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1.
Proc Natl Acad Sci U S A ; 119(25): e2122866119, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35696586

RESUMEN

Magneto-ionics, real-time ionic control of magnetism in solid-state materials, promise ultralow-power memory, computing, and ultralow-field sensor technologies. The real-time ion intercalation is also the key state-of-charge feature in rechargeable batteries. Here, we report that the reversible lithiation/delithiation in molecular magneto-ionic material, the cathode in a rechargeable lithium-ion battery, accurately monitors its real-time state of charge through a dynamic tunability of magnetic ordering. The electrochemical and magnetic studies confirm that the structural vacancy and hydrogen-bonding networks enable reversible lithiation and delithiation in the magnetic cathode. Coupling with microwave-excited spin wave at a low frequency (0.35 GHz) and a magnetic field of 100 Oe, we reveal a fast and reliable built-in magneto-ionic sensor monitoring state of charge in rechargeable batteries. The findings shown herein promise an integration of molecular magneto-ionic cathode and rechargeable batteries for real-time monitoring of state of charge.

2.
Neurochem Res ; 49(7): 1735-1750, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38530508

RESUMEN

The consumption of a high-fat diet (HFD) has been implicated in the etiology of obesity and various neuropsychiatric disturbances, including anxiety and depression. Compelling evidence suggests that far-infrared ray (FIR) possesses beneficial effects on emotional disorders. However, the efficacy of FIR therapy in addressing HFD-induced anxiety and the underlying mechanisms remain to be elucidated. Here, we postulate that FIR emitted from a graphene-based therapeutic device may mitigate HFD-induced anxiety behaviors. The graphene-FIR modify the gut microbiota in HFD-mice, particularly by an enriched abundance of beneficial bacteria Clostridiaceae and Erysipelotrichaceae, coupled with a diminution of harmful bacteria Lachnospiraceae, Anaerovoracaceae, Holdemania and Marvinbryantia. Graphene-FIR also improved intestinal barrier function, as evidenced by the augmented expression of the tight junction protein occludin and G protein-coupled receptor 43 (GPR43). In serum level, we observed the decreased free fatty acids (FFA), lipopolysaccharides (LPS), diamine oxidase (DAO) and D-lactate, and increased the glucagon-like peptide-2 (GLP-2) levels in graphene-FIR mice. Simultaneously, inflammatory cytokines IL-6, IL-1ß, and TNF-α manifested a decrease subsequent to graphene-FIR treatment in both peripheral and central system. Notably, graphene-FIR inhibited over expression of astrocytes and microglia. We further noticed that the elevated the BDNF and decreased TLR4 and NF-κB expression in graphene-FIR group. Overall, our study reveals that graphene-FIR rescued HFD-induced anxiety via improving the intestine permeability and the integrity of blood-brain barrier, and reduced inflammatory response by down regulating TLR4/NF-κB inflammatory pathway.


Asunto(s)
Ansiedad , Dieta Alta en Grasa , Microbioma Gastrointestinal , Grafito , Ratones Endogámicos C57BL , Animales , Dieta Alta en Grasa/efectos adversos , Masculino , Grafito/uso terapéutico , Grafito/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Ansiedad/etiología , Ansiedad/metabolismo , Rayos Infrarrojos/uso terapéutico , Obesidad/metabolismo , Ratones , Enfermedades Neuroinflamatorias/metabolismo , Ratones Obesos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de los fármacos
3.
Vascular ; : 17085381241247613, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38631687

