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It is recognized that the introduction of ceramic particles has been used to produce composite coating in laser cladding to enhance the hardness of Ti6Al4V titanium alloy. In this study, (nano WC + micron TiC)/Ti6Al4V coatings with different composite ceramic contents were manufactured on Ti6Al4V substrate by laser cladding. The effects of the multi-scale composite ceramics on the macroscopic morphology, microstructure, and microhardness of coatings were comprehensively analyzed. The results showed that the coatings were mainly composed of α-Ti and (Ti, W)C1 − x. The partial melting of TiC and WC ceramics resulted in the dissolution of C atoms in the matrix of the coatings, thereby strengthening the coatings through solid solution formation. Meanwhile, the growth of (Ti, W)C1 − x was inhibited, owing to the pinning force exerted by nano WC at the grain boundaries. When the content of nano WC was 1.5 wt%, (Ti, W)C1 − x in the coating exhibited micron-scale dendritic and submicron granular structures. The average size of the (Ti, W)C1 − x was approximately 0.31 µm. Moreover, the optimal microhardness of the coating reached 459.99 HV, representing a 35.99% increase compared to the microhardness of the Ti6Al4V substrate. The enhancement in microhardness was primarily attributed to three key strengthening mechanisms: fine-grain strengthening, Orowan strengthening, and solid-solution strengthening, which were effects induced by the ceramic particles. [ABSTRACT FROM AUTHOR]

In order to improve the mechanical property prediction accuracy of AZ80 magnesium alloy, sparrow search algorithm (SSA) is optimized by the tent chaotic mapping (TCM) algorithm, yielding TCMSSA, and TCMSSA is employed to improve extreme learning machine (ELM) model for obtaining TCMSSA-ELM model. TCMSSA-ELM model, along with the traditional ELM model, are both utilized to predict the stress of AZ80 magnesium alloy in a temperature range of 523 K to 673 K and a strain rate range of 0.001s− 1 to 1s− 1. Comparative analysis is conducted to evaluate the performance differences between the two models. The results indicate that compared with ELM model, the predicted values of TCMSSA-ELM model are closer to the experimental data and the ideal 45° line, proving the higher prediction accuracy of TCMSSA-ELM model. In addition, through algorithmic improvements, the maximum reduction of MAPE is 85.422% and the maximum determination coefficient reaches 0.99956, implying that TCMSSA greatly improves the prediction precision of ELM model. The related results offer a new optimization strategy and model to predict the mechanical property of AZ80 magnesium alloy in each molding stage, and provide a technical reference for applying intelligent algorithms to alloy design. [ABSTRACT FROM AUTHOR]

A neural network accelerated optimization method for FPGA hardware platform is proposed. The method realizes the optimized deployment of neural network algorithms for FPGA hardware platforms from three aspects: computational speed, flexible transplantation, and development methods. Replacing multiplication based on Mitchell algorithm not only breaks through the speed bottleneck of neural network hardware acceleration caused by long multiplication period, but also makes the parallel acceleration of neural network algorithm get rid of the dependence on the number of hardware multipliers in FPGA, which can give full play to the advantages of FPGA parallel acceleration and maximize the computing speed. Based on the configurable strategy of neural network parameters, the number of network layers and nodes within layers can be adjusted according to different logical resource of FPGA, improving the flexibility of neural network transplantation. The adoption of HLS development method overcomes the shortcomings of RTL method in designing complex neural network algorithms, such as high difficulty in development and long development cycle. Using the Cyclone V SE 5CSEBA6U23I7 FPGA as the target device, a parameter configurable BP neural network was designed based on the proposed method. The usage of logical resources such as ALUT, Flip-Flop, RAM, and DSP were 39.6%, 40%, 56.9%, and 18.3% of the pre-optimized ones, respectively. The feasibility of the proposed method was verified using MNIST digital recognition and facial recognition as application scenarios. Compare to pre-optimization, the test time of MNIST number recognition is reduced to 67.58%, and the success rate was lost 0.195%. The test time for facial recognition applications was reduced to 69.571%, and the success rate of combining LDA algorithm was lost within 4%. [ABSTRACT FROM AUTHOR]

Language difficulties exert profound negative effects on the cognitive and social development of autistic children. Pivotal Response Treatment (PRT) is a promising intervention for improving social communication in autistic children, but there is a lack of a comprehensive examination of language functions. This study aimed to investigate the effectiveness of PRT in promoting the primary language functions (requesting, labeling, repeating, responding) defined by (Skinner, B. F. (1957). Verbal behavior. Martino Publishing.) theory of verbal behavior in autistic children. Thirty autistic children were randomly divided into the PRT group (Mage = 6.20, SDage = 1.21) and control group (Mage = 6.07, SDage = 1.49). The PRT group were provided with an 8-week training of the PRT motivation component in addition to treatment as usual (TAU) in their schools, whereas the control group only received TAU. Parents of the PRT group were also trained to practice the PRT motivation procedures at home. The PRT group demonstrated greater improvements in all four measured language functions compared to the control group. The improvement in language functions in the PRT group was generalized and maintained at the follow-up assessment. In addition, the PRT intervention enhanced untargeted social and communicative functioning, cognition, motor skills, imitation, and adaptive behaviors in the autistic children. In conclusion, language intervention using the motivation component of PRT is effective in promoting language functions as well as widespread untargeted cognitive and social functions in autistic children. [ABSTRACT FROM AUTHOR]

A series of red-luminescence bismuthate phosphors of double perovskite BaBiNaTeO6 doped with trivalent europium (Eu3+) were prepared by the solid-state diffusion method. The crystal structure and phase purity of the phosphors were analyzed. The photoluminescence (PL) properties of BaBiNaTeO6:Eu3+ were studied in detail. Upon blue light (466 nm) excitation, the powders showed brilliant red light at around 619 nm, and it was attributed to the electric dipole (ED) 5D0 → 7F2 transition of Eu3+. The optimal dopant concentration (x) of the as-prepared phosphor was x = 0.60 mol and the concentration quenching mechanism was evaluated as the electric quadrupole–quadrupole interaction. The BaBiNaTeO6:Eu3+ exhibited good thermal stability and the corresponding activation energy (Ea) was obtained to be 0.27 eV. The chromaticity points of phosphors were near the edge of the red region of the Commission Internationale De L’Eclairage (CIE) 1931 chromaticity diagram. As-prepared white LED based on the GaN blue chip exhibited relatively low correlated color temperature (CCT) of 5042.5 K and high color rendering index (CRI) of 91.6. All characterizations suggest that these double perovskite BaBiNaTeO6:Eu3+ red-emitting phosphors have promising applications in illumination and display field based on blue LEDs. [ABSTRACT FROM AUTHOR]

Due to the mirror image symmetry of laser mirror welding heat sources, the post-weld deformation is observably lower than that of conventional welding methods. However, the mechanism of gravitational effects on the coupled keyhole molten pool at different welding positions is still unclear, which results in the tough control of welding defects, hindering the application of laser mirror welding in precision manufacturing of aerospace structural parts. In this study, the gravity effects on keyhole behaviors in laser mirror welding of 2219 aluminum alloy were investigated by establishing a computational fluid dynamics (CFD) model. The keyhole morphology, coupling characteristics, and its dynamic evolution as well as force conditions were analyzed at length by employing the calibrated model. The results showed that gravity prominently affects the fluid velocity in the molten pool, which determines the keyhole characteristics. The keyhole surface flow, which enlarges the keyhole diameter, is impeded by gravity, resulting in weak keyhole coupling. The keyhole area on the weld cross-section before coupling is less than 2 mm2 and is negatively correlated with the gravitational component on this section. The keyhole area after coupling is tightly relevant to the keyhole diameter. The increase or decrease in the keyhole diameter is contingent on the resultant direction of gravity, fluid pressure, and vapor recoil pressure. Additionally, the keyhole coupling and dynamic behaviors in the welding direction are primarily affected by the surface tension gradient, while slightly affected by gravity. [ABSTRACT FROM AUTHOR]

