Serial and parallel organ-at-risk-specific noncoplanar arc optimization for small versus large target volumes in liver SBRT.

Noncoplanar arc optimization has been shown to reduce OAR doses in SRS/SRT and has the potential to reduce doses to OARs in SBRT. Extracranial targets have additional considerations, including large OARs and, in the case of the liver, volume constraints on the healthy liver. Considering pathlengths through OARs that encompass target volumes may lead to specific dose reductions as in the encompassing healthy liver tissue. These optimizations must also leverage delivery efficiency and trajectory sampling to ensure ease of clinical translation. The purpose of this research is to generate optimized static-couch arcs that separately consider serial and parallel OARs and arc delivery efficiency, with a trajectory sampling metric, towards the aim of reducing dose to OARs and the surrounding healthy liver tissue. Separate BEV cost maps were created for parallel, and serial OARs by means of a fast ray-triangle intersection algorithm. An additional BEV cost map was created for the liver which, by definition, encompasses the liver tumors. The individual costs of these maps were summed and combined with the sampling metric for 100 000 random combinations of arc trajectories. A search algorithm was applied to find an arc trajectory solution that satisfied BEV cost and sampling optimization, while also ensuring an efficient delivery was possible with a low number of arcs. This method of arc selection was evaluated for 16 liver SBRT patients characterized by small and large target volumes. Comparisons were made with a clinical arc template of coplanar arcs. Dosimetric plan quality was evaluated using published guidelines and metrics from RTOG1112. Four of five plan quality metrics for the liver were significantly reduced when planned with optimized noncoplanar arcs. Median (range) reductions of the volumes receiving 10, 18, and 21 Gy were found of 140.4 (295.8) cc (p = 0.001), 28.2 (230.6) cc (p = 0.002) and 18.5 (155.5) cc (p = 0.04). A significant increase in median (range) dose to the right kidney of 0.2 ± 0.9 Gy (p = 0.03) was also found using optimized noncoplanar arcs, which was below the tolerance of 10 Gy for all cases. The average number of arcs chosen was 4 ± 1. Optimizing serial and parallel OARs separately during static couch noncoplanar arc selection significantly reduced the dose to the liver during SBRT using a moderate number of arcs.

Outcomes of the roll-in cohort of the Amulet IDE trial of left atrial appendage occlusion.

Background: Left atrial appendage (LAA) occlusion is an alternative therapy to oral anticoagulants to reduce stroke risk in patients with nonvalvular atrial fibrillation (NVAF). The Amulet IDE trial compared the Amplatzer™ Amulet™ occluder (Abbott) with the Watchman™ 2.5 device (Boston Scientific) for LAA occlusion in patients with NVAF. Objective: The purpose of this study was to describe outcomes of the Amulet IDE trial roll-in cohort. Methods: At US sites up to 3 patients per implanter could be implanted with the Amulet occluder in the roll-in phase. The primary Endpoints in the Amulet IDE trial included safety (composite of procedure-related complications, all-cause death, or major bleeding at 12 months), effectiveness (composite of ischemic stroke or systemic embolism at 18 months), and rate of LAA occlusion at 45 days. Results: A total of 201 roll-in patients were enrolled. Device success occurred in 99% of patients, and device closure (residual jet ≤5 mm) was observed in 98.9% of patients at 45 days. The safety endpoint rate was numerically higher (worse) in the roll-in cohort compared to the randomized Amulet occluder cohort (18.4% vs 14.5%). Six patients (3.1%) experienced an ischemic stroke and 0 patients with a systemic embolism within 18 months, which was similar to the primary effectiveness endpoint rate in the randomized Amulet occluder cohort (2.8%). Conclusions: Despite lack of experience of the operators with the Amulet occluder in the roll-in phase, device implant success was high, a high rate of device closure was achieved, and low stroke rates were observed in patients with NVAF.

Evaluation of parent and youth experiences in advisory groups as part of a mental healthcare clinical trial: protocol for a mixed-method study.

