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Hypertension is one of the strongest risk factors for cardiovascular diseases, cerebral stroke, and kidney failure. Lifestyle and nutrition are important factors that modulate blood pressure. Hypertension can be controlled by increasing physical activity, decreasing alcohol and sodium intake, and stopping tobacco smoking. Chronic kidney disease patients often have increased blood pressure, which indicates that kidney is one of the major organs responsible for blood pressure homeostasis. The decrease of renal sodium reabsorption and increase of diuresis induced by high potassium intake is critical for the blood pressure reduction. The beneficial effect of a high potassium diet on hypertension could be explained by decreased salt reabsorption by sodium-chloride cotransporter (NCC) in the distal convoluted tubule (DCT). In DCT cells, NCC activity is controlled by with-no-lysine kinases (WNKs) and its down-stream target kinases, Ste20-related proline-alanine-rich kinase (SPAK) and oxidative stress-responsive 1 (OSR1). The kinase activity of WNKs is inhibited by intracellular chloride ([Cl

Cytochrome P-450 (Cyp) epoxygenase-dependent metabolites of arachidonic acid (AA) have been shown to inhibit renal Na+transport, and inhibition of Cyp-epoxygenase is associated with salt-sensitive hypertension. We used the patch-clamp technique to examine whether Cyp-epoxygenase-dependent AA metabolites inhibited the basolateral 40-pS K+channel (Kir4.1/Kir5.1) in the distal convoluted tubule (DCT). Application of AA inhibited the basolateral 40-pS K+channel in the DCT. The inhibitory effect of AA on the 40-pS K+channel was specific because neither linoleic nor oleic acid was able to mimic the effect of AA on the K+channel. Inhibition of Cyp-monooxygenase with N-methylsulfonyl-12,12-dibromododec-11-enamide or inhibition of cyclooxygenase with indomethacin failed to abolish the inhibitory effect of AA on the 40-pS K+channel. However, the inhibition of Cyp-epoxygenase with N-methylsulfonyl-6-(propargyloxyphenyl)hexanamide abolished the effect of AA on the 40-pS K+channel in the DCT. Moreover, addition of either 11,12-epoxyeicosatrienoic acid (EET) or 14,15-EET also inhibited the 40-pS K+channel in the DCT. Whole cell recording demonstrated that application of AA decreased, whereas N-methylsulfonyl-6-(propargyloxyphenyl)hexanamide treatment increased, Ba2+-sensitive K+currents in the DCT. Finally, application of 14,15-EET but not AA was able to inhibit the basolateral 40-pS K+channel in the DCT of Cyp2c44−/−mice. We conclude that Cyp-epoxygenase-dependent AA metabolites inhibit the basolateral Kir4.1/Kir5.1 in the DCT and that Cyp2c44-epoxygenase plays a role in the regulation of the basolateral K+channel in the mouse DCT.

Purpose The purpose of this paper is to study the operation performance of the high-speed ramjet kinetic energy projectile using solid fuel ramjet as power plant that is a new short-range and small caliber projectile. Design/methodology/approach The numerical investigation on combustion characteristic of polyethylene in high-speed ramjet kinetic energy projectile is carried out in this paper. The flow characteristics’ differences are analyzed when ramjet works or do not work, and both the combustion characteristics and propulsive performance are analyzed when ramjet works. Findings The results show that with the increase of the abscissa x, the flame front is close to solid fuel surface at first and then keeps away from solid fuel surface. With the increase of the abscissa x, the temperature of solid fuel surface and regression rate of solid fuel continues to increase before re-attachment point and then decreases, which a maximum locate at the re-attachment point. Both the average temperature and the regression rate on the surface of the solid fuel tend to rise as the increase of inflow Mach number. As the inflow of Mach number increases, the mass flow rate of gaseous fuel increases. Practical implications The research results can provide useful database for the subsequent research on high-speed ramjet kinetic energy projectile. Originality/value This paper studies the operation characteristics of the ramjet projectile, especially the effect of the change of the flight velocity on the performance of high-speed ramjet projectile.

