scholarly journals Hydrodynamic and probabilistic modelling of storm overflow discharges

2018 ◽  
Vol 20 (5) ◽  
pp. 1100-1110 ◽  
Author(s):  
Szeląg Bartosz ◽  
Adam Kiczko ◽  
Jan Studziński ◽  
Lidia Dąbek
Keyword(s):  
Logistic Regression ◽  
Confidence Intervals ◽  
Hydrodynamic Model ◽  
Probabilistic Model ◽  
Numerical Experiments ◽  
Precipitation Event ◽  
Annual Number ◽  
Probabilistic Modelling ◽  
Probabilistic Description ◽  
Calculated Number

Abstract The study compares an annual number of weir overflows calculated using a hydrodynamic model by continuous simulations and a probabilistic model. The weir outflow for a single precipitation event was successfully modelled using logistic regression. Performed numerical experiments showed that the calculated number of weir outflows with the hydrodynamic model falls within confidence intervals of the probabilistic model. This suggests that the model of the logistic regression can be used in practice. The probabilistic simulations revealed that a model with a probabilistic description of a number of annual precipitations and a model with an assumed average number of such events are not consistent. The proposed methodology can be applied for the design of outflow weirs and other storm devices.

scholarly journals Attitudes towards the New Zealand Government’s Smokefree 2025 goal associated with smoking and vaping in university students aged 18 to 24 years: results of a 2018 national cross-sectional survey

BMJ Open ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. e037362
Author(s):  
Ben Wamamili ◽  
Mark Wallace-Bell ◽  
Ann Richardson ◽  
Randolph C Grace ◽  
Pat Coope
Keyword(s):  
Logistic Regression ◽  
Regression Analysis ◽  
New Zealand ◽  
University Students ◽  
Confidence Intervals ◽  
Logistic Regression Analysis ◽  
Smoking Prevalence ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Lower Odds

ObjectiveIn March 2011, New Zealand (NZ) launched an aspirational goal to reduce smoking prevalence to 5% or less by 2025 (Smokefree 2025 goal). Little is known about university students’ awareness of, support for and perceptions about this goal. We sought to narrow the knowledge gap.SettingUniversity students in NZ.MethodsWe analysed data from a 2018 cross-sectional survey of university students across NZ. Logistic regression analysis examined the associations between responses about the Smokefree goal with smoking and vaping, while controlling for age, sex and ethnicity. Confidence intervals (95% CI) were reported where appropriate.ParticipantsThe sample comprised 1476 students: 919 (62.3%) aged 18 to 20 and 557 (37.7%) aged 21 to 24 years; 569 (38.6%) male and 907 (61.4%) female; 117 (7.9%) Māori and 1359 (92.1%) non-Māori. Of these, 10.5% currently smoked (ie, smoked at least monthly) and 6.1% currently vaped (ie, used an e-cigarette or vaped at least once a month).ResultsOverall awareness of the Smokefree goal was 47.5% (95% CI: 44.9 to 50.1); support 96.9% (95% CI: 95.8 to 97.8); belief that it can be achieved 88.8% (95% CI: 86.8 to 90.7) and belief that e-cigarettes/vaping can help achieve it 88.1% (95% CI: 86.0 to 89.9).Dual users of tobacco cigarettes and e-cigarettes had greater odds of being aware of the Smokefree goal (OR=3.07, 95% CI: 1.19 to 7.92), current smokers had lower odds of supporting it (OR=0.13, 95% CI: 0.06 to 0.27) and of believing that it can be achieved (OR=0.15, 95% CI: 0.09 to 0.24) and current vapers had greater odds of believing that e-cigarettes/vaping can help to achieve it (OR=8.57, 95% CI: 1.18 to 62.52) compared with non-users.ConclusionsThe results suggest strong overall support for the Smokefree goal and belief that it can be achieved and that e-cigarettes/vaping can help achieve it. Smoking and vaping were associated with high awareness of the Smokefree goal, but lower support and optimism that it can be achieved.

scholarly journals Does Schoolmate and Teacher Support Buffer against the Effect of Adverse Childhood Experiences on Emotional and Behavioural Problems?

