Program Infrastructure the Key to Success: A Pilot Crosswalk Installation to Promote Walkability, Pedestrian Safety, and Physical Activity in the U.S. Virgin Islands

BACKGROUND & AIMS

While physical inactivity can contribute to chronic diseases, regular activity like walking can help prevent them. In 2010, one in three adults in the U.S. Virgin Islands (USVI) was physically inactive, higher than most U.S. states and territories. There are few walkable destinations and sidewalks along streets in the USVI. Since community- and street-scale design features can influence walking, we convened a 3-day walkability institute in the USVI to (1) learn about physical activity and best practices for design and (2) develop public health infrastructure that supports implementation. Island teams were formed to develop and implement a territory-wide action plan, focused on passing a Complete Streets policy, and demonstration projects on the islands of St. Croix, St. John, and St. Thomas to advance and pass this policy. An example of the demonstration projects and their significance is the completed one in St. Croix, which is the focus of this article.

METHODS

Island teams applied critical components of functioning program infrastructure as described in the Component Model of Infrastructure (CMI) such as engaged data, multilevel leadership, responsive plans and planning, and networked partnerships. We evaluated whether a crosswalk installation in St. Croix could alter driver and pedestrian behavior and create a safer environment for pedestrians. Observers recorded pedestrian crossing time, driver speed, and other behaviors before and after crosswalk installation.

RESULTS

Pedestrians took significantly fewer average seconds to cross the street in the postdemonstration period (9.83) compared with predemonstration (13.4) (p = .03). Average car speed declined between the predemonstration (24.3) and long-term demonstration periods (p < .01) and from the postdemonstration (24.7) to the long-term demonstration period (18.2) (p < .01). A greater percentage of pedestrians used the crosswalk to cross the street between the postdemonstration (12.5%) and long-term demonstration periods (53.7%) (p < .01).

IMPLICATIONS

The demonstration project in St. Croix shows that improvements to built environment infrastructure can increase safety for pedestrians, thus improving walkability in the USVI. We discuss the importance of CMI elements observed in the success of the St. Croix demonstration and its effectiveness in promoting a Complete Streets policy and the lack of these elements on St. John hindering progress there. Public health practitioners can apply the CMI to future physical activity promotion projects in the USVI and other settings as having functioning program infrastructure helps overcome challenges including natural disasters and a global pandemic and can achieve progress toward sustained policy and systems change.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Sampling Methodology and Reliability of a Representative Walkability Audit

Background

Physical inactivity is a public health concern in the US Virgin Islands (USVI). A contributing factor may be a lack of pedestrian infrastructure and other environmental supports for walking. In this manuscript, we describe the methods used to conduct a walkability audit of environmental features related to physical activity in the USVI.

Methods

In 2016, volunteer auditors conducted the audit using a modified version of the Microscale Audit of Pedestrian Streetscapes tool. A two-stage sampling method was developed using publicly available census data to select a sample of estates (n=46) and street segments (n=1,550; 99.2 km) across the USVI. A subset of segments was audited by two independent auditors, and inter-rater reliability was assessed using Cohen's kappa and percent agreement.

Results

Audits were completed on 1,114 segments (94.6 km), and estimates were weighted to represent accessible public street length in the study area (1,155.9 km). Most items on the audit tool (62.7%) demonstrated good to excellent reliability. We found that it was feasible to conduct a reliable audit of environmental features related to physical activity across a large sample of streets in the USVI.

Conclusions

These methods can be replicated in other settings to collect comprehensive data that can be used to guide strategies to improve the walkability of communities.

Community and Street-Scale Supports for Walking in the US Virgin Islands Before the 2017 Hurricanes

OBJECTIVES

To determine the prevalence of community and street-scale design features that promote walking across the US Virgin Islands (USVI).

METHODS

In May 2016, the USVI Department of Health, with technical assistance from the Centers for Disease Control and Prevention, conducted a territory-wide audit with a validated tool. We selected street segments (n = 1114) via a 2-stage sampling method, and estimates were weighted to be representative of publicly accessible street length.

RESULTS

Overall, 10.7% of the street length contained a transit stop, 11.3% had sidewalks, 21.7% had at least 1 destination (e.g., stores, restaurants), 27.4% had a traffic calming feature (e.g., speed humps), and 53.2% had at least some street lighting. Several features were less prevalent on residential streets compared with commercial streets, including transit stops, sidewalks, destinations, and street lighting (P < .01).

