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1.
Adv Mater ; 36(32): e2403905, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38806154

RESUMO

Boosting stretchability and electric output is critical for high-performance wearable triboelectric nanogenerators (TENG). Herein, for the first time, a new approach for tuning the composition of surface functional groups through surfactant self-assembly to improve the tribopositivity, where the assembly increases the transferred charge density and the relative permittivity of water polyurethane (WPU). Incorporating bis(trifluoromethanesulfonyl)imide (TFSI-) and alkali metal ions into a mixture of WPU and the surfactant forms a stretchable film that simultaneously functions as positive tribolayer and electrode, preventing the conventional detachment of tribolayer and electrode in long term usage. Further, the conductivity of the crosslinked film reaches 3.3 × 10-3 mS cm-1 while the elongation at break reaches 362%. Moreover, the surfactant self-assembly impedes the adverse impact of the fluorine-containing groups on tribopositivity. Consequently, the charge density reaches 155 µC m-2, being the highest recorded for WPU and stretchable ionic conductor based TENG. This work introduces a novel approach for boosting the output charge density while avoiding the adverse effect of ionic salts in solid conductors through a universal surfactant self-assembly strategy, which can be extended to other materials. Further, the device is used to monitor and harvest the kinetic energy of human body motion.

2.
Adv Mater ; 36(6): e2305415, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37607471

RESUMO

Vanadium redox flow battery (VRFB) promises a route to low-cost and grid-scale electricity storage using renewable energy resources. However, the interplay of mass transport and activation processes of high-loading catalysts makes it challenging to drive high-performance density VRFB. Herein, a surface-to-pore interface design that unlocks the potential of atomic-Bi-exposed catalytic surface via decoupling activation and transport is reported. The functional interface accommodates electron-regulated atomic-Bi catalyst in an asymmetric Bi─O─Mn structure that expedites the V3+ /V2+ conversion, and a mesoporous Mn3 O4 sub-scaffold for rapid shuttling of redox-active species, whereby the site accessibility is maximized, contrary to conventional transport-limited catalysts. By in situ grafting this interface onto micron-porous carbon felt (Bi1 -sMn3 O4 -CF), a high-performance flow battery is achieved, yielding a record high energy efficiency of 76.72% even at a high current density of 400 mA cm-2 and a peak power density of 1.503 W cm-2 , outdoing the battery with sMn3 O4 -CF (62.60%, 0.978 W cm-2 ) without Bi catalyst. Moreover, this battery renders extraordinary durability of over 1500 cycles, bespeaking a crucial breakthrough toward sustainable redox flow batteries (RFBs).

3.
Front Public Health ; 11: 1126126, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361170

RESUMO

Objective: In the present systematic review and meta-analysis, we aimed to evaluate and update the effects of aquatic exercise on physical fitness and quality of life (QoL) in postmenopausal women. Methods: The databases Cochrane Library, PubMed, Web of Science, and MEDLINE were searched for randomized controlled trials (RCTs) on the topic from inception to July 2022. The GetData software was used to extract data from the published images. RevMan5.4 software was used for statistical analysis. Data are expressed as standardized mean difference (SMD) with 95% confidence intervals (CI). I2 index was employed for heterogeneity. Egger's test was used to assess publication bias. We evaluated the methodological quality of included studies using the Physiotherapy Evidence Database scale. Results: We included 594 participants in 16 RCTs (19 comparison groups). The results indicated that aquatic exercise can significantly improve lower limb strength (LLS), upper limb strength (ULS), agility, flexibility, and overall QoL. No significant effects were found on aerobic capacity. Subgroup-analysis results indicated that aquatic exercise only significantly improved LLS, ULS, agility, and flexibility in postmenopausal women < 65 years of age. However, aquatic exercise improves the overall QoL both in postmenopausal women < 65 years and ≥ 65 years. Aquatic resistance exercise significantly improves LLS, ULS, agility and flexibility. In addition, aquatic aerobic exercise can effectively increase LLS, and combined aquatic aerobic and resistance exercise can enhance the overall QoL. Conclusions: Aquatic exercise can effectively improve physical fitness and overall QoL in postmenopausal women, but has limited effects on aerobic capacity; thus, it is highly recommended in postmenopausal women.


