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The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.
The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance.
MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.
Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3.
MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.
Background: Chlorhexidine bathing reduces bacterial skin colonization and prevents infections in specific patient populations. As chlorhexidine use becomes more widespread, concerns about bacterial tolerance to chlorhexidine have increased; however, testing for chlorhexidine minimum inhibitory concentrations (MICs) is challenging. We adapted a broth microdilution (BMD) method to determine whether chlorhexidine MICs changed over time among 4 important healthcare-associated pathogens. Methods: Antibiotic-resistant bacterial isolates (Staphylococcus aureus from 2005 to 2019 and Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae complex from 2011 to 2019) were collected through Emerging Infections Program surveillance in 2 sites (Georgia and Tennessee) or through public health reporting in 1 site (Orange County, California). A convenience sample of isolates were collected from facilities with varying amounts of chlorhexidine use. We performed BMD testing using laboratory-developed panels with chlorhexidine digluconate concentrations ranging from 0.125 to 64 μg/mL. After successfully establishing reproducibility with quality control organisms, 3 laboratories performed MIC testing. For each organism, epidemiological cutoff values (ECVs) were established using ECOFFinder. Results: Among 538 isolates tested (129 S. aureus, 158 E. coli, 142 K. pneumoniae, and 109 E. cloacae complex), S. aureus, E. coli, K. pneumoniae, and E. cloacae complex ECVs were 8, 4, 64, and 64 µg/mL, respectively (Table 1). Moreover, 14 isolates had an MIC above the ECV (12 E. coli and 2 E. cloacae complex). The MIC50 of each species is reported over time (Table 2). Conclusions: Using an adapted BMD method, we found that chlorhexidine MICs did not increase over time among a limited sample of S. aureus, E. coli, K. pneumoniae, and E. cloacae complex isolates. Although these results are reassuring, continued surveillance for elevated chlorhexidine MICs in isolates from patients with well-characterized chlorhexidine exposure is needed as chlorhexidine use increases.
There is increasing evidence that domestic violence (DV) is an important risk factor for suicidal behaviour. The level of risk and its contribution to the overall burden of suicidal behaviour among men and women has not been quantified in South Asia. We carried out a large case-control study to examine the association between DV and self-poisoning in Sri Lanka.
Cases (N = 291) were patients aged ⩾18 years, admitted to a tertiary hospital in Kandy Sri Lanka for self-poisoning. Sex and age frequency matched controls were recruited from the hospital's outpatient department (N = 490) and local population (N = 450). Exposure to DV was collected through the Humiliation, Afraid, Rape, Kick questionnaire. Multivariable logistic regression models were conducted to estimate the association between DV and self-poisoning, and population attributable fractions were calculated.
Exposure to at least one type of DV within the previous 12 months was strongly associated with self-poisoning for women [adjusted OR (AOR) 4.08, 95% CI 1.60–4.78] and men (AOR 2.52, 95% CI 1.51–4.21), compared to those reporting no abuse. Among women, the association was strongest for physical violence (AOR 14.07, 95% CI 5.87–33.72), whereas among men, emotional abuse showed the highest risk (AOR 2.75, 95% CI 1.57–4.82). PAF% for exposure to at least one type of DV was 38% (95% CI 32–43) in women and 22% (95% CI 14–29) in men.
Multi-sectoral interventions to address DV including enhanced identification in health care settings, community-based strategies, and integration of DV support and psychological services may substantially reduce suicidal behaviour in Sri Lanka.
NeuroStar transcranial magnetic stimulation (TMS) is an effective acute treatment for patients with major depressive disorder (MDD). In order to further understand use of the NeuroStar in a clinical setting, Neuronetics has established a patient treatment and outcomes registry to collect and analyze utilization information on patients receiving treatment with the NeuroStar.
