Bikesharing and Bicycle Safety

The growth of bikesharing in the United States has had a transformative impact on urban transportation. Major cities have established large bikesharing systems, including Boston, Chicago, Denver, Minneapolis-Saint Paul, New York City, Salt Lake City, the San Francisco Bay Area, Seattle, Washington DC, and others. These systems began operating as early as 2010, and no fatalities have occurred within the US as of this writing. However, three have happened in North America—two in Canada and one in Mexico. Bikesharing has some qualities that appear inherently unsafe for bicyclists. Most prominently, helmet usage is documented to be quite low in most regions. Bikesharing is also used by irregular bicyclists who are less familiar with the local terrain. In this study, researchers take a closer look at bikesharing safety from qualitative and quantitative perspectives. Through a series of four focus groups, they discussed bikesharing usage and safety with bikesharing members and nonmembers in the Bay Area. They further engaged experts nationwide from a variety of fields to evaluate their opinions and perspectives on bikesharing and safety. Finally, researchers conducted an analysis of bicycle and bikesharing activity data, as well as bicycle and bikesharing collisions to evaluate injury rates associated with bikesharing when compared with benchmarks of personal bicycling. The data analysis found that collision and injury rates for bikesharing are lower than previously computed rates for personal bicycling. Experts and focus group participants independently pointed to bikesharing rider behavior and bikesharing bicycle design as possible factors. In particular, bikesharing bicycles are generally designed in ways that promote stability and limited speeds, which mitigate the conditions that contribute to collisions. Data analysis also explored whether there was evidence of a “safety in numbers benefit” that resulted from bikesharing activity. However, no significant impact from bikesharing activity on broader bicycle collisions could be found within the regions in which they operate. Discussion and recommendations are presented in the conclusion

Evaluation of influenza vaccine effectiveness and description of circulating strains in outpatient settings in South Africa, 2014

The effectiveness of the trivalent seasonal influenza vaccine during the 2014 season in South Africa was assessed using a test-negative case–control study design including 472 cases and 362 controls. Influenza A(H3N2) was the dominant strain circulating. The overall vaccine effectiveness estimate, adjusted for age and underlying conditions, was43.1% (95% CI: 26.8-74.5). 2014 H3N2 viruses from South Africa were mainly in sublineage 3C.3 with accumulation of amino acid changes that differentiate them from the vaccine strain in 3C.1

Afriflu2—Second international workshop on influenza vaccination in the African continent—8 November 2012, Cape Town (South Africa)

AbstractThe second meeting of the Afriflu conferences took place in Cape Town, South Africa, with over 60 participants from 15 countries in Africa and also outside the continent. Significant progress in surveillance has been made in better understanding the illness burden of influenza on the continent, which limited evidence suggests is greater than that in the developed world. In southern Africa HIV and TB coinfections play a major role in increasing hospitalisation and mortality, while elsewhere in Africa other cofactors still need to be determined.There is currently no indigenous vaccine production in sub-Saharan Africa and only one facility, based in South Africa, capable of filling imported bulk. Innovative vaccine strategies will need to be explored, such as maternal immunisation, and also the possibility of other influenza vaccine options, such as live attenuated influenza vaccine for young children. Sustained indigenous vaccine production is essential for the continent to have vaccine security in the event of a pandemic even though establishing local production faces considerable challenges especially ensuring adequate markets on the continent. There is an urgent need to develop effective communication messages for decision makers as well as healthcare workers addressing the importance of influenza even in the face of the major competing health burdens of the continent

Evaluation of influenza vaccine effectiveness and description of circulating strains in outpatient settings in South Africa, 2014

The effectiveness of the trivalent seasonal influenza vaccine during the 2014 season in South Africa was assessed using a test-negative case–control study design including 472 cases and 362 controls. Influenza A(H3N2) was the dominant strain circulating. The overall vaccine effectiveness estimate, adjusted for age and underlying conditions, was43.1% (95% CI: 26.8-74.5). 2014 H3N2 viruses from South Africa were mainly in sublineage 3C.3 with accumulation of amino acid changes that differentiate them from the vaccine strain in 3C.1

An assessment of the screening method to evaluate vaccine effectiveness: the case of 7-valent pneumococcal conjugate vaccine in the United States.

