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Laser directed energy deposition (DED-LB) technology is currently facing challenges in controlling geometry accuracy of metal components. There is an urgent need to develop a numerical model that is more efficient and accurate compared to existing models and to analyze the dynamic behavior of the melt pool under the interaction of process parameters during DED-LB process to optimize parameters with fewer experimental studies to reduce costs. Therefore, a three-dimensional powder-scale multi-physics model is proposed during the single-track DED-LB process in this study. The powder particles are added by a Lagrangian particle model in this model without the need for assuming that the powder particles entering the molten pool are added by the mass source term, which improves model accuracy and efficiency. The effects of energy per unit mass (EUM, J g−1), mass per unit length (MUL, g mm−1), and standoff distance (SD, mm) intensities on transient molten pool motion and flow field are comprehensively investigated. It is discovered that the proposed model is able to predict the single-track height, width, depth, and dilution rate, or less than 9% relative error from experimentation, providing a useful tool for track geometry to predict. Furthermore, the flow velocity, width, and depth of melt pool also gradually are improved with higher EUM, MUL, and SD intensity and fluctuate within a small range. However, the height is improved and then decreases with higher SD intensity, and is improved with higher EUM or MUL. Overall, this study contributes to developing an optimizing process approach to improve formation accuracy for DED-LB manufacturing. [ABSTRACT FROM AUTHOR]

At present, in the directed energy deposition (DED) of metals, the heat transfer of the melt pool and microstructural evolution are not fully understood. This study investigates the thermal effect on the microstructure and the mechanical properties of DED AISI 316L, using in situ optical monitoring. Five thin-wall samples were tested to determine the effect on microstructural evolution and mechanical properties with variable laser powers and scanning speeds. A comprehensive optical monitoring system with a CMOS (coaxial complementary metal oxide semiconductor) visual module and an infrared camera was adopted in analyzing the temperature gradient and the solidification rate. The emissivity of the melt pool was calibrated, using the melt pool length, extracted from the coaxial visual image. The results showed that microstructures mainly consist of the coarse columnar grain and the equiaxed grain at the top layer of AISI 316L samples. The direction of epitaxial growth of columnar grains is affected by the compromise between directional heat flux and crystallographic direction. High numerical temperature gradient and high solidification rate are beneficial to obtaining fine grain size and high yield stress. A modified microstructure map for DED AISI316L was established, which correlates the solidification parameters with a solidification microstructure. This research study, combining temperature distribution, solidification parameter, microstructure, and tensile property, provides an experimental identification of solidification parameters and the model on the solidification theory for precision control of DED process. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate whether the periprostatic adipose tissue thickness (PPATT) is an independent prognostic factor for prostate cancer patients after laparoscopic radical prostatectomy (LRP). This retrospective cohort study included consecutive prostate cancer patients who underwent LRP treatment at Wuhan Union Hospital from June 2, 2016, to September 7, 2023. PPATT was defined as the thickness of periprostatic fat and was obtained by measuring the shortest vertical distance from the pubic symphysis to the prostate on the midsagittal T2-weighted MR images. Subcutaneous adipose tissue thickness (SATT) was obtained by measuring the shortest vertical distance from the pubic symphysis to the skin at the same slice with PPATT. The primary outcome of the study was biochemical recurrence (BCR), and the secondary outcome was overall survival (OS). Multivariable Cox regression analysis was used to identify independent prognostic factors for prostate cancer survival and prognosis. Based on the optimal cutoff value, 162 patients were divided into a low PPATT/SATT group (n = 82) and a high PPATT/SATT group (n = 80). During the entire follow-up period (median 23.5 months), 26 patients in the high PPATT/SATT group experienced BCR (32.5%), compared to 18 in the low PPATT/SATT group (22.0%). Kaplan–Meier curve analysis indicated that the interval to BCR was significantly shorter in the high PPATT/SATT group (P = 0.037). Multivariable Cox regression analysis revealed that an increase in the PPATT/SATT ratio was associated with BCR (hazard ratio: 1.90, 95% CI, 1.03–3.51; P = 0.040). The PPATT/SATT ratio is a significant independent risk factor for BCR after LRP for prostate cancer patients. [ABSTRACT FROM AUTHOR]

Background: To evaluate whether increasing total gonadotropin (Gn) dose is associated with changes in euploid blastocyst rate in preimplantation genetic testing (PGT) oocytes. Methods: This retrospective cohort study was conducted between 2017 and 2022, and 19,246 oocytes were grouped and analyzed based on tri-sectional quantiles of total Gn doses. Setting: Single reproductive medical center. Subjects: All the patients who underwent PGT cycles, including PGT for aneuploidy, monogenic disorders, and structural rearrangements, were included. Exposure: Next-generation sequencing platforms for chromosomal analysis. Main outcome measures.: Blastocyst formation and euploid blastocyst rates. Results: In total, 19,246 oocytes and 5375 PGT blastocysts were analyzed. There were significant differences in blastocyst formation and euploid blastocyst rates among the groups classified according to tri-sectional quantiles of total Gn doses. Significant differences in age, body mass index (BMI), proportion of primary infertility, anti-Müllerian hormone (AMH) levels, number of oocytes retrieved, controlled ovarian stimulation (COS) regimen, type of Gn, and PGT category were observed among the three groups. After stratifying the analysis by age, BMI, infertility diagnosis, AMH levels, number of oocytes retrieved, PGT category, type of Gn, and COS regimen, significant differences were only seen in a small number of specific subgroups. Furthermore, the results of the multiple logistic regression analysis showed that the blastocyst formation and euploid blastocyst rates did not significantly increase or decrease with the total Gn dose, whether treated as a continuous variable or divided into three Gn groups as categorical variables. Notably, advancing age was a risk factor for blastocyst formation and euploid blastocyst rates. PGT for structural rearrangements was a risk factor for blastocyst formation and euploid blastocyst rates as compared with PGT for aneuploidy. Conclusion: In the total PGT cycles, advancing age, and preimplantation genetic testing for structural rearrangements negatively affected blastocyst formation and euploid blastocyst rates; however, the total Gn dose did not affect blastocyst formation and euploid blastocyst rates. [ABSTRACT FROM AUTHOR]

The mechanization level of coal mine in China has been developed toward automation and intelligence, which puts forward new requirements for the support mode of the advanced section of the two roadways. Given the problems of high labor intensity of passive advanced support, the 1203 working face of Xima Coal Mine is taken as the research object, and the idea of advanced active support of backfilling stopes is proposed. The supporting force of the surrounding rock and the required reinforcement support strength are obtained through theoretical calculation. The "full-roadway roof anchor cable reinforcement support" technology is proposed, and its strength is verified. The mineral pressure distribution law of the backfilling stope was revealed through numerical simulation. Finally, field verification is carried out through on-site industrial tests. The test results show that the relative proximity of the roof and floor of the roadway and the maximum relative approach of the two sidewalls are 105.56 mm and 47 mm, respectively. It can be seen that advanced active support can meet the support quality requirements of advanced support pressure area, improve the working environment of workers, and increase the efficiency of mine mechanization. Highlights: Calculated the surrounding rock support force The stress pattern of the backfill stopes was studied Active over-support solution applied Field measurements to determine the feasibility of the program Reduced worker labor and increased mechanization [ABSTRACT FROM AUTHOR]

