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1.
Sensors (Basel) ; 19(7)2019 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-30934719

RESUMEN

Hypertension is one of the most common cardiovascular diseases, which will cause severe complications if not treated in a timely way. Early and accurate identification of hypertension is essential to prevent the condition from deteriorating further. As a kind of complex physiological state, hypertension is hard to characterize accurately. However, most existing hypertension identification methods usually extract features only from limited aspects such as the time-frequency domain or non-linear domain. It is difficult for them to characterize hypertension patterns comprehensively, which results in limited identification performance. Furthermore, existing methods can only determine whether the subjects suffer from hypertension, but they cannot give additional useful information about the patients' condition. For example, their classification results cannot explain why the subjects are hypertensive, which is not conducive to further analyzing the patient's condition. To this end, this paper proposes a novel hypertension identification method by integrating classification and association rule mining. Its core idea is to exploit the association relationship among multi-dimension features to distinguish hypertensive patients from normotensive subjects. In particular, the proposed method can not only identify hypertension accurately, but also generate a set of class association rules (CARs). The CARs are proved to be able to reflect the subject's physiological status. Experimental results based on a real dataset indicate that the proposed method outperforms two state-of-the-art methods and three common classifiers, and achieves 84.4%, 82.5% and 85.3% in terms of accuracy, precision and recall, respectively.


Asunto(s)
Lechos , Minería de Datos/métodos , Hipertensión/patología , Adulto , Anciano , Algoritmos , Balistocardiografía/instrumentación , Balistocardiografía/métodos , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Hipertensión/clasificación , Masculino , Sistemas Microelectromecánicos , Persona de Mediana Edad , Análisis de Ondículas
2.
Chem Pharm Bull (Tokyo) ; 64(1): 21-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26726741

RESUMEN

The coacervation between gelatin and sodium alginate for ginger volatile oil (GVO) microencapsulation as functions of mass ratio, pH and concentration of wall material and core material load was evaluated. The microencapsulation was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), and thermal gravimetric analysis (TGA). SEM and FT-IR studies indicated the formation of polyelectrolyte complexation between gelatin and sodium alginate and successful encapsulation of GVO into the microcapsules. Thermal property study showed that the crosslinked microparticles exhibited higher thermal stability than the neat GVO, gelatin, and sodium alginate. The stability of microencapsulation of GVO in a simulated gastric and an intestinal situation in vitro was also studied. The stability results indicated that the release of GVO from microcapsules was much higher in simulated intestinal fluid, compared with that in simulated-gastric fluid.


Asunto(s)
Alginatos/química , Cápsulas/química , Electrólitos/química , Gelatina/química , Aceites Volátiles/química , Polímeros/química , Zingiber officinale/química , Composición de Medicamentos , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Propiedades de Superficie
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 46(5): 702-5, 725, 2015 Sep.
Artículo en Zh | MEDLINE | ID: mdl-26619539

RESUMEN

OBJECTIVE: To determine the effect of chronic intermittent hypoxia on cognitive function and prefrontal cortex neurons in rats. METHODS: 48 adult male Wistar rats were randomly divided into two groups: control group and 50 mL/L intermittent hypoxia group (50 mL/L CIH). Rats in the CIH group were placed in the low oxygen tank, simulating intermittent hypoxia environment. At 7 d, 14 d, 21 d, and 28 d, the learning and memory ability of the rats was assessed with the Morris water maze (MWM) test; the expressions of cysteinyl aspartate specific protease (caspase)-8 protein in their prefrontal cortex were determined using Western blot method; the apoptosis of neurons was detected by the TdT mediated UTP nick end labeling (TUNEL) method. RESULTS: Compared with the controls, the CIH rats had significantly prolonged escape latency at 14 d, 21 d, and 28 d (P<0. 05) and decreased target quadrant time (P<0. 05). The prolonged escape latency increased and target quadrant time shortened with length of exposure to hypoxia (P<0. 05). Compared with controls, the CIH rats had gradually increased caspase-8 in their frontal cortex neurons, peaked at 28 d (P<0. 05). The CIH rats showed obvious structural damage and reduced neuron density in their frontal cortex neurons. They had higher levels of nerve cell apoptosis (P<0. 05), with apoptosis index increasing with length of exposure to hypoxia (P<0. 05). CONCLUSION: Severe chronic intermittent hypoxia can lead to pathological changes of frontal,cortex of rats, possibly


