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As changes in the melting behavior of starch in the extruder affect the physical properties of the extrudate. exploring the melting behavior during starch extrusion is of great significant for the production of ideal thermoplastic starch-based materials. Effects of different extrusion temperatures (60, 70, 80, 90 and 100 ℃) on the structure and physicochemical properties of corn starch were investigated. The results showed that under high temperature and mechanical shear, the starch granules were fragmented and the granule size was reduced. The hydrogen bonds within starch molecules were broken, which made starch easier to bind with water molecules, to improve the hydration properties of thermoplastic starch (TPS). As the temperature increased, the content of amylose increased, and the relative crystallinity (RC) and double-helix order (DO) decreased, indicating that the long-range and short-range ordered structures of corn starch were destroyed during heating. The high temperature treatment of the extruder reduced the enthalpy of TPS and destroyed the ability of starch paste to form a gel network. The samples had a weak gelation behavior, and the rigidity and elasticity were weakened. In conclusion, the temperature of twin-screw extrusion changed the starch particle structure, crystalline structure, hydration and rheological properties to different degrees. This study has provided theoretical basis and new ideas for extruding high quality thermoplastic starch materials.

Objective: This study aimed to reduce the setting time of yogurt, improve the texture of yogurt and evaluate the effect of pea peptides on the quality of coagulated yogurt. Methods: Different amounts（0, 0.50%, 0.75%, 1.00%, 1.25%, 1.50%）of pea peptides were added into milk powder to prepare pea peptide yogurt, and then the setting time, titer acidity, and texture properties of the yogurt were investigated. Results: The results showed that when the amount of pea peptides added was less than or equal to 1.25%, the yogurt setting time could be significantly shortened. When the amount of pea peptide added was 1%, the effect was significant by shortening the coagulation time for 32 min. The addition of pea peptides significantly increased the acidity of yogurt. When the addition amount of pea peptides was less than 1%, the springiness and chewiness of the yogurt were significantly reduced, and the gumminess, cohesiveness, and resilience were significantly increased, which improved the textural properties of the yogurt. Conclusion: The addition of pea peptides to the yogurt fermentation substrate can shorten the fermentation period and enhance the quality of the final product.

Objective: Explore the protective effect of Procambarus clarkii shell bioactive peptides （PCSBP） on oxidative stress injury in the organism. Methods: This study using alkaline protease hydrolysis method to prepare bioactive peptides and measured their antioxidant activity in vitro. Subsequently, the protective effects of PCSBP on oxidative stress injury in zebrafish under fasting stress was analyzed. Results: The PCSBP showed potential antioxidant capacity in vitro, with scavenging rates of DPPH radicals and hydroxyl radicals at （46.35±1.32）% and （75.22±2.18）%. The final body weight, body length and muscle amino acid content of zebrafish were decreased under fasting stress, but the growth performance and muscle amino acid content of Zebrafish were effectively improved after taking PCSBP. The muscle tissue structure showed that the myofiber gap widened and ruptured in zebrafish after fasting. The myofiber were arranged neatly, with complete morphology and structure after PCSBP ingestion, and no obvious rupture was observed. In terms of anti-oxidative stress, PCSBP significantly enhanced the activities of superoxide dismutase （SOD）, catalase （CAT）, glutathione peroxidase （GSH-PX）, and glutathione （GSH） content in zebrafish muscle, and also decreased the production of malondialdehyde （MDA） and protein carbonyl （PC）, which were oxidative damage indexes. Further analysis revealed that PCSBP significantly up-regulated the expression of antioxidant signaling molecule nrf2 mRNA, down-regulated keap1 expression, and increased the transcriptional expression of downstream antioxidant enzyme genes, which effectively ameliorated the oxidative stress damage in muscle of zebrafish. Conclusion: Bioactive peptides derived from crayfish shell has a protective effect on oxidative stress injury in zebrafish and can be used as a potential antioxidant.

