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In this work, a hot extrusion forming process for magnesium (Mg) alloy square tubes, namely, tube-extrusion-continuous expending shear (TECES), was proposed. The thin-walled hollow square tube of Mg alloy with a thickness of 3 mm was successfully prepared by hot extrusion experiment. The evolution rules of effective stress, effective strain, and flow velocity in the process of tube forming were analyzed by numerical simulation, and the influence of different expanding ratios on tube forming was compared. The results show that the effective stress distribution of the tube is not uniform during the forming process, and the maximum stress appears at the first shear corner. In the shear deformation (SD) zone, there is a high strain zone at the corner of the square tube and outside the tube wall. As the tube is extruded, the uniformity of strain distribution in the deformation zone is improved. In the whole forming process, the flow rate of the tube increases first and then decreases, and the whole remains stable. As the expansion ratio increases when the expansion ratio is greater than 1.6, the resistance of plastic deformation increases, the fluidity of the metal becomes worse, and the formed tube cracks at the corner or is difficult to fill. When the expansion ratio is less than 1.6, the damage value area appears on the inner side of the tube wall, and the distribution uniformity is poor, which may lead to cracks or uneven thickness of the tube wall. The microstructure characterization of different deformation zones of the tube was carried out, and the results show that the TECES process can effectively refine the grain, and the average grain size of the formed tube is 10.1 μm. [ABSTRACT FROM AUTHOR]

Purpose: Cone-beam computed tomography (CBCT) was used in this study for evaluating the diameter, prevalence, spatial location, and risk factors of the accessory canal (AC) of the canalis sinuosus. Methods: A comprehensive assessment of the incidence rate, diameter, three-dimensional (3D) spatial location, and direction of travel of AC was performed on 1003 CBCT images. The CBCT data were used to reconstruct a 3D model of the maxilla to determine the alveolar bone volume. The obtained data were further analyzed and processed. Results: AC was present in 50.1% of images. Male patients more frequently had ACs than female patients did (P < 0.01) and was positively correlated with the maxillary alveolar bone volume (P < 0.001, OR 1.532). Age or nasopalatine canal diameter were not significantly associated with the occurrence of AC (P > 0.05). Among the 502 patients with AC, AC was present on the left side, right side, and bilaterally in 189, 98, and 215, respectively. The maximum number of ACs observed per individual was eight. The average AC diameter was 0.89 ± 0.26 mm (minimum, 0.5 mm; maximum, 2.02 mm). Conclusions: As the prevalence of AC and its trajectory display considerable variation among individuals, surgeons must consider the possibility of the presence of AC when devising surgical plans involving the anterior maxillary region. [ABSTRACT FROM AUTHOR]

This study proposed the direct extrusion and continuous-shear deformation (DECS) process for the co-extrusion of Mg-AZ31B/Al 6063, aiming to prepare high-plasticity Mg/Al composite sheets. The effect of extrusion temperature on the microstructure and mechanical properties of the Mg/Al composite sheet was systematically studied. The results show that Mg/Al composite sheets with no voids or cracks at the interface were successfully prepared by the DECS process. The microstructure of the Mg layer at different extrusion temperatures primarily consists of equiaxed fine grains, with grain sizes of 7.29 μm, 8.98 μm, and 9.88 μm at 330℃, 360℃, and 390℃, respectively. The Mg layer exhibits a typical extrusion texture, with the c-axis of most grains parallel to the transverse direction (TD). With the increase in extrusion temperature, the c-axis of some grains deviates from the TD toward the normal direction (ND). The Al layer mainly consists of elongated deformed grains and fine dynamically recrystallized (DRXed) grains distributed along the extrusion direction (ED). The AZ31 Mg alloy with refined grains maintains the ultimate tensile strength of the Mg/Al composite sheet, while the Al matrix enhances its plasticity. At 330℃, the Mg/Al composite sheet shows an ultimate tensile strength of 244.48 MPa ± 4.35 and an elongation of 39.42% ± 0.06. The influence of the bonding layer thickness on the shear and tensile properties of the composite sheet was studied, revealing that increasing the bonding layer thickness reduces the shear strength of the Mg/Al composite sheet but positively affects its tensile strength. [ABSTRACT FROM AUTHOR]

