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Background: Noninvasively and accurately predicting subcarinal lymph node metastasis (SLNM) for patients with non-small cell lung cancer (NSCLC) remains challenging. This study was designed to develop and validate a tumor and subcarinal lymph nodes (tumor-SLNs) dual-region computed tomography (CT) radiomics model for predicting SLNM in NSCLC. Methods: This retrospective study included NSCLC patients who underwent lung resection and SLNs dissection between January 2017 and December 2020. The radiomic features of the tumor and SLNs were extracted from preoperative CT, respectively. Ninety machine learning (ML) models were developed based on tumor region, SLNs region, and tumor-SLNs dual-region. The model performance was assessed by the area under the curve (AUC) and validated internally by fivefold cross-validation. Results: In total, 202 patients were included in this study. ML models based on dual-region radiomics showed good performance for SLNM prediction, with a median AUC of 0.794 (range, 0.686–0.880), which was superior to those of models based on tumor region (median AUC, 0.746; range, 0.630–0.811) and SLNs region (median AUC, 0.700; range, 0.610–0.842). The ML model, which is developed by using the naive Bayes algorithm and dual-region features, had the highest AUC of 0.880 (range of cross-validation, 0.825–0.937) among all ML models. The optimal logistic regression model was inferior to the optimal ML model for predicting SLNM, with an AUC of 0.727. Conclusions: The CT radiomics showed the potential for accurately predicting SLNM in NSCLC patients. The ML model with dual-region radiomic features has better performance than the logistic regression or single-region models. [ABSTRACT FROM AUTHOR]

A new model is developed to describe the coalescence and breakup between bubbles and inclusions. In this model, the density of bubble attached inclusions is calculated through mass conservation equation. The momentum exchange after breakup or coalescence is derived through momentum conservation equation, which are tracked by discrete particle method (DPM). Three continuous phases (air-slag-steel) are considered in a ladle, and the unsteady turbulent flow is computed through k-ε method. What's more, bubble expansion due to decreasing of hydraulic pressure is also taken into account. Results show that due to the bubble expansion, bubble density is mostly decreased to 0.3 to 0.8 kg/m3. However, after attaching some inclusions, the bubble density significantly rises to 20 to 60 kg/m3. The optimal bubble diameters attaching inclusions are ranged between 1.5 and 10 mm. For traditional slot–slot matched tuyeres (S–S mode), the inclusion removement ratio is 29.48 pct; By comparison, after employing the slot–porous matched tuyeres (S–P mode), the inclusion removements ratio rises to 36.34 pct. The mixing time is also shortened after adopting the S–P mode. The reason for this phenomenon is because the slot tuyere produces a strong asymmetry stream that drives more liquid to flow at the bottom of the ladle. And at the same time, the porous tuyere produces more fine bubbles to entrap more inclusions to the top. Taking advantages of porous and slot tuyeres, the mixing behavior and inclusion removements improves a lot. The result is beneficial for improving ladle refining. [ABSTRACT FROM AUTHOR]

Backgrounds: The narrow genetic basis of cucumber makes breeding of this species difficult. CRISPR/Cas9 system is characteristic of simple design, low cost and high efficiency, which has opened a new path for cucumber functional genetics and the development of cucumber mocular breeding. However, the immature genetic transformation system is the main limiting factor for applying this technology in cucumber. Methods and Results: In this study, a Histochemical β-glucuronidase (GUS) assay was used to analyze the effect of various parameters, including slight scratch of explants, pre-culture time, acetosyringone (AS) concentration, infection time in Agrobacterium solution, and co-culture period on the transformation efficiency. The results showed that the explants slightly scratched after cutting, pre-cultured for 1 day, Agrobacterium bacterial solution containing AS, and 20 min length of infection could significantly increase the GUS staining rate of explants. On this basis, two sequences with high specificity (sgRNA-1 and sgRNA-2) targeted different loci of gene CsGCN5 were designed. The corresponding vectors Cas9-sgRNA-1 and Cas9-sgRNA-2 were constructed and transformed using the above-optimized cucumber genetic transformation system, and three and two PCR positive lines were obtained from 210 and 207 explants, respectively. No sequence mutation at target loci of CsGCN5 was detected in the Cas9-sgRNA-1 transformed three PCR positive lines. However, one mutant line with targeted homozygous change was recognized from the Cas9-sgRNA-2 transformed two PCR positive lines. Conclusion: In this study, 2.4‰ of total explants had directed mutation in the CsGCN5 gene. The results in the present study would be beneficial to further optimize and improve the efficiency of the genetic transformation of cucumber. [ABSTRACT FROM AUTHOR]