INTRODUCTION: Patient engagement in healthcare research is a necessity to ensure that research objectives align with priorities, outcomes and needs of the population under study, and to facilitate ease of implementation and adoption of findings. In clinical trials, there is an increasing focus on patient engagement during the planning and conduct of clinical trials due to the potential for ethical and methodological benefits. As patient engagement in clinical trials increases, there is a need to evaluate the approaches of these activities to contribute evidence on what is most appropriate and successful. The purpose of this study is to evaluate patient engagement processes and the activities of patient partners during and after a paediatric mental healthcare trial. METHODS AND ANALYSIS: Using a mixed-methods study design, we will evaluate patient partners' engagement activities across set time-points during the trial and after trial completion. In this study, the term 'patient partner' is inclusive of two groups of people with lived experience: (1) caregivers (parents, formal/informal caregivers and family), and (2) youth (aged 15-24 years). Engagement will be evaluated using the participant and project questionnaires of the Public and Patient Engagement Evaluation Tool (PPEET), followed sequentially by semi-structured interviews. Quantitative data from the PPEET questionnaire will be analysed and reported using descriptive statistics. Data from open-ended questions from the PPEET questionnaires and semi-structured interviews will be analysed using thematic analysis. ETHICS AND DISSEMINATION: Approval from Athabasca University Research Ethics Board will be obtained for this project. Findings will be disseminated at both academic and public venues whether in-person or online, and using platforms that are caregiver and youth friendly. TRIAL REGISTRATION NUMBER: NCT04902391.

An Innovative Model of Pediatric Emergency Department Mental Health Care: Protocol for a Multicenter Type 1 Effectiveness-Implementation Cluster Randomized Trial.

Over the past decade, visits to American and Canadian emergency departments (EDs) for child and youth mental health care have increased substantially.1,2 Acute mental health crises can occur as a result of a variety of concerns, including those that are life threatening (eg, suicide attempts), pose safety concerns (eg, suicidal intentions, aggressive behaviors, alcohol and other drug use), and are physically distressing to the child or youth (eg, panic attacks). ED health care providers play a vital role in assessing the safety and well-being of the child or youth and referring them to services for ongoing care.3,4 During the ED visit, assessment and care should pinpoint risks, inform treatment, and consider family needs and preferences as part of a patient-centered approach. Yet, this approach to care is not widely adopted in EDs. Most EDs do not require the use of pediatric-specific mental health tools to guide assessments or have patient-centered procedures in place to guide the care of patients with mental health emergencies.5-7 Our team believes these limitations have led to the provision of acute mental health care that can lack sufficient quality and efficiency. This study protocol describes a trial designed to evaluate if a novel mental health care bundle that was co-designed with parents and youth results in greater improvements in the well-being of children and youth 30 days after seeking ED care for mental health and/or substance misuse concerns compared with existing care protocols. We hypothesize that the bundle will positively impact child and youth well-being, while also providing cost-effective health care system benefits.

Amplatzer Amulet Left Atrial Appendage Occluder Versus Watchman Device for Stroke Prophylaxis (Amulet IDE): A Randomized, Controlled Trial.

BACKGROUND: Percutaneous closure of the left atrial appendage (LAA) is an alternative to chronic oral anticoagulation to reduce stroke risk in patients with nonvalvular atrial fibrillation. The Amulet IDE trial (Amplatzer Amulet Left Atrial Appendage Occluder IDE Trial) was designed to evaluate the safety and effectiveness of the dual-seal mechanism of the Amulet LAA occluder compared with the Watchman device. METHODS: Patients with nonvalvular atrial fibrillation at increased risk of stroke were randomly assigned (1:1) to undergo percutaneous implantation of a LAA occluder with the Amulet occluder or Watchman device. The primary end points included safety (composite of procedure-related complications, all-cause death, or major bleeding at 12 months), effectiveness (composite of ischemic stroke or systemic embolism at 18 months), and the rate of LAA occlusion at 45 days. Prespecified secondary end points included a composite of all stroke, systemic embolism, or cardiovascular/unexplained death at 18 months, major bleeding at 18 months, and superiority test of the 3 primary end points. RESULTS: A total of 1878 patients were enrolled. The Amulet occluder was noninferior to the Watchman device for the primary safety end point (14.5% versus 14.7%; difference=-0.14 [95% CI, -3.42 to 3.13]; P<0.001 for noninferiority). Major bleeding and all-cause death were similar between groups (10.6% versus 10.0% and 3.9% versus 5.1%, respectively). Procedure-related complications were higher for the Amulet occluder (4.5% versus 2.5%), largely related to more frequent pericardial effusion and device embolization. The Amulet occluder was noninferior to the Watchman device for the primary effectiveness end point (2.8% versus 2.8%; difference=0.00 [95% CI, -1.55 to 1.55]; P<0.001 for noninferiority), and the composite of stroke, systemic embolism, or cardiovascular/unexplained death (5.6% versus 7.7%, difference=-2.12 [95% CI, -4.45 to 0.21]; P<0.001 for noninferiority). The rate of major bleeding was similar between groups (11.6% versus 12.3%; difference=-0.71 [95% CI, -3.72 to 2.31]; P=0.32 for superiority). LAA occlusion was higher for the Amulet occluder than for the Watchman device (98.9% versus 96.8%; difference=2.03 [95% CI, 0.41-3.66]; P<0.001 for noninferiority; P=0.003 for superiority). CONCLUSIONS: The Amulet occluder was noninferior for safety and effectiveness of stroke prevention for nonvalvular atrial fibrillation compared with the Watchman device and superior for LAA occlusion. Procedure-related complications were higher with the Amulet occluder and decreased with operator experience. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02879448.

