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Edible mushrooms are rich in nutrients and bioactive compounds, but their browning affects their quality and commercial value. This article reviews various methods to inhibit polyphenol oxidase (PPO)-induced browning in mushrooms. Physical methods such as heat treatment, low temperatures, irradiation, and ultrasound effectively reduce PPO activity but may affect mushroom texture and flavor. Chemical inhibitors, including synthetic chemicals and natural plant extracts, provide effective PPO inhibition but require careful monitoring of their content. Biological methods, including gene editing and microbial fermentation, show promise in targeting PPO genes and enhancing antioxidant production. Combining these methods offers a comprehensive strategy for preserving mushroom quality, extending shelf life, and maintaining nutritional value. PRACTICAL APPLICATION: These approaches can be applied in the food industry to improve post-harvest mushroom preservation, enhance product quality, and reduce waste, benefiting both producers and consumers. Further research and innovation are needed to optimize the practical application of these methods in large-scale processing and storage conditions.
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In this paper, for the sake of enhancing the security of wireless transmission, we proposed a novel system based on spatial and direction modulation (SDM) combined with generalized spatial modulation (GSM) which is aided by covert information mapping (CIM), termed as the CIM-GSDM system. In such a system, the legitimated user is equipped with distributed receivers so as to demodulate the conveyed signal by exploiting its indices while disturbing eavesdroppers for information security. More specifically, part of the information is modulated into the indices of the legitimated distributed receiver subsets with the aid of the mapped covert information and the interference matrix, while another part of the message is arranged by conventional amplitude-phase modulation. The proposed system can reap the benefits from both GSM and CIM to make eavesdropper suffer great mixture. Furthermore, the detection scheme and theoretical analysis of error performance are discussed as well. The simulation results exhibit that the bit error rate (BER) performance of legitimate user is much better than that of the eavesdropper while the proposed scheme improves the security compared to the original CIM-SDM system at the same spectral efficiency.
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This study successfully synthesized hydrogels by modifying chitosan with water-soluble and carboxyethyl groups, followed by crosslinking with oxidized carboxymethyl cellulose (OCMC). Structural analyses substantiated the establishment of robust imine linkages between the amino and aldehyde groups, affirming the hydrogel's architecture. Using scanning electron microscopy and texture analysis, it was observed that incorporating water-soluble chitosan significantly increased the hydrogel's porosity and hardness. Simultaneously, the addition of carboxyethyl groups enhanced the network structure, rendering it more compact and thereby improving the hydrogel's mechanical strength. The adsorption performance of the carboxyethyl chitosan (CEC)/OCMC hydrogel towards methylene blue was meticulously evaluated, demonstrating a substantial enhancement in adsorption capacity from 7.74 mg/g to 39.57 mg/g following the carboxyethyl modification of chitosan. Adsorption kinetics and isotherm analysis indicated that the adsorption behavior of the hydrogel followed the pseudo-second-order kinetic model and the Langmuir isotherm model. Furthermore, the maximum adsorption capacity of the hydrogel for methylene blue was predicted to be 111.60 mg/g using the Langmuir isotherm model.
