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1.
Nat Commun ; 10(1): 4062, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492855

RESUMO

The growth and wetting of water on two-dimensional(2D) materials are important to understand the development of 2D material based electronic, optoelectronic, and nanomechanical devices. Here, we visualize the liquefaction processes of water on the surface of graphene, MoS2 and black phosphorus (BP) via optical microscopy. We show that the shape of the water droplets forming on the surface of BP, which is anisotropic, is elliptical. In contrast, droplets are rounded when they form on the surface of graphene or MoS2, which do not possess orthometric anisotropy. Molecular simulations show that the anisotropic liquefaction process of water on the surface of BP is attributed to the different binding energies of H2O molecules on BP along the armchair and zigzag directions. The results not only reveal the anisotropic nature of water liquefaction on the BP surface but also provide a way for fast and nondestructive determination of the crystalline orientation of BP.

2.
Comput Methods Programs Biomed ; 178: 163-173, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416545

RESUMO

BACKGROUND AND OBJECTIVE: Wheezing is a common symptom of patients caused by asthma and chronic obstructive pulmonary diseases. Wheezing detection identifies wheezing lung sounds and helps physicians in diagnosis, monitoring, and treatment of pulmonary diseases. Different from the traditional way to detect wheezing sounds using digital image process methods, automatic wheezing detection uses computerized tools or algorithms to objectively and accurately assess and evaluate lung sounds. We propose an innovative machine learning-based approach for wheezing detection. The phases of the respiratory sounds are separated automatically and the wheezing features are extracted accordingly to improve the classification accuracy. METHODS: To enhance the features of wheezing for classification, the Adaptive Multi-Level In-Exhale Segmentation (AMIE_SEG) is proposed to automatically and precisely segment the respiratory sounds into inspiratory and expiratory phases. Furthermore, the Enhanced Generalized S-Transform (EGST) is proposed to extract the wheezing features. The highlighted features of wheezing improve the accuracy of wheezing detection with machine learning-based classifiers. RESULTS: To evaluate the novelty and superiority of the proposed AMIE_SEG and EGST for wheezing detection, we employ three machine learning-based classifiers, Support Vector Machine (SVM), Extreme Learning Machine (ELM) and K-Nearest Neighbor (KNN), with public datasets at segment level and record level respectively. According to the experimental results, the proposed method performs the best using the KNN classifier at segment level, with the measured accuracy, sensitivity, specificity as 98.62%, 95.9% and 99.3% in average respectively. On the other aspect, at record level, the three classifiers perform excellent, with the accuracy, sensitivity, specificity up to 99.52%, 100% and 99.27% respectively. We validate the method with public respiratory sounds dataset. CONCLUSION: The comparison results indicate the very good performance of the proposed methods for long-term wheezing monitoring and telemedicine.

3.
BMC Ophthalmol ; 19(1): 161, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349817

RESUMO

BACKGROUND: Persistent hyperplastic primary vitreous (PHPV) is a rare congenital developmental ocular disorder caused by incomplete regression of the embryonic hyaloid vasculature. Here we report a case of nonsurgical unilateral anterior PHPV that was managed by amblyopia treatment and resulted in an improvement of visual acuity and regression of the fetal vasculature. CASE PRESENTATION: A three-year-old girl was diagnosed with unilateral anterior PHPV in the left eye, manifested with posterior pole cataract, posterior capsule opacification, tunica vasculosa lentis, and a floating hyaloid artery connected to the retrolental mass. The plaque was not large enough to fill the pupil, and conservative management along with amblyopia treatment was conducted. Nineteen months later, the visual acuity in the affected eye improved from 20/100 to 20/50 with correction, and the fetal vasculature regressed gradually and finally into a nonperfusion ghost vessel. CONCLUSIONS: In PHPV-affected children, regression of the fetal vasculature may be observed, and conservative management and amblyopia treatment may be helpful for visual improvement.


