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The COVID-19 pandemic has created a high demand on personal protective equipment, including disposable N95 masks. Given the need for mask reuse, we tested the feasibility of vaporized hydrogen peroxide (VHP), ultraviolet light (UV), and ethanol decontamination strategies on N95 mask integrity and the ability to remove the infectious potential of SARS-CoV-2.
Disposable N95 masks, including medical grade (1860, 1870+) and industrial grade (8511) masks, were treated by vaporized hydrogen peroxide (VHP), ultraviolet light (UV), and ethanol decontamination. Mask degradation was tested using a quantitative respirator fit testing. Pooled clinical samples of SARS-CoV-2 were applied to mask samples, treated and and then either sent immediately for real-time reverse transcriptase–polymerase chain reaction (RT-PCR) or incubated with Vero E6 cells to assess for viracidal effect.
Both ethanol and UV decontamination showed functional degradation to different degrees while VHP treatment showed no significant change after 2 treatments.We also report a single SARS-CoV-2 virucidal experiment using Vero E6 cell infection in which only ethanol treatment eliminated detectable SARS-CoV-2 RNA.
We hope our data will guide further research for evidenced-based decisions for disposable N95 mask reuse and help protect caregivers from SARS-CoV-2 and other pathogens.
Transporting patients with communicable diseases is common in critical care transport operations. At Ornge, Ontario's critical care transport provider, 13.7% of patients required contact, droplet, or airborne precautions during transport in 2019–2020. Ensuring that staff are protected while transporting patients with communicable diseases must remain a prime directive for medical transport administrators and operators. Success in safety requires a robust system of hazard identification and adherence to generally accepted methods of hazard control. This commentary will discuss some of the administrative and engineering controls, as well as the personal protective equipment (PPE) strategies deployed at Ornge.
Populations of native North American parasitoids attacking Agrilus Curtis (Coleoptera: Buprestidae) species have recently been considered as part of an augmentative biological control programme in an attempt to manage emerald ash borer, Agrilus planipennis Fairmaire, a destructive wood-boring beetle discovered in North America in 2002. We evaluate trapping methods to detect and monitor populations of two important native larval parasitoids, Phasgonophora sulcata Westwood (Hymenoptera: Chalcididae) and Atanycolus Förster (Hymenoptera: Braconidae) species, attacking emerald ash borer in its introduced range. We found that purple prism traps captured more P. sulcata than green prism traps, yellow pan traps, and log samples and thus were considered better for detecting and monitoring P. sulcata populations. Trap type did not affect the number of captures of Atanycolus species. Surprisingly, baiting prism traps with a green leaf volatile or manuka oil did not significantly increase captures of P. sulcata or Atanycolus species. Based on these results, unbaited purple prism traps would be optimal for sampling these native emerald ash borer parasitoids in long-term management programmes.
The US National Institutes of Health (NIH) established the Clinical and Translational Science Award (CTSA) program in response to the challenges of translating biomedical and behavioral interventions from discovery to real-world use. To address the challenge of translating evidence-based interventions (EBIs) into practice, the field of implementation science has emerged as a distinct discipline. With the distinction between EBI effectiveness research and implementation research comes differences in study design and methodology, shifting focus from clinical outcomes to the systems that support adoption and delivery of EBIs with fidelity.
Implementation research designs share many of the foundational elements and assumptions of efficacy/effectiveness research. Designs and methods that are currently applied in implementation research include experimental, quasi-experimental, observational, hybrid effectiveness–implementation, simulation modeling, and configurational comparative methods.
Examples of specific research designs and methods illustrate their use in implementation science. We propose that the CTSA program takes advantage of the momentum of the field's capacity building in three ways: 1) integrate state-of-the-science implementation methods and designs into its existing body of research; 2) position itself at the forefront of advancing the science of implementation science by collaborating with other NIH institutes that share the goal of advancing implementation science; and 3) provide adequate training in implementation science.
As implementation methodologies mature, both implementation science and the CTSA program would greatly benefit from cross-fertilizing expertise and shared infrastructures that aim to advance healthcare in the USA and around the world.
