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1.
Nature ; 596(7873): 525-530, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34433941

RESUMO

Lithium-ion batteries (LIBs) are widely used in applications ranging from electric vehicles to wearable devices. Before the invention of secondary LIBs, the primary lithium-thionyl chloride (Li-SOCl2) battery was developed in the 1970s using SOCl2 as the catholyte, lithium metal as the anode and amorphous carbon as the cathode1-7. This battery discharges by lithium oxidation and catholyte reduction to sulfur, sulfur dioxide and lithium chloride, is well known for its high energy density and is widely used in real-world applications; however, it has not been made rechargeable since its invention8-13. Here we show that with a highly microporous carbon positive electrode, a starting electrolyte composed of aluminium chloride in SOCl2 with fluoride-based additives, and either sodium or lithium as the negative electrode, we can produce a rechargeable Na/Cl2 or Li/Cl2 battery operating via redox between mainly Cl2/Cl- in the micropores of carbon and Na/Na+ or Li/Li+ redox on the sodium or lithium metal. The reversible Cl2/NaCl or Cl2/LiCl redox in the microporous carbon affords rechargeability at the positive electrode side and the thin alkali-fluoride-doped alkali-chloride solid electrolyte interface stabilizes the negative electrode, both are critical to secondary alkali-metal/Cl2 batteries.

2.
Proc Natl Acad Sci U S A ; 120(39): e2310903120, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37729201

RESUMO

Advancing new ideas of rechargeable batteries represents an important path to meeting the ever-increasing energy storage needs. Recently, we showed rechargeable sodium/chlorine (Na/Cl2) (or lithium/chlorine Li/Cl2) batteries that used a Na (or Li) metal negative electrode, a microporous amorphous carbon nanosphere (aCNS) positive electrode, and an electrolyte containing dissolved aluminum chloride and fluoride additives in thionyl chloride [G. Zhu et al., Nature 596, 525-530 (2021) and G. Zhu et al., J. Am. Chem. Soc. 144, 22505-22513 (2022)]. The main battery redox reaction involved conversion between NaCl and Cl2 trapped in the carbon positive electrode, delivering a cyclable capacity of up to 1,200 mAh g-1 (based on positive electrode mass) at a ~3.5 V discharge voltage [G. Zhu et al., Nature 596, 525-530 (2021) and G. Zhu et al., J. Am. Chem. Soc. 144, 22505-22513 (2022)]. Here, we identified by X-ray photoelectron spectroscopy (XPS) that upon charging a Na/Cl2 battery, chlorination of carbon in the positive electrode occurred to form carbon-chlorine (C-Cl) accompanied by molecular Cl2 infiltrating the porous aCNS, consistent with Cl2 probed by mass spectrometry. Synchrotron X-ray diffraction observed the development of graphitic ordering in the initially amorphous aCNS under battery charging when the carbon matrix was oxidized/chlorinated and infiltrated with Cl2. The C-Cl, Cl2 species and graphitic ordering were reversible upon discharge, accompanied by NaCl formation. The results revealed redox conversion between NaCl and Cl2, reversible graphitic ordering/amorphourization of carbon through battery charge/discharge, and probed trapped Cl2 in porous carbon by XPS.

3.
Sensors (Basel) ; 24(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474930

RESUMO

The registration of bridge point cloud data (PCD) is an important preprocessing step for tasks such as bridge modeling, deformation detection, and bridge health monitoring. However, most existing research on bridge PCD registration only focused on pairwise registration, and payed insufficient attention to multi-view registration. In addition, to recover the overlaps of unordered multiple scans and obtain the merging order, extensive pairwise matching and the creation of a fully connected graph of all scans are often required, resulting in low efficiency. To address these issues, this paper proposes a marker-free template-guided method to align multiple unordered bridge PCD to a global coordinate system. Firstly, by aligning each scan to a given registration template, the overlaps between all the scans are recovered. Secondly, a fully connected graph is created based on the overlaps and scanning locations, and then a graph-partition algorithm is utilized to construct the scan-blocks. Then, the coarse-to-fine registration is performed within each scan-block, and the transformation matrix of coarse registration is obtained using an intelligent optimization algorithm. Finally, global block-to-block registration is performed to align all scans to a unified coordinate reference system. We tested our framework on different bridge point cloud datasets, including a suspension bridge and a continuous rigid frame bridge, to evaluate its accuracy. Experimental results demonstrate that our method has high accuracy.