RESUMEN

OBJECTIVE: To review our multi-institutional experience with endovascular therapy for right subclavian artery occlusive disease and to evaluate the long-term outcomes. METHODS: We retrospectively evaluated all patients with right subclavian artery stenosis and occlusive disease who underwent endovascular therapy between March 2014 and September 2022 at two institutions. Patient baseline demographics, lesion characteristics, treatment strategies, and in-hospital and follow-up outcomes were prospectively collected and retrospectively analyzed. RESULTS: Between March 2014 and September 2022, 73 patients underwent endovascular treatment at the two institutions. The dominant cause of lesions in this cohort was atherosclerosis. Three different types of lesions were summarized, and the corresponding endovascular strategies were performed. 66 patients (90.4%) underwent successful endovascular treatment, and 62 patients (84.9%) underwent balloon-expandable stent deployment. The mean perioperative in-hospital stay was 4.0 days (range, 3-6 days). Two patients died due to myocardial infarction, and one died of cerebral hemorrhage resulting from a traffic accident within 30 days of the intervention. The median follow-up time was 31.6 months (range, 12-96 months). No complications, including death, stroke, stent fractures, or migration, were noted in any patient during the follow-up period. The overall complication rate was 7/73 (9.6%), and 5/7 (6.9%) of the complications required reintervention. CONCLUSIONS: Endovascular treatment of right subclavian artery lesions is safe, effective, and technically achievable. The reasonable use of balloon-expandable stents can achieve satisfactory outcomes with accurate orientation and promising patency.

4.
Nano Lett ; 23(8): 3107-3115, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37042482

RESUMEN

Two-terminal self-rectifying (SR)-synaptic memristors are preeminent candidates for high-density and efficient neuromorphic computing, especially for future three-dimensional integrated systems, which can self-suppress the sneak path current in crossbar arrays. However, SR-synaptic memristors face the critical challenges of nonlinear weight potentiation and steep depression, hindering their application in conventional artificial neural networks (ANNs). Here, a SR-synaptic memristor (Pt/NiOx/WO3-x:Ti/W) and cross-point array with sneak path current suppression features and ultrahigh-weight potentiation linearity up to 0.9997 are introduced. The image contrast enhancement and background filtering are demonstrated on the basis of the device array. Moreover, an unsupervised self-organizing map (SOM) neural network is first developed for orientation recognition with high recognition accuracy (0.98) and training efficiency and high resilience toward both noises and steep synaptic depression. These results solve the challenges of SR memristors in the conventional ANN, extending the possibilities of large-scale oxide SR-synaptic arrays for high-density, efficient, and accurate neuromorphic computing.

5.
MAGMA ; 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37713007

RESUMEN

BACKGROUND: Quantification of metabolites concentrations in institutional unit (IU) is important for inter-subject and long-term comparisons in the applications of magnetic resonance spectroscopy (MRS). Recently, deep learning (DL) algorithms have found a variety of applications on the process of MRS data. A quantification strategy compatible to DL base MRS spectral processing method is, therefore, useful. MATERIALS AND METHODS: This study aims to investigate whether metabolite concentrations quantified using a convolutional neural network (CNN) based method, coupled with a scaling procedure that normalizes spectral signals for CNN input and linear regression, can effectively reflect variations in metabolite concentrations in IU across different brain regions with varying signal-to-noise ratios (SNR) and linewidths (LW). An error index based on standard error (SE) is proposed to indicate the confidence levels associated with metabolite predictions. In vivo MRS spectra were acquired from three brain regions of 43 subjects using a 3T system. RESULTS: The metabolite concentrations in IU of five major metabolites, quantified using CNN and LCModel, exhibit similar ranges with Pearson's correlation coefficients ranging from 0.24 to 0.78. The SE of the metabolites shows a positive correlation with Cramer-Rao lower bound (CRLB) (r=0.46) and  absolute CRLB (r=0.81), calculated by multiplying CRLBs with the quantified metabolite content. CONCLUSION: In conclusion, the CNN based method with the proposed scaling procedures can be employed to quantify in vivo MRS spectra and derive metabolites concentrations in IU. The SE can be used as error index, indicating predicted uncertainties for metabolites and sharing information similar to the absolute CRLB.

