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In this paper, we propose a new 4D segmentation formulation, aiming to improve the temporal consistency of adults' brain tissue segmentation. In our method, tissue segmentation result is represented by the membership functions of the tissues, which are derived as a result of minimizing energy in a fuzzy C-means (FCM) framework. We first introduce a variational formulation with a temporal consistency constraint on the membership functions, then convert the constraint to a vector-valued function from which the membership functions are directly computed according to an analytically defined mapping. These vector-valued functions capture the bias field and intensity means of each tissue addressing the temporal variation in intensity inhomogeneities and the intensity means of the images. The effectiveness is demonstrated on the Baltimore Longitudinal Study of Aging (BLSA) benchmark dataset. Our method takes few parameters which are easy to tune and achieves 96.4% of TC factor for gray matter, 98.1% of TC factor for white matter, significantly superior to the compared methods on this research line.

When an input terminal is connected to a solar panel with a low voltage level and large power range fluctuation, a Boost type CLLC converter controlled by fixed frequency pulse width modulation (PWM) reduces the utilization of PV electric energy, and the synchronous drive of the secondary side and primary side ensures that the converter operates with low efficiency when the duty cycle is shifted by 0.5. To maximize the utilization of photovoltaic (PV) energy in a PV power generation system and improve the conversion efficiency, this paper studies a Boost CLLC converter with high gain and soft switching controlled by PWM-pulse frequency modulation (PFM) hybrid modulation for PV power generation. By controlling the duty cycle and switching frequency of the primary MOSFETs, the converter can stabilize the output voltage while tracking the PV maximum power point. Under such a hybrid control, the resonant gain of the converter is greater than 1, the voltage gain is large, one of the MOSFETs at the primary side is in a zero-voltage-switching-open (ZVS-ON) state, two diodes are used to realize zero-current-switching (ZCS) soft switching on the secondary side, and the efficiency of the converter is high. In addition, this paper studies the phenomenon of backflow power in the resonant circuit and the influence of a change in the switching frequency on the magnitude of the backflow power. Finally, a 500W experimental prototype was constructed to verify the accuracy of the theoretical analysis and the feasibility of the control method.

Accurate prediction of the remaining useful life (RUL) of lithium-ion batteries can ensure the normal and effective operation of power systems using lithium-ion batteries. However, how to select battery prediction parameters through scientific methods and how to accurately predict battery RUL values under high and low temperature conditions are still a huge challenge. Thus according to the technique for order preference by similarity to ideal solution (TOPSIS) based on information entropy, improved particle swarm optimization (PSO) and moving average filter(MAF), a novel data-driven method for predict lithium-ion batteries' RUL is proposed. The TOPSIS method based on information entropy is proposed to select the best degradation parameters; a sliding average low-pass filter is used to solve the capacity regeneration and noise problem of the battery experimental data; the improved PSO algorithm is presented to predict the battery RUL accurately. Based on the batteries experimental data from NASA and University of Maryland, we have done many simulation experiments on parameters selection and RUL accuracy comparisons among several data-driven methods. The experimental results shows:(1) compared with the other prediction methods without degradation parameters selection, the proposed method with TOPSIS and MAF filtering is more accurate;(2) our proposed algorithm has higher prediction accuracy and use less training data than other data-driven algorithms;(3) this method has high prediction accuracy under both the high and low temperature conditions.

To repair leaking pipelines for oil, natural gas and other dangerous media, a kind of pipeline sealing robot is proposed. The device is mainly divided into a robot drive unit, connection unit, and blocking unit. The robot drive unit is used to pull the blocking unit, allowing it to move in the pipeline. The connection unit is used to connect the robot drive unit and the blocking unit. The blocking unit is used to complete the repair at the leakage point. When the robot operates, the drive unit drags the blocking device to the pipeline leakage location, and the front camera can detect the size and shape of the leakage hole. The sealing unit is located at the leakage point, an airbag is inflated, and the adhesive in it is used to seal and repair the leak. Two performance indices (climbing performance and curve passing performance) are evaluated when the robot drive unit is walking. A 3D model of the robot is established, and the performance index of the robot is simulated and analyzed using virtual prototype technology. An experimental platform is built for verification. The conclusions are as follows: (1) A spring with a 13 N/mm rigidity yielded the best performance, and the robot could crawl up a 37° slope. (2) When the deflection angle of the driving wheel was set to 30°, the robot could smoothly pass a bend with a radius of curvature of 500 mm. Thus, the robot performance met the design requirements.

This article proposes a model for Chinese text classification based on a feature-enhanced nonequilibrium bidirectional long short-term memory (Bi-LSTM) network that analyzes Chinese text information in depth and improves the accuracy of text classification. First, the bidirectional encoder representations from transformers model was used to vectorize the original Chinese corpus and extract preliminary semantic features. Then, a nonequilibrium Bi-LSTM network was applied to increase the weight of text information containing important semantics and further improve the effects of the key features in Chinese text classification. Simultaneously, a hierarchical attention mechanism was used to widen the gap between the important and unimportant data. Finally, the softmax function was used for classification. By comparing the classification performance of the proposed scheme with those of various other models, it was observed that the model substantially improved the precision of Chinese text classification and had a strong ability to recognize Chinese text features. The model achieved 97% precision on the experimental dataset.

Inherited antithrombin (AT) deficiency is an autosomal dominant disorder associated with SERPINC1 mutations. In this study, we generated a human induced pluripotent stem cell (iPSC) line ZZUNEUi014-A from peripheral blood mononuclear cells of a female AT deficiency patient with the p. W27X (c. 80G > A) mutation in SERPINC1. This cell line expressed pluripotency markers, showed normal female karyotype and could differentiate into all three germ layers in vitro.

Conducting polymers have received tremendous attentions owing to their great potentials to harvest both luminous and thermal energies. Here, we reported a flexible transparent electrode of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) with highly electrical conductivity and raised Seebeck coefficient via thionyl chloride treatments. The comprehensive studies of optical, electrical, morphological, structural, and thermoelectrical properties, work function, and stability of the PEDOT:PSS transparent electrodes were systematically evaluated and described. On the basis of the PEDOT:PSS transparent electrodes, the resultant flexible organic solar cells yielded a high power conversion efficiency of 15.12%; meanwhile, the flexible thermoelectricities exhibited the raised power factor of 115.9 μW m−1 K−2, which outperformed the four kinds of rigid thermoelectricities with conventional acid and base treatments.

