univariate analysis

单变量分析
  • 文章类型: Multicenter Study
    背景:双相情感障碍(BD)患者普遍存在精神病症状。然而,在西方人群中进行了几乎所有关于有(BDP)和无(BDP-)精神病症状的患者之间的社会人口统计学和临床因素差异的研究,在中国已知的信息有限。
    方法:招募来自中国7个中心的555例BD患者。采用标准化程序收集患者的社会人口统计学和临床特征。根据终生精神病症状的存在,将患者分为BDP或BDP-组。采用Mann-WhitneyU检验或卡方检验分析BD+和BD-患者在社会人口统计学和临床因素方面的差异。采用多因素logistic回归分析探讨与BD患者精神病性症状独立相关的因素。根据患者的诊断类型分为BDI组和BDII组后,再次进行上述分析。
    结果:共有35名患者拒绝参加,其余520例患者纳入分析.与BD-患者相比,患有BDP+的患者在第一次情绪发作时更有可能被诊断为BDI和躁狂/轻躁狂/混合极性。此外,他们更容易被误诊为精神分裂症,而不是重度抑郁症,住院的频率更高,使用抗抑郁药的频率较低,并使用了更多的抗精神病药和情绪稳定剂。多变量分析显示BDI的诊断,更常见的误诊为精神分裂症和其他精神障碍,很少被误诊为重度抑郁症,更频繁的终生自杀行为,更频繁的住院,抗抑郁药的使用频率较低,更频繁使用抗精神病药和心境稳定剂与BD患者的精神病症状独立相关.将患者分为BDI组和BDII组,我们观察到社会人口统计学和临床因素的显着差异,以及两组之间精神病特征的临床人口学相关性。
    结论:BD+和BD-患者的临床因素差异显示出跨文化一致性,但是精神病特征的临床人口学相关性的结果没有。发现BDI和BDII患者之间存在明显差异。探索BD精神病特征的未来工作需要考虑诊断类型和文化差异。
    背景:这项研究于2013年1月18日首次在ClinicalTrials.gov(https://clinicaltrials.gov/)的网站上注册。它的注册号是NCT01770704。
    Psychotic symptoms are prevalent in patients with bipolar disorder (BD). However, nearly all previous studies on differences in sociodemographic and clinical factors between patients with (BD P +) and without (BD P-) psychotic symptoms were conducted in Western populations, and limited information is known in China.
    A total of 555 patients with BD from seven centers across China were recruited. A standardized procedure was used to collect patients\' sociodemographic and clinical characteristics. The patients were divided into BD P + or BD P- groups based on the presence of lifetime psychotic symptoms. Mann-Whitney U test or chi-square test was used to analyze differences in sociodemographic and clinical factors between patients with BD P + and BD P-. Multiple logistic regression analysis was conducted to explore factors that were independently correlated with psychotic symptoms in BD. All the above analyses were re-conducted after the patients were divided into BD I and BD II group according to their types of diagnosis.
    A total of 35 patients refused to participate, and the remaining 520 patients were included in the analyses. Compared with patients with BD P-, those with BD P + were more likely to be diagnosed with BD I and mania/hypomania/mixed polarity in the first mood episode. Moreover, they were more likely to be misdiagnosed as schizophrenia than major depressive disorder, were hospitalized more often, used antidepressants less frequently, and used more antipsychotics and mood stabilizers. Multivariate analyses revealed that diagnosis of BD I, more frequent misdiagnosis as schizophrenia and other mental disorders, less frequent misdiagnosis as major depressive disorder, more frequent lifetime suicidal behavior, more frequent hospitalizations, less frequent use of antidepressants, more frequent use of antipsychotics and mood stabilizers were independently correlated with psychotic symptoms in BD. After dividing the patients into BD I and BD II groups, we observed notable differences in sociodemographic and clinical factors, as well as clinicodemographic correlates of psychotic features between the two groups.
    Differences in clinical factors between patients with BD P + and BD P- showed cross-cultural consistency, but results on the clinicodemographic correlates of psychotic features were not. Notable differences between patients with BD I and BD II were found. Future work exploring the psychotic features of BD needs to take types of diagnosis and cultural differences into consideration.
    This study was first registered on the website of the ClinicalTrials.gov ( https://clinicaltrials.gov/ ) on 18/01/2013. Its registration number is NCT01770704.
