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Lake-level changes can significantly affect paleoenvironmental evolution, resource occurrence, terrestrial carbon budget, and biodiversity in continental basins. Climate is one of the most critical factors controlling lake-level changes. Paleoclimate of the Early Jurassic has been evidenced by oscillating icehouses to (super) greenhouses with interrupted intermittent extreme climatic events (hyperthermal and cooling), e.g., the Toarcian oceanic anoxic event (~183 Ma) and the late Pliensbachian cooling event (~185 Ma). Lake-level evolution and hydrologic cycling on Earth's surface during the Early Jurassic icehouses-to-(super)greenhouses are thus far poorly understood due to a lack of continuous high-resolution nonmarine evidence. Here we present a super-long nonmarine lake level record for this pivotal interval from the early Pliensbachian to Toarcian by sedimentary noise modeling, and construct a 16.7-Myr-long astronomical time scale (174.2 Ma to 190.9 Ma) based on cyclostratigraphy analysis of rock color datasets (CIE b*) of the Qaidam Basin. Our results document lake-level oscillations on a 5-to 10-million-year (Myr) scale which shows a pronounced correlation with long-term climate variation and extreme climatic events, and 1- to 2.5-Myr-scale lake-level changes that are prominently paced by the 2.4-Myr long-eccentricity forcing and the 1.2-Myr obliquity forcing. At the Pliensbachian Stage, the 1.2-Myr-scale lake-level changes are in phase with the coeval sea-level variations. Orbitally forced growth and decay of the ephemeral or permanent ice sheets in polar regions are interpreted to control the synchronous ups-and-downs of continental lake level and global sea level. However, during the Toarcian ice-free greenhouses to (super)greenhouses, the 1.2-Myr-scale lake-level variations show an anti-phase relationship with global sea level, indicating a 'seesaw' interaction between continental reservoirs (lakes and groundwater) and global oceans. The 2.4-Myr long-eccentricity cycles mainly regulate variations of lake level and sea level by controlling the growth and decay of small-scale continental ice sheets, which is especially notable during the Pliensbachian Stage. These findings indicate a remarkable transition of hydrological cycling pattern during the Pliensbachian-Toarcian icehouses to (super)greenhouses, which provides new perspectives and evidence for investigating the hypothesis of global sea-level changes (e.g., glacio-eustasy and aquifer-eustasy) and long-period astronomical forcing in nonmarine stratigraphy. [ABSTRACT FROM AUTHOR]

An access-transistor-free (0T1R) structure has been reported to have great advantages in reducing the area of the phase-change memory cell, but leakage current has limited its application in large-scale arrays. In this study, a GeTe/InP heterostructure is proposed as the integration of a selector and phase-change cell in a 0T1R structure. The effect of establishing a GeTe/InP heterostructure is explored based on first-principles study, and the performance is further optimized by doping. The results show that, compared with GeTe, the band gap value of the GeTe/InP heterostructure decreases, and the space charge region forms at the interface, which effectively suppresses the leakage current of the 0T1R structure. In addition, to further improve the performance of GeTe/InP, group III-V elements are used as substitutional dopants at the P site. We find that when N and B dopants are used, the electrical conductivity of GeTe/InP and the charge transfer between interfaces are enhanced. The current–voltage characteristic curves show that the establishment of the GeTe/InP heterostructure and doping significantly improved the nonlinear coefficient of the phase-change memory cell, which can better suppress the leakage current in the 0T1R structure. [ABSTRACT FROM AUTHOR]

In order to reduce the volatilization of Bi2O3 in the sintering process due to low melting point, and improve the microstructure uniformity of samples obtained by ball milling, ZnO–Bi2O3 varistor ceramics were prepared by two-step sintering method with sintering temperature lower than 1000 °C. This two-step method was contrary to most previous research, which owed lower turning point temperature T1. The samples were first heated up to T1(T1 = 750 °C, 800 °C and 850 °C, respectively) before sintering at T2(T2 = 950 °C), while T1 was selected based on the sintering characteristics. Samples prepared by traditional one-step sintering were used as reference. Microstructure and electrical properties of ceramics were investigated to discuss the enhanced effect of two-step sintering regimes. Results showed that the two-step sintered samples had higher breakdown voltage, higher relative density and uniform microstructure. The best performance was obtained when T1 was 800 °C and T2 was 950 °C, the breakdown voltage was 883 V/mm, the nonlinear coefficient was 10.1, the leakage current was below 0.1 μA. This special two-step sintering method also contributed to avoiding high-temperature and obtain better composite performance. The work may supply useful reference for the exploration and application of low-temperature silver co-fired multilayer chip device. [ABSTRACT FROM AUTHOR]