Leaf area index (LAI) is a vital input variable for crop growth and yield prediction models. Therefore, rapid and accurate crop LAI estimates can offer important information for monitoring and managing the quantity and quality of food production. Here, LAI values of maize and soybean were predicted applying height metrics and intensity metrics calculated through unmanned aerial vehicle (UAV) LiDAR data. Moreover, we compared the prediction performance of physical model with that of empirical model for estimating crop LAI. The physical model based on Beer–Lambert law yielded reliable estimation results using LiDAR height data (maize: R2 = 0.815, RMSE = 0.385; soybean: R2 = 0.627, RMSE = 0.515) and LiDAR intensity data (maize: R2 = 0.719, RMSE = 0.474; soybean: R2 = 0.548, RMSE = 0.567). However, the linear regression model obtained a higher estimation accuracy. The single linear regression model derived from LiDAR height data had an R2 value of 0.837 (RMSE = 0.361) for maize and 0.658 (RMSE = 0.493) for soybean, and derived from LiDAR intensity data had an R2 value of 0.749 (RMSE = 0.448) for maize and 0.460 (RMSE = 0.619) for soybean, respectively. We found that the random forest (RF) regression model yielded the lowest estimation accuracy in this study. Moreover, the RF regression model in our study was not able to reliably estimate soybean LAI whether using LiDAR height metrics (R2 = 0.294) or intensity metrics (R2 = 0.180). Our results show that both LiDAR intensity and height metrics are capable of reliably predicting maize and soybean LAIs, although LiDAR intensity data yielded lower estimation accuracy than LiDAR height data. In conclusion, the results presented in this study demonstrate that using UAV-LiDAR technology to predict crop LAI is a flexible, practical, and cost-effective method. [ABSTRACT FROM AUTHOR]

As an advanced metal additive manufacturing technology, laser-directed energy deposition (DED-LB) has attracted a lot of attention in recent years, and is increasingly used in aerospace, automotive, marine, and biomedical applications. However, as industry application standards continue to improve, the challenges of part quality, process stability, and molding efficiency faced by DED-LB are becoming more and more prominent. On-line monitoring and real-time quality regulation can effectively avoid quality defects in processing, which is an effective measure to solve the problem. This paper summarizes the current research status of on-line monitoring means and closed-loop quality regulation technology for DED-LB. The on-line monitoring signals and related sensing devices mainly based on image signals, temperature signals, spectral signals, acoustic emission signals, and X-ray imaging, as well as the closed-loop control strategies and intelligent optimization methods in the process are discussed. Finally, a view on the future direction of on-line monitoring-control system for DED-LB is presented. [ABSTRACT FROM AUTHOR]

Ti6Al4V scaffolds were successfully fabricated using selective laser melting followed by vacuum impregnation of gentamicin loaded chitosan. Microstructural observation revealed that Ti6Al4V scaffolds display primary columnar β grains, in which a hierarchical structure of acicular α′ martensites of varying sizes was observed. Compressive tests indicated that a scaffold with 59% porosity exhibited a compressive yield strength of ~ 236 MPa and a failure strain of ~ 30.4%. The drug release behavior of the gentamicin-loaded scaffolds was characterized by an initial burst release of gentamicin lasting up to 184 h, followed by a slower, sustained release over the subsequent period up to 496 h. This research is expected to open up a new avenue for the development of gentamicin-loaded Ti6Al4V scaffolds for practical clinical applications. [ABSTRACT FROM AUTHOR]

The nurturing of offspring within divorced families has consistently been a matter of concern. Parental divorce is a pivotal environmental determinant influencing the progression of adolescents' prosocial behavior. Apart from the family, school serves as another significant sphere for adolescents, hence, school acceptance and support might also bear a substantial impact on shaping adolescents' prosocial behavior. This investigation undertook a comprehensive longitudinal survey to elucidate the correlation between parental divorce and prosocial behavior in adolescents, subsequently exploring the moderating role of school acceptance and support on the connection between parental divorce and prosocial behavior. A collective sample of 1,655 and 1,322 Chinese adolescents partook in this study during the first year (Term 1 - T1) and the subsequent year (Term 2 - T2), respectively. The findings demonstrated that parental divorce was negatively correlated with prosocial behavior in adolescents, both concurrently and longitudinally. Additionally, school acceptance and support altered the relationship between parental divorce and prosocial behavior. Specifically, school acceptance and support could ameliorate the detrimental effect of parental divorce on prosocial behavior in adolescents. This study provides a unique perspective which may be beneficial in fostering adolescents' prosocial behavior in divorced households. [ABSTRACT FROM AUTHOR]

Objectives: This randomized controlled trial (RCT) assessed the effectiveness of a community-infused problem-oriented policing (CPOP) intervention on reducing property/violent crime. Methods: In two mid-Atlantic cities, a total of 102 crime hot spots were randomly assigned to receive CPOP or standard patrol. Analyses examine changes in crime the year before, during, and one year after the intervention. We used hierarchical Poisson regression models. Results: We found no main effects for the CPOP intervention on property and violent crimes in either site. In site B, the violent crime count in low treatment hot spots was 200% higher than controls post-intervention but this likely reflected officers paying less attention to treatment locations with lower levels of crime. Conclusions: Our results suggest that CPOP was not effective in the unusual context of the COVID-19 pandemic and post-George Floyd killing. Given the challenges of implementing CPOP during this unique time, caution is needed in interpreting these findings. [ABSTRACT FROM AUTHOR]