Assuntos
Tratamento Conservador/métodos , Vítreo Primário Hiperplásico Persistente/diagnóstico , Recuperação de Função Fisiológica , Acuidade Visual/fisiologia , Corpo Vítreo/anormalidades , Pré-Escolar , Progressão da Doença , Óculos , Feminino , Seguimentos , Humanos , Vítreo Primário Hiperplásico Persistente/fisiopatologia , Vítreo Primário Hiperplásico Persistente/terapia , Privação Sensorial , Corpo Vítreo/diagnóstico por imagem
4.
Small ; 15(23): e1900902, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016874

RESUMO

Non-layered tellurium (Te) is a promising material for applications in transistor and optoelectronic devices for its advantages in excellent intrinsic electronic and optoelectronic properties. However, the poor photodetection performance and relatively uncertain stability of tellurene under ambient conditions greatly limit the practical applications. In order to improve the performance of tellurene-based materials, Te@Se roll-to-roll nanotubes with different selenium (Se) contents synthesized by epitaxial growth of Se on Te nanotubes are, for the first time, employed to fabricate working electrodes for photoelectrochemical (PEC)-type broadband photodetection. They exhibit not only a preferably enhanced capacity for self-powered broadband photodetection but also significantly improved photocurrent density and stability in various aqueous environments (HCl, NaCl, and KOH solutions), compared to tellurene-based photodetectors. It is anticipated that the present work can open up new possibilities for high-performance tellurene-based optoelectronic devices.

5.
Sci Rep ; 9(1): 3137, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816322

RESUMO

Early detection of diabetic microvascular complications is of great significance for disease prognosis. This systematic review and meta-analysis aimed to investigate the correlation among diabetic microvascular complications which may indicate the importance of screening for other complications in the presence of one disorder. PubMed, Embase, and the Cochrane Library were searched and a total of 26 cross-sectional studies met our inclusion criteria. Diabetic retinopathy (DR) had a proven risk association with diabetic kidney disease (DKD) [odds ratio (OR): 4.64, 95% confidence interval (CI): 2.47-8.75, p < 0.01], while DKD also related to DR (OR: 2.37, 95% CI: 1.79-3.15, p < 0.01). In addition, DR was associated with diabetic neuropathy (DN) (OR: 2.22, 95% CI: 1.70-2.90, p < 0.01), and DN was related to DR (OR: 1.73, 95% CI: 1.19-2.51, p < 0.01). However, the risk correlation between DKD and DN was not definite. Therefore, regular screening for the other two microvascular complications in the case of one complication makes sense, especially for patients with DR. The secondary results presented some physical conditions and comorbidities which were correlated with these three complications and thus should be paid more attention.

6.
J Med Chem ; 62(7): 3228-3250, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30893553

RESUMO

Bruton's tyrosine kinase (BTK), a non-receptor tyrosine kinase, is a member of the Tec family of kinases and is essential for B cell receptor (BCR) mediated signaling. BTK also plays a critical role in the downstream signaling pathways for the Fcγ receptor in monocytes, the Fcε receptor in granulocytes, and the RANK receptor in osteoclasts. As a result, pharmacological inhibition of BTK is anticipated to provide an effective strategy for the clinical treatment of autoimmune diseases such as rheumatoid arthritis and lupus. This article will outline the evolution of our strategy to identify a covalent, irreversible inhibitor of BTK that has the intrinsic potency, selectivity, and pharmacokinetic properties necessary to provide a rapid rate of inactivation systemically following a very low dose. With excellent in vivo efficacy and a very desirable tolerability profile, 5a (branebrutinib, BMS-986195) has advanced into clinical studies.

