High capacity and selective adsorption of Congo red by cellulose-based aerogel with mesoporous structure: Adsorption properties and statistical data simulation.

Large quantities of organic dyes are discharged into the environment, causing serious damage to the ecosystem. Therefore, it is urgent to develop inexpensive adsorbents to remove organic dyes. A novel cellulose-based aerogel (MPPA) with 3D porous structure was prepared by using cassava residue (cellulose) as basic construction blocks, doping ferroferric oxide (Fe3O4) for magnetic separation, and applying polyethyleneimine (PEI) as functional material for highly efficient and selective capture of Congo red (CR). MPPA exhibited porous network structure, numerous active capture sites, nontoxicity, high hydrophilicity, and excellent thermal stability. MPPA showed superior adsorption property for CR, with an equilibrium adsorption capacity of 2018.14 mg/g, and still had an adsorption property of 1189.31 mg/g after five recycling procedures. In addition, MPPA has excellent selectivity for CR in four binary dye systems. The adsorption behavior of MPPA on CR was further explored using a multilayer adsorption model, EDR-IDR hybrid model and AOAS model. Electrostatic potential and independent gradient models were used to further verify the possible interaction between MPPA and CR molecules. In conclusion, MPPA is a promising adsorbent in the field of treating anionic dyes.

Conditional Deletion of Foxg1 Delayed Myelination during Early Postnatal Brain Development.

FOXG1 (forkhead box G1) syndrome is a neurodevelopmental disorder caused by variants in the Foxg1 gene that affect brain structure and function. Individuals affected by FOXG1 syndrome frequently exhibit delayed myelination in neuroimaging studies, which may impair the rapid conduction of nerve impulses. To date, the specific effects of FOXG1 on oligodendrocyte lineage progression and myelination during early postnatal development remain unclear. Here, we investigated the effects of Foxg1 deficiency on myelin development in the mouse brain by conditional deletion of Foxg1 in neural progenitors using NestinCreER;Foxg1fl/fl mice and tamoxifen induction at postnatal day 0 (P0). We found that Foxg1 deficiency resulted in a transient delay in myelination, evidenced by decreased myelin formation within the first two weeks after birth, but ultimately recovered to the control levels by P30. We also found that Foxg1 deletion prevented the timely attenuation of platelet-derived growth factor receptor alpha (PDGFRα) signaling and reduced the cell cycle exit of oligodendrocyte precursor cells (OPCs), leading to their excessive proliferation and delayed maturation. Additionally, Foxg1 deletion increased the expression of Hes5, a myelin formation inhibitor, as well as Olig2 and Sox10, two promoters of OPC differentiation. Our results reveal the important role of Foxg1 in myelin development and provide new clues for further exploring the pathological mechanisms of FOXG1 syndrome.

Micro-mechanism insights into the adsorption of anionic dyes using quaternary ammonium-functionalised chitosan aerogels.

The development of adsorbents with outstanding adsorption capacities, wide versatility, and excellent recyclability for the removal of organic dyes remains a challenge. In this study, a quaternised chitosan-based aerogel (QCSA) was fabricated via a facile method to effectively treat concomitant anionic dyes. Porous QCSA with high hydrophilicity, nontoxicity, excellent thermal stability, and sustainability exhibits adsorption properties superior to most previously reported adsorbents. The equilibrium adsorption capacities for Congo red, Sunset yellow, and Methyl orange were 1259.6, 550.2, and 607.5 mg/g, respectively. Notably, the spent QCSA exhibits excellent cyclic performance. The multilayer adsorption, external-internal mass transfer resistance, and adsorption on the active site models were employed to enable a more accurate description of the dynamic characteristics, confirming that double-layer chemisorption was the dominant process. A quantitative analysis of the electrostatic potential and the independent gradient model further verified that electrostatic interactions, hydrogen bonding, and van der Waals forces led to the highly efficient adsorption of dye molecules. Therefore, the eco-friendly and recyclable QCSA is a promising adsorbent for trapping anionic dyes from aquatic systems.

Hyperbranched polyethyleneimine-functionalised chitosan aerogel for highly efficient removal of melanoidins from wastewater.

