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Nevin Manimala Statistics

Sorption of tetracycline onto hexabromocyclododecane/polystyrene composite and polystyrene microplastics: Statistical physics models, influencing factors, and interaction mechanisms

Environ Pollut. 2021 Apr 15;284:117164. doi: 10.1016/j.envpol.2021.117164. Online ahead of print.

ABSTRACT

Microplastics (MPs) are becoming a major concern due to their great potential to sorb and transport pollutants in the aquatic environment; hexabromocyclododecane (HBCD) is a common chemical additive in polystyrene (PS) MPs. However, the underlying mechanisms for the interaction of tetracycline (TC) onto HBCD-PS composites MPs (HBCD-PS MPs) are still not well documented. Our findings showed that the addition of HBCD resulted in a relatively higher hydrophobicity of PS MPs, and significantly enhanced the sorption ability of HBCD-PS MPs for TC. The kinetic models suggested that the sorption of TC onto PS and HBCD-PS MPs were mainly controlled by film diffusion and intra-particle diffusion, respectively. The statistical physics models were used to elucidate the sorption of TC onto PS and HBCD-PS MPs was associated with the formation of the monolayer, and the results indicated the TC was sorbed onto the two MPs by both multi-molecular and non-parallel processes. The TC sorption was solution pH-dependent while the effect of NaCl content on TC sorption was negligible. The presence of Cu(Ⅱ), Pb(Ⅱ), Cd(Ⅱ), and Zn(Ⅱ) ions had different influences on the TC sorption onto both the MPs. Overall, various mechanisms including π-π and hydrophobic interactions jointly regulated the sorption of TC onto both the MPs. Our results provided new insights into the sorption behavior and interaction mechanisms of TC onto both the MPs and highlighted that the addition of HBCD likely increased the enrichment capacity of MPs for pollutants in the environment.

PMID:33894538 | DOI:10.1016/j.envpol.2021.117164

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Nevin Manimala Statistics

Real-time in vitro measurement of denture-mucosa pressure distribution in a typical edentulous patient with and without implants: Development of a methodology

J Mech Behav Biomed Mater. 2021 Apr 16;119:104531. doi: 10.1016/j.jmbbm.2021.104531. Online ahead of print.

ABSTRACT

PURPOSE: To measure the pressure distribution on the oral mucosa in vitro by comparing the pressure distributions under a complete denture and that of an implant overdenture.

MATERIALS AND METHOD: Anatomically accurate models and conventional Class I complete denture (CD) were produced and subjected to cyclic loading using a 100 N vertical centric and unilateral masticatory load with the universal testing machine (Instron 3369). Four miniature pressure sensors were positioned at four different locations in the intaglio surface of the denture and recorded pressure at 100 Hz frequency measured during a 10-cycle load at 1 Hz. Testing was repeated in different clinical combinations; CD vs. single implant overdentures (1-IOD), CD vs. two, three and four implant overdentures (2-IOD, 3-IOD vs. 4-IOD). The pressure profile (kPa) of complete dentures were measured and compared to the implant overdenture combinations. Collected data was statically analysed using SPSS and one-way analysis of variance.

RESULTS: The highest mean pressure was observed in CD group, with the mean mandible buccal ridge pressure value of 212.82 kPa ± 136.9 due to its surface area. There were no statistically significant differences between the group combinations (p = 0.146) but between various locations in the mean pressure recorded across the five denture/overdenture combinations.

CONCLUSION: CD experienced large pressure values on mandibular denture. 1-IOD demonstrated the most pressure in comparison to CD where with an increase in the number of implants used, it transformed the denture from being pure-borne mucosa to an implant overdenture, providing support and distributing the pressure amongst the implants.