7.
Acta Diabetol ; 56(8): 823-837, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30900027

RESUMO

AIMS: Diabetic retinopathy (DR) is an important microvascular complication of diabetes mellitus (DM) and a leading cause of visual impairment and blindness among people of working age. Physical activity (PA) or exercise is critical and beneficial for DM patients, whereas studies evaluating the relationship between PA and DR have yielded inconsistent and inconclusive results. The American Diabetes Association's "Standards of Medical Care in Diabetes" has also pointed out the indeterminate roles of PA in DR prevention. The purpose of this systematic review and meta-analysis was to explore the association between PA and DR risk. METHODS: Medline (accessed by PubMed), EmBase, and Cochrane Library were systematically searched for studies up to June 2018, and the reference lists of the published articles were searched manually. The association between PA and DR risk was assessed using random-effect meta-analysis. RESULTS: Twenty-two studies were included in this meta-analysis. PA was found to have a protective association with DR [risk ratio (RR) = 0.94, 95% confidence interval (95% CI) 0.90-0.98, p = 0.005] in diabetic patients, and the impact was more pronounced on vision-threatening DR (RR = 0.89, 95% CI 0.80-0.98, p = 0.02). Sedentary behavior could increase the risk of DR (RR = 1.18, 95% CI 1.01-1.37, p = 0.04). Moderate-intensity PA was likely to have a slight protective effect (RR = 0.76, 95% CI 0.58-1.00, p = 0.05). CONCLUSION: PA is associated with lower DR risk, and more studies should focus on the causality between them.


Assuntos
Retinopatia Diabética/epidemiologia , Exercício , Humanos , Comportamento Sedentário
8.
Adv Mater ; 31(14): e1807981, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30730064

RESUMO

Graphdiyne is a new carbon allotrope comprising sp- and sp2 -hybridized carbon atoms arranged in a 2D layered structure. In this contribution, 2D graphdiyne is demonstrated to exhibit a strong light-matter interaction with high stability to achieve a broadband Kerr nonlinear optical response, which is useful for nonreciprocal light propagation in passive photonic diodes. Furthermore, advantage of the unique Kerr nonlinearity of 2D graphdiyne is taken and a nonreciprocal light propagation device is proposed based on the novel similarity comparison method. Graphdiyne has demonstrated a large nonlinear refractive index in the order of ≈10-5 cm2 W-1 , comparing favorably to that of graphene. Based on the strong Kerr nonlinearity of 2D graphdiyne, a nonlinear photonic diode that breaks time-reversal symmetry is demonstrated to realize the unidirectional excitation of Kerr nonlinearity, which can be regarded as a significant demonstration of a graphdiyne-based prototypical application in nonlinear photonics and might suggest an important step toward versatile graphdiyne-based advanced passive photonics devices in the future.

9.
Nanoscale ; 11(6): 2637-2643, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30698602

RESUMO

In this work, 0-dimensional (0D) CsPbBr3 QDs were integrated with 2D bismuthene having ultrafast carrier mobility, to obtain a 0D/2D nanohybrid. Moreover, an excellent charge transfer efficiency (0.53) and an appreciable quenching constant of 2.3 × 105 M-1 were observed. Tuning the ratio of bismuthene in the Bi/perovskite nanohybrid achieved the quantified control of charge transfer efficiency and quenching performance at the interface.

10.
ACS Appl Mater Interfaces ; 11(4): 4278-4287, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30623664

RESUMO

Owing to the attractive energy band properties, a black phosphorus (BP)-analogue semiconductor, germanium selenide (GeSe), shows a promising potential applied for optoelectronic devices. Herein, ultrathin GeSe nanosheets were systematically prepared via a facile liquid-phase exfoliation approach, with controllable nanoscale thickness. Different from BP, ultrathin GeSe nanosheets exhibit good stability under both liquid and ambient conditions. Besides, its ultrafast carrier dynamics was probed by transient absorption spectroscopy. We showed that the GeSe nanosheet-based photodetector exhibits excellent photoresponse behaviors ranging from ultraviolet (UV) to the visible regime, with high responsivity and low dark current. Furthermore, the detective ability of such a device can be effectively modulated by varying the applied bias potential, light intensity, and concentration of the electrolyte. Generally, our present contribution could not only supply fundamental knowledge of a GeSe nanosheet-based photoelectrochemical (PEC)-type device, but also offer guidance to extend other possible semiconductor materials in the application of the PEC-type photodetector.

