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Leukoaraiosis (LA) appears as white matter hyperintensities on T2-weighted brain magnetic resonance imaging scans. Age and hypertension are considered the primary risk factors for LA, but its pathogenesis remains uncertain. This study aims to investigate the correlation between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and LA. A total of 140 patients with LA and 136 neuroimaging alteration-free controls were recruited in a case–control study. ACE I/D polymorphism was determined using the polymerase chain reaction method. The allele and genotype distributions of the ACE I/D polymorphism were significantly different between subjects with and without LA. Significant difference was observed in the genotypic distribution between LA patients and controls for recessive and additive models. A statistically significant association remained apparent after adjusting for potential risk factors (D/D vs. I/D + I/I: adjusted OR 3.251, 95% CI 1.185–8.918; D/D vs. I/I: adjusted OR 3.277, 95% CI 1.187–9.047). Our results indicate that the D/D genotype and D allele are important risk factors for LA. Future studies with larger populations are needed to validate our results. [ABSTRACT FROM AUTHOR]

High-altitude hypoxia acclimatization requires whole-body physiological regulation in highland immigrants, but the underlying genetic mechanism has not been clarified. Here we use sheep as an animal model for low-to-high altitude translocation. We generate multi-omics data including whole-genome sequences, time-resolved bulk RNA-Seq, ATAC-Seq and single-cell RNA-Seq from multiple tissues as well as phenotypic data from 20 bio-indicators. We characterize transcriptional changes of all genes in each tissue, and examine multi-tissue temporal dynamics and transcriptional interactions among genes. Particularly, we identify critical functional genes regulating the short response to hypoxia in each tissue (e.g., PARG in the cerebellum and HMOX1 in the colon). We further identify TAD-constrained cis-regulatory elements, which suppress the transcriptional activity of most genes under hypoxia. Phenotypic and transcriptional evidence indicate that antenatal hypoxia could improve hypoxia tolerance in offspring. Furthermore, we provide time-series expression data of candidate genes associated with human mountain sickness (e.g., BMPR2) and high-altitude adaptation (e.g., HIF1A). Our study provides valuable resources and insights for future hypoxia-related studies in mammals. The mechanisms underlying high-altitude acclimatization remain unclear. Here authors use the sheep model to reveal multi-tissue temporal dynamics of gene transcription and regulation during acclimatization, and provide resources for hypoxia-related studies. [ABSTRACT FROM AUTHOR]

Summary: Background: Neuronal intranuclear inclusion disease (NIID) is a rare highly heterogeneous disease. In this paper, we present a case of NIID featured in cortical involvement in left hemisphere of brain and the imaging changes in the process of the disease. Case presentation: A 57-year-old female was hospitalized due to recurrent attacks of headache with cognitive impairment and tremor for 2 years. The symptoms of headache episodes were reversible. The characteristic radiologic change was high intensity signal involving the grey matter-white matter junction on the brain diffusion-weighted imaging (DWI), which existed in the frontal lobe and then extended backwards. Atypical features on fluid-attenuated inversion recovery (FLAIR) sequences showing small patchy high signals in the cerebellar vermis. High signals and edema were detected on FLAIR images along the cortex of the left occipito-parieto-temporal lobes, expanding and gradually shrinking in the follow-up visit. Besides, cerebral atrophy and bilateral symmetrical leukoencephalopathy were also detected. Skin biopsy and genetic testing confirmed the diagnosis of NIID. Conclusion: Except for typical radiological change strongly suggesting NIID, it is also necessary to notice the insidious symptoms of NIID combining with some atypical imaging features to make an early diagnosis. Skin biopsies or genetic testing should be carried out early in patients with highly suspected NIID. [ABSTRACT FROM AUTHOR]

