Statistical analyses

  • 文章类型: Journal Article
    在哈尔施塔特时期,粘土船在社会活动中具有广泛的功能。除了食品储存和加工,它们被用于仪式目的和作为葬礼船只。本文介绍了来自西里西亚(波兰)下两个不同Hallstatt文化遗址的31个花瓶的考古和色谱研究结果。调查包括多马斯瓦夫公墓和Milejowice定居点的船只碎片。色谱分析的重点是脂肪酸和生物标志物,并有可能确定它们在使用过程中接触到的物质的最可能来源。c均值和层次聚类分析表明,坟墓容器与沉降陶瓷不同。因此,可以得出不同船只功能的结论。
    Clay vessels have a wide variety of functions in social activities in the Hallstatt period. In addition to food storage and processing, they were used for ritual purposes and as funerary vessels. The paper presents the results of archaeological and chromatographic studies of 31 vases from two different Hallstatt culture sites in lower Silesia (Poland). The investigations included vessels fragments from the Domasław cemetery and from the Milejowice settlement. The chromatographic analyses focused on fatty acids and biomarkers and made it possible to identify the most likely sources of substances they came into contact with during use. The c-means and hierarchical cluster analyses showed that grave vessels differed from settlement ceramics. Thus, conclusions on the diverse vessel functions could be made.
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  • 文章类型: Journal Article
    背景:随着血流限制在不同人群中的普及(例如,年轻人和老年人)和设置(例如,临床和运动康复),血流受限百分比的准确性变得至关重要。我们旨在比较年轻人中手动测量的动脉闭塞压(AOP),以了解下肢成分是否会影响实现AOP所需的压力。结果将阐明在实际和研究环境中用于估计AOP的已发布计算的充分性。
    方法:实施了一项观察性横断面研究设计,以检查下肢成分之间的关系,下肢周长,并测量AOP。
    方法:22名参与者(12名男性,26[4]y,1.74[0.07]m,73.2[12.5]kg)在确定AOP(以毫米波为单位)和下肢周长(以厘米为单位)之前,进行了全身双能X射线吸收扫描。仰卧位,在优势腿上手动充气10厘米宽的袖带,使其达到无法通过胫骨后动脉的多普勒超声检测到脉搏以确定AOP的程度.下肢成分(脂肪,肌肉,和骨量[克])是从双能X射线吸收扫描中获得的。
    结果:下肢肌肉质量与AOP呈中度负相关(r2=.433,β=-0.004),与下肢围呈中度正相关(r2=.497,β=0.001)。在所有测量中,下肢围与AOP的关系最弱(r2=.316,β=0.050)。
    结论:报道的下肢肌肉质量之间的关系,下肢周长,AOP表明,随着肌肉质量的增加,下肢周长也增加,但AOP下降。这意味着不应将肢体周长用作计算采样人群中AOP的主要度量。我们建议在所有运动方式中实施血流限制时单独测量AOP。
    BACKGROUND: As blood flow restriction gains popularity across different populations (eg, young and older adults) and settings (eg, clinical and sports rehabilitation), the accuracy of blood flow restricted percentage becomes crucial. We aimed to compare manually measured arterial occlusion pressure (AOP) among young adults to understand whether lower limb composition affects the pressure required to achieve AOP. The results will shed light on the adequacy of published calculations used to estimate AOP in practical and research settings.
    METHODS: An observational cross-sectional study design was implemented to examine the relationship between lower limb composition, lower limb circumference, and measured AOP.
    METHODS: Twenty-two participants (12 males, 26 [4] y, 1.74 [0.07] m, 73.2 [12.5] kg) underwent a whole-body Dual-energy X-ray Absorptiometry scan before AOP (in millimeters of mercury) and lower limb circumference (in centimeters) were determined. In a supine position, a 10-cm wide cuff was manually inflated on the dominant leg to the point where a pulse could no longer be detected by a Doppler ultrasound of the posterior tibial artery to determine AOP. Lower limb composition (fat, muscle, and bone mass [in grams]) was obtained from the Dual-energy X-ray Absorptiometry scan.
    RESULTS: Lower limb muscle mass had a moderate negative relationship with AOP (r2 = .433, β = -0.004) and a moderate positive relationship with lower limb circumference (r2 = .497, β = 0.001). Lower limb circumference had the weakest relationship with AOP (r2 = .316, β = 0.050) of all measures.
