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To investigate the touch-contact antimicrobial efficacy of novel cold spray surface coatings composed of copper and silver metals, regard to their rate of microbial elimination.
Antimicrobial time-kill assay.
An adapted time-kill assay was conducted to characterize the antimicrobial efficacy of the developed coatings. A simulated touch-contact pathogenic exposure to Gram-positive Staphylococcus aureus (ATCC 25923), Gram-negative Pseudomonas aeruginosa (ATCC 27853), and the yeast Candida albicans (ATCC 10231), as well as corresponding resistant strains of gentamicin-methicillin–resistant S. aureus (ATCC 33592), azlocillin-carbenicillin–resistant P. aeruginosa (DSM 46316), and a fluconazole-resistant C. albicans strain was undertaken. Linear regression modeling was used to deduce microbial reduction rates.
A >7 log reduction in microbial colony forming units was achieved within minutes on surfaces with cold spray coatings compared to a single log bacterial reduction on copper metal sheets within a 3 hour contact period. Copper-coated 3-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) achieved complete microbial elimination against all tested pathogens within a 15 minute exposure period. Similarly, a copper-on-copper coating achieved microbial elimination within 10 minutes and within 5 minutes with the addition of silver powder as a 5 wt% coating constituent.
In response to the global need for alternative solutions for infection control and prevention, these effective antimicrobial surface coatings were proposed. A longitudinal study is the next step toward technology integration.
Beginning upwards of half a millennium ago, European sojourners and their settler colonialist inheritors sought to acquire resource assets and eventually the land itself in Mi’kma’ki and the neighbouring homelands of the Wolastoqiyik and the Beothuk/Innu. This area, corresponding broadly in settler terms to Atlantic Canada, has seen a process of European expansion premised on appropriating the wealth, the resources and the bodies of non-European peoples. Historically, it was a process of unique antiquity, beginning with fisheries that predated the turn of the sixteenth century, and one in which Scots took an early and influential role. This volume, focusing primarily on eras following the onset of colonial settlement, offers a series of reappraisals of key developments not only in settler societies themselves but also in relation to African and Indigenous inhabitants. Insofar as the geographical frame of reference is Atlantic Canada, there is of course a sense in which the term is anachronistic. Only with the joining of Newfoundland (formally known from 2001 as Newfoundland and Labrador) to Canada in 1949 did Atlantic Canada become a regional designation for what had previously been distinguished respectively as the Dominion of Newfoundland and the Maritime provinces of the Dominion of Canada. Yet for analytical purposes, the term Atlantic Canada represents a justifiable shorthand for a portion of north-eastern North America that – despite variations in environment and in economic trajectories – shared important elements of both Indigenous and settlement histories.
In nineteenth- and twentieth-century historiographies, influenced by the ‘British and settler scholars’ clustered notably in the institutions described by Tamson Pietsch as ‘settler universities’, imperial expansion and colonial settlement were attributed central roles throughout the post-contact era. Yet Indigenous societies in this part of North America, which had evolved over a period of at least some ten thousand years, were not in reality so easily overshadowed. Contact with non-Indigenous commercial voyagers – English, French, Basque and others – from approximately 1500 onwards did make a difference, but not necessarily an unmanageable difference. Prior to that time, continuity and change were underwritten by factors operating within North America and, generally speaking, within north-eastern North America. Environmental change took forms ranging from the gradual but transformative process of warming that followed the last Ice Age to shorter-term variations that influenced transportation patterns and seasonal characteristics.
Behavioural therapy often involves self-monitoring techniques to increase awareness about mood and stressful events. In turn, emotional self-awareness is likely to decrease symptoms of depression. Self monitoring also has potential as an early intervention tool for young people, particularly when mobile phones are used as a medium. Previous qualitative research indicates that self-monitoring via mobile phones increase emotional self-awareness with five categories proposed: awareness, identification, communication, contextualisation and decision-making.
This RCT investigates the relationships between self-monitoring, emotional self-awareness and depression using an early intervention mobile phone self-monitoring tool with young people at risk of developing depression.
Young people (between 14 and 24 years of age) identified by their GP as being at risk of depression were recruited by GPs in rural and metropolitan Victoria and randomly assigned to either the intervention group (where they monitored their mood, stress and daily activities) or the comparison group (where the questions about mood and stress were excluded). Participants completed baseline and follow-up measures of depression as well as measures of emotional self-awareness.
Results will be presented on the effects of self-monitoring on emotional self-awareness, the effects of self-monitoring on depression, anxiety and stress and the relationship between emotional self-awareness and depression, anxiety and stress.