Extending the benefits of tumor molecular profiling for all cancer patients requires a comprehensive analysis of tumor genomes across distinct patient populations worldwide. In this study, we perform deep next-generation DNA sequencing (NGS) from tumor tissues and matched blood specimens from over 10,000 patients in China by using a 450-gene comprehensive assay, developed and implemented under international clinical regulations. We perform a comprehensive comparison of somatically altered genes, the distribution of tumor mutational burden (TMB), gene fusion patterns, and the spectrum of various somatic alterations between Chinese and American patient populations. Here, we show 64% of cancers from Chinese patients in this study have clinically actionable genomic alterations, which may affect clinical decisions related to targeted therapy or immunotherapy. These findings describe the similarities and differences between tumors from Chinese and American patients, providing valuable information for personalized medicine. Understanding the mutation landscape of cancer may enable the development of more targeted therapies. Here, the authors sequence a panel of genes in a large Asian cohort and compare to American cohorts and find 64% of the Asian patients have actionable mutations. [ABSTRACT FROM AUTHOR]

The two-dimensional guided filter is a linear time-varying filter that can filter the noise and retain the detailed information of the image better. It is widely used in image denoising. However, in its application process, it is necessary to calculate the parameters required by filtering in real time according to the data. The operation process involves complex floating point multiplication and division operations, which leads to the high complexity of hardware implementation and excessive resource overhead. It is also difficult to improve the comprehensive speed of the system, which is not good for real-time signal processing. Aiming at the above problems, based on the theory of guided filtering and taking full advantage of the parallelism of FPGA, we proposed a two-dimensional guided filter hardware optimization system based on FPGA. In the system, first, the original image data are cached in real time to reduce the occupation of other hardware resources. Then, the complex mean and variance operations are split into simple sum operations, which reduces the computational complexity. Finally, the system is designed by using serial and parallel flow operation methods, which effectively improve the operation speed of the system. The results show that the operating frequency of the optimized hardware system is up to 146.953 MHz, which is 28.322 MHz higher than that of the original guided filtering algorithm. [ABSTRACT FROM AUTHOR]

Purpose: Dietary sodium and potassium intake are associated with stroke, but the potential mechanisms are unclear. We aimed to study the association between sodium and potassium intake and subclinical cerebrovascular health in hypertensive older males using multimodal magnetic resonance imaging. Methods: A total of 189 hypertensive male subjects without previous cardiovascular or cerebrovascular disease were included. Daily urinary sodium and potassium excretion were estimated from a fasting spot urine sample using a formula approach. A dedicated cerebrovascular health imaging protocol including vessel wall imaging, angiography, arterial spin labeling imaging and T2-weighted fluid-attenuated inversion recovery imaging was performed to study intracranial atherosclerosis, vascular rarefaction (defined as fewer discernible vessels on angiography), brain perfusion and small vessel disease, respectively. Results: The mean age was 64.9 (± 7.2) years. The average daily urinary and potassium excretion was 4.7 (± 1.4) g/L and 2.1 (± 0.5) g/L, respectively. Increased urinary sodium excretion was associated with decreased cerebral blood flow and elevated urinary potassium excretion was associated with reduced prevalence of intracranial plaque. The associations remained significant after adjusting for covariates, even including blood pressure control. Quadratic regression analysis indicated a marginally significant U-shaped association between urinary sodium intake and white matter hyperintensity, which lost significance in fully adjusted models. No significant association of urinary sodium and potassium excretion with other cerebrovascular health measures was noted. Conclusion: We concluded that in hypertensive older males without overt cardiovascular disease, increased sodium intake and reduced potassium intake are associated with impaired subclinical cerebrovascular health. [ABSTRACT FROM AUTHOR]

