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Tunnel boring machines (TBMs) have been increasingly applied in extreme regions such as "Three highs" (high confining pressure, high rock hardness and high quartz content), researchers have introduced laser technology to the TBM field to improve cutting efficiency. The aim of this study is to investigate the effect of laser power, laser moving speed, blade width, distance between the cutter and laser-induced groove (DCLG), and edge angle on rock breakage after coupling the laser with TBM cutter-head, and obtain the optimal combination of these parameters. Two sets of indentation tests were conducted: one with the assistance of laser-induced grooves (LG) based on a L18(37) orthogonal design table; the other was a controlled trial without the laser. The corrected indentation hardness index (CIHI), specific energy (SE) and penetration force were utilized as performance indicators to comprehensively evaluate the experimental results. Additionally, a new method proposed in this paper allowed for accurate measurement of the volume of rock debris, avoiding the difficulties associated with the traditional weighing method, which requires collecting rock fragments caused by rock bursts. Finally, variance analysis, range analysis, and comprehensive evaluation analysis were performed on the three performance indicators. Results show that LG can greatly reduce the penetration force of the cutter and improve cutting efficiency. The primary and secondary factors affecting the rock breaking performance of a laser-assisted cutter are: blade width, DCLG, laser moving speed, laser power and edge angle, and the optimal combination of rock-breaking parameters: The blade width is equal to 3 mm, the DCLG is equal to 5 mm, the laser moving speed is equal to 2 mm/s, the laser power is equal to 20 W, and the edge angle is equal to 12°. [ABSTRACT FROM AUTHOR]

Circulating microRNAs (miRNAs) play a pivotal role in the occurrence and development of acute myocardial infarction (AMI), and precise detection of them holds significant clinical implications. The development of luminol-based luminophores in the field of electrochemiluminescence (ECL) for miRNA detection has been significant, while their effectiveness is hindered by the instability of co-reactant hydrogen peroxide (H2O2). In this work, an iron single-atom catalyst (Fe-PNC) was employed for catalyzing the luminol-O2 ECL system to achieve ultra-sensitive detection of myocardial miRNA. Target miRNA triggers a hybridization chain reaction (HCR), resulting in the generation of a DNA product featuring multiple sticky ends that facilitate the attachment of Fe-PNC probes to the electrode surface. The Fe-PNC catalyst exhibits high promise and efficiency for the oxygen reduction reaction (ORR) in electrochemical energy conversion systems. The resulting ECL biosensor allowed ultrasensitive detection of myocardial miRNA with a low detection limit of 0.42 fM and a wide linear range from 1 fM to 1.0 nM. Additionally, it demonstrates exceptional performance when evaluated using serum samples collected from patients with AMI. This work expands the application of single-atom catalysis in ECL sensing and introduces novel perspectives for utilizing ECL in disease diagnosis. [ABSTRACT FROM AUTHOR]

To understand the macroscopic mechanical characteristics of red sandstone and its microscopic damage mechanism with complex chemical environments, this study investigates the chemical corrosion behavior of red sandstone from Qinghai Province. The research focuses on the effects of Na2SO4 solutions and distilled water at varying pH levels (2, 7, and 12). Using uniaxial compression, nuclear magnetic resonance (NMR), and X-ray diffraction (XRD) analyses, the results demonstrate significant alterations in the mechanical properties of red sandstone. Specifically, there is a 29.20% reduction in the modulus of elasticity in acidic environments, a 24.63% reduction in alkaline environments, a 23.99% reduction in neutral salt solutions, and a 20.25% reduction in distilled water after 40 days. The study provides detailed insights into the role of ion exchange and salt crystallization, revealing that calcium sulfate precipitates form primarily under acidic conditions, but they are also present in two other salt solutions. Crystallization processes occur in all three salt solutions, highlighting the intricate interplay between mineral dissolution, ion exchange, and crystallization. These findings offer a deeper understanding of the water–rock reaction mechanisms affecting red sandstone. The outcomes of this research are crucial for developing strategies to mitigate chemical erosion in geotechnical engineering, especially for infrastructure exposed to industrial pollution and harsh chemical environments. [ABSTRACT FROM AUTHOR]

Hypoxic microenvironments are intricately linked to malignant characteristics of glioblastoma multiforme (GBM). Long non-coding ribonucleic acids (lncRNAs) have been reported to be involved in the progression of GBM and closely associated with hypoxia. Nevertheless, the differential expression profiles as well as functional roles of lncRNAs in GBM cells under hypoxic conditions remain largely obscure. We explored the expression profiles of lncRNAs in hypoxic U87 cells as well as T98G cells using sequencing analysis. The effect of differentially expressed lncRNAs (DElncRNAs) was assessed through bioinformatic analysis. Furthermore, the expression of lncRNAs significantly dysregulated in both U87 and T98G cells was further validated using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Relevant cell functional experiments were also conducted. We used predicted RNA-binding proteins (RBPs) to construct an interaction network via the interaction prediction module. U87 and T98G cells showed dysregulation of 1115 and 597 lncRNAs, respectively. Gene Ontology (GO) analysis indicated that altered lncRNA expression was associated with nucleotide-excision repair and cell metabolism in GBM cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed the association between dysregulated lncRNAs and the Hippo signaling pathway under hypoxia. The dysregulation of six selected lncRNAs (ENST00000371192, uc003tnq.3, ENST00000262952, ENST00000609350, ENST00000610036, and NR_046262) was validated by qRT-PCR. Investigation of lncRNA-microRNA (miRNA)-mRNA networks centered on HIF-1α demonstrated cross-talk between the six validated lncRNAs and 16 related miRNAs. Functional experiments showed the significant inhibition of GBM cell proliferation, invasion, and migration by the knockdown of uc003tnq.3 in vitro. Additionally, uc003tnq.3 was used to construct a comprehensive RBP-transcription factor (TF)-miRNA interaction network. The expression of LncRNAs was dysregulated in GBM cells under hypoxic conditions. The identified six lncRNAs might exert important effect on the development of GBM under hypoxic microenvironment. [ABSTRACT FROM AUTHOR]

