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This study explores the stability of Al–Si–Ca–Mg-Sc melt foams and investigates the melt foam filling process and the dynamic evolution of pore structures in the fabrication of foam aluminum profiles using the melt transfer foaming technique. The results show that Al–Si–Ca–Mg-Sc melt foam maintains high porosity and a stable pore structure even after 30 min of foaming, without any signs of boundary rupture or destabilization. This stability is attributed to the increased viscosity from finely dispersed second-phase particles, which hinder the growth, coalescence, and drainage of the melt foam. Regarding melt foam filling, enhanced filling capability is achieved by elevating the foaming temperature, extending the foaming time, and increasing the TiH2 addition. The melt foam exhibits a smooth flow from the lower part of the mold to the corners, completing the filling process with well-defined edges in the profile. During lateral movement for filling, a gradual increase in porosity, a decrease in pore number, and a slow enlargement of pore size and standard deviation along the lateral (x-axis) are observed. This is due to the slower liquid phase flow compared to the gas phase, resulting in bubble coalescence. After filling is complete, this phenomenon improves, contributing to a slow and stable evolution of the pore structure.Under optimized conditions of 1.4 wt% TiH2 addition at 600°Cfor 9 min of foaming with Al–Si–Ca–Mg-Sc alloy melting, we successfully fabricated foam aluminum profiles with complete filling, a porosity of 81.5%, an average pore size of 2–3 mm, and a uniform pore structure.

The current study presents the creation of a straightforward and sensitive sensor based on ZnO/Co3O4 nanocomposite modified screen-printed electrode (ZnO/Co3O4NC/SPE) for levodopa determination. At ZnO/Co3O4NC/SPE, an oxidative peak for levodopa solution in pH 6.0 phosphate buffer solution (PBS) were seen that were both more resolved and more enhanced. Levodopa was measured using differential pulse voltammetry (DPV), which showed an excellent linear range (0.001–800.0 μM) and detection limit (0.81 nM). The presence of interference did not affect the electrochemical response of levodopa at ZnO/Co3O4NC/SPE, demonstrating high selectivity. Levodopa in a real samples have been successfully detected using the manufactured sensor.

Portable measurement of ammonia nitrogen in water is of great significance for water quality monitoring. It’s beneficial to reduce biological diseases and promote aquatic product safety. Traditional methods such as Nessler’s reagent method suffer from complex operation, time delays and toxic residues. To realize simple and pollution-free detection, this paper develops a low-cost portable device for ammonia nitrogen detection. A test paper was proposed to cooperate the device and offer a chromogenic reaction. The portable device reduces the impact of any ambient light, simplifies the operation, and provides human–computer interaction. The result obtained for the detection range of 0.4–10 mg/L (R2 are 0.990 2 and 0.989 3 for the rang of 0.4–4.5 and 4.5–10 mg/L, respectively) with the detection limit of 0.36 mg/L, and the average recovery of aquaculture water is 100.98–137.75%. The results show that the portable device can provide a great potential for on-site detection ammonia nitrogen concentration.

In this paper, an irreversible Carnot heat engine cycle model for space power plants is built by using finite time thermodynamics. A radiator panel is considered between low temperature heat sink and space environment, expressions for power output and thermal efficiency of the plant are derived. Influences of internal irreversibility effect and thermal leakage loss on the optimal power output performance are analyzed when thermal conductivity of hot- and cold-sides heat exchangers are given. For the fixed total area of three heat exchangers the double-maximum power output and double-maximum thermal efficiency are obtained further by optimizing area distributions of hot- and cold- side heat exchangers and radiator, and by optimizing temperature of low-temperature heat sink. Influences of internal irreversibility effect and thermal leakage loss on the optimal performances are investigated. The results show that when taking power output as optimization objective, if considering thermal leakage and irreversibility effect, internal irreversibility effect increases from 1.1 to 1.3, double maximum power output decreases from 216.38 kW to 139.85 kW and decreases by 35.37%, the optimal the temperature the low-temperature heat sink decreases from 556Kto 501.1Kand decreases by 9.87%, and the optimal area allocations of hot- and cold-side heat exchangers decrease from 0.213 to 0.182 and decreases by 14.55%, from 0.213 to 0.207 and decreases by 2.82%, respectively, and that of radiator increases from 0.563 to 0.611 (an increase of 8.35%). Such temperature and area distribution condition ensure the future design of plant conversion system that aligns better performances and compactness.

