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The tensor train (TT) format enjoys appealing advantages in handling structural high-order tensors. The recent decade has witnessed the wide applications of TT-format tensors from diverse disciplines, among which tensor completion has drawn considerable attention. Numerous fast algorithms, including the Riemannian gradient descent (RGrad), have been proposed for the TT-format tensor completion. However, the theoretical guarantees of these algorithms are largely missing or sub-optimal, partly due to the complicated and recursive algebraic operations in TT-format decomposition. Moreover, existing results established for the tensors of other formats, for example, Tucker and CP, are inapplicable because the algorithms treating TT-format tensors are substantially different and more involved. In this paper, we provide, to our best knowledge, the first theoretical guarantees of the convergence of RGrad algorithm for TT-format tensor completion, under a nearly optimal sample size condition. The RGrad algorithm converges linearly with a constant contraction rate that is free of tensor condition number without the necessity of re-conditioning. We also propose a novel approach, referred to as the sequential second-order moment method, to attain a warm initialization under a similar sample size requirement. As a byproduct, our result even significantly refines the prior investigation of RGrad algorithm for matrix completion. Lastly, statistically (near) optimal rate is derived for RGrad algorithm if the observed entries consist of random sub-Gaussian noise. Numerical experiments confirm our theoretical discovery and showcase the computational speedup gained by the TT-format decomposition. [ABSTRACT FROM AUTHOR]

Objectives This paper was to elucidate the advantages of using an effective crystalline inhibitor, which was hydroxypropyl methylcellulose E5 (HPMC), in inhibiting crystallisation for curcumin amorphous solid dispersion (Cur ASDs) formulated by Eudragit E100 (E100). Methods Physical characterisation such as differential scanning calorimetry and powder X-ray diffraction revealed the solid state during the formation of dispersion and clarified the compatibility between Cur and excipient. Key findings The liquidity of excipient and the change of Tg in Cur ASDs demonstrated that the addition of HPMC can reduce molecule motion of the whole system, improve Tg of Cur ASDs and inhibit crystallisation of Cur ASDs. The water uptake experiment and molecular dynamic modelling further confirmed the effective solution and matrix crystallisation inhibition role of HPMC. Conclusions The elucidation of HPMC as auxiliary excipient on inhibiting crystallisation for Cur ASDs will bring huge value in designing Cur ASDs in the future. [ABSTRACT FROM AUTHOR]

A precise and convenient targeting architecture for accomplishing the rendezvous of a lunar lander with an orbiter in a near-circular lunar parking orbit is proposed in this paper. This procedure enables a systematic design and refinement of the number of thrust impulses, their application times, and the mission duration. The simplicity and accuracy of this targeting procedure makes it well suited for onboard use during real-time control and strategy reconstruction operations. A concise and revealing form of the linearized rendezvous equations is derived based on the Clohessy-Wiltshire model, as adopted to generate feasible initial solutions to satisfy the demands of rapid mission analysis and design. A three-step iterative procedure is adopted to determine the minimum-impulse control strategies for autonomous rendezvous, involving the progress of the solution from a linear model to a nonlinear, two-body model and finally to a high-fidelity model. The two-body model is introduced as an intermediary to enable a smooth transition from the linear to the high-fidelity lunar gravitational model. Numerical simulations are undertaken to verify the control strategies calculated and to illustrate the efficiency and convergence of the proposed iteration algorithm. [ABSTRACT FROM AUTHOR]

A precise and convenient procedure for designing the two-segment lunar free-return trajectory is presented in this paper. The trajectory characteristics are analyzed to support the lunar mission design associated with the higher inclination lunar approaches and safer returns from the moon. The concise procedure is established based on the matched conic model. An analytical algorithm is developed to compute the spacecraft state at the lunar sphere of influence to complete the conic matching. An iteration process is then adopted to generate favorable initial solutions that satisfy the constraints at injection, perilune, and Earth-entry interface. Orbital launch windows for departure from Earth, lunar encounter, and returns to Earth are established in the years 2024 and 2034. These years are chosen due to the moon's inclination reaching a maximum in 2024 and it reaching a minimum in 2034 during a Metonic cycle. This novel trajectory enables greater lunar surface coverage than standard free-return trajectories. The trajectory can be used to lower the fuel consumption for high-latitude lunar orbiting and landing. In case a mission should be aborted in the lunar approach stage, the spacecraft can safely return without additional maneuvering. The initial trajectory is modified in a high-fidelity gravitational model and the results indicate that the difference is small and convergence is rapid. [ABSTRACT FROM AUTHOR]