Chemical composition and surface quality of ingot are two important technical specifications during electroslag remelting (ESR) of superalloy, which are seriously affected by the physical and chemical properties of the slag. For A-286 superalloy, titanium is required to range from 2.0 to 2.2 wt pct and aluminum is required to range from 0.30 to 0.35 wt pct. Thus, the activity ratio between titania and alumina in slag must be fixed in order to make the reaction 3[Ti] + 2(Al2O3) = 4[Al] + 3(TiO2) be close to thermodynamic equilibrium. This paper focuses on finding a kind of slag with low melting temperature used for producing superalloy containing fixed ratio of titanium and aluminum, which is helpful to improve the surface quality of ESR ingot. In the current study, the thermodynamic equilibrium of 3[Ti] + 2(Al2O3) = 4[Al] + 3(TiO2) between A-286 superalloy and the three slag systems CaF2:CaO:MgO:Al2O3:TiO2 = 47: 25: 3: (25−x): x, CaF2:CaO:MgO:Al2O3:TiO2 = 47: (25−0.5x): 3: (25−0.5x): x, and CaF2:CaO:MgO:Al2O3:TiO2 =47: (25−x): 3: 25: x are studied in an electrical resistance furnace based on Factsage software. After obtaining the equilibrium slag with fixed activity ratio between titania and alumina, the melting temperature of three slag systems are studied by slag melting experimental measurements and phase diagram. Three ESR experiments are carried out by using slag CaF2:CaO:MgO:Al2O3:TiO2 = 47: 25: 3: 16: 9, CaF2:CaO:MgO:Al2O3:TiO2 = 47: 21.3: 3: 21.3: 7.4, and CaF2:CaO:MgO:Al2O3:TiO2 = 47: 19: 3: 25: 6. The results show that the slag systems CaF2:CaO:MgO:Al2O3:TiO2 = 47: 25: 3: (25−x): x, which consists of slag S (CaF2:CaO:MgO:Al2O3 = 47: 25: 3: 25) and slag A (CaF2:CaO:MgO:Al2O3:TiO2 = 47: 25: 3: 15: 10), can not only control the aluminum and titanium contents in superalloy ingot but also have the low-melting-temperature property and improve the surface quality of ESR ingot. [ABSTRACT FROM AUTHOR]

Introduction and hypothesis: The optimal timing for removing urinary catheters is controversial for patients undergoing total hysterectomy. This study aimed to evaluate the optimal time for removing urinary catheters post-hysterectomy. Methods: We searched multiple databases from inception till December 31, 2020, for all randomized trials evaluating the timing of catheter removal following hysterectomy. All studies were evaluated by two investigators independently depending on inclusion and exclusion criteria. Network meta-analysis (NMA) was conducted on the data using Stata 14.0 software. Results: A total of 12 articles involving 1814 patients were ultimately included. This study showed removing urinary catheters 12.1 to 24 h (pooled OR = 2.67; 95% CI, 1.53‑4.67) and 36.1 to 48 h (pooled OR = 8.11;95% CI, 3.78‑17.36) post-hysterectomy increased the risk of urinary tract infection (UTI) compared with immediate catheter removal. Timing of catheter removal in other groups following hysterectomy accompanied a reduced risk of urinary retention (UR) versus immediate catheter removal (P < 0.05). Removal of the urinary catheter from 36.1 to 48 h was most likely to lead to UTI. The maximum SUCRA value of immediate catheter removal after hysterectomy was 99.3% for UR. Catheter removal 24.1 to 36 h after hysterectomy was the best time for preventing UR. Conclusion: Removal of the catheter immediately after hysterectomy may be the optimal time for preventing UTI with increased risk of UR, whereas removal time of the urinary catheters within 6 h post-hysterectomy combined with postoperative urination monitoring might be more beneficial than other removal times following hysterectomy. [ABSTRACT FROM AUTHOR]

In this paper, we consider the possible types of regular maps of order 2 n , where the order of a regular map is the order of automorphism group of the map. For n ≤ 11 , M. Conder classified all regular maps of order 2 n . It is easy to classify regular maps of order 2 n whose valency or covalency is 2 or 2 n - 1 . So we assume that n ≥ 12 and 2 ≤ s , t ≤ n - 2 with s ≤ t to consider regular maps of order 2 n with type { 2 s , 2 t } . We show that for s + t ≤ n or for s + t > n with s = t , there exists a regular map of order 2 n with type { 2 s , 2 t } , and furthermore, we classify regular maps of order 2 n with types { 2 n - 2 , 2 n - 2 } and { 2 n - 3 , 2 n - 3 } . We conjecture that if s + t > n with s < t , then there is no regular map of order 2 n with type { 2 s , 2 t } , and we confirm the conjecture for t = n - 2 and n - 3 . [ABSTRACT FROM AUTHOR]

