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1.
ACS Appl Mater Interfaces ; 15(16): 20334-20345, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37040205

RESUMO

Thermal-acoustic devices have great potential as flexible ultrathin sound sources. However, stretchable sound sources based on a thermal-acoustic mechanism remain elusive, as realizing stable resistance in a reasonable range is challenging. In this study, a stretchable thermal-acoustic device based on graphene ink is fabricated on a weft-knitted fabric. After optimization of the graphene ink concentration, the device resistance changes by 8.94% during 4000 cycles of operation in the unstretchable state. After multiple cycles of bending, folding, prodding, and washing, the sound pressure level (SPL) change of the device is within 10%. Moreover, the SPL has an increase with the strain in a specific range, showing a phenomenon similar to the negative differential resistance (NDR) effect. This study sheds light on the use of stretchable thermal-acoustic devices for e-skin and wearable electronics.

2.
Sci Adv ; 8(13): eabn2156, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35353573

RESUMO

We report an artificial eardrum using an acoustic sensor based on two-dimensional MXene (Ti3C2Tx), which mimics the function of a human eardrum for realizing voice detection and recognition. Using MXene with a large interlayer distance and micropyramid polydimethylsiloxane arrays can enable a two-stage amplification of pressure and acoustic sensing. The MXene artificial eardrum shows an extremely high sensitivity of 62 kPa-1 and a very low detection limit of 0.1 Pa. Notably, benefiting from the ultrasensitive MXene eardrum, the machine-learning algorithm for real-time voice classification can be realized with high accuracy. The 280 voice signals are successfully classified for seven categories, and a high accuracy of 96.4 and 95% can be achieved by the training dataset and the test dataset, respectively. The current results indicate that the MXene artificial intelligent eardrum shows great potential for applications in wearable acoustical health care devices.

3.
Nanomaterials (Basel) ; 13(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36616089

RESUMO

Electronic skin (e-skin) has attracted tremendous interest due to its diverse potential applications, including in physiological signal detection, health monitoring, and artificial throats. However, the major drawbacks of traditional e-skin are the weak adhesion of substrates, incompatibility between sensitivity and stretchability, and its single function. These shortcomings limit the application of e-skin and increase the complexity of its multifunctional integration. Herein, the synergistic network of crosslinked SWCNTs within and between multilayered graphene layers was directly drip coated onto the PU thin film with self-adhesion to fabricate versatile e-skin. The excellent mechanical properties of prepared e-skin arise from the sufficient conductive paths guaranteed by SWCNTs in small and large deformation under various strains. The prepared e-skin exhibits a low detection limit, as small as 0.5% strain, and compatibility between sensitivity and stretchability with a gauge factor (GF) of 964 at a strain of 0-30%, and 2743 at a strain of 30-60%. In physiological signals detection application, the e-skin demonstrates the detection of subtle motions, such as artery pulse and blinking, as well as large body motions, such as knee joint bending, elbow movement, and neck movement. In artificial throat application, the e-skin integrates sound recognition and sound emitting and shows clear and distinct responses between different throat muscle movements and different words for sound signal acquisition and recognition, in conjunction with superior sound emission performance with a sound spectrum response of 71 dB (f = 12.5 kHz). Overall, the presented comprehensive study of novel materials, structures, properties, and mechanisms offers promising potential in physiological signals detection and artificial throat applications.