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  • 文章类型: Journal Article
    尽管治疗方法不断更新,但肝细胞癌(HCC)仍然是无法治愈的恶性肿瘤。基质金属蛋白酶(MMPs)促进HCC的进展;然而,关于MMP在HCC中起主要作用尚无共识。在本研究中,我们分析了肝癌中差异表达的基因,尤其是MMPs,使用癌症基因组图谱数据库与邻近组织进行比较。使用差异表达基因的KEGG富集途径包括细胞外基质-受体相互作用,与MMP相关。我们发现在MMP家族中,与邻近组织相比,只有MMP1,MMP3,MMP8,MMP9,MMP11,MMP12,MMP14,MMP15,MMP20,MMP21和MMP24显着增加。至关重要的是,生存和单变量分析表明,只有MMPs1、9、12和14预测总体生存较差;多变量Cox分析和列线图表明,只有MMP1是HCC的不良预后生物标志物。此外,我们观察到未表征的细胞显着富集,但在HCC组织中巨噬细胞减少。与HCC中巨噬细胞减少一致,MMP1与巨噬细胞呈负相关,但与未表征的细胞呈正相关,表明MMP1的主要生产者是未表征的细胞。此外,MMP1的表达与肝癌的免疫反应呈负相关。一起来看,我们的研究结果表明,MMP1是HCC患者预后不良的主要生物标志物,抗MMP1可能是一种值得深入研究的新疗法.
    Hepatocellular carcinoma (HCC) remains an incurable malignancy despite the treatment methods being continually updated. Matrix metalloproteinases (MMPs) promote the progression of HCC; however, no consensus exists on which MMP plays the predominant role in HCCs. In the present study, we analyzed differentially expressed genes in HCCs, especially MMPs, compared with adjacent tissues using the Cancer Genome Atlas database. The KEGG enrichment pathway using differentially expressed genes included extracellular matrix-receptor interaction, which was correlated with MMPs. We found that among the MMP family, only MMP1, MMP3, MMP8, MMP9, MMP11, MMP12, MMP14, MMP15, MMP20, MMP21, and MMP24 significantly increased in HCCs compared with adjacent tissues. Crucially, survival and univariate analyses indicated that only MMPs 1, 9, 12, and 14 predict poor overall survival; however, multivariate Cox analysis and a nomogram demonstrated that only MMP1 is a poor prognostic biomarker for HCCs. In addition, we observed significant enrichment of uncharacterized cells but decreased macrophages in HCC tissues. Consistent with decreased macrophages in HCCs, MMP1 was negatively associated with macrophages but positively correlated with uncharacterized cells, indicating that the main producer of MMP1 is uncharacterized cells. Furthermore, MMP1 expression was negatively correlated with immune responses of HCCs. Taken together, our findings indicated that MMP1 is a poor and predominant prognostic biomarker for patients with HCC and that anti-MMP1 may be a novel therapy that is worth studying in depth.
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  • 文章类型: Journal Article
    目的:我们旨在通过研究绝经后骨质疏松症(PMOP)的遗传机制来开发预测其发生的基因标记。
    方法:从基因表达综合数据库获得五个数据集。无监督共识聚类分析用于确定新的PMOP亚型。为了确定与PMOP相关的中心基因和核心模块,应用加权基因共表达网络分析(WCGNA)。基因本体富集分析用于探索关键基因的生物学过程。采用Logistic回归单因素分析筛选有统计学意义的变量。使用两种算法来选择重要的PMOP相关基因。采用Logistic回归模型构建PMOP相关基因谱。曲线下的接收机工作特征面积,Harrell的一致性指数,校准图表,和决策曲线分析用于表征PMOP相关基因。然后,定量实时聚合酶链反应(qRT-PCR)用于验证基因签名中PMOP相关基因的表达。
    结果:我们确定了三个与PMOP相关的亚型和四个核心模块。肌肉系统的过程,肌肉收缩,基于肌动蛋白丝的运动在中枢基因中更加活跃。我们获得了与PMOP有关的五个特征基因。我们的分析验证了基因签名具有良好的预测能力和适用性。发现GSE56815队列的结果与早期研究的结果一致。qRT-PCR成果显示临床样品中扩增出RAB2A和FYCO1。
    结论:我们开发并验证的PMOP相关基因特征可以准确预测患者发生PMOP的风险。这些结果可以阐明RAB2A和FYCO1在PMOP的分子机制,并产生新的和改进的处理策略,最终帮助PMOP监测。引用这篇文章:骨关节Res2022;11(8):548-560。
    OBJECTIVE: We aimed to develop a gene signature that predicts the occurrence of postmenopausal osteoporosis (PMOP) by studying its genetic mechanism.
