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1.
Prenat Diagn ; 43(13): 1581-1592, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37975672

RESUMO

OBJECTIVES: In general, fetal cfDNA is shorter than maternal cfDNA, and accuracy of noninvasive prenatal testing (NIPT) results can be improved by selecting shorter cfDNA fragments to enrich fetal-derived cfDNA. This study investigated potential improvements in the accuracy of NIPT by performing classification and analysis based on differences in cfDNA size. METHODS: We performed paired-end sequencing to identify size ranges of fetal and maternal cfDNA from 62,374 pregnant women. We then developed a size-selection method to isolate and analyze both fetal and maternal cfDNA, defining fetal-derived cfDNA as less than 150 bp and maternal-derived cfDNA as greater than 180 bp. RESULTS: By implementing size-selection method, the accuracy of NIPT was improved, resulting in an increase in the overall positive predictive value for all aneuploidies from 89.57% to 97.1%. This was achieved by enriching both fetal and maternal-derived cfDNA, which increased fetal DNA fraction while the number of false positives for all aneuploidies was reduced by more than 70%. CONCLUSIONS: We identified the differences in read length between fetal and maternal-derived cfDNA, and selectively enriched both shorter and longer cfDNA fragments for subsequent analysis. Our approach can increase the detection accuracy of NIPT for detecting fetal aneuploidies and reduce the number of false positives caused by maternal chromosomal abnormalities.


Assuntos
Ácidos Nucleicos Livres , Teste Pré-Natal não Invasivo , Gravidez , Feminino , Humanos , Diagnóstico Pré-Natal/métodos , Aneuploidia , Aberrações Cromossômicas
2.
Inorg Chem ; 61(8): 3723-3729, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35179362

RESUMO

Herein, tin(IV) sulfide (SnS2) and multiwalled carbon nanotube (MWCNT) composites are fabricated via a simple solution-mixing method in a hydrothermal reactor. SnS2 is closely coupled to the MWCNT surface, thus forming a coaxial nanostructure. Examination by X-ray photoelectron spectroscopy and scanning transmission electron microscopy indicates that the strong interface between SnS2 and the MWCNTs in the composite material is due to the formation of Sn-O and Sn-S bonds. In addition, an examination of the temperature-dependent thermoelectric (TE) properties demonstrates that the SnS2-MWCNT hybrid composite with 3 wt % MWCNTs exhibits the maximum power factor of ∼91.34 µW/(m·K2) at 500 K, which is ∼50 times larger than that of the pristine SnS2. These results highlight the fabrication and enhanced TE properties of hybrid composites via the coupling of SnS2 and MWCNTs.

3.
J Nanosci Nanotechnol ; 19(3): 1649-1656, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469239

RESUMO

Polyethylene glycol (PEG) based water-soluble polymer composites were fabricated for mineral admixture encapsulants to be used in underground sinkhole restoration. Linear low-density polyethylene (LLDPE) and talc were added to the composites to increase their mechanical strengths and heat resistances. PEG/LLDPE/Talc composites were manufactured via melt mixing using a twin extruder. Blending PEG and LLDPE increased the mechanical properties and heat resistances of the composite, but decreased the water solubility. Talc was added to the composite to increase mechanical properties and heat resistance. The addition of talc increased the water solubilities of PEG-based composites. The highest tensile strength and impact strength were 2.89 MPa and 2.86, respectively, the increase rate being 9.63-fold relative to that of pristine PEG.

