•Utilization of high volume fly ash in steam-cured cement mortars was investigated.•Both the early and late compressive strength of steam-cured mortars were enhanced by UFA.•Pore structure of ...steam-cured high volume FA blended composites was effectively refined by UFA.•The amount of CH after steam curing was generally lower than that with standard curing.•The MCL and Al/Si of C-S-H gels under steam curing were improved by UFA.
Utilization of high volume fly ash is generally limited in steam-cured concrete products due to the delayed strength development. In present work, ultrafine fly ash (UFA) with a median particle size of 2.3 μm was prepared with wet-grinding technology. The influence of different FA fineness, UFA content (30–70%) and curing regimes on the compressive strength and microstructure of steam-cured high volume fly ash cement composites were studied. Both the early and late compressive strength of steam-cured FA blended composites were enhanced by wet-milled UFA with replacement level as high as 50%, and the strength was even higher than that of pure cement group. Pore structure of steam-cured high volume FA blended composites was effectively refined by UFA. The amount of CH after steam curing was generally lower than that with standard curing. Furthermore, the main chain length and Al/Si of C-S-H gels under steam curing were improved by UFA. Compared with prolonging the curing duration, increasing the curing temperature seems more efficient for the incorporation of aluminum from fly ash into the calcium silicate hydrates.
This study aimed to explore the effect of curcumin and hydromorphone hydrochloride (HH) cotreatment on postoperative pain in rats. An incision + formaldehyde-induced pain rat model was established. ...Rats were treated with vehicle, curcumin, HH, or curcumin + HH. Paw mechanical withdrawal threshold and thermal withdrawal latency were measured at 1 d before surgery as well as 1 , 2 h, 1 , 3 , and 7 d after surgery to assess pain sensitivity. The L4-6 region of the spinal cord was collected from each rat at 2 h, 1 , 3 , and 7 d after surgery. Western blot analysis and immunohistochemical staining were carried out to detect the protein expression of pain-related genes. Quantitative real-time PCR and enzyme-linked immunosorbent assay were conducted to measure the expression and production of proinflammatory mediators. Compared with other groups, Curcumin + HH significantly reduced pain sensitivity in the model rats. Mechanistically, curcumin + HH suppressed protein expression of stromal cell-derived factor-1 (SDF-1), CXC chemokine receptor 4 (CXCR4), p-Akt, and c-fos while enhancing protein expression of nerve growth factor (NGF) in the dorsal root ganglia (DRG) of model rats. Curcumin + HH inhibited the expression and production of interleukin 1β (IL-1β), cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), and p65 nuclear factor kappa B (NF-κB) in the DRG. Coadministration of curcumin and HH alleviates incision + formaldehyde-induced pain in rats, possibly by suppressing the SDF-1/CXCR4 pathway and the production of proinflammatory mediators. Our results provide curcumin and HH cotreatment as a promising therapeutic strategy in the management of postoperative pain.
Cationic corn starch derivatives containing quaternary ammonium groups with a high degree of substitution were synthesized by reacting corn starch with glycidyltrimethylammonium chloride (GTAC) in a ...homogeneous manner using 1-butyl-3-methylimidazolium chloride (BMIMCl) as a reaction medium. The influence of reaction time, reaction temperature, the amount of catalyst NaOH and molar ratio of GTAC/anhydroglucose units in starch on the degree of substitution (DS) of products was investigated. The maximum DS value obtained in the optimum reaction condition was up to 0.99. Furthermore, the structure of cationic starch derivatives was characterized by means of Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), thermal analysis and
1H NMR spectroscopy. The results showed that the ordered crystalline structure of native starch was largely destroyed during the dissolution and functionalization of starch in the ionic liquid BMIMCl, leading to an uniform etherification reaction to be carried out under the homogeneous reaction conditions.
