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1.
J Ethnopharmacol ; 250: 112494, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31874213

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The lower back pain (LBP) caused by intervertebral disc (IVD) degeneration brings a heavy burden to society. A classic treatment method of Chinese medicine, fangji-duhuo jisheng decoction (DHJSD), has been effective in the clinical treatment of LBP, although the underlying mechanism remains unknown. AIM OF THE STUDY: In this work, the main objective was to study the effects of DHJSD on in vitro IVD degeneration of human nucleus pulposus (NP) cells after pressure treatment and on an in vivo interrupted IVD degeneration rat model. MATERIALS AND METHODS: The effects of DHJSD on the viability of NP cells were detected using Cell Counting Kit-8. RT-qPCR, western blotting, TUNEL assay, transmission electron microscopy, and immunofluorescence staining were performed to explore the molecular mechanism underlying protection against compression-induced matrix degradation and apoptosis in NP cells by DHJSD. Furthermore, the effects of DHJSD on IVD degeneration in a rat IDD model were also determined. RESULTS: We found that DHJSD increased the viability of NP cells in a concentration- and time-dependent manner. Furthermore, DHJSD significantly reduced compression-induced NP matrix degeneration and apoptosis, activated autophagy, and inhibited the p38/MAPK signaling pathway in NP cells subjected to compression. Autophagy inhibitor 3-MA and p38/MAPK signaling pathway activator anisomycin reversed the beneficial effects of DHJSD in NP cells, indicating that DHJSD protects against IVD degeneration by autophagy activation and P38/MAPK signaling pathway inhibition. Furthermore, DHJSD treatment effectively delayed IVD degeneration in a puncture-induced IDD rat model. CONCLUSIONS: DHJSD prevents compression-induced matrix degradation and cell apoptosis through regulating autophagy and the P38/MAPK signaling pathway. The mechanism underlying the effects of DHSJD elucidated in this study provides a new direction for LBP treatment.

2.
Nanotechnology ; 31(14): 144002, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31860888

RESUMO

Resistive switching devices have tremendous potential for memory, logic, and neuromorphic computing applications. Cation-based resistive switching devices intrinsically show nonvolatile memory characteristics under high compliance current (I CC), while show volatile threshold switching (TS) selector characteristics under low I CC. However, separate researches about cation-based memory or selector are hard to evade the typical current-retention dilemma, which results in the hardship to obtain low-current memory and high-current selector. Here, we propose a novel strategy to realize nonvolatile storage characteristics in a volatile TS device by modulating the rupture degree of conductive filament (CF). Enlarging the rupture degree of the CF with a certain RESET process, as confirmed by transmission electron microscope and energy dispersive spectrometry results, the threshold voltage of the Ag/HfO2/Pt TS devices can be enlarged from 0.9 to 2.8 V. Generation of the voltage difference enables the volatile TS devices the ability of self-selective nonvolatile storage. Increasing the RESET magnitude and shrinking the device size have been proved effective ways to increase the read window of the TS memory (TSM) devices. Evading the limit of the current-retention dilemma, ultra-low energy dissipation can be obtained by decreasing I CC to nA level. With self-selective, low-energy, and potential high-density integration characteristics, the proposed TSM device can act as a potential supplement of novel storage class memories.

3.
J Cell Biochem ; 120(10): 17459-17471, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271227

RESUMO

Cardiac development is a peculiar process involving coordinated cellular differentiation, migration, proliferation, and apoptosis. DNA methylation plays a key role in genomic stability, tissue-specific gene expression, cell proliferation, and apoptosis. Hypomethylation in the global genome has been reported in cardiovascular diseases. However, little is known about the impact and specific mechanism of global hypomethylation on cardiomyocytes. In the present study, we explored the impact of DNA methyltransferase inhibitors 5-azacytidine on cardiac development. In vivo experiment showed that hypomethylation of zebrafish embryos with 5-azacytidine exposure significantly reduced survival, induced malformations, and delayed general development process. Furthermore, zebrafish embryos injected with 5-azacytidine developed pericardial edema, ventricular volume reduction, looping deformity, and reduction in heart rate and ventricular shortening fraction. Cardiomyocytes treated with 5-azacytidine in vitro decreased proliferation and induced apoptosis in a concentration-dependent manner. Furthermore, 5-azacytidine treatment in cardiomyocytes resulted in 20 downregulated genes expression and two upregulated genes expression in 45 candidate genes, which indicated that DNA methylation functions as a bidirectional modulator in regulating gene expression. In conclusion, these results show the regulative effects of the epigenetic modifier 5-azacytidine in cardiac development of zebrafish embryos in vivo and cardiomyocyte proliferation and apoptosis and the homeostasis of gene expression in vitro, which offer a novel understanding of aberrant DNA methylation in the etiology of cardiovascular disease.