CONCLUSIONS

Across the USVI, community and street-scale features supportive of walking were uncommon. Improving community and street-scale design in the USVI, particularly in residential areas, could increase physical activity by enhancing walkability and therefore improve public health. These data can be used to inform community planning in the USVI.

Successful long-term outcome of liver transplantation in late-onset lysosomal acid lipase deficiency

Late-onset LAL deficiency, previously referred to as cholesteryl ester storage disorder, is a rare lysosomal storage disorder characterized by accumulation of cholesteryl esters. It has a heterogeneous clinical phenotype including abdominal pain, poor growth, hyperlipidemia with vascular complications and hepatosplenomegaly. End-stage liver disease may occur, but there are few reports of successful LT. There are also concerns that systemic manifestations of the disease might persist post-LT. We report a case with excellent outcome eight yr following LT. The subject was noted to have asymptomatic hepatosplenomegaly during an intercurrent illness, and LAL deficiency was confirmed with compound heterozygosity in the LIPA. Despite dietary fat restriction, he developed signs of progressive liver disease and subsequently developed hepatopulmonary syndrome. He underwent cadaveric LT at the age of nine and a half yr and recovered with prompt resolution of hepatopulmonary syndrome. Eight yr post-transplant he has normal growth, normal lipid profile, and liver and renal function tests. Liver histology showed no evidence of disease recurrence at this stage. LT in this subject resulted in an excellent functional correction of late-onset LAL deficiency.

Relation between drug-induced central nervous system effects and plasma levels of diazepam in man

Pharmacodynamic effects and plasma levels of diazepam were studied in healthy male volunteers at different dose levels. Responses to diazepam were quantified, using instruments which measured body sway (statometry) and psychomotor performance (stressalyser tests). High dose-related correlations were obtained between drug-induced changes in test parameters and drug plasma levels, both with regard to stimulant and depressive effects. Techniques were devised for evaluating and comparing the efficacy and usefulness of different types of tests, taking into account critical thresholds, slopes and error estimates, correcting for changes in predrug levels and control (nondrug) trials.

Mechanism of loosening of the Souter-Strathclyde total elbow replacement evidence from revision surgery

Nine Souter-Strathclyde humeral and ulnar components retrieved from revision surgery for aseptic loosening were examined macro- and microscopically. The wear patterns were compared and photographed. Humeral components demonstrated no evidence of wear. All ulnar components exhibited similar wear patterns. Six of the nine exhibited macroscopic evidence taking the form of deep linear grooves on either the medial or lateral articulating surfaces. Microscopic examinations revealed wear on all nine, exhibited as disruption of the polyethylene machining lines on the articular surfaces, but almost complete preservation on the central gliding ridge. We believe our observations are explained by 'rocking' of the humeral component on the ulnar as a result of the congruent surfaces of the Souter-Strathclyde prosthesis, which resist rotational and translational movements, characteristic of the normal elbow.

In vitro study investigating the mechanical properties of acrylic bone cement containing calcium carbonate nanoparticles

A successful total hip replacement has an expected service life of 10-20 years with over 75% of failures due to aseptic loosening which is directly related to cement mantle failure. The aim of the present study was to investigate the addition of nanoparticles of calcium carbonate to acrylic bone cement. It was anticipated that an improvement in mechanical performance of the resultant nanocomposite bone cement would be achieved. A design of experiment approach was adopted to maximise the mechanical properties of the bone cement containing nanoparticles of calcium carbonate and to determine the constituents and preparation methods for which these occur. The selected conditions provided improvements of 21% in energy to maximum load, 10% in elastic modulus, 7% in bending strength and 8% in bending modulus when compared with bone cement without nanoparticles. Although cement containing nanoCaCO(3) coated in sodium citrate also enhanced the energy to maximum load by 28% and the elastic modulus by 14% when compared with control cement, it is not recommended as a factor in the production of nanocomposite bone cement due to reduction in the bending properties of the final bone cement.

