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Gaussian vibration signal generated by the current shaking table according to power spectral density (PSD) in international standards was widely used for packaging random vibration test in laboratory. However, the actual road vehicle vibration is non-Gaussian. The key limitation is that the simulated Gaussian vibration cannot reconstruct the shock events buried in the vibration, which may result in inaccurate reliability evaluation of cushion packaging. A new simulation technique called shock extraction method has been proposed and demonstrated in our earlier study. This article is a further study of our previous research. The shock extraction method was compared with other three representative methods including the single level PSD, three way split spectral and wavelet decomposition in terms of simulation effect. The results revealed that the signal simulated by the shock extraction method was closest to the original signal, which possessed the same vibration intensity, duration, approximate statistical characteristics and PSD plots with the original signal. The simulation effect of the shock extraction method was the best, and the worst was the single level PSD. The wavelet decomposition and three way split spectral were somewhere in the middle.

Background The microRNA, miR-139-5p, plays an important role in the initiation and progression of various tumor types including osteosarcoma (OS). Objective This study aimed to detect the serum miR-139-5p expression in OS and analyze its association with clinical variables. Methods Blood samples were taken from 98 OS patients and 50 healthy individuals, and serum miR-139-5p levels were measured by quantitative reverse transcription-polymerase chain reaction. Results We found the expression of serum miR-139-5p in OS patients was significantly lower than that in healthy individuals, and miR-139-5p levels were dramatically decreased in patients with distant metastasis or in higher clinical stage. Receiver-operating characteristic (ROC) analysis revealed that serum miR-139-5p could well discriminate OS patients from healthy controls with a high sensitivity and specificity. Moreover, low serum miR-139-5p expression was strongly associated with distant metastasis, tumor stage and shorter overall survival. Both univariate and multivariate analyses showed that serum miR-139-5p level could serve as an independent prognostic marker for OS. Conclusions Taken together, data from this study demonstrates that serum miR-139-5p could be used as a tumor biomarker for OS diagnosis and prognosis.

This paper presents two mathematical models to predict the initial peak stress and the plateau stress of five-layered and seven-layered corrugated paperboards respectively, which are simplified and regarded as the orthotropic panels under longitudinal compression. The resultant stress-strain curve exhibits an initial stiffening stage with the initial peak stress determining the edgewise crush resistance of paperboard, and a long plateau stage with which most impact energy can be absorbed. By analyzing the elastic buckling of board walls, the model for prediction of the initial peak stress is obtained, while the plateau stress model is developed based on the gradual process of compression and energy conservation principle. And then, experiments are conducted to validate the presented models by comparing the predicted values with those by experiments, showing overall good agreement. It can be concluded that the proposed models are suitable for design of multi-layered corrugated box and cushioning packaging.

The components of the flux are optimized and the environmental friendly flux withexcellent comprehensive performance is prepared. Then the composition of the solder paste isoptimized to prepare the SMT environmental protection and high efficient lead-free solder paste, andits performance is studied. The results show that the storage stability, printability, weldability andenvironmental protection of the SMT environmental protection and high efficient lead-free solderpaste are good, and the reliability is high. The related technical indexes have reached or superior tothe commercial solder paste, and have reached the commercial level initially.

Background To analyze the impact of spino cranial angle (SCA) on alteration of cervical alignment after multi-level anterior cervical discectomy fusion (ACDF) and explore the relationship between SCA and health-related quality of life (HRQOL) scores. Material and methods In total, 49 patients following multi-level ACDF for multi-level cervical spondylotic myelopathy (MCSM) with more than 2 years follow-up period were enrolled. Radiographic data including SCA were measured. Receiver operating characteristics (ROC) curve analysis was applied to confirm the optimal cut-off values of SCA for predicting sagittal balance. Patients were divided into two groups on the basis of the cut-off value of preoperative SCA. Correlation coefficients were analyzed between SCA and HRQOL scores. Results Optimal cut-off values for predicting sagittal balance was SCA of 88.6°. Patients with higher SCA, no matter preoperatively, postoperatively and at follow-up, got lower T1-Slope (T1s), C2–C7 lordosis angle (CA) and higher △SCA (pre vs post: p = 0.036, pre vs F/U: p = 0.022). Simultaneously, pre-SCA, post-SCA, and F/U-SCA in the high SCA group were positively correlated with the pre-NDI, post-NDI, and F/U-NDI scores respectively (pre: p < 0.001, post: p = 0.015, F/U: p = 0.003). However, no correlation was performed in the low SCA group. Conclusion An excessive SCA can be considered to cause poorer clinical outcomes at preoperative and better correction after surgery. The SCA could be used as a new reference value to determine sagittal balance parameters of the cervical spine and to assess the quality of life.