4.
ACS Appl Mater Interfaces ; 11(29): 25967-25975, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31259522

RESUMO

This work reports a moderate round-the-clock route to treating organic pollutants by utilizing a La2NiO4 hollow-sphere microreactor. A glycerol-assisted solvothermal route followed by an annealing process was applied for fabricating the catalyst. Both the physicochemical properties and the catalytic performance of the as-obtained microreactor for treating pollutants were discussed. The microreactor exhibited a strong ability to degrade phenol and anionic dyes in the absence of light irradiation, owing to its high surface area and positively charged surface. With the aid of visible-light irradiation, the degradation rate of the organic pollutants could be further accelerated due to the light multireflection in a hollow structure, which enhances the utilization of light. The present work indicates that the hollow-sphere La2NiO4 microreactor is effectively energy saving for environmental remediation.

5.
Obes Surg ; 29(8): 2535-2547, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31111342

RESUMO

BACKGROUND: Previous studies have reported that obesity can result in or worsen obstructive sleep apnea (OSA). However, whether abdominal or general obesity indices or visceral adiposity indicators have a stronger association with OSA remains unclear. METHODS: This cross-sectional study included 4344 patients who underwent polysomnography (PSG) due to suspicion of OSA. We also performed a longitudinal study on 86 patients who underwent bariatric surgery to confirm the relationship between OSA and obesity. Data on overnight PSG parameters, biochemical biomarkers, and multiple anthropometric obesity indices were collected. RESULTS: In the cross-sectional study, waist circumference (WC) and body mass index (BMI) were independently associated with the apnea-hypopnea index (AHI) after adjusting for potential confounding factors (additional R2 = 0.232, standardized beta coefficient [Beta] = 0.210; and additional R2 = 0.015, Beta = 0.183, respectively). Logistic regression analysis showed similar results, as did stratified analysis of adult males aged ≤ 55 years. Restricted cubic spline (RCS) analysis revealed a linear dose-response relationship between OSA and obesity. In the longitudinal study, no significant relationship was found between remission of OSA and improvement in WC and BMI (r = 0.252, p = 0.098; and r = 0.132, p = 0.395, respectively), whereas the change in the visceral adiposity indicator (lipid accumulation calculated according to WC and fasting triglycerides) was significantly correlated with ΔAHI (r = 0.322, p = 0.033). CONCLUSIONS: Abdominal obesity, rather than general obesity, appears to play a more important role in OSA.

6.
J Diabetes Res ; 2019: 9583286, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31089476

RESUMO

Both obstructive sleep apnea (OSA) and decreased serum lipoprotein(a) (Lp(a)) concentrations are associated with insulin resistance. However, their interaction effect on insulin resistance has never been investigated. Therefore, we performed a cross-sectional study on OSA-suspected Chinese Han participants. Laboratory-based polysomnographic variables, biochemical indicators, anthropometric measurements, and medical history were collected. Linear regression and binary logistic regression analyses with interaction terms were used to investigate the potential effects of the interaction between the severity of OSA (assessed by the apnea-hypopnea index (AHI)) and Lp(a) concentrations on insulin resistance (assessed by the homeostasis model assessment of insulin resistance (HOMA-IR)), after adjusting for potential confounders including age, gender, body mass index, waist-to-hip circumference ratio, mean arterial pressure, smoking status, drinking status, and lipid profiles. A total of 4,152 participants were enrolled. In the OSA-suspected population, AHI positively correlated with insulin resistance and serum Lp(a) concentrations independently and inversely correlated with insulin resistance. In addition, the interaction analysis showed that the linear association between lgAHI and lgHOMA-IR was much steeper and more significant in subjects with relatively low Lp(a) concentrations, suggesting a significant positive interaction between lgLp(a) and lgAHI on lgHOMA-IR (P = 0.013). Furthermore, the interaction on a multiplicative scale also demonstrated a significant positive interaction (P = 0.044). A stronger association between AHI quartiles and the presence of insulin resistance (defined as HOMA-IR > 3) could be observed for participants within lower Lp(a) quartiles. In conclusion, a significant positive interaction was observed between OSA and decreased Lp(a) with respect to insulin resistance. This association might be relevant to the assessment of metabolic or cardiovascular disease risk in OSA patients.


