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1.
Opt Express ; 31(4): 5414-5425, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823822

RESUMO

We report a directly modulated distributed feedback laser operating in gain-switching mode for preparing the coherent states required for the Gaussian-modulated coherent-state (GMCS) continuous-variable quantum key distribution (CV-QKD) protocol. The proposed single-component quantum transmitter design eliminates the need for external modulators, decreasing the complexity of GMCS CV-QKD systems. The experimental results demonstrate a potential asymptotic secret key rate value of 2.63 Mbps over an 11-km fiber link, making the directly modulated GMCS transmitter particularly suitable for metropolitan optical networks where compactness, robustness, and low cost are key desirable features.

2.
Opt Express ; 29(10): 14815-14827, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985195

RESUMO

We present a versatile transmitter capable of performing both discrete variable and continuous variable quantum key distribution protocols (DV-QKD and CV-QKD, respectively). Using this transmitter, we implement a time-bin encoded BB84 DV-QKD protocol over a physical quantum channel of 47 km and a GG02 CV-QKD protocol with true local oscillator over a 10.5 km channel, achieving secret key rates of 4.1 kbps and 1 Mbps for DV- and CV-QKD, respectively. The reported transmitter scheme is particularly suitable for re-configurable optical networks where the QKD protocol is selected to optimize the performance according to the parameters of the links.

3.
Opt Express ; 28(10): 14547-14559, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403493

RESUMO

We report a plug-and-play continuous variable quantum key distribution system (CV-QKD) with Gaussian modulated quadratures and a true local oscillator. The proposed configuration avoids the need for frequency locking two narrow line-width lasers. To minimize Rayleigh back-scattering, we utilize two independent fiber strands for the distribution of the laser and the transmission of the quantum signals. We further demonstrate the quantum-classical co-existing capability of our system by injecting high-power classical light in both fibers. A secret key rate up to 0.88 Mb/s is obtained by using two fiber links of 13 km and up to 0.3 Mb/s when adding 4 mW of classical light in the optical fiber used for transmitting the quantum signal. The reported performance indicates that the proposed QKD scheme has the potential to become an effective low-cost solution for metropolitan optical networks.

5.
Rev. esp. investig. quir ; 13(3): 135-136, jul.-sept. 2010. ilus
Artigo em Espanhol | IBECS | ID: ibc-89047

RESUMO

La intervención sobre un aneurisma de aorta roto conlleva una celeridad y eficacia de los movimientos quirúrgicos. Sin embargo, esto puede en ocasiones ser fuente de complicaciones nada desdeñables, a veces facilitadas por la dificultad para reconocer estructuras en el seno de grandes hematomas. Las lesiones venosas iatrogénicas son infrecuentes en manos expertas, pero son por lo general relevantes en el pronóstico inmediato (AU)


The intervention of a ruptured aortic aneurysm involves rapid and effective surgical movements. However, it can be a source of serious complications, sometimes facilitated by the difficulty to differentiate anatomical structures within large hematomas. Iatrogenic venous injuries are uncommon in experienced hands, but are generally relevant in the immediate prognosis (AU)


Assuntos
Humanos , Ruptura Aórtica/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Artéria Ilíaca/cirurgia , Doença Iatrogênica/prevenção & controle
6.
Anal Chim Acta ; 587(2): 222-34, 2007 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-17386777

RESUMO

Six sulfamides were extracted from kidney and analysed by high-performance liquid chromatography with diode array detection (HPLC-DAD): sulfadiazine, sulfamethazine, sulfamethoxypyridazine, sulfamethoxazole, sulfadimethoxine and sulfaquinoxaline. Two main difficulties arose in identifying and quantifying the analytes. Firstly, the chromatographic peaks of the matrix interferences overlapped with those of the analytes. The uniqueness property of PARAFAC2 solved this problem. Secondly, the gradient elution caused a baseline drift. The first-order derivative of the chromatograms minimized its effect. The analytical method was validated. As the performance criteria detailed in the European Decision 2002/657/EC are based on specific signals, this paper generalizes those criteria for higher-order and non-specific signals. In this sense the proposed methodology is general and can be applied to any chromatographic method (HPLC or GC) with a detector that provide a multivariate signal (MS, DAD, EC, etc.).