One of the most challenging aspects of developing high-energy lithium-based batteries is the structural and (electro)chemical stability of Ni-rich active cathode materials at thermally-abused and prolonged cell cycling conditions. Here, we report in situ physicochemical characterizations to improve the fundamental understanding of the degradation mechanism of charged polycrystalline Ni-rich cathodes at elevated temperatures (e.g., ≥ 40 °C). Using multiple microscopy, scattering, thermal, and electrochemical probes, we decouple the major contributors for the thermal instability from intertwined factors. Our research work demonstrates that the grain microstructures play an essential role in the thermal stability of polycrystalline lithium-based positive battery electrodes. We also show that the oxygen release, a crucial process during battery thermal runaway, can be regulated by engineering grain arrangements. Furthermore, the grain arrangements can also modulate the macroscopic crystallographic transformation pattern and oxygen diffusion length in layered oxide cathode materials. Enhancing the stability of positive electrodes at thermally-abused conditions is vital for next-generation lithium-based batteries. Here, the authors report in situ physicochemical characterizations to improve the fundamental understanding of the degradation mechanism in polycrystalline Ni-rich cathodes. [ABSTRACT FROM AUTHOR]

The main failure mode of a wheel–axle assembly, which is an important moving part of rail vehicles, in the interference fit zone is partial fatigue. Given that neither the plane analytical method nor the axisymmetric finite element method can reveal the local and stochastic contact stress concentration at the end of the wheel seat, this study analyzed various factors influencing a machined mating surface and found that the cylindricity error is a key factor in transforming the plane contact into a 3D contact. In addition, the experimental data of the pressing force applied to 60 groups of wheel–axle assemblies were analyzed, and the circumferential contour of the mating surface was found to conform to a beta distribution. Accordingly, a method for obtaining random interpolation points on the circumferential contour was proposed. To ensure the continuity of the mating surface, the circumferential Hermite interpolation method and the axial cubic interpolation method were employed, and the contact surface with random characteristics was modeled. Based on the random ergodicity of the mating surface, a small-sample 3D finite element model of a wheel–axle assembly was established using the random cylindricity error, and a calculation method for the 3D contact stress was proposed. Taking the RE2B axle of railway locomotive as an example, compared with the axisymmetric method, the inhomogeneity analysis of the contact stress of the small-sample model proposed in this paper could help explain the problem of local stress concentration at the end of the wheel seat. The analysis results showed that the maximum stress of the 3D model based on the cylindricity is greater than that of the axisymmetric model, enabling strength evaluation in the design of wheel–axle assemblies. [ABSTRACT FROM AUTHOR]

Experimental and theoretical studies have been carried out to investigate the effects of slag composition on the MgO·Al2O3 inclusion in ingot during the electroslag remelting (ESR) process with a focus on developing a mass-transfer model to understand the evolution mechanism of MgO·Al2O3 inclusion. H13 die steel was used as the electrode and remelted with two different kinds of slags by using a 30-kg ESR furnace. The inclusion compositions and contents of magnesium, silicon, and aluminum along the axial direction of product ingots were analyzed. On the basis of the unreacted core model as well as the penetration and film theories, the theoretical model developed in this work well elucidates the kinetics of slag–metal-inclusion reactions revealing the mechanism of inclusion evolution during the ESR process. The calculation results obtained from the model agree well with the experimental results. The model indicates that the inclusions of the outer MnS layer, which surrounds the MgO·Al2O3 core in the electrode, are disintegrated and removed during the metal film formation process at the tip of the electrode in the ESR furnace. The more CaO there is in the slag, the higher the aluminum and magnesium in the ingot and the lower the silicon. The concentration of MgO in the MgO·Al2O3 inclusion increases with the increase of CaO/SiO2 in the slag. The aluminum in the electrode has little effect on the MgO·Al2O3 inclusion compositions in the final product ingots. [ABSTRACT FROM AUTHOR]

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How to achieve energy-efficient transmission in radio frequency energy harvesting cognitive radio network (RF-CRN) is of great importance when nodes in CRN are self-maintained. This paper presents a radio frequency (RF) energy harvesting hardware-based underlay cognitive radio network (RH-CRN) structure, where a secondary transmitter (ST) first harvests energy from RF signals source originating from the primary network, and then communicates with a secondary receiver (SR) in underlay mode by using the harvested energy. The total consumed energy by the secondary user (SU) must be equal to or less than the total harvested energy referred to as energy causality constraint, In addition, the ST possesses some initial energy which may be the residual energy from the former transmission blocks, and we consider the energy loss of energy harvesting circuit as a systematic factor as well. Our goal is to achieve the maximum energy efficiency (EE) of the secondary network by jointly optimizing transmitting time and power. To guarantee the quality of service (QoS) of secondary transceiver, a minimum requirement of throughput constraint is imposed on the ST in the process of EE maximization. As the EE maximization is a nonlinear fractional programming problem, a quick iterative algorithm based on Dinkelbach's method is proposed to achieve the optimal resource allocation. Simulation results show that the proposed strategy has fast convergence and can improve the system EE greatly while ensuring the QoS. [ABSTRACT FROM AUTHOR]