4.
World J Surg Oncol ; 18(1): 129, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539858

RESUMO

BACKGROUND: The survival outcomes of neoadjuvant chemotherapy (NACT) versus adjuvant chemotherapy (ACT) for patients with triple-negative breast cancer (TNBC) remain unclear. Therefore, in this study, a meta-analysis was conducted to analyze current evidence on the survival outcomes of NACT versus ACT in TNBC. METHODS: A systematic search was performed on the PubMed and Embase databases to identify relevant articles investigating the survival outcomes of NACT versus ACT in TNBC. RESULTS: A total of nine studies involving 36,480 patients met the selection criteria. Among them, 10,728 (29.41%) received NACT, and 25,752 (70.59%) received ACT. The pathological complete response (pCR) rate was 35% (95% CI = 0.23-0.48). Compared with ACT, the overall survival (OS) of NACT was poor (HR = 1.59; 95% CI = 1.25-2.02; P = 0.0001), and there was no significant difference in disease-free survival (DFS) between the two treatments (HR = 0.85; 95% CI = 0.54-1.34; P = 0.49). NACT with pCR significantly improved the OS (HR = 0.53; 95% CI = 0.29-0.98; P = 0.04) and DFS (HR = 0.52; 95% CI = 0.29-0.94; P = 0.03), while the OS (HR = 1.18; 95% CI = 1.09-1.28; P < 0.0001) and DFS (HR = 2.36; 95% CI = 1.42-3.89; P = 0.0008) of patients with residual disease (RD) following NACT were worse compared to those receiving ACT. CONCLUSION: These findings suggest that, for TNBC, NACT with pCR is superior to ACT in improving OS and DFS, and it turns to be opposite when patients are receiving NACT with RD.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante/mortalidade , Terapia Neoadjuvante/mortalidade , Neoplasias de Mama Triplo Negativas/mortalidade , Feminino , Humanos , Prognóstico , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
6.
Phys Rev Lett ; 123(20): 206601, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31809106

RESUMO

Recently discovered Dirac semimetals (DSMs) with two Dirac nodes, such as Na_{3}Bi and Cd_{2}As_{3}, are regarded as carrying the Z_{2} topological charge in addition to the chiral charge. We study the Floquet phase transition of Z_{2} topological DSMs subjected to a beam of circularly polarized light. Owing to the resulting interplay of the chiral and Z_{2} charges, the Weyl nodes are not only chirality dependent but also spin dependent, which constrains the behavior in creation and annihilation of the pair of Weyl nodes. Interestingly, we find a novel phase: One spin band is in the Weyl semimetal phase while the other is in the insulator phase, and we dub it the Weyl half-metal (WHM) phase. We further study the spin-dependent transport in a Dirac-Weyl semimetal junction and find a spin filter effect as a fingerprint of the existence of the WHM phase. The proposed spin filter effect, based on the WHM bulk band, is highly tunable in a broad parameter regime and robust against magnetic disorder, which is expected to overcome the shortcomings of the previously proposed spin filter based on the topological edge or surface states. Our results offer a unique opportunity to explore the potential applications of topological DSMs in spintronics.

7.
Phytomedicine ; 61: 152829, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31039532

RESUMO

BACKGROUND: Quality control of herbal medicines based on characteristic components is an important trend. Although the plant metabolomics provide a powerful tool for species classification, the discovered marker is usually limited in practical application. For rapid discovery of efficient marker combination, we proposed a strategy integrating targeted metabolite profiling and sequential optimization method. METHODS: This strategy included: (1) directional enrichment and chemical profiling of targeted metabolites by matrix solid phase dispersion (MSPD) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). (2) Partial least squares discrimination analysis (PLS-DA)-based sequential screening of efficient marker combination was constructed for various species predictions. Five Lonicera species and their characteristic metabolites, sponins, were taken as a case study. RESULTS: A total of 19 saponins were identified, and 12 major and available saponins were enriched based on MSPD and quantified by LC-MS/MS in 5 Lonicera species flower buds. Followed by 3 runs of PLS-DA-based screening, a combination consisting of macranthoidin B, dipsacoside B and α-hederin was discovered as the effective chemical marker for 5 analogous Lonicera flower classification. CONCLUSION: Our study provides an effective and applicable approach to select the practical marker combination for the assessment of analogical herb medicines.