Melanoidins are hazardous dark-coloured substances contained in molasses-based distillery wastewater. Adsorption is an effective approach to eliminate melanoidins from wastewater. However, melanoidin adsorption capacities of available adsorbents are unsatisfactory, which seriously limits their practical application. A hyperbranched polyethyleneimine-functionalised chitosan aerogel (HPCA) was fabricated as an effective adsorbent for melanoidin scavenging. HPCA demonstrated superior melanoidin adsorption efficiency because of its high specific surface area, abundant amino functional groups, and high hydrophilicity. Melanoidin removal rate of HPCA was 94.95%, which remained at 91.45% after 5 cycles. Notably, using the Langmuir isothermal model, the maximum melanoidin adsorption capacity of HPCA was determined to be 868.36 mg/g, surpassing those of most of previously reported adsorbents. Toxicity experiments indicated that HPCA can be considered a safe adsorbent with excellent biocompatibility that hardly threatens aquatic organisms. The efficient melanoidin removal of HPCA was attributed to electrostatic attraction, H-bonding, and van der Waals force. However, the adsorption might be predominantly controlled by electrovalent interaction between protonated amino groups of HPCA and carboxyl/carboxylate groups of melanoidins. Two novel models, namely, external diffusion resistance-internal diffusion resistance mixed model and adsorption on active site model, were employed to describe the dynamic mass transfer characteristics of melanoidin adsorption by HPCA.

(3-Chloro-2-hydroxypropyl) trimethylammonium chloride and polyethyleneimine co-modified pomelo peel cellulose-derived aerogel for remelt syrup decolorization in sugar refining.

The crucial need for quality refined sugar has led to the development of advanced adsorbents, with a focus on the decolorization of remelt syrup. In this study, (3-chloro-2-hydroxypropyl) trimethylammonium chloride and polyethyleneimine co-modified pomelo peel cellulose-derived aerogel (CP-PPA) was fabricated, and synthetic melanoidins were used as model colorants of remelt syrup to evaluate the validity and practicality of CP-PPA for eliminating colored impurities. Integrating abundant amine-functionalized groups (quaternary ammonium and protonated amine) within the pomelo peel-derived aerogel directionally captured electronegative melanoidins via electrostatic interactions. Furthermore, the active sites, types, and relative strength of the weak interactions between CP-PPA and melanoidins were determined using density functional theory simulations. CP-PPA exhibited an excellent equilibration adsorbing capacity for capturing melanoidins of 749.51 mg/g, and a removal efficiency of 93.69 %. Additionally, the adsorption mechanism was thoroughly examined in an effort to improve the economy of the sugar refinement industry.

miR319 and its target TCP4 involved in plant architecture regulation in Brassica napus.

Plant architecture is a collection of genetically controlled crop productivity and adaptation. MicroRNAs (miRNAs) have been proved to function in various biological processes, but little is known about how miRNA regulates plant architecture in rapeseed (Brassica napus L.). In this study, four small RNA libraries and two degradome libraries from shoot apex of normal and rod-like plants were sequenced. A total of 639 miRNA precursors and 16 differentially expressed miRNAs were identified in this study. In addition, 322 targets were identified through degradome sequencing. Among them, 14 targets were further validated via RNA ligase-mediated 5' rapid amplification of cDNA ends. Transgenic approach showed that increased TCP4 activity in Arabidopsis resulted in premature onset of maturation and reduced plant size along with early flowering and shortened flowering time. miR319-OE lines in Brassica napus exhibited serrated leaves and abnormal development of shoot apical meristem (SAM), which led to the deformed growth of stem and reduced plant height. In conclusion, our study lays the foundation for elucidating miRNA regulate plant architecture and provides new insight into the miR319/TCP4 module regulates plant architecture in rapeseed.

Preparation of highly efficient p-doped porous camellia shell-based activated carbon and its adsorption of carotenoids in camellia oil.

