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1.
IEEE Trans Pattern Anal Mach Intell ; 45(8): 9339-9356, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37027611

RESUMEN

To alleviate the need for large-scale pixel-wise annotations, domain adaptation for semantic segmentation trains segmentation models on synthetic data (source) with computer-generated annotations, which can be then generalized to segment realistic images (target). Recently, self-supervised learning (SSL) with a combination of image-to-image translation shows great effectiveness in adaptive segmentation. The most common practice is to perform SSL along with image translation to well align a single domain (source or target). However, in this single-domain paradigm, unavoidable visual inconsistency raised by image translation may affect subsequent learning. In addition, pseudo labels generated by a single segmentation model aligned in either the source or target domain may be not accurate enough for SSL. In this paper, based on the observation that domain adaptation frameworks performed in the source and target domain are almost complementary, we propose a novel adaptive dual path learning (ADPL) framework to alleviate visual inconsistency and promote pseudo-labeling by introducing two interactive single-domain adaptation paths aligned in source and target domain respectively. To fully explore the potential of this dual-path design, novel technologies such as dual path image translation (DPIT), dual path adaptive segmentation (DPAS), dual path pseudo label generation (DPPLG) and Adaptive ClassMix are proposed. The inference of ADPL is extremely simple, only one segmentation model in the target domain is employed. Our ADPL outperforms the state-of-the-art methods by large margins on GTA5 →Cityscapes, SYNTHIA → Cityscapes and GTA5 →BDD100K scenarios. Code and models are available at https://github.com/royee182/DPL.


Asunto(s)
Semántica , Procesamiento de Imagen Asistido por Computador , Algoritmos
2.
Lancet Infect Dis ; 22(10): 1484-1492, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35868342

RESUMEN

BACKGROUND: China has low seasonal influenza vaccination rates among priority populations. In this study, we aimed to evaluate a pay-it-forward strategy to increase influenza vaccine uptake in rural, suburban, and urban settings in China. METHODS: We performed a quasi-experimental pragmatic trial to examine the effectiveness of a pay-it-forward intervention (a free influenza vaccine and an opportunity to donate financially to support vaccination of other individuals) to increase influenza vaccine uptake compared with standard-of-care user-paid vaccination among children (aged between 6 months and 8 years) and older people (≥60 years) in China. Recruitment took place in the standard-of-care group until the expected sample size was reached and then in the pay-it-forward group in primary care clinics from a rural site (Yangshan), a suburban site (Zengcheng), and an urban site (Tianhe). Participants were introduced to the influenza vaccine by project staff using a pamphlet about influenza vaccination and were either asked to pay out-of-pocket at the standard market price (US$8·5-23·2; standard-of-care group) or to donate any amount anonymously (pay-it-forward group). Participants had to be eligible to receive an influenza vaccine and to have not received an influenza vaccine in the past year. The primary outcome was vaccine uptake. Secondary outcomes were vaccine confidence and costs (from the health-care provider perspective). Regression methods compared influenza vaccine uptake and vaccine confidence between the two groups. This trial is registered with ChiCTR, ChiCTR2000040048. FINDINGS: From Sept 21, 2020, to March 3, 2021, 300 enrolees were recruited from patients visiting three primary care clinics. 55 (37%) of 150 people in the standard-of-care group (40 [53%] of 75 children and 15 [20%] of 75 older adults) and 111 (74%) of 150 in the pay-it-forward group (66 [88%] of 75 children and 45 [60%] of 75 older adults) received an influenza vaccine. People in the pay-it-forward group were more likely to receive an influenza vaccine compared with those in the standard-of-care group (adjusted odds ratio [aOR] 6·7 [95% CI 2·7-16·6] among children and 5·0 [2·3-10·8] among older adults). People in the pay-it-forward group had greater confidence in vaccine safety (aOR 2·2 [95% CI 1·2-3·9]), importance (3·1 [1·6-5·9]), and effectiveness (3·1 [1·7-5·7]). In the pay-it-forward group, 107 (96%) of 111 participants donated money for subsequent vaccinations. The pay-it-forward group had a lower economic cost (calculated as the cost without subtraction of donations) per person vaccinated (US$45·60) than did the standard-of-care group ($64·67). INTERPRETATION: The pay-it-forward intervention seemed to be effective in improving influenza vaccine uptake and community engagement. Our data have implications for prosocial interventions to enhance influenza vaccine uptake in countries where influenza vaccines are available for a fee. FUNDING: Bill & Melinda Gates Foundation and the UK National Institute for Health Research.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Anciano , Niño , China , Humanos , Lactante , Gripe Humana/prevención & control , Oportunidad Relativa , Vacunación
3.
J Phys Chem Lett ; 13(19): 4297-4308, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35532545

