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  • 文章类型: Journal Article
    近年来,微塑料(MPs)广泛存在于环境中,对生态系统构成潜在风险,这引起了人们的注意。使用生物指标一直是了解污染水平的好方法,生物利用度,污染物的生态风险。然而,只有少数研究调查了红树林生态系统中的国会议员,几乎没有国会议员的生物指标。在这里,研究了红树林沉积物中MP的分布和红树林中的招音蟹(Tubucaarcuata)。结果表明,MPs的丰度值分别为1,160~12,120个项目/kg和11~100个项目/ind。在红树林沉积物和提琴蟹中,分别。在红树林沉积物和招潮蟹中检测到的MP的主要形状是大小为20-1,000μm的碎片,大量发现了50-1,000μm的较大MPs。聚丙烯(PP),这是一种最常用的塑料材料,是主要的聚合物类型。MP在招潮蟹中的分布与地表红树林沉积物中的分布非常相似,其丰度之间具有很强的线性相关(R2>0.8和p<0.05)。因此,红树林沉积物中的MP污染水平可以通过研究招潮蟹中的MP污染来确定。此外,目标群体指数(TGI)的结果表明,招潮蟹更喜欢在红树林沉积物中喂食特定的MP。我们的发现表明,招潮蟹适合作为评估红树林沉积物中MP污染的生物指标。
    In recent years, microplastics (MPs) have been widely found in the environment and pose potential risks to ecosystems, which attracted people\'s attention. Using bioindicators has been a great approach to understanding the pollution levels, bioavailability, and ecological risks of pollutants. However, only few studies have investigated MPs in mangrove ecosystems, with few bioindicators of MPs. Herein, the distribution of MPs in mangrove sediments and fiddler crabs (Tubuca arcuata) in mangroves was investigated. Results showed that the abundance values of MPs are 1,160‒12,120 items/kg and 11‒100 items/ind. in mangrove sediments and fiddler crabs, respectively. The dominant shape of MPs detected in mangrove sediments and fiddler crabs was fragments with sizes of 20‒1,000 μm, larger MPs of 50-1,000 μm were found in abundance. Polypropylene (PP), which is one of the most commonly used plastic materials, was the main polymer type. The distribution of MPs in fiddler crabs closely resembled that in surface mangrove sediments with a strong linear correlation (R2 > 0.8 and p < 0.05) between their abundance. Therefore, the MP contamination level in mangrove sediments can be determined by studying MP pollution in fiddler crabs. Moreover, the results of the target group index (TGI) indicated that fiddler crabs prefer feeding specific MPs in mangrove sediments. Our findings demonstrate the suitability of fiddler crabs as bioindicators for assessing MP pollution in mangrove sediments.
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  • 文章类型: Journal Article
    目的:本研究探讨了血清25-羟维生素D3(25(OH)D3)水平与颈动脉内中膜厚度(CIMT)的关系,以及有吸烟史的个体存在颈动脉粥样硬化斑块。
    方法:共469例怀疑有颈动脉粥样硬化的患者,年龄52至73岁,平均年龄65.26±4.37岁,于2023年1月至2023年10月从提交人的医院招募。所有患者均有近5年的吸烟史。根据他们的血清25(OH)D3水平,他们分为两组:正常组(血清水平30-50ng/mL,n=300)和缺乏组(<30ng/mL,n=169)。收集两组患者的一般细节。采用颈动脉超声评估脉搏波传导速度(PWV),颈动脉顺应性系数(CC),和CIMT。血液化学分析测定血清脂质代谢指标包括总胆固醇(TC),低密度脂蛋白胆固醇(LDL-C),和高密度脂蛋白胆固醇(HD-LC)。通过皮尔逊相关分析CIMT与各变量之间的关系,采用logistic回归分析确定影响颈动脉斑块发展的危险因素.