Purpose |!|#8211; The purpose of this paper is to establish an orbital launch window for manned Moon-to-Earth trajectories to support China|!|#39;s manned lunar landing mission requirements of high-latitude landing and anytime return, i.e. the capability of safely returning the crew exploration vehicle at any time from any lunar parking orbit. The launch window is a certain time interval during which the transearth injection may occur and result in a safe lunar return to the specified landing site on the surface of the Earth. Design/methodology/approach |!|#8211; Using the patched conic technique, an analytical design method for determining the transearth trajectories is developed with a finite sphere of influence model. An orbital launch window has been established to study the mission sensitivities to transearth trip time and energy requirements. The results presented here are limited to a single impulsive maneuver. Findings |!|#8211; The difference between the results of the analytical model and high-fidelity model is compared. This difference is relatively small and can be easily eliminated by a simple differential correction procedure. The launch window duration varies with launch date, from less than one hour to greater than 20|!|#8201;h, and the launch window occurs every day in the sidereal month. Research limitations/implications |!|#8211; The solution can be used to serve as an initial estimate for future optimization procedures. Practical implications |!|#8211; The orbital launch window can be used to provide the basis for the preparation of an orbital launch timetable compatible with lunar missions and re-entry conditions requirements. Originality/value |!|#8211; Previous studies were mainly concentrated on the launch windows for the departure from the Earth. This paper investigates and establishes the orbital launch window for Moon-to-Earth trajectories. [ABSTRACT FROM AUTHOR]

Aiming at the complexity of the glioma classification process, a classification framework based on SE‐ResNeXt network is proposed to simplify the classification process of benign and malignant of gliomas. In addition, three optimization strategies are adopted to improve the accuracy. Firstly, the MultiStepLR strategy is used to adjust the learning rate dynamically in order to improve the learning ability of the network. Secondly, the one‐hot label is optimized by the label smoothing strategy which can reduce the dependence of the network on the probability distribution of real labels and improve the prediction ability of the network. Finally, the transfer learning process is simplified by the transfer learning strategy on CE‐MRI dataset, and the generalization ability of the network is improved. The experimental results show that the accuracy, sensitivity, specificity and AUC of the proposed method reach 97.45%, 98.35%, 94.93% and 0.9966 for the BraTS2017 dataset, 98.99%, 99.18%,98.33% and 0.9993 for the BraTS2019 dataset, respectively. Compared with the classical networks and other algorithms, the classification framework proposed in this paper has the best performance on glioma classification. [ABSTRACT FROM AUTHOR]

Straw return is considered an effective way to improve the soil organic carbon (SOC) content of farmland. Most studies have suggested that a straw application increases the SOC content; however, some suggest that a straw application reduces the SOC content when used in combination with mineral fertilisation. Therefore, a meta-analysis of the effect of a straw application on the SOC change is needed. This study comprises a meta-analysis of 115 observations from 65 research articles worldwide. Straw applications can significantly increase the proportion of the SOC in the soil. Straw applications caused a significant microbial biomass carbon (MBC) increase in tropical and warm climatic zones. The MBC increase was higher than the SOC increase. For agriculture, the most important soil functions are the maintenance of the crop productivity, the nutrient and water transformation, the biological flora and activity, and the maintenance of the microbial abundance and activity. These functions should be prioritised in order to maintain the SOC function and services. Straw applications should not be excessive, especially when combined with mineral fertilisation, in order to avoid the loss of carbon from the straw in the form of greenhouse gases. A large amount of unused fertiliser also leads to a series of environmental problems. [ABSTRACT FROM AUTHOR]

The production of hybrid progeny through distant hybridization holds great significance in enriching germplasm resources for fish breeding. In this study, a hybridization experiment was conducted between female KOC (Cyprinus carpio haematopterus) and male GR (Gobiocypris rarus), resulting in the production of two distinct types of hybrid offspring. These progenies were classified as allodiploid and allotriploid based on their DNA content and chromosome numbers, hereafter referred to as CG and CCG. Subsequently, a comprehensive comparative analysis was performed between the CG and CCG hybrids and their parents, focusing on countable traits, measurable traits, erythrocyte morphology, as well as karyogene and mitochondrial gene composition. The majority of the examined countable and measurable traits in both CG and CCG exhibited similarities predominantly with GR, except for the ratios of body length (BL) to body height (BH) and head length (HL). Moreover, observing erythrocytes revealed the presence of dumbbell-shaped nuclei in CCG, a characteristic not observed in CG hybrids or the parents. Sequencing alignment revealed that the homeobox (Hox) genes and 5S RNA in CG and CCG were inherited from both KOC and GR, signifying their status as allodiploid and allotriploid organisms. The mitochondrial genes in CG and CCG showed substantial similarity to KOC, albeit with a few sites displaying paternal leakage inheritance from GR. In comparison to CG, the growth rate of CCG was found to be significantly faster, which could be attributed to the upregulation of growth hormone 1 (gh1) and the downregulation of myostatin b (mstn). This study successfully produced two hybrid offspring with distinct growth characteristics but similar genetic backgrounds, making them ideal subjects for future investigations into growth traits. The findings of this research established a fundamental basis for investigating the growth mechanism of fish and provided significant implications for the advancement of fish breeding through hybridization. [ABSTRACT FROM AUTHOR]