In order to improve the safety and quality of lactose-free milk (LFM) Maillard reaction products (MRPs), this study used raw cow’s milk as raw material and lactase hydrolysis to prepare LFM, which ...was heat-treated using pasteurization and then placed in storage temperatures of 4 °C, 25 °C and 37 °C to investigate the changes in the Maillard reaction (MR). The results of the orthogonal test showed that the optimal conditions for the hydrolysis of LFM are as follows: the hydrolysis temperature was 38 °C, the addition of lactase was 0.03%, and the hydrolysis time was 2.5 h. Under these conditions, the lactose hydrolysis rate reached 97.08%, and the lactose residue was only 0.15 g/100 g as determined by high-performance liquid chromatography (HPLC), complying with the standard of LFM in GB 28050–2011. The contents of furoamic acid and 5-hydroxymethylfurfural were determined by high-performance liquid chromatography, the color difference was determined by CR-400 color difference meter, and the internal fluorescence spectrum was determined by F-320 fluorescence spectrophotometer. The test results showed that the variation range of furosine in lactose-free milk after pasteurization was 44.56~136.45 mg/100g protein, the range of 5-hydroxymethylfurfural (HMF) was 12.51~16.83 mg/kg, the color difference ranges from 88.11 to 102.53 in L*, from −0.83 to −0.10 in a*, and from 1.88 to 5.47 in b*. The furosine content of LFM during storage at 4, 25, and 37 °C ranged from 44.56 to 167.85, 44.56 to 287.13, and 44.56 to 283.72 mg/100 g protein, respectively. The average daily increase in protein content was 1.18–3.93, 6.46–18.73, and 15.7–37.66 mg/100 g, respectively. The variation range of HMF was 12.51~17.61, 12.51~23.38, and 12.51~21.1 mg/kg, and the average daily increase content was 0.03~0.07, 0.47~0.68, and 0.51~0.97 mg/kg, respectively. During storage at 4 °C, the color difference of LFM ranged from 86.82 to 103.82, a* ranged from −1.17 to −0.04, and b* ranged from 1.47 to 5.70. At 25 °C, color difference L* ranges from 72.09 to 102.35, a* ranges from −1.60 to −0.03, b* ranges from 1.27 to 6.13, and at 37 °C, color difference L* ranges from 58.84 to 102.35, a* ranges from −2.65 to 1.66, and b* ranges from 0.54 to 5.99. The maximum fluorescence intensity (FI) of LFM varies from 131.13 to 173.97, 59.46 to 173.97, and 29.83 to 173.97 at 4, 25, and 37 °C. In order to reduce the effect of the Maillard reaction on LFM, it is recommended to pasteurize it at 70 °C—15 s and drink it as soon as possible during the shelf life within 4 °C.
The effects of Steam Flash-Explosion (SFE) on the physicochemical properties and molecular structure of high-temperature denatured defatted rice bran protein isolate (RBPI) were investigated. The ...mechanism of SFE treatment on high-temperature denatured defatted RBPI was revealed. The analysis of the physical and chemical properties of RBPI showed that the surface hydrophobicity, characteristic viscosity, and thermal stability of rice bran protein isolate were significantly affected by the pressure of saturated steam and pressure holding time. Under the conditions of 2.1 MPa and 210 s, the surface hydrophobicity index decreased significantly from 137.5 to 17.5, and the characteristic viscosity increased significantly. The peak temperature of denaturation decreases from 114.2 to 106.7 °C, and the enthalpy of denaturation decreases from 356.3 to 231.4 J/g. The higher structure (circular dichroic spectrum and endogenous fluorescence spectrum) of rice bran protein isolate was analyzed by volume rejection chromatography (SEC). The results showed that steam flash treatment could depolymerize and aggregate RBPI, and the relative molecular weight distribution changed greatly. The decrease in small molecules with poor solubility was accompanied by the increase in macromolecules (>550 kDa) soluble aggregates, which were the products of a Maillard reaction. The contents of free sulfhydryl and disulfide bonds in high-temperature rice bran meal protein isolate were significantly increased, which resulted in the increase in soluble aggregates containing disulfide bonds. Circular dichroism (CD) analysis showed that the α-helix content of the isolated protein was significantly decreased, the random curl content was increased, and the secondary structure of the isolated protein changed from order to disorder. The results of endogenous fluorescence spectroscopy showed that the high-temperature rice bran meal protein isolate was more extended, tryptophan was in a more hydrophilic microenvironment, the fluorescence intensity was reduced, and the tertiary structure was changed. In addition, the mean particle size and net surface charge of protein isolate increased in the aqueous solution, which was conducive to the development of the functional properties of the protein.