Assuntos
Resistência à Insulina/fisiologia , Lipoproteína(a)/sangue , Apneia Obstrutiva do Sono/sangue , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Doenças Cardiovasculares , China , Estudos de Coortes , Estudos Transversais , Feminino , Homeostase , Humanos , Resistência à Insulina/etnologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Polissonografia , Análise de Regressão , Risco , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/etnologia , Fumar
7.
Artigo em Inglês | MEDLINE | ID: mdl-31137662

RESUMO

Audio-visual interactions in green spaces are important for mental health and wellbeing. However, the influence of audio-visual interactions on psychological responses is still less clear. This study introduced a new method, namely the audio-visual walk (AV-walk), to obtain data on the audio-visual context, audio-visual experiences, and psychological responses in two typical parks, namely Cloves Park and Music Park in Harbin, China. Some interesting results are as follows: First, based on Pearson's correlation analysis, sound pressure level and roughness were significantly correlated with psychological responses in Cloves Park (p < 0.05). Second, the results of stepwise regression models showed the impact intensity of acoustic comfort was 1.64-1.68 times higher than that of visual comfort on psychological responses of emotion dimension, while visual comfort was 1.35-1.37 times higher than acoustic comfort on psychological responses of cognition dimension in Music Park. In addition, an orthogonal analysis diagram explained the influence of audio-visual interactions on psychological responses of young people. The audio-visual context located beside the waterscape with a relatively higher level of acoustic and visual comfort was the most cheerful (2.60), relaxed (2.45), and energetic (2.05), while the audio-visual context close to an urban built environment tended to be both acoustically and visually uncomfortable, and the psychological state was decreased to the most depressed (-0.25), anxious (-0.75), fatigued (-1.13) and distracted (-1.13).


Assuntos
Parques Recreativos , Som , Percepção Visual , Adulto , Ansiedade , Ambiente Construído , China , Depressão , Feminino , Humanos , Masculino , Relaxamento , Caminhada/psicologia , Adulto Jovem
8.
Materials (Basel) ; 12(10)2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31126087

RESUMO

The use of construction and demolition waste (CDW) to prepare recycled admixtures is of great significance for the complete resource reutilization of CDW. In this paper, different kinds of CDW were prepared into recycled powder (RP) with a specific particle size (0-45 µm or 0-75 µm). The fineness, water requirement ratio (WRR), fluidity, loss on ignition (LOI), strength activity index (SAI) and compatibility of cement and superplasticizer (CCS) were examined. The above test results were analyzed by advanced analysis tools, such as laser particle size analysis, XRD, XRF, DSC-TGA, SEM, and BET. The properties of different types of RPs varied greatly, which was closely related to the microstructure, particle morphology and chemical composition of the RP. The experimental results showed that all kinds of RPs after grinding had a high fineness and good particle size distribution, and the mineral composition was dominated by SiO2 with the content exceeding 50%. The WRR of various RPs was between 105% and 112%, and the SAI was between 68% and 78%, but the LOI varied greatly. Different types of RPs had a negative impact on the CCS, but the compatibility of cement and naphthalene-based superplasticizer was less affected. The content of recycled brick powder (RBP) in a hybrid recycled powder (HRP) was an important factor. When the content of RBP in HRP exceeded 50%, the HRP could meet the basic performance requirements of fly ash.

9.
ACS Appl Mater Interfaces ; 11(18): 16527-16537, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30990659

RESUMO

Graphitic carbon nitride (g-C3N4) fundamental photophysical processes exhibit a high frequency of charge trapping due to physicochemical defects. In this study, a copper phosphide (Cu3P) and g-C3N4 hybrid was synthesized via a facile phosphorization method. Cu3P, as an electron acceptor, efficiently captures the photogenerated electrons and drastically improved the charge separation rate to cause a significantly enhanced photocatalytic performance. Moreover, the robust and intimate chemical interactions between Cu3P and g-C3N4 offers a rectified charge-transfer channel that can lead to a higher H2 evolution rate (HRE, 277.2 µmol h-1 g-1) for this hybrid that is up to 370 times greater than that achieved from using bare g-C3N4 (HRE, 0.75 µmol h-1 g-1) with a quantum efficiency of 3.74% under visible light irradiation (λ = 420 nm). To better determine the photophysical characteristics of the Cu3P-induced charge antitrapping behavior, ultrafast time-resolved spectroscopy measurements were used to investigate the charge carriers' dynamics from femtosecond to nanosecond time domains. The experimental results clearly revealed that Cu3P can effectively enhance charge transfer and suppress photoelectron-hole recombination.

