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Owing to the layer-by-layer deposition characteristic of fused deposition modeling (FDM) process, parts produced via FDM have typical low surface quality and do not satisfy the requirements for end-use applications. Therefore, it is necessary to improve the surface quality of parts produced via FDM. In this study, laser polishing technology was employed to enhance the surface quality of aluminum fiber/polylactide acid (Al/PLA) composite parts produced via FDM. The surface roughness, surface morphology, dynamic mechanical properties, and tensile properties were investigated. With optimal polishing parameters, the laser polishing process removed the defects formed during the FDM process. The surface roughness was reduced from the initial value of 5.64 μm to 0.32 μm (Ra). The dynamic mechanical analysis (DMA) results showed that there was a remarkable improvement in the storage modulus (E ′), loss modulus (E "), and glass transition temperature of Al/PLA composite specimens after laser polishing. The re-melted and polished surface of the specimens also led to improvement in the tensile strength and Young's modulus. Lastly, the fracture morphologies were observed, and the possible strengthening mechanism was also discussed. These results indicate that laser polishing can be an efficient method for the surface polishing of FDM-printed parts. Unlabelled Image • Laser polished additive manufactured Al/PLA has higher surface quality and many defects are removed. • A maximum reduction in Al/PLA surface roughness of over 93% is achieved at optimized polishing settings. • Laser polishing effectively improves the dynamic mechanical properties and tensile properties of the FMD Al/PLA. • The strengthening mechanism induced by laser polishing is analyzed. [ABSTRACT FROM AUTHOR]

• Pores- and cracks-free TiC/IN625 coatings over AISI 1045 steel were firstly prepared by EHLA. • EHLA TiC/IN625 coatings possessed much more uniform and finer microstructure. • High resistance is attributed to lower surface roughness, smaller dendrite size, smaller grain size, and higher amount of LAGBs. The multi-layer TiC/IN625 coatings were deposited on AISI 1045 steel substrate by conventional laser cladding (CLA) and extreme high-speed laser cladding (EHLA). The surface morphology, microstructure and high-temperature oxidation resistance of the TiC/IN625 coatings were characterized and compared. The results showed that the cladding speed has a significant effect on surface quality. Within the range of the set parameters, the best surface quality is obtained when the cladding speed is 49.8 m/min, where Ra is 11.75 μm and Sa is 13.17 μm. The microstructure of the TiC/IN625 coatings is dominated by dendrites. Smaller dendrites arm spacing and no apparent transition layer are found at the layer-to-layer interface in the EHLA sample. A two-layered oxide structure is formed in the cross-section of all samples. The EHLA sample exhibits a lower mass loss compared to the CLA sample, indicating that EHLA sample can withstand high-temperature oxidation. The improvement of high-temperature oxidation resistance is mainly attributed to the lower surface roughness, smaller dendrite size, smaller grain size, and higher amount of LAGBs. [ABSTRACT FROM AUTHOR]

Extreme high-speed laser cladding (EHLA) was used to develop a pore- and crack-free TiC/IN625 coating. The surface roughness of EHLA could be as low as 6.004 µm. A more uniform dendrite size and composition distribution was obtained by EHLA. The mass gain of EHLA was 57.5% lower than that of the conventional laser cladding sample after hot corrosion in a mixed salt of 75%Na 2 SO 4 + 25% NaCl at 900 ℃ for 60 h. High hot corrosion resistance of EHLA was mainly attributed to the lower surface roughness, smaller dendrite size, smaller grain size, and higher amount of low-angle grain boundaries. • Pores- and cracks-free TiC/IN625 coatings over AISI 1045 steel were firstly prepared by EHLA. • EHLA TiC/IN625 coatings possessed much more uniform and finer microstructure. • The uniformly distributed dendrite sizes and compositions contributed to the formation of a dense oxide film. • Superior hot corrosion behavior of EHLA TiC/IN625 coatings was mainly attributed to the lower surface roughness, smaller dendrite size, smaller grain size, and more low-angle grain boundaries. [ABSTRACT FROM AUTHOR]