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Objective: To investigate the effect of silencing GDP dissociation inhibitor 2 (GDI2) on colorectal cancer development and possible mechanisms based on transcriptomic analysis. Methods: The differences in the expression levels of GDI2 in normal colorectal tissues and tumor tissues of colorectal cancer (CRC) patients were detected. The correlation of GDI2 expression levels with survival and clinical characteristics of CRC patients was analyzed. The effects of GDI2 expression levels on the biological functions of CRC cells were examined by CCK-8 assay, plate clone formation assay, wound healing assay, and Transwell assay. The effect of GDI2 on the proliferation and growth of xenograft tumors was investigated by a xenograft tumor model of CRC in nude mice. Based on transcriptomics, we explored the possible mechanisms and associated pathways of the effect of silencing GDI2 on CRC cells. Cellular experiments and Western blot assays were performed to verify the potential mechanisms and related pathway of GDI2 action on CRC. Results: The expression levels of GDI2 in CRC tissues and cells were higher than those in normal tissues and cells. The expression level of GDI2 correlated with clinical characteristics such as lymphatic metastasis, tumor stage, tumor volume, and lymphocyte count. Silencing of GDI2 reduced the proliferative activity and migration and invasion ability of CRC cells, as well as inhibited the proliferation of CRC xenograft tumors. The differentially expressed genes were significantly enriched in biological processes such as cell cycle arrest and the p53 signaling pathway after GDI2 silencing. The percentage of G0/G1 phase cells in CRC cells was increased after silencing GDI2 as verified by flow cytometry. RAB5A was highly associated with the p53 pathway and could interact with TP53 via the ZFYVE20 protein. The mutual binding between GDI2 protein and RAB5A protein was verified by immunoprecipitation assay. Silencing GDI2 while overexpressing RAB5A reversed the reduced proliferation, migration, and invasion ability as well as cell cycle arrest of CRC cells. Meanwhile, the addition of p53 signaling pathway inhibitor Pifithrin-α (PFT-α) also reversed the biological effects of silencing GDI2 on CRC cells. The p-p21 and p-p53 protein expression levels were significantly greater in the sh-GDI2 group than in the sh-NC group. However, the p-p21 and p-p53 protein expression levels were reduced after silencing GDI2 while overexpressing RAB5A. Conclusion: Silencing GDI2 activates the p53 signaling pathway by regulating RAB5A expression levels, which in turn induces cell cycle arrest and ultimately affects the proliferative activity, migration, and invasive ability of CRC cells.
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Preparing stable n-type flexible single-walled carbon nanotube (SWCNT)-based thermoelectric films with high thermoelectric (TE) performance is desirable for self-powering wearable electronics but remains a challenge. Here, the interface regulation and thermoelectric enhancement mechanism of ferrocene derivatives on polyethylenimine/single-walled carbon nanotube (PEI/SWCNT) composite films have been explored by doping ferrocene derivatives (f-Fc-OH) into PEI/SWCNT films. The results show that the introduction of f-Fc-OH leads to the formation of "thorn" structures on the surfaces of SWCNT bundles via hydrophilic and hydrophobic interactions, the generated energy-filtering effect improves the thermoelectric properties of the PEI/SWCNT film, and the f-Fc-OH-doped PEI/SWCNT (f-Fc-OH/PEI/SWCNT) achieves the highest room-temperature power factor of 182.22 ± 8.60 µW m-1 K-2 with a Seebeck coefficient of -64.28 ± 0.96 µV K-1 and the corresponding ZT value of 4.69 × 10-3. The Seebeck coefficient retention ratio of the f-Fc-OH/PEI/SWCNT nearly remained 68% after being exposed to air for 3672 h, while the PEI/SWCNT film changed from n-type to p-type after being exposed to air for about 432 h. In addition, the temperature-dependent thermoelectric properties show that the f-Fc-OH/PEI/SWCNT achieves a high power factor of 334.57 µW m-1 K-2 at 353 K. Finally, a flexible TE module consisting of seven pairs of p-n junctions is assembled using the optimum composite film, which produces an open-circuit voltage of 42 mV and a maximum output power of 4.32 µW at a temperature gradient of 60 K. Therefore, this work provides guidance for preparing stable n-type SWCNT-based composite films with enhanced thermoelectric properties, which have potential applications in flexible generators and wearable electronic devices.
