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1.
Front Oncol ; 10: 909, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850304

RESUMO

Objective: The stage, size, grade, and necrosis (SSIGN) score can facilitate the assessment of tumor aggressiveness and the personal management for patients with clear cell renal cell carcinoma (ccRCC). However, this score is only available after the postoperative pathological evaluation. The aim of this study was to develop and validate a CT radiomic signature for the preoperative prediction of SSIGN risk groups in patients with ccRCC in multicenters. Methods: In total, 330 patients with ccRCC from three centers were classified into the training, external validation 1, and external validation 2 cohorts. Through consistent analysis and the least absolute shrinkage and selection operator, a radiomic signature was developed to predict the SSIGN low-risk group (scores 0-3) and intermediate- to high-risk group (score ≥ 4). An image feature model was developed according to the independent image features, and a fusion model was constructed integrating the radiomic signature and the independent image features. Furthermore, the predictive performance of the above models for the SSIGN risk groups was evaluated with regard to their discrimination, calibration, and clinical usefulness. Results: A radiomic signature consisting of sixteen relevant features from the nephrographic phase CT images achieved a good calibration (all Hosmer-Lemeshow p > 0.05) and favorable prediction efficacy in the training cohort [area under the curve (AUC): 0.940, 95% confidence interval (CI): 0.884-0.973] and in the external validation cohorts (AUC: 0.876, 95% CI: 0.811-0.942; AUC: 0.928, 95% CI: 0.844-0.975, respectively). The radiomic signature performed better than the image feature model constructed by intra-tumoral vessels (all p < 0.05) and showed similar performance with the fusion model integrating radiomic signature and intra-tumoral vessels (all p > 0.05) in terms of the discrimination in all cohorts. Moreover, the decision curve analysis verified the clinical utility of the radiomic signature in both external cohorts. Conclusion: Radiomic signature could be used as a promising non-invasive tool to predict SSIGN risk groups and to facilitate preoperative clinical decision-making for patients with ccRCC.

2.
Front Oncol ; 10: 592, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547934

RESUMO

Objective: To develop and validate a radiomics nomogram for preoperative prediction of tumor necrosis in patients with clear cell renal cell carcinoma (ccRCC). Methods: In total, 132 patients with pathologically confirmed ccRCC in one hospital were enrolled as a training cohort, while 123 ccRCC patients from second hospital served as the independent validation cohort. Radiomic features were extracted from corticomedullary and nephrographic phase contrast-enhanced computed tomography (CT) images. A radiomics signature based on optimal features selected by consistency analysis and the least absolute shrinkage and selection operator was developed. An image features model was constructed based on independent image features according to visual assessment. By integrating the radiomics signature and independent image features, a radiomics nomograph was constructed. The predictive performance of the above models was evaluated using receiver operating characteristic (ROC) curve analysis. Furthermore, the nomogram was assessed using calibration curve and decision curve analysis. Results: Thirty-seven features were used to establish a radiomics signature, which demonstrated better predictive performance than did the image features model constructed using tumor size and intratumoral vessels in the training and validation cohorts (p <0.05). The radiomics nomogram demonstrated satisfactory discrimination in the training (area under the ROC curve [AUC] 0.93 [95% CI 0.87-0.96]) and validation (AUC 0.87 [95% CI 0.79-0.93]) cohorts and good calibration (Hosmer-Lemeshow p>0.05). Decision curve analysis verified that the radiomics nomogram had the best clinical utility compared with the other models. Conclusion: The radiomics nomogram developed in the present study is a promising tool to predict tumor necrosis and facilitate preoperative clinical decision-making for patients with ccRCC.

