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2.
ACS Appl Mater Interfaces ; 16(14): 17766-17777, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38534058

RESUMEN

Serving as neuromorphic hardware accelerators, memristors play a crucial role in large-scale neuromorphic computing. Herein, two-terminal memristors utilizing amorphous indium-gallium-zinc oxide (a-IGZO) are fabricated through room-temperature sputtering. The electrical characteristics of these memristors are effectively modulated by varying the oxygen flow during the deposition process. The optimized a-IGZO memristor, fabricated under 3 sccm oxygen flow, presents a 5 × 103 ratio between its high- and low-resistance states, which can be maintained over 1 × 104 s with minimal degradation. Meanwhile, desirable properties such as electroforming-free and self-compliance, crucial for low-energy consumption, are also obtained in the a-IGZO memristor. Moreover, analog conductance switching is observed, demonstrating an interface-type behavior, as evidenced by its device-size-dependent performance. The coexistence of negative differential resistance with analog switching is attributed to the migration of oxygen vacancies and the trapping/detrapping of charges. Furthermore, the device demonstrates optical storage capabilities by exploiting the optical properties of a-IGZO, which can stably operate for up to 50 sweep cycles. Various synaptic functions have been demonstrated, including paired-pulse facilitation and spike-timing-dependent plasticity. These functionalities contribute to a simulated recognition accuracy of 90% for handwritten digits. Importantly, a one-selector one-memristor (1S1M) architecture is successfully constructed at room temperature by integrating a-IGZO memristor on a TaOx-based selector. This architecture exhibits a 107 on/off ratio, demonstrating its potential to suppress sneak currents among adjacent units in a memristor crossbar.

3.
World J Pediatr ; 19(4): 323-339, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36534296

RESUMEN

BACKGROUND: This study aimed to analyze the efficacy of resilience-promoting interventions among adolescents and youth aged 10-24 years with any type of diabetes. METHODS: A systematic literature search was performed using the PubMed, Web of Science, Embase, Cochrane Library, CINAHL, and PsycINFO databases from inception to May 25, 2022. The Cochrane risk of bias tool (version 2) was used to assess the quality of the included studies. A meta-analysis was performed to calculate the pooled effects of resilience-promoting interventions. RESULTS: Nineteen articles were included covering an overall sample of 2048 adolescents with diabetes. When analyzing the effectiveness of resilience-promoting interventions, hemoglobin A1c (HbA1c) at six months [mean difference = - 0.47, 95% confidence interval (CI) = - 0.83 to - 0.12, P = 0.009] after the intervention was improved. However, long-term (≥ 12 months) improvement in HbA1c was not significant. In addition, comparing the control group, there were significant differences in the effect size for stress [standardized mean difference (SMD) = - 0.87, 95% CI = - 1.25 to -0.48, P < 0.05], self-efficacy (SMD = 0.50, 95% CI = 0.02-0.98, P = 0.04) and quality of life (SMD = 0.27, 95% CI = 0.03-0.51, P = 0.03). CONCLUSIONS: Resilience-promoting intervention is a promising way for adolescent diabetes management to improve HbA1c, stress, self-efficacy, and quality of life. Incorporating resilience-promoting components into diabetes education and re-enforcing these contents every six months are recommended for implementation in clinical practice.


Asunto(s)
Diabetes Mellitus , Calidad de Vida , Adolescente , Humanos
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 254: 119655, 2021 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-33744702

RESUMEN

Metal-organic framework (MOFs), also known as porous coordination polymers (PCPs), is a new kind of crystalline porous materials, which has received extensive attention in the past few decades. As a new type of sensing material, MOFs stand out from many other traditional fluorescence sensors because of its crystal characteristics, structural diversity, stable porosity and adjustable functional characteristics. In this work, the bi-functional building block containing aromatic carboxylic acid and triazole moieties, namely 3-(1H-1,3,4-triazol-1-yl) benzoic acid, was selected as the linker to synthesize {[Cd(µ5-L)⋅I}n (1, HL = 3-(1H-1,3,4-triazol-1-yl)benzoic acid) by hydrothermal method with transition CdII metal centers. Firstly, the preliminary characterization of 1 was carried out by means of PXRD, FT-IR, and then the UV and fluorescence tests were conducted to study the fluorescence properties of 1. The crystal structure analysis indicates that CdII is the center and the ligand is bridged to form a two-dimensional porous structure. In addition, 1 has good selectivity for Fe3+ and Cr2O72-, meanwhile, it has high detection sensitivity (Ksv quenching efficiency for Fe3+: 1.2 × 104 M-1 and Cr2O72- 1.85 × 104 M-1) and low detection limit (Fe3+: 19.21 µM and Cr2O72-: 12.46 µM). The results of photoluminescence test show that 1 can detect cations and anions with high sensitivity, resist the interference of other ions, and have good reusability. As far as we know, 1 is the first example of ultra-stable two-dimensional (2D) Cadmium (II) microporous coordination material as a fluorescence sensor for Fe3+ and Cr2O72-.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 249: 119214, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33257240

