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Anomaly detection in time series data is crucial for many fields such as healthcare, meteorology, and industrial fault detection. However, traditional unsupervised time series anomaly detection methods suffer from biased anomaly measurement under contaminated training data. Most of existing methods employ hard strategies for contamination calibration by assigning pseudo-label to training data. These hard strategies rely on threshold selection and result in suboptimal performance. To address this problem, in this paper, we propose a novel unsupervised anomaly detection framework for contaminated time series (NegCo), which builds an effective soft contamination calibration strategy by exploiting the observed negative correlation between semantic representation and anomaly detection inherent within the autoencoder framework. We innovatively redefine anomaly detection in data contamination scenarios as an optimization problem rooted in this negative correlation. To model this negative correlation, we introduce a dual construct: morphological similarity captures semantic distinctions relevant to normality, while reconstruction consistency quantifies deviations indicative of anomalies. Firstly, the morphological similarity is effectively measured based on the representative normal samples generated from the center of the learned Gaussian distribution. Then, an anomaly measurement calibration loss function is designed based on negative correlation between morphological similarity and reconstruction consistency, to calibrate the biased anomaly measurement caused by contaminated samples. Extensive experiments on various time series datasets show that the proposed NegCo outperforms state-of-the-art baselines, achieving an improvement of 6.2% to 26.8% in A rea U nder the R eceiver O perating C haracteristics (AUROC) scores, particularly in scenarios with heavily contaminated training data. • Unsupervised time series anomaly detection under data contamination. • Calibrating the biased anomaly measurement by exploiting the negative correlation. • Normal samples from a learned Gaussian distribution to model negative correlation. • Single forward propagation enables anomaly detection using the trained autoencoder. [ABSTRACT FROM AUTHOR]

• LED cooling by thermoelectric cooler integrated microchannel heat sink is proposed. • The relative importance of the factors was revealed by the Taguchi method. • The proposed LED + TEC + WMHS device showed excellent cooling performance. • The LED headlight can be cooled to temperature lower than the coolant temperature. • Cooling system and factor levels for different applications were recommended. Effective thermal management is crucial for light-emitting diodes (LED). Thermoelectric cooler (TEC) and microchannel heat sink (MHS) have been demonstrated to be effective for thermal management of LED. However, neither the combination of these two methods, nor the dominant factors which could be effectively adjusted to control the LED temperature, have been reported. In this study, a cooling device integrating TEC and water-cooled microchannel heat sink (WMHS) is proposed to improve the thermal management of high-power LED headlights. The start-up performance of the proposed device, LED + TEC + WMHS, was evaluated and compared with three different systems, namely LED + WMHS, LED + AHS (air-cooled heat sink), and LED + TEC + AHS. Experimental results have demonstrated the best performance of the LED + TEC + WMHS device. Orthogonal experiments based on the Taguchi method were conducted to reveal dominant factors among four variables, including TEC current, water inlet temperature, water flow velocity, and ambient temperature. The results show that effects of all the factors were significant while the TEC current has most important influence on the performance. The variation of the thermal management performance with the levels of the factors were investigated. The LED temperature was only 60.0 °C even at severe working conditions (T a = 80 °C, T i = 55 °C) and moderate cooling input (I TEC = 2 A, u = 0.49 m/s), indicating great thermal management performance of the proposed method. Choosing a cooling system and adjusting the factor levels for different applications were recommended. [ABSTRACT FROM AUTHOR]