4.
Appl Opt ; 55(31): 8738-8742, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27828269

RESUMO

We proposed a method of eliminating the bending-induced retardation of a plastic film by coating it with a polymer layer with an opposite birefringence. We coated a polystyrene (PS) or a poly(methyl methacrylate) (PMMA) layer on a polycarbonate (PC) plastic film. The bare PC film is composed of main-chain-type polymers and showed an increase in retardation with bending. The main-chains of the PC polymer are reoriented along the circular arc direction during bending, resulting in a positive birefringence. In contrast, the 11 wt. % PS-coated and the 19 wt. % PMMA-coated PC films showed minimal change in the retardation regardless of the radius of curvature. The PS and the PMMA polymers are of the side-chain-type, and the side-chains were aligned perpendicular to the circular arc direction during bending, resulting in a negative birefringence. Consequently, the bending-induced retardation of the PC film can be compensated by the PS or the PMMA layer during bending of the film. This method of compensating for the bending-induced retardation of the plastic film can be useful for flexible display applications.

5.
Dalton Trans ; 52(44): 16398-16405, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37870571

RESUMO

Layer-structured Bi2Si2Te6 has garnered significant attention in the field of thermoelectrics due to its exceptional thermoelectric properties and unique structural characteristics. Enhancing the transport properties of composites by manipulating the thermal and electrical properties of materials through the fabrication of porous nanostructured materials has emerged as a promising strategy. This paper presents a study on enhancing the thermoelectric (TE) properties of Bi2Si2Te6 nanosheets (BST NSs) through nanostructuring and the fabrication of porous BST NSs (p-BST). The process involves Li intercalation and exfoliation to obtain BST NSs, followed by the creation of p-BST composites by introducing nanosized pores onto the surface of the NSs using high-power sonification for various durations. The incorporation of the porous structure effectively increases phonon scattering, leading to a decrease in the lattice thermal conductivity (κl) of the composite. The p-BST(2) composite demonstrates significantly low κ and enhanced thermoelectric figure of merit (ZT) values (∼0.63 W m-1 K-1 and ∼0.083) at room temperature. These results highlight the efficacy of porous structure preparation as a promising strategy for enhancing the thermoelectric performance of chalcogenide-based composites, offering potential solutions to environmental degradation and energy shortages.

6.
ChemSusChem ; 16(6): e202201924, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36513946

RESUMO

Herein, surface-functionalized carbon nanotubes (CNTs) were successfully synthesized by dry ball milling that facilitates industrial application. The optimal conditions were determined by analyzing the physicochemical characteristics of CNTs, including the content of the carboxyl group (-COOH) induced on the surface of CNTs by co-existing dry ice based on the ball milling time. Among them, 30 s ball milling (CNTs-30s) showed a high dispersibility in N-methyl-2-pyrrolidone (NMP) while retaining most carboxyl groups and maintaining the intrinsic high conductivity. In the evaluation of rate capability and 5 C/5 C cyclability applied to the Li1+x (Ni1-y-z Coy Mnz )1-x O2 with 60 % Ni (NCM622) cathode, CNTs-30s showed excellent performance based on a well-formed conductive network. Regarding improved dispersion properties and electrochemical performance, the optimal surface functionalization conditions, dispersibility, and electrode properties according to the processing time were analyzed; based on these, the correlation with electrochemical performance was confirmed.

7.
Cancers (Basel) ; 15(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37760525

RESUMO

Early detection of lung cancer is crucial for patient survival and treatment. Recent advancements in next-generation sequencing (NGS) analysis enable cell-free DNA (cfDNA) liquid biopsy to detect changes, like chromosomal rearrangements, somatic mutations, and copy number variations (CNVs), in cancer. Machine learning (ML) analysis using cancer markers is a highly promising tool for identifying patterns and anomalies in cancers, making the development of ML-based analysis methods essential. We collected blood samples from 92 lung cancer patients and 80 healthy individuals to analyze the distinction between them. The detection of lung cancer markers Cyfra21 and carcinoembryonic antigen (CEA) in blood revealed significant differences between patients and controls. We performed machine learning analysis to obtain AUC values via Adaptive Boosting (AdaBoost), Multi-Layer Perceptron (MLP), and Logistic Regression (LR) using cancer markers, cfDNA concentrations, and CNV screening. Furthermore, combining the analysis of all multi-omics data for ML showed higher AUC values compared with analyzing each element separately, suggesting the potential for a highly accurate diagnosis of cancer. Overall, our results from ML analysis using multi-omics data obtained from blood demonstrate a remarkable ability of the model to distinguish between lung cancer and healthy individuals, highlighting the potential for a diagnostic model against lung cancer.

