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1.
Langmuir ; 40(3): 1774-1784, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38194298

RESUMEN

The current study presents a scalable approach for the preparation of temperature-responsive PEG/SiO2/PNIPAM-PEA Janus particles and, for the first time, investigates their potential applications in stabilizing foam and defoaming by adjusting the temperature. The method utilizes a (W1 + O)/W2 emulsion system, which incorporates appropriate surfactants to stabilize the emulsion and prevent rapid dissolution of the hydrophilic triblock polymer PEG-b-PTEPM-b-PNIPAM in water. The PEG/SiO2/PNIPAM-PEA Janus particles with temperature-responsive characteristics were synthesized in a single step that combined the sol-gel reaction and photoinduced free radical polymerization. The contact angle of the hydrophilic PEG/SiO2/PNIPAM surface was measured to be 54.7 ± 0.1°, while the contact angle of the hydrophobic PEA surface was found to be 122.4 ± 0.1°. By incorporating PEG/SiO2/PNIPAM-PEA Janus particles at a temperature of 25 °C, the foam's half-life is significantly prolonged from 42 s to nearly 30 min. However, with an increase in temperature to 50 °C, the foam's half-life rapidly diminished to only 44 s. This innovative application effectively enhances foam stabilization at low temperatures and facilitates the rapid dissipation of foam at high temperatures.

2.
Langmuir ; 40(17): 8981-8991, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38627903

RESUMEN

In this study, we proposed a method for fabricating Janus sheets using biological "microflowers" as a sacrificial template. The microflower-templated Janus sheets (MF-JNSs) were employed as a foam stabilizer in foam separation of the whey soybean protein (WSP). The MF-JNSs took inorganic hybrid microflowers (BSA@Cu3 (PO4)2-MF) as template, followed by the sequential attachment of protamine and silica to the surface of the BSA@Cu3(PO4)2-MF. Subsequently, the template was removed using ethylenediaminetetraacetic acid after the silicon dioxide was modified by 3-(methacryloyloxy) propyl trimethoxysilane. Upon template dissolution, the modified silica layer, lacking support from the core, fractured to form the MF-JNSs. This method omitted the step of treating the hollow ball by external force and obtained Janus sheets in one step, indicating that it was simple and feasible. The morphology, structure, and composition of the MF-JNSs were analyzed by SEM, TEM, AFM, XRD, and FT-IR. The MF-JNSs were found to delay the breakage time of the Pickering emulsion, demonstrating their emulsion stabilizing capability. Importantly, they significantly enhanced the foam half-life and foam height of soybean whey wastewater (SWW). Moreover, the recovery percentage and enrichment ratio of WSP, separated from SWW by foam separation, were improved to 81 ± 0.28 and 1.20 ± 0.05%, respectively.

3.
Protein Expr Purif ; 222: 106535, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38901714

RESUMEN

Human superoxide dismutase (hSOD1) plays an important role in the aerobic metabolism and free radical eliminating process in the body. However, the production of existing SOD faces problems such as complex purification methods, high costs, and poor product stability. This experiment achieved low-cost, rapid, and simple purification of hSOD1 through ammonium sulfate precipitation method and heat resistance of recombinant protein. We constructed a recombinant protein hSOD1-LR containing a resilin-like polypeptide tag and expressed it. The interest protein was purified by ammonium sulfate precipitation method, and the results showed that the purification effect of 1.5 M (NH4)2SO4 was the best, with an enzyme activity recovery rate of 80 % after purification. Then, based on its thermal stability, further purification of the interest protein at 60 °C revealed a purification fold of up to 24 folds, and the purification effect was similar to that of hSOD1-6xHis purified by nickel column affinity chromatography. The stability of hSOD1-LR showed that the recombinant protein hSOD1-LR has better stability than hSOD-6xHis. hSOD1-LR can maintain 76.57 % activity even after 150 min of reaction at 70 °C. At same time, hSOD1-LR had activity close to 80 % at pH < 5, indicating good acid resistance. In addition, after 28 days of storage at 4 °C and 40 °C, hSOD1-LR retained 92 % and 87 % activity, respectively. Therefore, the method of purifying hSOD1-LR through salt precipitation may have positive implications for the study of SOD purification.