Studies exploring the association of tetrabromobisphenol A (TBBPA) with breast cancer and related mechanisms are limited. To investigate the relationship between TBBPA levels in breast adipose and breast cancer, we carried out case-control research. As well as further examine the mediating role of adipose metabolites between TBBPA and breast cancer using the metabolomics approach. In this study, the concentration of TBBPA was determined utilizing ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) after a solid phase extraction (SPE) pretreatment. High-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was employed to analyze adipose metabolomics. Evaluation of metabolites linked to TBBPA exposure and breast cancer was performed utilizing mediation analysis. With an estimated OR (95%CI) of 1.153 (1.023, 1.299), TBBPA was firmly linked with breast cancer. We also used propensity score matching analysis and sensitivity analysis to reduce the effect of confounding factors on the results. Metabolomics of adipose suggested significant perturbation in the linoleic acid metabolism pathway. In addition, for PC (16:0/16:0) as phospholipids, a mediation effect on the associations of TBBPA exposure with breast cancer risks was observed (estimated mediation percentage: 56.58%). Understanding the relationship between TBBPA exposure and the risk of breast cancer may be facilitated by the findings, which point to potential mediation metabolites. [Display omitted] • First mediation analysis of the relationship between TBBPA and breast cancer risk. • TBBPA were associated with increased risk of breast cancer. • Metabolomics indicated a perturbation of the linoleic acid metabolic pathway. • Phospholipids may mediate the association between TBBPA exposure and breast cancer. [ABSTRACT FROM AUTHOR]

Mo-12Si-8.5B alloy with layered Mo 2 TiAlC 2 (a new MAX phase) additions, in order to improve its fracture toughness, were prepared by hot pressing. The composition analysis combined with microstructure features revealed that after hot pressing sintering, the Mo 2 TiAlC 2 does not decompose but still maintains the layered structure and exhibits a good interface bonding with the matrix. The grain size of Mo-12Si-8.5B alloys was apparently refined by Mo 2 TiAlC 2. The mechanical properties suggested that the Mo 2 TiAlC 2 phase affects the hardness of Mo-12Si-8.5B alloy mainly through grain refinement. As the amount of Mo 2 TiAlC 2 increased, the compressive strength and flexure strength of alloys improved nonlinearly which is caused by the relatively low strength of Mo 2 TiAlC 2 and stress release due to its basal plane sliding, the enhanced strength was attributed to the particle strengthening and fine grain strengthening. The Mo 2 TiAlC 2 phase exhibits a remarkably toughening effect on Mo-12Si-8.5B alloy. The fracture toughness of Mo-12Si-8.5B-2%Mo 2 TiAlC 2 alloy increased by about 52% compared with the Mo 2 TiAlC 2 free alloy. Except for the fine-grain toughening caused by Mo 2 TiAlC 2 particles, the improvement of fracture toughness of Mo-12Si-8.5B alloy by Mo 2 TiAlC 2 is mainly caused by the crack deflection, the steps formed by Mo 2 TiAlC 2 fracture and basal plane (0001) sliding of Mo 2 TiAlC 2. • The layered Mo 2 TiAlC 2 MAX phase was firstly added to Mo-12Si-8.5B alloy. • Mo 2 TiAlC 2 shows a good interface bonding with matrix and refine the grain size. • Compressive and flexure strength improved nonlinearly with Mo 2 TiAlC 2 increasing. • The Mo 2 TiAlC 2 exhibits a remarkably toughening effect on Mo-12Si-8.5B alloy. [ABSTRACT FROM AUTHOR]

Abstract: Assume we have a set of colors and we assign an arbitrary subset of these colors to each vertex of a graph . If we require that each vertex to which an empty set is assigned has in its neighborhood all colors, then this assignment is called the -rainbow dominating function of a graph . The corresponding invariant , which is the minimum sum of numbers of assigned colors over all vertices of , is called the -rainbow domination number of . Brešar and S˘umenjak [B. Brešar, T.K. S˘umenjak On the 2-rainbow domination in graphs, Discrete Applied Mathematics, 155 (2007) 2394–2400] showed that , where for and for . And they raised the question: Is for all ? In this paper, we put forward the answer to the question. More over, we show that , where for and for . [Copyright &y& Elsevier]

Abstract: The generalized Petersen graph is an undirected graph on vertices with and . Fiorini claimed to have determined the crossing numbers of and showed all the values of for up to 14, except 12 unknown values. Lovrečič Saražin proved . Richter and Salazar found a gap in Fiorini’s paper, which invalidated his principal results about , and gave the correct proof for . In this paper, we show the crossing numbers of all for up to 16. [Copyright &y& Elsevier]