We report a set of direct numerical simulation results on Rayleigh-Bénard-Marangoni (R-B-M) flow of cold water in the cylindrical pools. The heat transfer between the free surface and the environment is considered. The aspect ratio Г of the cylindrical pool varies from 2 to 8. Rayleigh (Ra) and Biot (Bi) numbers are respectively confined in Ra ≤ 104 and 0 < Bi ≤ 50. The flow onset critical Ra is determined and the influences of Bi and the density inversion parameter (Θm) on the critical Ra are analyzed. The primary bifurcation flow structures of R-B-M flow are shown and the evolution of the flow structures with Ra and Bi at different Θm is observed. Furthermore, the heat transfer ability is estimated by Nusselt number. The results indicate that the critical Ra of the flow onset increases with increasing Bi and Θm. But it decreases with the increase of Г. The primary bifurcation pattern is multicellular flow. With increasing Г, the number of flow cells in multicellular flow increases fast. With increasing Ra, the up-triangular and up-quadrilateral flow structures appear at Г = 4, and finally transits to the up one-torus. With increasing Ra and Г, and decreasing Θm, average Nusselt number increases monotonically. However, with increasing Bi, it first increases, and then decreases. [ABSTRACT FROM AUTHOR]

Storm surges are cataclysmic natural disasters that occur along the coasts and are usually accompanied by large waves. The effects of coupled storm surges and waves can pose a significant threat to coastal security. Previous laboratory studies on the effects of storm surges and waves on coastal structures have typically utilized steady water levels and constant wave elements. An indoor simulation of the coupled processes of tides and waves is developed by adding a tide generation system to an existing laboratory wave basin to model continuous dynamic tide levels so that tide generation and wave-making occur synchronously in the pool. Specific experimental methods are given, which are applied to further study waves overtopping on artificial sea dikes and coastal flooding evolution under the coupled actions of tides and waves. The results of the overtopping discharge obtained by the test with a dynamic water level are compared with those obtained from steady water level tests and the existing empirical formula. In addition, the impacts of ecological coastal shelterbelts and structures on coastal flood processes and distributions are also investigated. The proposed simulation methods provide a new approach for studying the effects of storm surges and waves on coastal areas. The study also aims to provide a reference for coastal protective engineering. [ABSTRACT FROM AUTHOR]

In order to understand the effect of the radius ratio on thermocapillary-buoyancy convection, a series of experimental observations on thermocapillary-buoyancy convection of 0.65cSt and 1cSt silicone oils have been conducted in annular pools with a smaller heating inner cylinder and the radius ratio of 0.25. The results show that the rotating petal-like structure or spoke pattern first appears on the free surface when thermocapillary-buoyancy convection destabilizes. As the Marangoni number increases, the spoke pattern becomes oscillating at the depth of 6–7 mm and the oscillating frequency is decreased compared with the results in the liquid pool with a radius ratio of 0.5. The wavenumber of the flow pattern decreases when the radius ratio decreases from 0.5 to 0.25. Especially at the liquid depth of 7–8 mm, a mode switching of the flow patterns has been observed and the flow pattern becomes more like cellular structures in cylindrical pools instead of the spoke pattern with the increasing Marangoni number. With the increase of the Prandtl number, this flow transition becomes difficult. Besides, the short spokes appear near the inner cylinder at a large Marangoni number and the deep fluid layer. Based on the experimental results, the general relationship of the threshold complex with the dynamic Bond number and the radius ratio is achieved. [ABSTRACT FROM AUTHOR]

With the increasing construction of artificial beach in coastal areas, it is of practical significance to study the beach surface deformation of artificial beach profile. Previous studies only focus on a single wave dynamic factor, and it is difficult to predict the beach deformation of artificial beach profile under the storm surge—wave co-action. To solve this problem, the cross-section physical model test method was used to study the beach surface deformation of a typical artificial beach profile in Shuangdao Bay, Weihai, Shandong Province, after continuous wave actions till they stabilize. The characteristics of beach surface deformation under the conditions of constant water levels, ladder-shaped water level combined with corresponding wave elements and storm surge—wave co-action are compared and analyzed. A beach profile model which satisfies the theory of Bruun model is proposed. The test results show that the maximum scour depth of beach under storm surge—wave co-action is smaller and the scour range is obviously larger than that under the condition of constant water levels or ladder-shaped water level. The evaluation of the maximum scour depth by traditional model test tends to be conservative while the evaluation of the scour range is insufficient. The research results can provide scientific reference for designing artificial beaches. [ABSTRACT FROM AUTHOR]