RESUMEN

Molecular cross-scale gridization and polygridization of organic π-backbones make it possible to install 0/1/2/3-dimensional organic wide-bandgap semiconductors (OWBGSs) with potentially ZnO-like fascinating multifunctionality such as optoelectronic and piezoelectronic features. However, gridization effects are limited to uncover, because the establishment of gridochemistry still requires a long time, which offers a chance to understand the effects with a theoretical method, together with data statistics and machine learning. Herein, we demonstrate a state-of-the-art 3D cubic nanogridon with a size of ∼2 × 2 × 1.5 nm3 to examine its multigridization of π-segments on the bandgap, molecular strain energy (MSE), as well as reorganization energy (ROE). A cubic gridon (CG) consists of a four-armed bifluorene skeleton and a thiophene-containing fused arene plane with the Csp3 spiro-linkage, which can be deinstalled into face-on or edge-on monogrids. As a result, multigridization does not significantly reduce bandgaps (Eg ≥ 4.03 eV), while the MSE increases gradually from 4.72 to 23.83 kcal/mol. Very importantly, the ROE of a CG exhibits an extreme reduction down to ∼28 meV (λ+) that is near the thermal fluctuation energy (∼26 meV). Our multigridization results break through the limitation of the basic positively proportional relationship between reorganization energies and bandgaps in organic semiconductors. Furthermore, multigridization makes it possible to keep the ROE small under the condition of a high MSE in OWBGS that will guide the cross-scale design of multifunctional OWBGSs with both inorganics' optoelectronic performance and organics' mechanical flexibility.

4.
Artículo en Inglés | MEDLINE | ID: mdl-33048674

RESUMEN

Our impression about one person often updates after we see more aspects of him/her and this process keeps iterating given more meetings. We formulate such an intuition into the problem of person re-identification (re-ID), where the representation of a query (probe) image is iteratively updated with new information from the candidates in the gallery. Specifically, we propose a simple attentional aggregation formulation to instantiate this idea and showcase that such a pipeline achieves competitive performance on standard benchmarks including CUHK03, Market-1501 and DukeMTMC. Not only does such a simple method improve the performance of the baseline models, it also achieves comparable performance with latest advanced re-ranking methods. Another advantage of this proposal is its flexibility to incorporate different representations and similarity metrics. By utilizing stronger representations and metrics, we further demonstrate state-of-the-art person re-ID performance, which also validates the general applicability of the proposed method.

5.
Se Pu ; 38(3): 341-349, 2020 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-34213214

RESUMEN

Seven kinds of amino bonded silica gels were prepared. They were aminopropyl bonded silica gel (SiO2-N), ethylenediamine-N-propyl bonded silica gel (SiO2-2N), diethylenetriamine bonded silica gel (SiO2-3N), triethylenetetramine bonded silica gel (SiO2-4N), tetraethylene pentamine bonded silica gel (SiO2-5N), pentaethylene hexamine bonded silica gel (SiO2-6N) and polyvinylimide bonded silica gel (SiO2-nN). The densities of the bonded amino groups in SiO2-N and SiO2-2N prepared by a one-step method were up to 2.07mmol/g and 1.71mmol/g, respectively. The density of the bonded amino groups in SiO2-nN with ethylene imine units prepared by a two-step method, was 0.02mmol/g. The densities of the bonded amino groups in the other silica gels were similar, about 0.50mmol/g. The synthesized silica gels were used to investigate the adsorption of the heavy metal ion Pb2+ which commonly exists in aqueous solutions. About 20 mg of the silica gel was added to 10 mL of 400 mg/L Pb2+, at pH 5 and 30℃. The results indicated that the adsorption capacity reached the maximum value after 10 h. The adsorption process was fit to the Freundlich isothermal equation. The adsorption capacities of SiO2-N, SiO2-2N, SiO2-3N, SiO2-4N, SiO2-5N, SiO2-6N and SiO2-nN to Pb2+were 131.28, 138.98, 85.37, 75.22, 61.87, 79.12 and 114.06 mg/g, respectively, indicating the potential utility of these amino-functionalized silica gels for the adsorption of Pb2+.