Key message: VyPUB21 plays a key role during the defense against powdery mildew in grapes. Ubiquitin-ligating enzyme (E3), a type of protein widely found in plants, plays a key role in their resistance to disease. Yet how E3 participates in the disease-resistant response of Chinese wild grapevine (Vitis yeshanensis) remains unclear. Here we isolated and identified a U-box type E3 ubiquitin ligase, VyPUB21, from V. yeshanensis. This gene’s expression level rose rapidly after induction by exogenous salicylic acid (SA), jasmonic acid (JA), and ethylene (ETH) and powdery mildew. In vitro ubiquitination assay results revealed VyPUB21 could produce ubiquitination bands after co-incubation with ubiquitin, ubiquitin-activating enzyme (E1), and ubiquitin-conjugating enzyme (E2); further, mutation of the conserved amino acid site in the U-box can inhibit the ubiquitination. Transgenic VyPUB21 Arabidopsis had low susceptibility to powdery mildew, and significantly fewer conidiophores and spores on its leaves. Expression levels of disease resistance-related genes were also augmented in transgenic Arabidopsis, and its SA concentration also significantly increased. VyPUB21 interacts with VyNIMIN and targets VyNIMIN protein hydrolysis through the 26S proteasome system. Thus, the repressive effect of the NIMIN–NPR complex on the late systemic acquired resistance (SAR) gene was attenuated, resulting in enhanced resistance to powdery mildew. These results indicate that VyPUB21 encoding ubiquitin ligase U-box E3 activates the SA signaling pathway, and VyPUB21 promotes the expression of late SAR gene by degrading the important protein VyNIMIN of SA signaling pathway, thus enhancing grape resistance to powdery mildew. [ABSTRACT FROM AUTHOR]

Background: The mode of delivery for twins born before 32 weeks of gestation remains controversial. Our purpose is to conduct a meta-analysis of twin pregnancies less than 32 weeks or twin weight less than 1500 g, so as to find a suitable delivery mode. Methods: We searched PubMed database, Cochrane Library database, and EMBASE database through December 2022. This protocol was registered with PROSPERO (CRD42023386946) prior to initiation. Studies that compared vaginal delivery to cesarean section for newborns less than 32 weeks of gestation or birthweight under 1500 g were included. The primary result was neonatal mortality rate. Secondary result was neonatal morbidity. The quality of literatures included in the research was evaluated in accordance with Newcastle–Ottawa Scale (NOS) literature quality evaluation scale. We use odds ratio (OR) as the effect index for binary variables. Point estimates and 95% confidence intervals (95% CI) were calculated. P < 0. 05 indicated statistically significant difference. Results: Our search generated 5310 articles, and a total of 8 articles comprising a total of 14,703 newborns were included in the analysis. The odds ratios of neonatal mortality rate were for twins delivered by vaginal delivery compared to cesarean section were 0.84 (95% CI 0.57–1.24, P = 0.38). The 5-min Apgar score < 7 (95% CI 0.44–1.75, P = 0.72), necrotizing enterocolitis (95% CI 0.81–1.19, P = 0.82), intraventricular hemorrhage (95% CI 0.41–1.86, P = 0.71), periventricular leukomalacia (95% CI 0.16–4.52, P = 0.84), bronchopulmonary dysplasia (95% CI 0.88–1.36, P = 0.42), and respiratory distress syndrome (95% CI 0.23–2.01, P = 0.48) were not statistically significant between the two groups. Conclusion: We have observed that vaginal delivery does not confer an increased risk of neonatal morbidity and mortality in twins born before 32 weeks of gestation. However, the current results are affected by substantial heterogeneity and confounding factors. We still need high-quality randomized-controlled studies require to address this important question. [ABSTRACT FROM AUTHOR]

Uniform grain morphology and low porosity are the key to obtain better mechanical properties of 2319 aluminum alloy fabricated by wire arc additive manufacture. In this study, the influence of heat flow on the grain morphology and porosity was investigated by experimental and simulation methods. The solidification theory was used to illustrate the columnar-to-equiaxed transition phenomenon and the variation in the volume fractions of different grains. The results show that the deposition layer was composed of fine equiaxed grains in the inter-layer zone, columnar and equiaxed grains in the lower and upper parts the of inner-layer zone, respectively. Furthermore, the volume fractions of the equiaxed and columnar grains were varied by adjusting wire feed rates (WFR). With the higher WFR, the volume fraction of columnar grains decreases, while the porosity and tensile strength first increase and then decrease. The best mechanical properties could be achieved when the WFR was 5.5 m/min, with a tensile strength of 274 MPa and an elongation of 12.5%. [ABSTRACT FROM AUTHOR]

Laser melting deposition (LMD) is an advanced repairing and remanufacturing technology that involves complex thermodynamic and kinetic characteristics in a molten pool. A thorough understanding of the thermal-fluid dynamic behavior of molten metal is crucial for investigating the distribution of reinforced particles and the characterization of solidification. This study proposes a three-dimensional transient thermal-fluid coupling model for describing thermal-fluid dynamic behavior and particle migration behavior within a molten pool during LMD. The simulated morphology of the deposition layer and temperature agree well with the experiments. The simulation results indicate that Marangoni convection induced by temperature gradient dominates the convection mode. The fluid velocity distribution along the scanning direction of the molten metal is showing M shape. Meanwhile, the dimension of molten pool increases slightly, and the Marangoni convection becomes more vigorous with higher heat input. The Marangoni motion tends to drive the TiC particle migration from the center to both lateral sides, resulting in a more uniformly distributed of TiC particle in deposition layer. Furthermore, the solidification parameters at solid–liquid interface are calculated, which used to assess the solidification microstructure in deposition layer. [ABSTRACT FROM AUTHOR]

Aspartame (ASP) as an important sugar substitute is widely used in pharmaceutical and food processing. Here, we compared the effects of ASP and sucrose on mice pancreatic islet cells in vivo and observed that ASP with the condition of high concentration and long-term exposure (HASP) could cause insulin secretion (500 mg/kg for 1 month). Next, we conducted iTRAQ mass spectrometry to profile the global phosphoproteome and found that phosphorylation of zipper-interacting protein kinase (ZIPK) in murine pancreatic islet tissues were induced at Thr197, Thr242, Thr282, and Ser328 by high-sucrose (HS) treatment, but only induced at Thr197 and Ser328 by HASP treatment. Simultaneously, phosphorylation of STAT3 could be induced at Tyr705 and Ser727 by HS but not by HASP. Furthermore, presence of activated STAT3 accompanied with autophagy was observed in HS treatment. In turn, the inactivation of STAT3 as well as enhanced expression of caspase 3 was observed in HASP treatment. We generated Thr242APro and Thr282Pro on ZIPK using CRISPR-Cas9 in β-TC3 cells and found the weakened interaction with STAT3 as well as the reduced phosphorylation of STAT3 even under HS stimulation. Finally, we observed that ankyrin repeat domain containing 11 (ANKRD11) could interact with ZIPK and play an inhibitory role in the phosphorylation of Thr242APro and Thr282Pro of ZIPK. However, HASP can induce the retention of ANKRD11 in the cytoplasm by phenylpyruvic acid (the metabolite of ASP). Taken together, this study determined that ASP with high concentration and long-term exposure could lead to caspase-dependent apoptosis of pancreatic islet cells through ANKRD11/ZIPK/STAT3 inhibition. Our results give evidence of adverse effects of aspartame on islet cells in some extreme conditions, which might help people to reconsider the biosafety of non-nutritive sweeteners. [ABSTRACT FROM AUTHOR]

