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1.
J Clin Sleep Med ; 20(4): 545-553, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561941

RESUMO

STUDY OBJECTIVES: Previous studies have highlighted the importance of sleep patterns for human health. This study aimed to investigate the association of sleep timing with all-cause and cardiovascular disease mortality. METHODS: Participants were screened from two cohort studies: the Sleep Heart Health Study (SHHS; n = 4,824) and the Osteoporotic Fractures in Men Study (n = 2,658). Sleep timing, including bedtime and wake-up time, was obtained from sleep habit questionnaires at baseline. The sleep midpoint was defined as the halfway point between the bedtime and wake-up time. Restricted cubic splines and Cox proportional hazards regression analyses were used to examine the association between sleep timing and mortality. RESULTS: We observed a U-shaped association between bedtime and all-cause mortality in both the SHHS and Osteoporotic Fractures in Men Study groups. Specifically, bedtime at 11:00 pm and waking up at 7:00 am was the nadir for all-cause and cardiovascular disease mortality risks. Individuals with late bedtime (> 12:00 am) had an increased risk of all-cause mortality in SHHS (hazard ratio 1.53, 95% confidence interval 1.28-1.84) and Osteoporotic Fractures in Men Study (hazard ratio 1.27, 95% confidence interval 1.01-1.58). In the SHHS, late wake-up time (> 8:00 am) was associated with increased all-cause mortality (hazard ratio 1.39, 95% confidence interval 1.13-1.72). No significant association was found between wake-up time and cardiovascular disease mortality. Delaying sleep midpoint (> 4:00 am) was also significantly associated with all-cause mortality in the SHHS and Osteoporotic Fractures in Men Study. CONCLUSIONS: Sleep timing is associated with all-cause and cardiovascular disease mortality. Our findings highlight the importance of appropriate sleep timing in reducing mortality risk. CITATION: Ma M, Fan Y, Peng Y, et al. Association of sleep timing with all-cause and cardiovascular mortality: the Sleep Heart Health Study and the Osteoporotic Fractures in Men Study. J Clin Sleep Med. 2024;20(4):545-553.


Assuntos
Doenças Cardiovasculares , Fraturas por Osteoporose , Masculino , Humanos , Doenças Cardiovasculares/complicações , Sono , Polissonografia , Estudos de Coortes
2.
Vis Comput ; 39(3): 1137-1148, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35125577

RESUMO

This paper focuses on the instance segmentation task. The purpose of instance segmentation is to jointly detect, classify and segment individual instances in images, so it is used to solve a large number of industrial tasks such as novel coronavirus diagnosis and autonomous driving. However, it is not easy for instance models to achieve good results in terms of both efficiency of prediction classes and segmentation results of instance edges. We propose a single-stage instance segmentation model EEMask (edge-enhanced mask), which generates grid ROIs (regions of interest) instead of proposal boxes. EEMask divides the image uniformly according to the grid and then calculates the relevance between the grids based on the distance and grayscale values. Finally, EEMask uses the grid relevance to generate grid ROIs and grid classes. In addition, we design an edge-enhanced layer, which enhances the model's ability to perceive instance edges by increasing the number of channels with higher contrast at the instance edges. There is not any additional convolutional layer overhead, so the whole process is efficient. We evaluate EEMask on a public benchmark. On average, EEMask is 17.8% faster than BlendMask with the same training schedule. EEMask achieves a mask AP score of 39.9 on the MS COCO dataset, which outperforms Mask RCNN by 7.5% and BlendMask by 3.9%.