    结果:两组患者一般资料差异无统计学意义(P>0.05)。与25(OH)D3正常组相比,25(OH)D3缺乏组患者的左右PWV和CC升高(P<0.05)。与正常组相比,缺乏组的MT和斑块面积更大(P<0.05)。此外,缺乏组表现出更高的TC水平,LDL-C,HD-LC与正常组比拟(P<0.05)。发现TC之间呈中度正相关,LDL-C,和CIMT(P<0.05),25(OH)D3与CIMT之间存在很强的正相关(P<0.05)。在吸烟者中,颈动脉斑块的形成与患者年龄等因素有关,CIMT,血清LDL-C,和25(OH)D3水平(P<0.05)。随着年龄的增长,CIMT,LDL-C水平升高,25(OH)D3水平下降,吸烟者颈动脉斑块风险增加(P<0.05)。
    结论:25(OH)D3水平较低的吸烟者表现出较高的MTCI和更突出的颈动脉粥样硬化斑块,表明动脉僵硬度增加和心血管风险升高。这些发现证明了至关重要的意义,即维生素D水平不足可能导致吸烟者患动脉粥样硬化的风险更高。
    OBJECTIVE: This study explores the association of serum 25-hydroxyvitamin D3 (25(OH)D3) levels with carotid artery intima-media thickness (CIMT), and the presence of carotid atherosclerotic plaques in individuals with a history of smoking.
    METHODS: A total of 469 patients suspected of having carotid atherosclerosis, aged 52 to 73 years with an average age of 65.26 ± 4.37 years, were recruited from the author\'s hospital from January 2023 to October 2023. All patients had a smoking history of nearly 5 years. Based on their serum 25(OH)D3 levels, they were divided into two groups: the normal group (serum level 30-50 ng/mL, n = 300) and the deficiency group (<30 ng/mL, n = 169). General details of the two patient groups were collected. Carotid artery ultrasound was employed to assess pulse wave velocity (PWV), carotid artery compliance coefficient (CC), and CIMT. Blood chemistry analysis measured serum lipid metabolism indicators including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HD-LC). The relationship between CIMT and each variable was analyzed through Pearson correlation, and logistic regression was used to identify risk factors influencing carotid artery plaque development.
    RESULTS: General patient information between the two groups showed no significant differences (P > 0.05). Patients in the 25(OH)D3 deficiency group exhibited elevated left and right PWV and CC compared to the 25(OH)D3 normal group (P < 0.05). The deficiency group exhibited larger CIMT and plaque area compared to the normal group (P < 0.05). Additionally, the deficiency group demonstrated higher levels of TC, LDL-C, and HD-LC compared to the normal group (P < 0.05). A moderate positive correlation was found between TC, LDL-C, and CIMT (P < 0.05), while a strong positive correlation existed between 25(OH)D3 and CIMT (P < 0.05). In smokers, the formation of carotid artery plaque was associated with factors such as patient age, CIMT, serum LDL-C, and 25(OH)D3 levels (P < 0.05). As age, CIMT, LDL-C levels increased, and 25(OH)D3 levels decreased, the risk of carotid plaques in smokers increased (P < 0.05).
    CONCLUSIONS: Smokers with lower 25(OH)D3 levels exhibit higher CIMT and more prominent carotid atherosclerotic plaques, indicating increased arterial stiffness and elevated cardiovascular risk. These findings demonstrate crucial implications that insufficient levels of vitamin D may potentially contribute to a higher risk of atherosclerosis among smokers.