Emotional self-awareness as a mediator in the relationship between self-monitoring and depression will be discussed focusing on the relationships between
(ii) emotional self-awareness and
(iii) symptoms of depression, anxiety and stress.
Possible avenues for early intervention are suggested.
The mobiletype program is a cell/mobile phone mental health assessment and management tool designed specifically for young people aged 14–24 years to assist in detecting, managing, and treating of youth mental health problems. The mobiletype self-starts 4 times per day and the patient completes a brief survey of their current mood, stresses, coping, alcohol and cannabis use, exercise, sleeping and eating patterns. This data is transmitted in real- time to a website interface which collates it and produces individual reports for young people to share with their doctor.
118 young people identified with mild or more mental health symptoms were blindly randomly allocated at the individual level, to either the intervention group (mobiletype plus usual care) or the comparison group (abbreviated mobiletype plus usual care) according to CONSORT guidelines. Participants and doctors completed baseline and follow-up questionnaires measuring mental health, patient-doctor relationship, and pathways to care (i.e. referrals, medication, and testing). Participants were followed-up at 6 weeks and 6 months.
Results from fixed effects analyses of covariance examining the differences between the experimental and control groups on the main outcome measures, with the baseline values as the covariates will be presented. The extent to which the mobiletype program reduces mental health symptoms, enhances the patient-doctor relationship and assists patients in pathways to care will be explored in detail.
Mobile and new information and connected technologies have much to offer clinical care in terms of increased efficiencies in data collection, increased engagement of participants and overall enhanced care.
Nitrous oxide (N2O) misuse is widespread in the UK. Although it is well-known that it can cause devastating myeloneuropathy, psychiatric presentations are poorly described. There is little understanding of who it affects, how it presents, its mechanism of action and principles of treatment. We begin this article with a case study. We then review the literature to help psychiatrists understand this area and deal with this increasing problem, and make diagnosis and treatment recommendations. We describe a diagnostic pentad of weakness, numbness, paraesthesia, psychosis and cognitive impairment to alert clinicians to the need to urgently treat these patients. Nitrous oxide misuse is a pending neuropsychiatric emergency requiring urgent treatment with vitamin B12 to prevent potentially irreversible neurological and psychiatric symptoms.
In Canada, recreational use of cannabis was legalized in October 2018. This policy change along with recent publications evaluating the efficacy of cannabis for the medical treatment of epilepsy and media awareness about its use have increased the public interest about this agent. The Canadian League Against Epilepsy Medical Therapeutics Committee, along with a multidisciplinary group of experts and Canadian Epilepsy Alliance representatives, has developed a position statement about the use of medical cannabis for epilepsy. This article addresses the current Canadian legal framework, recent publications about its efficacy and safety profile, and our understanding of the clinical issues that should be considered when contemplating cannabis use for medical purposes.
Knowledge of the effects of burial depth and burial duration on seed viability and, consequently, seedbank persistence of Palmer amaranth (Amaranthus palmeri S. Watson) and waterhemp [Amaranthus tuberculatus (Moq.) J. D. Sauer] ecotypes can be used for the development of efficient weed management programs. This is of particular interest, given the great fecundity of both species and, consequently, their high seedbank replenishment potential. Seeds of both species collected from five different locations across the United States were investigated in seven states (sites) with different soil and climatic conditions. Seeds were placed at two depths (0 and 15 cm) for 3 yr. Each year, seeds were retrieved, and seed damage (shrunken, malformed, or broken) plus losses (deteriorated and futile germination) and viability were evaluated. Greater seed damage plus loss averaged across seed origin, burial depth, and year was recorded for lots tested at Illinois (51.3% and 51.8%) followed by Tennessee (40.5% and 45.1%) and Missouri (39.2% and 42%) for A. palmeri and A. tuberculatus, respectively. The site differences for seed persistence were probably due to higher volumetric water content at these sites. Rates of seed demise were directly proportional to burial depth (α=0.001), whereas the percentage of viable seeds recovered after 36 mo on the soil surface ranged from 4.1% to 4.3% compared with 5% to 5.3% at the 15-cm depth for A. palmeri and A. tuberculatus, respectively. Seed viability loss was greater in the seeds placed on the soil surface compared with the buried seeds. The greatest influences on seed viability were burial conditions and time and site-specific soil conditions, more so than geographical location. Thus, management of these weed species should focus on reducing seed shattering, enhancing seed removal from the soil surface, or adjusting tillage systems.