China pledges to reach a peak in CO 2 emissions by 2030 and to make its best efforts to reach this peak earlier. Previous studies have paid much attention to the total amount of China's CO 2 emissions, but usually only one dataset is used in each evaluation. The pledged national reduction target is administratively divided into provincial targets. Accurate interpretation of province-level carbon emissions is essential for making policies and achieving the reduction target. However, the spatiotemporal pattern of provincial emissions and the associated uncertainty are still poorly understood. Thus, an assessment of province-level CO 2 emissions considering local statistical data and emission factors is urgently needed. Here, we collected and analyzed 7 published emission datasets to comprehensively evaluate the spatiotemporal distribution of provincial CO 2 emissions. We found that the provincial emissions ranged from 20 to 649 Mt CO 2 and that the standard deviations (SDs) ranged from 8 to 159 Mt. Furthermore, the emissions estimated from provincial-data-based inventories were more consistent than those from the spatial disaggregation of national energy statistics, with mean SDs of 26 and 65 Mt CO 2 in 2012, respectively. Temporally, emissions in most provinces increased from 2000 to approximately 2012 and leveled off afterwards. The interannual variation in provincial CO 2 emissions was captured by provincial-data-based inventories but generally missed by national-data-based inventories. When compared with referenced inventories, the discrepancy for provincial estimates could reach −57%–162% for national-data-based inventories but were less than 45% for provincial-data-based inventories. Using comprehensive data sets, the range presented here incorporated more factors and showed potential systematic biases. Our results indicate that it is more suitable to use provincial inventories when making policies for subnational CO 2 reductions or when performing atmospheric CO 2 simulations. To reduce uncertainties in provincial emission estimates, we suggest the use of local optimized coal emission factors and validations of inventories by direct measurement data and remote sensing results. • Estimates from provincial statistics were more consistent than the national ones. • The interannual variations were well-captured by provincial-data-based datasets. • The provincial-based estimates help to allocate duties and set reduction targets. [ABSTRACT FROM AUTHOR]

Facility agriculture has been widely used around the world due to its effective strategy of increasing the added value of agricultural products. The study of Mn4+ doped oxidized red phosphors has become a prominent area of research aimed at addressing the shortage of red light in agriculture and horticulture. In this work, SrZnAl 10 O 17 far-red phosphors doped with Mn4+ were deliberately designed through a high-temperature solid-state reaction. The crystal structure was determined through Rietveld refinement, and a comprehensive analysis of the photoluminescence properties was conducted. When illuminated with light at either 396 or 552 nm, the SrZnAl 10 O 17 :Mn4+ phosphors displayed a distinct narrow emission band, covering the wavelength range of 600–800 nm, with a peak occurring at 692 nm. Notably, the photoluminescence intensity of these phosphors did not show significant variations under 396 and 552 nm light excitation—a relatively uncommon occurrence in Mn4+-doped red oxide phosphors. Furthermore, the photoluminescence spectra of SrZnAl 10 O 17 :Mn4+ phosphors closely matched the absorption spectra of PFR, suggesting the potential application of these phosphors in agricultural cultivation. [ABSTRACT FROM AUTHOR]

