multivariate analysis

多变量分析
  • 文章类型: Journal Article
    有效的废水管理在经历水资源短缺和环境压力的地区至关重要。比如污染和气候变化。优化处理工艺对于实现环境可持续性至关重要。这项研究旨在强调有效的废水管理策略的重要性,特别是在水资源短缺的地区。我们的目标是确定影响治疗过程的关键因素。因此,我们使用多元统计方法评估物理化学参数之间的关联,包括主成分分析(PCA)和分层上升分类(HAC)。我们的发现根据有机污染水平将每月水样分为三组:第一组(7月,August,和9月)的特点是氧合水平高,有机污染明显低,指示最佳系统运行。第二组(4月,十月,十一月,和12月)表现出低氧合和低有机污染,促进污泥沉降和减少污染物。第三组(1月,二月,March,May,和6月)显示出显著的高有机污染和低氧合,这对应于不利的环境条件。我们的研究证明了多元统计方法在优化废水处理过程中的有效性,为环境可持续性和水资源管理提供重要见解。
    Effective wastewater management is crucial in regions experiencing water scarcity and environmental stressors, such as pollution and climate change. Optimizing treatment processes is essential for achieving environmental sustainability. This study aims to highlight the importance of effective wastewater management strategies, particularly in regions facing water scarcity. Our objective was to identify key factors influencing the treatment process. Therefore, we evaluated associations between physicochemical parameters using multivariate statistical methods, including Principal Component Analysis (PCA) and Hierarchical Ascendant Classification (HAC). Our findings categorize the monthly water samples into three distinct groups based on levels of organic pollution: the first group (July, August, and September) is characterized by high oxygenation levels and significantly low organic pollution, indicating optimal system operation. The second group (April, October, November, and December) exhibits low oxygenation and low organic pollution, promoting sludge settling and pollutant reduction. The third group (January, February, March, May, and June) shows significantly high organic pollution and low oxygenation, which corresponds to unfavorable environmental conditions. Our study demonstrates the effectiveness of multivariate statistical methods in optimizing wastewater treatment processes, providing crucial insights for environmental sustainability and water resource management.
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  • 文章类型: Journal Article
    城市化和经济发展导致全球内城运河和河流的水污染。由于缺乏集中式污水处理厂和公众对环境保护的意识不足,越南CanTho市的BungXang运河面临着水污染问题。使用包括定性和定量信息的结构化问卷收集当地居民的感知。采用回归分析来评估影响受访者对支付意愿(WTP)的决策的影响因素。了解生活污水的环境保护费(10%的增值税-不包括在购买的1立方米自来水的售价中),受访者的年龄和受教育程度对WTP有积极影响,而受访者对水质的看法对WTP产生了负面影响。58.33%的受访者表示WTP改善了运河的水质。他们同意每月支付10,000至15,000越南盾(相当于0.42-0.63美元)的小额费用(1美元=23,700越南盾)。结果表明,环境教育是成功的可持续城市的必由之路。
    Urbanization and economic development cause water pollution in the inner-city canals and rivers globally. Bung Xang canal in Can Tho city of Vietnam is facing problems with water pollution due to the lack of centralized wastewater treatment plants and low public awareness on environmental protection. Perception of local residents was collected using structured questionnaires including both qualitative and quantitative information. Regression analysis was employed to evaluate the factors affecting the decision of respondents on the willingness to pay (WTP) to improve water quality in the Bung Xang canal. Knowledge about the environmental protection fee for domestic wastewater (10% of the VAT-excluded from the selling price of 1 m3 of tap water purchased), age of the respondents and their education levels affected the WTP positively, while respondents\' perception on water quality affected the WTP negatively. There was 58.33% of the respondents showed the WTP for improved water quality in the canal. They agreed to pay a small fee of VND 10,000 to 15,000 (equivalent to USD 0.42-0.63)/month (1 US$= 23,700 VND). The result indicates that environmental education is the only way forward for a successful sustainable urban city.