    CONCLUSIONS: The reported relationships between lower limb muscle mass, lower limb circumference, and AOP suggest that as muscle mass increases, lower limb circumference also increases, yet AOP decreases. This implies that limb circumference should not be used as the primary measure for calculating AOP within the sampled population. We recommend individually measuring AOP when implementing blood flow restriction in all exercise modalities.
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  • 文章类型: Journal Article
    鉴于没食子酸(GA)的高抗氧化能力,人们对快速发展很感兴趣,选择性,简单,以及易于从复杂样品中测定的分析方法。因此,本研究旨在开发一种基于超声辅助磁性离子液体的分散液体微萃取(UA-MIL-DLLME)方法,用于在分光光度检测之前从各种样品中提取GA。通过统计分析对方法的关键变量进行了优化。制备并测试了四种磁性液体(MIL)以提取在水溶液中形成的GA-Se复合物。实验研究和理论计算均表明,最适合相关配合物相分离的MIL是[P6,6,6,14][Mn(hfacac)3]。已开发的UA-MIL-DLLME方法具有较宽的线性范围(5-400ngmL-1),显著的增强因子(133),和低检测限(1.6ngmL-1)。此外,提取回收率高(97±1%),相对标准偏差低(1.9%)。UA-MIL-DLLME方法的提取时间为8分钟。通过重复性和再现性研究评估方法的精密度。最后,UA-MIL-DLLME方法已成功应用于使用参考方法从复杂样品中提取GA。
    Given the high antioxidant capacity of gallic acid (GA), there is a great deal of interest in the development of rapid, selective, simple, and easily accessible analytical methods for its determination from complex samples. Consequently, the present study aimed to develop an ultrasonic assisted magnetic ionic liquid-based dispersive liquid microextraction (UA-MIL-DLLME) method for the extraction of GA from various samples prior to its spectrophotometric detection. The method\'s key variables were optimized through statistical analysis. Four magnetic liquids (MILs) were prepared and tested to extract the GA-Se complex formed in aqueous solution. Both experimental studies and theoretical calculations demonstrated that the most suitable MIL for the phase separation of the relevant complex is [P6,6,6,14][Mn(hfacac)3]. The developed UA-MIL-DLLME method exhibited a wide linear range (5-400 ng mL-1), a remarkable enhancement factor (133), and a low limit of detection (1.6 ng mL-1). Additionally, high extraction recovery (97 ± 1%) with a low relative standard deviation (1.9%) was achieved. The extraction time for the UA-MIL-DLLME method was 8 min. The precision of the method was evaluated through repeatability and reproducibility studies. Finally, the UA-MIL-DLLME method was successfully applied to the extraction of the GA from complex samples using a reference method.
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  • 文章类型: Journal Article
    本文强调了pH或质子活性测量在环境研究中的关键作用,并强调了在处理pH数据时应用适当统计方法的重要性。这允许做出更明智的决策,以有效地管理环境数据,例如采矿受影响的水。同一系统的pH和{H+}显示出不同的分布,pH值主要显示正常或双峰分布,{H}显示对数正态分布。因此,是否使用pH或{H+}来计算用于进一步环境统计分析的集中趋势的平均值或测量是一个挑战。在这项研究中,应用不同的统计技术来了解来自四个不同矿区的pH和{H+}的分布,Metsämonttu在芬兰,FelsendomeRabenstein在德国,南非的Eastrand和Westrand矿山水处理厂。根据统计结果,如果分布是单峰的,则几何平均值可用于计算pH的平均值。对于多峰pH数据分布,峰识别方法可用于提取每个数据群体的平均值,并将其用于进一步的统计分析。
    This paper highlights the critical role of pH or proton activity measurements in environmental studies and emphasises the importance of applying proper statistical approaches when handling pH data. This allows for more informed decisions to effectively manage environmental data such as from mining influenced water. Both the pH and {H+} of the same system display different distributions, with pH mostly displaying a normal or bimodal distribution and {H+} showing a lognormal distribution. It is therefore a challenge of whether to use pH or {H+} to compute the mean or measures of central tendency for further environmental statistical analyses. In this study, different statistical techniques were applied to understand the distribution of pH and {H+} from four different mine sites, Metsämonttu in Finland, Felsendome Rabenstein in Germany, Eastrand and Westrand mine water treatment plants in South Africa. Based on the statistical results, the geometric mean can be used to calculate the average of pH if the distribution is unimodal. For a multimodal pH data distribution, peak identifying methods can be applied to extract the mean for each data population and use them for further statistical analyses.
