Tag: statistics

J Environ Manage. 2021 Aug 23;299:113550. doi: 10.1016/j.jenvman.2021.113550. Online ahead of print.

ABSTRACT

Water quality monitoring programs have been widely implemented worldwide to monitor and assess water quality and to understand its trends. However, water quality analysis based on point-source field observations is difficult to perform at large spatial and temporal scales. In this paper, a fully automated Google Earth Engine (GEE) application algorithm was developed to estimate the total suspended solids (TSS) concentration in the Chesapeake Bay based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra imagery. Combining long-term archived satellite data (2002-2020) with field observations, the concentrations and spatiotemporal patterns of TSS in the bay water were evaluated. Time series analysis showed a statistically significant decreasing trend in TSS concentration between 2002 and 2020, suggesting that the sediment concentration in the bay has gradually been decreasing over the last two decades. The decreasing trend was observed in 49 out of 60 segments of the bay, implying that substantial progress has been made toward attaining the Chesapeake Bay water quality standards. Based on the monthly TSS analysis, 12 major peak events of TSS were identified in the Chesapeake Bay, which coincided with extreme winter blizzards and summer hurricane events. The GEE application and the results presented herein complement the existing monitoring program in attaining the water quality standards of the bay.

PMID:34438312 | DOI:10.1016/j.jenvman.2021.113550

Gait Posture. 2021 Jul 24;90:106-111. doi: 10.1016/j.gaitpost.2021.07.015. Online ahead of print.

ABSTRACT

BACKGROUND: While gait termination is challenging for children with spastic cerebral palsy (CCP), few studies have quantitatively assessed this issue.

RESEARCH QUESTION: What are the characteristics of center of mass (COM) and center of pressure (COP) displacement during gait termination in CCP, and how do they compare with those in children with typical development (CTD)?

METHODS: This cross-sectional study included 13 adults with typical development (19.85 ± 0.52 years), 12 CTD (10.41 ± 2.98 years), and 16 CCP (11.15 ± 2.71 years). Participants were instructed to immediately stop walking when a stop sign appeared on a screen, which was placed at the end of an 8-m walkway. COM and COP were determined via 3-dimensional motion analysis and force plate data. Differences between the groups were assessed using the two sample t-test or Wilcoxon rank sum test. The level of statistical significance was set at P < 0.05.

RESULTS: The normalized time for stopping in CCP (4.556 ± 0.602) was higher than that in CTD (3.617 ± 0.545, P < 0.001). The normalized COP displacement (P < 0.001) and divergence between COM and COP (P < 0.001) in the mediolateral (ML) direction were significantly higher in CCP than CTD. However, the normalized divergence between COM and COP in the anteroposterior (AP) direction in CCP was lower than that in CTD (P = 0.034).

SIGNIFICANCE: The more minor divergence between COM and COP in the AP direction and the more significant COP displacement in the ML direction cause difficulty to exert braking force during gait termination. Thus, CCP require a longer time for gait termination. This finding may facilitate the development of interventions for improving gait in CCP.

PMID:34438291 | DOI:10.1016/j.gaitpost.2021.07.015

Colloids Surf B Biointerfaces. 2021 Aug 19;208:112053. doi: 10.1016/j.colsurfb.2021.112053. Online ahead of print.

ABSTRACT

Solution acidification exists under some physiological conditions (e.g. lysosomes in cells) and diseases (e.g. atherosclerosis, tumors, etc.). It is poorly understood whether and how acidification influences the size and biomechanical (stiffness and stickiness) properties of native Low-density lipoprotein (LDL) and its oxidized form (oxLDL) which plays a vital role in atherogenesis and tumorigenesis. Atomic force microscopy (AFM) evaluated that gradient acidification from pH 7.4 to pH 4.4 caused an expanding-first-and-then-shrinking decrease in size and a dramatic decrease in stiffness (but no statistically significant changes in stickiness) of LDL/oxLDL particles by influencing secondary/tertiary structures and lipid release detected by infrared spectral analysis and cholesterol detection, respectively. The smaller and softer characteristics of LDL/oxLDL at acidic conditions versus at the neutral pH partially explains the atherogenic role of acidification. The data may provide important information for a better understanding of LDL/oxLDL and some diseases (e.g. atherosclerosis and tumors).

PMID:34438294 | DOI:10.1016/j.colsurfb.2021.112053

ESMO Open. 2021 Aug 23;6(5):100236. doi: 10.1016/j.esmoop.2021.100236. Online ahead of print.