The Split Bregman method (SBM), a popular and universal CS reconstruction algorithm for inverse problems with both l1-norm and TV-norm regularization, has been extensively applied in complex domains ...through the complex-to-real transforming technique, e.g., MRI imaging and radar. However, SBM still has great potential in complex applications due to the following two points; Bregman Iteration (BI), employed in SBM, may not make good use of the phase information for complex variables. In addition, the converting technique may consume more time. To address that, this paper presents the complex-valued Split Bregman method (CV-SBM), which theoretically generalizes the original SBM into the complex domain. The complex-valued Bregman distance (CV-BD) is first defined by replacing the corresponding regularization in the inverse problem. Then, we propose the complex-valued Bregman Iteration (CV-BI) to solve this new problem. How well-defined and the convergence of CV-BI are analyzed in detail according to the complex-valued calculation rules and optimization theory. These properties prove that CV-BI is able to solve inverse problems if the regularization is convex. Nevertheless, CV-BI needs the help of other algorithms for various kinds of regularization. To avoid the dependence on extra algorithms and simplify the iteration process simultaneously, we adopt the variable separation technique and propose CV-SBM for resolving convex inverse problems. Simulation results on complex-valued l1-norm problems illustrate the effectiveness of the proposed CV-SBM. CV-SBM exhibits remarkable superiority compared with SBM in the complex-to-real transforming technique. Specifically, in the case of large signal scale n = 512, CV-SBM yields 18.2%, 17.6%, and 26.7% lower mean square error (MSE) as well as takes 28.8%, 25.6%, and 23.6% less time cost than the original SBM in 10 dB, 15 dB, and 20 dB SNR situations, respectively.
This study of vegetation coverage in Jiamusi City provides theoretical support for local urban development, land use, and ecological environmental protection. Based on the land cover data and Landsat ...remote sensing image data from 2000 to 2020, the vegetation cover and land use data of Jiamusi City were extracted. The study includes the following aspects: (1) an analysis of the spatio-temporal changes in vegetation coverage; (2) analysis of the land use situation in Jiamusi City; and (3) investigation of the impact of natural and human factors on vegetation coverage in Jiamusi City using the Geodetector model. The results show that (1) over the past 20 years, the vegetation coverage of Jiamusi has shown a decreasing trend, declining from 25.22% in 2000 to 17.13% in 2020, representing a decrease of 32%. In terms of spatial distribution, the areas of Fuyuan City and Tongjiang City have experienced more significant decreases in vegetation coverage, decreasing by 73.6% and 54.0%, respectively. (2) The land use pattern of Jiamusi City has undergone significant changes during the study period; except for paddy fields (PF), unused land (UL), and construction land (CL), the areas of all the land categories have decreased. The ranking of the single land use dynamic degree in terms of magnitude is as follows: PF, UL, CL, dry farmland (DF), vegetation coverage land (VCL), and wetland (WET). (3) The changes in vegetation coverage were influenced by both natural and human activities and, according to the Geodetector results, the main influencing factors were CL and DF. The key findings of this study emphasize the need for comprehensive land use planning and ecological environmental protection that focus on sustainable development and conservation practices, and lay the groundwork for future ecosystem management and urban planning efforts in Jiamusi City.
The emergence of numerous variants of SARS-CoV-2, the causative agent of COVID-19, has presented new challenges to the global efforts to control the COVID-19 pandemic. Here, we obtain two ...cross-neutralizing antibodies (7D6 and 6D6) that target Sarbecoviruses' receptor-binding domain (RBD) with sub-picomolar affinities and potently neutralize authentic SARS-CoV-2. Crystal structures show that both antibodies bind a cryptic site different from that recognized by existing antibodies and highly conserved across Sarbecovirus isolates. Binding of these two antibodies to the RBD clashes with the adjacent N-terminal domain and disrupts the viral spike. Both antibodies confer good resistance to mutations in the currently circulating SARS-CoV-2 variants. Thus, our results have direct relevance to public health as options for passive antibody therapeutics and even active prophylactics. They can also inform the design of pan-sarbecovirus vaccines.
The coal fly ash (CFA) in the present study contains a high content of gallium, which is categorized as a strategic metal. Gallium extraction from CFA is an important step toward its reutilization. ...Two different processes for gallium extraction were systematically investigated and compared. The effects of mixed acid, microwave power, microwave digestion time, the amount of HNO
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, HF, and HCl were studied. The results revealed that although both open wet digestion and microwave-assisted digestion could successfully leach gallium, the former method consumed a longer time. The microwave-assisted digestion was a time-saving way but required the use of HCl. Compared to previous studies, the processes proposed in this article can greatly reduce environmental pollution and cost as they halved the use of acids.
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