There is ample evidence that the success or failure of language learning is influenced by psychological processes in learners' minds. This review attempted to review the related studies on the relationship between English as a Foreign Language (EFL) learners' emotional intelligence, communication apprehension, and self-efficacy. Few studies have been done on the correlation between self-efficacy and emotional intelligence. A positive significant correlation between emotional intelligence and self-efficacy has been confirmed in the literature. Studies have shown that interpersonal relationships, self-awareness, problem-solving skills, self-adequacy, self-confidence, self-actualization, and stress tolerance can act as mediator variables in the correlation between self-efficacy and emotional intelligence among EFL learners. Moreover, the related studies have shown that emotional intelligence is significantly correlated with communication apprehension. The investigations have accentuated the mediating role of learners' willingness to communicate and academic achievement in the correlation between emotional intelligence and communication apprehension. The correlation between communication apprehension and self-efficacy has been verified in the related literature. Finally, the pedagogical implications are expanded to foster language learning quality. This review also provides some suggestions for further research to elucidate our viewpoints over emotional variables and their interactions with each other.

The benefits of using wood in tall and commercial construction are undisputed, namely reducing the carbon footprint, shortening construction times, and enhancing seismic and building physics performance. The international market for wood as a structural material in tall and non-residential construction, however, is still relatively untapped. China is home to the world’s largest population and the largest construction sector worldwide, yet wood products are only used in a small fraction of buildings. The main reasons for this situation are the fire regulations and lack of guidelines for novel wood-based structural systems. This paper describes the design of a 10-storey timber-concrete business hotel which will be erected in the Guizhou province of China. The foundation design, gravity system design, lateral load resisting system design, seismic analysis and the fire resistance design were conducted, and the procedure provided appropriate information to the technological feasibility to promote the development of timber-based hybrid high-rise construction systems in China.

Material defects and external environmental factors increase the engineering safety risks of buried PE pipelines in service. This paper mainly reviews the failure mode and the prevention and control technology of buried PE pipelines in service, as well as comparative failure characteristics between the buried PE and steel pipelines. The main failure factors of buried PE pipelines can be divided into four levels: the first level is third-party damage; the second level includes three failure factors, i.e., surface subsidence, joint failure, and aging failure; the third level consists of pipe piercing, crack development, and pipeline defect; the fourth level is a corrosion failure. Besides, steel and PE pipelines have various physical and mechanical properties, which lead to a significant difference in the service performance and degradation mechanism in practice. For instance, corrosion and welded joint leakage are the two common problems in steel pipelines during the service period, while PE pipelines have excellent corrosion resistance. Additionally, in order to ensure and maintain the long-term operations of PE pipelines, it is of great significance to develop and promote nonexcavation technologies of construction, renewal, and repair for natural gas-buried PE pipelines. Furthermore, based on the above studies, some further research studies on buried PE pipelines in service are suggested and discussed, e.g., (a) the service performance and degradation mechanism of buried PE pipelines in complicated environmental conditions, (b) the interaction mechanism among the engineering structure, PE pipelines, and geological environment, as well as PE pipeline geological soils coupled in multiple physical fields, and (c) the combinations of the traditional engineering risk assessment method and the numerical analysis method considering the interaction between the PE pipeline and geological environment. The results could be helpful for a better understanding of the operation conditions of buried PE pipelines, and it is also hoped that this study could provide guidance for the safe operation, maintenance, and integrity management of buried PE pipelines.

Estimating the precise nutritional status of crop nitrogen (N) after flowering period is not only important to predict deficiency but the excess that could be revised by fertilization in future crops. Critical N dilution curves describing the critical N concentration ([N]c) in plant tissues during crop growth have been used to estimate the N status of whole plants in cotton. Little is known, however, about the critical N dilution curve for specific plant organs such as cotton fruits. The objective of this study was to verify the feasibility of fruits-based critical N dilution curve as a useful diagnostic tool for diagnosing the N status of cotton crops. A 3-year field experiment was conducted with seven N application rates (0–360 kg N ha–1) using the high-yielding cultivars Jimian 228 and Lumian 28, which differ in maturity. The relationship between fruits dry mass (DM) and N concentration ([N]) was analyzed, and a model of [N]c for cotton fruits was constructed and validated. The results showed that fruits [N]c decreased with increasing fruits DM. The critical N dilution curve based on cotton fruits was described by the equation [N]c = 2.49 × DM–0.12 (R2 = 0.649, P < 0.0001) across cultivar-years. The N nutrition index (NNI) of the fruits (NNIf) with the N dilution curve was significantly related to the NNI of shoot DM, relative yield (RY), and boll density at most sampling dates. For an NNIf of approximately 1, the RY was nearly 95%, while it decreased with a decreasing NNIf below 1. The petiole nitrate-N (NO3-N) concentration was also linearly related to the NNIf, suggesting that the NO3-N concentration in the petiole was a good predictor of the NNIf. Therefore, fruits-based critical N dilution curve and the derived NNIf values will serve as a useful diagnostic tool for diagnosing N status in cotton crops.

Abstract Background SMAD6 variants have been reported in patients with radioulnar synostosis (RUS). This study aimed to investigate the genotypes and phenotypes for a large cohort of patients with RUS having mutant SMAD6. Methods Genomic DNA samples were isolated from 251 RUS sporadic patients (with their parents) and 27 RUS pedigrees. Sanger sequencing was performed for the SMAD6 coding regions. For positive probands, co‐segregation and parental‐origin analysis of SMAD6 variants and phenotypic re‐evaluation were performed for their family members. Results We identified 50 RUS probands with SMAD6 variants (13 co‐segregated with RUS in pedigrees and 37 in RUS‐sporadic patients). Based on the new and previous data, we identified SMAD6 mutated in 16/38 RUS pedigrees and 61/393 RUS sporadic patients, respectively. Overall, 93 SMAD6 mutant patients with RUS were identified, among which 29 patients had unilateral RUS, where the left side was more involved than the right side (left:right = 20:9). Female protective effects and non‐full penetrance were observed, in which only 6.90% mothers (vs. ~50% fathers) of SMAD6 mutant RUS probands had RUS. Pleiotropy was observed as a re‐evaluation of SMAD6 mutant families identified: (a) three families had axial skeletal malformations; (b) two families had polydactyly; and (c) eight families had other known malformations. Conclusion SMAD6 was mutated in 42.11% RUS pedigrees and 15.52% RUS sporadic patients. The RUS patients with SMAD6 variants exhibit both non‐full‐penetrance, variable expressivity, pleiotropy, female protective effects, and the left side is more susceptible than the right side.