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  • 文章类型: Journal Article
    与初级保健中抗生素处方的适当性相关的因素研究甚少。特别是,计算机决策支持系统(CDSS)的影响仍然未知。
    我们旨在研究CDSS的摄取及其与医师特征和专业活动的关联。
    自2022年5月以来,已邀请法国初级保健中使用CDSS进行抗生素处方的用户,注册时,完成三个病例小插曲,评估一般实践中经常遇到的临床情况,并被确定为有滥用抗生素的风险。抗生素处方的适当性被定义为符合当前指南的回答率,由个人和具体问题计算。与个体适当抗生素处方相关的医师特征(<50%,50-75%和>75%适当性)通过多变量有序逻辑回归确定。
    2023年6月,6067名医生在CDSS上注册。在回答所有病例小插曲的13851名医生中,抗生素处方的个体适当性水平中位数为77.8%[四分位数范围,66.7%-88.9%],1,353名医生(10%)<50%。在多变量分析中,与适当性相关的医生特征是以前使用过CDSS(OR=1.71,95%CI1.56-1.87),作为一名全科医生与其他专家(OR=1.34,95%CI1.20-1.49),在初级保健工作(OR=1.14,95%CI1.02-1.27),指导学生(OR=1.12,95%CI1.04-1.21)年龄(OR=0.69每10年增加,95%CI0.67-0.71)。
    在CDSS用户中,抗生素处方的个人适用性很高,年轻全科医生的比率更高,以前使用的系统。CDSS可以改善初级保健中的抗生素处方。
    CDSS使用者对抗生素处方的个人适用性很高。CDSS的使用可以被动地改善初级保健中的抗生素处方。与初级保健疾病抗生素处方适当性相关的因素是:以前使用过CDSS,全科专业与其他特色菜,年轻的年龄和学生的指导。
    UNASSIGNED: Factors associated with the appropriateness of antibiotic prescribing in primary care have been poorly explored. In particular, the impact of computerised decision-support systems (CDSS) remains unknown.
    UNASSIGNED: We aim at investigating the uptake of CDSS and its association with physician characteristics and professional activity.
    UNASSIGNED: Since May 2022, users of a CDSS for antibiotic prescribing in primary care in France have been invited, when registering, to complete three case vignettes assessing clinical situations frequently encountered in general practice and identified as at risk of antibiotic misuse. Appropriateness of antibiotic prescribing was defined as the rate of answers in line with the current guidelines, computed by individuals and by specific questions. Physician\'s characteristics associated with individual appropriate antibiotic prescribing (< 50%, 50-75% and > 75% appropriateness) were identified by multivariate ordinal logistic regression.
    UNASSIGNED: In June 2023, 60,067 physicians had registered on the CDSS. Among the 13,851 physicians who answered all case vignettes, the median individual appropriateness level of antibiotic prescribing was 77.8% [Interquartile range, 66.7%-88.9%], and was < 50% for 1,353 physicians (10%). In the multivariate analysis, physicians\' characteristics associated with appropriateness were prior use of the CDSS (OR = 1.71, 95% CI 1.56-1.87), being a general practitioner vs. other specialist (OR = 1.34, 95% CI 1.20-1.49), working in primary care (OR = 1.14, 95% CI 1.02-1.27), mentoring students (OR = 1.12, 95% CI 1.04-1.21) age (OR = 0.69 per 10 years increase, 95% CI 0.67-0.71).
    UNASSIGNED: Individual appropriateness for antibiotic prescribing was high among CDSS users, with a higher rate in young general practitioners, previously using the system. CDSS could improve antibiotic prescribing in primary care.
    Individual appropriateness for antibiotic prescribing is high among CDSS users.CDSS use could passively improve antibiotic prescribing in primary care.Factors associated with appropriateness for antibiotic prescribing for primary care diseases are: prior use of CDSS, general practice speciality vs. other specialities, younger age and mentoring of students.