The purpose of our study was to analyze and compare the spino cranial angle (SCA) in patients with degenerative cervical spondylolisthesis (DCS) and asymptomatic controls and to determine whether SCA could help diagnose DCS.We enrolled 50 patients diagnosed with DCS (4.3%) from among 1168 patients and the same number of asymptomatic participants as the control group by using cervical radiographs. Both groups underwent cervical radiographs and computed tomography at the same time. Various sagittal parameters were measured on computed tomography in a standardized supine position and compared with the asymptomatic control group. The Spearman correlation coefficient was applied to test the correlation among the sagittal parameters in the DCS group. Multivariate logistic regression analysis and receiver operating characteristic curve analysis were performed to determine whether SCA could help predict DCS.Fifty patients were enrolled in the DCS group, and 50 asymptomatic participants were included in the control group. The SCA was significantly lower for the DCS group than for the control group (76.84 ± 7.48 degrees vs. 82.47 ± 8.06 degrees, P0.001), and the T1 slope (T1s) was significantly greater for the DCS group than for the control group (27.29 ± 7.84 degrees vs. 22.28 ± 6.43 degrees, P = 0.001). Except for SCA and T1s, no other parameters showed significant differences. The SCA on the computed tomography scan was significantly correlated with the values of the T1s (r = -0.890, P0.001), cervical lordosis (r = -0.437, P = 0.002), C2-C7 sagittal vertical axis (r = 0.397, P = 0.004), and thoracic inlet angle (r = -0.565, P0.001). Multivariate logistic regression analysis and receiver operating characteristic curve analysis showed that both a lower SCA and a higher T1s could be risk factors for DCS, and an SCA of79.1 degrees demonstrated significant diagnostic value for the detection of DCS.Patients in the DCS group had a lower SCA and a higher T1s. Both a lower SCA and a higher T1s could be risk factors for DCS, and an SCA of79.1 degrees demonstrated significant diagnostic value for the detection of DCS.

Objective To investigate the correlation between CT texture analysis and synchronous distant metastasis in patients with lymph node-negative colorectal cancer. Methods The preoperative CT images of 82 patients with lymph node-negative colorectal cancer were analyzed retrospectively.There were 12 patients with simultaneous distant metastasis and 70 patients without simultaneous distant metastasis.The maximum plane of the lesion on plain scan and portal CT images was analyzed by TexRAD software.When the spatial scaling factor(SSF)was 0 and 2-6,six texture parameters were obtained,and the differences of texture parameters between the two groups were compared.The counting data were analyzed by chi-square test and the measurement data by Mann-Whitney test. Results There was a significant difference in the skewness of SSF=3 between the simultaneous distant metastasis group and the non-synchronous metastasis group on plain CT scan(

Field application of numerical simulation to assist injection and production deployment has a long history of fitting cycle, heavy workload and low efficiency. It is necessary to improve the history matching method, improve the efficiency and precision, and ensure the timeliness and implementation effect of injection and production deployment plan. In this paper, the ZhongQu, Haiyang oil production plant, is taken as the application block. Based on the existing mathematical model and optimization algorithm, the rationality and adaptability of fitting parameters are analyzed and studied. Compile the automatic history matching software, combine with the long experience of the block, judge and analyze the fitting effect, and ensure that the automatic history matching process is reasonable and effective. Combined with the existing post-processing software of injection and production allocation results, the calculation of block stratification indexes are realized, and the mathematical model result data are converted into forms to realize the efficient stratifications and fine injection and production allocation and the scheme prediction and optimization. The automatic history matching software was applied, and the matching result was accelerated by 2–5 times. Combined with the post-processing software, the effect of injection and production in ZhongQu of guantao formation was remarkable. From January to December 2019, ZhongQu of guantao formation water injection rate was adjusted to 242 Wells, among which 202 Wells were dynamically allocated, the injection-production ratio was increased to 32 Wells and decreased to 8 Wells. The overall daily injection volume was changed to 7175 m3. The production of corresponding wells added 28,343 tons. The promotion and application of the software has reduced the history matching workload of engineers and improved the efficiency of injection-production allocation. It has formed a series of technology which include numerical-simulation-aided layered and fine injection-production deployment technology which include automatic history matching technology, reservoir numerical simulation and mathematical model result post-processing software. The series of technology provides data and technical support for building intelligent oilfield.

Five 3-formyl-2-arylbenzofuran derivatives, including three new compounds (

We construct the gravitating mass of an isolated composite system on asymptotically-flat spacetimes within conventional general relativity and investigate when this quantity is well defined. For stationary spacetimes, this quantity is known to exactly equal the physical (ADM) mass. However, it remains an open question whether these two masses are equal in the absence of a timelike Killing vector. This is especially apropos since our universe has an `origin' and hence no such Killing vector. Further, if these masses failed to agree then composite systems could behave as if they had a `dark component,' whose gravitating mass would not equal the physical mass-energy present. The existence of such an apparent discrepancy is indeed ubiquitous in galaxies and galaxy clusters, though currently it is attributed to the presence of dark matter. We conclude that the theoretical question of the relation between these masses for dynamical spacetimes is ripe for attention., 8 pages, 1 figure

Accelerated random vibration test is now the important dynamic performance and safety evaluation technique for transport packaging system during transportation. The current widely used time scale of accelerated random vibration test in engineering test and some standards is “Inverse power law,” which is based on Basquin (power function) fatigue damage model and [Formula: see text] curve, but is not completely suitable for transport packaging system. In author’s previous research, the general theory of accelerated random vibration test based on acceleration PSD and [Formula: see text] curve was developed which is applied for any fatigue damage model besides Basquin type. The study in this paper is the further and extensive research of previous research. The definite expression between response von Mises equivalent stress ([Formula: see text]) of the products and tri-axial acceleration Root-Mean-Square (RMS) was developed, based on which [Formula: see text] curve was transformed to [Formula: see text] curve to describe the product damage. Time scale of accelerated random vibration was obtained. The proposed method was verified by finite element analysis. In addition, the effects of excitation spectrum shape and system damping on the response vibration of products were discussed. This study is valuable in engineering for safety assessment and random vibration analysis of transport packaging system.