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The surge in advanced imaging techniques has generated vast biomedical image data with diverse dimensions in space, time and spectrum, posing big challenges to conventional compression techniques in image storage, transmission, and sharing. Here, we propose an intelligent image compression approach with the first-proved semantic redundancy of biomedical data in the implicit neural function domain. This Semantic redundancy based Implicit Neural Compression guided with Saliency map (SINCS) can notably improve the compression efficiency for arbitrary-dimensional image data in terms of compression ratio and fidelity. Moreover, with weight transfer and residual entropy coding strategies, it shows improved compression speed while maintaining high quality. SINCS yields high quality compression with over 2000-fold compression ratio on 2D, 2D-T, 3D, 4D biomedical images of diverse targets ranging from single virus to entire human organs, and ensures reliable downstream tasks, such as object segmentation and quantitative analyses, to be conducted at high efficiency.
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Compressão de Dados , Semântica , Compressão de Dados/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , AlgoritmosRESUMO
Brain-wide profiling of diverse biological components is fundamental for understanding complex brain pathology. Despite the availability in whole-brain imaging, it is still challenging to conduct multiplexed, brain-wide analysis with current tissue clearing techniques. Here, we propose SOLID, a hydrophobic tissue clearing method that can minimize tissue distortion while offering impressive clearing performance. SOLID achieves high-quality imaging of multi-color labeled mouse brain, and the acquired datasets can be effectively registered to the Allen Brain Atlas via commonly-used algorithms. SOLID enables generation of neural and vascular maps within one mouse brain, as well as tracing of specific neural projections labeled with viruses. SOLID also allows cross-channel investigations of ß-amyloid plaques and neurovascular lesions in the reconstructed all-in-one panorama, providing quantitative insights into structural interactions at different stages of Alzheimer's disease. Altogether, SOLID provides a robust pipeline for whole-brain mapping, which may widen the utility of tissue clearing techniques in diverse neuroscience research.
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Doença de Alzheimer , Encéfalo , Placa Amiloide , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Animais , Camundongos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Placa Amiloide/patologia , Placa Amiloide/metabolismo , Algoritmos , Mapeamento Encefálico/métodos , Camundongos Endogâmicos C57BL , Humanos , MasculinoRESUMO
The volatile components of Atractylodis Rhizoma have obvious pharmacological effects and are considered to be the main dry components of Atractylodis Rhizoma. The differences of different processed products of Atractylodis Rhizoma were analyzed from the perspective of volatile oil changes to explain the reasons for dryness reduction and efficacy increase of Atractylodis Rhizoma after processing. HS-GC-MS technology was used to obtain the volatile components of raw Atractylodis Rhizoma, bran-fried Atractylodis Rhizoma, roasted Atractylodis Rhizoma, and rice-water processed Atractylodis Rhizoma under four different processes, and then SIMCA software was used to analyze the volatile oil components of Atractylodis Rhizoma and its different processed products. A total of 87 volatile components were identified in the HS-GC-MS results. A total of 76 volatile components were identified in raw products; 79 volatile components were identified in bran-fried Atractylodis Rhizoma; 70 volatile components were identified in Zhangbang rice-water processed Atractylodis Rhizoma; 81 volatile components were identified in roasted Atractylodis Rhizoma; 78 volatile components were identified in Hunan rice-water processed Atractylodis Rhizoma; 73 volatile components were identified in Jilin rice-water processed Atractylodis Rhizoma, and 77 volatile components were identified in Shanghai rice-water processed Atractylodis Rhizoma. Through multivariate statistical analysis, it was found that there were significant differences between the processed products of Atractylodis Rhizoma. Then, a total of 28 significant differential components between the symbiotic products and the six processed products were established by the OPLS-DA model. Among them, 11 volatile components that generally increased significantly after processing were α-pinene, phellandrene,(1S)-(+)-3-carene, o-isopropyltoluene, D-limonene, α-ocimene, α-isoterpinene, silphiperfol-5-ene,silphinene, γ-alkenyl, and germacrene B, which may be related to their synergistic effect. Five volatile components that generally decreased significantly after processing were ß-elemene, 1-methyl-4-(6-methylhept-5-en-2-yl) cyclohexa-1, 3-diene, ß-selinene,ß-sesquiphellandrene, and atractylon, which may be related to their dryness.
