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1.
ACS Sens ; 9(6): 3057-3065, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38808653

RESUMO

High-sensitivity sensors in practical applications face the issue of environmental noise interference, requiring additional noise reduction circuits or filtering algorithms to improve the signal-to-noise ratio (SNR). To address this issue, this study proposes a biomimetic crack pressure sensor with selective frequency response based on hydrogel dampers. The core of this research is to construct a biomimetic crack pressure sensor with selective frequency response using the high-pass filtering characteristics of gelatin-chitosan hydrogels. This design, inspired by the slit sensilla and stratum corneum structure of spider legs, delves into the material properties and principles of hydrogel dampers, exploring their application in biomimetic crack pressure sensors, including parameter selection, structural design, and performance optimization. By delving into the nuanced characteristics and working principles of hydrogel dampers, their integration in biomimetic crack pressure sensors is examined, focusing on aspects like parameter selection, structural engineering, and performance enhancement to selectively sieve out low-frequency noise and transmit target vibrational signals. Experimental results demonstrate that this innovative sensor, while suppressing low-frequency vibration signals, can selectively detect high-frequency signals with high sensitivity. At different vibration frequencies, the relative change in resistance exceeds 200%, and the sensor sensitivity is 7 × 104 kPa-1. Furthermore, this sensor was applied to human voice detection, and the corresponding results verified its frequency-selective performance evidently. This study not only proposes a new design for pressure sensors but also offers fresh insights into the application of biomimetic crack pressure sensors in intricate environments.


Assuntos
Hidrogéis , Pressão , Hidrogéis/química , Biomimética , Materiais Biomiméticos/química , Quitosana/química , Gelatina/química , Razão Sinal-Ruído , Vibração
2.
Molecules ; 28(18)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37764409

RESUMO

Three mononuclear compounds formulated as {M[(2-1H-tetrazol-5-yl)pyridine]2(H2O)2} (M = FeII (1), CoII (2), CuII (3)) were reported and synthesized. Their space group is monoclinic, P21/c, revealed by single-crystal X-ray diffraction. Antiferromagnetic interactions exist in Compounds 1, 2 and 3, as evidenced by magnetic and low-temperature heat capacity measurements. In addition, their thermodynamic functions were determined by a relaxation calorimeter, indicating that Compound 1 exhibits a Schottky anomaly in low-temperature heat capacity. This work can provide an important fundamental basis for the research of the thermophysical properties of molecular-based magnetic materials.

3.
Int J Rheum Dis ; 19(11): 1132-1142, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26354025

RESUMO

AIM: To evaluate the efficacy of etanercept (ETA) for treating active rheumatoid arthritis (RA) compared to placebo or methotrexate (MTX). METHODS: We searched Medline, Cochrane Library and Wiley databases. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated to compare efficacy. RESULTS: In total, 12 studies with 3878 active RA patients (including 2046 patients treated with ETA and 1832 patients treated with placebo or MTX) were included. The overall RRs in ACR20, 50 and 70 (20%, 50%, 70% improvement based on the criteria of American Rheumatism Association) were 2.10 (95% CI: 1.45-3.02, P < 0.0001), 2.87 (95% CI: 1.66-4.97, P = 0.0002) and 2.16 (95% CI: 1.49-3.13, P < 0.0001) within 24 weeks, respectively and were 1.19 (95% CI: 1.11-1.28, P < 0.00001), 1.37 (95% CI: 1.22-1.53, P < 0.00001) and 1.57 (95% CI: 1.28-1.92, P < 0.00001) within 1-3 years, respectively. Further, the overall RRs of 25 mg versus 10 mg ETA twice weekly in ACR20, 50 and 70 were 1.10 (95% CI: 1.02-1.19, P < 0.02), 1.37 (95% CI: 0.98-1.92, P < 0.07) and 1.27 (95% CI: 1.02-1.58, P < 0.03), respectively. CONCLUSIONS: In active RA patients treated with ETA, there was significantly higher efficacy compared to the treatment of placebo or MTX. High doses of ETA were more effective for active RA patients.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Etanercepte/uso terapêutico , Antirreumáticos/efeitos adversos , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/imunologia , Distribuição de Qui-Quadrado , Etanercepte/efeitos adversos , Humanos , Metotrexato/uso terapêutico , Razão de Chances , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
4.
Reprod Sci ; 22(9): 1098-106, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25759370

