A Population-Level Examination of Incarcerated Women and Mothers Before and After the California Public Safety Realignment Act

One way cities are looking to promote bicycling is by providing publicly or privately operated bike-share services, which enable individuals to rent bicycles for one-way trips. Although many studies have examined the use of bike-share services, little is known about how these services influence individual-level travel behavior more generally. In this study, we examine the behavior of users and non-users of a dockless, electric-assisted bike-share service in the Sacramento region of California. This service, operated by Jump until suspended due to the coronavirus pandemic, was one of the largest of its kind in the U.S., and spanned three California cities: Sacramento, West Sacramento, and Davis. We combine data from a repeat cross-sectional before-and-after survey of residents and a longitudinal panel survey of bike-share users with the goal of examining how the service influenced individual-level bicycling and driving. Results from multilevel regression models suggest that the effect of bike-share on average bicycling and driving at the population level is likely small. However, our results indicate that people who have used-bike share are likely to have increased their bicycling because of bike-share.

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SoftPSN: Software-Defined Resource Slicing for Low-Latency Reliable Public Safety Networks

Wireless Communications and Mobile Computing ◽

10.1155/2018/7253283 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Anteneh A. Gebremariam ◽

Muhammad Usman ◽

Riccardo Bassoli ◽

Fabrizio Granelli

Keyword(s):

Public Safety ◽

First Responders ◽

Base Station ◽

Low Latency ◽

Radio Resource ◽

Life Saving ◽

Before And After ◽

Simulation Results ◽

Emergency Scenarios ◽

Safety Applications

Achieving the low-latency constraints of public safety applications during disaster could be life-saving. In the context of public safety scenarios, in this paper, we propose an efficient radio resource slicing algorithm that enables first responders to deliver their life-saving activities effectively. We used the tool of stochastic geometry to model the base station distribution before and after a disaster. In addition, under this umbrella, we also proposed an example of public safety scenario, ultrareliable low-latency file sharing, via in-band device-to-device (D2D) communication. The example scenario is implemented in NS-3. The simulation results show that radio resource slicing and prioritization of first responders resources can ensure ultrareliable low-latency communication (URLLC) in emergency scenarios.

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Reflection on research methods: The before and after study.

10.21203/rs.2.15704/v1 ◽

2019 ◽

Author(s):

Mohammad Cheik-Hussein ◽

Ian Harris ◽

Adriane Lewin

Keyword(s):

Hip Fracture ◽

Study Design ◽

Secular Trend ◽

Population Level ◽

Control Group ◽

Fracture Failure ◽

Before And After ◽

Underlying Trend ◽

Before And After Study ◽

Actual Intervention

Abstract Background Before and after studies allow for the investigation of population-level health interventions and are a valuable study design in situations where randomisation is not feasible. The before and after study design involves measuring an outcome both before and after an intervention and comparing the outcome rates in both time periods to determine the effectiveness of the intervention. These studies do not involve a contemporaneous control group and must therefore take into account any underlying secular trends in order to separate the effect of the intervention from any pre-existing trend. Neglecting this important step can lead to spurious results.Methods To illustrate the importance of accounting for underlying trends, we performed a before and after study assessing 30-day mortality in hip fracture patients without any actual intervention, and instead designated an arbitrarily-chosen time-point as our ‘intervention’. We did this to ensure that we were basing our results exclusively on the underlying trend throughout the studied period and also to enable us to show that even an intervention of nothing may be spuriously interpreted to have an effect if the before and after study is incorrectly analysed. Results We found a secular trend in our data showing improving 30-day mortality in hip fracture patients in our institution. We then demonstrated that disregarding this underlying trend showed that our intervention of nothing ‘resulted’ in a significant decrease in mortality, from 6.7% in the ‘before’ period to 3.1% in the ‘after’ period (p<0.0008). This apparent impact on mortality disappeared when we accounted for the underlying trend in our analysis (IRR of 0.75, 95% CI 0.32 – 1.78; p=0.5). In the context of declining 30-day mortality following hip fracture, failure to consider the existing underlying trend lead us to believe that it was our ‘intervention’ that ‘caused’ the decrease in mortality in the ’after’ period compared to the ‘before’ period when our results clearly show that mortality was decreasing irrespective of any intervention.Conclusion Our study highlights the importance of appropriate measurement and consideration of underlying trends when analysing data from before and after studies and illustrates what can happen should researchers neglect this important step.