The vegetable oil industry is limited by the high cost of the refining process, and the camellia shells (CS) are beneficial to the development of the industry as a biomass raw material for camellia oil decolorization. In this study, CS-based p-doped porous activated carbon (CSHAC) obtained after the pyrolysis of H3PO4-laden CS-hydrochar (CSH) was used for the adsorption of carotenoids in camellia oil. The results showed that the adsorption efficiency of CSHAC for carotenoids was 96.5% compared to 67-87% for commercial decolorizers, and exhibited a fast adsorption rate (20 min). The results of adsorption isotherms indicated that the adsorption of carotenoids on CSHAC occurred through a multi-layer process. Furthermore, the analysis of adsorption kinetics showed that the adsorption of carotenoids by CSHAC was a complex process involving physical and chemical reactions, and chemisorption was the dominant kinetic mechanism. This superior performance of CSHAC in adsorbing carotenoids was attributed to its micro-mesoporous structure, hydrophobicity, and numerous active sites.

Clarification of Limed Sugarcane Juice by Stainless Steel Membranes and Membrane Fouling Analysis.

The performance of stainless steel membranes with pore sizes of 100 and 20 nm in clarifying limed sugarcane juice was investigated under different operating conditions. An increase in transmembrane pressure (TMP) for the 20 nm membrane from 2 to 5 bar led to an increase in the average flux from 146.6 Lm-2 h-1 to 187.8 Lm-2 h-1 (approximately 9 h). The increase in crossflow velocity from 2 to 5 m/s led to an increase in the average flux from 111.9 Lm-2 h-1 to 158.1 Lm-2 h-1. The increase in temperature from 70 °C to 90 °C caused an increase in the average flux from 132.8 Lm-2 h-1 to 148.6 Lm-2 h-1. Simultaneously, the test produced a high-quality filtered juice with an average of 1.26 units of purity rise. The purity increased with time, and a 99.99% reduction in turbidity and an average 29.3% reduction in colour were observed. In addition, four classic filtration mathematical models and scanning electron microscopy (SEM) analyses suggested that cake formation is the main mechanism for flux decline. Fourier transform infrared (FTIR) spectrometry and energy-dispersive X-ray (EDX) spectrometry indicated that organic fouling is the main foulant. This study demonstrates the potential of stainless steel membranes as filters for the clarification of raw sugarcane juice.

Preparation of quaternary ammonium magnetic chitosan microspheres and their application for Congo red adsorption.

In this study, novel green in situ quaternary-ammonium-functionalized magnetic chitosan microspheres (IQMCM) were synthesised. The resulting adsorbent was characterised by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, X-ray photoelectron spectroscopy, and zeta potential analysis. The characterization results indicated that the IQMCMs possessed spherical morphology and superior specific thermal stability, magnetic properties, and surface charges. Batch adsorption experiments revealed that the adsorption capacities of the IQMCM microspheres to Congo red (CR) was 630.21 mg/g at a dosage of 0.15 g/L, temperature of 333 K, pH of 5.0, and initial dye concentration of 100 mg/L, and the corresponding removal rate reached 94.53 %. According to the kinetics, adsorption isotherms, and thermodynamics experiment results, the adsorption of CR dye coincided with a spontaneous endothermic monolayer chemisorption process. After saturated adsorption, this magnetic adsorbent could be rapidly separated from water and reused with little adsorption capacity loss. Overall, these results show that IQMCMs are potentially applicable in wastewater treatment.

Tailored production of lignin-containing cellulose nanofibrils from sugarcane bagasse pretreated by acid-catalyzed alcohol solutions.

In this study, sugarcane bagasse was pretreated with acid-catalyzed alcohols, i.e., ethanol (AE), ethylene glycol (AEG) and glycerol (AG) to prepare pulps for producing lignin-containing cellulose nanofibrils (LCNF) with tailored properties, such as hydrophilicity/hydrophobicity and dispersion stability. The results showed that AG-LCNF had the highest lignin content of 16% but relatively low hydrophobicity while AE-LCNF had a low lignin content of 11% but the highest hydrophobicity. LCNF diameter distribution, crystallinity, zeta potentials and thermal stability were also determined to understand the effects of pretreatment solvent. NMR analyses revealed that alcohols modified lignin at α-position by etherification and γ-position by esterification of aliphatic chains, subsequently affecting lignin oxidation by TEMPO in the LCNF production processes, LCNF properties and LCNF dispersion in different solvents. This study provided fundamental information in the design and tailored production of LCNF for various applications, such as manufacturing polymer composites and Pickering emulsions.