To obtain the contact parameters of the moist bulk of shotcrete accurately and quickly, this study calibrated the contact parameters of the moist bulk of shotcrete by physical stacking test and simulation method. Based on the Hertz–Mindlin with JKR (Johnon–Kendall–Roberts) model, the discrete element simulation is carried out. Using P-BD to screen seven initial parameters, it is found that JKR surface energy, rolling friction coefficient between particles and restitution coefficient of particle impact have significant effects on the angle of repose of the moist bulk of shotcrete. According to B-BD, the second-order regression model of angle of repose and significance parameters was established. Three significant parameters were obtained: JKR surface energy 0.418 J/m2, rolling friction coefficient 0.06 and static friction coefficient 1. The angle of repose obtained by simulation is compared with the physical test value, and the relative error is 1.88%. The results show that the calibration method proposed in this study can accurately simulate the physical stacking test, and can provide a reference for the calibration of contact parameters of the moist bulk of shotcrete.

The new generation of spaceborne laser altimeter, the Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2), which can simultaneously generate laser reflections on the water surface and underwater, is a potential data source for exploring water depth in nearshore environments. To achieve this scientific goal, accurate bathymetric photon extraction is needed. This study proposed a pre-pruning quadtree isolation (PQI) method with changing threshold. Firstly, the pre-pruning step is introduced. Photons are transformed into different levels in the isolated quadtree structure according to spatial density. Then, the frequency histogram of photon elevation and isolated level (IL) is generated, the IL thresholds in different depth ranges are calculated by the Otsu method, and the bathymetric photons are extracted. The results in the Culebra archive show that this method achieved a 92.71% F1 score. Noise rate and water depth are the main factors affecting the extraction of sounding photons. When the photon density gradually increases from 2–4 pts/m to 6–8 pts/m, the F1 score of PQI decreases by no more than two percent. In different depth ranges, the extraction results of PQI are also better than those of comparison methods. Therefore, PQI can provide reliable theoretical support for nearshore areas lacking water depth data.

Jellyfish is a valuable biological resource in marine ecosystems, and blooms been observed in numerous coastal regions. However, their utility is limited by their high water content. Recent research has focused on extracting antioxidants from marine sources. In this study, we obtained jellyfish peptides (JPHT-2) through enzymatic hydrolysis of lyophilized jellyfish powder under optimal conditions and measured their antioxidant activity. Our findings indicate that JPHT-2 possesses significant radical-scavenging activity and reducing power. At a concentration of 0.74 mg/mL, JPHT-2 exhibited a remarkable ability to scavenge hydroxyl radicals, with a rate of up to 50%. The EC50 values for scavenging superoxide anion and DPPH radical were 1.55 mg/mL and 1.99 mg/mL, respectively. At the cellular level, JPHT-2 was able to protect HaCaT cells from H2O2-induced oxidative damage by increasing the level of superoxide dismutase (SOD) in cells. In conclusion, jellyfish peptides with low molecular weight can be easily obtained through hydrolysis with three enzymes and exhibit excellent antioxidant activity and safety. Jellyfish can serve as a promising source of antioxidants.

Chiral amines are essential components for many pharmaceuticals and agrochemicals. However, the difficulty in obtaining enantiomerically pure amines limits their application. In this study, hollow amorphous ZIF-90 (HamZIF-90) materials were prepared by template engraving, and chemical–enzyme coupling catalysts (HamZIF-90@Pd@CALB) were constructed for the chiral resolution of 1-phenylethylamine. Different from conventional materials, HamZIF-90 had tunable hollow structures by altering its central node zinc ion concentrations, and the embedded hydrogel template gave it more pore structures, which facilitated the loading of enzyme molecules and Pd nanoparticles (NPs). The establishment of the coupling catalysts shortened the mass transfer distance of the reactant molecules between the metal nanoparticles and the enzyme catalyst in the dynamic kinetic resolution (DKR) reaction, resulting in 98% conversion of 1-phenylethylamine and 93% selectivity of Sel.R-amide. The proposal of this idea provided a good idea for future tailor-made MOFs loaded with chemical and enzyme coupled catalyst.

Malus hupehensis (MH), as a natural resource, contains various active ingredients such as polyphenols, polysaccharides, proteins, amino acids, volatile substances, and other components. Increasingly, studies have indicated that MH showed a variety of biological activities, including antioxidant, hypoglycemic, hypolipidemic, anti-cancer, anti-inflammatory activities, and other activities. Hence, MH has attracted wide interest because of its high medical and nutritional value. It is necessary to review the active components and biological activities of MH. This paper systematically reviewed the chemical substances, biological activities, and potential problems of MH to further promote the related research of MH and provide an important reference for its application and development in medicine and food.

Scyphozoan Nemopilema nomurai envenomation is an unresolved threat to human health in Asian waters. Nemopilema nomurai venom metalloproteinases show important toxicities in skin damage and inflammation, but there is still no purified protein for further studies. In this study, high proteinase activity fractions in tentacle autolysis were isolated by ammonium sulfate precipitation, DEAE Sepharose Fast Flow, and Superdex 75 chromatography successively. Purification was guided by azocasein hydrolysis activity and SDS-PAGE. The final products were analyzed by LC-MS/MS. Four elution peaks purified by Superdex 75 chromatography had multiple protein bands but did not show proteinase activity. These fractions would recover proteinase activity after mixing again. Regulation mechanisms were speculated as binding metalloproteinase regulator or disaggregating metalloproteinase inhibitor by LC-MS/MS analysis. For the first time, a synergistic effect in N. nomurai proteinase activity was found in the purification process.

The maize (Zea mays L.) ZmCNR13 gene, encoding a protein of fw2.2-like (FWL) family, has been demonstrated to be involved in cell division, expansion, and differentiation. In the present study, the genomic sequences of the ZmCNR13 locus were re-sequenced in 224 inbred lines, 56 landraces and 30 teosintes, and the nucleotide polymorphism and selection signature were estimated. A total of 501 variants, including 415 SNPs and 86 Indels, were detected. Among them, 51 SNPs and 4 Indels were located in the coding regions. Although neutrality tests revealed that this locus had escaped from artificial selection during the process of maize domestication, the population of inbred lines possesses lower nucleotide diversity and decay of linkage disequilibrium. To estimate the association between sequence variants of ZmCNR13 and maize ear characteristics, a total of ten ear-related traits were obtained from the selected inbred lines. Four variants were found to be significantly associated with six ear-related traits. Among them, SNP2305, a non-synonymous mutation in exon 2, was found to be associated with ear weight, ear grain weight, ear diameter and ear row number, and explained 4.59, 4.61, 4.31, and 8.42% of the phenotypic variations, respectively. These results revealed that natural variations of ZmCNR13 might be involved in ear development and can be used in genetic improvement of maize ear-related traits.