4.
Proc Natl Acad Sci U S A ; 117(45): 27847-27853, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33106405

RESUMO

Potassium secondary batteries are contenders of next-generation energy storage devices owing to the much higher abundance of potassium than lithium. However, safety issues and poor cycle life of K metal battery have been key bottlenecks. Here we report an ionic liquid electrolyte comprising 1-ethyl-3-methylimidazolium chloride/AlCl3/KCl/potassium bis(fluorosulfonyl) imide for safe and high-performance batteries. The electrolyte is nonflammable and exhibits a high ionic conductivity of 13.1 mS cm-1 at room temperature. A 3.6-V battery with K anode and Prussian blue/reduced graphene oxide cathode delivers a high energy and power density of 381 and 1,350 W kg-1, respectively. The battery shows an excellent cycling stability over 820 cycles, retaining ∼89% of the original capacity with high Coulombic efficiencies of ∼99.9%. High cyclability is also achieved at elevated temperatures up to 60 °C. Uniquely, robust K, Al, F, and Cl-containing passivating interphases are afforded with this electrolyte, which is key to superior battery cycling performances.

5.
J Am Chem Soc ; 144(49): 22505-22513, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36450002

RESUMO

Developing new types of high-capacity and high-energy density rechargeable batteries is important to future generations of consumer electronics, electric vehicles, and mass energy storage applications. Recently, we reported ∼3.5 V sodium/chlorine (Na/Cl2) and lithium/chlorine (Li/Cl2) batteries with up to 1200 mAh g-1 reversible capacity, using either a Na or a Li metal as the negative electrode, an amorphous carbon nanosphere (aCNS) as the positive electrode, and aluminum chloride (AlCl3) dissolved in thionyl chloride (SOCl2) with fluoride-based additives as the electrolyte [Zhu et al., Nature, 2021, 596 (7873), 525-530]. The high surface area and large pore volume of aCNS in the positive electrode facilitated NaCl or LiCl deposition and trapping of Cl2 for reversible NaCl/Cl2 or LiCl/Cl2 redox reactions and battery discharge/charge cycling. Here, we report an initially low surface area/porosity graphite (DGr) material as the positive electrode in a Li/Cl2 battery, attaining high battery performance after activation in carbon dioxide (CO2) at 1000 °C (DGr_ac) with the first discharge capacity ∼1910 mAh g-1 and a cycling capacity up to 1200 mAh g-1. Ex situ Raman spectroscopy and X-ray diffraction (XRD) revealed the evolution of graphite over battery cycling, including intercalation/deintercalation and exfoliation that generated sufficient pores for hosting LiCl/Cl2 redox. This work opens up widely available, low-cost graphitic materials for high-capacity alkali metal/Cl2 batteries. Lastly, we employed mass spectrometry to probe the Cl2 trapped in the graphitic positive electrode, shedding light into the Li/Cl2 battery operation.

6.
Cryobiology ; 98: 80-86, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33386123

RESUMO

Coral reefs worldwide are receding because of detrimental human activities, and cryopreservation of coral larvae would ensure that their genetic biodiversity is not irremediably lost. In recent years, the vitrification and laser warming of coral propagules has demonstrated promising results. During cryopreservation, cellular membranes undergo substantial reconfigurations that may affect survival. Fat enrichment may alter the physical proprieties of cell membranes and improve resistance to low temperatures. Therefore, the aim of this study was to determine whether supplementation of exogenous lipids using liposomes would improve cryosurvival and further development of the vitrified and laser-warmed coral larvae of Seriatopora caliendrum and Pocillopora verrucosa. A vitrification solution (VS) composed of 2 M ethylene glycol (EG), 1 M propylene glycol (PG), 40% (w/v) Ficoll, and 10% gold nanoparticles (at a final concentration of 1.2 × 1018 particles/m3 and an optimised emission wavelength of 535 nm) was chosen. Coral larvae were subjected to vitrification with VS incorporating one of four lipid classes: phosphatidylcholine (PC), phosphatidylethanolamine (PE), erucic acid (EA), and linoleic acid (LA). Warming was achieved using a single laser pulse (300 V, 10 ms pulse width, 2 mm laser beam diameter). A significantly higher vitality rate was observed in S. caliendrum larvae subjected to vitrification and laser warming with EA-incorporated VS, and P. verrucosa larvae vitrified and laser warmed using PE-incorporated VS achieved a significantly higher settlement rate. Our study demonstrated that supplementation of exogenous lipids with liposomes enhances coral larvae cryotolerance and improves cryopreservation outcomes. Lipid enrichment may play a key role in cryobanking coral propagules, and in propagule development after thawing.


