Category: Statistics

Huan Jing Ke Xue. 2023 Feb 8;44(2):807-815. doi: 10.13227/j.hjkx.202204212.

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs), as a highly toxic persistent organic pollutant, are commonly found in soil and water environments. In recent years, the pollution of PAHs in groundwater has attracted wide attention from scientists. To study the pollution characteristics and sources of polycyclic aromatic hydrocarbon in groundwater of the coking site, 16 PAHs priorly controlled by the US EPA were analyzed and discussed. In this study, we identified the contamination characteristics of PAHs in groundwater, analyzed the pollution sources of PAHs, and evaluated the ecological risk of PAHs in the coking site by combining statistical techniques, the positive matrix factorization (PMF) model, and risk quotient (RQ) methods. The results indicated that the total detection rate of PAHs in groundwater of the coking plant was 46.7%. The concentrations of PAHs in groundwater of the coking plant ranged from below the detection limit to 444.9 μg·L^-1, with the average value of 1.88 μg·L^-1. The concentration of PAHs in the groundwater of different production workshops was significantly different. The most polluted workshop was in the tar-refining area, and the concentration of 16 PAHs was 444.9 μg·L^-1. Based on the PMF model, we identified the two primary contamination sources of PAHs in groundwater of the coking plant:① oil combustion and ② coal and biomass combustion and oil leakage. The contribution ratios of the two sources to PAHs of groundwater were 38.6% and 61.4%, respectively. The results of the ecological risk assessment indicated that Σ₁₆PAHs in groundwater of the coking plant had high ecological risk, and the ecological risk of single PAHs in 53.4% of the groundwater sampling site was at a high ecological risk level. In conclusion, it is urgent to carry out the treatment and restoration of the groundwater environment in the coking plant site.

PMID:36775604 | DOI:10.13227/j.hjkx.202204212

Huan Jing Ke Xue. 2023 Feb 8;44(2):796-806. doi: 10.13227/j.hjkx.202203144.

ABSTRACT

In order to explore the sources of pollution and health risk profile of heavy metal elements in groundwater, 41 sets of representative groundwater samples from the southwest sub-basin of the Shiqi River were examined for 10 heavy metal elements (As, Cr, Cd, Al, Cu, Zn, Ni, Co, Mn, and Hg), and correlation analysis and principal component analysis were used to resolve the possible sources of heavy metal contamination in groundwater in the study area. The concentration characteristics and health risk levels of the 10 heavy metals were assessed using the single-factor contamination index (P_i), the Nemerow comprehensive contamination index (P_N), and the health risk model. The results showed that:① the average values of heavy metal elements of the groundwater in the study area all met the limit of the class Ⅲ water standard in the quality standard for groundwater (GB/T 14848-2017); only the maximum value of Al was exceeded, followed by a large variation in the concentrations of Al, Mn, and Cr. The heavy metal element with the largest average contribution was Al (65.74%). ② The results of the single-factor contamination index evaluation showed that only the heavy metal element Al exceeded the cleaning level, and the results of the Nemerow comprehensive contamination index evaluation showed that the study area was basically at low pollution levels, and the quality of groundwater was good. ③ The results of the multivariate statistical analysis showed that Zn, Co, and Mn were from mixed sources consisting of geological formation and domestic waste; Al, As, and Cu were from agricultural sources; Cd, Cr, and Ni were from industrial sources; and Hg came from long-range atmospheric transport. ④ The health risk values for all heavy metals in the study area were within acceptable limits, with higher health risk values for children than for adults from the drinking water route, lower health risk values than in adults from the dermal route, and higher health risk values for heavy metals from the drinking water route than those from the dermal route, indicating that the drinking water route was the main route of exposure to heavy metals.

PMID:36775603 | DOI:10.13227/j.hjkx.202203144

Huan Jing Ke Xue. 2023 Feb 8;44(2):752-760. doi: 10.13227/j.hjkx.202204232.

