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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 VHP, 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 then either sent immediately for real-time reverse transcriptase–polymerase chain reaction (RT-PCR) or incubated with Vero E6 cells to assess for virucidal effect.
Both ethanol and UV decontamination showed functional degradation to different degrees while VHP treatment showed no significant change after two 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.
The typical onset of schizophrenia coincides with the maturational peak in cognition; however, for a significant proportion of patients the onset is before age 18 and after age 30 years. While cognitive deficits are considered core features of schizophrenia, few studies have directly examined the impact of age of illness onset on cognition.
The aim of the study was to examine if the effects of age on cognition differ between healthy controls (HCs) and patients with schizophrenia at illness onset. We examined 156 first-episode antipsychotic-naïve patients across a wide age span (12–43 years), and 161 age- and sex-matched HCs. Diagnoses were made according to ICD-10 criteria. Cognition was assessed using the Brief Assessment of Cognition in Schizophrenia (BACS), and IQ was estimated using subtests from the Wechsler adult- or child-intelligence scales. Multivariate analysis of covariance (MANCOVA) was used to examine linear and quadratic effects of age on cognitive scores and interactions by group, including sex and parental socioeconomic status as covariates.
There was a significant overall effect of age on BACS and IQ (p < 0.001). Significant group-by-age interactions for verbal memory (for age-squared, p = 0.009), and digit sequencing (for age, p = 0.01; age-squared, p < 0.001), indicated differential age-related trajectories between patients and HCs.
Cognitive functions showing protracted maturation into adulthood, such as verbal memory and verbal working memory, may be particularly impaired in both early- and late-schizophrenia onset. Our findings indicate a potential interaction between the timing of neurodevelopmental maturation and a possible premature age effect in late-onset schizophrenia.
In January of 2010, North Carolina (NC) USA implemented state-wide Trauma Triage Destination Plans (TTDPs) to provide standardized guidelines for Emergency Medical Services (EMS) decision making. No study exists to evaluate whether triage behavior has changed for geriatric trauma patients.
The impact of the NC TTDPs was investigated on EMS triage of geriatric trauma patients meeting physiologic criteria of serious injury, primarily based on whether these patients were transported to a trauma center.
This is a retrospective cohort study of geriatric trauma patients transported by EMS from March 1, 2009 through September 30, 2009 (pre-TTDP) and March 1, 2010 through September 30, 2010 (post-TTDP) meeting the following inclusion criteria: (1) age 50 years or older; (2) transported to a hospital by NC EMS; (3) experienced an injury; and (4) meeting one or more of the NC TTDP’s physiologic criteria for trauma (n = 5,345). Data were obtained from the Prehospital Medical Information System (PreMIS). Data collected included proportions of patients transported to a trauma center categorized by specific physiologic criteria, age category, and distance from a trauma center.
The proportion of patients transported to a trauma center pre-TTDP (24.4% [95% CI 22.7%-26.1%]; n = 604) was similar to the proportion post-TTDP (24.4% [95% CI 22.9%-26.0%]; n = 700). For patients meeting specific physiologic triage criteria, the proportions of patients transported to a trauma center were also similar pre- and post-TTDP: systolic blood pressure <90 mmHg (22.5% versus 23.5%); respiratory rate <10 or >29 (23.2% versus 22.6%); and Glascow Coma Scale (GCS) score <13 (26.0% versus 26.4%). Patients aged 80 years or older were less likely to be transported to a trauma center than younger patients in both the pre- and post-TTDP periods.
State-wide implementation of a TTDP had no discernible effect on the proportion of patients 50 years and older transported to a trauma center. Under-triage remained common and became increasingly prevalent among the oldest adults. Research to understand the uptake of guidelines and protocols into EMS practice is critical to improving care for older adults in the prehospital environment.