The influence of wear paths produced by hip replacement patients during normal walking on wear rates

Variation in wear paths is known to greatly affect wear rates in vitro, with multidirectional paths producing much greater wear than unidirectional paths. This study investigated the relationship between multidirectional motion at the hip joint, as measured by aspect ratio, sliding distance, and wear rate for 164 hip replacements. Kinematic input from three-dimensional gait analysis was used to determine the wear paths. Activity cycles were determined for a subgroup of 100 patients using a pedometer study, and the relationship between annual sliding distance and wear rate was analyzed. Poor correlations were found between both aspect ratio and sliding distance and wear rate for the larger group and between annual sliding distance and wear rate for the subgroup. However, patients who experienced a wear rate <0.08 mm/year showed a strong positive correlation between the combination of sliding distance, activity levels, and aspect ratio and wear rate (adjusted r(2) = 55.4%). This group may represent those patients who experience conditions that most closely match those that prevail in simulator and laboratory tests. Although the shape of wear paths, their sliding distance, and the number of articulation cycles at the hip joint affect wear rates in simulator studies, this relationship was not seen in this clinical study. Other factors such as lubrication, loading conditions and roughness of the femoral head may influence the wear rate.

Evaluation of an accelerated aging medium for acrylic bone cement based on analysis of nanoindentation measurements on laboratory-prepared and retrieved specimens

The thrust of the study was a critical evaluation of the efficacy of a medium (30% v/v H(2)O(2), at 60 degrees C) that has been suggested in a literature report as being suitable for simulating the oxidative aging process, seen in vivo, in the acrylic bone cement mantles of total hip and knee joint replacements. For this purpose, quasi-static and dynamic nanoindentation measurements were used to obtain material properties--elastic modulus, E; hardness, H; and the variation of the storage and loss moduli with the frequency of the applied indenting force--of PalacosR acrylic bone cement specimens after various periods of immersion (7, 14, 21, and 28 days) in the aging solution, and of specimens prepared from cement mantles retrieved from cemented total hip joint replacements after various times in vivo (0.92-21 years). Also, best-fit relationships were obtained between E and time in the H(2)O(2) solution (t), H and t, E and in vivo time (T), and H and T. This body of results points to the possibility that the aging solution is effective, although the evidence is not conclusive.

Segregation of Beaufort Sea beluga whales during the open-water season

Population segregation by habitat use occurs because energy requirements and survival strategies vary with age, sex, size, and reproductive stage. From late summer to early fall in 1993, 1995, and 1997, relative length (age), sex, and reproductive status of satellite-tagged beluga whales ( Delphinapterus leucas (Pallas, 1776)) in the eastern Beaufort Sea were tested for habitat segregation. We used (i) resource selection function models to evaluate how belugas used areas of varying sea ice concentration and shelf habitat and (ii) distance analysis to measure the selection of areas varying in distance to mainland and island coastlines. Resource selection functions and distance analysis established that habitat selection differed with length, sex, and reproductive status of whales: (i) females with calves and smaller males selected open-water habitats near the mainland; (ii) large males selected closed sea ice cover in and near the Arctic Archipelago; and (iii) smaller males and two females with calves (not newborn) selected habitat near the ice edge. The segregation of habitat use according to sex, age, and reproductive status relates to the different resources required at different life stages and may represent characteristics of beluga social structure. We discuss our results in the context of two common sexual segregation hypotheses and conclude that summer habitat segregation of belugas reflects differences in foraging ecology, risk of predation, and reproduction.

Critical comparison of two methods for the determination of nanomechanical properties of a material: Application to synthetic and natural biomaterials

Two methods used for determining the elastic modulus (E) and hardness (H) of a material--the original version of the well-known Oliver-Pharr Method, OOPM, and a variant of it called the Modified Slopes Method, MSM--were critically compared. The nanoindentation test results, of indenter load-versus-indenter displacement, were recorded for six series of specimens, three of commercially-available acrylic bone cements (Palacos R and Cemex XL) and three of bones (human, bovine, and mouse). In the first series, the specimens were prepared from Palacos R cement mantles retrieved from cemented total hip joint replacements after 11 months, 11 years, and 21 years in vivo. In the second and third series, the specimens were fabricated from hand- and vacuum-mixed dough of Cemex XL cement, respectively. In the fourth, fifth, and sixth series, the specimens were prepared from fresh frozen cortical bone of human tibia, plexiform bone from fresh bovine tibia, and femora from inbred mice, respectively. It was found that, for a given material, the values of E or H computed using OOPM and MSM are not significantly different. However, the recommendation is that MSM is preferable because it is straightforward-only the nanoindentation measurements and values of constants that depend on the geometry of the indenter used are needed. In contrast, when the OOPM is used, there is a critical input (the indenter tip area function), whose computation is problematic. The article also includes a succinct discussion of factors that affect the values of material properties computed from nanoindentation measurements, such as the loading rate and the surface roughness of the test specimen.