6.
Vascular ; : 17085381231153695, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36690933

RESUMEN

OBJECTIVES: The aim of this study was to report the long-term outcomes of proximal thoracic endovascular aortic repair (TEVAR) for chronic Stanford type B aortic dissection (cTBAD). METHODS: We retrospectively analyzed the clinical data of 48 cases of patients with cTBAD who underwent proximal TEVAR in Zhongshan Hospital Fudan University from January 2010 to September 2013. The preoperative and postoperative imaging examinations, overall survival rate, aortic-related survival rate, and freedom from reintervention rate data were collected to evaluate aortic remodeling and clinical outcomes. The enrolled patients received follow-up at 1, 3, 6, and 12 months following treatment and annually thereafter. RESULTS: A total of 48 patients (mean age, 58.3 ± 10.6 years; men:women, 40:8) were included, of which 38 cases (79.2%) were uncomplicated dissection and 10 cases (20.8%) were complicated. The mean follow-up time was 48.7 ± 40 months (1-120 months). The mean time interval from the initial procedure to reintervention was 50.6 ± 32.7 months (11-98 months). The following changes were observed at preoperative versus last follow-up timepoints. Descending aortic level: true lumen, 19.2 ± 7.01 mm vs. 36.9 ± 9.53 mm (p < 0.001); false lumen, 30.47 ± 15.89 mm vs. 19.16 ± 15.33 mm (p < 0.001); maximum diameter, 49.67 ± 13.96 mm vs. 56.66 ± 14.95 mm (p = 0.018). Diaphragm level: true lumen, 16.24 ± 5.41 mm vs. 24.41 ± 8.04 mm (p < 0.001); false lumen, 12.37 ± 11.49 mm vs. 14.92 ± 12.25 mm (p = 0.196); and maximum diameter, 34 ± 7.81 mm vs. 38.04 ± 7.7 mm (p < 0.001). The freedom from reintervention rate was 81% in 5 years and 50.6% in 10 years. The overall 10-years survival rate was 83% (6 of 48), and the aortic-related survival rate was 92.3% (3 of 48). CONCLUSIONS: TEVAR is a safe and effective proximal repair intervention for cTBAD that can reliably induce the positive remodeling of the descending aorta.

7.
Nano Lett ; 22(8): 3372-3379, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35343229

RESUMEN

Simulation of biological visual perception has gained considerable attention. In this paper, an optoelectrical In2O3 transistor array with a negative photoconductivity behavior is designed using a side-gate structure and a screen-printed ion-gel as the gate insulator. This paper is the first to observe a negative photoconductivity in electrolyte-gated oxide devices. Furthermore, an artificial visual perception system capable of self-adapting to environmental lightness is mimicked using the proposed device array. The transistor device array shows a self-adaptive behavior of light under different levels of light intensity, successfully demonstrating the visual adaption with an adjustable threshold range to the external environment. This study provides a new way to create an environmentally adaptive artificial visual perception system and has far-reaching significance for the future of neuromorphic electronics.


Asunto(s)
Electrólitos , Electrónica , Electrólitos/química , Óxidos
8.
Nano Lett ; 22(2): 545-553, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-34981943

RESUMEN

High-Tc molecular magnets have amassed much promise; however, the long-standing obstacle for its practical applications is the inaccessibility of high-temperature molecular magnets showing dynamic and nonvolatile magnetization control. In addition, its functional durability is prone to degradation in oxygen and heat. Here, we introduce a rapid prototyping and stabilizing strategy for high Tc (360 K) molecular magnets with precise spatial control in geometry. The printed molecular magnets are thermally stable up to 400 K and air-stable for over 300 days, a significant improvement in its lifetime and durability. X-ray magnetic circular dichroism and computational modeling reveal the water ligands controlling magnetic exchange interaction of molecular magnets. The molecular magnets also show dynamical and reversible tunability of magnetic exchange interactions, enabling a colossal working temperature window of 86 K (from 258 to 344 K). This study provides a pathway to flexible, lightweight, and durable molecular magnetic devices through additive manufacturing.

