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Despite lessons learned from the recent Ebola epidemic, attempts to survey and determine non-health care worker, industry-specific needs to address highly infectious diseases have been minimal. The aircraft rescue and fire fighting (ARFF) industry is often overlooked in highly infectious disease training and education, even though it is critical to their field due to elevated occupational exposure risk during their operations.
Supervisors perceived Frontline respondents to be more willing and comfortable to encounter potential highly infectious disease scenarios than the Frontline indicated. More than one-third of respondents incorrectly marked transmission routes of viral hemorrhagic fevers. There were discrepancies in self-reports on the existence of highly infectious disease orientation and skills demonstration, employee resources, and personal protective equipment policies, with a range of 7.5%-24.0% more Supervisors than Frontline respondents marking activities as conducted.
There are deficits in highly infectious disease knowledge, skills, and abilities among ARFF members that must be addressed to enhance member safety, health, and well-being. (Disaster Med Public Health Preparedness. 2018;12:675-679)
Janus spheres, micron-sized silica spheres half-coated with platinum, move rectilinearly away from the platinum side in aqueous hydrogen peroxide. Upon self-assembling, these colloidal particles can form dimers with different conformations that exhibit both rectilinear and rotational modes of motion depending upon the relative orientation of each Janus sphere. At the micron length-scale, stochastic rotational Brownian dynamics is of the order of deterministic dynamics, and their coupling results in effective diffusion, in addition to passive translational diffusion. For dimers with rotary motion, the dynamic coupling leads to spiral trajectories for an ensemble average of the displacement vector.
We present subarcsecond observations at 2.7 and 1.4 mm of a sample of massive young stellar objects made with the BIMA millimetre array. For most sources the continuum emission on the smallest scales at 2.7 mm is dominated by free-free emission from the stellar wind or jet. Strong emission at 1.4 mm shows the presence of significant dust associated with Cep A and GL 490 but our resolution is not sufficient to resolve any structure. The 2.7-mm emission from GL 490 is resolved but it is not clear whether we are seeing a single circumstellar disk or a secondary companion, although near-infrared data support the disk hypothesis. Estimates of the dust mass yield values of ∼1–4 M⊙ within radii of 150 to 1000 AU.
To describe current Ebola treatment center (ETC) locations, their capacity to care for Ebola virus disease patients, and infection control infrastructure features.
A 19-question survey was distributed electronically in April 2015. Responses were collected via email by June 2015 and analyzed in an electronic spreadsheet.
The survey was sent to and completed by site representatives of each ETC.
The survey was sent to all 55 ETCs; 47 (85%) responded.
Of the 47 responding ETCs, there are 84 isolation beds available for adults and 91 for children; of these pediatric beds, 35 (38%) are in children’s hospitals. In total, the simultaneous capacity of the 47 reporting ETCs is 121 beds. On the basis of the current US census, there are 0.38 beds per million population. Most ETCs have negative pressure isolation rooms, anterooms, and a process for category A waste sterilization, although only 11 facilities (23%) have the capability to sterilize infectious waste on site.
Facilities developed ETCs on the basis of Centers for Disease Control and Prevention guidance, but specific capabilities are not mandated at this present time. Owing to the complex and costly nature of Ebola virus disease treatment and variability in capabilities from facility to facility, in conjunction with the lack of regulations, nationwide capacity in specialized facilities is limited. Further assessments should determine whether ETCs can adapt to safely manage other highly infectious disease threats.
Infect. Control Hosp. Epidemiol. 2016;37(3):313–318
Different front-of-pack (FOP) labelling systems have been developed in Europe by industry and organisations concerned with health promotion. A study (n 2068) was performed to establish the extent to which inclusion of the most prevalent FOP systems – guideline daily amounts (GDA), traffic lights (TL), GDA+TL hybrid (HYB) and health logos (HL) – impact consumer perceptions of healthiness over and above the provision of a FOP basic label (BL) containing numerical nutritional information alone. The design included within- and between-subjects factors. The within-subjects factors were: food (pizzas, yogurts and biscuits), healthiness of the food (high health, medium health and low health) and the repeated measurements under BL and test FOP label conditions. The between-subjects factors were: the system (GDA, TL, GDA+TL hybrid, HL), portion size (typical portion size and a 50 % reduction of a typical portion) and country (the UK, Germany, Poland and Turkey). Although the FOP systems tested did result in small improvements for objective understanding under some conditions, there was little difference between the provision of an FOP label containing basic numerical nutritional information alone or between the various systems. Thus, any structured and legible presentation of key nutrient and energy information on the FOP label is sufficient to enable consumers to detect a healthier alternative within a food category when provided with foods that have distinctly different levels of healthiness. Future research should focus on developing greater understanding of the psychological and contextual factors that impact motivation and the opportunity to use the various FOP systems in real-world shopping settings.