In the Majiagou landslide of the Three Gorges Reservoir Area, there appears a wide crack between the anti-pile and sliding body behind the piles, which can hardly be clarified by the sliding force of the sliding body. Therefore, the deformation mechanism of anti-piles in the Majiagou landslide was studied to explain how the crack appears between the anti-pile and sliding body behind the piles from perspectives of embedded rock degradation and declining water level. The mechanical degradation of the embedded rock was studied experimentally with triaxial compression and Brazilian splitting tests at first. Then, the embedded rock degradation and declining water level were introduced into the FLAC3D model, where the deformation mechanism of anti-piles and soils behind the anti-piles were studied. The results show that the rock resistances in front of anti-piles gradually decrease and the embedding effect of anti-piles gradually weakens due to the embedded rock degradation, resulting in plastic deformation in the rock and forward inclination of anti-piles. In addition, the declining water level leads to an increasing seepage force, leading to an increasing sliding deformation of the sliding body in front of the anti-piles, which weakens the front support of the anti-pile. Thus, the anti-pile displacements continually increase and exceed those of the sliding body behind the pile, and a wide crack appears between the anti-pile and sliding body behind the piles as a result. Consequently, the mechanical and deformation parameters after degradation should be employed for the reinforcement design of anti-piles in reservoir bank slopes. [ABSTRACT FROM AUTHOR]

Wire arc additive manufacturing (WAAM) has advantages such as high manufacturing flexibility and efficiency, making it feasible to fabricate large-scale aircraft components. Additive manufactured aircraft component suffers thermal processes during manufacturing and high-speed flight, affecting their microstructure, mechanical property, and lifetime. As-built microstructure and residual stress of the WAAM component and its evolution during thermal service are essential but nearly absent from the literature. This paper studies the evolution characteristic of microstructure, temperature field, stress distribution, and mechanical properties of 2319 aluminum alloy during the WAAM process and simulated high-speed flight. Results indicate that equiaxed grains and dendrite size in the top region increase slightly after thermal service, the grain distribution becomes more uniform, and the boundary between layers is far less evident than the as-built state. After thermal service, the WAAM component inherits the as-built mechanical properties. The lower wire feeding rate and the higher scanning speed can significantly reduce the maximum stress value of the WAAM component and change the stress distribution during thermal service. Tensile strength of WAAM sample increases after 1st thermal service and decreases after 10th thermal service. The existence of many dimples in the fracture indicates that the tensile fracture mode of the WAAM sample is microporous aggregation fracture. The number of dimples and particles in the fracture reduces significantly after the 10th thermal service, resulting in a decrease in fracture plasticity and tensile strength of the WAAM component. [ABSTRACT FROM AUTHOR]

Wire arc additive manufacturing (WAAM) is widely studied due to its high deposition rate. However, WAAM samples have poor forming quality compared with other additive manufacturing technologies. The quality of sample formation is directly related to the time required for subsequent mechanical processing. Hence, cycle time can further be reduced by controlling the forming quality. Additionally, better forming quality results in less material wastage. Therefore, the forming quality of samples has always been the focus of WAAM. In this paper, the droplet transfer process of the WAAM is shot with a high-speed camera. This article attempts to explain the WAAM forming process from the perspective of droplet transfer and evaluate the influence mechanism of droplet transfer on the side surface forming quality. High-speed photography is used to extract the molten pool size and droplet transfer frequency. The study also explored the variation of these factors with wire feed speed and number of layers. A two-dimensional droplet transfer model is established based on the results of high-speed photography to study the droplet transfer process. Next, the 3D sample model is built to obtain the roughness of deposition samples. Finally, the relationship between the forming quality and droplet transfer process is studied through the fitting planes. The relationship model of wire feeding speed, molten pool length/droplet transfer frequency, and roughness is obtained. The roughness of the side surface increases with higher wire feed speeds when the wire feed speed is 5.5–6.5 m/min. However, at a wire feed speed of 7.0 m/min, the roughness of the side surface suddenly decreases. The droplet transfer motion rule is then used to explain this change in forming quality. [ABSTRACT FROM AUTHOR]

Friction stir additive manufacturing technology has emerged as an efficient solid-state process option that provides superior connectivity for lightweight structural material with equiaxed microstructures and outstanding mechanical properties. In this paper, a multilayer ring-shaped build made from 6061-T6 aluminum alloy using friction stir additive manufacturing (FSAM) was characterized. The rotating torque exerted on the friction tool by the surrounding material was measured as it moves to the middle and the end of the ring. Additionally, the correlation between the microstructure and the rotating torque was investigated. The results revealed a significant decrease in rotating torque when the stir tool returned to its original position in the additive zone, leading to a reduction in grain size within the additive zone. Underneath the bottom of the stir zone, there was an overlapping interface filled with deformed grains. Along the horizontal direction, the highest hardness existed in the base material region, while the lowest value appeared in the mixed area of the thermal–mechanical affected zone and heat-affected zone. The hardness value of the stir zone was found to be intermediate between the base material region and the mixed area of the thermal–mechanical affected zone and heat-affected zone. The highest and lowest hardness values along the tool-axial direction were observed at the top of the stir zone and the overlapping interface below it. [ABSTRACT FROM AUTHOR]

The stable recovery of gas sensors is an important indicator for evaluating their performance. Hitherto, the use of external light sources and/or an increase in the operating temperature has been effective in improving the recovery rate of gas sensors. Herein, heterojunctions were formed between the two-dimensional transition metal dichalcogenide nanosheets and zero-dimensional ZnO nanoparticles to improve the recovery rate of a NO2 sensor. Scanning electron microscopy and Raman spectroscopy suggested a successful deposition of ZnO nanoparticles onto the MoS2 and WSe2 nanosheets. The sensing response to 10 ppm NO2 gas at 100 °C indicated that the heterojunction formed by ZnO and MoS2 or WSe2 successfully improved the recovery rate of the sensor by 11.87% and 19.44%, respectively, whereas the sensitivity remained constant. The proposed approach contributes to improving the performance of gas sensors. [ABSTRACT FROM AUTHOR]