Individual NeuroStar providers are invited to participate in the registry and agree to provide their de-identified patient treatment data. The NeuroStar has an integrated electronic data management system (TrakStar) which allows for the data collection to be automated. The data collected for the registry include Demographic Elements (age, gender), Treatment Parameters, and Clinical Ratings. Clinical assessments are: Clinician Global Impression - Severity of Illness (CGI-S) and thePatient Health Questionnaire 9-item (PHQ-9). De-identified patient data is uploaded to Registry server; an independent statistical service then creates final data reports.
Over 500 patients have entered the NeuroStar Outcomes Registry since Sept 2016. Mean patient age: 48.0 (SD±16.0); 64% Female. Baseline PHQ-9, mean 18.8 (SD±5.0.) Response/Remission Rate, PHQ-9: 61%/33% CGI-S: 78%/59%.
For the initial 500 patients in the Outcomes Registry, approximately 2/3 patients achieve respond and 1/3 patients achieve remission with an acute course of NeuroStar. These treatment outcomes consistent with NeuroStar open-label study data (Carpenter, 2012). The TrakStar data management system makes large scale data collection feasible. The NeuroStarOutcomes Registry is ongoing, and expected to reach 6000 outpatients from more than 47 clinical sites in 36 months.
Scales are widely used in psychiatric assessments following self-harm. Robust evidence for their diagnostic use is lacking.
To evaluate the performance of risk scales (Manchester Self-Harm Rule, ReACT Self-Harm Rule, SAD PERSONS scale, Modified SAD PERSONS scale, Barratt Impulsiveness Scale); and patient and clinician estimates of risk in identifying patients who repeat self-harm within 6 months.
A multisite prospective cohort study was conducted of adults aged 18 years and over referred to liaison psychiatry services following self-harm. Scale a priori cut-offs were evaluated using diagnostic accuracy statistics. The area under the curve (AUC) was used to determine optimal cut-offs and compare global accuracy.
In total, 483 episodes of self-harm were included in the study. The episode-based 6-month repetition rate was 30% (n = 145). Sensitivity ranged from 1% (95% CI 0–5) for the SAD PERSONS scale, to 97% (95% CI 93–99) for the Manchester Self-Harm Rule. Positive predictive values ranged from 13% (95% CI 2–47) for the Modified SAD PERSONS Scale to 47% (95% CI 41–53) for the clinician assessment of risk. The AUC ranged from 0.55 (95% CI 0.50–0.61) for the SAD PERSONS scale to 0.74 (95% CI 0.69–0.79) for the clinician global scale. The remaining scales performed significantly worse than clinician and patient estimates of risk (P < 0.001).
Risk scales following self-harm have limited clinical utility and may waste valuable resources. Most scales performed no better than clinician or patient ratings of risk. Some performed considerably worse. Positive predictive values were modest. In line with national guidelines, risk scales should not be used to determine patient management or predict self-harm.
The Patient Reported Outcomes Burdens and Experiences (PROBE) questionnaire was developed with direct patient involvement in questionnaire design, conduct and analysis using patient-centered outcomes to assess health status in patients with hemophilia (PWH). Phase 1 confirmed robustness of the methodology and feasibility. Phase 2a investigated individual test-retest reliability. Phase 2b will explore population level reproducibility.
PWH and non-PWH individuals who attended a hemophilia-related workshop were asked to complete the PROBE questionnaire 3 times (paper-based survey on 2 consecutive days and then a web-based version). Test-retest reliability was analyzed using the percentage agreement and Kappa statistic. Kappa coefficient interpretation .81-1.00 almost perfect, .61- .80 substantial; .41- .60 moderate; .21 -.40 fair; .00 -.20, slight; and < .00 poor agreement.