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Atractylodes , Medicamentos de Ervas Chinesas , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis , Rizoma , Atractylodes/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Rizoma/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Óleos Voláteis/química , Óleos Voláteis/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/químicaRESUMO
Chitosan, as a biomaterial, has increasingly garnered attention. However, its limited solubility in water-only dissolving in certain dilute acidic solutions-substantially restricts its broader application. In this investigation, chitosan underwent a solubilization modification to acquire water solubility, facilitating its dissolution in neutral aqueous mediums. Subsequently, this water-soluble chitosan (WSC) was interlinked with oxidized carboxymethyl cellulose (OCMC), characterized by varied oxidation extents, to synthesize hydrogels. Structural characterization verified the formation of imine bonds resulting from crosslinking interactions between the amino groups of water-soluble chitosan and the aldehyde groups of oxidized carboxymethyl cellulose. Employing performance characterization analysis, it was discerned that an increase in the oxidation level of the oxidized carboxymethyl cellulose corresponded to a denser hydrogel network architecture and the hardness increased from 3.01 N to 6.16 N. Moreover, the capacity of these hydrogels to adsorb methylene blue was meticulously examined. Notably, the hydrogel denoted as WSC/66%OCMC manifested an adsorption capability of 28.08 mg/g for methylene blue. Analytical findings from adsorption kinetics and isotherm studies indicate that the adsorption mechanism of the WSC/66%OCMC hydrogel follows the pseudo-second-order kinetic model and corresponds to the Freundlich isotherm model.
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Carboximetilcelulose Sódica , Quitosana , Hidrogéis , Azul de Metileno , Oxirredução , Solubilidade , Água , Azul de Metileno/química , Hidrogéis/química , Hidrogéis/síntese química , Quitosana/química , Carboximetilcelulose Sódica/química , Água/química , Adsorção , CinéticaRESUMO
Clarification of the cytotoxic function of T cells is crucial for understanding human immune responses and immunotherapy procedures. Here, we report a high-throughput Bessel oblique plane microscopy (HBOPM) platform capable of 3D live imaging and phenotyping of chimeric antigen receptor (CAR)-modified T-cell cytotoxicity against cancer cells. The HBOPM platform has the following characteristics: an isotropic subcellular resolution of 320 nm, large-scale scouting over 400 interacting cell pairs, long-term observation across 5 hours, and quantitative analysis of the Terabyte-scale 3D, multichannel, time-lapse image datasets. Using this advanced microscopy platform, several key subcellular events in CAR-T cells are captured and comprehensively analyzed; these events include the instantaneous formation of immune synapses and the sustained changes in the microtubing morphology. Furthermore, we identify the actin retrograde flow speed, the actin depletion coefficient, the microtubule polarization and the contact area of the CAR-T/target cell conjugates as essential parameters strongly correlated with CAR-T-cell cytotoxic function. Our approach will be useful for establishing criteria for quantifying T-cell function in individual patients for all T-cell-based immunotherapies.
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Imageamento Tridimensional , Imunoterapia Adotiva , Microtúbulos , Receptores de Antígenos Quiméricos , Linfócitos T , Humanos , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Imageamento Tridimensional/métodos , Imunoterapia Adotiva/métodos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Microtúbulos/metabolismo , Linhagem Celular Tumoral , Sinapses Imunológicas/imunologia , Sinapses Imunológicas/metabolismo , Citotoxicidade Imunológica , Actinas/metabolismo , Microscopia/métodos , FenótipoRESUMO
Tissue-clearing techniques have revolutionized the field of biological imaging by rendering biological specimens transparent and enabling inside optical detection. Light-sheet fluorescence microscopy (LSFM) is a powerful tool for three-dimensional imaging of large biological samples. Combining tissue-clearing techniques with LSFM has advanced the efficient 3D visualization of these samples. A crucial challenge with LSFM is the requirement for the objective to operate within the clearing reagent, which can cause aberrations. To address this issue, we introduce a novel, to our knowledge, approach for the flexible design of the solid immersion refractive meniscus lens (SIMlens), facilitating the use of air objectives with cleared samples. Compared to the previous SIMlens, this method not only eliminates aberrations but also offers customized options for enhancing the numerical aperture and working distance of the objective lens, achieving at least a 10% improvement. We have demonstrated the feasibility of this new method using mouse brain samples.