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Have Standard Formulas Correcting Correlations for Range Restriction Been Adequately Tested?: Minor Sampling Distribution Quirks Distort Them

Educational and Psychological Measurement ◽

10.1177/0013164417736092 ◽

2017 ◽

Vol 78 (6) ◽

pp. 1021-1055 ◽

Cited By ~ 1

Author(s):

Wendy Johnson ◽

Ian J. Deary ◽

Thomas J. Bouchard

Keyword(s):

Cognitive Ability ◽

Sample Selection ◽

Population Level ◽

Maximum Likelihood Estimates ◽

Range Restriction ◽

Data Set ◽

Wide Range ◽

Before And After ◽

Ability Tests ◽

Highly Correlated

Most study samples show less variability in key variables than do their source populations due most often to indirect selection into study participation associated with a wide range of personal and circumstantial characteristics. Formulas exist to correct the distortions of population-level correlations created. Formula accuracy has been tested using simulated normally distributed data, but empirical data are rarely available for testing. We did so in a rare data set in which it was possible: the 6-Day Sample, a representative subsample of 1,208 from the Scottish Mental Survey 1947 of cognitive ability in 1936-born Scottish schoolchildren (70,805). 6-Day Sample participants completed a follow-up assessment in childhood and were re-recruited for study at age 77 years. We compared full 6-Day Sample correlations of early-life variables with those of the range-restricted correlations in the later-participating subsample, before and after adjustment for direct and indirect range restriction. Results differed, especially for two highly correlated cognitive tests; neither reproduced full-sample correlations well due to small deviations from normal distribution in skew and kurtosis. Maximum likelihood estimates did little better. To assess these results’ typicality, we simulated sample selection and made similar comparisons using the 42 cognitive ability tests administered to the Minnesota Study of Twins Reared Apart, with very similar results. We discuss problems in developing further adjustments to offset range-restriction distortions and possible approaches to solutions.

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Paradoxical population resilience of a keystone predator to a toxic invasive species

Wildlife Research ◽

10.1071/wr19150 ◽

2020 ◽

Vol 47 (3) ◽

pp. 260

Author(s):

J. Sean Doody ◽

David Rhind ◽

Simon Clulow

Keyword(s):

Population Level ◽

Population Monitoring ◽

Cane Toad ◽

Keystone Predator ◽

Individual Effects ◽

Before And After ◽

Animal Communities ◽

Better Than ◽

Population Resilience

Abstract ContextThe invasive cane toad (Rhinella marina) has decimated populations of a keystone predator, the yellow-spotted monitor (Varanus panoptes), causing trophic cascades in Australian animal communities. Paradoxically, some V. panoptes populations coexist with toads. Demonstrating patterns in heterogeneous population-level impacts could reveal mechanisms that mediate individual effects, and provide managers with the ability to predict future impacts and assist in population recovery. AimsThe aim of the present study was to search for spatial patterns of population resilience of V. panoptes to invasive cane toads. MethodsPublished literature, unpublished data, reports and anecdotal information from trained herpetologists were used to test the emerging hypothesis that resilient predator populations are mainly coastal, whereas non-resilient populations are mostly inland. Key resultsPost-toad invasion data from 23 V. panoptes populations supported the idea that toad impacts on V. panoptes were heterogeneous; roughly half the populations could be designated as resilient (n=13) and half as non-resilient (n=10). Resilient populations had longer times since toad invasion than did non-resilient populations (39 versus 9 years respectively), supporting the idea that some recovery can occur. Non-resilient populations were exclusively inland (n=10), whereas resilient populations were split between inland (n=5) and coastal (n=8) populations. Resilient inland populations, however, were mainly confined to areas in which decades had passed since toad invasion. ConclusionsThe findings suggest that coastal V. panoptes populations fare much better than inland populations when it comes to surviving invading cane toads. ImplicationsUnambiguous recovery of monitor populations remains undemonstrated and will require long-term population monitoring before and after toad invasion.

