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1.
Sci Rep ; 14(1): 11337, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760402

RESUMO

Verifying the quality of a random number generator involves performing computationally intensive statistical tests on large data sets commonly in the range of gigabytes. Limitations on computing power can restrict an end-user's ability to perform such verification. There are also random number-based applications where an honest user needs to publicly demonstrate that the random bits they are using pass the statistical tests without the bits being revealed. Here, we report the implementation of an entanglement-based protocol that allows a third party to publicly perform statistical tests without compromising the privacy of the random bits.

2.
Opt Express ; 32(7): 11406-11418, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570989

RESUMO

We report a stable, low loss method for coupling light from silicon-on-insulator (SOI) photonic chips into optical fibers. The technique is realized using an on-chip tapered waveguide and a cleaved small core optical fiber. The on-chip taper is monolithic and does not require a patterned cladding, thus simplifying the chip fabrication process. The optical fiber segment is composed of a centimeter-long small core fiber (UHNA7) which is spliced to SMF-28 fiber with less than -0.1 dB loss. We observe an overall coupling loss of -0.64 dB with this design. The chip edge and fiber tip can be butt coupled without damaging the on-chip taper or fiber. Friction between the surfaces maintains alignment leading to an observation of ±0.1 dB coupling fluctuation during a ten-day continuous measurement without use of any adhesive. This technique minimizes the potential for generating Raman noise in the fiber, and has good stability compared to coupling strategies based on longer UHNA fibers or fragile lensed fibers. We also applied the edge coupler on a correlated photon pair source and observed a raw coincidence count rate of 1.21 million cps and raw heralding efficiency of 21.3%. We achieved an auto correlation function g H(2)(0) as low as 0.0004 at the low pump power regime.

3.
Opt Express ; 30(9): 15607-15615, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473277

RESUMO

Nonlocal dispersion compensation between broadband nondegenerate photon pairs propagated over fiber corresponding to the ITU-T G.652D telecommunications standard was studied extensively via fine-grained measurements of the temporal correlation between them. We demonstrated near-ideal levels of nonlocal dispersion compensation by adjusting the propagation distance of the photon pairs to preserve photon timing correlations close to the effective instrument resolution of our detection apparatus (41.0±0.1ps). Experimental data indicates that this degree of compensation can be achieved with relatively large fiber increments (1km), compatible with real-world deployment. Ultimately, photon timing correlations were preserved down to 51ps±21ps over two multi-segmented 10km spans of deployed metropolitan fiber.

4.
BMJ Case Rep ; 13(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31900293

RESUMO

Tuberculosis is on the rise again. It brings with it potential for neurological involvement both as a direct infection and as a parainfectious process. Accordingly we report the development of neurological problems affecting a 48-year-old patient's vision and sensation while being treated for active tuberculosis. At its nadir her vision deteriorated to nil perception of light and she had a sensory level to T10. Neuromyelitis optica spectrum disorder was diagnosed. We discuss our management strategy with neuromodulation in the context of active tuberculosis infection.


Assuntos
Neuromielite Óptica/etiologia , Neuromielite Óptica/terapia , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/terapia , Diagnóstico Diferencial , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuromielite Óptica/diagnóstico por imagem , Troca Plasmática , Prednisolona/uso terapêutico , Rituximab/uso terapêutico , Tuberculose Pulmonar/diagnóstico por imagem
5.
Entropy (Basel) ; 21(4)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33267101

RESUMO

An application of quantum communications is the transmission of qubits to create shared symmetric encryption keys in a process called quantum key distribution (QKD). Contrary to public-private key encryption, symmetric encryption is considered safe from (quantum) computing attacks, i.e. it provides forward security and is thus attractive for secure communications. In this paper we argue that for free-space quantum communications, especially with satellites, if one assumes that man-in-the-middle attacks can be detected by classical channel monitoring techniques, simplified quantum communications protocols and hardware systems can be implemented that offer improved key rates. We term these protocols photon key distribution (PKD) to differentiate them from the standard QKD protocols. We identify three types of photon sources and calculate asymptotic secret key rates for PKD protocols and compare them to their QKD counterparts. PKD protocols use only one measurement basis which we show roughly doubles the key rates. Furthermore, with the relaxed security assumptions one can establish keys at very high losses, in contrast to QKD where at the same losses privacy amplification would make key generation impossible.

6.
Hum Pathol ; 43(3): 333-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21835432

RESUMO

Sarcoidal reactions occurring in regional lymph nodes of patients with non-small cell lung carcinoma appear to be limited to patients with stage I disease. The prognostic significance of this remains unknown. Such reactions are thought to represent a cell-mediated antitumor response and have been associated with improved outcomes in other solid organ malignancies. We performed a retrospective chart review of all patients undergoing lobectomy with curative intent for non-small cell lung carcinoma. Eligible cases were selected based on pathologic reports, with matched controls then drawn from the same surgical cohort. One hundred fifty-seven patients underwent lobectomy and lymph node dissection. Eight patients with sarcoidal granulomas present in regional lymph nodes were identified as cases and matched to 16 control subjects. All subjects were staged pN0. Disease recurrence was noted in no case subjects but in 7 (44%) of control subjects (P = .044, χ(2) = 4.051). The presence of sarcoidal reactions within regional lymph nodes of patients with non-small cell lung carcinoma predicts a lower rate of disease recurrence after definitive surgical resection. The exact mechanism by which antitumor immunity is achieved remains to be elucidated.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Sarcoidose/patologia , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Idoso , Austrália/epidemiologia , Carcinoma de Células Grandes/mortalidade , Carcinoma de Células Grandes/cirurgia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Estudos de Casos e Controles , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida
7.
J Clin Forensic Med ; 11(6): 285-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15522636

RESUMO

AIMS: To record the concentration of morphine in post-mortem blood samples from fatalities arising directly from illicit drug abuse in Grampian, Scotland and to explore whether there is any difference in the morphine levels with co-existent drugs especially alcohol and benzodiazepines. METHODS: Drug-related deaths that had positive blood toxicology for morphine from the beginning of January 1995 until the end of December 2001 were identified from the database of toxicological data held in the Department of Clinical Biochemistry, Aberdeen Royal Infirmary, and the data analysed in conjunction with the information in the files of the Forensic Medicine Unit, University of Aberdeen. RESULTS: One hundred and twenty-six cases were identified and consisted of 106 males and 20 females with an age range 17-51 (Median 26 years). Morphine was the single isolate in only 21 cases giving a median blood free morphine (BFM) of 0.19 mg/L. When morphine and benzodiazepines were the primary isolates [Formula: see text] the median BFM was 0.37 mg/L, and when morphine was in combination with alcohol [Formula: see text] the median BFM was 0.18 mg/L. Statistical significance was noted between these groups ( [Formula: see text] ). The remaining 59 cases had morphine combined with other drugs. CONCLUSIONS: In the studied cases, the concentrations of BFM were statistically higher when morphine was only isolated in conjunction with benzodiazepines than when combined only with alcohol. These results may be multi-factorial; user error while under drug influence, the individuals drug tolerance, or related to the pharmacokinetics of morphine and its interactions with alcohol and benzodiazepines. Our understanding of the interactions of these substances appears to be far from clear.


Assuntos
Benzodiazepinas , Morfina , Benzodiazepinas/sangue , Etanol/sangue , Toxicologia Forense , Humanos , Drogas Ilícitas , Morfina/sangue , Entorpecentes/sangue
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