2021 ◽  
Vol 18 (24) ◽  
pp. 13009
Author(s):  
Miriama Lackova Rebicova ◽  
Zuzana Dankulincova Veselska ◽  
Daniela Husarova ◽  
Andrea Madarasova Geckova ◽  
Danielle E. M. C. Jansen ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Confidence Intervals ◽  
Health Behaviour ◽  
Adverse Childhood Experiences ◽  
Teacher Support ◽  
Behavioural Problems ◽  
Emotional And Behavioural Problems ◽  
Childhood Experiences ◽  
School Aged Children ◽  
Adverse Childhood

This study aims to explore the associations of schoolmate and teacher support with emotional and behavioural problems (EBP) and whether schoolmate and teacher support affects the associations of adverse childhood experiences (ACE) and of EBP in adolescence. We obtained data from 5220 students aged from 11 to 15 (48.7% boys), who participated in the Health Behaviour in a School-aged Children study (2018, Slovakia). Using logistic regression adjusted for gender, age and family affluence we assessed the modification of the relations of ACE and EBP by schoolmate and teacher support. Schoolmate and teacher support decreased the probability of EBP (Odds Ratios, 95% confidence intervals: 0.76, 0.74|0.79; and 0.86, 0.83|0.89, respectively). However, we found no statistically significant interactions of schoolmate and teacher support regarding the association of ACE with EBP. Schoolmate and teacher support decreased the likelihood of EBP among adolescents but do not buffer the relation of any previous ACE with EBP.

scholarly journals Analysis of the Relationship between Asthma and Coffee/Green Tea/Soda Intake

2020 ◽  
Vol 17 (20) ◽  
pp. 7471
Author(s):  
Jee Hye Wee ◽  
Dae Myoung Yoo ◽  
Soo Hwan Byun ◽  
Chang Myeon Song ◽  
Hyo-Jeong Lee ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Confidence Intervals ◽  
Green Tea ◽  
Coffee Consumption ◽  
Protective Effects ◽  
Multiple Logistic Regression ◽  
Regression Analyses ◽  
Epidemiology Study ◽  
Soda Consumption ◽  
The Relationship

This study aimed to evaluate the association between asthma and the intake of coffee/green tea/soda. We used Health Examinee data from the Korean Genome and Epidemiology Study (2004–2016). The participants (n = 3146 with asthma; n = 158,902 non-asthma) were asked about the frequency and amount of their coffee/green tea/soda intake. Multiple logistic regression analyses were used to calculate the adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for asthma according to the frequency and amount of coffee/green tea/soda intake. Compared to the group consuming no coffee, the aORs for asthma were 0.82 (95% CI = 0.73–0.93, p = 0.002) in the group consuming coffee 1–2 times/day and 0.87 (95% CI = 0.78–0.97, p = 0.011) in the group consuming coffee in quantities of 1 cup, respectively. However, the frequency and amount of green tea and soda consumption were not significantly associated with asthma after adjusting for coffee consumption (all p > 0.05). These findings were consistent in the female subgroup (1–2 times/day: aOR = 0.76, 95% CI = 0.66–0.87, p < 0.001, and 1 cup each time: aOR = 0.79, 95% CI = 0.70–0.90, p < 0.001) but not in the male subgroup. Drinking 1 cup of coffee each time and 1–2 times per day may have protective effects against asthma in a Korean population. However, the associations between asthma and green tea/soda cannot be clearly established.