8.
Sci Rep ; 13(1): 13502, 2023 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598236

RESUMO

Methylation patterns in cell-free DNA (cfDNA) have emerged as a promising genomic feature for detecting the presence of cancer and determining its origin. The purpose of this study was to evaluate the diagnostic performance of methylation-sensitive restriction enzyme digestion followed by sequencing (MRE-Seq) using cfDNA, and to investigate the cancer signal origin (CSO) of the cancer using a deep neural network (DNN) analyses for liquid biopsy of colorectal and lung cancer. We developed a selective MRE-Seq method with DNN learning-based prediction model using demethylated-sequence-depth patterns from 63,266 CpG sites using SacII enzyme digestion. A total of 191 patients with stage I-IV cancers (95 lung cancers and 96 colorectal cancers) and 126 noncancer participants were enrolled in this study. Our study showed an area under the receiver operating characteristic curve (AUC) of 0.978 with a sensitivity of 78.1% for colorectal cancer, and an AUC of 0.956 with a sensitivity of 66.3% for lung cancer, both at a specificity of 99.2%. For colorectal cancer, sensitivities for stages I-IV ranged from 76.2 to 83.3% while for lung cancer, sensitivities for stages I-IV ranged from 44.4 to 78.9%, both again at a specificity of 99.2%. The CSO model's true-positive rates were 94.4% and 89.9% for colorectal and lung cancers, respectively. The MRE-Seq was found to be a useful method for detecting global hypomethylation patterns in liquid biopsy samples and accurately diagnosing colorectal and lung cancers, as well as determining CSO of the cancer using DNN analysis.Trial registration: This trial was registered at ClinicalTrials.gov (registration number: NCT04253509) for lung cancer on 5 February 2020, https://clinicaltrials.gov/ct2/show/NCT04253509 . Colorectal cancer samples were retrospectively registered at CRIS (Clinical Research Information Service, registration number: KCT0008037) on 23 December 2022, https://cris.nih.go.kr , https://who.init/ictrp . Healthy control samples were retrospectively registered.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Colorretais , Neoplasias Pulmonares , Humanos , Metilação , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Biópsia Líquida , Fármacos Gastrointestinais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética
9.
Dalton Trans ; 51(26): 10169-10178, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35735163

RESUMO

Copper antimony selenide (Cu3SbSe4), a ternary Cu-based material, is a promising p-type thermoelectric material. In this study, the morphology of Cu3SbSe4 particles was controlled using the shape of Se during the synthesis process. To this end, Se particles with a size of 20 µm were exfoliated to form nanosheets through an ultrasonication process without the oxidation of Se. The variation in the morphology of Cu3SbSe4 nanoparticles and nanosheets affected their grain size, thus affecting their electrical conductivity and lattice thermal conductivity owing to the phonon and electron scattering at the interface of the grains. By combining the effects of the morphological variation with the electrical and lattice thermal conductivity, the Cu3SbSe4 synthesized using Se nanosheets exhibited improved thermoelectric performance. The synthesized Cu3SbSe4 nanosheets achieved a maximum thermoelectric figure of merit value of 0.40, which was 1.41 times higher than that of Cu3SbSe4 nanoparticles.