For each d ≥ 3 , n ≥ 5 , and k 1 , k 2 , ... , k d - 1 ≥ 2 with k 1 + k 2 + ⋯ + k d - 1 ≤ n - 1 , we show how to construct a regular d-polytope whose automorphism group is of order 2 n and whose Schläfli type is { 2 k 1 , 2 k 2 , ... , 2 k d - 1 } . [ABSTRACT FROM AUTHOR]

Objective: To investigate the natural history of persistent pulmonary pure ground-glass nodules (pGGNs) with deep learning-assisted nodule segmentation.Methods: Between January 2007 and October 2018, 110 pGGNs from 110 patients with 573 follow-up CT scans were included in this retrospective study. pGGN automatic segmentation was performed on initial and all follow-up CT scans using the Dr. Wise system based on convolution neural networks. Subsequently, pGGN diameter, density, volume, mass, volume doubling time (VDT), and mass doubling time (MDT) were calculated automatically. Enrolled pGGNs were categorized into growth, 52 (47.3%), and non-growth, 58 (52.7%), groups according to volume growth. Kaplan-Meier analyses with the log-rank test and Cox proportional hazards regression analysis were conducted to analyze the cumulative percentages of pGGN growth and identify risk factors for growth.Results: The mean follow-up period of the enrolled pGGNs was 48.7 ± 23.8 months. The median VDT of the 52 pGGNs having grown was 1448 (range, 339-8640) days, and their median MDT was 1332 (range, 290-38,912) days. The 12-month, 24.7-month, and 60.8-month cumulative percentages of pGGN growth were 10%, 25.5%, and 51.1%, respectively, and they significantly differed among the initial diameter, volume, and mass subgroups (all p < 0.001). The growth pattern of pGGNs may conform to the exponential model. Lobulated sign (p = 0.044), initial mean diameter (p < 0.001), volume (p = 0.003), and mass (p = 0.023) predicted pGGN growth.Conclusions: Persistent pGGNs showed an indolent course. Deep learning can assist in accurately elucidating the natural history of pGGNs. pGGNs with lobulated sign and larger initial diameter, volume, and mass are more likely to grow.Key Points: • The pure ground-glass nodule (pGGN) segmentation accuracy of the Dr. Wise system based on convolution neural networks (CNNs) was 96.5% (573/594). • The median volume doubling time (VDT) of 52 pure ground-glass nodules (pGGNs) having grown was 1448 days (range, 339-8640 days), and their median mass doubling time (MDT) was 1332 days (range, 290-38,912 days). The mean time to growth in volume was 854 ± 675 days (range, 116-2856 days). • The 12-month, 24.7-month, and 60.8-month cumulative percentages of pGGN growth were 10%, 25.5%, and 51.1%, respectively, and they significantly differed among the initial diameter, volume, and mass subgroups (all p values < 0.001). The growth pattern of pure ground-glass nodules may conform to exponential model. [ABSTRACT FROM AUTHOR]

Deep ultraviolet lasers based on the phenomenon of mode-locking have been used widely in many areas in recent years, for example, in semiconductors, the environment and biomedicine. In the development of a mode-locked deep ultraviolet laser, one of the most important aspects is to optimize the multiple parameters of the complex system. Traditional optimization methods require experimenters with more optimization experience, which limits the wide application of the lasers. In this study, we optimize the deep ultraviolet mode-locked laser system using an online neural network to solve this problem. The neural network helps us control the position of the crystal, the length of the cavity, the position of the focusing lens and the temperature of the frequency doubling crystal. We generate a deep ultraviolet mode-locked laser with a power of 18 mW and a spectral center at 205 nm. This result is greatly improved compared to previous results with the same pump power. This technology provides a universal solution to multiparameter problems in the optimization of lasers. [ABSTRACT FROM AUTHOR]

Experimental and theoretical studies have been carried out to investigate the effects of slag on the alloying elements in ingots during the electroslag remelting (ESR) process with a focus on developing a mass-transfer model to understand the mechanism of slag-metal reaction. Stainless steel 1Cr21Ni5Ti was used as the electrode and remelted with two different kinds of slags using a 50-kg ESR furnace. The contents of sulfur, aluminum, titanium and silicon along the axial direction of the produced ingots were analyzed. On the basis of the penetration and film theories, the theoretical model developed in this work elucidates the kinetics of the slag-metal reaction revealing the mechanism of alloying element transfer during the ESR process. The calculation results obtained from the model agree well with the experimental results. The model indicates that the resultant [O] coming from the desulfurization reaction of (O2−) + [S] = (S2−) + [O] causes the oxidation of alloying elements in steel by [M] + [O] = (MO). The distribution ratio of sulfur LS decreases with the increase of slag temperature in the first slag-temperature-rising period, and the concentration of sulfur in the ingot at the beginning of the ESR process is lower than in the rest of the process because of the combination of the large distribution ratio of sulfur LS and excellent kinetic conditions. The concentration of aluminum along the height of the ingot has an increasing trend in the first slag-temperature-rising period, while it has a decreasing trend in the rest of the process. Two methods can solve this problem: one is starting up the ESR furnace by high temperature molten slag technology and the other is continually adding extra titania into the molten slag in the first slag-temperature-rising period. [ABSTRACT FROM AUTHOR]