Starch and protein are two important components in food system. The interactions between starch and protein have important influence on the structure, physicochemical properties of starch and the texture and digestibility of starch-based food. In recent years, the effect of exogenous protein on starch-protein interaction in mixed system and its application have become a hot research topic in the field of food. This article reviews the interaction mode between starch and protein, the effect of protein on physicochemical properties （gelatinization properties, retrogradation properties, rheological properties, thermal properties and texture properties） and microstructure of starch-protein mixed system, summarizes the regulation effect of protein on digestibility of starch in mixed system and its mechanism, and presents the application of the mixed system in food processing, aiming to clarify the mechanism of interactions between starch and protein and provide theoretical reference for the research and development of starch-based food.

Objective: This study aimed to control the degree of crosslinking and etherification in the preparation process of crosslinked hydroxypropyl starch and improve the product performance. Methods: Waxy corn starch was used as a raw material to prepare the composite modified starch （hydroxypropyl distarch phosphate, HDP） under alkaline conditions, during which process sodium trimetaphosphate （STMP） and propylene oxide （PO） was used as the cross-linker and etherifying agent, respectively. The effects of the addition level of STMP and PO on the properties of the Brabender viscosity behavior, transparency and freeze-thaw stability of waxy corn starch were investigated. Results: Combined with the preliminary laboratory exploration and the optimization of this study, a HDP with improved thermal stability, transparency and freeze-thaw stability and lowered gelatinization temperature was obtained. The preparation conditions of HDP were as follows: in the case that the amount of sodium trimetaphosphate was 0.30 g/100 g and cross-linking reaction time was 45 minutes, and the amount of propylene oxide added was 6 mL/100 g and the etherification time was 90 minutes. Conclusion: Compared to raw waxy corn starch, the cross-linked and etherified starches with decreased gelatinization temperature and improved freeze-thaw stability, thermal stability and gelling properties are observed.

Objective: This study aimed to improve the utilization value of scallop processing by-products, by analyzing the antioxidant activity of its protein hydrolysates. Methods: The processing by-products of Argopecten irradians were used as raw materials, and the proteins were extracted by alkali extraction and acid precipitation, alkali extraction and ammonium sulfate precipitation and low temperature ethanol denaturation precipitation. Then the proteins were analyzed by SDS-PAGE. Pepsin, flavourzyme, dispase and alcalase were used to hydrolyze the protein, and the antioxidant activities of the hydrolysate products were analyzed. The molecular weight distribution, amino acid composition and hydroxyproline content of dispase hydrolysates were further analyzed. Results: The purity of protein obtained by alkaline ammonium sulfate precipitation method was the highest, reaching 91.16%, with the optima electrophoretic results. All the four hydrolysates had DPPH, ABTS, hydroxyl radical scavenging ability and reducing ability, and the dispase hydrolysate showed the highest antioxidant ability, especially hydroxyl radical scavenging rate, which reached （77.24±1.87）%. The hydrolysate of dispase contained 15 kinds of amino acids such as aspartic acid, with a total content of 84 g/100 g, and the content of hydroxyproline reached （11.82±0.09）%. Conclusion: The protein obtained from the by-products of scallop processing by alkaline extraction and ammonium sulfate precipitation, and its dispase hydrolysates have optimal antioxidant activity and high nutritional value, which can be further developed as antioxidant functional food.

This review summarized the research progress on the preparation methods of nano-delivery systems, the types of proteins used to construct plant polyphenol nano-delivery carriers, and the modification of nano-delivery carriers by cross-linking agents domestically and internationally. The development of protein-based plant polyphenol nano-delivery carriers in the food field was also prospected.