It is widely accepted that substantial nighttime sap flux ( J) or transpiration ( E) occurs in most plants, but the physiological implications are poorly known. It has been hypothesized that J or E serves to enhance nitrogen uptake or deliver oxygen; however, no clear evidence is currently available. In this study, sap flux ( J) in Eucalyptus grandis × urophylla with apparent stem photosynthesis was measured, including control trees which were covered by aluminum foil (approximately 1/3 of tree height) to block stem photosynthesis. We hypothesized that the nighttime water flux would be suppressed in trees with lower stem photosynthesis. The results showed that the green tissue degraded after 3 months, demonstrating a decrease in stem photosynthesis. The daytime J decreased by 21.47 %, while J decreased by 12.03 % in covered trees as compared to that of control, and the difference was statistically significant ( P < 0.01). The linear quantile regression model showed that J decreased for a given daytime transpiration water loss, indicating that J was suppressed by lower stem photosynthesis in covered trees. Predawn ( ψ) of covered trees was marginally higher than that of control while lower at predawn stomatal conductance ( g), indicating a suppressed water flux in covered trees. There was no difference in leaf carbon content and δC between the two groups, while leaf nitrogen content and δN were significantly higher in covered trees than that of the control ( P < 0.05), indicating that J was not used for nitrogen uptake. These results suggest that J may act as an oxygen pathway since green tissue has a higher respiration or oxygen demand than non-green tissue. Thus, this study demonstrated the physiological implications of J and the possible benefits of nighttime water use or E by the tree. [ABSTRACT FROM AUTHOR]

Canopy stomatal ozone (O 3 ) flux ( F st,O3 ) in a plantation of Schima superba , an ecologically and economically important evergreen pioneer tree species in subtropical China, was quantified based on sap flow measurements during a 2-year period. Mean F st,O3 and accumulated F st,O3 ( AF st 0) were significantly higher in wet seasons from April to September (4.62 nmol m − 2 s − 1 and 35.37 mmol m − 2 , respectively) than in dry seasons from October to March (3.90 nmol m − 2 s − 1 and 24.15 mmol m − 1 , respectively), yet comparable between the 2 years of the experiment, being 4.23 nmol m − 2 s − 1 and 58.23 mmol m − 2 in April 2013–March 2014 and 4.29 nmol m − 2 s − 1 and 60.80 mmol m − 2 in April 2014–March 2015, respectively. At the diurnal scale, F st,O3 generally peaked in the early to middle afternoon hours (13:00–15:00), while the maximum stomatal conductance ( G st,O3 ) typically occurred in the middle to late morning hours (09:00–11:00). Monthly integrated AF st 0 reached the maximum in July, although accumulated O 3 exposure ( SUM 0) was highest in October. Seasonally or yearly, the accumulated O 3 doses, either exposure-based or flux-based, notably exceeded the currently adopted critical thresholds for the protection of forest trees. These results, on the one hand, demonstrated the decoupling between the stomatal uptake of O 3 and its environmental exposure level; on the other hand, indicated the potential O 3 risk for S. superba in the experimental site. Therefore, the present study endorses the use of sap flow measurements as a feasible tool for estimating F st,O3 , and the transition from the exposure-based toward flux-based metrics for assessing O 3 risk for forest trees. Further studies are urgently needed to relate stomatal O 3 uptake doses with tree growth reductions for an improved understanding of O 3 effects on trees under natural conditions. [ABSTRACT FROM AUTHOR]

In this study, Mg/Al bimetallic composite tubes were prepared by direct extrusion-shear deformation (DESD) process. First, the influence of the shear deformation process on the bonding of Mg/Al composite tubes was determined. The results showed that compared with the direct extrusion process, the addition of shear deformation led to a bonding layer without cracks or defects. Second, the interfacial microstructure, texture evolution and mechanical properties of Mg/Al composite tubes subjected to different preheating temperatures were systematically studied. With increasing preheating temperature, the microstructure of the Mg layer showed uniform growth, while the microstructure of the Al layer grew which led to an increase in the basal texture intensity. The thickness of the intermetallic compounds (IMCs) increased as the preheating temperature was increased, while the bonding strength decreased. The decreased bonding strength was attributed to grain growth of the IMCs and hard-oriented grains near the Al side. In addition, the microstructure evolution of the Mg and Al layers in the DESD process was analysed. The results showed that shear deformation can effectively weaken the basal texture intensity of the Mg alloy and induce the transformation of the Al alloy texture from the deformation texture (Copper, Goss and S) to the recrystallization texture (Cube). [ABSTRACT FROM AUTHOR]