Purpose: To report a rare type of Pallister-Killian syndrome (PKS) diagnosed prenatally by the utility of non-invasive prenatal testing (NIPT). Methods: NIPT was performed in the first trimester. Conventional karyotyping and chromosomal microarray analysis (CMA) were performed on the amniotic samples in the second trimester. Copy number variation sequencing (CNV-seq) was used for the validation of fetal skin and the placental tissue after pregnancy termination. Results: NIPT results showed increased signal from chromosome 12p. Subsequent prenatal diagnostic testing by karyotype revealed 47, XY, +i (12p), and CMA displayed four copies of 12p: 12p13.33-12p11.1(173786_34835641) × 4. The CNV-seq results of the fetal skin and the fetal side of placenta showed four copies of 12p13.33-p11 and an estimated chimeric duplication of 34.08 Mb (chimerism ratio: 10%) in 12 p13.33-p11, respectively. However, no abnormality was detected by CNV-seq at the maternal side of placenta. Conclusions: Our findings suggest that a positive signal from chromosome 12p on NIPT should raise suspicion for PKS. With the wide application of NIPT, the true positive of incidental finding is expected to increase. [ABSTRACT FROM AUTHOR]

Cytochrome P450 153 A (CYP153A) is a versatile enzyme that can catalyze a wide range of oxidation reactions on various substrates. This review provides a comprehensive overview of the current state of knowledge on CYP153A, including its classification, structure, function, and potential applications in biotechnology and pharmaceuticals. The CYP153A family encompasses many enzymes with different functions on a variety of substrates. We also discuss the structural features that are responsible for the different substrate specificities. Additionally, the enzyme has been engineered to increase its catalytic activity and modifications have been made to enhance its properties further. Despite its potential, challenges and limitations associated with studying and exploiting CYP153A remain, such as low expression levels and substrate inhibition. Nonetheless, ongoing research is exploring new ways to harness the enzyme's capabilities, particularly in synthetic biology, biocatalysis, and drug discovery, making it an exciting target for future research. [ABSTRACT FROM AUTHOR]

Laser welding is a feasible process for joining the additive manufactured (AMed) parts to meet the manufacturing demand of specific large-scale components. Microstructure and property evolution as well as weldability of the laser welding of wire arc additive manufactured (WAAMed) Al-Cu alloy are investigated. Results indicate that the WAAMed Al-Cu alloy has excellent laser weldability and the joint is nearly free of defect. The width of the heat-affected-zone (HAZ) and equiaxed crystal zone (EQZ) as well as the grain size of the fusion zone (FZ) will increase with higher laser power and heat input. The joint with laser power of 3500 W has the highest tensile strength and elongation, reaching 203.48 MPa and 4.13%. The result from electron backscatter diffraction (EBSD) test indicates that the texture intensity will affect tensile properties. The tensile strength and elongation of the laser welded WAAM sample perpendicular to the deposition direction are higher than that parallel to the deposition direction. The microhardness value of HAZ is higher than that of FZ and BM due to 163 HV. The feasibility of laser welding of WAAMed samples is validated, and process parameters are found for hybrid manufacturing of large-scale components. [ABSTRACT FROM AUTHOR]

Abnormalities in subcortical brain structures may reflect higher suicide risk in mood disorders, but less is known about its associations for schizophrenia. This cross-sectional imaging study aimed to explore whether the history of suicide attempts was associated with subcortical changes among individuals with schizophrenia. We recruited 44 individuals with schizophrenia and a history of suicide attempts (SZ-SA) and 44 individuals with schizophrenia but without a history of suicide attempts (SZ-NSA) and 44 healthy controls. Linear regression showed that SZ-SA had smaller volumes of the hippocampus (Cohen's d = −0.72), the amygdala (Cohen's d = −0.69), and some nuclei of the amygdala (Cohen's d, −0.57 to −0.72) than SZ-NSA after adjusting for age, sex, illness phase, and intracranial volume. There was no difference in the volume of the subfields of the hippocampus. It suggests the history of suicide attempts is associated with subcortical volume alterations in schizophrenia. [ABSTRACT FROM AUTHOR]

Leg problems characterized by gait abnormity and bone structure destruction are associated with a high risk of fractures and continuous pain in poultry. Zinc (Zn) acts a pivotal part in normal bone homeostasis and has proven to be highly effective in alleviating leg problems. Therefore, the effects of graded concentration of Zn on bone quality were evaluated in this study. A total of 512 1-d-old male ducks were fed 4 basal diets added 30 mg/kg Zn, 60 mg/kg Zn, 90 mg/kg Zn, and 120 mg/kg Zn as Zn glycine for 35 d. Tibia Zn content, ash percentage, and breaking strength linearly increased with dietary elevated Zn level (P < 0.05). Broken-line analysis revealed that the recommended level of Zn from Zn glycine was 55.13 mg/kg and 64.48 mg/kg based on tibia ash and strength, respectively. To further confirm the role of dietary Zn glycine addition on bone characteristics, data from birds fed either 60 mg/kg Zn as Zn sulfate (ZnSO4), 30 mg/kg Zn, or 60 mg/kg Zn in the form of Zn glycine indicated that birds given 60 mg/kg Zn from Zn glycine diet exhibited higher tibia ash, strength, and trabecular volume compared to those fed the 30 mg/kg Zn diet (P < 0.05). Dietary 60 mg/kg Zn as Zn glycine addition decreased intestinal permeability, upregulated the mRNA expression of tight junction protein, and increased the abundance of Lactobacillus and Bifidobacterium, which was companied by declined the level of inflammatory cytokines in both the ileum and bone marrow. Regarding bone turnover, the diet with 60 mg/kg Zn from Zn glycine induced osteoprotegerin expression and thus decreased osteoclast number and serum bone resorption biomarker levels including serum tartrate-resistant acid phosphatase activity and C-terminal cross-linked telopeptide of type I collagen level when compared to 30 mg/kg Zn diet (P < 0.05). Except for the upregulation in runt-related transcription factor 2 transcription, the experimental treatments did not apparently change the bone formation biomarker contents in serum. Additionally, Zn glycine displayed a more efficient absorption rate, evidenced by higher serum Zn level, and thus had potentially greater a protective role in the intestine barrier and tibia mass as compared to ZnSO4. Collectively, the dietary supplementation of 60 mg/kg in the form of Zn glycine could suppress bone resorption mediated by osteoclast and consequently improve tibial quality of meat ducks, in which enhanced intestinal integrity and optimized gut microbiota might be involved. [ABSTRACT FROM AUTHOR]

Core-shell bimetallic nanocatalysts have attracted long-standing attention in heterogeneous catalysis. Tailoring both the core size and shell thickness to the dedicated geometrical and electronic properties for high catalytic reactivity is important but challenging. Here, taking Au@Pd core-shell catalysts as an example, we disclose by theory that a large size of Au core with a two monolayer of Pd shell is vital to eliminate undesired lattice contractions and ligand destabilizations for optimum benzyl alcohol adsorption. A set of Au@Pd/SiO2 catalysts with various core sizes and shell thicknesses are precisely fabricated. In the benzyl alcohol oxidation reaction, we find that the activity increases monotonically with the core size but varies nonmontonically with the shell thickness, where a record-high activity is achieved on a Au@Pd catalyst with a large core size of 6.8 nm and a shell thickness of ~2–3 monolayers. These findings highlight the conjugated dual particle size effect in bimetallic catalysis. Tailoring both the core size and shell thickness of core-shell bimetallic nanocatalysts to the dedicated geometrical and electronic properties are vital for catalytic performance optimization. Here the authors demonstrate such conjugated dual particle size effects on Au@Pd catalyzed benzyl alcohol oxidation. [ABSTRACT FROM AUTHOR]