3.
Appl Opt ; 59(6): 1564-1568, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225660

RESUMO

In this paper, we report the fabrication and characterization of chalcogenide-based planar waveguides for possible applications in broadband light sources and/or biochemical sensing. ${{\rm Ge}_{11.5}}{{\rm As}_{24}}{{\rm Se}_{64.5}}$Ge11.5As24Se64.5 film as bottom cladding followed by another layer of ${{\rm As}_2}{{\rm Se}_3}$As2Se3 was deposited on a thermally oxidized silicon wafer using thermal evaporation, and the waveguides were patterned directly on the ${{\rm As}_2}{{\rm Se}_3}$As2Se3 layer by UV exposure followed by inductively coupled plasma dry etching. The device structure was optimized by using commercial software (COMSOL Multiphysics) based on complete vector finite components, and the fundamental mode of the waveguide was calculated. By optimizing the geometry of the waveguide, the zero dispersion wavelength was shifted to a short wavelength (at $\sim{2}.{3}\;\unicode{x00B5} {\rm m}$∼2.3µm), which facilitates supercontinuum generation with shorter wavelength pump source. The insertion loss of the rib waveguides with different widths was measured using the cut-back method, and the best propagation loss at 1550 nm was 1.4 dB/cm.

4.
Sci Rep ; 10(1): 2418, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051465

RESUMO

We conducted pot experiments to assess the bioavailability of cadmium (Cd) in contaminated rhizosphere soil and accumulation in rice organs in response to nitrogen (N) supply ((NH4)2SO4, NH4NO3, NH4Cl). The results showed that the concentration of bioavailable Cd in rice rhizosphere soil was (NH4)2SO4 treatment > NH4Cl treatment > NH4NO3 treatment at the same level of N application and growth period; the Cd concentration in rice roots was (NH4)2SO4 treatment > NH4NO3 treatment > NH4Cl treatment; and the Cd concentration in rice straw was NH4NO3 treatment > NH4Cl. The Cd concentration in rice roots, straws, and seeds at the maturity stage was (NH4)2SO4 treatment > NH4Cl treatment. With the same N fertilizer, excessive N promoted Cd accumulation in rice at later growth stages. This suggested that sulfate (SO42-) influenced Cd concentration in rice. NH4Cl application maintained a low Cd level in different rice organs with the same N level. This confirmed that NH4Cl is a safe N source for rice planting in polymetallic sulfide mining areas. The study concludes that appropriate NH4Cl levels for Cd-contaminated paddy soil with high-S-content could obtain rice grains with Cd concentrations below the food safety standards (0.2 or 0.4 mg·kg-1).


Assuntos
Cádmio/metabolismo , Nitrogênio/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Biotransformação , Cádmio/análise , Fertilizantes/análise , Mineração , Nitrogênio/análise , Oryza/crescimento & desenvolvimento , Rizosfera , Solo/química , Poluentes do Solo/análise , Sulfatos/análise , Sulfatos/metabolismo , Sulfetos/análise , Sulfetos/metabolismo
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117885, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31813719

RESUMO

It is well known that, the incorporation of halide will improve the optical properties of chalcogenide glasses with a broad transparent range. Here, we investigated the optical properties and structure of Ge-As-Se-I glasses in order to disclose the role of halogen iodine in the formation of chalcogenide glassy network. It was found that, refractive index, zero dispersion wavelength and glass transition temperature Tg decrease with increasing iodine contents, while the cut-off edge (λvis) in the shorter wavelength blue-shifts apparently, and the whole transmission range is expanded widely. The glasses show good chemical stability against moisture. The zero dispersion wavelength of the glasses can be decreased to 4.32 µm by iodine-doping. The evolution of Raman spectra of the glasses indicates that, there is no obvious peak of iodine in Ge-As-Se-I glasses and the dominated glassy network are still the (GeSe) heteropolar bonds.