We report an all-fiberized chirped pulse amplification system without any bulk devices. The stretcher and compressor are chirped fiber Bragg gratings inscribed in a 6/125 μm single-mode fiber and a 30/250 μm large-mode-area fiber. The fabrication system of chirped fiber Bragg gratings was designed and built by ourselves. The width of the linear exposure spot was controlled according to the different fiber sizes to improve the fabrication quality, and the parameters of chirped fiber Bragg gratings were fine-tuned during the fabrication to achieve the overall system’s spectral matching. Two fiber circulators with the same fiber sizes as the chirped fiber Bragg gratings were employed to auxiliarily achieve the pulse stretching and compression. The dispersion accumulations provided by the stretcher and compressor are 129.8 ps and 90.8 ps. The power amplifiers were composed of the two-stage 10/130 μm fiber pre-amplifier and the 30/250 μm fiber main amplifier. The proposed chirped pulse amplification system with no spatial light is the true sense of an all-fiberized chirped pulse amplification structure and shows the main trend in development of ultrashort pulse fiber lasers.

Kir4.1 in the distal convoluted tubule plays a key role in sensing plasma potassium and in modulating the thiazide-sensitive sodium-chloride cotransporter (NCC). Here we tested whether dietary potassium intake modulates Kir4.1 and whether this is essential for mediating the effect of potassium diet on NCC. High potassium intake inhibited the basolateral 40 pS potassium channel (a Kir4.1/5.1 heterotetramer) in the distal convoluted tubule, decreased basolateral potassium conductance, and depolarized the distal convoluted tubule membrane in Kcnj10flox/flox mice, herein referred to as control mice. In contrast, low potassium intake activated Kir4.1, increased potassium currents, and hyperpolarized the distal convoluted tubule membrane. These effects of dietary potassium intake on the basolateral potassium conductance and membrane potential in the distal convoluted tubule were completely absent in inducible kidney-specific Kir4.1 knockout mice. Furthermore, high potassium intake decreased, whereas low potassium intake increased the abundance of NCC expression only in the control but not in kidney-specific Kir4.1 knockout mice. Renal clearance studies demonstrated that low potassium augmented, while high potassium diminished, hydrochlorothiazide-induced natriuresis in control mice. Disruption of Kir4.1 significantly increased basal urinary sodium excretion but it abolished the natriuretic effect of hydrochlorothiazide. Finally, hypokalemia and metabolic alkalosis in kidney-specific Kir4.1 knockout mice were exacerbated by potassium restriction and only partially corrected by a high-potassium diet. Thus, Kir4.1 plays an essential role in mediating the effect of dietary potassium intake on NCC activity and potassium homeostasis.

The mammalian distal convoluted tubule (DCT) makes an important contribution to potassium homeostasis by modulating NaCl transport. The thiazide-sensitive Na+/Cl− cotransporter (NCC) is activated by low potassium intake and by hypokalemia. Coupled with suppression of aldosterone secretion, activation of NCC helps to retain potassium by increasing electroneutral NaCl reabsorption, therefore reducing Na+/K+ exchange. Yet the mechanisms by which DCT cells sense plasma potassium concentration and transmit the information to the apical membrane are not clear. Here, we tested the hypothesis that the potassium channel Kir4.1 is the potassium sensor of DCT cells. We generated mice in which Kir4.1 could be deleted in the kidney after the mice are fully developed. Deletion of Kir4.1 in these mice led to moderate salt wasting, low BP, and profound potassium wasting. Basolateral membranes of DCT cells were depolarized, nearly devoid of conductive potassium transport, and unresponsive to plasma potassium concentration. Although renal WNK4 abundance increased after Kir4.1 deletion, NCC abundance and function decreased, suggesting that membrane depolarization uncouples WNK kinases from NCC. Together, these results indicate that Kir4.1 mediates potassium sensing by DCT cells and couples this signal to apical transport processes.

The city of Xi’an, Shaanxi, China, was founded over 3000 years ago. However, the city faces urban geological hazards with 14 parallel ground fissures covering a wide area of the municipal area. The ground fissures are not only hazardous to surface buildings, structures and underground pipes but also pose a major safety risk to the 15 metro lines under construction or under planning. Such challenges are unprecedented in the history of metro construction around the world. Research indicates that the ground fissures in Xi’an produce three-dimensional motion, among which the vertical displacement has the strongest effects on metro engineering. The results of large-scale physical model tests suggest that damages such as cracks in tunnel lining, failures of waterproofing and deformation of metro rail can be caused by the activities of ground fissures. To mitigate such risks, this paper proposes a series of engineering countermeasures such as enlargement of tunnel sections to maintain clearance, use of segmented tunnels, enhancement of tunnel lining, and use of multiple waterproofing measures. These countermeasures have been proven to be effective and reliable, based on the successful operation of the Xi’an Metro for the past 3 years.

