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The citronellol-rich Origanum vulgareessential oil (OEO), which exhibits excellent antioxidant and antimicrobial activities, has limited use in food packaging owing to its high volatility and instability. This problem can be solved using electrospinning. In this study, OEO was incorporated into the zein matrix via emulsion electrospinning. OEO was obtained by hydro-distillation; gas chromatography–mass spectrometry analysis revealed that citronellol (44.34%) was a predominant compound in OEO. Scanning electron microscopy images demonstrated that the fibers had a bead-free and uniform structure with a diameter ranging from 215 ± 36 to 260 ± 72 nm. The X-ray diffractograms indicate the amorphous structure of the zein fibers. Fourier transform infrared absorption spectroscopy revealed an interaction between OEO and zein. The addition of OEO to the zein nanofibers affected its secondary structure. Thermogravimetric analysis showed that the OEO-loaded (OEO/zein) nanofibers exhibited high thermostability and that the water contact angle was enhanced. The encapsulation efficiency and loading capacity were in the range of 71.56–85.8% and 8.88–40.93%, respectively. The antioxidant activity of the OEO/zein nanofibers ranged from 45.40% to 71.50%. The OEO/zein fibers displayed antimicrobial activity against Staphylococcus aureusand Escherichia coli. In conclusion, OEO/zein nanofibers are promising alternatives for active food packaging.

Covalent organic frameworks (COFs) create extended two-dimensional (2D) skeletons and aligned one-dimensional (1D) channels, constituting a class of novel π architectures with predesignable structural ordering. A distinct feature is that stacks of π building units in skeletons shape the pore walls, onto which a diversity of different units can be assembled to form various pore interfaces, opening a great potential to trigger a strong structural correlation between the skeleton and the pore. However, such a possibility has not yet been explored. Herein, we report reversible three-dimensional (3D) coalescence and interlocked actions between the skeleton and pore in COFs by controlling hydrogen-bonding networks in the pores. Introducing carboxylic acid units to the pore walls develops COFs that can confine water molecular networks, which are locked by the surface carboxylic acid units on the pore walls via multipoint, multichain, and multidirectional hydrogen-bonding interactions. As a result, the skeleton undergoes an interlocked action with pores to shrink over the x–yplane and to stack closer along the zdirection upon water uptake. Remarkably, this interlocked action between the skeleton and pore is reversibly driven by water adsorption and desorption and triggers profound effects on π electronic structures and functions, including band gap, light absorption, and emission.

In this paper, seven Metschnikowia pulcherrimastrains were isolated from different origins and evaluated for fermentation-related enzyme activities and fermentation characteristics using simulated grape juice. The impact of these strains on Viognierwines fermentation was further evaluated by analyzing their fermentation kinetics, enological parameters and untargeted metabolomics. Results showed that WG6 and WG13 strains had relatively high β-glucosidase, esterase, pectinase and protease activities. All M. pulcherrimahad a low utilization of fructose compared to S. cerevisiaeand that fermentation alone produced lactic acid but not acetic acid. In Viognierwines, the co-fermentation of all M. pulcherrimawith S. cerevisiaeresulted in higher concentrations of volatiles but lower concentrations of volatile fatty acids. In particular, WG13 strain enhanced to the maximum concentration of volatiles, including the elevation of higher alcohols, acids and esters, while WG6 strain not only enhanced the aroma by elevating the concentration of acetic acid esters and fatty acid esters, but also the taste. Metabolomics revealed that WG6 strain significantly increased the content of L-phenylalanine, fatty acids and dipeptides in co-fermented wines. Thus, co-fermented wines with WG6 strain and S. cerevisiaeachieved the best sensory evaluation through a relatively balanced increase in beneficial volatile and non-volatile substances. This research provides a theoretical basis for the synergistic effect of aroma and taste.