4.
Sensors (Basel) ; 23(9)2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37177632

RESUMEN

Stochastic resonance (SR), as a type of noise-assisted signal processing method, has been widely applied in weak signal detection and mechanical weak fault diagnosis. In order to further improve the weak signal detection performance of SR-based approaches and realize high-performance weak fault diagnosis, a global parameter optimization (GPO) model of a cascaded SR system is proposed in this work. The cascaded SR systems, which involve multiple multi-parameter-adjusting SR systems with both bistable and tri-stable potential functions, are first introduced. The fixed-parameter optimization (FPO) model and the GPO models of the cascaded systems to achieve optimal SR outputs are proposed based on the particle swarm optimization (PSO) algorithm. Simulated results show that the GPO model is capable of achieving a better SR output compared to the FPO model with rather good robustness and stability in detecting low signal-to-noise ratio (SNR) weak signals, and the tri-stable cascaded SR system has a better weak signal detection performance compared to the bistable cascaded SR system. Furthermore, the weak fault diagnosis approach based on the GPO model of the tri-stable cascaded system is proposed, and two rolling bearing weak fault diagnosis experiments are performed, thus verifying the effectiveness of the proposed approach in high-performance adaptive weak fault diagnosis.

5.
Sensors (Basel) ; 22(22)2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36433327

RESUMEN

As a powerful feature extraction tool, a convolutional neural network (CNN) has strong adaptability for big data applications such as bearing fault diagnosis, whereas the classification performance is limited when the quality of raw signals is poor. In this paper, stochastic resonance (SR), which provides an advanced feature enhancement approach for weak signals with strong background noise, is introduced as a data pre-processing method for the CNN to improve its classification performance. First, a multiparameter adjusting bistable Duffing system that can achieve SR under large-parameter weak signals is introduced. A hybrid optimization algorithm (HOA) combining the genetic algorithm (GA) and the simulated annealing (SA) is proposed to adaptively obtain the optimized parameters and output signal-to-noise ratio (SNR) of the Duffing system. Therefore, the data optimization based on the multiparameter-adjusting SR of Duffing system can be realized. An SR-based mapping method is further proposed to convert the outputs of the Duffing system into grey images, which can be further processed by a normal CNN with batch normalization (BN) layers and dropout layers. After verifying the feasibility of the HOA in multiparameter optimization of the Duffing system, the bearing fault data set from the CWRU bearing data center was processed by the proposed fault enhancement classification and identification method. The research showed that the weak features of the bearing signals could be enhanced significantly through the adaptive multiparameter optimization of SR, and classification accuracies for 10 categories of bearing signals could achieve 100% and those for 20 categories could achieve more than 96.9%, which is better than other methods. The influences of the population number on the classification accuracies and calculation time were further studied, and the feature map and network visualization are presented. It was demonstrated that the proposed method can realize high-performance fault enhancement classification and identification.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Vibración
6.
Fish Shellfish Immunol ; 50: 142-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26826424

RESUMEN

The macrophage migration inhibitory factor (MIF) family, consisting of MIF and D-dopachrome tautomerase (DDT) in vertebrates, is evolutionarily ancient and has been found across Kingdoms including vertebrates, invertebrates, plants and bacteria. The mammalian MIF family are chemokines at the top of the inflammatory cascade in combating infections. They also possess enzymatic activities, e.g. DDT catalysis results in the production of 5,6-dihydroxyindole (DHI), a precursor of eumelanin. MIF-like genes are widely distributed, but DDT-like genes have only been described in vertebrates and a nematode. In this report, we cloned a DDT-like gene, for the first time in arthropods, and a second MIF in mud crab. The mud crab MIF family have a three exon/two intron structure as seen in vertebrates. The identification of a DDT-like gene in mud crab and other arthropods suggests that the separation of MIF and DDT preceded the divergence of protostomes and deuterostomes. The MIF family is differentially expressed in tissues of adults and during embryonic development and early life. The high level expression of the MIF family in immune tissues, such as intestine and hepatopancreas, suggests an important role in mud crab innate immunity. Mud crab DDT is highly expressed in early embryos, in megalops and crablets and this coincides with the requirement for melanisation in egg chorion tanning and cuticular hardening in arthropods, suggesting a potential novel role of DDT in melanogenesis via its tautomerase activity to produce DHI in mud crab. The clarification of the presence of both MIF and DDT in this report paves the way for further investigation of their functional roles in immunity and in melanogenesis in mud crab and other arthropods.


