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1.
Funct Integr Genomics ; 24(2): 56, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38472459

RESUMEN

Bladder cancer is a malignancy characterized by significant heterogeneity. RNA methylation has received an increasing amount of attention in recent years. RNA data were collected from the GEO database, and cell subsets were classified according to specific cell markers. Epithelial, immunological, and fibroblast cells were clustered individually to explore the tumor heterogeneity. To distinguish between malignant and benign cells, the InferCNV R package was employed. The monocle2 R package was used for pseudotime analysis. The Decouple R package was used for transcription factor analysis of each cell subgroup, and PROGENy was used to predict the activity of pathways related to tumors. The target lncRNA was screened for model construction. In addition, the qPCR experiment was used to detect the transcription level of lncRNA. Epithelial cells, fibroblasts, and T cells significantly differ in tumor and normal tissues. The lncRNAs related to m6A/m5C/m1A were intersected to construct the model. Finally, six model lncRNAs (PSMB8-AS1, THUMPD3-AS1, U47924.27, XXbac-B135H6.15, MIR99AHG, and C14orf132) were screened. High-risk individuals were shown to have a better prognosis. qPCR experiments showed that the model lncRNA was differentially expressed between normal and tumor cells. Immunotherapy will be more effective in treating individuals with lower risk than those with higher risk using 4 candidate drugs. The prognostic m6A/m5C/m1A-related lncRNA model was constructed for evaluating the clinical outcomes of bladder cancer patients and guiding clinical medication.


Asunto(s)
ARN Largo no Codificante , Neoplasias de la Vejiga Urinaria , Humanos , Pronóstico , Metilación de ARN , Inmunoterapia , Análisis de Secuencia de ARN
2.
Environ Toxicol ; 39(3): 1811-1821, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38073300

RESUMEN

BACKGROUND: Gastric cancer is the most common malignant tumour of the digestive system, yet there is a lack of reported prognostic biomarkers for STAD patients. METHODS: Transcriptomic expression data of STAD from GEO database, single cell sequencing data from OMIX gastric cancer database. Conservative molecular typing of gastric cancer was constructed using non-negative matrix factorization (NMF). The abundance of 28 immune cells in the tumour samples was assessed using ssGSEA. The R package "oncoPredict" was used to predict chemotherapy response. TIDE website for immunotherapy response prediction. Finally, single cell analysis was performed to clarify the specific type annotation of STAD cells and to analysis their spatial expression. RESULTS: Hypoxia-score demonstrated excellent prognostic discrimination in TCGA gastric cancer samples. Among multiple deconvolution-based algorithms for immune infiltration, Hypoxia-score presented a general immunosuppressive efficacy across multiple datasets, as evidenced by a broad negative correlation with immune cell infiltration. By the likelihood that each group may have specific drug sensitivity to multiple chemotherapeutic and targeted agents. Results showed that high-risk scoring patients were more sensitive to Staurosporine, Sabutoclax, and AZD8055, while low-risk patients were more sensitive to Bortezomib, Dactinomycin, Docetaxel, Daporinad, Sepantronium, and bromide. In the immunotherapy cohort, the Hypoxia-score presented the ability to discriminate for immunotherapy efficacy. The distribution of Hypoxia-score in single-cell descending space was calculated using AddModuleScore and was found to be distributed across the various cell types annotated in the single-cell analysis. It is suggested that various cells in the tumour microenvironment are involved in hypoxia gene set processes to varying degrees. CONCLUSION: The Hypoxia-score proves to be a valuable tool for assessing the prognosis of gastric cancer patients and guiding drug treatments, providing significant guidance for clinical diagnosis and treatment in the context of gastric cancer.