Objective: The objective of this scoping review was to investigate the effectiveness and limitations of risk prediction models for postpartum glucose intolerance in women with gestational diabetes mellitus (GDM). The aim was to provide valuable insights for healthcare professionals in the development of robust risk prediction models. Methods: A comprehensive literature search was conducted across multiple databases, including PubMed, EBSCO, Web of Science Core Collection, Ovid Full-Text Medical Journal Database, ProQuest, Elsevier ClinicalKey, China National Knowledge Infrastructure, China Biology Medicine, and WanFang Database, spanning from January 1990 to July 2023. To assess the quality of the included models, the Predictive Model Risk of Bias Assessment Tool (PROBAST) was employed. Results: Fourteen relevant studies were identified and included in the final review, all focusing on model development. The discrimination ability of the included models ranged from 0.725 to 0.940, indicating satisfactory prediction accuracy. However, a notable limitation was that nine of these models (64.3%) did not provide clear guidelines on the selection of potential predictors. Furthermore, only six models (42.86%) underwent internal validation, with none undergoing external validation. A high risk of bias was observed across the included models. Logistic regression, Cox regression, and machine learning were the primary methods employed in the construction of these models. Conclusion: The risk prediction models included in this review demonstrated favorable prediction accuracy. However, due to variations in construction methodologies, direct comparison of their performance is challenging. These models exhibited certain shortcomings, such as inadequate handling of missing data and a lack of internal and external validation, resulting in a high risk of bias. Therefore, it is recommended that these models be updated and externally validated. The development of prospective, multi-center studies is encouraged to construct predictive models with low risk of bias and high clinical applicability, ultimately guiding evidence-based clinical practice. [ABSTRACT FROM AUTHOR]

Using a randomized controlled trial, we investigated changes in both sexual harassment (SH) perpetration and victimization of 2104 middle school students in New York City who received divergent saturation and dosage levels of Shifting Boundaries, an SH prevention program, which was represented by the length of the program. We assessed the saturation effect of the program by comparing the outcomes across respondents from 26 schools in which there were varying percentages of students enrolled in the program. The data suggested that, overall, the program was effective in reducing sexual harassment victimization but achieved a null effect against respondents' SH perpetration and that neither the length nor the school-saturation level of the program exerted a significant effect on SH perpetration. Although the data indicated a significant difference in SH victimization between the treatment and control group, when comparing subgroups who received treatment with divergent saturation and dosage levels, no statistically significant difference was identified. Our results suggested that the program effect was not contingent on the portion of students in a school who enrolled in the program, nor was it contingent on the dosage. [ABSTRACT FROM AUTHOR]

Coal is a non-renewable fossil energy source on which humanity relies heavily, and producing one ton of raw coal requires the discharge of 2–7 tons of mine water from the ground. The huge drainage task increases the cost of coal mining in coal mines significantly, so saving the drainage cost while guaranteeing the safe production of coal mines is a problem that needs to be solved urgently. Most of the fuzzy controllers used in the traditional dynamic planning methods applied to mine drainage are two-dimensional fuzzy controllers with limited control effect, so the traditional two-dimensional fuzzy controllers are improved by introducing the rate of change of gushing water to form a three-dimensional fuzzy controller with three-dimensional control of instantaneous section—water level—rate of change of gushing water, and at the same time, the optimized dynamic planning method is designed by combining the Avoiding Peak Filling Valley strategy and the optimal dy-namic planning method is used in conjunction with the un-optimized dynamic planning method. The optimized dynamic planning method is applied to the same coal mine water silo gushing water experiments; experimental comparison found that the pumping station system before the optimi-zation of the electricity consumed is 52,586 yuan/day, while after the optimization of the electricity consumed is reduced to 41,692 yuan/day, the cost per day consumed compared with the previous reduction of 20.69%, a year can be saved 3,969,730 yuan. Therefore, the mine water bin drainage method based on fuzzy control and Avoiding Peak Filling Valley strategy proposed in this paper can be used as an improvement method of the existing mine drainage method, which can further ex-pand the economic benefits of coal mines and realize safe production while realizing cost savings. [ABSTRACT FROM AUTHOR]

Endothelial dysfunction is a key factor in the occurrence of coronary artery disease and plays a vital role in the pathological development of myocardial infarction. Hypoxia contributing to endothelial cell survival and growth, metabolism and angiogenesis. HMGB1 has been identified as one of the factors involved in the regulation of vascular endothelial cell function. However, the mechanisms by which HMGB1 regulates endothelial cells under hypoxia remain unclear. Our study aimed to determine HMGB1 expression investigate the functions of HMGB1 on endothelial cell in hypoxia environment. The expression of extracellular high-mobility group box 1 (HMGB1) in cardiac endothelial cells treated with hypoxia was detected by western blot analysis. 5-Ethynyl-2′-deoxyuridine (EdU) assays and transwell assays were performed to determine the cell proliferation and migration, and flow cytometry assay was performed to evaluate the apoptosis of cardiac endothelial cell. Intracellular HMGB1 expression was upregulated in hypoxia-induced cardiac endothelial cells. HMGB1 silencing significantly promoted apoptosis and inhibited the proliferation and migration of hypoxia-induced cardiac endothelial cells. Moreover, silencing YAP1 on the basis of silencing HMGB1 can aggravate apoptosis and inhibit proliferation and migration of cardiac endothelial cells in hypoxic microenvironment. HMGB1 is up-regulated in hypoxic environment, which may be regulate the biological function of cardiac endothelial cells by YAP1, revealing that HMGB1/YAP1 may be partially involved in the protective mechanism of cardiac endothelial cells. To the best of our knowledge, this study provides a novel basis for the development of treatment methods for ischemic heart diseases. [ABSTRACT FROM AUTHOR]

In order to evaluate the damage deterioration degree of freeze–thaw rock under in-situ stress in cold area engineering, it is necessary to establish the triaxial compression damage constitutive model and study on meso-failure characteristics of freeze–thaw rock. The triaxial compression tests under confining pressure of 3 MPa, 5 MPa, and 10 MPa were carried out on saturated sandstone after 0, 20, 40, and 60 freeze–thaw cycles. The results show that with the increase of freezing–thawing times, the peak deviatoric stress and elastic modulus under the same confining pressure decrease gradually, and increase gradually with the increase of confining pressure. The triaxial compression damage constitutive model of freeze–thaw rock was established based on the dissipation energy ratio and the principle of minimum energy dissipation. Based on this model, the evolution law of energy ratio in different stages of compression process was studied, and the influence characteristics of confining pressure and freeze–thaw on rock failure were analyzed. PFC2D was used to establish the numerical method on triaxial compression of frozen-thawed rock and determine the calculation parameters. The energy evolution law and the number growth law of different cracks in the triaxial compression process of frozen-thawed rock were studied. It is found that the energy value at the peak and the ratio of tensile crack to shear crack decrease with the number of freezing–thawing cycles. Meanwhile, the characteristics of freezing–thawing cycles promoting the shear failure of rock were clarified. [ABSTRACT FROM AUTHOR]

Coping skills have been shown to contribute significantly to law enforcement officers' ability to manage a variety of personal and professional stressors. Research has identified various coping styles without a consensus as to which styles are most beneficial. The objective of this study was to examine US law enforcement officers' coping styles and to determine if a particular coping style was equated with the best health outcomes. In a national representative sample of 1517 law enforcement officers, latent class analysis was applied to determine heterogeneity of coping styles. Subsequent classes were modeled as predictors of both behavioral and mental health challenges and constructive health behaviors. Results indicate that coping styles predict officers' perceived stress, anxiety and depression, suicidality, alcohol abuse, and diet. Specifically, a task-oriented, problem-focused coping style was most effective. These findings highlight the importance of training officers to manage adversity with the most effective coping strategies. [ABSTRACT FROM AUTHOR]