Assuntos
Antozoários , Nanopartículas Metálicas , Animais , Criopreservação/métodos , Suplementos Nutricionais , Ouro , Larva , Lasers , Lipídeos , Lipossomos , Vitrificação
7.
Molecules ; 26(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34641425

RESUMO

Edible oils are valuable sources of nutrients, and their classification is necessary to ensure high quality, which is essential to food safety. This study reports the establishment of a rapid and straightforward SALDI-TOF MS platform used to detect triacylglycerol (TAG) in various edible oils. Silver nanoplates (AgNPts) were used to optimize the SALDI samples for high sensitivity and reproducibility of TAG signals. TAG fingerprints were combined with multivariate statistics to identify the critical features of edible oil discrimination. Eleven various edible oils were discriminated using principal component analysis (PCA). The results suggested the creation of a robust platform that can examine food adulteration and food fraud, potentially ensuring high-quality foods and agricultural products.


Assuntos
Grão Comestível/química , Nanopartículas Metálicas/química , Óleos de Plantas/análise , Óleos de Plantas/classificação , Prata/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Triglicerídeos/análise , Análise de Alimentos/métodos , Análise de Componente Principal
8.
Cancer Invest ; 38(5): 277-288, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32267175

RESUMO

The aim of this work was to determine whether tumor resection could improve the prognosis of M1a nonsmall-cell lung cancer (NSCLC) patients. We obtained patient data from the Surveillance, Epidemiology, and End Results (SEER) database and used propensity score matching (PSM) to reduce the influence of confounding variables. Univariate and multivariate Cox regression analyses were used to identify independent prognostic factors, and the prediction results were visualized using the nomogram. A total of 772 patients with and without tumor resection were enrolled after PSM, and the nomogram combined with independent prognostic factors including age, sex, histological type, grade, T stage, N stage, chemotherapy, and surgery showed great prediction and discriminatory ability. Tumor resection is possibly a better choice for these patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Análise Multivariada , Estadiamento de Neoplasias/métodos , Nomogramas , Prognóstico , Pontuação de Propensão , Modelos de Riscos Proporcionais , Programa de SEER
9.
Langmuir ; 35(47): 15114-15120, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31675238

RESUMO

Truncated silver nanodecahedrons (TAgNDs) and truncated silver nanoplates (TAgNPs) fabricated via chemical reduction and photochemical methods were added to poly[3,4-ethylenedioxythiophene]:poly[styrenesulfonate] (PEDOT:PSS) as dopants to promote the luminous efficiency of blue-emitting polymer light-emitting diodes (PLEDs). The differences in shape between TAgNDs and TAgNPs result in better dispersion of TAgNDs in PEDOT:PSS. Therefore, at an optimal doping concentration (the distributed density in the light-emitting region is 6.88 µg cm-2 for TAgNDs and 5.16 µg cm-2 for TAgNPs), the average current efficacy and maximum electroluminescence intensity enhancement factor for TAgND-doped PLEDs were 4.18 cd A-1 and 420%, respectively, which are much higher than those for TAgNP-doped PLEDs (1.83 cd A-1 and 200%) at a luminescence wavelength of 440 nm.

10.
Opt Lett ; 42(17): 3411-3414, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957050

RESUMO

The coupling of surface plasmons and excitons in the emissive layer (EML) can improve the performance of polymer light-emitting diodes (PLEDs). Silver nanoparticles (Ag-NPs) with a decahedron structure are prepared by the chemical reduction and photochemical methods and doped directly into the EML after the phase-transfer process. The surface plasmon resonance effect of Ag-NPs, which makes full use of quenched excitons and increases the efficiency of excitons in the EML in a PLED, enhances the current efficacy by a factor of 75 relative to that of the undoped reference device (from 0.22 to 16.64 cd/A). These results demonstrate that Ag-NPs can assist in simple and low-cost fabrication of high-performance polymer optoelectronic devices.