Waste preserved wood derived biochar catalyst for promoted peroxymonosulfate activation towards bisphenol A degradation with low metal ion release: The insight into the mechanisms.

The rational disposal of waste preserved wood is of great significance since its embedded metals (Cu, As, and Cr) pose potential threat to environment and human health. In this study, a biochar catalyst derived from waste preserved wood (PWB) was prepared for the degradation of bisphenol A (BPA) via peroxymonosulfate (PMS) activation. The PWB exhibited prominent catalytic degradation capability towards BPA compared with common wood derived biochar (CWB). Further tests and analysis elucidated that both radical species (OH) and non-radical species (1O2) were generated by the PWB/PMS system, whereas only 1O2 was detected in CWB/PMS system. Specifically, the metal compounds, especially metallic Cu in the PWB activated PMS via radical pathway, and the CO groups in the biochar generated the non-radical pathway, the coexistence of which resulted in higher BPA degradation rate in PWB/PMS system. It was also demonstrated that the heavy metal ion leaching (As and Cr) in PWB/PMS system was negligible. Furthermore, the biochar could effectively inhibit the leakage of oxidized Cu ions. This study provides a novel approach to prepare high-efficient carbocatalysts for organic pollutant degradation in water, which also enables the waste preserved wood with an environmental nondestructive mode of dispatch.

Ultrasound-Guided Stellate Ganglion Block Combined with Extracorporeal Shock Wave Therapy on Postherpetic Neuralgia.

OBJECTIVES: To evaluate the effect of ultrasound-guided stellate ganglion block combined with extracorporeal shock wave therapy (ESWT) on postherpetic neuralgia. METHODS: Thirty-six patients with craniofacial postherpetic neuralgia, whose skin lesions were healed and natural course more than 1 month, were selected for the study and then randomly divided into 3 groups: the ultrasound-guided stellate ganglion block group (group A, n = 12), the extracorporeal shock wave therapy group (group B, n = 12), and the combined treatment group (group C, n = 12). Each group received basic drug treatment. The Visual Analogue Scale (VAS) and the Pain Disability Index (PDI) were used to evaluate the clinical effects of the 3 groups of patients before treatment, after twice treatments, after treatment for four times, and after treatment for six times. RESULTS: The VAS and PDI were significantly declined in each group after the treatment (P < 0.05), and the declination in group C was more obvious than the other two groups (P < 0.05). After treatment for six times, the VAS score of group A, group B, and group C was 3.1 ± 1.2, 3.3 ± 1.3, and 1.9 ± 0.7, respectively. After treatment for six times, the PDI of group A, group B, and group C was 11.7 ± 8.4, 12.3 ± 7.8, and 4.6 ± 3.2, respectively. Three patients developed skin bruising and slight swelling, which were relieved by themselves. CONCLUSIONS: Ultrasound-guided stellate ganglion block combined with shock wave therapy could significantly improve the pain symptoms of patients with postherpetic neuralgia, which is a safe and effective treatment for postherpetic neuralgia.

The Flavonoid Biosynthesis and Regulation in Brassica napus: A Review.

Brassica napus is an important crop for edible oil, vegetables, biofuel, and animal food. It is also an ornamental crop for its various petal colors. Flavonoids are a group of secondary metabolites with antioxidant activities and medicinal values, and are important to plant pigmentation, disease resistance, and abiotic stress responses. The yellow seed coat, purple leaf and inflorescence, and colorful petals of B. napus have been bred for improved nutritional value, tourism and city ornamentation. The putative loci and genes regulating flavonoid biosynthesis in B. napus have been identified using germplasms with various seed, petal, leaf, and stem colors, or different flavonoid contents under stress conditions. This review introduces the advances of flavonoid profiling, biosynthesis, and regulation during development and stress responses of B. napus, and hopes to help with the breeding of B. napus with better quality, ornamental value, and stress resistances.

Removal of heavy metal ion cobalt (II) from wastewater via adsorption method using microcrystalline cellulose-magnesium hydroxide.

