CFG

CFG
  • 文章类型: Journal Article
    这篇综述文章介绍了目前使用和提出的制造涡轮发动机圆盘杉木树槽的方法。飞机的生产,包括在与新冠肺炎大流行或东欧战争相关的全球经济危机重叠时期的飞机发动机,需要对不断变化的乘客和货物数量做出快速反应。同样,航空业必须适应这些条件,因此,利用灵活的生产方法,允许快速改变给定零件的设计或类型。由于最关键的航空发动机零件不断采用新材料,并且必须遵守环境法规,有必要寻找制造这些零件的新方法,包括杉木树插槽。作为目前使用的昂贵和能源密集型拉削的替代品,许多制造商尝试实施蠕变进给磨削CFG或轮廓铣削。然而,其他制造方法,到目前为止,很少用于关键的机器零件,如电火花线切割,ECDM或AWJ,在航空业中越来越受欢迎。本文介绍了这些方法在制造杉木树槽的背景下的优点和缺点。
    This review article presents a summary of currently used and proposed methods of manufacturing fir tree slots of discs in turbine engines. The production of aircraft, including aircraft engines during times of overlapping global economic crises related to the COVID-19 pandemic or the war in Eastern Europe requires a quick response to the changing numbers of passengers and cargo. Similarly, the aviation industry must adapt to these conditions, and thus utilize flexible production methods allowing for a quick change in the design or type of a given part. Due to the constant adoption of new materials for the most critical aero engine parts and the necessity of complying with environmental regulations, it is necessary to search for new methods of manufacturing these parts, including fir tree slots. As an alternative to currently used expensive and energy-intensive broaching, many manufacturers try to implement creep feed grinding CFG or contour milling. However, other manufacturing methods, thus far rarely used for crucial machine parts such as WEDM, ECDM or AWJ, are gaining more and more popularity in the aviation industry. This article presents the advantages and shortcomings of these methods in the context of manufacturing fir tree slots.
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  • 文章类型: Journal Article
    背景:遵循加拿大食品指南(CFG)的建议应确保足够的营养素摄入量。老年人对某些营养素和营养密度的需求增加;遵守CFG建议可以在多大程度上帮助减少营养摄入不足尚不清楚。
    目的:我们的目的是评估2015年加拿大社区健康调查(CCHS)-营养中65岁及以上成年人对健康食物选择的CFG建议的依从性与关键营养素摄入量之间的关系。
    方法:对2015年CCHS4,093名老年人的营养数据进行二次分析(平均年龄,73.6年,54%女性)。使用面试官管理的24小时饮食回忆来测量饮食摄入量,其中包括一个子样本中的一个重复(42%)。国家癌症研究所多变量方法用于估计通常(即,长期)饮食摄入量。使用健康饮食指数(HEFI)-2019评分衡量对CFG建议的依从性。简单的线性和逻辑回归模型估计了HEFI-2019评分增加对常规营养素摄入量和营养素摄入量不足的患病率的影响(即,低于估计的平均需求),分别。
    结果:与HEFI-2019评分中位数(46.4/80分)摄入不足的患病率相比,较高的HEFI-2019(+11分)与镁摄入不足的患病率降低有关,维生素B6和蛋白质(-19.8%[95CI:-30.8,-8.9],-12.7%[95CI:-22.5,-3.0],和-4.7%[95CI:-9.4,-0.1],分别)。相比之下,较高HEFI-2019评分的数据与叶酸摄入不足的患病率增加相符,维生素D,和钙(4.0%[95CI:-8.4,16.3],2.6%[95CI:1.1,4.0],和2.3%[95CI:-3.0,7.5],分别)。
    结论:根据2015年加拿大老年人的饮食摄入量,增加对CFG健康食物选择建议的遵守程度可能会减少除叶酸外的大多数关键营养素的营养摄入不足,维生素D和钙。
    Following Canada\'s food guide (CFG) recommendations should ensure adequate nutrient intakes. Older adults have increased needs for certain nutrients and nutrient density; the extent to which adherence to CFG recommendations can help reduce inadequate nutrient intakes is unknown.
    We aimed to assess the relationship between adherence to CFG recommendations on healthy food choices and intake of key nutrients in adults 65 y and older from the Canadian Community Health Survey 2015 - Nutrition.
    Secondary analysis of data from 4093 older adults of the Canadian Community Health Survey 2015 - Nutrition (mean age, 73.6 y, 54% females). Dietary intakes were measured using an interviewer-administered 24-h dietary recall, including 1 repeat in a subsample (42%). The National Cancer Institute multivariate method was used to estimate usual (i.e., long-term) dietary intakes. Adherence to CFG recommendations was measured using the Healthy Eating Food Index (HEFI)-2019 score. Simple linear and logistic regression models estimated the effect of increased HEFI-2019 score on usual nutrient intakes and the prevalence of inadequate nutrient intakes (i.e., below the estimated average requirements), respectively.
    Compared with the prevalence of inadequate intakes at median HEFI-2019 score (46.4/80 points), a higher HEFI-2019 (+11 points) was associated with reductions in the prevalence of inadequate intakes of magnesium, vitamin B6 and protein [-19.8% (95% confidence interval (CI): -30.8, -8.9), -12.7% (95% CI: -22.5, -3.0), and -4.7% (95% CI: -9.4, -0.1), respectively]. In contrast, data for higher HEFI-2019 scores were compatible with increased prevalence of inadequate intakes of folate, vitamin D, and calcium [4.0% (95% CI: -8.4, 16.3), 2.6% (95% CI: 1.1, 4.0), and 2.3% (95% CI: -3.0, 7.5), respectively].
