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Introduction: Optimizing naloxone dosing in the context of increasing fentanyl and ultra-potent opioid (UPO) prevalence is an important consideration for emergency health care providers. The goal of this systematic review was to evaluate the association between initial and cumulative naloxone doses on effective reversal and adverse events in undifferentiated and fentanyl/UPO overdoses. Methods: We searched Embase, MEDLINE, Cochrane Central Register of Controlled Trials, DARE, CINAHL, Science Citation Index, reference lists, toxicology websites, and conference proceedings from July to October 2018 and back to 1972. Our search included pertinent indexing terms for UPOs. We included interventional and observational studies reporting on naloxone administration for opioid toxicity reversal in people ≥12 years old. Additionally, we accessed non-traditional evidence sources (case reports and series) given this rapidly changing field. We conducted inclusion screens, data extraction and quality assessments in duplicate. We summarized study characteristics and where reported, analyzed number of patients with clinical response. Response was defined as not receiving further naloxone doses and remaining alive. Results: We included 174 studies (108 case reports and series, 55 observational, 9 interventional) with 26,660 subjects (median age 35.1; 74.2% male). We observed lower response among patients exposed to fentanyl/UPO versus heroin for initial naloxone doses ≤0.4mg (56.8% versus 80.2%) and > 0.4mg (27.0% versus 82.1%). Mean cumulative doses were higher for fentanyl/UPO (2.10 mg, SD 1.80 mg) versus heroin (1.48 mg, SD 1.68 mg) overdoses. In North American studies the median cumulative dose used was higher for fentanyl/UPO versus heroin overdoses. A dose-response curve for fentanyl/UPO studies showed marked variability in doses among responders, indicating heterogeneity. Adverse events reporting was inconsistent; 10% of subjects experienced withdrawal based on studies in which they were reported. Conclusion: This is the first systematic review to summarize proportion of patients with clinical response by naloxone dose provided. While variable reporting, study quality, heterogeneity, and our outcome definitions limit the conclusions we can draw, it appears that higher initial doses and in some cases, higher cumulative naloxone doses were used and may be necessary to reverse toxicity due to fentanyl/UPO compared to other opioids. High-quality prospective studies assessing effectiveness and safety are needed.
Introduction: Effective communication to develop a shared understanding of patient expectations is critical to a positive encounter in the Emergency Department (ED). However, there is limited research examining Patient/Caregiver (P/C ) expectations in the ED and what factors lead to P/C presentation. This study aims to address this gap by answering the following questions: 1) What are common P/C reported factors affecting ED presentation? 2) What are common P/C expectations of an ED visit? 3) How do P/C expectations vary based on ED site or factors affecting presentation in the ED? Methods: The Preparing Emergency Patients and Providers (PrEPP) tool was designed to collect P/C expectations, worries, perceived causes of symptoms, and factors affecting presentation from a convenience sample of patient visits to the emergency department (ED). The PrEPP tool was provided to all P/Cs with CTAS 2-5 when they registered at one of 4 EDs in the Halifax area from January to June 2016. Completed tools were collected in a REDCap database where qualitative data was coded into categories (i.e. presenting illness, injury). Descriptive and chi-squared statistical analyses were performed. Results: In total, 11,418 PrEPP tools were collected; representing 12% of the total ED visits to the 4 ED sites during the study period. The main factors affecting ED presentation were: self-referral 68%, family/friends 20%, telehealth 8%, unable to see their GP 7%, GP referral 6%, or walk-in-clinic 5%. P/Cs main causes of worry were: presenting illness 19%, injury 15%, or pain 14%. The main expectations for the ED visit were to get a: physician's opinion 73%, x-ray 40%, or blood test 20%. Most P/Cs indicated they did not expect medication during (63%), or after (66%), their ED visit. There were significant differences in P/C expectations between adult and pediatric EDs (χ2 = 720.949, df = 14, P = 0.000) and those P/Cs unable or able to access primary care prior to ED presentation (χ2 = 38.980, df = 1, P = 0.000). The rate of expecting a physician's opinion at the pediatric ED was higher than the adult ED (77.6% vs 70.9%), while lower for expecting CT/MRIs (4.6% vs 11.4%). P/Cs who were unable to access primary care prior to ED presentation expected services which were available at primary care at a higher rate than those who accessed primary care (58.5% vs 36.7%). Conclusion: Our findings identify some of the factors that influence P/C's decision to present to the ED and their expectations of the ED visit.