RESUMEN

In industry, over usage of Cu2+ and Al3+ will lead to toxic wastewater, which further to give serious pollution for the environment. On the other hand, L-lysine can enhance serotonin release in the amygdala, with subsequent changes in psychobehavioral responses to stress. Therefore it is the urgent problem to design a method for detecting the amount of Cu2+, Al3+, and L-lysine. In this work, through the solvothermal synthesis method, two new coordination complexes based on the new bifunctional building block 4'-(1H-1,2,4-triazole-1-yl)- [1,1'-biphenyl]-4-carboxylic acid (HL) have been synthesized, namely, [Zn(L)2·4H2O] (complex 1) and [Cd(L)2·4H2O] (complex 2). X-ray single-crystal diffractometer was used to analyze its structure, powder X-ray diffraction (PXRD) patterns confirmed that 1 and 2 powder's purity and 1 can keep stable during the detection process of Cu2+, Al3+, and L-lysine, respectively. Elemental analysis, thermogravimetric analysis, infrared analysis, ultraviolet analysis and fluorescent spectrum have been used to characterize these complexes. The photo-luminescent test showed that 1 can accurately recognize Al3+ and Cu2+ among various cations. On the other hand, 1 can distinguish L-lysine among amino acid molecules. Therefore, 1 can be utilized as a multifunctional fluorescent probe for Al3+(Ksv = 1.5570 × 104 [M]-1), Cu2+(Ksv = 1.4948 × 104 [M]-1) and L-lysine (Ksv = 4.9118 × 104 [M]-1) with low detection limits (17.5 µM, 18.2 µM, 5.6 µM) respectively.


Asunto(s)
Complejos de Coordinación , Cadmio , Cobre , Cristalografía por Rayos X , Lisina , Zinc
6.
Talanta ; 217: 121010, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32498848

RESUMEN

l-histidine acts as a semi-essential amino acid, which is medically used in the treatment of gastric ulcer, anemia, allergies. However, the overuse of l-histidine will result in terrible damage to heart disease, slow growth of animals and water pollution in the environment. In addition, Cu2+ pollution is common environmental pollution in the industry. It has the characteristics of high accumulation, migration, and persistence. Given this, through the post-synthesis strategy, CdTe quantum dots (QDs) were the first time to introduce into zeolitic imidazolate framework-ZIF-365 to synthesis dual-emission hybrid material CdTe@ZIF-365 with high quantum yield. TEM mappings and N2 absorption tests are applied to confirm the combination mode between CdTe quantum dots and ZIF-365. It should be noted that CdTe@ZIF-365 can be successfully utilized as a bi-functional ratiometric sensor for highly sensitive discrimination of l-histidine and Cu2+. Firstly, CdTe@ZIF-365 is applied to a fluorescent ratiometric sensor for Cu2+ with high sensitivity (the Ksv value is 2.7417✕107 [M-1]) and selectivity in the mixed cation ions' solution. On the other hand, CdTe@ZIF-365 also behaved as the first example for an excellent ratiometric fluorescent senor for l-histidine with high sensitivity (the Ksv value is 6.0507✕108 [M-1]) and selectivity in the mixed amino acids' solutions.

7.
Inorg Chem ; 59(5): 2910-2922, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32037805

RESUMEN

Through powerful solvothermal and facile ultrasonic synthetic strategies, two unique cluster-based lanthanide Lu and Y nanoporous metal organic frameworks (MOFs) have been successfully prepared, namely, {[Lu2(L)2]·2DMF·H2O}n (Lu-MOF) and [Y(L)(DMF)0.75]n (Y-MOF) (H3L = terphenyl-3,4'',5-tricarboxylic acid). In addition, both the morphologies and nanosizes of Lu-MOF and Y-MOF materials also have been deliberately tuned by adjustable ultrasonic conditions including irradiation time (40, 60, and 80 min) and power (70 w, 100 w). Currently, it is noted that the abuse of antibiotics such as ornidazole and ronidazole leads to great damage to human health, and therefore the development of highly effective and facile detection methods for ornidazole and ronidazole is quite important. Herein, to improve the fluorescent sensing sensitivity of antibiotics, Eu3+ and Tb3+ have been introduced into Lu-MOF (under a solvothermal preparation method) to fabricate a dual-emission hybrid material Eu3+/Tb3+@Lu-MOF through a postsynthesis strategy, which can be successfully applied as a self-calibrated ratiometric fluorescent sensor for ornidazole and ronidazole with high selectivity and sensitivity (the Ksv value for ornidazole is 1.0854 × 106 [M-1], and the Ksv value for ronidazole is 1.0595 × 107 [M-1]) and low detection limit values (2.85 nM for ornidazole and 26.7 nM for ronidazole). On the other hand, amoeba liver abscess (ALA) will easily lead to irregular fever, night sweats, and other tortured symptoms; C-reactive protein autoantibody (CRP Ab) is the important biomarker for the detection of ALA. Given this, Y-MOF (under the solvothermal preparation method) also has been successfully designed to combine FAM-labeled NH-ssDNA to construct the scarcely reported excellent hybrid FAM-labeled NH-ssDNA/Y-MOF sensing platform for the highly effective discrimination of CRP Ab with excellent sensitivity and selectivity in real samples such as human serum solution.