Asunto(s)
Adenocarcinoma , Neoplasias Gástricas , Humanos , Pronóstico , Docetaxel , Biomarcadores , Microambiente Tumoral
3.
Biochem Biophys Res Commun ; 624: 53-58, 2022 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-35932580

RESUMEN

KDM2A is a histone demethylase, which primarily catalyzes the demethylation of H3K36me2. Abnormal expression of KDM2A is observed in many types of cancers; however, the molecular events connected to KDM2A expression remain unclear. We report that KDM2A performs an oncogenic function in esophageal squamous cell carcinoma (ESCC) and is robustly expressed in ESCC cells. ShRNA-mediated knockdown of KDM2A resulted in a significant inhibition of the malignant phenotype of ESCC cell lines, whereas ectopic expression of KDM2A showed the opposite effect. We also analyzed the function of KDM2A using a CRISPR-CAS9 depletion system and subsequent rescue experiment, which also indicated a cancerous role of KDM2A. Interestingly, analysis of the gene expression network controlled by KDM2A using RNA-seq revealed an unexpected feature: KDM2A could induce expression of a set of well-documented oncogenic genes, including IL6 and LAT2, while simultaneously suppressing another set of oncogenes, including MAT2A and HMGCS1. Targeted inhibition of the upregulated oncogene in the KDM2A-depleted cells led to a synergistic suppressive effect on the malignant phenotype of ESCC cells. Our results revealed the dual role of KDM2A in ESCC cells, which may have therapeutic implications.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Proteínas F-Box , Carcinogénesis/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/genética , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Histona Demetilasas con Dominio de Jumonji/metabolismo , Metionina Adenosiltransferasa/metabolismo
4.
Small ; 18(37): e2200796, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35961951

RESUMEN

The core-void@shell architecture shows great advantages in enhancing cycling stability and high-rate performance of Si-based anodes. However, it is usually synthesized by template methods which are complex and environmentally unfriendly and would lead to low-efficiency charge and mass exchange because of the single-point van der Waals contact between the Si core and the shell. Here, a facile and benign one-step method to synthesize multi-Si-void@SiO2 structure, where abundant void spaces exist between multiple Si cores that are multi-point attached to a SiO2 shell through strong chemical bonding, is reported. The corresponding electrode exhibits highly stable cycling stability and excellent electrochemical performance. After 200 cycles at a current density of 0.1 A g-1 and then another 200 cycles at 1.2 A g-1 , the electrode outputs a specific capacity of 1440 mAh g-1 . Even at 2.0 A g-1 , it outputs a specific capacity as high as 1182 mAh g-1 . Such an anode can match almost all the cathode materials presently used in lithium-ion batteries. These results demonstrate the multi-Si-void@SiO2 as a promising anode to be used in future commercial lithium-ion batteries of high energy density and high power density.

5.
Nanotechnology ; 32(14): 145402, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33333500

RESUMEN

Tin/carbon (Sn/C) nanocomposite is considered as a promising anode material for high-performance Li-ion batteries (LIBs). However, since the carbon matrix is always derived from high-temperature carbonization of polymers and Sn has a low melting point (232 °C), the Sn nanoparticles in the Sn/C tend to be heavily aggregated during the carbonization process. It is thus challenging to synthesize well-dispersed Sn nanoparticles in a carbon matrix. Here, we report a facile templating method to encapsulate uniform well-dispersed Sn nanoparticles in amorphous carbon tube (Sn@aCT). The electrode fabricated with the hierarchical Sn@aCT exhibits excellent cycle performance. A stable specific capacity of 870 mAh g-1 after 350 cycles and a Li-ion diffusion coefficient as high as [Formula: see text] are obtained. Meanwhile, the intermediate structure of SnO2@aCT and a carbon-coated Sn yolk-shell nanostructure (Sn@C-YS) are investigated for comparison. The results further manifest the advantage of the architecture of the Sn@aCT. Our strategy provides a feasible way to optimize Sn/C nanocomposite as a high-performance anode material for LIBs.