Purpose: The benefits of growth hormone (GH) therapy in Prader-Willi syndrome (PWS) children are well established, but there is still considerable controversy regarding whether GH treatment can improve cognitive, motor, and behavioral development in PWS children. The objectives of this meta-analysis were to quantitatively evaluate the effects of GH on cognitive, motor function, and behavioral development in PWS children. Methods: Randomized controlled trials (RCTs) examining the effects of GH on cognitive, motor, and behavioral development in PWS children were identified by searching the MEDLINE, EMBASE, and Cochrane Library databases. Intervention effects were represented by Hedges’g and pooled to calculate effect sizes using a random-effects model. Results: Ten relevant studies comprising data from 302 participants were finally included. We observed no significant difference in cognitive performance between the GH treatment group and the control group (p?=?0.197). GH treatment was shown to remarkably improve motor development in PWS children compared with the control treatment (p?<?0.001), with moderate positive treatment effects (Hedges’g [95% CI]?=?0.71 [0.38, 1.03]). There were no significant differences between the GH group and the control group based on objective assessments of behavioral development (p?=?0.53). Conclusions: The meta-analysis suggested that GH treatment had a significantly positive effect on motor development, with moderate treatment effects in PWS children; however, there was no evidence of effects on cognitive or behavioral development.

The effect of Mo additions on the microstructures and mechanical properties of CoCrNi alloys was investigated, meanwhile, ab initio calculations are performed to quantitatively evaluate the lattice distortion and stacking fault energy (SFE). The yield strength, ultimate tensile strength, and elongation of (CoCrNi) 97 Mo 3 alloy are 475 MPa, 983 MPa and 69 %, respectively. The yield strength is increased by ∼30 % and high ductility is maintained, in comparison with CoCrNi alloy. Besides the nano-twins and dislocations, the higher density of stacking faults is induced during the tensile deformation for (CoCrNi) 97 Mo 3 alloy. Ab initio calculation results indicate the mean square atomic displacement (MSAD) and SFE value of (CoCrNi) 97 Mo 3 alloy is 42.6 pm2 and -40.4 mJ/m2 at 0 K, respectively. The relationship between mechanical properties and MSAD, SFE for various multiple principal element alloys is discussed. [ABSTRACT FROM AUTHOR]

In metastable high-entropy alloys (HEAs), the decrease of phase stability enables the development of dual-phase microstructure (interface hardening) and occurrence of strain-induced martensitic transformation (transformation-induced hardening), which overcomes the strength–ductility trade-off. The stacking-fault energy (SFE) is closely related to the phase stability and plays a key role in controlling the underlying deformation mechanism and hence the mechanical performance of HEAs. Here, we review some approaches of SFE calculation, including theoretical and experimental methods as well as the factors affecting SFE. Several compositional systems related to metastable HEAs are also briefly reviewed. Furthermore, we show the unique microstructure and the structure–property relationship of the metastable HEAs. Furthermore, some potential research topics in the future are also proposed.

In metastable high-entropy alloys (HEAs), the decrease of phase stability enables the development of dual-phase microstructure (interface hardening) and occurrence of strain-induced martensitic transformation (transformation-induced hardening), which overcomes the strength–ductility trade-off. The stacking-fault energy (SFE) is closely related to the phase stability and plays a key role in controlling the underlying deformation mechanism and hence the mechanical performance of HEAs. Here, we review some approaches of SFE calculation, including theoretical and experimental methods as well as the factors affecting SFE. Several compositional systems related to metastable HEAs are also briefly reviewed. Furthermore, we show the unique microstructure and the structure–property relationship of the metastable HEAs. Furthermore, some potential research topics in the future are also proposed.

The aim of the present study was to investigate the effect of glutamine (Gln) on growth performance, biochemical parameters, and antioxidant capacity in broilers exposed to medium-term chronic heat stress. A total of 300 twenty-two-day-old Arbor Acres broilers (half male and female) were randomly divided into 5 groups. The control group was housed at normal temperature (24°C) and fed a basic diet; 4 heat-stressed groups were housed under cyclic high temperature (8 h at 34°C, 16 h at 24°C, daily) and fed the basic diet supplemented with 0, 0.5, 1.0, and 1.5% Gln, respectively. After 2 wk, broilers exposed to high temperature had significantly lower (P< 0.05) body weight (BW), body weight gain (BWG), feed intake (FI), serum total protein, glutathione (GSH), total superoxide dismutase (T-SOD) activity, and total antioxidant capacity (T-AOC), but higher (P< 0.05) feed-to-gain ratio (FGR), serum glucose, and malondialdehyde (MDA). Dietary supplementation with 1.0 and 1.5% Gln significantly increased (P< 0.05) BW, BWG, FI, and serum TP, whereas dietary 1.5% Gln also significantly decreased (P< 0.05) FGR and serum glucose, compared to the heat treatment control group. Dietary supplementation with 1.0 and 1.5% Gln significantly decreased (P< 0.05) serum MDA, but significantly increased (P< 0.05) serum GSH, T-SOD activity, and T-AOC compared to the heat treatment control group. This study suggests that dietary Gln improves growth performance, serum biochemical profile, and antioxidant capacity in heat-stressed broilers.