Assuntos
Cromatografia Líquida/métodos , Lonicera/química , Lonicera/metabolismo , Metabolômica/métodos , Espectrometria de Massas em Tandem/métodos , Biomarcadores/análise , Biomarcadores/metabolismo , Flores/química , Flores/metabolismo , Análise dos Mínimos Quadrados , Metabolômica/estatística & dados numéricos , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/análise , Ácido Oleanólico/metabolismo , Plantas Medicinais/química , Saponinas/análise , Saponinas/metabolismo , Especificidade da Espécie , Espectrometria de Massas em Tandem/estatística & dados numéricos
8.
Phytomedicine ; 51: 104-111, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30466607

RESUMO

BACKGROUND: Macroscopic identification has been widely used as a convenient method for herbal authentication and quality assessment. However, sensory evaluation heavily relied on personal experience and lacked enough evidence-based validations. PURPOSE: We aim to reveal the correlation between macroscopic characteristics and tissue-specific chemical composition of the root of Salvia miltiorrhiza (SMR), and then develop a rapid method for quality assessment. METHODS: Thirty-two batches of SMR were collected and evaluated. The outer-surface color and diameter as the representative tissue features of SMR were selected as the macroscopic indexes. SMR were then divided into three parts along transverse section as outer bark, middle part and central part, to explore the spatial distribution of chemicals. Outer-surface color information was converted into RGB values, while the diameter data were expressed by mean distance, respectively. Thirteen major components including eight salvianolic acids and five tanshinones in each part were determined by liquid chromatography tandem mass spectrometry. Finally, several mathematical models were established and optimized to evaluate the correlation between outer-surface color, size and chemical distribution. RESULT: All five tanshinones mainly distributed in the outer bark while salvianolic acids were averagely existed among three parts. Correlational studies revealed that the surface color depth was significantly and positively correlated with tanshinone contents in the outer bark, while the size showed poor correlation in any chemicals. A color-oriented model was thus developed for the prediction of tanshinone contents in SMR, and a 9 × 9 standard color chart was created for easily use. CONCLUSION: This study contributes an alternative method for macroscopic features-based quality evaluation of herbs, and also complements some scientific data for traditional knowledge.


Assuntos
Raízes de Plantas/química , Salvia miltiorrhiza/química , Abietanos/análise , Alcenos/análise , Cromatografia Líquida de Alta Pressão , Cor , Medicamentos de Ervas Chinesas/química , Polifenóis/análise , Espectrometria de Massas em Tandem
9.
Springerplus ; 5(1): 1052, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27462500

RESUMO

We evaluated a non-invasive method for predicting the ovarian function of premenopausal breast cancer patients with amenorrhoea after chemotherapy. A total of 34 patients had ovarian function, whereas 56 had no ovarian function. Logistic regression analysis indicated that age (P = 0.034; hazards ratio [HR], 0.29; confidence interval [CI], 0.091-0.910), follicle-stimulating hormone (P = 0.032; HR 0.97; CI 0.944-0.997) and oestradiol (P = 0.047; HR 1.01; CI 1.000-1.015) were independent influencing factors that determine ovarian function. The ovarian function score (OFS) (P < 0.001; HR 48.00; CI 10.174-226.452) was obtained through a comprehensive analysis of these three variables, and it could more effectively predict ovarian function. According to receiver operating characteristic curve analysis, the OFS had the highest values compared with the other three variables (sensitivity, 94.6 %; specificity, 79.3 %). The OFS is simple and easy to use; thus, it is expected to become a new method for determining drug-induced amenorrhoea in women with breast cancer. Ovarian function likely still exists if the OFS is ≤1.

10.
Journal of Experimental Hematology ; (6): 1269-1274, 2016.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-246777

RESUMO

The PI3K/Akt/mTOR signaling pathway plays a central role in cell growth, proliferation and survival in physiological conditions. This signal pathway is considered to be an innovative targeted therapy of cancer, and its abnormal activation has been proved to be related to T-cell acute lymphoblastic leukemia (T-ALL) .Despite improved treatment strategies, such as multi-drug combination, high-dose chemotherapy and all kinds of application and popularization of hematopoietic stem cell transplantation, children with drug resistance or relapse T-ALL are still rather worse and its overall outcome and prognosis are much poorer than the more common B-lineage ALL. Therefore, more effective and less cytotoxic treatment targeted strategies for leukemia greatly needed. This review focuses on the relationship between the PI3k/Akt/mTOR pathway and the pediatric T-ALL, so as to reveal the exact molecular mechanism of T-ALL and provide more directions for its treatment.