Objectives: To predict the recurrence of acute pancreatitis (AP) by constructing a radiomics model of contrast-enhanced computed tomography (CECT) at AP first attack.Methods: We retrospectively enrolled 389 first-attack AP patients (271 in the primary cohort and 118 in the validation cohort) from three tertiary referral centers; 126 and 55 patients endured recurrent attacks in each cohort. Four hundred twelve radiomics features were extracted from arterial and venous phase CECT images, and clinical characteristics were gathered to develop a clinical model. An optimal radiomics signature was chosen using a multivariable logistic regression or support vector machine. The radiomics model was developed and validated by incorporating the optimal radiomics signature and clinical characteristics. The performance of the radiomics model was assessed based on its calibration and classification metrics.Results: The optimal radiomics signature was developed based on a multivariable logistic regression with 10 radiomics features. The classification accuracy of the radiomics model well predicted the recurrence of AP for both the primary and validation cohorts (87.1% and 89.0%, respectively). The area under the receiver operating characteristic curve (AUC) of the radiomics model was significantly better than that of the clinical model for both the primary (0.941 vs. 0.712, p = 0.000) and validation (0.929 vs. 0.671, p = 0.000) cohorts. Good calibration was observed for all the models (p > 0.05).Conclusions: The radiomics model based on CECT performed well in predicting AP recurrence. As a quantitative method, radiomics exhibits promising performance in terms of alerting recurrent patients to potential precautions.Key Points: • The incidence of recurrence after an initial episode of acute pancreatitis is high, and quantitative methods for predicting recurrence are lacking. • The radiomics model based on contrast-enhanced computed tomography performed well in predicting the recurrence of acute pancreatitis. • As a quantitative method, radiomics exhibits promising performance in terms of alerting recurrent patients to the potential need to take precautions. [ABSTRACT FROM AUTHOR]

Objective: In the era of fast track surgery, early and accurately estimating whether postoperative length of stay (p-LOS) will be prolonged after lung cancer surgery is very important, both for patient's discharge planning and hospital bed management. Pulmonary function tests (PFTs) are very valuable routine examinations which should not be underutilized before lung cancer surgery. Thus, this study aimed to establish an accurate but simple prediction tool, based on PFTs, for achieving a personalized prediction of prolonged p-LOS in patients following lung resection. Methods: The medical information of 1257 patients undergoing lung cancer surgery were retrospectively reviewed and served as the training set. p-LOS exceeding the third quartile value was considered prolonged. Using logistic regression analyses, potential predictors of prolonged p-LOS were identified among various preoperative factors containing PFTs and intraoperative factors. A nomogram was constructed and subjected to internal and external validation. Results: Five independent risk factors for prolonged p-LOS were identified, including older age, being male, and ratio of residual volume to total lung capacity (RV/TLC) ≥ 45.0% which is the only modifiable risk factor, more invasive surgical approach, and surgical type. The nomogram comprised of these five predictors exhibited sufficient predictive accuracy, with the area under the receiver operating characteristic curve (AUC) of 0.76 [95% confidence interval (CI) 0.73–0.79] in the internal validation. Also its predictive performance remained fine in the external validation, with the AUC of 0.70 (95% CI 0.60–0.79). The calibration curves showed satisfactory agreements between the model predicted probability and the actually observed probability. Conclusions: Preoperative amelioration of RV/TLC may prevent lung cancer patients from unnecessary prolonged p-LOS. The integrated nomogram we developed could provide personalized risk prediction of prolonged p-LOS. This prediction tool may help patients perceive expected hospital stays and enable clinicians to achieve better bed management after lung cancer surgery. [ABSTRACT FROM AUTHOR]

