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A huge production of waste activated sludge (WAS) has been a burden for wastewater treatment plants (WWTPs) with high disposal cost and little benefit back to wastewater purification. The short-chain fatty acids (SCFAs) produced by a short-term acidogenic fermentation of WAS before methane production have been proven to be a high-quality carbon source available for microbial denitrification process. The dual purpose of full recovery of fermentation liquid products and facilitating disposal of residual solid waste necessitate an efficient solid-liquid separation process of short-term fermentation liquid. The transformation and loss of various soluble carbon sources between solid and liquid are very important issues for carbon recovery efficiency when combining short-term fermentation and sludge dewatering in WWTPs. Here we testified the three conventional preconditioning coagulants, Polyferric Sulfate (PFS), Poly Aluminum Chloride (PAC) and Polyacrylamide (PAM), to improve the efficiency of subsequent solid-liquid separation. The results show that conversion yield of SCFAs in the liquid phase of sludge after short-term fermentation was 195 mg COD/g VSS, when using the coagulants PFS, PAC, and PAM for recovery, the recovery ratio was 79.5%, 82.0%, and 85.9%, respectively, while the dewaterability could be improved after preconditioning short-term fermentation sludge. The complexation of Al3+/Fe3+ in metal coagulants with carboxyl groups of SCFA demonstrated by Density Functional Theory calculation led to small part of soluble carbons co-migration to the solid phase, mainly a loss of high molecular weight organic compounds (carbohydrate, proteins, humic acids), while the application of PAM had little impact on carbon recovery. Economic calculations further showed PAM preconditioning short-term fermentation liquid of WAS could achieve higher recovery benefits.
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Esgotos , Purificação da Água , Fermentação , Carbono , Ácidos Graxos VoláteisRESUMO
BACKGROUND: Previously we reported that inhibition of GPR17 prevents amyloid ß 1-42 (Aß1-42)-induced cognitive impairment in mice. However, the role of GPR17 on cognition is still largely unknown. METHODS: Herein, we used a mouse model of cognitive impairment induced by lipopolysaccharide (LPS) to further investigate the role of GPR17 in cognition and its potential mechanism. The mice were pretreated with GPR17 shRNA lentivirus and cangrelor by microinjection into the dentate gyrus (DG) region of the hippocampus. After 21 days, LPS (0.25 mg/kg, i.p.) was administered for 7 days. Animal behavioral tests as well as pathological and biochemical assays were performed to evaluate the cognitive function in mice. RESULTS: LPS exposure resulted in a significant increase in GPR17 expression at both protein and mRNA levels in the hippocampus. Gene reduction and pharmacological blockade of GPR17 improved cognitive impairment in both the Morris water maze and novel object recognition tests. Knockdown and inhibition of GPR17 inhibited Aß production, decreased the expression of NF-κB p65, increased CREB phosphorylation and elevated BDNF expression, suppressed the accumulation of pro-inflammatory cytokines, inhibited Glial cells (microglia and astrocytes) activation, and increased Bcl-2, PSD-95, and SYN expression, reduced Bax expression as well as decreased caspase-3 activity and TUNEL-positive cells in the hippocampus of LPS-treated mice. Notably, knockdown and inhibition of GPR17 not only provided protective effects against cholinergic dysfunction but also facilitated the regulation of oxidative stress. In addition, cangrelor pretreatment can effectively inhibit the expression of inflammatory cytokines by suppressing NF-κB/CREB/BDNF signaling in BV-2 cells stimulated by LPS. However, activation of hippocampal GPR17 with MDL-29951 induced cognitive impairment in normal mice. CONCLUSIONS: These observations indicate that GPR17 may possess a neuroprotective effect against LPS-induced cognition deficits, and neuroinflammation by modulation of NF-κB/CREB/BDNF signaling in mice, indicating that GPR17 may be a promising new target for the prevention and treatment of AD.