11.
Chemphyschem ; 17(16): 2551-7, 2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27129025

RESUMO

A photoassisted citrate reduction reaction under blue LEDs is an easy and highly reproducible method to synthesize high-yield decahedral silver nanoparticles (AgNPs) in the absence of seeds in the initial photochemical reaction. In this study, icosahedral AgNPs with sizes of 80 to 150 nm could be synthesized by using the photoassisted tartrate reduction method under UV light with a wavelength of λ=(310±12) nm. The product yield of icosahedral AgNPs is higher than 90 %. SAED (selected-area electron diffraction) patterns and XRD (X-ray diffraction) spectra show that these AgNPs have multiply twinned structures. High-resolution TEM and dark-field TEM show that the facet of the triangular planes of these icosahedral AgNPs is {111}. This is the first report of icosahedral AgNPs synthesized by using a seed-free photochemical method. SERS (surface-enhanced Raman scattering) of Crystal Violet (CV) measurements show that the as-prepared icosahedral AgNP colloids have excellent SERS enhancement factors, which are approximately four and six times the enhancement factors of decahedral AgNP colloids and thermal-citrate-reduction AgNP colloids, respectively.

12.
Chemphyschem ; 16(15): 3254-63, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26269109

RESUMO

Silver nanoparticles can be prepared by using a seed-free photo-assisted citrate reduction method under the irradiation of a sodium lamp. Under the same irradiation intensity, bath temperatures are crucial in influencing the reaction rate, morphologies of final products, and shape evolution of the silver nanostructures. For example, when the bath temperature is 80 °C, the product yields of silver nanoplates, nanorods, and nanodecahedra are 38±6 %, 35±10 %, and 12±8 %, respectively. However, when the bath temperature is 30 °C, the product yields of silver nanoplates, nanorods, and nanodecahedra are 6±3 %, 0 %, and 83±16 %, respectively. Time-dependent UV/Vis spectra and TEM images show that silver nanoplates were formed at the earlier reaction stage and greatly decreased in amount at the later stage when the bath temperatures are less than or equal to 40 °C. This indicates that the silver nanoplates, which can be regarded as intermediates, are kinetically favored products. They are not thermodynamically favored products at these relatively low bath temperatures. The SERS spectra of crystal violet (CV) show that all the silver colloids synthesized at various temperatures exhibit good enhancement factors and that the colloids prepared at lower bath temperatures have a higher enhancement factor.


Assuntos
Nanopartículas , Fotoquímica , Prata/química , Sódio/química , Temperatura
13.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(4): 533-6, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26480653

RESUMO

OBJECTIVE: To investigate the regulatory effect of B cell activating transcription factor (BATF) on acute airway inflammation and its association with retinoic acid orphan nuclear receptors gammat (RORyt) in asthmatic mice. METHODS: 24 female BALB/c mice were randomly and equally divided into three groups (n 8): normal saline (NS) treated, asthma (AS) control and dexamethasone (DEX) treated. AS mice were sensitized and challenged with OVA to establish murine asthma model. Histological changes in lung tissues of the mice were observed by HE staining. Numbers of white blood cell (WBC), polymorphonuclear leukocyte (PMN) and eosinophils (EOS) in the bronchoalveolar lavage fluid (BALF) of the mice were counted. The concentration of interleukin-17 (IL-17) in BALF was measured by ELISA. Quantitative real-time PCR (RT-PCR) was performed to assess the mRNA expressions of BATF, IL-17 and RORγt in the lung tissues. RESULTS: The HE staining showed a higher level of inflammatory cell infiltration around the bronchi of AS mice compared with those treated with NS, predominantly in the forms of EOS, PMN and lymphocytes. The AS and DEX treated mice had higher levels of EOS, PMN, WBC and mRNA expressions of BATF, IL-17 and RORγt in BALF than those treated with NS (P < 0.05). DEX reduced the levels of EOS, PMN, WBC and IL-17 in BALF significantly (P < 0.05). The mRNA expression of BATF in lung tissues of mice was positively correlated with the expression of IL-17, RORγt and the counts of WBC,EOS and PMN in BALF (P < 0.05). CONCLUSION: Asthmatic mice have increased expressions of BATF, IL-17 and RORγt in bronchial and lung tissues. BATF can, through regulating the secretion of Th17 cells, readjust the airway inflammatory. The regulatory function may take effect through synergy with RORγt .