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia/métodos , Rim/metabolismo , Sulfonamidas/análise , Animais , Resíduos de Drogas/análise , Humanos , Rim/efeitos dos fármacos , Modelos Químicos , Modelos Estatísticos , Análise de Regressão , Reprodutibilidade dos Testes , Software , Espectrofotometria Ultravioleta/métodos , Sulfonamidas/química , Suínos
7.
J Chromatogr A ; 1085(2): 190-8, 2005 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-16106698

RESUMO

An analytical method has been developed to extract ciprofloxacin and enrofloxacin from eggs. The aim of this work is to determine the experimental conditions of extraction providing high recoveries with small standard deviations. An experimental design based on the D-optimality criterion and replicated three times was built to evaluate the effect of five factors related to the extraction which is the most inaccurate stage of the procedure. This non-classical design is needed because there are several practical constraints: (i) the extraction procedure is time-consuming, quinolones are not stable and the design must be performed in a single working session. (ii) The tube capacity of the centrifuge is 6, so the number of experiments will be 6 or a multiple of 6. In the optimal experimental conditions, the extraction is performed once with 5 ml of methanol. Then, fatty acids are removed with a mixture of hexane/ether. Analytes are finally separated and detected by HPLC-fluorescence without the additional step of purification by solid-phase extraction (SPE). Under these conditions, the mean recovery is 64% and 70% and the standard deviation 5% and 4% for ciprofloxacin and enrofloxacin, respectively. The capability of decision, CCalpha, is 3.1 and 2.8 microg kg(-1) of ciprofloxacin and enrofloxacin, respectively. The capability of detection, CCbeta, is 7.8 and 7.0 microg kg(-1) of ciprofloxacin and enrofloxacin, respectively. In both cases the probabilities of false positive, alpha, and of false negative, beta, were fixed at 0.05.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ciprofloxacina/análise , Ovos/análise , Fluoroquinolonas/análise , Algoritmos , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Enrofloxacina , Reprodutibilidade dos Testes
8.
Analyst ; 129(8): 766-71, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15284923

RESUMO

The robustness of a multiresidue method has been analysed for the extraction and quantification of sulfamethoxypyridazine, sulfamethoxazole and sulfadimethoxine in porcine kidney by HPLC-DAD through a Plackett-Burman design. Two experimental responses were examined, the mean recovery from three replicates (accuracy) and their standard deviation (precision). Three factors were tested: the volume of phosphoric acid (pH) added in the extraction step, the time used for passing the sample through the solid-phase extraction cartridge (flow rate) and methanol volume to elute the analytes from the cartridge. Due to the non-specificity of the chromatograms (unknown matrix interferences coelute with each sulfonamide) the PARAFAC model was employed to evaluate the concentration recovered in the experiments of the Plackett-Burman design as well as to identify the spectra of the substances according to the criteria set in the European Decision 2002/657/EC for the analysis of residues. The extraction step was concluded to be robust to the recovery and the standard deviation of all three analytes.


Assuntos
Resíduos de Drogas/análise , Análise Fatorial , Rim/química , Sulfonamidas/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Sensibilidade e Especificidade , Suínos
9.
J Wildl Dis ; 30(1): 65-8, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8151826

RESUMO

A combination of the dissociative anesthetic ketamine hydrochloride (KH) and the sedative xylazine hydrochloride (XH) was used to immobilize 31 wild Iberian lynx (Felis pardina) 45 times at Doñana National Park, Spain. A mean (+/- SE) dose of 4.6 (+/- 0.2) mg/kg KH and 4.0 (+/- 0.2) mg/kg XH resulted in mean (+/- SE) induction time of 5.6 (+/- 0.3) min and mean (+/- SE) first reaction time of 59.3 (+/- 6.5) min. Convulsions occurred four times (9%), but with no noteworthy consequences.