3.
Tuberculosis (Edinb) ; 137: 102270, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36265370

RESUMO

Tuberculosis (TB) is recognized as a highly infectious disease worldwide, and Bacille Calmette-Guerin (BCG) remains the only TB vaccine licensed for clinical use. As there is little evidence that BCG is effective in adults, there is an urgent need for a safe and effective vaccine to control TB in adults. In this study, we tested the immunomodulatory efficiency of the fusion protein AR2. whole blood IFN-γ release assay (WBIA) was used to detect antigen specificity. The immunogenicity of the vaccine was tested in C57BL/6 mice, and confirmed by enzyme-linked immunosorbent assay (ELISA), flow cytometry, and qRT-PCR. The fusion protein AR2 was successfully constructed and expressed. The level of IFN-γ in the peripheral blood of subjects stimulated by AR2 was significantly higher than in those induced by all subcomponent proteins. AR2-specific IgG and the Th1 cytokines IFN-γ, TNF-α, and iNOS were significantly increased in the group treated with the fusion protein and compound adjuvant (AR2+DMC). Likewise, the number of IFN-γ+ CD4+, IFN-γ+CD8+, and IL-4+ CD8+ T lymphocytes increased significantly. The combination of the fusion protein and the compound adjuvant (AR2+DMC) may be a suitable candidate for an enhanced TB vaccine. This study provides theoretical and experimental support for future research to enhance the effectiveness of TB vaccines and provides an experimental basis for evaluating the influence of different adjuvants on vaccine efficacy.


Assuntos
Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Tuberculose , Camundongos , Animais , Vacina BCG , Antígenos de Bactérias , Linfócitos T CD4-Positivos , Camundongos Endogâmicos C57BL , Adjuvantes Imunológicos
4.
Eur J Clin Microbiol Infect Dis ; 41(7): 1039-1049, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35612766

RESUMO

The dormancy survival regulator (DosR) antigens upgraded during latency and resuscitation-promoting factors (Rpfs) expressed over the reactivation from dormant Mycobacterium tuberculosis (M. tuberculosis) could be used to diagnose tuberculosis (TB) at different stages. We performed a retrospective cohort study based on four groups, including healthy controls (HCs), active tuberculosis infections (ATBs), latent tuberculosis infections (LTBIs), and relapse tuberculosis infections (RTBs) enrolled between November 2020 and June 2021. Compared to the fusion protein E6-C10, combined with early secreted antigenic target 6 kDa (ESAT-6) and culture filtrate of 10 kDa (CFP-10), the DosR- or Rpf-encoded antigens could not elicit significant IFN-γ concentration for the diagnosis of ATB. Of note, the DosR antigens produce significantly more antigen-specific IFN-γ in LTBIs than Rpfs, and the levels of antigen-specific IFN-γ elicited in RTBs stimulated by Rpfs were higher than the DosR antigens. Among the DosR antigens, Rv2003c was the most immunogenic in diagnosing LTBIs, followed by Rv2007c and Rv2005c. As far as Rpfs are concerned, Rv0867c was the best antigen to identify RTBs, followed by Rv2389c and Rv1009. Both Rv2450c and Rv1884c showed relatively limited IFN-γ concentration in RTBs. Besides, the selected DosR antigens and Rpfs showed ideal specificity and inadequate sensitivity, which could have been enhanced by the fusion antigens prepared by the DosR antigens or Rpfs, respectively. The results of this study can provide more accurate detection methods for LTBIs and RTBs and could be used for screening the dormant M. tuberculosis throughout reactivation.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Antígenos de Bactérias , Proteínas de Bactérias , Humanos , Tuberculose Latente/diagnóstico , Tuberculose Latente/microbiologia , Recidiva , Estudos Retrospectivos , Tuberculose/epidemiologia
5.
Nanomaterials (Basel) ; 11(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34361196

RESUMO

Due to the high field enhancement factor and photon-absorption efficiency, carbon nanotubes (CNTs) have been widely used in optically induced field-emission as a cathode. Here, we report vertical carbon nanotube arrays (VCNTAs) that performed as high-density electron sources. A combination of high applied electric field and laser illumination made it possible to modulate the emission with laser pulses. When the bias electric field and laser power density increased, the emission process is sensitive to a power law of the laser intensity, which supports the emission mechanism of optically induced field emission followed by over-the-barrier emission. Furthermore, we determine a polarization dependence that exhibits a cosine behavior, which verifies the high possibility of optically induced field emission.