11.
Medicine (Baltimore) ; 97(48): e13251, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30508911

RESUMO

BACKGROUND: Successful labor induction depends on the cervical status at the time of induction. Currently, both a Foley catheter and a dinoprostone insert are used for effective cervical ripening. This study compared the efficacy and safety of the intracervical Foley catheter and dinoprostone insert for cervical ripening to achieve successful labor induction. METHODS: PubMed, Embase, and the Cochrane Library were searched from January 2000 to February 2017 for relevant articles. Only published randomized, controlled trials comparing the dinoprostone insert with the Foley catheter were included. RESULTS: Eight trials including 1191 women who received the intracervical Foley catheter balloon and 1199 who received the dinoprostone insert were used for this study. There was no significant difference between the 2 groups regarding the induction-to-delivery (I-D) interval in a random effect model (mean difference, 0.71 hours; 95% confidence interval [CI], -2.50 to 3.91; P = .67). The highly significant heterogeneity (I = 97%) could be explained by the subgroup analysis of the type of Foley catheter and balloon volume. There was no significant difference between the 2 methods regarding the cesarean delivery rate (relative risk, 0.91; 95% CI, 0.78-1.07; P = .24), Apgar score, or side effects, including maternal infection rate, postpartum hemorrhage, and hyperstimulation. No obvious publication bias was found. CONCLUSIONS: According to the cesarean delivery rate, the intracervical Foley catheter balloon was as efficient as the dinoprostone insert. A moderate balloon volume (30 mL) and higher dose of dinoprostone (≥6 mg) were related to shorter I-D intervals. Additionally, there was no significant difference between the two methods regarding maternal or neonatal safety.

12.
Nanoscale ; 10(44): 20540-20547, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30402631

RESUMO

In recent years, black-phosphorus-analogue (BPA) two-dimensional (2D) materials have been explored to demonstrate promising optoelectronic performances and distinguished ambient stabilities, holding great promise in practical applications. Here, one new kind of BPA material, orthorhombic ß-PbO quantum dots (QDs), is successfully fabricated by a facile liquid phase exfoliation (LPE) technique. The as-prepared ß-PbO QDs show a homogeneous distribution of the lateral size (3.2 ± 0.9 nm) and thickness (2.5 ± 0.5 nm), corresponding to 4 ± 1 layers. The carrier dynamics of ß-PbO QDs was systematically investigated via a femtosecond resolution transient absorption approach in the visible wavelength regime and it was clarified that two decay components were resolved with a decay time of τ1 = 2.3 ± 0.3 ps and τ2 = 87.9 ± 6.0 ps, respectively, providing important insights into their potential applications in the field of ultrafast optics, nanomechanics and optoelectronics. As a proof-of-concept, ß-PbO QDs were, for the first time to our knowledge, fabricated as a working electrode in a photoelectrochemical (PEC)-typed photodetector that exhibits significantly high photocurrent density and excellent stability under ambient conditions.

13.
J Ophthalmol ; 2018: 1425707, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30425852

RESUMO

Purpose: Intravitreal antivascular endothelial growth factor (anti-VEGF) therapy has been widely used for the treatment of neovascularization (NV) secondary to age-related macular degeneration (AMD). This study aimed to compare the efficacy among different subtypes of neovascular age-related macular degeneration (nAMD). Methods: PubMed, Embase, and the Cochrane Library were searched for eligible studies. We performed meta-analysis using Review Manager 5.3 and Stata/SE 12.0. Results: A total of 24 studies met our inclusion criteria and were included in the systematic review. At 3 months, the mean logarithm of the minimum angle of resolution (logMAR) improvements were -0.09, -0.18, and -0.23 for type 1, 2, and 3, respectively, while the mean macular thickness (MT) changes were -104.83, -130.76, and -196.29 µm. At 12 months, the mean changes in Early Treatment of Diabetic Retinopathy Study (ETDRS) letters were 6.38, 8.12, and 9.37, while the MT decrease was 126.51, 126.52, and 139.85 µm, respectively. However, statistically significant difference was only found between type 1 and 3 in vision improvement, both in the short term (p=0.0002) and long term (p=0.01). Conclusions: The reactivity to VEGF inhibitors varied among different subtypes of nAMD. The efficacy of intravitreal anti-VEGF therapy in type 3 nAMD was statistically better than type 1 when considering vision improvement at 3 and 12 months. Thus, the lesion subtype is a predictor for the treatment outcome which can help guide prognosis.