University physicists and the origins of the National Physical Laboratory, 1830-1900.

Traditionally, historians have taken it for granted that Britain's National Physical Laboratory (NPL) was created as the result of demands from a "professional" body of university-based physicists for a state-funded scientific institution. Yet paying detailed attention to the history of the NPL's originating institution, Kew Observatory, shows that the story is not so clear-cut. Starting in the 1850s, Kew Observatory was partly a center for testing meteorological instruments and other scientific equipment in return for fees. Long after the 1850s, the observatory was run by self-funded devotees of science. Paid university physicists only assumed a dominant role on its governing committee in the last two decades of the nineteenth century, by which time instrument-testing was already the observatory's main role. This paper argues that the rise of the university physicists - together with the desire of some of these physicists for a national institution that tested electrical standards - can only partially explain the origins of the NPL, and that Kew was in some ways a national physical laboratory before there were many physics teaching posts in British universities. This paper is a case study that illustrates a need to reassess the importance of university physicists in shaping British science at the end of the nineteenth century.

PEMIP: Post-fire erosion model inter-comparison project.

Land managers often need to predict watershed-scale erosion rates after disturbance or other land cover changes. This study compared commonly used hillslope erosion models to simulate post-fire sediment yields (SY) at both hillslope and watershed scales within the High Park Fire, Colorado, U.S.A. At hillslope scale, simulated SY from four models- RUSLE, AGWA/KINEROS2, WEPP, and a site-specific regression model-were compared to observed SY at 29 hillslopes. At the watershed scale, RUSLE, AGWA/KINEROS2, and WEPP were applied to simulate spatial patterns of SY for two 14-16 km2 watersheds using different scales (0.5-25 ha) of hillslope discretization. Simulated spatial patterns were compared between models and to densities of channel heads across the watersheds. Three additional erosion algorithms were implemented within a land surface model to evaluate effects of parameter uncertainty. At the hillslope scale, SY was only significantly correlated to observed SY for the empirical model, but at the watershed scale, sediment loads were significantly correlated to observed channel head densities for all models. Watershed sediment load increased with the size of the hillslope sub-units due to the nonlinear effects of hillslope length on simulated erosion. SY's were closest in magnitude to expected watershed-scale SY when models were divided into the smallest hillslopes. These findings demonstrate that current erosion models are fairly consistent at identifying areas with low and high erosion potential, but the wide range of predicted SY and poor fit to observed SY highlight the need for better field observations and model calibration to obtain more accurate simulations.

Rationale and design for AMPLATZER Amulet Left Atrial Appendage Occluder IDE randomized controlled trial (Amulet IDE Trial).

The Amulet IDE Trial is an ongoing, prospective, randomized, multi-national trial, designed to evaluate the safety and effectiveness of the AMPLATZER Amulet Left Atrial Appendage Occluder for stroke prevention in comparison to the WATCHMAN Left Atrial Appendage Closure Device in patients with non-valvular atrial fibrillation. METHODS: Non-valvular atrial fibrillation patients at high risk of stroke (CHADS2 score ≥2 or a CHA2DS2-VASc score of ≥3) who are suitable candidates for left atrial appendage occlusion (LAAO) will be fully informed and requested to participate in the trial. A total of 1878 patients at up to 150 sites worldwide will be randomized in a 1:1 ratio between the AMPLATZER Amulet device (investigational) and the Boston Scientific WATCHMAN device (control). Each patient will be followed for 5 years, with follow-up assessments at discharge, 45 days, 3, 6, 9, 12, 18, and 24 months and then annually. The trial has three primary endpoints: A composite of procedure-related complications, or all-cause death, or major bleeding through 12 months (safety); a composite of ischemic stroke or systemic embolism through 18 months (effectiveness); and effective device LAAO, defined as residual jet around the device ≤5 mm at the 45-day visit (mechanism of action). SUMMARY: The Amulet IDE Trial is the first randomized head-to-head LAAO device trial and will provide data for the AMPLATZER Amulet occluder in a population with a high risk of stroke and bleeding.