Due to the small range of plastic deformation temperatures during hot rolling of Zircaloy-4 plates, it is important to determine the appropriate flow behaviors for plate profile control of Zircaloy-4 plates. The developed microstructures and mechanical properties of Zircaloy-4 are evaluated by metallographic observations and Gleeble-3800 thermal simulation tester. To meet the need of data with small-sample properties, the support vector regression (SVR) algorithm is adopted to predict the constitutive model of Zircaloy-4, and the improved particle swarm optimization algorithm (IPSO) is used to optimize parameters of SVR algorithm. Meanwhile, results indicate that the correlation coefficient (R2) value of zirconium alloy constitutive model is 96.805%. Based on employed algorithm, comparing with modified Arrhenius model, the results show the superiority of IPSO-SVR algorithm. This provides an important theoretical basis for FE simulation of controlling the Zircaloy-4 plate shape during hot rolling process. [ABSTRACT FROM AUTHOR]

The bottom-locking joint is widely used in the aerospace manufacturing field as an imperative connection structure. The laser welding experiment for the Ti-6Al-4V titanium alloy bottom-locking joint is carried out in the present paper. Meanwhile, porosity in the weld seam including the process porosity and metallurgical porosity is investigated. Furthermore, it is novel that the distribution, element characteristics, and formation mechanism of process porosities and metallurgical porosities in the bottom-locking joint are comprehensively analysed based on the porosity morphology, microstructure, and element analysis of the resultant bottom-locking joints. The process porosity, which mainly appeared in the weld seam centre, is formed by the combined effect of two mechanisms which closely related to the dynamic behaviour of the molten pool and the stability of the keyhole. Besides, a large number of micropores with a diameter of 2–5 µm are observed on the surface of the process porosity, whose formation is related to the evaporation of elements. Moreover, the tensile stress generated during the solidification and shrinkage of the molten metal is the main factor leading to microcracks in the micropores. The nucleation characteristics of bubbles cause metallurgical porosities to be mainly distributed at the bottom of the weld seam. [ABSTRACT FROM AUTHOR]

The development of high-performance strain sensors has attracted significant attention in the field of smart wearable devices. However, stretchable strain sensors usually suffer from a trade-off between sensitivity and sensing range. In this study, we investigate a highly sensitive and stretchable piezoresistive strain sensor composed of a hybrid film of 1D multi-walled carbon nanotube (MWCNT) and 2D graphene that forms a percolation network on Ecoflex substrate by spray coating. The mass of spray-coated MWCNT and graphene and their mass ratio are modulated to overcome the trade-off between strain sensitivity and sensing range. We experimentally found that a stable percolation network is formed by 0.18 mg of MWCNTs (coating area of 200 mm2), with a maximum gauge factor (GF) of 1,935.6 and stretchability of 814.2%. By incorporating the 0.36 mg of graphene into the MWCNT film (i.e., a mass ratio of 1:2 between MWCNT and graphene), the GF is further improved to 12,144.7 in a strain range of 650–700%. This high GF is caused by the easy separation of the graphene network under the applied strain due to its two-dimensional (2D) shape. High stretchability originates from the high aspect ratio of MWCNTs that bridges the randomly distributed graphenes, maintaining a conductive network even under sizeable tensile strain. Furthermore, a small difference in work function between MWCNT and graphene and their stable percolation network enables sensitive UV light detection even under a significant strain of 300% that cannot be achieved by sensors composed of MWCNT- or graphene-only. The hybrids of MWCNT and graphene provide an opportunity to achieve high-performance stretchable devices. [ABSTRACT FROM AUTHOR]

This correction notice is for an article titled "Loss of cold tolerance is conferred by absence of the WRKY34 promoter fragment during tomato evolution" published in Nature Communications. The correction addresses an error in Figure 4e of the original article, where the images showing yeast growth were duplicated. The error has been corrected in both the PDF and HTML versions of the article. The authors of the article are Mingyue Guo, Fengjun Yang, Lijuan Zhu, Leilei Wang, Zhichao Li, Zhenyu Qi, Vasileios Fotopoulos, Jingquan Yu, and Jie Zhou. [Extracted from the article]

In order to meet the shape control requirements of "dead flat" transverse thickness profile of electrical steel sheet in cold rolling process, the 3D finite element model (FEM) for roll stacks and strip of 6-high tandem cold rolling mills (TCMs) was built with the developed Edge Drop Control Work Rolls for Non-shifting (EDW-N). The efficiency curves of the work roll bending (WRB), the intermediate roll bending (IRB), and the intermediate roll shifting (IRS) in cold rolling process are obtained for transverse thickness profile control performance. The control strategy of multi-stand and multi-variable profile and flatness control actuators, i.e., WRB, IRB, and IRS of stands 1 ~ 5 in 6-high TCMs is proposed based on the GA-PSO hybrid algorithm with better optimization ability. The results show that the control strategy can fully exploit the shape control ability and achieve the high precision control for transverse thickness profile of 6-high TCMs. The industrial application on the production gives remarkable results that the rate of the measured strip crown less than 7 μm increased from 38.58 to 67.74% for electrical steel sheet in the 1420-mm 6-high TCMs. The control strategy has applied to the production successfully. [ABSTRACT FROM AUTHOR]

Glucose-responsive closed-loop insulin delivery systems represent a promising treatment strategy for diabetes, but current systems generally cannot achieve long-term effects. In this study, we designed an erythrocyte-biomimetic glucose-responsive system (EGRS) by coupling glucose-responsive nanoparticles (GRNs) to red blood cells; these nanoparticles exhibited the dual functions of glucose-responsiveness and persistent presence in circulation. GRNs are generated by encapsulating with insulin through ion crosslinking, followed by coloading with glucose oxidase (GOx) and catalase (CAT), a process that endows the nanoparticles with glucose-responsiveness. Simultaneously, the GRNs are coupled with red blood cells to camouflage them from the immune system, therefore, these erythrocyte-coupled GRNs can circulate in the blood for a long time. Under conditions of hyperglycemia, GOx acts on blood glucose to produce gluconic acid, which causes the rupture of GRNs and efficient release of insulin. Conversely, insulin is only released at the basic rate during hypoglycemia. Thus, EGRS can efficiently and continuously respond to hyperglycemia to maintain blood glucose levels within the normal range. [ABSTRACT FROM AUTHOR]

Laser direct joining of carbon fiber-reinforced thermoplastic composites (CFRTP) to aluminum alloy with diverse surface micro-patterns was performed. The influence of micro-pattern type on interface characteristic and mechanical property of CFRTP/aluminum alloy laser bonding joint was concerned especially. Prior to the laser joining, two different micro-patterns including groove structure and circular hole structure were fabricated on the metal surface using nanosecond pulsed laser. Then, the appearance of joint and the morphology at joining interface were observed by optical microscope and scanning electron microscope. Moreover, the tensile shear test was conducted to obtain the fracture load and fracture surface morphology. The results indicated that the cross section of the groove structure was a trapezoid, while that of the circular hole structure was a triangle with a large ratio of depth to diameter. In spite of the more pores existed at the interface of joints with circular hole structure, this type of micro-pattern strengthened the mechanical anchoring effect between CFRTP and aluminum alloy more significantly. With the change of micro-pattern from groove structure to circular hole structure, the maximum tensile load of laser bonding joint increased from 1616.40 to 2623.40 N, and the main failure mode transformed from interface failure to cohesive failure. The micro-pattern fabricated on the metal surface before the laser joining process is an effective approach to obtain the larger bonding area and higher mechanical strength of laser bonding joint. [ABSTRACT FROM AUTHOR]