RESUMO

Although our previous study confirmed that periostin (PN) was overexpressed in the eutopic and ectopic endometrial stroma of women with endometriosis by immunohistochemitry, the role of PN in the pathophysiology of endometriosis remains unknown. Thus, we aimed to investigate the effects of PN on endometrial stromal cells (ESCs) migration, invasion, adhesion, and proliferation and to further study the mechanism under this process. Eutopic (EuSCs), ectopic (EcSCs), and normal ESCs (NSCs) were isolated and cultured. We evaluated the above-mentioned biology behaviors and the expression of PN, integrin-linked kinase 1 (ILK1), and phospho-Akt (p-Akt) in NSCs, EuSCs as well as EcSCs before and after receiving PN small-interfering RNA (siRNA). The protein and messenger RNA (mRNA) levels of PN were upregulated in EuSCs (P < .05; P = .2261 in proliferative phase and P = .3385 in secretory phase) and EcSCs (P < .001; P < .001 in proliferative phase and P < .05 in secretory phase) compared with NSCs, although there was no significant difference in PN mRNA between EuSCs and NSCs. In EcSCs, abilities of migration, invasion, and adhesion and the expressions of ILK1 and p-Akt were enhanced; and all of those were downregulated after PN siRNA interference. Thus, PN enhanced ESCs migration, invasion, and adhesion due to the ILK1/Akt signal pathway. As an agonist in the development and progression of endometriosis, PN may be a new clinical treatment target of endometriosis.


Assuntos
Moléculas de Adesão Celular/metabolismo , Adesão Celular , Movimento Celular , Endometriose/enzimologia , Endométrio/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Células Estromais/enzimologia , Adulto , Moléculas de Adesão Celular/genética , Proliferação de Células , Células Cultivadas , Endometriose/genética , Endometriose/patologia , Endométrio/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Interferência de RNA , Células Estromais/patologia , Fatores de Tempo , Transfecção
5.
Plant Physiol Biochem ; 70: 69-80, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23770596

RESUMO

This study investigated changes in leaf abscisic acid (ABA) concentrations and grain ABA concentrations in two maize cultivars and analyzed the following relationships under different water/nitrogen treatments: leaf ABA concentrations and photosynthetic parameters; leaf ABA concentrations and grain ABA concentrations; leaf/grain ABA concentrations and grain-filling parameters; and aldehyde oxidase (AO, EC 1.2.3.1) activities and ABA concentrations. The ear leaf average AO activities and ABA concentrations were lower in the controlled release urea treatments compared with the conventional urea treatments. The average AO activities in the grains were higher in the controlled release urea treatments, and the ABA concentrations were significantly increased at 11-30 DAF. The Pn and ABA concentrations in ear leaves were negatively correlated. And the Gmean were positively correlated with the grain ABA concentrations at 11-30 DAF and negatively correlated with the leaf ABA concentrations at 20 and 40-50 DAF. The grain ABA concentrations and leaf ABA concentrations were positively correlated. Thus, the Gmean were closely related to the AO activities and to the ear leaf and grain ABA concentrations. As compared to other treatments, the subsoiling and controlled release urea treatment promoted the uptake of water and nitrogen by maize, increased the photosynthetic capacity of the ear leaves, increased the grain-filling rate, and improved the movement of photosynthetic assimilates toward the developing grains. In the cultivar Z958, higher ABA concentrations in grains at 11-30 DAF and lower ABA concentrations in ear leaves during the late grain-filling stage, resulted in higher grain-filling rate and increased accumulation of photosynthetic products (relative to the cultivar D3).


Assuntos
Ácido Abscísico/metabolismo , Aldeído Oxidase/metabolismo , Nitrogênio , Fotossíntese , Estruturas Vegetais/metabolismo , Água , Zea mays/metabolismo , Adaptação Fisiológica , Fertilizantes , Flores , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Sementes/metabolismo , Especificidade da Espécie , Ureia/metabolismo , Zea mays/fisiologia
6.
Huan Jing Ke Xue ; 32(4): 936-42, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21717729

RESUMO

The odor pollution of landfill is one of seriously pollutions in city ambient area. Main pollution points in the landfill area have been detected by preliminary research. For a particular purpose to recover the materials changing in odor dispersion process and to find out odor indication material, GC-MS method was used to detect materials in the different site at down wind direction. Then, similarity coefficient of VOCs (volatile organic compounds) composition between every two site were calculated and compared to look for changing regular of odor pollution in diffusion process. The odor pollution indictor material has be found in the materials that appeared in down wind direction of operation area and compared its' olfaction threshold. The results show that: there have 19 types of common materials in the landfill area, including monoaromatics, alkanes and halogenated compounds; Materials in the air of operation area site has marked influence on down windward direction air of landfill, and m-xlyene has been selected as odor pollution indictor of landfill air by this research.


Assuntos
Poluentes Atmosféricos/análise , Odorantes/análise , Eliminação de Resíduos , Compostos Orgânicos Voláteis/análise , China , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas
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