PMID:33894527 | DOI:10.1016/j.jmbbm.2021.104531

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Nevin Manimala Statistics

The association between antimicrobials and the antimicrobial-resistant phenotypes and resistance genes of Escherichia coli isolated from hospital wastewaters and adjacent surface waters in Sri Lanka

Chemosphere. 2021 Apr 17;279:130591. doi: 10.1016/j.chemosphere.2021.130591. Online ahead of print.

ABSTRACT

The presence of antimicrobials, antimicrobial-resistant bacteria (ARB), and the associated antimicrobial resistance genes (ARGs) in the environment is a global health concern. In this study, the concentrations of 25 antimicrobials, the resistance of Escherichia coli (E. coli) strains in response to the selection pressure imposed by 15 antimicrobials, and enrichment of 20 ARGs in E. coli isolated from hospital wastewaters and surface waters were investigated from 2016 to 2018. In hospital wastewaters, clarithromycin was detected at the highest concentration followed by sulfamethoxazole and sulfapyridine. Approximately 80% of the E. coli isolates were resistant, while 14% of the isolates exhibited intermediate resistance against the tested antimicrobial agents. Approximately 61% of the examined isolates were categorized as multidrug-resistant bacteria. The overall abundance of phenotypes that were resistant toward drugs was in the following order: β-lactams, tetracycline, quinolones, sulfamethoxazole/trimethoprim, aminoglycosides, and chloramphenicol. The data showed that the E. coli isolates frequently harbored blaTEM, blaCTX-M, tetA, qnrS, and sul2. These results indicated that personal care products were significantly associated with the presence of several resistant phenotypes and resistance genes, implying their role in co-association with multidrug resistance. Statistical analysis also indicated a disparity specific to the site, treatment, and year in the data describing the prevalence of ARB and ARGs and their release into downstream waters. This study provides novel insights into the abundance of antimicrobial, ARB and ARGs in Sri Lanka, and could further offer invaluable information that can be integrated into global antimicrobial resistance databases.

PMID:33894511 | DOI:10.1016/j.chemosphere.2021.130591

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Nevin Manimala Statistics

The new Austrian indoor radon survey (ÖNRAP 2, 2013-2019): Design, implementation, results

J Environ Radioact. 2021 Apr 21;233:106618. doi: 10.1016/j.jenvrad.2021.106618. Online ahead of print.

ABSTRACT

The delineation of radon prone areas is one of the central requirements of the European Council Directive 2013/59/EURATOM. It is quite a complex task which usually requires the collection of radon data through an appropriate survey as a first step. This paper presents the design and methodology of the recent Austrian radon survey (ÖNRAP 2, 2013-2019) and its implementation. It details the results of the nationwide survey as well as correlations and dependencies with geology and building characteristics. The paper also discusses the representativeness of the survey as well as advantages and disadvantages of the selected approach. For the purpose of establishing a new delineation of radon prone areas in Austria we distributed approximately 75,000 passive long-term radon detectors. They were offered to selected members of the voluntary fire brigades and this resulted in about 50,000 radon measurements. Thus, a return rate of about 67% was achieved. The distribution of the radon results closely follows a log-normal distribution with a median of 99 Bq/m³, a geometric mean of 109 Bq/m³, and a geometric standard deviation factor of 2.29. 11% of the households show a mean radon concentration above the national reference level of 300 Bq/m³. Important data on building characteristics and the location of the measured rooms were collected by means of a specific questionnaire and a measurement protocol that were handed out together with the radon detectors. We were able to identify significant correlations between the indoor radon concentration and geology, the year of construction, and the coupling of the room to the ground (basement yes/no, floor level). Being a geographically-based and not a population-weighted survey, the comparison of building characteristics with the Austrian census data confirms that rural areas are over-represented in this survey. As a summary, the selected approach of conducting passive long-term radon measurements in selected dwellings of members of the voluntary fire brigades proved to be an efficient method to collect reliable data as a basis for the delineation of radon prone areas. The next step was to eliminate factors that influence the measured radon concentration through appropriate modelling. Based on the results predicted by the model radon areas are then be classified. This will be presented in a subsequent publication.