As the material experiences non-uniform thermal expansion and contraction under different thermal behavior during laser melting deposition (LMD), the microstructure of the components will be affected, which also causes changes in mechanical properties. It is essential to understand the thermal behavior of the melt pool during LMD to improve the microstructure and joint quality. In this study, two 80-mm-thick Ti6Al4V plates are successfully joined using three different scanning speeds (10, 15, and 20 mm/s). The effects of thermal behavior on the grain morphology and dimension of deposition area, equiaxed crystal zone (EQZ), and the substrate at different scanning speeds are quantitatively analyzed. The results show that the fine equiaxed crystals are formed near the joint boundary due to the high-temperature gradient and cooling rate. The growth direction of fine columnar crystals continuously changes from the joint boundary to the center of the deposition area due to the change of heat-extraction direction. However, the epitaxial growth direction of the coarse columnar crystal is the same as the previous deposition layer at the center of the deposition area. Given the effect of high heat accumulation and low-temperature gradient during LMD, the dimension of columnar crystal is coarsen significantly at the center of the deposition area. [ABSTRACT FROM AUTHOR]

This study aims to investigate the biological role of 6-methyladenine (m6A) methylation in inducing the carcinogenesis of glioma and its proliferation. Relative levels of ALKBH5 and glucose-6-phosphate dehydrogenase (G6PD) in glioma tissues and cell lines were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Gain-of-function and loss-of-function approaches were used to investigate the role of ALKBH5 in mediating proliferation and energy metabolism of glioma cells. The regulatory effect of ALKBH5 on G6PD was analyzed using m6A-qRT-PCR. Our results showed that ALKBH5 was upregulated in glioma, which stimulated glioma cells to proliferate. Serving as a m6A eraser, ALKBH5 demethylated the target transcript G6PD and enhanced its mRNA stability, thereby promoting G6PD translation and activating the pentose phosphate pathway (PPP). Collectively, ALKBH5 stimulates glioma cells to proliferate through erasing the m6A methylation of G6PD, which can be utilized as a potential therapeutic target for glioma. [ABSTRACT FROM AUTHOR]

β-Alanine (3-aminopropionic acid) is the only naturally occurring β-type amino acid. Although it is not incorporated into proteins, it has important physiological functions in the metabolism of animals, plants and microorganisms. Furthermore, it has attracted great interest due to its wide usage as a precursor of many significant industrial chemicals for medicine, feed, food, environmental applications and other fields. With the depletion of fossil fuels and concerns regarding environmental issues, biological production of β-alanine has attracted more attention relative to chemical methods. In this review, we first summarize the pathways through which natural microorganisms synthesize β-alanine. Then, the current research progress in the biological synthesis of β-alanine is also elaborated. Finally, we discuss the main problems and challenges in optimizing the biological pathways, offering perspectives on promising new biological approaches. [ABSTRACT FROM AUTHOR]

Effect of different nitrogen levels (0, 150, and 300 kg hm−2) at booting stage on storage protein biosynthesis and processing quality of wheat was investigated using microstructural and ultrastructural observation, RNA sequencing, and quality analysis in this study. The results showed that the storage protein genes encoding ω- and γ-gliadin and low molecular weight glutenin subunit were upregulated at N150, and the genes encoding α- or β-gliadin and avenin-like protein were upregulated at N300. Two nitrogen levels induced expression of some interesting regulating genes, such as USE1, STX1B_2_3, SEC23, SEC24, SEC61A, HSP A1_8, HSP20, and HSP90B/TRA1. These regulatory genes were enriched in the KEGG pathway protein export, SNARE interactions in vesicular transport, and protein processing in endoplasmic reticulum. The amount, morphology, and accumulation pattern of protein body in four different endosperm regions in developing caryopsis show different response to N150 and N300, of which N300 had greater influence than N150. N150 and N300 both enhanced the contents of protein components, endosperm fullness, grain hardness, and parameters of processing quality, with the latter showing a greater degree of influence. Contrary to the accumulation pattern of protein body, N300 reduced the ratio of the amount of starch granules to the area ratio of protein body to starch granule. Results suggested that the difference of different nitrogen levels affecting storage protein biosynthesis might be through affecting the expression of the encoding and regulating gene of storage protein. [ABSTRACT FROM AUTHOR]

In recent days, Mobile Edge Computing (MEC) emerges as a new computing paradigm that pushes computing resources towards the edge of the Internet and close to end users and more scholars begin to carry out their different kinds of research under the framework of edge computing. Unlike cloud computing however, edge computing often lacks a centralized security mechanism, which increases the security risks of resource consumers. Therefore, to address security issues for facilitating MEC well, we focus on the establishment of an effective trust evaluation system in this paper. We presented a Reputation-based Trust Evaluation and Management (RTEM) system for a secure and efficient MEC network, wherein the edge servers are adopted to execute reputation data management for mobile edge nodes. In this system, a three-tier trust evaluation framework (identity trust, capability trust, behavior trust) was proposed to ensure the edge nodes that join the network system for service interaction are qualified, capable, and reliable. In order to update and calculate reputation data more accurately, we designed a reputation-based trust evaluation model and evaluated the effectiveness and robustness of our designed model on the OMNeT++ platform. The results show that our proposed mechanism can increase the transaction success rate of the edge network by more than two times compared with the network without trust evaluation mechanism, and perform better than the traditional subject logic (TSL) trust evalaution mechanism. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most aggressive astrocytoma. Despite maximum treatment, the GBM usually recurs and the patient survival is poor. Thus, understanding the molecular mechanism of GBM progression will be meaningful to ameliorate this situation. In this study, collapsin response mediator protein 2 (CRMP2) and Ubc9 protein levels were evaluated in three GBM cell lines. Sumoylated CRMP2 were enriched and immunoprecipitated using SUMO1 and IgG antibodies. CRMP2-K374A mutant was generated by site-direct mutagenesis. All indicated constructs were transfected into GL15 cells, and the corresponding proliferation-promoting effect was assessed through cell proliferation ratio. The t-CSM peptide was used to disturb Ubc9-CRMP2 interaction. CRMP2 is expressed in all tested GBM cell lines. The Ubc9 protein levels are positively correlated with CRMP2 level, and both can promote GBM cell proliferation. Blocking CRMP2 SUMOylation through SUMOylation-incompetent mutant or small peptide suppresses CRMP2-induced GBM cell proliferation. This study demonstrates that the CRMP2 SUMOylation exists widely in GBM cells and drives glioblastoma proliferation. CRMP2 SUMOylation inhibition can significantly suppress GBM proliferation in vitro. [ABSTRACT FROM AUTHOR]

It has been reported that matrix metalloproteinases (MMPs) are induced by many cytokines, and they are involved in various inflammatory processes, including periodontitis. However, the effects of interleukin-1β (IL-1β) on MMP-9 expression in cementoblasts, the cells responsible for cementum production, remain largely unknown. In this study, we used qPCR and gelatin zymogram analysis to show that IL-1β upregulated MMP-9 expression in cementoblast-derived cell line. Several signaling pathways, such as ERK1/2, JNK, p38, and AP-1 (c-Fos and ATF-2), were activated in response to IL-1β stimulation. Furthermore, enhancement of AP-1 activity by IL-1β was further confirmed by the AP-1 reporter assay and the electrophoretic mobility shift assay (EMSA). Pretreatment with specific inhibitors of ERK1/2 (U0126), JNK (SP600125), and AP-1 (tanshinone IIA) attenuated IL-1β-induced MMP-9 expression. In addition, inhibitors of ERK1/2 (U0126) and JNK (SP600125) attenuated IL-1β-enhanced AP-1 activity. This suggested that IL-1β stimulated AP-1 activation, at least partially, through ERK1/2 and JNK signaling pathways. Moreover, we found that IL-1β also upregulated the expression of MMP-13 and enhanced MMP-mediated degradation of type I collagen. Collectively, these results suggested that IL-1β induced MMP-9 expression by activation of AP-1 through the ERK1/2 and JNK signaling pathways in cementoblast-derived cell line and enhanced MMP-mediated collagen degradation possibly by MMP-13 and MMP-9. [ABSTRACT FROM AUTHOR]