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Lentes , Microscopia de Fluorescência , Animais , Camundongos , Microscopia de Fluorescência/métodos , Encéfalo/diagnóstico por imagem , Imageamento TridimensionalRESUMO
In this study, an innovative ratiometric fluorescence and smartphone-assisted visual sensing platform based on blue-yellow dual-emission carbon dots (BY-CDs) was constructed for the first time to determine brilliant blue. The BY-CDs was synthesized via a facile one-step hydrothermal process involving propyl gallate and o-phenylenediamine. The synthesized BY-CDs exhibit favorable water solubility and exceptional fluorescence stability. Under excitation at 370 nm, BY-CDs show two distinguishable fluorescence emission bands (458 and 558 nm). Upon addition of brilliant blue, the fluorescence intensity at 558 nm exhibited a significant quenching effect attributed to fluorescence resonance energy transfer (FRET), while the fluorescence intensity at 458 nm was basically unchanged. The prepared BY-CDs can effectively serve as a ratiometric nanosensor for determining brilliant blue with the ratio of fluorescence intensities at 458 and 558 nm (F458/F558) as response signal. In addition, the developed ratiometric fluorescence sensor exhibits a noticeable alteration in color from yellow to green under UV light with a wavelength of 365 nm upon addition of varying concentrations of brilliant blue, which provides the possibility of visual detection of brilliant blue by a smartphone application. Finally, the BY-CDs based dual-mode sensing platform successfully detected brilliant blue in actual food samples and achieved a desirable recovery rate. This study highlights the merits of fast, convenient, economical, real-time, visual, high accuracy, excellent precision, good selectivity and high sensitivity for brilliant blue detection, and paves new paths for the monitoring of brilliant blue in real samples.
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To understand neural basis of animal behavior, it is necessary to monitor neural activity and behavior in freely moving animal before building relationship between them. Here we use light sheet fluorescence microscope (LSFM) combined with microfluidic chip to simultaneously capture neural activity and body movement in small freely behaving Drosophila larva. We develop a transfer learning based method to simultaneously track the continuously changing body posture and activity of neurons that move together using a sub-region tracking network with a precise landmark estimation network for the inference of target landmark trajectory. Based on the tracking of each labelled neuron, the activity of the neuron indicated by fluorescent intensity is calculated. For each video, annotation of only 20 frames in a video is sufficient to yield human-level accuracy for all other frames. The validity of this method is further confirmed by reproducing the activity pattern of PMSIs (period-positive median segmental interneurons) and larval movement as previously reported. Using this method, we disclosed the correlation between larval movement and left-right asymmetry in activity of a group of unidentified neurons labelled by R52H01-Gal4 and further confirmed the roles of these neurons in bilateral balance of body contraction during larval crawling by genetic inhibition of these neurons. Our method provides a new tool for accurate extraction of neural activities and movement of freely behaving small-size transparent animals.