Sixty-three participants from twenty-one countries were enrolled with a median age of 50 (range 14–76) years. Of these, thirty (47.6 percent) were PWH or carriers, thirty-three (52.5 percent) were participants with no known bleeding disorders. On general health domain, Kappa coefficients ranged from .69 to .92, indicating substantial to almost perfect agreement, for all items. Reliability of the web-based questionnaire showed moderate to substantial agreement for all except one item. For the hemophilia-related domain, Kappa coefficients ranged from .5-1.0. Of these, five of eleven items were in perfect agreement (Kappa = 1.0). Reliability of web-based questionnaire items were in substantial to almost perfect agreement. For overall health related quality of life, the EuroQol five dimensions questionnaire (EQ-5D) had Kappa coefficients of .62 to .92. Intraclass correlation coefficient of visual analog scale (VAS) was .90 (95 percent Confidence Interval, CI; .83-.94). Test-retest reliability was comparable between hemophilia patients and participants with no known bleed.
Phase 2a demonstrated individual test-retest reliability and suggests PROBE is a reliable tool to assess Patient Reported Outcomes in PWH. The Web-based questionnaire has an acceptable agreement with the standard paper-based version in all domains. PROBE Phase 2b, to demonstrate reproducibility at the population level, is on-going. To date, 1,039 participants have been recruited from 10 countries.
We present an overview of the survey for radio emission from active stars that has been in progress for the last six years using the observatories at Fleurs, Molonglo, Parkes and Tidbinbilla. The role of complementary optical observations at the Anglo-Australian Observatory, Mount Burnett, Mount Stromlo and Siding Spring Observatories and Mount Tamborine are also outlined. We describe the different types of star that have been included in our survey and discuss some of the problems in making the radio observations.
We apply n- and p-type polycrystalline silicon (poly-Si) films on tunneling SiOx to form passivated contacts to n-type Si wafers. The resulting induced emitter and n+/n back surface field junctions of high carrier selectivity and low contact resistivity enable high efficiency Si solar cells. This work addresses the materials science of their performance governed by the properties of the individual layers (poly-Si, tunneling oxide) and more importantly, by the process history of the cell as a whole. Tunneling SiOx layers (<2 nm) are grown thermally or chemically, followed by a plasma enhanced chemical vapor deposition growth of p+ or n+ doped a-Si:H. The latter is thermally crystallized into poly-Si, resulting in grain nucleation and growth as well as dopant diffusion within the poly-Si and penetration through the tunneling oxide into the Si base wafer. The cell process is designed to improve the passivation of both oxide interfaces and tunneling transport through the oxide. A novel passivation technique involves coating of the passivated contact and whole cell with atomic layer deposited Al2O3 and activating them at 400 °C. The resulting excellent passivation persists after subsequent chemical removal of the Al2O3. The preceding cell process steps must be carefully tailored to avoid structural and morphological defects, as well as to maintain or improve passivation, and carrier selective transport. Furthermore, passivated contact metallization presents significant challenges, often resulting in passivation loss. Suggested remedies include improved Si cell wafer surface morphology (without micropyramids) and postdeposited a-Si:H capping layers over the poly-Si.
Key pathophysiology of sickle cell anaemia includes compensatory erythropoiesis, vascular injury and chronic inflammation, which divert amino acids from tissue deposition for growth/weight gain and muscle formation. We hypothesised that sickle mice maintained on an isoenergetic diet with a high percentage of energy derived from protein (35 %), as opposed to a standard diet with 20 % of energy derived from protein, would improve body composition, bone mass and grip strength. Male Berkeley transgenic sickle mice (S; n 8–12) were fed either 20 % (S20) or 35 % (S35) diets for 3 months. Grip strength (BIOSEB meter) and body composition (dual-energy X-ray absorptiometry scan) were measured. After 3 months, control mice had the highest bone mineral density (BMD) and bone mineral content (BMC) (P < 0·005). S35 mice had the largest increase in grip strength. A two-way ANOVA of change in grip strength (P = 0·043) attributed this difference to genotype (P = 0·025) and a trend in type of diet (P = 0·067). l-Arginine (l-Arg) supplementation of the 20 % diet was explored, as a possible mechanism for improvement obtained with the 35 % diet. Townes transgenic sickle mice (TS; n 6–9) received 0·8, 1·6, 3·2 or 6·4 % l-Arg based on the same protocol and outcome measures used for the S mice. TS mice fed 1·6 % l-Arg for 3 months (TS1.6) had the highest weight gain, BMD, BMC and lean body mass compared with other groups. TS3.2 mice showed significantly more improvement in grip strength than TS0·8 and TS1.6 mice (P < 0·05). In conclusion, the high-protein diet improved body composition and grip strength. Outcomes observed with TS1.6 and TS3.2 mice, respectively, confirm the hypothesis and reveal l-Arg as part of the mechanism.