Anti-angiogenic drugs (AADs) are currently the main choice for systemic treatment of hepatocellular carcinoma, but treatment-related proteinuria can affect the routine use of AADs, which in turn affects the overall efficacy, its prevention is a clinical aspiration. At present, most clinicians give angiotensin-converting enzyme inhibitors (ACEIs) to alleviate proteinuria according to diabetic nephropathy guidelines or expert recommendations. However, its efficacy and whether it promotes cancer are controversial. Our clinical work has found that the use of ACEIs has not effectively relieved proteinuria, and some cases even have obvious tumor progression. Here we confirmed that in different tumor-bearing mouse models, ACEIs not only did not delay the appearance of proteinuria or reduce the degree of proteinuria caused by AADs, but also reduced the anti-cancer efficacy of AADs, and the reduction of anticancer efficacy has nothing to do with the change of VEGF signaling pathway, Our study show the combination of ACEIs and AADs aggravates the production of kidney-derived erythropoietin(EPO). In turn, EPO compromises the anti-angiogenic effects of AADs and decreases antitumor activity. This study presents treatment of proteinuria caused by AADs with ACEIs is useless and plays a role in drug resistance. Our purpose is to contribute to the rational management of side effects of AADs and to develop relevant guidelines.

Comprehensive bridge design should consider simultaneous actions of wind and temperature. The current load combination method of directly superposing extreme wind and temperature actions i...

Objective To study the anti-hypertrophic scar effect of the six-herb Chinese medicine composition (SCMC) ointment on the rabbit ear hypertrophic scar models. Methods The optimal formulation of SCMC ointment matrix was screened by the orthogonal designs and a series of evaluation tests. The SCMC ointment was prepared through emulsifying method. The rabbit ear hypertrophic scar models were established and used to investigate the anti-hypertrophic scar effect of SCMC ointment. Results Our results demonstrated that all the quality control indications of the SCMC ointment met the requirements. Anti-hypertrophic scar activity results showed that all the rabbit ear scar tissues appeared different degrees of shrink and fading, and took an unobvious but palpable shift from hard to soft texture with the low, middle and high concentration SCMC ointments treatments in vivo. Additionally, on 21st day the scar area and thickness in different concentrations of SCMC ointment groups were significantly reduced than control group, in a concentration-dependent manner. The immunohistochemical results also indicated that the SCMC ointment had good anti-hypertrophic scar properties and could inhibit hypertrophic scar formation. Conclusion The SCMC ointment could improve the blood circulation condition of hypertrophic scar tissues. Our research has demonstrated the Chinese medicine composition ointment with good anti-hypertrophic scar properties that could be used to treat hypertrophic scars. Meanwhile, it provides a theoretical basis for further clinical application.

The limited availability of nitrogen (N) is a fundamental challenge for many crop plants. We have hypothesized that the relative crop photosynthetic rate (P) is exponentially constrained by certain plant-specific enzyme activities, such as ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), NADP-glyceraldehyde-3-phosphate dehydrogenase (NADP-G3PDH), 3-phosphoglyceric acid (PGA) kinase, and chloroplast fructose-1,6-bisphosphatase (cpFBPase), in Triticum aestivum and Oryza sativa. We conducted a literature search to compile information from previous studies on C3 and C4 crop plants, to examine the photosynthetic rate responses to limited leaf [N] levels. We found that in Zea mays, NADP-malic enzyme (NADP-ME), PEP carboxykinase (PCK), and Rubisco activities were positively correlated with P. A positive correlation was also observed between both phosphoenolpyruvate carboxylase (PEPC) and Rubisco activity with leaf [N] in Sorghum bicolor. Key enzyme activities responded differently to P in C3 and C4 plants, suggesting that other factors, such as leaf [N] and the stage of leaf growth, also limited specific enzyme activities. The relationships followed the best fitting exponential relationships between key enzymes and the P rate in both C3 and C4 plants. It was found that C4 species absorbed less leaf [N] but had higher [N] assimilation rates (A rate) and higher maximum photosynthesis rates (Pmax ), i.e., they were able to utilize and invest more [N] to sustain higher carbon gains. All C3 species studied herein had higher [N] storage (Nstore) and higher absorption of [N], when compared with the C4 species. Nstore was the main [N] source used for maintaining photosynthetic capacity and leaf expansion. Of the nine C3 species assessed, rice had the greatest Pmax , thereby absorbing more leaf [N]. Elevated CO2 (eCO2) was also found to reduce the leaf [N] and Pmax in rice but enhanced the leaf [N] and N use efficiency of photosynthesis in maize. We concluded that eCO2 affects [N] allocation, which directly or indirectly affects Pmax . These results highlight the need to further study these physiological and biochemical processes, to better predict how crops will respond to eCO2 concentrations and limited [N].