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317: Population-level fetal growth outcomes before and after gestational diabetes treatment guideline change

American Journal of Obstetrics and Gynecology ◽

10.1016/j.ajog.2019.11.332 ◽

2020 ◽

Vol 222 (1) ◽

pp. S213

Author(s):

Esther Ellsworth Bowers ◽

Shannon Santo ◽

Bernadette O'Grady ◽

Sue E. Sarsam ◽

Suzanne Halt ◽

...

Keyword(s):

Gestational Diabetes ◽

Fetal Growth ◽

Treatment Guideline ◽

Population Level ◽

Diabetes Treatment ◽

Growth Outcomes ◽

Before And After

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The effects of non-pharmaceutical interventions on SARS-CoV-2 transmission in different socioeconomic populations in Kuwait: A modelling study

University of Toronto Journal of Public Health ◽

10.33137/utjph.v2i2.36995 ◽

2021 ◽

Vol 2 (2) ◽

Author(s):

Fatima Khadadah ◽

Abdullah A. Al-Shammari ◽

Ahmad Alhashemi ◽

Dari Alhuwail ◽

Bader Al-Saif ◽

...

Keyword(s):

Disease Transmission ◽

Reproduction Number ◽

Public Health Intervention ◽

Population Level ◽

Socioeconomic Groups ◽

Before And After ◽

Cross Transmission ◽

Community Transmission ◽

The Impact ◽

Pharmaceutical Interventions

Background: Aggressive non-pharmaceutical interventions (NPIs) may reduce transmission of SARS-CoV2. The extent to which these interventions are successful in stopping the spread have not been characterized in countries with distinct socioeconomic groups. We compared the effects of a partial lockdown on disease transmission among Kuwaitis (P1) and non-Kuwaitis (P2) living in Kuwait. Methods: We fit a metapopulation Susceptible-Exposed-Infectious-Recovered (SEIR) model to reported cases stratified by two groups to estimate the impact of a lockdown on the effective reproduction number (Re). We estimated the basic reproduction number (R0) for the transmission in each group and simulated the potential trajectories of an outbreak from the first recorded case of community transmission until 12 days after the lockdown. We estimated Re values of both groups before and after the lockdown, simulated the effect of these values on epidemic curves and explored a range of cross-transmission scenarios. Results: We estimate R0 at 1·06 (95% CI: 1·05-1·28) for P1 and 1·83 (1·58-2·33) for P2. On March 22nd, Re for P1 and P2 are estimated at 1·13 (1·07-1·17) and 1·38 (1·25-1·63) respectively. After the curfew had taken effect, Re for P1 dropped modestly to 1·04 (1·02-1·06) but almost doubled for P2 to 2·47 (1·98-3·45). Our simulated epidemic trajectories show that the partial curfew measure modestly reduced and delayed the height of the peak in P1, yet significantly elevated and hastened the peak in P2. Modest cross-transmission from P2 to P1 elevated the height of the peak in P1 and brought it forward in time closer to the peak of P2. Conclusion: Our results demonstrate that a lockdown can reduce SARS-CoV2 transmission in one subpopulation but accelerate it in another. At the population level, the consequences of lockdowns may vary across the socioeconomic spectrum. Any public health intervention needs to be sensitive to disparities within populations.