Asunto(s)
Técnicas Biosensibles , Absceso Hepático Amebiano/diagnóstico por imagen , Estructuras Metalorgánicas/química , Ornidazol/análisis , Ronidazol/análisis , Temperatura , Biomarcadores/análisis , Cristalografía por Rayos X , Fluorescencia , Humanos , Lutecio/química , Estructuras Metalorgánicas/síntesis química , Modelos Moleculares , Estructura Molecular , Tamaño de la Partícula , Solventes/química , Propiedades de Superficie , Ultrasonido , Itrio/química
8.
Biomed Microdevices ; 11(4): 723-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19205887

RESUMEN

A mini-column packed with 1 mg electrospun polystyrene nanofibers (about 200 approximately 400 nm in diameter) was designed for simple, fast extraction of drugs, diazepam and its major metabolite, N-desmethyldiazepam for the analysis of them in human and dog plasma. Ttrezodone was selected as internal standard. The drugs adsorbed on the solid phase could be desorpted with 50 microl of the methanol and then monitored by liquid chromatography coupled to an ultraviolet detector. Parameters influencing the extraction efficiency such as fiber packing amount, eluted solvent, and pH of the sample were decided. The time for the pretreatment of 0.5 ml plasma sample was less than 10 min. The detection limits of diazepam and N-desmethyldiazepam in plasma could be as low as 1 microg/L. The intra- and inter-day precision, calculated from quality control (QC) samples, was less than 9.1%. The method was evaluated by its application in determination of dog plasma samples from three beagles after a single dose oral of diazepam. The technique was validated by comparison with conventional plasma analysis. It was observed that the mini-column offers improved limits of detection and reduced sample preparation time as compared to conventional method. For its simplicity and sensitivity, the method may be used in therapeutic drug monitoring and pharmacology study.


Asunto(s)
Diazepam/análisis , Plasma/química , Extracción en Fase Sólida/instrumentación , Extracción en Fase Sólida/métodos , Animales , Cromatografía Liquida/métodos , Diazepam/aislamiento & purificación , Diazepam/farmacocinética , Perros , Humanos , Sensibilidad y Especificidad , Factores de Tiempo
9.
J Sep Sci ; 31(18): 3272-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18773420

RESUMEN

A novel extraction technique was reported. The solid phase material, nanofiber, was prepared by electrospinning using polystyrene. Twenty different drugs (10 microg/L in water) were extracted using 1 mg of nanofibers within 5 min. The analytes can be desorpted from the fibers with 50 microL of the methanol and then monitored by LC coupled to a UV detector. Packed-fiber SPE (PFSPE) provide high recoveries (>50%) for some relatively non-polar drugs (log P >1.5) (n-octanol-to-water partition ratio), and relatively low recoveries (9.9-39.8%) for the drugs within the log P window below 1. Experimental optimization of the technique has been carried out using seven representative drugs, edaravone, cinchonine, quinine, voriconazole, chlordiazepoxide, verapamil, and rutonding. Except for edaravone, the maximum yields of seven drugs (0.2 microg/L) from water samples were approximately 100%, and were 33.7-88.2% from human plasma. The advantageous aspect of the technique encompasses high throughput, high sensitivity, simplicity, low cost, and green chemistry.


Asunto(s)
Nanoestructuras , Preparaciones Farmacéuticas/aislamiento & purificación , Soluciones Farmacéuticas/química , Extracción en Fase Sólida , Soluciones/química , Agua/química , Tecnología Química Verde/instrumentación , Tecnología Química Verde/métodos , Humanos , Preparaciones Farmacéuticas/análisis , Poliestirenos/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Extracción en Fase Sólida/instrumentación , Extracción en Fase Sólida/métodos
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