In the direct laser deposition (DLD) process, it is common to employ constant processing parameters. The utilization of the constant parameters may lead to fluctuations in the dynamic evolution of the molten pool, primarily due to the intricate thermal effects involved, which will significantly impact the processing quality. To address this issue, this study proposed a closed-loop control approach that effectively modifies processing parameters in real time by targeting on the molten pool transient area. The type of the laser used in this study is a flat-top beam. Laser power, powder feeder rate, and scanning speed are the input variables of the study to control molten pool, considering the manufacturing system. The most suitable processing parameter to control the molten pool area was found to be the laser power by a set of orthogonal experiments, with a correlation coefficient of 0.706, and significance level of 0.002. Then, the dynamic response relationship between laser power and the molten pool area was mathematically characterized by a third-order transfer function model to simplify the complex physical model of the DLD process. Subsequently, a PID controller with a filtering coefficient and anti-windup compensation was chosen compared with the other controller. In the validation experiments, it was observed that the closed-loop processing group demonstrated improved stability in maintaining the molten pool transient area, with a notable decrease of 33.7% in variability compared to the open-loop processing group. As a result, the deposited layer of the closed-loop processing group exhibited a much more satisfying surface quality and heat affect zone than the open-loop group. This study established a third-order mathematical model of the dynamic molten pool and realized the optimization of deposition quality by controlling the molten pool transient area with an enhanced PID controller, providing a fundamental basis for improving the consistency of the direct laser deposition processing quality through the implementation of real-time feedback control of molten pool physics. [ABSTRACT FROM AUTHOR]

Streams may have many branches and form complex river networks. We investigate two competition patch models associated with two different river network modules, where one is a distributary stream with two branches at the downstream end, and the other is a tributary stream with two branches at the upstream end. Treating one species as resident species and the other one as mutant species, it is shown that, for each model, there exists a invasion curve such that the mutant species can invade when rare if and only if its dispersal strategy is below this curve, but the shapes of the invasion curves are different. Moreover, we show that the global dynamics of the two models can be similar or different depending on river networks. Especially, if the drift rates of the two species are equal, then the global dynamics are similar for small drift rate and different for large drift rate. Our results also confirm a conjecture in Jiang et al. (Bull Math Biol 82:131, 2020). [ABSTRACT FROM AUTHOR]

The rapid development of computational technology and the increasing energy demand have improved heat exchanger network (HEN) synthesis. The HEN synthesis involves several optimizations of matches, distributions of heat loads, and stream splitting of heat units. Thus, obtaining good results at high efficiency has been the main standard for evaluating the techniques in the research area of HEN synthesis. This paper first summarizes and analyzes the main contributions of the existing HEN synthesis techniques. To compare related data quantitively, information on ten typical cases is presented in this paper. Furthermore, recently improved solutions for commonly encountered existing literature cases demonstrate the evolution and competition trends in the field of HEN synthesis. The comparison data presented in this paper not only provide a useful reference for future research but also present the optimization directions. Based on the findings of this study, it is noted that there is still a large room for improvement, and current approaches are incapable of dealing with all HEN cases. Moreover, it is still difficult to escape a local optimum and overcome structural constraints when seeking the global optimum. As a follow-up to the current work, the parallel computing mode and adaptively coordinating the ratio of global and local searching abilities are major development trends for future investigation. [ABSTRACT FROM AUTHOR]

This paper mainly deals with the current status and development trends of research on the microstructure and properties of additive manufacturing formed parts. According to the laser processes and powder processing, the microstructure of the parts including morphologies, phase composition, and grain orientation is analyzed; the forming quality of the parts including hardness, wear resistance, corrosion resistance, strength, fracture toughness, residual stresses, and fatigue properties is analyzed in many ways. At the same time, we expect to find the research directions that conform to the future development trends for LAM. [ABSTRACT FROM AUTHOR]

Purpose: This meta-analysis was aimed at exploring the incidence and risk factors of glucose intolerance in women with gestational diabetes mellitus (GDM) at 6–12 weeks postpartum to inform the development of preventive strategies. Method: We searched Pubmed, Embase, Web of Science, the Cochrane Library, Ovid, China Knowledge Resource Integrated Database (CNKI), Wanfang Database and China Biology Medicine Database for entries between January 1990 and September 2022. The search terms included gestational diabetes mellitus, postpartum, glucose intolerance and type 2 diabetes. The meta-analysis was conducted using Stata 14.0. Result: We included 37 studies, with 21 and 16 having low and medium risk of bias, respectively. The incidence of glucose intolerance in women with GDM 6–12 weeks postpartum was 27% (95% CI: 0.22–0.33). The following risk factors for GDM 6–12 weeks postpartum were identified: insulin use during pregnancy (OR = 3.23; 95% CI: 2.35–4.44), family history of diabetes (OR = 2.94; 95% CI: 1.98–4.33), abnormal fasting glucose levels at 24–28 weeks of gestation (OR = 1.15; 95% CI: 1.07–1.25), high pre-pregnancy BMI (OR = 1.63; 95% CI: 1.23–2.15), abnormal triglyceride levels during 28–40 weeks of gestation (OR = 2.18; 95% CI: 1.18–4.03), abnormal HbA1c levels at 28–40 weeks of gestation (OR = 6.62; 95% CI: 4.71–9.30), history of previous GDM (OR = 2.11; 95% CI: 1.27–3.49), and high 1-h glucose levels at 24–28 weeks of gestation (OR = 1.16; 95% CI:1.06–1.28). Conclusion: The incidence of glucose intolerance in GDM patients at 6–12 weeks postpartum was high. To prevent early postpartum glucose intolerance, healthcare providers should develop individualized interventions for GDM patients, depending on existing risk factors. [ABSTRACT FROM AUTHOR]

HCC is one of the most common malignant tumors worldwide. Although traditional treatment methods have been improved in recent years, the survival rate of HCC patients has not been significantly improved. Immunotherapy has shown extremely high clinical value in a variety of tumors. In this study, we found that TUG1 could regulate the expression of PD-L1 through JAK2/STAT3 to mediate immunosuppression. Here, The expression of TUG1 and PD-L1 in HCC tissues was evaluated through analysis of databases and verified in HCC tissue and HCC cancer cells by qRT-PCR. The effect of TUG1 on tumor immune escape was detected by coculture, and cell viability was detected with a CCK8 assay. The results demonstrated that TUG1 was closely associated with anticancer immunity. TUG1 and PD-L1 were highly expressed in HCC tissues and HCC cancer cells, and high expression of TUG1 and PD-L1 was related to the poor prognosis of HCC patients. In addition, knocking down TUG1 expression could reduce PD-L1 expression and enhance the cancer cell-killing capability of T cells. Downregulating TUG1 expression could also decrease the mRNA and protein expression of JAK2 and STAT3. To sum up, TUG1 and PD-L1 are overexpressed in patients with liver cancer and are related to the poor prognosis of these patients. Silencing TUG1 expression reduced the mRNA and protein expression of PD-L1 by affecting the JAK2/STAT3 pathway. [ABSTRACT FROM AUTHOR]