Macrophages and fibroblasts are two types of important cells in wound healing. The development of novel platforms for studying the interrelationship between these two cells is crucial for the exploration of wound-healing mechanisms and drug development. In this study, a microfluidic chip composed of two layers was designed for the co-culturing of these two cells. An air valve was employed to isolate fibroblasts to simulate the wound-healing microenvironment. The confluence rate of fibroblasts in the co-culture system with different macrophages was explored to reflect the role of different macrophages in wound healing. It was demonstrated that M2-type macrophages could promote the activation and migration of fibroblasts and it can be inferred that they could promote the wound-healing process. The proposed microfluidic co-culture system was designed for non-contact cell–cell interactions, which has potential significance for the study of cell–cell interactions in biological processes such as wound healing, tumor microenvironment, and embryonic development.

Building energy simulation plays a significant role in buildings, with applications such as building performance evaluation, retrofit decisions and the optimization of building operations. However, the wide range of model inputs has limited much research into empirically customized case studies due to the insufficient availability of data inputs or the lack of systematic feature selection of key inputs. To address this gap, this study proposes the concept of minimum variable sets (MVSs) for building energy-prediction models to improve the general applicability of building energy prediction using forward simulation. An MVS, in this paper, refers to a variable set that contains the most indispensable energy-related variables/features for annual building energy prediction. This study developed MVSs for office buildings by applying feature engineering algorithms to a Building Performance Database (BPD), which was established by integrating the design of experiments (DoE) method with high-dimensional data-space metrics, as well as parallel simulation. Supervised feature dimension reduction methods and multiple statistical criteria were adopted to choose different numbers of indispensable variables from the primary 16 building variables. The hierarchical MVSs that consist of the selected variables are characterized by the most influential features for building energy prediction, with certain requirements for prediction accuracy. To further improve the feasibility of MVSs, this study utilized two separate office buildings located in Shanghai and California as validation cases and provided comparable prediction accuracies across different sizes of MVS. The results showed that the MVS that has 12 variables has higher prediction accuracy than that which has 9 variables, followed by that which has 7 variables. Finally, the quantitatively hierarchical correlations between different sizes of MVS with different prediction accuracies for annual building energy could provide potential support for reasonable decision-making regarding building energy model variables, especially when comprehensive consideration is needed of the limited cost and data availability, and the acceptable accuracy of building energy.

The influence of biotech crops on microbial communities in rhizosphere soil is an important issue in biosafety assessments. The transgenic maize HGK60 harboring the Bt cry1Ah gene enhanced the resistance to lepidopteran pests, while the ecological risk of HGK60 maize on rhizosphere microorganisms is unclear. In this study, we comprehensively analyzed the diversity and composition of bacterial and fungal communities in the rhizosphere soil around Bt maize HGK60 and the near-isogenic non-Bt maize ZD958 at four growth stages via a high-throughput sequencing technique. The results showed that HGK60 maize unleashed temporary effects on the bacterial and fungal diversity and richness during the study plant’s development, which would be restored after one cycle of plant cultivation due to the application of the same agricultural management. The differences of bacterial and fungal communities were marked by seasonality, while the different growth stage was the important factor as opposed to the cultivar contributing to the shifts in the bacterial and fungal communities’ structure. This study will provide useful information regarding the impact of Bt transgenic maize on the soil microbiome and a theoretical basis for the development of a safety assessment approach for Bt maize in China.

In this paper, we focus on a developable surface tangent to a timelike surface along a curve in Minkowski 3-space, which is called the osculating developable surface of the timelike surface along the curve. The ruling of the osculating developable surface is parallel to the osculating Darboux vector field. The main goal of this paper is to classify the singularities of the osculating developable surface. To this end, two new invariants of curves are defined to characterize these singularities. Meanwhile, we also research the singular properties of osculating developable surfaces near their lightlike points. Moreover, we give a relation between osculating Darboux vector fields and normal vector fields of timelike surfaces along curves from the viewpoint of Legendrian dualities. Finally, some examples with symmetrical structures are presented to illustrate the main results.

It is shown that the inclusion of hadronic interactions, and in particular nuclear potentials, in simulations of heavy ion collisions at the SPS energy range can lead to obvious correlations of protons. These correlations contribute significantly to an intermittency analysis as performed at the NA61 experiment. The beam energy and system size dependence is studied by comparing the resulting intermittency index for heavy ion collisions of different nuclei at beam energies of 40A, 80A and 150A GeV. The resulting intermittency index from our simulations is similar to the reported values of the NA61 collaboration, if nuclear interactions are included. The observed apparent intermittency signal is the result of the correlated proton pairs with small relative transverse momentum Δpt, which would be enhanced by hadronic potentials, and this correlation between the protons is slightly influenced by the coalescence parameters and the relative invariant four-momentum qinv cut.

Abstract Background Long-term rotary tillage has led to the deterioration of cotton production in northern China. This deterioration is due to the disturbance of topsoil, a dense plough pan at the 20–50 cm depth, and the decreased water storage capacity. A 2-yr field experiment was performed from 2014 to 2015 to explore a feasible soil tillage approach to halting the deterioration. The experiment consisted of four treatments: replacing the topsoil from the 0–15 cm layer with the subsoil from the 15–30 cm layer (T1); replacing the topsoil from the 0–20 cm layer with the subsoil from the 20–40 cm layer and subsoiling at the 40–55 cm layer (T2); replacing the topsoil from the 0–20 cm layer with the subsoil from the 20–40 cm layer and subsoiling at the 40–70 cm layer (T3); and conventional surface rotary tillage within 15 cm as the control (CK). Results The results indicated that the soil bulk densities at the 20–40 cm layer in T2 were 0.13 g·cm− 3 and 0.15 g·cm− 3 lower than those obtained from CK in 2014 and 2015, respectively. The total nitrogen (N) and the available phosphorus (P) and potassium (K) contents from the 20–40 cm layer in T2 and T3 were significantly higher than those in CK and T1. The amount of soil water stored in the 0–40 cm layer of T2 at the squaring stage of cotton was 15.3 mm and 13.4 mm greater than that in CK in 2014 and 2015, respectively, when the weather was dry. Compared with CK, T2 increased cotton lint yield by 6.1 and 10.2 percentage points in 2014 and 2015, respectively, which was due to the improved roots within the 20–60 cm layer, the greater number of bolls per plant and the higher boll weight in the T2 treatment. Conclusions The results suggested that soil replacement plus subsoiling would be a good alternative to current practices in order to break through the bottleneck constraining cotton production in northern China. Replacing the topsoil in the 0–20 cm layer with the soil from the 20–40 cm layer plus subsoiling at the 40–55 cm layer would be the most effective method.