Assuntos
Animais Selvagens/fisiologia , Carnívoros/fisiologia , Imobilização , Ketamina , Xilazina , Animais , Temperatura Corporal , Combinação de Medicamentos , Feminino , Frequência Cardíaca , Injeções Intramusculares/veterinária , Ketamina/administração & dosagem , Ketamina/efeitos adversos , Masculino , Análise de Regressão , Respiração , Convulsões/induzido quimicamente , Convulsões/veterinária , Espanha , Fatores de Tempo , Xilazina/administração & dosagem , Xilazina/efeitos adversos
10.
J Wildl Dis ; 28(3): 507-9, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1512894

RESUMO

A combination of xylazine hydrochloride-ketamine hydrochloride was used to immobilize 83 wild red foxes (Vulpes vulpes) (15 pups and 68 adults) at Doñana National Park (Spain). Mean ketamine hydrochloride doses were 17.1 mg/kg (SE = 1.53) and 12.3 mg/kg (SE = 0.4) for pups and adults, respectively, and mean xylazine hydrochloride doses for the same groups were 6.2 mg/kg (SE = 0.63) and 4.7 mg/kg (SE = 0.14), respectively. Mean induction times and first reaction times were 1.6 minutes and 22.5 minutes for pups and 3.8 minutes and 39.4 minutes for adults, respectively. Recommended doses for wild adult foxes of unknown weight are 75 mg of ketamine hydrochloride and 20 mg of xylazine hydrochloride.


Assuntos
Animais Selvagens/fisiologia , Raposas/fisiologia , Imobilização , Ketamina , Xilazina , Animais , Feminino , Masculino , Gravidez , Espanha
11.
Gen Pharmacol ; 20(2): 243-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2714621

RESUMO

1. Pentobarbital and verapamil produced concentration-dependent vasodilation in segments of middle cerebral artery of either control or exposed to experimental subarachnoid hemorrhage (SAH) cats precontracted with 5-hydroxytryptamine (5-HT, 10(-5) M) or K+ (75 mM), the potency to evoke relaxation being greater for verapamil than pentobarbital. 2. Pentobarbital (10(-4) M and 10(-3) M) or verapamil (10(-6) M) inhibited the contractions induced by 10(-5) M 5-HT or 75 mM K+ in both kinds of vessels. 3. Pentobarbital (10(-3) M) and verapamil (10(-6) M) reduced the concentration-dependent contractions induced by Ca2+ addition in control and SAH arteries previously exposed to Ca2+-free medium containing K+ or 5-HT. 4. All these vasodepressor effects of pentobarbital and verapamil were similar in control and SAH vessels, suggesting that the sensitivity of them to these agents is unaffected by SAH.


Assuntos
Artérias Cerebrais/efeitos dos fármacos , Pentobarbital/farmacologia , Hemorragia Subaracnóidea/fisiopatologia , Verapamil/farmacologia , Animais , Gatos , Artérias Cerebrais/fisiopatologia , Feminino , Masculino , Potássio/farmacologia
12.
Rev Cubana Estomatol ; 25(3): 81-5, 1988.
Artigo em Espanhol | MEDLINE | ID: mdl-3272440

RESUMO

An up-to-date review on dentigerous cysts is carried out and the fact that no report has been found in the medical literature on a similar case to that one of our patient is pointed out. The clinical picture, radiographic characteristics, diagnosis, treatment and prognosis of these cases are described. Peculiarity of our patient because of the amount of teeth contained in the cyst, as well as persistence of deciduous teeth, is outlined.