With the development of smart city, the concept of smart development is integrated into the construction management, so as to promote the smart development of construction and improve the efficiency of construction management. This paper discusses the application prospect of GIS-BIM integration technology in construction schedule management, site material management and safety management of construction personnel. At the same time, it looks into the application trend of gis-bim integration technology and global wide area network, Internet of things, virtual reality and other emerging technologies in the integration of building construction management, so as to promote the intelligent and visual management development of gis-bim integration technology in building construction management.

Kir4.1/5.1 heterotetramer participates in generating the negative cell membrane potential in distal convoluted tubule (DCT) and plays a critical role in determining the activity of Na-Cl cotransporter (NCC). Kir5.1 contains a phosphothreonine motif at its COOH terminus (AA249–252). Coimmunoprecipitation showed that Nedd4-2 was associated with Kir5.1 in HEK293 cells cotransfected with Kir5.1 or Kir4.1/Kir5.1. GST pull-down further confirmed the association between Nedd4-2 and Kir5.1. Ubiquitination assay showed that Nedd4-2 increased the ubiquitination of Kir4.1/Kir5.1 heterotetramer in the cells cotransfected with Kir4.1/Kir5.1, but it has no effect on Kir4.1 or Kir5.1 alone. Patch-clamp and Western blot also demonstrated that coexpression of Nedd4-2 but not Nedd4-1 decreased K currents and Kir4.1 expression in the cells cotransfected with Kir4.1 and Kir5.1. In contrast, Nedd4-2 fails to inhibit Kir4.1 in the absence of Kir5.1 or in the cells transfected with the inactivated form of Nedd4-2 (Nedd4-2C821A). Moreover, the mutation of TPVT motif in the COOH terminus of Kir5.1 largely abolished the association of Nedd4-2 with Kir5.1 and abolished the inhibitory effect of Nedd4-2 on K currents in HEK293 cells transfected with Kir4.1 and Kir5.1 mutant (Kir5.1T249A). Finally, the basolateral K conductance in the DCT and Kir4.1 expression is significantly increased in the kidney-specific Nedd4-2 knockout or in Kir5.1 knockout mice in comparison to their corresponding wild-type littermates. We conclude that Nedd4-2 binds to Kir5.1 at the phosphothreonine motif of the COOH terminus, and the association of Nedd4-2 with Kir5.1 facilitates the ubiquitination of Kir4.1, thereby regulating its plasma expression in the DCT.

The copper activation mechanism of pyrite surface was simulated by density functional theory (DFT) method. It is shown that copper (Cu) can easily adsorb on pyrite surface, which causes the flotation of pyrite. The adsorbed Cu 3d orbital interacts with surface S 3p orbital forming covalent Cu-S bond. The charge of sulfur dimer increases and the adsorbed Cu is positively charged while the positive charge of surface Fe atom decreased, resulting in the surface capturing electrons from Cu.

With the development of fluorescent technology, the application area of fluorescent material is expanding, which includes the fields of traffic, national defence, architecture, detection, decoration etc. In the field of printing, whether in the value of utility or view and admire, fluorescent adds tremendous energies. However, a majority of fluorescent materials used nowadays contain radioelement, which will do harm to human health. This paper considers the needs of fluorescent map printing, according to the defects of traditional fluorescent material such as low brightness, short duration time, strong radioactivity, limitation to spot color printing etc. It improves the capability of long fluorescent lag material and makes red, blue, green and yellow long fluorescent lag materials. Meanwhile, it tests the influence of ink thickness, illumination time and granule size etc. on irradiance capability. The thicker the ink is, the longer of the lag time will be. The bigger the granule size is, the lag time will be. It also tests its radioactivity extent, which is in the safety range and reaches the standard of environmental protection. According to the special requirement of map printing, this paper brings forward the technique scheme of the application of long fluorescent lag ink in map printing,which realizes the color fluorescent map printing.

To evaluate the expression of proteasome β5 subunit in human atherosclerotic plaque.The specimens of carotid endarterectomy were collected from 16 carotid stenosis patients. For the case group, they were divided into 2 groups: plaque (group A) and areas adjacent to plaque (group B). And carotid endarterium was obtained from 6 patients undergoing aortic replacement surgery. Relatively normal arterial intima (subclavian arteryinnominate artery) was selected as the control group (group C). Content of proteasome β5 subunit was evaluated by hematoxylineosin (HE) staining, immunohistochemistry and Western blot.(1) In patients with diabetes, hyperlipidemia and probable smoking, proteasome β5 subunit was enhanced in all groups; (2) Proteasome β5 subunit was demonstrated in both cytoplasm and nucleus of vascular smooth muscle cells, but mainly confined to cytoplasm; (3)The positive expression rate of β5 was 9/16 in group A, 11/16 in group B and 6/6 in group C. There was significant divergence in the expression of β5 in different sample sub-groups: group A (atherosclerotic plaque)group B (areas adjacent to plaque)group C (control group).The expression of β5 decrease markedly in human atherosclerotic plaques.

