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1.
Anal Chim Acta ; 1178: 338849, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482875

RESUMO

Various mesoporous adsorbents are of great promise for enriching small molecules from biological samples based on the size-exclusion effect. At present, the mesoporous adsorbents have adsorption sites distributed uniformly on the internal and external surfaces of mesopores. However, the adsorption sites on the external surface can adsorb proteins, interfering with the enrichment of small molecules. Herein, a novel immobilized-Ti4+ magnetic mesoporous adsorbent removing the adsorption sites on the external surface was facile prepared via the coupling chemistry of isocyanate with amine and consequent hydrolysis of urea linkage by urease. The adsorbent enables fast and selective enrichment of phosphopeptides and nucleotides from biological samples. In addition, sensitive detection methods for phosphopeptides and nucleotides in human serum are developed by coupling the magnetic solid-phase extraction with matrix-assisted laser desorption/ionization time of flight mass spectrometry and liquid chromatography-mass spectrometer, respectively. Under optimal conditions, response is linear (R2 ≥ 0.9923), limits of detection are low (0.41-9.48 ng mL-1), and reproducibility is acceptable (inter- and intra-day assay RSDs of≤15.0%) for six nucleotides. The developed strategy offers an effective method to eliminate the interference of proteins in the enrichment of small molecules from real biological samples.


Assuntos
Nucleotídeos , Fosfopeptídeos , Adsorção , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
2.
Front Oncol ; 11: 687430, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211854

RESUMO

Background: CD38 belongs to the ribosyl cyclase family and is expressed on various hematological cells and involved in immunosuppression and tumor promotion. Although targeting CD38 antibodies has been approved for treatment of multiple myeloma, the function of CD38 in solid tumor, oral squamous cell carcinoma (OSCC) etc., has not been investigated. Methods: This retrospective study included 92 OSCC samples and analyzed the spatial distribution of CD38 by immunohistochemistry (IHC). The values of diagnosis and prognosis of CD38 were evaluated. Additionally, 53 OSCC preoperative peripheral blood samples were used to be analyzed by flow cytometry. Tumor Immune Estimation Resource (TIMER) and cBioPortal databases were used to study CD38 level in various tumors and its correlation with tumor immune microenvironment in head and neck squamous cell carcinoma (HNSCC). Results: CD38 ubiquitously presented in tumor cells (TCs), fibroblast-like cells (FLCs), and tumor-infiltrating lymphocytes (TILs). Patients with highly expressed CD38 in TCs (CD38TCs) had higher TNM stage and risk of lymph node metastasis. Upregulation of CD38 in FLCs (CD38FLCs) was significantly associated with poor WPOI. Escalated CD38 in TILs (CD38TILs) led to higher Ki-67 level of tumor cells. Moreover, patients with enhanced CD38TCs were susceptible to postoperative metastasis occurrence, and those with highly expressed CD38TILs independently predicted shorter overall and disease-free survival. Strikingly, patients with highly expressed CD38TILs, but not CD38TCs and CD38FLCs, had significantly lower CD3+CD4+ T cells and higher ratio of CD3-CD16+CD56+NK cells. The imbalance of immune system is attributed to dysregulated immune checkpoint molecules (VISTA, PD-1, LAG-3, CTLA-4, TIGIT, GITR) as well as particular immune cell subsets, which were positively correlated with CD38 expression in HNSCC. Conclusion: CD38 is a poor prognostic biomarker for OSCC patients and plays a vital role in governing immune microenvironment and circulating lymphocyte homeostasis. Co-expression between CD38 and immune checkpoint molecules provides new insight into immune checkpoint therapy.

3.
Opt Express ; 29(2): 797-804, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726308

RESUMO

In this paper, an optofluidic phase modulator based on electrowetting is presented. The modulator consists of an inner and outer chamber. Two immiscible liquids are filled into the chambers, and a transparent sheet is fixed between the liquid-liquid interface to obtain a flat interface. By applying different voltages to the modulator, the flat interface moves up and down leading to the change of optical path length. Consequently, the variation of the optical path in the proposed modulator exploits the ability to alter the optical phase. To prove the concept, a prototype of the phase modulator is fabricated in experiment, and the ability of phase modulation is detected. Our proposed modulator performs optical phase shift up to ∼6.68 π driven with 150 V. Widespread applications of such an optofluidic phase modulator is foreseeable.