Deep borehole disposal (or DBD) is now seen as a viable alternative to the (comparatively shallow) geologically repository concept for disposal of high level waste and spent nuclear fuel. Based on existing oil and geothermal well technologies, we report details of investigations into cementitious grouts as sealing/support matrices (SSMs) for waste disposal scenarios in the DBD process where temperatures at the waste package surface do not exceed ∼190ºC. Grouts based on Class G oil well cements, partially replaced with silica flour, are being developed, and the use of retarding admixtures is being investigated experimentally. Sodium gluconate appears to provide sufficient retardation and setting characteristics to be considered for this application and also provides an increase in grout fluidity. The quantity of sodium gluconate required in the grout to ensure fluidity for 4 hours at 90, 120 and 140°C is 0.05, 0.25 and 0.25 % by weight of cement respectively. A phosphonate admixture only appears to provide desirable retardation properties at 90°C. The presence of either retarder does not affect the composition of the hardened cement paste over 14 days curing and the phases formed are durable under conditions of high temperature and pressure.
Geological disposal of HLW and spent nuclear fuel (SNF) in very deep boreholes is a concept whose time has come. The alternative – disposal in a mined, engineered repository is beset with difficulties not least of which are the constraints placed upon the engineered barriers by the high thermal loading. The deep borehole concept offers a potentially safer, faster and more cost-effective solution. Despite this, international interest has been slow to materialize, largely due to perceived problems with retrievability and uncertainty about the ability to drill accurate vertical holes with diameters greater than 0.5 m to a depth of 4-5 km. The closure of Yucca Mountain and the subsequent recommendations of the Blue Ribbon Commission have lead to a renewed interest in deep borehole disposal (DBD) and the US DoE has commissioned Sandia National Labs, working with industrial and academic partners (including the University of Sheffield), to undertake a program of R&D leading to a demonstration borehole being drilled somewhere in the continental USA by 2016.
In this paper, we focus on some of the key safety and engineering features of DBD including methods of sealing the boreholes, sealing and support matrices for the waste packages. Numerical modeling has, and continues to play, a significant role in expanding and validating the DBD concept. We report on progress in the use of modeling in the above contexts, paying particular attention to constraints on the engineering materials resulting from high heat loading.
Minimizing healthcare worker exposure to airborne infectious pathogens is an important infection control practice. This study utilized mathematical modeling to evaluate the trajectories and subsequent concentrations of particles following a simulated release in a patient care room.
Biocontainment unit patient care room at a university-affiliated tertiary care medical center.
. Quantitative mathematical modeling of airflow in a patient care room was achieved using a computational fluid dynamics software package. Models were created on the basis of a release of particles from various locations in the room. Computerized particle trajectories were presented in time-lapse fashion over a blueprint of the room. A series of smoke tests were conducted to visually validate the model.
Most particles released from the head of the bed initially rose to the ceiling and then spread across the ceiling and throughout the room. The highest particle concentrations were observed at the head of the bed nearest to the air return vent, and the lowest concentrations were observed at the foot of the bed.
Mathematical modeling provides clinically relevant data on the potential exposure risk in patient care rooms and is applicable in multiple healthcare delivery settings. The information obtained through mathematical modeling could potentially serve as an infection control modality to enhance the protection of healthcare workers.
The heat outputs of higher burn up spent fuels (SF) create problems for disposal in mined repositories, including needs for reduced container loadings and extended pre-disposal cooling. An alternative that is less temperature sensitive is deep borehole disposal (DBD) which offers safety, cost, security and other potential benefits and could be implemented relatively quickly using currently available deep-drilling technology. We have modified our previously proposed version of DBD to be more appropriate for higher burn-up fuels by using smaller (0.36 m diameter) stainless steel containers, a smaller (0.56 m diameter) borehole, and different support matrices. We present the results of new heat-flow modelling for DBD of UO2 and MOX SF with burn ups of 55 and 65 GWd/t showing how temperatures evolve, especially on the outer surface of the containers. Consequences for the performance of the support matrices and the disposal concept are discussed. The thermal modelling indicates DBD is a viable option for higher burn-up SF and could be a practical disposal route for many combinations of fuel types, burn ups, ages and container loadings. Further, the results suggest that DBD of complete fuel assemblies, a desirable option, would be feasible and require much shorter pre-disposal cooling than necessary for disposal in mined repositories.