Asunto(s)
Cognición , Hipoxia , Neuronas/citología , Corteza Prefrontal/patología , Animales , Apoptosis , Masculino , Memoria , Corteza Prefrontal/citología , Ratas , Ratas Wistar
4.
Nanotechnology ; 25(10): 105705, 2014 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-24531012

RESUMEN

We demonstrate that high-quality vertically aligned SnSe nanorod (NR) arrays have been synthesized via a facile chemical vapor deposition method on SiO2 substrates using Bi powder as catalysts. Both SEM and TEM measurements reveal that this kind of SnSe NR consists of a one-dimensional core and dense two-dimensional branches. Thermistors and photoresistors have been fabricated in situ by directly depositing silver paint on the growth substrates. The thermistor shows the great merits of a broad temperature range (77-390 K), linear input-output characteristic, suitable thermal index and high sensitivity. The photoresistor device exhibits relatively fast response time, linear input-output, high reversibility and stability. In addition, both of the devices have the advantages of low cost, environment-friendliness and easy fabrication. The high performance of SnSe thermistors and photodetectors will make SnSe material promising in industrial multi-function nanodevices.

5.
Zhonghua Jie He He Hu Xi Za Zhi ; 37(11): 840-4, 2014 Nov.
Artículo en Zh | MEDLINE | ID: mdl-25604115

RESUMEN

OBJECTIVE: To explore the effect of mitochondrial autophagy on cognitive function in rats of early intermittent hypoxia by observing hippocampal CA1 pyramidal cell mitochondrial autophagy and the expression of related proteins in a intermittent hypoxia(IH) animal model. METHODS: Seventy-two adult male Wistar rats were randomly divided into a control group (UC) and a 5% intermittent hypoxia (IH) group. The compressed air was given to the UC group while rats in 5% IH group suffered from 7-hour IH every day. At 1 d, 3 d, 5 d, 7 d, 10 d and 14 d after the completion of the model, transmission electron microscopy was used to observation rat hippocampal CA1 pyramidal cell mitochondrial ultrastructural changes, and immunohistochemistry assay was used to detect the expression of Beclin-1 and LC3. The Morris water test was performed to detect the learning and memory function in the rats. RESULTS: Compared with the UC group, the 5% IH group began to show mitochondrial size and shape changes, swelling, reduced matrix density, cristae, mitochondrial vacuolization, and typical mitochondria autophagosome formation from the 3 d. In the 5% IH group, Beclin-1 and LC3 protein expressions were significantly increased compared with the UC group (P < 0.05). The expressions of Beclin-1 and LC3were different among different time points (P < 0.05); with the extension of time, their expressions firstly increased, peaked at 10 d (P < 0.05), and then decreased at 14 d (P < 0.05). Their expressions in the UC group were not different significantly among different time points (P > 0.05). The level of learning and memory of the rats in the 5% IH group had no obvious changes compared with the UC group at 1 d, 3 d, 5 d, 7 d, and 10 d, but the level started to drop at 14 d with a significant difference (P < 0.05) . The level of learning and memory of the rats in the UC group was not different among different time points (P > 0.05). CONCLUSION: Early intermittent hypoxia induced hippocampus mitochondrial autophagy and autophagy-related protein expression in rats. Mitochondrial autophagy may reduce the damage to cognitive function of the rats exposed to early intermittent hypoxia.


Asunto(s)
Cognición , Hipoxia , Animales , Autofagia , Modelos Animales de Enfermedad , Hipocampo , Masculino , Memoria , Mitocondrias , Ratas , Ratas Wistar
6.
Tree Physiol ; 43(3): 452-466, 2023 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-36263985

