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Mobile edge computing (MEC) is considered one of the key technologies for large-scale network services. Task scheduling helps to improve the task completion rate of MEC, by properly mapping tasks generated by devices onto MEC resources. However, the mobility of devices introduces complexities, potentially resulting in failed task offloading or unavailable task results. To tackle this issue, we propose a mobile-aware task scheduling scheme. We first model the trajectory of mobile devices and introduce a strategy for the fastest task offloading, coupled with an efficient result return method. Subsequently, to improve the task completion rate, we present a task scheduling model based on task migration and formulate the relevant problem as a Mixed Integer Non-linear Programming (MINLP) problem. To achieve a solution within a reasonable time complexity, we propose a Particle Swarm Optimization and Genetic Algorithm with a Rescheduling operator (PSOGAR). In PSOGAR, particles update their positions using a mating operator, while maintaining diversity by a mutation operator. In addition, a rescheduling operator is used to further improve the task completion rate. Finally, through simulation experiments, compare PSOGAR with state-of-the-art and classic algorithms. The experimental results show that PSOGAR can improve the task completion rate by 18–31% and can be applied to scenarios with tight task deadlines. [ABSTRACT FROM AUTHOR]

Topological insulators are characterized by exhibiting an internal insulating state but a surface conductor state, which makes them advantageous for applications in novel devices. However, for most given acoustic topological metamaterials, the operating frequency is relatively fixed and the effect of temperature on their topological properties is rarely considered. Therefore, a temperature-tunable acoustic topological insulator is constructed in this paper. The quadruple degenerate Dirac cone formed at Γ point can be opened by adjusting the temperature, causing topological band inversion between the doubly degenerate dipolar and quadrupole states, and achieving topological phase transition. The evolution of its topological state with temperature is numerically investigated and a novel topological acoustic waveguide is constructed. The switching effect of temperature on the waveguide device is verified by numerical simulation and experiment. Non-contact active modulation of edge states in the structure is achieved by temperature-controlled topological phases, exhibiting acoustic switching effects. This study can provide corresponding references for the intelligent control of acoustic topology in noise, vibration, and other aspects. [ABSTRACT FROM AUTHOR]

Modeling user intention with limited evidence in short-term historical sequences is a major challenge in session recommendation. In this domain, research exploration extends from traditional methods to deep learning. However, most of them solely concentrate on the sequential dependence or pairwise relations within the session, disregarding the inherent consistency among items. Additionally, there is a lack of research on context adaptation in session intention learning. To this end, we propose a novel session-based model named C-HAN, which consists of two parallel modules: the context-embedded hypergraph attention network and self-attention. These modules are designed to capture the inherent consistency and sequential dependencies between items. In the hypergraph attention network module, the different types of interaction contexts are introduced to enhance the model's contextual awareness. Finally, the soft-attention mechanism efficiently integrates the two types of information, collaboratively constructing the representation of the session. Experimental validation on three real-world datasets demonstrates the superior performance of C-HAN compared to state-of-the-art methods. The results show that C-HAN achieves an average improvement of 6.55%, 5.91%, and 6.17% over the runner-up baseline method on Precision@K, Recall@K, and MRR evaluation metrics, respectively. [ABSTRACT FROM AUTHOR]

Double-layer island working face main roadway coal pillars are affected by complex mining stress superposition, when different coal pillar width combinations, the surrounding rock stress field will produce different degrees of regional loading increase effect; the study of the surrounding rock stress field regional superposition loading increase law is meaningful to explaining the failure mode of the roadway and determining the critical control area. This study combines numerical simulation with on-site monitoring and other methods and draws the following conclusions: The superimposed loading increase law (“decreasing” → “increasing”) of the abutment pressure and deviatoric stress in the lower coal seam of the double-layer island working face during the mining; the type of the principal stress deflection in the advance working face region; and by obtaining the three types of development morphology of the deviatoric stress peak zone of the roadway and its corresponding nine evolution modes (one type of circular tube → four types of inverse hyperbolic body → four types of hyperbolic body) in the double-layered island working face mining. Indicated the critical reinforcement area corresponding to the main roadway when at different combinations of coal pillar widths; determined the main track roadway protective coal pillars width for 40 m and the shape of the roadway peak deviatoric stress zone is the inverse class hyperbolic body mode; according to the evolution mode of the peak deviatoric stress zone, determined the synergistic failure control program for the asymmetric critical zone of the roadway surrounding rock which is a targeted scientific support method; after the feedback of on-site monitoring and, the support program is reasonable and effective. [ABSTRACT FROM AUTHOR]

With the development of "Industry 4.0", artificial intelligence technology is gradually being applied in the steel industry. In actual production, there is a serious lag in viscosity measurement methods. First, this paper used big data technology to analyze and process the viscosity test data and then established prediction models based on the CatBoost model and the LSTM model, respectively, for the viscosity of the titanium-bearing slag. Finally, the information entropy method was used to integrate the results, and an integrated model was established to predict the viscosity of the titanium-bearing slag. The results showed that the integrated model had better performance than the other two single models, with a prediction accuracy of 96.04% and an improvement of 2.06–5.49% compared with the prediction accuracy of the single models. The results show that the integrated model has more practical significance in guiding production practices. [ABSTRACT FROM AUTHOR]