• The combined toolbox (Wondfo RDTs plus microscopy) improved the surveillance system sensitivity for malaria in Anhui province. • The improvement was mainly attributed to the excellent ability of RDTs to detect P. falciparum infections. On the other hand, microscopy compensates for some limitations of the use of RDTs in field practice. • Using more than one diagnostic tool to strengthen the surveillance system was effective in the post-elimination stage. Background: In the Anhui Province, China, efforts to interrupt the local malaria transmission were successful, with no endemic cases reported since 2014. Contrastingly, imported malaria cases are still being reported, indicating a disease reintroduction risk after years of elimination. A good surveillance system is key for avoiding the risk, detecting imported cases and possible cases associated with local transmission early. Therefore, rapid diagnostic tests (RDTs) were combined with microscopy to strengthen malaria surveillance in the province. Herein, we aimed to evaluate the efficacy of this surveillance strategy. Methods: We conducted a retrospective study using malaria surveillance data from January 2016 to June 2020. Epidemiological characteristics and diagnostic information were analysed using descriptive and comparative statistics. The diagnostic performance of the combined toolbox (Wondfo RDTs plus microscopy) was evaluated based on its sensitivity, specificity, positive and negative predictive values, and Cohen's kappa coefficient, using real-time polymerase chain reaction as the gold standard. Results: The combined toolbox displayed a higher overall sensitivity for malaria cases than that of microscopy alone (93.74% vs 89.37%; p adj <0.05), which could detect 94.65%, 88.16%, 95.00%, and 100.00% of Plasmodium falciparum, P. ovale, P. vivax , and P. malariae infections, respectively. In clinical practice, Wondfo RDTs ability to detect P. falciparum infections was better than that of microscopy (97.55% vs 89.67%, p adj < 0.05). In contrast, microscopy displayed a higher specificity than that of Wondfo RDTs (81.82% vs 63.28%, p adj <0.05). Moreover, the consistency between microscopy and the gold standard results was also better than that of RDTs (Kappa value:0.669 vs 0.596). Conclusions: The combination of microscopy and RDTs is an effective strategy for malaria surveillance because it possibly detected more P. falciparum infections due to the introduction of RDTs. In contrast, microscopy is complementary to some limitations related to the use of RDTs in field practice. Thus, monitoring malaria cases in non-endemic areas may require employing more than one diagnostic tool in surveillance strategies. Moreover, further understanding of the advantages and disadvantages of different detection methods is necessary for applying optimum combinations in field settings. [ABSTRACT FROM AUTHOR]

Although fused deposition modeling (FDM) has gradually become one of the popular additive manufacturing technologies in different industries, high surface roughness has always been an inevitable disadvantage of FDM parts. Laser polishing represents a recent and novel application of laser surface irradiation that can be used for precise, post-process smoothing of the rough surfaces commonly encountered on FDM parts. The influence of laser polishing on surface modification and mechanical properties of aluminum/Polylactic Acid (Al/PLA) composites has been investigated. Laser scanning speed was varied to evaluate its effect on the surface quality and mechanical properties of the experimental samples. The results indicated that laser polishing could enable reductions in surface roughness of over 86.6% (from 23.27 μm to 3.11 μm Sa). The tensile strength of specimen also increased from 41.01 MPa to 51.31 MPa with increasement of 25.1%. The dynamic mechanical analysis (DMA) results showed that there was a remarkable improvement in the storage modulus and glass transition temperature of Al/PLA composite specimens after laser polishing, which suggested that the laser polishing treatment could play a role in decreasing the porosity inside the FDM parts and improve interfacial adhesion between the PLA matrix and Al fibers. Moreover, the fracture morphologies were observed to investigate the possible strengthening mechanism. These results demonstrate how laser polishing can simultaneously smooth and modify the surface characteristics of a FDM part surface. Image 1 • Laser polished additive manufactured Al/PLA has higher surface quality and many defects are removed. • A maximum reduction in Al/PLA surface roughness is achieved at optimized polishing settings (laser scan speed of 100 mm/s). • Laser polishing effectively improves the dynamic mechanical properties and tensile properties of the FMD Al/PLA. • After laser polishing treated, Al/PLA composite specimens had a higher storage modulus and glass transition temperature. • The strengthening mechanism induced by laser polishing is analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Relatively dense multilayer AA6061 alloys were manufactured by AFSD. • The AFSD AA6061 alloy exhibited refinement microstructure with absent of β″ strengthening phases. • The microstructural evolution of AFSD AA6061 alloy before and after heat treatment was investigated. • The electrochemical corrosion behavior and mechanism of AFSD AA6061 alloy were studied. Multilayer AA6061 aluminum alloy components were successfully fabricated by additive friction stir deposition (AFSD). The effect of heat treatment on the microstructure and electrochemical corrosion behavior of the AA6061-T6 aluminum alloy components was studied. The average grain size in AFSD samples was 2.67 μm, where 89.7 % of grains were smaller than 5 μm. Abnormal grain growth was observed in the heat-treated AFSD (AFSD-HT) sample, and the average grain size of AFSD-HT sample was 592 μm. In the base material (BM) sample, apart from the β″ strengthening phases, hard-brittle Al 5 FeSi intermetallic compounds (IMCs) aggregated along the boundaries of the coarser grains. Due to the high temperature generated during the process of AFSD, β″ phases dissolved into the matrix. After heat treatment, a larger amount of fine needle-like β″ phases were re-precipitated in the AFSD-HT sample. Al 5 FeSi IMCs accelerated the corrosion of the Al matrix. Fine β″ phases significantly inhibited the corrosion expansion to Al matrix and improved the corrosion resistance of AA6061 alloys. [ABSTRACT FROM AUTHOR]