Assuntos
Exercício Físico , Pós-Menopausa , Feminino , Humanos , Terapia por Exercício/métodos , Aptidão Física , Qualidade de Vida
4.
Small ; 19(38): e2303415, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37222111

RESUMO

Stretchable power devices and self-powered sensors have become increasingly desired for wearable electronics and artificial intelligence. In this study, an all-solid-state triboelectric nanogenerator (TENG) is reported, whose one solid-state structure prevents delamination during stretch and release cycles and increasing the patch adhesive force (3.5 N) and strain (586% elongation at break). Through the synergetic virtues of stretchability, ionic conductivity, and excellent adhesion to the tribo-layer, reproducible open-circuit voltage (VOC ) of 84 V, charge (QSC ) of 27.5 nC, and short-circuit current (ISC ) of 3.1 µA after drying at 60°C or 20,000 contact-separation cycles are obtained. Apart from contact-separation, this device shows unprecedented electricity generation through stretch-release of solid materials leading to a linear relationship between VOC and strain. For the first time, this work provides a clear explanation of the working mechanism of contact-free stretching-releasing and investigates the relationships of exerted force, strain, thickness of the device, and electric output. Benefitting from the one solid-state structure, this contact-free device remains stable even after repeated stretch-release cycling, maintaining 100% of its VOC after 2500 stretch-release cycles. These findings provide a strategy toward highly conductive and stretchable electrodes for harvesting mechanical energy and health monitoring.

5.
PLoS One ; 17(10): e0275616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36223405

RESUMO

Despite the growing body of literature on the influence of industrial agglomeration on urban innovation, no consensus has been reached on the mechanism of the spillover effect. This empirical study exploits heterogeneity in spillover effects between manufacturing and producer service agglomerations on urban innovation based on a sample of 262 prefecture-level cities in China. We find some intriguing and new findings: (1) The threshold effect can be identified for the spillover effect of manufacturing agglomeration but not for that of producer service agglomeration. (2) Manufacturing and producer service agglomerations have opposite decomposition indirect effect. (3) The spatial spillover effect of industrial agglomeration can be restrained by absorptive capacity of nearby cities. This study not only provides empirical evidence for the reconciliation of the debate on the effect of manufacturing and producer service agglomeration, but also has important policy implication for reconsidering the role of industrial agglomeration in urban innovation.


Assuntos
Comércio , Indústrias , China , Cidades , Desenvolvimento Econômico
6.
PLoS One ; 16(11): e0260214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34843547

RESUMO

With increased uncertainty and instability worldwide, how to enhance the urban economy resilience effectively has become one main issue for urban economic development. Based on the measurement of the economic resilience of 241 cities at the prefecture level and above in China using the sensitive index method, we scrutinize the impact of industrial specialization agglomeration and diversification agglomeration on urban economic resilience. Results indicate that, during the impact resistance period, industrial diversification agglomeration, especially related industrial diversification agglomeration, can enhance urban economic resilience, whereas industrial specialization agglomeration has no positive effect. In contrast, during the period of recovery and adjustment, industrial specialization agglomeration can improve urban economic resilience, and industrial diversification agglomeration, especially related industrial diversification agglomeration, has no positive effect. Further analysis indicates that, under the interaction of specialization and diversification agglomerations, the effect of industrial agglomeration on urban economic resilience depends on the type of dual industrial agglomeration, showing remarkable heterogeneity. This study may provide useful references for policy makers concerned with urban resilience.


Assuntos
Reforma Urbana , China , Cidades , Desenvolvimento Econômico , Humanos , Incerteza , Reforma Urbana/economia
7.
Mol Omics ; 17(5): 769-782, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34254634

RESUMO

Copper (Cu) is one of the essential microelements for plants and algae. It can stimulate growth and photosynthesis at low concentration but inhibit them at higher concentration. The knowledge of molecular response mechanisms to copper stress in green algae is still limited. The responses of the green algae Dunaliella salina to Cu stress were studied using the physiochemical indexes and RNA-seq analysis. The physiochemical indexes such as growth rate, the content of chlorophyll and soluble sugar, photosynthesis and peroxidase activity were all changed in D. salina under Cu stress. In addition, a total of 3799 differentially expressed genes (DEGs) were identified between the control and Cu-treated group. Among these, 2350 unigenes were up-regulated whereas 1449 were down-regulated. Here, the DEGs encoding proteins relevant to photosynthesis, carbon assimilation and carbohydrate mechanism were significantly up-regulated in the Cu-treated group. In addition, the unigenes encoding proteins involved in the antioxidant system and heat shock proteins were also up-regulated, and these were consistent with the expression patterns based on TPM (transcripts per million) values. This study shows that the enhanced growth and photosynthesis and carbon mechanism in D. salina can be triggered by copper, which will lay a firm foundation for future breeding and carotenoid production, further highlighting the underlying application of D. salina as a functional food.