ABSTRACT

Global warming and regional extreme climates will lead to unbalanced rainfall, melting glaciers, and permafrost degradation in alpine and arid mountain plains, thereby changing the regional hydrological cycle. The relationship between surface water and groundwater conversion is one of the important scientific issues of hydrological cycle climate response in alpine arid areas. Taking the Datong River Basin at the southern foot of the Qilian Mountains as the study area, based on 119 sets of basic hydrochemical parameters and deuterium-oxygen isotope data, using multivariate statistical analysis and isotopic techniques, the hydrochemical characteristics of surface water and groundwater in the basin and their mutual transformation process were studied. The results showed that the surface water was HCO₃-Mg·Ca type, which was mainly controlled by rock weathering, whereas the groundwater was HCO₃-Mg·Ca type and Cl·SO₄-Na type, which was controlled by rock weathering and evaporation concentration. There was a small amount of calcium and magnesium feldspar dissolved in the upstream groundwater, and the chemical components of the midstream groundwater were mainly the weathering and dissolution of carbonate rocks. The contribution rates of weathering filtration, anthropogenic activities, native sedimentary environment, alternating adsorption of cations, and other factors to the chemical components of surface water and groundwater in the study area were 39.1%, 15.0%, 12.6%, 13.8%, and 19.5%, respectively. The deuterium and oxygen isotope contents of Datong River water showed a trend of enrichment to depletion along the groundwater flow direction. The δD and δ¹⁸O isotope test results showed that the deuterium and oxygen isotope content in the Datong River along the groundwater flow showed a trend of enrichment to depletion. The upper and middle reaches of the Datong River were mainly recharged by atmospheric precipitation, whereas the lower reaches were affected by geological structure and influenced by hydrogeological conditions, which was mainly due to diving and spring water overflow to supply river water, as the discharge area of groundwater.

PMID:36775599 | DOI:10.13227/j.hjkx.202204232

Huan Jing Ke Xue. 2023 Feb 8;44(2):740-751. doi: 10.13227/j.hjkx.202204313.

ABSTRACT

Tuochangjiang River is a typical mining-type watershed in the karst mountainous area of western Guizhou province. The study of its hydrochemical evolution characteristics and driving factors is of great significance to the local economic development and the scientific management of water resources. The samples of river water, spring water, and mine water in the Tuochangjiang River Basin were collected, and the sources of solutes and their contribution to the chemical components of river water were discussed by means of hydrochemical diagrams, mathematical statistics, and the absolute principal component scores-multivariate linear regression model (APCS-MLR). The results showed that the pH of the river water ranged between 7.30 to 8.31, and the TDS value ranged between 40 to 520 mg·L^-1, which was mainly contributed by Ca²⁺, Na⁺, HCO₃^–, and SO₄^2-. The dominant cations in river water were Ca²⁺ and Na⁺, the dominant anions were HCO₃^– and SO₄^2-, and the main water chemistry transitioned from HCO₃-Ca to HCO₃-Ca·Na and HCO₃·SO₄-Ca·Na type, whereas that of the mine water was mainly the HCO₃-Na and HCO₃·SO₄-Na types. The chemical composition of river water was affected by rock weathering, exchange adsorption of anions, mineral dissolution and precipitation, and human activities, in which Ca²⁺, Mg²⁺, and HCO₃^– were mainly derived from the weathering and dissolution of carbonate and silicate rocks, Na⁺and SO₄^2- were mainly from the discharge of mining wastewater, and Cl^– and NO₃^– were affected by domestic sewage and agricultural activities, respectively. APCS-MLR analysis further showed that the river water solutes mainly included five sources:discharge of mining wastewater, dissolution of soil minerals, geological background, agricultural activities, and unknown sources, and their contribution rates to river water were 23.49%, 35.04%, 13.87%, 7.96%, and 20.63%, respectively. Mining factors and soil factors were the most important sources of solutes in the river water, and they were the main driving factors for the hydrochemical evolution of the Tuochangjiang River Basin.

PMID:36775598 | DOI:10.13227/j.hjkx.202204313

J Bodyw Mov Ther. 2023 Jan;33:8-13. doi: 10.1016/j.jbmt.2022.09.005. Epub 2022 Sep 23.

ABSTRACT

INTRODUCTION: Core strengthening, balance, and flexibility programs such as Pilates have been advocated to positively impact running mechanics and prevent lower extremity injuries. The purpose of this study was to assess the effects of a 12-week mat-based Pilates exercise program on dynamic knee valgus alignment in runners.

METHODS: Thirty-four novice runners, including young male and female adults performed a running protocol at baseline. The protocol consisted of the participants running on a treadmill at a constant five miles per hour (mph) for 4 min. Post-examination, participants were randomly assigned to a Pilates or control group (n = 16 and n = 18, respectively). A certified Pilates instructor gave the Pilates group a 12-week home-based program. To ensure participants in the Pilates group performed exercises correctly, the Pilates instructor conducted the first session, and provided feedback to each participant. Participants in both groups performed the same running testing protocol every four weeks. Knee valgus was measured as the medial displacement of the knee joint center during the running stance phase. Repeated measures Analysis of Variance (RepANOVA) was calculated at baseline and 4-, 8-, and 12-weeks post examinations to compare knee valgus during running.

RESULTS: Although a reduction in dynamic knee valgus was observed within the Pilates group, the RepANOVA analysis revealed this change was not statistically significant.