Refractory high-entropy alloys (RHEAs) are a new category of high-temperature materials that are high-entropy alloys with refractory metal elements as the major components. SLM technique provides distinct benefits in preparing refractory metals with high melting points. The effects of laser power and scanning speed on the surface morphology and internal defects of VNbMoTaW RHEAs samples were examined using numerical and experimental methods. A DEM-CFD model was created to simulate the process of SLM producing a single-layer, single-track model. The simulation findings show that the melt pool's channel width is 62.31 μm at a scanning speed of 300 mm/s and a laser power of 150 W. The channel width grows to 96.92 μm when the laser power rises to 450 W. When the laser power is increased, the channel becomes flatter. To prepare the VNbMoTaW samples, the process parameters with the highest quality in the numerical simulation were chosen. At a scanning speed of 300 mm/s and a laser power of 450 W, the measured channel width of the high-entropy alloy samples is approximately 104.13 m. Similarly to the numerical simulation results, the channel width of the models generated at the same scanning speed increases as the laser power increases. At low laser power, it was discovered that many unmelted powder particles were dispersed on the surface of the samples. The primary defects found in the samples were pores and fractures. The interlayer non-melting cracks on the sample cross-section vanish at elevated laser power. Whereas the quality of samples created at low scanning speeds is higher at the same laser power, the quality of samples declines as the scanning speed of the laser increases. • The forming process of VNbMoTaW RHEAs by SLM was firstly simulated numerically. • Process parameters such as laser power and scanning speed affected the RHEAs surface morphology. • The experimental results were in good agreement with the simulation rules. • Pores and cracks are the main defects in the RHEAs alloys and cannot be completely avoided. [ABSTRACT FROM AUTHOR]

The prevalence of ferroptosis in diabetic kidney tubules has been documented, yet the underlying mechanism remains elusive. The aim of this study was to ascertain the pivotal gene linked to ferroptosis and establish a novel target for the prevention and management of diabetic kidney disease (DKD). Transcriptomics data (GSE184836) from DKD mice (C57BLKS/J) were retrieved from the GEO database and intersected with ferroptosis-related genes from FerrDb. Then, differentially expressed genes associated with ferroptosis in the glomeruli and tubules were screened. Gene ontology analysis and protein-protein interaction network construction were used to identify key genes. Western blotting and real-time quantitative polymerase chain reaction were employed to validate the expression in the same model. Aryl hydrocarbon receptor nuclear translocator-like protein 1 (ARNTL) expression in patients and mice with DKD was assessed using immunohistochemistry staining. ARNTL knockdown in C57BLKS/J mice was established and plasma malonaldehyde, superoxide dismutase, and renal pathology were analyzed. The efficacy of ARNTL knockdown was evaluated using proteomics analysis. Mitochondrial morphology was observed using transmission electron microscopy. ARNTL was screened by bioinformatics analysis and its overexpression verified in patients and mice with DKD. ARNTL knockdown reduced oxidative stress in plasma. Kidney proteomics revealed that ferroptosis was inhibited. The reduction of the classic alteration in mitochondrial morphology associated with ferroptosis was also observed. Gene set enrichment analysis demonstrated that the downregulation of the TGFβ pathway coincided with a decrease in collagen protein and TGFβ1 levels. The ferroptosis-associated gene ARNTL is a potential target for treating DKD. • Significantly increased expression of ferroptosis related gene ARNTL is found in the tubules of obese DKD mice, which may be related to iron metabolism. • ARNTL inhibition alleviates oxidative stress and ferroptosis in DKD. • TGFβ signaling pathway is downregulated after ARNTL knockdown. [ABSTRACT FROM AUTHOR]