    METHODS: Five datasets were obtained from the Gene Expression Omnibus database. Unsupervised consensus cluster analysis was used to determine new PMOP subtypes. To determine the central genes and the core modules related to PMOP, the weighted gene co-expression network analysis (WCGNA) was applied. Gene Ontology enrichment analysis was used to explore the biological processes underlying key genes. Logistic regression univariate analysis was used to screen for statistically significant variables. Two algorithms were used to select important PMOP-related genes. A logistic regression model was used to construct the PMOP-related gene profile. The receiver operating characteristic area under the curve, Harrell\'s concordance index, a calibration chart, and decision curve analysis were used to characterize PMOP-related genes. Then, quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the expression of the PMOP-related genes in the gene signature.
    RESULTS: We identified three PMOP-related subtypes and four core modules. The muscle system process, muscle contraction, and actin filament-based movement were more active in the hub genes. We obtained five feature genes related to PMOP. Our analysis verified that the gene signature had good predictive power and applicability. The outcomes of the GSE56815 cohort were found to be consistent with the results of the earlier studies. qRT-PCR results showed that RAB2A and FYCO1 were amplified in clinical samples.
    CONCLUSIONS: The PMOP-related gene signature we developed and verified can accurately predict the risk of PMOP in patients. These results can elucidate the molecular mechanism of RAB2A and FYCO1 underlying PMOP, and yield new and improved treatment strategies, ultimately helping PMOP monitoring.Cite this article: Bone Joint Res 2022;11(8):548-560.
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  • 文章类型: Journal Article
    目的:本研究的目的是回顾目前关于青少年特发性脊柱侧凸(AIS)的曲线类型和形态有关曲线进展风险的证据。
    方法:由PubMed的两名独立审稿人进行了全面搜索,Embase,Medline,和WebofScience获取有关AIS进展的形态学预测因子的所有已发布信息。搜索项目包括“青少年特发性脊柱侧弯”,\'进展\',和\'成像\'。仔细定义了纳入和排除标准。使用“预后研究质量”工具评估研究偏倚的风险,每个预测因子的证据水平用建议分级进行评级,评估,开发和评估(等级)方法。总之,确定了6,286种出版物,其中3,598种受到二次审查。最终,本综述包括26篇出版物(25个数据集)。
    结果:对于无支架的患者,发现了Cobb角和曲线类型作为预测因子的高和中等证据,分别。初始Cobb角>25°和胸曲线可预测曲线进展。对于有支撑的病人,柔韧性<28%和有限的支架内矫正是预测进展的因素,有高证据和中等证据,分别。胸廓曲线,高根尖椎体旋转,大的肋骨椎骨角度差,凸侧的小肋骨椎骨角度,低骨盆倾斜作为曲线进展的预测因子的证据薄弱。
    结论:对于曲线进展,对于Cobb角已经找到了有力且一致的证据,曲线类型,灵活性,和修正率。发现Cobb角>25°和柔韧性<28%是指导临床预后的重要阈值。尽管证据不足,根尖椎体旋转,肋骨形态,骨盆倾斜可能是有希望的因素。引用本文:骨关节J2022;104-B(4):424-432。
    OBJECTIVE: The aim of this study was to review the current evidence surrounding curve type and morphology on curve progression risk in adolescent idiopathic scoliosis (AIS).
    METHODS: A comprehensive search was conducted by two independent reviewers on PubMed, Embase, Medline, and Web of Science to obtain all published information on morphological predictors of AIS progression. Search items included \'adolescent idiopathic scoliosis\', \'progression\', and \'imaging\'. The inclusion and exclusion criteria were carefully defined. Risk of bias of studies was assessed with the Quality in Prognostic Studies tool, and level of evidence for each predictor was rated with the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. In all, 6,286 publications were identified with 3,598 being subjected to secondary scrutiny. Ultimately, 26 publications (25 datasets) were included in this review.
