology, ensuring greater adherence by the effect of photo-oxidation by UV irradiation. Keywords: tissue engineering, ultraviolet irradiation, cell adhesion, electrochemical impedance spectroscopy, quartz crystal microbalance.  Adesão de osteoblastos no andaime PLA-PLG- biocerâmica-colágeno, fotossensibilizada com luz UV   Resumo  Simultaneamente, utilizando as técnicas de espectroscopia de impedância electroquímica (EIA) e microbalança de cristal de quartzo (MCC), em uma célula de três eléctrodos em condições de segurança biológica e a adição de uma concentração de 60000células/ml de osteoblastos, com 2ml de meio de células foi avaliada a adesão celular em filmes finos de polímeros (PLA-PGA) biocerâmica 10% fosfato tricálcico e hidroxiapatita (HAP, TCP - β). Estes filmes foram obtidos por electrodeposição catódica em ELI Ti6Al4V substrato de quartzo e cristais com Au-Ti. Estes materiais foram então superfície modificada com dissolvido colagénio, pipetagem homogeneamente na superfície do polímero em concentrações de 10μg/ml e 20μg/ml e, em seguida, foram irradiadas com luz UV durante 10 minutos. Observações de microscopia eletrônica foram realizados para estudar a morfologia da superfície, garantindo maior aderência pelo efeito da foto-oxidação por irradiação UV.    Palabras-chave: engenharia de tecidos, a irradiação ultravioleta, adesão celular, espectroscopia de impedância eletroquímica, cristal de quartzo microbalance.      Cita: Estupiñan Duran HA, Peña Ballesteros DY, Martínez NM. Adhesión de osteoblastos sobre andamios de PLA-PLG-biocerámico- colágeno, fotosensibilizados con luz UV. rev.ion. 2014;27(2): 7-15

    Adhesión de osteoblastos sobre andamios de PLA-PLG- biocerámico-colágeno, fotosensibilizados con luz UV

    Get PDF
    ResumenEmpleando simultáneamente, las técnicas de Espectroscopia de Impedancia Electroquímica (EIE) y Microbalanza de Cristal de Cuarzo (MCC) en una celda de tres electrodos, bajo condiciones de bioseguridad y adicionando una concentración de 60000células/ml de osteoblastos, con 2ml de medio celular, fue evaluada la adhesión celular sobre películas delgadas de polímeros (PLA-PGA) con 10% de biocerámicos de hidroxiapatita y fosfato tricálcico (HAP, TCP-β). Estas películas fueron obtenidas por electrodeposición catódica sobre un sustrato de Ti6Al4V ELI y sobre cristales de cuarzo con Au- Ti. Estos materiales, luego fueron modificados superficialmente con colágeno disuelto, pipeteado homogéneamente sobre la superficie polimérica en concentraciones de 10μg/ml y 20μg/ml y luego, fueron irradiados con luz ultravioleta durante 10 minutos. Observaciones de Microscopía electrónica sellevaron a cabo para estudiar la morfología superficial, comprobando una mayor adhesión por el efectode la fotoxidación por irradiación UV. Palabras clave: ingeniería de tejidos, irradiación ultravioleta, adhesión celular, espectroscopia de impedancia electroquímica, microbalanza de cristal de cuarzo. Osteoblast adhesion on PLA-PLG bioceramic- collagen scaffolds, photosensitized UV light  Abstract Simultaneously using the techniques of Electrochemical Impedance Spectroscopy ( EIS ) and quartz crystal microbalance (MCC) in a three-electrode cell under conditions of biosafety and adding a concentration of 60000cells/ml of osteoblasts , with 2ml of medium cell was evaluated cell adhesion on thin films of polymers (PLA -PGA) bioceramic 10% tricalcium phosphate and hydroxyapatite (HAP , TCP - β ) . These films were obtained by cathodic electrodeposition on ELI Ti6Al4V substrate and quartz crystals with Au –Ti. These materials were then surface modified with dissolved collagen, pipetting homogeneously on the polymer surface at concentrations of 10μg/ml and 20μg/ml and then they were irradiated with UV light for 10minutes. Electron microscopy observations were carried out to study the surface morphology, ensuring greater adherence by the effect of photo-oxidation by UV irradiation. Keywords: tissue engineering, ultraviolet irradiation, cell adhesion, electrochemical impedance spectroscopy, quartz crystal microbalance.  Adesão de osteoblastos no andaime PLA-PLG- biocerâmica-colágeno, fotossensibilizada com luz UV   Resumo  Simultaneamente, utilizando as técnicas de espectroscopia de impedância electroquímica (EIA) e microbalança de cristal de quartzo (MCC), em uma célula de três eléctrodos em condições de segurança biológica e a adição de uma concentração de 60000células/ml de osteoblastos, com 2ml de meio de células foi avaliada a adesão celular em filmes finos de polímeros (PLA-PGA) biocerâmica 10% fosfato tricálcico e hidroxiapatita (HAP, TCP - β). Estes filmes foram obtidos por electrodeposição catódica em ELI Ti6Al4V substrato de quartzo e cristais com Au-Ti. Estes materiais foram então superfície modificada com dissolvido colagénio, pipetagem homogeneamente na superfície do polímero em concentrações de 10μg/ml e 20μg/ml e, em seguida, foram irradiadas com luz UV durante 10 minutos. Observações de microscopia eletrônica foram realizados para estudar a morfologia da superfície, garantindo maior aderência pelo efeito da foto-oxidação por irradiação UV.    Palabras-chave: engenharia de tecidos, a irradiação ultravioleta, adesão celular, espectroscopia de impedância eletroquímica, cristal de quartzo microbalance.      Cita: Estupiñan Duran HA, Peña Ballesteros DY, Martínez NM. Adhesión de osteoblastos sobre andamios de PLA-PLG-biocerámico- colágeno, fotosensibilizados con luz UV. rev.ion. 2014;27(2): 7-15