10.
Sci Rep ; 11(1): 16683, 2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404869

RESUMO

Thermoelectric (TE) composites, with photocured resin as the matrix and Ag2Se (AS) as the filler, are synthesized by a digital-light-processing (DLP) based 3D printer. The mixture of diurethane dimethacrylate (DUDMA) and isobornyl acrylate (IBOA) is used as a UV-curable resin because of their low viscosity and high miscibility. Scanning electron microscopy (FE-SEM) images confirm that the filler retains its shape and remains after the UV-curing process. After completing curing, the mechanical and thermoelectric properties of the composite with different AS contents were measured. The addition of the AS filler increases the thermoelectric properties of the cured resin. When the AS contents increase by 30 wt.%, the maximum power factor was obtained (~ 51.5 µW/m·K2 at room temperature). Additionally, due to the phonon scattering effect between the interfaces, the thermal conductivity of composite is lower than that of pristine photoresin. The maximum thermoelectric figure of merit (ZT) is ~ 0.12, which is achieved with 30 wt.% of AS at 300 K with the enhanced power factor and reduced thermal conductivity. This study presents a novel manufacturing method for a thermoelectric composite using 3D printing.

11.
Polymers (Basel) ; 13(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33435612

RESUMO

We present a simple thermoelectric device that consists of a conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)-based inorganic/organic thermoelectric film with high thermoelectric performance. The PEDOT:PSS-coated Se NWs were first chemically synthesized in situ, and then mixed with an Ag precursor solution to produce the PEDOT:PSS-coated Ag2Se NWs. The PEDOT:PSS matrix was then treated with dimethyl sulfoxide (DMSO) prior to the production of flexible PEDOT:PSS-coated Ag2Se NW/PEDOT:PSS composite films with various weight fractions of Ag2Se via a simple drop-casting method. The thermoelectric properties (Seebeck coefficient, electrical conductivity, and power factor) of the composite films were then analyzed. The composite film with 50 wt.% NWs exhibited the highest power factor of 327.15 µW/m·K2 at room temperature. The excellent flexibility of this composite film was verified by bending tests, in which the thermoelectric properties were reduced by only ~5.9% after 1000 bending cycles. Finally, a simple thermoelectric device consisting of five strips of the proposed composite film was constructed and was shown to generate a voltage of 7.6 mV when the temperature difference was 20 K. Thus, the present study demonstrates that that the combination of a chalcogenide and a conductive composite film can produce a high-performance flexible thermoelectric composite film.

12.
Polymers (Basel) ; 13(9)2021 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-34065076

RESUMO

Herein, Sb2Se3 and ß-Cu2Se nanowires are synthesized via hydrothermal reaction and water evaporation-induced self-assembly methods, respectively. The successful syntheses and morphologies of the Sb2Se3 and ß-Cu2Se nanowires are confirmed via X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), and field emission transmission electron microscopy (FE-TEM). Sb2Se3 materials have low electrical conductivity which limits application to the thermoelectric generator. To improve the electrical conductivity of the Sb2Se3 and ß-Cu2Se nanowires, polyaniline (PANI) is coated onto the surface and confirmed via Fourier-transform infrared spectroscopy (FT-IR), FE-TEM, and XPS analysis. After coating PANI, the electrical conductivities of Sb2Se3/ß-Cu2Se/PANI composites were increased. The thermoelectric performance of the flexible Sb2Se3/ß-Cu2Se/PANI films is then measured, and the 70%-Sb2Se3/30%-ß-Cu2Se/PANI film is shown to provide the highest power factor of 181.61 µW/m·K2 at 473 K. In addition, a thermoelectric generator consisting of five legs of the 70%-Sb2Se3/30%-ß-Cu2Se/PANI film is constructed and shown to provide an open-circuit voltage of 7.9 mV and an output power of 80.1 nW at ΔT = 30 K. This study demonstrates that the combination of inorganic thermoelectric materials and flexible polymers can generate power in wearable or portable devices.