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  • 文章类型: Journal Article
    本研究旨在利用五种热加工方法的效果,即蒸汽(SM),沸腾(BO),油炸(FY),焙烧(RO),和真空密封(SV),在感官上,物理化学性质,以及冷藏过程中草鱼肉的微生物组成,与未加热的生肉(RW)一起作为对照。结果表明,热处理提高了冷藏草鱼肉的感官品质和货架期,其保质期为RW This study aimed to employed the effects of five thermal processing methods, namely steaming (SM), boiling (BO), frying (FY), roasting (RO), and vacuum sealing (SV), on the sensory, physicochemical properties, and microbial composition of grass carp meat during refrigerated storage, alongside unheated raw meat (RW) as control. The results showed that thermal treatment improved the sensory quality and shelf life of refrigerated grass carp meat, and their shelf life was RW < BO
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  • 文章类型: Journal Article
    酸枣是医药和食品的重要水果,影响各种生物活性。虽然中国酸枣种子(酸枣仁)富含油脂,它的脂质分布受提取过程的显著影响。然而,迄今为止,尚无研究全面分析使用不同方法加工的酸枣仁精液油的脂质组成和生物活性。在这项研究中,我们比较了常用压榨的效果,超声波辅助,和索氏提取方法对脂质成分,特点,酸枣仁油的抗氧化性能。鉴定了19个亚类和390个脂质分子种类,其中24种脂质分子可能被用作不同加工方法的生物标志物。相关分析显示,57个脂质与抗氧化能力显著相关(r>0.9,P<0.05)。这些结果表明,酸枣仁精液油富含生物活性脂质。这些数据极大地扩展了我们对酸枣仁精液油的生物活性脂质的理解。此外,它可以为酸枣仁在功能性产品或食品工业中的应用提供有用的信息,以及对活性植物油加工效果的新见解。
    Chinese sour jujube is an important fruit for both medicine and food and effects various biological activities. Although the Chinese sour jujube seed (Ziziphi spinosae semen) is rich in oil, its lipid profiles is significantly affected by the extraction process. However, no studies to date have comprehensively analysed the lipid composition and bioactivity of Ziziphi spinosae semen oil processed using different methods. In this study, we compared the effects of commonly-used pressed, ultrasonic-assisted, and Soxhlet extraction methods on the lipid composition, characteristics, and antioxidant properties of Ziziphi spinosae semen oil. Nineteen subclasses and 390 lipid molecular species were identified, of which 24 lipid molecular species could potentially be used as biomarkers for different processing methods. Correlation analysis revealed that 57 lipids were significantly correlated with the antioxidant capacity (r > 0.9 and P < 0.05). These results indicate that Ziziphi spinosae semen oil is rich in bioactive lipids. These data greatly expand our understanding of the bioactive lipids of Ziziphi spinosae semen oil. Additionally, it could provide useful information for Ziziphi spinosae semen oil applications in functional products or the food industry and new insights into the effects of active vegetable oil processing.
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  • 文章类型: Journal Article
    KOJI意识(KA)筛选测试评估人类的运动功能。我们旨在分析年龄与KA筛查评分之间的相关性,并确定发生显着下降的特定年龄。共有793名健康参与者(234名女性)接受了年龄和性别的基本信息采访,并完成了KA筛查测试。除了计算KA考试的总分外,计算颈肩胛骨上肢复合体(NSU)的评分,树干,和下肢(LE)段。使用Spearman的等级相关系数来评估测试的有效性。此外,采用贝叶斯线性回归估计KA分数的变化点,有助于识别与运动功能显着下降相关的临界年龄。KA筛查总体和单独的身体部分得分与性别的年龄呈负相关(对于女性和男性,KA总分,ρ=-0.443,ρ=-0.344;NSU段,ρ=-0.431,ρ=-0.427;树干段,ρ=-0.210,ρ=-0.473;LE段:ρ=-0.43,ρ=-0.507)。此外,使用线性回归分析的变点分析显示,KA筛查总分在49.1岁时急剧下降(95%可信区间:37.503,68.366).结果表明,随着年龄的增长,KA总分下降-0.196(95%可信区间:-0.335,-0.049),在49.1岁以上的人群中,KA总分每增加1岁,还会降低0.255(95%可信区间:-0.485,-0.054).在NSU部分,从50岁开始,女性的下降速度比男性快。KA筛查测试总分在49.1岁时急剧下降。这些结果可能有助于设定治疗目标,锻炼,与年龄相关的运动功能下降的生活方式计划。
    The KOJI AWARENESS (KA) screening test assesses motor function in humans. We aimed to analyze the correlation between age and KA screening scores and to identify the specific age at which a significant decline occurs. A total of 793 healthy participants (234 females) were interviewed for basic information on age and sex and completed the KA screening test. In addition to calculating the total score from the KA test, the scores were calculated for the neck-scapula-upper extremity-complex (NSU), trunk, and lower extremity (LE) segments. Spearman\'s rank correlation coefficient was used to assess the validity of the test. Additionally, Bayesian linear regression was employed to estimate the change point in KA scores, facilitating the identification of a critical age associated with a notable decline in motor function. KA screening total and separate body segment scores were negatively correlated with age in both gender (for female and male, KA total score, ρ = - 0.443, ρ = - 0.344; NSU segment, ρ = - 0.431, ρ = - 0.427; trunk segment, ρ = - 0.210, ρ = - 0.473; LE segment: ρ = - 0.43, ρ = - 0.507). Furthermore, a change-point analysis using linear regression analysis showed that KA screening total scores declined sharply at the age of 49.1(95% credible interval: 37.503, 68.366). The result show that total KA scores decrease - 0.196 (95% credible interval: - 0.335,  - 0.049) for every 1 year of age increase, and for ages over 49.1, total KA scores additionally decrease - 0.255 (95% credible interval: - 0.485, - 0.054) for every 1 year of age increase. In the NSU segment, females showed a more rapid decline than males from the age of 50 years. KA screening test total scores declined sharply at the age of 49.1. These results may be useful in setting treatment goals, exercise, and lifestyle programs for age-related decline in motor function.