Despite 70 years of study, Dickinsonia remains one of the Ediacara biota’s most enigmatic taxa with both morphological characters and phylogenetic affinities still debated. A large population of relatively small Dickinsonia costata present on a semi-contiguous surface from the Crisp Gorge fossil locality in the Flinders Ranges (South Australia) provides an opportunity to investigate this taxon in its juvenile form. This population supports earlier findings that suggest D. costata’s early growth was isometric, based on the relationship between measured variables of length and width. The number of body units increases with length, but at a decreasing rate. A correlation between a previously described physical feature, present as a shrinkage rim partially surrounding some specimens and a novel, raised lip in some specimens, suggests that both features may have been the result of a physical contraction in response to the burial process, rather than due to a gradual loss of mass during early diagenesis. A marked protuberance in 15% of the population is also noted in limited specimens within the South Australian Museum collections and appears to be present only in juvenile D. costata. Both the abundance and narrow size range of this population support the notion that Dickinsonia was a hardy opportunist, capable of rapid establishment and growth on relatively immature textured organic-mat substrates.
Palmer amaranth (Amaranthus palmeri S. Watson) is a problematic weed encountered in U.S. cotton (Gossypium hirsutum L.) and soybean [Glycine max (L.) Merr.] production, with infestations spreading northward. This research investigated the influence of planting date (early, mid-, and late season) and population (AR, IN, MO, MS, NE, and TN) on A. palmeri growth and reproduction at two locations. All populations planted early or midseason at Throckmorton Purdue Agricultural Center (TPAC) and Arkansas Agriculture Research and Extension Center (AAREC) measured 196 and 141 cm or more, respectively. Amaranthus palmeri height did not exceed 168 and 134 cm when planted late season at TPAC and AAREC, respectively. Early season planted A. palmeri from NE grew to 50% of maximum height 8 to 13 d earlier than all other populations under TPAC conditions. In addition, the NE population planted early, mid-, and late season achieved 50% inflorescence emergence 5, 4, and 6 d earlier than all other populations, respectively. All populations established at TPAC produced fewer than 100,000 seeds plant−1. No population planted at TPAC and AAREC produced more than 740 and 1,520 g plant−1 of biomass at 17 and 19 wk after planting, respectively. Planting date influenced the distribution of male and female plants at TPAC, but not at AAREC. Amaranthus palmeri from IN and MS planted late season had male-to-female plant ratios of 1.3:1 and 1.7:1, respectively. Amaranthus palmeri introduced to TPAC from NE can produce up to 7,500 seeds plant−1 if emergence occurs in mid-July. An NE A. palmeri population exhibited biological characteristics allowing it to be highly competitive if introduced to TPAC due to a similar latitudinal range, but was least competitive when introduced to AAREC. Although A. palmeri originating from different locations can vary biologically, plants exhibited environmental plasticity and could complete their life cycle and contribute to spreading populations.
To identify predominant dietary patterns in four African populations and examine their association with obesity.
We used data from the Africa/Harvard School of Public Health Partnership for Cohort Research and Training (PaCT) pilot study established to investigate the feasibility of a multi-country longitudinal study of non-communicable chronic disease in sub-Saharan Africa. We applied principal component analysis to dietary intake data collected from an FFQ developed for PaCT to ascertain dietary patterns in Tanzania, South Africa, and peri-urban and rural Uganda. The sample consisted of 444 women and 294 men.
We identified two dietary patterns: the Mixed Diet pattern characterized by high intakes of unprocessed foods such as vegetables and fresh fish, but also cold cuts and refined grains; and the Processed Diet pattern characterized by high intakes of salad dressing, cold cuts and sweets. Women in the highest tertile of the Processed Diet pattern score were 3·00 times more likely to be overweight (95 % CI 1·66, 5·45; prevalence=74 %) and 4·24 times more likely to be obese (95 % CI 2·23, 8·05; prevalence=44 %) than women in this pattern’s lowest tertile (both P<0·0001; prevalence=47 and 14 %, respectively). We found similarly strong associations in men. There was no association between the Mixed Diet pattern and overweight or obesity.
We identified two major dietary patterns in several African populations, a Mixed Diet pattern and a Processed Diet pattern. The Processed Diet pattern was associated with obesity.
A major challenge in addressing the loss of benefits and services provided by the natural environment is that it can be difficult to find ways for those who benefit from them to pay for their preservation. We examine one such context in Malawi, where erosion from soils disturbed by agriculture affects not only farmers’ incomes, but also damages aquatic habitat and inhibits the storage and hydropower potential of dams downstream. We demonstrate that payments from hydropower producers to farmers to maintain land cover and prevent erosion can have benefits for all parties involved.