Assuntos
Fatores Ativadores da Transcrição/metabolismo , Asma/patologia , Inflamação/patologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Asma/metabolismo , Brônquios , Líquido da Lavagem Broncoalveolar , Dexametasona , Eosinófilos/citologia , Feminino , Interleucina-17/metabolismo , Contagem de Leucócitos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Células Th17/citologia
14.
Adv Mater ; 36(7): e2307192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37804146

RESUMO

Low temperature rechargeable batteries are important to life in cold climates, polar/deep-sea expeditions, and space explorations. Here, this work reports 3.5-4 V rechargeable lithium/chlorine (Li/Cl2 ) batteries operating down to -80 °C, employing Li metal negative electrode, a novel carbon dioxide (CO2 ) activated porous carbon (KJCO2 ) as the positive electrode, and a high ionic conductivity (≈5-20 mS cm-1 from -80 °C to room-temperature) electrolyte comprised of aluminum chloride (AlCl3 ), lithium chloride (LiCl), and lithium bis(fluorosulfonyl)imide (LiFSI) in low-melting-point (-104.5 °C) thionyl chloride (SOCl2 ). Between room-temperature and -80 °C, the Li/Cl2 battery delivers up to ≈29 100-4500 mAh g-1 first discharge capacity (based on carbon mass) and a 1200-5000 mAh g-1 reversible capacity over up to 130 charge-discharge cycles. Mass spectrometry and X-ray photoelectron spectroscopy probe Cl2 trapped in the porous carbon upon LiCl electro-oxidation during charging. At -80 °C, Cl2 /SCl2 /S2 Cl2 generated by electro-oxidation in the charging step are trapped in porous KJCO2 carbon, allowing for reversible reduction to afford a high discharge voltage plateau near ≈4 V with up to ≈1000 mAh g-1 capacity for SCl2 /S2 Cl2 reduction and up to ≈4000 mAh g-1 capacity at ≈3.1 V plateau for Cl2 reduction.

15.
J Photochem Photobiol B ; 251: 112844, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38224669

RESUMO

Gold nanoparticles (GNPs) are usually formed via a wet chemical method using gold (III) chloride trihydrate (GC), which is treated with stable reducing agents such as sodium citrate (SC). This study determines the effect of coloured light on the formation of GNPs by irradiation of SC after the addition of GC (SCGC) and the effect of the SCGC photolytic procedure on the suppression of WiDr colon cancer cells by forming reactive oxygen species. The absorbance of surface plasmon resonance peaks at 523 nm are 0.069 and 0.219 for SCGC when treated with blue light illumination (BLI) and violet light irradiation (VLI), respectively, whereas green and red light treatments have little or no effect. Most GNPs have diameters ranging from 3 to 15 nm, with a mean of 6 nm, when SCGC is exposed to VLI for 1.5 h. Anionic superoxide radicals (O2•-) are formed in a charge-transfer process after SCGC under VLI treatment; however, BLI treatment produces no significant reaction. Moreover, SCGC under VLI treatment proves to be considerably more effective at inhibiting WiDr cells than BLI treatment, as firstly reported in this study. The reduction rates for WiDr cells treated with SCGC under BLI and VLI at an intensity of 2.0 mW/cm2 for 1.5 h (energy dose, 10.8 J/cm2) are 4.1% and 57.7%, respectively. The suppression rates for WiDr cells treated with SCGC are inhibited in an irradiance-dependent manner, the inhibition percentages being 57.7%, 63.3%, and 80.2% achieved at VLI intensities of 2.0, 4.0, and 6.0 mW/cm2 for 1.5 h, respectively. Propidium iodide is a fluorescent dye that detects DNA changes after cell death. The number of propidium iodide-positive nuclei significantly increases in WiDr cells treated with SCGC under VLI, suggesting that SCGC photolysis under VLI is a potential treatment option for the photodynamic therapy process.


Assuntos
Neoplasias do Colo , Compostos de Ouro , Nanopartículas Metálicas , Humanos , Citrato de Sódio , Nanopartículas Metálicas/toxicidade , Ouro/farmacologia , Fotólise , Propídio , Neoplasias do Colo/tratamento farmacológico
16.
Biopreserv Biobank ; 21(4): 427-432, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36036798

RESUMO

Vitrification and laser warming have gained popularity over the traditional convective warming techniques in cryopreservation. Laser warming is rapid with uniform effects, thus preventing ice crystal formation in samples. Contemporary laser warming studies have focused on proof-of-concept experiments. Yet, no protocols or techniques have been developed to address the problem of warming samples from long-term storage. Herein, a new approach to laser warming samples without exposing the samples to ambient temperature is introduced. The new device presented has a mean laser-hitting accuracy of 76% ± 16% and a rewarming rate of 59% ± 25% on samples with <1 µL in volume. Although these rates depend on the choice of vitrification solution and mastery of the technique, the approach described represents a successful first step toward laser warming samples from long-term cryo-storage.


