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In this study, natural convection flow in a porous cavity with sinusoidal temperature distribution has been analyzed by a new double multi relaxation time (MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9 lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9 have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement with the previous works, thus confirming the reliability the new numerical method proposed in this paper. It is indicated that the heat transfer rate increases at increasing Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and phase deviation. However, the most sensitive parameter is the Rayleigh number. The maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on the heat transfer rate increases at increasing Rayleigh number, yielding a maximum enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and Ra=$10^5$, respectively.  相似文献   
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Portilla-Fernández  Eliana  Hwang  Shih-Jen  Wilson  Rory  Maddock  Jane  Hill  W. David  Teumer  Alexander  Mishra  Pashupati P.  Brody  Jennifer A.  Joehanes  Roby  Ligthart  Symen  Ghanbari  Mohsen  Kavousi  Maryam  Roks  Anton J. M.  Danser  A. H. Jan  Levy  Daniel  Peters  Annette  Ghasemi  Sahar  Schminke  Ulf  Dörr  Marcus  Grabe  Hans J.  Lehtimäki  Terho  Kähönen  Mika  Hurme  Mikko A.  Bartz  Traci M.  Sotoodehnia  Nona  Bis  Joshua C.  Thiery  Joachim  Koenig  Wolfgang  Ong  Ken K.  Bell  Jordana T.  Meisinger  Christine  Wardlaw  Joanna M.  Starr  John M.  Seissler  Jochen  Then  Cornelia  Rathmann  Wolfgang  Ikram  M. Arfan  Psaty  Bruce M.  Raitakari  Olli T.  Völzke  Henry  Deary  Ian J.  Wong  Andrew  Waldenberger  Melanie  O’Donnell  Christopher J.  Dehghan  Abbas 《European journal of epidemiology》2021,36(11):1143-1155

Common carotid intima-media thickness (cIMT) is an index of subclinical atherosclerosis that is associated with ischemic stroke and coronary artery disease (CAD). We undertook a cross-sectional epigenome-wide association study (EWAS) of measures of cIMT in 6400 individuals. Mendelian randomization analysis was applied to investigate the potential causal role of DNA methylation in the link between atherosclerotic cardiovascular risk factors and cIMT or clinical cardiovascular disease. The CpG site cg05575921 was associated with cIMT (beta?=??0.0264, p value?=?3.5?×?10–8) in the discovery panel and was replicated in replication panel (beta?=??0.07, p value?=?0.005). This CpG is located at chr5:81649347 in the intron 3 of the aryl hydrocarbon receptor repressor gene (AHRR). Our results indicate that DNA methylation at cg05575921 might be in the pathway between smoking, cIMT and stroke. Moreover, in a region-based analysis, 34 differentially methylated regions (DMRs) were identified of which a DMR upstream of ALOX12 showed the strongest association with cIMT (p value?=?1.4?×?10–13). In conclusion, our study suggests that DNA methylation may play a role in the link between cardiovascular risk factors, cIMT and clinical cardiovascular disease.

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The1H-NMR signals of 2-cephems and 3-cephems have been assigned and the Nuclear Overhauser Effect (NOE) study of these compounds was undertaken.  相似文献   
15.
An investigation was undertaken to determine the toxicity of an intravitreal injection of a novel peptide drug, Shiva-1, in rabbits. The drug, a synthetic peptide modeled after lytic peptides secreted by certain insects, has antiproliferative and antibacterial properties. Initial in vitro experiments showed that the drug, at a concentration of 100 M, was toxic to both Y-79 retinoblastoma cells and human retinal pigment epithelial cells. A wide range of doses (6–1200 g) was injected into the rabbit vitreous in an attempt to determine the maximum tolerated dose. Retinal toxicity was evaluated clinically, by electroretinography, and by light microscopy. Some localized toxicity was evident at 200 g; all doses of 240 g and above were toxic. While the drug appears to exhibit a narrow range between effective and toxic doses, the results suggest that this and other peptides of similar design merit further investigation for the treatment of proliferative and infectious diseases of the eye.Supported in part by U.S. Public Health Service grants EY07541 and EY02377 from the National Eye Institute, the National Institutes of Health Services, Bethesda, MD, USA  相似文献   
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目的:牙周疾病非常普遍,尽管有各种特定的治疗方法,但我们始终面临治疗方法有限的问题。考虑到世界组织十分关注传统医学在医疗服务中的发展和应用,我们在一直考察研究伊朗传统医学中药物对牙周疾病的治疗作用。方法:此项研究是一个对有关方面书籍的综合论述,伊朗传统医学内容是经过对重量级作者如Avicenna和Alzahrawy所著的有价值的书籍修订,收集了各医学院校馆藏图书和医药公司的有关信息编辑而成,因为在伊朗传统医学中牙周疾病分成不同目类,对有关药物的研究也被分成8个大组63个题目。(1)缓解牙龈肿胀药物(2)治疗牙龈恶化药物(3)治疗口疮腐烂药物(4)治疗牙龈肥大药物(5)利于伤口康复药物(6)利于牙龈加固的药物(7)阻止牙龈出血的药物(8)防止牙齿松动药物。结果结论:伊朗传统医学在准确的观察和实践的基础上来描述和治疗牙周疾病的。在制药学、有效治疗方面、科学研究手段等领域,伊朗传统医学在以下几个方面可作为现代制药研究的重要资源:(1)纯天然资源(2)容易获得(3)相对比较安全。  相似文献   
18.