    RESULTS: For unbraced patients, high and moderate evidence was found for Cobb angle and curve type as predictors, respectively. Initial Cobb angle > 25° and thoracic curves were predictive of curve progression. For braced patients, flexibility < 28% and limited in-brace correction were factors predictive of progression with high and moderate evidence, respectively. Thoracic curves, high apical vertebral rotation, large rib vertebra angle difference, small rib vertebra angle on the convex side, and low pelvic tilt had weak evidence as predictors of curve progression.
    CONCLUSIONS: For curve progression, strong and consistent evidence is found for Cobb angle, curve type, flexibility, and correction rate. Cobb angle > 25° and flexibility < 28% are found to be important thresholds to guide clinical prognostication. Despite the low evidence, apical vertebral rotation, rib morphology, and pelvic tilt may be promising factors. Cite this article: Bone Joint J 2022;104-B(4):424-432.
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  • 文章类型: Journal Article
    肾综合征出血热(HFRS),一种啮齿动物传播的疾病,是发达国家和发展中国家的主要公共卫生问题。中国是世界上流行最严重的国家,占90%的病例。尽管我国大部分地区的HFRS发病率有明显下降,HFRS在一些疫区已明显反弹。宣城就是这些地区之一。在这项研究中,我们收集了宣城市最近报道的病例数据,并设计了1:3病例对照研究。卡方检验,进行单因素和多因素logistic回归分析.在所有情况下,农民占职业的比例最高。有20个具有统计学意义的变量,包括室内卫生条件;周围环境;是否在工作中被老鼠咬伤等标准。此外,暴露于啮齿动物和大鼠叮咬是HFRS的高风险因素。啮齿动物密度计算为20.9%(159/760),病毒携带率为9.4%(15/159),携带病毒的大鼠指数约为2.0%。暴露于啮齿动物和昆虫叮咬也是宣城当地居民发生HFRS的高危因素。更重要的是,在洪水年代,啮齿动物密度的增加导致人类暴露于啮齿动物的风险增加。正如我们的统计分析所证明的那样,应制定和实施有针对性的策略,以减少未来当地疾病的发生率。
    Haemorrhagic fever with renal syndrome (HFRS), a rodent-borne disease, is a major public health concern in both developed and developing countries. China is the most severe endemic country in the world, constituting 90% of the cases. Although the incidence of HFRS has substantively decreased in most areas of China, HFRS has rebounded remarkably in some epidemic areas. Xuancheng is one of these areas. In this study, we collected the case data reported recently in Xuancheng and designed a 1:3 case-control study. The Chi-square test, univariate and multivariate logistic regression analysis were performed. In all cases, farmers made up the highest proportion of occupations. And there were 20 variables with statistical significance including indoor hygienic conditions; the surrounding environment; whether bitten by rats at work and other criteria. In addition, exposure to rodents and rats bites is a high-risk factor for HFRS. Rodent density was calculated at 20.9% (159/760), the virus carrier rate was 9.4% (15/159) and the index of rats with a virus was about 2.0%. Exposure to rodents and insect bites is also high-risk factors for HFRS among local residents in Xuancheng. More importantly, during the flood years, the increased density of rodents led to an increased risk of human exposure to rodents. As our statistical analysis proves, targeted strategies should be developed and implemented to reduce the incidence of local diseases in the future.
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  • 文章类型: Journal Article
    BACKGROUND: Neuroendocrine tumors (NETs) frequently occur in the gastrointestinal tract, lung, and pancreas, and the rectum and appendix are the sites with the highest incidence. Epidemiology statistics show that an estimated 8000 people every year in the United States are diagnosed with NETs occurring in the gastrointestinal tract, including the stomach, intestine, appendix, colon, and rectum. The pathological changes and clinical symptoms of NETs are not specific, and therefore they are frequently misdiagnosed.
    OBJECTIVE: To investigate the clinical symptoms, pathological characteristics, treatment, and prognosis of rectal neuroendocrine tumors (RNETs) by analyzing the clinical and pathological data of 132 RNET cases at our hospital.
    METHODS: All RNETs were graded according to Ki-67 positivity and mitotic events. The tumors were staged as clinical stages I, II, III, and IV according to infiltrative depth and tumor size. COX proportional hazard model was used to assess the main risk factors for survival.