Asunto(s)
Proteínas de Artrópodos/genética , Braquiuros/genética , Braquiuros/inmunología , Oxidorreductasas Intramoleculares/genética , Factores Inhibidores de la Migración de Macrófagos/genética , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Braquiuros/metabolismo , Clonación Molecular , ADN Complementario/genética , ADN Complementario/metabolismo , Oxidorreductasas Intramoleculares/química , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/química , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Especificidad de Órganos , Filogenia , ARN/genética , ARN/metabolismo , Alineación de Secuencia
7.
Biol Trace Elem Res ; 200(3): 1078-1088, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34263420

RESUMEN

Exposure to heavy metals in the environment exerts serious effects on kidney health. However, the effects of joint exposure on the kidneys have been rarely studied, particularly in non-occupational exposure high-risk populations. This study provided a reference threshold range of heavy metals in urine and explored the effect of joint exposure on nephrolithiasis in men. The data were obtained from the China Multi-Ethnic Cohort database, and 1502 men were included in the study. A two-piece-wise regression model was used to assess the dose-response relationship between heavy metal exposure and nephrolithiasis. The least absolute shrinkage and selection operator regression model was used to calculate the score of joint exposure to heavy metals. The threshold effect analysis revealed a linear relationship between the concentration of arsenic (As) in the urine and the prevalence of nephrolithiasis, whereas a nonlinear relationship was observed with cadmium (Cd), chromium (Cr), mercury (Hg), and lead (Pb). In addition, As, Cd, Cr, Hg, and Pb may significantly affect the joint exposure effect. Moreover, the final risk of nephrolithiasis increased by 123% (P for trend < 0.001). This study found a threshold relationship between heavy metals (Cd, Cr, Hg, Pb) in male urine and the occurrence of nephrolithiasis. Joint exposure to heavy metals in urine caused a high-risk effect on nephrolithiasis. The study provided a reference threshold value of related studies and indicated that environmental pollution caused by heavy metals should be reduced.


Asunto(s)
Arsénico , Mercurio , Metales Pesados , Nefrolitiasis , Arsénico/análisis , China/epidemiología , Monitoreo del Ambiente , Humanos , Masculino , Mercurio/toxicidad , Metales Pesados/análisis , Metales Pesados/toxicidad , Nefrolitiasis/inducido químicamente , Nefrolitiasis/epidemiología , Prevalencia , Medición de Riesgo
8.
Acta Cardiol ; 77(2): 136-145, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33683186

RESUMEN

BACKGROUND: Studies examining the association between levels of serum uric acid (SUA) and risk of prehypertension still remained controversial conclusions. Also, a quantitative assessment of the dose-response association between them has not been reported. We aimed to quantitatively evaluate risk of prehypertension with levels of SUA based on observational study. METHODS: We searched the PubMed, Embase, and Web of Science databases up to December 3, 2019 for relevant studies. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effects models. The possible linear or non-linear SUA-prehypertension association was modelled by restricted cubic splines. RESULTS: We included 17 articles (17 studies) with a total of 79,358 participants and 34,591 cases of prehypertension. Compared with lowest levels of SUA, risk of prehypertension increased 46% (RR 1.46, 95% CI 1.28-1.66) for highest levels of SUA. For per 1 mg/dL increment in levels of SUA, risk of prehypertension increased by 12% (RR 1.12, 95% CI 1.08-1.17). Also, we found evidence of a linear SUA-prehypertension association (Pnon-linearity=.368). CONCLUSION: Elevated levels of SUA may be associated with increased risk of prehypertension. Present findings provide the evidence that lowering levels of SUA should be suggested in order to reduce the risk of prehypertension. More longitudinal and intervention studies are needed to clarify the optimal protective levels and whether reducing levels of SUA could prevent or control prehypertension and the progression of prehypertension to hypertension.