CONCLUSIONS: Pilates mat-based exercises may improve knee valgus after 12 weeks but a larger sample size, longer intervention duration, or a supervised program should be considered for future research to evaluate its effectiveness.

PMID:36775530 | DOI:10.1016/j.jbmt.2022.09.005

Nanotoxicology. 2023 Feb 12:1-22. doi: 10.1080/17435390.2023.2175735. Online ahead of print.

ABSTRACT

Inhalation of nanoparticles emitted from toner-based printing equipment (TPE), such as laser printers and photocopiers, also known as PEPs, has been associated with systemic inflammation, hypertension, cardiovascular disease, respiratory disorders, and genotoxicity. Global serum metabolomics analysis in 19 healthy TPE operators found 52 dysregulated biomolecules involved in upregulation of inflammation, immune, and antioxidant responses and downregulation of cellular energetics and cell proliferation. Here, we build on the metabolomics study by investigating the association of a panel of nine urinary OS biomarkers reflecting DNA/RNA damage (8OHdG, 8OHG, and 5OHMeU), protein/amino acid oxidation (o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine), and lipid oxidation (8-isoprostane, 4-hydroxy nonenal, and malondialdehyde [MDA]), as well as plasma total MDA and total protein carbonyl (TPC), with several nanoparticle exposure metrics in the same 19 healthy TPE operators. Plasma total MDA, urinary 5OHMeU, 3-chlorotyrosine, and 3-nitrotyrosine were positively, whereas o-tyrosine inversely and statistically significantly associated with PEPs exposure in multivariate models, after adjusting for age and urinary creatinine. Urinary 8OHdG, 8OHG, 5OHMeU, and total MDA in urine and plasma had group mean values higher than expected in healthy controls without PEPs exposure and comparable to those of workers experiencing low to moderate levels of oxidative stress (OS). The highest exposure group had OS biomarker values, most notably 8OHdG, 8OHG, and total MDA, that compared to workers exposed to welding fumes and titanium dioxide. Particle number concentration was the most sensitive and robust exposure metric. A combination of nanoparticle number concentration and OS potential of fresh aerosols is recommended for larger scale future studies.

PMID:36774544 | DOI:10.1080/17435390.2023.2175735

BMC Sports Sci Med Rehabil. 2023 Feb 11;15(1):19. doi: 10.1186/s13102-023-00629-z.

ABSTRACT

BACKGROUND: Relative age effect (RAE) is a concept related to the possible advantage that older athletes would have over younger ones within the same category. Although many studies have approached this subject in individual sports, there are few clippings by events within the sport. More detailed analyses are necessary for a better understanding of how RAE behaves in sports, especially in athletics, the subject of this study. The objective of this study was to analyze the RAE on speed in track and field events as a whole, separating the flat races from the hurdles races.

METHODS: The Brazilian Ranking of Brazilian Athletics Confederation was used for data analysis, and the sample was composed of the 50 best-placed marks in the ranking of speed events in athletics in the categories Under(U)-16 and U-18 (female and male). Statistical analysis was calculated by chi-square, and the effect size was checked by Cramer’s V. Likelihood-ratio test (L-Ratio) assessed the probability of the RAE occurring in the total sample and by age groups.

RESULTS: In the total sample the results pointed to the emergence of RAE in males in both categories (U-16: p < 0.001; V: 0.13; L-Ratio: 3.64, U-18: p < 0.001; V: 0.13; L-Ratio: 3.80), whereas in females no such effect was found in any category (U-16: p = 0.6; V: 0.09; L-Ratio: 0.09, U-18: p = 0.6; V: 0.07; L-Ratio: 0.12). When the results were separated by type of event, there was only a RAE in the shallow event in the U-18 female category (p = 0.3; V: 0.11; L-Ratio: 8.72).

CONCLUSION: The results allow us to conclude that there is a RAE in the speed trials of Brazilian athletics in the U16 and U18 categories for men, while this effect appears only in the shallow trials of the U18 category for women, indicating that the RAE has incidence when there is more participation and competition in the sport.

PMID:36774525 | DOI:10.1186/s13102-023-00629-z

J Otolaryngol Head Neck Surg. 2023 Feb 11;52(1):12. doi: 10.1186/s40463-022-00611-8.

ABSTRACT

BACKGROUND: Genomic testing has enhanced pre-surgical decision making for cytologically indeterminate thyroid nodules, but there remains uncertainty regarding RAS mutations. The addition of extra genetic alterations to previous driver mutation panels has been shown to improve predictive value. This study aims to evaluate the relationship between the mutant allele frequency (AF) and likelihood of malignancy in thyroid nodules with RAS mutations.