Objective: This study focuses on the effects of twin-screw extrusion on the functional properties and structure of pea protein. Methods: The color change of pea protein extrudates were analyzed by automatic colorimeter, the water holding capacity and emulsifying characteristics of pea protein were analyzed by chemical analysis. The microstructure of pea protein and its extrudates were observed by scanning electron microscope, and the secondary structure of the extrudates were analyzed by Fourier transform infrared spectroscopy. Results: After extrusion treatment, no significant difference was found in the color of pea protein, indicating that the pea protein had a better product color and the water holding capacity was significantly reduced （P＜0.05）, with the emulsibility and emulsification stability significantly increased （P＜0.05）. Scanning electron microscope showed that the microstructure changed obviously, resulting in protein aggregates with compact structure. The infrared spectrum showed that no new characteristic peaks appeared after extrusion treatment, but the secondary structure conversion occurred; β-sheet and α-helix structure transformed into β-turn and random coil structure, and the structural stability increased. Conclusion: After extrusion treatment, the pea protein retained its original product color, emulsification characteristics were significantly improved, the structure was dense and stability was enhanced.

The article summarized the classification of flavonoids and their physiological activities in recent years. The classification, adsorption mechanism and application effects of nano-solid-phase extractant in the separation and purification of flavonoids were reviewed, and the development trend of the separation and purification on flavonoids by nano-solid-phase extractant was analyzed.

This review introduced the classification, structure and physical and chemical properties of dietary fiber, and summarized the relevant research literature on the modification methods and physicochemical properties of dietary fiber at home and abroad in recent years. The development direction of the physicochemical properties of dietary fiber and its modification methods were also prospected, in order to provide a theoretical reference for its efficient and comprehensive utilization.

Deficits in upper and lower urinary tract function, which include detrusor overactivity, urinary incontinence, detrusor-sphincter dyssynergia, and polyuria, are among the leading issues that arise after spinal cord injury (SCI) affecting quality of life. Given that overproduction of urine (polyuria) has been shown to be associated with an imbalance in key regulators of body fluid homeostasis, the current study examined the timing of changes in levels of various relevant hormones, peptides, receptors, and channels post-contusion injury in adult male Wistar rats. The results show significant up- or downregulation at various time points, beginning at 7 days post-injury, in levels of urinary atrial natriuretic peptide, serum arginine vasopressin (AVP), kidney natriuretic peptide receptor-A, kidney vasopressin-2 receptor, kidney aquaporin-2 channels, and kidney epithelial sodium channels (?- and ?-, but not ?-, subunits). The number of AVP-labeled neurons in the hypothalamus (supraoptic and -chiasmatic, but not paraventricular, nuclei) was also significantly altered at one or more time points. These data show significant fluctuations in key biomarkers involved in body fluid homeostasis during the post-SCI secondary injury phase, suggesting that therapeutic interventions (e.g., desmopressin, a synthetic analogue of AVP) should be considered early post-SCI.

Objective: To improve the development and utilization rate of Lycium barbarum in the saline-alkali land of the Yellow River Delta. Methods: Ultraviolet spectrophotometer was used to determine the scavenging effect of Lycium barbarum oligosaccharide on free radicals and its effect on the growth curve and pH value of Bifidobacterium adolescentis, so as to determine its antioxidant performance and the ability to proliferate probiotics. Results: The concentration of Lycium barbarum oligosaccharide reached 2.0 mg/mL, the maximum scavenging rates of DPPH·, ABTS+ and hydroxyl radical reached （65.32±0.03）%, （99.93±0.05）% and （21.86±0.01）%, respectively, when the concentration was between 0.1~0.5 mg/mL, it showed good total reducing power. The OD value of Bifidobacterium adolescentis increased with the increase of Lycium barbarum oligosaccharide concentration, and the pH value was negatively correlated with the cell concentration. Conclusion: Lycium barbarum oligosaccharides show strong antioxidant activity and the ability to proliferate probiotics.