We report a simple one-step hydrothermal strategy for the fabrication of a C-MoS2/rGO composite with both large surface area and high porosity for the use as advanced electrode material in lithium–sulfur batteries. Double modified defect-rich MoS2 nanosheets are successfully prepared by introducing reduced graphene oxide (rGO) and amorphous carbon. The conductibility of the cathodes can be improved through the combination of amorphous carbon and rGO, which could also limit the dissolution of polysulfides. After annealing at different temperatures, it is found that the C-MoS2/rGO-6-S composite annealed at 600 °C yields a noticeably enhanced performance of lithium–sulfur batteries, with a high specific capacity of 572 mAh·g−1 at 0.2C after 550 cycles, and 551 mAh·g−1 even at 2C, much better than that of MoS2-S nanosheets (249 mAh·g−1 and 149 mAh·g−1) and C-MoS2/rGO-S composites (334 mAh·g−1 and 382 mAh·g−1). Our intended electrode design protocol and annealing process may pave the way for the construction of other high-performance metal disulfide electrodes for electrochemical energy storage.

Pot experiments were conducted in 2017 with two cotton cultivars (CCRI 79 and LMY 28) and three phosphorus (P) levels: 3, 8 and 12 mg P2O5/kg as P0, P1 and P2, respectively. In this study, the soil water-soluble organic carbon content increased as the soil available P (AP) increased, while there were no significant variations for soil total organic matter content among the three AP levels. The activities of invertase, cellulase and urease in cotton soil decreased significantly in the P0. There were positive correlations between invertase and cellulose activities with soil organic carbon and inorganic-nitrogen (N); these correlated negatively with soil C/N ratio and AP level. In addition, high soil AP can raise soil AP and enhance alkaline phosphatase activity, which had a significant negative relationship with the soil C/P ratio. Urease activity had a significant positive relationship with soil NH4+-N, C/P and N/P, as well as a negative correlation with soil C/N. Moreover, soil NH4+-N and NO3--N in the P1 and P2 were lower than in the P0, which might be an effect of high AP on soil N availability.

Abstract Background LEAFY COTYLEDON 2 (LEC2) acts throughout embryo morphogenesis and maturation phase to maintain embryogenic identity. Our previous study stated that Arabidopsis thaliana LEC2 (AtLEC2) driven by glucocorticoid receptor-dexamethasone (GR-DEX) inducible system (AtLEC2-GR) triggers embryogenic callus formation in tobacco (Nicotiana tabacum). Results In this study, the adenosine phosphate isopentenyltransferase genes AtIPT3, AtIPT7 and the tRNA isopentenyltransferase gene AtIPT9 were overexpressed in the AtLEC2-GR transgenic background. In the AtIPT7-OE AtLEC2-GR and AtIPT9-OE AtLEC2-GR seedlings, high-quality embryogenic callus was obtained under the DEX condition, and the shoot regeneration efficiency was 2 to 3.5 folds higher than AtLEC2-GR alone on hormone free medium without DEX. Transcriptome analyses showed that up-regulated BBM, L1L, ABI3, and FUS3 might function during embryogenic callus formation. However, at the shoot regeneration stage, BBM, L1L, ABI3, and FUS3 were down-regulated and Type-B ARRs were up-regulated, which might contribute to the increased shoot regeneration rate. Conclusions A novel system for inducing shoot regeneration in tobacco has been developed using the GR-DEX system. Induced expression of AtLEC2 triggers embryogenic callus formation and overexpression of AtIPT7 or AtIPT9 improves shoot regeneration without exogenous cytokinin.

Abstract Background Overfeeding reduces laying performance in broiler breeder hens, which is associated with obesity, hepatic steatosis and systemic inflammation. To unravel the underlying mechanisms governing the effect of feeding regimes on energy metabolism and egg production, a transcriptomics approach was carried out for screening differentially expressed genes (DEGs) in ovary, liver and adipose tissues of broiler chickens under ad libitum and restricted feeding. Results It showed that 289, 388 and 204 DEGs were identified in the adipose, liver and ovary, respectively. These DEGs were significantly enriched in phagosome pathway, lipid transport, activity and nutrient reservoir activity in ovary; steroid hormone biosynthesis and metabolism of xenobiotics by cytochrome P450 pathways in adipose tissue; and the metabolic pathways, peroxisome proliferator-activated receptor (PPAR) and Jak-STAT signaling pathway in liver. Estrogen receptor 1, identified as one of important hubs by constructing PPI network, was up-regulated in ad libitum group, which would make more apolipoproteins be transferred to ovary. Conclusions High expression of VTGs, APOB, CYBB and CTSS in ovary would induce excess lipid deposit, oxidative stress and potential damage to ovulation. Our results contribute to understanding effects of feeding regimes on metabolic regulation during egg production of broiler breeder hens and also provide new evidence of metabolic regulation from integrated multi-tissue processes.

Abstract Background Brain image segmentation is the basis and key to brain disease diagnosis, treatment planning and tissue 3D reconstruction. The accuracy of segmentation directly affects the therapeutic effect. Manual segmentation of these images is time-consuming and subjective. Therefore, it is important to research semi-automatic and automatic image segmentation methods. In this paper, we propose a semi-automatic image segmentation method combined with a multi-atlas registration method and an active contour model (ACM). Method We propose a multi-atlas active contour segmentation method using a template optimization algorithm. First, a multi-atlas registration method is used to obtain the prior shape information of the target tissue, and then a label fusion algorithm is used to generate the initial template. Second, a template optimization algorithm is used to reduce the multi-atlas registration errors and generate the initial active contour (IAC). Finally, a ACM is used to segment the target tissue. Results The proposed method was applied to the challenging publicly available MR datasets IBSR and MRBrainS13. In the MRBrainS13 datasets, we obtained an average thalamus Dice similarity coefficient of 0.927 ± 0.014 and an average Hausdorff distance (HD) of 2.92 ± 0.53. In the IBSR datasets, we obtained a white matter (WM) average Dice similarity coefficient of 0.827 ± 0.04 and a gray gray matter (GM) average Dice similarity coefficient of 0.853 ± 0.03. Conclusion In this paper, we propose a semi-automatic brain image segmentation method. The main contributions of this paper are as follows: 1) Our method uses a multi-atlas registration method based on affine transformation, which effectively reduces the multi-atlas registration time compared to the complex nonlinear registration method. The average registration time of each target image in the IBSR datasets is 255 s, and the average registration time of each target image in the MRBrainS13 datasets is 409 s. 2) We used a template optimization algorithm to improve registration error and generate a continuous IAC. 3) Finally, we used a ACM to segment the target tissue and obtain a smooth continuous target contour.