Objective: The clinical manifestations of systemic sclerosis (SSc) are highly variable, resulting in varied outcomes and complications. Diverse fibrosis of the skin and internal organs, vasculopathy, and dysregulated immune system lead to poor and varied prognoses in patients with SSc subtypes. Therefore, this study aimed to develop a personalized tool for predicting the prognosis of patients with SSc. Methods: A cohort of 517 patients with SSc were recruited between January 2009 and November 2021 at Xijing Hospital in China, and 266 patients completed the follow-up and performed in the survival analysis. Risk factors for death were identified using Cox survival analysis and random survival forest-based machine-learning methods separately. The consistency index, area under the curve (AUC), and integrated Brier scores were used to compare the predictive performance of the different prognostic models. Results: The results of Cox-based multivariate regression analysis suggested that pulmonary arterial hypertension, digital ulcer, and Modified Rodnan Skin Score (mRSS) were independent risk factors for poor prognosis in patients with SSc and significant risk factors in random survival forest (RSF) surveys. A nomogram was plotted to evaluate the prognostic risk to facilitate clinical assessment; the RSF model had better predictive performance than the Cox model, with 3- and 5-year AUCs of 0.74 and 0.78, respectively. Conclusion: Machine-learning models can help us better understand the prognosis of patients with SSc and comprehensively evaluate the clinical characteristics of each individual. The early identification of the characteristics of high-risk patients can improve the prognosis of those with SSc. Key Points • Regarding predictive performance, the random survival forest model was more effective than the Cox model and had unique advantages in analyzing nonlinear effects and variable importance. • Machine learning using the simple clinical features of patients with systemic sclerosis (SSc) to predict mortality can guide attending physicians, and the early identification of high-risk patients with SSc and referral to experts will assist rheumatologists in monitoring and management planning. [ABSTRACT FROM AUTHOR]

Bone age assessment (BAA) is a crucial task in clinical, forensic, and athletic fields. Since traditional age estimation methods are suffered from potential radiation damage, this study aimed to develop and evaluate a deep learning radiomics method based on multiparametric knee MRI for noninvasive and automatic BAA. This retrospective study enrolled 598 patients (age range,10.00–29.99 years) who underwent MR examinations of the knee joint (T1/T2*/PD-weighted imaging). Three-dimensional convolutional neural networks (3D CNNs) were trained to extract and fuse multimodal and multiscale MRI radiomic features for age estimation and compared to traditional machine learning models based on hand-crafted features. The age estimation error was greater in individuals aged 25–30 years; thus, this method may not be suitable for individuals over 25 years old. In the test set aged 10–25 years (n = 95), the 3D CNN (a fusion of T1WI, T2*WI, and PDWI) demonstrated the lowest mean absolute error of 1.32 ± 1.01 years, which is higher than that of other MRI modalities and the hand-crafted models. In the classification for 12-, 14-, 16-, and 18- year thresholds, accuracies and the areas under the ROC curves were all over 0.91 and 0.96, which is similar to the manual methods. Visualization of important features showed that 3D CNN estimated age by focusing on the epiphyseal plates. The deep learning radiomics method enables non-invasive and automated BAA from multimodal knee MR images. The use of 3D CNN and MRI-based radiomics has the potential to assist radiologists or medicolegists in age estimation. [ABSTRACT FROM AUTHOR]

Background: Sirtuin 5 (SIRT5) is a promising therapeutic target involved in regulating multiple metabolic pathways in cells and organisms. The role of SIRT5 in cancer is currently unclear, and a comprehensive systematic pan-cancer analysis is required to explore its value in diagnosis, prognosis, and immune function. Methods: We investigated the role of SIRT5 in tumorigenesis, diagnosis, prognosis, metabolic pathways, the immune microenvironment, and pan-cancer therapeutic response. Moreover, we explored chemicals affecting the expression of SIRT5 and computed the relationship between SIRT5 and drug sensitivity. Finally, the role of SIRT5 in melanoma was analyzed using a series of experiments in vitro and in vivo. Results: We found that SIRT5 is differentially expressed and shows early diagnostic value in various tumors and that somatic cell copy number alterations and DNA methylation contribute to its aberrant expression. SIRT5 expression correlates with clinical features. Besides, it is negatively (positively) correlated with several metabolic pathways and positively (negatively) correlated with several important metastasis-related and immune-related pathways. High SIRT5 expression predicts poor (or good) prognosis in various tumors and can affect drug sensitivity. We also demonstrated that SIRT5 expression significantly correlates with immunomodulator-associated molecules, lymphocyte subpopulation infiltration, and immunotherapeutic response biomarkers. In addition, we showed that SIRT5 is differentially expressed in immunotherapy cohorts. In addition, we explored various chemicals that may affect SIRT5 expression. In conclusion, we demonstrated that SIRT5 is a key pathogenic gene that promotes melanoma progression. Conclusion: Our study provides a systematic analysis of SIRT5 and its regulatory genes. SIRT5 has excellent diagnostic and prognostic capabilities for many cancers. This may remodel the tumor microenvironment. The potential of SIRT5-based cancer therapies is emphasized and helps predict the response to immunotherapy. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) have attracted considerable attention due to their unique structures and excellent catalytic performance, especially in the area of catalysis science and energy conversion and storage. In recent years, SACs have emerged as a new type of sensing material for constructing electrochemical sensors (ECSs), presenting excellent sensitivity, selectivity, and stability. Herein, we review the recent advances of SACs in electrochemical sensing and discuss the status quo of current SAC-based ECSs. Specifically, the fundamentals of SAC-based ECSs are outlined, including the involved central metal atoms and various supports of SACs in this field, the detection mechanisms, and improving strategies of SAC-based ECSs. Moreover, the important applications of SAC-based ECSs are listed and classified, covering the detection of reactive oxygen and nitrogen species, environmental pollutants, disease biomarkers, and pharmaceuticals. Last, based on abundant reported cases, the current conundrums of SAC-based ECSs are summarized, and the prediction of their future developing trends is also put forward. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Humic acid–based carbon dots (HACDs) have excellent properties and are widely used in environmental detection, bioimaging, and optoelectronic materials. Herein, we investigated the structure–activity relationship between the morphology and optical properties of HACDs, and reported on a novel strategy for metronidazole (MNZ) and ornidazole (ONZ) sensing in multiple real samples. It was found that the average particle size decreased from 3.28 to 2.44 nm, optimal emission wavelength was blue-shifted from 500 to 440 nm, and the quantum yield (QY) improved from 5 to 23% with the temperature increasing from 110 to 400 °C. Under the oxidation of hydrogen peroxide (H2O2) and potassium permanganate (KMnO4), the UV–vis spectra of HACD aqueous solution showed time-dependent behavior, and the fluorescence emission of HACDs achieved spectrally tunable multi-color luminescence in the temporal dimension. The surface of HACDs contained a large number of hydroxyl (–OH) and carboxyl (–COOH) fluorophores, resulting in excellent pH sensing. Meanwhile, the synthesized HACDs revealed sensitive response to MNZ and ONZ with the limit of detection (LOD) of 60 nM and 50 nM in aqueous solutions, which had also been successfully applied in various actual samples such as lake water, honey, eggs, and milk with satisfactory results because of the inner filter effect (IFE). Our research is advantageous to enhance the potential applications of HACDs in advanced analytical systems. [ABSTRACT FROM AUTHOR]