13.
Dalton Trans ; 50(36): 12424-12429, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34490867

RESUMO

In this study, we synthesized a flexible thermoelectric composite film consisting of poly(3,4-ethylenedioxythiopene)-poly(4-styrenesulfonate)-coated selenium nanowires (PEDOT:PSS-coated Se NWs) and multi-walled carbon nanotubes (MWCNTs) via simple solution mixing. PEDOT:PSS-coated Se NWs were synthesized by coating PEDOT:PSS-on the surface of Se during the process of synthesizing Se NWs. Then, flexible PEDOT:PSS-coated Se/MWCNT composite films were synthesized by filtration. To verify the thermoelectric (TE) potential, the TE properties of the composite film with various MWCNT contents were investigated to determine the optimal conditions for improved TE performance. The maximum power factor of the composite film was ∼73.94 µW (m K2)-1, which is much higher than that of Se and PEDOT:PSS. This study suggests an approach to fabricate flexible inorganic/organic hybrid films with high TE performance.

14.
RSC Adv ; 10(19): 11381, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35503550

RESUMO

[This corrects the article DOI: 10.1039/C7RA13572F.].

15.
Polymers (Basel) ; 12(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302518

RESUMO

Flexible Ag2Se NW/PEDOT:PSS thermoelectric composite films with different Ag2Se contents (10, 20, 30, 50, 70, and 80 wt.%) are fabricated. The Ag2Se nanowires are first fabricated with solution mixing. After that, Ag2Se NW/PEDOT:PSS composite film was fabricated using a simple drop-casting method. To evaluate the potential applications of the Ag2Se NW/PEDOT:PSS composite, their thermoelectric properties are analyzed according to their Ag2Se contents, and strategies for maximizing the thermoelectric power factor are discussed. The maximum room-temperature power factor of composite film (178.59 µW/m·K2) is obtained with 80 wt.% Ag2Se nanowires. In addition, the composite film shows outstanding durability after 1000 repeat bending cycles. This work provides an important strategy for the fabrication of high-performance flexible thermoelectric composite films, which can be extended to other inorganic/organic composites and will certainly promote their development and thermoelectric applications.

16.
Polymers (Basel) ; 12(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244794

RESUMO

We present hybrid organic inorganic materials, namely, SrTiO3/polyaniline (PANI) composites, with high thermoelectric performance; samples with various SrTiO3 contents (10, 20, 30, and 50 wt.%) were prepared. The PANI component was obtained through the polymerization of aniline monomers, followed by camphosulfonic acid-doping to enhance its electrical conductivity. SrTiO3, with a high Seebeck coefficient, was used as the N-type inorganic componenet; it was synthesized via a one-pot solvothermal methods and, then, dispersed into the conductive PANI matrix. The SrTiO3 content influenced the Seebeck coefficient and electrical conductivity of the resulting composites. The variations in the thermoelectric properties of the SrTiO3/PANI composites consequently changed their power factor; at room temperature, the highest value was ~49.6 µW·m/K2, which is 17 times larger than that of pure PANI.

17.
J Nanosci Nanotechnol ; 20(1): 603-607, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383219

RESUMO

The effects of thiodiphenol based epoxy resin on the thermal property of the composites containing aluminum oxide were investigated. The thermal conductivities and thermal diffusivities of the composites were dependent on the polymer resin. At the same content of Al2O3, the thermal conductivity and thermal diffusivity of composites made by synthesized polymer resin exhibited higher than that of composite made by bisphenol-A resin. The obtained maximum thermal conductivity of the composite was 0.25 W/mK, which was 0.4 times as large as that of the conventional bisphenol-A epoxy resin which has an amorphous structure. It is supposed that the reason for the high heat conductivity obtained in thiodiphenol based epoxy resin is certain high packing structure.