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  • 文章类型: Journal Article
    确定自然环境中污染物的来源和途径是告知任何缓解过程的关键。土壤的质量磁化率允许一种快速测量磁性矿物浓度的方法,源自采矿或工业过程等人为活动,即,冶炼金属(技术起源),或来自当地基岩(地质成因)。当与土壤的快速地球化学分析相结合时,这尤其有效。多变量分析(MVA)的使用阐明了土壤地球化学与磁化率之间复杂的多组分关系。在土壤开采地点的情况下,被矿山废物污染的土壤的X射线荧光(XRF)光谱数据显示,磁化率与某些贱金属物种之间存在统计学上的显着关系(例如,Fe,Pb,Zn,等。).这里,我们展示了如何使用定性和定量MVA方法来评估土壤污染途径,使用废弃煤和W/Sn矿山(NW葡萄牙)附近土壤的质量磁化率和XRF光谱。主成分分析(PCA)显示了前两个主要成分(PC-1PC-2)如何解释94%的样品变异性,根据它们的地球化学和磁化率将它们分为地质和技术组。回归分析表明,在局部尺度上,土壤地球化学与磁性之间存在很强的正相关(R2>0.95)。这些参数提供了对控制磁化率的多元素变量的洞察力,并表明了通过特定质量的土壤磁性有效评估潜在污染地点的可能性。
    Determining the origin and pathways of contaminants in the natural environment is key to informing any mitigation process. The mass magnetic susceptibility of soils allows a rapid method to measure the concentration of magnetic minerals, derived from anthropogenic activities such as mining or industrial processes, i.e., smelting metals (technogenic origin), or from the local bedrock (of geogenic origin). This is especially effective when combined with rapid geochemical analyses of soils. The use of multivariate analysis (MVA) elucidates complex multiple-component relationships between soil geochemistry and magnetic susceptibility. In the case of soil mining sites, X-ray fluorescence (XRF) spectroscopic data of soils contaminated by mine waste shows statistically significant relationships between magnetic susceptibility and some base metal species (e.g., Fe, Pb, Zn, etc.). Here, we show how qualitative and quantitative MVA methodologies can be used to assess soil contamination pathways using mass magnetic susceptibility and XRF spectra of soils near abandoned coal and W/Sn mines (NW Portugal). Principal component analysis (PCA) showed how the first two primary components (PC-1 + PC-2) explained 94% of the sample variability, grouped them according to their geochemistry and magnetic susceptibility in to geogenic and technogenic groups. Regression analyses showed a strong positive correlation (R2 > 0.95) between soil geochemistry and magnetic properties at the local scale. These parameters provided an insight into the multi-element variables that control magnetic susceptibility and indicated the possibility of efficient assessment of potentially contaminated sites through mass-specific soil magnetism.
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  • 文章类型: Letter
    暂无摘要。
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  • 文章类型: Journal Article
    背景:治疗的总体有利获益-风险状况并不意味着每个患者都将从治疗中获益。我们描述了一种量化个体患者获益-风险权衡的统计方法。
    方法:该方法需要包含主要疗效结果和主要安全性结果的大型RCT:例如,在心肌梗死后的17,779名患者中进行的TIMI-50安慰剂对照试验vorapaxar。多变量回归模型根据每个患者的情况预测缺血性事件(获益)和大出血事件(损害)的风险。因此,对每位患者的预测受益于vorapaxar(缺血事件减少)和预测风险(出血事件增加)进行了估计.根据与全因死亡率的联系,对缺血和出血事件的相对重要性进行了量化,尽管注意到这种权重的局限性。
    结果:总体结果证明了vorapaxar的明显益处和危害。收益和风险的个体间差异很大,有助于区分具有有利利益-风险权衡的患者和没有的患者。这些发现被应用于推荐vorapaxar在多达98.3%的患者中具有有利的死亡率加权获益-风险权衡,在77.2%的缺血性患者中,获益比出血风险大20%,如果每年减少>=0.5%的缺血风险也是必需的,则在低至45.5%的患者中。
    结论:虽然治疗获益与风险的总体RCT是有价值的,确定每个患者的估计绝对收益和风险的模型提供了关于患者特定收益-风险权衡的更有用的见解,更好地实现个性化的治疗决策。
    BACKGROUND: A treatment\'s overall favorable benefit-risk profile does not imply that every individual patient will benefit from the treatment.