Schizonepeta annua(Pall.) Schischk. is an endemic annual plant from the Lamiaceae family and it has been employed to cure tra-cheitis in traditional herbal medicine. Its essential oil exhibited a strong antimicrobial and antioxidative effect. Next, high-performance thin-layer chromatography—bioautography was applied for investigation of the bioactive compounds of S. annua, and gas chromatography—quadrupole time-of-flight mass spectrometry was used to perform subsequent targeted identification of compounds. Three active components were characterized, and two of them were tentatively identified as thymol and carvacrol. S. annuahas the potential to be a good alternative for synthetic disinfectants and antioxidants.

Long-acting growth hormone (GH) has been developed to address the noncompliance and decreased efficacy associated with daily GH injections. We aimed to evaluate the efficacy and safety of long-acting GH replacement therapy in children with short stature. Randomized controlled trials (RCTs) that investigated the efficacy and safety of long-acting GH therapy in children with short stature in comparison with daily GH injections were searched in Medline, Embase, and the Cochrane Central Register of Controlled Trials. A random-effect model was used to pool data using mean difference and odds ratios (OR). (PROSPERO registration number: CRD42018111105). Seven relevant studies were finally included. Meta-analysis found there was no significant difference between high-dose long-acting GH and daily GH in terms of height velocity (HV) (mean difference (MD) = −0.10, 95% CI, −0.79 to 0.60, P= 0.79). Moreover, no significant difference was observed in height standard deviation scores (Ht SDS) between high-dose long-acting GH and daily GH (MD = −0.07, 95% CI, −0.18 to 0.03, P= 0.17). Treatment with high-dose long-acting GH significantly increased IGF-1 SDS when compared with daily GH (MD = 0.31, 95% CI, 0.06–0.56, P= 0.02). In safety assessment, no significant difference was observed in the incidence of adverse events between high-dose long-acting GH and daily GH (OR 1.42, 95% CI, 0.65–3.11, P= 0.38). There is no evidence to support differences in the effects of long-acting GH compared with those of daily GH. More RCTs that focus on the safety of high-dose long-acting GH treatment, especially the detection of adverse events caused by elevated levels of serum IGF-1, are needed in the future.

The emergence of long COVID as a COVID-19 sequela was largely syndromic in characterisation. Digital health technologies such as wearable devices open the possibility to study this condition with passive, objective data in addition to self-reported symptoms. We aimed to quantify the prevalence and severity of symptoms across collected mobile health metrics over 12 weeks following COVID-19 diagnosis and to identify risk factors for the development of post-COVID-19 condition (also known as long COVID).

To investigate the antagonistic cell injury effect and molecular mechanism of scutellarin (SCU) in hypoxia reoxygenation (HR) treated human cardiac microvascular endothelial cells (HCMECs).

In this study, a method for the qualitative analysis of small molecular compounds in Schizonepeta annua(Pall.) Schischkessential oil was established based on gas chromatography–quadrupole time-of-flight mass spectrometry. In addition to an automated search of the NIST library, the identification of oxygenated monoterpenes, phenolic esters, and phenolic compounds was achieved by two additional strategies. One strategy involved comparing the relative errors of accurate masses measured for ions in the experimental spectra with those calculated for fragments identified from the NIST database of candidate matches. The second strategy involved combination of the product ion scans and positive chemical ionisation spectra for structural elucidation. Overall, 95.45% of the total essential oil volatile chemical content of Schizonepeta annua(Pall.) Schischkwas identified, with phenolic monoterpenes dominating.