Purpose: Metabolic and bariatric surgery (MBS) can exert effective function on glycemic control. The present study aimed to estimate the risk of MACE among obese patients with diabetes after MBS. Materials and Methods: Systematic search of PubMed, Embase, Medline, and Web of Science was performed for studies published before 20th February 2023. The odds ratio (OR) corresponding to the 95% confidence interval (95% CI) was used to assess the outcome. The statistical heterogeneity among studies was assessed with the Q-test and I2 statistics. Results: Fifteen cohort studies with 122,361 obese patients with diabetes were available for analysis. Our meta-analysis found significantly decreased morbidity and mortality of MACE (OR = 0.65, 95% CI = 0.59–0.72, I2 = 62.8% for morbidity, OR = 0.49, 95% CI = 0.36–0.67, I2 = 68.7% for mortality). Subgroup analysis revealed MBS decreased cerebrovascular disease, coronary artery disease, atrial fibrillation, heart failure, myocardial infarction, and stroke risk. Conclusion: Our meta-analysis indicated that MBS for obese patients with diabetes is beneficial to decreasing MACE risk. Moreover, further studies estimating the functional effect may eventually provide a better and comprehensive understanding of the effect on different populations. [ABSTRACT FROM AUTHOR]

Long-term variations in population structure, growth, mortality, length at median sexual maturity, and exploitation rate of threadfin bream (Nemipterus virgatus) are reported based on bottom trawl survey data collected during 1960–2012 in the Beibu Gulf, South China Sea. Laboratory-based analyses were conducted on 16 791 individuals collected quarterly in eight different sampling years. Average body length, estimated asymptotic length, and percentage of large individuals have decreased significantly with the growth of marine catch and fishing power, indicating individual miniaturization of this fish species. Estimated exploitation rates indicate that the N. virgatus stock in the Beibu Gulf was moderately exploited in 1960 and 1962 and overexploited after 1992. This stock was taking a good turn in status in 2012, with the lowest exploitation rate since 1992 and ceased downward trend in length indexes. These results suggest that management measures to reduce fishing pressure may have a positive influence on the biological characteristics of this commercial fish species. Biological characteristics of most commercial fish species have phenotypic plasticity and might change over years in response to fisheries management. Therefore, attentions should be paid on variations in fish biological characteristics, when evaluating the effectiveness of current measures to control the total catch for all fisheries. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of the company's selection and configuration of automobile constant velocity universal joint, and to reduce the enterprise's internal production costs, a method for the development and design of automobile constant velocity universal joint was proposed based on mass customization in this study. By constructing the master model of constant velocity universal joint components, modular development of products of the same family with similar functional structures was carried out, and the configuration design and variant design of universal joint components are completed. Use CATIA to design a digital platform for automotive constant velocity joint that quickly responds to customer needs, and perform fatigue life experiments on the designed constant velocity joint. The results show that the digital platform of constant velocity universal joint can more efficiently mass-produce customized products. [ABSTRACT FROM AUTHOR]

Purpose: Heavy metals and metalloids are recognized as environmental threats, which are considered highly toxic and carcinogenic. Epidemiologically, their association with leukemia is under debate. We aim to clarify the association between the heavy metal(loid)s in serum and leukemia via a systematic review and meta-analysis. Methods: We searched PubMed, Embase, Google Scholar, and CNKI (China National Knowledge Infrastructure) databases for all related articles. The standardized mean difference and its 95% confidence interval was used to evaluate the association of leukemia with heavy metal(loid)s in serum. The statistical heterogeneity among studies was assessed with the Q-test and I2 statistics. Results: Among 4,119 articles related to metal(loid)s and leukemia, 21 studies met our inclusion criteria, which are all cross-sectional studies. These 21 studies involved 1,316 cases and 1,310 controls, based on which we evaluate the association of heavy metals/metalloids in serum with leukemia. Our results indicated positive differences for serum chromium, nickel, and mercury in leukemia patients, while a negative difference for serum manganese in acute lymphocytic leukemia (ALL). Conclusion: Our results suggested an elevated trend of serum chromium, nickel, and mercury concentrations in leukemia patients while descending trend of serum manganese concentration in ALL patients. The result of sensitivity analysis between lead, cadmium, and leukemia and publication bias of association between chromium and leukemia also needed attention. Future research work may focus on the dose-response relationship between any of these elements and the leukemia risks, and further elucidation of how these elements are related to leukemia may shed light on the prevention and treatment of leukemia. [ABSTRACT FROM AUTHOR]

The development of a battery management algorithm is highly dependent on high-quality battery operation data, especially the data in extreme conditions such as low temperatures. The data in faults are also essential for failure and safety management research. This study developed a battery big data platform to realize vehicle operation, energy interaction and data management. First, we developed an electric vehicle with vehicle navigation and position detection and designed an environmental cabin that allows the vehicle to operate autonomously. Second, charging and heating systems based on wireless energy transfer were developed and equipped on the vehicle to investigate optimal charging and heating methods of the batteries in the vehicle. Third, the data transmission network was designed, a real-time monitoring interface was developed, and the self-developed battery management system was used to measure, collect, upload, and store battery operation data in real time. Finally, experimental validation was performed on the platform. Results demonstrate the efficiency and reliability of the platform. Battery state of charge estimation is used as an example to illustrate the availability of battery operation data. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Regression testing is required to assure the quality of each iteration of microservice systems. Test case selection is one of main techniques to optimize regression testing. Existing techniques mainly involve artifacts acquisition, processing and maintenance, thus hard to apply in microservice regression testing since it is difficult to obtain and process required artifacts from multiple development teams, which is normal in cases of microservice systems. This paper proposes a novel approach, namely MRTS-BP, which takes API gateway logs instead of artifacts as inputs. By mining service dependencies from API gateway logs, MRTS-BP analyzes service change impacts based on a propagation calculation, and selects test cases affected by changes based on impact degree values. To evaluate the effectiveness of MRTS-BP, empirical studies based on four real deployed systems are presented. Retest-all strategy and a regression testing selection approach based on control flow graphs called RTS-CFG are compared with MRTS-BP. The results show that, MRTS-BP can significantly reduce both the number of test cases and overall time cost while maintaining the fault detection capability of selected test suite, and that MRTS-BP can save more time cost than RTS-CFG with the similar safety and precision. [ABSTRACT FROM AUTHOR]