A reasonable prediction of infectious diseases transmission process under different disease control strategies is an important reference point for policy makers. Here we established a dynamic transmission model via Python and realized comprehensive regulation of disease control measures. We classified government interventions into three categories and introduced three parameters as descriptions for the key points in disease control, these being intraregional growth rate, interregional communication rate, and detection rate of infectors. Our simulation predicts the infection by COVID-19 in the UK would be out of control in 73 days without any interventions; at the same time, herd immunity acquisition will begin from the epicentre. After we introduced government interventions, single intervention is effective in disease control but at huge expense while combined interventions would be more efficient, among which, enhancing detection number is crucial in control strategy of COVID-19. In addition, we calculated requirements for the most effective vaccination strategy based on infection number in real situation. Our model was programmed with iterative algorithms, and visualized via cellular automata, it can be applied to similar epidemics in other regions if the basic parameters are inputted, and is able to synthetically mimick the effect of multiple factors in infectious disease control., Comment: Errors appears in Results, data changed

Five 3-formyl-2-arylbenzofuran derivatives, including three new compounds (1-3) and two known analogues (4-5), were identified from the 95% EtOH extract of Itea yunnanensis. Extensive spectroscopic analyses were performed for the structure elucidation of all new benzofurans, and single-crystal X-ray diffraction analyses were further employed for the structure verification of iteafuranals C (1) and D (2). In MTT assay, iteafuranal E (3) and iteafuranal A (4) displayed significant growth inhibition effect on SK-Hep-1 cells with IC50 values of 5.365 μM and 6.013 μM, respectively. The colony formation assay of 3 and 4 further confirmed their remarkable inhibitory effect on cell growth. Preliminary mechanism study demonstrated that 3 remarkably down-regulated the phosphorylation level of ERK, which suggested 3 could inhibit cell growth and induce apoptosis of SK-Hep-1 cells by blocking RAS/RAF/MEK/ERK signaling pathway. This study highlighted the potential of 3-fomyl-2-benzofuran derivatives as novel lead compounds to treat Hepatocellular carcinoma.

Polyanion-type phosphate materials are highly promising cathode candidates for next-generation batteries due to their excellent structural stability during cycling; however, their poor conductivity has impeded their development. Isostructural and multivalent anion substitution combined with carbon coating is proposed to greatly improve the electrochemical properties of phosphate cathode in sodium-ion batteries (SIBs). Specifically, multivalent tetrahedral SiO44- substitute for PO43- in Na3 V2 (PO4 )3 (NVP) lattice, preparing the optimal Na3.1 V2 (PO4 )2.9 (SiO4 )0.1 with high-rate capability (delivering a high capacity of 82.5 mAh g-1 even at 20 C) and outstanding cyclic stability (≈98% capacity retention after 500 cycles at 1 C). Theoretical calculation and experimental analyses reveal that the anion-substituted Na3.1 V2 (PO4 )2.9 (SiO4 )0.1 reduces the bandgap of NVP lattice and enhanced its structural stability, Na+ -diffusion kinetics and electronic conductivity. This strategy of multivalent and isostructural anion substitution chemistry provides a new insight to develop advanced phosphate cathodes.

The intrinsic charge-transfer property bears the primary responsibility for the sluggish redox kinetics of the common electrode materials, especially operated at low temperatures. Herein, we report the crafting of homogeneously confined Fe

Background Cervical sagittal parameters were closely related with clinical outcomes after multi-level ACDF. Our purpose was to evaluate the clinical outcomes and cervical sagittal parameters in patients with MCSM after ACDF and to identify the risk factors of poor clinical outcomes. Material and methods ACDF was performed in 89 patients with MCSM. Based on average JOA recovery rate, patients were divided good-outcome group (group GO) and poor-outcome group (group PO). The cervical sagittal parameters including Cobb angle, SVA, T1S, cranial tilt and cervical tilt were measured. Multivariate logistic regression was used to identify risk factors. Results Fifty-four patients (60.67%) were divided into group GO, while 35 patients (39.33%) were divided into group PO. Cobb angle, SVA and T1S was corrected from preoperative average 11.80° ± 9.63°, 23.69 mm ± 11.69 mm and 24.43° ± 11.78° to postoperative average 15.08° ± 9.05°, 18.79 mm ± 10.78 mm and 26.92° ± 11.94° respectively (p p = 0.008) and △SVA (p = 0.009) showed significantly statistical differences between two groups. Longer symptom duration, lower preoperative JOA score, smaller △Cobb angle and larger △SVA were identified as risk factors of poor clinical outcomes. Conclusion Multi-level ACDF is an effective surgical method to treat patients with MCSM. However, long duration of preoperative symptoms, lower preoperative JOA score, smaller △Cobb angle and larger △SVA are risk factors for poor outcomes in patients with MCSM after ACDF. Sagittal parameters should be paid attention to in surgery.

The homotopy perturbation method with an auxiliary term is applied to obtain an approximate analytical solution for the tangent nonlinear packaging system. To further raise the accuracy of the solution, this work has expanded the possibility of the energy method for the homotopy perturbation method with an auxiliary term. And then, the amplitude and frequency of the tangent nonlinear packaging system can be calculated. The results show that the solution is in good consistent with the numerical solution solved by the Runge–Kutta method. It can be concluded that the proposed method is suitable for the optimal design of a tangent nonlinear packaging system.

Some Epichloe species are beneficial to their plant hosts by improving fitness and resistance to stress. The natural, seedborne, asymptomatic symbiotic endophyte Epichloe sinica is specific for Roegneria spp., which are perennial grasses found in grasslands or meadows; many species of Roegneria are excellent forage plants. This study was designed to reveal the biological function of E. sinica via seedling assays with drought simulation using polyethylene glycol (PEG)-6000. Endophyte infected (EI) and endophyte free (EF) R. kamoji seeds (obtained by heat treatment) were germinated and grown on 0, 10, 15 and 20% PEG-6000 for 10 days; seedling and root system morphologies were investigated, and reactive oxygen species (ROS), which act as signaling molecules in plant responses to abiotic stress, were detected. E. sinica enhanced both the germination potential and rate of R. kamoji seeds treated with high concentrations of PEG-6000. After PEG treatment, shoot and root morphologies differed significantly between EF and EI seedlings. Additionally, lower amounts of ROS concentration were detected in the leaves of EI seedlings treated with high concentrations of PEG-6000. In conclusion, E. sinica promoted PEG-6000 simulated drought stress resistance in R. kamoji seedlings.