ABSTRACT

BACKGROUND: In this study, we evaluated the association between genetic polymorphisms of 23 genes associated with gemcitabine metabolism and the clinical efficacy of gemcitabine in breast cancer patients.

PATIENTS AND METHODS: This prospective, pharmacogenetic study was conducted in cooperation with a phase II clinical trial. A total of 103 genetic polymorphisms of the 23 genes involved in gemcitabine transport and metabolism were selected for genotyping. The associations of genetic polymorphisms with overall survival, progression-free survival (PFS), and 6-month PFS were analyzed.

RESULTS: A total of 91 breast cancer patients were enrolled in this study. In terms of 6-month PFS, rs1044457 in CMPK1 was the most significant genetic polymorphism [55.9% for CT and TT and 78.9% for CC, P < 0.001, hazard ratio (HR): 4.444, 95% confidence interval (CI): 1.905-10.363]. For the rs693955 in SLC29A1, the median duration of PFS was 5.4 months for AA and 10.5 months for CA and CC (P = 0.002, HR: 3.704, 95% CI: 1.615-8.497). For the rs2807312 in TLE4, the median duration of PFS was 5.7 months for TT and 10.4 months for CT and CC (P = 0.005, HR: 4.948, 95% CI: 1.612-15.190). In survival analysis with a multi-gene model, the TT genotype of rs2807312 had the worst PFS regardless of other genetic polymorphisms, whereas the CA genotype of rs693955 or the CT genotype of rs2807312 without the AA genotype of rs693955 had the best PFS compared with those of other genetic groups (P < 0.001).

CONCLUSIONS: Genetic polymorphisms of rs1044457 in CMPK1, rs693955 in SLC29A1, and rs2807312 in TLE4 were significantly associated with the 6-month PFS rate and/or the duration of PFS. Further studies with a larger sample size and expression study would be helpful to validate the association of genetic polymorphisms and clinical efficacy of gemcitabine.

PMID:34438242 | DOI:10.1016/j.esmoop.2021.100236

Oral Oncol. 2021 Aug 23;121:105501. doi: 10.1016/j.oraloncology.2021.105501. Online ahead of print.

ABSTRACT

OBJECTIVES: Adenoid cystic carcinoma (ACC) is the malignancy most likely to spread perineurally. Delayed diagnosis often leads to undetected perineural spread (PNS). Better understanding of diagnostic processes, clinical and imaging features in ACC may allow earlier diagnoses.

MATERIALS AND METHODS: A retrospective records search of the University of Washington Radiology archive identified patients with palatal ACC diagnosis and pre-treatment MDCT and/or MRI. Demographic data, clinical findings, diagnostic workup history and image features including the presence of PNS were recorded.

RESULTS: 44 patients met inclusion and exclusion criteria. Symptoms included pain, mass, numbness, and sinonasal congestion. The most common finding on clinical examination was visible or palpable palatal mass. 55% of patients were evaluated by a dentist pre-diagnosis. Most common initial impressions were infection and/or dental disease. PNS was identified in 81.8% of patients, most commonly at pterygopalatine fossa, palatine foramina/canals, Vidian canal, or foramen rotundum. PNS was statistically significantly associated with paresthesia (p = 0.003) but not with tumor size, age, gender, or tobacco history. 44% of patients were diagnosed ≥1 year from initial symptoms, with a mean delay of 18.3 (range < 1-72) months.

CONCLUSIONS: This study represents the first analysis of the nature of the diagnostic process of palatal ACC. Majorities of patients were evaluated by a general dentist pre-diagnosis. PNS was identified in a majority of patients and all the patients who presented with paresthesia had evidence of PNS. Despite patients presenting with paresthesia, palatal ACC is often initially misdiagnosed resulting in delayed diagnosis.

PMID:34438281 | DOI:10.1016/j.oraloncology.2021.105501

Bioresour Technol. 2021 Aug 17;341:125764. doi: 10.1016/j.biortech.2021.125764. Online ahead of print.