6.
Nanotechnology ; 33(2)2021 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-34614484

RESUMEN

In nanocomposite electrodes, besides the synergistic effect that takes advantage of the merits of each component, phase interfaces between the components would contribute significantly to the overall electrochemical properties. However, the knowledge of such effects is far from being well developed up to now. The present work aims at a mechanistic understanding of the phase interface effect in C@TiO2core-shell nanocomposite anode which is both scientifically and industrially important. Firstly, amorphous C, anatase TiO2and C@anatse-TiO2electrodes are compared. The C@anatase-TiO2shows an obvious higher specific capacity (316.5 mAh g-1at a current density of 37 mA g-1after 100 cycles) and Li-ion diffusion coefficient (4.0 × 10-14cm2s-1) than the amorphous C (178 mAh g-1and 2.9 × 10-15cm2s-1) and anatase TiO2(120 mAh g-1and 1.6 × 10-15cm2s-1) owing to the C/TiO2phase interface effect. Then, C@anatase/rutile-TiO2is obtained by a heat treatment of the C@anatase-TiO2. Due to an anatase-to-rutile phase transformation and diffusion of C along the anatase/rutile phase interface, additional abundant C/TiO2phase interfaces are created. This endows the C@anatase/rutile-TiO2with further boosted specific capacity (409.4 mAh g-1at 37 mA g-1after 100 cycles) and Li-ion diffusion coefficient (3.2 × 10-13cm2s-1), and excellent rate capability (368.6 mAh g-1at 444 mA g-1). These greatly enhanced electrochemical properties explicitly reveal phase interface engineering as a feasible way to boost the electrochemical performance of nanocomposite anodes for Li-ion batteries.

8.
Inorg Chem ; 55(16): 7988-96, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27482720

RESUMEN

We combine nonequivalent substitution and charge-induced emitter-migration approaches and design an efficient method to optionally tune the spectral and duration properties of NaCa2GeO4F:Mn(2+) phosphor. A series of representative codopants have been investigated in detail and classified into two categories: RA (RA = Li(+), Al(3+), N(3-), Ga(3+), B(3+)) and RB (RB = Mg(2+), F(-), Bi(3+), Zn(2+), Cd(2+), Sc(3+), Tm(3+)). Results reveal that the nonequivalent substitution of RA codopants would induce foreign negative defects and stabilize Mn(2+) emitters at octahedral Na/Ca sites for red emission. In constrast, the RB codopants would generate foreign positive defects and make Mn(2+) emitters migrate to tetrahedral Ge(4+) sites for green-yellow emission. At the same time, the RA codopants are in favor of the generation of intrinsic positive traps with shallow trap depth and thus efficiently improve the duration properties of phosphors. On the basis of the experimental results, a possible nonequivalent substitution and charge-induced emitter-migration model has been proposed, and we can optionally tune the spectral (568 ↔ 627 nm) and the duration (minutes to more than 6 h) properties according to this model.

9.
Sensors (Basel) ; 16(10)2016 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-27669258

RESUMEN

Wireless Body Area Network (WBAN) applications have grown immensely in the past few years. However, security and privacy of the user are two major obstacles in their development. The complex and very sensitive nature of the body-mounted sensors means the traditional network layer security arrangements are not sufficient to employ their full potential, and novel solutions are necessary. In contrast, security methods based on physical layers tend to be more suitable and have simple requirements. The problem of initial trust needs to be addressed as a prelude to the physical layer security key arrangement. This paper proposes a patterns-of-life aided authentication model to solve this issue. The model employs the wireless channel fingerprint created by the user's behavior characterization. The performance of the proposed model is established through experimental measurements at 2.45 GHz. Experimental results show that high correlation values of 0.852 to 0.959 with the habitual action of the user in different scenarios can be used for auxiliary identity authentication, which is a scalable result for future studies.


Asunto(s)
Tecnología Inalámbrica , Redes de Comunicación de Computadores , Seguridad Computacional , Humanos , Monitoreo Ambulatorio
10.
Eur J Obstet Gynecol Reprod Biol ; 300: 54-62, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38986273