9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(10): 1246-1251, 2023 Oct 10.
Artículo en Zh | MEDLINE | ID: mdl-37730225

RESUMEN

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with rare type heart disease. METHODS: A pedigree identified at Shenzhen Maternity and Child Health Care Hospital Affiliated to Southern Medical University on July 9, 2021 was selected as the study subject. Clinical data were collected. Trio-whole exome sequencing (WES) was carried out for the proband and his parents. Candidate variants were validated by Sanger sequencing of his family members and bioinformatic analysis. RESULTS: The proband, a 5-month-old male, was found to have Barth syndrome (dilated myocardiopathy and left ventricular non-compaction). Trio-WES revealed that he has harbored a hemizygous c.542G>A (p.G181A) variant of the TAZ gene, which was inherited from his mother. In addition, his mother, aunt and maternal grandmother were also found to harbor a c.557G>A (p.R186Q) variant of the TNNI3 gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.542G>A (p.G181A) variant of the TAZ gene was classified as likely pathogenic (PS2_Strong+PM2_Supporting+PP3), whilst the c.557G>A (p.R186Q) variant of the TNNI3 gene was classified as pathogenic (PP1_Strong+PS4_Strong+PP3+PP4+PM2_Supporting). CONCLUSION: The c.542G>A (p.G181A) variant of the TAZ gene probably underlay the Barth syndrome in the proband, and the c.557G>A (p.R186Q) variant of the TNNI3 gene may be responsible for the hypertrophic cardiomyopathy in his mother, aunt and maternal grandmother. Above finding has expanded the mutational spectrum of the TAZ gene and facilitated the diagnosis of this pedigree.


Asunto(s)
Síndrome de Barth , Cardiomiopatía Hipertrófica , Cardiopatías , Femenino , Humanos , Lactante , Masculino , Embarazo , Pueblos del Este de Asia , Linaje
10.
J Environ Sci (China) ; 126: 174-183, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36503747

RESUMEN

It is the key to control bio-derived dissolved organic matters (DOM) in order to reduce the effluent concentration of wastewater treatment, especially for waste leachate with high organic contaminants. In the present study, the anaerobic degradation of aerobically stabilized DOM was investigated with DOM substrate isolated through electrodialysis. The degradation of bio-derived DOM was confirmed by reduction of 15% of total organic carbon in 100 days. We characterized the molecular behavior of bio-derived DOM by coupling molecular and biological information analysis. Venn based Sankey diagram of mass features showed the transformation of bio-derived DOM mass features. Occurrence frequency analysis divided mass features into six categories so as to distinguish the fates of intermediate metabolites and persistent compounds. Reactivity continuum model and machine learning technologies realized the semi-quantitative determination on the kinetics of DOM mass features in the form of pseudo-first order, and confirmed the reduction of inert mass features. Furthermore, network analysis statistically establish relationship between DOM mass features and microbes to identify the active microbes that are able to utilize bio-derived DOM. This work confirmed the biological technology is still effective in controlling recalcitrant bio-derived DOM during wastewater treatment.


Asunto(s)
Materia Orgánica Disuelta , Cinética
11.
Langmuir ; 38(1): 504-513, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34965120

RESUMEN

Optical biosensors support disease diagnostic applications, offering high accuracy and sensitivity due to label-free detection and their optical resonance enhancement. However, optical biosensors based on noble metal nanoparticles and precise micro-electromechanical system technology are costly, which is an obstacle for their applications. Here, we proposed a biosensor reuse method with nanoscale parylene C film, taking the silicon-on-insulator microring resonator biosensor as an example. Parylene C can efficiently adsorb antibody by one-step modification without any surface treatment, which simplifies the antibody modification process of sensors. Parylene C (20 nm thick) was successfully coated on the surface of the microring to modify anti-carcinoembryonic antigen (anti-CEA) and specifically detect CEA. After sensing, parylene C was successfully removed without damaging the sensing surface for the sensor reusing. The experimental results demonstrate that the sensing response did not change significantly after the sensor was reused more than five times, which verifies the repeatability and reliability of the reusable method by using parylene C. This framework can potentially reduce the cost of biosensors and promote their further applications.