4.
IEEE Trans Pattern Anal Mach Intell ; 42(5): 1176-1190, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30640599

RESUMO

Corners are popular features for relative pose computation with 2D-2D point correspondences. Stable corners may be formed by two 3D rays sharing a common starting point. We call such elements ray-point-ray (RPR) structures. Besides a local invariant keypoint given by the lines' intersection, their reprojection also defines a corner orientation and an inscribed angle in the image plane. The present paper investigates such RPR features, and aims at answering the fundamental question of what additional constraints can be formed from correspondences between RPR features in two views. In particular, we show that knowing the value of the inscribed angle between the two 3D rays poses additional constraints on the relative orientation. Using the latter enables the solution of the relative pose problem with as few as 3 correspondences across the two images. We provide a detailed analysis of all minimal cases distinguishing between 90-degree RPR-structures and structures with an arbitrary, known inscribed angle. We furthermore investigate the special cases of a known directional correspondence and planar motion, the latter being solvable with only a single RPR correspondence. We complete the exposition by outlining an image processing technique for robust RPR-feature extraction. Our results suggest high practicality in man-made environments, where 90-degree RPR-structures naturally occur.

5.
J Chromatogr A ; 1607: 460401, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31376983

RESUMO

Boronate affinity is an important method for the enrichment and separation of cis-diol containing compounds, but most of the conventional boronate materials suffer from weak binding strength as well as low binding capacity towards glycoproteins due to the use of single boronic acids as ligands. In this work, a novel multidentate boronate magnetic adsorbent was assembled by using amined polyhedral oligomeric silsesquioxane as spacer and a diboronic acid as ligand. The specially designed adsorbent exhibited high adsorption capacity for cis-diols due to the high density of phenylbronic acid moieties. More interestingly, the dissociation constants toward glycoproteins on the material were lowered to be ∼10-6 M, being at least 3 orders lower than the single boronic acid bonded adsorbents. By comparing the binding properties of small molecules containing one and two pairs of cis-diols, the enhanced binding strength of glycoproteins on the multidentate boronate magnetic adsorbent was attributed to the synergistic binding of glycoproteins on the special interface. The new materials successfully captured glycoproteins from 1000-fold diluted egg white, suggesting that the material could be an optional alternative adsorbent for enriching trace glycoproteins from complex bio-samples.


Assuntos
Ácidos Borônicos/química , Glicoproteínas/química , Fenômenos Magnéticos , Compostos de Organossilício/química , Adenosina/análise , Adsorção , Animais , Galinhas , Cinamatos/análise , Depsídeos/análise , Cinética , Ligantes , Temperatura
6.
Langmuir ; 34(36): 10569-10579, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30111117

RESUMO

Graphene oxide (GO) has been demonstrated as the most promising candidate for surface modification of polymer separation membranes for durable filtration applications. However, the adhesion between GO coating and polymer substrate, as the most essential issue for reliable applications, has been little explored. Herein, we developed a facile high-pressure assisted deposition method to physically anchor GO sheets on microfiltration (MF) and reverse osmosis (RO) membranes, and established a tape test procedure for assessing the adhesion of GO coating to polymer substrates based on the ASTM D3359. Through regulating the GO sources and coating process, we demonstrated that the adhesion depends sensitively on the GO flake size and deposition pressure, whereas the adhesion level dramatically improved from 0B to 5B, with decrease in the lateral size of GO and increase in the coating deposition pressure. The strong GO coatings showed evidently higher water flux than that of weak counterparts. The underlying mechanism was further analyzed and verified. Nanosize of GO and high deposition pressure favor the formation of the conformal morphologies of GO coatings on both MF and RO membranes, which allow strong interfacial van der Waals interaction because of the large contact areas and result in the strong GO coatings on membranes. These results potentially open up a versatile pathway to develop the strong graphene-based coatings on separation membranes.