    OBJECTIVE: To describe a statistical methodology for quantifying the benefit-risk trade-off in individual patients.
    METHODS: The method requires a large randomized controlled trial containing a primary efficacy outcome and a primary safety outcome, for instance, the Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-Thrombolysis in Myocardial Infarction 50 placebo-controlled trial of vorapaxar in 17 779 patients following myocardial infarction. Multivariate regression models predict each individual patient\'s risk of ischemic events (benefit) and major bleeding events (harm) based on their profile. Hence, each patient\'s predicted benefit from vorapaxar (reduction in ischemic events) and predicted risk (increase in bleeding events) were estimated. The relative importance of ischemic and bleeding events based on links to all-cause mortality was quantified, although the limitations of such weightings are noted.
    RESULTS: Overall results demonstrated both clear benefit and harm from vorapaxar. Substantial interindividual variation in both benefit and risk facilitated distinguishing patients with a favorable benefit-risk trade-off from those who did not. Such findings were applied to recommend vorapaxar in as many as 98.3% of patients in which a favorable mortality-weighted benefit-risk trade-off was present, in 77.2% of patients with ischemic benefit 20% greater than bleeding risk, or in as few as 45.5% of patients if an annual decrease in ischemic risk of ≥0.5% was also required.
    CONCLUSIONS: While overall randomized controlled trials of treatment benefit vs risk are valuable, models determining each individual patient\'s estimated absolute benefit and risk provide more useful insight regarding patient-specific benefit-risk trade-offs to better enable personalized therapeutic decision-making.
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  • 文章类型: Journal Article
    这项研究对微藻进行了毒性测定,微甲壳类动物,和鱼类以及评估鱼类和微甲壳类动物的生化和行为生物标志物,以评估Mirim泻湖的地表水质量,属于世界上最大的水文盆地之一,位于巴西南部。选择了三个不同的采样期(1月,March,和2022年6月)基于水稻种植动态,这是泻湖周围的主要活动。1月,种植园灌溉;三月,水被排入Mirim泻湖,七月是淡季。关于毒性试验,当暴露于3月收集的水中时,微藻的生长受到显著抑制,但是没有观察到杜邦Ceriodaphia的死亡,大型水蚤,还有DanioRerio.关于生物标志物,行为变量对D.magna和D.rerio的综合生物标志物响应(IBR)指数的较高值贡献更大,在三月。冗余分析(RDA)表明生物标志物与非生物参数之间存在相关性,主要是养分(总磷和总氮),耐热大肠杆菌,总固体,和浊度。空间上,在监测过程中没有区别,但在3月份观察到了最显著的生态毒理效应。多变量分析和IBR指数被证明是监测MirimLagoon等水体的有用工具。
    This study performed toxicity assays with microalgae, microcrustaceans, and fish as well as evaluated biochemical and behavioral biomarkers in fish and microcrustaceans to assess the quality of the surface water of Mirim Lagoon, which belongs to one of the largest hydrographic basins in the world, located in southern Brazil. Three distinct sampling periods were chosen (January, March, and June 2022) based on the rice plantation dynamics which is the main activity surrounding the lagoon. In January, the plantation is irrigated; in March, the water is drained into the Mirim Lagoon, and July is the off-season. Concerning toxicity tests, there was significant inhibition in microalgae growth when exposed to water collected in March, but no mortality was observed for Ceriodaphia dubia, Daphnia magna, and Danio rerio. Regarding biomarkers, behavioral variables contributed more to the higher values of the Integrated Biomarker Response (IBR) index for both D. magna and D. rerio, in March. The Redundancy Analysis (RDA) indicated a correlation between the biomarkers for both organisms and abiotic parameters, mainly nutrients (total phosphorus and total nitrogen), thermotolerant coliforms, total solids, and turbidity. Spatially, there was no difference during monitoring, but the most significant ecotoxicological effects were observed in March. Multivariate analysis and the IBR index proved to be useful tools for monitoring of water bodies such as Mirim Lagoon.