ABSTRACTThis study investigated the effects of glutamine (Gln) on meat quality, skeletal muscle antioxidant capacity and Gln metabolism in heat-stressed broilers. Three hundred 42-day-old broilers were randomly divided into five groups: a control group (23 ± 1°C), which was fed basal diet, and four experimental groups (34 ± 1°C), supplemented with 0, 5, 10, and 20 g Gln/kg of basal diet. The experiment lasted for 24 h. Compared with the control group, acute heat stress caused a significant reduction (p < .05) in meat pH, water-holding capacity (WHC), gumminess and hardness, and a significant increase (p < .05) in cooking loss (CL) and lightness (L*) values. However, dietary Gln (20 g/kg) increased (p < .05) meat pH, WHC, gumminess and hardness, but decreased (p < .05) meat CL and L* values in the acute heat-stressed group. In breast and thigh muscles, the acute heat stress group exhibited significantly (p < .05) higher concentrations of malondialdehyde (MDA), but significantly (p < .05) lower levels of Gln, glutamate and glutaminase than the control group; dietary 20 g/kg Gln significantly decreased (p < .05) MDA concentrations, while it increased (p < .05) glutathione, glutathione peroxidas, T-AOC, Gln, glutamate, and glutaminase levels in acute heat-stressed groups. Gln could increase meat quality by improving antioxidative capacity and Gln metabolism in heat-stressed broilers.

Graphite chip formation is important for the understanding of high speed milling of brittle graphite. This paper is aimed to reveal the influence of cutting conditions on the graphite chip formation in high speed milling. The relationship between the maximum undeformed chip thickness and cutting parameters was analyzed, and the influence of cutting parameters, tool geometry and milling patterns on the chip formation of brittle graphite was studied. It is concluded that the transitions of graphite chip formations were highly dependent on the undeformed chip thickness which is decided by the combination setting of feed per tooth and radial depth of cut. Big fractured block chip occurs more easily in up milling than down milling. Tool rake angle influences the chip formation according to the maximum undeformed chip thickness.

In order to find the reason of concrete cracking in some construction. The mechanical property and micro-analysis of cores were tested, which drilled from cracked concrete floor. The test results indicated that alkali–aggregate reaction occurred, leading to the cracks in concrete floor. X-ray diffraction and scanning electron microscope facilitate the occurrence analysis and evaluation of cracked concrete.

Taking different types of punching dies as examples, this paper analyses the assembly requirements of precision punching dies under different structural features, key technical problems need to solve, assembly process and so on; and introduces the main components assembly methods, main points and skills.

Taking the example of precise gasket blanking die, the author introduces that the key of compound die assembly is adjusting the gap between moulds which directly influences the quality of products and the dies lifetime. When assembling, one must assure the uniformity of the gap between the terrace and sunken die.

n this article, it mainly describes the use of extrusion production process as an example of the special shaft. It gives us a full analysis from the structure of the product, the material problems, the key technical problems needed to be solved, blank preparation processing and the process of extrusion forming. It also introduces the blank dimensions and the calculation method of the extrusion pressure. The method of blank lubrication processing and the process of designing extrusion mould.We are not unfamiliar with the center shaft of the bike. It is one of the important parts in bicycle bottom bracket. It is also a key part to determine the quality of the bicycle. Generally speaking, materials are used is 20 steel. The roughness of the surface is moderate. But the requirement of the product precision is high. We can get it by using mechanical processing method. But it is processing and the efficiency is low. While the utilization rate of mental material is low. So the production costs high. Because the parts production patch is large and the annual production is hundreds of thousands of pieces. In my opinion, it is more reasonable for us to adopt the technology of producing the parts with the cold extrusion precision molding process. Then we can save the materials, improve the efficiency of producing parts, lower the production parts and then meet the requirement of mass production.

A nonlinear finite element method is used to analyze the dynamic property of a five-storey reinforced concrete (RC) frame structure with and without carbon fiber reinforced plastic (CFRP). When the frame strengthened by CFRP, seismic performance of that is improved better than the frame without CFRP. The inter-story displacement angles of the frames with and without CFRP satisfy the seismic requirements from the results of earthquake transient analyses, when the frame is exposed to the frequent and rare earthquake.