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  • 文章类型: Journal Article
    背景:适当的身体活动(PA)和良好的睡眠对母体和胎儿健康有益。本文旨在探讨妊娠早期和中期健康女性的PA和睡眠质量与心理健康和妊娠结局的关系。
    方法:对268例健康孕妇作为研究对象进行回顾性分析。134分别在妊娠早期(FT)和妊娠中期(ST)。他们的基线临床数据分别在怀孕的两个阶段获得。采用妊娠期体力活动问卷-中文版(PPAQ-C)/匹兹堡睡眠质量指数(PSQI)量表对受试者的PA/睡眠质量进行评定。通过医院焦虑和抑郁量表(HADS)评估心理健康。采用Spearman相关分析法分析PA、睡眠质量与心理健康的相关性。所有受试者的妊娠结局,中等强度(MI)PA和睡眠质量与不良妊娠结局的关联,并分析不良结局的独立影响因素。
    结果:ST组的孕妇表现出更高水平的MI,睡眠质量差,焦虑和抑郁水平低于FT组。焦虑和抑郁与MI呈负相关,但与妊娠早期和中期的PSQI评分呈正相关。MI≥7.5MET-h/周和良好的睡眠质量与不良妊娠结局发生率降低相关。
    结论:妊娠早期和中期的MI≥7.5MET-h/周和良好的睡眠质量有利于心理健康,并显着减少不良妊娠结局的发生。
    BACKGROUND: Appropriate physical activity (PA) and good sleep are beneficial to maternal and fetal health. This paper sought to explore the associations of PA and sleep quality among healthy women at the first and second trimesters of pregnancy on mental health and pregnancy outcomes.
    METHODS: Totally 268 healthy pregnant women were retrospectively analyzed as study subjects, 134 each in the first trimester (FT) and second trimester (ST). Their baseline clinical data were obtained respectively at two stages of pregnancy. The PA/sleep quality of subjects were assessed through the Pregnancy Physical Activity Questionnaire-Chinese version (PPAQ-C)/Pittsburgh Sleep Quality Index (PSQI) scale. The mental health was assessed via the Hospital Anxiety and Depression Scale (HADS). The correlations of PA and sleep quality with mental health were analyzed using Spearman correlation analysis. Pregnancy outcomes of all subjects, associations of moderate intensity (MI) PA and sleep quality with adverse pregnancy outcomes, and independent influencing factors for adverse outcomes were analyzed.
    RESULTS: Pregnant women in the ST group exhibited higher levels of MI, worse sleep quality, and lower levels of anxiety and depression than those in the FT group. Anxiety and depression were negatively correlated with MI but positively linked with PSQI scores at the first and second trimesters. MI ≥ 7.5 MET-h/week and good sleep quality were associated with a reduced incidence of adverse pregnancy outcomes.
    CONCLUSIONS: MI ≥ 7.5 MET-h/week and good sleep quality at the first and second trimesters of pregnancy benefit mental health and markedly reduce the occurrence of adverse pregnancy outcomes.