While metal additive manufacturing has seen significant growth in recent years, the surfaces produced often need post-processing to improve surface finish, mitigate residual stresses, and remove surface-connected porosity. Laser polishing, by means of remelting a thin layer of the surface, is one post-processing method being investigated for surface finish improvements and other surface enhancements. In this work, the surface morphology and microstructure of laser powder bed fused (L-PBF) stainless-steel 316 L (316 L) before and after laser polishing are characterized by optical microscopy (OM), scanning electron microscopy (SEM), electron back-scatter diffraction (EBSD), and transmission electron microscopy (TEM). In addition, the cross-sectional microhardness of the samples is measured and reported. Additionally, the as-built and laser-polished sample's tensile properties are characterized using uniaxial tension tests. The results indicate that the surface roughness of as-built 316 L (Sa = 4.84 μm) can be substantially reduced through laser polishing (Sa = 0.65 μm). After laser polishing, the average grain diameter is reduced and the proportion of low angle grain boundaries (2°~5°) is increased in the L-PBF 316 L. The maximum sub-surface hardness reaches 262 HV, and both the tensile strength and ductility of 316 L are increased after laser polishing. This enhancement is attributed to thermal cycling stresses, grain refinement, the elimination of surface defects, and dislocation strengthening after laser polishing. [ABSTRACT FROM AUTHOR]

• This study examined the effects of lateral unsaturated flow on shallow landslides triggering in situations of rising water level at the uphill/downhill boundary. • Lateral unsaturated flow is important for slope stability assessment of loamy hillslopes but can be ignored for sandy hillslopes. • The effect of lateral unsaturated flow highly depends on slope angle and the rising rate of uphill boundary water level. • Intensive rainfall may weaken the role of lateral unsaturated flow in activating slope failure. Lateral unsaturated flow was found to contribute little to rainfall-induced shallow landslides, but it can be important when the landslides are triggered under conditions of varying boundary water level. By considering a hillslope with an impermeable bedrock and rising water level at the uphill/downhill boundary, this study explored how lateral unsaturated flow would affect slope stability. Three different Hillslope-Storage Boussinesq models that differ in their treatment of the unsaturated flow were coupled with the same infinite slope stability model to predict and compare the safety factor and instability time. Specific to the situations considered, this study discovered that, despite the inclusion of lateral unsaturated flow effect, the hillslope remains stable when water level at the downhill boundary rises. Under the condition of increasing uphill boundary water level, the consideration of lateral unsaturated flow leads to earlier slope failure for loamy hillslopes with a moderate slope. Also, the lateral unsaturated flow may not induce slope failure for mildly sloping loamy hillslopes and plays an ignorable role when landslides occur fast in very steep hillslopes. By contrast, the lateral unsaturated flow does not affect much the failure of sandy hillslopes. Moreover, when water level at the uphill boundary increases faster, the lateral unsaturated flow exerts a greater influence on initiating slope failure. Further examination shows that intensive rainfall may weaken the effect of lateral unsaturated flow on shallow landslides triggering under the condition of rising uphill boundary water level. [ABSTRACT FROM AUTHOR]