Grouted sleeve connectors have been widely used in vertical connections of prefabricated reinforced concrete structures. However, the quality of grouted sleeve connections are likely affected by adverse factors during winter construction such as grouting operation error, adverse environmental change, and management negligence. Some defects in winter construction are difficult to check including insufficient strength of grouting material, insufficient anchorage length of connecting reinforcement bars and adverse impact of low-temperature grouting. Although research has been carried out on the connection performance of grouted sleeves with defects, few are on the comprehensive evaluation of the connection performance of grouted sleeves with different defects caused in winter construction. In this paper, 25 groups (75 sleeves) of semi-grouted sleeve connectors with various defects are designed and manufactured. The effects of insufficient anchorage (i.e. insufficient length of reinforcement bar extending into the sleeve), insufficient strength of grouting materials and low-temperature grouting on the tensile properties of semi-grouted sleeve connectors are experimentally studied. On the basis of the test, finite element analysis is performed on extended defect conditions to comprehensively evaluate the safety control indicators. This research provides reference for the safety evaluation of grouted sleeve connections for prefabricated structures.

The nano-Ni-Al2O3/A356 nanocomposites prepared with nickel-plating, stir casting, and equal channel angle semi-solid extrusion (ECASE). The microstructure, tensile property, and fracture morphology of the fabricated nanocomposites have been investigated. The microstructure observation showed the nickel-plating could stimulate nucleation and break nanoparticle aggregation, resulting the matrix grains in a smaller size (63 μm) and the nanoparticles more uniform located on the grain boundary. The ECASE could further refine the grains size (23 μm) and improve the nanoparticle dispersion. Although 5 passes refine the grains to 16 μm, it would cause the particles to re-agglomerate, due to the nanoparticles exist in the semi-solid liquid phase for a long time. The fabricated nanocomposites exhibited an enhancement in both strength and ductility, about 1.2–2.5 times higher than those of the corresponding aluminum matrix composites. Due to the Orowan strengthening and fine grain strengthening, i.e., increased the number of grain boundaries and improved the resistance of particles to cooperative grain deformation. Meanwhile, the ECASE eliminated the intergranular defects and improved the grain boundary bonding. The enhanced mechanical properties of the nanocomposites were attributed to the grain boundary control increased by the nickel-plating and ECASE. The grain boundary control, such as increasing the grain boundary number, improving the particle-matrix adhesion and particle dispersion, can be applied to the development of high mechanical properties aluminum matrix composites.

AlCa75 with equal Ca content was used to replace pure Ca for the preparation of AlSi12 foam in a stable pore structure after foaming for 20 min. The stability mechanism was studied based on the comparison between the macroscopic pore structure evolution and the second phase composition of AlCa75 and pure Ca aluminum foam. It was found that the porosity and average pore size of the AlSi12 foam with AlCa75 were stable without any abnormal large pores, and the foaming stage was prominent. The stability of AlSi12 foam with pure Ca is inferior. After 20 min of foaming, the foam bursts in the center. Combined with the microscopic characteristic analysis, it could see that the second phase produced by AlCa75 is mainly Al2Si2Ca, which can be uniformly dispersed in the matrix. The addition of pure Ca reduces the amount of the second phase and the main phase Al4Ca is easy to agglomerate. The stability mechanism shows that the Al2Si2Ca second phase, formed by AlCa75, demonstrates a better stabilizing effect in different foaming stages. Due to the premature agglomeration caused by Al4Ca and the low content of the second phase, the AlSi12 foam with pure Ca is challenging to long-term stability.

Objective: To observe the effect of Wuweizi syrup on brain aging mice model induced by d-galactose in mice. Methods: 72 mice were randomly divided into blank group, model group, naokangling group and low, middle and high dose Wuweizi syrup group. After 3 days of adaptive feeding, except for the blank group, the rest mice were subcutaneously (sc) injected with d-galactose 1.25 g/kg at neck back to replicate the aging model. Sc injection was given for 40 consecutive days, and corresponding drugs were given by gavage on the 11th day of modeling. On the 39th day, the dark experiment was carried out to measure the learning ability of mice. After the last administration for 2 h, brain, liver, thymus and spleen were taken and weighed to calculate the organ index. Blood was taken and CAT, GSH and SOD levels in whole blood were determined. Some brain and liver tissues were taken to prepare homogenates, and MDA levels in tissue homogenates and plasma were measured. Brain, liver, thymus and spleen were stained with HE, and pathological sections were made for observation under light microscope. Results: Compared with the blank group, in the model group, the incubation period of mice was significantly reduced and the number of shuttle back and forth was significantly increased (P

