178 research outputs found
Hydrogen-bond-assisted isotactic-specific radical polymerization of N-vinyl-2-pyrrolidone with tartrate additives in toluene at low temperatures : high-resolution 1H NMR analysis
A diethyl L-tartrate (L-EtTar)-assisted radical polymerization of N-vinyl-2-pyrrolidone has been developed as the first reported example of the synthesis of isotactic-rich poly(N-vinyl-2-pyrrolidone) (PVP). The addition of L-EtTar in toluene at temperatures of –40°C and lower led to a significant increase in the polymer yield by one order of magnitude compared with the reaction in the absence of L-EtTar. Decreasing the polymerization temperature led to increases in the isotacticity of the PVP, with the mm triad reaching 66.4% at −93 °C. 1H NMR measurement at 920 MHz was conducted to establish a reliable strategy for quantifying the triad tacticities. High-temperature NMR measurements at 250 °C were performed using a specially-designed NMR probe, which led to dramatic narrowing of the 1H line width
カチク フンニョウ オ ゲンリョウ ト シタ バイオガスプラント カラ ハイシュツ サレル ハイキブツ ノ タイヒカ ニ カンスル キソテキ ケンキュウ
家畜糞尿からメタンガスを回収するバイオガスプラントは,すべての処理が密閉槽内で行われるため臭気対策の点においても有効な処理方式である。しかし,発酵前後に排出される大量の搾汁分離かすや汚泥の処理問題が残る。本研究は,これらの廃棄物の堆肥化を図るにあたり,まず,それぞれの廃棄物の特性を明らかにする目的で,総量10kg規模程度の基礎的試験を実施した。その結果,1)搾汁分離かすのみの調製では,調製後の温度上昇は大きいが乾燥しやすい特性を持つこと。2)搾汁分離かすに汚泥を混合することによって水分含有率が維持されること。3)汚泥の混合比率が高い場合は稲藁ないし米糠を加えることによって温度上昇が大きくなること,特に,4)稲藁を加えた場合は混合量が少量でも温度上昇は大きくなることを明らかにした。Bio-gasplant collects a methane gas from livestock excreta. This is a useful way of dealing with the bad smell because all treatment is carried out in closed tanks. But the treatment of digested sludge and other sludge discharged from the system becomes an issue. This study is an experiment in mixed composting of the digested sludge and other sludge. The purpose of this experiment is to grasp the essentials of the sludge for composting on a small scale ; 10kg approximately in total. The results show clearly 1) Only in digested sludge, the temperature of manure is high and it dries quickly;2) In case of other sludge mixed with digested sludge, the moisture of manure maintains a certain level ; 3) In case of higher portion digested sludge, the degree of temperature of the manure is raised by the addition of rice straw or rice bran and ; 4) even a small addition of rice straw on manure raises the degree of temperature of the manure
Identification of molecules associated with response to abatacept in patients with rheumatoid arthritis
LDL-Induced Impairment of Human Vascular Smooth Muscle Cells Repair Function Is Reversed by HMG-CoA Reductase Inhibition
Growing human atherosclerotic plaques show a progressive loss of vascular smooth muscle cells (VSMC) becoming soft and vulnerable. Lipid loaded-VSMC show impaired vascular repair function and motility due to changes in cytoskeleton proteins involved in cell-migration. Clinical benefits of statins reducing coronary events have been related to repopulation of vulnerable plaques with VSMC. Here, we investigated whether HMG-CoA reductase inhibition with rosuvastatin can reverse the effects induced by atherogenic concentrations of LDL either in the native (nLDL) form or modified by aggregation (agLDL) on human VSMC motility. Using a model of wound repair, we showed that treatment of human coronary VSMC with rosuvastatin significantly prevented (and reversed) the inhibitory effect of nLDL and agLDL in the repair of the cell depleted areas. In addition, rosuvastatin significantly abolished the agLDL-induced dephosphorylation of myosin regulatory light chain as demonstrated by 2DE-electrophoresis and mass spectrometry. Besides, confocal microscopy showed that rosuvastatin enhances actin-cytoskeleton reorganization during lipid-loaded-VSMC attachment and spreading. The effects of rosuvastatin on actin-cytoskeleton dynamics and cell migration were dependent on ROCK-signalling. Furthermore, rosuvastatin caused a significant increase in RhoA-GTP in the cytosol of VSMC. Taken together, our study demonstrated that inhibition of HMG-CoA reductase restores the migratory capacity and repair function of VSMC that is impaired by native and aggregated LDL. This mechanism may contribute to the stabilization of lipid-rich atherosclerotic plaques afforded by statins
The 2020 UV emitter roadmap
Solid state UV emitters have many advantages over conventional UV sources. The (Al,In,Ga)N material system is best suited to produce LEDs and laser diodes from 400 nm down to 210 nm—due to its large and tuneable direct band gap, n- and p-doping capability up to the largest bandgap material AlN and a growth and fabrication technology compatible with the current visible InGaN-based LED production. However AlGaN based UV-emitters still suffer from numerous challenges compared to their visible counterparts that become most obvious by consideration of their light output power, operation voltage and long term stability. Most of these challenges are related to the large bandgap of the materials. However, the development since the first realization of UV electroluminescence in the 1970s shows that an improvement in understanding and technology allows the performance of UV emitters to be pushed far beyond the current state. One example is the very recent realization of edge emitting laser diodes emitting in the UVC at 271.8 nm and in the UVB spectral range at 298 nm. This roadmap summarizes the current state of the art for the most important aspects of UV emitters, their challenges and provides an outlook for future developments
Guidelines for the management of biliary tract and ampullary carcinomas: surgical treatment