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Effect of the Work Zone Double-Fine Law in Texas

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1715-04 ◽

2000 ◽

Vol 1715 (1) ◽

pp. 24-29 ◽

Cited By ~ 1

Author(s):

Gerald L. Ullman ◽

Paul J. Carlson ◽

Nada D. Trout

Keyword(s):

Public Safety ◽

Field Studies ◽

Work Zone ◽

Work Zones ◽

Citation Data ◽

Short Term ◽

Texas Department ◽

Before And After ◽

The Law ◽

External Reasons

Results of research conducted to investigate the short-term effects of the double-fine law in work zones implemented in Texas on January 1, 1998, are presented. Field studies of traffic speeds in several work zones were performed before and after the law was implemented. Traffic citation data for these same work zones were also obtained from the Texas Department of Public Safety. Analyses showed that traffic speeds in the work zones 4 to 6 months after the law was enacted were essentially unchanged from before the law was enacted. Similarly, citation frequency and fines levied were not significantly higher than they were before enactment of the law. The data suggested that a higher proportion of drivers who were issued citations after the law was implemented chose to take defensive driving training and to have the ticket subsequently dismissed. However, researchers could not determine whether this was due to the increased fine or to other external reasons.

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Population-level sexual behaviours in adolescent girls before and after introduction of the human papillomavirus vaccine (2003–2013)

Canadian Medical Association Journal ◽

10.1503/cmaj.180628 ◽

2018 ◽

Vol 190 (41) ◽

pp. E1221-E1226 ◽

Cited By ~ 10

Author(s):

Gina S. Ogilvie ◽

Felicia Phan ◽

Heather N. Pedersen ◽

Simon R. Dobson ◽

Monika Naus ◽

...

Keyword(s):

Human Papillomavirus ◽

Adolescent Girls ◽

Population Level ◽

Human Papillomavirus Vaccine ◽

Sexual Behaviours ◽

Before And After ◽

Papillomavirus Vaccine

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Metabolomic Variation Aligns with Two Geographically Distinct Subpopulations of Brachypodium Distachyon before and after Drought Stress

Cells ◽

10.3390/cells10030683 ◽

2021 ◽

Vol 10 (3) ◽

pp. 683

Author(s):

Aleksandra Skalska ◽

Manfred Beckmann ◽

Fiona Corke ◽

Gulsemin Savas Tuna ◽

Metin Tuna ◽

...

Keyword(s):

Drought Stress ◽

High Resolution Mass Spectrometry ◽

Brachypodium Distachyon ◽

Principal Component ◽

Population Level ◽

Tca Cycle ◽

Genomic Variation ◽

Climatic Regions ◽

Before And After ◽

Model Grass

Brachypodium distachyon (Brachypodium) is a non-domesticated model grass that has been used to assess population level genomic variation. We have previously established a collection of 55 Brachypodium accessions that were sampled to reflect five different climatic regions of Turkey; designated 1a, 1c, 2, 3 and 4. Genomic and methylomic variation differentiated the collection into two subpopulations designated as coastal and central (respectively from regions 1a, 1c and the other from 2, 3 and 4) which were linked to environmental variables such as relative precipitation. Here, we assessed how far genomic variation would be reflected in the metabolomes and if this could be linked to an adaptive trait. Metabolites were extracted from eight-week-old seedlings from each accession and assessed using flow infusion high-resolution mass spectrometry (FIE-HRMS). Principal Component Analysis (PCA) of the derived metabolomes differentiated between samples from coastal and central subpopulations. The major sources of variation between seedling from the coastal and central subpopulations were identified. The central subpopulation was typified by significant increases in alanine, aspartate and glutamate metabolism and the tricarboxylic acid (TCA) cycle. Coastal subpopulation exhibited elevated levels of the auxin, indolacetic acid and rhamnose. The metabolomes of the seedling were also determined following the imposition of drought stress for seven days. The central subpopulation exhibited a metabolomic shift in response to drought, but no significant changes were seen in the coastal one. The drought responses in the central subpopulation were typified by changes in amino acids, increasing the glutamine that could be functioning as a stress signal. There were also changes in sugars that were likely to be an osmotic counter to drought, and changes in bioenergetic metabolism. These data indicate that genomic variation in our Turkish Brachypodium collection is largely reflected as distinctive metabolomes (“metabolotypes”) through which drought tolerance might be mediated.

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