Background: Cancer stem cells (CSCs) have unique biological characteristics, including tumorigenicity, immortality, and chemoresistance. Colorectal CSCs have been identified and isolated from colorectal cancers by various methods. AKAP12, a scaffolding protein, is considered to act as a potential suppressor in colorectal cancer, but its role in CSCs remains unknown. In this study, we investigated the function of AKAP12 in Colorectal CSCs. Methods: Herein, Colorectal CSCs were enriched by cell culture with a serum-free medium. CSC-associated characteristics were evaluated by Flow cytometry assay and qPCR. AKAP12 gene expression was regulated by lentiviral transfection assay. The tumorigenicity of AKAP12 in vivo by constructing a tumor xenograft model. The related pathways were explored by qPCR and Western blot. Results: The depletion of AKAP12 reduced colony formation, sphere formation, and expression of stem cell markers in colorectal cancer cells, while its knockdown decreased the volume and weight of tumor xenografts in vivo. AKAP12 expression levels also affected the expression of stemness markers associated with STAT3, potentially via regulating the expression of protein kinase C. Conclusion: This study suggests Colorectal CSCs overexpress AKAP12 and maintain stem cell characteristics through the AKAP12/PKC/STAT3 pathway. AKAP12 may be an important therapeutic target for blocking the development of colorectal cancer in the field of cancer stem cells. [ABSTRACT FROM AUTHOR]

Dendrobium officinale pomace (DOP) is a high-fiber source derived from an industrial by-product. This study researched and compared the microstructure, physicochemical and functional properties of DOP and the total dietary fiber extracted from DOP (DOPF), with the goal of evaluating the potential applications of DOP or DOPF as a functional component in food products. DOPF exhibited a more porous structure and a less crystalline area compared with DOP. DOPF displayed higher water-holding capacity (20.12 g/g vs. 15.30 g/g in DOP), oil-holding capacity (10.99 g/g vs. 8.93 g/g in DOP) and water swelling ability (5.26 mL/g vs. 3.48 mL/g in DOP), but lower cation exchange capacity (189.87 mmol/kg vs. 334.34 mmol/kg in DOP). Moreover, DOPF exhibited higher cholesterol, nitrite ion, bile acid salt, glucose adsorption capacities and GDRI. Therefore, DOPF is a better choice for ideal supplements for dietary fiber and has the potential to increase the value of DOP in food applications. [ABSTRACT FROM AUTHOR]

We propose a robust fuzzy design model for a sustainable closed-loop supply chain network. The model is based on a risk dynamic regulation mechanism. In this way, we can solve the problem of sudden disruptions and uncertain demand in the supply chain of Chinese herbal medicines. We also develop a hybrid algorithm solution to solve the model and design a resilient supply chain network. The specific steps are as follows: (1) The risk dynamic regulation mechanism is created with strong risk resistance by considering the information sharing platform, facility defense, drying station scheduling, safety stock, and shared inventory. (2) Based on the dynamic risk regulation mechanism, we establish a sustainable Chinese herbal medicine supply chain network design model. Then, we use the robust fuzzy method and the epsilon constraint to deal with the uncertainty and integrate the model. (3) We introduce opposition-based learning, cosine convergence factor, and levy flight to the original Whale and Grey wolf algorithms to obtain the Hybrid algorithm, which is used to solve the processed model. The results show the model and algorithm proposed in this paper have strong applicability and advantages in designing closed-loop supply chain networks for Chinese herbal medicine and provide references for relevant decision-makers. Article highlights: • We establish a dynamic risk control mechanism with strong anti-risk ability, by considering the information sharing platform, facility defense, drying station scheduling, safety inventory, and other factors. This mechanism effectively enhances the resilience of the Chinese herbal supply chain network and reduces the risk of disruption. • We establish a sustainable closed-loop supply chain network design model, according to the particularity of the Chinese herbal medicine supply chain network in the process of processing, storage, and transportation. The model is based on the dynamic risk control mechanism. We use the robust fuzzy method to handle the uncertainty in the model. In this way, we can enhance the reliability of the Chinese herbal supply chain while effectively controlling costs. • We improve Grey Wolf Optimization Algorithm (GWO) and Whale Optimization Algorithm (WOA) through opposition-based learning, cosine convergence factor, and levy flight. We mixed the improved algorithm to obtain opposition-based levy Grey Whale optimization algorithm (OLGWOA). Through verification, it is concluded that OLGWOA has strong searchability. We also used OLGWOA to solve the model and found the adaptability between the algorithm and the model. [ABSTRACT FROM AUTHOR]

This study investigates variation in adolescent attitudes regarding dating violence under different conditions, the association of these conditional attitudes with subsequent adolescent relationship abuse (ARA), and youth and parent-reported characteristics associated with youth attitudes. The sample consists of 607 youth, as a subset from those who responded to a nationally representative longitudinal survey of dating violence. A latent class analysis identified three profiles of attitudinal patterns: No Tolerance for Hitting Partners (NT), Some Tolerance for Hitting Partners (ST), and High Tolerance for Hitting Partners (HT). The HT profile predicted subsequent physical (compared to the NT profile), sexual ARA perpetration (compared to both the NT and the ST profiles), and physical ARA victimization (compared to the NT profile). The ST profile predicted subsequent psychological ARA perpetration and victimization (compare to the NT profile). Results inform youth dating violence prevention programs to reduce ARA and intimate partner violence by changing youth attitudes toward dating violence. [ABSTRACT FROM AUTHOR]

Mesenchymal stem/Stromal cells (MSCs) have great therapeutic potentials, and they have been isolated from various tissues and organs including definitive endoderm (DE) organs, such as the lung, liver and intestine. MSCs have been induced from human pluripotent stem cells (hPSCs) through multiple embryonic lineages, including the mesoderm, neural crest, and extraembryonic cells. However, it remains unclear whether hPSCs could give rise to MSCs in vitro through the endodermal lineage. Here, we report that hPSC-derived, SOX17+ definitive endoderm progenitors can further differentiate to cells expressing classic MSC markers, which we name definitive endoderm-derived MSCs (DE-MSCs). Single cell RNA sequencing demonstrates the stepwise emergence of DE-MSCs, while endoderm-specific gene expression can be elevated by signaling modulation. DE-MSCs display multipotency and immunomodulatory activity in vitro and possess therapeutic effects in a mouse ulcerative colitis model. This study reveals that, in addition to the other germ layers, the definitive endoderm can also contribute to MSCs and DE-MSCs could be a cell source for regenerative medicine. Human pluripotent stem cell-derived endoderm progenitors differentiate into mesenchymal stem/stromal cells (MSCs) that express classic MSC markers and show therapeutic effects in an ulcerative colitis mouse model. [ABSTRACT FROM AUTHOR]