Asunto(s)
Técnicas Biosensibles , Silicio , Polímeros , Regeneración , Reproducibilidad de los Resultados , Xilenos
12.
Nano Lett ; 21(22): 9746-9753, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34757755

RESUMEN

Supramolecular engineering bridges molecular assembly with macromolecular charge-transfer salts, promising the design to construct supramolecular architectures that integrate cooperative properties difficult or impossible to find in conventional lattices. Here, we report the crystal engineering design and kinetic growth of one-dimensional supramolecular wires composed of bis(ethylenedithio)tetrathiafulvalene (ET+) cation and polymeric Cu[N(CN)2]2- anion. A bulk ferromagnetic order is discovered for filling up the gap where strong ferromagnetism is missing in such ET molecule-based charge-transfer salts. Metallicity is induced by electric current from the semiconducting wire, which is attributed to strain effect by tuning its close molecular contact. This structural feature is evidenced through the combination of various mechanistic spectroscopic studies. Electric dipole is established from the close molecular contacts and is suggestive to stabilize ferromagnetic spin interaction through anions bridging spin sites. The breakthrough shown here provides a pathway to explore low-dimensional supramolecular materials exhibiting strong electron correlation, metallicity, and ferromagnetism.


Asunto(s)
Electrones , Aniones/química , Cationes , Sustancias Macromoleculares/química
13.
Nano Lett ; 21(16): 6983-6989, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34346219

RESUMEN

Semiconductive metal-organic frameworks (MOFs) obtained by specific host-guest interactions have attracted a large interest in the last two decades, promising development of next-generation electronic devices. Herein, we designed and presented flexible X-ray detectors using Ni-DABDT (DABDT = 2,5-diamino-1,4-benzenedithiol dihydrochloride) MOFs as the absorbing layer. The π-d coupling interactions of Ni-DABDT throughout the framework implement a conspicuous carrier transportation pathway. The detector that converts X-ray photons directly into carriers manifests an attractive achievement with high detection sensitivity of 98.6 µC Gyair-1 cm-2, with a low detection limit of 7.2 µGyair s-1 for the radiation robustness. This work provides insights for next-generation green and high-performance flexible sensor detectors by utilizing MOF materials with the benefits of a designable structure and tunable property, demonstrating a proof-of-concept in wearable X-ray detectors for radiation monitoring and imaging.


Asunto(s)
Estructuras Metalorgánicas , Fotones , Rayos X
14.
Nano Lett ; 21(9): 4099-4105, 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33886320

RESUMEN

Magnetoelectrics are witnessing an ever-growing success toward the voltage-controlled magnetism derived from inorganic materials. However, these inorganic materials have predominantly focused on the ferroelectromagnetism at solid-to-solid interfaces and suffered several drawbacks, including the interface-sensitive coupling mediators, high-power electric field, and limited chemical tunability. Here, we report a promising design strategy to shift the paradigm of next-generation molecular magnetoelectrics, which relies on the integration between molecular magnetism and electric conductivity though an in situ cross-linking strategy. Following this approach, we demonstrate a versatile and efficient synthesis of flexible molecular-based magnetoelectronics by cross-linking of magnetic coordination networks that incorporate conducting chain building blocks. The as-grown compounds feature an improved critical temperature up to 337 K and a room-temperature magnetism control of low-power electric field. It is envisaged that the cross-linking of molecular interfaces is a feasible method to couple and modulate magnetism and electron conducting systems.