Patients with chronic diseases are severely affected by acute coronavirus syndrome. In this regard, patients with beta thalassemia intermedia and diabetes mellitus (DM) are also at high risk for coronavirus‐induced respiratory failure. The present study aimed to report a case with COVID‐19 with a history of chronic diseases, beta thalassemia intermedia, and DM. A 25‐year‐old man visited with complaints of severe shortness of breath, fever, cough without sputum, and tachypnea and admitted to the Intensive Care Unit. The patient had a history of DM, beta thalassemia intermedia, and pervious history of the splenectomy. In peripheral complete blood count (CBC diff), the number of white blood cell count was 41,100 of which 38.6% were lymphocytes. We measured the normal platelet count, hemoglobin level (9.4), and red blood cell count (3.56). ESR was 97, CRP = pos+++ and PCR was positive. The high‐resolution lung CT indicated ground glass opacities in peripheral areas. The patient underwent 13 days of oxygen therapy with reservoir bag‐mask, non‐invasive ventilation, nasal oxygen, and pharmacological treatment with IFN‐β1a and meropenem, and finally discharged with an improvement of the clinical condition. Timely initiation of treatment is very important and significant for patients with beta thalassemia intermedia with COVID‐19, especially despite the underlying disease of DM. According to the present report, the use of IFN‐β1a was effective as a treatment option for COVID‐19.  相似文献   
19.
Phage therapy is a promising biocontrol management on plant diseases caused by bacterial pathogens due to its specificity, efficiency and environmental friendliness. The emergence of natural phage-resistant bacteria hinders the application of phage therapy. Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of the devastating bacterial leaf blight disease of rice. Here, we obtained a spontaneous mutant C2R of an Xoo strain C2 showing strong resistance to the lytic phage X2. Analysis of the C2R genome found that the CDS2289 gene encoding glycosyltransferase acquired a frameshift mutation at the 180th nucleotide site, which also leads to a premature stop mutation at the 142nd amino acid. This mutation confers the inhibition of phage adsorption through the changes in lipopolysaccharide production and structure and bacterial surface morphology. Interestingly, glycosyltransferase-deficient C2R and an insertional mutant k2289 also showed reduced virulence, suggesting the trade-off costs of phage resistance. In summary, this study highlights the role of glycosyltransferase in interactions among pathogenic bacteria, phages and plant hosts, which provide insights into balanced coevolution from environmental perspectives.  相似文献   
20.
The gut microbiota is closely related to good health; thus, there have been extensive efforts dedicated to improving health by controlling the gut microbial environment. Probiotics and prebiotics are being developed to support a healthier intestinal environment. However, much work remains to be performed to provide effective solutions to overcome individual differences in the gut microbial community. This study examined the importance of nutrients, other than dietary fiber, on the survival of gut bacteria in high-health-conscious populations. We found that vitamin B1, which is an essential nutrient for humans, had a significant effect on the survival and competition of bacteria in the symbiotic gut microbiota. In particular, sufficient dietary vitamin B1 intake affects the relative abundance of Ruminococcaceae, and these bacteria have proven to require dietary vitamin B1 because they lack the de novo vitamin B1 synthetic pathway. Moreover, we demonstrated that vitamin B1 is involved in the production of butyrate, along with the amount of acetate in the intestinal environment. We established the causality of possible associations and obtained mechanical insight, through in vivo murine experiments and in silico pathway analyses. These findings serve as a reference to support the development of methods to establish optimal intestinal environment conditions for healthy lifestyles.  相似文献   
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