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  • 文章类型: Journal Article
    背景:食管癌是一种生存率较低的恶性肿瘤。他汀类药物,常用的降脂作用,已经被认为具有针对各种癌症的潜在化学预防特性,包括食道癌.
    目的:本系统综述研究了他汀类药物摄入与食管癌的关系。
    方法:为了进行系统综述和荟萃分析,我们回顾了1980年至2023年6月在WebofScience(WOS)上发表的研究,Embase,MEDLINE/PubMed,Scopus,和Cochrane图书馆数据库根据PRISMA指南。数据提取,质量评估,使用预定义的方案进行统计分析.我们使用Stata统计软件进行了各种统计检验。在p<0.05时,统计显著性被认为是显著的。
    结果:收集并分析了21项研究。荟萃分析表明,与未接受他汀类药物组相比,接受他汀类药物治疗的食管癌患者的比值比(OR)为0.65(95%CI:0.57-0.75,p<0.001)。病例对照和队列研究的OR分别为0.67(95%CI:0.54-0.83,p<0.001)和0.62(95%CI:0.55-0.71,p<0.001),分别。根据Begg检验(p=0.966)和Egger检验(p=0.113),对他汀类药物摄入量与食管癌发病率之间关系的调查未发现任何发表偏倚的迹象。
    结论:结果显示,与未接受他汀类药物治疗的患者相比,接受他汀类药物治疗的患者发生食管癌的几率降低了35%。然而,需要进一步精心设计的前瞻性研究来验证这些发现,并了解他汀类药物预防食管癌的潜在机制.
    BACKGROUND: Esophageal cancer is a malignant tumor with a low survival rate. Statins, commonly prescribed for their lipid-lowering effects, have been suggested to possess potential chemopreventive properties against various cancers, including esophageal cancer.
    OBJECTIVE: This systematic review studied the association between statin intake and esophageal cancer.
    METHODS: To conduct this systematic review and meta-analysis, we reviewed studies published between 1980 and June 2023 in Web of Science (WOS), Embase, MEDLINE/PubMed, Scopus, and Cochrane Library databases according to the PRISMA guidelines. Data extraction, quality assessment, and statistical analyses were performed using predefined protocols. We used various statistical tests conducted by Stata statistical software. Statistical significance was considered significant at p < 0.05.
    RESULTS: Twenty-one studies were collected and analyzed. The meta-analysis demonstrated that the odds ratio (OR) of esophageal cancer in patients treated with statins was 0.65 (95% CI: 0.57-0.75, p < 0.001) compared to the non-receiving group. The ORs for case-control and cohort studies were 0.67 (95% CI:0.54-0.83, p < 0.001) and 0.62 (95% CI:0.55-0.71, p < 0.001), respectively. The investigation into the relationship between the statins intake and the incidence of esophageal cancer did not reveal any indication of publication bias according to both Begg\'s test (p = 0.966) and Egger\'s test (p = 0.113).
    CONCLUSIONS: The results revealed that the odds of esophageal cancer in patients treated with statins decreased by 35% compared to patients not treated with statins. However, further well-designed prospective studies are needed to validate these findings and understand the underlying mechanisms of statins in preventing esophageal cancer.
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  • 文章类型: Journal Article
    子宫肌瘤(UF)是子宫的非癌生长,影响美国超过2600万妇女的生计。虽然UF可能没有伴随症状,对于一些女性来说,它们的存在导致了手术治疗,这可能是一个艰难的决策过程。在线媒体的网络抓取用于识别寻找UF治疗方案的女性的信息寻求行为。我们综合数据来描述UF治疗的趋势,包括识别个人正在寻求的信息(需求)和作为资源公开提供的信息(供应)之间的差距,这有助于本研究创造“信息沙漠”一词。“我们进行统计分析以了解信息寻求行为,确定信息供给和信息需求之间的差距,并确定医生的治疗建议和患者的治疗决定之间的相关性,作为年龄的函数,症状,以及有关特定治疗类型的知识。
    Uterine fibroids (UF) are noncancerous growths of the uterus and impact the livelihood of over 26 million women in the United States. Although UF may not have accompanying symptoms, for some women their presence leads to surgical treatment, which can be a difficult decision-making process. Web-scraping of online media is used to identify information-seeking behavior of women searching for UF treatment options. We synthesize the data to describe trends in UF treatment, including the identification of gaps between the information individuals are seeking (demand) and information that is publicly available as a resource (supply), which contributes to this study\'s creation of the term \"information desert.\" We perform statistical analysis to understand information-seeking behavior, determine the gap between information supply and information demand, and determine the correlation between a doctor\'s treatment recommendation and a patient\'s treatment decision as a function of age, symptoms, and knowledge obtained about specific types of treatment.