RESUMEN

BACKGROUND: It is widely recognized that depression is highly prevalent among women experiencing recurrent spontaneous abortion (RSA), exerting detrimental effects on both the individual and the family. OBJECTIVE: To assess the depression risk and associated factors among women with RSA. DATA SOURCES: Our search strategy encompassed PubMed, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure (CNKI), and WANFANG. The research was conducted in May 2022. We included both randomized and nonrandomized studies that reported the prevalence of depression among women with RSA. DATA EXTRACTION AND SYNTHESIS: Two independent evaluators reviewed the titles and abstracts, assessed the full-text papers, extracted data from the included studies, and evaluated their quality using the Newcastle-Ottawa Scale (NOS). We performed random-effects meta-analyses to pool the data. Odds ratios (ORs) and standardized mean differences (SMDs) were combined based on effect sizes for binary and continuous outcomes. MAIN OUTCOMES: To conduct a meta-analysis to understand the risk of depression in women with RSA who were not treated with psychiatric medications, as well as an analysis of potential factors for depressive symptoms. RESULTS: Out of the initially identified 527 papers, a total of 20 studies (N = 13087) that fulfilled the inclusion criteria were selected. Compared to healthy controls, patients with RSA had a significantly higher risk of depression (OR: 4.26, 95 % confidence interval [CI]: 2.44-7.41; SMD: 0.89, 95 % CI: 0.51-1.26). The occurrence of depression among RSA patients was found to be significantly associated with several factors including the severity of depressive symptoms (OR: 3.82, 95 % CI: 2.22-6.59), number of spontaneous miscarriages (SMD: 0.59, 95 % CI: 0.01-1.18), history of therapeutic termination of pregnancy (SMD: 0.20, 95 % CI: 0.09-0.32), history of live birth (SMD: -0.32, 95 % CI: -0.49--0.15), and duration of marriage (SMD: 0.15, 95 % CI: 0.02-0.27). CONCLUSIONS: In clinical practice, it is crucial to provide appropriate psychological interventions for women undergoing RSA. These individuals face a significantly heightened risk of depression, which exhibits strong correlations with various demographic factors such as the severity of depressive symptoms, history of both spontaneous miscarriages and therapeutic termination of pregnancy, number of live births, and duration of marriage. Consequently, women who are suffering RSA deserves more assistance and emotional support.


Asunto(s)
Aborto Habitual , Depresión , Femenino , Humanos , Embarazo , Aborto Habitual/epidemiología , Aborto Habitual/psicología , Depresión/epidemiología , Depresión/etiología , Depresión/terapia , Factores de Riesgo
11.
Artículo en Inglés | MEDLINE | ID: mdl-36478771

RESUMEN

WiFi sensing, an emerging sensing technology, has been widely used in vital sign monitoring. However, most respiration monitoring studies have focused on single-person tasks. In this paper, we propose a multi-person breathing sensing system based on WiFi signals. Specifically, we use radio frequency (RF) switch to extend the antennas to form switching antenna array. A reference channel is introduced in the receiver, which is connected to the transmitter by cable and attenuator. The phase offset introduced by asynchronous transceiver devices can be eliminated by using the ratio of the channel frequency response (CFR) between the antenna array and the reference channel. In order to realize multi-person breathing perception, we use beamforming technology to conduct two-dimensional scanning of the whole scene. After eliminating static clutter, we combine frequency domain and angle of arrival (AOA) domain analysis to construct the AOA and frequency (AOA-FREQ) spectrogram. Finally, the respiratory frequency and position of each target are obtained by clustering. Experimental results show that the proposed system can not only estimate the direction and respiration rate of multi-person, but also monitor abnormal respiration in multi-person scenarios. The proposed low-cost, non-contact, rapid multi-person respiratory detection technology can meet the requirements of long-term home health monitoring.

12.
J Phys Chem Lett ; 12(2): 958-965, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33443432

RESUMEN

Defects play non-negligible roles in many luminescent processes, where the significant and remarkable influence in the phosphor performance in various ways is observed. A full and clear perception of defects would be beneficial for the further development of the luminescence mechanism and design of phosphors. In this study, the defect-related luminescence in a chlorosilicate phosphor Ca2SiO3Cl2: Eu2+ was deeply studied. Except for the green emission originating from the d-f transition of the Eu2+ ion, a blue emission band with unique sensitivity to temperature and excitation energy was confirmed to be induced by the defects. The defects related to anion vacancies in the material acted as electron traps and luminescence centers simultaneously, which were well-identified by luminescence spectra and theory calculation analysis. This study uncovered the peculiar behavior and action mechanism of defects in the luminescence process and demonstrates a new path to understanding the origin of the luminescence center.

13.
IEEE J Biomed Health Inform ; 25(6): 2305-2316, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33290234

RESUMEN

Iatrogenic contamination causes serious health threats to both patients and healthcare staff. Contact operation is an important transmission route for nosocomial infection. Reducing direct contact during medical treatment can reduce nosocomial infection quickly and effectively. Scientific and technological progress in the 5G era brings new solutions to the problem of iatrogenic contamination. We conducted experiments at 27 GHz and 37 GHz to achieve contactless gesture recognition through the bornprint of body centric channel. The original channel S-parameters can achieve 82% (27 GHz) and 89% (37 GHz) basic recognition accuracy through simple statistical analysis. Basic switch recognition and multi-gesture selection recognition can meet the common operation requirements of circulating nurses, greatly reducing contact operations and reducing the probability of cross-contamination. Fully physically isolated body centric channel gesture sensing provides a new entry point for reducing iatrogenic contamination.


