Search

Wheat hybrids have been widely demonstrated to have remarkable heterosis or hybrid vigor in increasing yield potential and stability since the 1960s. Two-line hybrid wheat can achieve higher yields than local varieties, especially in marginal environments. However, the commercial application of hybrid wheat is hindered by higher seed costs, primarily due to lower yields in hybrid seed production. Stigma exsertion has been verified as a decisive factor in increasing rice’s hybrid seed yield, but more investigation is needed in hybrid wheat breeding and production. In this study, four thermo-photo-sensitive genic male sterile lines, including K41S, K64S, K66S, and K68S, with different stigma exsertion rates (SERs) were used to compare the differences in floral architecture relative to stigma exsertion over two growing seasons. The results revealed that the K41S and K64S exhibited a relatively higher SER at 21.87% and 22.81%, respectively. No exserted stigma was observed in K66S, and K68S had an SER of only 0.82%. This study found that the stigma length, glume width and the length–width ratio of the glume were significantly correlated with the SER, with correlation coefficients of 0.46, −0.46 and 0.60, respectively. Other stigma features such as the branch angle, stretch width and hairbrush length, as well as the glume length, also had a weakly positive correlation with SER (r = 0.09–0.27). For K41S and K64S, the SER was significantly affected by the differences in the stigma branch angle and stigma stretch width among florets. A cross-pollination survey showed that the out-crossing ability of florets with an exserted stigma was about three times as high as that of florets with a non-exserted stigma. As a result, the stigma-exserted florets that accounted for 21.87% and 22.81% of the total florets in K41S and K64S produced 46.80% and 48.53% of the total cross-pollinated seeds in both sterile lines. These findings suggest that a longer stigma combined with a slender glume appears to be the essential floral feature of stigma exsertion in sterile wheat lines. It is expected that breeding and utilizing sterile lines with a higher SER would be a promising solution to cost-effective hybrid wheat seed production.

Background and objective Lung large cell neuroendocrine carcinoma (LCNEC) is a rare and highly malignant lung tumor with a poor prognosis. Currently, most research on LCNEC is based on retrospective studies and lacks validation in the real world. The study aims to identify independent risk factors and establish and validate a predictive model for the prognosis of LCNEC. Methods Patient data were extracted from Surveillance, Epidemiology, and End Results (SEER) and our department's hospitalization records from 2010 to 2015 and 2016 to 2020, respectively. Kaplan-Meier analysis was used to evaluate overall survival (OS). OS is defined as the time from diagnosis to death or last follow-up for a patient. Univariate and multivariate Cox regression analyses were performed to identify significant prognostic factors and construct a Nomogram for predicting the prognosis of LCNEC. Results In total, 1892 LCNEC patients were included and divided into a training cohort (n=1288) and two validation cohorts (n=552, n=52). Univariate Cox regression analysis showed that age, gender, primary tumor site, laterality, T stage, N stage, M stage, surgery, and radiotherapy were factors that could affect the prognosis of LCNEC patients (P

ABSTRACTObjective: Diffuse Large B-Cell Lymphoma (DLBCL) is a common and frequently occurring subtype of Non-Hodgkin Lymphoma (NHL). The effective treatment and prognosis of DLBCL are still urgently needed to be explored. This article aims to shed light on the connection between DLBCL survival and NR3C1 expression levels. Methods: First, we divided the 952 DLBCL patients into an NR3C1 high-expression group and an NR3C1 low-expression group and compared the baseline characteristics of the two groups. Second, we used multivariate analysis to predict the dependent variable for age, pathology, ECOG score, lactate dehydrogenase (LDH) ratio, and NR3C1 expression level. Finally, we analyzed the progression-free survival (PFS) and overall survival rate (OS) of DLBCL patients with high or low NR3C1 expression. Results: DLBCL patients with high NR3C1 expression had a better prognosis than those with low NR3C1 expression (OS, P

The construction of Z-scheme heterostructures is of great significance for realizing efficient photocatalytic water splitting. Here, the authors report an interfacial chemical bond and internal electric field modulated Z-Scheme Sv-ZnIn2S4/MoSe2 photocatalyst for efficient hydrogen evolution.

While H2 could be a renewable fuel, the large-scale preparation of cheap, active electrocatalysts for large-scale production remains a challenge. Here, authors use a rapid, solvent-free microwave pyrolysis method to synthesize nanostructured catalysts for large-scale industrial H2 production.

