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Based on sketching techniques, we propose two practical randomized algorithms for tensor ring (TR) decomposition. Specifically, on the basis of defining new tensor products and investigating their properties, the two algorithms are devised by applying the Kronecker sub‐sampled randomized Fourier transform and TensorSketch to the alternating least squares subproblems derived from the minimization problem of TR decomposition. From the former, we find an algorithmic framework based on random projection for randomized TR decomposition. We compare our proposals with the existing methods using both synthetic and real data. Numerical results show that they have quite decent performance in accuracy and computing time. [ABSTRACT FROM AUTHOR]

Tensor ring (TR) decomposition has been widely applied as an effective approach in a variety of applications to discover the hidden low‐rank patterns in multidimensional and higher‐order data. A well‐known method for TR decomposition is the alternating least squares (ALS). However, solving the ALS subproblems often suffers from high cost issue, especially for large‐scale tensors. In this paper, we provide two strategies to tackle this issue and design three ALS‐based algorithms. Specifically, the first strategy is used to simplify the calculation of the coefficient matrices of the normal equations for the ALS subproblems, which takes full advantage of the structure of the coefficient matrices of the subproblems and hence makes the corresponding algorithm perform much better than the regular ALS method in terms of computing time. The second strategy is to stabilize the ALS subproblems by QR factorizations on TR‐cores, and hence the corresponding algorithms are more numerically stable compared with our first algorithm. Extensive numerical experiments on synthetic and real data are given to illustrate and confirm the above results. In addition, we also present the complexity analyses of the proposed algorithms. [ABSTRACT FROM AUTHOR]

Objective: To estimate whether genetically proxied periodontitis causally impacts the brain cortical structure using Mendelian randomization (MR). Background: Periodontitis is one of the most prevalent inflammatory conditions globally, and emerging evidence has indicated its influences on distal organs, including the brain, whose disorders are always accompanied by magnetic resonance imaging (MRI)‐identified brain cortical changes. However, to date, no available evidence has revealed the association between periodontitis and brain cortical structures. Methods: The instrumental variables (IVs) were adopted from previous genome‐wide association study (GWAS) studies and meta‐analyses of GWAS studies of periodontitis from 1844 to 5266 cases and 8255 to 12 515 controls. IVs were linked to GWAS summary data of 51 665 patients from the ENIGMA Consortium, assessing the impacts of genetically proxied periodontitis on the surficial area (SA) or the cortical thickness (TH) of the global and 34 MRI‐identified functional regions of the brain. Inverse‐variance weighted was used as the primary estimate; the MR pleiotropy residual sum and outlier (MR‐PRESSO), the MR–Egger intercept test, and leave‐one‐out analyses were used to examine the potential horizontal pleiotropy. Results: Genetically proxied periodontitis affects the SA of the medial orbitofrontal cortex, the lateral orbitofrontal cortex, the inferior temporal cortex, the entorhinal cortex, and the temporal pole, as well as the TH of the entorhinal. No pleiotropy was detected. Conclusions: Periodontitis causally influences the brain cortical structures, implying the existence of a periodontal tissue–brain axis. [ABSTRACT FROM AUTHOR]

Silicide ceramics are attracted significant attention due to their exceptional physical properties. However, their inherent brittleness at room temperature limits their practical applications. Here, we aim to improve the mechanical properties of tantalum disilicide (TaSi2) ceramics by modifying the preparation methods and sintering conditions. We fabricate the dense TaSi2 ceramics using high‐pressure and high‐temperature (HPHT) sintering technology at 5.5 GPa and 800–1300°C. We characterize the microstructures, mechanical, and electronic properties of bulk TaSi2 ceramics at HPHT conditions. Our results indicate an enhancement in the fracture toughness of 11.97 MPa m1/2 for TaSi2 ceramics. More importantly, the electrical conductivity (47.13 × 105 S/m) of TaSi2 ceramic is increased and verified by theoretical calculations. These findings provide crucial insights for future applications of TaSi2 and offer valuable avenues for the design and synthesis of advanced ceramic materials. [ABSTRACT FROM AUTHOR]