7.
Sensors (Basel) ; 18(4)2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29642648

RESUMO

To address the problem of estimating camera trajectory and to build a structural three-dimensional (3D) map based on inertial measurements and visual observations, this paper proposes point-line visual-inertial odometry (PL-VIO), a tightly-coupled monocular visual-inertial odometry system exploiting both point and line features. Compared with point features, lines provide significantly more geometrical structure information on the environment. To obtain both computation simplicity and representational compactness of a 3D spatial line, Plücker coordinates and orthonormal representation for the line are employed. To tightly and efficiently fuse the information from inertial measurement units (IMUs) and visual sensors, we optimize the states by minimizing a cost function which combines the pre-integrated IMU error term together with the point and line re-projection error terms in a sliding window optimization framework. The experiments evaluated on public datasets demonstrate that the PL-VIO method that combines point and line features outperforms several state-of-the-art VIO systems which use point features only.

8.
Chem Soc Rev ; 46(23): 7469, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-29098211

RESUMO

Correction for 'The physics and chemistry of graphene-on-surfaces' by Guoke Zhao, Xinming Li, Meirong Huang et al., Chem. Soc. Rev., 2017, 46, 4417-4449.

9.
Chem Soc Rev ; 46(15): 4417-4449, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28678225

RESUMO

Graphene has demonstrated great potential in next-generation electronics due to its unique two-dimensional structure and properties including a zero-gap band structure, high electron mobility, and high electrical and thermal conductivity. The integration of atom-thick graphene into a device always involves its interaction with a supporting substrate by van der Waals forces and other intermolecular forces or even covalent bonding, and this is critical to its real applications. Graphene films on different surfaces are expected to exhibit significant differences in their properties, which lead to changes in their morphology, electronic structure, surface chemistry/physics, and surface/interface states. Therefore, a thorough understanding of the surface/interface properties is of great importance. In this review, we describe the major "graphene-on-surface" structures and examine the roles of their properties and related phenomena in governing the overall performance for specific applications including optoelectronics, surface catalysis, anti-friction and superlubricity, and coatings and composites. Finally, perspectives on the opportunities and challenges of graphene-on-surface systems are discussed.