Objective: To investigate the distribution characteristics of intestinal flora in patients with obstructive sleep apnoea hypopnea syndrome (OSAHS) of different severities and the relationship between different intestinal flora and sleep structure disorder, hypoxemia and obesity. Methods: A total of 25 healthy volunteers and 80 patients with OSAHS were enrolled in this study. The control group was healthy, and the experimental group comprised patients with OSAHS. The apnoea–hypopnea index (AHI), minimum saturation of peripheral oxygen (SpO2min), mean saturation of peripheral oxygen, body mass index, maximum apnoea time and other indicators were collected in clinical practice. The patients with OSAHS were divided into 20 mild and 42 moderate OSAHS cases, as well as 18 patients with severe OSAHS according to the AHI classification. Bioinformatics-related statistics were analysed using the QIIME2 software, and clinical data were analysed with the SPSS 22.0 software. Results: The changes in microbial alpha diversity in the intestinal flora of patients with OSAHS showed that richness, diversity and evenness decreased, but the beta diversity did not change significantly. The Thermus Anoxybacillus, Anaerofustis, Blautia, Sediminibacterium, Ralstonia, Pelomonas, Ochrobactrum, Thermus Sediminibacterium, Ralstonia, Coccidia, Cyanobacteria, Anoxic bacilli and Anaerobes were negatively correlated with AHI (r = −0.38, −0.36, −0.35, −0.33, −0.31, −0.29, −0.22, −0.18) and positively correlated with SpO2min (r =0.38, 0.2, 0.25, 0.22, 0.24, 0.11, 0.23, 0.15). Conclusion: Some bacteria showed a significant correlation with clinical sleep monitoring data, which provides a possibility for the assessment of disease risk, but the mechanisms of their actions in the intestinal tract are not clear at present. Further research and observations are needed. [ABSTRACT FROM AUTHOR]

Energy evolution is of great significance for exposing the failure mechanism of coal reservoirs and evaluating the fracturing effect. This study conducted uniaxial compression experiments with bedding intersection angle (θ) as a variable, calculated the energy and analyzed their controlling effects on coal deformation, failure and brittleness. The results show that, with increase in θ, the failure mode of coal changes from tensile fracture to shear failure, and the strength, elastic energy (Ue) and total energy (U) of coal all show a trend of first decreasing and then increasing. Based on the comprehensive criteria of the elastic energy ratio (Ue/U) and stress–strain curve, a new division method of the compression stage is proposed, and the determination of the critical point between stages can avoid the influence of human subjective factors. The transformation of Ue and external loads jointly provides the energy source for the release of dissipated energy (Ud). Ue is the main energy type in the pre-peak stage, and a significant amount of energy is converted into Ud in the failure stage. A new brittleness index was constructed by utilizing the relationship between Ue and Ud. It was found that brittleness is negatively correlated with θ and positively correlated with Ue/U at the peak point. A model of the mechanical strength of coal with structured planes has been constructed and validated by experimental data, which can be used to analyze the effect of structural planes on coal strength. When the hydraulic fracturing direction is parallel or at a low angle to the bedding plane, it is favorable for the formation of extensive fractures. [ABSTRACT FROM AUTHOR]

Daylilies (Hemerocallis spp.) are widely cultivated as perennial ornamentals worldwide with important edible, medicinal, and ornamental value. In this study, a total of 9139 SSR loci were detected in the daylily cultivar 'Autumn Red' through Single Molecular Real Time sequencing, of which 2604 unigenes contained two or more SSR loci. Tri-nucleotide repeats were predominated (5270, 57.66%) among the SSR loci, followed by di-nucleotide repeats (3253, 35.50%). Forty (44.44%) valid EST-SSR markers were identified from 90 synthesized EST-SSR markers by screening six accessions, including one daylily wild species, one daylily variant, two daylily cultivars and two night lily landraces cultivated in the National Hemerocallis Germplasm Resource Bank of China. Genetic diversity analysis of 104 Hemerocallis accessions was conducted using 30 polymorphic EST-SSR markers and a total of 98 alleles was identified with an average of 3.23, ranging from 2 to 8 alleles per loci. The polymorphism information content (PIC) values ranged from 0.01 to 0.70, with an average of 0.25. Five markers (XC007, XC057, XC058, XC068 and XC072) showed high polymorphism (PIC > 0.5). Cluster analysis showed that daylilies and night lilies were clustered into two phylogenetic groups, which was confirmed by population structure analysis and PCoA analysis. Among them, Cluster I was classified into six subclusters (Group A–F) in the NJ dendrogram. Combined with the analysis of morphological characteristics of accessions, it was found that the genetic distance may be affected by the source of accessions, which needs further research. Finally, DNA fingerprints of 104 Hemerocallis accessions were constructed using seven efficient EST-SSR markers. The EST-SSRs developed in this study provided useful tools for the identification of daylily accessions and molecular marker assisted breeding. [ABSTRACT FROM AUTHOR]

Graphene, with its two linearly dispersing Dirac points with opposite windings, is the minimal topological nodal configuration in the hexagonal Brillouin zone. Topological semimetals with higher-order nodes beyond the Dirac points have recently attracted considerable interest due to their rich chiral physics and their potential for the design of next-generation integrated devices. Here we report the experimental realization of the topological semimetal with quadratic nodes in a photonic microring lattice. Our structure hosts a robust second-order node at the center of the Brillouin zone and two Dirac points at the Brillouin zone boundary—the second minimal configuration, next to graphene, that satisfies the Nielsen–Ninomiya theorem. The symmetry-protected quadratic nodal point, together with the Dirac points, leads to the coexistence of massive and massless components in a hybrid chiral particle. This gives rise to unique transport properties, which we demonstrate by directly imaging simultaneous Klein and anti-Klein tunnelling in the microring lattice. Topological semimetals can host coexisting higher-order topological nodes that may enable unique physical properties. Here, based on these topological principles, authors design and experimentally realise simultaneous massive and massless chiral quasiparticles in a photonic microring lattice. [ABSTRACT FROM AUTHOR]

Quantum communication networks are gradually moving toward practicality, and giving rise to the rapid development of quantum information industry. The decentralized quantum distributed communication network (QDCN) based on quantum node information transfer can meet more realistic scenarios, such as direct node information interaction. However, the prerequisite for two nodes to complete secure and stable communication is the establishment of mutual trust evaluation between nodes. In this paper, a practical mutual trust evaluation model in QDCN is proposed to enhance node's privacy and security. Only Bell states measurement and two-qubit projective measurement are needed to complete the trust evaluation between two communication nodes. The quantum circuit diagram required for model building is presented, and the security analysis proved that this model has a better privacy and security performance and higher particle efficiency. [ABSTRACT FROM AUTHOR]