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  • 文章类型: Journal Article
    土鸡对家庭的收入和蛋白质非常重要。然而,他们的表现通常很差,特别是在小农经营下,尽管他们有可能表现得更好。这些鸡的性能可以通过选择性育种来改善。然而,为了成功,有必要充分了解这些鸡的表型和生产特征。因此,这项研究旨在表征这些鸡的表型及其在小规模农民中的生产系统。
    对177名小农进行了结构化问卷调查。在Luapula中,总共对平均体重为1.66kg的538只鸡进行了表型分析,Muchinga,和赞比亚北部省份。
    土鸡的所有权以雌性为主(65.37%),大多数(64.31%)获得了初等教育。大多数人将鸡饲养在家庭房屋中(42.03%)。所有的农民都让他们的鸡去捡饲料,其中45.58%提供基本补充。大多数(84.10%)农民从社区内购买了他们的品种,平均羊群大小为12.5只鸡/户,他们大多(78.09%)是自由放养的。大多数(77.39%)实行扑杀,生产率低是剔除的最常见原因(84.45%)。只有59.01%的农民实行选择性育种,86.22%的人进行了不受控制的交配。公鸡和母鸡首次交配的年龄分别为6.8个月和6.34个月,分别,6.73个月是第一个鸡蛋的年龄。需要15.43天才能达到13个鸡蛋的平均离合器大小。8周时孵化率和死亡率分别为83.44%和67.57%,分别。所有的鸡都被当作活鸡出售,大多数(51.59%)的农民在7.23个月时在社区内出售了鸡只。疾病和捕食者是影响研究区域农民的最常见挑战。与兽医协商,疫苗接种,驱虫并不常见,而主要使用民族兽药治疗病鸡很常见。最常见的定性性状为棕色(27.88%)和混色(26.77%),白皮肤(91.45%)和小腿(48.70%),单梳型(91.08%),红耳垂(55.76%),橙色眼睛(78.07%)。所有线性身体测量值与平均1.66kg体重呈正相关且显着相关,选择它们中的任何一个都会导致体重相应增加的指标。主成分分析提取了两个成分,占总变异的69.38%。
    这些鸡的表型及其生产系统的多样性表明,通过实施育种计划进行改进的巨大潜力。
    UNASSIGNED: Indigenous chickens are very important to households for income and protein. However, their performance is usually poor, especially under small-scale farmer management, despite their potential to perform better. The performance of these chickens can be improved by selective breeding. However, for this to be a success, there is a need to understand the phenotypic and production characteristics of these chickens fully. Hence, this study aimed to characterize the phenotypes of these chickens and their production system among small-scale farmers.
    UNASSIGNED: A structured questionnaire was administered to 177 small-scale farmers. A total of 538 chickens whose mean weight was 1.66 kg were individually phenotyped in Luapula, Muchinga, and Northern provinces of Zambia.
    UNASSIGNED: Ownership of the indigenous chickens was dominated by females (65.37%), with most (64.31%) having attained primary education. Most housed their chickens in family houses (42.03%). All the farmers let their chickens scavenge for their feed, with 45.58% of them providing basic supplementation. Most (84.10%) farmers bought their breed stock from within their community and had a mean flock size of 12.5 chickens/household, which they mostly (78.09%) kept as free-range. The majority (77.39%) practiced culling, with low productivity being the most common reason for culling (84.45%). Only 59.01% of farmers practiced selective breeding, while 86.22% practiced uncontrolled mating. The age at first mating for cocks and hens was 6.8 months and 6.34 months, respectively, with 6.73 months being the age at first egg. It takes 15.43 days to reach a mean clutch size of 13 eggs. The hatchability and mortality at 8 weeks were 83.44% and 67.57%, respectively. All chickens were sold as live chickens, and the majority (51.59%) of the farmers sold their chickens within the community at 7.23 months. Diseases and predators were the most common challenges affecting farmers in the study area. Consultations with veterinarians, vaccinations, and deworming were uncommon while treating sick chickens mostly using ethnoveterinary medicines was common. The most common qualitative traits were brown (27.88%) and mixed (26.77%) plumage color, white skins (91.45%) and shanks (48.70%), single comb type (91.08%), red earlobe (55.76%), and orange eyes (78.07%). All linear body measurements positively and significantly correlated with the body weight averaging 1.66kgs, an indicator that selection for any of them would result in a corresponding increase in body weight. Principal Component Analysis extracted two components with 69.38% of the total variation.
    UNASSIGNED: The diversity in phenotypes of these chickens and their production systems indicate huge potential for improvement by implementing breeding programs.