It has been hypothesized that geological and climatic changes in the Sino–Himalayan region played a significant role in evolutionary history. In this study, we tested this hypothesis by investigating the phylogeography of Excoecaria acerifolia (Euphorbiaceae), a riparian plant species that is widely distributed in the hot/warm-dry river valleys of the Sino–Himalayan region. Spatial analysis of molecular variance, a median-joining network and a Bayesian phylogenetic tree based on plastid DNA, all suggested three major lineages corresponding to the Jialing-Min-Dadu (JMD lineage), Jinsha-Yalong-Salween (JY lineage) and Yarlung Tsangpo-Mekong-Red-Nanpan (YMRN lineage) drainage basins. This was also generally supported by the results based on nuclear DNA. The divergence times of these three major lineages based on both datasets fell in the early Pleistocene, coinciding with the period of drainage reorganization events in the Sino–Himalayan region. The diversification times in the lineages were, however, dated back to the mid Pleistocene, corresponding to the Naynayxungla glaciation (0.72–0.50 Mya) and the penultimate glaciation (0.30–0.13 Mya), which were the most and second most severe glaciations in this region, respectively. Furthermore, mismatch analyses, neutrality test and ecological niche modelling suggest long-term demographic stability of the JY and JMD populations, with expansion only in the YMRN populations during the period(s) from the late penultimate glaciation (138.12 Kya) to the Last Interglacial (95.79 Kya), probably because of less extensive glaciations since the late Pleistocene and the gradually warming interglacial stage. Our study provides one of the few pieces of evidence indicating that combined historical drainage reorganization and climatic change since the Pleistocene might also have acted as important factors in the evolutionary history of riparian plants in the region.

Since asymmetric contact is characteristic of the package surface, jumping phenomenon may happen under strong random vibration. To study the influence of jumping phenomenon on package response, a piecewise linear random vibration model is established. By applying Fokker-Planck-Kolmogorov (FPK) equation method, distribution of displacement composed of Gaussian distribution and exponential distribution is obtained. After that, distribution of maxima of displacement composed of Rayleigh distribution and exponential distribution is obtained. The proportion of time taken by loss of contact in a single cycle is studied under different peak of displacements. When the peak of displacement is from 1 to 3, the period is from 2 to 2.56, and proportion of time taken by loss of contact is from 0 to near 50%. By applying the relation between peak of displacement and contact force, distribution of maxima of contact force can be obtained as translational Rayleigh distribution, which is also proved by numerical simulation and experiment respectively. Moreover, by numerical simulation, distribution of acceleration and time history of modified displacement are obtained. It is found that when RMS value of displacement signal increases, probability of loss of contact becomes greater, and the time cost by the same number of cycles will be prolonged. By experiment, distribution of acceleration and acceleration PSD are obtained. It is found that when random excitation increases, the probability of –g increases and the frequency corresponding to peak of acceleration PSD declines. It indicates that the loss of contact causes the decline of the central frequency.

Migration of chemical additives from polypropylene material to food simulants (50% ethanol solution and isooctane) at the temperature of 293, 313 and 343 K are investigated by using molecular dynamics (MD) simulation technique based on the classical mechanics. A two-phase MD model is firstly established to simulate the migration dynamic process. The migration dynamic details are obtained, especially for the significant kinetic parameter of diffusion coefficient. The accuracy of MD simulation is assessed by comparing the diffusion coefficients obtained by MD simulations, experiments and Piringer model. It is indicated that the diffusion coefficients of additives obtained from two-phase MD model are generally within one order of magnitude of the corresponding experiments. The two-phase MD model of polypropylene – food simulant offers fairly good predictive ability, which means MD simulation technique is a powerful way to predict the migration process and level of additives from polypropylene material to food. In addition, different influencing factors for additive migration are examined including the additive molecular structure, interaction energy between additive molecule and polypropylene, food simulant and temperature. The movement trajectories of additives in polypropylene – food simulant cells at different simulation time suggest that the additive molecules vibrate rather than hopping for a long time, until they find the equal or larger transport channel to diffuse.

Temperature-induced variations of elastic moduli in solid media are generally characterized by a strong nonlinear dependence on temperature associated with complex deformations under thermal treatments. Conventional thermoelasticity with third-order elastic constants for the one-order temperature dependence has been extensively studied for crystals, but encountering problems of divergent and limited velocity variations for rocks as a polycrystal mixture, especially at high temperatures. The extension of the theory beyond high-order elastic constants to solid media is addressed in this article to describe the nonlinear temperature dependence of both elastic constants and wave velocities. The total strain is divided into the background component associated with temperature variations and the infinitesimal component induced by propagating waves. A third-order temperature dependence of velocity variations is formulated by taking into account fourth-order elastic constants. Applications to solid rocks (sandstone, granite, and olivine) demonstrate an accurate description of temperature-induced variations, especially for high temperatures. Unlike crystals, the synthetic averaging elastic constants for a solid rock (as a polycrystal mixture) change less than 10% with temperatures. The thermal sensitivity of P-wave velocities is much more than that of S-wave velocities over the vast majority of temperatures examined.