Lithology identification is an important task in oil and gas exploration. In recent years, machine learning methods have become a powerful tool for intelligent lithology identification. To address the redundancy of conventional logging data and unbalanced distribution among formation lithology classes due to the complexity of depositional environment and inhomogeneity of subsurface space, this paper investigates the affiliation-weighted one-to-one support vector machine (WOVOSVM) lithology identification method based on geochemical logging data. This method uses geochemical logging data, which can directly reflect the formation lithology information, as input, and achieves intelligent and accurate lithology classification under the calculation of WOVOSVM. In this study, Shahezi Formation of Songke 2 Well in Songliao Basin, China is taken as the experimental object, and two data sets with different distribution characteristics are selected as the input. Use WOVOSVM, Adaboost, random forest (RF) and traditional support vector machine (SVM) to identify lithology, and compare and analyze the results. The results are as follows: (1) Accuracy metrics of most of the four classification models were above 60%, indicating the geochemical logging data can effectively reflect the formation lithology information, which is a reliable indicator for the intelligent identification of logging lithology. (2) When the data set has a strong imbalance, the lithology recognition performance of WOVOSVM is better than other methods, the average value of accuracy metrics is more than 72%, F1 value is 8.77% to 14.56% higher than other models, especially in the small sample lithology category recognition, 70% of the samples are correctly classified. [ABSTRACT FROM AUTHOR]

A step towards the next generation of high-capacity, noise-resilient communication and computing technologies is a substantial increase in the dimensionality of information space and the synthesis of superposition states on an N-dimensional (N > 2) Hilbert space featuring exotic group symmetries. Despite the rapid development of photonic devices and systems, on-chip information technologies are mostly limited to two-level systems owing to the lack of sufficient reconfigurability to satisfy the stringent requirement for 2(N − 1) degrees of freedom, intrinsically associated with the increase of synthetic dimensionalities. Even with extensive efforts dedicated to recently emerged vector lasers and microcavities for the expansion of dimensionalities1–10, it still remains a challenge to actively tune the diversified, high-dimensional superposition states of light on demand. Here we demonstrate a hyperdimensional, spin–orbit microlaser for chip-scale flexible generation and manipulation of arbitrary four-level states. Two microcavities coupled through a non-Hermitian synthetic gauge field are designed to emit spin–orbit-coupled states of light with six degrees of freedom. The vectorial state of the emitted laser beam in free space can be mapped on a Bloch hypersphere defining an SU(4) symmetry, demonstrating dynamical generation and reconfiguration of high-dimensional superposition states with high fidelity.A fully integrated semiconductor microlaser that exploits spin–orbit coupling of light emits in a four-dimensional Hilbert space, with flexible control of up to six degrees of freedom. [ABSTRACT FROM AUTHOR]

Social relationships play an important role in improving the quality of recommender systems (RSs). A large number of experimental results show that social relationship-based recommendation methods alleviate the problems of data sparseness and cold start in RSs to some extent. However, existing recommendation methods have difficulty in accurately obtaining user features and item features, which seriously affects recommendation system performance. To accurately model social relationships and improve recommendation quality, we use both explicit (e.g. user-item ratings, trust relationships) and implicit (e.g. social tags) social relationships to mine users' potential interest preferences; thus, we propose a social recommendation method incorporating trust relationships and social tags. The method maps user features and item features to a shared feature space using the above social relationship, obtains user similarity and item similarity through potential feature vectors of users and items, and continuously trains them to obtain accurate similarity relationships to improve recommendation performance. The experimental results demonstrate that our proposed approach achieves superior performance over the other social recommendation approaches. [ABSTRACT FROM AUTHOR]

Larval settlement and metamorphosis are important developmental events in marine invertebrates. Some neuropeptides may play a key role in these processes. In this study, we revealed the expression characteristics of myoinhibitory peptide (MIP) in the embryos and larvae of the echiuran worm Urechis unicinctus using RT-qPCR, in situ hybridization and immunofluorescence techniques, and found its location in the top cells of the upper hemisphere was conservative in larvae. Furthermore, we used the active MIP peptide to verify its role in inducing the larval settlement of U. unicinctus, and confirmed that MIP can trigger an obvious larval settlement when 10 µmolL−1 or 15 µmolL−1 MIP was added in the seawater where early-segmentation larvae were cultured. Our finding indicated that neuropeptide MIP participates in the larval settlement in U. unicinctus. [ABSTRACT FROM AUTHOR]

Small colony variants (SCVs) are a slow-growing subpopulation of bacteria characterized by their atypical colony morphology and distinct biochemical properties, which are known to cause chronic persistent infections. Here, we investigated the characteristics of three phenotypes of Escherichia coli, including a capnophilic SCV, co-isolated from a 64-year-old patient with bacteremia in China. The three strains were identified as a capnophilic strain (EC1), a capnophilic SCV (EC2), and a normal colony strain (EC3). The EC1 and EC2 strains did not grow in the absence of CO2, while the EC2 colonies were pinpoint in appearance and had the ability to revert to the normal colony phenotype. The growth of the SCV was slow and not enhanced in the presence of thymidine, hemin, thiamine, and menadione. The results of antimicrobial susceptibility among the three strains showed similar sensitivity to cefoxitin and imipenem, but resistant to most of the other antimicrobials tested. Whole-genome sequencing showed that no genetic mutational variations associated with SCVs were observed, while EC1, EC2 and the revertible strains of EC2 lacked the can gene. Multi-locus sequence typing showed that all strains belonged to ST457 and nucleotide similarity analysis indicated that they had high homology. In conclusion, we report rarely described co-isolated forms of three phenotypes of E. coli that included a capnophilic SCV in a patient with bacteremia. The capnophilic SCV strain had atypical morphology and biochemical characteristics in the absence of can gene. Based on our findings, we have discussed the laboratory identification, characterization, mechanisms, and clinical treatment of capnophilic SCV strains. [ABSTRACT FROM AUTHOR]