6.
Se Pu ; 30(8): 798-803, 2012 Aug.
Artículo en Chino | MEDLINE | ID: mdl-23256382

RESUMEN

A rapid and special supported liquid-liquid extraction (SLE) column was developed with a composite diatomite material. The SLE column was evaluated by high performance liquid chromatography (HPLC) with acidic, neutral and alkaline compounds dissolved in water. Furthermore, some real complex samples were also analyzed by HPLC with the SLE method. The recoveries of benzoic acid (acidic), p-nitroaniline (alkaline) and 4-hydroxy-benzoic methyl ester (neutral) treated by the SLE column were 90.6%, 98.1% and 97.7%. However, the recoveries of the three compounds treated by traditional liquid-liquid extraction (LLE) method were 71.9%, 81.9% and 83.9%. The results showed that the SLE technique had higher recoveries than the traditional LLE method. The spiked recoveries of the complex samples, such as benzoic acid in Sprite and dexamethasone acetate, chlorphenamine maleate, indomethacin in bovine serum, were between 80% and 110% and the relative standard deviations (RSDs) were less than 15%. For biological specimen, the results could be accepted. Meantime, many disadvantages associated with traditional LLE method, such as emulsion formation, didn't occur using SLE column. The SLE column technique is a good sample preparation method with many advantages, such as rapid, simple, robust, easily automated, high recovery and high-throughput, which would be widely used in the future.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Tierra de Diatomeas/química , Extracción Líquido-Líquido/métodos , Compuestos de Anilina/análisis , Compuestos de Anilina/aislamiento & purificación , Ácido Benzoico/análisis , Ácido Benzoico/aislamiento & purificación , Dexametasona/análogos & derivados , Dexametasona/análisis , Dexametasona/aislamiento & purificación , Indometacina/análisis , Indometacina/aislamiento & purificación
7.
Chin Med J (Engl) ; 125(5): 786-93, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22490576

RESUMEN

BACKGROUND: Astragalus polysaccharides (APS), the main active extract from Astragalus membranaceus (a traditional Chinese medicinal herb), is associated with a variety of immunomodulatory activities. The purpose of the present study was to examine the effect of APS on the function of Treg cells in the tumor microenvironment of human hepatocellular carcinoma (HCC) and to identify the pharmacologic mechanism of APS responsible for the anti-chemotactic activity in CD4+CD25highTreg cells in tumor site of HCC. METHODS: The prevalence of Treg in fresh tissue samples from 31 patients with HCC after radicalhepatectomy was detected. CD4, CD25 and CD127 were selected as Treg cell makers to phenotype cell populations. The expression of FOXp3 mRNA was also analyzed. The migration and proliferation of Treg cells were observed. Interleukin (IL)-4, IL-10, IFN-γ and SDF-1 in cell supernatant were detected. For all tests, functions of Treg cells were evaluated after treatment with APS. RESULTS: APS can inhibit the growth and proliferation of CD4+CD25+Treg cells in vitro in a dose- and time-dependent manner. APS may inhibit CD4+CD25+Treg cells through restoring the cytokine imbalance and reducing the expression of FOXp3 in local HCC microenvironments. SDF-1 played an important role in there recruitment of Treg cells into the tumor microenvironment of HCC. APS might have inhibiting effects on Treg cell migration by blocking SDF-1 or its receptor through the CXCR4/CXCL12 pathway. CONCLUSIONS: The increase in numbers of tumor associated Treg cells might play a role in modulation of the immune response against HCC. APS can restore the cytokine balance in the tumor micro environment and suppress the expression of FOXp3 mRNA to inhibit the immune suppressive effects of Treg cells. The application of APS in the tumor microenvironment might act to enhance the anti-tumor effects of the immunotherapy-based methods, and consequently to increase the survival rate in HCC.


Asunto(s)
Planta del Astrágalo/química , Linfocitos T CD4-Positivos/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Neoplasias Hepáticas/metabolismo , Polisacáridos/farmacología , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Carcinoma Hepatocelular/inmunología , Línea Celular , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Neoplasias Hepáticas/inmunología
8.
Chin Med J (Engl) ; 122(24): 3020-4, 2009 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-20137495