Anemia and HIV in the Antiretroviral Era: Potential Significance of Testosterone.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3722-3722
Author(s):  
Caroline M. Behler ◽  
Starley B. Shade ◽  
Kellan Gregory ◽  
Donald I. Abrams ◽  
Paul A. Volberding
Keyword(s):  
Logistic Regression ◽  
Antiretroviral Therapy ◽  
Confidence Intervals ◽  
Opportunistic Infections ◽  
P Value ◽  
Hiv Disease ◽  
Odds Ratios ◽  
Multivariable Logistic Regression Model ◽  
Testosterone Levels ◽  
Low Testosterone

Abstract BACKGROUND: Anemia remains the most common hematologic disorder in human immunodeficiency virus (HIV) infection despite the use of effective antiretroviral therapy, and is associated with decreased quality of life and survival. Hypogonadism is prevalent in advanced HIV disease, however low testosterone levels have not been customarily implicated in HIV-associated anemia. This study was undertaken to determine whether there is a relationship between testosterone levels and androgen use with anemia in HIV, and to characterize other clinical correlates of HIV-associated anemia. METHODS: This cross-sectional study examined the clinical characteristics of 200 HIV positive patients at a public hospital HIV clinic and clinical features associated with anemia. A written questionnaire detailed previous and current medication use, opportunistic infections and malignancies. Hematologic and virologic parameters, testosterone and erythropoietin levels were measured; CD4 count and viral load nadir and peak levels were obtained from the computerized medical record. Anemia was defined as hemoglobin <13.5 g/dL in men and <11.6 g/dL in women. RESULTS: Anemia was present in 24% of women and 28% of men. Anemia was negatively associated with female sex (adjusted OR 0.30, 95% CI 0.11–0.85), current antiretroviral therapy (adjusted OR 0.43, 95% CI 0.20–0.95), current androgen use (adjusted OR 0.20, 95% CI 0.05–0.84) and macrocytosis (adjusted OR 0.23, 95% CI 0.09–0.61). Anemia was positively associated with lymphopenia (adjusted OR 4.0, 95% CI 1.36–11.80), high erythropoieitin levels (adjusted OR 7.73, 95% CI 2.92–20.48) and low testosterone levels (adjusted OR 3.27, 95% CI 1.01–10.60). CONCLUSIONS: Low testosterone levels may have a positive association, and supplemental androgens a negative association with anemia in HIV disease. Predictors of Anemia Unadjusted odds ratios and 95% confidence intervals obtained by logistic regression. Variables that achieved a p-value of <0.1 in tests of interaction were included in a multivariable logistic regression model, which was used to obtain adjusted odds ratios and 95% confidence intervals. N % Anemic Unadjusted OR (95% CI) Adjusted OR (95% CI) Female 38 23.7 0.78 (0.34, 1.78) 0.30 (0.11, 0.85) Male/MTF Transgender 162 28.4 Lymphopenia (<1.0x109/L) 19 57.9 3.05 (1.24, 7.51) 4.00 (1.36, 11.80) Normal Lymphocyte Count 178 24.7 Macrocytosis (MCV>100fL) 71 14.1 0.34 (0.16, 0.74) 0.23 (0.09, 0.61) Normal MCV 117 32.5 Microcytosis (MCV<80fL) 11 63.6 2.91 (0.87, 9.77) 2.02 (0.50, 8.13) Current Antiretroviral Therapy 139 20.1 0.32 (0.17, 0.61) 0.43 (0.20, 0.95) No current Antiretroviral Therapy 61 44.3 Current Androgen Use 23 13.0 0.36 (0.10, 1.27) 0.20 (0.05, 0.84) No Current Androgen Use 171 28.7 EPO x Testosterone Interaction High EPO-High/nl Testosterone 46 41.3 2.50 (1.23, 5.11) 7.73 (2.92, 20.48) Low/nl EPO-Low Testosterone 24 37.5 2.39 (0.89, 6.39) 3.27 (1.01, 10.60) High EPO-Low Testosterone 11 27.3 0.33 (0.04, 2.50) 0.17 (0.012, 2.36) Low/nl EPO-High/nl Testosterone 115 20.9