    Based on dietary intakes of Canadian older adults in 2015, increasing the degree of adherence to CFG recommendations on healthy food choices may reduce nutrient intake inadequacy for most key nutrients except folate, vitamin D, and calcium.
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  • 文章类型: Journal Article
    RNA分子中准确的“碱基配对”,这导致了RNA二级结构的预测,对于解释未知的生物操作至关重要。最近,COVID-19,一种广泛传播的疾病,造成了很多人死亡,以前所未有的方式影响人类。SARS-CoV-2是一种单链RNA病毒,显示了分析这些分子及其结构的重要性。本文旨在在预测特定RNA结构的方向上创建一个开创性的框架,利用句法模式识别。拟议的框架,Know+,解决了预测H型伪结的问题,包括凸起和内部回路,通过展示上下文无关语法(CFG)的力量。我们将语法的优势与最大碱基配对和最小自由能相结合,以高性能的方式解决这个模糊的任务。具体来说,我们提出的方法,Know+,在核心茎预测的准确性方面优于最先进的框架。此外,它在小序列中表现得更准确,在大序列中表现出相当的准确率,而与知名平台相比,它需要的执行时间更短。Knoto+源代码和实现详细信息作为GitHub上的公共存储库提供。
    The accurate \"base pairing\" in RNA molecules, which leads to the prediction of RNA secondary structures, is crucial in order to explain unknown biological operations. Recently, COVID-19, a widespread disease, has caused many deaths, affecting humanity in an unprecedented way. SARS-CoV-2, a single-stranded RNA virus, has shown the significance of analyzing these molecules and their structures. This paper aims to create a pioneering framework in the direction of predicting specific RNA structures, leveraging syntactic pattern recognition. The proposed framework, Knotify+, addresses the problem of predicting H-type pseudoknots, including bulges and internal loops, by featuring the power of context-free grammar (CFG). We combine the grammar\'s advantages with maximum base pairing and minimum free energy to tackle this ambiguous task in a performant way. Specifically, our proposed methodology, Knotify+, outperforms state-of-the-art frameworks with regards to its accuracy in core stems prediction. Additionally, it performs more accurately in small sequences and presents a comparable accuracy rate in larger ones, while it requires a smaller execution time compared to well-known platforms. The Knotify+ source code and implementation details are available as a public repository on GitHub.
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  • 文章类型: Journal Article
    背景:加拿大的《食品指南》(CFG)在2019年进行了重大修订,但对健康食品选择建议的遵守程度如何降低心血管疾病(CVD)的风险尚不清楚。
    目的:这项研究的目的是研究对2019年CFG关于健康食品选择的建议的更大依从性如何影响心血管事件的风险。
    方法:参与者是没有CVD病史的成人样本,糖尿病,或来自英国生物银行前瞻性队列研究的癌症。通常的饮食摄入量是通过使用国家癌症研究所多变量方法对重复的基于网络的24小时饮食回顾数据进行建模来估计的。使用健康饮食指数(HEFI)-2019评估了对CFG关于健康食品选择的关键建议的遵守情况,该指数最高为80分。CVD结局是致命和非致命心肌梗死和缺血性卒中的复合结局。通过逆概率加权调整的Cox回归模型用于估计CVD风险。反事实模型用于解释HEFI-2019评分假设变化的风险。
    结果:共有136,698名参与者符合资格标准(55%为女性;平均年龄:57.2岁;范围:40-75岁)。在11年的随访期间,有2843例心血管事件.与HEFI-2019评分无变化相比,将所有参与者的HEFI-2019评分提高至评分分布的第90百分位数(58.1分),假设可将CVD风险降低24%(RR:0.76;95%CI:0.58,0.94;绝对风险差异:-0.58%).
    结论:这些结果表明,更坚持2019年CFG关于健康食物选择的建议可降低中老年人患CVD的风险。
    Canada\'s Food Guide (CFG) was profoundly revised in 2019, but the extent to which adherence to recommendations on healthy food choices reduces the risk of cardiovascular disease (CVD) is unknown.
    The aim of this study was to examine how greater adherence to the 2019 CFG\'s recommendations on healthy food choices influences the risk of incident CVD.
    Participants were a sample of adults without history of CVD, diabetes, or cancer from the UK Biobank prospective cohort study. Usual dietary intakes were estimated by modeling data from repeated Web-based 24-h dietary recalls using the National Cancer Institute multivariate method. Adherence to key CFG recommendations on healthy food choices was assessed using the Healthy Eating Food Index (HEFI)-2019, which has a maximum of 80 points. The CVD outcome was a composite of fatal and nonfatal myocardial infarction and ischemic stroke. Cox regression models adjusted via inverse probability weighting were used to estimate CVD risks. Counterfactual models were used to interpret risks of hypothetical changes in the HEFI-2019 score.
    A total of 136,698 participants met the eligibility criteria (55% females; mean age: 57.2 y; range: 40-75 y). During the 11-y follow-up, there were 2843 cases of incident CVD. Compared with no change in the HEFI-2019 score, increasing the HEFI-2019 score of all participants to the 90th percentile of the score distribution (58.1 points) hypothetically reduced the risk of CVD by 24% (RR: 0.76; 95% CI: 0.58, 0.94; absolute risk difference: -0.58%).
    These results suggest that greater adherence to the 2019 CFG recommendations on healthy food choices reduces the 11-y risk of CVD in middle-aged and older adults.
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