Photochromic materials have received increasing interest benefited by its promising application in anti-counterfeiting and erasable optical information storage with the rapid development of the information age. In this work, we have reported a perovskite configuration SrHfO 3 :Eu3+ photochromic powders, displaying the color changed from white to brown upon UV light irradiation, and it can be bleached by 365 nm light or heat treatment. Based on the energy transfer, the Eu3+ ions doped into SrHfO 3 host to obtain luminescence modulation attribute to the special excitation (302 and 396 nm) and emission (614 nm) properties, and the more efficient luminescence modulation is excited at 396 nm. The storage of verbal, images and digital signal can be realized by UV light irradiation, then the stored information can be read out through 254 nm light, and the recording information can be erased using 365 nm light illumination. In addition, the anti-counterfeiting application has achieved by employing alternating UV and 365 nm light illumination. Furthermore, the stored information undergoes several cycles with almost no degradation of "written in", "read out" and "erased", displaying excellent fatigue resistance and reversibility. These results suggest that the perovskite configuration SrHfO 3 :Eu3+ photochromic material has promising multi-functional application in optical information storage and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Nozzle materials always withstand ultra-high temperatures (above 2000 °C) in space propulsion and other fields, which results in complex physical-chemical phenomena under actual operating conditions. The ablation mechanism and microstructural evolution of W-3Re-xHfC alloys were investigated to simulate the actual service conditions. Results show an outstanding ablation resistance. The linear ablation rate of the W 3Re matrix is 6.67 μm/s, the W-3Re-0.5HfC, W-3Re-5HfC and W-3Re-10HfC alloys are 2.93 μm/s, 2.23 μm/s and 2.26 μm/s, respectively. The linear ablation rates of W-3Re-0.5HfC, W-3Re-5HfC, and W-3Re-10HfC alloys decreased by 66%, 67%, and 67% compared with the W 3Re matrix, respectively. Thermochemical oxidation of the W 3Re matrix and HfC was the primary ablation mechanism of W-3Re-xHfC alloys. This work contributes to the design and improving the ablation resistance of W Re alloy applications in extreme environments. • Adding HfC particles significantly improves the ablation properties of W- 3Re alloy. • The ablation distance is shortened or the ablation time is prolonged, the worse ablation resistance • HfC and HfO 2 particles have high melting points, which nail the matrix grains and improve improving ablation resistance. • Thermochemical oxidation of the W- 3Re matrix and HfC particles is the primary ablation mechanism. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fe3O4/GNS nanoparticles have the significantly enhanced dielectric properties when compared with pure Fe3O4. [•] The absorbing bandwidth of Fe3O4/GNS composites exhibits more wider than pure Fe3O4. [•] The peak value of the reflection loss of Fe3O4/GNS composites has a tendency to be more lower with a thinner thickness. [Copyright &y& Elsevier]

Mo 42Re alloy, as a high-temperature structural and functional material, has broad application prospects in the nuclear industry. In this study, the hot deformation behavior of Mo 42Re alloy was systematically investigated using hot compression tests and electron backscatter diffraction (EBSD) techniques in the temperature range of 1200–1500 °C and strain rate range of 0.001–1 s−1. The results showed that the flow stress of Mo 42Re alloy exhibited a strong dependence on temperature and strain rate. The strain rate sensitivity index (m -value) was high under the conditions of 1350–1450 °C and 0.001 s−1. With increasing deformation temperature and decreasing strain rate, dynamic recrystallization (DRX) was significantly promoted, and the recrystallized volume fraction increased from 2.79% at 1200 °C/1 s−1 to 20.3% at 1500 °C/0.001 s−1. Meanwhile, the occurrence of and DRX effectively reduced the grain reference orientation deviation (GROD) gradients and kernel average misorientation (KAM) levels within the grains. This study revealed the mechanisms of microstructural evolution during hot deformation of Mo 42Re alloy, providing important guidance for optimizing its thermomechanical processing parameters. • The Mo 42Re alloy exhibits pronounced strain-rate sensitivity at 1350 -1450 ℃ and 0.001 s -1 strain rate. • Elevating the deformation temperature and lowering the strain rate significantly enhance DRX fraction. • Raising temperature and lowering the strain rate promote DRV and DRX, reducing GROD gradients and KAM levels. [ABSTRACT FROM AUTHOR]

Optical Remote Sensing Small Satellite is for high-tech flight demonstration''s test and three dimensions mapping. Its system overview is presented in the paper, and it includes such items as mission objective and mission requirements, satellite system scheme, reliability, cost budget project schedule and management and operation. [Copyright &y& Elsevier]

In this study, TiO 2W addition improved the oxidation resistance of the Mo–Si–B composite at 1300 °C. The TiO 2 partially dissolved in SiO 2 modified the network structure of the SiO 2 glass and improved its fluidity at the initial oxidation stage. This favored to a continuous scale cover on the surface of the Mo–Si–B composite rapidly. The residual TiO 2W promoted the formation of a passivated multilayer borosilicate scale at current temperature, which could impede the MoO 3 volatilisation and O diffusion at the stable oxidation stage. The SiC W addition, compared to the TiO 2W , especially could ensure the Mo–Si–B–SiC composite withstand a higher temperature such as 1400 °C. Its oxidation and the more intermetallics in the composite could increase the number of active sites of the SiO 2 glass, thereby supplying the borosilicate scale with a relatively sufficient Si element. Thus, the transient oxidation stage was minimised and the initial mass loss was reduced, which indicated a continuous borosilicate scale had formed quickly at the initial stage. Finally, the improved viscosity of the borosilicate due to a lower B/Si ratio, could obviously decreased the oxygen diffusion and enabled the formation of a protective borosilicate layer at or above 1400 °C. [ABSTRACT FROM AUTHOR]