10.
Wei Sheng Yan Jiu ; 46(6): 861-867, 2017 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-29903192

RESUMO

OBJECTIVE: To study the differences in food consumption among rural residents in various regions of China, and to analyze the climatic factors that affect the food consumption of rural residents. METHODS: Based on the consumption data of 13 kinds of food of rural residents including wheat, rice, other grain, fresh vegetables, pork, beef and mutton, poultry, eggs and related products, milk and related products, aquatic products, edible oil, sugar and liquor collected from the China Statistical Yearbook and China's Economic and social data research platform during 2000 to 2012, cluster analysis was conducted to partition the dietary structure and compare the differences in food consumption in each geographical area. Selecting the average temperature, annual temperature difference, daily temperature difference, average air pressure, average daily precipitation, average wind speed, average relative humidity, average sunshine duration, 8 climatic factors as independent variables from the "Dataset of daily surface observations values in individual years( 1981-2010) in China "and "Dataset of annual values of climate data from Chinese surface stations for global exchange " released by China Meteorological Data Service Center to establish a multivariate linear regression model to study the correlation between food consumption and climate. RESULTS: The geographical partition of dietary structure of rural residents in China was as follows: Beijing-Tianjin region, northeast region, upstream and downstream parts of the Yellow River region, southeast coastal area, the part middle and lower reaches of the Yangtze River region, Lingnan area, southwest region, Inner Mongolia, Tibet, Qing-Xin( Qinghai and Xinjiang)region. In the comparison of annual per capita food consumption in various regions: the consumption of eggs and related products( 12. 96 kg) and edible oil( 10. 18 kg) in BeijingTianjin region, vegetable( 128. 20 kg) in northeastern region, aquatic products( 15. 81 kg) and liquor( 19. 04 kg) in the southeastern coastal areas, rice( 189. 36 kg) and poultry( 10. 17 kg) in Lingnan area, pork( 26. 46 kg) in southwest China, other food( 126. 31 kg), milk and related products( 32. 38 kg), beef and mutton( 12. 87 kg) and sugar( 2. 65 kg) in Tibet, and wheat( 184. 63 kg) in Qingxin region was the highest in China. While the consumption of sugar( 0. 79 kg) in northeastern region, other food( 10. 64 kg) in the southeastern coastal areas, wheat( 0. 60 kg) and milk and related products( 0. 33 kg) in Lingnan area, beef and mutton( 0. 43 kg) in southwest China, edible oil( 4. 21 kg) in Inner Mongolia, vegetables( 19. 21 kg), eggs and related products( 0. 60 kg), aquatic products( 0. 01 kg), pork( 2. 23 kg) and poultry( 0. 03 kg) in Tibet, and rice( 13. 00 kg)and liquor( 2. 25 kg) in Qing-Xin regions was the lowest in China. The result of multiple linear regression analysis of climate and food consumption showed that consumption of wheat in staple foods was negatively correlated with average daily precipitation( P < 0. 01, Adj. R~2= 0. 632); and there was a positive correlation between rice consumption and average daily precipitation, and a negative correlation with average temperature and daily temperature difference( P < 0. 01, Adj. R~2= 0. 839). There was a positive correlation between vegetable consumption and annual temperature difference, and negative correlation with average sunshine duration( P < 0. 01, Adj. R~2= 0. 450). The pork consumption was negatively correlated with the average sunshine duration( P < 0. 01, Adj. R~2= 0. 386). CONCLUSION: The dietary structure of rural residents in China can bedivided into 10 kinds of geographical partitions. Average daily precipitation is negatively and positively correlated with consumption of wheat and rice, respectively. Average sunshine duration has negative impact on vegetable and pork consumption. Average temperature and daily temperature difference are negatively correlated with rice consumption. And annual temperature difference has positive impact on vegetable consumption.


Assuntos
Clima , Dieta , Alimentos , População Rural , Pequim , China , Humanos , Tibet , Verduras
11.
ACS Nano ; 9(11): 10867-75, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26468735

RESUMO

Nanomaterials serve as promising candidates for strain sensing due to unique electromechanical properties by appropriately assembling and tailoring their configurations. Through the crisscross interlacing of graphene microribbons in an over-and-under fashion, the obtained graphene woven fabric (GWF) indicates a good trade-off between sensitivity and stretchability compared with those in previous studies. In this work, the function of woven fabrics for highly sensitive strain sensing is investigated, although network configuration is always a strategy to retain resistance stability. The experimental and simulation results indicate that the ultrahigh mechanosensitivity with gauge factors of 500 under 2% strain is attributed to the macro-woven-fabric geometrical conformation of graphene, which induces a large interfacial resistance between the interlaced ribbons and the formation of microscale-controllable, locally oriented zigzag cracks near the crossover location, both of which have a synergistic effect on improving sensitivity. Meanwhile, the stretchability of the GWF could be tailored to as high as over 40% strain by adjusting graphene growth parameters and adopting oblique angle direction stretching simultaneously. We also demonstrate that sensors based on GWFs are applicable to human motion detection, sound signal acquisition, and spatially resolved monitoring of external stress distribution.


Assuntos
Eletrônica/métodos , Grafite/química , Nanotecnologia/métodos , Pele/metabolismo , Têxteis , Tato , Adesividade , Humanos , Polímeros/química
12.
Nanoscale ; 7(18): 8398-404, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25876755

RESUMO

Hydrogen plays a crucial role in the chemical vapor deposition (CVD) growth of graphene. Here, we have revealed the roles of hydrogen in the two-step CVD growth of MoS2. Our study demonstrates that hydrogen acts as the following: (i) an inhibitor of the thermal-induced etching effect in the continuous film growth process; and (ii) a promoter of the desulfurization reaction by decreasing the S/Mo atomic ratio and the oxidation reaction of the obtained MoSx (0 < x < 2) films. A high hydrogen content of more than 100% in argon forms nano-sized circle-like defects and damages the continuity and uniformity of the film. Continuous MoS2 films with a high crystallinity and a nearly perfect S/Mo atomic ratio were finally obtained after sulfurization annealing with a hydrogen content in the range of 20%-80%. This insightful understanding reveals the crucial roles of hydrogen in the CVD growth of MoS2 and paves the way for the controllable synthesis of two-dimensional materials.