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  • 文章类型: English Abstract
    在日本,使用称为“追踪报告(TR)”的报告从药房向医疗机构提供信息并不普遍,特别是在癌症化疗领域。确定与提交TRs有关的因素可以增强TRs的必要性。这项研究的目的是通过问卷调查阐明与癌症化疗有关的TRs提交相关的因素。在2023年1月为药剂师举行的关于癌症化疗的实时网络研讨会上进行了问卷调查。经过问卷调查,参与者被分为在研讨会前1个月内提交了至少一项关于癌症化疗的TR的参与者(TR组)和未提交的参与者(非TR组).进行多变量分析以确定与提交关于癌症化疗的TRs相关的因素。在118名参与者中,我们分析了93名参与配药的药学药剂师的回答,这些药剂师同意参与本研究并符合所有问卷的要求.TR组包括21名参与者,非TR组包括72名参与者。作为多变量分析的结果,“对接受癌症化疗的患者进行咨询和随访的经验(比值比:4.81,p=0.02)”和“工作场所类型(比值比:3.79,p=0.02)”显着增加了提交关于癌症化疗的TR的发生率。据透露,干预癌症化疗病例的经验以及每天可以处理癌症化疗处方的环境对于提交有关癌症化疗的TR很重要。
    In Japan, use of a report for providing information from pharmacies to medical institutions called as \"tracing report (TR)\" is not widespread especially in the field of cancer chemotherapy. Identification of the factors related to submission of TRs could enhance the necessity of TRs. The purpose of this study is to clarify the factors related to submission of TRs regarding cancer chemotherapy through a questionnaire survey. A questionnaire survey was conducted at the live web-based seminar regarding cancer chemotherapy held for pharmacists in January 2023. After the questionnaire survey, the participants were divided into those who had submitted at least one TR regarding cancer chemotherapy within one month before the seminar (TR group) and those who had not (non-TR group). The multivariate analysis was conducted to identify factors related to submission of TRs regarding cancer chemotherapy. Of 118 participants, the responses from 93 pharmacy pharmacists involved in dispensing drugs who agreed to participate in this study and fulfilled all questionnaire were analyzed. TR group included 21 participants and non-TR group included 72. As a result of multivariate analysis, \"Years of experience in counseling and following-up with patients undergoing cancer chemotherapy (odds ratio: 4.81, p=0.02)\" and \"Types of workplaces (odds ratio: 3.79, p=0.02)\" significantly increased the incidence of submission of TRs regarding cancer chemotherapy. It was revealed that experience of intervention in cancer chemotherapy cases and an environment in which prescriptions for cancer chemotherapy can be handled on a daily basis are important for submission of TRs regarding cancer chemotherapy.