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Disfunção Cognitiva , Lipopolissacarídeos , Camundongos , Animais , Lipopolissacarídeos/efeitos adversos , NF-kappa B/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/prevenção & controle , Disfunção Cognitiva/metabolismo , Citocinas/metabolismo , Microglia/metabolismo , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismoRESUMO
Enzymes are closely associated with the onset and progression of numerous diseases, making enzymes a primary target in innovative drug development. However, the challenge remains in identifying compounds that exhibit potent inhibitory effects on the target enzymes. With the continuous expansion of the total number of natural products and increasing difficulty in isolating and enriching new compounds, traditional high-throughput screening methods are finding it increasingly challenging to meet the demands of new drug development. Virtual screening, characterized by its high efficiency and low cost, has gradually become an indispensable technology in drug development. It represents a prominent example of the integration of artificial intelligence with biopharmaceuticals and is an inevitable trend in the rapid development of innovative drug screening in the future. Therefore, this article primarily focused on systematically reviewing the recent applications of virtual screening technology in the development of enzyme inhibitors and explored the prospects and advantages of using this technology in developing new drugs, aiming to provide essential theoretical insights and references for the application of related technologies in the field of new drug development.
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Inteligência Artificial , Inibidores Enzimáticos , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala , Simulação de Acoplamento MolecularRESUMO
The analysis of the leading active molecular motions in the on-the-fly trajectory surface hopping simulation provides the essential information to understand the geometric evolution in nonadiabatic dynamics. When the ring deformation is involved, the identification of the key active coordinates becomes challenging. A "hierarchical" protocol based on the dimensionality reduction and clustering approaches is proposed for the automatic analysis of the ring deformation in the nonadiabatic molecular dynamics. The representative system keto isocytosine is taken as the prototype to illustrate this protocol. The results indicate that the current hierarchical analysis protocol is a powerful way to clearly clarify both the major and minor active molecular motions of the ring distortion in nonadiabatic dynamics.
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Simulação de Dinâmica Molecular , Análise por Conglomerados , Análise de Componente PrincipalRESUMO
OBJECTIVE: To understand the occurrence of atopic dermatitis (AD) in children aged 2 years on exposure to maternal group B streptococcus (GBS) antibiotic prophylaxis (IAP). DESIGN: Retrospective cohort study of 2909 mother-child pairs. SETTING: Taixing People's Hospital in Eastern China. PARTICIPANTS: Term infants born 2018-2019, followed longitudinally from birth to 2 years. EXPOSURES: The GBS-IAP was defined as therapy with intravenous penicillin G or ampicillin or cefazolin ≥ 4 h prior to delivery to the mother. Reference infants were defined as born without or with other intrapartum antibiotic exposure. OUTCOMES: The logistic regression models were employed to analyze the effect of intrapartum GBS prophylaxis on AD in 2-year-old children during delivery. Analysis was a priori stratified according to the mode of delivery and adjusted for relevant covariates. RESULTS: The cohorts showed that preventive GBS-IAP was potentially associated with increased incidence of AD in children delivered vaginally according to logistic regression models before and after covariate-adjusted treatment (OR: 6.719,95% CI: 4.730-9.544,P < 0.001;aOR: 6.562,95% CI: 4.302-10.008, P < 0.001). CONCLUSION: Prophylactic treatment of intrapartum GBS may raise the risk of AD in vaginally delivered children. These findings highlight the need to better understand the risk between childhood AD and current GBS-IAP intervention strategies.
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Dermatite Atópica , Lactente , Feminino , Humanos , Pré-Escolar , Criança , Estudos de Coortes , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/epidemiologia , Dermatite Atópica/prevenção & controle , Estudos Retrospectivos , Streptococcus agalactiae , MãesRESUMO
According to the whole-genome bioinformatics analysis, a heme-binding protein from Nocardia seriolae (HBP) was found. HBP was predicted to be a bacterial secretory protein, located at mitochondrial membrane in eukaryotic cells and have a similar protein structure with the heme-binding protein of Mycobacterium tuberculosis, Rv0203. In this study, HBP was found to be a secretory protein and co-localized with mitochondria in FHM cells. Quantitative analysis of mitochondrial membrane potential value, caspase-3 activity, and transcription level of apoptosis-related genes suggested that overexpression of HBP protein can induce cell apoptosis. In conclusion, HBP was a secretory protein which may target to mitochondria and involve in cell apoptosis in host cells. This research will promote the function study of HBP and deepen the comprehension of the virulence factors and pathogenic mechanisms of N. seriolae.
