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1.
Nanotechnology ; 35(23)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38430571

RESUMEN

In recent times, there has been a notable surge of interests in hafnia (HfO2)-based ferroelectrics, primarily due to their remarkable ferroelectric properties employed in ultra-thin configurations, alongside their compatibility with the conventional CMOS manufacturing process. In order to harness the full potential of HfO2-based films for high-performance non-volatile memory applications, it is imperative to enhance their ferroelectric characteristics and durability. This study introduces a straightforward approach aimed at augmenting the ferroelectric performance of HfxZr1-xO2(HZO) films deposited on silicon (Si) substrates through the engineering of oxygen vacancies (VO). The results of this endeavor demonstrate a significant enhancement in ferroelectric performance, characterized by a 2Pr value of 47µC cm-2and impressive endurance, enduring up to 108cycles under an 8 MV cm-1electric field without the need of a wake-up process. This marked improvement can be attributed to a dual-pronged approach, involving the incorporation of an Al2O3interlayer and the introduction of Al atoms into the HZO film. The Al2O3interlayer primarily serves to mitigate the presence of oxygen vacancies at the interface, while the introduction of Al dopants elevates the concentration of oxygen vacancies within the bulk material. This modulation of oxygen vacancy concentration proves instrumental in facilitating the formation of a ferroelectric o-III phase within the HZO-based films, thereby further augmenting their ferroelectric performance. This innovative and effective strategy offers an alternative avenue for enhancing the ferroelectric properties of materials characterized by a fluorite crystal structure.

2.
Sensors (Basel) ; 24(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38931506

RESUMEN

Within research on the cross-view geolocation of UAVs, differences in image sources and interference from similar scenes pose huge challenges. Inspired by multimodal machine learning, in this paper, we design a single-stream pyramid transformer network (SSPT). The backbone of the model uses the self-attention mechanism to enrich its own internal features in the early stage and uses the cross-attention mechanism in the later stage to refine and interact with different features to eliminate irrelevant interference. In addition, in the post-processing part of the model, a header module is designed for upsampling to generate heat maps, and a Gaussian weight window is designed to assign label weights to make the model converge better. Together, these methods improve the positioning accuracy of UAV images in satellite images. Finally, we also use style transfer technology to simulate various environmental changes in order to expand the experimental data, further proving the environmental adaptability and robustness of the method. The final experimental results show that our method yields significant performance improvement: The relative distance score (RDS) of the SSPT-384 model on the benchmark UL14 dataset is significantly improved from 76.25% to 84.40%, while the meter-level accuracy (MA) of 3 m, 5 m, and 20 m is increased by 12%, 12%, and 10%, respectively. For the SSPT-256 model, the RDS has been increased to 82.21%, and the meter-level accuracy (MA) of 3 m, 5 m, and 20 m has increased by 5%, 5%, and 7%, respectively. It still shows strong robustness on the extended thermal infrared (TIR), nighttime, and rainy day datasets.