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  • 文章类型: Journal Article
    随着阿尔茨海默病从中期到晚期的发展,对选择性抗胆碱能药的寻找源于不同的胆碱酯酶水平。在这项计算研究中,我们通过基于分子对接的虚拟筛选,研究了FDA批准的化合物和代谢物对乙酰胆碱酯酶(AChE)和丁酰胆碱酯酶(BChE)的选择性.使用本地开发的统计方法代码评估结果。AChE和BChE的对接预测选择性主要是活性位点体积差异和AChE活性位点峡谷底部入口较窄的结果。
    The search for selective anticholinergic agents stems from varying cholinesterase levels as Alzheimer\'s Disease progresses from the mid to late stage. In this computational study, we probed the selectivity of FDA-approved and metabolite compounds against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with molecular-docking-based virtual screening. The results were evaluated using locally developed codes for the statistical methods. The docking-predicted selectivity for AChE and BChE was predominantly the consequence of differences in the volume of the active site and the narrower entrance to the bottom of the active site gorge of AChE.
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  • 文章类型: Journal Article
    工业活动有可能用多种重金属(HM)污染土壤。在加纳,然而,对工业区土壤HM污染的评估仍然有限。因此,阿克拉工业区之一的HM土壤污染,加纳被评估。采集土壤样本并分析HMs,包括Fe,Zr,Zn,Ti,Sr,Rb,Mn,Pb,Cu,和Co,使用X射线荧光(XRF)。确定了HM地球化学阈值(GTT),以确定土壤HM污染水平并确定需要修复的区域。此外,进行了风险评估,以评估与这些金属相关的潜在生态和人类健康风险。铁的平均浓度,Zn,Rb,Sr,Zr,Ti,Mn,Co,Cu,土壤中的Pb分别为:27133.83、147.72、16.30、95.95、307.11、4663.66、289.85、418.54、44.97和112.88mg/kg,分别。一般来说,HMs的浓度随深度而降低,尽管一些下层表现出升高的HM水平。土壤污染水平被归类为低铁,Rb,Zr,Ti,Mn,Co,和铜;对Sr和Zn适中;对Pb相当。值得注意的是,研究区域的西北部显示出相当高的HM污染程度。虽然土壤中的HMs具有较低的生态风险,人类健康风险评估表明,Co,特别是在儿童中。土壤中HMs的存在被认为是源于自然地质现象和人类活动。包括工业运营,农业实践,填埋活动,和车辆排放。
    Industrial activities have the potential to pollute soils with a wide variety of heavy metals (HMs). In Ghana, however, assessment of HM pollution of soils in industrial areas remains limited. Accordingly, HM soil pollution in one of the industrial areas in Accra, Ghana was assessed. Soil samples were taken and analysed for HMs, including Fe, Zr, Zn, Ti, Sr, Rb, Mn, Pb, Cu, and Co, using X-Ray Fluorescence (XRF). HM geochemical threshold values (GTVs) were determined to establish soil HM pollution levels and identify areas needing remediation. Furthermore, risk assessments were conducted to evaluate the potential ecological and human health risks associated with these metals. The mean concentrations of Fe, Zn, Rb, Sr, Zr, Ti, Mn, Co, Cu, and Pb in the soils were: 27133.83, 147.72, 16.30, 95.95, 307.11, 4663.66, 289.85, 418.54, 44.97, and 112.88 mg/kg, respectively. Generally, the concentrations of HMs decreased with depth, although some lower layers exhibited elevated HM levels. Soil pollution levels were categorized as low for Fe, Rb, Zr, Ti, Mn, Co, and Cu; moderate for Sr and Zn; and considerable for Pb. Notably, the northwestern part of the study area displayed a considerable to very high degree of HM contamination. While HMs in the soils posed low ecological risk, the human health risk assessment indicated potential health effects from Co, particularly in children. The presence of HMs in the soils was noted to originate from both natural geological phenomena and human activities, including industrial operations, agricultural practices, landfill activities, and vehicular emissions.