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  • 文章类型: Journal Article
    本研究旨在研究自然风干发酵(NF)云南香肠中真菌群落和风味物质的变化。变温干燥(VT),和恒温干燥(CT),并分析真菌群落与风味物质之间的潜在关系。结果表明,NF组和VT组更有利于增强云南香肠中优势真菌和特征风味物质的积累。Glu,阿拉,他的,和Lys根据其味觉活性值(TAV≥1)被鉴定为关键味觉物质。在香肠样品中总共检测到272种挥发性化合物(VOCS),同时根据气味活性值(OAV≥1)筛选了28种关键香气化合物。多变量统计分析表明,12个关键香气化合物(VIP>1)可被认为是区分性化合物,包括(E,E)-2,4-壬烯,非肛门,庚醛,苯甲醛,Dodecanal,环己醇,和己基苯,等。此外,Wickerhamomyces和Debaryomyces与大多数关键风味物质和理化指标呈正相关(|r|>0.6,P<0.05)。是云南香肠中潜在的风味真菌。
    This study aimed to investigate alterations in the fungal community and flavor substances in Yunnan-style sausages subjected to natural air-dried fermentation (NF), variable-temperature drying (VT), and constant-temperature drying (CT) and analyze the potential relationship between fungal community and flavor substances. The findings revealed that the NF group and VT group were more conducive to enhancing the accumulation of dominant fungi and characteristic flavor substances in Yunnan-style sausages. Glu, Ala, His, and Lys were identified as key taste substances based on their taste activity values (TAV ≥ 1). A total of 272 volatile compounds(VOCS) were detected in the sausage samples, while 28 key aroma compounds were screened based on the odor activity value (OAV ≥ 1). Multivariate statistical analysis showed that 12 key aroma compounds (VIP > 1) could be considered discriminative compounds, including (E,E)-2,4-nonadienal, nonanal, heptanal, benzaldehyde, Dodecanal, cyclohexanol, and hexyl-Benzene, etc. Furthermore, Wickerhamoomyces and Debaryomyces were positively correlated with most of the key flavor substances and physicochemical indices (|r| > 0.6, P < 0.05), which were potential flavor-contributing fungi in Yunnan-style sausages.
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  • 文章类型: Journal Article
    在中国,人口增长和老龄化部分抵消了空气污染控制措施对公众健康的好处,强调了对精确PM2.5监测和绘图的持续需求。尽管流行,用于估算PM2.5浓度的卫星衍生的气溶胶光学深度(AOD)方法通常会遇到明显的空间数据空白。此外,目前的研究仍需要更好地表征PM2.5的时空异质性。应对这些挑战,我们开发了一个采用极限梯度提升(XGBoost)算法的两阶段模型。通过纳入改进的时空因素,我们在不使用AOD产品的情况下,实现了2020年中国每天1公里PM2.5的高精度全覆盖映射。具体来说,模型1开发了改进的时间编码和地形分类因子(DC),而模型2通过整合观测值和估计值来构造增强的空间自相关项(Ps)。值得注意的是,模型2在基于10倍样本的交叉验证中表现出色,达到0.948的确定系数,平均绝对误差为3.792微克/立方米,均方根误差为7.144微克/立方米,平均相对误差为14.171%。特征重要性和Shapley加法扩张(SHAP)分析确定了预测因子在模型训练和结果预测中的相对重要性,虽然相关分析确定了改进的时间编码之间的强联系,PM2.5浓度,和重要的气象因素。双向部分依赖图(PDP)进一步探讨了这些因素之间的相互作用及其对PM2.5水平的影响。与传统方法相比,改进的时间编码与季节变化更紧密地吻合,并与气象因素更有效地协同作用。此外,DC的结构化特性有助于模型训练,虽然改进的Ps更有效地捕获了PM2.5的空间自相关,表现优于传统PS。总的来说,这项研究有效地代表了时空信息,从而提高模型精度并实现无缝的大规模PM2.5估计。它提供了对变量和模型的深刻见解,为未来的空气污染研究提供了重要的启示。
    In China, population growth and aging have partially negated the public health benefits of air pollution control measures, underscoring the ongoing need for precise PM2.5 monitoring and mapping. Despite its prevalence, the satellite-derived Aerosol Optical Depth (AOD) method for estimating PM2.5 concentrations often encounters significant spatial data gaps. Additionally, current research still needs better representation of PM2.5 spatiotemporal heterogeneity. Addressing these challenges, we developed a two-stage model employing the Extreme Gradient Boosting (XGBoost) algorithm. By incorporating improved spatiotemporal factors, we achieved high-precision and full-coverage daily 1-km PM2.5 mappings across China for the year 2020 without utilizing AOD products. Specifically, Model 1 develops improved temporal encodings and a terrain classification factor (DC), while Model 2 constructs an enhanced spatial autocorrelation term (Ps) by integrating observed and estimated values. Notably, Model 2 excelled in 10-fold sample-based cross-validation, achieving a coefficient of determination of 0.948, a mean absolute