3.
Plant Dis ; 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35949188

RESUMEN

Rhododendron pulchrum Sweet is a famous ornamental flower in China. In December 2020, a leaf spot disease was observed on cv. Maojuan in Zhanjiang (21.17 N, 110.18 E), Guangdong, China. The spots were irregular and distributed on both sides of the main vein. They were dark to black, and their borders were obvious. The coalescence of the spots eventually led to leaf wilt. The disease incidence was 100% (n = 100, about 50 ha ). Thirty infected leaves were collected from the field, and the margin of the diseased tissues was cut into 2 mm × 2 mm pieces. Samples were surface disinfected with 75% ethanol and 2% sodium hypochlorite for 30 and 60 s, respectively. They were rinsed thrice with sterile water before isolation. The tissues were plated on potato dextrose agar (PDA) medium and incubated at 28 ℃. After 5 days, fungal colonies appeared on the PDA. Pure cultures were produced by transferring hyphal tips to new PDA plates. Three isolates (RSP-1, RSP-2, and RSP-3) were obtained and the colonies of isolates were preserved in glycerol (15%) at -80 °C deposited at the Museum of Guangdong Ocean University. The morphology of these three isolates was consistent, and their sequences showed 100% homology according to ITS, TEF1, and ACT analysis results. The colonies grew to approximately 5 cm in diameter after 10 days. They showed olive green with off-white aerial mycelia. Stromata and conidia were observed on leaf lesions. Stromata were olivaceous brown. Conidia were solitary, cylindrical to narrowly obclavate, mildly curved, obtuse to rounded at the apex, and 1- to 3-septate; they had dimensions of 20 to 60 × 2.0 to 3.0 µm (n = 30). These morphological characteristics were not different from the description of Pseudocercospora rhododendricola (J.M. Yen) Deighton (Liu et al. 1998). For molecular identification, the colony PCR method with MightyAmp DNA Polymerase (Takara-Bio, Dalian, China) (Lu et al. 2012) was used to amplify the internal transcribed spacer (ITS), translation elongation factor 1-α gene (TEF1), and actin (ACT) loci of the isolates using primer pairs ITS4/ITS5, EF1/EF2, and ACT-512F/ACT-783R, respectively (White et al., 1990; O'Donnell et al. 1997). The sequences of the isolate RSP-1 were deposited in the GenBank (ITS, MW629798; TEF1, MW654168; and ACT, MW654170). BLAST analysis showed that the sequences of P. rhododendricola were submitted to GenBank for the first time by the author of this paper. A phylogenetic tree was generated based on the concatenated data of ITS, TEF1, and ACT sequences from GenBank by the Maximum Likelihood method. The isolates were closest to Pseudocercospora sp. CPC 14711 (Crous et al., 2013). Phylogenetic and morphological analyses identified the isolates as P. rhododendricola. Pathogenicity tests were conducted in a greenhouse at 24 °C-30 â„ƒ with 80% relative humidity. Healthy cv. Maojuan were grown in pots. Unwounded leaflets were inoculated with 5 mm-diameter mycelial plugs of the isolates or agar plugs (as control) (5 leaflets per plant, 3 plants, 2-month-old plants). The test was performed thrice. Disease symptoms were found on the leaves after 2 weeks, whereas the control plants remained healthy. The fungus was re-isolated from the infected leaves and confirmed as the same isolates by morphological and ITS analyses. P. rhododendricola was the cause of leaf spot of Rhododendron sp. from Singapore (Liu et al., 1998). For the first time, this pathogen was identified by combining phylogenetic and morphological analyses. The sequences in this study would be used as the reference sequences for further studies.

4.
Sensors (Basel) ; 21(21)2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34770645

RESUMEN

The reliability and safety of the cascade system, which is widely applied, have attached attention increasingly. Fault detection and diagnosis can play a significant role in enhancing its reliability and safety. On account of the complexity of the double closed-loop system in operation, the problem of fault diagnosis is relatively complex. For the single fault of the second-order valued system sensors, a real-time fault diagnosis method based on data-driven is proposed in this study. Off-line data is employed to establish static fault detection, location, estimation, and separation models. The static models are calibrated with on-line data to obtain the real-time fault diagnosis models. The real-time calibration, working flow and anti-interference measures of the real-time diagnosis system are given. Experiments results demonstrate the validity and accuracy of the fault diagnosis method, which is suitable for the general cascade system.


Asunto(s)
Reproducibilidad de los Resultados , Calibración
5.
Endocr J ; 66(4): 309-317, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-30760653

RESUMEN

Type 2 diabetic patients are becoming younger and having a tendency to family aggregation, they are easily suspected as maturity-onset diabetes of young (MODY) in the outpatient clinic and send to genetic testing. 9 diabetic families were compared in our outpatient clinic who met the primary diagnosis criteria of MODY. Detailed clinical features and laboratory data including gene sequence were collected and analyzed. The patients met the primary clinical diagnostic criteria of MODY for genetic testing at the first look. However, members of families A1 to A3 had normal Body mass index (BMI) and a lower C-peptide level which indicated impaired pancreatic islet function. In contrast, the members with diabetes of families B1 to B6 had normal or increased C-peptide level which indicated insulin resistance and were overweight with BMI. Genetic testing showed that the mutations in HNF1A, INS, KCNJ11 and so on in families A were consistent with the diagnosis of MODY. No pathogenic mutation was found in the members of families B which were diagnosed with familial T2D. Before the clinical laboratory testing and the further gene test, BMI and the concentration of C-peptide are important for the promptly differential diagnosis of MODY from familial type 2 diabetes and medication instruction in the outpatient clinic which could help to alleviate the burden of genetic testing for them.