In this article, a 6 mm thick high-strength steel (HSS) was butt laser-MAG welded using nickel alloy wires as the cladding layer. By preparing the cladding layer on the groove, the microstructure and properties of the weld were adjusted. OM, XRD, SEM, and tensile and impact experiments were used to study the structure and mechanical properties of the welded joints. The results show that the weld structure with the cladding layer corresponds to austenite, while the microstructure of the conventional laser arc hybrid welded joint is a combination of austenite and martensite. Additionally, the tensile specimens of the welded joint are fractured at the weld. The fracture strength of the nickel alloy layer is 809 MPa, and the fracture strength of the conventional laser arc hybrid welded joint is 1149 MPa. The low temperature toughness (−40 °C) of conventional laser arc hybrid welded joint is 6.2J. The low temperature toughness (−40 °C) of prefabricated welded joints with laser-filled cladding has increased to 40.8 J, and this proves to be an effective method to improve the low temperature toughness of the welded joint.

In order to solve problem of high cost of running management of relay-contactor control mode commonly used in sewage pumping station at present, the paper proposed a design scheme of automatic control system for sewage pumping station which takes S7-300 PLC as core, introduced the system's composition and control principle, and expounded design of the system's hardware and software. The system uses PLC to control a soft-starter to drive four motors, so as to eliminate influence on motors caused by direct starting. Besides, the system can automatically choose the most reasonable running state according to different situations, and communicate with upper computer to upload data and receive control orders. The practical application showed that the system is stable in running and improves water purifying efficiency of sewage pumping station.

Abstract Previously, a damascene process based on nanoimprint lithography has been proposed (Schmid G M, et al. in J Vac Sci Technol B 24(3) 1283, 2006) to greatly reduce the fabrication steps of metal interconnection in integrated circuit. For such a process to become a viable technique, a mold having two pattern levels with precise alignment between them must be fabricated first. To this end, this work demonstrates a “self-aligned” fabrication process where the two pattern levels would be perfectly aligned if ignoring the noise during e-beam writing. The process is based on one EBL on a bi-layer resist stack, with the sensitivity for the top layer much higher than that of the bottom layer, which enables separate pattern transfer of the two pattern levels. Using ZEP-520A and poly(dimethylglutarimide) (PMGI) resists, we fabricated pillars having a diameter of 150 nm sitting on ridges having a width of 1.5 μm, which can be used to create via-holes and trenches for IC interconnect by nanoimprint lithography. The current process can also find applications in other areas that require two-level patterning with precise alignment between them.

Diabetic nephropathy (DN) is one of the most common causes of end-stage renal failure. This study was performed to determine the effect of Dantonic Pill (DP) treatment on β-catenin expression in a rat model of streptozotocin- (STZ-) induced early-stage DN, with irbesartan treatment as a positive control. Including an analysis of the general metabolic index and renal function, immunohistochemical staining and reverse transcription real-time PCR for β-catenin were performed in the renal cortex of the rat models every 4 weeks. After the treatments of DP and irbesartan, the albuminuria level, kidney weight/body weight, and thickness of the glomerular basement membrane were decreased, but the expression of β-catenin was not downregulated in the renal cortex. The effective drug target of DP to ameliorate albuminuria and renal hypertrophy should not inhibit the upregulated expression of β-catenin in rats with STZ-induced early-stage diabetic damage.

Based on the characteristics of hot water supply in bathroom, this article proposes a new hybrid energy hot water supply system. The programmable logic controller(PLC) as the master controller was adopted in this system, which could automatically detect and storage main thermal physical of the system, such as temperature, water level, solar radiation intensity, power consumption and so on. The active thermal utilization technology of solar energy, air-source heat pump technology, solar energy intensive natural ventilation technology and low temperature hot water floor radiant heating technology were organically integrated in this system, which has the advantages of energy conservation and environment protection, high automation, safe and reliable operation, etc. At the same time, it can make good use of electric power cost between on-peak and off-peak, and promote the optimal allocation of power resources and reduce the cost, which can achieve the goal of intelligent control and energy saving.