Microcrystalline cellulose (MCC), magnesium sulfate hexahydrate, and trisodium citrate were reacted in ammonia bath in an aqueous solution to prepare a MCC-magnesium hydroxide (MH) composite adsorbent, which was used to adsorb heavy metal Co(II) ion. The method of using MCC-MH to adsorb and remove Co(II) was studied under different pH values, adsorbent dosages, contact times, initial Co(II) ion concentrations, and temperatures. The optimal process parameters include an MCC-MH dosage of 2.5 mg/mL, a contact reaction equilibrium time of 50 min, a Co(II) solution pH of 6.0-8.0, an initial Co(II) concentration of 300 mg/L, and a temperature of 303 K. The removal rate of Co(II) solution by MCC-MH was as high as 97.67%, and the maximum adsorption capacity of MCC-MH reached 153.84 mg/g under these optimal conditions. The adsorption isotherm of Co(II) conformed to the Langmuir model, the kinetic data of Co(II) conformed to the pseudo-second-order kinetic model, and the adsorption of Co(II) by MCC-MH was a spontaneous endothermic reaction under the optimized conditions. Analytical studies showed that Co(II) adsorption on MCC-MH composites is affected by chemical adsorption and involves the influence of intraparticle diffusion to a certain extent.

Enhanced degradation of bisphenol A by mixed ZIF derived CoZn oxide encapsulated N-doped carbon via peroxymonosulfate activation: The importance of N doping amount.

In this study, mixed metal cobalt zinc oxide embedded nitrogen enriched porous carbon composites (CoZnO-PC) were prepared via pyrolyzing polyvinylpyrrolidone (PVP) encapsulated Co, Zn-bimetal centered zeolitic imidazolate frameworks (ZIF). The prepared composites were then used to activate peroxymonosulfate (PMS) for bisphenol A (BPA) removal in water. When mole ratio of Co/Zn was 2/1, the resulted Co2Zn1O-PC possessed spinel structure with prominent degradation capability, in which the introduction of Zn accelerated the PMS activation performance of Co through establishing bimetal synergistic interactions. Both radical and non-radical activation pathways were existed in the Co2Zn1O-PC/PMS system, in which Co2Zn1O dominated the radical pathway whereas PC dominated the non-radical way. Since PVP contained abundant nitrogen atoms and could form strong coordination interactions with the ZIF precursor, the introduction of PVP in the ZIF precursor prevented pore collapsing during pyrolysis process, as well as enhancing the nitrogen content in the pyrolzed composites, which significantly promoted the generation of singlet oxygen. With combined pathways, the Co2Zn1O-PC/PMS system showed a wide pH application range with promising mineralization rate. Meanwhile, the spinel-structured Co2Zn1O-PC was magnetically separable with desirable recyclability. This study presents a novel composite with remarkable performance for the removal of refractory organic pollutants in municipal wastewater.

Fe3C-porous carbon derived from Fe2O3 loaded MOF-74(Zn) for the removal of high concentration BPA: The integrations of adsorptive/catalytic synergies and radical/non-radical mechanisms.

In this study, novel Fe3C-porous carbon composites (Fe3C-C) were prepared via the pyrolysis of Fe2O3 loaded MOF-74(Zn), which could integrate both strong adsorption properties and excellent peroxymonosulfate (PMS) activating performance for the removal of bisphenol A (BPA) in water. Results indicated that the composite obtained at 1000 °C (Fe3C-C1000) exhibited optimal catalytic capability. Specifically, 0.1 mM BPA could be completely removed by 0.1 g/L Fe3C-C1000 within 10 min after the adsorption enrichment. Afterwards, the mechanism of Fe3C-C/PMS system was unveiled based on quenching tests, electron spin resonance analysis, electrochemical analysis, PMS consumption detection and solvent exchange (H2O to D2O) test. The BPA degradation pathways were also analyzed through identifying its decomposition intermediates. Results showed that the Fe3C and porous carbon constituents could activate PMS via radical and non-radical mechanisms respectively, and BPA was readily degraded through both pathways. Additionally, it was found that the Fe3C-C1000/PMS system could maintain conspicuous catalytic performance in a variety of complicated water matrices with wide pH application range and long-time use stability. This study suggests a new insight for the design and development of novel catalyst which can be used for the removal of refractory organic contaminants with high concentrations in water media.