Abstract Microbialites, often considered as a signal of extreme marine environment, are common in the Lower Triassic strata of South China where they flourished in the aftermath of the end-Permian mass extinction. Early Triassic microbialite facies are known to vary palaeogeographically, perhaps due to differing climates, ocean chemistry, and water depths. This paper provides the first record of a brief, but spectacular development of microbialites in the aftermath of the end-Permian mass extinction at Panjiazhuang section, Changxing Region of Zhejiang Province (eastern South China). Here, the Upper Permian Changxing Formation comprises typical shallow platform facies rich in calcareous algae and foraminifera, the development of which was terminated by the major end-Permian regression. A 3.4-m-thick microbialite began to form at the onset of the transgression in the earliest Triassic. The microbialite at Panjiazhuang section is composed of thrombolite that contains abundant calcified cyanobacteria, small gastropods, microconchid tubes and ostracods, representing a low-diversity shallow marine community in the aftermath of the end-Permian crisis. The microbialites are succeeded by thin-bedded micrites bearing thin-shelled bivalves, which record a rapid sea-level rise in the Early Triassic. Abundant populations of small pyrite framboids are observed in the upper part of the microbialites and the overlying thin-bedded micrites, suggesting that dysoxic water conditions developed at that time. The appearance of microbialites near the Permian–Triassic boundary (PTB) at Panjiazhuang section was the result of peculiar marine conditions following the end-Permian regression, whilst their disappearance was due to the increasing water depth and the development of dysoxia.

Summary: Animals require robust yet flexible programs to support locomotion. Here we report a pathway that connects the D1-like dopamine receptor DOP-1 with a sleep mechanism to modulate swimming in C. elegans. We show that DOP-1 plays a negative role in sustaining swimming behavior. By contrast, a pathway through the D2-like dopamine receptor DOP-3 negatively regulates the initiation of swimming, but its impact fades quickly over a few minutes. We find that DOP-1 and the GPCR kinase (G-protein-coupled receptor kinase-2) function in the sleep interneuron RIS, where DOP-1 modulates the secretion of a sleep neuropeptide FLP-11. We further show that DOP-1 and FLP-11 act in the same pathway to modulate swimming. Together, these results delineate a functional connection between a dopamine receptor and a sleep program to regulate swimming in C. elegans. The temporal transition between DOP-3 and DOP-1 pathways highlights the dynamic nature of neuromodulation for rhythmic movements that persist over time.

A geological event that happened at the end of the Middle Permian resulted in different levels of erosion in a shallow-water platform of South China, which led to diverse geological records in different sections. The Lianziya section in western Hubei Province of South China has a well-exposed stratigraphic sequence of the late Middle Permian rocks with abundant fossils and sedimentary facies types, providing new evidences for understanding the evolution of marine biota and environment in the late Middle Permian. Our study shows that four fossil communities can be recognized with the change of sedimentary facies in the late Middle Permian: Foraminiferal–algal community, phylloid algal community, bryozoan community and Ungdarella community. The foraminiferal–algal community is dominated by fusulinids and calcareous algae, but was soon replaced by the phylloid algal community. With an increase of terrestrial input, the phylloid algal community was again replaced by the bryozoan community. Near the end of the Middle Permian, with a decrease of terrestrial input, the bryozoan fossil community disappeared while the Ungdarella community became dominant. A 10 cm-thick weathered crust occurred at the top of the Middle Permian limestone, marking a large amplitude fall in sea-level and the beginning of a terrestrial erosion stage. The sedimentary facies and fossil community changes in the Lianziya section indicates that the Middle Permian crisis was a gradual process while the sea-level fall mainly occurred in the latest Middle Permian.

This paper aims to study the effects of different proportion of astragaloside and curcumin on STZ induced Diabetes Mellitus (DM) model of mice, and to select a better proportion of active components. Its ultimate purpose is to lay a basis for the follow-up research on astragaloside-curcumin capsule. Increase-decrease baseline geometric proportion design method and comprehensive performance evaluation utilised to study the effect of different proportion of astragaloside and curcumin on DM mice models, which have an intravenous tail injection of STZ. The proportions of the two components are 10:0, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 0:10 respectively. And we will screen out the optimal composition. Blood glycated serum protein (GSP), hepatic glycogen and insulin tested to observe pathological changes in the pancreas. The mice DM model was copied successfully. Compared with the model group, groups treated with the metformin and with different proportions of astragaloside and curcumin help lower the blood glucose levels and GSP levels, increase glycogen stores of model mice by different degrees, and avoid pathological changes of pancreas in the model mice. The ratio of 3:7 was selected as the optimal one, based on the comprehensive performance evaluation method, followed by the ratio of 4:6. The optimal proportion of DM models is 3:7, followed by 4:6. The ratio of total astragaloside and curcumin can lower blood glucose levels, GSP levels, promote the formation of glycogen, and improve the pathological changes of pancreas in the model mice. Keywords: Astragaloside, Curcumin, Baseline geometric proportion design method, STZ