Autophagy is a self-digestive process that eliminates impaired or aged proteins and potentially toxic intracellular components to maintain homeostasis. We previously demonstrated that TNF-α played a critical role in cementoblast differentiation, mineralization and apoptosis; however, the effect of TNF-α on cementoblast autophagy has remained unclear. In this study, an elevated immunofluorescence signal of LC3B and autophagic vacuoles, autophagosomes and autolysosomes were detected under TNF-α stimulation in OCCM-30 cells. Autophagy-related genes and proteins, Beclin-1, LC3A and Atg-5, were significantly upregulated by TNF-α in a time- and concentration-dependent manner. During this process, the activity of Stat3 was dramatically enhanced and when the activity of Stat3 was blocked by either a specific chemical inhibitor or siRNA transfection before TNF-α stimulation, the TNF-α-induced upregulation of autophagy-related genes and proteins was strongly inhibited. Our results suggest that TNF-α induced autophagy in cementoblasts was dependent, or partially dependent on the activity of Stat3 signaling pathway. [ABSTRACT FROM AUTHOR]

Activation of inflammasome leads to the formation of an inflammatory microenvironment which plays an important role in the process of cancer development. Beta-hydroxybutyrate (BHB) is a ketone body that has recently been reported to exert anti-inflammatory effects via inhibition of NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome. Here, we investigated the potential influence of BHB on the in vitro migration of C6 glioma cells and the activation of NLRP3 inflammasome. Our results indicated that administration of BHB suppressed C6 cells migration and NLRP3 inflammasome activation, reducing the levels of activated cysteinyl aspartate-specific proteinase 1 (caspase-1) and mature Interleukin 1β (IL-1β). Fully activation of NLRP3 inflammasome was induced by lipopolysaccharide (LPS) prime plus adenosine triphosphate (ATP) stimulation in C6 cells, which promoted in vitro migration of C6 cell. BHB also counteracted the LPS/ATP-promoted cell migration by suppressing the activation of caspase-1 and the maturation of IL-1β. The enhancement of phospho-signal transducer and activator of transcription 3 (p-STAT3), degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) as well as the overexpression of fibroblast growth factor 2 (FGF2) resulting from LPS/ATP treatment, and subsequent IL-1β maturation could also be compensated by BHB. Our results suggested that BHB inhibits the activation of NLRP3 inflammasome in C6 glioma cells and consequently suppressed the C6 cell migration. These findings also implicated that by inhibiting NLRP3 inflammasome, BHB reduced the inflammatory microenvironment which provided ancillary therapeutic benefits for the intervention of glioma. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoate (PHA) is a class of microbial synthesized biodegradable and biocompatible aliphatic polymer which has been developed into nanoparticles (NPs) for sustained release of hydrophobic compounds. Taking advantage of the natural PHA binding protein PhaP which could be steadily adsorbed onto PHA NPs through hydrophobic interaction, a tumor targeting system was developed in this study by presenting an epidermal growth factor receptor (EGFR)-targeting peptide (ETP) on the surface of PHA NPs, via PhaP mediated adsorption. To reveal the effects of residual emulsifiers on PhaP mediated ETP modification and optimize the tumor targeting capacity of the system, a novel emulsifier-free PHA NPs (EF-NPs) was fabricated together with other two kinds of conventional emulsifier-required PHA NPs (PVA-NPs and P68-NPs, which were prepared with poly(vinyl alcohol) (PVA) and Pluronic F68 as emulsifiers, respectively). By analyzing the surface hydrophobicity, the amount of adsorbed fusion protein, and the cellular uptake of all kinds of PHA NPs, our results demonstrated that EF-NPs with stronger surface hydrophobicity were the most proper formulation for further PhaP mediated ETP functionalization. The residual PVA and Pluronic F68 affected the modification efficiency and secondary structure of ETP-PhaP fusion protein, and finally obstructed the targeting effect of ETP-PhaP modified PVA-NPs and P68-NPs to EGFR over-expressed tumor cells. The animal experiment further confirmed the effectiveness and feasibility of in vivo application of ETP-PhaP functionalized EF-NPs, indicating that it could be served as a promising tumor targeting system with satisfactory EGFR targeting ability. This PhaP mediated bio-modification process also opens a wide way for developing various PHA-based targeting systems by presenting different tumor or other tissue-specific targeting peptides. [ABSTRACT FROM AUTHOR]

A turbocharger compressor working in commercial vehicles, especially in some passenger cars, often works together with some pipes with complicated geometry as an air intake system, due to limit of available space in internal combustion engine compartments. These pipes may generate various distortions of physical parameters of the air at the inlet of the compressor and therefore the compressor aerodynamic performance deteriorates. Sometimes, the turbocharging engine fails to work at some operation points. This paper investigates the effects of various swirl distortions induced by different bending-torsional intake ducts on the aerodynamic performance of a turbocharger compressor by both 3D numerical simulations and experimental measurements. It was found that at the outlet of the pipes the different inlet ducts can generate different swirl distortions, twin vortices and bulk-like vortices with different rotating directions. Among them, the bulk-like vortices not only affect seriously the pressure distribution in the impeller domain, but also significantly deteriorate the compressor performance, especially at high flow rate region. And the rotating direction of the bulk-like vortices is also closely associated with the efficiency penalty. Besides the efficiency, the transient flow rate through a single impeller channel, or the asymmetric mass flow crossing the whole impeller, can be influenced by two disturbances. One is from the upstream bending-torsional ducts; other one is from the downstream volute. [ABSTRACT FROM AUTHOR]

In this investigation, a sinusoid modulated pulse gas metal arc welding (SP-GMAW) method based on a current waveform control method and on the welding mechanism of pulsed gas metal arc welding (P-GMAW) was proposed. This method achieved smooth control over the welding current. The process formulas were simplified. Then, the control parameters were discussed and optimized. Finally, three comparison experiments were conducted. The results indicated that the SP-GMAW method, as an improved double-pulsed gas metal arc welding (DP-GMAW) method, had the following features: The SP-GMAW minimized porosity rate and generated palpable weld ripples in contrast with the P-GMAW. The SP-GMAW produced the finest fusion zone grain, highest fusion zone microhardness, and highest tensile strength among three welding methods. The feasibility and superiority of the method for welding aluminum sheet were verified. [ABSTRACT FROM AUTHOR]