Propagating inhomogeneous electromagnetic waves called surface plasmon polaritons (SPPs) can be excited by free-space beams on corrugated conducting surfaces at resonance angles determined by corrugation period, permittivity, and optical frequency. SPPs are coupled to and co-propagate with surface charge displacements. Complete electrical isolation of individual conducting corrugations prevents the charge displacement necessary to sustain an SPP, such that excitation resonances of traveling SPPs are absent. However, SPPs can be excited via electric induction if a smooth conducting surface exists below and nearby the isolated conducting corrugations. The dependence of SPP excitation resonances on that separation is experimentally investigated here at long-wave infrared wavelengths. We find that excitation resonances for traveling SPPs broaden and disappear as the dielectric’s physical thickness is increased beyond ∼1% of the free-space wavelength. The resonance line width increases with refractive index and optical thickness of the dielectric.
Building on prior work using Tom Dishion's Family Check-Up, the current article examined intervention effects on dysregulated irritability in early childhood. Dysregulated irritability, defined as reactive and intense response to frustration, and prolonged angry mood, is an ideal marker of neurodevelopmental vulnerability to later psychopathology because it is a transdiagnostic indicator of decrements in self-regulation that are measurable in the first years of life that have lifelong implications for health and disease. This study is perhaps the first randomized trial to examine the direct effects of an evidence- and family-based intervention, the Family Check-Up (FCU), on irritability in early childhood and the effects of reductions in irritability on later risk of child internalizing and externalizing symptomatology. Data from the geographically and sociodemographically diverse multisite Early Steps randomized prevention trial were used. Path modeling revealed intervention effects on irritability at age 4, which predicted lower externalizing and internalizing symptoms at age 10.5. Results indicate that family-based programs initiated in early childhood can reduce early childhood irritability and later risk for psychopathology. This holds promise for earlier identification and prevention approaches that target transdiagnostic pathways. Implications for future basic and prevention research are discussed.
The wheat bZip transcription factor TaABF1 mediates both abscisic acid (ABA)-induced and ABA-suppressed gene expression. As levels of TaABF1 protein do not change in response to ABA, and TaABF1 is in a phosphorylated state in vivo, we investigated whether TaABF1 could be regulated at the post-translational level. In bombarded aleurone cells, a TaABF1 protein carrying phosphomimetic mutations (serine to aspartate) at four sites (S36D, S37D, S113D, S115D) was three to five times more potent than wild-type TaABF1 in activating HVA1, an ABA-responsive gene. The phosphomimetic mutations also increased the ability of TaABF1 to downregulate the ABA-suppressed gene Amy32b. These findings strongly suggest that phosphorylation at these sites increases the transcriptional regulatory activity of TaABF1. In contrast to the activation observed by the quadruple serine to aspartate mutation, a single S113D mutation completely eliminated the ability of TaABF1 to upregulate HVA1 or downregulate Amy32b. Thus phosphorylation of TaABF1 can either stimulate or inhibit the activity of TaABF1 in regulating downstream genes, depending on the site and pattern of phosphorylation. Mutation of S318 and S322 (in the bZIP domain) eliminated the ability of TaABF1 to activate HVA1, but had no effect on the ability of TaABF1 to downregulate Amy32b, suggesting that TaABF1 represses Amy32b expression through a mechanism other than direct DNA binding. An important step towards understanding how ABA and gibberellin (GA) signals are integrated through TaABF1 phosphorylation to regulate downstream gene expression is to clarify the effects of those hormones on the expression of specific genes. In contrast to some other ABA-induced genes, we found that HVA1 induction by ABA or TaABF1 is not inhibited by GA.
Metal–insulator–metal (MIM) resonant absorbers comprise a conducting ground plane, a dielectric of thickness t, and thin separated metal top-surface structures of dimension l. The fundamental resonance wavelength is predicted by an analytic standing-wave model based on t, l, and the dielectric refractive index spectrum. For the dielectrics SiO2, AlN, and TiO2, values for l of a few microns give fundamental resonances in the 8-12 μm long-wave infrared (LWIR) wavelength region. Agreement with theory is better for t/l exceeding 0.1. Harmonics at shorter wavelengths were already known, but we show that there are additional resonances in the far-infrared 20 - 50 μm wavelength range in MIM structures designed to have LWIR fundamental resonances. These new resonances are consistent with the model if far-IR dispersion features in the index spectrum are considered. LWIR fundamental absorptions are experimentally shown to be optimized for a ratio t/l of 0.1 to 0.3 for SiO2- and AlN-based MIM absorbers, respectively, with TiO2-based MIM optimized at an intermediate ratio.
