Predicting wildfire particulate matter and hypothetical re-emission of radiological Cs-137 contamination incidents.

Radiological release incidents can potentially contaminate widespread areas with radioactive materials and decontamination efforts are typically focused on populated areas, which means radionuclides may be left in forested areas for long periods of time. Large wildfires in contaminated forested areas have the potential to reintroduce these radionuclides into the atmosphere and cause exposure to first responders and downwind communities. One important radionuclide contaminant released from radiological incidents is radiocesium (137Cs) due to high yields and its long half-life of 30.2 years. An Eulerian 3D photochemical transport model was used to estimate potential ambient impacts of 137Cs re-emission due to wildfire following hypothetical radiological release scenarios. The Community Multiscale Air Quality (CMAQ) model did well at predicting levels and periods of increased PM2.5 carbon due to wildfire smoke at routine surface monitors in California during the summer of 2016. The model also did well at capturing the extent of the surface mixing layer compared to aerosol lidar measurements. Emissions from a large hypothetical wildfire were introduced into the wildland-urban interface (WUI) impacted by a hypothetical radiological release event. While ambient concentrations tended to be highest near the fire, the highest population committed effective dose equivalent by inhalation to an adult from 137Cs over an hour was downwind where wind flows moved smoke to high population areas. Seasonal variations in meteorology (wind flows) can result in differential population impacts even in the same metropolitan area. Modeled post-incident ambient levels of 137Cs both near these wildfires and further downwind in nearby urban areas were well below levels that would necessitate population evacuation or warrant other protective action recommendations such as shelter-in-place. These results suggest that 1) the modeling system captures local to regional scale transport and levels of PM2.5 from wildfire and 2) first responders and downwind population would not be expected to be at elevated risk from the initial inhalathion exposure of 137Cs re-emission.

Telehealth in Mental Health Nursing Education: Health Care Simulation With Remote Presence Technology.

The feasibility of integrating remote presence technology within a simulation scenario for psychiatric-mental health nursing (PMHN) students to develop telehealth competencies was evaluated. A wireless, audiovisual robot from Double® Robotics, maneuverable by smartphone or tablet computer, was used to simulate the facilitation of students' patient assessment and treatment decisions from a distant location for 32 weeks (total hours of robotic simulation = 32). Qualitative data were collected to assess student and faculty satisfaction, as well as for feasibility evaluations. Overall, students participating in the telehealth-enabled simulations reported moderate (9 of 36 students) to strong (25 of 36 students) value for the use of telemedicine within the simulation in a 3-point Likert scale post-simulation survey. These results illustrate the feasibility of using a remote presence robot in an educational simulation environment. Remote presence in clinical simulations can contribute to workforce preparation to apply telehealth-enabled communication in PMHN settings. [Journal of Psychosocial Nursing and Mental Health Services, 57(7), 23-28.].

Cesium emissions from laboratory fires.

If a radiological incident such as a nuclear power plant accident, a radiological dispersal device, or detonation of an improvised nuclear device occurs, significant areas may be contaminated. Initial cleanup priorities would likely focus on populated areas, leaving the forested areas to pass several seasons where the overhead canopy materials would fall to the forest floor. In the event of a wildfire in a radionuclide-contaminated forest, some radionuclides would be emitted in the air while the rest would remain in the ash. This paper reports on a laboratory simulation study that examines the partitioning of cesium-133 (a nonradioactive isotope of cesium) between airborne particulate matter and residual nonentrained ash when pine needles and peat are doped with cesium. Only 1-2.5% of the doped cesium in pine needles was emitted as particulate matter, and most of the cesium was concentrated in the particulate fraction greater than 10 µm in aerodynamic diameter. For peat fires, virtually all of the cesium remained in the ash. The results from this study will be used for modeling efforts to assess potential exposure risks to firefighters and the surrounding public. Implications: There is a potential for emissions of radionuclides such as cesium-137 from a wildfire over a radionuclide-contaminated forest. This paper reports on a laboratory simulation study of a wildfire with two types of biomass doped with nonradioactive cesium. This simulation suggests that only 1-2.5% of the cesium in the biomass will be emitted from the wildfire, while the rest will reside in the residual ash. In this study, pine needles were the only contributor to the air emissions of cesium; duff was not a source of cesium emissions. In this study, cesium emitted from the simulated wildfire was concentrated in the particle sizes larger than 10 µm.

Revision stapedectomy with bone cement: are results comparable to those of standard techniques?