15.
Nanotechnology ; 33(11)2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-34875635

RESUMEN

As one of the conductive ink materials with high electric conductivity, elemental copper (Cu) based nanocrystals promise for printable electronics. Here, single crystalline Cu nanoplates were synthesized using a facile hydrothermal method. Size engineering of Cu nanoplates can be rationalized by using the LaMer model and the versatile Cu conductive ink materials are suitable for different printing technologies. The printed Cu traces show high electric conductivity of 6 MS m-1, exhibiting electro-magnetic interference shielding efficiency value of 75 dB at an average thicknesses of 11µm. Together with flexible alumina ceramic aerogel substrates, it kept 87% conductivity at the environmental temperature of 400 °C, demonstrating the potential of Cu conductive ink for high-temperature printable electronics applications.

16.
Ann Vasc Surg ; 72: 237-243, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32891741

RESUMEN

BACKGROUND: The aim of this study was to evaluate the efficacy and safety of a novel self-expanding nitinol stent (Smartflex stent) in femoropopliteal artery obliterans disease. METHODS: From June 2016 to May 2019, patients with atherosclerotic occlusion disease of the superficial femoral and popliteal arteries using the Smartflex stents were retrospectively analyzed in our institution. Patients were monitored at 1, 3, 6, and 12 months and annually thereafter. The main characteristics of the diseased vessels, perioperative and follow-up outcome were evaluated. Kaplan-Meier method was used to assess patency rate and the rate of freedom from clinically driven target lesion revascularization (CD-TLR). RESULTS: A total of 50 limbs from 48 patients (mean age 69.4 ± 8.95 years; 38 men) were included. Eighty-eight Smartflex stents (1.76 stents per limb) were deployed successfully. Of the study patients, 82% had claudication (Rutherford III), 10% had rest pain (Rutherford IV), and 8% had tissue loss (Rutherford V). Trans-Atlantic Inter-Society Consensus II C and D lesions were 26% and 42%, respectively. The mean lesion length was 18.2 ± 8.5 cm and the mean stented length was 22.3 ± 9.9 cm. The average follow-up time was 16.4 ± 8.2 months. Of these lesions, 42 (94%) were chronic total occlusions and 16 (32%) were severely calcified. The primary patency rate at 1 year per Kaplan-Meier estimating, the rate of freedom from CD-TLR at 1 year, and the second patency rate was 83.3%, 88.1%, and 94%, respectively. Among them, 90% patients had improved ankle-brachial indexes (0.47 ± 0.13 before and 0.84 ± 0.16 after). No stent fractures and kinking were identified. CONCLUSIONS: Stenting of the femoropopliteal artery diseases using the Smartflex stent appeared to be safe and effective. It performed well in long-segment and above knee joint lesions.


Asunto(s)
Aleaciones , Arteriosclerosis Obliterante/terapia , Procedimientos Endovasculares/instrumentación , Arteria Femoral , Arteria Poplítea , Stents Metálicos Autoexpandibles , Anciano , Arteriosclerosis Obliterante/diagnóstico por imagen , Arteriosclerosis Obliterante/fisiopatología , Procedimientos Endovasculares/efectos adversos , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/fisiopatología , Diseño de Prótesis , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
17.
Nano Lett ; 20(2): 1110-1116, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31891269

RESUMEN

Light-weight ceramic aerogels hold promise for superinsulation. However, its mechanical instability and complex manufacturing hampered its technical applications. In this study, we demonstrate lightweight pore-gradient ceramic aerogel-like foam monoliths (PGAFoams) through one-pot and in situ bubble supported pore gradient formation. The mechanically strong PGAFoams exhibit a low thermal conductivity of 0.036 W m-1 K-1 and a compressive strength of 89.85 MPa. The pore gradient and integral ceramic monolith nature provides such hydrophobic PGAFoams with thermal management, robust soundproof, and fire-resistance performance. Highly machinable PGAFoams can be adapted into a variety of shapes and dimensions to accommodate complex geometry applications. The scalable manufacturing of lightweight PGAFoams opens up building insulation with remarkable thermal management, high mechanical strength, low mass density, superior soundproofing, and fire-retardant performances.