RESUMEN

A cultivable endophytic fungus, Piriformospora indica, improves growth and enhances stress tolerance of host plants, but the underlying mechanisms remain unknown. We hypothesized that P. indica enhanced the drought tolerance of the host by regulating the antioxidant defense system and composition of fatty acids. Trifoliate orange (Poncirus trifoliata) seedlings were inoculated with P. indica under ample water and drought stress to analyze the change in plant growth, reactive oxygen species (ROS) levels, antioxidant enzyme activities, non-enzymatic antioxidant concentrations, fatty acid compositions, and expressions of both antioxidant enzyme genes and fatty acid desaturase (FAD) genes. The 9-week soil water deficit significantly increased the colonization of P. indica to roots, and P. indica promoted the increase of shoot biomass under drought. Soil drought triggered an elevation of hydrogen peroxide in roots, while the inoculated plants had lower levels of ROS (hydrogen peroxide and superoxide anion radicals) and lower degree of membrane lipid peroxidation (based on malondialdehyde levels) under drought. Drought treatment also elevated ascorbic acid and glutathione concentrations, and the elevation was further amplified after P. indica inoculation. Inoculated plants under drought also recorded significantly higher iron-superoxide dismutase (Fe-SOD), manganese-superoxide dismutase (Mn-SOD), peroxidases, catalase, glutathione reductase and ascorbate peroxidase activities, accompanied by up-regulation of PtFe-SOD and PtCu/Zn-SOD expressions. Inoculation with P. indica significantly increased total saturated fatty acids (e.g., C6:0, C15:0, C16:0, C23:0 and C24:0) concentration and reduced total unsaturated fatty acids (e.g., C18:1N9C, C18:2N6, C18:3N3, C18:1N12 and C19:1N9T) concentrations, leading to a decrease in the unsaturation index of fatty acids, which may be associated with the up-regulation of PtFAD2 and PtFAD6 and down-regulation of PtΔ9. It was concluded that the colonization of P. indica can activate enzyme and non-enzyme defense systems and regulate the composition of fatty acids under drought, thus alleviating the oxidative damage to the host caused by drought.


Asunto(s)
Basidiomycota , Poncirus , Antioxidantes/metabolismo , Poncirus/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Resistencia a la Sequía , Peróxido de Hidrógeno/metabolismo , Ácidos Grasos/metabolismo , Basidiomycota/fisiología , Superóxido Dismutasa/metabolismo , Sequías , Agua/metabolismo
7.
ISA Trans ; 141: 84-92, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37451919

RESUMEN

While threats from outsiders are easier to alleviate, effective ways seldom exist to handle threats from insiders. The key to managing insider threats lies in engineering behavioral features efficiently and classifying them correctly. To handle challenges in feature engineering, we propose an integrated feature engineering solution based on daily activities, combining manually-selected features and automatically-extracted features together. Particularly, an LSTM auto-encoder is introduced for automatic feature engineering from sequential activities. To improve detection, a residual hybrid network (ResHybnet) containing GNN and CNN components is also proposed along with an organizational graph, taking a user-day combination as a node. Experimental results show that the proposed LSTM auto-encoder could extract hidden patterns from sequential activities efficiently, improving F1 score by 0.56%. Additionally, with the designed residual link, our ResHybnet model works well to boost performance and has outperformed the best of other models by 1.97% on the same features. We published our code on GitHub: https://github.com/Wayne-on-the-road/ResHybnet.

8.
Health Inf Sci Syst ; 11(1): 8, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36721639

RESUMEN

Wireless body area network (WBAN) is widely adopted in healthcare services, providing remote real-time and continuous healthcare monitoring. With the massive increase of detective sensor data, WBAN is largely restricted by limited storage and computation capacity, resulting in severely decreased efficiency and reliability. Mobile edge computing (MEC) technique can be combined with WBAN to resolve this issue. This paper studies the joint optimization problem of computational offloading and resource allocation (JCORA) in MEC for healthcare service scenarios. We formulate JCORA as a Markov decision process and propose a deep deterministic policy gradient-based WBAN offloading strategy (DDPG-WOS) to optimize time delay and energy consumption in interfered transmission channels. This scheme employs MEC to mitigate the computation pressure on a single WBAN and increase the transmission ability. Further, DDPG-WOS optimizes the offloading strategy-making process by considering the channel condition, transmission quality, computation ability and energy consumption. Simulation results verify the effectiveness of the proposed optimization schema in reducing energy consumption and computation latency and increasing the utility of WBAN compared to two competitive solutions.