This paper presented a set of direct numerical simulations on the thermocapillary flow instability of moderate-Prandtl number fluids in annular pools heated from inner cylinder. The emphasis is on the aspect ratio dependence of the critical Marangoni number of flow destabilization and the formation mechanism of the different flow patterns. It was found that the two-dimensional axisymmetric steady flow will bifurcate into three types of oscillatory flows, including the oscillatory concentric rings, the alternating straight spoke and the rotating wave patterns. The bifurcation process depends mainly on the aspect ratio of the annular pool when the radius ratio is fixed. With the increase of the aspect ratio, the first instability flow pattern is oscillatory concentric rings and the corresponding critical Marangoni number and the oscillatory frequency decrease first, and then increase slightly. When the flow pattern transits to the alternating straight spoke pattern at the aspect ratio of 0.415, there are an abrupt increase of the critical Marangoni number and a sudden decrease of the oscillatory frequency. Furthermore, when the rotating wave pattern appears, the critical Marangoni number decreases gradually, but the corresponding oscillatory frequency has only a slight decrease. [ABSTRACT FROM AUTHOR]

Recently, a new monolayer Group III–V material, two-dimensional boron phosphide (BP), has shown great potential for energy storage and energy conversion applications. We study the thermoelectric properties of BP monolayer as well as the effect of functionalization by first-principles calculation and Boltzmann transport theory. Combined with a moderate bandgap of 0.90 eV and ultra-high carrier mobility, a large ZT value of 0.255 at 300 K is predicted for two-dimensional BP. While the drastically reduced thermal conductivity in hydrogenated and fluorinated BP is favored for thermoelectric conversion, the decreased carrier mobility has limited the improvement of thermoelectric figure of merit. [ABSTRACT FROM AUTHOR]

Atherosclerosis was an important pathophysiological basis of atherothrombotic stroke, and phosphodiesterase 4D (PDE4D) polymorphism (SNP83/rs966221) was reported to be associated with the susceptibility to atherothrombotic stroke. Aim of the present study was to explore the potential association between SNP83 and carotid atherosclerosis (CAS). 204 southern Chinese Han participants were divided into two groups according to the carotid intima-media thickness (IMT) of the carotid artery: CAS group (carotid IMT ≥ 1.0 mm) and non-CAS group (carotid IMT < 1.0 mm). Carotid IMT was measured by color Doppler ultrasound. The PDE4D SNP83 polymorphism was determined by SNaPshot technique. Our study found that SNP83 was associated significantly with CAS susceptibility under the dominant, overdominant and codominant models. After adjusting for age, gender, low-density lipoprotein cholesterol, Hemoglobin A1c, cigarette smoking, hypertension history, and diabetes mellitus history, the association still remained significant (dominant model: crude OR = 2.373, 95% CI: 1.268–4.442, P = 0.007; adjusted OR = 3.129, 95% CI: 1.104–8.866, P = 0.032; overdominant model: crude OR = 1.968, 95% CI: 1.043–3.714, P = 0.037; adjusted OR = 2.854, 95% CI: 1.005–8.108, P = 0.049; codominant: crude OR = 2.102, 95% CI: 1.110–3.979, P = 0.023; adjusted OR = 2.984, 95% CI: 1.047–8.502, P = 0.041). Carotid IMT of carriers with CT + CC genotypes was higher than carriers with TT genotype (P = 0.016). Our results indicated that the SNP83/rs966221 located on PDE4D gene was significantly associated between CAS susceptibility and carotid IMT independently of conventional risk factors in a southern Chinese Han population. [ABSTRACT FROM AUTHOR]