For tensor linear systems with respect to the popular t‐product, we first present the sketch‐and‐project method and its adaptive variants. Their Fourier domain versions are also investigated. Then, considering that the existing sketching tensor or way for sampling has some limitations, we propose two improved strategies. Convergence analyses for the methods mentioned above are provided. We compare our methods with the existing ones using synthetic and real data. Numerical results show that they have quite decent performance in terms of the number of iterations and running time. [ABSTRACT FROM AUTHOR]

In this study, ultrafine linear nanostructured SiC with high wettability and large specific surface area were synthesized via the carbothermal reduction method. These nanowires were impregnated with Na2SO4 ⋅ 10H2O, CaCl2 ⋅ 6H2O, MgCl2 ⋅ 6H2O, and CaMg2Cl6 ⋅ 12H2O to obtain composite phase change materials (CPCMs), which demonstrated improved phase separation and significantly reduced supercooling. In particular, the supercooling degree of CaCl2 ⋅ 6H2O was minimized to 0.1 °C. The SiC nanowires effectively prevented issues of dehydration and deliquescence in hydrated salts. The thermal storage capacities of the CPCMs exceeded 90 %, with Na2SO4 ⋅ 10H2O and MgCl2 ⋅ 6H2O reaching 107.10 % and 103.35 %, respectively. Furthermore, the CPCMs exhibited greater sensitivity to changes in temperature compared with the pure hydrated salt phase change materials (PCMs). These results indicate that ultra‐fine SiC nanowires can act as a versatile carrier for hydrated salt PCMs at low and intermediate temperatures. [ABSTRACT FROM AUTHOR]

A colorimetric assay for the determination and quantification of ascorbic acid (AA) is presented using silver nanoparticle (AgNP) single‐walled carbon nanotube (AgNP/SWCNT) nanocomposites prepared using a microwave‐assisted method. The AgNP/SWCNT nanocomposites possessed oxidase‐like properties toward 3,3′,5,5′‐tetramethylbenzidine (TMB) and could catalyze the oxidation of TMB to form a blue oxidation product (λmax = 652 nm) in the absence of H2O2. AA can specifically inhibit the oxidation of TMB, resulting in a decline of the absorbance value and blue colour fading. As such, amounts of AA can be assessed easily by the unaided eye and quantitatively using an ultraviolet–visible light spectrophotometer. Under the optimal reaction conditions, this strategy showed a good linearity ranging from 0.4 μM to 5.0 μM for AA detection, and the limit of detection was 130 nM. This assay was also applied for AA measurement in vitamin C tablets and juice samples that yielded satisfactory results. [ABSTRACT FROM AUTHOR]

BACKGROUND Sauce braised meat products are popular in Asia, although their complicated processing may lead to potential safety risks. Especially, how hazardous compounds are formed during their preparation is still unclear. In the present study, braised chicken breasts, which are a typical Chinese sauce braised meat product, were used to investigate the formation of heterocyclic amines (HCAs) during heat treatment. RESULTS: Precursor content (creatine and reducing sugar), HCA level and temperature were measured in different parts of the chicken breast at each processing stage. The results obtained showed that the increasing trends of total HCA content in different parts of chicken breast were not the same. Only total HCA content in the skin (4.93 ± 0.80 ng g−1) increased significantly after deep‐frying. During braising, total HCA level in the skin was high (12.1–14.3 ng g−1) and relatively stable. However, total HCA content in pectoralis major muscle (3.90–7.40 ng g−1) and pectoralis minor muscle (1.44–5.31 ng g−1) was much lower than in the skin, and increased steadily with braising time. CONCLUSION: Braising is the main factor which affects HCA level in braised chicken. Combining the results of temperature and precursor content, a possible explanation for the large amount of HCAs in braised chicken is the gradual infiltration from reused marinade, instead of thermic generation. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A stroke segmentation method named quick penalty-based dynamic programming is proposed for splitting a sketchy stroke into several regular primitive shapes, such as line segments and elliptical arcs. The authors extend the dynamic programming framework with a customisable penalty function, which measures the correctness of splitting a stroke at a particular point. With the help of the penalty function, the proposed dynamic programming framework can finish the stroke segmentation process without any prior knowledge of the number and/or the type of segments contained in the sketchy stroke. Its response time is sufficiently short for online applications, even for long strokes. Experiments show that the proposed method is robust for strokes with arbitrary shape and size. [ABSTRACT FROM AUTHOR]