Asunto(s)
Gestos , Enfermeras y Enfermeros , Humanos
14.
ACS Appl Mater Interfaces ; 13(12): 14752-14758, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33729763

RESUMEN

Constructing composite electrodes is considered to be a feasible way to realize high-specific-capacity Li-ion batteries. The core-double-shell-structured Si@C@TiO2 would be an ideal design for such batteries, considering that carbon (C) can buffer the volume change and TiO2 can constrain the structural deformation of Si. Although the electrochemical performance of the shells themselves is relatively clear, the complexity of the multishell heterointerface always results in an ambiguous understanding about the influence of the heterointerface on the electrochemical properties of the core material. In this work, a multilayer film model that can simplify and simultaneously expand the area of the heterointerface is used to study the heterointerfacial behavior. First, a multilayer film TiO2/C with different numbers of TiO2/C heterointerfaces is studied. It shows that the electrochemical performance is enhanced apparently by increasing the number of TiO2/C heterointerfaces. On the one hand, the TiO2/C heterointerface exhibits a strong lithium-ion storage capacity. On the other hand, the TiO2/C heterointerface appears to effectively promote the local Li-ion concentration gradient and thus boost the Li-ion transport kinetics. Then, TiO2/C is combined with Si to construct a composite anode Si/C/TiO2. An obvious advantage of TiO2/C over single TiO2 and C is observed. The utilization rate of Si is greatly improved in the first cycle and reaches up to 98% in Si/C/TiO2. The results suggest that the electrochemical performance of Si can be greatly manipulated by the heterointerface between the multishells.

15.
Micromachines (Basel) ; 11(10)2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33008018

RESUMEN

The rapid spread of the novel coronavirus disease, COVID-19, and its resulting situation has garnered much effort to contain the virus through scientific research. The tragedy has not yet fully run its course, but it is already clear that the crisis is thoroughly global, and science is at the forefront in the fight against the virus. This includes medical professionals trying to cure the sick at risk to their own health; public health management tracking the virus and guardedly calling on such measures as social distancing to curb its spread; and researchers now engaged in the development of diagnostics, monitoring methods, treatments and vaccines. Recent advances in non-contact sensing to improve health care is the motivation of this study in order to contribute to the containment of the COVID-19 outbreak. The objective of this study is to articulate an innovative solution for early diagnosis of COVID-19 symptoms such as abnormal breathing rate, coughing and other vital health problems. To obtain an effective and feasible solution from existing platforms, this study identifies the existing methods used for human activity and health monitoring in a non-contact manner. This systematic review presents the data collection technology, data preprocessing, data preparation, features extraction, classification algorithms and performance achieved by the various non-contact sensing platforms. This study proposes a non-contact sensing platform for the early diagnosis of COVID-19 symptoms and monitoring of the human activities and health during the isolation or quarantine period. Finally, we highlight challenges in developing non-contact sensing platforms to effectively control the COVID-19 situation.

16.
ACS Nano ; 13(5): 5602-5610, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31013421

RESUMEN

Lithium-ion batteries (LIBs) have been considered as promising electrochemical energy storage devices due to the high volumetric, gravimetric capacity and high power density. The charge/discharge rate and power output of LIBs largely depend on the transport property of lithium-ions (Li-ions). The Li-ions diffusion coefficient and diffusion length are the critical factors influencing the charge/discharge rate of LIBs. In this work, we present that silicon-carbon (Si-C) interfaces in an amorphous Si/C multilayer electrode promote the transport of Li-ions along the direction not only perpendicular to but also parallel to the Si-C interfaces after electrode cracking. The electrode, stacked with 5 nm amorphous carbon and 10 nm amorphous Si, has the most stable solid-electrolyte interface (SEI) formed at the cracks, even when the Si is in direct contact with the electrolyte. It exhibits highly stable cycle performance and a high retained specific capacity. Electron microscopy characterization shows that the structure contains uniform Si/C multilayer blocks of about 1 µm. A micro-size hierarchical multilayer-block design strategy with proper stacking thickness of amorphous Si and carbon is thus proposed for high-performance film LIB anodes. Furthermore, the results may be used as a reference for the design of high-performance core-shell LIB anodes.