Experiments with a weakly damped monopile, either fixed or free to oscillate, exposed to irregular waves in deep water, obtain the wave-exciting moment and motion response. The nonlinearity and peak wavenumber cover the ranges:
is an estimate of the spectral wave slope,
the significant wave height,
the peak wavenumber and
the cylinder radius. The response and its statistics, expressed in terms of the exceedance probability, are discussed as a function of the resonance frequency,
in the range
times the spectral peak frequency,
. For small wave slope, long waves and
, the nonlinear response deviates only very little from its linear counterpart. However, the nonlinearity becomes important for increasing wave slope, wavenumber and resonance frequency ratio. The extreme response events are found in a region where the Keulegan–Carpenter number exceeds
, indicating the importance of possible flow separation effects. A similar region is also covered by a Froude number exceeding
, pointing to surface gravity wave effects at the scale of the cylinder diameter. Regarding contributions to the higher harmonic forces, different wave load mechanisms are identified, including: (i) wave-exciting inertia forces, a function of the fluid acceleration; (ii) wave slamming due to both non-breaking and breaking wave events; (iii) a secondary load cycle; and (iv) possible drag forces, a function of the fluid velocity. Also, history effects due to the inertia of the moving pile, contribute to the large response events. The ensemble means of the third, fourth and fifth harmonic wave-exciting force components extracted from the irregular wave results are compared to the third harmonic FNV (Faltinsen, Newman and Vinje) theory as well as other available experiments and calculations. The present irregular wave measurements generalize results obtained in deep water regular waves.
In 785 mother–child (50% male) pairs from a longitudinal epidemiological birth cohort, we investigated associations between inflammation-related epigenetic polygenic risk scores (i-ePGS), environmental exposures, cognitive function, and child and adolescent internalizing and externalizing problems. We examined prenatal and postnatal effects. For externalizing problems, one prenatal effect was found: i-ePGS at birth associated with higher externalizing problems (ages 7–15) indirectly through lower cognitive function (age 7). For internalizing problems, we identified two effects. For a prenatal effect, i-ePGS at birth associated with higher internalizing symptoms via continuity in i-ePGS at age 7. For a postnatal effect, higher postnatal adversity exposure (birth through age 7) associated with higher internalizing problems (ages 7–15) via higher i-ePGS (age 7). Hence, externalizing problems were related mainly to prenatal effects involving lower cognitive function, whereas internalizing problems appeared related to both prenatal and postnatal effects. The present study supports a link between i-ePGS and child and adolescent mental health.
Laboratory experiments with a bottom hinged surface-piercing cylinder, exposed to irregular deep water waves, are used to investigate high-frequency forcing. The focus is on the secondary load cycle, a strongly nonlinear phenomenon regarding the wave load on a vertical cylinder, first identified by Grue et al. (1993 Preprint Series. Mechanics and Applied Mathematics, pp. 1–30. University of Oslo, available at http://urn.nb.no/URN:NBN:no-52740; 1994 Ninth International Workshop on Water Waves and Floating Bodies (ed. M. Ohkusu), pp. 77–81, available at http://iwwwfb.org). For a total of 2166 single wave events, the force above
is the governing wave frequency) is used to identify and split the strongly nonlinear forces into two peaks: a high-frequency peak closely correlated in time with the wave crest when the total load is positive and a high-frequency peak defining the secondary load cycle which occurs close in time to the wave zero downcrossing when the total load is negative. The two peaks are studied by regression analysis as a function of either the Keulegan–Carpenter number (
) or the Froude number (
). Regarding the secondary load cycle, the best correlation is found with
. The speed of the travelling edge of the undisturbed wave approximates the fluid velocity. A threshold value separating between small and large forces is found for
–5, indicating effects of flow separation. Alternatively, the threshold occurs for
–0.4, indicating local wave effects at the scale of the cylinder diameter. The findings suggest that both effects are present and important.