METHODS: A retrospective cohort review was performed evaluating patients with indeterminate cytology (Bethesda categories III, IV and V) and ThyroSeq® v3 testing demonstrating a RAS mutation, who underwent surgery. Univariate and multivariate regression analyses were used to evaluate relationships between AF, other genetic alterations, and malignancy.

RESULTS: Thirty-nine patients met criteria, 77% of the thyroid nodules (30/39) were found to be malignant. None demonstrated aggressive pathology. On univariate regression, there was no relationship between AF and likelihood of malignancy. There was, however, a significant correlation between AF and the rate of an additional genetic alteration. Multivariate analysis found a trend between RAS, a second genetic alteration and malignancy, but it did not reach statistical significance.

CONCLUSIONS: There was no direct relationship between the level of allelic frequency in thyroid nodules expressing RAS mutations and the likelihood of malignancy. There was a statistically significant relationship between increasing AF and the presence of a second genetic abnormality, suggesting a possible progression from initial driver mutation and then a second genetic alteration prior to malignant transformation.

PMID:36774522 | DOI:10.1186/s40463-022-00611-8

BMC Med Educ. 2023 Feb 11;23(1):107. doi: 10.1186/s12909-023-04078-7.

ABSTRACT

BACKGROUND: The quality of nursing care in different healthcare contexts can be associated with the level of available nursing competence. Physical assessment skills are vital in nurses’ assessment of patient care needs. However, in nursing education, using physical assessment skills is challenging for nursing students who struggle to apply these skills comprehensively in a clinical rotation. Therefore, this study explores changes in nursing competence, factors associated with changes after clinical rotations, and whether a Suite of Mobile Learning Tools supports changes in confident use of basic physical assessment skills.

METHODS: A quantitative cohort study with an explorative pre-and post-test design. During autumn 2019 and spring 2020, 72 s-year nursing students and 99 third-year students participated in the study. The Nurse Professional Competence scale short form was used to investigate students’ self-reported changes in nursing competence, and a study-specific questionnaire was used to investigate students’ confidence concerning performing physical assessments. The students voluntarily used the Suite of Mobile Learning Tools for the learning of physical assessment. Linear regression analysis was used to identify factors associated with changes in nursing competence after clinical rotation. The STROBE guidelines for cohort studies were followed for study reporting.

RESULTS: After the clinical rotation, both student groups reported changes in nursing competence and confidence in performing physical assessment skills, with statistically significant moderate or large changes in all areas. The Suite of Mobile Learning Tools was evaluated as being useful for learning physical assessment. The regression analysis showed that confidence in performing physical assessment skills, the usefulness of the Suite of Mobile Learning Tools, and a higher nursing competence at the start of clinical rotation were positively associated with overall nursing competence.

CONCLUSION: Basic physical assessment skills are an important component of nursing competence and can be considered one of the pillars of person-centered care, as proposed by the Fundamentals of Care framework. Spaced repetition and access to digital resources are suggested pedagogical approaches to enhance student confidence in the use of assessment skills within academic and clinical contexts.

PMID:36774493 | DOI:10.1186/s12909-023-04078-7

BMC Public Health. 2023 Feb 11;23(1):311. doi: 10.1186/s12889-023-15058-3.

ABSTRACT

BACKGROUND: Maintaining healthy eating habits among children is challenging due to industrial tactics. There is little research on the effect of nutritional labels and tv ads on the eating habits of children. So the primary aim of the study was to explore the noticeability of the food packaging labels by the children, the information retrieved from the food nutrition labels, and their role in increased frequency of eating out in addition to the perceptions of their parents about the television ads.

METHODS: A cross-sectional study was conducted at schools in Punjab, India. Using multi-stage stratified random sampling, we included 722 school-going children aged 14-18 and their parents. A structured predefined questionnaire collected data using a four-point Likert scale. Descriptive statistics and binary logistic regression were used to draw our inferences.

RESULTS: About 46% of children were eating out > 3 times a week. Nearly 49% said they never looked at the expiry dates on the food packet, and 40% have yet to notice the quality certification. Nearly half do not understand the components of the food label, and 59% said they never changed their buying behavior because of the label. Only 37% of parents expressed their concerns about the timing of the ads when children watch television, while only 25.5% were concerned about the accuracy of the information. Concerns of the parents regarding the timing of the ads, and celebrity endorsements, were potential predictors for the increased frequency of eating out by the children.

CONCLUSIONS: Low awareness regarding the utility of nutrition labels and minimal concerns of the parents increase the frequency of eating out. Unification of our existing policies regarding food labels and tv advertisements to develop family-centric interventions will bring us one step closer to improving the enabling environment to curb the growing menace of childhood obesity.

PMID:36774475 | DOI:10.1186/s12889-023-15058-3