The effects of heat treatment and strontium (Sr) addition on the microstructure and mechanical properties of ADC12 alloys were investigated, and two-stage solution treatment was introduced. The results indicated that the addition of Sr obviously refined the microstructure of ADC12 alloys. When 0.05 wt% Sr was added into the alloy, the eutectic Si phase was fully modified into fine fibrous structure; α-Al and β-Al5FeSi phases were best refined; and the eutectic Al2Cu phase was modified into block-like Al2Cu phase that continuously distributed at the grain boundary. The ultimate tensile strength (UTS) (270.63 MPa) and elongation (3.19%) were increased by 51.2% and 73.4% respectively compared with unmodified alloys. After the two-stage solution treatment (500 °C, 6 h+520 °C, 4 h), for 0.05 wt% Sr modified ADC12 alloys, the Si phases transformed into fine particle structure and Al2Cu phases were fully dissolved. The peak hardness value of the alloys processed by the two-stage solution treatment was increased by 8.3% and 6.8% respectively compared to solution treatment at 500 °C and 520 °C. After the aging treatment (175 °C, 7 h), the hardness and UTS were increased by 38.73% and 13.96% respectively when compared with the unmodified alloy.

The structures, semiconductor and photocurrent response properties of three 1,4-diazabicyclo[2.2.2]octane derivative-templated iodobismuthates, (Et2DABCO)3(BiI6)2 (1), (i-Pr2DABCO)2(Bi2I10) (2), [(Me2DABCO)2(Bi2I10)2] n (3) (Et2DABCO2+ = N,N′-diethyl-1,4-diazabicyclo[2.2.2] octane, i-Pr2DABCO2+ = N,N′-diisoproyl-1,4-diazabicyclo[2.2.2] octane, Me2DABCO2+ = N,N′-dimethyl-1,4-diazabicyclo[2.2.2] octane), are reported. Based on the templates with different substitutents on 1,4-diazabicyclo[2.2.2]octane, mono-nuclear ((BiI6) 3 − for 1), dimer ((Bi2I10) 4 − for 2) and 1-D chain ((BiI5) 2n− for 3) can be obtained. C-H···I hydrogen bonds contribute to the structural extension to 2-D layer (for 2) and 3-D network (for 3). Their absorption spectra were investigated, and energy band gaps of 2.24/1.73/1.44 eV indicate their narrow-gap semiconductor natures. Their photocurrent response properties were also discussed. Finally, theoretical calculation was executed to give structure-properties correlation.

This paper presents new zircon U–Pb ages and Hf isotopic data, and whole–rock geochemical data for Late Devonian–Carboniferous igneous rocks from the Songnen–Zhangguangcai Range Massif (SRM), NE China, to constrain the late Paleozoic tectonic evolution of the eastern Central Asian Orogenic Belt and the nature of the crust beneath the SRM. LA–ICP–MS zircon U–Pb dating reveals two stages of magmatism in the Late Devonian (366 Ma) and Carboniferous (325–313 Ma). The Late Devonian magmatic event produced alkali feldspar granites with high SiO2 and total alkali contents, as well as pronounced negative Eu anomalies, similar to A-type granites. Based on these features, their high zircon eHf(t) values (+9.6 to +13.0), and the early Paleozoic tectonic evolution of the eastern SRM, we conclude that the primary magma for the Late Devonian granites was generated by partial melting of juvenile lower crust in a post-collisional extensional environment. The Carboniferous magmatic event produced a suite of intermediate–felsic igneous rocks. The intermediate rocks, including basaltic andesite, andesite, and quartz monzodiorites, have low SiO2 contents, high Mg#, high Cr, Co, and Ni contents, and display arc-like trace element characteristics. Based on these observations and their high zircon eHf(t) values (+5.8 to +10.7), we suggest their primary magma was derived from partial melting of depleted mantle, metasomatized by subduction-related fluids. The felsic rhyolites and monzogranites have high SiO2 contents, low Mg#, extremely low Cr, Co, and Ni contents, and zircon eHf(t) values of +10.5 to +13.7 and +4.2 to +6.9, respectively. These results indicate that the primary magma for the felsic rocks was derived from partial melting of heterogeneous juvenile crust. The Carboniferous igneous rock assemblages, together with coeval carbonate sedimentary formations, record an intra-plate extensional setting. The zircon eHf(t) data of Paleozoic igneous rocks from the eastern SRM define a temporal trend that is consistent with tectonic evolution. The increase in eHf(t) values during the early late Paleozoic age mirrors changes in magma source, corresponding to a switch from subduction–collision to post-collision tectonic regimes in the SRM. The zircon Hf isotopic compositions of the studied Late Devonian–Carboniferous igneous rocks record crustal accretion in the eastern SRM during the Neoproterozoic–early Paleozoic. Reworking of these crustal materials occurred in a post-collisional extensional environment during the late Paleozoic.

A phytochemical study on the rhizomes of Gastrodia elata f. glauca resulted in the isolation of three new parishin derivatives and one new adenosine derivative, together with six known compounds. Their structures were elucidated mainly by spectroscopic analysis and compared to published data. All these isolates were evaluated for their neuroprotective effects against 6-hydroxydopamine-induced cell death, and new compound 4 showed potent activity with an EC50 value of 12.0 μM.