Assuntos
Clorófitas , Cobre , Carbono , Clorófitas/genética , Cobre/toxicidade , Fotossíntese/genética , Transcriptoma
8.
BMC Bioinformatics ; 20(Suppl 25): 688, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874611

RESUMO

BACKGROUND: The occurrence of cotton pests and diseases has always been an important factor affecting the total cotton production. Cotton has a great dependence on environmental factors during its growth, especially climate change. In recent years, machine learning and especially deep learning methods have been widely used in many fields and have achieved good results. METHODS: First, this papaer used the common Aprioro algorithm to find the association rules between weather factors and the occurrence of cotton pests. Then, in this paper, the problem of predicting the occurrence of pests and diseases is formulated as time series prediction, and an LSTM-based method was developed to solve the problem. RESULTS: The association analysis reveals that moderate temperature, humid air, low wind spreed and rain fall in autumn and winter are more likely to occur cotton pests and diseases. The discovery was then used to predict the occurrence of pests and diseases. Experimental results showed that LSTM performs well on the prediction of occurrence of pests and diseases in cotton fields, and yields the Area Under the Curve (AUC) of 0.97. CONCLUSION: Suitable temperature, humidity, low rainfall, low wind speed, suitable sunshine time and low evaporation are more likely to cause cotton pests and diseases. Based on these associations as well as historical weather and pest records, LSTM network is a good predictor for future pest and disease occurrences. Moreover, compared to the traditional machine learning models (i.e., SVM and Random Forest), the LSTM network performs the best.


Assuntos
Clima , Gossypium/parasitologia , Redes Neurais de Computação , Doenças das Plantas/parasitologia , Área Sob a Curva , Gossypium/crescimento & desenvolvimento , Umidade , Curva ROC , Estações do Ano , Temperatura
9.
Cancer Biother Radiopharm ; 34(7): 480-485, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31135180

RESUMO

Objective: PI3K/AKT signal pathway is important for negative regulation of FoxO3a/p27Kip1, maintaining cell survival and inhibiting apoptosis. Phosphatase and tensin homology deleted on chromosome 10 (PTEN) gene negatively regulates PI3K/AKT signal pathway. It's downregulation is correlated with prostate cancer (PC) pathogenesis. Previous study showed significantly elevated miR-26a expression in PC tissues, indicating its tumor facilitating role in PC. Bioinformatics analysis revealed targeted relationship between miR-26a and 3'-UTR of PTEN mRNA. This study investigated if miR-26a and PTEN dysregulation played a role in proliferation and apoptosis of PC-3 cells. Materials and Methods: PC tumor tissues were collected along with benign prostate hyperplasia samples. Expression of miR-26a and PTEN was detected. The targeted relationship between miR-26a and PTEN was analyzed by dual-luciferase reporter gene assay. In vitro-cultured PC-3 cells were treated with miR-26a inhibitor and/or pIRES2-PTEN. Flow cytometry was employed to detect cell apoptosis, cycle, and Ki-67 expression. Expression of miR-26a and PTEN was analyzed. Western blot was employed to detect protein levels of p-AKT, p-FoxO3a, and p27Kip1. Results: PC tissues had elevated miR-26a expression and lower PTEN expression compared with benign hyperplasia. miR-26a targeted and inhibited PTEN expression. Transfection of miR-26a inhibitor and/or overexpression of PTEN significantly decreased phosphorylation activity of AKT and FoxO3a, enhanced p27Kip1 expression, cell apoptosis, weakened proliferation ability, and arrested cell cycle at G0/G1 phase. Conclusions: PC tissue had higher miR-26a and lower PTEN expressions. miR-26a targeted and inhibited PTEN, potentiated phosphorylation activity of AKT and FoxO3a, downregulated p27Kip1 expression, decreased cell apoptosis, and facilitated proliferation.


Assuntos
MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Apoptose , Proliferação de Células , Humanos , Masculino , Neoplasias da Próstata/patologia , Transdução de Sinais , Transfecção
10.
Sci Rep ; 9(1): 7024, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31065055

RESUMO

Insect pests are known to be a major cause of damage to agricultural crops. This paper proposed a deep learning-based pipeline for localization and counting of agricultural pests in images by self-learning saliency feature maps. Our method integrates a convolutional neural network (CNN) of ZF (Zeiler and Fergus model) and a region proposal network (RPN) with Non-Maximum Suppression (NMS) to remove overlapping detections. First, the convolutional layers in ZF Net, without average pooling layer and fc layers, were used to compute feature maps of images, which can better retain the original pixel information through smaller convolution kernels. Then, several critical parameters of the method were optimized, including the output size, score threshold, NMS threshold, and so on. To demonstrate the practical applications of our method, different feature extraction networks were explored, including AlexNet, ResNet and ZF Net. Finally, the model trained on smaller multi-scale images was tested on original large images. Experimental results showed that our method achieved a precision of 0.93 with a miss rate of 0.10. Moreover, our model achieved a mean Accuracy Precision (mAP) of 0.885.