Camera shakes cause video motion blur. Video deblurring has been studied for years, and however, there are still unresolved problems, such as video frame alignment, frame selection, and frame ambiguity evaluation. We propose a video deblurring algorithm based on the motion vector and an encoder-decoder network. Our algorithm consists of four steps: first, the blurry image blocks in a video frame are located using a blurred image quality evaluation algorithm based on a response function of singular values. Second, the corresponding candidates of the blurry image block in the consecutive frames are searched using the motion vector, and the optimal candidate blocks are obtained using an objective function. Third, the blurry image block and the optimal candidate blocks are served as samples, which are inputted to an encoder-decoder network, so that the blurry image block is repaired. Finally, all blurry image blocks are replaced with the repaired ones, the boundary artifacts are eliminated, and the entire video frame is repaired. The experiments show that our algorithm yields sharper repair results, and the overall performance of our algorithm is better than other related algorithms.

Autonomous vehicles (AVs) are supposed to make appropriate strategies to ensure driving safety and improve traffic efficiency. However, not all collisions will be avoidable. In a typical dilemma scenario of this paper, we have to make hard decisions from two evils, sparing a child with red-light running behavior or crashing into a well-equipped motorcycle driver without violation of the traffic law. Combined with the existing traffic laws and the accident liability judgment cases in China, 12 typical dilemma scenarios are established. In order to acquire data to analyze the driving decision-making factors involving ethics and legal under the moral dilemma of AVs, we conduct a series of experiments in virtual reality environments. Furthermore, key factors are extracted to characterize the driving decisions under different scenarios and quantified by the gray relation entropy analysis method. Particularly, the ethical factor is represented by the quantity and type of collision targets, the legal factor is qualified by rights of way. The results showed that priority levels of the influencing factors in each moral dilemma were considerably different. Nevertheless, when the quantity of collision targets on two sides is equal, more participants prefer to protect the ones that comply with traffic rules. The research results can provide the basis for designing moral algorithms for the AVs.

In this study, the therapeutic effects of buckwheat hull flavonoids (BHFs) on type 2 diabetes db/db mice were investigated. After administration by BHFs nine weeks, body weight, visceral index, biochemical indicators in serum and in liver were detected. The liver pathological changes were observed under microscopic observations. Real-time quantitative PCR was used to detect IRS-1, PI3kα, AKT2, SREBP-1c, FAS, ACC1 mRNA expression in liver. The results showed that insulin resistance significantly reduced after the BHFs treatment. BHFs could reduce the TG, TC, vLDL-c, FFA levels in serum and TG, TC levels in liver and potentiate insulin resistance-related PI3k/AKT2 signal pathway and down-regulated SREBP-1c, FAS, ACC1 mRNA in the liver tissue of db/db mice. Moreover, BHFs could significantly alleviate the structure disorder of liver. The protective effect of BHFs on T2DM may be mediated by facilitating PI3k/AKT signal pathway and down-regulating SREBP-1c, FAS and ACC1 mRNA expression to reduce lipid synthesis.

Context: Compounds to treat hypothyroidism in the absence of cardiac side effects are urgently required. In this regard, γ-aminobutyric acid (GABA) has gained interest due to its anti-anxiolytic, antihypertensive and antioxidant properties, and reported benefits to the thyroid system. Objective: We investigated the ability of GABA to ameliorate fluoride-induced thyroid injury in mice, and investigated the mechanism(s) associated with GABA-induced protection. Materials and methods: Adult male Kumning mice (N = 90) were exposed to NaF (50 mg/kg) for 30 days as a model of hypothyroidism. To evaluate the effects of GABA administration, fluoride-exposed mice received either thyroid tablets, or low (25 mg/kg), medium (50 mg/kg) or high (75 mg/kg) concentrations of pure GABA orally for 14 days groups (N = 10 each). The effects of low (50 mg/kg); medium (75 mg/kg) and high (100 mg/kg) concentrations of laboratory-separated GABA were assessed for comparison. Effects on thyroid hormone production, oxidative stress, thyroid function-associated genes, and side-effects during therapy were measured. Results: GABA supplementation in fluoride-exposed mice significantly increased the expression of thyroid TG, TPO, and NIS (P

Short-chain fructo-oligosaccharides (scFOS) exert beneficial effects on growth performance and immune function of piglets. However, the effects of scFOS on intestinal integrity of piglets remain to be understood. This study was conducted to investigate the protective effects of scFOS on the intestinal barrier function of piglets. A total of 16 castrated male piglets weaned at 28 d were randomly allocated into 1 of 2 dietary treatments (n = 8): a control diet (CON) or a scFOS-supplemented diet (4 g/kg scFOS substituted the same amount of maize in CON). The experiment lasted 28 d. The average daily scFOS intake of treated group was 1.94 g. Results showed that scFOS consumption increased average daily gain and decreased feed to gain ratio and diarrhoea index (p

Endotracheal hamartomas are rarely encountered in children. The symptoms of endotracheal hamartoma may include cough, dyspnea, hemoptysis, chest pain, purulent sputum, and fever. The non-specific symptoms often result in a delayed diagnosis. Among the various treatments of this rare disease, surgical resection seems to be the most widely used, while endoscopic treatment is rarely described. Herein, we describe the case of a 9-year-old boy with an endotracheal hamartoma that was successfully excised by electrosurgical snaring via fiberoptic bronchoscopy (FB). The resection of select benign endotracheal tumors in children can be conducted using electrocautery, which can be regarded as an alternative therapy to bronchotomy.

Human and nonhuman primates are good at identifying an object based on its motion, a task that is believed to be carried out by the ventral visual pathway. However, the neural mechanisms underlying such ability remains unclear. We trained macaque monkeys to do orientation discrimination for motion boundaries (MBs) and recorded neuronal response in area V2 with microelectrode arrays. We found 10.9% of V2 neurons exhibited robust orientation selectivity to MBs, and their responses correlated with monkeys’ orientation-discrimination performances. Furthermore, the responses of V2 direction-selective neurons recorded at the same time showed correlated activity with MB neurons for particular MB stimuli, suggesting that these motion-sensitive neurons made specific functional contributions to MB discrimination tasks. Our findings support the view that V2 plays a critical role in MB analysis and may achieve this through a neural circuit within area V2.