10.
J Org Chem ; 84(11): 6719-6728, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31021088

RESUMO

[3 + 2] cycloaddition of para-quinone methides with nitrile imines under mild conditions has been achieved. The corresponding spiro-pyrazoline-cyclohexadienone products were constructed in good to excellent yields (up to 97% yield) with high regioselectivity. This straightforward protocol exhibits good functional group tolerance and scalability and provides the spiro-pyrazoline-cyclohexadienones.

11.
Carbohydr Polym ; 215: 20-28, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30981346

RESUMO

Inspired by the mussel foot protein and chitosan-based macromolecular adhesives, a series of chitosan-graft-polypeptides were synthesized by ring-opening polymerization of three N-carboxyanhydrides (NCAs) - 3,4-dihydroxyphenylalanine-N-carboxyanhydride (DOPA-NCA), cysteine-NCA (Cys-NCA) and arginine-NCA (Arg-NCA) - using partial-NH2-protected chitosan as an initiator. These copolymers demonstrated good biodegradability and low cytotoxicity. The results of lap-shear adhesion test showed that the maximum lap-shear adhesion strength on the porcine skin and aluminum sheet were 195.97 ± 21.1 kPa and 3080 ± 320 kPa, respectively, and the maximum tensile adhesion strength on bone was 642.70 ± 61.1 kPa. The rat experiment in vivo showed that these copolymers exhibited good hemostatic performance and can promote the healing of skin wound and bone fracture. It is expected that thesecopolymeric adhesives will have broad applications in hemostasis and soft tissue adhesions.


Assuntos
Adesivos/química , Materiais Biomiméticos/química , Quitosana/análogos & derivados , Hemostáticos/química , Peptídeos/química , Adesivos Teciduais/química , Adesivos/síntese química , Adesivos/farmacologia , Adesivos/uso terapêutico , Alumínio/química , Animais , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/farmacologia , Materiais Biomiméticos/uso terapêutico , Cobre/química , Consolidação da Fratura/efeitos dos fármacos , Fraturas Ósseas/terapia , Hemostasia/efeitos dos fármacos , Hemostáticos/síntese química , Hemostáticos/farmacologia , Hemostáticos/uso terapêutico , Masculino , Peptídeos/síntese química , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Polimerização , Ratos , Suínos , Adesivos Teciduais/síntese química , Adesivos Teciduais/farmacologia , Adesivos Teciduais/uso terapêutico , Cicatrização/efeitos dos fármacos
12.
J Mol Cell Biol ; 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30941422

RESUMO

Chronic inflammation plays a pivotal role in insulin resistance and type 2 diabetes, yet the mechanisms are not completely understood. Here, we demonstrated that serum LPS levels were significantly higher in newly diagnosed diabetic patients than in normal control. miR-145 level in peripheral blood mononuclear cells decreased in type 2 diabetics. LPS repressed the transcription of miR-143/145 cluster and decreased miR-145 levels. Attenuation of miR-145 activity by anti-miR-145 triggered liver inflammation and increased serum chemokines in C57BL/6 J mice. Conversely, lentivirus-mediated miR-145 overexpression inhibited macrophage infiltration, reduced body weight, and improved glucose metabolism in db/db mice. And miR-145 overexpression markedly reduced plaque size in the aorta in ApoE-/- mice. Both OPG and KLF5 were targets of miR-145. miR-145 repressed cell proliferation and induced apoptosis partially by targeting OPG and KLF5. miR-145 also suppressed NF-kB activation by targeting OPG and KLF5. Our findings provide an association of the environment with the progress of metabolic disorders. Increasing miR-145 may be a new potential therapeutic strategy in preventing and treating metabolic diseases such as type 2 diabetes and atherosclerosis.

13.
Micromachines (Basel) ; 10(3)2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30823452

RESUMO

Small volume changes are important factors that restrict the improvement of the performance of a piezoelectric diaphragm pump. In order to increase the volume change of the pump chamber, a square piezoelectric vibrator with a flexible support is proposed in this paper and used as the driving unit of the pump. The pump chamber diaphragm was separated from the driving unit, and the resonance principle was used to amplify the amplitude of the pump diaphragm. After analyzing the working principle of the piezoelectric resonance pump and establishing the motion differential equation of the vibration system, prototypes with different structural parameters were made and tested. The results show that the piezoelectric resonance pump resonated at 236 Hz when pumping air. When the peak-to-peak voltage of the driving power was 220 V, the amplitude of the diaphragm reached a maximum value of 0.43933 mm, and the volume change of the pump was correspondingly improved. When the pump chamber height was 0.25 mm, the output flow rate of pumping water reached a maximum value of 213.5 mL/min. When the chamber height was 0.15 mm, the output pressure reached a maximum value of 85.2 kPa.