The design of nanostructured catalysts plays a key role in the electrocatalytic redox reaction performances. Here, authors prepared uniform and small-sized high-entropy alloy PtNiFeCoCu nanoparticles that showed improved activities for H2 evolution methanol oxidation reactions.

Abstract Background Two-line hybrid wheat system using thermo-photo sensitive genic male sterility (TPSGMS) is currently the most promising approach for wheat heterosis utilization in China. However, during past 20 years only few TPSGMS lines were developed in hybrid wheat breeding, which has been the main limiting factor to create heterotic hybrids. Application of doubled haploid (DH) breeding provides a useful strategy to efficiently develop practically usable TPSGMS lines. Results F1s and selected F2 and F3 sterile plants of eight crosses made from two commercial TPSGMS lines were used to produce DH lines. We developed a total of 24 elite DH sterile lines with stable sterility, good outcrossing and yield potential, resistance to yellow rust and powdery mildew, as well as desirable plant height (50–60 cm). These DH lines were developed within 4 years through at least 1 year of evaluation. The stability of male sterility was confirmed for most (20/24) of these elite DH sterile lines by multiple tests in two or 3 years. These lines are expected to be used in hybrid wheat breeding. The percentage of elite lines developed from the tested DH lines produced from filial generations was in the order of F2 > F3 > F1. Conclusions We demonstrate that coupling DH techniques with conventional breeding is an efficient strategy for accelerating the development of more practical wheat TPSGMS lines. Generation of DHs from F2 generation appeared to be the better choice considering the balance of shortening breeding time and overall breeding efficiency.

In this paper, a mold electromagnetic stirring (M-EMS) model was established to investigate the behavior of M-EMS for round bloom castings under different conditions, and an electromagnetic-flow-heat transfer-solidification coupling model was established to explore the problem of eccentric stirring for various formats of round blooms. The results show that the magnetic flux density decreased with the increase in the current frequency, but the electromagnetic torque increases first and then decreases with it, and the same structure of M-EMS for round blooms has the same optimal current frequency at any current intensity. The electromagnetic torque and electromagnetic force both increase as a quadratic function of the current intensity, and the electromagnetic torque, which drives the steel flow, can directly characterize the real M-EMS performance. The mold copper tube has a significant magnetic shielding effect on M-EMS, the stirring intensity decreases rapidly as the tube thickness increases, and the optimal stirring frequency decreases as well. In fact, the deviation between the stirrer center and the geometric center of the strand can result in the eccentric stirring phenomenon. When blooms with a section size of Φ350 mm are produced by Φ650 mm SMS-Concast casting machine, the upper region of the inner arc side and the lower region of the outer arc side are subject to a stronger washing effect, which makes the temperature of the inner and outer arcs show alternating differences. The jet flow from the five-port nozzle can suppress the difference in initial solidification symmetry between the inner and outer arcs of round blooms caused by eccentric stirring. This paper reveals the magnetic shielding effect of the mold copper tube and the magnetic field loss of the air between the stirrer and the inner and outer arcs of the copper, which lead to the stirring intensity and the eccentric stirring phenomenon.

Using styrene as a proxy for VOCs, a new method was developed to remove styrene gas in nitrogen atmospheres. The effect on the styrene removal efficiency was explored by varying parameters within the continuum dynamic experimental setup, such as ferrous ion concentration, hydrogen peroxide concentration, and pH values. The by-products are quantized by a TOC analyzer. The optimal process conditions were hydrogen peroxide at 20 mmol/L, ferrous ions at 0.3 mmol/L and pH 3, resulting in an average styrene removal efficiency of 96.23%. In addition, in this study, we construct a BAS-BP neural network model with experimental data as a sample training set, which boosts the goodness-of-fit of the BP neural network and is able to tentatively predict styrene gas residuals for different front-end conditions.

Localization is a keystone for a robot to work within its environment and with other robots. There have been many methods used to solve this problem. This paper deals with the use of beacon-based localization to answer the research question: Can ultra-wideband technology be used to effectively localize a robot with sensor fusion? This paper has developed an innovative solution for creating a sensor fusion platform that uses ultra-wideband communication as a localization method to allow an environment to be perceived and inspected in three dimensions from multiple perspectives simultaneously. A series of contributions have been presented, supported by an in-depth literature review regarding topics in this field of knowledge. The proposed method was then designed, built, and tested successfully in two different environments exceeding its required tolerances. The result of the testing and the ideas formulated throughout the paper were discussed and future work outlined on how to build upon this work in potential academic papers and projects.