The origins and early years of the Magnetic and Meteorological department at Greenwich Observatory, 1834-1848.

As one of his first acts upon becoming Astronomer Royal in 1835, George Airy made moves to set up a new observatory at Greenwich to study the Earth's magnetic field. This paper uses Airy's correspondence to argue that, while members of the reform movement in British science were putting pressure on the Royal Observatory to branch out into geomagnetism and meteorology, Airy established the magnetic observatory on his own initiative, ahead of Alexander von Humboldt's request for British participation in the worldwide magnetic charting project that later became known as the 'Magnetic Crusade'. That the Greenwich magnetic observatory did not become operational until 1839 was due to a series of incidental factors that provide a case study in the technical and political obstacles to be overcome in building a new government observatory. Airy attached less importance to meteorology than he did to geomagnetism. In 1840, he set up a full programme of meteorological observations at Greenwich - and thus turned his magnetic observatory into the 'Magnetic and Meteorological department' - only as the price of foiling an attempt by Edward Sabine and others in the London scientific elite to found a rival magnetic and meteorological observatory. Studying the origins of Airy's Magnetic and Meteorological department highlights how important the context of other institutions and trends in science is to understanding the development of Britain's national observatory.

Cost-effectiveness of percutaneous patent foramen ovale closure as secondary stroke prevention.

OBJECTIVE: Compared to medical therapy alone, percutaneous closure of patent foramen ovale (PFO) further reduces risk of recurrent ischemic strokes in carefully selected young to middle-aged patients with a recent cryptogenic ischemic stroke. The objective of this study was to evaluate the cost-effectiveness of this therapy in the context of the United Kingdom (UK) healthcare system. METHODS: A Markov cohort model consisting of four health states (Stable after index stroke, Post-Minor Recurrent Stroke, Post-Moderate Recurrent Stroke, and Death) was developed to simulate the economic outcomes of device-based PFO closure compared to medical therapy. Recurrent stroke event rates were extracted from a randomized clinical trial (RESPECT) with a median of 5.9-year follow-up. Health utilities and costs were obtained from published sources. One-way and probabilistic sensitivity analyses (PSA) were performed to assess robustness. The model was discounted at 3.5% and reported in 2016 Pounds Sterling. RESULTS: Compared with medical therapy alone and using a willingness-to-pay (WTP) threshold of £20,000, PFO closure reached cost-effectiveness at 4.2 years. Cost-effectiveness ratios (ICERs) at 4, 10, and 20 years were £20,951, £6,887, and £2,158, respectively. PFO closure was cost-effective for 89% of PSA iterations at year 10. Sensitivity analyses showed that the model was robust. CONCLUSIONS: Considering the UK healthcare system perspective, percutaneous PFO closure in cryptogenic ischemic stroke patients is a cost-effective stroke prevention strategy compared to medical therapy alone. Its cost-effectiveness was driven by substantial reduction in recurrent strokes and patients' improved health-related quality-of-life.

Long-Term Outcomes of Patent Foramen Ovale Closure or Medical Therapy after Stroke.