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Doenças dos Peixes , Nocardiose , Nocardia , Animais , Apoptose , Proteínas de Bactérias/metabolismo , Doenças dos Peixes/microbiologia , Proteínas Ligantes de Grupo Heme , Nocardia/genética , Nocardia/metabolismo , Nocardiose/microbiologia , Nocardiose/veterináriaRESUMO
OBJECTIVE: To evaluate the efficacy of the second operation within 1 week after ineffective microvascular decompression (MVD) for patients with primary hemifacial spasm (HFS), and to find out the causes of failure. METHODS: The surgery records and postoperative follow-ups of 52 primary HFS patients who had poor relief of spasm after their first MVDs were investigated. Patients were divided into 2 groups. Group A included 46 patients (16 males and 30 females) that went through the second operation within 1 week after the failure of the first MVD. Group B included 6 patients (3 males and 3 females) which did not take the reoperation. The level of spasm of each patient was then re-evaluated 1 year after the first surgery. RESULTS: Among 52 patients who had poor relief after the first MVD between April 2016 and October 2019, 46 patients underwent a second MVD within 1 week while 6 patients refused to take the reoperation. Their mean duration of HFS was 102.4â±â57.9âmonths. During reoperations for patients in group A, we discovered additional sites of neurovascular compression in 11 cases (23.91%). Forty-five patients (97.82%) in group A achieved complete relief 1 year after the second surgery while there was 1 recurrent case. Four patients (66.67%) in group B achieved delayed relief 1 year after the first surgery, while the other 2 patients were still suffering facial spasm in the 1-year follow-up. Group A demonstrated higher relief rate compared to group B in the 1 year follow up (Pâ=â0.032). Although no severe complications occurred on patients in both group, 4 of them suffered grade II facial palsy, and another 3 patients had developed mild temporary hearing loss on the operation side. CONCLUSION: The second operation within 1 week after an ineffective MVD is safe and effective. Full revealing of root exit zone and making sure no neurovascular compression missed with abnormal muscle response monitoring are the keys to a successful MVD.
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Doenças do Nervo Facial , Espasmo Hemifacial , Cirurgia de Descompressão Microvascular , Feminino , Espasmo Hemifacial/cirurgia , Humanos , Masculino , Reoperação , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Spinal cord injury (SCI) routinely causes the immediate loss and disruption of neurons followed by complicated secondary injuries, including inflammation, oxidative stress, and dense glial scar formation. Inhibitory factors in the lesion scar and poor intrinsic neural regeneration capacity restrict functional recovery after injury. Minocycline, which has neuroprotective activity, can alleviate secondary injury, but the long-term administration of this drug may cause toxicity. Polysialic acid (PSA) is a large cell-surface carbohydrate that is critical for central nervous system development and is capable of promoting precursor cell migration, axon path finding, and synaptic remodeling; thus, PSA plays a vital role in tissue repair and regeneration. Here, we developed a PSA-based minocycline-loaded nanodrug delivery system (PSM) for the synergistic therapy of spinal cord injury. The prepared PSM exerted marked anti-inflammatory and neuroprotective activities both in vitro and in vivo. The administration of PSM could significantly protect neurons and myelin sheaths from damage, reduce the formation of glial scar, recruit endogenous neural stem cells to the lesion site, and promote the regeneration of neurons and the extension of long axons throughout the glial scar, thereby largely improving the locomotor function of SCI rats and exerting a superior therapeutic effect. The findings might provide a novel strategy for SCI synergistic therapy and the utilization of PSA in other central nervous system diseases.