Assuntos
Cisto Dentígero , Adulto , Humanos , Masculino , Erupção Dentária , Dente Decíduo/anormalidades
13.
Rev Cubana Estomatol ; 25(3): 86-93, 1988.
Artigo em Espanhol | MEDLINE | ID: mdl-3272441

RESUMO

The case of a young man aged 18 years, attending to the Outpatient Service, Clinical and Surgical Teaching Hospital, Santa Clara, because of pathologic fracture in the anterior region of the jaw and history of hospitalization by pain and inflammation of mandibular gingiva with mobility of anterior teeth causing multiple extractions. The physical examination showed facial asymmetry by loss of normal chin configuration. Within investigations performed we had to rest on clinics, radiographical studies and anatomopathologic results. We think that the publication of this paper helps to enrich the scanty literature on this rare disease, which at international level is the tenth case involving the jaw and first in our country.


Assuntos
Doenças Mandibulares , Osteólise , Adolescente , Queixo/anormalidades , Humanos , Masculino , Fraturas Mandibulares/etiologia
14.
Rev. cuba. cir ; 27(2): 33-9, mar.-abr. 1988. tab
Artigo em Espanhol | CUMED | ID: cum-11824

RESUMO

Se revisan 100 historias clínicas de pacientes operados de tumores primarios de las glándulas parótidas. En esta revisión se encontraron 10 casos afectados del síndrome de Frey. Se describen la fisiopatología y la localización, y se da a conocer el tratamiento médico o quirúrgico que se puede utilizar en estos casos. Se destaca como elemento importante para detectar el síndrome de Frey, el seguimiento de los pacientes operados de tumores de las glándulas parótidas(AU)


Assuntos
Sudorese Gustativa
15.
Psychol Med ; 17(1): 227-41, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3495013

RESUMO

A two-stage mental illness survey of a random sample of persons aged 17 years and over from a rural community in Cantabria, Spain, is described. In the first stage newly qualified doctors and final year medical students interviewed 1223 respondents (583 males and 640 females) at their homes, using the General Health Questionnaire (GHQ-60) and other psychopathological and social questionnaires. In the second stage senior psychiatrists carried out an at-home interview on a sample composed of all those who in the first stage scored above the cut-off point on the GHQ, and of a similar number of persons selected at random from two independent batches of below-threshold scorers on the GHQ. Because of this design the prevalence figures have to be weighted in order to represent the whole first stage sample. Of the total population, 14.7% (8.1% of the men and 20.6% of the women) had psychiatric disorders as defined by the PSE-ID system. In males depression accounted for about twice as many cases as anxiety states, but in females there was a predominance of a combination of anxiety, phobic and obsessive conditions. Men presented a higher prevalence of disorders over the age of 35, with a peak around the age of forty, while in women the rise of prevalence was over the age of 45. There was, however, no significant association with marital status. Unemployment was related to mental illness in males but not in females, while the reverse was true of the type of work. In both sexes the presence of children under fourteen in the household was not related to a rise in prevalence. Women exhibited a high rate of mental illness in the low educational level and in the low social and religious integration groups, but in men a rise in prevalence was found in the low social status, low educational level and low social integration groups. Lastly, in both sexes the presence of physical illness was related to mental disorders.


Assuntos
Transtornos Mentais/epidemiologia , População Rural , Adulto , Fatores Etários , Estudos Transversais , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Testes Psicológicos , Transtornos Psicofisiológicos/epidemiologia , Fatores Sexuais , Ajustamento Social , Classe Social , Meio Social , Espanha
16.
Medicentro ; 2(1): 34-41, 1986. ilus
Artigo em Espanhol | CUMED | ID: cum-20523

RESUMO

Se informa sobre un paciente con una rarísima enfermedad conocida con el nombre de Osteolisis Masiva. Pretendemos con la publicación de este trabajo enriquecer la escasa bibliografía, que sobre esta enfermedad existe a nivel internacional, con la particularidad de ser el primer caso conocido en nuestro país y el séptimo a escala mundial, que involucra la mandíbula


Assuntos
Osteólise Essencial , Mandíbula
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