We prepared multifunctional nanoparticles (EGAP) with antibacterial, antioxidant, anti-inflammatory, oxygen supply, pro-angiogenic and good biocompatibility, then encapsulated them in temperature-sensitive hydrogels and applied them to chronic wounds, and finally improved the complex local microenvironment of diabetic wounds by local injection to accelerate wound healing. [Display omitted] • Chronic wound ulcers is a serious complication of diabetes. • The microenvironment of diabetic wounds is sophisticated and detrimental to tissue restoration. • Catalase-like nanozymes (GAP) improve the hypoxic environment of wounds. • Multifunctional nanomedicines (EGAP@HG) can reverse the unfavorable microenvironment and promote ulcer healing. Diabetic wounds have a complex microenvironment, due to local hypoxia, bacterial infection, and the accumulation of reactive oxygen species. Multiple adverse factors contribute to the non-healing state. Without effective treatment, diabetic wounds can lead to serious systemic complications. The current clinical treatments of enhanced glycemic control and anti-infection are unable to meet the needs of diabetic wound management. Here, we constructed a nanoparticle with catalase-like functionality (EGAP) and encapsulated it in a thermosensitive hydrogel to yield a versatile hydrogel formulation (EGAP@HG). The drug can form a protective physical barrier over the wound and create a moist environment. First, the EGAP converts H 2 O 2 to O 2 at the wound site, thereby alleviating local hypoxia. Then, the released EGF can promote the proliferation of epidermal cells. Furthermore, the gallic acid released from the outer layer of EGAP can exert anti-inflammatory and antioxidant effects. Finally, the silver ions released from the inner templates (APs) can kill bacteria. In vivo and in vitro experiments have shown that our treatment system can promote wound healing from multiple perspectives. This strategy by improving the local microenvironment of diabetic wounds provides a new theoretical basis and practical directions for chronic diabetic wound repair. [ABSTRACT FROM AUTHOR]

RBCs undergo numerous changes during storage and stored RBCs may induce adverse effects, ultimately resulting in organ injury in transfusion recipients. We tested the hypothesis that the addition of SP to stored RBCs would improve the quality of the stored RBCs and mitigate liver injury after transfusion in a murine model. RBCs were harvested from C57BL/6J mice and stored for 14 days in CPDA-1 containing either a solution of SP in saline or saline alone. Haemolysis, the 24-hour posttransfusion recovery, the oxygen-carrying capacity, and the SOD activity of stored RBCs were evaluated. The plasma biochemistry, hepatic MDA level, MPO activity, IL-6, TNF-α concentrations, and histopathology were measured two hours after the transfusion of stored RBCs. Compared with RBCs stored in CPDA-1 and saline, the addition of SP to stored RBCs restored their oxygen-carrying capacity and SOD activity, reduced the AST activity, BUN concentrations, and LDH activity in the plasma, and decreased the MDA level, MPO activity, and concentrations of IL-6 and TNF-α in the liver. These data indicate that the addition of SP to RBCs during storage has a beneficial effect on storage lesions in vitro and subsequently alleviates liver injury after the transfusion of stored RBCs in vivo. [ABSTRACT FROM AUTHOR]

Measuring road safety achievement through persistent monitoring of subjects, such that they can learn from one another, has been widely encouraged by various countries to support policymaking. In recent decades, the Asia-Pacific Economic Cooperation (APEC) countries have been working together to improve road safety, considering it an important constituent and reflection of their economic development. However, no uniform road safety measurement framework is currently available across the APEC. To this end, the current study develops a practical and efficient methodology, namely, the entropy weight method (EWM) – grey relational analysis (GRA) – singular value decomposition (SVD) (EWM-GRA-SVD), providing government officials and policymakers with a replicable framework for reporting the road safety achievement of countries. The EWM is employed to obtain the weights of the set of indicators, as the weighting inputs of GRA, to form a composite score for ranking, where the SVD is embedded in the GRA for grouping by means of extracting singular values. Using the proposed model, best-performing and underperforming countries are distinguished, whereby each country could learn from others within their assigned group based on an overview of achievements and progress in road safety over the past decade. The results enable decision-makers and policymakers to develop action plans and consider necessary interventions promptly and effectively. [ABSTRACT FROM AUTHOR]