The relationship between the popular hot charging associated surface crack sensitivity and the charging temperature was studied from the view of phase transformation. The austenite reversion with various charging temperatures was investigated through the thermal simulation experiments. And a two-dimensional representative volume element model was constructed to analyze the crack sensitivity related to microstructures. Compared to cold charging reversion, with the residual austenite in starting microstructure, the kinetics of hot charging reversion is slightly accelerated and the reversion behavior is changed. As the charging temperature increases, the austenite nucleation-growth from pearlite and ferrite grain boundaries are suppressed, while the austenitization through the growth of residual austenite is enhanced. The change of transformation behavior facilitates the formation of ferrite film during reversion through the morphological influence of austenitization modes. With the increasing of charging temperature, the film-like morphology of the evolved ferrite intensifies, especially in the two-phase temperature range. Consequently, the calculated crack sensitivity index rises sharply from 0.0006 to 0.029 when the charging temperature increases from Ar1 to Ar3 temperature, which is agreeable with the statistical production data. Additionally, it was observed that the incomplete γ → α → γ transformation cannot bring an effective austenite grain refining for the present steel.

With requirements to improve life quality, smart homes, and healthcare have gradually become a future lifestyle. In particular, service robots with human behavioral sensing for private or personal use in the home have attracted a lot of research attention thanks to their advantages in relieving high labor costs and the fatigue of human assistance. In this paper, a novel force-sensing- and robotic learning algorithm-based teaching interface for robot massaging has been proposed. For the teaching purposes, a human operator physically holds the end-effector of the robot to perform the demonstration. At this stage, the end position data are outputted and sent to be segmented via the Finite Difference (FD) method. A Dynamic Movement Primitive (DMP) is utilized to model and generalize the human-like movements. In order to learn from multiple demonstrations, Dynamic Time Warping (DTW) is used for the preprocessing of the data recorded on the robot platform, and a Gaussian Mixture Model (GMM) is employed for the evaluation of DMP to generate multiple patterns after the completion of the teaching process. After that, a Gaussian Mixture Regression (GMR) algorithm is applied to generate a synthesized trajectory to minimize position errors. Then a hybrid position/force controller is integrated to track the desired trajectory in the task space while considering the safety of human-robot interaction. The validation of our proposed method has been performed and proved by conducting massage tasks on a KUKA LBR iiwa robot platform.

This paper developed a character recombination technology based on dynamic movement primitive (DMP) segmentation using verbal command on a Baxter robot platform. Movements are recorded from a human demonstrator. The operator physically guides the Baxter robot to perform the movements for five times. This training data set is also utilized for playback process. Subsequently, the dynamic time warping is employed to pre-treat the data. The DMP is used to model and generalize every single movement. Gaussian mixture model is used to generate multiple patterns after the teaching process. Then the Gaussian mixture regression algorithm is applied to reduce the position errors in 3D space after the generation of a synthesized trajectory. A remote PC is used to control the command of Baxter to record or playback any trajectories via user datagram protocol (UDP) by typing commands in a text file. In addition, Dragon NaturalSpeaking software is used to transfer the voice data to text data. This proposed approach is tested by performing a Chinese character writing task with a Baxter robot, where different Chinese characters are written by teaching only one character.

In order to reduce the fire risk of rigid polyurethane foams (RPUF), three kinds of zeolitic imidazolate frameworks (ZIFs) were prepared. The results of Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM and X-ray diffraction (XRD) showed that ZIFs were successfully prepared. The combustion test results showed that the heat and smoke production of the composite containing ZIFs was obviously reduced. In particular, the peak heat release rate (PHRR) of ZIF-8/RPUF decreased from 740.85 kW/m2 (Ref. RPUF) to 489.56 kW/m2, while the PHRR of ZIF-7/RPUF and ZIF-11/RPUF is 598.39 and 583.36 kW/m2, respectively. The addition of ZIFs improved the thermostability of the composite. The T50% of ZIF-8/RPUF, ZIF-7/RPUF and ZIF-11/RPUF increased to 364, 382 and 380 °C, respectively. The maximum light absorption of ZIF-7/RPUF and ZIF-11/RPUF was about 88%, which is higher than that of ZIF-8/RPUF (75%). The results of Raman spectroscopy showed that the ID/IG value of Ref. RPUF is 2.96, while the ID/IG value of ZIFs/RPUF reduces to less than 2.80. The main mechanism of ZIFs for reducing the fire risk of RPUF was the catalysis and incarbonization of ZIFs during combustion based on the results of thermogravimetric analysis and Raman spectroscopy of char residue.