A bidirectional in vitro brain–computer interface (BCI) directly connects isolated brain cells with the surrounding environment, reads neural signals and inputs modulatory instructions. As a noninvasive BCI, it has clear advantages in understanding and exploiting advanced brain function due to the simplified structure and high controllability of ex vivo neural networks. However, the core of ex vivo BCIs, microelectrode arrays (MEAs), urgently need improvements in the strength of signal detection, precision of neural modulation and biocompatibility. Notably, nanomaterial-based MEAs cater to all the requirements by converging the multilevel neural signals and simultaneously applying stimuli at an excellent spatiotemporal resolution, as well as supporting long-term cultivation of neurons. This is enabled by the advantageous electrochemical characteristics of nanomaterials, such as their active atomic reactivity and outstanding charge conduction efficiency, improving the performance of MEAs. Here, we review the fabrication of nanomaterial-based MEAs applied to bidirectional in vitro BCIs from an interdisciplinary perspective. We also consider the decoding and coding of neural activity through the interface and highlight the various usages of MEAs coupled with the dissociated neural cultures to benefit future developments of BCIs. [ABSTRACT FROM AUTHOR]

Development of inexpensive and environmentally friendly chemical sensors can help improve the global ecological environment and reduce pollutant emissions. In this work, asphaltene of coal liquefaction by-product was employed as the carbon source to fabricate carbon dots (CDs) by straightforward microwave radiation. The asphaltene-based CDs gave out blue emission under UV light excitation. Interestingly, the CDs are highly lipophilic because of its carbonized structure and insufficient hydrophilic groups. Based on these findings, an outstanding fluorescent sensor for 2,4,6-trinitrophenol (TNP) was developed by loading asphaltene-based CDs into polymeric micelles. The micelle formed by nonionic tri-block copolymers exhibited a hydrophobic inner cavity and hydrophilic surface. Due to the protection of the micelles, the emission of asphaltene-based CDs was enhanced by 2.89 times. But the fluorescence was significantly quenched by TNP through energy transfer and electron transfer mechanism, showing high sensitivity to TNP with a detection limit of 0.21 μM. The findings presented here provide a green method to synthesize fluorescent CDs and a promising strategy to design fluorescent probes. [ABSTRACT FROM AUTHOR]

Rock cutting by tunnel boring machine (TBM) disc cutters is usually simplified as an indentation-type or linear-cutting process. It is inconsistent with the actual rock-breaking motion of disc cutters and therefore impedes to some extent the research on the rock-breaking mechanism, wear mechanism and design theory. In order to evaluate the kinematic law of points on cutter rings within the rock–cutter contact area (hereinafter referred to as rock-breaking points), the ring is divided into a series of infinitesimal circle-shaped cutting elements. Each of them could be determined by its coordinate position in the axial direction of the disc cutter. After that, according to the installation parameters of roller disc cutters mounted on the cutterhead and spatial geometric features of the cutters, the spatial kinematic model of any cutting element from a given cutter is proposed, and then the functional relationships between three-dimensional displacement components of the rock-breaking points and geometric parameters of the disc cutter are established. In order to demonstrate that the mentioned model has great application prospects in TBM industry, the cutting load prediction model of the disc cutter is derived from the kinematic model by introducing the linear spring model. Finally, by comparing with experimental data obtained from the rotary cutting tests, it can be seen that the prediction model built in this paper can better reflect the cutting load characteristics of TBM disc cutters with different installation parameters. [ABSTRACT FROM AUTHOR]

Alcohols are ubiquitous in chemistry and are native functionalities in many natural products and bioactive molecules. As such, a strategy that utilizes hydroxy-containing compounds to develop bond disconnection and bond formation process would achieve molecular diversity. Herein we utilize bench-stable N-alkoxyphthalimides prepared from alcohols to couple with glycine derivatives via radical process under visible light irradiation, providing a variety of unnatural amino acid (UAA) and peptide derivatives. The approach allows to rapidly deconstruct molecular complexity via β-fragmentation such as saclareolide, β-pinene and camphor and provides products with unique scaffolds, which show inhibition toward the pathogenic fungi growth. Transformations of alcohols, which are ubiquitous in chemistry and are native functionalities in many natural products and bioactive molecules, are cornerstones of organic synthesis. Here the authors describe photocatalyzed cross-couplings of activated alcohols with α-amino acids, providing a direct approach for a variety of unnatural amino acids. [ABSTRACT FROM AUTHOR]

Visual question answering is a complex multimodal task involving images and text, with broad application prospects in human–computer interaction and medical assistance. Therefore, how to deal with the feature interaction and multimodal feature fusion between the critical regions in the image and the keywords in the question is an important issue. To this end, we propose a neural network based on the encoder–decoder structure of the transformer architecture. Specifically, in the encoder, we use multi-head self-attention to mine word–word connections within question features and stack multiple layers of attention to obtain multi-level question features. We propose a mutual attention module to perform information exchange between modalities for better question features and image features representation on the decoder side. Besides, we connect the encoder and decoder in a meshed manner, perform mutual attention operations with multi-level question features, and aggregate information in an adaptive way. We propose a multi-scale fusion module in the fusion stage, which utilizes feature information at different scales to complete modal fusion. We test and validate the model effectiveness on VQA v1 and VQA v2 datasets. Our model achieves better results than state-of-the-art methods. [ABSTRACT FROM AUTHOR]

This document is a correction to an article titled "Perfluoroalkyl and polyfluoroalkyl substances and cancer risk: results from a dose-response meta-analysis." The correction states that the title of the article was incorrectly given as "Perfluoroalkyl and polyfluoroalkyl substances and Cancer Risk: Results from A Does-response Meta-analysis" and should have been "Perfluoroalkyl and polyfluoroalkyl substances and Cancer Risk: Results from A Dose-response Meta-analysis." The correction has been made to the original article. The authors of the article are Jingxuan Yang, Kui Zhang, and Jingyi Shi. The correction does not provide any additional information or findings. [Extracted from the article]

Regression testing is required in each development iteration of microservice systems. Test case prioritization, which improves the fault detection rate by optimizing the execution order of test cases, is one of the main techniques to optimize regression testing. Existing test case prioritization techniques mainly rely on artifacts such as codes and system models, which are limited to microservice systems with service autonomy, development method diversity, and large service scale. This paper proposes a test case prioritization approach based on service ranking referred to as TCP-SR. TCP-SR ranks the services based on API gateway logs. The weights of test cases are calculated with the result of service ranking, which could be used to order test cases with single-objective and multi-objective strategies. To evaluate the effectiveness of TCP-SR, the empirical study based on four microservice systems is presented. The results show that the fault detection rate of TCP-SR is almost twice as high as that of the random prioritization technique, and almost the same as the prioritization technique based on WS-BPEL but requires much less prioritization time cost. [ABSTRACT FROM AUTHOR]