A series of random terpolymers P2−P5 were designed and synthesized by randomly embedding 5 mol%, 10 mol%, 15 mol% and 25 mol% feed ratios of low cost 2,2-bithiophene as the third monomer to the famous donor-acceptor (D-A) type copolymer PTB7-Th (P1). All polymers showed similar molecular weight with number-average molecular weight (Mn) and weight-average molecular weight (Mw) in the range of (59−74) and (93−114) kg·mol−1, respectively, to ensure a fair comparison on the structure-property relationships. Compared with the control copolymer PTB7-Th, the random terpolymers exhibited enhanced absorption intensity in a wide range from 400 nm to 650 nm in both solution and film as well as in polymer/PC71BM blends. From grazing incident wide-angle X-ray diffraction (GIWAXS), compared with the regularly alternated copolymer PTB7-Th, the random terpolymers demonstrated mild structural disorder with reduced (100) lamellar stacking and slightly weakened (010) π-π stacking for the polymers as well as slightly reduced PC71BM aggregation in polymer/PC71BM blends. However, the measured hole mobility for terpolymers ((1.20−3.73) × 10−4 cm2·V−1·s−1) was evaluated to be comparable or even higher than 1.35 × 10−4 cm2·V−1·s−1 of the alternative copolymer. Enhanced average power conversion efficiency (PCE) from 7.35% to 8.11% and 7.79% to 8.37% was observed in both conventional and inverted device architectures from copolymer P1 to terpolymers P4, while further increasing the 2,2-bithiophene feed ratio decreased the PCE.

Glucose-triggered stomatal closure is dependent on basal ABA signaling through PYR/RCAR receptors, CDPK6, and glucose signaling mediated by hexokinase1 (HXK1) in Arabidopsis., Sugars play important roles in regulating plant growth, development, and stomatal movement. Here, we found that glucose triggered stomatal closure in a dose- and time-dependent manner in Arabidopsis. Pharmacological data showed that glucose-induced stomatal closure was greatly inhibited by catalase [CAT; a reactive oxygen species (ROS) scavenger], diphenyleneiodonium chloride (DPI; an NADPH oxidase inhibitor), lanthanum chloride (LaCl3; a Ca2+ channel blocker), EGTA (a Ca2+ chelator), and two nitrate reductase (NR) inhibitors, tungstate and sodium azide (NaN3), while it was not affected by salicylhydroxamic acid (SHAM; a peroxidase inhibitor). Moreover, glucose induced ROS and nitric oxide (NO) production in guard cells of Arabidopsis. The ROS production was almost completely removed by CAT, strongly restricted by DPI, and was not affected by SHAM. NO production was partially suppressed by tungstate and NaN3, and the levels of NO were significantly reduced in the nia1-1nia2-5 mutant. Additionally, glucose-triggered stomatal closure was significantly impaired in gin1-1, gin2-1, pyr1pyl1pyl2pyl4, abi1-1, ost1, slac1-4, cpk6-1, and nia1-1nia2-5 mutants. Likewise, the reductions in leaf stomatal conductance (gs) and transpiration rate (E) caused by glucose were reversed in the above mutants. These results suggest that glucose-triggered stomatal closure may be dependent on basal signaling through PYR/RCAR receptors and hexokinase1 (HXK1).

Rupestrisine A (1), an unprecedented heteroyohimbine-kopsinine type dimeric indole alkaloid, and rupestrisine B (2), the first example of yohimbine-kopsinine type bisindole alkaloid, were isolated from Alstonia rupestris. Their structures were elucidated based on 1D and 2D-NMR, MS, ECD, FTIR and UV spectroscopic data. Compound 1 showed moderate activity of inhibiting NO production of RAW264.7 cells induced by lipopolysaccharide with an IC50 value of 17.5 ± 1.6 μM.

Background: The Malaysian government reacted to the pandemic’s economic effect with the Prihatin Rakyat Economic Stimulus Package (ESP) to cushion the novel coronavirus 2019 (COVID-19) impact on households. The ESP consists of cash assistance, utility discount, moratorium, Employee Provident Fund (EPF) cash withdrawals, credit guarantee scheme and wage subsidies. A survey carried out by the Department of Statistics Malaysia (DOSM) shows that households prefer different types of financial assistance. These preferences forge the need to effectively customise ESPs to manage the economic burden among low-income households. In this study, a recommender system for such ESPs was designed by leveraging data analytics and machine learning techniques. Methods: This study used a dataset from DOSM titled “Effects of COVID-19 on the Economy and Individual - Round 2,” collected from April 10 to April 24, 2020. Cross-Industry Standard Process for Data Mining was followed to develop machine learning models to classify ESP receivers according to their preferred subsidies types. Four machine learning techniques—Decision Tree, Gradient Boosted Tree, Random Forest and Naïve Bayes—were used to build the predictive models for each moratorium, utility discount and EPF and Private Remuneration Scheme (PRS) cash withdrawals subsidies. The best predictive model was selected based on F-score metrics. Results: Among the four machine learning techniques, Gradient Boosted Tree outperformed the rest. This technique predicted the following: moratorium preferences with 93.8% sensitivity, 82.1% precision and 87.6% F-score; utilities discount with 86% sensitivity, 82.1% precision and 84% F-score; and EPF and PRS with 83.6% sensitivity, 81.2% precision and 82.4% F-score. Households that prefer moratorium subsidies did not favour other financial aids except for cash assistance. Conclusion: Findings present machine learning models that can predict individual household preferences from ESP. These models can be used to design customised ESPs that can effectively manage the financial burden of low-income households.