    RESULTS: These 132 RNETs included 83 cases of G1, 21 cases of G2, and 28 cases of G3 (neuroendocrine carcinoma) disease. Immunohistochemical staining showed that 89.4% of RNETs were positive for synaptophysin and 39.4% positive for chromogranin A. There were 19, 85, 23, and 5 cases of clinical stages I, II, III, and IV, respectively. The median patient age was 52.96 years. The diameter of tumor, depth of invasion, and pathological grade were the main reference factors for the treatment of RNETs. The survival rates at 6, 12, 36, and 60 mo after operation were 98.5%, 94.6%, 90.2%, and 85.6%, respectively. Gender, tumor size, tumor grade, lymph node or distant organ metastasis, and radical resection were the main factors associated with prognosis of RNETs. Multivariate analysis showed that tumor size and grade were independent prognostic factors.
    CONCLUSIONS: The clinical symptoms of RNETs are not specific, and they are easy to misdiagnose. Surgery is the main treatment method. The grade and stage of RNETs are the main indices to evaluate prognosis.
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  • 文章类型: Journal Article
    OBJECTIVE: To summarize the epidemiological characteristics of patients following surgery for spinal metastases retrospectively and make a univariate analysis to identify independent variables that could affect the operation decision making.
    METHODS: This was a multicenter retrospective review of patients with spinal metastasis who were treated with surgery from 1 January 2007 to 31 July 2019. Basic clinical data were analyzed retrospectively by univariate analysis to identify independent variables that could affect the decision of operation modalities, including gender, age, spinal metastatic site, Frankel score, Karnofsky performance score (KPS), spinal instability neoplastic score (SINS), visual analogue scale (VAS), Tokuhashi score, urinary and fecal incontinence, spinal pathological fracture, primary tumor, extraspinal metastasis, visceral metastasis, and bone lesion (osteolytic, osteoblastic or mixed).
    RESULTS: A total of 580 patients including 332 males and 248 females were enrolled in the study with an average age of 58.26 years old (range, 13-86 years old). The most common spinal metastatic level was the thoracic vertebra (190 [32.76%]), followed by the lumbar vertebra (146 [25.17%]), cervical vertebra (47 [8.10%]), and sacral vertebra (35 [6.03%]). Metastases involving more than two sites of the cervical, thoracic, lumbar, and sacral vertebrae arose in 162 (27.93%) patients. For primary tumor, there were 198 (34.14%) cases of lung cancer, 41 (7.07%) cases of kidney cancer, 39 (6.72%) cases of breast cancer, 38 (6.55%) cases of gastrointestinal cancer, 35 (6.03%) cases of lymphoma and myeloma, 25 (4.31%) cases of prostate cancer, 24 (4.14%) cases of liver cancer, 23 (3.97%) cases of mesenchymal tissue sarcoma, 20 (3.45%) cases of thyroid cancer, and 84 (14.48%) cases were tumor with unknown origin. Sixty-three (10.86%) patients received minimally invasive surgery, 460 (79.31%) patients received palliative surgery, and the remaining 57 (9.83%) received tumor resection. According to the univariate analysis, the KPS score, SINS score, VAS score, Tokuhashi score, urinary and fecal incontinence, spinal pathological fracture, and bone lesion (osteolytic, osteoblastic or mixed) were independent and favorable factors affecting the surgery modalities.
    CONCLUSIONS: Surgical treatment for spinal metastases was mainly to relieve pain, rebuild spinal stability, improve nerve function, control local tumors, and improve the quality of life of patients. For middle-aged and elderly patients with good general conditions, severe pain, spinal pathological fracture, spine instability and without urinary and fecal incontinence, early surgical treatment should be actively carried out.