Composite skin-stringer structures are widely used in engineering, and the Z-pinning technology is employed to attach the skin-stringer structure to prevent it from debonding. In this paper, we propose a low-in-plane damage ZPI (Z-pin pre-hole insertion) technology for fabricating a simplified skin-stringer joint to investigate the tensile and impact properties of a Z-pinned skin-stringer structure. What's more, the failure modes and the toughening mechanism of the specimen have been analyzed. It is found that the ZPI process can reduce the likelihood of fiber crushing and breaking. In addition, the reduced Z-pin inclination angle of the ZPI process can reduce crack initiation and expansion at the bonded interface. The tensile tests reveal that a thicker Z-pin is more beneficial for improving the total energy absorption, while the thinner Z-pin is better for failure displacement at the same Z-pin volume content. Moreover, the use of 0° ply should be limited during the layer design. The impact tests show that the Z-pinning bridging effect is insignificant or even deteriorates under the high-speed impact. Z-pinning can also lessen deflection after impact and improve impact resistance. However, Z-pinning has little effect on the amount of impact energy absorbed by the specimen. Furthermore, Z-pins can effectively inhibit mode II crack propagation by fracturing themselves to making GIIC significantly higher, but when the specimen is penetrated, Z-pins cannot form a large bridging zone, and the snubbing effect is not evident. These results can provide some guidance for fabricating the Z-pinned skin-stringer joint. [ABSTRACT FROM AUTHOR]

Behind the frequent occurrence of business scandals, it is often the silence and connivance of organizational immorality. Moral voice, a kind of employee active moral behavior, inhibits and prevents the organizational unethical phenomenon. Some researchers have sought to explore how to arouse employee moral voice. However, the limited studies mainly investigated the antecedents of leadership styles, ignoring the impact of the organizational factor on moral voice. Based on the self-determination theory, the current study constructs a theoretical model about how socially responsible human resource management (SRHRM) affects employee moral voice via autonomous motivation and controlled motivation and further considering the moderating role of person–organization value fit. From a two-stage research method and the analysis of 260 valid data, we found that SRHRM promoted employee moral voice and this positive linkage was mediated by autonomous motivation but not by controlled motivation. Besides, the findings also revealed that person–organization fit moderated the indirect influences of SRHRM on moral voice via autonomous motivation, such that the indirect influence was stronger for a high level of person–organization value fit than the low level of person–organization value fit. Some theoretical and practical implications also be discussed. [ABSTRACT FROM AUTHOR]

This paper mainly discusses the current research status and development trend of on-line monitoring technology for laser additive manufacturing. We have analyzed various on-line monitoring techniques for laser additive manufacturing based on visual imaging, temperature field, spectral analysis, and acoustic principles. Numerous analyses are performed on the monitored objects, the melt pool, including melt pool temperature and morphology dimensions, and the formed parts, including microstructure and properties. The analysis of on-line monitoring techniques for laser additive manufacturing is expected to find the research directions that meet future development trends. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to compare the DNA methylation profiles of human embryos cultured in uninterrupted or interrupted incubators. Methods: This study included 9 women, ≤ 30 years old (range: 20–30 years), without a history of genetic diseases or smoking, undergoing ICSI treatment, and each woman donated one oocyte. Embryos were randomly assigned to culture in either time-lapse imaging or standard incubators after ICSI. We compared the DNA methylation profiles of human eight-cell embryos cultured in uninterrupted condition using time-lapse imaging (TLI) incubator (EmbryoScope) to those cultured in interrupted culture model using standard incubators (SI, G185 K-System). Nine single-cell whole-genome bisulfite sequencing (WGBS) datasets were analyzed, including four SI-cultured embryos and five TLI-cultured embryos at the eight-cell stage. Results: A total of 581,140,020 and 732,348,182 clean reads were generated from the TLI and SI groups, respectively. TLI-cultured embryos had similar genome-wide methylation patterns to SI-cultured embryos. There were no significant differences in the methylation and transcription levels of transposable elements and imprinted control regions. Although a total of 198 differentially methylated genes (DMGs) were identified, only five DMGs had significantly different transcription levels between the two groups. Conclusions: This is the first study to compare the DNA methylation profiles of embryos cultured in TLI and SI and will provide a foundation for evaluating the safety of TLI application in assisted reproductive technologies. However, further study with a larger cohort of samples was needed for the data validation. [ABSTRACT FROM AUTHOR]

Dynamic localization (DL) of photons, i.e., the light-motion cancellation effect arising from lattice's quasi-energy band collapse under a synthetic ac-electric-field, provides a powerful and alternative mechanism to Anderson localization for coherent light confinement. So far only low-order DLs, corresponding to weak ac-fields, have been demonstrated using curved-waveguide lattices where the waveguide's bending curvature plays the role of ac-field as required in original Dunlap-Kenkre model of DL. However, the inevitable bending losses pose a severe limitation for the observation of high-order DL. Here, we break the weak-field limitation by transferring lattice concepts from spatial to synthetic time dimensions using fiber-loop circuits and observe up to fifth-order DL. We find that high-order DLs possess superior localization and robustness against random noise over lower-order ones. As an exciting application, by judiciously combining low- and high-order DLs, we demonstrate a temporal cloaking scheme with flexible tunability both for cloak's window size and opening time. Our work pushes DL towards high-order regimes using synthetic-lattice schemes, which may find potential applications in robust signal transmission, protection, processing, and cloaking. Dynamic localization is a method of confining light. Here the authors demonstrate higher-order dynamic localization of photons in a synthetic temporal mesh lattice and discuss the idea of tunable temporal cloaking by combining different-order localizations. [ABSTRACT FROM AUTHOR]