Asunto(s)
Péptido C/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Adolescente , Adulto , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/genética , Diagnóstico Diferencial , Femenino , Pruebas Genéticas , Factor Nuclear 1-alfa del Hepatocito/genética , Humanos , Masculino , Persona de Mediana Edad , Linaje , Adulto Joven
6.
Sensors (Basel) ; 19(16)2019 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-31426577

RESUMEN

Since the advantages of precise operation and effective reduction of radiation, robots have become one of the best choices for solving the defects of traditional fracture reduction surgery. This paper focuses on the application of robots in fracture reduction surgery, design of the mechanism, navigation technology, robotic control, interaction technology, and the bone-robot connection technology. Through literature review, the problems in current fracture reduction robot and its future development are discussed.


Asunto(s)
Fracturas Óseas/cirugía , Robótica , Fijación de Fractura , Humanos , Cirugía Asistida por Computador/métodos
7.
Eur J Med Chem ; 241: 114621, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-35931006

RESUMEN

Although multivalent glucosidase inhibitors based on iminosugars have shown enhanced inhibition activity, an effective way to improve their hypoglycemic effect in vivo, is still in infancy and needs further development. In this paper, PBI-5DNJ and PBI-6DNJ, with three or four DNJ moieties respectively conjugated at the bay position were synthesized. PBI-6DNJ evidenced stronger π-π stacking interactions and, when self-assembled, a smaller size than that of PBI-5DNJ. It was found that PBI-6DNJ exhibited superior α-glucosidases (from mice) inhibition activity (Ki = 0.14 ± 0.007 µM) in vitro than that (Ki = 0.31 ± 0.01) of PBI-5DNJ and in vivo hypoglycemic effects in mice models. PBI-6DNJ possessed good hypoglycemic effects with the percentages of PBG levels of 40.40 ± 3.33% and 39.23 ± 4.84% at a dose of 2.0 mg/kg after 15 min and 30 min of administration, respectively. In terms of measuring percentage decrease of PBG level per DNJ unit, PBI-6DNJ displayed a 2.1-fold enhancement than miglitol, demonstrating a consistency between in vitro and in vivo experiments. This paves the way to the connection between in vivo hypoglycemic potency and in vitro glucosidase inhibition assay, leading to reliable and simplified assessment of hypoglycemic potency determination, and opening a basic understanding of the design of multivalent glucosidase inhibitors.


Asunto(s)
Imidas , Perileno , Animales , Inhibidores Enzimáticos/farmacología , Hipoglucemiantes/farmacología , Ratones , Perileno/análogos & derivados , alfa-Glucosidasas
8.
Polymers (Basel) ; 13(19)2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34641077

RESUMEN

In this paper, a basalt fiber surface was treated with coupling agent KH-550 and hydrochloric acid, and the basalt fiber polymer-modified active powder concrete (RPC) material was prepared. There are significant differences in material composition and properties between basalt fiber polymer-modified RPC and ordinary concrete, and the structural design calculation (cracking moment and normal section bending bearing capacity) of an ordinary reinforced concrete beam is no longer applicable. Thus, mechanical parameters such as displacement and strain of reinforcement basalt fiber polymer-modified RPC beams subjected to four-point bending were tested. The excellent compressive and tensile strengths of basalt fiber polymer-modified RPC were fully utilized. The tensile strength of basalt fiber polymer-modified RPC in the tensile zone of the beam was considered in the calculation of normal section bending bearing capacity of reinforcement basalt fiber polymer-modified RPC beams. The results showed that the measured values of the cracking moment and ultimate failure bending moment of reinforcement basalt fiber polymer-modified RPC beams were in good agreement with the calculated values. The established formulas for cracking moment and normal section bending bearing capacity can provide references for the design of reinforcement basalt fiber polymer-modified RPC simply supported beam and promote the wide application of basalt fiber polymer-modified RPC materials in practical engineering.