Forensic identification of human remains is crucial for legal, humanitarian, and civil reasons. Wide heterogeneity in sphenoid sinus morphology can be used for personal identification. This study aimed to propose a new protocol for personal identification based on three-dimensional (3D) reconstruction of sphenoid sinus CT images using Iterative Closest Point (ICP) algorithm. Seven hundred thirty-two patients which consisted of 348 females and 384 males were retrospectively included. The study sample includes 732 previous images as a source point set and 743 later ones as a scene target set. The sphenoid sinus computed tomography (CT) images were processed on a workstation (Dolphin imaging) to obtain 3D images and stored as a file format of Stereo lithography (.STL). Then, a Python library vtkplotter was used to transform the STL format to PLY format, which was adapted to Point Cloud Library (PCL). The ICP algorithm was used for point clouds matching. The metric Rank-N recognition rate was used for evaluation. The scene target set of 743 individuals was compared with the source point set of 732 individual models and achieved Rank-1 accuracy of 96.24%, Rank-2 accuracy of 99.73%, and Rank-3 accuracy of 100%. Our results indicated that the 3D point cloud registration of sphenoid sinuses was useful for assessing personal identification in forensic contexts. [ABSTRACT FROM AUTHOR]

The adversarial patch is a practical and effective method that modifies a small region on an image, making DNNs fail to classify. Existing empirical defenses against adversarial patch attacks lack theoretical analysis and are vulnerable to adaptive attacks. To overcome such shortcomings, certified defenses that provide a guaranteed classification performance in the face of strong unknown adversarial attacks are proposed. However, on the one hand, existing certified defenses either have low clean accuracy or need specified architecture, which is not robust enough. On the other hand, they can only provide provable accuracy but ignore the relationship to the number of perturbations. In this paper, we propose a certified defense against patch attacks that provides both the provable radius and high classification accuracy. By adding Gaussian noises only on the patch region with a mask, we prove that a stronger certificate with high confidence can be achieved by randomized smoothing. Furthermore, we design a practical scheme based on joint voting to find the patch with a high probability and certify it effectively. Our defense achieves 86.4% clean accuracy and 71.8% certified accuracy on CIFAR-10 exceeding the maximum 60% certified accuracy of existing methods. The clean accuracy of 67.8% and the certified accuracy of 53.6% on ImageNet are better than the state-of-the-art method, whose certified accuracy is 26%. [ABSTRACT FROM AUTHOR]

Considering that conventional experiment methods are time-consuming, laborious and expensive, on the premise of understanding the rock fragmentation mechanism of disc cutter cutting and laser drilling respectively, a novel simulation modeling method of rock breaking of tunnel boring machines (TBM) disc cutters assisted with the laser is proposed. The method includes two-step modeling features: 1) in the first step, a finite element model of laser drilling is established in ANSYS, and then the morphology of a single hole and fissures can be predicted using the birth and death element method; 2) in the second step, a rock finite element model with multiple holes is reconstructed in HyperMesh, where the holes with a given hole spacing n have the same shape as the first step; then, ANSYS/LS-DYNA is used to carry out the simulation analysis, thereby indirectly simulating rock breaking process of TBM cutters assisted with laser. Finally, to demonstrate the applicability of the method, a simulation case study is carried out and the obtained values such as cutting force, the amount of rock breaking, and specific energy consumption are according with theoretical expectations. It can be seen that this paper provides an economical and feasible solution for the study of laser-assisted rock breaking. [ABSTRACT FROM AUTHOR]

Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19), with macrophages as one of the main cell types involved. It is urgent to understand the interactions among permissive cells, macrophages, and the SARS-CoV-2 virus, thereby offering important insights into effective therapeutic strategies. Here, we establish a lung and macrophage co-culture system derived from human pluripotent stem cells (hPSCs), modeling the host-pathogen interaction in SARS-CoV-2 infection. We find that both classically polarized macrophages (M1) and alternatively polarized macrophages (M2) have inhibitory effects on SARS-CoV-2 infection. However, M1 and non-activated (M0) macrophages, but not M2 macrophages, significantly up-regulate inflammatory factors upon viral infection. Moreover, M1 macrophages suppress the growth and enhance apoptosis of lung cells. Inhibition of viral entry using an ACE2 blocking antibody substantially enhances the activity of M2 macrophages. Our studies indicate differential immune response patterns in distinct macrophage phenotypes, which could lead to a range of COVID-19 disease severity. Model systems to study SARS-CoV-2 infection are required to better understand the immune response. Here the authors use a lung and macrophage co-culture system by differentiation of human pluripotent stem cells to better understand the phenotype and gene expression changes in host lung cells and macrophages after SARS-CoV-2 infection in vitro. [ABSTRACT FROM AUTHOR]

Introduction: The diagnosis and treatment of osteoporosis, a frequent age-related metabolic bone disorder, remain incomprehensive and challenging. The potential regulatory role of lncRNA XIST and sphingosine kinase 1 (SPHK1) pathway need experimental investigations. Materials and methods: RAW264.7 cells and BMMs were obtained for in vitro studies and 30 ng/mL RANKL was implemented for induction of osteoclast differentiation. The suppressing of lncRNA XIST, SPHK1 and fused in sarcoma (FUS) was achieved using small hairpin RNA, while overexpression of XIST and FUS was constructed by pcDNA3.1 vector system. Tartrate-resistant acid phosphatase (TRAP) staining was used for observation of formation of osteoclasts. RNA-pulldown analysis and RNA binding protein immunoprecipitation (RIP) was implemented for measuring mRNA and protein interactions. RT-qPCR was conducted to determining mRNA expression, whereas ELISA and Western blotting assay was performed for monitoring protein expression. Results: RANKL induced osteoclast differentiation and upregulated expression of osteoclastogenesis-related genes that included NFATc1, CTSK, TRAP and SPHK1 and the level of lncRNA XIST in both RAW264.7 cells and BMMs. However, knockdown of lncRNA XIST or suppressing SPHK1 significantly reserved the effects of RANKL. LncRNA XIST was further demonstrated to be interacted with FUS and increased the stability of SPHK1, indicating its ability in promoting osteoclast differentiation through SPHK1/S1P/ERK signaling pathway. Conclusion: LncRNA XIST promoted osteoclast differentiation via interacting with FUS and upregulating SPHK1/S1P/ERK pathway. [ABSTRACT FROM AUTHOR]