Assuntos
Criopreservação , Vitrificação , Criopreservação/métodos , Lasers
17.
Bioengineering (Basel) ; 10(5)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37237675

RESUMO

Vitrification and ultrarapid laser warming are crucial for the cryopreservation of animal embryos, oocytes, and other cells of medicinal, genetic, and agricultural value. In the present study, we focused on alignment and bonding techniques for a special cryojig that combines a jig tool and jig holder into one piece. This novel cryojig was used to obtain a high laser accuracy of 95% and a successful rewarming rate of 62%. The experimental results indicated that our refined device improved laser accuracy in the warming process after long-term cryo-storage through vitrification. We anticipate that our findings will lead to cryobanking applications that use vitrification and laser nanowarming to preserve cells and tissues from a wide range of species.

18.
Comput Biol Med ; 167: 107596, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37890423

RESUMO

Organ segmentation in abdominal or thoracic computed tomography (CT) images plays a crucial role in medical diagnosis as it enables doctors to locate and evaluate organ abnormalities quickly, thereby guiding surgical planning, and aiding treatment decision-making. This paper proposes a novel and efficient medical image segmentation method called SUnet for multi-organ segmentation in the abdomen and thorax. SUnet is a fully attention-based neural network. Firstly, an efficient spatial reduction attention (ESRA) module is introduced not only to extract image features better, but also to reduce overall model parameters, and to alleviate overfitting. Secondly, SUnet's multiple attention-based feature fusion module enables effective cross-scale feature integration. Additionally, an enhanced attention gate (EAG) module is considered by using grouped convolution and residual connections, providing richer semantic features. We evaluate the performance of the proposed model on synapse multiple organ segmentation dataset and automated cardiac diagnostic challenge dataset. SUnet achieves an average Dice of 84.29% and 92.25% on these two datasets, respectively, outperforming other models of similar complexity and size, and achieving state-of-the-art results.


Assuntos
Coração , Redes Neurais de Computação , Semântica , Tórax , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador
19.
Nanomaterials (Basel) ; 13(16)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37630923

RESUMO

In this study, differently shaped silver nanoparticles used for the synthesis of gold nanoclusters with small capping ligands were demonstrated. Silver nanoparticles provide a reaction platform that plays dual roles in the formation of Au NCs. One is to reduce gold ions and the other is to attract capping ligands to the surface of nanoparticles. The binding of capping ligands to the AgNP surface creates a restricted space on the surface while gold ions are being reduced by the particles. Four different shapes of AgNPs were prepared and used to examine whether or not this approach is dependent on the morphology of AgNPs. Quasi-spherical AgNPs and silver nanoplates showed excellent results when they were used to synthesize Au NCs. Spherical AgNPs and triangular nanoplates exhibited limited synthesis of Au NCs. TEM images demonstrated that Au NCs were transiently assembled on the surface of silver nanoparticles in the method. The formation of Au NCs was observed on the whole surface of the QS-AgNPs if the synthesis of Au NCs was mediated by QS-AgNPs. In contrast, formation of Au NCs was only observed on the edges and corners of AgNPts if the synthesis of Au NCs was mediated by AgNPts. All of the synthesized Au NCs emitted bright red fluorescence under UV-box irradiation. The synthesized Au NCs displayed similar fluorescent properties, including quantum yields and excitation and emission wavelengths.

20.
Micromachines (Basel) ; 13(8)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893173

RESUMO

With the resistive random access memory (ReRAM) devices based on the Al/BaTiO3 (BTO)/ITO structure fabricated at hand, by cross-analyzing the resistive memory characteristics in terms of various barium titanate (BTO) film thicknesses, it is found that the device with 60 nm thick BTO can be switched more than 425 times, while the corresponding SET/RESET voltage, the on-off ratio, and the retention time are -0.69 V/0.475 V, 102, and more than 104 seconds, respectively. Furthermore, the aforementioned ReRAM with a low switching voltage and low power consumption is further integrated with a waveguide resonator in the form of a dual microdisk aligned in a parallel fashion. As the separation gap between the two microdisks is fixed at 15 µm, the ReRAM-mediated dual disk resonator would render a 180° phase reversal between the spectral outputs of the through-port and drop-port. If the gap is shortened to 10 and 5 µm, the expected phase reversal could also be retrieved due to the selective combinations of different memory states associated with each of the two ReRAM microdisks as witnessed by a series of characterization measurements.

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