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Antibacterianos/uso terapêutico , Portadores de Fármacos/uso terapêutico , Minociclina/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Ácidos Siálicos/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Micelas , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologiaRESUMO
In recent years, with the development of the marine industry, the ship navigation environment has become more complicated. Some artificial intelligence technologies, such as computer vision, can recognize, track and count sailing ships to ensure maritime security and facilitate management for Smart Ocean systems. Aiming at the scaling problem and boundary effect problem of traditional correlation filtering methods, we propose a self-selective correlation filtering method based on box regression (BRCF). The proposed method mainly includes: (1) A self-selective model with a negative samples mining method which effectively reduces the boundary effect in strengthening the classification ability of the classifier at the same time; (2) a bounding box regression method combined with a key points matching method for the scale prediction, leading to a fast and efficient calculation. The experimental results show that the proposed method can effectively deal with the problem of ship size changes and background interference. The success rates and precisions were over 8 % higher than Discriminative Scale Space Tracking (DSST) on the marine traffic dataset of our laboratory. In terms of processing speed, the proposed method is higher than DSST by nearly 22 frames per second (FPS).
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For the treatment of stage III/IV malignant melanoma (MM), a network meta-analysis (NMA) was conducted to compare the short and long-term efficacy of targeted therapy with single or double-drug regimens. All conducted randomized controlled trials (RCTs) searched from PubMed and Cochrane Library were included in the study for direct and indirect comparison for MM. The odds ratio (OR) and surface under the cumulative ranking curves (SUCRA) value of the targeted therapy with single or double-drug regimens for treatment of stage III/IV MM were also analyzed. To group the treatments according to their similarity with regards to both outcomes, cluster analyses were performed. Ultimately, 16 RCTs were incorporated for this NMA. The NMA revealed that the overall response rate (ORR) values of single-drug regimens (Vemurafenib [Vem], Dabrafenib [Dab], and Nivolumab [Niv]) were higher than those of Dacarbazine (Dac). Also the ORR values of double-drug regimens (Dab + Trametinib [Dab + Tra], Niv + Ipilimumab [Niv + Ipi], and Vem + Cobimetinib [Vem + Cob]) were moderately higher than those of Dac. The results of the SUCRA showed that short-term efficacy of single-drug regimens (Vem and Dab) were better, while the short-term efficacy of double-drug regimens (Dab + Tra and Vem + Cob) were relatively better. It was determined that Vem, Dab, and Niv might be the best choice in evaluating the treatment of stage III/IV MM among different single-drug targeted therapy regimens, while Dab + Tra, Niv + Ipi, and Vem + Cob might have better short-term efficacy among different double-drug targeted therapy regimens. J. Cell. Biochem. 119: 640-649, 2018. © 2017 Wiley Periodicals, Inc.
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Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/patologia , Anticorpos Monoclonais/uso terapêutico , Azetidinas/uso terapêutico , Dacarbazina/uso terapêutico , Humanos , Imidazóis/uso terapêutico , Indóis/uso terapêutico , Ipilimumab/uso terapêutico , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Metanálise em Rede , Nivolumabe , Razão de Chances , Oximas/uso terapêutico , Piperidinas/uso terapêutico , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonamidas/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento , VemurafenibRESUMO
BACKGROUND: Vitamins A, D (Vitamin D2 and vitamin D3) and E, play an important role during pregnancy. METHODS: Sera were collected from 1056 normal pregnant women, who were between 18 and 40 years old, at seven different hospitals in northeastern China. The levels of Vitamin A and E in the sera samples were detected using HPLC (High Performance Liquid Chromatography), and the level of vitamin D was measured by LC-MS (Liquid Chromatography-Mass Spectrometry). Data were analyzed using IBM SPSS Statistics 21. RESULTS: The mean levels of vitamin A, D and E in the 1056 sera samples were 0.39 mg/L (0.38-0.39), 20.44 µg/L (19.86-21.08) and 12.96 mg/L (12.70-13.25), respectively. The levels of vitamin A, D, and E deficiency were 17.05%, 0.19%, and 56.44%, respectively. The levels of vitamin A, D, and E of those between age 21 and 31 among the 1056 pregnant women were similar. The correlation of vitamin E and D was significant at the .01 level (two-tailed), and the correlation of vitamin A and age was significant at the .05 level (2-tailed). CONCLUSION: According to our finding, the levels of vitamin A, D, and E in the sera of pregnant women in northeastern China were affected by where they live and their age. Vitamin D deficiency was very serious, vitamin A deficiency was common, while vitamin E seems to be sufficient.