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  • 文章类型: Journal Article
    Recent developments in psychoradiological researches have highlighted the disrupted organization of large-scale functional brain networks in obsessive-compulsive disorder (OCD). However, whether abnormal activation of localized brain areas would affect network dysfunction remains to be fully characterized. We applied both univariate analysis and multivariate pattern analysis (MVPA) approaches to investigate the abnormalities of regional homogeneity (ReHo), an index to measure the localized connectivity, in 88 medication-free patients with OCD and 88 healthy control subjects (HCS). Resting-state functional magnetic resonance imaging (RS-fMRI) data of all the participants were acquired in a 3.0-T scanner. First, we adopted a traditional univariate analysis to explore ReHo alterations between the patient group and the control group. Subsequently, we utilized a support vector machine (SVM) to examine whether ReHo could be further used to differentiate patients with OCD from HCS at the individual level. Relative to HCS, OCD patients showed lower ReHo in the bilateral cerebellum and higher ReHo in the bilateral superior frontal gyri (SFG), right inferior parietal gyrus (IPG), and precuneus [P < 0.05, family-wise error (FWE) correction]. ReHo value in the left SFG positively correlated with Yale-Brown Obsessive Compulsive Scale (Y-BOCS) total score (r = 0 0.241, P = 0.024) and obsessive subscale (r = 0.224, P = 0.036). The SVM classification regarding ReHo yielded an accuracy of 78.98% (sensitivity = 78.41%, specificity = 79.55%) with P < 0.001 after permutation testing. The most discriminative regions contributing to the SVM classification were mainly located in the frontal, temporal, and parietal regions as well as in the cerebellum while the right orbital frontal cortex was identified with the highest discriminative power. Our findings not only suggested that the localized activation disequilibrium between the prefrontal cortex (PFC) and the cerebellum appeared to be associated with the pathophysiology of OCD but also indicated the translational role of the localized connectivity as a potential discriminative pattern to detect OCD at the individual level.
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  • 文章类型: Journal Article
    Dual-pulse laser-induced breakdown spectroscopy (DPLIBS) and chemometric methods were used to predict chromium content in rice leaves, along with the purpose for increasing the detection sensitivity and accuracy. The influence of important parameters in DPLIBS were investigated and optimized. Then, partial least square (PLS) was used to establish chromium content prediction models, and the value of regression coefficient based on PLS was applied to determine feature variables. In addition, multivariate and univariate analysis were used to verify the modeling performance of selected feature variables. The results indicated that support vector machine model based on feature variables achieved the best performance, with correlation coefficient of 0.9946, root mean square error of 4.85 mg/kg and residual predictive deviation of 9.70 in prediction set. The proposed method provides a high-accuracy and fast approach for chromium content prediction in rice leaves, which could potentially be used for toxic and nutrient elements detection in food.
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  • 文章类型: Journal Article
    重金属的快速检测对于保证农作物的质量和安全非常重要。激光诱导击穿光谱(LIBS),再加上单变量和多变量分析,应用于三种大米中铜的定量分析(江苏大米,普通米饭,和四妙米)。对于单变量分析,采用了三种预处理方法来减少波动,包括背景归一化,内标法,和标准正态变量(SNV)。线性回归模型显示光谱强度与Cu含量之间有很强的相关性,R2大于0.97。检测限(LOD)约为5ppm,低于食品中铜的耐受极限。对于多变量分析,偏最小二乘回归(PLSR)在提取有效信息进行预测方面显示出其优势,其灵敏度达到1.95ppm,虽然支持向量机回归(SVMR)在校准集和预测集中都表现得更好,其中Rc2和Rp2分别达到0.9979和0.9879。这项研究表明,LIBS可以被认为是定量大米中铜污染的建设性工具。
    Fast detection of heavy metals is very important for ensuring the quality and safety of crops. Laser-induced breakdown spectroscopy (LIBS), coupled with uni- and multivariate analysis, was applied for quantitative analysis of copper in three kinds of rice (Jiangsu rice, regular rice, and Simiao rice). For univariate analysis, three pre-processing methods were applied to reduce fluctuations, including background normalization, the internal standard method, and the standard normal variate (SNV). Linear regression models showed a strong correlation between spectral intensity and Cu content, with an R 2 more than 0.97. The limit of detection (LOD) was around 5 ppm, lower than the tolerance limit of copper in foods. For multivariate analysis, partial least squares regression (PLSR) showed its advantage in extracting effective information for prediction, and its sensitivity reached 1.95 ppm, while support vector machine regression (SVMR) performed better in both calibration and prediction sets, where R c 2 and R p 2 reached 0.9979 and 0.9879, respectively. This study showed that LIBS could be considered as a constructive tool for the quantification of copper contamination in rice.
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