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1.
Nat Commun ; 14(1): 3968, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37407570

RESUMEN

Currently available quantum processors are dominated by noise, which severely limits their applicability and motivates the search for new physical qubit encodings. In this work, we introduce the inductively shunted transmon, a weakly flux-tunable superconducting qubit that offers charge offset protection for all levels and a 20-fold reduction in flux dispersion compared to the state-of-the-art resulting in a constant coherence over a full flux quantum. The parabolic confinement provided by the inductive shunt as well as the linearity of the geometric superinductor facilitates a high-power readout that resolves quantum jumps with a fidelity and QND-ness of >90% and without the need for a Josephson parametric amplifier. Moreover, the device reveals quantum tunneling physics between the two prepared fluxon ground states with a measured average decay time of up to 3.5 h. In the future, fast time-domain control of the transition matrix elements could offer a new path forward to also achieve full qubit control in the decay-protected fluxon basis.

2.
Nat Commun ; 11(1): 5024, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33004799

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Nat Commun ; 11(1): 4460, 2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32901014

RESUMEN

Practical quantum networks require low-loss and noise-resilient optical interconnects as well as non-Gaussian resources for entanglement distillation and distributed quantum computation. The latter could be provided by superconducting circuits but existing solutions to interface the microwave and optical domains lack either scalability or efficiency, and in most cases the conversion noise is not known. In this work we utilize the unique opportunities of silicon photonics, cavity optomechanics and superconducting circuits to demonstrate a fully integrated, coherent transducer interfacing the microwave X and the telecom S bands with a total (internal) bidirectional transduction efficiency of 1.2% (135%) at millikelvin temperatures. The coupling relies solely on the radiation pressure interaction mediated by the femtometer-scale motion of two silicon nanobeams reaching a Vπ as low as 16 µV for sub-nanowatt pump powers. Without the associated optomechanical gain, we achieve a total (internal) pure conversion efficiency of up to 0.019% (1.6%), relevant for future noise-free operation on this qubit-compatible platform.

4.
Sci Adv ; 6(18): eaba0412, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32494686

RESUMEN

Sensing-actuation systems can assist a bladder with lost sensation and weak muscle control. Here, we advance the relevant technology by integrating a soft and thin capacitive sensor with a shape memory alloy-based actuator to achieve a high-performance closed-loop configuration. In our design, sensors capable of continuous bladder volume detection and actuators with strong emptying force have been used. This integration has previously hindered performance due to large bladder volume changes. Our solution integrates sensing-actuation elements that are bladder compatible but do not interfere with one another, achieving real-time bladder management. The system attains a highly desirable voiding target of 71 to 100% of a rat's bladder with a volume sensitivity of 0.7 µF/liter. Our system represents an efficient voiding solution that avoids overfilling and represents a technological solution to bladder impairment treatment, serving as a model for similar soft sensor-actuator integration with other organs.

7.
J Plast Reconstr Aesthet Surg ; 72(6): 918-923, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30880049

RESUMEN

Many factors have been proposed to contribute to the risk of recurrent tenosynovial giant cell tumours (TSGCT); however, we remain unable to predict those at risk, which formed the rationale for this multicentre retrospective case-control study of 28 patients with recurrence. We included cases of recurrence in a 1:1 ratio matched for age and sex with controls over 10 years. Using Cox regression, we present hazard ratios (HRs) for recurrence with 95% confidence intervals (CIs). Out of 285 cases, 28 individuals developed recurrence after a median of 2.4 years. Recurrent TSGCT had a higher mitotic count/mm2 in the primary tumour (median increase of 3 [IQR 1, 7]). Mitotic count in the primary tumour was associated with the risk of recurrence (adjusted HR 1.1 [95% CI 1.1, 1.2]) meaning that for every additional mitosis, the risk of recurrence increased by 10% per annum. We recommend a prospective cohort study to validate our findings.