The flow field distribution in centrifugal compressor is significantly affected by the non-axisymmetric geometry structure of the volute. The experimental and numerical simulation methods were adopted in this work to study the compressor flow field distribution with different flow conditions. The results show that the pressure distributionin volute is characterized by the circumferential non-uniform phenomenon and the pressure fluctuation on the high static pressure zone propagates reversely to upstream, which results in the non-axisymmetric flow inside the compressor. The non-uniform level of pressure distribution in large flow condition is higher than that in small flow condition, its effect on the upstream flow field is also stronger. Additionally, the non-uniform circumferential pressure distribution in volute brings the non-axisymmetric flow at impeller outlet. In different flow conditions,the circumferential variation of the absolute flow angle at impeller outlet is also different. Meanwhile, the non-axisymmetric flow characteristics in internal impeller can be also reflected by the distribution of the mass flow. The high static pressure region of the volute corresponds to the decrease of mass flow in upstream blade channel, while the low static pressure zone of the volute corresponds to the increase of the mass flow. In small flow condition, the mass flow difference in the blade channel is bigger than that in the large flow condition. [ABSTRACT FROM AUTHOR]

We reported the synthesis of polystyrene@(silver-polypyrrole) (PS@(Ag-PPy)) nanocomposite microspheres with the well-defined core/shell structure, in which the functionalized PS microspheres by the sulfonic acid groups were employed as template. The diameter of the synthesized PS microsphere template and AgNP was 1.26 μm and 50 nm, respectively. In order to well control the redox reaction between Ag and Py monomer and to avoid the accumulation of these AgNPs during synthesis process, the complexation of triethanolamine (TEA) and silver ion ([Ag(TEA)]) was employed as the oxidant, so that the generation rate of AgNPs was in turn decreased. Moreover, compared with the redox reaction between AgNO and Py, the introduction of [Ag(TEA)] ions resulted in the improved coverage and distribution of AgNPs around the surface of PS microspheres. Meanwhile, the loading amount of Ag-PPy nanocomposites on the final microspheres was adjustable. The increasing concentrations of Py monomer and [Ag(TEA)] ions resulted in the increase of Ag-PPy nanocomposite loading. The results of antibacterial experiment suggested that the synthesized PS@(Ag-PPy) composite microspheres showed the prominent antibacterial properties against both the Gram-negative bacteria of Escherichia coli and the Gram-positive bacteria of Staphylococcus aureus. For the bacteria with concentration at 1 × 10 - 9×10 cfu/mL, the microspheres can kill the bacteria above 3-log reduction with the concentration of PS@(Ag-PPy) composite microspheres at 50 μg/mL, in which the weight fraction of Py in the composite microspheres was above 10 wt%. When the weight fraction of Py in the composite microspheres was at 5 wt%, the 2-log reduction of in bacterial viability could also be obtained. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Macrophage scavenger receptor 1 (MSR1) mediates the endocytosis of modified low-density lipoproteins and plays an important antiviral role. However, the molecular mechanism underlying MSR1 antiviral actions remains elusive. We report that MSR1 activates autophagy to restrict infection of Chikungunya virus (CHIKV), an arthritogenic alphavirus that causes acute and chronic crippling arthralgia. Msr1 expression was rapidly upregulated after CHIKV infection in mice. Msr1 knockout mice had elevated viral loads and increased susceptibility to CHIKV arthritis along with a normal type I IFN response. Induction of LC3 lipidation by CHIKV, a marker of autophagy, was reduced in Msr1−/− cells. Mechanistically, MSR1 interacted with ATG12 through its cytoplasmic tail and this interaction was enhanced by CHIKV nsP1 protein. MSR1 repressed CHIKV replication through ATG5-ATG12-ATG16L1 and this was dependent on the FIP200-and-WIPI2-binding domain, but not the WD40 domain of ATG16L1. Our results elucidate an antiviral role for MSR1 involving the autophagic function of ATG5-ATG12-ATG16L1. Using Msr1 knockout mice, Long Yang et al. demonstrate that macrophage scavenger receptor 1 (MSR1) activates autophagy to restrict the proliferation of Chikungunya virus, an alphavirus that causes crippling joint stiffness. This study provides insights into how host cellular machinery fights off Chikungunya virus. [ABSTRACT FROM AUTHOR]

In this study we quantified the alterations of retinal histone post-translational modifications (PTMs) in diabetic rats using a liquid chromatography - tandem mass spectrometry (LC-MS/MS) approach. Some diabetic rats were subsequently treated with minocycline, a tetracycline antibiotic, which has been shown to inhibit the diabetes-induced chronic inflammation in the retinas of rodents. We quantified 266 differentially modified histone peptides, including 48 out of 83 methylation marks with significantly different abundancein retinas of diabetic rats as compared to non-diabetic controls. About 67% of these marks had their relative abundance restored to non-diabetic levels after minocycline treatment. Mono- and di-methylation states of histone H4 lysine 20 (H4K20me1/me2), markers related to DNA damage response, were found to be up-regulated in the retinas of diabetic rats and restored to control levels upon minocycline treatment. DNA damage response biomarkers showed the same pattern once quantified by western blotting. Collectively, this study indicates that alteration of some histone methylation levels is associated with the development of diabetic retinopathy in rodents, and the beneficial effect of minocycline on the retinas of diabetic rodents is partially through its ability to normalize the altered histone methylation levels. [ABSTRACT FROM AUTHOR]

A C-type lectin (CfLec-3) from Chlamys farreri with three carbohydrate-recognition domains (CRDs) was selected to dissect the possible mechanisms of PAMP binding and functional differentiation of invertebrate lectins. CfLec-3 distributed broadly, and its mRNA expression in hemocytes increased significantly after stimulations with LPS, PGN or β-glucan, but not poly(I:C). The recombinant CfLec-3 (rCfLec-3) could bind PAMPs and several microbes. rCfLec-3 mediated hemocytes phagocytosis against Escherichia coli and encapsulation towards agarose beads. Obvious functional differentiation occurred among the three CRDs, as CRD1 exhibited higher activity to bind PAMPs, while CRD2/3 were expert in promoting hemocyte mediated opsonisation. The tertiary structural differences were suspected to be associated with such functional differentiation. PAMP binding abilities of CfLec-3 were determined by Ca2+-binding site 2 motif. When Pro in this motif of each CRD was mutated into Ser, their PAMP binding abilities were deprived absolutely. rCRD2 acquired mannan binding capability when its EPD was replaced by EPN, but lost when EPN in rCRD3 was changed into EPD. The Pro in Ca2+-binding site 2 was indispensable for PAMPs binding, while Asn was determinant for specific binding to mannan. It shed new insight into PAMPs binding mechanism of invertebrate C-type lectins and their functional differentiation. [ABSTRACT FROM AUTHOR]

Considering the unique soil structure and the temperature rise effect of seawater’s electrical and thermal parameters, accurately simulating the grounding characteristics of marine DC grounding electrodes is the basis for ensuring the safe and stable operation of offshore wind power grid-connected DC projects. The paper proposes a dynamic finite element model of ocean grounding electrode characteristics based on the coupling of circuits and electrical–thermal fields. In the finite element model, soil parameters can be controlled by the time-varying temperature distribution, and the dynamic process of the coupling of soil electrical and thermal fields in the process of direct flow can be accurately simulated. A time-varying equivalent circuit model for controlling the electric–thermal field can be implemented to accurately simulate the dynamic process of the shunt coefficient for each conductor segment in a composite DC grounding electrode with multiple injection points. The effectiveness is verified by comparing with the experimental data. Finally, the dynamic flow process, temperature rise process and their mutual influence are quantitatively analyzed. [ABSTRACT FROM AUTHOR]