BACKGROUND: Whether closure of a patent foramen ovale reduces the risk of recurrence of ischemic stroke in patients who have had a cryptogenic ischemic stroke is unknown. METHODS: In a multicenter, randomized, open-label trial, with blinded adjudication of end-point events, we randomly assigned patients 18 to 60 years of age who had a patent foramen ovale (PFO) and had had a cryptogenic ischemic stroke to undergo closure of the PFO (PFO closure group) or to receive medical therapy alone (aspirin, warfarin, clopidogrel, or aspirin combined with extended-release dipyridamole; medical-therapy group). The primary efficacy end point was a composite of recurrent nonfatal ischemic stroke, fatal ischemic stroke, or early death after randomization. The results of the analysis of the primary outcome from the original trial period have been reported previously; the current analysis of data from the extended follow-up period was considered to be exploratory. RESULTS: We enrolled 980 patients (mean age, 45.9 years) at 69 sites. Patients were followed for a median of 5.9 years. Treatment exposure in the two groups was unequal (3141 patient-years in the PFO closure group vs. 2669 patient-years in the medical-therapy group), owing to a higher dropout rate in the medical-therapy group. In the intention-to-treat population, recurrent ischemic stroke occurred in 18 patients in the PFO closure group and in 28 patients in the medical-therapy group, resulting in rates of 0.58 events per 100 patient-years and 1.07 events per 100 patient-years, respectively (hazard ratio with PFO closure vs. medical therapy, 0.55; 95% confidence interval [CI], 0.31 to 0.999; P=0.046 by the log-rank test). Recurrent ischemic stroke of undetermined cause occurred in 10 patients in the PFO closure group and in 23 patients in the medical-therapy group (hazard ratio, 0.38; 95% CI, 0.18 to 0.79; P=0.007). Venous thromboembolism (which comprised events of pulmonary embolism and deep-vein thrombosis) was more common in the PFO closure group than in the medical-therapy group. CONCLUSIONS: Among adults who had had a cryptogenic ischemic stroke, closure of a PFO was associated with a lower rate of recurrent ischemic strokes than medical therapy alone during extended follow-up. (Funded by St. Jude Medical; RESPECT ClinicalTrials.gov number, NCT00465270 .).

Return on investment from fuel treatments to reduce severe wildfire and erosion in a watershed investment program in Colorado.

A small but growing number of watershed investment programs in the western United States focus on wildfire risk reduction to municipal water supplies. This paper used return on investment (ROI) analysis to quantify how the amounts and placement of fuel treatment interventions would reduce sediment loading to the Strontia Springs Reservoir in the Upper South Platte River watershed southwest of Denver, Colorado following an extreme fire event. We simulated various extents of fuel mitigation activities under two placement strategies: (a) a strategic treatment prioritization map and (b) accessibility. Potential fire behavior was modeled under each extent and scenario to determine the impact on fire severity, and this was used to estimate expected change in post-fire erosion due to treatments. We found a positive ROI after large storm events when fire mitigation treatments were placed in priority areas with diminishing marginal returns after treating >50-80% of the forested area. While our ROI results should not be used prescriptively they do show that, conditional on severe fire occurrence and precipitation, investments in the Upper South Platte could feasibly lead to positive financial returns based on the reduced costs of dredging sediment from the reservoir. While our analysis showed positive ROI focusing only on post-fire erosion mitigation, it is important to consider multiple benefits in future ROI calculations and increase monitoring and evaluation of these benefits of wildfire fuel reduction investments for different site conditions and climates.

An evaluation of a structured learning program as a component of the clinical practicum in undergraduate nurse education: A repeated measures analysis.

BACKGROUND: There is evidence that nursing students experience stress and anxiety and a reduction in self-efficacy when undertaking clinical placements. Previous reports have identified that a structured three-day program within the Bachelor of Nursing (BN) clinical practicum reduces the students self-report of anxiety and increases self-efficacy. However, it is unreported whether these improved outcomes are sustained for the duration of the clinical placement. OBJECTIVE: The aim of this study was to evaluate the duration of the effect of a three-day structured learning program within the clinical placement on final year Bachelor of Nursing student's report of anxiety and self-efficacy pre- and post-program participation in this intervention and following completion of the clinical practicum. DESIGN: A repeated measures design. SETTING: University-based Clinical School of Nursing, acute care clinical practicum. PARTICIPANTS: Final year Bachelor of Nursing students. METHODS: The intervention comprised the three-day program on starting the clinical practicum. A questionnaire included the anxiety subscale of The Hospital Anxiety & Depression Scale (The HAD) and the General Self-Efficacy Scale (GSES-12). The questionnaire was completed on day one (time one), upon completion of the three-day program (time two) and upon completion of placement on day 18 (time three). RESULTS: The questionnaire response rate varied over time. There was a statistically significant effect in reducing anxiety over time: F(1.73,74.46)=25.20, p<0.001 and increasing self-efficacy over time F(1.32,41.04)=7.72, p<0.004. CONCLUSIONS: This is the first report that we are aware of that has measured final year Bachelor of Nursing student's report of both anxiety and self-efficacy over repeated measures of time. Students continue to benefit from a structured learning program and the benefit of the intervention is sustained for the clinical placement duration.