9.
IEEE Trans Cybern ; 51(11): 5423-5432, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31905157

RESUMEN

In this article, a multiscale generative adversarial network (MS-GAN) is proposed for generating high-quality crowd density maps of arbitrary crowd density scenes. The task of crowd counting has many challenges, such as severe occlusions in extremely dense crowd scenes, perspective distortion, and high visual similarity between the pedestrians and background elements. To address these problems, the proposed MS-GAN combines a multiscale convolutional neural network (generator) and an adversarial network (discriminator) to generate a high-quality density map and accurately estimate the crowd count in complex crowd scenes. The multiscale generator utilizes the fusion features from multiple hierarchical layers to detect people with large-scale variation. The resulting density map produced by the multiscale generator is processed by a discriminator network trained to solve a binary classification task between a poor quality density map and real ground-truth ones. The additional adversarial loss can improve the quality of the density map, which is critical to accurately estimate the crowd counts. The experiments were conducted on multiple datasets with different crowd scenes and densities. The results showed that the proposed method provided better performance compared to current state-of-the-art methods.

10.
Chem Commun (Camb) ; 57(22): 2776-2779, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33596281

RESUMEN

A mannose-modified perylene monoimide derivative PMI-Man was developed, which shows highly selective binding to double-stranded DNA molecules, potent live/dead cell imaging, and histological imaging via both confocal and light microscopies. This approach can be used to develop a universal colorful staining method for human tissues for both confocal and light microscopies.


Asunto(s)
ADN/análisis , Perileno/química , Línea Celular , Humanos , Microscopía Confocal , Análisis Espectral/métodos
11.
J Med Chem ; 64(9): 5863-5873, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33886333

RESUMEN

Although multivalent glycosidase inhibitors have shown enhanced glycosidase inhibition activities, further applications and research directions need to be developed in the future. In this paper, two positional isomeric perylene bisimide derivatives (PBI-4DNJ-1 and PBI-4DNJ-2) with 1-deoxynojirimycin conjugated were synthesized. Furthermore, PBI-4DNJ-1 and PBI-4DNJ-2 showed positional isomeric effects on the optical properties, self-assembly behaviors, glycosidase inhibition activities, and hypoglycemic effects. Importantly, PBI-4DNJ-1 exhibited potent hypoglycemic effects in mice with 41.33 ± 2.84 and 37.45 ± 3.94% decreases in blood glucose at 15 and 30 min, respectively. The molecular docking results showed that the active fragment of PBI-4DNJ-1 has the highest binding energy (9.649 kcal/mol) and the highest total hydrogen bond energy (62.83 kJ/mol), which were related to the positional isomeric effect on the hypoglycemic effect in mice. This work introduced a new means to develop antihyperglycemic agents in the field of multivalent glycomimetics.


Asunto(s)
Glucosamina/análogos & derivados , Glicósido Hidrolasas/metabolismo , Hipoglucemiantes/química , Imidas/química , Perileno/análogos & derivados , Administración Oral , Animales , Sitios de Unión , Glucemia/análisis , Glucosamina/química , Glicósido Hidrolasas/antagonistas & inhibidores , Enlace de Hidrógeno , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/metabolismo , Isomerismo , Cinética , Ratones , Conformación Molecular , Simulación del Acoplamiento Molecular , Perileno/química , Unión Proteica , Termodinámica
12.
J Mater Chem B ; 7(9): 1379-1383, 2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-32255008

RESUMEN

A novel supramolecular multivalent glycosidase inhibitor was constructed based on the amphiphilic deoxynojirimycin derivative FA-DNJ. FA-DNJ self-assembled into spherical assemblies with the diameters between 103 nm and 137 nm under different pH values (pH 2-7) and showed a potent glycosidase effect against α-mannosidase with a Ki value of 0.11 µM, an effect that increased approximately 330-fold compared with that of miglitol. In addition, FA-DNJ exhibited a hypoglycaemic effect in mice.