OBJECTIVE: To examine hearing results in revision stapedectomy using hydroxyapatite bone cement for incus necrosis. STUDY DESIGN: Retrospective case series. SETTING: Tertiary care academic medical center. PATIENTS: Eligible patients underwent revision stapedectomy for otosclerosis using hydroxyapatite bone cement to reconstruct incus necrosis between March 2007 and August 2013. Patients were excluded for insufficient audiometric data or an operative indication other than otosclerosis. INTERVENTION: Revision stapedectomy performed with standard stapes piston prostheses using hydroxyapatite bone cement to stabilize the prosthesis. MAIN OUTCOME MEASURE: Air-bone gap (ABG), air-conduction and bone conduction pure-tone audiometry thresholds, and speech discrimination scores (SDSs) were obtained preoperatively and postoperatively. The preoperative result closest to the date of surgery was compared with the postoperative result farthest from the date of surgery. RESULTS: Twenty-seven patients (aged 32-83 yr) met criteria and were included in the study. Average duration of follow-up was 7 months (range, 1-39 mo). Postoperative closure of the ABG to within 10 dB was achieved in 77.8% of cases. Closure to within 20 dB was achieved in 96.3%. The average postoperative ABG was 8.1 dB (range, 0-24 dB). The average SDS change was +7.4% (-12% to +92%). There were no cases of significant postoperative sensorineural hearing loss by bone conduction pure-tone audiometry. CONCLUSION: Use of hydroxyapatite cement for treatment of incus necrosis in revision stapedectomy provides excellent hearing outcomes and is a reasonable alternative to total ossicular reconstruction prosthesis or malleovestibular prosthesis techniques.

Foreign body impaction as presentation of eosinophilic esophagitis.

Esophageal foreign body is a frequent pediatric presentation, and eosinophilic esophagitis (EoE) is an important underlying disease. To determine characteristics common in the presentation of esophageal foreign body indicative of underlying EoE and reach a recommendation for the appropriate scenario in which to obtain esophageal mucosal biopsy, 312 pediatric esophageal foreign bodies requiring operative removal were reviewed. Patients older than 18 years or with a known history of esophageal surgery or pathology were excluded. Eligibility criteria were met in 271 cases. Twenty-seven patients were biopsied, and 18 were diagnosed with EoE. The following factors were identified in the EoE population: food impaction (89%), older age (average 12.2 years), male sex (78%), atopic disease (61%), previous esophageal foreign body or frequent dysphagia (83%), and endoscopic abnormalities (100%). These factors are all associated with an underlying diagnosis of EoE, and patients meeting these criteria should be strongly considered for intraoperative esophageal mucosal biopsy.

Meckelin 3 is necessary for photoreceptor outer segment development in rat Meckel syndrome.

Ciliopathies lead to multiorgan pathologies that include renal cysts, deafness, obesity and retinal degeneration. Retinal photoreceptors have connecting cilia joining the inner and outer segment that are responsible for transport of molecules to develop and maintain the outer segment process. The present study evaluated meckelin (MKS3) expression during outer segment genesis and determined the consequences of mutant meckelin on photoreceptor development and survival in Wistar polycystic kidney disease Wpk/Wpk rat using immunohistochemistry, analysis of cell death and electron microscopy. MKS3 was ubiquitously expressed throughout the retina at postnatal day 10 (P10) and P21. However, in the mature retina, MKS3 expression was restricted to photoreceptors and the retinal ganglion cell layer. At P10, both the wild type and homozygous Wpk mutant retina had all retinal cell types. In contrast, by P21, cells expressing rod- and cone-specific markers were fewer in number and expression of opsins appeared to be abnormally localized to the cell body. Cell death analyses were consistent with the disappearance of photoreceptor-specific markers and showed that the cells were undergoing caspase-dependent cell death. By electron microscopy, P10 photoreceptors showed rudimentary outer segments with an axoneme, but did not develop outer segment discs that were clearly present in the wild type counterpart. At p21 the mutant outer segments appeared much the same as the P10 mutant outer segments with only a short axoneme, while the wild-type controls had developed outer segments with many well-organized discs. We conclude that MKS3 is not important for formation of connecting cilium and rudimentary outer segments, but is critical for the maturation of outer segment processes.

In ovo eye electroporation.

Electroporation has been used successfully to introduce macromolecules such as DNA into the chick embryo for at least 15 years. Purified plasmid DNA is microinjected into embryo and then a series of low voltage electrical pulses are applied to the embryo which allows naked DNA to enter cells. Following entrance into the cytoplasm, the DNA is transported to the nucleus where it is transiently expressed. This powerful technique is useful for studies involving overexpression, misexpression, and knockdown of genes of interest at a variety of developmental timepoints.