Assuntos
Criança , Humanos , Proliferação de Células , Fosfatidilinositol 3-Quinases , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 899-904, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197571

RESUMO

Aiming to discuss the change characteristic of macromolecular structures of high rank coal in different rheological conditions, the high rank undeformed coal from southern Qinshui basin and the coal after variable temperature and variable pressure rheology experiments were investigated and analyzed in detail through Fourier transform infrared spectroscopy (FTIR) and laser Raman spectra analysis. The result shows that the texture and composition of different types of rheological coals under different temperature and pressure exhibit significant differences. Experiments of variable temperature and pressure of high rank coal (temperature: 300-400 °C, confining pressure: 50-100 MPa, strain: less than 10% and strain rate: 10(-4)-10(-7) · s(-1) will distort their macromolecular structures and recombine the chemistry structures. When the temperature is 300 °C or 350 °C, the high rank coal generates brittle or brittle-ductile rheology easily, mechanical energy transforms to heat energy, some branches and functional groups with weaker bond energy break and fall off, which split as dissociative micromolecule, with stress degradation as principal role, and stress polycondensation occurs with aromatic, texture increasing. When the temperature is up to 400 °C, ductile rheology of the high rank coal occurs with the secondary defects increasing, mechanical energy transforms to strain energy which helps the early shedding small molecules be embedded or adsorbed in the defect or on the surface of macromolecular preferentially and change the aliphatic and aromatic structures. It is affected by stress degradation and polycondensation progress, and the latter is dominated. The confining pressure and water injection of coal do not have much effect on the macromolecular structure obviously.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 603-8, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26117863

RESUMO

Hydrocarbon generation and structural evolution would be occurred in the process of from coal-forming material (i. e. peat sample) transforming to the coal. While Fourier Transform Infrared Spectroscopy (FTIR) have a special advantages in analyzing molecular structure of samples. For understanding the characteristics of hydrocarbon generation and structural evolution of coal-forming material during the process of pyrolysis and microbial degradation, based on the physical simulation experiments of closed pyrolysis and anaerobic microbial degradation, the generation potential of thermogenic gas and biogenic gas were studied in this paper, and characteristics of molecular structure evolution and its mechanism was analyzed by FTIR technology. Results show that cumulative gas yields of hydrocarbon gases (mainly for methane) increased with experiment temperature. The gas yield of non-hydrocarbon gas (mainly for CO2) exhibited two peaks at 250 and 375 degrees C. The degradation ability of anaerobe on coal samples weakened with the maturity increasing and there was no gas generation on the pyrolysis samples with maturity from 1.6% to 1.8%. After pyrolysis, the content of hydroxyl in peat sample decreased first and then increased with the pyrolysis temperature increasing. The content of aldehyde carbonyl, methylene and phosphate reduced. The content of aromatic esters decreased with nonlinear. The bone of S-O in stretching vibration appeared after 350 degrees C and its content increased with temperature. This shows that the sulfocompound restrains the activity of methanogenic bacteria. After degradation by anaerobe, the relative content of hydroxyl, aldehyde carbonyl, aromatic esters, methylene and phosphate in peat sample dropped significantly. It is shown that the intermolecular force between these groups weakened.


Assuntos
Hidrocarbonetos/análise , Microbiologia do Solo , Solo/química , Carvão Mineral , Gases , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
13.
Zhonghua Nan Ke Xue ; 19(2): 144-8, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23441456

RESUMO

OBJECTIVE: To study the etiology, clinical manifestation, diagnosis and treatment of giant prostatic calculus with neurogenic bladder disease and prostate diverticulum. METHODS: We retrospectively analyzed the clinical data of a case of giant prostatic calculus with neurogenic bladder disease and prostate diverticulum and reviewed the relevant literature. The patient was a 37-year-old man, with urinary incontinence for 22 years and intermittent dysuria with frequent micturition for 9 years, aggravated in the past 3 months. He had received surgery for spina bifida and giant vesico-prostatic calculus. The results of preoperative routine urinary examination were as follows: WBC 17 -20/HPF, RBC 12 - 15/HPF. KUB, IVU and pelvic CT revealed spina bifida occulta, neurogenic bladder and giant prostatic calculus. RESULTS: The patient underwent TURP and transurethral lithotripsy with holmium-YAG laser. The prostatic calculus was carbonate apatite in composition. Urinary dynamic images at 2 weeks after surgery exhibited significant improvement in the highest urine flow rate and residual urine volume. Seventeen months of postoperative follow-up showed dramatically improved urinary incontinence and thicker urine stream. CONCLUSION: Prostate diverticulum with prostatic giant calculus is very rare, and neurogenic bladder may play a role in its etiology. Cystoscopy is an accurate screening method for its diagnosis. For the young patients and those who wish to retain sexual function, TURP combined with holmium laser lithotripsy can be employed, and intraoperative rectal examination should be taken to ensure complete removal of calculi.