14.
Artigo em Inglês | MEDLINE | ID: mdl-29994776

RESUMO

Speech is easily affected by different background noise in real environment to reduce the speech intelligibility, in particular, for hearing impaired listeners. In order to improve the above issue, several hearing aids have been developed to enhance the speech signal in noisy environment. Most of current hearing aids were designed to enhance the component of speech and suppress the component of noise. However, it is difficult to separate other speech sources. Adaptive signal enhancement (ASE) with the beamforming technique might improve the above issue. However, how to distinguish the location of the desired speaker effectively is still a difficult challenge for adaptive beamforming method. A novel concept of hearing aid was proposed in this study. Different from the beamforming-based hearing aids which use the cross-correlation-coefficient method to estimate time difference of arrival (TDOA), an image recognition technology was used to estimate the location of the desired speaker to obtain the more precise TDOA. An adaptive signal enhancement was also used to enhance the noisy speech sound. From the experimental results, the proposed system could provide a smaller absolute error of TDOA less than 1.25 10 ms, and a clear speech sound from the target speaker who the user wants to listen to.

15.
BMC Ophthalmol ; 18(1): 151, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29940965

RESUMO

BACKGROUND: To compare the abundance of vitreous proteins between the patients with proliferative diabetic retinopathy (PDR) and idiopathic macular hole (IMH). METHODS: In this study, we performed mass spectrometry-based label-free quantitative proteomics analysis of vitreous samples from type 2 diabetic patients with PDR (n = 9) and IMH subjects (n = 9) and identified the abundance of 610 proteins. RESULTS: Out of 610 proteins, 64 proteins (Group A) were unique to PDR patients, while 212 proteins (Group B) could be identified in IMH vitreous only. Among the other 334 proteins that could be detected in both PDR and IMH eyes, 62 proteins differed significantly (p < 0.05, fold change > 2), which included 52 proteins (Group C) and 10 proteins (Group D) over- and under-expressed in PDR vitreous compared with the control. All proteins in these four groups were counted as significant proteins in our study. CONCLUSIONS: We identified and quantified 610 proteins in total, which included 338 significant proteins in our study. Protein distribution analysis demonstrated a clear separation of protein expression in PDR and IMH. The protein function analysis illustrated that immunity and transport related proteins might be associated with PDR.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/metabolismo , Proteínas do Olho/metabolismo , Proteômica/métodos , Vitreorretinopatia Proliferativa/metabolismo , Corpo Vítreo/química , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos , Espectrometria de Massas , Estudos Prospectivos , Vitreorretinopatia Proliferativa/diagnóstico , Vitreorretinopatia Proliferativa/etiologia , Corpo Vítreo/patologia
16.
J Healthc Eng ; 2018: 9050812, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854370

RESUMO

A systematical evaluation work was performed on ten widely used and high-efficient QRS detection algorithms in this study, aiming at verifying their performances and usefulness in different application situations. Four experiments were carried on six internationally recognized databases. Firstly, in the test of high-quality ECG database versus low-quality ECG database, for high signal quality database, all ten QRS detection algorithms had very high detection accuracy (F1 >99%), whereas the F1 results decrease significantly for the poor signal-quality ECG signals (all <80%). Secondly, in the test of normal ECG database versus arrhythmic ECG database, all ten QRS detection algorithms had good F1 results for these two databases (all >95% except RS slope algorithm with 94.24% on normal ECG database and 94.44% on arrhythmia database). Thirdly, for the paced rhythm ECG database, all ten algorithms were immune to the paced beats (>94%) except the RS slope method, which only output a low F1 result of 78.99%. At last, the detection accuracies had obvious decreases when dealing with the dynamic telehealth ECG signals (all <80%) except OKB algorithm with 80.43%. Furthermore, the time costs from analyzing a 10 s ECG segment were given as the quantitative index of the computational complexity. All ten algorithms had high numerical efficiency (all <4 ms) except RS slope (94.07 ms) and sixth power algorithms (8.25 ms). And OKB algorithm had the highest numerical efficiency (1.54 ms).