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  • 文章类型: Journal Article
    诺奎湖,Ouémédelta水文系统的主要组成部分,是贝宁最大的泻湖-河口生态系统。最近的研究表明,底栖过程将积极参与该生态系统富营养化和生物地球化学循环的维持。为了了解底部对湖泊水质的影响,从2020年7月至2021年12月,在分布在整个湖泊上的19个(19个)站点的网络上,对底部水域的水质进行了每月十(10)个参数的跟踪。使用单变量和多变量分析技术来评估这些水域的时空动态。Kruskal-Wallis测试,PCA,相关分析和判别分析均显示,与湖泊周围人为活动的影响以及气候条件对内部过程的影响相比,水文状况对养分浓度的影响非常显着。的确,来自Ouémé流域的水流入是湖中磷的主要贡献者,而底栖过程是氮的最重要贡献者。聚类分析定义了诺奎湖中三个显著不同的区域:河道,湖和河口的中心。每个集群中的单个站点可用于对整个湖泊的水质进行空间评估。
    Lake Nokoué, a major component of the hydrographic system of the Ouémé delta, is the largest lagoon-estuarine ecosystem in Benin. Recent studies have shown that benthic processes would actively participate in the maintenance of the eutrophication and biogeochemical cycle of this ecosystem. In order to understand the implication of the bottom on the quality of the waters of the lake, a monthly follow-up of ten (10) parameters of quality of the waters of the bottom was undertaken from July 2020 to December 2021 on a network of nineteen (19) stations distributed on the whole lake. Univariate and multivariate analysis techniques were used to assess the spatial and temporal dynamics of these waters. The Kruskal-Wallis test, PCA, correlation analysis and discriminant analysis all showed a very marked influence of the hydrological regime on the concentration of nutrients compared to the influence of anthropogenic activities around the lake and an influence of climatic conditions on internal processes. Indeed, water inflows from the Ouémé watershed are the main contributors of phosphorus in the lake while benthic processes are the most important contributors of nitrogen. Cluster analysis defined three significantly different areas in Lake Nokoué: the channel, the centre of the lake and the river mouth. A single station in each cluster could be used for a spatial assessment of water quality over the entire lake.
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  • 文章类型: Journal Article
    为了充分评估地表水环境条件,必须考虑许多物理化学和生物监测参数。然而,在某些情况下,对不良水质状况进行简单快速的评估至关重要。这项工作提出了一种通用方法,用于同时监测许多参数并以实时模式早期检测失控样本。该方法使用基于主成分分析(PCA)模型的多变量统计质量控制图,其中包含两个众所周知的过程或系统中异常行为的度量:Hoteling的T2统计量和Q统计量。拟议的TQ_PCA质量指标提供了水样质量的在线评估,没有关于所需监控参数的控制限制的具体知识和假设。使用为训练/参考样品建立的PCA模型通过简单控制图评估水样品。已使用奥得河的水质数据对拟议指数的威力进行了检验,包括最近欧洲河流历史上最大的生态灾难。拟议的指数对波兰站的物理化学水质数据集以及德国/法兰克福站的物理化学和生物水质数据集显示出出色的分析性能,确认先前的报道。统计指数连续报告报警次数,灾难发生前一个月,个别参数没有明显变化。本研究中提出的方法证明了评估主要水质参数的能力,其变化先于不常见的事件。所提出的TQ_PCA指数可以很容易地扩展到涉及来自任何工业化学过程的监测参数的大数据集的任何研究。
    Many physicochemical and biological monitored parameters must be taken into consideration to fully evaluate the surface water environmental condition. However, there are situations where a simple and rapid assessment of the poor water quality situations is critically important. This work presents a universal methodology for monitoring of many parameters simultaneously and early detection out-of-control samples in a real-time mode. The approach uses multivariate statistical quality control chart based on Principal Component Analysis (PCA) model with two well-known measures of abnormal behaviour in a process or system: Hoteling\'s T2 statistics and Q-statistic. The proposed TQ_PCA quality index provides on-line assessment of the water sample quality, with no specific knowledge and assumptions about control limits for monitored parameters required. A water sample is assessed through the simple control chart using the PCA model established for training/reference samples. The power of the proposed index has been tested using water quality data from the Oder River, including the time of the largest ecological disaster in recent European river history. The proposed index showed excellent analysis performance for physicochemical water quality dataset from Polish stations and physicochemical and biological water quality dataset from German/Frankfurt station, confirming earlier reports. There were consecutive number of alarms reported by the statistical index, a month prior to the disaster when there were no evident changes in the individual parameters. The method presented in this study demonstrated capability of assessment of the major water quality parameters, whose changes preempt the uncommon event. The presented TQ_PCA index could be easily extended to any research involving a large dataset of monitoring parameters from any industrial chemical process.
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