Interventions that prevent healthcare-associated infection should lead to fewer deaths and shorter hospital stays. Cleaning hands (with soap or alcohol) is an effective way to prevent the transmission of organisms, but rates of compliance with hand hygiene are sometimes disappointingly low. The National Hand Hygiene Initiative in Australia aimed to improve hand hygiene compliance among healthcare workers, with the goal of reducing rates of healthcare-associated infection.
We examined whether the introduction of the National Hand Hygiene Initiative was associated with a change in infection rates. Monthly infection rates for healthcare-associated Staphylococcus aureus bloodstream infections were examined in 38 Australian hospitals across 6 states. We used Poisson regression and examined 12 possible patterns of change, with the best fitting pattern chosen using the Akaike information criterion. Monthly bed-days were included to control for increased hospital use over time.
The National Hand Hygiene Initiative was associated with a reduction in infection rates in 4 of the 6 states studied. Two states showed an immediate reduction in rates of 17% and 28%, 2 states showed a linear decrease in rates of 8% and 11% per year, and 2 showed no change in infection rates.
The intervention was associated with reduced infection rates in most states. The failure in 2 states may have been because those states already had effective initiatives before the national initiative’s introduction or because infection rates were already low and could not be further reduced.
Although what drives the abundance and habitat selection of ungulates is a long-standing question, coherent datasets investigating the influences of rainfall, competition and fire on ungulates are unusual. Over 4 y we carried out extensive monthly road transects in Ithala Game Reserve, South Africa, to determine the demographics and habitat occupancy of the region's prevalent grazer (wildebeest) and mixed-feeder (impala). Habitat occupancy was determined using a GIS-based approach. We obtained 8742 sighting records, encompassing 8400 wildebeest and 10071 impala. Annual rainfall did not significantly correlate with population sizes of either species. Fecundity of wildebeest, but not of impala, showed a significant positive relationship with rainfall specifically over the perinatal period (November–December), whilst no significant relationships were found for either species between fecundity and rainfall over the previous year, 2 y, rut (February–April) or height of the dry season (June–August). Impala unexpectedly favoured browse habitats to grassland year round, probably consequent on competition for grass with wildebeest. Dry-season grass flushes attracted both wildebeest and impala. The study emphasized how rainfall, competition and fire regimes may affect differently grazers compared with mixed-feeders.
Vertically aligned graphene was grown by plasma-enhanced chemical vapor deposition using methane feedstock. Optical emission spectroscopy (OES) was used to monitor the plasma species, and Raman spectroscopy was used for characterizing the properties of as-grown vertically aligned graphene. OES-derived information on plasma species, such as C, C2, CH, and H, are correlated with the properties of the vertically aligned graphene. Graphene grown at 250 W and 15 sccm exhibited the lowest amount of defects. Although OES peak intensities occurred at the highest power and lowest flow conditions, the OES peak ratios of plasma species had a greater dependence on flow rate and exhibited a saddle point in the atomic C/H ratio corresponding to optimal growth involving the lowest amount of overall defects. Plasma diagnostics provides a valuable approach to optimize growth characteristics and material properties.
When crude oil or petroleum products are released during a marine oil spill, organisms living in the water or feeding at the surface are the first to be affected. Oil on water or mixed into the water column may injure aquatic species of all types. Understanding the potential for injury to organisms from exposure to oil requires fully studying physical and chemical effects and quickly communicating the results. The risks to the public from the consumption of fish or other species normally harvested from the water can also be serious. A comprehensive water-assessment program provides quantitative data to address multiple concerns.