The model predictive current control (MPCC) method is considered to be one of the most effective methods to solve the dual three-phase permanent magnet synchronous motor driving problem. However, the existing traditional MPCC method is limited. In some cases, inaccuracies in the selected optimal voltage vector (Vopt) can lead to additional current ripple and unsatisfactory steady-state performance, and the MPCC method needs to carry out the traversal optimization process, which increases the computational burden. To solve the above problem, this paper proposes an MPCC method based on an extended finite control set and duty cycle modulation. Firstly, 12 virtual voltage vectors (V3s) with new directions are synthesized, and an extended control set containing 24 V3s is constructed to effectively reduce harmonic current and torque ripple. Then, the dead-beat current control is used to calculate the sector of the reference voltage vector (Vref), and the Vopt is selected by judging the position of the sector, which reduces the calculation burden. More importantly, the technique of duty cycle modulation is put forward to calculate the residence time of the Vopt, aiming to amend the Vopt magnitude, which can improve the control accuracy. For ease of understanding and software implementation on Digital Signal Processors, triangular carriers are used to generate asymmetric switching sequences. Finally, the experimental results show that the proposed method has better current quality and lower torque ripple than the two existing methods, and the calculation burden is reduced. [ABSTRACT FROM AUTHOR]

Purpose: Iron (Fe) deficiency seriously affects crop growth and yield. This study investigated whether and how an endophytic isolate, strain Bacillus sp. WR12, alleviates Fe deficiency in wheat (Triticum aestivum L.). Methods: Bacillus sp. WR12 and wheat seedlings were hydroponically co-cultured for 2 weeks under Fe-deficient conditions. To evaluate the Fe deficiency alleviating potential, wheat growth parameters were compared. To elucidate possible mechanisms, the genome of WR12 was sequenced, and production of siderophores was detected. In addition, transcriptomes of wheat root were compared, and accumulation of phenolic compounds was measured. Results: Bacillus sp. WR12 significantly increased root length and dry weight, leaf chlorophyll content and Fe content in Fe-deficient wheat seedlings. Genome analysis of WR12 and CAS agar diffusion test demonstrated that WR12 had a dhbACEBF operon and produced siderophores. Significant upregulation of this operon and more siderophore synthesis in WR12 were observed when Fe was insufficient. Transcriptomic data of roots indicated change of expression of a large number of genes in Fe-deficient wheat after WR12 inoculation. Particularly, PAL, CYP73A, COMT, F5H, HCT and CAD genes involved in phenylpropane biosynthesis were significantly up-regulated. Moreover, elevated phenol accumulation was detected in the root of wheat after inoculation with WR12 under Fe deficiency. Conclusions: Bacillus sp. WR12 alleviates Fe deficiency in wheat and this can be partially attributed to enhanced siderophore production and phenol accumulation. [ABSTRACT FROM AUTHOR]

An innovative melt treatment method known as internal electromagnetic stirring is proposed and used in direct chill casting to refine the microstructure and homogenize the composition of a large-scale 7075 aluminum alloy billet. The effects of internal electromagnetic stirring on the billet are investigated. The results show that the internal electromagnetic stirring significantly refines the microstructure and decreases macrosegregation compared with conventional direction chill casting. The average grain size is decreased to 211–219 μm, and the largest relative positive and negative macrosegregation rates of Zn, Mg, and Cu are decreased to 2.44% and 2.11%, 1.56% and 1.32%, and 2.64% and 1.98%, respectively. The internal electromagnetic stirring refines the microstructure by increasing the number of nuclei, creating a relatively low and homogeneous temperature field, and decreasing the sump depth. Furthermore, the internal electromagnetic stirring decreases the macrosegregation by inhibiting the thermo-solutal convection, strengthening the equivalent shrinkage-induced flow, and decreasing the permeability. [ABSTRACT FROM AUTHOR]

Bilingual word embeddings (BWEs) play a very important role in many natural language processing (NLP) tasks, especially cross-lingual tasks such as machine translation (MT) and cross-language information retrieval. Most existing methods to train BWEs are based on bilingual supervision. However, bilingual resources are not available for many low-resource language pairs. Although some studies addressed this issue with unsupervised methods, monolingual contextual data are not used to improve the performance of low-resource BWEs. To address these issues, we propose an unsupervised method to improve BWEs using optimized monolingual context information without any parallel corpora. In particular, we first build a bilingual word embeddings mapping model between two languages by aligning monolingual word embedding spaces based on unsupervised adversarial training. To further improve the performance of these mappings, we use monolingual context information to optimize them during the course. Experimental results show that our method outperforms other baseline systems significantly, including results for four low-resource language pairs. [ABSTRACT FROM AUTHOR]

An efficient and widely tunable Si-prism-array coupled terahertz-wave parametric oscillator (TPO) with a very narrow linewidth is demonstrated by using a shallow surface cross-pump configuration. The shallow surface cross-pumping form was realized by totally reflect the pump beam at the THz-wave exit surface. Widely THz-wave tuning range of 0.6–3.9 THz is realized with a 1-mm diameter pump, and the high-frequency end even reached 5.5 THz with a 2-mm diameter pump to increase the nonlinear gain length. The measured Stokes linewidth was 0.07 nm, which is compressed by 70% for that of the conventional TPOs. The highest THz-wave output energy of 2.4 μJ was achieved at 2 THz under 15 mJ pumping, corresponding to an energy conversion efficiency of 1.6 × 10−4. The mechanism of the frequency-selection effect in cross-pumped stimulated polariton scatterings was discussed by calculating the single-pass parametric gain for different phase mismatches. [ABSTRACT FROM AUTHOR]

In order to further improve the accuracy of land use classification, this paper uses UC Merced land use data set to fine-tune the parameters of CaffeNet, VGG-S, and VGG-F CNN models. Then, the fine-tuned network is used as the feature extractor, and the extracted full connection layer output features are cascaded as the final expression of the image. Finally, the cascaded features are input into the mcODM classifier to obtain the classification results. The results showed that the overall classification accuracy of the multi-structure CNN feature cascade method in UC Merced landuse dataset reached 97.55%, indicating an improvement between 2 and 5% compared with the single CNN model, and the classification accuracy after fine-tuning was improved in the range of 3–5%. In conclusion, this method can effectively improve the expression of features in scene level classification and improve classification performance. [ABSTRACT FROM AUTHOR]