Hypoxia can cause Epithelial–mesenchymal transition (EMT) in renal tubular cells, and in turn, renal fibrosis. We tested the expression of TRIM46, a member of tripartite motif-containing (TRIM) family proteins, and mesenchymal markers under hypoxia. Our results showed that hypoxia significantly enhanced expression of TRIM46 in HK2 human renal proximal tubular epithelial cells. Our data further showed that hypoxia led to upregulated expression of mesenchymal markers including α-smooth muscle actin, vimentin, and Snail, and downregulated expression of epithelial marker E-cadherin, coupled with an increased abundance of nuclear β-catenin. However, such effects were reversed when TRIM46 expression was knocked down. TRIM46 overexpression had similar effects as hypoxia exposure, and such effects were reversed when cells were treated with XAV-939, a selective inhibitor for β-catenin. Furthermore, we found that TRIM46 promoted ubiquitination and proteasomal degradation of Axin1 protein, a robust negative regulator of Wnt/β-catenin signaling activity. Finally, increased TRIM46 coupled with decreased Axin1 was observed in a rat renal fibrosis model. These data suggest a novel mechanism contributing to EMT that mediates hypoxia-induced renal fibrosis. Our results suggest that selectively inhibiting this pathway that activates fibrosis in human kidney may lead to development of a novel therapeutic approach for managing this disease. [ABSTRACT FROM AUTHOR]

We aimed to explore the effects of myeloid-derived growth factor (Mydgf) on the regulation of hypoxia/reoxygenation (HR)–induced apoptosis of cardiac microvascular endothelial cells (CMECs). CMECs were exposed to hypoxia for 24 h and reoxygenation for 6 h to establish an HR cell model. Subsequently, an adenovirus was used to overexpress Mydgf in CMECs. Flow cytometry and TUNEL staining were used to detect the extent of apoptosis, whereas qPCR was used to detect the relative expression of Mydgf mRNA. Western blotting was also performed to detect the expression of apoptosis-related proteins and endoplasmic reticulum stress (ERS)–related proteins, including C/EBP Homologous Protein (CHOP), glucose-regulated protein 78 (GRP 78), and cleaved Caspase-12. The endoplasmic reticulum stress agonist tunicamycin (TM) was used to stimulate CMECs for 24 h as a rescue experiment for Mydgf. Flow cytometry revealed that the HR model effectively induced endothelial cell apoptosis, whereas qPCR and western blotting showed that Mydgf mRNA and protein levels decreased significantly after HR treatment (P < 0.05). Overexpression of Mydgf in cells effectively reduced apoptosis after HR. Furthermore, western blotting showed that HR induced a significant upregulation of CHOP, GRP78, and cleaved-Caspase-12 expression in CMECs, whereas HR-treated cells downregulated the expression of CHOP, GRP78, and cleaved-Caspase-12 after Mydgf overexpression. Under HR conditions, TM significantly reversed the protective effect of Mydgf on CMECs. Mydgf may reduce CMEC apoptosis induced by HR by regulating oxidative stress in ERS. [ABSTRACT FROM AUTHOR]

Toll-like receptors/Interleukin-1 receptor signaling plays an important role in high-fat diet-induced adipose tissue dysfunction contributing to obesity-associated metabolic syndromes. Here, we show an unconventional IL-1R-IRAKM-Slc25a1 signaling axis in adipocytes that reprograms lipogenesis to promote diet-induced obesity. Adipocyte-specific deficiency of IRAKM reduces high-fat diet-induced body weight gain, increases whole body energy expenditure and improves insulin resistance, associated with decreased lipid accumulation and adipocyte cell sizes. IL-1β stimulation induces the translocation of IRAKM Myddosome to mitochondria to promote de novo lipogenesis in adipocytes. Mechanistically, IRAKM interacts with and phosphorylates mitochondrial citrate carrier Slc25a1 to promote IL-1β-induced mitochondrial citrate transport to cytosol and de novo lipogenesis. Moreover, IRAKM-Slc25a1 axis mediates IL-1β induced Pgc1a acetylation to regulate thermogenic gene expression in adipocytes. IRAKM kinase-inactivation also attenuates high-fat diet-induced obesity. Taken together, our study suggests that the IL-1R-IRAKM-Slc25a1 signaling axis tightly links inflammation and adipocyte metabolism, indicating a potential therapeutic target for obesity. TLRs/IL-1R signaling play a role in high-fat diet induced adipose tissue dysfunction and obesity-associated metabolic syndrome. Here the authors report that adipocyte-specific deficiency of IL-1 Receptor-Associated Kinase M (IRAKM) ameliorates diet induced obesity, potentially via the mitochondrial citrate carrier Slc25a1 and reduced de novo lipogenesis. [ABSTRACT FROM AUTHOR]

The C-type lectin receptor Mincle is known for its important role in innate immune cells in recognizing pathogen and damage associated molecular patterns. Here we report a T cell–intrinsic role for Mincle in the pathogenesis of experimental autoimmune encephalomyelitis (EAE). Genomic deletion of Mincle in T cells impairs TH17, but not TH1 cell-mediated EAE, in alignment with significantly higher expression of Mincle in TH17 cells than in TH1 cells. Mechanistically, dying cells release β-glucosylceramide during inflammation, which serves as natural ligand for Mincle. Ligand engagement induces activation of the ASC-NLRP3 inflammasome, which leads to Caspase8-dependent IL-1β production and consequentially TH17 cell proliferation via an autocrine regulatory loop. Chemical inhibition of β-glucosylceramide synthesis greatly reduces inflammatory CD4+ T cells in the central nervous system and inhibits EAE progression in mice. Taken together, this study indicates that sensing of danger signals by Mincle on TH17 cells plays a critical role in promoting CNS inflammation. Mincle is a pattern recognition receptor that senses danger signals in innate immune cells. Here authors show in an experimental autoimmune encephalomyelitis mouse model that tissue damage triggers Mincle signaling on inflammatory helper T cells, leading to inflammasome-mediated IL-1β production and reinforced inflammation. [ABSTRACT FROM AUTHOR]

Herein, Poly(4-Vinylpyridine) (PVP) and Poly(ethylene oxide) (PEO) mixed (PEA)2PbI4 films are fabricated by spin-coating method. The optical and SEM images exhibit improved morphology with more uniform and homogeneous surfaces after mixing PVP and PEO polymers, which increases with the concentrations of the polymers. XRD and FTIR measurements show that the crystal structure and functional group of the (PEA)2PbI4 film don't change after introducing the polymer. The optical bandgap of the polymer-mixed (PEA)2PbI4 films gradually increased with increasing the concentrations of PVP and PEO polymers. Moreover, the two-photon-pumped photoluminescence (TPL) has been boosted by 3.5 and 3.8 folds by mixing with 25% PVP and 25% PEO, respectively. Time-resolved PL measurements indicate that the PL lifetimes of the polymer-mixed (PEA)2PbI4 films have been increased, proving that the increased TPL emission is due to the improved crystalline quality and decreased trap states. This work provides an effective strategy to improve the crystalline quality and photoemission of the 2D perovskite films, which shows great promise for manufacturing high-performance optoelectronic devices based on 2D perovskites. [ABSTRACT FROM AUTHOR]