In order to anlyse the compaction process of vibrating roller more accurately, this paper built a new 6-DOF Vibration system dynamic model under the coupling operating condition of intellectual vibratory roller considering the qualities of soilmass and applied the new model on a type of intellectual vibratory roller’ dynamic analysis. On that basis, we optimized the design parameter of this vibratory, and found out the optimum working parameters. It would realize the effective control of intellectual vibratory roller in the process of compaction, advance the density and compaction efficiency in compacting process, and improve comfortabilityg of the complete machine. At the same time, it also provided an effective numerical basis for the optimization design of vibratory roller.

In the paper, an approach, based on bounded-error estimation via interval analysis, is presented to identify viscous damping coefficient and Coulomb friction coefficient of such-rod pumping system of directional well. The approach assumes the error of colleted output data of suck-rod pumping system is bounded. Hence, the problem of parameter estimation can be viewed as that of set inversion, which will be effectively solved via interval analysis. The main advantage of the proposed method in comparison with the traditional estimation methods is that, as it is global, it bypasses the problem of initialization. Moreover, the method avoids amount error due to transformation of measurement output data. An identification example is given to show the correctness and efficiency of the proposed method.

Through analyzing the forming process of cylindrical parts with bars, put forward conditions of such parts upsetting pressure bulging, How to use a mold to complete the forming of such a complex of bars, and describes the structure of the mold and work processes. By reducing the stamping process, improve productivity and reduce production costs, in the application easy to spread, and achieved good economic benefits.

AtERF4 (ethylene response factor) is a negative regulator in jasmonic acid mediated signal transduction pathway and ethylene mediated signal transduction pathway of Arabidopsis.It could respond to abscisic acid (ABA) and ethylene stimulus. ATSYR1gene encodes a syntaxin localizing at the plasma membrane in Arabidopsis, which can be induced by abiotic stress. To identify mutation lines for gene functional analysis, real-time PCR was employed to detect the expression level of AtERF4 and ATSYR1in homozygous T-DNA insertion mutant line, respectively. Real-time PCR is a powerful tool which can be used to detect steady-state mRNA levels specifically, sensitively and reproducibly. Comparing to other forms of quantitative RT-PCR, the amount of amplified products can be detected by real-time PCR instantly and thus is a preferable alternative. In this study, RNA with T-DNA inserting into exon could be detected in AtERF4 knock-out mutation line. The results indicated that AtERF4 had been trucked in transcription level. On the other hand, T-DNA inserting into the promoter of gene ATSYR1had no effect on reducing the expression level of ATSYR1gene. Further molecular and phenotype studies now are ongoing to clarify the potential consequences of AtERF4 and ATSYR1deficiency in Arabidopsis.

Compare with horizontal support, the bracing systems of pile and oblique brace have obvious advantages in deep excavation. However, because diagonal brace is inconvenient for the construction of structure , the use of this system is limited. Based on the coordinating space role of this support system, planning the excavation and exchanging brace and construction structure as a whole, according to the minimum potential result of a piecewise space unit, this paper introduces the model which are both applied to the excavation stage and exchanging brace stage, and derives the calculation method in relationship to the length of sub region. optimal design of the whole process was proposed for this form. Finally, the feasibility and rationality of the proposed method was verified by the practical engineering. And reached some signifecative conclusions, these can provide reference for the design and construction of such supporting system.

The bracing systems of pile and oblique bracing have obvious advantages in big and deep excavation. Because the study about the removal of oblique bracing is rare, the use of this system is limited. This author would study the transfer of internal forces and deformation issues in the process of the exchanging support through an example, from the design and construction, and the result will be verified through the measurement. The study has showed that the removal of such bracing shall tack the coordinating role of space in account, and use the collaborative computing method to remove the diagonal braces in several subregion and sections. And reached some interesting conclusions, these can provide reference for this design and construction.

Based on the LuGre friction model, the nonlinear dynamic characteristic of a sucker-rod pumping system of deviated well is simulated. Firstly, the LuGre friction model is introduced, and the values of its six model parameters, which satisfy the engineering’s needs, are obtained according to handbook and computation. Then, the vibration of the rod of sucker-rod pumping system is regarded as an axial vibration of multi-segment flexible rod. The loads analysis of rod element is accomplished by means of the finite element method, and recurrence formulas of load and elastic deformation are derived through the finite difference method. The boundary and initial conditions of the load and deformation are evaluated. In the end, a numerical example is given, where a comparison between the elastic deformation of pumping piston obtained based on LuGre friction model and that obtained based on classical Coulomb friction model is made to show that the LuGre friction model describe the friction of sucker-rod pumping system better.