Tetrapod-shaped zinc oxide (T-ZnO) whiskers were coated with silver by chemical plating (T-ZnO@Ag). T-ZnO(T-ZnO@Ag)/silicone rubber composites were fabricated at a temperature of 165°C and pressure of 15 MPa. The nonlinear conductivity characteristics of T-ZnO (T-ZnO@Ag)/silicone rubber composites with volume fractions of 1 vol.%, 2.4 vol.%, 3.7 vol.%, and 5 vol.% were investigated. The dielectric properties of the composites at frequencies of 0.1 Hz to 10 MHz were analyzed. The conductivity of the T-ZnO/silicone rubber composite increased with the T-ZnO content, while the switching field decreased. Upon the coating of T-ZnO with Ag, the nonlinear characteristics of the T-ZnO@Ag/silicone rubber composite significantly enhanced. The nonlinear coefficient reached 10.95 at the filler content of 2.4 vol.%. The percolation threshold of T-ZnO fillers is significantly lower than that of spherical ZnO fillers. Percolation threshold and Schottky barrier effect were utilized to explain the nonlinear electrical properties. [ABSTRACT FROM AUTHOR]

Key message: We identified two curly-leaf (cul) mutants in cucumber. Map-based cloning revealed that both mutants are due to allelic mutations in the CsPHB gene, a homolog of the Arabidopsis PHABULOSA which encodes a class III homeodomain-leucine zipper (HD-ZIP III) transcription factor.Abstract: Leaf rolling is an important agronomic trait in crop breeding. Moderate leaf rolling minimizes shadowing between leaves, leading to improved photosynthetic efficiency. Although a number of genes controlling rolled leaf have been identified from rice and other plant species, none have been mapped or cloned in cucurbit crops. In this study, we identified and characterized two curly leaf (cul) mutants, cul-1 and cul-2 in cucumber. With map-based cloning, we show that cul-1 and cul-2 are allelic mutations and CsPHB (Csa6G525430) was the candidate gene for both mutants. The CsPHB gene encoded a class III homeodomain-leucine zipper (HD-ZIP III) transcription factor. A single non-synonymous mutation in the fourth and fifth exons of the CsPHB was responsible for the cul-1 and cul-2 mutant phenotypes, respectively. The single-nucleotide substitutions in cul-1 and cul-2 were both located in cs-miRNA165/166 complementary sites of CsPHB. The expression level of CsPHB gene in multiple organs of cul-1 and cul-2 mutants was higher than that in the wild type, while the expression of cs-miRNA165/166 in the two genotypes showed the opposite trend. We speculate that disruption of the binding between the mutant allele of CsPHB and cs-miRNA165/166 leads to the curly-leaf phenotype. This is the first report to clone and characterize the CsPHB gene in the family Cucurbitaceae. Taken together, these results support CsPHB as an important player in the modulation of leaf shape development in cucumber. [ABSTRACT FROM AUTHOR]

The grounded-wire transient electromagnetic (TEM) surveying is often performed along the equatorial direction with its observation lines paralleling to the transmitting wire with a certain transmitter-receiver distance. However, such method takes into account only the equatorial component of the electromagnetic field, and a little effort has been made on incorporating the other major component along the transmitting wire, here denoted as axial field. To obtain a comprehensive understanding of its fundamental characteristics and guide the designing of the corresponding observation system for reliable anomaly detection, this study for the first time investigates the axial electric field from three crucial aspects, including its decay curve, plane distribution, and anomaly sensitivity, through both synthetic modeling and real application to one major coal field in China. The results demonstrate a higher sensitivity to both high- and low-resistivity anomalies by the electric field in axial direction and confirm its great potentials for robust anomaly detection in the subsurface. [ABSTRACT FROM AUTHOR]

Experimental and theoretical studies have been carried out to investigate the effects of the slag on desulfurization during the electroslag remelting (ESR) process with a focus of developing a mass transfer model to understand the mechanism of desulfurization. Stainless steel 1Cr21Ni5Ti was used as the electrode and remelted with two different kinds of slags using a 50-kg ESR furnace. The contents of sulfur along the axial direction of product ingots were analyzed. It was found that the sulfur content of 350 ppm in the electrode is reduced to 71 to 95 ppm in the ingot by remelting with the slag containing 5 wt pct of CaO, and lowered more to 47 to 59 ppm with another slag having 20 wt pct CaO. On the basis of the penetration and film theories, the theoretical model developed in this work well elucidates the kinetics of desulfurization revealing the mechanism of sulfur transfer during the ESR process. The calculation results obtained from the model agree well with the experimental results. The model indicates that when sulfur content in electrode is given, there is a corresponding minimum value of sulfur content in the ingot due to the kinetics limit. This lowest sulfur content cannot be further reduced even with increasing L (sulfur distribution coefficient between metal and slag phases) or decreasing sulfur content in the slag. Constant addition of extra amount of CaO to the molten slag with the increase of sulfur content in the slag during the remelting process can improve the macrosegregation of sulfur distributed along the axial direction of ESR ingots. Since the rate-determining steps of the sulfur mass transfer lie in the metal phase, adding calcium as deoxidizer can change mass transfer of sulfur and thus promote desulfurization further during the ESR process. [ABSTRACT FROM AUTHOR]