18.
Cancers (Basel) ; 12(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066190

RESUMO

VEGF(R)-targeted therapies are associated with an increased risk of thromboembolism and bleeding, which might be pronounced in patients with increased cardiovascular risk. Nevertheless, sorafenib represents an important treatment option in patients with hepatocellular carcinoma (HCC). We retrospectively investigated the risk of arterial/venous thromboembolic and bleeding events in 252 patients treated with sorafenib for HCC between 05/2006 and 03/2020 at the Medical University of Vienna. Cardiovascular risk was assessed using Framingham score. Eight patients (3.2%) experienced 11 arterial/venous thromboembolic events. Only two patients (0.8%) developed arterial thromboembolism even though cardiovascular risk was low, intermediate, and high in 15 (8.7%), 104 (60%), and 54 (31.2%) of 173 assessable patients. Median overall survival (OS) was shorter in the high risk vs. low/intermediate risk group 7.4 (95% CI: 3.4-11.3) vs. 10.0 (95% CI: 6.8-13.2 months) and independently associated with OS in multivariable analysis HR: 1.53 (95% CI: 1.07-2.19; p = 0.019). Forty-eight (19%) patients experienced a bleeding, most commonly gastrointestinal bleeding (14%) followed by epistaxis (4.7%). Advanced liver dysfunction was not associated with an increased incidence of bleeding/venous thromboembolism. Sorafenib represents a safe treatment option even in patients with increased cardiovascular risk. Bleeding complications were comparable with previous reports, even though patients with more advanced liver disease were included.

19.
Nanoscale ; 11(34): 16114-16121, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31432843

RESUMO

Te-Substituted SnSe nanosheets (Te-s-SnSe NSs) with a lateral size of ∼500 nm are fabricated and their surfaces are then coated with a poly(3,4-ethylenedioxythiophene) PEDOT nanolayer. The 3,4-ethylenedioxythiophene loading is optimized for achieving outstanding thermoelectric performance and the resulting PEDOT-coated nanosheets (PEDOT-Te-s-SnSe NSs) are alternately stacked with PEDOT:poly(styrenesulfonate) (PSS) using a solution-processable method to obtain multilayer inorganic/organic composite films. The as-fabricated multilayer films exhibit outstanding electrical conductivity and Seebeck coefficient. This is due to the enhanced interchain interaction and charge-carrier hopping of the stretched PEDOT chains as well as the presumable energy-filtering effect at the interfacial potential barriers between inorganic and organic layers. The multilayer film consisting of three-repeated stacking allows a maximum thermoelectric power factor of 222 µW m-1 K-2, which is 5.5 times larger than that achieved with pristine PEDOT:PSS. This strategy of combining inorganic and organic materials into multilayer films is promising for the achievement of high-performance thin-film thermoelectrics.

20.
Nanoscale ; 11(17): 8502-8509, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30990488

RESUMO

The chemical exfoliation of SnSe0.97Te0.03 nanosheets is performed via a solid-state reaction, ball-milling, lithium intercalation, and a hydrothermal exfoliation reaction from atomic materials, and the potential of flexible thermoelectric composite films for practical applications is demonstrated. The exfoliated SnSe0.97Te0.03 nanosheets are very thin, ∼300 nm in lateral size, and coated with nanosize poly(3,4-ethylenedioxythiophene) (PEDOT), which exhibits great affinity to the PEDOT:PSS matrix compared with the SnSe0.97Te0.03 nanosheets without PEDOT coating. The enhanced thermoelectric performance can be explained by the fact that the PEDOT nano-coating on the surface of the SnSe0.97Te0.03 nanosheets contributes to the excellent distribution of the SnSe0.97Te0.03 nanosheets in the composite system. The thermoelectric performance is also enhanced with the increase of the PEDOT-coated SnSe0.97Te0.03 nanosheets, and a PEDOT-coated SnSe0.97Te0.03 nanosheet/PEDOT:PSS composite with 20 wt% of PEDOT-coated SnSe0.97Te0.03 nanosheets exhibits a maximum figure of merit (ZT) of 0.18, which is ∼61% higher than that of the composite sample without the PEDOT coating process. The results provide a promising strategy for inorganic/organic composite-based efficient thermoelectrics.

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