For pre-operative osteoarthritis (OA) patients with varus knee, previous studies showed inconsistent results. Therefore, we conducted this study to better identify the association of Hospital for Special Surgery (HSS) score and mechanical alignment. 44 patients (51 knees) with constitutional varus knee caused by combined deformities (LDFA (lateral distal femoral angle) > 90°and MPTA (medial proximal tibial angle) < 85°)) were selected and analyzed with a mean follow-up period of 14 months after total knee arthroplasty (TKA). From January 2015 to December 2016, patients were collected consecutively after primary TKA. After filtering, fifty-one knees (44patients) were analyzed with a mean follow-up period of 14 months. All patients were divided into two groups based on post-operative hip-knee-ankle (HKA) acute angle: varus mechanical alignment (VMA) group (HKA < − 3°) and neutral mechanical axis (NMA) group (− 3° ≤ HKA ≤ 3°). 30 knees were included in the NMA group, and 21 knees in the VMA group. Comparisons of HSS between NMA group and VMA group were performed. After adjusting for age and Body Mass Index (BMI) confounders, Compared with NMA group, the HSS score in VMA group decreased by 0.81 units (95% CI, − 3.37 to 1.75) p = 0.5370). For pre-operative constitutional varus knee caused by combined deformities in chinese populations, no significant association between post-operative lower limb mechanical alignment and HSS score was found. [ABSTRACT FROM AUTHOR]

Recently, N-nitrosamines have been unexpectedly found in generic sartan products. Herein, we developed a sensitive and stable GC-MS/MS method with multiple reactions monitoring mode for the simultaneous determination of four N-nitrosamines in sartan substances, namely, N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodibutylamine, and N-nitrosodiisopropylamine. The conditions of gas chromatography and mass spectrometry were optimized. The method was validated according to the International Council for Harmonization guidelines in terms of sensitivity, linearity, accuracy, precision, specificity, and stability. The limits of detection of N-nitrosamines in sartan substances ranged from 0.002 to 0.150 ppm, and the corresponding limits of quantification were in the range of 0.008-0.500 ppm, which met the sensitivity requirements for the limits set by the Food and Drug Administration of the United States. The internal standard curve of four N-nitrosamines showed good linearity of regression coefficients over 0.99. The recoveries of N-nitrosamines in selected sartan drugs ranged from 87.68 to 123.76%. The intraday and interday relative standard deviation values were less than 9.15%. Therefore, this proposed method exhibited good sensitivity and precision, high accuracy, and fast analysis speed, which provide a reliable method for quality control of N-nitrosamines in sartan products. [ABSTRACT FROM AUTHOR]

A numerical simulation is carried out to investigate the effect of the stirring position on large-sized 7005 alloy billet prepared by direct chill casting imposed with A-EMS and intercooling named uniform direct chill (UDC) casting. Moreover, the effect of the stirring position on the Lorentz force, fluid flow, heat transfer, and solidification occurring in UDC casting is investigated. It is found that when the stirring position moves upwards, the Lorentz force imparts the forced flow to the melt more effectively. Moreover, when the stirring position increases from 0 mm to 100 mm with respect to the graphite ring level, the maximum convection velocity of the melt increases from 150 mm/s to 210 mm/s. Furthermore, the temperature field of the melt in the sump becomes more homogeneous as the stirring position elevates. The microstructure of the 7005 billets becomes finer and uniform when the stirring position moves up to 50 mm. [ABSTRACT FROM AUTHOR]

The delamination is a typical phenomenon when the carbon fiber reinforced composites (CFRC) undergoes blasting impact loading and the delamination will reduce both the strength and stiffness of the laminates, which can lead to catastrophic consequences while used as rocket skin. In this paper, the response of CFRC laminate is cut by flexible linear shaped charge (FLSC) and the delamination behavior of the CFRC is analyzed and discussed. The displacement interferometer system for any reflector (DISAR) is used to monitor the velocity of characteristic points of the laminate subjected to FLSC. Finite element analysis has been conducted to explain the mechanisms of delamination. Based on the numerical simulation, the influences of structural design parameters on the delamination effect of the CFRC after cutting are investigated. The results show that a large number of debris are produced at the center of the explosion and a small amount of large debris is produced at weakening groove on both sides. The delamination effect is greatly affected by the inter-laminar tensile strength and thickness of composite laminate, but it is not significantly affected by the linear density of the FLSC and stand-off. [ABSTRACT FROM AUTHOR]

Collaborative filtering is the most popular and efficient recommendation algorithm to character the potential preference of the new users, by exploring the patterns of historical consuming records/ratings of the investigated users. There are two types of primary collaborative filtering algorithms: the user-based recommendation system, which recommends items to new users by ranking the similarity of the shared items between the history users and the new users, and the item-based collaborative filtering recommend items to new users by considering the rank of the similarity among all the history items of the training data. Although the collaborative filtering has been successfully applied to many commercial fields, several original drawbacks of collaborative filtering, especially the sparsity of the rating data raises a serious challenge to the accuracy and the universality of those algorithms. In particular, the most rating terms for each specific user are missing in many applications, and the performance of collaborative filtering will be degraded along with the increment of the number of items in training dataset. In this paper, we proposed a novel collaborative filtering method (CBE-CF) to extract the local dense rating modules to cope with the data sparsity and the computational efficiency of the traditional recommendation algorithms, by introducing the information entropy and bi-clustering into collaborative filtering. Here, both the rows and columns of the user-item-rating matrix are clustered together to identify the dense rating modules of the historical records (training) data, and then an information entropy metric is used to quantify the similarity between the new user and each dense modules, and the final prediction is optimized by the aggregative recommendations of the global generalization of item-based methods and the local similarity of the nearest modules. Experimental analysis presents the characters of the proposed CBE-CF, and the precision and the computational cost, etc., are better than state of the art on the benchmark dataset. [ABSTRACT FROM AUTHOR]