Many factors influence the chemical composition in electroslag remelting (ESR) steel, including atmosphere in crucible, melting rate, slag composition, deoxidation, and so on. Fluoride-based slag, which is exposed to liquid metal directly, influences the chemical composition of ESR ingots to a large extent. The present paper focuses on the effect of slag on the titanium, silicon, and aluminum contents in ingots based on the interaction of the slag and metal. In present work, superalloy of GH8825 and several slags containing different CaO contents have been employed for investigating the effect of slag on titanium, silicon, and aluminum contents in an electrical resistance furnace under argon atmosphere. Results indicate that the higher CaO content in slag has better capacity for avoiding loss of titanium caused by the reaction of titanium with silica in slag, especially in case of remelting superalloy with high titanium and low silicon content. The CaO has a great effect on the activities of TiO, SiO, and AlO. Thermodynamic analysis is applied to investigate the CaO behavior. Based on the ion and molecule coexistence theory of slag, activity model is established to calculate the activities of components containing titanium, silicon, and aluminum elements in a six-component slag consisting of CaO-CaF-AlO-SiO-TiO-MgO. The components containing titanium, silicon, and aluminum in slag are mainly CaO·TiO, 2CaO·SiO, CaO·SiO, CaO·AlO, and MgO·AlO. With the increase of CaO mass fraction in slag, the activity coefficient of SiO decreases significantly, whereas slightly change happens for AlO. As a result, the $$ \lg ({{\gamma_{{{\text{SiO}}_{2} }} } \mathord{\left/ {\vphantom {{\gamma_{{{\text{SiO}}_{2} }} } {\gamma_{{{\text{TiO}}_{2} }} }}} \right. \kern-0pt} {\gamma_{{{\text{TiO}}_{2} }} }}) $$ decreases with increasing CaO content, which is better for preventing loss of titanium caused by the reaction of titanium with silica in slag. The slag with high CaO and appropriate TiO content is suitable for electroslag remelting of GH8825. [ABSTRACT FROM AUTHOR]

Droplet formation and departure from an electrode tip affect the temperature distribution in liquid slag and a molten steel pool, as well as the removal of nonmetallic inclusions in the electroslag remelting process. In this article, magneto-hydrodynamics modules coupled with a volume of fluid (VOF) model (as described in VOF model theory) for tracking phase distribution have been employed to develop the electrode fusion model and to investigate formation and departure of a droplet from the electrode tip. Subsequently, the remelting rate and molten steel pool have been achieved based on the electrode fusion model. Results indicate that a droplet can increase the flow rate of liquid slag, especially the region of droplet fall through the slag pool; yet it has little impact on the flow distribution. Asymmetric flow can take place in a slag pool due to the action of the droplet. The depth of the molten steel pool increases in the presence of droplets, but the width of the mushy zone decreases. In addition, the shape of the electrode tip is not constant but changes with its fusion. The remelting rate is calculated instead of being imposed in this work. The development of the model supports further understanding of the process and the ability to set the appropriate operating parameters, especially for expensive and easy segregation materials. [ABSTRACT FROM AUTHOR]

A better understanding of droplet formation and dripping behavior would be useful in the efficient removal of impurity elements and nonmetallic inclusions from liquid metals. In the present work, we developed a transparent experimental apparatus to study the mechanisms of droplet formation and the effects of filling ratio on droplet behavior during the electroslag remelting (ESR) process. A high-speed camera was used to clearly observe, at small time scales, the droplet formation and dripping phenomenon at the slag/metal interface during a stable ESR process. The results illustrate that a two-stage process for droplet formation and dripping occurs during the ESR process and that the droplet diameter exhibits a parabolic distribution with increasing filling ratio because of the different shape and thermal state of the electrode tip. This work also confirms that a relatively large filling ratio reduces electricity consumption and improves ingot quality. [ABSTRACT FROM AUTHOR]

Traditional TEM study mainly focuses on the generation and application of the TE field using a loop or grounded-wire source; but in recent decades, lots of efforts have been made for implementation of the TM field and even the integration of the TE field with the TM one into anomaly detection in the subsurface. However, no applicable principles have been proposed for selecting the optimal electromagnetic field for various subsurface targets. The transient electromagnetic (TEM) fields generated from grounded-wire source consist of the TE-mode response (current-carrying wire), the TE-TM mode response (grounding ends) and the combined TEM-mode response (current-carrying wire and grounding ends). This study performs a comparison of TE/TE-TM/TEM fields by generating them from grounded-wire source and testing their distribution characteristics, detection depth, and sensitivity to anomalies, using both synthetic 1D model and two field surveys in China. The comparisons demonstrate that, the detection depth of the TE-TM field is smaller than those of both the TE and combined TEM fields. Meanwhile, for electric field, the TE-TM response provides a better detection than the TEM one, but with an uneven distribution. Therefore, the TE-TM electric field requires well-designed arrangements of receiving positions when applied to real projects. For the magnetic field, the TEM response has the best detection capability compared to the TE and TE-TM ones, but is least sensitive to layer thickness and resistivity, especially for an embedded layer with low resistivity. [ABSTRACT FROM AUTHOR]