To investigate the effects of Cox7a2 on the LH-induced testosterone production and the involved autophagy regulating signals in TM3 mouse Leydig cells.The Cox7a2-pEYFP-N1 fluorescent protein vector was constructed and transfected into TM3 mouse Leydig cells. The level of testosterone was determined by ELISA, and the effects of Cox7a2 on the expression of the steroidogenic acute regulatory protein (StAR) and the phosphorylation of the autophagy regulatory factor P70S6K were detected by Western blot.LH stimulation increased the StAR protein expression and testosterone production, while Cox7a2 decreased P70S6K phosphorylation, reduced StAR expression and consequently inhibited LH-induced testosterone biosynthesis in the TM3 Leydig cells.Cox7a2 inhibits testosterone production by decreasing the StAR protein expression, which might be at least in part related with the activation of autophagy in TM3 mouse Leydig cells.

To investigate the relationship between mine environment and hypertension in miners.1736 male miners who worked under the ground and 825 on the ground were recruited in this study. Prevalence of hypertension under the ground and on the ground miners was compared.Prevalence of hypertension of miners under the ground was 23.91% and on the ground was 15.52% (chi(2) = 23.56, P0.001). Compared to miners on the ground, the relative risk of hypertension under the ground workers was 1.71 (95%CI 1.38 - 2.13). Prevalence of hypertension was correlated to the years of ground working (chi(2) = 37.00, P0.001). The binary logistic regression showed significant relationship between mine environment and hypertension under the ground miners (OR = 1.05, 95%CI 1.02 - 1.08).The underground environment is an important risk factor hypertension to the miners.

Background There is evidence that the autonomic nervous system may be involved in the mechanism of focal atrial fibrillation (AF), so the present study investigated the effects of the parasympathetic nervous system on the occurrence of focal AF originating from the pulmonary veins (PVs). Methods and Results In 10 mongrel dogs, programmed stimulation and local burst stimulation (12.5 Hz, impulse duration 0.5 ms) were performed at each of the PVs. Pacing thresholds at different sites were determined and shown as a terraced distribution. The closer to the ostium of the PV, the lower was the pacing threshold (P

Objective Proteasome is a mutiple-unit protease working on non-lysosomal protein degradation in cells. Recent studies have illustrated its potential roles in the whole process of atherosclerosis including endothelial dysfunction, formation of foam cells, smooth muscle cell proliferation, and vascular remodeling. This research aims to evaluate the expression of the proteasome β5 subunit in atherosclerotic plaques from patients subjected to aortic replacement surgery. Methods We assigned the atherosclerotic plaque tissue, from carotid endarterectomy for carotid stenosis patients, as the case group (16 cases). According to different degrees of arterial stenosis, we divided the samples into the edge portion (stenosis>50%, A group) and the core portion (stenosis≤50%, B group). Carotid endarteriums were obtained from four patients undergoing Aortic replacement surgery, selected relatively normal arterial intima (Subclavian artery and Innominate artery) as the control group; Collected clinical data of patients, such as age, sex, smoking history, hypertension, diabetes, hyperlipidemia, and the biochemical indicators. A portion of the sample was fixed in 10% formalin, dehydrationed in gradient alcohol, Transparented in xylene, embedded in paraffin, sections were prepared for HE staining and immunohistochemical analysis. Another part of the tissue was frozen in liquid nitrogen, for extracting Total protein, and Western Blot analysis. Data are expressed as percentage or mean±SE for continuous variables and by percentage for qualitative variables. The proteasome β5 subunit activity variables were compared by use of the χ2 test. Statistical significance was assumed for p Results (1) The decrease in the level of β5 had something to do with the risks of diabetes, Hyperlipidemia and possibility of smoking in the patients we observed; (2) β5 was expressed in all samples, most of which accumulated in cytoplasm with few exceptions in nucleus; (3) There was significant divergence in the expression of β5 in different sub-groups of samples: A group (arterial stenosis>50%) Conclusion The expression of β5 was decreased in the atherosclerotic plaques of patients, implying it might play an important role in the progress of atherosclerosis.