6.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(2): 232-239, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32391670

RESUMO

Acute respiratory failure due to acute hypoxemia is the major manifestation in severe coronavirus disease 2019 (COVID-19). Rational and effective respiratory support is crucial in the management of COVID-19 patients. High-flow nasal cannula (HFNC) has been utilized widely due to its superiority over other non-invasive respiratory support techniques. To avoid HFNC failure and intubation delay, the key issues are proper patients, timely application and improving compliance. It should be noted that elder patients are vulnerable for failed HFNC. We applied HFNC for oxygen therapy in severe and critical ill COVID-19 patients and summarized the following experiences. Firstly, to select the proper size of nasal catheter, to locate it at suitable place, and to confirm the nose and the upper respiratory airway unobstructed. Secondly, an initial ow of 60 L/min and 37℃ should be given immediately for patients with obvious respiratory distress or weak cough ability; otherwise, low-level support should be given first and the level gradually increased. Thirdly, to avoid hypoxia or hypoxemia, the treatment goal of HFNC should be maintained the oxygen saturation (SpO2) above 95% for patients without chronic pulmonary disease. Finally, patients should wear a surgical mask during HFNC treatment to reduce the risk of virus transmission through droplets or aerosols.


Assuntos
Infecções por Coronavirus/terapia , Oxigênio , Pneumonia Viral/terapia , Idoso , Betacoronavirus/isolamento & purificação , COVID-19 , Cânula , Humanos , Oxigênio/administração & dosagem , Pandemias , SARS-CoV-2
7.
Nanotechnology ; 28(27): 275202, 2017 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-28531089

RESUMO

The heterojunction between metal and silicon (Si) is an attractive route to extend the response of Si-based photodiodes into the near-infrared (NIR) region, so-called Schottky barrier diodes. Photons absorbed into a metallic nanostructure excite the surface plasmon resonances (SPRs), which can be damped non-radiatively through the creation of hot electrons. Unfortunately, the quantum efficiency of hot electron detectors remains low due to low optical absorption and poor electron injection efficiency. In this study, we propose an efficient and low-cost plasmonic hot electron NIR photodetector based on a Au nanoparticle (Au NP)-decorated Si pyramid Schottky junction. The large-area and lithography-free photodetector is realized by using an anisotropic chemical wet etching and rapid thermal annealing (RTA) of a thin Au film. We experimentally demonstrate that these hot electron detectors have broad photoresponsivity spectra in the NIR region of 1200-1475 nm, with a low dark current on the order of 10-5 A cm-2. The observed responsivities enable these devices to be competitive with other reported Si-based NIR hot electron photodetectors using perfectly periodic nanostructures. The improved performance is attributed to the pyramid surface which can enhance light trapping and the localized electric field, and the nano-sized Au NPs which are beneficial for the tunneling of hot electrons. The simple and large-area preparation processes make them suitable for large-scale thermophotovoltaic cell and low-cost NIR detection applications.

8.
ACS Appl Mater Interfaces ; 8(5): 3295-300, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26795930

RESUMO

Suspended graphene (SG) membranes could enable strain-engineering of ballistic Dirac fermion transport and eliminate the extrinsic bulk disorder by annealing. When freely suspended without contact to any substrates, graphene could be considered as the ultimate two-dimensional (2D) morphology, leading to special field characteristics with the 2D geometrical effect and effectively utilized as an outstanding structure to explore the fundamental electronic or optoelectronic mechanism. In this paper, we report field emission characterization on an individual suspended few-layer graphene. A controllable wet transfer method is used to obtain the continuous and suspended graphene membrane on interdigitated gold electrodes. This suspended structure displays an overall field emission from the entirely surface, except for the variation in the emitting positions, acquiring a better enhancement than the exfoliated graphene on the conventional flat substrate. We also observe the transition process from space charge flow at low bias to the Fowler-Nordheim theory at high current emission regime. It could enable theoretical and experimental investigation of the typical electron emission properties of the 2D regime. Numerical simulations are also carried out to study the electrical properties of the suspended structure. Further improvement on the fabrication would realize low disorder, high quality, and large-scale suspended graphene devices.

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