Assuntos
Cálculos/complicações , Divertículo/complicações , Doenças Prostáticas/complicações , Bexiga Urinaria Neurogênica/complicações , Adulto , Humanos , Masculino
14.
Zhonghua Yi Xue Za Zhi ; 92(15): 1017-22, 2012 Apr 17.
Artigo em Chinês | MEDLINE | ID: mdl-22781640

RESUMO

OBJECTIVE: To assess the therapeutic effect of Xuebijing injection on adult patients with acute respiratory distress syndrome (ARDS). METHODS: A multicenter prospective randomized control study was conducted at 10 intensive care units in Jiangsu province. A total of 172 early ARDS patients were randomly divided into Xuebijing treatment and control groups. All patients received routine therapy of ARDS while additional Xuebijing injection 100 ml was administered in the treatment group intravenously for 7 days. Lung injury score, acute physiology and chronic health evaluation II (APACHE II) score, multiple organ dysfunction score (MODS) and PaO2/FiO2 of the patients was recorded before and after treatment. Mortality at 28 days and the duration of mechanical ventilation were compared between two groups. RESULTS: Ninety-one patients were assigned to receive Xuebijing injection and 81 patients as control; Mortality at Days 28 and 90, the duration of mechanical ventilation and ventilation free days showed no difference between two groups (P > 0.05). PaO2/FiO2 improved after randomization versus pre-treatment in all patients. There was no significant difference between two groups. Murray scores were not significantly different between two groups. In a subgroup analysis of patients with pulmonary infection, pulmonary contusion and extra-pulmonary cause, two groups had no difference in mortality at Day 28, mortality at Day 90, the duration of mechanical ventilation, ventilation free days and days of ICU stay (P > 0.05). CONCLUSION: The treatment of Xuebijing injection early in course of ARDS does not improve the mortality of ARDS patients. But it may improve lung function and oxygenation. Further studies are warranted.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Síndrome do Desconforto Respiratório/mortalidade , Taxa de Sobrevida , Resultado do Tratamento
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2176-82, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22007412

RESUMO

The structural and compositive evolution of tectonically deformed coals (TDCs) and their influencing factors were investigated and analyzed in detail through Fourier transform infrared spectroscopy (FTIR) and laser Raman spectra analysis. The TDC samples (0.7% < Ro,max <3.1%) were collected from Huaibei coalfield with different deformation mechanisms and intensity. The FTIR of TDCs shows that the metamorphism and the deformation affect the degradation and polycondensation process of macromolecular structure to different degree. The Raman spectra analysis indicates that secondary structure defects can be produced mainly by structural deformation, also the metamorphism influences the secondary structure defects and aromatic structure. Through comprehensive analysis, it was discussed that the ductile deformation could change to strain energy through the increase and accumulation of dislocation in molecular structure units of TDC, and it could make an obvious influence on degradation and polycondensation. While the brittle deformation could change to frictional heat energy and promote the metamorphism and degradation of TDC structure, but has less effect on polycondensation. Furthermore, degradation is the main reason for affecting the structural evolution of coal in lower metamorphic stage, and polycondensation is the most important controlling factor in higher metamorphic stage. Under metamorphism and deformation, the small molecules which break and fall off from the macromolecular tructure of TDC are preferentially replenished and embedded into the secondary structure defects or the residual aromatic rings were formed into aromatic structure by polycondensation. This process improved the stability of coal structure. It is easier for ductile deformation of coal to induce the secondary structure defects than brittle deformation.

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