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Larva , Aprendizado de Máquina , Neurônios , Postura , Animais , Larva/fisiologia , Neurônios/fisiologia , Postura/fisiologia , Microscopia de Fluorescência/métodos , Drosophila melanogaster/fisiologia , Drosophila/fisiologia , Movimento/fisiologia , Comportamento Animal/fisiologiaRESUMO
AIM: To investigate the association between central serous chorioretinopathy (CSC) and Helicobacter pylori (Hp) by summarizing all available evidence. METHODS: The Scopus, Embase, EBSCO, PubMed, Web of Science, and Cochrane Library databases for all relevant studies published from inception to October 2022 were searched, and manually searched for relevant reference lists as a supplement. Studies investigating the association between CSC and Hp infection were included. Finally, 8 case-control studies were included in the Meta-analysis after study selection. RESULTS: The results showed no significant correlation between Hp infection and CSC [odds ratio (OR) 1.89, 95% confidential interval (CI) 0.58-6.15, I 2=96%, P=0.29]. After subgroup analysis based on the degree of development of the study (developing/developed countries), it was found that the results of the two subgroups were the same as the whole, and no significant difference between the two subgroups existed. Meta-regression showed that the effect of sample size on heterogeneity among studies was more prominent (P<0.01, adjusted R 2=89.72%), which can explain 89.72% of the sources of heterogeneity. CONCLUSION: This Meta-analysis reveals no significant correlation between Hp infection and CSC, which still warrants further well-designed extensive sample studies to reach a more reliable conclusion and promote a better understanding of the treatment of CSC.
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Escherichia coli MLB (MG1655 ΔpflB ΔldhA), which can hardly grow on glucose with little succinate accumulation under anaerobic conditions. Two-stage fermentation is a fermentation in which the first stage is used for cell growth and the second stage is used for product production. The ability of glucose consumption and succinate production of MLB under anaerobic conditions can be improved significantly by using acetate as the solo carbon source under aerobic condition during the two-stage fermentation. Then, the adaptive laboratory evolution (ALE) of growing on acetate was applied here. We assumed that the activities of succinate production related enzymes might be further improved in this study. E. coli MLB46-05 evolved from MLB and it had an improved growth phenotype on acetate. Interestingly, in MLB46-05, the yield and tolerance of succinic acid in the anaerobic condition of two-stage fermentation were improved significantly. According to transcriptome analysis, upregulation of the glyoxylate cycle and the activity of stress regulatory factors are the possible reasons for the elevated yield. And the increased tolerance to acetate made it more tolerant to high concentrations of glucose and succinate. Finally, strain MLB46-05 produced 111 g/L of succinic acid with a product yield of 0.74 g/g glucose. SYNOPSIS.
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BACKGROUND: Disinfection byproducts (DBPs) have been shown to impair thyroid function in experimental models. However, epidemiological evidence is scarce. METHODS: This study included 1190 women undergoing assisted reproductive technology (ART) treatment from the Tongji Reproductive and Environmental (TREE) cohort from December 2018 to August 2021. Serum thyrotropin (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were measured as indicators of thyroid function. FT4/FT3 and TSH/FT4 ratios were calculated as markers of thyroid hormone homeostasis. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), the two most abundant HAAs, in urine were detected to assess individual DBP exposures. RESULTS: After adjusting for relevant covariates, positive associations were observed between urinary TCAA concentrations and serum TSH and TSH/FT4 levels (e.g., percent change = 5.82 %, 95 % CI: 0.70 %, 11.21 % for TSH), whereas inverse associations were found for serum FT3 and FT4 (e.g., percent change = -1.29 %, 95 % CI: -2.49 %, -0.07 % for FT3). There also was a negative association between urinary DCAA concentration and serum FT4/FT3 (percent change = -2.49 %, 95 % CI: -4.71 %, -0.23 %). These associations were further confirmed in the restricted cubic spline and generalized additive models with linear or U-shaped dose-response relationships. CONCLUSION: Urinary HAAs were associated with altered thyroid hormone homeostasis among women undergoing ART treatment.