6.
Opt Lett ; 44(22): 5545-5548, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730104

RESUMO

A novel low-loss selenium-based chalcohalide fiber, with a low zero-dispersion wavelength, was prepared by an innovative preparation process. The composition optimized fiber has a wide transmission range of up to 11.5 µm, a lowest fundamental mode zero-dispersion wavelength of 4.03 µm, and a minimum optical loss of 1.12 dB/m at 6.4 µm, which provides a possibility to replace As2S3 and As2Se3 in a cascade of ZrF4-BaF2-LaF3-AlF3-NaF(ZBLAN)-As2S3-As2Se3 fiber in the practical all-fiberized supercontinuum (SC) source. Meanwhile, the broadest SC spectrum, ∼1.2 to 15.2 µm, was achieved by pumping a 12-cm-long fiber with a femtosecond laser at a deep anomalous-dispersion region. Furthermore, simulations are adopted to interpret the results as well as to demonstrate spectral evolution along the fiber. To the best of our knowledge, this is the broadest SC spectrum reported in any selenium-based chalcogenide fiber.

7.
Environ Pollut ; 250: 537-545, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31026701

RESUMO

This study examined the influences of three subsets of environmental factors (i.e. soil physicochemical properties including pH, organic matters and soil texture, landscape patterns, and parent materials) on the spatial variations and sources of soil trace metal contamination across an urban-rural environmental gradient in Guangzhou City, southern China. We collected 318 surface soil samples from forests, orchards, farmlands, and urban lawns using a random tessellation design for selecting sample sites. The geo-accumulation indices showed that 18%-88% of soil samples were contaminated: moderate to high contamination with Cd and Hg, low to moderate contamination with Cu, Pb, Zn and Ni, and low contamination with As and Cr. However, less than 13% of soil samples were considered to have exceeded the national standards causing environmental and human health concerns. The mean geo-accumulation indices increased in the order of forest, paddy field/orchard, vegetable, road/residential, and park/residential areas for As, Cd, Ni, Pb, Zn, closely following a land disturbance gradient. Spearman Correlation and Cluster Analyses showed that Pb-Cu-Zn had traffic-related origins, Cd-Hg were mainly influenced by fertilization or industrial emissions, and As-Cr-Ni had geogenic origins for agricultural soils. In contrast, the Ni, Hg and Cd contamination sources for urban soils included both anthropogenic and geogenic origins. The Stepwise Regression and Partial Redundancy Analyses showed that three subsets of environmental factors explained 43%-87% of variations of soil contamination for both agricultural and urban soils. We concluded that soil contamination was mainly controlled by soil physiochemical properties followed by landscape patterns. Soil absorption of aerial loads of trace metal pollutants dominated the soil contamination processes. Our findings implied that improving soil physiochemical properties and landscape designs can strengthen environmental buffering and carrying capacity, thus alleviating soil contamination and reducing non-point-source pollution in the study region.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Agricultura , China , Cidades , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Florestas , Humanos , Indústrias , Solo/química , Oligoelementos/análise , Verduras
8.
Opt Express ; 27(3): 2036-2043, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732248

RESUMO

We have prepared a well-structured tellurium chalcogenide (ChG) fiber with a specialized double cladding structure by an improved extrusion method, and experimentally demonstrated an ultra-flat mid-infrared (MIR) supercontinuum (SC) generation in such a fiber. The step-index fiber had an optical loss of <1 dB/m in a range from 7.4 to 9.7 µm with a minimum loss of 0.69 dB/m at 7.87 µm. Simulation showed that an all-normal dispersion profile can be realized in this double cladding tellurium fiber. An ultra-flat MIR SC spectrum (~3.2-12.1µm at -10 dB, ~2-14 µm at -30 dB) was generated from a 22-cm long fiber pumped with a femtosecond laser at 5 µm (~150 fs, 1 kHz). Then the degree of coherence was calculated out based on a simulation, showing that a high coherent MIR SC (from 2.9 to 13.1 µm) can be generated in this double-cladding tellurium fiber.