Asunto(s)
Inhibidores Enzimáticos/química , Ácidos Grasos/química , Glucosamina/análogos & derivados , Hipoglucemiantes/química , alfa-Manosidasa/antagonistas & inhibidores , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/química , 1-Desoxinojirimicina/metabolismo , Animales , Glucemia/análisis , Supervivencia Celular/efectos de los fármacos , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Glucosamina/química , Prueba de Tolerancia a la Glucosa , Concentración de Iones de Hidrógeno , Hipoglucemiantes/metabolismo , Hipoglucemiantes/farmacología , Maltosa/administración & dosificación , Ratones , alfa-Manosidasa/metabolismo
13.
J Mater Chem B ; 7(8): 1270-1275, 2019 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-32255166

RESUMEN

A self-assembled multivalent glycosidase inhibitor based on perylene bisimide-deoxynojirimycin conjugates was constructed, inhibited α-mannosidase and exhibited a Ki value of 38 nM, increased approximately 2763-fold compared with the control drug (miglitol). Furthermore, the postprandial blood glucose (PBG) level in mice of PBI-DNJ was firstly studied. PBI-DNJ exhibited a hypoglycaemic effect in vivo. Importantly, this work developed a new means to explore the hypoglycaemic effect in mice based on self-assembled glycosidase inhibitors.


Asunto(s)
Glucosamina/análogos & derivados , Glicósido Hidrolasas/antagonistas & inhibidores , Imidas/metabolismo , Perileno/análogos & derivados , 1-Desoxinojirimicina/metabolismo , Animales , Glucosamina/metabolismo , Humanos , Ratones , Perileno/metabolismo
14.
Cell Mol Neurobiol ; 28(5): 745-55, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17647101

RESUMEN

The Xiaoyaosan (XYS) decoction, a Chinese traditional prescription containing eight commonly used herbs, has been used for treatment of mental disorders such as depression for centuries in China. However, the mechanism underlying its antidepressant activity is poorly understood. In rats with chronic immobilization stress (CIS), we examined the effects of the XYS decoction on tail suspension behavior and the levels of brain-derived neurotrophic factor (BDNF), tyroxine hydroxylase (TrkB), and neurotrophin 3 (NT-3) in the frontal cortex and hippocampus. Rats subjected to CIS exhibited decreases in weight-gain, food intake, and ambulation in the open field test; they also showed an increase in immobility in the tail suspension test. These were all attenuated by the XYS decoction. Biochemically, the XYS decoction also reversed CIS-induced decreases in BDNF and increases in TrkB and NT-3 in the frontal cortex and the hippocampal CA(1) subregion. The behavioral effects of the XYS were correlated to the biochemical actions. These results suggest that the XYS decoction produces an antidepressant-like effect, which appears to be involved by BDNF in the brain.


Asunto(s)
Antidepresivos/farmacología , Encéfalo/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Factores de Crecimiento Nervioso/efectos de los fármacos , Estrés Psicológico/tratamiento farmacológico , Animales , Antidepresivos/uso terapéutico , Regulación del Apetito/efectos de los fármacos , Regulación del Apetito/fisiología , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Encéfalo/metabolismo , Encéfalo/fisiopatología , Factor Neurotrófico Derivado del Encéfalo/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Enfermedad Crónica/terapia , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/fisiología , Medicamentos Herbarios Chinos/uso terapéutico , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Factores de Crecimiento Nervioso/metabolismo , Neurotrofina 3/efectos de los fármacos , Neurotrofina 3/metabolismo , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor trkB/efectos de los fármacos , Receptor trkB/metabolismo , Restricción Física/psicología , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Resultado del Tratamiento , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología
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