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  • 文章类型: Journal Article
    蜂花粉是最重要的蜂产品之一。为了预测其化学成分和营养价值,植物来源的花粉起着至关重要的作用。这篇综述旨在收集世界各地收集的有关花粉植物来源的所有可用数据。由于大量的数据和变量非线性主成分分析(NLPCA),通过应用分类主成分分析(CATPCA),进行是为了试图确定样品之间的任何特异性和/或差异。此外,监测了一些植物科/属/种对蜜蜂的重要性。基于CATPCA结果,家族可以用于区分来自北美/南美的样品。此外,来自欧洲(土耳其和塞尔维亚)的一些样本的特征是存在一些特定的家族。属是区分巴西和澳大利亚不同地区样品的绝佳工具,亚洲和非洲。由于高度和特定的生物多样性,从索诺兰沙漠(美国)获得的花粉样品在分析过程中完全分离。本文首次尝试总结和分类有关蜂花粉植物学来源的大量数据。关键词蜜蜂采集花粉·植物来源·孢粉学分析·统计分析。
    Bee-collected pollen is one of the most important bee products. In order to predict its chemical composition and nutritional value botanical origin of pollen plays a crucial role. This review intended to collect all available data published about botanical origin of pollen collected all around the world. Due to enourmous amount of data and variables nonlinear principal component analysis (NLPCA), by applying Categorical Principal Component Analysis (CATPCA), was conducted in order to try to determine any specifity and/or differences among samples. Also, importance of some plant families/genera/species for bees was monitored. Based on CATPCA results families can serve in order to distinct samples from North/South America. Also, some samples from Europe (Turkey and Serbia) were characterized with presence of some specific families. Genera were excellent tool to distinguish samples from different parts of Brazil as well as Australia, Asia and Africa. Due to high and specific biodiversity pollen samples obtained from Sonoran desert (USA) completely were separated during analysis. This review presents the first attempt to summarize and classify a large number of data about botanical sources of bee-collected pollen.
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  • 文章类型: Journal Article
    超高性能混凝土(UHPC)是一种结合了高强度混凝土基体和纤维增强的水泥基复合材料。因其优异的机械性能和耐久性而脱颖而出,这种材料已被广泛认为是高度复杂的工程项目的可行选择。本文提出(i)对组成材料对抗压强度机械性能的影响进行综述,弯曲拉伸强度,和UHPC的弹性模量,以及(ii)基于已开发数据库的简化统计分析确定组成材料的最佳数量。数据搜索仅限于以2%的体积含量生产具有直钢纤维的UHPC的纸张。UHPC混合模型是基于组成材料与机械性能关系的图形分析提出的,旨在优化材料的各项力学性能。结果证明符合文献中的规格,水泥消耗量大,大量存在精细材料,和低的水粘合剂比。混合物之间确定的差异反映了组成材料如何独特地影响混凝土的每种机械性能。总的来说,精细材料被证明在增加UHPC的抗压强度和弯曲抗拉强度方面发挥着重要作用,而水和超增塑剂对材料的可加工性有影响。
    Ultra-high-performance concrete (UHPC) is a cementitious composite combining high-strength concrete matrix and fiber reinforcement. Standing out for its excellent mechanical properties and durability, this material has been widely recognized as a viable choice for highly complex engineering projects. This paper proposes (i) the review of the influence exerted by the constituent materials on the mechanical properties of compressive strength, flexural tensile strength, and elastic modulus of UHPC and (ii) the determination of optimal quantities of the constituent materials based on simplified statistical analyses of the developed database. The data search was restricted to papers that produced UHPC with straight steel fibers at a content of 2% by volume. UHPC mixture models were proposed based on graphical analyses of the relationship of constituent materials versus mechanical properties, aiming to optimize the material\'s performance for each mechanical property. The results proved to be in accordance with the specifications present in the literature, characterized by high cement consumption, significant presence of fine materials, and low water-to-binder ratio. The divergences identified between the mixtures reflect how the constituent materials uniquely impact each mechanical property of the concrete. In general, fine materials were shown to play a significant role in increasing the compressive strength and flexural tensile strength of UHPC, while water and superplasticizers stood out for their influence on the material\'s workability.
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