9.
Langmuir ; 34(50): 15143-15149, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30449104

RESUMO

Zn1Sb7Te12 thin films have been deposited by magnetron co-sputtering of ZnTe and Sb2Te3 targets. The microstructure, phase-change speed, optical cycling stability, and crystallization kinetics have been investigated during thermal annealing and laser irradiation. The thermal-annealed and laser-irradiated films give a clear evidence of the coexistence of trigonal Sb2Te3 and cubic ZnTe phases, which are homogeneously distributed in a single alloy as confirmed by advanced scanning transmission electron microscopy. The formation of both phases increases the initial nucleation sites, leading to the rapid phase-change speed in the Zn1Sb7Te12 film. The film has a minimum crystallization time of ∼3 ns at 70 mW with almost no incubation period for the formation of critical nuclei compared to Ge2Sb2Te5 and other Zn-based films. Moreover, the complete crystallization of Zn1Sb7Te12 thin films is achieved within 10 ns. The ultrafast two-dimensional nucleation and crystal growth speed in Zn1Sb7Te12 obtained from the laser-irradiated system is almost 7 times faster compared to that in Ge2Sb2Te5 film. Controlling the crystallization process through doping ZnTe into Sb2Te3 is thus promising for the development of high-speed optical switching technology.

10.
Onco Targets Ther ; 11: 6723-6730, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349305

RESUMO

Background: Circular RNAs (circRNAs) are a class of noncoding RNAs with closed loop structures. There has been growing evidence showing that circRNAs are involved in the pathogenesis of human diseases including various carcinomas. Our study is aimed to investigate the association between a new circRNA named circ-DLG1 (hsa_circ_0007203) and esophageal squamous cell carcinoma (ESCC) carcinogenesis. Methods: The circ-DLG1 expression levels were detected by real-time quantitative reverse transcription-polymerase chain reaction in cells, tissues, and plasmas. The correlation between circ-DLG1 expression and clinicopathologic features was then analyzed. The effect of circ-DLG1 expression on cell proliferation was evaluated in vitro by CCK8 assay and clone formation experiment. Finally, a network of circ-DLG1 with its targeted miRNA interactions and corresponding mRNAs was constructed. Results: circ-DLG1was found to be significantly upregulated in ESCC cells, tissues, and plasmas compared to normal cases. Furthermore, in vitro assays, TE10 and KYSE180, of the ESCC cell lines demonstrated that knockdown of circ-DLG1 reduced cell proliferation significantly. Prediction and annotation revealed that circ-DLG1 was able to sponge to 20 miRNAs and 60 corresponding target mRNAs. Conclusion: Our study indicated that upregulation of circ-DLG1 promoted esophageal cell proliferation ability and might serve as a novel biomarker for ESCC.

11.
Sci Rep ; 8(1): 1671, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29362429

RESUMO

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.

12.
Sci Rep ; 7(1): 14585, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-29097730

RESUMO

We presented the unusual result of photobleaching (PB) in Ge-deficient Ge16.8Se83.2 thin films with continuous irradiation with 560 nm laser for 12000 s, which is contradicted with the previous reports that the PB only occurs in GexSe100-x films with x > 30. Observation of the dynamics variations of the photo-induced effects indicated that, photodarkening (PD) appears almost instantaneously upon light irradiation, saturates faster in a shorter time scale, and then photobleaching (PB) becomes dominant. Moreover, both PD and PB process accelerates with increasing irradiation power density. Raman spectra provided the evidence on the change of the photostructure of the samples, e.g. the structural transformation from Ge(Se1/2)4 edge-sharing (ES) to corner-sharing (CS) tetrahedral and homopolar Ge-Ge and Se-Se bonds to heteropolar Ge-Se bonds.