    Large Mitochondrial DNA Deletion in an Infant with Addison Disease

    Get PDF
    Abstract Background: Mitochondrial diseases are a group of disorders caused by mutations in nuclear DNA or mitochondrial DNA, usually involving multiple organ systems. Primary adrenal insufficiency due to mitochondrial disease is extremely infrequent and has been reported in association with mitochondrial DNA deletion syndromes such as Kearns-Sayre syndrome. Aim: To report a 3-year-old boy with Addison disease, congenital glaucoma, chronic pancreatitis, and mitochondrial myopathy due to large mitochondrial DNA deletion. Method: Molecular analysis of mitochondrial DNA samples obtained from peripheral blood, oral mucosa, and muscle tissue. Results: A novel large mitochondrial DNA deletion of 7,372 bp was identified involving almost all genes on the big arch of mtDNA. Conclusions: This case reaffirms the association of adrenal insufficiency and mitochondrial DNA deletions and presents new evidence that glaucoma is another manifestation of mitochondrial diseases. Due to the genetic and clinical heterogeneity of mitochondrial disorders, molecular analysis is crucial to confirm diagnosis and to allow accurate genetic counseling

    In vitro and in vivo regulation of ß-Adrenoceptors signaling using synthetic light-regulated molecules

    Get PDF
    Beta-adrenoceptors (ß-AR) are prototypical G protein-coupled receptors (GPCR) and important pharmacological targets for numerous diseases. Indeed, a number of approved drugs target ß-AR, which are key regulators of many physiological functions. Among other examples, ß1-AR antagonists (known as ß-Blockers) are first-line therapies for the treatment of heart failure, and ß2-AR agonists, which act as bronchodilators, are widely used for the treatment of breathing pathologies. Considering the medical relevance of these receptors, achieving a reversible and localized control of their activity would provide a powerful research and clinical tool. GPCR signaling is currently recognized as a multidimensional process governed by molecular, spatial and temporal components. Uncovering the role of each of these dimensions is crucial to improve our knowledge on cell communication, to understand how different pathways give rise to cellular and physiological effects, and to know how can we interact with biological systems with precision using drugs. Photopharmacology is an emerging field in which light-sensitive molecules are used to control the function of a given target protein in native tissues. The modulation of the target activity is achieved by small, drug-like, photoregulated ligands. By the use of light, both spatial and temporal control of the compound activity can be achieved in unprecedented manners compared to conventional pharmacology. These ligands have the potential to provide highly precise and controllable therapeutic actions that may result in increased efficacies and reduced side effects. Importantly, photopharmacology may allow to gain mechanistic insight on the interplay between the activation time and the receptor location during signaling processes in non-modified cells, tissues and whole organisms. Our research focused on the generation of new molecular tools for beta-adrenoceptors photopharmacology will be presented in this communication. First, several libraries of light-sensitive compounds with the aim to regulate ß-AR activity with spatiotemporal precision were designed and synthesized. Subsequent testing in cell preparations demonstrated the successful development of compounds with promising pharmacological properties, which can be reversibly and irreversibly controlled by light. Among those, several hit compounds were identified as ligands for beta-1 and beta-2 adrenoceptors with low nanomolar activities. These libraries compounds were found to be active enough to become useful photopharmacological tools, so we also performed in vivo experiments to determine their research potential in physiological environments. Indeed, the discovered molecules enabled a fine control of ß-AR in their native environment. We believe that the results of these studies will certainly open the door to innovative research procedures and may inspire future therapies targeting ß-AR