The screening method, which employs readily available data, is an inexpensive and quick means of estimating vaccine effectiveness (VE). We compared estimates of effectiveness of heptavalent pneumococcal conjugate vaccine (PCV7) against invasive pneumococcal disease (IPD) using the screening and case-control methods. Cases were children aged 19-35 months with pneumococcus isolated from normally sterile sites residing in Active Bacterial Core surveillance areas in the United States. Case-control VE was estimated for 2001-2004 by comparing the odds of vaccination among cases and community controls. Screening-method VE for 2001-2009 was estimated by comparing the proportion of cases vaccinated to National Immunization Survey-derived coverage among the general population. To evaluate the plausibility of screening-method VE findings, we estimated attack rates among vaccinated and unvaccinated persons. We identified 1,154 children with IPD. Annual population PCV7 coverage with ≥1 dose increased from 38% to 97%. Case-control VE for ≥1 dose was estimated as 75% against all-serotype IPD (annual range: 35-83%) and 91% for PCV7-type IPD (annual range: 65-100%). By the screening method, the overall VE was 86% for ≥1 dose (annual range: -240-70%) against all-serotype IPD and 94% (annual range: 62-97%) against PCV7-type IPD. As cases of PCV7-type IPD declined during 2001-2005, estimated attack rates for all-serotype IPD among vaccinated and unvaccinated individuals became less consistent than what would be expected with the estimated effectiveness of PCV7. The screening method yields estimates of VE that are highly dependent on the time period during which it is used and the choice of outcome. The method should be used cautiously to evaluate VE of PCVs

Research-to-Practice Brief: Promising Evidence that Early Head Start Can Prevent Child Maltreatment

This brief addresses two main questions in a sample of Early Head Start eligible children: 1) the number and type of maltreatment episodes and 2) the impact of Early Head Start on child and family involvement in the child welfare system. These findings are especially important given the lack of scalable and effective preventive interventions. In addition, they are also timely given the recent interest in fostering collaborations between early care and education programs and child welfare agencies, agencies responsible for overseeing child protection from maltreatment (OHS & ACYF, 2010; ACYF & OHS, 2011; ACYF & OCC, 2011). The current study represents a first look at the impact of Early Head Start on child maltreatment. We are continuing to collect data and will have more information in the upcoming years

It’s Not as Simple as it Sounds: Problems and Solutions in Accessing and Using Administrative Child Welfare Data for Evaluating the Impact of Early Childhood Interventions

In recent years, there has been increasing interest in using administrative data collected by state child welfare agencies as a source of information for research and evaluation. The challenges of obtaining access to and using these data, however, have not been well documented. This study describes the processes used to access child welfare records in six different states and the approach to combining and using the information gathered to evaluate the impact of the Early Head Start program on children’s involvement with the child welfare system from birth through age eleven. We provide “lessons learned” for researchers who are attempting to use this information, including being prepared for long delays in access to information, the need for deep understanding of how child welfare agencies record and code information, and for considerable data management work for translating agency records into analysis-ready datasets. While accessing and using this information is not easy, and the data have a number of limitations, we suggest that the benefits can outweigh the challenges and that these records can be a useful source of information for policy-relevant child welfare research

Hydrate-phobic surfaces: fundamental studies in clathrate hydrate adhesion reduction

Clathrate hydrate formation and subsequent plugging of deep-sea oil and gas pipelines represent a significant bottleneck for deep-sea oil and gas operations. Current methods for hydrate mitigation are expensive and energy intensive, comprising chemical, thermal, or flow management techniques. In this paper, we present an alternate approach of using functionalized coatings to reduce hydrate adhesion to surfaces, ideally to a low enough level that hydrodynamic shear stresses can detach deposits and prevent plug formation. Systematic and quantitative studies of hydrate adhesion on smooth substrates with varying solid surface energies reveal a linear trend between hydrate adhesion strength and the practical work of adhesion (γ[superscript total][1 + cos θ[subscript rec]]) of a suitable probe liquid, that is, one with similar surface energy properties to those of the hydrate. A reduction in hydrate adhesion strength by more than a factor of four when compared to bare steel is achieved on surfaces characterized by low Lewis acid, Lewis base, and van der Waals contributions to surface free energy such that the practical work of adhesion is minimized. These fundamental studies provide a framework for the development of hydrate-phobic surfaces, and could lead to passive enhancement of flow assurance and prevention of blockages in deep-sea oil and gas operations.Massachusetts Institute of Technology. Energy Initiative (Chevron Corporation)Massachusetts Institute of Technology. Dept. of Mechanical EngineeringNational Research Council (U.S.) (Postdoctoral Fellowship