Semi-periodic structures namely inclined wavy structures （IWS） are experimentally observed in compressible mixing layers at two convective Mach numbers （Mc = 0.11 and 0.47）. Flow structures are ...visualized by the laserinduced planar laser Mie scattering （PLMS） technique. Two methods are developed to investigate the spatial distribu- tion and geometry of IWS： （1） the dominant mode extrac- tion （DME） method, to extract the dominant modes of IWS from the streamwise gray-level fluctuation, and （2） the phase tracking （PT） method, to identify the shape of IWS. The re- sults suggest that pressure perturbations account for the for- marion of IWS in the initial mixing region and the joint effect of dilatation and coherent vortices enhances IWS in the well- developed region. The large transverse （cross-flow） scale of the IWS and their relation to coherent vortices （CV） indicate that the disturbance originated from CV in the mixing center propagates far into the free streams. The DME and the PT method are shown to be the effective tools to study the geometrical features of wavy structures in compressible shear flows.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background： Clarifying the mechanisms underlying vascular smooth muscle cell （VSMC） proliferation is important for the prevention and treatment of vascular remodeling and the reverse of hyperplastic ...lesions. Previous research has shown that the gaseous signaling molecule sulfur dioxide （SO2） inhibits VSMC proliferation, but the mechanism for the inhibition of the angiotensin Ⅱ （Angll）-induced VSMC proliferation by SO, has not been fully elucidated. This study was designed to investigate if SO2 inhibited VSMC proliferation in mice with hypertension induced by Angll. Methods： Thirty-six male C57 mice were randomly divided into control, Angll, and Angll ＋ SO2 groups. Mice in Angll group and Angl I ＋ SO2 group received a capsule-type Angll pump implanted under the skin of the back at a slow-release dose of 1000 ng-kg^-1min In addition, mice in Angll ＋ SO2 received intraperitoneal injections of SO., donor. Arterial blood pressure of tail artery was determined. The thickness of the aorta was measured by elastic fiber staining, and proliferating cell nuclear antigen （PCNA） and phosphorylated-extracellular signal-regulated kinase （P-ERK） were detected in aortic tissues. The concentration of SO~ in serum and aortic tissue homogenate supernatant was measured using high-performance liquid chromatography with fluorescence determination. In the in vio＇o study, VSMC of A7R5 cell lines was divided into six groups： control, Angll, Angll ＋ SO2 PD98059 （an inhibitor of ERK phosphorylation）, Angll ＋ PD98059, and Angll ＋ SO, ＋ PD98059. Expression of PCNA, ERK, and P-ERK was determined by Western blotting. Results： In animal experiment, compared with the control group, Angll markedly increased blood pressure （P 〈 0.01 ） and thickened the aortic wall in mice （P 〈 0.05） with an increase in the expression of PCNA （P 〈 0.05）. SO2 however, reduced the systemic hypertension and the wall thickness induced by AnglI （P 〈 0.05）. It inhibited the increased expression of PCNA and P-ERK induced by AnglI （P 〈 0.05）. In cell experiment, PD98059, an ERK phosphorylation inhibitor, blocked the inhibitory effect of SO, on VSMC proliferation （P 〈 0.05）. Conclusions： ERK signaling is involved in the mechanisms by which SO, inhibits VSMC proliferation in Angll-induced hypertensive mice via ERK signaling.
The aircraft target in the airport and its ground background are significant in military applications. In order to employthe algorithms for the detection, identification and dynamic monitoring, a ...software which can complete infrared radiation simulation of aircraft/ground object in airports under conditions of different seasons, different meteorological conditions, different periods and different detecting bands is needed to provide training samples. This paper utilizes OpenGL to construct a model of the aircraft target in the airport and the ground object in Visual Studio2010. Combined withthe theoryof heat transfer and infrared radiation, this study embeds the RadThermIR software used for thermal infrared analysis and proposes infrared image simulation. Then we calculate the infrared radiation field model of the aircraft and its ground object. Choosingimage gray similarity as the evaluation metric, the infrared image simulation precision of this method is over 80%. Experiment results indicate thatour proposed method can provide training samples with analysis data of rich infrared characteristics and featured knowledge for the automatic detection and identification of aircraft targets in the all-weather airport.