Objectives: The study aimed to analyze the association between hypertension control and subclinical cerebrovascular health using a comprehensive multimodal imaging approach. Methods: The study included 200 hypertensive older males without previous cardiovascular diseases. Clinic blood pressure (BP) was measured using a standard approach. Cerebrovascular health was evaluated using magnetic resonance imaging in the following four aspects: Intracranial atherosclerosis as determined by vessel wall imaging; Vascular rarefaction (defined as less discernible vessels on angiography) was evaluated using a custom-developed technique. Cerebral blood flow (CBF) and white matter hyperintensity (WMH) were assessed using arterial spin-labeling imaging and fluid-attenuated inversion recovery imaging, respectively. Results: A total of 189 subjects had MRI scans. The mean age was 64.9 (± 7.2) years. For intracranial atherosclerosis, there was a significant association between uncontrolled hypertension and presence of intracranial plaque. When systolic and diastolic BP were analyzed separately, the association remained significant for both. For vascular rarefaction, uncontrolled hypertension was associated with less discernible vessel branches or shorter vessel length on angiography. Further analysis revealed that this is due to uncontrolled diastolic BP, but not uncontrolled systolic BP. There was an association between uncontrolled hypertension and reduced CBF, which was also mainly driven by uncontrolled diastolic BP. We also found that uncontrolled diastolic BP, but not uncontrolled systolic BP, was associated with increased WMH volume. Conclusions: Uncontrolled hypertension was associated with subclinical cerebrovascular injury globally, with both small and medium-to-large arteries being affected. Key Points: • In this study, we leveraged the advantage of a series of cutting-edge MR imaging and analysis techniques and found uncontrolled hypertension is associated with subclinical globally compromised cerebrovascular health. • The detrimental consequences of uncontrolled BP affect not only the small vessels but also the medium-to-large arteries, and uncontrolled systolic and diastolic BP are both independently associated with certain types of cerebrovascular injury. • Our data suggest that cerebrovascular health is impaired globally in uncontrolled hypertension before the onset of stroke. [ABSTRACT FROM AUTHOR]

Wood-based sandwich composite with a paper honeycomb core, especially for thick boards, has the advantage of high strength-to-weight ratio for the use in lightweight furniture products, interior walls etc. Employing both theoretical and experimental methods, this study investigated the influencing factors of various failure modes and its transition to obtain optimized structural parameters after a quasi-static load was applied. The results reveal that the skins of MDF are too strong for the paper honeycomb core. Both failure modes are caused by weak core properties. If the thickness or strength of the skins could be reduced or the core strength could be reinforced, then optimal failure mode of simultaneous core and skin failure could be reached. The intersection point of three transition lines is the best combination of structural parameters, meaning highest strength-to-weight ratio. At this point, failure of core shear, indentation and face fracture occurs simultaneously. The distance from a structural parameter to intersection is an effective index to express the degree of optimization for the strength-to-weight ratio of composites. Specimens close to the intersection point have optimal structural parameters and high strength-to-weight ratio. On application level, the optimum strength-to-weight ratio could be obtained easily by adjusting the surface or core thickness, if the materials were fixed first. [ABSTRACT FROM AUTHOR]

A series of silica-pillared zirconium phosphate materials with ordered structure were synthesized using hexadecylamine (HDA) as expanding agent, dodecyl dimethyl benzyl ammonium chloride (DDBAC) as template agent and tetraethyl orthosilicate (TEOS) as silica source. The textural properties of the materials can be effectively controlled by adjusting the dosage of HDA, DDBAC and TEOS. Furthermore, a template-directing self-assembly mechanism was proposed based on the synthesis. In the epoxidation of methyl soyate, the prepared materials showed excellent performance with 95.9 % conversion of double bonds and 84.7 % epoxy selectivity. This result is determined by the large surface area and the ordered interlayer structure. Graphical Abstract: Series silica-pillared zirconium phosphate materials with ordered structure were synthesized. The textural properties of the materials can be effectively controlled by adjusting the dosage of each reaction species. A template-directing self-assembly mechanism was proposed based on the synthesis. The materials show excellent catalytic performance on the epoxidation of methyl soyate.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The ethylene response factor (ERF) genes are a subfamily of transcription factors containing a single AP2/ERF domain, which play crucial roles in plant development and response to biotic and abiotic stresses. In the present study, 16 ERF genes (named ThERF1-ThERF16) were isolated from Tamarix hispida, and their expression in response to salt, drought and ABA treatment was investigated using real-time RT-PCR. The results showed that all 16 ERFs are expressed in root, stem and leaf tissues, but the individual transcript levels vary strongly in roots, stem or leaves. Among these ThERFs, ThERF1 is the most abundant in roots, stems and leaves, indicating that it may play a more important physiological role than the other ThERF genes. The 16 ThERF genes are all highly differentially expressed in leaves, stems or roots under salt and drought stress, demonstrating that they are involved in the salt and drought stress responses. Under ABA treatment, expression of the ThERF genes was mainly down-regulated in roots, but induced in leaves or stems, suggesting that they are also involved in the ABA stress response. These results strongly suggest that ThERFs are abiotic stress response genes that may play important roles in the stress tolerance of T. hispida. [ABSTRACT FROM AUTHOR]