Assuntos
Produtos Agrícolas/parasitologia , Processamento de Imagem Assistida por Computador/métodos , Insetos/crescimento & desenvolvimento , Algoritmos , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Aprendizado Profundo , Modelos Biológicos
11.
J Chromatogr A ; 1330: 6-13, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24461641

RESUMO

Dummy template molecularly imprinted polymers (DMIPs) on silica gel particles for simultaneously selective recognition of nine phthalate esters have been prepared. A novel dummy template molecule with similar structural skeleton to the phthalate ester, diethyl N,N'-phthaloyl-bis(11-aminoundecanoate), has been designed and synthesized. The DMIP films were grafted on the surface of silica gel particles by a sol-gel process with 3-aminopropyltriethoxysilane (APTES) and tetramethoxysilane (TEOS) as functional monomer and cross-linker, respectively, and the obtained sorbents have been characterized by FTIR with diffuse reflectance accessory. The maximum static adsorption capacities of the DMIPs and NIP sorbents for the nine phthalate esters were 281 and 132mg/g respectively, and the results of dynamic adsorption showed that the adsorption equilibrium could be achieved about 5min for the DMIPs sorbents. The imprint factors of the sorbents ranged from 1.8 to 3.0 for eight of the phthalate esters except for Diamyl phthalate, which indicated that the DMIPs sorbents have high selectivity. The competitive experiments of the nine phthalates with some of their analogues on the sorbents illustrated that the DMIPs sorbents have high specificity for the phthalates. A GC-MS method for determination of the phthalate residues in fruit juice have been developed with the DMIPs as sorbents for the solid phase extraction (SPE) in the sample pretreatment procedures. The spiking recoveries of the phthalates were in the range of 72-100.2% with relative standard deviations lower than 10.2%. The results indicated that the obtained sorbents could specifically recognize the phthalates from complex matrices, which provide a new train of thought for preparing the DMIPs sorbents.


Assuntos
Aminoácidos/síntese química , Impressão Molecular , Ácidos Ftálicos/análise , Ácidos Ftálicos/síntese química , Siloxanas/síntese química , Adsorção , Aminoácidos/química , Bebidas/análise , Citrus sinensis , Reagentes de Ligações Cruzadas/química , Ésteres , Frutas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Ftálicos/química , Silanos/química , Sílica Gel , Siloxanas/química , Extração em Fase Sólida/métodos
12.
Zhonghua Zhong Liu Za Zhi ; 33(4): 299-301, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21575504

RESUMO

OBJECTIVE: To observe the local control rate, survival time and side effect of three-dimensional conformal radiation therapy combined with Tegafur for postoperative recurrent rectal carcinoma. METHODS: Forty patients with postoperative recurrent rectal carcinoma received three-dimensional conformal radiation therapy, 1.8 - 2.0 Gy/once, 5 times every week and the total dose was 54 - 65 Gy. At the same time, the patients took Tegafur orally 40 mg/m(2) twice per day for consecutive 28 days, and one cycle lasted for 42 days. The chemotherapy was applied for 2 cycles after radiotherapy. RESULTS: The total effective rate (CR + PR) was 70.0%, improvement rate was 90.0%, 1-year survival rate was 70.0%, and 1-year local control rate was 62.5%. There was only a little side effect. CONCLUSIONS: Three-dimensional conformal radiation therapy combined with Tegafur for postoperative recurrent rectal carcinoma have definite effect, with a high local control rate, and patients well tolerance the treatment without serious side effect. It can apparently improve the life quality of the patients.


Assuntos
Adenocarcinoma , Antimetabólitos Antineoplásicos/uso terapêutico , Recidiva Local de Neoplasia , Radioterapia Conformacional , Neoplasias Retais , Tegafur/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Terapia Combinada , Diarreia/etiologia , Exantema/induzido quimicamente , Exantema/etiologia , Feminino , Humanos , Leucopenia/etiologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Período Pós-Operatório , Qualidade de Vida , Radioterapia Conformacional/efeitos adversos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Indução de Remissão , Taxa de Sobrevida , Tegafur/efeitos adversos
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