Metal–insulator–metal (MIM) resonant absorbers comprise a conducting ground plane, a thin dielectric, and thin separated metal top-surface structures. The dielectric SiO2 strongly absorbs near 9 µm wavelength and has correspondingly strong long-wave-infrared (LWIR) dispersion for the refractive index. This dispersion results in multiple absorption resonances spanning the LWIR, which can enhance broad-band sensitivity for LWIR bolometers. Similar considerations apply to silicon nitride Si3N4. TiO2 and AlN have comparatively low dispersion and give simple single LWIR resonances. These dispersion-dependent features for infrared MIM devices are demonstrated by experiment, electrodynamic simulation, and an analytic model based on standing waves.
Vanadium Oxide has application to infrared bolometers due to high temperature coefficient of resistivity (TCR). It has attracted interest for switchable plasmonic devices due to its metal to insulator transition near room temperature. We report here the properties of vanadium oxide deposited by an aqueous spray process. The films have a ropy surface morphology with ∼70 nm surface roughness. The polycrystalline phase depends on annealing conditions. The films have TCR of ∼2%/deg, which compares well with sputtered films. Only weak evidence is found for an insulator-metal phase transition in these films.
Ternary lead chalcogenides, such as PbSxSe1-x, offer the possibility of room-temperature infrared detection with engineered cut-off wavelengths within the important 3-5 micron mid-wave infrared (MWIR) wavelength range. We present growth and characterization of aqueous spray-deposited thin films of PbSSe. Complexing agents in the aqueous medium suppress unwanted homogeneous reactions so that growth occurs only by the heterogeneous reaction on the hydrophilic substrate. The strongly-adherent films are smooth with a mirror-like finish. The films comprise densely packed grains with tens of nm dimensions and a total film thickness of ∼400-500 nm. Measured optical constants reveal absorption out to at least 4.5 μm wavelength and a ∼0.3 eV bandgap intermediate between those of PbS and PbSe. The semiconducting films are p-type with resistivity ∼1 and 85 Ohm-cm at 300 and 80 K, respectively. Sharp x-ray diffraction peaks identify the films as Clausthalite-Galena solid-state solution with a lattice constant that indicates an even mixture of PbS and PbSe. The photoconductive response is observed at both nitrogen and room temperature up to at least 2 kHz chopping frequency.
Self-assembled TiO2 films deposited by aqueous-spray deposition were investigated to evaluate morphology, crystalline phase, and infrared optical constants. The Anatase nano-crystalline film had ∼10 nm characteristic surface roughness sparsely punctuated by defects of not more than 200 nm amplitude. The film is highly transparent throughout the visible to wavelengths of 12 μm. The indirect band gap was determined to be 3.2 eV. Important for long-wave infrared applications is that dispersion in this region is weak compared with the more commonly used dielectric SiO2 for planar structures. An example application to a metal-insulator-metal resonant absorber is presented. The low-cost, large-area, atmospheric-pressure, chemical spray deposition method allows conformal fabrication on flexible substrates for long-wave infrared photonics.
Over the past 30 years, the number of US doctoral anthropology graduates has increased by about 70%, but there has not been a corresponding increase in the availability of new faculty positions. Consequently, doctoral degree-holding archaeologists face more competition than ever before when applying for faculty positions. Here we examine where US and Canadian anthropological archaeology faculty originate and where they ultimately end up teaching. Using data derived from the 2014–2015 AnthroGuide, we rank doctoral programs whose graduates in archaeology have been most successful in the academic job market; identify long-term and ongoing trends in doctoral programs; and discuss gender division in academic archaeology in the US and Canada. We conclude that success in obtaining a faculty position upon graduation is predicated in large part on where one attends graduate school.
Older adults are a potentially medically vulnerable population with increased mortality rates during and after disasters. To evaluate the impact of a natural disaster on this population, we performed a temporal and geospatial analysis of emergency department (ED) use by adults aged 65 years and older in New York City (NYC) following Hurricane Sandy’s landfall.