EPSP synthase is the target enzyme of glyphosate herbicides. Due to the extensive use of glyphosate, it is very important to obtain EPSPS genes with high glyphosate resistance for the development of transgenic crops. GR79-EPSPS is a class I EPSP synthase with certain glyphosate resistance isolated from glyphosate-contaminated soil. After more than 1000 generations, a Y40I substitution was identified, and the enzyme had a nearly 1.8-fold decrease in Km [PEP] and a 1.7-fold increase in Ki[glyphosate] compared to the wild-type enzyme. Enzyme dynamics and molecular dynamics analysis showed that the substitution was near the hinge region of EPSPS, and the affinity of glyphosate binding to amino acid residues of the active site decreased due to Y40I substitution, resulting in an increase in glyphosate resistance. These results provide more evidence for the combination of directed evolution and rational design of protein engineering.

In this article, a topology based on the single-phase full-bridge is proposed to decouple control of phase current in current source grid-connected inverters. The DC side of this current source inverter topology can operate with a common DC bus or independently, and the AC side can be independently integrated into the three-phase grid or operate in parallel. This topology needs only a simple control logic and phase information to achieve 3-phase current decoupling control, which can accommodate a wide range of voltage fluctuations. Then, dual-carrier driving and hybrid damping correction strategies are designed to achieve flexible combinatorial operation and eliminate the common-mode voltage. Meanwhile, the method is simple and easy to implement in practice. The effectiveness of the proposed algorithm is validated with experiments.

Complete traffic sensor data is a significant prerequisite for analyzing the changing rules of traffic flow and formulating traffic control strategies. Nevertheless, the missing traffic data are common in practice. In this study, an improved Fuzzy C-Means algorithm is proposed to repair missing traffic data, and three different repair modes are established according to the correlation of time, space, and attribute value of traffic flow. First, a Twice Grid Optimization (TGO) algorithm is proposed to provide a reliable initial clustering center for the FCM algorithm. Then the Sparrow Search Algorithm (SSA) is used to optimize the fuzzy weighting index m and classification number k of the FCM algorithm. Finally, an experimental test of the traffic sensor data in Shunyi District, Beijing, is employed to verify the effectiveness of the TGO-SSA-FCM. Experimental results showed that the improved algorithm had a better performance than some traditional algorithms, and different data repair modes should be selected under different miss rate conditions.

Soil available phosphorus (AP) deficiency and shortage of phosphate rocks limit cotton production in China. Therefore, pool-culture experiments were conducted in 2019 and 2020 using two cotton cultivars (CCRI-79, low-P tolerant; SCRC-28, low-P sensitive) under three soil AP levels (P0: 3 ± 0.5, P1: 6 ± 0.5, and P2 (control): 15 ± 0.5 mg kg−1) to ascertain the effect of soil AP on boll biomass and lint yield. P0 and P1 decreased the P concentration and net photosynthetic rate (Pn) of subtending leaves, thus, reducing boll biomass and lint yield. Additionally, soil AP deficiency decreased boll wall:boll, lint:boll, and lint:seed, and increased seed:boll ratio. Upper fruiting branch positions (FB9–12) had higher lint:seed ratio and proportion of the total lint yield under low soil AP. Moreover, soil AP deficiency also reduced the sucrose transformation rate (Tr) and activities of sucrose-metabolizing enzymes, such as ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco), sucrose phosphate synthase (SPS), and sucrose synthase (SuSy), while increased carbohydrate levels (soluble sugar, sucrose, and starch) and the activity of cytosolic fructose-1,6-bisphosphatase (cy-FBPase) in the subtending leaves. The sucrose and starch contents, cy-FBPase, and SPS activities of SCRC-28 were more sensitive to low soil AP than CCRI-79. Higher Tr and activities of initial Rubisco and SuSy in the subtending leaves improved boll biomass and lint yield.

Brain-computer interface (BCI) for robotic arm control has been studied to improve the life quality of people with severe motor disabilities. There are still challenges for robotic arm control in accomplishing a complex task with a series of actions. An efficient switch and a timely cancel command are helpful in the application of robotic arm. Based on the above, we proposed an asynchronous hybrid BCI in this study. The basic control of a robotic arm with six degrees of freedom was a steady-state visual evoked potential (SSVEP) based BCI with fifteen target classes. We designed an EOG-based switch which used a triple blink to either activate or deactivate the flash of SSVEP-based BCI. Stopping flash in the idle state can help to reduce visual fatigue and false activation rate (FAR). Additionally, users were allowed to cancel the current command simply by a wink in the feedback phase to avoid executing the incorrect command. Fifteen subjects participated and completed the experiments. The cue-based experiment obtained an average accuracy of 92.09%, and the information transfer rates (ITR) resulted in 35.98 bits/min. The mean FAR of the switch was 0.01/min. Furthermore, all subjects succeeded in asynchronously operating the robotic arm to grasp, lift, and move a target object from the initial position to a specific location. The results indicated the feasibility of the combination of EOG and SSVEP signals and the flexibility of EOG signal in BCI to complete a complicated task of robotic arm control.

The physiological function of bamboo shoot sheaths is still unclear. In the present study, we investigated the anatomical and physiological influences of bamboo shoot sheaths on internode elongation by longitudinally striping parts of sheaths. The internodes would bend toward the bare sides during night. The results showed that amounts of water leaked at the cut of shoot sheaths during night, which impeded the increase of water, water pressure and assimilate transport rates, and decreased starch and soluble sugar catabolism in the bare side of the internodes. A higher level of water pressure and sugar metabolism increased the vacuole expansion and promoted the cell expansion in the outer sides as compared to the bare sides. The bending growth of internodes was mainly due to the significant differences in cell expansion, which was led by the difference in water pressure and sugar hydrolysis levels between the inner and outer sides. Bamboo internode elongation mainly relied on the increase of water pressure and soluble sugar concentration. Shoot sheaths played an important role in the rapid growth of bamboo shoots as a controller in water and assimilate transportation. This study gave a new insight into understanding the rapid growth mechanism of bamboo plants.

The association between the polymorphism of transforming growth factor (TGF)-β1 and risk of radiation pneumonitis has been extensively investigated; however, conclusive results were unavailable. Eligible studies were identified from the database of Medline, Web of Science, EMBASE, and CNKI (China Knowledge Resource Integrated Database) up to September 2019. The odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the strength of the relationship. The results showed that there were associations between TGF 869 T/C (rs1982073) and risks of radiation pneumonitis. Subgroup analyses showed that TGF 869 T/C was associated with risk of radiation pneumonitis in Caucasians (OR [95% CI]: 0.45 [0.31 to 0.67] for C carriers vs. TT). In addition, subgroup analyses also suggested that the C allele was associated with decreased risks of radiation pneumonitis among hospital-based case–control studies (0.56 [0.39 to 0.82] for C carriers vs. TT). Meanwhile, C allele was also suggested to be associated with decreased risk of radiation pneumonitis among PCC (0.60 [0.38 to 0.96] for C carriers vs. TT). Especially, C allele was also found to be associated with decreased risk of radiation pneumonitis from the participants with lung cancer (0.57 [0.37 to 0.90] for C carriers vs. TT). Our meta-analysis shows that T allele in TGF 869 T/C is significantly associated with the increased risk of radiation pneumonitis, especially for Caucasians, and for the participants with lung cancer.