Engabreen is an outlet glacier of the Svartisen Ice Cap located in Northern Norway. It is a unique glacier due to the Svartisen Subglacial Laboratory which allows direct access to the glacier bed. In this study, we combine both sub- and supraglacial observations with ice-flow modelling in order to investigate conditions at the bed of Engabreen both spatially and temporally. We use the full-Stokes model Elmer/Ice and satellite-based surface-velocity maps from 2010 and 2014 to infer patterns of basal friction. Direct measurements of basal sliding and deformation of lower layers of the ice are used to adjust the ice viscosity and provide essential input to the setup of our model and influence the interpretation of the results. We find a clear seasonal cycle in the subglacial conditions at the higher elevation region of the study area and discuss this in relation to the subglacial hydrological system. Our results also reveal an area with an overdeepening where basal friction is significantly lower than elsewhere on the glacier all year round. We attribute this to either water pooling at the base, or saturated sediments and increased strain heating at this location which softens the ice further.
This chapter adopts new theoretical insights from cognitive science and dynamic systems theory and employs the notion of “metaphoricity” to explore how metaphor in discourse can be understood more adequately. Relating the ecological turn in cognitive science to metaphor studies and insisting on a unified bio-social perspective, it argues that metaphoricity – if conceptualized within an ecological framework – can offer an alternative to viewing metaphor as primarily social or cognitive. In-depth analyses of two real-life examples analyze metaphoricity as the act of doing metaphor within an interpersonal ecology established by the ongoing and dynamic presence of other people, physical artifacts and sociocultural constraints. Rather than treated as a product of individual minds, metaphor is thus shown to emerge from the dynamics of human dialogue viewed as a complex living system. The chapter focuses especially on how metaphoricity works as a gradable, interactively negotiated phenomenon that is intertwined with affective behaviors and situational affordances.
Selected hydrides (TiH2, ZrH2), chlorides (VCl3, ScCl3) or oxides (V2O5) utilized as additives facilitating hydrogen release and uptake for magnesium hydride were investigated using mechano-chemical treatment and in-situ synchrotron radiation powder X-ray diffraction studies. The fastest hydrogen desorption and absorption kinetics for MgH2 was observed for a sample with 5 mol% V2O5 at 320 °C. Additional activation of the system (2 cycles, vacuum/p(H2) ~150 bar, 450 °C) leads to significant improvement of the kinetics even at lower temperatures, 270 °C. The observed prolific effect is achieved through the full reduction of vanadium oxides and formation of an efficient vanadium catalyst as nanoparticles and possibly interfacial effects in the MgO/Mg/MgH2/V system introduced during cycling hydrogen release and uptake in hydrogen/dynamic vacuum at 450 °C. Nanostructuring as well as hydrogen permeability via vanadium nanoparticles may improve kinetics and reduce the apparent activation energy for hydrogen release. Thus, the enhancement of hydrogen release/uptake in the MgH2 owe to “in situ” formation of vanadium nanoparticles by reduction of V2O5.
The paper presents millimeter-wave (mm-wave) signal sources using a hetero-integrated InP-on-BiCMOS semiconductor technology. Mm-wave signal sources feature fundamental frequency voltage-controlled oscillators (VCOs) in BiCMOS, which drive frequency multiplier–amplifier chains in transferred-substrate (TS) InP-DHBT technology, heterogeneously integrated on top of the BiCMOS wafer in a wafer-level bonding process. Both circuits are biased through a single set of bias pads and compact low-loss transitions from BiCMOS to InP circuits and vice versa have been developed, which allows seamless signal routing through both technologies exhibiting 0.5 dB insertion loss up to 200 GHz. One VCO operates at 82 GHz with a tuning range of 600 MHz and an output power of approximately 8 dBm. A frequency doubler combined with this VCO circuit delivers 0 dBm at 164 GHz and a frequency tripler with a similar VCO delivers −10 dBm at 246 GHz. Another hetero-integrated W-band doubler–amplifier circuit demonstrates 12.9 dBm saturated output power with 5.9 dB conversion gain at 96 GHz. A direct comparison of the TS InP-DHBT MMIC with either silicon or traditional AlN carrier substrates shows the favorable properties of the hetero-integrated process discussed here. The results demonstrate the feasibility of hetero-integrated circuits operating well above 100 GHz.