We used an all-payer claims database to analyze demographics, insurance status, geographic distribution, and health conditions for post-disaster ED visits among older adults. We compared ED patterns of use in the weeks before and after Hurricane Sandy throughout NYC and the most afflicted evacuation zones.
We found significant increases in ED utilization by older adults (and disproportionately higher in those aged ≥85 years) in the 3 weeks after Hurricane Sandy, especially in NYC evacuation zone one. Primary diagnoses with notable increases included dialysis, electrolyte disorders, and prescription refills. Secondary diagnoses highlighted homelessness and care access issues.
Older adults display heightened risk for worse health outcomes with increased ED visits after a disaster. Our findings suggest the need for dedicated resources and planning for older adults following a natural disaster by ensuring access to medical facilities, prescriptions, dialysis, and safe housing and by optimizing health care delivery needs to reduce the burden of chronic disease. (Disaster Med Public Health Preparedness. 2018;12:184–193)
Palladium germanide thin films were investigated for infrared plasmonic applications. Palladium thin films were deposited onto amorphous germanium thin films and subsequently annealed at a range of temperatures. X-ray diffraction was used to identify stoichiometry, and Scanning Electron Micrographs, along with Energy Dispersive Spectroscopy (EDS) was used to characterize composition and film quality. Resistivity was also measured for analysis. Complex permittivity spectra were measured from 0.3 to 15 µm using IR ellipsometry. From this, surface plasmon polariton (SPP) characteristics such as propagation length and mode confinement were calculated and used to determine appropriate spectral windows for plasmonic applications with respect to film characteristics. Films were evaluated for use with on-chip plasmonic components.
Addition of wavelength selective absorbers on microbolometers tends to increase their thermal mass and slow their infrared response times. Making the bolometric material an integral part of the absorber and minimizing layer thicknesses is one possible way to maintain high detector speeds. Here, we study experimentally the effect on permittivity of adding a layer of semiconducting VOx between two layers of SiO2. Additionally, we investigate theoretically the effect on resonance wavelength of thinning the metal in metal-insulator-metal plasmonic resonant absorbers.
Suicide is a leading cause of death for young people. Children living in sub-Saharan Africa, where HIV rates are disproportionately high, may be at increased risk.
To identify predictors, including HIV status, of suicidal ideation and behaviour in Rwandan children aged 10–17.
Matched case–control study of 683 HIV-positive, HIV-affected (seronegative children with an HIV-positive caregiver), and unaffected children and their caregivers.
Over 20% of HIV-positive and affected children engaged in suicidal behaviour in the previous 6 months, compared with 13% of unaffected children. Children were at increased risk if they met criteria for depression, were at high-risk for conduct disorder, reported poor parenting or had caregivers with mental health problems.
Policies and programmes that address mental health concerns and support positive parenting may prevent suicidal ideation and behaviour in children at increased risk related to HIV.
The emergence and persistence of conduct problems (CPs) during early childhood is a robust predictor of behavior problems in school and of future maladaptation. In this study we examined the reciprocal influences between observed coercive interactions between children and caregivers, oppositional and aggressive behavior, and growth in parent report of early childhood (ages 2–5) and school-age CPs (ages 7.5 and 8.5). Participants were drawn from the Early Steps multisite randomized prevention trial that includes an ethnically diverse sample of male and female children and their families (N = 731). A parallel-process growth model combining latent trajectory and cross-lagged approaches revealed the amplifying effect of observed coercive caregiver–child interactions on children's noncompliance, whereas child oppositional and aggressive behaviors did not consistently predict increased coercion. The slope and initial levels of child oppositional and aggressive behaviors and the stability of caregiver–child coercion were predictive of teacher-reported oppositional behavior at school age. Families assigned to the Family Check-Up condition had significantly steeper declines in child oppositional and aggressive behavior and moderate reductions in oppositional behavior in school and in coercion at age 3. Results were not moderated by child gender, race/ethnicity, or assignment to the intervention condition. The implications of these findings are discussed with respect to understanding the early development of CPs and to designing optimal strategies for reducing problem behavior in early childhood with families most in need.