error of 3.792 μg/m³, a root mean square error of 7.144 μg/m³, and a mean relative error of 14.171%. Feature importance and Shapley Additive exPlanations (SHAP) analyses determined the relative importance of predictors in model training and outcome prediction, while correlation analysis identified strong links between improved temporal encodings, PM2.5 concentrations, and significant meteorological factors. Two-way Partial Dependence Plots (PDPs) further explored the interactions among these factors and their impact on PM2.5 levels. Compared to traditional methods, improved temporal encodings align more closely with seasonal variations and synergize more effectively with meteorological factors. Besides, the structured nature of DC aids in model training, while the improved Ps more effectively captures PM2.5\'s spatial autocorrelation, outperforming traditional Ps. Overall, this study effectively represents spatiotemporal information, thereby boosting model accuracy and enabling seamless large-scale PM2.5 estimations. It provides deep insights into variables and models, providing significant implications for future air pollution research.
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  • 文章类型: Journal Article
    本研究考察了气候变化对河南省冬小麦生产的影响。分析,在利用GLASSLAI数据的情况下,重点关注冬小麦种植面积的变化。此外,还对冬小麦生育期气象因子的时空趋势进行了综合评估。研究结果表明,整个河南省的累积温度呈波动上升趋势,范围从3145°C到3424°C,从北向南逐渐上升。特别是,1980年至2019年的降水模式显示出有限的显著趋势,而在1983年、2004年、2009年和2016年观察到了显著的突变。地理上,河南省西南部的降水量大于东北部。此外,观察到日照时数呈波动下降趋势,从北向南逐渐减少。研究进一步突出了洛阳西北地区和驻马店东北部冬小麦种植频次的增加,相比之下,郑州和开封的下降。累积温度与冬小麦种植面积的扩大呈正相关(R2=0.685),而日照时数发挥抑制作用(R2=0.637)。在气象因素中,积温是最关键的决定因素,其次是降水,日照时间的影响相对较小。产量与累积温度呈正相关(R2=0.765),与日照时数呈负相关(R2=-0.614)。这一发现与气象因素对冬小麦产量的影响一致。这项研究的结果增强了对气候变化的潜在机制如何影响作物产量的理解。
    This study examines the impact of climate change on winter wheat production in Henan Province. The analysis, under the utilization of GLASS LAI data, focuses on shifts in the planting areas of winter wheat. In addition, a comprehensive assessment of the spatiotemporal trends in meteorological factors during the winter wheat growth period has also been conducted. The findings reveal a fluctuating increase in accumulated temperature across Henan Province, ranging from 3145 °C to 3424 °C and exhibiting a gradual rise from north to south. In particular, precipitation patterns from 1980 to 2019 showed limited significant trends, while notable abrupt changes were observed in 1983, 2004, 2009, and 2016. Geographically, southwestern Henan Province experiences greater precipitation than the northeast. Moreover, a fluctuating downward trend in sunshine hours has been observed, gradually decreasing from north to south. The study further highlights an increase in winter wheat planting frequency in the northwestern region of Luoyang and the northeastern part of Zhumadian, contrasted by a decrease in Zhengzhou and Kaifeng. Accumulated temperature is positively correlated with the expansion of winter wheat planting areas (R2 = 0.685), while sunshine hours exert a suppressive effect (R2 = 0.637). Among meteorological factors, accumulated temperature emerges as the most crucial determinant, followed by precipitation, with sunshine hours having a relatively minor influence. Yield demonstrates a positive association with accumulated temperature (R2 = 0.765) and a negative correlation with sunshine hours (R2 = -0.614). This finding is consistent with the impact of meteorological factors on winter wheat production. The results of this study enhance the understanding of how the underlying mechanisms of climate change impact crop yields.
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