9.
Front Plant Sci ; 14: 1247342, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37860240

RESUMEN

Soil drought is detrimental to plant growth worldwide, particularly by triggering reactive oxygen species (ROS) burst. Serendipita indica (Si), a culturable root-associated endophytic fungus, can assist host plants in dealing with abiotic stresses; however, it is unknown whether and how Si impacts the drought tolerance of citrus plants. To unravel the effects and roles of Si on drought-stressed plants, trifoliate orange (Poncirus trifoliata L. Raf.; a citrus rootstock) seedlings were inoculated with Si and exposed to soil drought, and growth, gas exchange, ROS levels, antioxidant defense systems, and expression of genes encoding antioxidant enzymes and fatty acid desaturases in leaves were measured. Soil drought suppressed plant biomass, whereas Si inoculation significantly increased plant biomass (10.29%-22.47%) and shoot/root ratio (21.78%-24.68%) under ample water and drought conditions, accompanied by improved net photosynthetic rate (105.71%), water use efficiency (115.29%), chlorophyll index (55.34%), and nitrogen balance index (63.84%) by Si inoculation under soil drought. Soil drought triggered an increase in leaf hydrogen peroxide and superoxide anion levels, while Si inoculation significantly reduced these ROS levels under soil drought, resulting in lower membrane lipid peroxidation with respect to malondialdehyde changes. Furthermore, Si-inoculated seedlings under soil drought had distinctly higher levels of ascorbate and glutathione, as well as catalase, peroxidase, and glutathione peroxidase activities, compared with no-Si-inoculated seedlings. Si inoculation increased the expression of leaf PtFAD2, PtFAD6, PtΔ9, PtΔ15, PtFe-SOD, PtCu/Zn-SOD, PtPOD, and PtCAT1 genes under both ample water and soil drought conditions. Overall, Si-inoculated trifoliate orange plants maintained a low oxidative burst in leaves under drought, which was associated with stimulation of antioxidant defense systems. Therefore, Si has great potential as a biostimulant in enhancing drought tolerance in plants, particularly citrus.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 500-4, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22512198

RESUMEN

In the present study, sucrose was used as a chiral selector to detect the molar fraction of R-metalaxyl and S-ibuprofen due to the UV spectral difference caused by the interaction of the R- and S-isomer with sucrose. The quantitative model of the molar fraction of R-metalaxyl was established by partial least squares (PLS) regression and the robustness of the models was evaluated by 6 independent validation samples. The determination coefficient R2 and the standard error of calibration set (SEC) was 99.98% and 0.003 respectively. The correlation coefficient of estimated value and specified value, the standard error and the relative standard deviation (RSD) of the independent validation samples was 0.999 8, 0.000 4 and 0.054% respectively. The quantitative models of the molar fraction of S-ibuprofen were established by PLS and the robustness of models was evaluated. The determination coefficient R2 and the standard error of calibration set (SEC) was 99.82% and 0.007 respectively. The correlation coefficient of estimated value and specified value of the independent validation samples was 0.998 1. The standard error of prediction (SEP) was 0.002 and the relative standard deviation (RSD) was 0.2%. The result demonstrates that sucrose is an ideal chiral selector for building a stable regression model to determine the enantiomeric composition.


Asunto(s)
Análisis de los Mínimos Cuadrados , Preparaciones Farmacéuticas , Análisis Espectral , Alanina/análogos & derivados , Calibración , Estereoisomerismo , Sacarosa
11.
Front Microbiol ; 13: 967851, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35979492

RESUMEN

Ascorbate-glutathione cycle is an important pathway for plants to scavenge reactive oxygen species (ROS) under environmental stress conditions. The objective of this study was to investigate the effects of the endophytic fungus Serendipita indica on biomass, chlorophyll concent, ROS levels, antioxidant enzyme activities, and ascorbate-glutathione cycle in white clover under ample water and water stress conditions. The results showed that 46 days of soil water stress distinctly promoted root colonization by S. indica. Under water stress, S. indica inoculation significantly promoted shoot and root biomass, total chlorophyll content, and activities of superoxide dismutases (SOD; e.g., Fe-SOD and Cu/Zn-SOD) and peroxidase in roots, coupled with a decrease in malondialdehyde content in roots. In the ascorbate-glutathione cycle of roots, S. indica also significantly increased the activity of ascorbate peroxidase and glutathione reductase activities in water-stressed white clover, along with the increase in reduced ascorbic acid and reduced/oxidized glutathione contents, thus accelerating the ascorbate-glutathione cycle in inoculated plants to scavenge more ROS (e.g., hydrogen peroxide). As a result, S. indica enhanced the tolerance of white clover in response to water stress by enhancing antioxidant enzyme activities and accelerating the ascorbate-glutathione cycle.