PMID:33894497 | DOI:10.1016/j.jenvrad.2021.106618

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Nevin Manimala Statistics

Short Communication: Interim toxicity analysis for patients with limited stage small cell lung cancer (LSCLC) treated on CALGB 30610 (Alliance) / RTOG 0538

Lung Cancer. 2021 Apr 18;156:68-71. doi: 10.1016/j.lungcan.2021.04.016. Online ahead of print.

ABSTRACT

INTRODUCTION: The CALGB 30610/RTOG 0538 randomized trial was designed to test whether high-dose thoracic radiotherapy (TRT) would improve survival compared with 45 Gy twice-daily (BID) TRT in limited stage small cell lung cancer (LSCLC). Two piloted experimental TRT regimens were of interest to study, 70 Gy daily (QD) and 61.2 Gy concomitant boost (CB). Driven by concerns about adequate patient accrual, a study design was employed that eliminated one experimental TRT arm based on early interim toxicity and tolerability, with the study then continuing as a traditional 2-arm phase III study.

METHODS: Patients with LSCLC were assigned to receive four cycles of cisplatin and etoposide chemotherapy with one of 3 TRT regimens starting with either the first or second cycle of chemotherapy. The interim endpoint was the cumulative highest toxicity calculated from a scoring system based on treatment-related grade 3 and higher toxicity and the ability to complete therapy in the experimental arms.

RESULTS: The final interim analysis was performed after 70 patients accrued to each experimental cohort, and a difference in treatment related toxicity scoring was not found (p = 0.739). Severe esophageal toxicity was comparable in both cohorts. Pulmonary toxicity was low overall, though 4 patients (5.7 %) on the 61.2 Gy arm developed grade 4 dyspnea, which was not observed in the 70 Gy arm. A protocol mandated decision was made to discontinue the 61.2 Gy arm following review of toxicity with the Data and Safety Monitoring Board.

CONCLUSION: A randomized trial design using a planned early interim toxicity analysis to discriminate between experimental treatment arms is feasible in a phase III setting. Refinement of the design could increase the likelihood of detecting clinically meaningful differences in toxicity in future studies.

PMID:33894496 | DOI:10.1016/j.lungcan.2021.04.016

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A cognitive-behavioural intervention to reduce driving anger: Evaluation based on a mixed-method approach

Accid Anal Prev. 2021 Apr 21;156:106144. doi: 10.1016/j.aap.2021.106144. Online ahead of print.

ABSTRACT

Road anger is an increasing problem that does not only lead to discomfort but is also associated with aggressive driving and an increased risk of crash involvement. Based on a cognitive-behavioural approach, we developed and tested a short group intervention (90 min) that aimed at decreasing road anger among drivers. We used a before-after control group design, surveying people who did (EG) and who did not (CG) participate in the group intervention. The sample (n = 126) consisted of 80 men and 46 women with a mean age of 54 years (SD = 13). In addition, a sub-sample (n = 37) participated in a driving simulator study before and after the intervention. To enrich the survey- and simulator-based findings, we conducted a focus group discussion about post-intervention experiences in traffic. Comparisons of pre and post survey results showed that constructive expression as measured by a slightly revised sub-scale of the Driving Anger Expression Inventory (DAX-short), increased significantly for EG participants but not within the CG. In addition, the involvement in milder forms of road anger (e.g., yelling) decreased significantly in the EG but not in the CG. In the simulator study, we observed that EG participants decreased the extent of aggressive driving, commenting and gesturing – however, none of these differences were statistically significant. EG participants self-assessed the intervention overall positive and 44 % reported that they had changed their way of thinking or reacting in traffic. Overall, results indicate a positive effect of the cognitive-behavioural group intervention. Study limitations, possibilities to improve the intervention and different areas of application are discussed.