Since the discovery of periodic variability of Class II methanol masers associated with high-mass star formation, several possible driving mechanisms have been proposed to explain this phenomenon. Here the colliding wind binary (CWB) hypothesis is proposed to describe the periodic variability. It is shown that the recombination of a partially ionized gas describes the flare profiles remarkably well. In addition, the quiescent state flux density is also described remarkably well by the time-dependent change of the electron density. This suggests that the periodicity is caused by the time-dependent change in the radio free-free emission from the background HII regions against which the maser is projected.
The dwarf galaxies in the Local Group (LG) reveal a surprising amount of spatial structuring. In particular, almost all non-satellite dwarfs belong to one of two planes that show a very pronounced symmetry. In order to determine if these structures in the LG are dynamically stable or, alternatively, if they only represent transient alignments, proper motion measurements of these galaxies are required. A viable method to derive proper motions is offered by VLBI studies of 22-GHz water (and 6.7-GHz methanol) maser lines in star-forming regions.
In 2016, in the framework of the Early Science Program of the Sardinia Radio Telescope (SRT), we have conducted an extensive observational campaign to map the entire optical body of all the LG dwarf galaxies that belong to the two planes, at C and K band, in a search for methanol and water maser emission.
Here, we outline the project and present its first results on 3 targets, NGC 6822, IC 1613, and WLM. While no luminous maser emission has been detected in these galaxies, a number of interesting weaker detections has been obtained, associated with particularly active star forming regions. In addition, we have produced deep radio continuum maps for these galaxies, aimed at investigating their star forming activity and providing an improved assessment of star formation rates in these galaxies.
We present polarimetric observations of the 4 ground-state transitions of OH, toward a sample of maser-emitting planetary nebulae (PNe) using the Australia Telescope Compact Array. This sample includes confirmed OH-emitting PNe, confirmed and candidate H2O-maser-emitting PNe. Polarimetric observations provide information related to the magnetic field of these sources. Maser-emitting PNe are very young PNe and magnetic fields are a key ingredient in the early evolution and shaping process of PNe. Our preliminary results suggest that magnetic field strengths may change very rapidly in young PNe.
We present Kitty, an unprecedented and near simultaneous flaring event in ten transitions (6 hydroxyl, 1 water and 3 methanol), that began on 1 January 2015 in the massive star-forming region NGC6334F located in the Cat’s Paw Nebula. The brightest components in each transition increased by factors of 20 to 70 in line with a factor of ~70 increase in dust emission luminosity for the source MM1. We also report the detection of only the fifth known 4.660 GHz hydroxyl maser and that it varied in a correlated fashion with 1.720, 6.031, and 6.035 GHz hydroxyl counterparts. We postulate that if Kitty, and two historical flares in 1965 & 1999, are accretion events and are caused by the successive passages of a secondary star disrupting the accretion disk, where the frequency of occurrence is cycling down at a rate of ~2.2, it is possible another event will occur in 2022.
The first periodic Class II methanol maser was reported on in 2003. Since that time, a number of different monitoring programmes have found periodic masers, as well as other modes of variability. In a few cases, periodicity has been found in other maser species such as formaldehyde and water. Several distinct characteristics of light curves have been noted, possibly pointing to different underlying mechanisms for periodicity if one assumes a linear response to incoming radiation. I will give a brief overview of the known periodic sources, discuss current theories, and present new results obtained from monitoring mainline hydroxyl masers using the seven-element Karoo Array Telescope (KAT-7) during its science verification phase.
The interferometric and single-dish observations of the Extended Green Objects sample have been carried out in order to check the possible common pumping mechanism of class I methanol maser (cIMM) and OH(1720 MHz) maser and their identification with a front of bipolar outflow as a source of interstellar shock stimulating collisional pumping of the molecules. High spatial and spectral resolution observations of OH masers allow us to investigate structure, kinematics, and magnetic field configuration of the inner region of the source, i.e., the outflow ejection region. Analysis of magnetic field strength in a disk area is crucial to understanding of the outflow origin.
Theoretical simulations have shown that magnetic fields play an important role in massive star formation: they can suppress fragmentation in the star forming cloud, enhance accretion via disc and regulate outflows and jets. However, models require specific magnetic configurations and need more observational constraints to properly test the impact of magnetic fields. We investigate the magnetic field structure of the massive protostar IRAS18089-1732, analysing 6.7 GHz CH3OH maser MERLIN observations. IRAS18089-1732 is a well studied high mass protostar, showing a hot core chemistry, an accretion disc and a bipolar outflow. An ordered magnetic field oriented around its disc has been detected from previous observations of polarised dust. This gives us the chance to investigate how the magnetic field at the small scale probed by masers relates to the large scale field probed by the dust.