12.
IEEE Trans Cybern ; 51(10): 4808-4821, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33147158

RESUMEN

Data privacy and utility are two essential requirements in outsourced data storage. Traditional techniques for sensitive data protection, such as data encryption, affect the efficiency of data query and evaluation. By splitting attributes of sensitive associations, database fragmentation techniques can help protect data privacy and improve data utility. In this article, a distributed memetic algorithm (DMA) is proposed for enhancing database privacy and utility. A balanced best random distributed framework is designed to achieve high optimization efficiency. In order to enhance global search, a dynamic grouping recombination operator is proposed to aggregate and utilize evolutionary elements; two mutation operators, namely, merge and split, are designed to help arrange and create evolutionary elements; a two-dimension selection approach is designed based on the priority of privacy and utility. Furthermore, a splicing-driven local search strategy is embedded to introduce rare utility elements without violating constraints. Extensive experiments are carried out to verify the performance of the proposed DMA. Furthermore, the effectiveness of the proposed distributed framework and novel operators is verified.

13.
J Org Chem ; 75(11): 3663-70, 2010 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-20450219

RESUMEN

Enantioselective acylation catalyzed by the thioamide modified 1-methylhistidine methyl ester 1 in combination with DABCO-mediated racemization of the substrate led to the efficient dynamic kinetic resolution of meso-1,2-diol monodichloroacetates. In this way, cyclic and acyclic meso-1,2-diol monodichloroacetates can be transformed to the enantiomerically enriched (1S,2R)-heterosubstituted diol diesters which are stable in enantiomerically pure form and can be readily used for further organic transformations.

14.
ACS Appl Mater Interfaces ; 6(4): 2878-83, 2014 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-24467167

RESUMEN

For highly efficient photoelectrodes, the materials used must have both a broad absorption range and large separation efficiency of photogenerated electron-hole pairs. Type II heterostructures with a ternary shell meet these two requirements and thus are recognized as being an ideal materials system for application in photocatalytic hydrogen production. Here, a ZnO/ZnxCd1-xTe core/shell nanowires array with a broad absorption edge from UV (380 nm) to NIR (855 nm) was fabricated via a chemical vapor-deposition method. More importantly, the ZnO/ZnxCd1-xTe core/shell nanowires array are highly single crystalline, and the composition can be continuously tuned by optimizing the deposition temperature, making the design of the desired photocatalyst possible. As expected, the single-crystalline ternary ZnxCd1-xTe shell greatly enhances the charge separation efficiency and prolongs the lifetime of photogenerated charge carriers, which contribute to the high photocatalytic and photoelectrocatalytic activity under light irradiation. In addition, ZnO/ZnxCd1-xTe core/shell structure show remarkable photocatalytic H2-production activity and high H2-production capability because of the synergistic light absorption of the ternary ZnxCd1-xTe shell and the formation of a type II heterostructure at the interface between the ZnO core and ZnxCd1-xTe shell. This work provides a new material platform for the design of highly efficient solar-fuel devices that demonstrate a broad and controllable absorption from the UV to NIR wavelengths.

15.
J Chromatogr Sci ; 52(10): 1317-25, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24363270

RESUMEN

In this paper, a simple and efficient approach, directly suspended droplet microextraction (DSDME), has been applied to extract aroma components in Chinese southwest tobacco prior to analysis by gas chromatography-mass spectrometry (GC-MS). The extraction parameters such as organic solvent type, extraction time, temperature, stirring speed and volume were systemically optimized. A single drop of cyclohexane was placed on the top of the aqueous sample which was used as solvent. Under the optimal conditions of DSDME, 62 aroma components of tobacco were analyzed and identified by GC-MS. The approach was used to determine some important aromas in tobacco with the relative recoveries ranged from 75.92 to 102.88%, relative standard deviations in the range of 3.40-7.14% (n = 5) and the limits of detection of 0.0002-0.002 µg/mL. Moreover, the DSDME was applied to identify the aromatic components in Chinese southwest tobacco in this research for the first time and the results suggested that the method can be used as rapid determination of the tobacco. This method can enhance the extracting rate of tobacco aromatic components and meet the need of qualitative analysis of large amount samples.


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Nicotiana/química , Odorantes/análisis , Ciclohexanos/química , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
16.
Org Lett ; 15(15): 3856-9, 2013 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-23869658

RESUMEN

In refluxing water and without an additional catalyst, electron-rich phenols could react with alkynoic acids or alkynoates to provide coumarin structures. The skeletons of two natural pyranocoumarins, 5-methoxyseselin and alloxanthoxyletin, could be constructed (total yield up to 76%) in an aqueous multicomponent reaction in which isoprenyl acetate, propiolic acid, and phloroglucinol were simply mixed and refluxed in water.

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