17.
IEEE J Transl Eng Health Med ; 7: 1800408, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31392103

RESUMEN

Parkinsonian gait is a defining feature of shaking palsy (SP) and it has one of the worse impacts on human healthy life than other SP symptoms. The objective of this work is to propose a Parkinsonian gait detection system based on an S-band perception technique to classify abnormal gait and normal walking. Due to the differences in the Gaits of Parkinson's patients compared with healthy persons, the wireless signals reflect and generates different variations at the receiver that could be used for SP diagnosis and classification. To detect a Parkinsonian gait, we first implement data preprocessing of the original data to obtain clear amplitude and phase information. Then, the feature extraction is carried out by principal component analysis (PCA). Finally, a support vector machine (SVM) classification algorithm is applied on collected data to classify the abnormal gait of SP patients compared with a normal gait. We evaluate the proposed system with different people, and the experimental outcomes show that the Parkinsonian gait detection of this training-based system achieves a high accuracy of above 90%. Moreover, the early warning of SP is achieved in a non-contact manner.

18.
Sci Rep ; 8(1): 3807, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-29491356

RESUMEN

Transformation Optics has been proven a versatile technique for designing novel electromagnetic devices and it has much wider applicability in many subject areas related to general wave equations. Among them, quasi-conformal transformation optics (QCTO) can be applied to minimize anisotropy of transformed media and has opened up the possibility to the design of broadband antennas with arbitrary geometries. In this work, a wide-angle scanning conformal phased array based on all-dielectric QCTO lens is designed and experimentally demonstrated. Excited by the same current distribution as such in a conventional planar array, the conformal system in presence of QCTO lens can preserve the same radiation characteristics of a planar array with wide-angle beam-scanning and low side lobe level (SLL). Laplace's equation subject to Dirichlet-Neumann boundary conditions is adopted to construct the mapping between the virtual and physical spaces. The isotropic lens with graded refractive index is realized by all-dielectric holey structure after an effective parameter approximation. The measurements of the fabricated system agree well with the simulated results, which demonstrate its excellent wide-angle beam scanning performance. Such demonstration paves the way to a robust but efficient array synthesis, as well as multi-beam and beam forming realization of conformal arrays via transformation optics.

19.
IEEE J Transl Eng Health Med ; 6: 2701008, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30464861

RESUMEN

A non-intrusive sleep apnea detection system using a C-Band channel sensing technique is proposed to monitor sleep apnea syndrome in real time. The system utilizes perturbations of RF signals to differentiate between patient's breathing under normal and sleep apnea conditions. The peak distance calculation is used to obtain the respiratory rates. A comparison of the datasets generated by the proposed method and a wearable sensor is made using a concordance correlation coefficient to establish its accuracy. The results show that the proposed sensing technique exhibits high accuracy and robustness, with more than 80% concordance with the wearable breathing sensor. This method is, therefore, a good candidate for the real-time wireless detection of sleep apnea.

20.
RSC Adv ; 8(12): 6660-6666, 2018 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35540414

RESUMEN

With a high specific capacity (4200 mA h g-1), silicon based materials have become the most promising anode materials in lithium-ions batteries. However, the large volume expansion makes the capacity reduce rapidly. In this work, a periodic silicon/carbon (Si/C) multilayer thin film was synthesized by magnetron sputtering method on copper foil. The titanium (Ti) film (about 20 nm) as the transition layer was deposited on the copper foil prior to the deposition of the multilayer film. Superior electrochemical lithium storage performance was obtained by the multilayer thin film. The initial discharge and charge specific capacity of the Si (15 nm)/C (5 nm) multilayer film anode are 2640 mA h g-1 and 2560 mA h g-1 with an initial coulombic efficiency of ∼97%. The retention specific capacity is about 2300 mA h g-1 and there is ∼87% capacity retention after 200 cycles.

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