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Gravidez/sangue , Vitamina A/sangue , Vitamina D/sangue , Vitamina E/sangue , Adolescente , Adulto , China/epidemiologia , Feminino , Humanos , Modelos Lineares , Gravidez/estatística & dados numéricos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
Throughout the past decade, vehicular networks have attracted a great deal of interest in various fields. The increasing number of vehicles has led to challenges in traffic regulation. Vehicle-type detection is an important research topic that has found various applications in numerous fields. Its main purpose is to extract the different features of vehicles from videos or pictures captured by traffic surveillance so as to identify the types of vehicles, and then provide reference information for traffic monitoring and control. In this paper, we propose a step-forward vehicle-detection and -classification method using a saliency map and the convolutional neural-network (CNN) technique. Specifically, compressed-sensing (CS) theory is applied to generate the saliency map to label the vehicles in an image, and the CNN scheme is then used to classify them. We applied the concept of the saliency map to search the image for target vehicles: this step is based on the use of the saliency map to minimize redundant areas. CS was used to measure the image of interest and obtain its saliency in the measurement domain. Because the data in the measurement domain are much smaller than those in the pixel domain, saliency maps can be generated at a low computation cost and faster speed. Then, based on the saliency map, we identified the target vehicles and classified them into different types using the CNN. The experimental results show that our method is able to speed up the window-calibrating stages of CNN-based image classification. Moreover, our proposed method has better overall performance in vehicle-type detection compared with other methods. It has very broad prospects for practical applications in vehicular networks.
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Monitoring the status of urban environments, which provides fundamental information for a city, yields crucial insights into various fields of urban research. Recently, with the popularity of smartphones and vehicles equipped with onboard sensors, a people-centric scheme, namely "crowdsensing", for city-scale environment monitoring is emerging. This paper proposes a data correlation based crowdsensing approach for fine-grained urban environment monitoring. To demonstrate urban status, we generate sensing images via crowdsensing network, and then enhance the quality of sensing images via data correlation. Specifically, to achieve a higher quality of sensing images, we not only utilize temporal correlation of mobile sensing nodes but also fuse the sensory data with correlated environment data by introducing a collective tensor decomposition approach. Finally, we conduct a series of numerical simulations and a real dataset based case study. The results validate that our approach outperforms the traditional spatial interpolation-based method.
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The removal of ibuprofen (IBP) in aqueous solution using UV/H2O2 process was evaluated. The response surface methodology (RSM) and Box-Behnken design were employed to investigate the effects of process parameters on IBP removal, including the initial IBP concentration, H2O2 dosage, UV light intensity, and initial pH value of solution. The RSM model developed herein fits well with the experiments, and provides a good insight into the OH radical irritated degradation mechanisms and kinetics. High resolution accurate mass spectrometry coupled with liquid chromatography was used to identify the degradation intermediates. A total of 23 degradation products were identified, including mono-hydroxylated products and dihydroxylated products. A series of OH radical-initiated reactions, including hydroxylation, dihydroxylation, decarboxylation, demethylation, ring break, lead to the final mineralization of IBP to CO2 and H2O. UV/H2O2 technology could be a promising technology for IBP removal in aqueous solution.
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Ibuprofeno/química , Modelos Químicos , Poluentes Químicos da Água/química , Peróxido de Hidrogênio , Ibuprofeno/análise , Cinética , Processos Fotoquímicos , Raios Ultravioleta , Poluentes Químicos da Água/análiseRESUMO
The Compton profiles of methane and ethane molecules have been determined at an incident photon energy of 20 keV based on the third generation synchrotron radiation, and the statistical accuracy of 0.2% is achieved near pz = 0. The density functional theory with aug-cc-pVTZ basis set was used to calculate the Compton profiles of methane and ethane. The present experimental Compton profiles are in better agreement with the theoretical calculations in the whole pz region than the previous experimental results, which indicates that the present experimental Compton profiles are accurate enough to serve as the benchmark data for methane and ethane molecules.