The tightly focused field of an incident light beam through cubic phase modulation has been investigated by vectorial diffraction theory. For different modulation index of cubic phase and polarization states of the incident light, the focused fields have been presented. The results show that the Airy-like field can be produced by cubic phase modulation under high numerical aperture (NA) optical system. Intensity pattern and length of the main lobe are depended on modulation index for the spatial uniform polarization, and the Airy-like field is affected by polarization state for the spatial nonuniform polarization. It is helpful to structure new optical fields in optical manipulation, optical imaging, and surface plasma controlling. [ABSTRACT FROM AUTHOR]

The core of the contour-based corner detection is essentially performing a good curvature estimation on planar curves. Inspired by intuitive observation that the curvature of a point on a contour is proportional to the distance accumulation of its neighbors to the tangent of the point, we present a novel curvature estimator named Relative Tangent-to-Point Distance Accumulation (RTPDA) for contour-based corner detection. In the approach, we fit the curve segments with quadratic polynomials by employing least square technique to derive the tangent of the target point, and then accumulate the distance of its neighbors to the tangent, which is a good approximation of the discrete curvature. Experiments verify the effectiveness and the efficiency of the proposed detector in comparison with several influential corner detectors under three commonly used evaluation metrics, namely, Average Repeatability (AR), Localization Error (LE) and Accuracy index (ACU). [ABSTRACT FROM AUTHOR]

Blended cathode materials generally suffer from capacity loss impacting on their power performance in lithium-ion batteries. This work reports a systematic study of LiNi1/3Co1/3Mn1/3O2–LiMn2O4 blended materials incorporated with characterizations of particles, calculations of charging-discharging characters, and analysis of cyclic voltammetry. A synergetic effect, a capacity increasing at high discharging rate referring to the linear superposition of blending components, is observed in a wide blending ratio for blended materials. The model analysis of charging-discharging characters shows that LiMn2O4 releases more reversible capacity in the blended materials than when it is alone at the same electrochemical condition. An equivalent circuit model is proposed to interpret the electrochemical behaviors showed in electrochemical impedance spectroscopy. The mechanism of particle synergetic effect is attributed to the compensating property of blending components, which improves the inter-particles diffusibility of Li+, therefore reduces the particle impedance of blended materials promoting rate performance. Over the blending range, the scheme LiNi1/3Co1/3Mn1/3O2/LiMn2O4–Blend (50:50 in mass ratio) shows the best performance and highest capacity increasing. [ABSTRACT FROM AUTHOR]

An Improved Ant Colony Optimization (IACO) is proposed to design A2-C1 type fuzzy logic system (FLS) in the paper. The design includes parameters adjustment and rules selection, and the performance of the intelligent fuzzy system, which can be improved by choosing the most optimal parameters and reducing the redundant rules. In order to verify the feasibility of the proposed algorithm, the intelligence fuzzy logic systems based on the algorithms are applied to predict the Mackey-Glass chaos time series. The simulations show that both the IACO and ACO have better tracking performances. The results compared with classical algorithm BP ( back-propagation design) shows the tracking performance of IACO is more precise, the result compared with ACO shows that either the training result or the testing result, the tracking performance of IACO is better, and IACO has a faster convergence rate than ACO, the results compared with the Intelligent type-1 fuzzy logic systems show that both the A2-C1 type FLS based on IACO and ACO have better tracking performance than type-1 fuzzy logic system. [ABSTRACT FROM AUTHOR]

A modified three-level laser kinetics model for a pulsed high-power optically pumped gas terahertz laser is introduced and used to model the lasing kinetics process of a gas terahertz laser system. We, for the first time to our knowledge, investigated the time evolution dynamics process of the pump intensity, population distribution among the energy levels, pump and THz signal gain coefficient, and the THz laser intensity within the pulsed D2O gas THz laser. High-power THz pulse with peak power of about 7.4 kW and pulse width of 145 ns at wavelength of 385 μm were obtained in the simulation, using an incident pump pulse with peak power of 2.2 MW and pulse width of 110 ns. THz pulse delay of 40 ns and pulse broadening of 35 ns were quantitatively analyzed. In addition, the experimental results for the pulse profile, pulse width, pulse broadening, pulse energy, and peak power are in agreement with the theoretical simulation results. [ABSTRACT FROM AUTHOR]

The reverse transcription quantitative real-time PCR (RT-qPCR) has become one of the most important techniques of studying gene expression. A set of valid reference genes are essential for the accurate normalization of data. In this study, five candidate genes were analyzed with geNorm, NormFinder, BestKeeper and ΔCt methods to identify the genes stably expressed in echiuran Urechis unicinctus, an important commercial marine benthic worm, under abiotic (sulfide stress) and normal (adult tissues, embryos and larvae at different development stages) conditions. The comprehensive results indicated that the expression of TBP was the most stable at sulfide stress and in developmental process, while the expression of EF-1-α was the most stable at sulfide stress and in various tissues. TBP and EF-1-α were recommended as a suitable reference gene combination to accurately normalize the expression of target genes at sulfide stress; and EF-1-α, TBP and TUB were considered as a potential reference gene combination for normalizing the expression of target genes in different tissues. No suitable gene combination was obtained among these five candidate genes for normalizing the expression of target genes for developmental process of U. unicinctus. Our results provided a valuable support for quantifying gene expression using RT-qPCR in U. unicinctus. [ABSTRACT FROM AUTHOR]

Krüppel-like factor 4 (KLF4) is an important transcription factor involving in formation and maintenance of muscles in mammals. However, no data are available on KLF4 function in shellfish muscles which play vital roles in the movement, stress response, and physiology in shellfish. In the present study, we revealed that the Klf4 mRNA of Zhikong scallop Chlamys farreri was expressed in most tissues, which has high level in adductor muscle, mantle, kidney, and testis. Positive signals of the Klf4 mRNA and protein were visible in all skeletal muscle fibers of adductor muscle, and all the cells of C. farreri mantle. Furthermore, the knockdown of Klf4 mRNA in adductor muscle and mantle by means of in vivo RNA interference led to some different phenotypes, including disordered arrangement of muscle fibers in adductor muscle and mantle, abnormal structures of skeletal muscles, and reduced muscle fibers under endepidermis of mantle. Our findings demonstrated that Klf4 plays important roles in maintenance of muscle functions in C. farreri adductor muscle and mantle, and suggested that its regulatory way in skeletal muscle may be different from the smooth muscle in shellfish. [ABSTRACT FROM AUTHOR]