The Exxon Valdez oil spill was, until recently, the most comprehensively sampled oil spill in history and remains the most exhaustively studied oil spill. In fact, the thoroughness of the data – and the disappearance of most oil slicks and sheens by the end of the summer of 1989 – enabled all commercial fisheries to be reopened in 1990, much earlier than had been anticipated. Techniques and protocols established during the Exxon Valdez spill have been used in subsequent spills, most notably in the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.
Following a marine oil spill, it is important to know where the oil goes, how it changes chemically, how long the oil persists in various environmental compartments such as water or sediments, and what biological resources are affected. As an oil spill progresses over time, the behavior of the oil and the impacted areas and levels of risk to people and biological resources such as fish and wildlife change. Scientific studies provide the most benefit to cleanup efforts and the protection of people and biological resources in the area when they are coordinated and focused on the most pressing questions based on the phase of the oil spill. Over several decades, previous marine oil spills have shown a consistent pattern; understanding this pattern can help predict where the oil will go, how it changes chemically, where it will persist, and what living things are likely to be affected. Similarly, this predictability, coupled with specific observations at each spill, can help to provide a framework for designing and conducting studies that can address key questions at critical junctures in the evolution of the spill.
Water and air are the first environmental media affected during the early phase of any marine spill. Animal and plant life (or “biological resources”) can be affected immediately – as can humans involved in spill cleanup. The initial exposures to the chemicals in petroleum and the resulting effects can be acute, but short-lived. This is because once the spilled oil is no longer moving on or in the water, concentrations of harmful chemicals decrease rapidly owing to dilution, dispersion, and degradation (collectively known as “weathering”). Likewise, the evaporation of the volatile hydrocarbon components of fuels or crude oil immediately following a spill first increases, then decreases. By contrast, the effects on shoreline biological resources from oil that reaches land may persist. The last area potentially to be affected is bottom sediments, where oil can be transported before or after it reaches land (Chapter 4).
Most oil tanker accidents occur near land. So when a marine oil spill occurs, it is usually not long before the spilled oil reaches shorelines. The shoreline is where the potential for harm to the environment and biological resources is the greatest, and where media attention and public concerns usually focus. Therefore, it is essential to determine the distribution, amount, composition, and fate of spilled oil on shorelines. This information forms the foundation for management decisions about cleanup during the early phases of the spill, assessments of long-term exposure and injury to biological resources, and long-term restoration strategies after the initial cleanup.
In this chapter, we consider the fate of shoreline oil following the Exxon Valdez oil spill, beginning with oil coming ashore in Prince William Sound (PWS) in 1989. This chapter picks up where Chapter 3 left off, describing where the oil was deposited, why some locations were oiled more than others, and how oil disappeared over time and why, in a few isolated locations, it persisted.
Coastal shorelines teem with life. The intersection of the land with the sea, combined with tidal fluctuations and coastal currents, creates an array of habitats that supports an amazing diversity of plants and animals – limpets, starfish, anemones, crabs, rockweed, eelgrass, snails, tubeworms, and the like – that live on the surface and in the sediments of the intertidal zone. When floating oil from a marine oil spill strikes a shoreline, the potential effects on these organisms (the shoreline biota) may be severe. Even species that are not directly affected by spill may suffer its effects if the shoreline prey on which they feed are diminished. Understanding how a spill affects the shoreline biota is therefore important to assessing the potential effects on the broader shoreline and coastal ecosystems.
During the Exxon Valdez spill, oil first spread over shorelines in Prince William Sound (PWS) and later extended outside of PWS to the Kenai Peninsula, Kodiak Island, and Alaska Peninsula (see Map 1, p. v). The effects of the spill and the need to respond rapidly were of enormous concern, particularly within PWS, where oil quantities and potential toxicity were greatest. In this chapter, we discuss three major programs undertaken to assess the effects of the Exxon Valdez oil spill on shoreline biota in PWS, including studies to determine the effects of intensive cleanup efforts.