Asunto(s)
Disección , Tumor de Células Gigantes de las Vainas Tendinosas , Índice Mitótico/métodos , Recurrencia Local de Neoplasia , Adulto , Factores de Edad , Estudios de Casos y Controles , Disección/efectos adversos , Disección/métodos , Femenino , Tumor de Células Gigantes de las Vainas Tendinosas/patología , Tumor de Células Gigantes de las Vainas Tendinosas/cirugía , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/epidemiología , Evaluación de Resultado en la Atención de Salud , Radioterapia/efectos adversos , Radioterapia/métodos , Estudios Retrospectivos , Medición de Riesgo/métodos , Factores Sexuales
8.
Andrologia ; 46(10): 1118-27, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24313687

RESUMEN

This study evaluates the relationship between sperm intracellular reactive oxygen species (ROS; H2 O2 , O2 ), DNA fragmentation (DF), low mitochondria membrane potential (MMP) of sperm and normal pronuclear formation among intracytoplasmic sperm injection (ICSI) patients. Semen samples were obtained from 62 infertile male who were candidates for ICSI treatment. After sperm processing, metaphase II (MII) oocytes were injected, and the mean percentages of intracellular ROS, MMP and DF were evaluated using flow cytometry. The mean percentages of pronuclear formation and zygote score (Z) were also recorded, and Pearson, Spearman's rank correlation coefficient and Kruskal-Wallis tests were applied to analyse the data. The amounts of sperm intracellular H2 O2 and O2-˙ had significant positive correlation with low MMP (P < 0.01). The intracellular ROS had a negative correlation with pronuclear formation (P < 0.05), and its effect was higher than 66.66%. In addition, the mean percentages of neither H2 O2 nor O2-˙ affected the quality of pronuclear embryos (Z-score). This study shows that although high levels of both sperm intracellular H2 O2 and O2-˙ in ICSI patients have deleterious effect on sperm MMP, only H2 O2 may interfere in pronuclear formation.


Asunto(s)
Desarrollo Embrionario/fisiología , Infertilidad Masculina/metabolismo , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides/metabolismo , Fragmentación del ADN , Femenino , Humanos , Masculino
9.
Plant Dis ; 98(12): 1739, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30703900

RESUMEN

The causal agent of Asiatic citrus canker, Xanthomonas citri pv. citri, is a bacterium of major economic importance in tropical and subtropical citrus-producing areas. X. citri pv. citri pathotype A can cause severe infection in a wide range of citrus species and induces erumpent, callus-like lesions with water-soaked margins evolving to corky cankers and leading to premature fruit, leaf drop, and twig dieback on susceptible cultivars. This quarantine organism can strongly impact citrus markets so it has consequently been subjected to eradication efforts and international quarantine regulations. Asiatic citrus canker occurs on most islands in the Southwest Indian Ocean region including the Mascarene and Seychelles archipelagos. In the Comoros archipelago, the disease was observed for the first time in Mohéli island in 1966 (2), but had not yet been reported in neighboring islands, Grande Comore and Anjouan. In September 2013, leaves of key lime (Citrus aurantifolia) and sweet orange (C. sinensis) showing symptoms of citrus canker were collected from Anjouan, Grande Comore, and Mohéli. Nine Xanthomonas-like strains (three from each of the three islands) were isolated using KC semi-selective medium (5) from diseased samples (LK126-3, LK127-7, LK128-2, LK131-10, LK137-1, LK141-3, LK144-5, LK145-5, LK146-2). Based on a specific PCR assay with 4/7 primers (4), all Xanthomonas-like strains were tentatively identified as X. citri pv. citri. All strains produced a 468-bp amplicon similar to X. citri pv. citri strain IAPAR 306 used as a positive control. Negative control reactions with sterile tris buffer did not produce amplicons. Multilocus sequence analysis (MLSA) targeting six housekeeping genes (atpD, dnaK, efp, gltA, gyrB, and lepA) (1,3) fully identified all strains from the Comoros as X. citri pv. citri. More specifically, eight strains were identified as sequence type ST2 composed of pathotype A strains of X. citri pv. citri (3) (including all strains from the Southwest Indian Ocean region) while one of them (LK141-3 from Mohéli) was identified as a new sequence type based on a non-synonymous single nucleotide polymorphism in gyrB (accession KJ941208). All strains were inoculated by a detached leaf assay (3) onto Mexican lime SRA 140 (C. aurantifolia), Tahiti lime SRA 58 (C. latifolia), sweet orange New Hall Navel SRA 343 (C. sinensis), grapefruit Henderson SRA 336 (C. paradisi), and Ortanique tangor SRA 110 (C. reticulata × C. sinensis). All citrus species inoculated produced typical erumpent, callus-like tissue at wound sites. Xanthomonas-like yellow colonies were re-isolated from lesions produced on Mexican lime. Boiled bacterial suspensions were assayed by PCR with 4/7 primers (4) and produced the expected amplicon, fulfilling Koch's postulates. No lesions developed on the negative control consisting of inoculations with sterile tris buffer. This is the first report of X. citri pv. citri-A causing Asiatic citrus canker in Grande Comore and Anjouan islands confirming the wide distribution of the pathogen in Southwest Indian Ocean islands. Canker-free nurseries and grove sanitation should be implemented to decrease the prevalence of Asiatic canker in the Comoros. References: (1) N. F. Almeida et al. Phytopathology 100:208, 2010. (2) J. Brun. Fruits 26:533, 1971. (3) L. Bui Thi Ngoc et al. Int. J. Syst. Evol. Microbiol. 60:515, 2010. (4) J. S. Hartung et al. Phytopathology 86:95, 1996. (5) O. Pruvost et al. J. Appl. Microbiol. 99:803, 2005.