ABSTRACT

Microbial fermentation plays important roles in hydrogen production. Various methods to promote hydrogen production are being developed. Here, different magnetic field intensities (2.7 mT, 3.2 mT and 9.1 mT) were applied to the glucose fermentation system of Clostridium pasteurianum to evaluate the feasibility and effect of statistic magnetic field on hydrogen production. The results showed that the magnetic field intensity of 3.2 mT effectively enhanced the hydrogen production. The total glucose consumption reached 0.64 ± 0.010 mmol, the maximum hydrogen yield reached 2.34 ± 0.020 mol H₂/mol glucose, and the maximum hydrogen production rate reached 0.065 ± 0.002 mmol/h. Compared with the control, the maximum biomass, carbon conversion efficiency and energy conversion efficiency were elevated by 366%, 114%, and 26.8%, respectively. Our results provide a new way for promotion of hydrogen production, better understanding of the interaction mechanism between magnetic field and microorganisms and for optimizing the hydrogen production.

PMID:34438289 | DOI:10.1016/j.biortech.2021.125764

J Forensic Leg Med. 2021 Aug 20;83:102242. doi: 10.1016/j.jflm.2021.102242. Online ahead of print.

ABSTRACT

A prospective study was undertaken of 150 medicolegal cases where five or more tattoos were identified in anatomically separate areas. All cases were the subject of full police and coronial investigations with examination by forensic pathologists. There were 120 males and 30 females (M:F = 4:1) with an age range of 22-86 years (mean = 48.1 years). 78 cases were found where deaths were due to natural diseases (52%) (age range 27-82 years; mean 55.3 years; M:F = 4.2:1). 72 cases (48%) were found where deaths were classified as unnatural – 23 drug/alcohol related, 37 suicides, 12 accidents and 0 homicides (age range 20-66 years; mean 39.8 years; M:F = 3.8:1). This distribution was not shown to be statistically different to a control group of 100 non-tattooed individuals where there were 56 natural and 44 unnatural deaths (p = 0.3). Thus, although certain types of tattoos may be associated with an increased number of unnatural deaths in a medicolegal environment, the actual number of tattoos appears to have minimal effect.

PMID:34438228 | DOI:10.1016/j.jflm.2021.102242

Int J Pediatr Otorhinolaryngol. 2021 Aug 20;150:110893. doi: 10.1016/j.ijporl.2021.110893. Online ahead of print.

ABSTRACT

BACKGROUND: Neck-related chief complaints are common in the pediatric Emergency Department (ED), and although the incidence of pathology such as retropharyngeal abscesses is rare, the ability to rule out abscesses requiring surgical/procedural intervention is essential. However, there are no clear clinical guidelines regarding work-up and diagnosis in this population, possibly contributing to an excess use of potentially harmful and costly computed tomography (CT) imaging.

OBJECTIVE: In this study we sought to identify historical, physical exam, and laboratory findings associated with surgically significant neck abscesses to better delineate CT neck imaging criteria.

METHODS: We conducted a retrospective chart review of all patients ≤18 years presenting to a pediatric ED between 2013 and 2017 who underwent CT neck imaging. Surgically significant abscesses (SSAs) were defined as abscesses ≥2 cm, retropharyngeal abscesses (RPA), parapharyngeal abscesses (PPA), or peritonsillar abscesses (PTA). Historical factors, physical exam findings, laboratory results, demographics, and CT results were analyzed using univariate statistical analysis and regression models.

RESULTS: A total of 718 patients received neck CTs and 153 SSAs were identified. In children younger than 6 years, factors associated with statistically significant increased odds of an SSA were reported throat pain (OR 1.18; 95% CI 1.05, 1.33), fussiness (OR 1.18; 1.01, 1.39), lethargy (OR 1.43; 1.07, 1.91), tonsillar enlargement (OR 1.17; 1.02, 1.34), C-reactive protein (CRP) > 10 (OR 1.22; 1.07, 1.40), and an ED visit within the preceding week (OR 1.18; 1.04, 1.33). In children older than 6 years, the factors associated with statistically significant increased odds of an SSA included current antibiotic use (OR 1.12; 1.02, 1.22) and a CRP >10 (OR 1.14; 1.03, 1.26).

CONCLUSION: Some historical, physical exam, and laboratory findings are associated with SSAs, and while not definitive in isolation, may be beneficial additions to routine SSA assessment, as a supplement to clinical judgement regarding CT and observation decisions. This may potentially allow for the identification of patients requiring CT versus those who may not, and thus the opportunity to safely reduce the use of CT imaging in select patients.

PMID:34438187 | DOI:10.1016/j.ijporl.2021.110893

Mult Scler Relat Disord. 2021 Aug 14;55:103205. doi: 10.1016/j.msard.2021.103205. Online ahead of print.