PMID:33894475 | DOI:10.1016/j.aap.2021.106144

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Nevin Manimala Statistics

Factors impacting microbial release from environmental monitoring tools

Int J Food Microbiol. 2021 Apr 20;347:109198. doi: 10.1016/j.ijfoodmicro.2021.109198. Online ahead of print.

ABSTRACT

The U.S. FDA Food Safety Modernization Act Preventive Controls for Human Food Rule underlines the importance of an effective environmental monitoring (EM) program. EM is used to determine harborage sites of microorganisms on processing equipment, assess effectiveness of sanitation programs, and prevent transmission of foodborne pathogens. This study characterizes commercially-available polyurethane foam (PUF) and cellulose (CELL) EM tools for their efficacy in the release of foodborne pathogens from their sponge matrices. Specifically, the objectives of this study were to 1) compare the ability of EM tools to release microorganisms into a recovery eluent, 2) characterize EM tool performance at decreasing inoculum concentrations, and 3) assess the impact of various operators during the processing of EM samples. Two bacteria (Listeria monocytogenes, Salmonella Typhimurium) and one human norovirus surrogate (Tulane virus [TV]) were compared at decreasing inoculum levels utilizing two elution techniques (mechanical stomacher, manually by operator), and across six operators. Data indicated that EM tool material composition impacted the release of microorganisms (p = 0.0001), where the PUF EM tool released TV more readily than the CELL EM tool. Conversely, the decreasing inoculum levels did not statistically differ in the release of microorganisms from the EM tool matrices. In addition, no significant difference was found between the machine stomacher and manual elution by human operator or between operators. Overall, the study provides a detailed characterization of two commercially-available EM tools, and the differences identified in this study can be used to improve the effectiveness of EM programs.

PMID:33894462 | DOI:10.1016/j.ijfoodmicro.2021.109198

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Vitamin D deficiency and lung function decline in healthy individuals: A large longitudinal observation study

Respir Med. 2021 Apr 20;182:106395. doi: 10.1016/j.rmed.2021.106395. Online ahead of print.

ABSTRACT

AIM: A reliable evidence from a comprehensive large-scale study supporting associations between serum vitamin D (25-hydroxyvitamin D) level (SVDL) and lung function decline (LFD) in healthy individuals has been unavailable. Using a well-established health screening database, we assessed the associations between SVDL and LFDs, measured as the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and FEV1/FVC ratio.

METHODS: Serial SVDL and lung function data were analyzed using linear mixed models, which were performed in smokers and non-smokers, separately. Vitamin D-deficient individuals (VDDs) were defined when their SVDLs were consistently lower than 20 ng/mL at all measurements.

RESULTS: A total of 1371 individuals were analyzed. The mean FEV1 decline rates of VDDs and vitamin D-normal individuals (VDNs) in smokers were -33.35 mL/year (95% CI: 39.44 to -27.26 mL/year) and -15.61 mL/year (95% CI: 27.29 to -4.21 mL/year) respectively, over a mean of 6.29 years of observation with statistical significance (P < 0.001). However, there was no significant differences observed between decline rates of FEV1 in non-smokers. Similarly, FVC decline rates of VDDs were significantly greater than those of VDNs only in smokers (P < 0.001). However, FEV1/FVC ratio decline rates showed no significant difference between VDDs and VDNs regardless of their smoking status.

CONCLUSIONS: Consistently low SVDLs predicted more rapid FEV1 and FVC declines in smokers. However, FEV1/FVC decline rate was not associated with SVDL. SVDL may be used to identify healthy smoking individuals at high risk for accelerated LFD.

PMID:33894439 | DOI:10.1016/j.rmed.2021.106395

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Nevin Manimala Statistics

Electrochemical adsorption of perfluorooctanoic acid on a novel reduced graphene oxide aerogel loaded with Cu nanoparticles and fluorine

J Hazard Mater. 2021 Apr 12;416:125866. doi: 10.1016/j.jhazmat.2021.125866. Online ahead of print.