Making Kew Observatory: the Royal Society, the British Association and the politics of early Victorian science.

Built in 1769 as a private observatory for King George III, Kew Observatory was taken over in 1842 by the British Association for the Advancement of Science (BAAS). It was then quickly transformed into what some claimed to be a 'physical observatory' of the sort proposed by John Herschel - an observatory that gathered data in a wide range of physical sciences, including geomagnetism and meteorology, rather than just astronomy. Yet this article argues that the institution which emerged in the 1840s was different in many ways from that envisaged by Herschel. It uses a chronological framework to show how, at every stage, the geophysicist and Royal Artillery officer Edward Sabine manipulated the project towards his own agenda: an independent observatory through which he could control the geomagnetic and meteorological research, including the ongoing 'Magnetic Crusade'. The political machinations surrounding Kew Observatory, within the Royal Society and the BAAS, may help to illuminate the complex politics of science in early Victorian Britain, particularly the role of 'scientific servicemen' such as Sabine. Both the diversity of activities at Kew and the complexity of the observatory's origins make its study important in the context of the growing field of the 'observatory sciences'.

Right-sided superior vena cava draining into the left atrium in a patient with persistent left-sided superior vena cava emptying into the right atrium diagnosed by echocardiography.

We present a patient with an isolated right-sided superior vena cava draining into the left atrium with a persistent left-sided superior vena cava emptying into the right atrium. During an agitated saline injection into the patient's right upper extremity intravenous line, the patient suffered an acute transient ischemic attack. To our knowledge, this is the only reported case of this rare anomaly incidentally uncovered during an echocardiogram with saline contrast study.

Closure of patent foramen ovale versus medical therapy after cryptogenic stroke.

BACKGROUND: Whether closure of a patent foramen ovale is effective in the prevention of recurrent ischemic stroke in patients who have had a cryptogenic stroke is unknown. We conducted a trial to evaluate whether closure is superior to medical therapy alone in preventing recurrent ischemic stroke or early death in patients 18 to 60 years of age. METHODS: In this prospective, multicenter, randomized, event-driven trial, we randomly assigned patients, in a 1:1 ratio, to medical therapy alone or closure of the patent foramen ovale. The primary results of the trial were analyzed when the target of 25 primary end-point events had been observed and adjudicated. RESULTS: We enrolled 980 patients (mean age, 45.9 years) at 69 sites. The medical-therapy group received one or more antiplatelet medications (74.8%) or warfarin (25.2%). Treatment exposure between the two groups was unequal (1375 patient-years in the closure group vs. 1184 patient-years in the medical-therapy group, P=0.009) owing to a higher dropout rate in the medical-therapy group. In the intention-to-treat cohort, 9 patients in the closure group and 16 in the medical-therapy group had a recurrence of stroke (hazard ratio with closure, 0.49; 95% confidence interval [CI], 0.22 to 1.11; P=0.08). The between-group difference in the rate of recurrent stroke was significant in the prespecified per-protocol cohort (6 events in the closure group vs. 14 events in the medical-therapy group; hazard ratio, 0.37; 95% CI, 0.14 to 0.96; P=0.03) and in the as-treated cohort (5 events vs. 16 events; hazard ratio, 0.27; 95% CI, 0.10 to 0.75; P=0.007). Serious adverse events occurred in 23.0% of the patients in the closure group and in 21.6% in the medical-therapy group (P=0.65). Procedure-related or device-related serious adverse events occurred in 21 of 499 patients in the closure group (4.2%), but the rate of atrial fibrillation or device thrombus was not increased. CONCLUSIONS: In the primary intention-to-treat analysis, there was no significant benefit associated with closure of a patent foramen ovale in adults who had had a cryptogenic ischemic stroke. However, closure was superior to medical therapy alone in the prespecified per-protocol and as-treated analyses, with a low rate of associated risks. (Funded by St. Jude Medical; RESPECT ClinicalTrials.gov number, NCT00465270.).

Sex proportion of offspring and exposure to radiation in male invasive cardiologists.