Reliability of Pharmacodynamic Analysis by Logistic Regression

2000 ◽  
Vol 92 (4) ◽  
pp. 985-992 ◽  
Author(s):  
Wei Lu ◽  
James M. Bailey
Keyword(s):  
Logistic Regression ◽  
Confidence Intervals ◽  
Coefficient Of Variation ◽  
Parameter Estimates ◽  
True Parameter ◽  
True Value ◽  
Coefficients Of Variation ◽  
Effect Relation ◽  
Log Normal ◽  
Multiple Patients

Background Many pharmacologic studies record data as binary yes-or-no variables, and analysis is performed using logistic regression. This study investigates the accuracy of estimation of the drug concentration associated with a 50% probability of drug effect (C50) and the term describing the steepness of the concentration-effect relation (gamma). Methods The authors developed a technique for simulating pharmacodynamic studies with binary yes-or-no responses. Simulations were conducted assuming either that each data point was derived from the same patient or that data were pooled from multiple patients in a population with log-normal distributions of C50 and gamma. Coefficients of variation were calculated. The authors also determined the percentage of simulations in which the 95% confidence intervals contained the true parameter value. Results The coefficient of variation of parameter estimates decreased with increasing n and gamma. The 95% confidence intervals for C50 estimation contained the true parameter value in more than 90% of the simulations. However, the 95% confidence intervals of gamma did not contain the true value in a substantial number of simulations of data from multiple patients. Conclusion The coefficient of variation of parameter estimates may be as large as 40-50% for small studies (n &lt; or = 20). The 95% confidence intervals of C50 almost always contain the true value, underscoring the need for always reporting confidence intervals. However, when data from multiple patients is naively pooled, the estimates of gamma may be biased, and the 95% confidence intervals may not contain the true value.

Numerical Modeling of Bioluminescence Distributions in the Coastal Ocean*

2003 ◽  
Vol 20 (7) ◽  
pp. 1060-1068 ◽  
Author(s):  
Igor Shulman ◽  
Steven H. D. Haddock ◽  
Dennis J. McGillicuddy ◽  
Jeffrey D. Paduan ◽  
W. Paul Bissett
Keyword(s):  
Hydrodynamic Model ◽  
Numerical Experiments ◽  
Flow Direction ◽  
Circulation Model ◽  
Velocity Fields ◽  
Monterey Bay ◽  
Resolution Model ◽  
Tracer Distribution ◽  
Fine Resolution ◽  
Initialization Procedure

Abstract Bioluminescence (BL) predictability experiments (predictions of the intensity, depth, and distance offshore of the BL maximum) were conducted using an advective–diffusive tracer model with velocities and diffusivities from a fine-resolution model of the Monterey Bay, California, area. For tracer initialization, observations were assimilated into the tracer model while velocities and diffusivities were taken from the hydrodynamic model and kept unchanged during the initialization process. This dynamic initialization procedure provides an equilibrium tracer distribution that is balanced with the velocity and diffusivity fields from the hydrodynamic model. This equilibrium BL distribution was used as the initial BL field for 3 days of prognostic calculations. Two cross-shore surveys of bioluminescence data conducted at two locations (north of the bay and inside the bay) were used in four numerical experiments designed to estimate the limits of bioluminescence predictions by tracers. The cross-shore sections extended to around 25 km offshore, they were around 30 m deep, and on average they were approximately 35 km apart from each other. Bioluminescence predictability experiments demonstrated a strong utility of the tracer model (combined with limited bioluminescence observations and with the output from a circulation model) in predicting (over a 72-h period and over 25–35-km distances) the location and intensity of the BL maximum. Analysis of the model velocity fields and observed and model-predicted bioluminesence fields shows that the BL maximum is located in the frontal area representing a strong reversal of flow direction.

Sign in / Sign up

Export Citation Format

Share Document