This paper presents a series of numerical simulations on the effect of heat dissipation on the thermocapillary convection of a low Prandtl number (Pr = 0.011) fluid in an annular pool heated from its inner cylinder. The radius ratio and the aspect ratio of the annular pool set as η = 0.5 and ε = 0.1, respectively. The results show that with the increase of Biot number, the isotherms of the two-dimensional basic flow are seriously compressed near the hot inner cylinder and the thermocapillary flow pattern will be impaired. With the increase of Marangoni number, the thermocapillary convection first evolves from the basic flow to a three-dimensional stationary flow with longitudinal stationary stripes on the free surface, and then to a three-dimensional oscillatory flow featured with the combination of stationary stripes and azimuthal waves, which is caused by the mutual effect of the radial convection, azimuthal local flow and heat dissipation. After the flow destabilization, the amplitude of temperature fluctuation increases and the wave number decreases with the increase of Marangoni number when the free surface is adiabatic. Furthermore, the temperature fluctuation pattern is changed due to the surface heat dissipation. In addition, with the increase of Biot number, the wave number almost keeps constant when Marangoni number is small, but it increases significantly at a large Marangoni number. [ABSTRACT FROM AUTHOR]

This paper presented a linear-stability analysis on thermocapillary-buoyancy convection in radially heated annular pool filled in 5cSt silicone oil / HT-70 two-layer fluids. The influences of the aspect ratio, radius ratio and thickness ratio on the flow stability were discussed. Results indicate that the system is most unstable when the thickness ratio is close to 0.375. Flow bifurcation appears when the thickness ratio varies from 0.625 to 0.875. Three corresponding destabilization mechanisms were revealed. Effect of buoyancy convection and the upper boundary condition on the flow stability were also analyzed. The upper rigid wall can enhance the flow stability in the annular two-layer system, especially when the thickness ratio is near 0.75. Furthermore, the buoyancy can greatly reduce the flow stability comparing with that under the microgravity condition. [ABSTRACT FROM AUTHOR]

A NiO flake and reduced graphene oxide sheet (NiO/RGO) composite was synthesized via an in situ ultrasonic agitation method after heat calcination in a nitrogen atmosphere. The NiO/RGO composite displayed a high reversible capacity of 825 mA h/g after 50 cycles at 100 mA/g, which was higher than the pure NiO flakes (197 mA h/g). The RGO sheets (115 mA h/g) used in lithium-ion batteries as anode materials. The NiO/RGO electrode showed excellent rate capacities that were higher than the pure NiO flakes and the RGO sheets electrodes within the same experimental conditions. These improvements could be attributed to the RGO sheets improved the electrical conductivity of NiO flakes and buffered the volume expansion of the NiO/RGO composite electrode during lithium cycling. [ABSTRACT FROM AUTHOR]

In this paper, a type of macroporous carbon (MPC) material was produced using water-soluble sodium carbonate (Na2CO3) as the template and glucose as the carbon precursor. After annealing in an argon atmosphere (Ar) at 700 °C, the samples exhibited specific surface areas up to 600 m2 g−1 with different proportions of sodium carbonate and glucose. When the samples were employed as anode materials in lithium-ion batteries, the electrodes delivered a stable reversible capacity at 200 mA g−1 and favourable cycling stability at 500 mA g−1. Moreover, all MPC samples exhibited excellent rate performances at 5000 mA g−1. [ABSTRACT FROM AUTHOR]

Fusiform shape MnO/C composite was fabricated for the first time by heat calcining of MnCO3/C precursor, which was produced via a two-step hydrothermal method using glycine, KMnO4 and glucose as reagents. When the composite applied in LIBs as anode materials, the electrodes deliver a reversible capacity as high as 691 mA h g−1 after 120 cycles at a current density of 100 mA g−1 and can retain a stable capacity of 187 mA h g−1 at 1000 mA g−1. Compared with pure MnO particles sample, the enhanced electrochemical performances of MnO/C electrodes were attributed to the carbon layers can effectively improve the transfer rate of electrons and buffer the volume expansion of MnO particles during the charge/discharge process. [ABSTRACT FROM AUTHOR]

The linear-stability analyses of thermocapillary flow in an annular two-layer system subjected to a radial temperature gradient were conducted. The annular pool with upper free surface and adiabatic bottom is filled with immiscible double layer liquid of 5cSt silicone oil / HT-70. The outer wall of the annular pool is heated and inner wall is cooled. The results indicate that the critical Marangoni number decreases with the increase of aspect ratio and radius ratio. The effect of the ratio of the lower liquid thickness to the total double layer thickness on the convection onset is complicated. The minimum critical Marangoni number is located near the thickness ratio of 0.125. Moreover, there is one Hopf bifurcation from the steady to oscillatory flow when the thickness ratio varies from 0.625 to 0.75. At the same time, two types of flow destabilizing mechanism are identified. Comparing with the results with upper rigid wall, it can be found that the stability of thermocapillary convection in annular two-layer system with the free surface reduces largely. [ABSTRACT FROM AUTHOR]