Asunto(s)
Hipertensión , Prehipertensión , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Anamnesis , Estudios Observacionales como Asunto , Prehipertensión/diagnóstico , Prehipertensión/epidemiología , Factores de Riesgo , Ácido Úrico
9.
Biol Trace Elem Res ; 200(3): 943-952, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33846928

RESUMEN

It has been previously reported that family history of hypertension (FHH) and exposure to metals are each independent risk factor for hypertension, but the interaction between the two in relation to hypertension risk has been poorly studied. The object of this study is Dong ethnic group in Guizhou, China. The impacts of exposure to metals and FHH on hypertension incidence were examined by using the restrictive cubic spline (RCS) model as well as the multivariate logistic regression model. As a result, FHH, together with cobalt and lead exposure, was identified to show independent significant correlation with hypertension incidence (P < 0.05). The risk of hypertension increased with the increase in lead and cobalt exposure quartiles. Typically, the RCS model revealed such dose-response relation. To further confirm the association of cobalt, lead, and FHH with the risk of hypertension, multiplication and addition models were used to analyze the influence of the interactions between these variables on the risk of hypertension. The results showed that there was a multiplying interaction between the influence of the FHH and cobalt on the risk of hypertension. As for the additive interaction between cobalt and FHH, the relative excess risk due to interaction (RERI) was determined to be 0.596 (95% Cl: 0.001-1.191), the attributable proportion due to interaction (AP) was calculated as 0.256 (95% Cl: 0.075-0.437), whereas the synergy index (S) was identified to be 1.814 (95% Cl: 1.080-3.047). Our study provides some limited evidence that a FHH and cobalt exposure synergistically promote the prevalence of hypertension.


Asunto(s)
Cobalto , Hipertensión , Cobalto/toxicidad , Estudios Transversales , Humanos , Hipertensión/inducido químicamente , Hipertensión/epidemiología , Prevalencia , Factores de Riesgo
10.
Acta Cardiol ; 76(7): 748-753, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32539677

RESUMEN

BACKGROUND: Various magnitudes of the risk of incident hypertension (IHTN) have been reported to be associated with increased serum uric acid (SUA) levels in observational studies, however, whether a dose-response relation exists is unclear. We aimed to quantitatively evaluate the SUA-IHTN association. METHODS: We searched the PubMed and Embase databases for relevant articles published prior to 21 October 2019. Random-effects models were used to estimate the summary relative risks (RRs) and 95% confidence intervals (CIs) of the IHTN risk in relation to SUA levels. We used restricted cubic splines to model the dose-response association between SUA levels and IHTN. RESULTS: A total of 17 articles (17 prospective cohort studies) including 321,716 adults and 65,890 IHTN cases were identified. The pooled RR was 1.10 (95% CI 1.07-1.13; I2=90.7%; n = 17) per 1 mg/dL change in the SUA level. In addition, we found evidence of a linear and positive dose-response association between SUA levels and IHTN (Pnon-linearity = 0.069). The results of the subgroup and sensitivity analyses were consistent with those of the primary analysis. CONCLUSION: These data suggested that people with higher SUA levels had a higher IHTN risk. SUA levels need to be controlled to reduce or eliminate the risk of IHTN associated with SUA levels. Clinical trial studies or diagnostic studies are needed to determine the optimal cut-off point for SUA.


Asunto(s)
Hipertensión , Ácido Úrico , Adulto , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Estudios Prospectivos , Factores de Riesgo
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