Dynamics of nonspherical bubble in compressible liquid under the coupling effect of ultrasound and electrostatic field.

A model for a nonspherical bubble in a compressible liquid under the coupling effect of ultrasound and electrostatic field was developed in this study. The following assumptions are made: (1) the bubble undergoes adiabatic oscillation; (2) the gravity of the liquid is negligible; (3) the bubble is insulating. If the speed of sound approaches infinity (c→∞), the equation set is reduced to the equation set for an incompressible liquid. We found that, under ultrasonic irradiation coupled with electric stress, a nonspherical bubble cannot oscillate steadily in the liquid. The bubble is bound to collapse during several cycles. The presence of electric stress reduces the surface tension at the bubble wall, which produces a larger maximum bubble-radius during the rarefaction cycle and a smaller minimum bubble-radius during the compression cycle. Consequently, during the collapse, both the gas pressure and the temperature in the bubble center increase substantially, if the bubble is exposed to both ultrasound and electrostatic field instead of ultrasound alone. In addition, the cavitation threshold of the bubble within an electrostatic field decreases significantly, compared to the bubble without an electrostatic field. In general, bubble cavitation occurs more easily and violently in the liquid after the introduction of an electrostatic field.

Generation of mWasabi fluorescent protein-binding nanobodies.

mWasabi is a bright monomeric green fluorescent protein. It can be used as a fusion tag to monitor various biological events, e.g. protein localization. Here we report the selection of camelid-derived single-domain antibody fragments (nanobodies) against mWasabi. In this work, phage-display approach was employed to select the high affinity mWasabi-specific Nb (nanobodies). These nanobodies were able to recognize mWasabi or in a fused fashion with PD1. The interesting binding characteristics of these two mWasabi-specific nanobodies could be valuable for design new tools for cellular tracing or targeting based on the mWasabi-fusing protein in many different biological research fields.

Structural elucidation of high-molecular-weight alkaline degradation products of hexoses.

High-molecular-weight alkaline degradation products of hexoses (HMWHADPs) are colored substances in sugar solutions formed during sugar manufacturing process. These products may be occluded within sugar crystals and impart yellow or brown color to sucrose, thereby negatively affecting the quality of white sugar. Thus, the structural properties of HMWHADPs pose a significant scientific problem in the sugar industry. In the present study, the structural properties of HMWHADPs were investigated using nuclear magnetic resonance, zeta potential analyzer, energy-dispersive X-ray spectrometry, ultraviolet-visible spectra, and Fourier transform infrared spectroscopy. Results showed that HMWHADPs mainly contain carboxyl, aldehyde, alcoholic hydroxyl, conjugated double bonds, and saturated alkanes. Possible mechanisms of HMWHADP formation were proposed on the basis of structural property investigation. This study can be used as reference for future research and practice in developing effective methods for the removal of HMWHADPs from sugar solutions and prevention of their further formation in subsequent steps.

Study on quality characteristics of cassava flour and cassava flour short biscuits.

In this paper, the basic components, nutrient composition, and processing characteristics of cassava flour were determined. In addition, the effects of xanthan gum and inulin on the pasting properties, microstructure, and thermal properties of cassava flour were studied. Biscuits were prepared using cassava flour as the main raw material and the optimal technology and formula for the biscuits were determined by single-factor and orthogonal tests. The effects of xanthan gum and inulin on the quality of cassava flour short biscuits were also investigated, and volatile components in the biscuits were determined using electronic nose technique. The addition of xanthan gum improved the pasting properties and microstructure of cassava flour, and improved the taste and increased hardness and brittleness of the biscuits, making their quality similar to that of commercially available short biscuits. The addition of inulin inhibited the setback of starch and improved starch gelatinization. However, inulin was not suitable for processing of cassava flour biscuits as it decreased their hardness, brittleness, and taste. The optimal formula and baking conditions of cassava flour short biscuits were as follows: cassava flour 100 g, water 24 g, shortening 25 g, sugar 30 g, baking powder 0.6 g, salt 1 g, and egg 25 g; the surface fire and primer fire temperatures were 180°C, and the baking time was 9 min. In addition, although the main aroma volatile components present in cassava flour and low gluten wheat flour short biscuits were similar, the proportions of each component were different.