RESUMEN

BACKGROUND: It has been found that the expression of cystic fibrosis transmembrane conductance regulator (CFTR) is closely related to allergic rhinitis (AR). In the previous study, we have demonstrated that antiallergic herbal agents (AHA) can obviously inhibit the allergic reaction of AR. The aim of this study was to explore the expression of CFTR and the effects of AHA on CFTR to improve the allergic reaction of AR. METHODS: An animal model of an AR rabbit was established using ovalbumin (OVA). The rhinitis rabbits were randomly assigned to three groups: AHA treating group (AHATG), modeling group (MG) and healthy controlling group (HCG). The expressions of CFTR protein were examined by immunohistochemical method. The mucosal epithelial cells of all the rabbits were primarily cultured with tissue culture method in vitro and treated with or without glibenclamide for 24 hours. The levels of monocyte chemotactic factor-1 (MCP-1) and RANTES protein in supernatants of culture were measured by ELISA, and the expressions of CFTR mRNA were detected by real-time PCR. RESULTS: The expressions of CFTR mRNA and protein greatly increased in mucosal epithelial cells of MG. The protein concentrations of MCP-1, RANTES in culture supernatants of MG were significantly higher than those in the other two groups (P < 0.01), and they reached much higher level than those at the start points in the MG (P < 0.05) and were significantly different compared with those in the AHATG after being cultured for 24 hours (P < 0.01). CFTR mRNA in MG + glibenclamide were much lower than those in MG (P < 0.05). RANTES and CFTR mRNA treated with glibenclamide in AHATG were significantly lower than those in the AHATG (P < 0.01). Minimal changes in the secretions of MCP-1 in the epithelial cells were detected between AHATG and AHATG + glibenclamide (P > 0.05). CONCLUSIONS: AHA can inhibit the secretions of CFTR, RANTES and MCP-1 in mucosal epithelia and improve inflammatory reaction of AR. CFTR may play an important role in the secretion of RANTES and mucosal inflammatory response in AR. Glibenclamide can inhibit the CFTR secretion in mucosal epithelial cells, in particular during AR process. These effects of glibenclamide on secretion of RANTES can be effectively strengthened by AHA.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Medicamentos Herbarios Chinos/uso terapéutico , Membrana Mucosa/metabolismo , Mucosa Nasal/metabolismo , Rinitis Alérgica Estacional/tratamiento farmacológico , Rinitis Alérgica Estacional/metabolismo , Animales , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Ensayo de Inmunoadsorción Enzimática , Gliburida/farmacología , Gliburida/uso terapéutico , Inmunohistoquímica , Masculino , Membrana Mucosa/efectos de los fármacos , Mucosa Nasal/efectos de los fármacos , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , Conejos , Distribución Aleatoria
9.
Se Pu ; 24(1): 46-8, 2006 Jan.
Artículo en Chino | MEDLINE | ID: mdl-16827310

RESUMEN

Teicoplanin-bonded chiral stationary phase was prepared and used for the direct chiral separation of racemic pantoprazole sodium by reversed-phase high performance liquid chromatography (HPLC). The influences of organic modifiers, the composition of mobile phase, the flow rate and column temperature on enantioseparation were studied. It was found that methanol was preferred than acetonitrile when used as organic modifier. With the increase of column temperature, chiral solutes were less retained and the separation factor value decreased indicating that lower temperature was better for the enantioseparation. Better resolution was obtained at lower flow rates as a result of minimization of the resistance of mass transfer. Based on these experimental data, the chiral HPLC method for the analysis of pantoprazole sodium on prepared chiral column (150 mm x 4.6 mm i. d., 5 microm) was established with simplicity and good reproducibility, by using methanol-water (35 : 65, v/v) as mobile phase at a flow rate of 0.6 mL/min and 20 degrees C.


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Estereoisomerismo , Teicoplanina/química , Acetonitrilos/química , Pantoprazol
10.
Se Pu ; 24(6): 566-9, 2006 Nov.
Artículo en Chino | MEDLINE | ID: mdl-17288134

RESUMEN

A novel method was developed to determine the content of chlorhexidine acetate (CA) in chlorhexidine acetate suppositories by high performance liquid chromatography (HPLC) coupled with hollow fiber membrane solvent microextraction. The sample was extracted with 1.5 mol/L acetic acid solution five times, then a hollow fiber containing n-octanol was placed in the sample solution to perform microextraction for extracting 20 min. The extract was analyzed by HPLC with UV detection at 260 nm. The chromatographic conditions were as following: acetonitrile-redistilled water (29:71, v/v, containing 0.3% triethylamine, pH 3.0) as mobile phase with the flow rate of 1 mL/min. The calibration curve of CA was linear from 0.5 to 16 mg/L. The method recovery was over 98.0% with relative standard deviation less than 4.0%. By using hollow fiber membrane solvent microextraction, the enrichment of 24-fold was achieved. The method is specific, simple, fast, sensitive and suitable for the determination of chlorhexidine acetate.


Asunto(s)
Clorhexidina/análisis , Métodos Analíticos de la Preparación de la Muestra , Cromatografía Líquida de Alta Presión , Membranas Artificiales , Solventes , Supositorios
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