Aim： Iron dyshomeostasis is one of the primary causes of neuronal death in Alzheimer＇s disease （AD）. Huperzine A （HupA）, a natural inhibitor of acetylcholinesterase （ACHE）, is a licensed anti-AD drug ...in China and a nutraceutical in the United Sates. Here, we investigated the protective effects of HupA against iron overload-induced injury in neurons. Methods： Rat cortical neurons were treated with ferric ammonium citrate （FAC）, and cell viability was assessed with MTT assays. Reactive oxygen species （ROS） assays and adenosine triphosphate （ATP） assays were performed to assess mitochondrial function. The labile iron pool （LIP） level, cytosolic-aconitase （c-aconitase） activity and iron uptake protein expression were measured to determine iron metabolism changes. The modified EIIman＇s method was used to evaluate AChE activity. Results： HupA significantly attenuated the iron overload-induced decrease in neuronal cell viability. This neuroprotective effect of HupA occurred concurrently with a decrease in ROS and an increase in ATP. Moreover, HupA treatment significantly blocked the upregulation of the LIP level and other aberrant iron metabolism changes induced by iron overload. Additionally, another specific AChE inhibitor, donepezil （Don）, at a concentration that caused AChE inhibition equivalent to that of HupA negatively, influenced the aberrant changes in ROS, ATP or LIP that were induced by excessive iron. Conclusion： We provide the first demonstration of the protective effects of HupA against iron overload-induced neuronal damage. This beneficial role of HupA may be attributed to its attenuation of oxidative stress and mitochondrial dysfunction and elevation of LIP, and these effects are not associated with its AChE-inhibiting effect.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Pancreatic cancer is one of the most common malignanttumors and remains a treatment-refractory cancer with a poor prognosis. Currently, the diagnosis of pancreatic neoplasm depends mainly on imaging ...and which methods are conducive to detecting small lesions. Compared to the other techniques, magnetic resonance imaging(MRI) has irreplaceable advantages and can provide valuable information unattainable with other noninvasive or minimally invasive imaging techniques. Advances in MR hardware and pulse sequence design have particularly improved the quality and robustness of MRI of the pancreas. Diffusion MR imaging serves as one of the common functional MRI techniques and is the only technique that can be used to reflect the diffusion movement of water molecules in vivo. It is generally known that diffusion properties depend on the characterization of intrinsic features of tissue microdynamics and microstructure. With the improvement of the diffusion models, diffusion MR imaging techniques are increasingly varied, from the simplest and most commonly used technique to the more complex. In this review, the various diffusion MRI techniques for pancreatic cancer are discussed, including conventional diffusion weighted imaging(DWI), multi-b DWI based on intra-voxel incoherent motion theory, diffusion tensor imaging and diffusion kurtosis imaging. The principles, main parameters, advantages and limitations of these techniques, as well as future directions for pancreatic diffusion imaging are also discussed.
To study a new effective approach which repairs large defects of skin and soft tissue in neck and face.
This procedure accomplishes repetitive sub-platysmal expansion to form large musculocutaneous ...flap with underlying pedicel. The surgeon slides it toward neck and face to repair the defects of skin and soft tissue.
Eleven patients, who had such defects in neck, face, cheek, chin or submental skin and soft tissue, underwent this treatment. All the flaps survive with no complications of blood supply deficiency or necrosis. The short-term and long-term results are both satisfying.
This method, making repetitive sub-platysmal expansion to form musculocutaneous flap and then slide it toward neck/face to repair large defects of skin and soft tissue, proves to be safe and reliable. And appropriate cases and strict operations are important.
To determine the prevalence and determinants of folic acid (FA) supplementation in Chinese couples planning for pregnancy and in women during early pregnancy.
This was a cross-sectional study based ...on the Shanghai PreConception Cohort (SPCC) study. Data on FA supplementation and socio-demographic features were collected using questionnaires. Couples visiting clinics for pre-pregnancy examination and pregnant women at < 14 gestational weeks were recruited in Shanghai, China, between March 2016 and September 2018.