18.
Nano Lett ; 20(11): 7852-7859, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33054240

RESUMEN

Vertical van der Waals (vdWs) heterostructures based on layered materials are attracting interest as a new class of quantum materials, where interfacial charge-transfer coupling can give rise to fascinating strongly correlated phenomena. Transition metal chalcogenides are a particularly exciting material family, including ferromagnetic semiconductors, multiferroics, and superconductors. Here, we report the growth of an organic-inorganic heterostructure by intercalating molecular electron donating bis(ethylenedithio)tetrathiafulvalene into (Li,Fe)OHFeSe, a layered material in which the superconducting ground state results from the intercalation of hydroxide layer. Molecular intercalation in this heterostructure induces a transformation from a paramagnetic to spin-glass-like state that is sensitive to the stoichiometry of molecular donor and an applied magnetic field. Besides, electron-donating molecules reduce the electrical resistivity in the heterostructure and modify its response to laser illumination. This hybrid heterostructure provides a promising platform to study emerging magnetic and electronic behaviors in strongly correlated layered materials.

19.
Nano Lett ; 20(5): 3828-3835, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32267711

RESUMEN

To exploit the high-temperature superinsulation potential of anisotropic thermal management materials, the incorporation of ceramic aerogel into the aligned structural networks is indispensable. However, the long-standing obstacle to exploring ultralight superinsulation ceramic aerogels is the inaccessibility of its mechanical elasticity, stability, and anisotropic thermal insulation. In this study, we report a recoverable, flexible ceramic fiber-aerogel composite with anisotropic lamellar structure, where the interfacial cross-linking between ceramic fiber and aerogel is important in its superinsulation performance. The resulting ultralight aerogel composite exhibits a density of 0.05 g/cm3, large strain recovery (over 50%), and low thermal conductivity (0.0224 W m-1 K-1), while its hydrophobicity is achieved by in situ trichlorosilane coating with the water contact angle of 135°. The hygroscopic tests of such aerogel composites demonstrate a reversible thermal insulation. The mechanical elasticity and stability of the anisotropic composites, with its soundproof performance, shed light on the low-cost superelastic aerogel manufacturing with scalability for energy saving building applications.

20.
BMC Med Inform Decis Mak ; 20(Suppl 14): 297, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33323108

RESUMEN

BACKGROUND: Medical image data, like most patient information, have a strong requirement for privacy and confidentiality. This makes transmitting medical image data, within an open network, problematic, due to the aforementioned issues, along with the dangers of data/information leakage. Possible solutions in the past have included the utilization of information-hiding and image-encryption technologies; however, these methods can cause difficulties when attempting to recover the original images. METHODS: In this work, we developed an algorithm for protecting medical image key regions. Coefficient of variation is first employed to identify key regions, a.k.a. image lesion areas; then additional areas are processed as blocks and texture complexity is analyzed. Next, our novel reversible data-hiding algorithm embeds lesion area contents into a high-texture area, after which an Arnold transformation is utilized to protect the original lesion information. After this, we use image basic information ciphertext and decryption parameters to generate a quick response (QR) code used in place of original key regions. RESULTS: The approach presented here allows for the storage (and sending) of medical image data within open network environments, while ensuring only authorized personnel are able to recover sensitive patient information (both image and meta-data) without information loss. DISCUSSION: Peak signal to noise ratio and the Structural Similarity Index measures show that the algorithm presented in this work can encrypt and restore original images without information loss. Moreover, by adjusting the threshold and the Mean Squared Error, we can control the overall quality of the image: the higher the threshold, the better the quality and vice versa. This allows the encryptor to control the amount of degradation as, at appropriate amounts, degradation aids in the protection of the image. CONCLUSIONS: As shown in the experimental results, the proposed method allows for (a) the safe transmission and storage of medical image data, (b) the full recovery (no information loss) of sensitive regions within the medical image following encryption, and (c) meta-data about the patient and image to be stored within and recovered from the public image.


Asunto(s)
Algoritmos , Seguridad Computacional , Confidencialidad , Humanos , Tecnología
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