An innovative statistical approach for analysing non-continuous variables in environmental monitoring: assessing temporal trends of TBT pollution

2011 ◽  
Vol 13 (3) ◽  
pp. 673 ◽  
Author(s):  
José António Santos ◽  
Susana Galante-Oliveira ◽  
Carlos Barroso
Keyword(s):  
Environmental Monitoring ◽  
Statistical Approach ◽  
Temporal Trends ◽  
Continuous Variables ◽  
Tbt Pollution

scholarly journals Getis-Ord Gi* statistics for hydrocarbons content analysis in the Tromjegan river basin

2020 ◽  
Vol 26 (2) ◽  
pp. 151-160
Author(s):  
Valentina Dobryakova ◽  
Natalya Moskvina ◽  
Andrey Dobryakov ◽  
Lilia Zhegalina ◽  
Ildar Idrisov
Keyword(s):  
Environmental Monitoring ◽  
River Basin ◽  
Surface Waters ◽  
Temporal Dynamics ◽  
Hot Spot ◽  
Temporal Trends ◽  
Environmental Research ◽  
Analysis Tool ◽  
Hydrocarbon Pollution ◽  
Average Maximum

The information content and effectiveness of ecological research of the territory can be improved using the methods of multivariate analysis and mapping of the results. The article presents the analysis and mapping results of spatial and temporal trends of hydrocarbon pollution in the Tromjegan river basin for the period 2006–2018 using the tools of ArcGIS Pro. The informational and basic research is the data of local environmental monitoring of licensed blocks of the Khanty-Mansiysk Autonomous Okrug — Ugra. Pollution analysis was carried out on the basis of a detailed study of the geography of the source data using statistical calculations (minimum, average, maximum distances between sampling points, Getis-Ord Gi* index). Thematic maps were constructed using data averaged over the year. The spatial and temporal dynamics of hydrocarbons concentration in surface waters for 2006–2018 is analyzed using the “Hot Spot Analysis” tool. A temporary cluster section of hydrocarbons average annual concentration according to the Getis-Ord Gi* indicator allowed us to identify trends in the dynamics of indicators. Maps of hydrocarbons average annual concentration were compiled and the results of a spatial-temporal analysis of hydrocarbons average annual concentration in surface waters were presented. The identification of patterns in large arrays of long-term data and the consideration of the spatial component are necessary elements of modern environmental research. Analysis of the time series of average annual concentrations in the Tromjegan river basin showed a clear trend in the dynamics of hydrocarbon pollution. The findings can be the basis for making managerial decisions in the environmental monitoring of licensed blocks of the Khanty-Mansiysk Autonomous Okrug — Ugra.

Trends in Medial Ulnar Collateral Ligament Repair and Reconstruction From 2007 to 2016: A Population-Based Study of a Large Private Insurance Database

2021 ◽  
pp. 155633162199781
Author(s):  
Jacqueline E. Baron ◽  
Robert W. Westermann ◽  
David E. DeMik ◽  
Qiang An ◽  
Brian R. Wolf
Keyword(s):  
Incidence Rate ◽  
Private Insurance ◽  
Temporal Trends ◽  
Ulnar Collateral Ligament ◽  
Incidence Rates ◽  
Return To Play ◽  
Categorical Variables ◽  
Administrative Claims ◽  
Continuous Variables ◽  
Collateral Ligament

Background: Ulnar collateral ligament (UCL) reconstruction and UCL repair of the elbow are commonly performed procedures, resulting in high return-to-play rates. Whether the incidence rate of UCL reconstruction vs UCL repair has changed over time is not currently known. Purpose/Questions: We sought to assess temporal trends in the incidence rates of UCL repair and UCL reconstruction and to identify factors associated with UCL reconstruction. We hypothesized that UCL repair would demonstrate an increased incidence overall in recent years with an associated decline in UCL reconstruction rates. Methods: Using the PearlDiver Research Program to query the Humana administrative claims database, we identified patients who had undergone UCL repair and/or reconstruction from 2007 to 2016. Patients were stratified by age (15–19; 20–29; 30–49 years), sex, and year (2007–2011 vs 2012–2016). Poisson regression analysis (continuous variables) was used to calculate the incidence risk ratio (IRR); chi-square tests were performed for categorical variables, and odds ratios were calculated with 95% confidence intervals (CI). Results: The incidence rate of UCL repair was greater in 2012–2016 than in 2007–2011 (IRR: 1.86, 95% CI: 1.16–2.96). The incidence rate of UCL reconstruction vs UCL repair was greater for patients aged 15 to 19 years (IRR: 3.37, 95% CI: 1.97–5.77) but not patients aged 20 to 29 years (IRR: 0.89, 95% CI: 0.49–1.59) as compared with patients aged 30 to 49. Males aged 19 years were more likely than females to undergo UCL reconstruction (IRR: 10.09, 95% CI: 1.37–3.45). Conclusion: While UCL procedures are becoming more popular, our retrospective analysis showed that young males are preferentially treated with UCL reconstruction, warranting further investigation into these trends.