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Glândula Tireoide , Humanos , Feminino , Adulto , Tiroxina/sangue , Tri-Iodotironina/sangue , Tireotropina/sangue , Hormônios Tireóideos/sangue , Testes de Função Tireóidea , Desinfetantes , Acetatos , ChinaRESUMO
This paper presents the formation of a self-healing hydrogel prepared by carboxyethyl modification of chitosan and crosslinking with oxidized sodium alginate. Concurrently, the incorporation of Ca2+ facilitated the formation of "calcium bridges" through intricate coordination with carboxyl moieties, bolstering the attributes of the hydrogel. Various characterization methods, including scanning electron microscopy, texture analysis, and rheological measurements, demonstrated that the introduction of carboxyethyl groups resulted in a more compact hydrogel network structure and improved the hardness and elasticity. The addition of Ca2+ helped to further enhance the mechanical performance of the hydrogel and increase its thermal stability. Then, the adsorption capacity was also investigated, showing adsorption capacities of 46.17 mg/g methylene blue and 46.44 mg/g congo red for carboxyethyl chitosan/oxidized sodium alginate hydrogel, a four-fold increase for congo red versus chitosan/oxidized sodium alginate hydrogel. In addition, the adsorption behavior of CEC/OSA/2%Ca2+ hydrogel can be well described by pseudo-second-order kinetic model and Langmuir adsorption isothermal model. Compared to traditional hydrogels, CEC/OSA/2%Ca2+ hydrogel shows superior mechanical strength, enhanced thermal stability, and improved adsorption capacity, which can effectively adsorb not only methylene blue but also congo red. These advancements demonstrate our hydrogel's innovative properties.
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Quitosana , Poluentes Químicos da Água , Quitosana/química , Alginatos/química , Hidrogéis/química , Vermelho Congo , Azul de Metileno/química , Adsorção , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de HidrogênioRESUMO
Solution-processed colloidal quantum dots (CQDs) are promising candidates for broadband photodetectors from visible light to shortwave infrared (SWIR). However, large-size PbS CQDs sensitive to longer SWIR are mainly exposed with nonpolar (100) facets on the surface, which lack robust passivation strategies. Herein, an innovative passivation strategy that employs planar cation, is introduced to enable face-to-face coupling on (100) facets and strengthen halide passivation on (111) facets. The defect density of CQDs film (Eg ≈ 0.74 eV) is reduced from 2.74 × 1015 to 1.04 × 1015 cm-3, coupled with 0.1 eV reduction in the activation energy of defects. The resultant CQDs photodiodes exhibit a low dark current density of 14 nA cm-2 with a high external quantum efficiency (EQE) of 62%, achieving a linear dynamic range of 98 dB, a -3dB bandwidth of 103 kHz and a detectivity of 4.7 × 1011 Jones. The comprehensive performance of the CQDs photodiodes outperforms previously reported CQDs photodiodes operating at >1.6 µm. By monolithically integrated with thin-film transistor (TFT) readout circuit, the broadband CQDs imager covering 0.35-1.8 µm realizes the functions including silicon wafer perspectivity and material discrimination, showing its potential for wide range of applications.
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Powdered infant formula (PIF) is prone to Cronobacter sakazakii (C. sakazakii) contamination, which can result in infections that endanger the lives of newborns and infants. Slightly acidic electrolytic water (SAEW) has shown antibacterial effects on a variety of foodborne pathogens and has a wide applicability in the food industry. Here, the antibacterial activity of SAEW against C. sakazakii and its use as a disinfectant on contact surfaces with high infection transmission risk were investigated. The inactivation of SAEW on C. sakazakii was positively correlated to the SAEW concentration and treatment time. The antibacterial effect of SAEW was achieved by decreasing the intracellular adenosine triphosphate (ATP), K+, protein, and DNA contents of C. sakazakii, reducing the intracellular pH (pHin) and destroying the cell morphology, which led to inactivation of C. sakazakii ultimately. To test the applicability of this study, the results showed that approximately 103 CFU/cm2 of C. sakazakii were successfully inactivated on stainless steel and rubber surfaces after a 30 mg/L SAEW treatment for 20 s. These results indicate the antibacterial mechanism and potential application of SAEW against C. sakazakii, as well as a new strategy for the prevention and control of C. sakazakii on stainless steel and rubber surfaces.