Among the pregnancy planners, 42.4% (4,710/11,099) women and 17.1% (1,377/8,045) men used FA supplements, while 93.4% (14,585/15,615) of the pregnant women used FA supplements. FA supplement use was higher in female pregnancy planners who were older (RR: 1.13, 95% CI: 1.08–1.18), had higher education (RR: 1.71, 95% CI: 1.53–1.92), and were residing in urban districts (RR: 1.06, 95% CI: 1.01–1.11) of FA supplementation; female pregnancy planners with alcohol consumption (RR: 0.95, 95% CI: 0.90–0.99) had lower odds of FA supplementation. In early pregnancy, women with higher educational level (RR: 1.04, 95% CI: 1.03–1.06), who underwent pre-pregnancy examination (RR: 1.02, 95% CI: 1.01–1.03) had higher odds of using an FA supplement; older aged (RR: 0.99, 95% CI: 0.98–0.99), and multigravida (RR: 0.97, 95% CI: 0.96–0.98) had lower odds of FA supplementation.
Although the majority of pregnant women took FA supplements, more than half of the women planning for pregnancy did not. Urgent strategies are needed to improve pre-conception FA supplementation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background Multimorbidity have become a major character in the course of chronic diseases that brings a challenge for public health development in China. The development of multimorbidity research in ...China is in an early stage with fewer literature, and there is a lack of systematic and comprehensive literature analysis. Objective To conduct a bibliometric and visual analysis of research hotspots and evolutionary trends in the field of multimorbidity in China, grasp the research frontiers and development directions in the field, thereby providing a reference for future research directions. Methods CNKI (Chinese data source) and WOS (foreign data source) were searched for the literature in the field of multimorbidity researches published by Chinese researchers from 2002 to 2022. CiteSpace software was used to analyze the spatial and temporal distribution of multimorbidity and explore the research hotspots and evolutionary trends in the field of multimorbidity by plotting the collaboration network map of instit
Intestinal stem cells are regulated by the intestinal nervous system, and both of them are closely related to intestinal inflammation. Relevant studies have shown the existence of intestinal nerve ...dysfunction in intestinal inflammation. By summarizing the relationship among intestinal stem cells, intestinal nervous system and intestinal inflammation, this paper discusses that intestinal nervous system injury related to intestinal inflammation may be the basis for persistent alteration of intestinal function, while enteric neurons provide feasible targets for improving intestinal nerve dysfunction in inflammatory bowel diseases, so as to apply various types of stem cells to the improvement of intestinal nerve dysfunction in intestinal inflammation.
Background： Fetal brain development is a complicated process that continues throughout pregnancy. Fetal sulcus development has typical morphological features. Assessment of fetal sulcus development ...to understand the cortical maturation and development by prenatal ultrasound has become widespread. This study aimed to explore a reliable method to assess cortical sulcus and to describe the normal sonographic features of cortical sulcus development in the human fetus between 18 and 41 weeks of gestation. Methods： A cross-sectional study was designed to examine the fetal cortical sulcus development at 18-41 weeks of gestation. Ultrasound was used to examine the insula, sylvian fissure （SF）, parieto-occipital fissure （POF）, and calcarine fissure （CF）. Bland-Altman plots were used for assessing the concordance, and the intraclass correlation coefficient was used for assessing the reliability. Results： SF images were successfully obtained in 100% of participants at 22 weeks of gestation, while the POF images and CF images could be obtained in 100% at 23 weeks of gestation and 24 weeks of gestation, respectively. The SF width, temporal lobe depth, POF depth, and the CF depth increased with the developed gestation. The width of uncovered insula and the POF angle decreased with the developed gestation. By 23 weeks of gestation, the insula was beginning to be covered. Moreover, it completed at 35 weeks of gestation. The intra- and inter-observer agreements showed consistent reproducibility. Conclusions： This study defined standard views of the fetal sulcus as well as the normal reference ranges of these sulcus measurements between 18 and 41 weeks of gestation. Such ultrasonographic measurements could be used to identil fetuses at risk of fetal neurological structural disorders.
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