This paper intends to establish a blade element momentum theory (BEMT) model for analyzing the rotor-and-rotor interference in the hovering intermeshing rotor system. The model uses the blade tip/hub losses to portray the intrinsic three-dimensional rotor aerodynamic effects and introduces the skew downwash flow to determine the rotor-and-rotor interference. Then, the model employs the interference locus considering the intersecting angle and the rotor hub spacing to distinguish the interference operating region on the rotor disk. Next, the BEMT model results are validated against experimental data of the German Autonomous Rotorcraft for Extreme Altitudes (AREA) helicopter and the computational fluid dynamics simulation results of the JZ series helicopters. Moreover, the effects of the rotor performance on the intersecting angle are also considered. It is found that the interference operating region resembles a semi-ellipse shape on the intermeshing rotor disk, which is not sensitive to the collective pitch angles under given structural parameters. Second, the emerging thrust recovery region created by raising the intersecting angle from 20 to 30 deg has a limited enhancement to the rotor thrust and the rotor performance. However, the incremental intersecting angle will produce a significant variation of the rotor thrust in the horizontal component in the body coordinate system, providing a large design numerical margin for the lateral stability in the hovering intermeshing rotor system. [ABSTRACT FROM AUTHOR]

Banana is one of the most important crops in tropical and subtropical regions of China. Fenjiao( Musa Spp. ABB, Pisang Awak subgroup) has been grown by small scale famers because of its stable market price and better sugar-acid blend. However, the traditional Fenjiao variety is susceptible to banana Fusarium wilt, has a high plant height( over 5. 0 m), and farmers lack large-scale planting techniques.Based on the traditional Fenjiao variety, we selected 'Refen 1' variety through mutagenesis technology, which has low temperature resistance, suitable to marginal soils and relatively low plant height( 3. 2-4. 0 m). This paper mainly introduces the major techniques of propagation, cultivation, and post-harvest stages of'Refen 1'banana, including the selection of explant materials, treatment, disinfection, initial culture, nursery hardening of in vitro-produced banana plants, and transplant of tissue culture seedlings. The major points of the cultivation technology include banana plantation selection and preparation, planting methods, irrigation and fertilizer management, pruning and retaining, and prevention and control of plant diseases and insect pests. [ABSTRACT FROM AUTHOR]

Background: To explore the relationship between college students’ alexithymia and mobile phone addiction as well as the mediating effects of mental health and the moderating role of being a single child or not. Methods: A total of 1034 college students from Changchun were assessed with the Toronto Alexithymia Scale (TAS-20), General Health Questionnaire (GHQ) and Mobile Phone Addiction Index (MPAI). Results: Alexithymia was positively correlated with mental health and mobile phone addiction. Alexithymia had not only a direct impact on mobile phone addiction but also an indirect impact via mental health. For college students who were not only children, higher levels of alexithymia led to an increase in mobile phone addiction, whereas the influence of alexithymia on mobile phone addiction was much weaker among only children. Conclusion: Mental health has a partial mediating effect on the relationship between alexithymia and mobile phone addiction, and the relationship was significantly moderated by whether students were only children or not. [ABSTRACT FROM AUTHOR]