Objective: In this report, the effects of cynomorium flavonoids on mouse model of perimenopausal depression were investigated. Method: 60 ovariectomized female mice were randomly divided into 6 groups evenly: high, medium and low doses of cynomorium flavonoids groups (400 mg kg−1, 200 mg kg−1, 100 mg kg−1), Gengnian’an capsule group (675 mg kg−1), soy isoflavones soft capsule group (250 mg kg−1), and model group. Give the corresponding drug five days after surgery once a day, consecutive thirty days. The model group and control group were given the water of same volume. The model related groups were applied with different stress for consecutive eighteen days. Kill the mice and remove the thymus, spleen, uterus and one hand of brain when it is 2 h after the last administration in mice of each group. Observe the histological changes of each group under light microscope. Results: By observing the pathological section, compared with model group, the pathological changes of the uterus and hypothalamus of mice were significantly improved. The thymic cortex markedly thickened, volume of splenic nodule also significantly increased, and the number of lymphocytes significantly increased (p

Cantharidin (CTD) is a traditional Chinese medicine that shows an anticancer effects in multiple types of cancer cells. However, the mechanism of CTD anti-cancer function in gastric cancer (GC) is still unclear. The aim of the present study was to investigate the underlying mechanism that CTD inhibits proliferation and migration through suppression of the PI3K/Akt signaling. CTD induced GC cell apoptosis and inhibited metastasis measured by CCK8 assays as well as wound healing assays and transwell assays. Mechanistic investigations suggested that CTD modulated the PI3K/Akt signaling via western-blot and quantitative q-PCR. In addition, we identified and confirmed CCAT1 as a novel direct target of CTD inhibited PI3K/AKt signaling expression. In conclusion, our results provide new point into the critical role of CTD in suppressing PI3K/Akt signaling via down-regulation of CCAT1, resulting in suppression GC cell growth and migration/invasion., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The dysregulation of long non-coding RNA (lncRNA) has increasingly been linked to human gastric cancer (GC). However, the LINC01606 expression level and clinical values, and its role in the molecular mechanism underlying GC remain largely unknown. In our research, we found that LINC010606 was elevated aberrantly and correlated with metastasis and invasion in GC patients. Moreover, we found that LINC01606 expression level was associated with Wnt/β-catenin signaling. In addition, subsequent functional experiments showed that JW74, a specific Wnt/β-catenin signaling inhibitor, inhibited the transcription of LINC01606 and suppressed migration and invasion in GC cell lines. We also revealed that LINC01606 might be associated with miR-423-5p to regulate the level to which the Wnt/β-catenin signaling pathway is activated. In summary, the findings of this study, based on competing endogenous RNA (ceRNA) theory, combine new data on the interaction between miR-423-5p and Wnt3a and introduce LINC01606 as a new focus for research, thus providing new insight into possible molecular-level approaches to preventing the migration and invasion of GC., (Copyright © 2018. Published by Elsevier Ltd.)

Most of current absorbents are difficult to hold favorable stability and functionality simultaneously when used in condition of high acidity and strong radiation existing in nuclear industry. Herein, a new graphene-synergized 2D covalent organic framework (GS-COF) was obtained via an in-situ loading of a covalent organic framework (TDCOF) on graphene sheets based on a mutual promotion strategy proposed in this work. The corresponding oximation products, o-GS-COF, and also o-TDCOF as a reference object, were respectively prepared subsequently. The results of experiments confirmed that o-GS-COF possesses better acid and irradiation stability than that of o-TDCOF. Adsorption experiments showed that the adsorption capacity of o-GS-COF for uranium is 144.2 mg g -1 , higher than that of GO (92.5 mg g -1 ) and o-TDCOF (105.0 mg g -1 ), and the maximum adsorption capacity reaches 220.1 mg g -1 . In the multi-ions system, o-GS-COF also displayed good selective adsorption property for uranium with SF U/M 35-100 for 5 coexisting divalent metal ions and 14-18 for 5 coexisting trivalent lanthanide ions. The proposed strategy successfully achieved the synergistic improvement of both stability and functionality for the desired adsorbing materials and is of considerable practical utility in the field of design and preparation of reliable high-performance absorbents., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Tissue engineering is aiming to build an artificial environment or biological scaffold material that imitates the living environment of cells in the body. In this work, carboxymethyl cellulose sulfates were prepared by reacting carboxymethyl cellulose with N(SO3Na)3 which was synthesized by sodium bisulfite and sodium nitrite in aqueous solution. The reaction conditions affected the degree of substitution (DS) were measured by the barium sulfate nephelometry method. And the anticoagulant activity of carboxymethyl cellulose sulfates with different DS, concentration and molecular weights were investigated by the activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT). In addition, the effect of carboxymethyl cellulose sulfates on wound healing had been evaluated by the rate of wound healing and the histological examinations. The results indicated that the introduction of sulfate groups into the carboxymethyl cellulose sulfates improved its anticoagulant activity, and the wound dressings treated with carboxymethyl cellulose sulfates obviously promoted wound healing., (Copyright © 2014 Elsevier B.V. All rights reserved.)