14.
J Clin Hypertens (Greenwich) ; 21(2): 280-290, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30667162

RESUMO

Previous studies have reported the effects of obstructive sleep apnea (OSA) and cardiometabolic disorders on cardiovascular disease (CVD), but associations between cardiometabolic biomarkers and two cardinal features of OSA (chronic intermittent hypoxia and sleep fragmentation) and their interactions on CVD in OSA populations remain unclear. A total of 1727 subjects were included in this observational study. Data on overnight polysomnography parameters, biochemical biomarkers, and anthropometric measurements were collected. Metabolic syndrome (MS), including blood pressure, waist circumference (WC), fasting glucose, triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C), was diagnosed based on modified criteria of the Adult Treatment Panel III. WC, mean arterial pressure, TG and low-density lipoprotein cholesterol (LDL-C) were independently associated with apnea-hypopnea index (AHI) after adjustment for confounding factors (ß = 0.578, P = 0.000; ß = 0.157, P = 0.001; ß = 1.003, P = 0.019; and ß = 4.067, P = 0.0005, respectively). Furthermore, the interaction analysis revealed joint effects between hypertension, obesity, hyperglycemia, and LDL-C dyslipidemia and AHI on CVD. The relative excess risks of CVD due to the interactions with OSA were 2.06, 1.02, 0.48, and 1.42, respectively (all P < 0.05). In contrast, we found no independent effect of the microarousal index (MAI) on CVD. However, LDL-C level and some MS components (WC, TG) were associated with MAI. Our findings indicate that hypoxemia and cardiometabolic disorders in OSA may potentiate their unfavorable effects on CVD. Sleep fragmentation may indirectly predispose patients with OSA to an increased risk of CVD. Thus, cardiometabolic disorders and OSA synergistically influence cardiometabolic risk patterns.

15.
Oncol Lett ; 17(2): 1791-1797, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30675239

RESUMO

The expression of micro-ribonucleic acid miR-664 and miR-184 on the biological characteristics of osteosarcoma (OS) SOSP-9607 cells was investigated. Eighteen surgical specimens of OS and 18 normal tissue specimens were collected. The expression of miR-664 and miR-184 was detected via fluorescence reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The OS cell line SOSP-9607 was selected as the object of study, and miR-664 blank group, miR-664 mimic group, miR-664 inhibitor group, miR-184 blank group, miR-184 mimic group and miR-184 inhibitor group were established through transfection. Changes in apoptosis were detected via flow cytometry, the cell proliferation capacity was detected via Cell Counting Kit-8 assay, and the cell migration was observed via wound healing assay. In cancer tissues of OS patients, the relative expression of miR-664 and miR-184 was significantly higher than that in para-carcinoma tissues (P<0.05). The cell growth in miR-664 inhibitor group was obviously decreased compared with those in miR-664 blank and mimic groups (P<0.05). There were differences in the cell migration capacity among groups (P<0.01), and the cell scratch areas in miR-664 and miR-184 mimic groups were significantly decreased compared with those in miR-664 and miR-184 blank groups (P<0.05), while they were significantly increased in miR-664 and miR-184 inhibitor groups compared with those in miR-664 and miR-184 blank and mimic groups (P<0.05, P<0.01). There were differences in the apoptosis rate among groups (P<0.01) and apoptosis in miR-664 and miR-184 inhibitor groups was remarkably increased compared with those in miR-664 and miR-184 blank and mimic groups (P<0.05). Downregulating the expression of miR-664 and miR-184 may promote apoptosis, inhibit the proliferation and reduce the migration capacity of SOSP-9607 cells. Therefore, miR-664 and miR-184 may provide a theoretical basis for the target selection in clinical targeted therapy and drug development for OS.