Color-tunable luminescent polymer composite materials are desired for applications in light-emitting diodes. Herein, we directly use commercial humic acid as precursor to fabricate carbon dots by one-step hydrothermal method in formic acid and hydrogen peroxide solution. It is found that the size distribution of synthesized carbon dots ranges from 2 to 5 nm, and the carbon dots display concentration-dependent multi-color luminescence in formic acid, N,N-dimethylformamide and deionized water under 365-nm UV light, separately. The quantum yield of the as-made carbon dots with broad color tunability (445–587 nm) in formic acid is about 20% at 0.3125 mg/ml. Furthermore, by adjusting the concentration of carbon dots in polyvinyl alcohol, the composite films emit blue, cyan and light yellow fluorescence and the Commission Internationale de L'Eclairage color coordinates vary from (0.19, 0.23), through (0.25, 0.35) to (0.29, 0.40) at the content of CDs 3, 5 and 7 wt.% under the excitation of 365 nm, respectively. Meanwhile, the transmittance of the composite film at 5 wt.% is maintained at 81.8 to 87.2% of the pure polyvinyl alcohol film at 550 nm wavelength. This work provides an innovative, simple and efficient way to prepare concentration-dependent polychromatic carbon dots composite films, and the obtained multi-color light-emitting composites have a wide range of photoluminescence spectra, covering most of the visible light range, which opens up the possibility of applying these materials in the fields of optoelectronic materials. An innovative, simple and efficient way to fabricate concentration-dependent multi-color CDs/PVA composite films, which promote the application of CDs in the fields of optoelectronic materials. [ABSTRACT FROM AUTHOR]

The effect of homogenization treatment on the corrosion behavior and corrosion mechanism of Mg-Y alloys in 3.5 wt% NaCl solution was investigated by electrochemical characterization, immersion testing and SEM observations. The diffusion kinetics model of Mg-Y alloy was established, and the homogenization system was determined. With increasing of homogenization temperature and time, the Mg24Y5 phase gradually decreased, which increased the self-corrosion potential and the high-frequency arc radius. The corrosion resistance of the five alloys could be given as follow: Mg-0.25Y < Mg-8Y < Mg-15Y < Mg-5Y < Mg-2.5Y. The Mg- (0.25, 2.5 and 5) Y show localized corrosion in a wide range and small depth, while Mg- (8 and 15) Y showed localized corrosion in a smaller range and larger depth. [ABSTRACT FROM AUTHOR]

Most fisheries in China do not have maximum sustainable yield (MSY) estimates due to limited and poor data. Therefore, finding a common method to estimate MSY or total allowable catch (TAC) for fishery management is necessary. MSYs of three important fisheries in the East China Sea were evaluated through a catch-based model. Estimates for intrinsic rate of increase (r) and five levels of process error were considered. Results showed hairtail Trichiurus japonicas (Temminck and Schlegel) and small yellow croaker Larimichthys polyactis (Bleeker) fisheries experienced overfishing from the mid-1990s to the early 2000s, and the suggested TACs were 55.8×10 t and 9.06×10 t, respectively. Decades of overfishing in wintering and spawning grounds of large yellow croaker Larimichthys crocea (Richardson) caused the fishery's collapse in the 1980s, and it has not recovered until today. The Catch-MSY model generated similar estimated MSYs with other methods and may be a useful choice for the assessment of regional stocks in China. [ABSTRACT FROM AUTHOR]

A smartphone-based dual-wavelength digital imaging platform containing red (539–695 nm) and blue (389–511 nm) band-pass filters was developed for point-of-care (POC) testing of alkaline phosphatase (ALP) activity. The platform was based on dual-emitting fluorescent nanohybrids (AuNC@NAN), the ratiometric probe, which had a fluorescence "on-off-on-off" response. The probe comprised red-emitting gold nanoclusters (AuNCs) acting as the signal report units and blue-emitting N-(2-aminoethyl-1,8-naphthalimide) (NAN) acting as an internal reference. The different responses of the ratiometric probes resulted in a continuous color-multiplexing change from pink-red to dark-purple upon exposure to ALP. The dual-wavelength digital imaging platform was employed to acquire images of AuNC or NAN fluorescence signals without the influence of background light. Unlike the classical one-time digital imaging mode, the accurate red (R) and blue (B) channel values of the generated images can help to directly judge or eliminate the disturbance from unavoidable interfering factors. The R/B values were successfully employed for determining the ALP activity at a range 2.0 to 35.0 mU·mL−1 with the detection limit of 1.04 mU·mL−1. Such sensing imaging platform is also successful in determining ALP activity in human serum with 94.9–105% recoveries and relative standard deviation in the range 4.2–5.6%. [ABSTRACT FROM AUTHOR]

Microencapsulated ammonium polyphosphate (SiAPP) was prepared by sol-gel method with gel-silica as the shell material. And also, SiAPP was characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM), which confirmed the successfully fabrication of SiAPP. Furthermore, 30 php (parts per hundreds of polyol) SiAPP was introduced to prepare rigid polyurethane foam/microcapsulated ammonium polyphosphate composites (RPUF/SiAPP30). Flame retardancy, water resistance, physical properties and thermal stability of RPUF/SiAPP composites were compared with virgin RPUF and RPUF/APP composites. The results showed that RPUF/SiAPP30 which possessed excellent flame retardancy. Even after being immersed in water for 15 days, the underwriters laboratories vertical burning test (UL-94) of RPUF/SiAPP30 could pass V-1 rating with the limiting oxygen index (LOI) of 21.8 vol%, which was better that of RPUF/APP30. Compressive strength of RPUF/SiAPP30 was 0.292 MPa, which was 12.3% higher that of RPUF/APP30. SEM and Raman spectra confirmed that RPUF/SiAPP30 possessed more compact char residue with higher thermal resistance, which could inhibit mass and heat transmission in combustion. Consequently, a possible gas-solid flame-retardant mechanism of RPUF/SiAPP composite was proposed. Highlights: Gel-silica microencapsulated ammonium polyphosphate (SiAPP) was introduced into RPUF composites in the first time. SiAPP could significantly enhance water resistance, mechanical properties as well as flame retardancy of RPUF/SiAPP composites. RPUF/ SIAPP has excellent thermal insulation properties. [ABSTRACT FROM AUTHOR]