A comparison of different biogeographical classifications of Europe, Great Britain and Spain

Various biogeographical and bioclimatic classifications of a number of regions, countries and continents have been created to meet different objectives. A policy maker might ask the question 'why is there no single accepted classification and how do the different classifications compare with one another?' In order to answer these two questions three classifications created by different methods for Great Britain and two for Spain are compared using the Kappa statistic. All of the classifications were created from data on cellular grids with a set window size. Further non-statistical comparisons are made with other classifications. The biogeographic classifications studied in this paper produced three different types of zone: those that were always identified whatever the method; those that were broadly similar but where the boundaries differed; and those that were unique to a particular classification. These different types of zone are likely to exist for any comparison between classifications of a particular region. The extent of the geographic window from which data were obtained had a major effect on the classification of grid cells at the edges of the window. For example, the few grid cells in the south of England, with characteristics of continental Europe, are not detected if data from Great Britain alone are used for the classification. We conclude that the data window should always be larger than the area for which the classification is being made. The objective Kappa statistic, although useful, was not capable of discerning similarities and dissimilarities that appear obvious to the subjective human eye. Although the details of the classifications differed there were broad similarities between the classifications and these differences reflect important divisions along major environmental axes that have been inferred by earlier biogeographers. As the divisions are real there is a sound basis for their use in future land use or environmental policy.

Phase II trial of topotecan and cisplatin in persistent or recurrent squamous and nonsquamous carcinomas of the cervix

OBJECTIVE

Cisplatin is a standard treatment in advanced, recurrent cervical cancer. Because topotecan is an established treatment in gynecologic malignancies such as ovarian cancer and exhibits nonoverlapping toxicity with cisplatin, a phase II trial was conducted to evaluate the tolerability and antitumor activity of a cisplatin/topotecan doublet in persistent or recurrent cervical cancer patients.

METHODS

Patients with bidimensionally measurable persistent or recurrent squamous cell and non squamous cell cervical cancer and adequate bone marrow were enrolled. Patients received 50 mg/m(2) of cisplatin intravenously over 1 h on Day 1 and 0.75 mg/m(2) of topotecan intravenously over 30 min on Days 1, 2, and 3 of 21-day cycles for six cycles or until disease progression. Tumor response and regimen toxicity were assessed using established Gynecologic Oncology Group criteria.

RESULTS

Thirty-two of 35 enrolled patients were evaluable for toxicity and tumor response. All but 2 evaluable patients had received previous radiotherapy. No patient received prior chemotherapy. The cisplatin/topotecan doublet was well tolerated, with 77 and 78% of courses given without interruption or delay and at full doses, respectively. As anticipated, the most common toxicity was hematologic, with grade 3/4 neutropenia and thrombocytopenia reported in 30 and 10% of cycles, respectively. The overall response rate was 28% (9/32), with 3 complete and 6 partial responses. The antitumor response in nonirradiated fields (30%) was similar to the response observed in previously irradiated fields (33%), suggesting good drug penetration. Median duration of response was 5 months (range, 2 to 15+ months). An additional 9 (28%) patients achieved stable disease. Median survival was 10 months, with 3 patients in lasting remission.

CONCLUSIONS

These results demonstrate that the cisplatin/topotecan combination is safe, well tolerated, and active in persistent or recurrent cervical cancer patients. A phase III, multicenter trial is under way (cisplatin/topotecan versus cisplatin) based on these favorable results to confirm the safety and efficacy profile in this patient population.

Inequalities in health: evaluation and effectiveness in practice

This paper details the findings from a project that assessed the contribution made by nurses, midwives and health visitors to targeting health and social need. This is an important theme within the Northern Ireland Regional Strategy entitled 'Health and well-being into the next millennium: a regional strategy for health and social well-being 1997-2002', which is concerned with addressing inequalities in health status and social well-being. In response to this initial survey, the paper also highlights the second phase of the project that was the development of an evaluation manual specifically designed to assist health-care practitioners in establishing evaluation frameworks and in applying evaluation techniques and methods. The paper describes four research case studies that are intended to illustrate the kinds of evaluation methods necessary to cover the stages of evaluation, needs assessment, structure, process and outcome, and to reflect the experience of applied evaluation as it occurs in practice as opposed to how it appears in textbooks.

Bone cement mixing. Theatre staff's views and opinions

Acrylic bone cement has not substantially changed since it was first introduced more than 30 years ago, however the method by which it is mixed has evolved greatly (Dunne 1996).