10.
Neurochirurgie ; 58(4): 254-7, 2012 Aug.
Artículo en Francés | MEDLINE | ID: mdl-22464603

RESUMEN

The cerebral atypical rhabdoid/teratoid tumor constitutes one of the most aggressive tumors of children. Such tumors are equally characterized by a critically and speedly mortal development. The optimal management of such tumors remains unknown. The authors report two cases of cerebral atypical rhabdoid teratoid tumor in 8- and 10-year girls and discuss the histological features, immunochemistry study, prognosis and treatment of these rare tumors.


Asunto(s)
Neoplasias Encefálicas/patología , Tumor Rabdoide/patología , Teratoma/patología , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Niño , Femenino , Proteína Ácida Fibrilar de la Glía/inmunología , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Antígeno Ki-67/inmunología , Antígeno Ki-67/metabolismo , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia , Procedimientos Neuroquirúrgicos , Pronóstico , Tumor Rabdoide/radioterapia , Tumor Rabdoide/cirugía , Teratoma/radioterapia , Teratoma/cirugía
11.
J Hand Surg Eur Vol ; 34(4): 530-6, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19587081

RESUMEN

The purpose of our study was to evaluate a new region-specific outcome measure in hand and upper limb surgery: the Patient Outcomes of Surgery (POS)-Hand/Arm questionnaire using the generic Short Form Health Survey (SF)-36 questionnaire as a 'gold standard' comparative measure. The POS-Hand/Arm preop questionnaire and the SF-36 questionnaire were completed by 214 patients on the day of their hand or upper limb surgery; and a postop POS-Hand/Arm and the SF-36 questionnaire were completed by patients 3 months after their initial surgery. The POS-Hand/Arm questionnaire responses were psychometrically evaluated and it was shown to have high internal consistency; high total-item correlations; signification scale correlations with the SF-36; and a low proportion of missing data. The POS-Hand/Arm questionnaire is a psychometrically sound instrument that can be used pre- and post-surgery to evaluate patient-based outcomes for a wide range of conditions in hand and upper limb surgery.


Asunto(s)
Brazo/cirugía , Mano/cirugía , Satisfacción del Paciente , Complicaciones Posoperatorias/diagnóstico , Encuestas y Cuestionarios , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Psicometría/estadística & datos numéricos , Reproducibilidad de los Resultados , Resultado del Tratamiento , Adulto Joven
12.
J Hazard Mater ; 170(2-3): 779-85, 2009 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-19482423

RESUMEN

In this study, changes in viability, biomass production, essential oil yield and essential oil composition of Mentha spicata L. (spearmint) exposed to olive mill wastewater (OMW) were investigated. Spearmint cuttings were sensitive to OMW and, after 6h of incubation in raw or diluted OMW, their viability was null. The short contact of raw OMW with mint cuttings caused an irreversible damage in rhizogenesis and shoots development. Roots were more sensitive to phytotoxicity than shoots. In a field essay, spearmint showed a good capability to recover when OMW was spread at 8 l m(-2) at the vegetative phase of growth (45 days after plantation). At this dose, a slight increase of mostly of the mint essential oil constituents was obtained. When the dose applied was 16 l m(-2), phytotoxicity was manifested by a high reduction of biomass and essential oil yield. The essential oil composition was also affected and a disappearance of many of mint essential oil constituents was observed with an increase of 59% for carvone, the major compound of spearmint essential oil. As far as we know, this is the first report on the effect of field application of OMW on an aromatic plant essential oil yield and composition.


Asunto(s)
Industria de Procesamiento de Alimentos , Residuos Industriales/efectos adversos , Mentha spicata/crecimiento & desarrollo , Olea/química , Biomasa , Mentha spicata/efectos de los fármacos , Mentha spicata/metabolismo , Aceites Volátiles/análisis , Fenoles/química , Fenoles/toxicidad , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Cloruro de Sodio , Eliminación de Residuos Líquidos , Agua/análisis
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