A novel strategy for a three-compartment module with selective polymer inclusion membranes (PIMs) was proposed for the simultaneous recovery of copper ions from two different feed solutions using 2-hydroxy-5-nonyl-benzaldoxime (M5640) as the carrier. The effects of the membrane composition and the concentration of sulfuric acid in the stripping solution on the transport of Cu(II) were evaluated. The simultaneous transport of Cu(II) through the PIMs was further performed from both copper–nickel–cobalt and copper–zinc solutions in a three-compartment module. The results showed that Cu(II) could be selectively transported into the stripping solution, whereas Ni(II), Co(II), and Zn(II) were left in the respective raffinates. Moreover, FT-IR, XPS and small-angle X-ray scattering (SAXS) analyses of the PIMs were performed to disclose the selective transport mechanism of Cu(II). To further verify the feasibility of the innovative application, the continuous enrichment transport and membrane stability were tested and compared with the performance of other liquid membrane systems. Owing to its high efficiency, selectivity, and good membrane stability, the three-compartment module can be potentially used for the removal and recovery of target metal ions from various leachates and industrial raffinates. • A three-compartment module with selective polymer inclusion membranes was proposed. • Simultaneous recovery of Cu(II) from two different feed solutions was achieved. • Cu(II) was selectively separated from two different feed solutions with M5640. • Transport mechanism of Cu(II) was disclosed by FI-IR, XPS, and SAXS analyses of PIMs. • The membrane module has high efficiency, selectivity and good stability. [ABSTRACT FROM AUTHOR]

A growing body of evidence suggests the deleterious effects of perfluoroalkyl substances (PFASs) on kidney, but little is known on the association between PFASs joint exposure and uric acid. Serum PFASs concentrations were measured in 661 participants recruited from Tianjin, China using liquid chromatography/mass spectrometry. The associations of single PFASs exposure with uric acid levels and hyperuricemia were assessed using multivariable linear and logistic regression models, respectively. Restricted cubic spline models were established to investigate the dose-response relationships between PFASs concentrations and uric acid levels. Bayesian Kernel Machine Regression (BKMR) model with a hierarchical variable selection was performed to assess the joint effect of PFASs on uric acid. Potassium perfluoro-1-octanesulfonate (PFOS) and perfluoro- n -octanoic acid (PFOA) were the dominated contributors with median concentrations of 16.80 ng/ml and 9.42 ng/ml, respectively. Increased PFOA concentration (per log 2 -unit) was associated with elevated uric acid level (β = 0.088, 95% CI: 0.033–0.143) and higher risk of hyperuricemia (OR = 1.134, 95% CI: 1.006–1.289). Conversely, the estimated change of uric acid associated with log 2 -unit increment in perfluoro- n -decanoic acid (PFDA) was −0.081 mg/dL (95% CI: -0.154, −0.009). A significant linear dose-response pattern was found between log 2 -transformed PFOA concentration and uric acid level. BKMR analyses indicated a non-significant overall effect of PFASs mixture on uric acid. Significant associations between PFOA and PFDA and uric acid, and between PFOA and hyperuricemia were found in the single-pollutant models, but the joint effect of PFASs mixture on uric acid was not observed in the BKMR model, which provided new insights in regulation policies and risk assessment of PFASs. [Display omitted] • PFOA was positively associated with uric acid level and hyperuricemia. • A linear dose-response relationship of PFOA with uric acid was found. • A negative association of PFDA concentrations and uric acid level was observed. [ABSTRACT FROM AUTHOR]