ABSTRACT

BACKGROUND: People with Multiple Sclerosis (PwMS) experience a wide range of symptoms that can alter function and limit activity and community participation. Symptoms including sensory changes, weakness, fatigue and others have been well documented. However, symptoms related to changes in vestibular related function, including gaze and postural stability have not been fully explored. While some recent studies have begun to provide insight into these deficits in PwMS and have explored the use of rehabilitation paradigms for their management, much remains unknown about the full extent of these deficits. Therefore, this study aimed to characterize the presence of gaze and postural stability deficits in measures across the World Health Organization International Classification of Functioning, Disability, and Health (WHO ICF) and to examine how deficits in domains of body structure and function and activity contribute to participation level limitations.

METHODS: Baseline data from 41 PwMS (mean(SD) age = 53.9(11.2), 78% female) enrolled as part of a randomized clinical trial were used in this analysis. Measures of gaze and postural stability from the ICF domains of body structure and function (Vestibular ocular reflex [VOR] gain and postural sway area), activity (computerized dynamic visual acuity [cDVA] and MiniBEST test), and participation (Dizziness handicap inventory [DHI] and Activities Balance Confidence [ABC] scale) along with demographic data were used to characterize the sample. To explore relationships between ICF domains for gaze and postural stability, univariate correlations were performed between measures from each domain using Pearson’s correlations. Separate multivariate regression models examined how measures from the body structure and function and activity domains contributed to the variance in the participation level outcomes. Variance explained by the models was quantified using R-squared statistic and contribution of the independent variables were quantified using the beta coefficient (p < 0.05).

RESULTS: Correlation analysis demonstrated significant relationships in the postural stability measures across domains. Specifically, between postural sway area on a firm surface and MiniBEST test score (r = -.48;p < 0.01) and MiniBEST test score and ABC score (r = 0.5;p < 0.01). Significant correlations were also found between the gaze stability measures of horizontal and vertical VOR gain (r = .68;p < 0.001), horizontal VOR gain and dynamic visual acuity (r = .38;p = 0.02), and vertical VOR gain and dynamic visual acuity (r = .54;p < 0.001). Regression models assessing postural stability, found that only the MiniBEST score significantly contributed to the variance in ABC score (p = 0.01) and the full model explained 34% of the variance in ABC score. Regression modeling of gaze stability outcomes did not produce any variable that significantly contributed to the variance in DHI score and the full model explained 18% of the variance in DHI score.

CONCLUSIONS: PwMS in this sample demonstrated deficits in gaze and postural stability across the domains of the WHO ICF compared to past samples of PwMS and healthy cohorts. Correlation between measures in the different domains were present, but no strong relationship between measures of body structure and function, activity and participation level outcomes were observed. This lack of relationship across the domains is likely contributed to the relatively small sample size, the high level of variability observed in the outcomes, and the diverse presentation often seen in PwMS.

PMID:34438218 | DOI:10.1016/j.msard.2021.103205

J Forensic Leg Med. 2021 Aug 21;83:102244. doi: 10.1016/j.jflm.2021.102244. Online ahead of print.

ABSTRACT

BACKGROUND: Three-dimensional imaging is a rapidly growing technology that has revealed exciting insights in disparate fields of research, especially in medicine, forensics, and archaeology. Recent advancements in this technology have also made a remarkable impact in the field of anthropology and odontology. A major benefit of this technology is that they offer effective methods of creating digital records that can aid in physical documentation and can be digitally stored for later assessment and research.

AIM: The aim of the current study is to evaluate the metric accuracy of 3D models generated using three different 3D acquisition techniques for performing metric analytical procedures.

MATERIALS AND METHOD: Twenty standard craniometric linear measurements (using both sliding and spreading callipers) were taken on two craniums and eight standard measurements were taken on 2 mandibles (using sliding callipers and a mandibulometer); these measurements were then replicated on 3D digital models.

RESULTS: Statistical analysis of these dataset using Analysis of Variance (ANOVA) and post hoc Bonferroni test suggested that the physical and virtual measurements were accurate, comparable, and concordant (p > 0.05).

CONCLUSION: These findings open up numerous avenues for future study, especially in the fields of forensics and clinical studies. However, in order to overcome the limitations faced in using the digital method certain standardised protocols and guidelines must be established to record these data.

PMID:34438227 | DOI:10.1016/j.jflm.2021.102244