Canopy stomatal uptake of NO X (NO, NO 2 ), SO 2 and O 3 by three mature urban plantations (of Schima superba, Eucalyptus citriodora and Acacia auriculaeformis ) were studied using the sap flow-based approach under free atmospheric conditions. The annual mean concentration for NO, NO 2 , SO 2 and O 3 were 18.2, 58.1, 12.8 and 42.4 μg m −3 , respectively. The atmospheric concentration exhibited a spring or winter maximum for NO, NO 2 and SO 2 , whereas the concentration maximum for O 3 occurred in the autumn. Despite the daytime mean canopy stomatal conductance ( G C ) being positively related with the photosynthetically active radiation ( PAR ) and negatively with the vapour pressure deficit ( VPD ), the maximal daytime mean G C did not appear when the PAR was at its highest level or the VPD was at its lowest level because a positive correlation was noted between the daytime mean PAR and VPD ( P < 0.001) under field conditions. The G C value was regulated by the cooperation of the PAR and VPD . When analysing the respective effect of the PAR or VPD on G C separately, a positive logarithmical correlation was noted between the daytime mean G C and PAR as the following equation: G c = a × lnPAR − b ( P < 0.01), and the daytime mean G C was negatively logarithmically correlated with the VPD : G c = G sref − m × lnVPD ( P < 0.001). The daytime mean G C declined with decreases in the soil water content ( SWC ) under similar meteorological condition. Differences in the seasonal pattern of the canopy stomatal conductance and atmospheric concentrations led to a differentiated peak flux. The flux for NO, NO 2 and SO 2 exhibited a spring maximum, whereas the flux maximum for O 3 appeared in the autumn or summer. The annual cumulative stomatal flux for NO, NO 2 , O 3 and SO 2 was 100.19 ± 3.76, 510.68 ± 24.78, 748.59 ± 52.81 and 151.98 ± 9.33 mg m −2 a −1 , respectively. When we focus on the foliar uptake of trace gases, the effect of these gases on the vegetation in turn should be considered, particularly for regions with serious air pollution problems. These trace gases had not yet reached injury levels, except for NO 2 . Flux-based measurements were better suited for evaluating the risk of O 3 damage to vegetation than the exposure-based method. [ABSTRACT FROM AUTHOR]

Cycling benefits both the individual and society in terms of public health promotion, traffic congestion relief and vehicle emissions reduction. To better understand cycling behaviors, we analyze non-linear relationships and interaction effects between the built environment and cycling distance. Few studies explore the interaction effects on cycling distance in which road network patterns interact with the demographic, trip, and other built environment characteristics to produce complex effects. Previous research has not examined the effect size or relative contribution of various variables have on cycling distance. Thus, this study adopts eXtreme Gradient Boosting (XGBoost) to examine the non-linear relationships among road network patterns, demographic, trip, and bike lane infrastructure, and other built environment characteristics and cycling distance, and employs SHapley Additive exPlanations (SHAP) to discover complex interaction effects on cycling distance, based on a bike travel survey in Xi'an, China. The results show that road network patterns have the greatest contribution; bike lane infrastructure is also quite important and has larger collective contributions than land use patterns and socioeconomics. Average geodesic distance and network betweenness centrality, two topological indices to describe road network structure, interact with bike lane infrastructure, land use and demographic characteristics to produce interaction effects on explaining cycling behaviors. When the average geodesic distance is smaller than 2.8 and the network betweenness centrality is smaller than 50%; as average geodesic distance increases, the network betweenness centrality has a positive effect on cycling distance. A network with a lower average geodesic distance, and with a higher intersection density makes cyclists ride a longer distance. A network with a higher value of average geodesic distance discourages cyclists to detour. [ABSTRACT FROM AUTHOR]