To improve sulfuric acid recovery from sodium sulfate wastewater, a lab-scale bipolar membrane electrodialysis (BMED) process was used for the treatment of simulated sodium sulfate wastewater. In order to increase the concentration of sulfuric acid (H2SO4) generated during the process, a certain concentration of ammonium sulfate solution was added into the feed compartment. To study the influencing factors of sulfuric acid yield, we prepared different concentrations of ammonium sulfate solution, different feed solution volumes, and different membrane configurations in this experiment. As it can be seen from the results, when adding 8% (NH4)2SO4 into 15% Na2SO4 under the experimental conditions where the current density was 50 mA/cm2, the concentration of H2SO4 increased from 0.89 to 1.215 mol/L, and the current efficiency and energy consumption could be up to 60.12% and 2.59 kWh/kg, respectively. Furthermore, with the increase of the volume of the feed compartment, the concentration of H2SO4 also increased. At the same time, the configuration also affects the final concentration of the sulfuric acid; in the BP-A-C-BP (“BP” means bipolar membrane, “A” means anion exchange membrane, and “C” means cation exchange membrane; “BP-A-C-BP” means that two bipolar membranes, an anion exchange membrane, and a cation exchange membrane are alternately arranged to form a repeating unit of the membrane stack) configuration, a higher H2SO4 concentration was generated and less energy was consumed. The results show that the addition of the double conjugate salt is an effective method to increase the concentration of acid produced in the BMED process.

Based on the Maxwell’s equations, a finite element model is established to study the characteristics of electromagnetic field in the mold of billet and bloom continuous casting with electromagnetic stirring (M-EMS). A novel integral method for calculating electromagnetic torque is proposed to evaluate the stirring intensity of stirrer. In order to verify the accuracy of the model, a well-designed electromagnetic torque detecting device is fabricated. The predicted value of electromagnetic torque and magnetic flux density are consistent with the measured data. The optimum frequency is determined by the maximal electromagnetic torque of the strand. The effect of stirring current intensity and different stirrer positions along the length of mold on the electromagnetic field has been studied numerically. The results show that the optimum frequency is smaller when the copper tube of the mold is thicker and the section size is bigger. Besides, the electromagnetic torque of the strand is a quadratic function of the running current intensity. Moreover, the installation position of stirrer strongly affects the prediction of electromagnetic field distribution, further influencing the optimum frequency and the electromagnetic torque of strand.

Solar steam generation to generate steam through solar light-driven surface evaporation can be an attractive methodology that utilizes green and inexhaustible solar energy to generate water steam and fresh water with superior efficiency. However, some drawbacks of the current photothermal conversion materials such as complicated fabrication process, high cost, and low salt tolerance often heavily restrict their wide applications. Herein, a green and low-cost method is designed and developed for constructing a free-standing, elastic, and highly tough 3D network of carbon nanotubes (CNTs) and MXene through an efficient "egg-box" coordination mechanism in only one step for high-efficiency water evaporation. When the mass ratios of MXene and CNTs are designed at 1:1.5 and cross-linked with sodium alginate and CaCl2, the obtained MCS-3 shows the most excellent light absorption and hydrophilicity, leading to the best evaporation rate of 1.644 kgm-2 h-1, and the highest photothermal conversion efficiency of 96%. Moreover, subject to different harsh environments and durability tests, MCS-3 also shows desired structural stability and evaporation performance. As demonstrated by its extraordinary photothermal evaporation properties, MCS-3 can envision a wide range of commercial applications covering wastewater purification, brine seawater, desalination, etc. [ABSTRACT FROM AUTHOR]

The flocculating ability of the flocculant directly affects the quality of the treated water. Poly-ferric sulfate flocculant (PFS) is a commonly used flocculant. The purpose of this study is to use the electrodialysis process to concentrate the solution and the bipolar membrane electrodialysis to dissociate water to produce acid and alkali to achieve the preparation of poly-ferric sulfate flocculant. The effects of current density, feed flow rate, and sulfuric acid addition on the quality of PFS were tested. Experiments have proved that the increase of current density is beneficial to the increase of PFS alkalinity and turbidity removal rate, and at the same time energy consumption will be reduced. When the current density is 30 mA/cm2, the alkalinity reaches a maximum of 21.04% and the energy consumption is 1.52 kW·h (kg H2SO4). When the current density is 20 mA/cm2, the turbidity removal rate reaches a maximum of 94.23% and the energy consumption is 2.46 kW·h (kg H2SO4). In addition, the solid PFS was subjected to scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy tests after vacuum drying to further confirm the structure of the PFS. [ABSTRACT FROM AUTHOR]