13.
Sci Rep ; 7(1): 6497, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747742

RESUMO

In this paper, we report the first measurements of mid-infrared (MIR) femtosecond laser-induced damage in two typical chalcogenide glasses, As2S3 and As2Se3. Damage mechanism is studied via optical microscopy, scanning electron microscopy and elemental analysis. By irradiating at 3, 4 and 5 µm with 150 fs ultrashort pulses, the evolution of crater features is presented with increasing laser fluence. The dependence of laser damage on the bandgap and wavelength is investigated and finally the laser-induced damage thresholds (LIDTs) of As2S3 and As2Se3 at 3 and 4 µm are calculated from the experimental data. The results may be a useful for chalcogenide glasses (ChGs) applied in large laser instruments to prevent optical damage.

14.
Sci Rep ; 7(1): 5783, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28724904

RESUMO

Hypertonic saline (HS) attenuates cerebral edema, improves microcirculation perfusion and alleviates inflammation. However, whether the beneficial effect of HS on neurological function after cardiopulmonary resuscitation (CPR) in rat model of asphyxial cardiac arrest (CA) is mediated via attenuating apoptosis of neurons is not known. We studied the neuroprotective effect of HS in rats after CA and CPR, and explored the likely underlying mechanisms. Animals were randomly assigned to 4 equal groups (n = 15 each) according to the different infusions administered during resuscitation: control (C), normal saline (NS), hypertonic saline (HS), and hydroxyethyl starch (HES) groups. NDS at 12, 24, 48 and 72 h post-ROSC in the HS group were significantly higher than those in the NS and HES groups. Western blot analysis demonstrated a significant increase in Bcl-2 expression in HS, as compared to that in the NS and HES groups. However, Bax and Caspase-3 expressions in HS were significantly lower than that in the NS and HES groups. The apoptosis rate in HS was significantly lower than that in the NS and HES groups, suggesting HS treatment during resuscitation could effectively suppress neuronal cell apoptosis in hippocampal CA1 post-ROSC and improve neuronal function.


Assuntos
Apoptose , Asfixia/complicações , Reanimação Cardiopulmonar/métodos , Parada Cardíaca/terapia , Hipocampo/patologia , Fármacos Neuroprotetores/administração & dosagem , Solução Salina Hipertônica/administração & dosagem , Animais , Modelos Animais de Doenças , Neurônios/patologia , Ratos , Resultado do Tratamento
15.
J Thorac Dis ; 9(5): 1273-1280, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28616278

RESUMO

BACKGROUND: The application of thoracic endovascular aortic repair (TEVAR), a minimally invasive operation, in the aortic arch has been a challenge of cardiovascular surgery in recent years. This study aimed to investigate management of the vertebral artery with coverage of the left subclavian artery (LSA) during TEVAR. METHODS: From January 2007 to September 2014 in the Department of Cardiothoracic Surgery at Wuhan General Hospital of Guangzhou Military Region, 160 patients underwent LSA closure or partial coverage during TEVAR of an aortic lesion near the LSA. The vertebral artery treatment, the reason for the surgical approach selection, and the prognosis were analyzed. RESULTS: In 94 patients with partial LSA coverage during TEVAR, no treatment was provided for the vertebral arteries, revealing blood flow of the left vertebral artery forward into the skull after surgery. For 66 patients with full LSA coverage (closure) during TEVAR, right carotid artery-left common carotid artery bypass surgery was performed before TEVAR in ten patients, without any treatment for the vertebral artery, showing reverse blood flow of the left vertebral artery after surgery. Left common carotid artery-LSA bypass surgery was performed before TEVAR in four patients; right common carotid artery-left common carotid artery-LSA bypass surgery was performed before TEVAR in three cases, and 6 out of these 7 patients underwent proximal LSA ligation, showing no obvious blood flow in the left vertebral artery. The closure of the LSA aortic arch opening using an occluder was performed in one patient, preserving the forward blood flow in the left vertebral artery. Among the 160 patients in this study, postoperative recurrent laryngeal nerve injury occurred in one patient after right common carotid artery-left common carotid artery-LSA bypass surgery, and the remaining 159 patients had no significant severe complications or death within 1 postoperative month. CONCLUSIONS: Appropriate management of the aortic arch branch vessels may expand the application of TEVAR to the aortic arch and reduce complications, especially for high-risk patients who have a difficult time tolerating thoracotomy.