17.
ACS Med Chem Lett ; 9(5): 472-477, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29795762

RESUMO

There is a significant unmet medical need for more efficacious and rapidly acting antidepressants. Toward this end, negative allosteric modulators of the N-methyl-d-aspartate receptor subtype GluN2B have demonstrated encouraging therapeutic potential. We report herein the discovery and preclinical profile of a water-soluble intravenous prodrug BMS-986163 (6) and its active parent molecule BMS-986169 (5), which demonstrated high binding affinity for the GluN2B allosteric site (Ki = 4.0 nM) and selective inhibition of GluN2B receptor function (IC50 = 24 nM) in cells. The conversion of prodrug 6 to parent 5 was rapid in vitro and in vivo across preclinical species. After intravenous administration, compounds 5 and 6 have exhibited robust levels of ex vivo GluN2B target engagement in rodents and antidepressant-like activity in mice. No significant off-target activity was observed for 5, 6, or the major circulating metabolites met-1 and met-2. The prodrug BMS-986163 (6) has demonstrated an acceptable safety and toxicology profile and was selected as a preclinical candidate for further evaluation in major depressive disorder.

18.
Angew Chem Int Ed Engl ; 57(29): 8901-8905, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-29684238

RESUMO

The sluggish sodium reaction kinetics, unstable Sn/Na2 O interface, and large volume expansion are major obstacles that impede practical applications of SnO2 -based electrodes for sodium-ion batteries (SIBs). Herein, we report the crafting of homogeneously confined oxygen-vacancy-containing SnO2-x nanoparticles with well-defined void space in porous carbon nanofibers (denoted SnO2-x /C composites) that address the issues noted above for advanced SIBs. Notably, SnO2-x /C composites can be readily exploited as the working electrode, without need for binders and conductive additives. In contrast to past work, SnO2-x /C composites-based SIBs show remarkable electrochemical performance, offering high reversible capacity, ultralong cyclic stability, and excellent rate capability. A discharge capacity of 565 mAh g-1 at 1 A g-1 is retained after 2000 cycles.

19.
Nanotechnology ; 29(23): 235201, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29543188

RESUMO

Two dimensional Bi nanosheets have been employed to fabricate electrodes for broadband photo-detection. A series of characterization techniques including scanning electron microscopy and high-resolution transmission electron microscopy have verified that Bi nanosheets with intact lamellar structure have been obtained after facile liquid phase exfoliation. In the meanwhile, UV-vis and Raman spectra are also carried out and the inherent optical and physical properties of Bi nanosheets are confirmed. Inherited from the topological characteristics of Bi bulk counterpart, the resultant Bi nanosheet-based photo-detector exhibits preferable photo-response activity as well as environmental robustness. We then evaluate the photo-electrochemical (PEC) performance of the photodetector in 1 M NaOH and 0.5 M Na2SO4 electrolytes, and demonstrated that the as-prepared Bi nanosheets may possess a great potential as PEC-type photo-detector. Additional PEC measurements show that the current density of Bi nanosheets can reach up to 830 nA cm-2, while an enhanced responsivity (1.8 µA W-1) had been achieved. We anticipate that this contribution can provide feasibility towards the construction of high-performance elemental Bi nanosheets-based optoelectronic devices in the future.

20.
J Healthc Eng ; 2018: 2687389, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29599945

RESUMO

Energy efficiency is still the obstacle for long-term real-time wireless ECG monitoring. In this paper, a digital compressed sensing- (CS-) based single-spot Bluetooth ECG node is proposed to deal with the challenge in wireless ECG application. A periodic sleep/wake-up scheme and a CS-based compression algorithm are implemented in a node, which consists of ultra-low-power analog front-end, microcontroller, Bluetooth 4.0 communication module, and so forth. The efficiency improvement and the node's specifics are evidenced by the experiments using the ECG signals sampled by the proposed node under daily activities of lay, sit, stand, walk, and run. Under using sparse binary matrix (SBM), block sparse Bayesian learning (BSBL) method, and discrete cosine transform (DCT) basis, all ECG signals were essentially undistorted recovered with root-mean-square differences (PRDs) which are less than 6%. The proposed sleep/wake-up scheme and data compression can reduce the airtime over energy-hungry wireless links, the energy consumption of proposed node is 6.53 mJ, and the energy consumption of radio decreases 77.37%. Moreover, the energy consumption increase caused by CS code execution is negligible, which is 1.3% of the total energy consumption.

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