Rock mass pressure has always been a research hotspot in the field of tunnel engineering, especially in the super large-span tunnel, which is characterized by flat section, large excavation span, and complex stress field. Based on the Letuan Tunnel (a bi-directional tunnel with eight traffic lanes) of Binlai expressway expansion project in Shandong Province, China, this paper focused on the calculation method of rock mass pressure and the evolution law of load release in the construction process of the super large-span tunnel excavated by upper-bench central diaphragm (CD) method. Based on field measured data of Letuan Tunnel, the deformation behavior of primary lining and the distribution state of rock mass pressure during the tunnel construction were analyzed. According to the bearing mode of supporting structure, the mechanical models of different construction stages were established. Then, the rock mass pressures in different construction stages were back-calculated using mechanical models and compared with the measured values, and the evolution law of load release during the tunnel construction was discussed. The study results show that the tunnel deformation and rock mass pressure were significantly affected by the construction process and support form, and the excavation span was the key factor affecting the stability of rock mass. For the shallow-buried super large-span tunnel constructed by upper-bench CD method, the primary support of upper bench was under eccentric pressure. The comparison between the back-calculated value and the field measured value indicated that they were similar, and the average relative error was 17.23%. According to the concept of load release coefficient proposed in this paper, the load release coefficient after the pilot tunnel ahead (Part I) excavation reached 63%, and the load release coefficient after the pilot tunnel behind excavation (Part II) was 37%, which means that the rock mass pressure of Part I is increased about 59% due to the excavation of Part II. [ABSTRACT FROM AUTHOR]

To evaluate the deterioration degree of rock freeze–thaw damage in cold area engineering, it is necessary to establish an accurate freeze–thaw rock damage model and its uniaxial compression numerical simulation method. Therefore, indoor freeze–thaw cycle tests of saturated yellow sandstone were carried out. The porosity and P-wave velocity were measured, and uniaxial compression tests were conducted after different numbers of freeze–thaw cycles. The findings indicate that with an increasing number of freeze–thaw cycles, the elastic modulus, peak strength and wave velocity of the yellow sandstones gradually decrease, while the peak strain and the average porosity increase. The energy evolution law with different numbers of freeze–thaw cycles was analyzed, a freeze–thaw damage model was established according to the relative change in the dissipated energy ratio before and after freezing–thawing, and the accuracy of this damage model and five common damage models was evaluated by the uniaxial compressive strength and peak strain. The functional relationship between mesoscopic parameters and the number of freeze–thaw cycles was formulated to establish a numerical simulation method for saturated sandstones under uniaxial compression after freeze–thaw cycling. The reliability of the numerical method was verified by comparing the stress–strain curve, peak stress, peak strain and energy law with the experimental results. [ABSTRACT FROM AUTHOR]

Main conclusion: Two squalene synthase genes AlSQS1 and AlSQS2 were isolated fromAtractylodes lanceaand functionally characterized using in vitro enzymatic reactions. Atractylodes lancea is a traditional herb used for the treatment of rheumatic diseases, gastric disorders, and influenza. Its major active ingredients include sesquiterpenoids and triterpenes. Squalene synthase (SQS; EC 2.5.1.21) catalyzes the first enzymatic step in the central isoprenoid pathway towards sterol and triterpenoid biosynthesis. In this study, we aimed to investigate two SQSs from A. lancea using cloning and in vitro enzymatic characterization. Bioinformatics and phylogenetic analyses revealed that the AlSQSs exhibited high homology with other plant SQSs. Furthermore, AlSQS1 was observed to be localized in both the nucleus and cytoplasm, whereas AlSQS2 was localized in the cytoplasm and endoplasmic reticulum. To obtain soluble recombinant enzymes, AlSQS1 and AlSQS2 were successfully expressed as glutathione S-transferase (GST)-tagged fusion proteins in Escherichia coli Transetta (DE3). Approximately 68 kDa recombinant proteins were obtained using GST-tag affinity chromatography and Western blot analysis. Results of the in vitro enzymatic reactions established that both AlSQS1 and AlSQS2 were functional, which verifies their catalytic ability in converting two farnesyl pyrophosphates to squalene. The expression patterns of AlSQS and selected terpenoid genes were also investigated in two A. lancea chemotypes using available RNA sequencing data. AlSQS1 and AlSQS2, which showed relatively similar expression in the three tissues, were more highly expressed in the stems than in the leaves and rhizomes. Methyl jasmonate (MeJA) was used as an elicitor to analyze the expression profiles of AlSQSs. The results of qRT-PCR analysis revealed that the gene expression of AlSQS1 and AlSQS2 plummeted at lowest value at 12 h and reached its peak at 24 h. This study is the first report on the cloning, characterization, and expression of SQSs in A. lancea. Therefore, our findings contribute novel insights that may be useful for future studies regarding terpenoid biosynthesis in A. lancea. [ABSTRACT FROM AUTHOR]

All living organisms need energy to carry out their essential functions. The importance of energy metabolism is increasingly recognized in human pluripotent stem cells. Energy production is not only essential for cell survival and proliferation, but also critical for pluripotency and cell fate determination. Thus, energy metabolism is an important target in cellular regulation and stem cell applications. In this review, we will discuss key factors that influence energy metabolism and their association with stem cell functions. [ABSTRACT FROM AUTHOR]

Reversible addition-fragmentation chain transfer radical polymerization of styrene and maleic anhydride was successfully performed in continuous-flow microreactor. Results of the structural characterization showed that the obtained styrene-maleic anhydride (SMA) copolymers possessed controlled molecular weight, low dispersity and alternating structures. Subsequently, effects of the polymerization conditions, including reaction pressure, temperature, feed flowrate and tube length, on the polymerization kinetics and molecular structure of the SMA copolymers were investigated in detail. It was found that the reaction rate was increased as the reaction temperature increased within certain limits, as well as the feed flowrate due to the increased mass and heat transfer efficiency. Besides, first-order kinetics of the polymerization was observed when the reaction times were adjusted by only changing the tube length. Good stability was exhibited when the reaction conducted continuously for 10 h. This approach can reduce the reaction time significantly from several hours to about half an hour. [ABSTRACT FROM AUTHOR]

A near-infrared femtosecond laser is focused by a 100 mm-focal-length plano-convex lens to form a laser filament, which is employed to drill holes on copper targets. By shifting or rotating the focusing lens, additional aberration is imposed on the focused laser beam, and significant influence is produced on the aspect ratio and cross-sectional shape of the micro-holes. Experimental results show that when proper aberration is introduced, the copper plate with a thickness of 3 mm can be drilled through with an aspect ratio of 30, while no through-holes can be drilled on 3-mm-thickness copper plates by femtosecond laser with minimized aberration. In addition, when femtosecond laser filament with large astigmatism is used, micro-holes that had a length to width ratio up to 3.3 on the cross-section are obtained. Therefore, the method proposed here can be used to fabricate long oval holes with high aspect ratios. [ABSTRACT FROM AUTHOR]