Background: The genetic modification of plant cell walls has been considered to reduce lignocellulose recalcitrance in bioenergy crops. As a result, it is important to develop a precise and rapid assay for the major wall polymer features that affect biomass saccharification in a large population of transgenic plants. In this study, we collected a total of 246 transgenic rice plants that, respectively, over-expressed and RNAi silenced 12 genes of the OsGH9 and OsGH10 family that are closely associated with cellulose and hemicellulose modification. We examined the wall polymer features and biomass saccharification among 246 transgenic plants and one wild-type plant. The samples presented a normal distribution applicable for statistical analysis and NIRS modeling. Results: Among the 246 transgenic rice plants, we determined largely varied wall polymer features and the biomass enzymatic saccharification after alkali pretreatment in rice straws, particularly for the fermentable hexoses, ranging from 52.8 to 95.9%. Correlation analysis indicated that crystalline cellulose and lignin levels negatively affected the hexose and total sugar yields released from pretreatment and enzymatic hydrolysis in the transgenic rice plants, whereas the arabinose levels and arabinose substitution degree (reverse xylose/arabinose ratio) exhibited positive impacts on the hexose and total sugars yields. Notably, near-infrared spectroscopy (NIRS) was applied to obtain ten equations for predicting biomass enzymatic saccharification and seven equations for distinguishing major wall polymer features. Most of the equations exhibited high R2/R2 cv/R2 ev and RPD values for a perfect prediction capacity. Conclusions: Due to large generated populations of transgenic rice lines, this study has not only examined the key wall polymer features that distinctively affect biomass enzymatic saccharification in rice but has also established optimal NIRS models for a rapid and precise screening of major wall polymer features and lignocellulose saccharification in biomass samples. Importantly, this study has briefly explored the potential roles of a total of 12 OsGH9 and OsGH10 genes in cellulose and hemicellulose modification and cell wall remodeling in transgenic rice lines. Hence, it provides a strategy for genetic modification of plant cell walls by expressing the desired OsGH9 and OsGH10 genes that could greatly improve biomass enzymatic digestibility in rice. [ABSTRACT FROM AUTHOR]

Background: Biomass recalcitrance and plant lodging are two complex traits that tightly associate with plant cell wall structure and features. Although genetic modification of plant cell walls can potentially reduce recalcitrance for enhancing biomass saccharification, it remains a challenge to maintain a normal growth with enhanced biomass yield and lodging resistance in transgenic plants. Sucrose synthase (SUS) is a key enzyme to regulate carbon partitioning by providing UDP-glucose as substrate for cellulose and other polysaccharide biosynthesis. Although SUS transgenic plants have reportedly exhibited improvement on the cellulose and starch based traits, little is yet reported about SUS impacts on both biomass saccharification and lodging resistance. In this study, we selected the transgenic rice plants that expressed OsSUS3 genes when driven by the AtCesA8 promoter specific for promoting secondary cell wall cellulose synthesis in Arabidopsis. We examined biomass saccharification and lodging resistance in the transgenic plants and detected their cell wall structures and wall polymer features. Results: During two-year field experiments, the selected AtCesA8::SUS3 transgenic plants maintained a normal growth with slightly increased biomass yields. The four independent transgenic lines exhibited much higher biomass enzymatic saccharification and bioethanol production under chemical pretreatments at P < 0.01 levels, compared with the controls of rice cultivar and empty vector transgenic line. Notably, all transgenic lines showed a consistently enhanced lodging resistance with the increasing extension and pushing forces. Correlation analysis suggested that the reduced cellulose crystallinity was a major factor for largely enhanced biomass saccharification and lodging resistance in transgenic rice plants. In addition, the cell wall thickenings with the increased cellulose and hemicelluloses levels should also contribute to plant lodging resistance. Hence, this study has proposed a mechanistic model that shows how OsSUS3 regulates cellulose and hemicelluloses biosyntheses resulting in reduced cellulose crystallinity and increased wall thickness, thereby leading to large improvements of both biomass saccharification and lodging resistance in transgenic rice plants. Conclusions: This study has demonstrated that the AtCesA8::SUS3 transgenic rice plants exhibited largely improved biomass saccharification and lodging resistance by reducing cellulose crystallinity and increasing cell wall thickness. It also suggests a powerful genetic approach for cell wall modification in bioenergy crops. [ABSTRACT FROM AUTHOR]

The objective of the present study is to determine whether methoxychlor (MXC) exposure in adulthood affects rat Leydig cell regeneration and to compare its effects with estradiol (E2). Adult 90-day-old male Sprague-Dawley rats received ethane dimethane sulfonate (EDS) to eliminate the adult Leydig cell population. Subsequently, rats were randomly assigned to four groups and gavaged with corn oil (control), 0.25 mg/kg E2 and 10 or 100 mg/kg MXC daily from days 5 to 30 post-EDS treatment. The results showed that MXC and E2 reduced serum testosterone levels on day 58 post-EDS treatment. qPCR showed Hsd17b3 mRNA levels were downregulated 7-15 fold by E2 and MXC, indicating that development of the new population of Leydig cells was arrested at the earlier stage. This observation was supported by the results of histochemical staining, which demonstrated that Leydig cells in MXC-treated testis on day 58 post-EDS treatment were mostly progenitor Leydig cells. However, Pdgfb mRNA levels were downregulated, while Lif transcript levels were increased by MXC. In contrast, E2 did not affect gene expression for these growth factors. In conclusion, our findings indicated that both MXC and E2 delayed rat Leydig cell regeneration in the EDS-treated model, presumably acting by different mechanisms. [ABSTRACT FROM AUTHOR]