High radiation exposure among male radiologists has been reported to result in a significantly higher proportion of female offspring. This study examined whether work-related radiation exposure was associated with a higher propensity for female offspring among male interventional cardiologists. On behalf of the interventional committee of the Society for Cardiovascular Angiography and Interventions, an Internet-based questionnaire was sent to the society's 2063 members. The 402 male respondents had a total of 518 biological offspring; 48.6% of them were female. Among the 172 high-volume male diagnostic operators (those who performed >300 cases annually), there were 218 biological offspring, of whom 46.8% were female. Among the 59 high-volume male interventional operators, there were 70 biological offspring, of whom 45.7% were female. P values were nonsignificant for all three groups. In conclusion, work-related radiation exposure of male invasive and interventional cardiologists was not associated with a statistically significant preponderance of female offspring.

Development and application of a GIS-based sediment budget model.

Accelerated erosion and increased sediment yields resulting from changes in land use are a critical environmental problem. Resource managers and decision makers need spatially explicit tools to help them predict the changes in sediment production and delivery due to unpaved roads and other types of land disturbance. This is a particularly important issue in much of the Caribbean because of the rapid pace of development and potential damage to nearshore coral reef communities. The specific objectives of this study were to: (1) develop a GIS-based sediment budget model; (2) use the model to evaluate the effects of unpaved roads on sediment delivery rates in three watersheds on St. John in the US Virgin Islands; and (3) compare the predicted sediment yields to pre-existing data. The St. John Erosion Model (STJ-EROS) is an ArcInfo-based program that uses empirical sediment production functions and delivery ratios to quantify watershed-scale sediment yields. The program consists of six input routines and five routines to calculate sediment production and delivery. The input routines have interfaces that allow the user to adjust the key variables that control sediment production and delivery. The other five routines use pre-set erosion rate constants, user-defined variables, and values from nine data layers to calculate watershed-scale sediment yields from unpaved road travelways, road cutslopes, streambanks, treethrow, and undisturbed hillslopes. STJ-EROS was applied to three basins on St. John with varying levels of development. Predicted sediment yields under natural conditions ranged from 2 to 7Mgkm(-2)yr(-1), while yield rates for current conditions ranged from 8 to 46Mgkm(-2)yr(-1). Unpaved roads are estimated to be increasing sediment delivery rates by 3-6 times for Lameshur Bay, 5-9 times for Fish Bay, and 4-8 times for Cinnamon Bay. Predicted basin-scale sediment yields for both undisturbed and current conditions are within the range of measured sediment yields and bay sedimentation rates. The structure and user interfaces in STJ-EROS mean that the model can be readily adapted to other areas and used to assess the impact of unpaved roads and other land uses sediment production and delivery.

Antirestenotic effects of a locally delivered caspase inhibitor in a balloon injury model.

BACKGROUND: The precise role of arterial barotrauma-mediated apoptosis in causing restenosis is unclear. The purpose of this study was to determine if a link exists between angioplasty-mediated medial smooth muscle cell apoptosis and subsequent neointimal hyperplasia. METHODS AND RESULTS: Bilateral iliac artery angioplasty was performed in 25 male New Zealand White rabbits. Simultaneous with balloon injury, each artery was treated locally with either the caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp(Ome)-fluoromethylketone (ZVAD-fmk) or control. In the acute cohort that was survived to 4 hours (n=10, 7 high dose and 3 low dose), an apoptotic index was calculated using the terminal deoxynucleotidyl TUNEL method. In the intermediate cohort that was survived to 2 weeks (n=5), luminal reendothelialization was measured via CD-31 staining. In the chronic cohort that was survived to 4 weeks (n=10), neointimal area was measured. In the acute cohort, there was a 40% reduction in the apoptotic index with high-dose ZVAD-fmk (P=0.008) and a 33% reduction with low-dose ZVAD-fmk (P=0.08). At 2 weeks, there was no significant difference in the degree of luminal reendothelialization. However, at 4 weeks, there was a 33% (0.33+/-0.23 versus 0.22+/-0.20 mm2) (P<0.005) reduction in neointimal area in ZVAD-fmk-treated arteries. CONCLUSIONS: The local delivery of ZVAD-fmk during balloon injury inhibits smooth muscle cell apoptosis. This corresponds to a significant reduction in neointimal proliferation seen at 4 weeks without a significant change in the degree of reendothelialization at 2 weeks.