16.
BMC Pulm Med ; 19(1): 18, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30658615

RESUMO

BACKGROUND: The high cost and low availability of polysomnography (PSG) limits the timely diagnosis of OSA. Herein, we developed and validated a simple-to-use nomogram for predicting OSA. METHODS: We collected and analyzed the cross-sectional data of 4162 participants with suspected OSA, seen at our sleep center between 2007 and 2016. Demographic, biochemical and anthropometric data, as well as sleep parameters were obtained. A least absolute shrinkage and selection operator (LASSO) regression model was used to reduce data dimensionality, select factors, and construct the nomogram. The performance of the nomogram was assessed using calibration and discrimination. Internal validation was also performed. RESULTS: The LASSO regression analysis identified age, sex, body mass index, neck circumference, waist circumference, glucose, insulin, and apolipoprotein B as significant predictive factors of OSA. Our nomogram model showed good discrimination and calibration in terms of predicting OSA, and had a C-index value of 0.839 according to the internal validation. Discrimination and calibration in the validation group was also good (C-index = 0.820). The nomogram identified individuals at risk for OSA with an area under the curve (AUC) of 0.84 [95% confidence interval (CI), 0.83-0.86]. CONCLUSIONS: Our simple-to-use nomogram is not intended to replace standard PSG, but will help physicians better make decisions on PSG arrangement for the patients referred to sleep center.


Assuntos
Nomogramas , Apneia Obstrutiva do Sono/diagnóstico , Adulto , Fatores Etários , Antropometria , Apolipoproteínas B/metabolismo , Área Sob a Curva , Glicemia/metabolismo , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Pescoço/anatomia & histologia , Polissonografia , Análise de Regressão , Fatores Sexuais , Apneia Obstrutiva do Sono/epidemiologia , Circunferência da Cintura
17.
Materials (Basel) ; 11(11)2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30373122

RESUMO

Synaptic devices with bipolar analog resistive switching behavior are the building blocks for memristor-based neuromorphic computing. In this work, a fully complementary metal-oxide semiconductor (CMOS)-compatible, forming-free, and non-filamentary memristive device (Pd/Al2O3/TaOx/Ta) with bipolar analog switching behavior is reported as an artificial synapse for neuromorphic computing. Synaptic functions, including long-term potentiation/depression, paired-pulse facilitation (PPF), and spike-timing-dependent plasticity (STDP), are implemented based on this device; the switching energy is around 50 pJ per spike. Furthermore, for applications in artificial neural networks (ANN), determined target conductance states with little deviation (<1%) can be obtained with random initial states. However, the device shows non-linear conductance change characteristics, and a nearly linear conductance change behavior is obtained by optimizing the training scheme. Based on these results, the device is a promising emulator for biology synapses, which could be of great benefit to memristor-based neuromorphic computing.

19.
Artigo em Inglês | MEDLINE | ID: mdl-29893026

RESUMO

Numerous studies have observed a relationship between obstructive sleep apnea and hypertension, but the effects of metabolic syndrome on hypertension, and their interaction with obstructive sleep apnea, remain unclear. For this study, a total of 2972 patients were recruited from the Shanghai Sleep Health Study. Data from overnight polysomnography parameters, serum lipids, fasting blood glucose, blood pressure, and anthropometric measurements were collected. The authors then explored the independent associations and multiplicative and additive interactions of predictors of metabolic syndrome with hypertension. A positive dose-response relationship was observed between systolic blood pressure and diastolic blood pressure and quartiles of fasting glucose, triglyceride, low-density lipoprotein cholesterol, body mass index, and apnea-hypopnea index. Furthermore, logistic regression analysis showed that, in men, a high triglyceride level, hyperglycemia, and overweight status (and their interaction effect on obstructive sleep apnea) were associated with hypertension. Being overweight and hyperglycemic may markedly augment the adverse effect of obstructive sleep apnea on hypertension in men. Therefore, hypertension therapy should be individualized based on the specific comorbidities of each patient.

20.
Materials (Basel) ; 11(4)2018 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-29690613

RESUMO

In this study, graphene oxides with different functionalization degrees were prepared by a facile one-step hydrothermal reflux method at various reaction temperatures using graphene oxide (GO) as starting material and p-phenylenediamine (PPD) as the modifier. The effects of reaction temperature on structure, appearance and bonding type of the obtained materials were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The results showed that when the reaction temperature was 10⁻70 °C, the GO reacted with PPD through non-covalent ionic bonds (⁻COO−H3⁺N⁻R) and hydrogen bonds (C⁻OH…H2N⁻X). When the reaction temperature reached 90 °C, the GO was functionalized with PPD through covalent bonds of C⁻N. The crystal structure of products became more ordered and regular, and the interlayer spacing (d value) and surface roughness increased as the temperature increased. Furthermore, the results suggested that PPD was grafted on the surface of GO through covalent bonding by first attacking the carboxyl groups and then the epoxy groups of GO.

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