A single-layer double-walled carbon nanotube (DWNT) membrane, with 100 cm² in area, 50 nm in thickness, was spread by adding a few drops of ethanol (or acetone) on the purified DWNTs. Compared with acetone, ethanol Is more efficient in spreading DWNT films. The spreading rate of DWNT membrane Increases with the ethanol concentration, and it also first increases with temperature (below 60 °C), then decreases as the temperature rises to above 60 °C. [ABSTRACT FROM AUTHOR]

In this study, daidzein long-circulating liposomes (DLCL) were prepared using the ultrasonication and lipid film-hydration method. The optimized preparation conditions by the orthogonal design was as follows: 55 to 40 for the molar ratio of soybean phosphatidylcholine (SPC) to cholesterol, 1 to 10 for the mass ratio of daidzein to total lipid (SPC and cholesterol) (w:w), the indicated concentration of 5% DSPE-mPEG2000 (w:w), 50 °C for the hydration temperature, and 24 min for the ultrasonic time. Under these conditions, the encapsulation efficiency and drug loading of DLCL were 85.3 ± 3.6% and 8.2 ± 1.4%, respectively. The complete release times of DLCL in the medium of pH 1.2 and pH 6.9 increased by four- and twofold of that of free drugs, respectively. After rats were orally administered, a single dose of daidzein (30 mg/kg) and DLCL (containing equal dose of daidzein), respectively, and the MRT0−t (mean residence time, which is the time required for the elimination of 63.2% of drug in the body), t1/2 (the elimination half-life, which is the time required to halve the plasma drug concentration of the terminal phase), and AUC0−t (the area under the plasma drug concentration-time curve, which represents the total absorption after a single dose and reflects the drug absorption degree) of daidzein in DLCL group, increased by 1.6-, 1.8- and 2.5-fold as compared with those in the free group daidzein. Our results indicated that DLCL could not only reduce the first-pass effect of daidzein to promote its oral absorption, but also prolong its mean resident time to achieve the slow-release effect. [ABSTRACT FROM AUTHOR]

Considering the influence of the preferential degree, the hesitation psychology of customers and the heterogeneity of underlying networks in preferential information spreading, we propose a novel model called AHFB (adherent–hesitator–forwarder–beneficiary) model to illustrate the dynamic behaviors of preferential information spreading on scale-free networks. The mean-field theory is adopted to describe the formulas of AHFB model. To begin with, we analyze the spreading dynamics of preferential information. Then we determine the basic reproductive number and equilibria by the next generation matrix method. The relationship among the basic reproductive number, preferential degree, and hesitation parameter is also analyzed. In addition, the globally asymptotical stability of information-eliminate equilibrium and the permanence of the preferential information spreading are proved in detail. Furthermore, a preferential information competition model is proposed, and the corresponding dynamic behaviors are studied. We have found that under certain conditions, a greater competitive advantage can be achieved by improving a certain range of preferential strengths. Numerical simulations are also presented to verify and extend theoretical results. [ABSTRACT FROM AUTHOR]

Previous studies suggested that the reactive hyperemia index (RHI) is a promising cardiovascular risk predictor. We aimed to evaluate clinical determinants of RHI and its association with circulating endothelial injury and cardiac markers in hemodialysis patients. Among 368 patients recruited, RHI was evaluated by peripheral arterial tonometry (PAT) on a midweek nondialysis day. Clinical determinants of RHI were explored by multiple stepwise regression analysis and associations between RHI and circulating markers were evaluated by general linear models. The major cause of a failed PAT test was poor signal (82.1%). Intraclass correlation coefficient for reproducibility evaluation was 0.74. Multiple regression analysis showed traditional clinical factors only explained 7% of the variance of natural logarithm RHI (LnRHI) in the patients. In association analyses, LnRHI showed significant positive associations with Von Willebrand factor (vWF) (p = 0.04) and tissue factor (p = 0.047). It also associated positively with troponins (p ≤ 0.02 for both). In conclusion, performance of the PAT test was acceptable in dialysis patients and traditional clinical variables had very limited influence on RHI in these subjects. Among a panel of conventional endothelial injury markers, RHI showed very modest associations with only vWF and tissue factor. RHI associated positively with troponins in the patients. [ABSTRACT FROM AUTHOR]