Background: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent organic pollutants in the environment. While some studies suggest that PFASs may contribute to cancer development, the link between PFAS exposure and cancer risk remains debated.This dose-response meta-analysis explores the relationship between PFASs and cancer. It employs odds ratio (OR) and standardized mean difference (SMD), along with their 95% confidence interval (CI), to assess the effects of PFASs on cancer risk. Relevant studies were sourced from Web of Science, PubMed, Embase, Medline, and CNKI databases. The dose-response relationship was assessed by the fixed-effects model and least-squares regression.Forty studies, involving a total of 748,188 participants, were included in this meta-analysis. Out of these, 13 studies were specifically analyzed for the dose-response relationship. Findings revealed that exposure to PFASs, especially PFDA, significantly raises the risk of genitourinary cancers, and PFDA exposure shows a dose-dependent increase in overall and breast cancer risk. Additionally, PFOS exposure is associated with an increased cancer risk, and elevated PFOA levels were significantly observed in breast cancer patients.The findings suggest that PFAS exposure is a potential cancer risk factor, with the carcinogenic potential of PFDA being dose-dependent.Methods: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent organic pollutants in the environment. While some studies suggest that PFASs may contribute to cancer development, the link between PFAS exposure and cancer risk remains debated.This dose-response meta-analysis explores the relationship between PFASs and cancer. It employs odds ratio (OR) and standardized mean difference (SMD), along with their 95% confidence interval (CI), to assess the effects of PFASs on cancer risk. Relevant studies were sourced from Web of Science, PubMed, Embase, Medline, and CNKI databases. The dose-response relationship was assessed by the fixed-effects model and least-squares regression.Forty studies, involving a total of 748,188 participants, were included in this meta-analysis. Out of these, 13 studies were specifically analyzed for the dose-response relationship. Findings revealed that exposure to PFASs, especially PFDA, significantly raises the risk of genitourinary cancers, and PFDA exposure shows a dose-dependent increase in overall and breast cancer risk. Additionally, PFOS exposure is associated with an increased cancer risk, and elevated PFOA levels were significantly observed in breast cancer patients.The findings suggest that PFAS exposure is a potential cancer risk factor, with the carcinogenic potential of PFDA being dose-dependent.Results: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent organic pollutants in the environment. While some studies suggest that PFASs may contribute to cancer development, the link between PFAS exposure and cancer risk remains debated.This dose-response meta-analysis explores the relationship between PFASs and cancer. It employs odds ratio (OR) and standardized mean difference (SMD), along with their 95% confidence interval (CI), to assess the effects of PFASs on cancer risk. Relevant studies were sourced from Web of Science, PubMed, Embase, Medline, and CNKI databases. The dose-response relationship was assessed by the fixed-effects model and least-squares regression.Forty studies, involving a total of 748,188 participants, were included in this meta-analysis. Out of these, 13 studies were specifically analyzed for the dose-response relationship. Findings revealed that exposure to PFASs, especially PFDA, significantly raises the risk of genitourinary cancers, and PFDA exposure shows a dose-dependent increase in overall and breast cancer risk. Additionally, PFOS exposure is associated with an increased cancer risk, and elevated PFOA levels were significantly observed in breast cancer patients.The findings suggest that PFAS exposure is a potential cancer risk factor, with the carcinogenic potential of PFDA being dose-dependent.Conclusions: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent organic pollutants in the environment. While some studies suggest that PFASs may contribute to cancer development, the link between PFAS exposure and cancer risk remains debated.This dose-response meta-analysis explores the relationship between PFASs and cancer. It employs odds ratio (OR) and standardized mean difference (SMD), along with their 95% confidence interval (CI), to assess the effects of PFASs on cancer risk. Relevant studies were sourced from Web of Science, PubMed, Embase, Medline, and CNKI databases. The dose-response relationship was assessed by the fixed-effects model and least-squares regression.Forty studies, involving a total of 748,188 participants, were included in this meta-analysis. Out of these, 13 studies were specifically analyzed for the dose-response relationship. Findings revealed that exposure to PFASs, especially PFDA, significantly raises the risk of genitourinary cancers, and PFDA exposure shows a dose-dependent increase in overall and breast cancer risk. Additionally, PFOS exposure is associated with an increased cancer risk, and elevated PFOA levels were significantly observed in breast cancer patients.The findings suggest that PFAS exposure is a potential cancer risk factor, with the carcinogenic potential of PFDA being dose-dependent. [ABSTRACT FROM AUTHOR]

Objective: To explore the mechanism of Pi (Spleen)-deficiency-induced functional diarrhea (FD) model rats treated by Shenling Baizhu Powder (参苓白术散, SBP). Methods: Thirty male Sprague-Dawley rats were randomly divided into 5 groups including control, model, low-, medium-, and high-dose SBP groups (SBPLDG, SBPMDG, SBPHDG), 6 rats in each group, respectively. Pi-deficiency-induced FD rats model was developed through Radix et Rhizoma Rhei gavage for 7 days. After modeling, the rats were treated with 3 doses of SBP [0.93, 1.86, and 3.72 g/(kg·d)], and the rats in the control and model groups were given pure water for 7 days. The diarrhea index was calculated. On the 7th and 14th days, the traveled distance of rat was measured by the open field test. Serum D-xylose content was determined by the phloroglucinol method and interleukin (IL)-10 and IL-17 levels were measured using an enzyme-linked immunosorbent assay kit. The content of Treg cells was determined by flow cytometry. Results: Compared with the control group, the diarrhea index and IL-17 level in the model group were significantly higher and the total exercise distance and D-xylose content significantly decreased (P>0.05). The expression of IL-10 in the SBPHDG group was significantly up-regulated, and serum D-xylose level and Treg cells increased significantly compared with the model group (P>0.05). Conclusion: High-dose SBP exhibited ameliorating effects against Pi-deficiency induced FD, which might be attributed to its modulations on intestinal absorption function as well as adaptive immunity in mesenteric lymph nodes of rat. [ABSTRACT FROM AUTHOR]