Dendrobium mixture (DM) is a patent Chinese herbal formulation consisting of Dendrobii Caulis, Astragali Radix, Rehmanniae Radix as the main ingredients. DM has been shown to alleviate diabetic related symptoms attributed to its anti-hyperglycaemic and anti-inflammatory activities. However, the effect on diabetic induced cognitive dysfunction has not been investigated. This study aims to investigate the effect of DM in improving diabetic cognitive impairment and associated mechanisms. Our study confirmed the anti-hyperglycaemic effect of DM and showed its capacity to restore the cognitive and memory function in high fat/high glucose and streptozotocin-induced diabetic rats. The neuroprotective effect was manifested as improved learning and memory behaviours, restored blood-brain barrier tight junction, and enhanced expressions of neuronal survival related biomarkers. DM protected the colon tight junction, and effectively lowered the circulated proinflammatory mediators including tumour necrosis factor-α, interleukin-6 and lipopolysaccharides. In the gut microbiota, DM corrected the increase in the abundance of Firmicutes , the increase in the ratio of Firmicutes / Bacteroidetes , and the decrease in the abundance of Bacteroidetes in diabetic rats. It also reversed the abundance of Lactobacillus , Ruminococcus and Allobaculum genera. Short chain fatty acids, isobutyric acid and ethylmethylacetic acid, were negatively and significantly correlated to Ruminococcus and Allobaculum. Isovaleric acid was positively and significantly correlated with Lactobacillus , which all contributing to the improvement in glucose level, systemic inflammation and cognitive function in diabetic rats. Our results demonstrated the potential of DM as a promising therapeutic agent in treating diabetic cognitive impairment and the underlying mechanism may be associated with regulating gut microbiota. [Display omitted] • Dendrobium mixture (DM) restored diabetic-induced cognitive and memory function in diabetic rats. • DM protected colon epithelial tight junction and reduced the systemic inflammation. • DM corrected disordered abundances of Firmicutes and Bacteroidetes. • DM protected colon epithelial tight junction and reduced the systemic inflammation. • Isobutyric acid and ethylmethylacetic acid were negatively related to DM effective genera Ruminococcus and Allobaculum. • Restored isovaleric acid was positively correlated to increased abundance of genus Lactobacillus. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fe x O y @SiO2 nanoparticles were kept well-defined in size and shape as Fe3O4@SiO2. [•] Fe x O y @SiO2 exhibit enhanced magnetic properties (Ms =76.032emu/g). [•] Fe x O y @SiO2 exhibit enhanced microwave absorption properties (RL=−23dB). [Copyright &y& Elsevier]

The hot compression behavior of sintered W-3Re-5HfC alloy was investigated using the Gleeble1500D thermo-mechanical simulator at deformation temperatures and strain rates from 1200 °C to 1500 °C and 0.001 s−1 to 1 s−1, respectively. The microstructural evolution and flow behavior were studied. The microstructural observations reveal that the original grains are initially squashed, and then refined, which can be attributed to the occurrence of dynamic recovery and continuous dynamic recrystallization. Moreover, the electron backscattered diffraction analysis demonstrates a typical fibrous texture at low temperatures and high strain rates, which gradually transforms into the plate-like texture with the increase of temperature and decrease of strain rate. Based on the experimental results, arrhenius constitutive equations and an artificial neural network (ANN) model were developed for the characterization and prediction of the high-temperature deformation behavior in the W-3Re-5HfC alloy. The results indicate that the ANN model is more efficient in predicting the hot compressive behavior of W-3Re-5HfC alloy than the constitutive equations. The correlation coefficient and average absolute relative error in constitutive equations are found to be 0.99299 and 4.09%, respectively, whereas the corresponding values in the ANN model are found to be 0.99892 and 0.99%. In order to meet the performance requirements of different high-temperature structure parts, thermal deformation of W-3Re-5HfC alloy is needed to obtain the required microstructure and mechanical properties. ANN model provide theoretical basis for reducing deformation defects, saving process design time and obtaining machining parts with excellent microstructure. • The hot deformation behavior be predicted by Arrhenius model and artificial neural network model. • Dynamic evolution of coarse grains can be controlled by DRV and DRX. • A typical fibrous texture at low temperature and high strain rate • Artificial neural network model has higher accuracy in predicting the hot deformation behavior. [ABSTRACT FROM AUTHOR]