16.
Opt Express ; 24(25): 28400-28408, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27958550

RESUMO

In this study, the supercontinuum (SC) generation in a 1-m-long As2S3 fiber with a 200 µm core diameter was demonstrated experimentally. The high-purity As2S3 fiber we used exhibited very low optical loss with a background loss of approximately 0.1 dB/m at a wavelength of 2-5 µm. SC generation was studied by pumping the fiber at different wavelengths and different peak powers. A strong spectral broadening with a 30 dB spectral flatness spanning from 1.4 to 7.0 µm was obtained when the fiber was pumped with 150 fs short pulses at 5.0 µm. The SC generation in bent fiber was also studied. The result showed that the bending radius of the fiber will significantly affect the SC spectra bandwidth and the output power. The SC spectra in the used fiber could still be maintained when it was bent to a radius of 5 cm.

17.
Opt Express ; 24(20): 23304-23313, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27828394

RESUMO

We report Er-doped Ge-Ga-Se films and waveguides deposited using co-thermal evaporation and patterned with plasma etching. Strong photoluminescence at 1.54 µm with intrinsic lifetime of 1 ms was obtained from deposited films with 1490 nm excitation. Erbium population inversion up to 50% was achieved, with a maximum of ~55% possible at saturation for the first time to the author's knowledge, approaching the theoretical maximum of 65%. Whilst gain was not achieved due to the presence of upconversion pumped photoinduced absorption, this nonetheless represents a further important step towards the realization of future chalcogenide Erbium doped waveguide amplifiers at 1550 nm and in the Mid-infrared.

18.
Opt Lett ; 41(22): 5222-5225, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27842098

RESUMO

We have experimentally demonstrated midinfrared (MIR) supercontinuum (SC) generation in a low-loss Te-based chalcogenide (ChG) step-index fiber. The fiber, fabricated by an isolated extrusion method, has an optical loss of 2-3 dB/m at 6.2-10.3 µm and 3.2 dB/m at 10.6 µm, the lowest value reported for any Te-based ChG step-index fiber. A MIR SC spectrum (∼1.5 to 14 µm) is generated from the 23-cm fiber pumped by a 4.5 µm laser (∼150 fs, 1 kHz). To the best of our knowledge, this is the first SC experimental demonstration in Te-based ChG fiber and the broadest MIR SC generation pumped in the normal dispersion regime in the optical fibers.

19.
Opt Lett ; 41(14): 3201-4, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27420495

RESUMO

We report the fabrication of a novel high nonlinear fiber made of Ge-Sb-Se chalcogenide glasses with high numerical aperture (∼1.0), where the core and the cladding glasses consist of Ge15Sb25Se60 and Ge15Sb20Se65 (mol. %), respectively. The nonlinear refractive index (n2) of the core glass is 19×10-18 m2/W at 1.55 µm, and its laser-induced damage threshold under irradiation of 3.0 µm fs laser is approximately 3674 GW/cm2. By pumping a 20-cm-long fiber with a core diameter of 23 µm using 150 fs pulses at 6.0 µm, supercontinuum spanning from ∼1.8 to ∼14 µm was generated.

20.
Opt Lett ; 41(5): 958-61, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26974090

RESUMO

This Letter reports the production of a supercontinuum extending from ≈2 µm to >10 µm generated using a chalcogenide buried rib waveguide pumped with 330 femtosecond pulses at 4.184 µm. This is, to the best of our knowledge, the broadest mid-infrared supercontinuum generated in any planar waveguide platform. Because the waveguide is birefringent, quasi-single-mode, and uses an optimized dispersion design, the supercontinuum is linearly polarized with an extinction ratio >100. Dual beam spectrophotometry is performed easily using this source.

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