Many factors influence the non-metallic inclusions in electroslag steel including furnace atmosphere and inclusions' content in the consumable electrode, slag amount and its composition, power input, melting rate, filling ratio, and so on. Fluoride containing slag, which influences the non-metallic inclusions to a great extent, has been widely used for the electroslag remelting process. The current paper focuses on the effect of fluoride containing slag on the inclusions in electroslag ingots based on the interaction of the slag-metal interface and electroslag remelting process. In this work, die steel of CR-5A and several slags have been employed for investigating the effect of slag on inclusions in an electrical resistance furnace under argon atmosphere in order to eliminate the effect of ambient oxygen. Specimens were taken at different times for analyzing the content, dimensions, and type of non-metallic inclusions. Results of quantitative metallographic analysis indicate that a multi-component slag has better capacity for controlling the amount of inclusions; especially protective gas atmosphere has also been adopted. The findings of inclusions in electroslag steel by SEM-EDS analysis reveal that most non-metallic inclusions in electroslag steel are MgO-AlO inclusions for multi-component slags, but it is AlO inclusions when remelting using conventional 70 wt pct CaF-30 wt pct AlO slag. The maximal inclusions' size using multi-component slags is less than that using conventional binary slag. Small filling ratio as well as protective gas atmosphere is favorable for controlling the non-metallic inclusions in electroslag steel. All the results obtained will be compared to the original state inclusions in steel, which contribute to choice of slag for electroslag remelting. [ABSTRACT FROM AUTHOR]

The formation of zinc ferrite (ZnFeO) during the oxidative roasting of zinc sulfide concentrates can lead to a reduced recovery of zinc during the subsequent zinc treatment process (leaching). To improve zinc recovery in leaching and minimize the environmental aspects influenced by the presence of ZnFeO, a selective reduction roasting process is proposed in this study by transforming ZnFeO into ZnO and FeO under a gaseous atmosphere corresponding to 10% CO and 90% CO at between 700°C and 800°C. Accordingly, roasting tests were carried out and the roasted products were characterized by x-ray fluorescence, x-ray diffraction, scanning electron microscopy, laser particle size analysis technique, and vibrating sample magnetometry techniques, as well as by bulk chemical analysis. The results show that the calcine particles grew rapidly in size after roasting at 750°C, and the specific magnetic induction increased from 0.42 emu/g to 11.36 emu/g due to the formation of FeO. After roasting at 800°C, the particles tended to become smaller while the specific magnetic induction dropped to 10.12 emu/g due to the formation of FeZnO. The remaining part of the zinc present as FeZnO caused a lower zinc yield in the subsequent leaching process. Therefore, the formation of FeZnO is the main factor influencing the separation of zinc and iron. Graphical Abstract: The Graphical abstract is list as follows: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The full-length cDNA sequence of the MLO gene was cloned via SMART-RACE-PCR from muskmelon ( Cucumis melo L.), and was designated as CmMLO2 (GenBank Accession No. FJ713542). The gene is 1,710 bp long and encodes a 570-amino acid peptide with a seven-transmembrane domain topology, and is a typical transmembrane protein. Localization analysis in onion epidermal cells showed that CmMLO2-GFP is localized in the plasma membrane. The expression of CmMLO2 gene was analyzed in melon leaf infected with powdery mildew using a quantitative RT-PCR and it was found that CmMLO2 was mainly expressed in melon leaves in a no-tissue-specific pattern. Moreover, CmMLO2 may play a crucial role in the pathogenesis of powdery mildew. [ABSTRACT FROM AUTHOR]

Ultrafast electron-based coherent radiation sources, such as free-electron lasers (FELs), ultrafast electron diffraction (UED) and Thomson-scattering sources, are becoming more important sources in today's ultrafast science. Photocathode laser is an indispensable common subsystem in these sources that generates ultrafast electron pulses. To fully exploit the potentials of these sources, especially for pump-probe experiments, it is important to achieve high-precision synchronization between the photocathode laser and radio-frequency (RF) sources that manipulate electron pulses. So far, most of precision laser-RF synchronization has been achieved by using specially designed low-noise Er-fibre lasers at telecommunication wavelength. Here we show a modular method that achieves long-term (>1 day) stable 10-fs-level synchronization between a commercial 79.33-MHz Ti:sapphire laser oscillator and an S-band (2.856-GHz) RF oscillator. This is an important first step toward a photocathode laser-based femtosecond RF timing and synchronization system that is suitable for various small- to mid-scale ultrafast X-ray and electron sources. [ABSTRACT FROM AUTHOR]