Through-hole TiO nanotube arrays (THTNA) are fabricated successfully by applying a large-voltage pulse (Δ V ≥ 40 V) at the end of anodization, and a mechanism is proposed that the fluoride-rich layer (FRL) between Ti substrate and nanotubes is the key factor for fabricating THTNA. In order to confirm the mechanism, the effects of temperature of voltage pulse on the morphology of the bottom of TiO nanotubes are explored. The results show the inner diameter of the bottom became larger with the temperature increasing due to the wall thickness of bottom of TiO nanotubes decreased and assisted by the increased fluorine content of the bottom, which is strong evidence for the mechanism proposed. What is more, the inner diameter of the bottom of THTNA can be manipulated via this novel mechanism. [ABSTRACT FROM AUTHOR]

Mass graphene sheets were obtained by a re-expansion and exfoliation method which uses the commercially available graphite intercalation compounds as the starting materials. The as-prepared samples have been characterized by scanning electronic microscopy, transmission electron microscope, atomic force microscope, Fourier transform infrared spectrometer spectroscopies, and Raman microscope. Using high resolution transmission electron microscopy on 60 samples, it was shown that the final samples exhibit 8 % monolayer, 19 % bilayer, and 77 % less than or equal to five layers, and the sheets are largely free of defects and chemical functional groups after thermal reduction. [ABSTRACT FROM AUTHOR]

The linear-stability analysis of thermocapillary flow in the annular immiscible two-layer system of 5cSt silicone oil and HT-70 with a radial temperature gradient was carried out. The annular two-layer system is heated at the outer cylindrical wall and cooled at the inner wall, the bottom and top surfaces are bounded by two rigid and heat-insulated walls. The influences of the liquid layer depth and radius ratio between the cold inner wall and the hot outer wall on stability are thoroughly investigated. The critical Marangoni number, critical wave number and critical phase velocity are obtained. In addition, the mode of bifurcation for the hydrothermal wave is predicted at different liquid layer depth, and the temperature disturbance pattern of hydrothermal wave at interface is also exhibited. [ABSTRACT FROM AUTHOR]

A loop heat pipe with flat evaporator (FLHP) is manufactured from copper, and filled with ultrapure water as the working fluid. The heat transfer characteristics have been studied experimentally. The gravity impacts the heat transfer characteristics of the FLHP in different orientations. Operation of the FLHP at orientations against the gravity which is the evaporator above the condenser leads to the higher temperature of the evaporator and the lower loop heat tranfer performance. At horizontal orientation with the evaporator above the compensation chamber (CC), the working fluid is difficult to reach the wick and has the highest temperature. With the increasing of the heat load upto more than 300 W, the loop thermal resistance decreases and approaches a minimum value of about 0.2 K/W at the vertical orientation helped by gravity. Experimental results show that the start-up with low power needs a temperature overshoot. Oscillations with high frequency (with periods on the order of seconds to minutes) and high amplitude (with temperature changes on the order of tens degree Kelvin) are observed. A model is developed, which shows the working fluid distributing in the evaporator wick may result such oscillations. In most cases, the highest amplitude in the loop is observed in the liquid line near CC, and the lowest amplitude is in the CC. [ABSTRACT FROM AUTHOR]

Two different dispersion methods were studied in order to obtain rhenium [188Re] sulfide suspension with different particle size distributions. The manufactured swirling device offers Suspension I with larger particles (55%>5 µm, 19%>10 µm). However, ultrasonication can only produce Suspension II with smaller particles (93%<5 µm, 0.3%>10 µm). Stability tests indicated that deposition appears after 6 and 15 minutes for Suspensions I and II, respectively. Radiochemical purity and particle size distribution did not change distinctively within 24 hours. So, both suspensions can be used in animal tests to find out the optimal particle size ranges for intra-articular injection. [ABSTRACT FROM AUTHOR]