It is common for diabetic kidney disease (DKD) to be complicated by abnormal blood glucose, blood lipids, and blood pressure rhythms. Thus, it is essential to examine diagnostic and treatment plans from the perspective of circadian disruption. This brief review discusses the clinical relevance of circadian rhythms in DKD and how the core clock gene encoding brain and muscle arnt-like protein 1 (BMAL1) functions owing to the importance of circadian rhythm disruption processes, including the excretion of urinary protein and irregular blood pressure, which occur in DKD. Exploring Bmal1 and its potential mechanisms and signaling pathways in DKD following contact with Sirt1 and NF-κB is novel and important. Finally, potential pharmacological and behavioral intervention strategies for DKD circadian rhythm disturbance are outlined. This review aids in unveiling novel, potential molecular targets for DKD based on circadian rhythms. [Display omitted] • DKD has abnormality in albuminuria and hypertension rhythm. • Bmal1 deficiency in the renal correlates with low blood pressure and BMAL1 has obesity paradox. • BMAL1 probably modulates BMAL1/SIRT1/NF-κB pathway to reduce kidney injury in DKD. • Targeted therapeutic approaches for DKD rhythm disorders encompass pharmacological intervention and small-molecule targets. • Regulating daily eating pattern, enhancing sleep quality, and scheduling exercise are also critical. [ABSTRACT FROM AUTHOR]

• A risk prediction for IDH in HD-patients can be an important tool for clinical work. • LightGBM model plays as an interpretable and best-performing model for the task. • IDH-A and IDH-B model can usefully complement each other for risk prediction. Intradialytic hypotension (IDH) is closely associated with adverse clinical outcomes in HD-patients. An IDH predictor model is important for IDH risk screening and clinical decision-making. In this study, we used Machine learning (ML) to develop IDH model for risk prediction in HD patients. 62,227 dialysis sessions were randomly partitioned into training data (70%), test data (20%), and validation data (10%). IDH-A model based on twenty-seven variables was constructed for risk prediction for the next HD treatment. IDH-B model based on ten variables from 64,870 dialysis sessions was developed for risk assessment before each HD treatment. Light Gradient Boosting Machine (LightGBM), Linear Discriminant Analysis, support vector machines, XGBoost, TabNet, and multilayer perceptron were used to develop the predictor model. In IDH-A model, we identified the LightGBM method as the best-performing and interpretable model with C- statistics of 0.82 in Fall30Nadir90 definitions, which was higher than those obtained using the other models (P <0.01). In other IDH standards of Nadir90, Nadir100, Fall20, Fall30, and Fall20Nadir90, the LightGBM method had a performance with C- statistics ranged 0.77 to 0.89. As a complementary application, the LightGBM model in IDH-B model achieved C- statistics of 0.68 in Fall30Nadir90 definitions and 0.69 to 0.78 in the other five IDH standards, which were also higher than the other methods, respectively. Use ML, we identified the LightGBM method as the good-performing and interpretable model. We identified the top variables as the high-risk factors for IDH incident in HD-patient. IDH-A and IDH-B model can usefully complement each other for risk prediction and further facilitate timely intervention through applied into different clinical setting. [Display omitted] [ABSTRACT FROM AUTHOR]

• Spinal astrocytes in Stress-induced gastric mucosal damage in rat. • Astrocytic toxin L-a-aminoadipate (L-AA) prevented the stress-induced gastric damage. • Astrocytes contributed to the stress-induced gastric damage via CX43. Rat restraint water-immersion stress (RWIS) is a compound stress of high intensity and is widely used to study the pathological mechanisms of stress gastric ulcers. The spinal cord, as a part of the central nervous system, plays a dominant role in the gastrointestinal tract, but whether the spinal cord is involved in rat restraint water-immersion stress (RWIS)-induced gastric mucosal damage has not been reported. In this study, we examined the expression of spinal astrocytic glial fibrillary acidic protein (GFAP), neuronal c-Fos, connexin 43 (Cx43), and p-ERK1/2 during RWIS by immunohistochemistry and Western blotting. In addition, we intrathecally injected the astrocytic toxin L-a-aminoadipate (L-AA), gap junction blocker carbenoxolone (CBX), and ERK1/2 signaling pathway inhibitor PD98059 to explore the role of astrocytes in the spinal cord in RWIS-induced gastric mucosal damage and its possible mechanism in rats. The results showed that the expression of GFAP, c-Fos, Cx43, and p-ERK1/2 was significantly elevated in the spinal cord after RWIS. Intrathecal injection of both the astrocyte toxin L-AA and the gap junction blocker CBX significantly attenuated RWIS-induced gastric mucosal damage and decreased the activation of astrocytes and neurons induced in the spinal cord. Meanwhile, the ERK1/2 signaling pathway inhibitor PD98059 significantly inhibited gastric mucosal damage, gastric motility and RWIS-induced activation of spinal cord neurons and astrocytes. These results suggest that spinal astrocytes may regulate the RWIS-induced activation of neurons via CX43 gap junctions and play a critical role in RWIS-induced gastric mucosa damage through the ERK1/2 signaling pathway. [ABSTRACT FROM AUTHOR]