The only curative treatment in biliary tract cancer is surgical treatment. Therefore, the suitability of curative resection should be investigated in the first place. In the presence of metastasis to the liver, lung, peritoneum, or distant lymph nodes, curative resection is not suitable. No definite consensus has been reached on local extension factors and curability. Measures of hepatic functional reserve in the jaundiced liver include future liver remnant volume and the indocyanine green (ICG) clearance test. Preoperative portal vein embolization may be considered in patients in whom right hepatectomy or more, or hepatectomy with a resection rate exceeding 50%–60% is planned. Postoperative complications and surgery-related mortality may be reduced with the use of portal vein embolization. Although hepatectomy and/or pancreaticoduodenectomy are preferable for the curative resection of bile duct cancer, extrahepatic bile duct resection alone is also considered in patients for whom it is judged that curative resection would be achieved after a strict diagnosis of its local extension. Also, combined caudate lobe resection is recommended for hilar cholangiocarcinoma. Because the prognosis of patients treated with combined portal vein resection is significantly better than that of unresected patients, combined portal vein resection may be carried out. Prognostic factors after resection for bile duct cancer include positive surgical margins, especially in the ductal stump; lymph node metastasis; perineural invasion; and combined vascular resection due to portal vein and/or hepatic artery invasion. For patients with suspected gallbladder cancer, laparoscopic cholecystectomy is not recommended, and open cholecystectomy should be performed as a rule. When gallbladder cancer invading the subserosal layer or deeper has been detected after simple cholecystectomy, additional resection should be considered. Prognostic factors after resection for gallbladder cancer include the depth of mural invasion; lymph node metastasis; extramural extension, especially into the hepatoduodenal ligament; perineural invasion; and the degree of curability. Pancreaticoduodenectomy is indicated for ampullary carcinoma, and limited operation is also indicated for carcinoma in adenoma. The prognostic factors after resection for ampullary carcinoma include lymph node metastasis, pancreatic invasion, and perineural invasion
Association between age at disease onset of anti-neutrophil cytoplasmic antibody-associated vasculitis and clinical presentation and short-term outcomes
Objectives: ANCA-associated vasculitis (AAV) can affect all age groups. We aimed to show that differences in disease presentation and 6 month outcome between younger- A nd older-onset patients are still incompletely understood. Methods: We included patients enrolled in the Diagnostic and Classification Criteria for Primary Systemic Vasculitis (DCVAS) study between October 2010 and January 2017 with a diagnosis of AAV. We divided the population according to age at diagnosis: <65 years or ≥65 years. We adjusted associations for the type of AAV and the type of ANCA (anti-MPO, anti-PR3 or negative). Results: A total of 1338 patients with AAV were included: 66% had disease onset at <65 years of age [female 50%; mean age 48.4 years (s.d. 12.6)] and 34% had disease onset at ≥65 years [female 54%; mean age 73.6 years (s.d. 6)]. ANCA (MPO) positivity was more frequent in the older group (48% vs 27%; P = 0.001). Younger patients had higher rates of musculoskeletal, cutaneous and ENT manifestations compared with older patients. Systemic, neurologic,cardiovascular involvement and worsening renal function were more frequent in the older-onset group. Damage accrual, measured with the Vasculitis Damage Index (VDI), was significantly higher in older patients, 12% of whom had a 6 month VDI ≥5, compared with 7% of younger patients (P = 0.01). Older age was an independent risk factor for early death within 6 months from diagnosis [hazard ratio 2.06 (95% CI 1.07, 3.97); P = 0.03]. Conclusion: Within 6 months of diagnosis of AAV, patients >65 years of age display a different pattern of organ involvement and an increased risk of significant damage and mortality compared with younger patients
Interplay between actomyosin and E-cadherin dynamics regulates cell shape in the Drosophila embryonic epidermis
Precise regulation of cell shape is vital for building functional tissues. Here, we study the mechanisms which lead to the formation of highly elongated anisotropic epithelial cells in the Drosophila epidermis. We demonstrate that this cell shape is the result of two counteracting mechanisms at the cell surface which regulate the degree of elongation: actomyosin, which inhibits cell elongation downstream of RhoA signalling, and intercellular adhesion, modulated via clathrin-mediated endocytosis of E-cadherin, which promotes cell elongation downstream of the GTPase Arf1. We show that these two mechanisms do not act independently but are interconnected, with RhoA signalling reducing Arf1 recruitment to the plasma membrane. Additionally, cell adhesion itself regulates both mechanisms: p120-catenin, a regulator of intercellular adhesion, promotes the activity of both Arf1 and RhoA. Altogether, we uncover a complex network of interactions between cell-cell adhesion, the endocytic machinery, and the actomyosin cortex, and demonstrate how this network regulates cell shape in an epithelial tissue in vivo
Influence of lumbar kyphosis and back muscle strength on the symptoms of gastroesophageal reflux disease in middle-aged and elderly people
Association between blood glucose variability and coronary plaque instability in patients with acute coronary syndromes
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