Assessment of temporal genetic variability of two epibenthic amphipod species in an eastern Australian estuarine environment and their suitability as biological monitors

2014 ◽  
Vol 62 (3) ◽  
pp. 206
Author(s):  
Pann Pann Chung ◽  
Ida Chu ◽  
J. William O. Ballard
Keyword(s):  
Genetic Variation ◽  
Genetic Variability ◽  
Environmental Monitoring ◽  
Organic Contaminants ◽  
Population Studies ◽  
Temporal Trends ◽  
Natural Populations ◽  
Cytochromec Oxidase ◽  
Basic Research ◽  
Amphipod Species

Population studies often assume temporally stable and consistent patterns of genetic variability. Violations of this assumption can lead to misrepresentation of the amount and patterns of genetic variability in natural populations, which can be problematic in basic research and environmental monitoring studies that are designed to detect environmental perturbation. We collected two endemic species of amphipods, Melita plumulosa and Melita matilda, in a major eastern Australian waterway between November 2009 and October 2011, and assessed genetic variation at the mitochondrial cytochromec oxidase subunitI locus. Overall, M. plumulosa was found to be more genetically variable than M. matilda. No distinct temporal trends in levels and patterns of genetic variation were identified in either species. These findings, combined with the published results demonstrating that M. plumulosa has greater sensitivity to a range of sediment-bound metals and organic contaminants, suggests it to be an informative species for environmental monitoring purposes.

scholarly journals Analysis of the Space–Temporal Trends of Wet Conditions in the Different Rainy Seasons of Brazilian Northeast by Quantile Regression and Bootstrap Test

Geosciences ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 457 ◽  
Author(s):  
Rodrigo Lins da Rocha Júnior ◽  
Fabrício Daniel dos Santos Silva ◽  
Rafaela Lisboa Costa ◽  
Heliofábio Barros Gomes ◽  
Dirceu Luis Herdies ◽  
...  
Keyword(s):  
Quantile Regression ◽  
Statistical Approach ◽  
Potential Evapotranspiration ◽  
Interpolation Method ◽  
Statistical Significance ◽  
Temporal Trends ◽  
Extreme Rainfall ◽  
Bootstrap Test ◽  
June July ◽  
Brazilian Northeast

Drought causes serious social and environmental problems that have great impact on the lives of thousands of people all around the world. The purpose of this research was to investigate the trends in humid conditions in the northeast of Brazil (NEB) in the highest climatic precipitation quarters, November–December–January (NDJ), February–March–April (FMA), and May–June–July (MJJ), through the standardized precipitation and evapotranspiration index (SPEI), considering an alternative statistical approach. Precipitation and potential evapotranspiration (PET) time series for the calculation of the SPEI were extracted for the 1794 NEB municipalities between 1980 and 2015 from a grid dataset with a resolution of 0.25° × 0.25° using the bilinear interpolation method. The trends and statistical significance of the SPEI were estimated by quantile regression (QR) and the bootstrap test. In NDJ, opposite trends were seen in the eastern NEB (~0.5 SPEI/decade) and in the south (~−0.6 SPEI/decade). In FMA, most of NEB presented negative trends in the 0.50 and 0.95 quantiles (~−0.3 SPEI/decade), while in MJJ, most of NEB presented positive trends in all quantiles studied (~0.4 SPEI/decade). The results are consistent with observational analyses of extreme rainfall.

Twitter Usage Using Common Reference to Tinnitus

2020 ◽  
Vol 29 (2) ◽  
pp. 206-217
Author(s):  
Jianyuan Ni ◽  
Monica L. Bellon-Harn ◽  
Jiang Zhang ◽  
Yueqing Li ◽  
Vinaya Manchaiah
Keyword(s):  
Nonprofit Organizations ◽  
Temporal Trends ◽  
Temporal Analysis ◽  
Cross Sectional ◽  
For Profit ◽  
Common Reference ◽  
Personal Experiences ◽  
Twitter Users ◽  
Sectional Analysis ◽  
Share Information

Objective The objective of the study was to examine specific patterns of Twitter usage using common reference to tinnitus. Method The study used cross-sectional analysis of data generated from Twitter data. Twitter content, language, reach, users, accounts, temporal trends, and social networks were examined. Results Around 70,000 tweets were identified and analyzed from May to October 2018. Of the 100 most active Twitter accounts, organizations owned 52%, individuals owned 44%, and 4% of the accounts were unknown. Commercial/for-profit and nonprofit organizations were the most common organization account owners (i.e., 26% and 16%, respectively). Seven unique tweets were identified with a reach of over 400 Twitter users. The greatest reach exceeded 2,000 users. Temporal analysis identified retweet outliers (> 200 retweets per hour) that corresponded to a widely publicized event involving the response of a Twitter user to another user's joke. Content analysis indicated that Twitter is a platform that primarily functions to advocate, share personal experiences, or share information about management of tinnitus rather than to provide social support and build relationships. Conclusions Twitter accounts owned by organizations outnumbered individual accounts, and commercial/for-profit user accounts were the most frequently active organization account type. Analyses of social media use can be helpful in discovering issues of interest to the tinnitus community as well as determining which users and organizations are dominating social network conversations.

Modelling In-Patient Bed Usage Behaviour in a Department of Geriatric Medicine

1993 ◽  
Vol 32 (01) ◽  
pp. 79-81 ◽  
Author(s):  
P. Millard ◽  
S. McClean
Keyword(s):  
Census Data ◽  
Geriatric Medicine ◽  
Temporal Trends ◽  
Exponential Model ◽  
Bed Occupancy ◽  
Lengths Of Stay ◽  
Geriatric Hospital ◽  
Using Data ◽  
Acute Patients

Abstract:The flow of patients through geriatric hospitals has been previously described in terms of acute and long-stay states where the bed occupancy at a census point is modelled by a mixed exponential model. Using data for sixteen years the model was fitted to successive annual census points, in order to provide a description of temporal trends. While the number of acute patients has remained fairly stable during the period, the model shows that there has been a decrease in the number of long-stay patients. Mean lengths of stay in our geriatric hospital before death or discharge have decreased during the study period for both acute and long-stay patients.Using these fits of the mixed exponential model to census data, a method is provided for predicting future turnover of patients. These predictions are reasonably good, except when the turnover patterns go through a period of flux in which assumption of stability no longer holds. Overall, a methodology is presented which relates census analysis to the behaviour of admission cohorts, thus producing a means of predicting future behaviour of patients and identifying where there is a change in patterns.

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