Shape-memory epoxy resins were synthesized using plant oils and cellulose nanocrystals (CNCs). Epoxidized soybean homopolymers (PESBMA) were grafted from CNCs using surface-initiated atom transfer radical polymerization (SI-ATRP). The polymer grafted CNCs were combined with P(ESBMA- co -SBMA) copolymer and cured using anhydride to prepare epoxy resins. Controlling weight fractions of CNCs and ratios of epoxide to anhydride provided tunability over mechanical and thermal properties. The grafted polymer nanocomposites were also compared to simple blends to confirm better properties of the grafted system. Thermo- and chemo-responsive shape memory properties were obtained for these materials. [ABSTRACT FROM AUTHOR]

The refractory high-entropy alloys possess both high melting points and excellent high-temperature properties. As a result, they are expected to become a new generation of high-temperature materials. Along these lines, in this work, selective laser melting (SLM) was used to prepare WMoTaNbV and TiC/WMoTaNbV-based alloys, while the influence of the SLM process parameters on the surface morphology, internal defects distribution and microstructure of the alloy was thoroughly analyzed. On top of that, the long-term high-temperature oxidation behavior of the two alloys at 600°C was studied. The extracted results showed that the process parameters had a serious impact on the surface quality and internal defects of the refractory high-entropy alloys. By optimizing the process parameters, the final surface roughness value of the WMoTaNbV-based alloy was 9.148 μm (Sa). On the contrary, the surface roughness value of the TiC/WMoTaNbV compound was 14.218 μm (Sa). It is also interesting to notice that the incorporation of TiC could significantly reduce the number of cracks within the TiC/WMoTaNbV alloy. Moreover, the WMoTaNbV-based alloy was mainly composed of dendritic structures, while the TiC/WMoTaNbV-based alloy consisted of cellular structures. The main oxidation products of the WMoTaNbV-based alloy were the Ta 16 W 18 O 94 and Nb 14 W 3 O 47 ternary oxidation products. After the TiC particles were added, the Ti-containing oxidation products such as TiO 2 , Ti 2 Nb 10 O 29. etc. within the TiC/WMoTaNbV-based alloy increased significantly, preventing thus effectively the alloy from being seriously oxidized. The cellular structures, carbides and TiO 2 phase are helpful in improving the oxidation resistance of the TiC/WMoTaNbV-based alloy. • The TiC could significantly reduce the number of cracks within the TiC/WMoTaNbV alloy. • The oxidation resistance of the TiC/WMoTaNbV was improved. • The cellular structures, carbides and TiO 2 phase were helpful in improving the oxidation resistance of the TiC/WMoTaNbV alloy. [ABSTRACT FROM AUTHOR]

Abstract: Potassium dihydrogen phosphate (KDP) crystal presents a host of problems to engineers and opticians. Moreover, because of its anisotropic character, a particular crystal orientation and plane wave transmission are required while the machining process is performed. In this study, by applying the principle of the maximized shearing deformed specific energy and the different shearing elastic modulus along different crystal planes and orientations, a theoretical model to calculate the shear angles when cutting KDP crystal was established. Based on this model, the shear angles’ variation regularity under different cutting conditions was obtained. Additionally, the variation regularities of cutting forces and roughness on different crystal planes were discussed. The results indicate that on different crystal planes the average cutting force and roughness as well as their variation amplitude are different. In addition, the calculated results show that rake angle plays an important role on suppression and minimizing material anisotropic character. Furthermore, the ultra-precision turning and milling experiments were conducted, and the theoretical model matched the experiments well within normal operating conditions. [Copyright &y& Elsevier]