Objective To analyze the clinical and laboratory features and determine the predictors of acute liver failure (ALF) among inpatients with anti-tuberculosis (TB) drug-induced liver injury (DILI). Method Patients diagnosed with anti-TB DILI from 2010 to 2016 at The First Affiliated Hospital of Zhejiang University were retrospectively included in this study. Demographic and clinical data were collected by reviewing electronic medical records. Results Among 155 inpatients with anti-TB DILI, 55 (35.48%) developed ALF, with an overall mortality of 9.68%. The median time to DILI onset was significantly longer in the ALF compared with the non-ALF group (51 versus 24 days). Eighty-three patients (53.55%) developed DILI (53.55%) within the first month of anti-TB treatment, and 60% of ALF cases occurred within 2 months. Multivariable models for ALF incorporating aspartate aminotransferase, total bilirubin, platelets, white blood cell count, and pre-existing hepatitis yielded a concordance (C-statistic) of 98.93%. Conclusions The results of this study suggest that approximately half of all cases of DILI occur within the first month, while 60% of ALF cases occur within 2 months. Elevated total bilirubin, aspartate aminotransferase, white blood cell count, pre-existing hepatitis, and low platelet count are independent risk factors for the development of anti-TB drug-induced ALF.

Ubiquitin-specific protease 2 (USP2) is an important member of the deubiquitination system. GEO dataset revealed that USP2 was downregulated in the hearts under pressure overload. However, the cardiomyocyte-specific function of USP2 in the setting of pressure overload is unknown. In the current study, a mouse model of pressure overload was induced by transverse aortic constriction (TAC, 2 weeks). Overexpression of USP2 in the heart was conducted by AAV9 infection. Changes in heart histology were detected by Masson’s trichrome staining and hematoxylin-eosin staining (H&E). Echocardiography was used to assess cardiac function. The size of cardiomyocytes was examined by wheat germ agglutinin (WGA) staining. Cardiac oxidative stress was detected by dihydroethidine staining. Our results showed that USP2 was downregulated in the cardiomyocytes following 2 weeks of TAC. Overexpression of cardiac USP2 preserved ventricular function following 2 weeks of TAC. Overexpression of cardiac USP2 inhibited TAC-induced cardiac remodeling, by suppressing cardiac hypertrophy, inhibiting inflammatory responses and fibrosis, and attenuating oxidative stress. Our findings reveal a previously unrecognized role of USP2 in regulating pressure overload-induced cardiac remodeling.

The activity of genome-specific repetitive sequences is the main cause of genome variation between Gossypium A and D genomes. Through comparative analysis of the two genomes, we retrieved a repetitive element termed ICRd motif, which appears frequently in the diploid Gossypium raimondii (D5) genome but rarely in the diploid Gossypium arboreum (A2) genome. We further explored the existence of the ICRd motif in chromosomes of G. raimondii, G. arboreum, and two tetraploid (AADD) cotton species, Gossypium hirsutum and Gossypium barbadense, by fluorescence in situ hybridization (FISH), and observed that the ICRd motif exists in the D5 and D-subgenomes but not in the A2 and A-subgenomes. The ICRd motif comprises two components, a variable tandem repeat (TR) region and a conservative sequence (CS). The two constituents each have hundreds of repeats that evenly distribute across 13 chromosomes of the D5genome. The ICRd motif (and its repeats) was revealed as the common conservative region harbored by ancient Long Terminal Repeat Retrotransposons. Identification and investigation of the ICRd motif promotes the study of A and D genome differences, facilitates research on Gossypium genome evolution, and provides assistance to subgenome identification and genome assembling.

Airborne LiDAR bathymetry (ALB) has proven to be an effective technology for shallow water mapping. To collect data with a high point density, a lightweight dual-wavelength LiDAR system mounted on unmanned aerial vehicles (UAVs) was developed. This study presents and evaluates the system using the field data acquired from a flight test in Dazhou Island, China. In the precision and accuracy assessment, the local fitted planes extracted from the water surface points and the multibeam echosounder data are used as a reference for water surface and bottom measurements, respectively. For the bathymetric performance comparison, the study area is also measured with an ALB system installed on the manned aerial platform. The object detection capability of the system is examined with placed small cubes. Results show that the fitting precision of the water surface is 0.1227 m, and the absolute accuracy of the water bottom is 0.1268 m, both of which reach a decimeter level. Compared to the manned ALB system, the UAV-borne system provides higher resolution data with an average point density of 42 points/m2 and maximum detectable depth of 1.7–1.9 Secchi depths. In the point cloud of the water bottom, the existence of a 1-m target cube and the rough shape of a 2-m target cube are clearly observed at a depth of 12 m. The system shows great potential for flexible shallow water mapping and underwater object detection with promising results.

The remaining useful life (RUL) prediction for hydrogen fuel cells is an important part of its prognostics and health management (PHM). Artificial neural networks (ANNs) are proven to be very effective in RUL prediction, as they do not need to understand the failure mechanisms behind hydrogen fuel cells. A novel RUL prediction method for hydrogen fuel cells based on the gated recurrent unit ANN is proposed in this paper. Firstly, the data were preprocessed to remove outliers and noises. Secondly, the performance of different neural networks is compared, including the back propagation neural network (BPNN), the long short-term memory (LSTM) network and the gated recurrent unit (GRU) network. According to our proposed method based on GRU, the root mean square error was 0.0026, the mean absolute percentage error was 0.0038 and the coefficient of determination was 0.9891 for the data from the challenge datasets provided by FCLAB Research Federation, when the prediction starting point was 650 h. Compared with the other RUL prediction methods based on the BPNN and the LSTM, our prediction method is better in both prediction accuracy and convergence rate.

We study the notions of pedal curves, contrapedal curves and B-Gauss maps of non-lightlike regular curves in Minkowski 3-space. Then we establish the relationships among the evolutes, the pedal and contrapedal curves. Moreover, we also investigate the singularities of these objects. Finally, we show some examples to comprehend the characteristics of the pedal and contrapedal curves in Minkowski 3-space.