    The highly prevalent BRCA2 mutation c.2808_2811del (3036delACAA) is located in a mutational hotspot and has multiple origins

    Get PDF
    BRCA2-c.2808_2811del (3036delACAA) is one of the most reported germ line mutations in non-Ashkenazi breast cancer patients. We investigated its genetic origin in 51 Spanish carrier families that were genotyped with 11 13q polymorphic markers. Three independent associated haplotypes were clearly distinguished accounting for 23 [west Castilla y León (WCL)], 20 [east Castilla y León (ECL)] and 6 (South of Spain) families. Mutation age was estimated with the Disequilibrium Mapping using Likelihood Estimation software in a range of 45–68 and 45–71 generations for WCL and ECL haplotypes, respectively. The most prevalent variants, c.2808_2811del and c.2803G > A, were located in a double-hairpin loop structure (c.2794–c.2825) predicted by Quikfold that was proposed as a mutational hotspot. To check this hypothesis, random mutagenesis was performed over a 923 bp fragment of BRCA2, and 86 DNA variants were characterized. Interestingly, three mutations reported in the mutation databases (c.2680G > A, c.2944del and c.2957dup) were replicated and 20 affected the same position with different nucleotide changes. Moreover, five variants were placed in the same hairpin loop of c.2808_2811del, and one affected the same position (c.2808A > G). In conclusion, our results support that at least three different mutational events occurred to generate c.2808_2811del. Other highly prevalent DNA variants, such as BRCA1-c.68_69delAG, BRCA2- c.5946delT and c.8537delAG, are concentrated in hairpin loops, suggesting that these structures may represent mutational hotspots

    Measurement of the (90,91,92,93,94,96)Zr(n,gamma) and (139)La(n,gamma) cross sections at n_TOF

    Get PDF
    Open AccessNeutron capture cross sections of Zr and La isotopes have important implications in the field of nuclear astrophysics as well as in the nuclear technology. In particular the Zr isotopes play a key role for the determination of the neutron density in the He burning zone of the Red Giant star, while the (139)La is important to monitor the s-process abundances from Ba up to Ph. Zr is also largely used as structural materials of traditional and advanced nuclear reactors. The nuclear resonance parameters and the cross section of (90,91,92,93,94,96)Zr and (139)La have been measured at the n_TOF facility at CERN. Based on these data the capture resonance strength and the Maxwellian-averaged cross section were calculated

    Present Status and Future Programs of the n_TOF Experiment

    Get PDF
    This is an Open Access article distributed under the terms of the Creative Commons Attribution-Noncommercial License 3.0, which permits unrestricted use, distribution, and reproduction in any noncommercial medium, provided the original work is properly citedThe neutron time-of-flight facility n_TOF at CERN, Switzerland, operational since 2001, delivers neutrons using the Proton Synchrotron (PS) 20 GeV/c proton beam impinging on a lead spallation target. The facility combines a very high instantaneous neutron flux, an excellent time of flight resolution due to the distance between the experimental area and the production target (185 meters), a low intrinsic background and a wide range of neutron energies, from thermal to GeV neutrons. These characteristics provide a unique possibility to perform neutron-induced capture and fission cross-section measurements for applications in nuclear astrophysics and in nuclear reactor technology.The most relevant measurements performed up to now and foreseen for the future will be presented in this contribution. The overall efficiency of the experimental program and the range of possible measurements achievable with the construction of a second experimental area (EAR-2), vertically located 20 m on top of the n_TOF spallation target, might offer a substantial improvement in measurement sensitivities. A feasibility study of the possible realisation of the installation extension will be also presented
    corecore