The production structure of a manufacturing system not only influences its transportation and operation cost, but also affects logistics and parts/machine assignment decisions. Based on the sending and feedback mechanisms of information, the principles of conditional entropy and classical probability are utilized to establish structure entropy models and ordered indices of the system with dynamic characteristics and generality, which provide effective solutions for the absence of quantitative method in evaluating the structural optimization of production system. In an empirical study, this paper analyzes different production structures when workpieces are processed by different working routes before and after the implementation of cellular manufacturing. Afterwards, the developed structure entropy models and ordered indices are utilized to calculate the orderliness of production structure under the two different states. The final result verifies well the validity of this quantitative method for evaluating the orderliness of production structures. [ABSTRACT FROM AUTHOR]

In this work, a molecularly imprinted monolithic column was synthesized by a facile procedure and was applied for specific recognition of domoic acid, an amnesic shellfish poison. The poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) molecularly imprinted monolith was synthesized in a stainless steel column by in situ polymerization. Pentane-1,3,5-tricarboxylic acid was used as a dummy imprinting template instead of the highly toxic and expensive target molecule. It is the first time that a molecularly imprinted monolith is introduced for separation and detection of domoic acid. After optimizing the preparation conditions, the prepared imprinted monolith was systematically characterized and exhibited excellent stability and permeability as a HPLC stationary phase. The results of chromatographic analysis demonstrated that the molecularly imprinted monolith exhibited specific retention and selective recognition toward domoic acid, with an imprinted factor up to 3.77. Furthermore, the molecularly imprinted monolith was successfully applied for selective enrichment of domoic acid from biological samples.A molecularly imprinted monolith was prepared by using a dummy imprinted template and was successfully applied for specific recognition of domoic acid. [ABSTRACT FROM AUTHOR]

Lithium-sulfur battery has been considered as a promising electrochemical energy storage system based on its theoretical energy density. However, its practical application is hindered by poor conductivity of sulfur and the shuttle effect. Herein, a hierarchical three-dimensional nitrogen and phosphorous codoped graphene and carbon nanotubes with 70 wt% of sulfur content (N, P codoped G/CNTs-S70) composite was prepared using melamine phosphate as a single precursor of N and P. The simultaneous introduction of N and P creates high active sites on the G/CNTs backbones, restricts the detachments of sulfur from the host G/CNTs, and induces strong chemical adsorption of the dissolution of lithium polysulfides. The as-prepared N, P codoped G/CNTs-S70 composite delivers a high initial discharge capacity of 1550 mA h g and retains a capacity of 735 mA h g after 200 cycles at 0.5 C. This is a significant improvement in the rate capability and cycling stability compared with the un-doped G/CNTs-S70 cathode. This simple strategy with single precursor offers promising electrochemical properties for Li-S batteries. [ABSTRACT FROM AUTHOR]

To obtain a large-sized, high-quality aluminum alloy billet, an advanced uniform direct chill (UDC) casting method was developed by combining annular electromagnetic stirring (A-EMS) with intercooling in the sump. The 7005 alloy was chosen to investigate the effect of UDC on grain refinement and homogeneity during normal direct chill (NDC) casting. It was concluded that the microstructure consisting of both primary α-Al phase and secondary phases becomes finer and more homogeneous for the billets prepared with UDC casting compared to those prepared with NDC casting, and the forced cooling from both the inner and outer melt under A-EMS has a measurable effect on grain refinement and homogeneity. [ABSTRACT FROM AUTHOR]

Recently, using old or irrelevant images in microblogs to spread false rumors has become increasingly rampant. Therefore, tracking and verifying the sources of images has become essential. In order to solve this problem, this paper provides a real-time, large-scale duplicate image detection method based on multi-feature fusion. This method firstly uses multi-feature fusion to improve retrieval accuracy. Then, by Hbase optimization, it uses a bloom filter and range query to improve retrieval efficiency. Experimental results show that, compared with existing algorithms, this method has higher precision and recall rates. Meanwhile, real-time responsiveness and scalability of the approach also meet real-world needs. [ABSTRACT FROM AUTHOR]

We report on the mid-infrared (MIR) and terahertz (THz) wave spectra of DO gas pumped using a fundamental transverse mode transversely excited atmospheric CO laser with an emission wavelength of 9.26 μm. We obtain MIR emission lines at center wavelengths of 9.262, 9.491, and 9.752 μm, which correspond to the vibrational-energy-level-transition lines of DO. We observe an intense THz stimulated Raman emission line of 385 μm and a weak cascade-transition line of 359 μm for transitions from rotational levels 4 to 4 and 4 to 4 in the first-excited vibration state of the DO molecule gas. We establish a four-energy-level system for modeling the laser kinetics of the dual-wavelength (385 and 359 μm) superradiation THz laser. For the optically pumped DO gas 385 μm THz laser, in considering the cavity effect and insertion loss of a THz cavity oscillator, an approximation treatment of the THz laser kinetics can be made based on a three-energy-level system. [ABSTRACT FROM AUTHOR]

A new laser kinetics model (LKM) of gas Terahertz (THz) laser has been improved and the output characteristics of a pulse gas 385 μm THz laser have been simulated and compared with the associated experimental data. Pump absorption coefficient (PAC) and pulse profile were determined using the experimental method, which provided reliable reference basis for approximated treatment of the model. The equations were solved numerically by the Runge-Kutta numerical method and some THz output characteristics, such as output power, pulse shape and pulse energy were theoretically investigated. The simulation and experimental results are in good agreement. [ABSTRACT FROM AUTHOR]