13.
Nanoscale ; 7(16): 7318-22, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25821068

RESUMO

We report the design and preparation of graphene and polyaniline (PANI) woven-fabric composite films by in situ electropolymerization. The introduction of PANI greatly improves the electrochemical properties of solid-state supercapacitors which possess capacitances as high as 23 mF cm(-2), and exhibit excellent cycling stability with ∼ 100% capacitance retention after 2000 cycles. The devices have displayed superior flexibility with improved areal specific capacitances to 118% during deformation.

14.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 39(9): 907-11, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25269498

RESUMO

OBJECTIVE: To explore the factors related to the length of hospital stay for cerebrovascular accident and to provide the basis for health administrative department to formulate measures, and for clinical department to develop treatment guidelines. METHODS: We collected the medical record of the hospitalized cerebrovascular accident patients from 2008 to 2013 in the Third Xiangya Hospital, Central South University. The collected data included demographic information, disease characteristics, treatment information and health economics information. Then we analyzed the factors related to the length of hospital stay for cerebrovascular accident. SPSS 13.0 was used for statistical analysis and logistic regression and nonparametric rank sum test was performed. RESULTS: The length of stay in hospital was from one day to 513 days, with a median of 10 days. The length of stay for women was shorter than that of men (OR=0.869). The length of stay for the older patients was longer than that of younger patients (OR=1.158). The length of stay for patients who implemented a surgery was 1.686 times longer than those who were not implemented a surgery (OR=1.686). The length of stay for ischemic cerebrovascular patients was shorter than that of the hemorrhagic cerebrovascular patients (OR=0.275). The patients with new rural cooperative medical insurance or without health insurance usually stayed a short time in hospital. CONCLUSION: Sex, age, surgery, type of cerebrovascular accident and medicare type are the factors that affect the length of hospital stay for cerebrovascular accident.


Assuntos
Tempo de Internação , Acidente Vascular Cerebral , Feminino , Humanos , Modelos Logísticos , Masculino
16.
J Hazard Mater ; 252-253: 250-7, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23542320

RESUMO

A pilot-scale deep shaft aeration bioreactor (DSAB) with 110 m in depth and 0.5m in diameter for the pretreatment of landfill leachate in winter was operated at a daily treatment scale of around 10-20 tons. It was found that the performance of the DSAB mainly depended on the inflow loads and concentrations of pollutants. NH3-N, TN, COD, TOC removals of 66-94%, 41-64%, 67-87%, 55-92% at organic load rate of 1.7-9.4 g CODL(-1)day(-1) and hydraulic retention time of 1-2d were obtained using DSAB, respectively, with the lowest ambient temperature of -3 °C. The effluent COD can be reduced to below 1000 mg/L, an acceptable level for advanced treatment using reverse osmosis system, when the influent COD was below 7000 mg/L at 10t/d. The EEM and GPC analysis implied that the non-biodegradable contaminants such as humic- and fulvic-like DOM dominated in the organic fractions of the effluent, which rendered the biological treatment ineffective. Compared with 20-40% removals obtained using traditional biological processes below 15 °C, DSAB showed a higher treatment efficiency for COD and NH3-N, even though at adverse conditions of poor carbon source, lower C/N ratio and high nitrite concentrations in the leachate of test.


Assuntos
Reatores Biológicos , Poluentes Químicos da Água/metabolismo , Aerobiose , Amônia/metabolismo , Bactérias/metabolismo , Benzopiranos/metabolismo , Análise da Demanda Biológica de Oxigênio , Carbono/análise , Temperatura Baixa , Substâncias Húmicas , Nitratos/metabolismo , Nitritos/metabolismo , Eliminação de Resíduos , Estações do Ano
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