ABSTRACT

Perfluorooctanoic acid (PFOA) is widely concerned because its serious toxicity to the environment and ecosystems. In order to effectively and conveniently remove PFOA from aqueous solutions, reduced graphene oxide aerogel modified by Cu nanoparticles and fluorine (Cu/F-rGA) was prepared by the microbubble template method as an electrode in electrosorption. The removal capacity of Cu/F-rGA electrode to PFOA was 489% and 45.9% higher at + 0.8 V than that of open circuit and unmodified electrode, respectively. These significant improvements can be attributed to the advantages of Cu/F-rGA in ligand exchange reaction and electrostatic attraction under voltage assistance. The regeneration of Cu/F-rGA electrode maintained 75.51% capacity after 10 times electrosorption-desorption by applying reverse voltage. These properties provided potential for the reuse and application of Cu/F-rGA electrode. The electrosorption isotherm and model results showed that PFOA tended to be parallel to the adsorption site at low temperature and perpendicular at high temperature. The number of PFOA molecules connected to each adsorption site was 0.72-1.76, and the number of adsorption layers of PFOA on the electrode was between 1.46 and 2.87. Findings from this study provide a green and effective strategy to remove PFOA from aqueous solutions with low energy consumption.

PMID:33894436 | DOI:10.1016/j.jhazmat.2021.125866

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Nevin Manimala Statistics

The Role of Carotid Stenosis in a Prediction of Prognosis of Coronary Artery Disease

Pril (Makedon Akad Nauk Umet Odd Med Nauki). 2021 Apr 23;42(1):53-66. doi: 10.2478/prilozi-2021-0004.

ABSTRACT

Aims: The aim of this paper is to indicate if carotid stenosis is predictive for the prognosis of coronary artery disease.Method and materials: Our study is a prospective cohort study. 1031 patients with proven coronary artery disease (CAD) were recruited consecutively. Carotid ultrasound was used to assess IMT, plaque, or stenosis. They were followed for 24 months for adverse cardiovascular events. Selected demographic date such as smoking history, dyslipidemia, hypertension, laboratory values, and clinical data (associated diseases and risk) were collected from each patient. Total cardiovascular events and mortality rate were followed up for the study population. The results were collected prospectively and retrospectively. The study was organized as a clinical, cross-sectional study and comparative study.From the data collected with the clinical research, a file was formed in the statistical program with the help of which the data were statistically analyzed.From the methods of descriptive statistics, absolute frequencies, percentages, arithmetic mean, median, measures of variability, minimum, maximum, standard deviation and logistic regression models were used.Result: Of the total number of patients 1026 had arterial hypertension (HTA). Data on hyperlipidemia (HLP) had been reported in 895 patients. 1.023 patients had peripheral artery disease (PAB). 1031 patients were presented with multivessel coronary artery disease (CAD). There were 1,029 patients with diabetes mellitus (DM), while 1,013 patients had coronary artery by-pass (CABG), and 1,012 had stroke (CVI). Elevated systolic blood pressure was reported in 966 patients. 184 patients had elevated triglycerides and 187 had elevated cholesterol. 1,008 patients have had a history of myocardial infarction. Carotid artery stenosis (CAS) has been found in 1,009 patients, increased body mass index (BMI) in 270 patients.1.031 patients were followed for 24 months. Cardiovascular events were reported in 54 patients (or 5.2%). Revascularization was performed in 28 (4.1%) patients, while 12 (1.8%) of patients died. Diabetes mellitus (OR 1.878 95% CI 0.491 7.184) and Carotid stenosis (OR 2.185 95% CI 0.731 6.53) were found to be predictive factors for future cardiovascular events.Conclusion: Due to our results carotid ultrasound may be a useful tool for risk stratification of coronary artery disease pts.

PMID:33894121 | DOI:10.2478/prilozi-2021-0004