In this paper, the small- and large-signal modeling of InP heterojunction bipolar transistors (HBTs) in transferred substrate (TS) technology is investigated. The small-signal equivalent circuit parameters for TS-HBTs in two-terminal and three-terminal configurations are determined by employing a direct parameter extraction methodology dedicated to III–V based HBTs. It is shown that the modeling of measured S-parameters can be improved in the millimeter-wave frequency range by augmenting the small-signal model with a description of AC current crowding. The extracted elements of the small-signal model structure are employed as a starting point for the extraction of a large-signal model. The developed large-signal model for the TS-HBTs accurately predicts the DC over temperature and small-signal performance over bias as well as the large-signal performance at millimeter-wave frequencies.
Long-term care (LTC) patients are often sent to emergency departments (EDs) by ambulance. In this novel extended care paramedic (ECP) program, specially trained paramedics manage LTC patients on site. The objective of this pilot study was to describe the dispatch and disposition of LTC patients treated by ECPs and emergency paramedics.
Data were collected from consecutive calls to 15 participating LTC facilities for 3 months. Dispatch determinants, transport rates, and relapse rates were described for LTC patients attended by ECPs or emergency paramedics. ECP involvement in end-of-life care was identified.
Of 238 eligible calls, 140 (59%) were attended by an ECP and 98 (41%) by emergency paramedics. Although the top three determinants were the same in each group, the overall distribution of dispatch determinants and acuity differed. In the ECP cohort, 98 of 140 (70%) were treated and released, 33 of 140 (24%) had “facilitated transfer” arranged by an ECP, and 9 of 140 (6%) were immediately transported to the ED by ambulance. In the emergency paramedic cohort, 77 of 98 (79%) were immediately transported to the ED and 21 of 98 (21%) were not transported. In the ECP group, 6 of 98 (6%) patients not transported triggered a 911 call within 48 hours for a related clinical reason, although none of the patients not transported by emergency paramedics relapsed.
ECP involvement in LTC calls was found to reduce transports to the ED with a low rate of relapse. These pilot data generated hypotheses for future study, including determination of appropriate populations for ECP care and analysis of appropriate and safe nontransport.
LiBH4 and MgH2 both have high gravimetric and volumetric hydrogen storage densities. Unfortunately, their commercial application is prevented by high thermal stability and unfavorable thermodynamic properties. Combining the two hydrides leads to a new decomposition pathway with suitable enthalpy of reaction. However, the kinetics for hydrogen release remains an obstacle but can be improved by nanoconfinement in nano porous carbon materials. Here we report on nanoconfinement of 2LiBH4-MgH2 in Ni functionalized carbon aerogels. 11B MAS NMR reveals that the nanoconfined hydrides react reversibly with hydrogen whereas simultaneous differential scanning calorimetry and mass spectroscopy clearly show that nanoconfinement facilitates lower hydrogen release temperatures than ball milling. Furthermore, Ni functionalization of the nanoporous aerogel leads to even lower hydrogen release temperatures from nanoconfined 2LiBH4-MgH2.
Parasitism is believed to play an important role in maintaining species diversity, for instance by facilitating coexistence between competing host species. However, the possibility that environmental factors may govern the outcome of parasite-mediated competition has rarely been considered. The closely related amphipods Corophium volutator and Corophium arenarium both serve as second intermediate host for detrimental trematodes. Corophium volutator is the superior competitor of the two, but also suffers from higher mortality when exposed to infective trematode stages. Here, we report parasite-mediated competitive release of C. arenarium in an intertidal habitat, in part triggered by unusually high temperatures linked to the North Atlantic climate oscillation (NAO). The elevated temperatures accelerated the transmission of cercariae from sympatric first intermediate hosts (mud snails) to amphipods, causing a local collapse of the parasite-sensitive C. volutator population and concordant increase in the abundance of the competitively inferior C. arenarium.