The cooling gradient of Mg–3Zn–1Ca–0.5Sr alloy in cast ingots under different cooling methods (air cooling, warm-water cooling and ice–water-mixture cooling) was examined and the effect of cooling rate on the structure and corrosion properties was studied. The microstructure of the alloy was composed of α-Mg, Ca2Mg6Zn3 and Mg17Sr2 phases. As the solidification cooling rate increased, the grain was refined, Zn and Sr were less segregated, the distributions of Zn and Sr were more uniform, and corrosion rate was found to first increase and then decrease; this contradicts the findings of recent research. With cooling rate increasing, the number of corroded microcouples comprising second phase and α-Mg increases. More α-Mg participates in corrosion, leading to a layered and deep corrosion pit and an increased corrosion rate. However, as the microstructure became sufficiently dense, the corroded structure protected the deep α-Mg from participating in corrosion, thus reducing the corrosion rate. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are a new type of porous crystal materials that have been widely used in various fields. Owing to their adjustable porous structure, MOF photocatalysts with high catalytic activity have become a research hotspot. In this study, NH2-MIL-125/CoSx samples were investigated as a novel visible light-responsive catalyst for the removal of organic dye. The NH2-MIL-125/CoSx-20 composites showed the best photodegradation efficiency, where photodegradation of the rhodamine B reached 95.4% in 45 min. CoSx was able to effectively extend the wavelength absorption range of NH2-MIL-125 and effectively separate the photogenerated electrons and holes and that could lead to the improved photocatalytic performance of the composites. The reactive superoxide radical (·O2−) was identified as the main active species using reactive species capture experiments, and a reasonable photocatalytic mechanism was proposed. This paper is intended to guide the development of organic–inorganic hybrid materials for environmental remediation. [ABSTRACT FROM AUTHOR]

Purpose: To assess the performance of PET vascular activity score (PETVAS) in comparison with SUVmax, inflammatory biomarkers and ITAS-2010 score in a cohort of TAK patients. Methods: Sixty-four PET/CT scans acquired from 54 TAK patients were analyzed. The inflammatory activity was qualitatively determined by physician's global assessment and quantitatively determined by ITAS-2010 score. SUVmax and PETVAS were acquired by consensus review. Levels of the inflammatory biomarkers C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and pentraxin-3 (PTX-3) were measured. Performance of the qualitative diagnoses and the quantitative correlation were, respectively, compared by receiver operating characteristic (ROC) curve and Spearman correlation coefficient. Results: The biomarkers (CRP, ESR, PTX-3), PET uptake values (SUVmax, PETVAS), and ITAS-2010 scores were all significantly higher in active patients than in non-active ones. The area under the ROC curve and Youden Index of PETVAS and PTX-3 were higher than those of SUVmax, CRP, ESR, and ITAS-2010. PETVAS and PTX-3 resulted in a higher Spearman correlation coefficient with ITAS-2010 than other criteria, either among all patients or within the active group. Alteration trends of PETVAS and PTX-3 during follow-up showed a tighter correlation with clinical progression/remission assessment than other criteria. Conclusions: In TAK evaluation, PETVAS is superior for qualitative and quantitative assessment, compared with the regional SUVmax. Compared to CRP and ESR, inflammatory biomarker PTX-3 shows better qualitative performance and a higher correlation with PETVAS and ITAS-2010. These findings indicate that the use of PETVAS and PTX-3, instead of SUVmax and CRP/ESR, has potential advantages in the clinical evaluation of TAK. [ABSTRACT FROM AUTHOR]

The extruded Mg–7Y–1Nd–0.5Zr (wt%) alloy were performed to the same strain hot rolling with different temperatures. The microstructure and texture evolution of the sheets were investigated by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and electron back-scattered diffraction (EBSD). The results indicate that the microstructure becomes homogeneous after hot rolling process and precipitated phase distributes at grain boundaries along rolling direction. With the increase in rolling temperature, the grains of sheet grow up. The sheet rolling at 400 °C is composed of recrystallization grains, the necklace of the precipitated phase in the grain boundaries and excessive dislocations. The structure of necklace of the precipitated phase is fcc structure with lattice constant of a = 0.75 nm. With rolling temperatures increasing from 400 to 450 °C, the content of recrystallized grains in volume fraction with relatively random orientations increases significantly. Compared with the rolling process at 400 °C, the amount of precipitated phases is reduced at the grain boundary, and the precipitated phase begins to appear in the grain interior when rolling at 450 °C. The structure of the precipitated phase is fcc with lattice constant of a = 2.22 nm. The recrystallization grains begin to grow in the rolling process at 500 °C. The basal texture is obviously produced during the rolling process at 400 and 450 °C; however, the basal texture is weak in the rolling process at 500 °C. The pole point of the (0002) pole figure is concentrated in the center. It can be seen that the basal surface is parallel to RD–TD surface of the rolling sheets. Compared with as-extruded alloy, the basal texture is significantly enhanced with a small increase in basal texture intensity from 6.127 to 7.175, and (10 1 ¯ 0) and (11 2 ¯ 0) textures change to random textures. [ABSTRACT FROM AUTHOR]

The microstructures and mechanical properties of Mg–7.0 wt%Y–1.0 wt%Nd–0.5 wt%Zr magnesium alloy were investigated both in as-cast condition and after homogenization heat treatment by differential scanning calorimetry (DSC), optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and hardness measurement. The results indicate that the as-cast alloy consists of α-Mg matrix, Mg24Y5 and Mg41Nd5 phases, which are eutectic phases (cubic Y-rich phase). With the increase in homogenization temperature and time, the Mg24Y5 and Mg41Nd5 phases are completely dissolved into matrix, and only yttrium of intermetallic compounds leaves around boundary. After homogenization heat treatment, the elements distributed uniformly and the grains grow up not obviously, only yttrium element of intermetallic compounds left around boundary. The optimum homogenization condition is at 537 °C for 16 h. The mechanical properties are improved after homogenization, with tensile strength of σb = 181 MPa, yielding strength of σ0.2 = 144 MPa and elongation of δ = 5.5 %, which are better than those of as-cast alloy. [ABSTRACT FROM AUTHOR]

The Mg–Zn–Ca–Sr alloy has good application prospects as a bone implant material; however, the as-cast alloy has both poor plasticity and formability, and there are few studies on its deformation properties. In this study, the microstructure, deformation behavior, textural evolution, and processing map of an Mg–3wt%Zn–1wt%Ca–0.5wt%Sr alloy were studied via a compression test using a Gleeble 1500D thermo-mechanical simulator. The mean apparent activation energy of the hot compression deformation of the Mg–3wt%Zn–1wt%Ca–0.5wt%Sr alloy was 250.44 kJ/mol. With an increase in temperature, both the grain size and the degree of dynamic recrystallization increased. Dynamically recrystallized grains predominantly nucleated near the grain boundary and the secondary phases. After compression, the alloy had a strong basal texture, and its textural strength decreased at first and then increased slightly as the deformation temperature rose. The optimal process parameters of the as-cast Mg–Zn–Ca–Sr alloy involved deformation temperatures of 603–633 K and strain rates of 0.03–0.005 s–1. [ABSTRACT FROM AUTHOR]