We investigated the role of peripheral sympathetic neurons and the adrenal medulla in the cardiovascular responses to cocaine in conscious, unrestrained Sprague-Dawley rats. Surgical adrenal demedullation (ADM) and/or chemical peripheral sympathectomy was used to eliminate one or both components of the sympathoadrenal axis. Phentolamine (5 mg/kg i.v.) was used to evaluate whether cocaine elicited epinephrine (EPI) release from the adrenal medulla. Significant EPI release by cocaine would result in “epinephrine reversal” after phentolamine pretreatment. Cocaine (2.5 mg/kg i.v.) was used in all experiments except the dose–response relationship study. In normal rats, cocaine caused a transient increase in mean blood pressure (MBP). Pretreatment with phentolamine reversed this BP response and this depressor effect was blocked by propranolol (2 mg/kg i.v.) suggesting that the pressor effect of cocaine was mediated by EPI. Chemical sympathectomy alone partially inhibited the pressor effect of cocaine, but pretreatment with phentolamine still reversed the residual action of cocaine on MBP at this time. Two weeks after ADM, the effect of cocaine on MBP was not significantly different from that of the sham-operated rats. However, pretreatment with phentolamine inhibited but did not reverse the effect of cocaine on MBP at that time. In rats with both ADM and chemical sympathectomy, cocaine caused only a decrease in MBP that was not blocked by propranolol or atropine methylnitrate, presumably because of its direct depressive actions. Results of this study suggest that both peripheral sympathetic neurons and the adrenal medulla play important roles in the cardiovascular actions of cocaine.

The objective of this work was to evaluate the effect of phloretin on growth performance, serum biochemical parameters, antioxidant profile, glutathione (GSH)-related enzymes, nuclear factor erythroid 2–related 2 (Nrf2) and heat shock protein 70 (HSP70) in heat-stressed broilers. A total of 240, 22-day-old Arbor Acres broilers were divided into 4 groups. The control group was housed at 23.0 ± 0.61°C and fed with basal diet, while the 3 heat-stressed groups (A, B, and C groups) were housed at 30.5 ± 0.69°C and fed with basal diet containing 0, 100, and 200 mg/kg phloretin, respectively. Serum was taken form 42-day-old broilers. Results showed that heat stress decreased (P <0.05) the final body weight (FBW), body weight gain (BWG), feed intake (FI), serum total protein (TP), triglyceride (TG), triiodothyronine (T3), thyroxine (T4), GSH, catalase (CAT), and total antioxidant capacity (T-AOC) levels, but increased (P <0.05) the feed-to-gain ratio (FGR) and serum malondialdehyde (MDA) levels in broilers compared with that in the control group. Among the heat-stressed groups, supplementary 200 mg/kg phloretin increased (P <0.05) the FBW, BWG, FI, serum TP, TG, T4, GSH, CAT, and T-AOC levels, and decreased (P <0.05) the FGR and serum MDA in broilers. There were significant decreases (P <0.05) in the glutathione peroxidase (GSH-Px), γ-glutamylcysteine synthetase (γ-GCS), and Nrf2, but significant increases (P <0.05) in the HSP70 of the broiler serum after heat stress treatment. Among the heat-stressed groups, supplementary 200 mg/kg phloretin increased (P <0.05) the GSH-Px, γ-GCS, and Nrf2 levels, but decreased (P <0.05) the serum HSP70 level in the heat-stressed broilers. Under high temperature condition, FBW, BWG, FI, FGR, serum TP, TG, T4, MDA, GSH, CAT, T-AOC, GSH-Px, γ-GCS, Nrf2 and HSP70 were linearly affected by inclusion of phloretin. These results indicated that phloretin may improve growth performance, serum parameters, and antioxidant profiles through regulated GSH-related enzymes, Nrf2 and HSP70 in heat-stressed broilers.