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The amyloid-beta (Aß) aggregation in Alzheimer's disease (AD) triggers neuroinflammation, and neurodegeneration, which lead to cognitive deficits along with other neuropsychiatric symptoms, including depression and anxiety. G protein-coupled receptor 35 (GPR35) is expressed in the brain and is involved in metabolic stresses. However, the role of GPR35 in AD pathogenesis remains unknown. Herein, pharmacological blockade, shRNA-mediated knockdown or knockout of GPR35 was performed to investigate the role and mechanisms of GPR35 in Aß1-42-induced cognitive impairment and emotional alterations in mice. A series of behavioral, histopathological, and biochemical tests were performed in mice. Our results showed that hippocampal GPR35 expression was significantly increased in Aß1-42-induced and APP/PS1 AD mouse models. Pharmacological blockade or knockdown of GPR35 ameliorated cognitive impairment and emotional alterations induced by Aß1-42 in mice. We also found that blockade or knockdown of GPR35 decreased the accumulation of Aß, and improved neuroinflammation, cholinergic system deficiency, and neuronal apoptosis via the RhoA/ROCK2 pathway in Aß1-42-treaed mice. However, activation of GPR35 aggravates Aß1-42-induced cognitive deficits and emotional alterations in mice. In addition, genetic deletion of GPR35 protects against the Aß1-42-induced cognitive deficits and emotional alterations in mice. Moreover, GPR35 could bind to TLR4. These results indicate that GPR35 participates in the pathogenesis of cognitive deficits and emotional alterations induced by Aß1-42 in mice, suggesting that GPR35 could be a potential therapeutic target for AD.
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Walnut protein is a kind of natural, high-quality plant protein resource. However, its high content of gluten, strong hydrophobicity and poor gelation ability have greatly limited its development and utilization in gel products. It was found in this experiment that ultrasonic power combined with transglutaminase (TGase) had a significant effect on the gel properties of the walnut protein isolate (WNPI)-κ-carrageenan (KC) complex. The results showed that the gel strength of the WNPI-KC complex first increased and then decreased with the increase in ultrasonic power (0-400 W). WNPI-KC composite gel had the best texture properties, rheological properties, water-holding capacity (99.41 ± 0.76%), swelling ratio (2.31 ± 0.29%) and thermal stability (83.22 °C) following 200 W ultrasonic pretreatment. At this time, the gel network was more uniform and much denser, and the water molecules were more tightly bound. Further, 200 W ultrasonic pretreatment could promote the transformation of α-helices to ß-folds in protein molecules, improve the fluorescence intensity, increase the content of free sulfhydryl groups and enhance the intermolecular forces. The experimental results could provide technical support for the development of walnut protein gel food.
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Oxybenzone (OXB), a very widely used sunscreen ingredient has the potential to block both UVA and UVB but can penetrate through skin. Studies have revealed its presence in the blood and urine of most humans, which may lead to long-term health effects. As the confined cavities of macrocycles can alter the physical and chemical properties of encapsulated guests, in this study, we investigated the formation of host-guest complexes between C-methylresorcin[4]arene and OXB. Combined experimental (NMR spectroscopy, UV/vis absorption, and fluorescence spectroscopy) and theoretical investigation confirmed the formation of a weak host-guest complex that had a 1 : 1 stoichiometry. Furthermore, skin permeation testing revealed that complexation by C-methylresorcin[4]arene significantly reduced the skin permeation of OXB which can potentially limit the harmful effects of this organic sunscreen.
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Frequency-dependent absorption coefficient spectrum and refractive index spectrum of alpha endosulfan, a kind of persistent organic pollutants, are presented in the terahertz frequency region by terahertz (THz) time-domain spectroscopy (TDS). The spectral features in the THz region have a number of unique characteristic absorption peaks. The result demonstrates that THz-TDS is a promising method to identify materials. Then we adopted density functional calculation method to analyze theoretic absorption coefficients of single alpha endosulfan molecule within 0.2-2 THz. The results show that absorption peaks at 1.68, 1.91 THz in theoretical calculation correspond to 1.7, 1.88 THz in the experiment. Finally, vibrational modes and approximate assignments were discussed, showing that these matched peaks are caused by intramolecular vibrational modes of alpha endosulfan. Others might be related to intermolecular vibrational modes or combined vibrational modes.