Outer dense fibers are specific subcellular components of mammal sperm flagella, apart from the axoneme and its associated proteins. As one of the outer dense fibers components, ODF3 is essential for the formation of mammal sperm flagella. In the present study, we isolated the Odf3 gene, 1033 bp in length, from Zhikong scallop Chlamys farreri, which was named as Cf-Odf3. It was predicted that Cf-Odf3 encodes a protein of 240 amino acids which contains 5 discontinuous Pro-Gly-Pro repeats. The Cf-Odf3 transcripts were detected in both testis and ovary of C. farreri at various stages through qRT-PCR. The Cf-ODF3 protein synthesized by prokaryotes was purified using Ni-NTA affinity chromatography and used to produce its polyclonal antibody. The antibody product was effective and specific as was examined by Western blotting. The Cf-Odf3 transcript and Cf-ODF3 protein were located in intragonadal somatic cells (ISCs), spermatogonia and spermatocytes of C. farreri testes, while no transcription of Cf-Odf3 and synthesis of Cf-ODF3 were detected in spermatids and spermatozoa. The location of Odf3 expression is different from that of vertebrates where ODF3 is synthesized specifically in spermatids and sperm flagella. Moreover, the Cf-Odf3 expression was also detected in ISCs, oogonia and oocytes of the scallop ovaries. Our finding revealed a different characteristic of Odf3 expression between scallop and vertebrates, which implied that Cf-Odf3 played a role in the gametogenesis of C. farreri. [ABSTRACT FROM AUTHOR]

This paper presents SWIFT, a computationally intensive DSP Architecture for communication applications. We introduce the VLIW feature and SIMD capability of SWIFT, and the vector register file, store buffer, multi-banked memories as well. Then, the structure of nine stages pipeline with powerful bypass logics is disclosed. Finally, the hardware implementation of SWIFT is shown. In SWIFT, computation, data access and control operation can be handled orthogonally. With the efficient SIMD feature, multi-accessible local data memories, and the fine-tuned VLIW instructions, it is possible to achieve high utilization of the DSP datapath in SWIFT. [ABSTRACT FROM AUTHOR]

LiNiCoMnO, LiMnO and LiCoO are paired to make the blended materials for the cathode of lithium-ion batteries. The factors impacting on the characteristics of blended materials are studied using constant current charge/discharge measurement and electrochemical impedance spectroscopy. The results show that the three pairs of blended materials exhibit very different synergetic effects in high C-rate discharging. The mechanism of particle synergetic effect has a physical root on the compensating material property of blending components, which fundamentally correlates with their similarity and difference in crystalline and electronic structures. The AC impedance show the obvious changes that alternate the high C-rate performance, due to reduced particle impedance in blended materials. The pairs of LiNiCoMnO-LiMnO and LiCoO-LiMnO present obvious increases in high C-rate reversible capacities than does the pair LiCoO-LiNiCoMnO. [ABSTRACT FROM AUTHOR]

Temporal behavior of the pump pulses, residual pump pulses, and THz pulses for optically pumped DO gas molecules was investigated by using a tunable TEA CO laser as the pumping source. The pulse profiles of pump laser pulses, residual pump pulses, and the THz output pulses were measured, simultaneously, at several different gas pressures. For THz pulse, the pulse delay between the THz pulse and the pump pulse was observed and the delay time was observed to increase from 40 to 70 ns with an increase in gas pressure from 500 to 1700 Pa. Both THz pulse broadening and compression were observed, and the pulse broadening effect transformed to the compression effect with increasing the gas pressure. For the residual pump pulse, the full width at half maximum (FWHM) of the main pulse decreased with increasing gas pressure, and the main pulse disappeared at high gas pressures. The secondary pulses were observed at high gas pressure, and the time intervals of about 518 and 435 ns were observed between the THz output pulse and the secondary residual pump pulse at the pressure of 1400 Pa and 1700 Pa, from which the vibrational relaxation time constants of about 5.45 and 5.55 μs Torr were obtained. [ABSTRACT FROM AUTHOR]

Prohibitin (PHB) participates in several biological processes including apoptosis, transcription regulation and suppression of cell proliferation in mammals. In this study, we cloned the full-length cDNA of prohibitin 2 ( Cf-phb2) from the testis of scallop ( Chlamys farreri). The deduced amino acid sequence presented a characteristic of PHB family with the PHB domain, and clustered with PHB2 of other species. Temporal and spatial expression of Cf-phb2 in testis during the reproductive cycle was detected by quantitative real-time PCR (qRT-PCR) and in situ hybridization. The expression of Cf-phb2 in the testis increased when testis developed from the resting stage to mature stage. The mRNA abundance of Cf-phb2 was the highest at mature stage, which was about 15-fold higher than that at proliferative stage. The expression of Cf-phb2 could be detected by in situ hybridization in all types of germ cells in testis, including spermatogonia, spermatocytes, spermatids and spermatozoa. The intensity of the signal increased with the spermatogenesis and was the highest in spermatids, which suggested that CF-PHB2 might affect the spermatogenesis of C. farreri. [ABSTRACT FROM AUTHOR]

The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length cDNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 2194 bp in length with a 981 bp open reading frame encoding 327 amino acids. With real-time PCR analysis, it was detected that Cf-sox2 was expressed in unfertilized oocytes, fertilized eggs and all the tested embryos and larvae. The expression level increased significantly ( P < 0.01) in embryos from 2-cell to blastula, and then decreased significantly ( P < 0.01) and reached the minimum in umbo larva. Moreover, location of the Cf-sox2 expression was revealed using whole mount in situ hybridization technique. Positive hybridization signal could be detected in the central region of unfertilized oocytes and fertilized eggs, and then strong signals dispersed throughout the embryos from 2-cell to gastrula. During larval development, the signals were concentrated and strong signals were restricted to 4 regions of viscera mass in veliger larva. In umbo larva, weak signals could be detected in regions where presumptive visceral and pedal ganglia may be formed. The expression pattern of Cf-sox2 during embryogenesis was similar to that of mammal sox2, which implied that Cf-SOX2 may participate in the regulation of early development of C. farreri. [ABSTRACT FROM AUTHOR]