In 2010, an outbreak of cyclosporiasis affected passengers and crew on two successive voyages of a cruise ship that departed from and returned to Fremantle, Australia. There were 73 laboratory-confirmed and 241 suspected cases of Cyclospora infection reported in passengers and crew from the combined cruises. A case-control study performed in crew members found that illness was associated with eating items of fresh produce served onboard the ship, but the study was unable conclusively to identify the responsible food(s). It is likely that one or more of the fresh produce items taken onboard at a south-east Asian port during the first cruise was contaminated. If fresh produce supplied to cruise ships is sourced from countries or regions where Cyclospora is endemic, robust standards of food production and hygiene should be applied to the supply chain.
The objective of this study was to quantify the effectiveness of selected surgical masks in arresting vegetative cells and endospores in an experimental model that simulated contagious patients.
Five commercially available surgical masks were tested for their ability to arrest infectious agents. Surgical masks were placed over the nose and mouth of mannequin head forms (Simulaids adult model Brad CPR torso). The mannequins were retrofitted with a nebulizer attached to an automated breathing simulator calibrated to a tidal volume of 500 mL/breath and a breathing rate of 20 breaths/min, for a minute respiratory volume of 10 L/min. Aerosols of endospores or vegetative cells were generated with a modified microbiological research establishment-type 6-jet collision nebulizer, while air samples were taken with all-glass impinger (AGI-30) samplers downstream of the point source. All experiments were conducted in a horizontal bioaerosol chamber.
Mean arrestance of bioaerosols by the surgical masks ranged from 48% to 68% when the masks were challenged with endospores and from 66% to 76% when they were challenged with vegetative cells. When the arrestance of endospores was evaluated, statistical differences were observed between some pairs, though not all, of the models evaluated. There were no statistically significant differences in arrestance observed between models of surgical masks challenged with vegetative cells.
The arrestance of airborne vegetative cells and endospores by surgical masks worn by simulated contagious patients supports surgical mask use as one of the recommended cough etiquette interventions to limit the transmission of airborne infectious agents.
This study evaluated the efficacy of gaseous chlorine dioxide (ClO2) for extermination of bedbugs (Cimex lectularius and Citnex hemipterus).
Bedbugs have received attention because of recent outbreaks. Bedbug eradication is difficult and often requires a time-consuming multifaceted approach.
Laboratory and hospital room.
Bedbugs were exposed to concentrations of ClO2 of 362, 724, and 1,086 parts per million (ppm) in an exposure chamber. Bedbug mortality was then evaluated. The ability of ClO2 to penetrate various spaces in a hospital room was evaluated using Bacillus atropheus as a surrogate organism.
Concentrations of 1,086 and 724 ppm of ClO2 yielded 100% bedbug mortality assessed immediately after exposure. Live young were not observed for any eggs exposed to ClO2 gas. ClO2 at a concentration of 362 ppm for 1,029 parts per million hours (ppm-hours) achieved 100% mortality 6 hours after exposure. A ClO2 concentration of 362 ppm for 519 ppm-hours had 100% mortality 18 hours after exposure. Up to a 6-log reduction in B. atropheus spores was achieved using similar concentrations of ClO2 in a hospital room, indicating that the concentrations needed to kill bedbugs can be achieved throughout a hospital room.
ClO2 is effective at killing bedbugs in the laboratory, and similar concentrations of ClO2 gas can be achieved in a hospital room. ClO2 can be removed from the room without residuals.
Higher burn-up (> 50 GWd/t) spent nuclear fuels (SNF) present problems for long-term management and disposal in mined repositories, principally because of their higher heat output. Here we present results from heat flow modeling of an alternative scheme for disposing of SNF - deep borehole disposal (DBD). We focus on how temperatures on the outer surface of the containers evolve, affect the melting and re-solidification of the high density support matrix (HDSM) and their consequences for the feasibility of this disposal concept. We conclude that not only is DBD a viable option for higher burn-up SNF, but it could be a practical disposal route for a range of combinations of SNF ages and number of fuel pins per container.