The origin and tectonic evolution of the early Paleozoic arc terranes abutting the northern margin of the North China Craton (NCC) are widely debated. This paper presents detrital zircon U–Pb and Hf isotopic data of early Paleozoic strata in the Zhangjiatun arc terrane of central Jilin Province, northeast (NE) China, and compares them with the Bainaimiao and Jiangyu arc terranes abutting the northern margin of the NCC. Detrital zircons from early Paleozoic strata in three arc terranes exhibit comparable age groupings of 539–430, 1250–577, and 2800–1600 Ma. The Paleoproterozoic to Neoarchean ages and Hf isotopic composition of the detrital zircons imply the existence of the Precambrian fragments beneath the arc terranes. Given the evidences from geology, igneous rocks, and detrital zircons, we proposed that the early Paleozoic arc terranes abutting the northern margin of the NCC are a united arc terrane including the exotic Precambrian fragments, and these fragments shared a common evolutionary history from Neoproterozoic to early–middle Paleozoic.

Impact of migration test method on the release of nanocomponent from nano-polymer composite films intend for food contact is seldom addressed. In this study, release of silver from nanosilver-polyethylene composite films into 3% acetic acid under different migration test methods were investigated, with the aim to understand the effect of exposure condition on silver release. The following test protocols were designed for the experiment: single-sided contact versus two-sided contact, more versus fewer cut edges, and glass migration cell versus metal one. The results show that samples under two-sided contact had higher silver release than that under one-sided contact. Besides, increasing the number of cut edges largely increased the release of silver, while using metal instead of glass migration cell significantly reduced the release. Furthermore, partially floated films have lower silver release than that of totally immersed films. As a conclusion, impact of migration test method on the release of nanocomponent is different from that on the migration of common migrants and therefore, exposure condition should be carefully taken into account in the design of migration test for nanosilver-polyethylene composite films to minimize any potential negative impact on obtaining comparable results.

This study presents new zircon U–Pb ages and geochemical data for Neoproterozoic granitoids in the Songnen–Zhangguangcai Range Massif (SZRM) of NE China. This dataset provides insights into the Neoproterozoic tectonic setting of the SZRM and the links between this magmatism and the evolution of the Rodinia supercontinent. The zircon U–Pb dating indicates that the Neoproterozoic magmatism within the SZRM can be subdivided into two stages: (1) a ∼917–911 Ma suite of syenogranites and monzogranites, and (2) an ∼841 Ma suite of granodiorites. The 917–911 Ma granitoids contain high concentrations of SiO2 (67.89–71.18 wt.%), K2O (4.24–6.91 wt.%), and Al2O3 (14.89–16.14 wt.%), and low concentrations of TFe2O3 (1.63–3.70 wt.%) and MgO (0.53–0.88 wt.%). They are enriched in the light rare earth elements (LREE) and the large ion lithophile elements (LILE), are depleted in the heavy REE (HREE) and the high field strength elements (HFSE; e.g., Nb, Ta, and Ti), and have slightly positive Eu anomalies, indicating that they are geochemically similar to high-K adakitic rocks. They have zircon eHf (t) values and TDM2 ages from −4.4 to +1.5 and 1915 Ma to 1592 Ma, respectively, suggesting that they were derived from a primary magma generated by the partial melting of ancient thickened lower crustal material. In comparison, the 841 Ma granodiorites contain relatively low concentrations of Al2O3 (14.50–14.58 wt.%) and K2O (3.27–3.29 wt.%), relatively high concentrations of TFe2O3 (3.78–3.81 wt.%) and the HREE, have negative Eu anomalies, and have zircon eHf (t) values and TDM2 ages from −4.7 to +1.0 and 1875 to 1559 Ma, respectively. These granodiorites formed from a primary magma generated by the partial melting of ancient crustal material. The ∼917–911 Ma magmatism within the SZRM is inferred to have formed in an orogenic setting, whereas the ∼841 Ma magmatism formed in an anorogenic setting related to either a post-orogenic tectonic event or the onset of Neoproterozoic continental rifting. It is proposed that the microcontinental massifs within the eastern central Asian orogenic belt of NE China formed during or following the final stage of assembly of Rodinia before rifting away from the Tarim Craton in response to the Rodinia breakup.

Coupling of multiple environmental factors in the engineering sector, in particular, joint distribution modeling based on a high-dimensional environmental dataset containing circular data is very topical. We propose a modeling framework applicable to the 3D joint distribution of circular-linear-linear (C-L-L) dataset consisting of a parametric model based on copulas and a nonparametric kernel density estimation model. In the parametric model, the pair-copula decomposition concept of vine copulas represents the C-L-L dependence structure as a combination of C-L and L-L ones modeled by C-L and L-L copulas, respectively. This allows one to solve the circular variable's cyclicity problem in the trivariate joint distribution and assess C-L and L-L dependencies between paired variables in the C-L-L dataset. A case study is used to establish the joint distribution model based on annual observations of wind direction, wind speed, and air temperature via the structural health monitoring system of the Jiangyin Bridge, China. The modeling framework validity is proved by the case study, which reveals significant differences in the conditional univariate distribution features of wind speed and air temperature, and conditional joint distribution features of two variables under different wind directions. Therefore, in engineering problems sensitive to the wind direction, the latter's effect cannot be neglected.