Introduction: Effective communication to develop a shared understanding of patient/caregiver (P/C) expectations is critical during emergency department (ED) encounters. However, there is limited research examining the use of communication tools of P/C expectations to improve communication in the ED. The objective of this study was to examine satisfaction with a patient expectations questionnaire, known as the PrEPP tool, and its impact on communication and management of patients in the ED. Methods: The PrEPP tool collected P/C expectations over 3 phases of the study. In phase1, the PrEPP tool was distributed to all P/Cs (CTAS score of 2 to 5) in four EDs in Nova Scotia. In phase 2 the PrEPP tool was refined to a 5-item questionnaire. In phase 3 the PrEPP tool was re-implemented over a six-month period. Follow-up surveys were distributed to P/Cs via email (phase 1, 3) and HCPs on iPads in the ED (phase 3) to determine the impact of the tool on communication and management of patients. Entries were compiled on a REDCap database and descriptive statistics were used to analyze responses related to satisfaction.The PrEPP tool collected P/C expectations over 3 phases of the study. In phase1, the PrEPP tool was distributed to all P/Cs (CTAS score of 2 to 5) in four EDs in Nova Scotia. In phase 2 the PrEPP tool was refined to a 5-item questionnaire. In phase 3 the PrEPP tool was re-implemented over a six-month period. Follow-up surveys were distributed to P/Cs via email (phase 1, 3) and HCPs on iPads in the ED (phase 3) to determine the impact of the tool on communication and management of patients. Entries were compiled on a REDCap database and descriptive statistics were used to analyze responses related to satisfaction. Results: In Phase 1, 11418 PrEPP tools and 147 surveys (29% response rate) were collected from January-June 2016. The majority of P/Cs found the PrEPP questionnaire easy to complete (95.9%) and felt HCPs met their expectations (87.1%). In Phase 3, 951 P/C (31.1% response rate) and 128 HCP surveys were collected. Of P/C respondents 45.9% felt PrEPP helped to communicate expectations, while 49.7% said that they would like to use it on future ED visits. The majority of P/C respondents (75.4%) indicated their expectations were met during their visit to the ED. Of those whose expectations were not met, 69% felt their expectations were not discussed. The majority of HCP respondents (90.4%) indicated they used the PrEPP tool at least sometimes. Also, 78.4% said it influenced patient communication and 42% indicated the tool influenced management of patients at least sometimes. Conclusion: Obtaining expectations early in the patient encounter may provide opportunities for improved communication in the ED. P/Cs found the PrEPP tool easy to use to communicate their expectations and HCPs felt it influenced communication and management of patients in the ED. Further qualitative thematic analysis is needed to explore how the PrEPP tool impacted ED visits.
The triazines are one of the most widely used herbicide classes ever developed and are critical for managing weed populations that have developed herbicide resistance. These herbicides are traditionally valued for their residual weed control in more than 50 crops. Scientific literature suggests that atrazine, and perhaps other s-triazines, may no longer remain persistent in soils due to enhanced microbial degradation. Experiments examined the rate of degradation of atrazine and two other triazine herbicides, simazine and metribuzin, in both atrazine-adapted and non-history Corn Belt soils, with similar soils being used from each state as a comparison of potential triazine degradation. In three soils with no history of atrazine use, the t1/2 of atrazine was at least four times greater than in three soils with a history of atrazine use. Simazine degradation in the same three sets of soils was 2.4 to 15 times more rapid in history soils than non-history soils. Metribuzin in history soils degraded at 0.6, 0.9, and 1.9 times the rate seen in the same three non-history soils. These results indicate enhanced degradation of the symmetrical triazine simazine, but not of the asymmetrical triazine metribuzin.
Introduction: Discharge communication in the emergency department occurs frequently and has been identified as an important, underestimated problem. Tools, such as patient or caregiver-held passports have been used in other departments to improve communication and facilitate provider and patient decision making. The objective of this review was to identify what modalities, methods and designs have been used and evaluated when implementing a communication tool or passport type document in the emergency department setting. Methods: This review was conducted following Joanna Briggs Institute methodology. Iterative steps included identifying the research question, identifying relevant studies, data extraction and synthesis. Keywords and indexed terms were used to search PubMed, Cinahl, Embase and Web of Science. The reference list of all identified reports and articles from that search were reviewed for additional studies and a hand search of the last 5 years of Annals of Emergency Medicine and the Canadian Journal of Emergency Medicine was completed. Inclusion criteria were set to select studies investigating either patients, caregivers or health care providers use of passports, communication documents or journals with the goal of improving any aspect of communication in the emergency department setting. Results: Of the 81 potential publications screened, only 4 met inclusion criteria for extraction. 1 reviewed a passport that aimed at pediatric pain management in settings that include the emergency department, 2 of the publications reported on the same project which developed a passport for asthma patients and 1 discussed a passport for patients with learning disabilities. All the included publications were published in and discuss passports that were developed for use in the UK. Descriptions of implementation, evaluation and perception of the passports in these publications was limited. Conclusion: This scoping review has revealed a major gap in the current literature on communication tools in the emergency department, a department where communication, especially about discharge is of utmost importance. The included studies focused on very different patient populations and aim to improve different outcomes and therefore dont allow us to make for passports aimed at helping the general emergency department population.
Introduction: TREKK is a national knowledge mobilization network of clinicians, researchers and parents aimed at improving emergency care for children by increasing collaborations between general and pediatric emergency departments (ED). This study aimed to determine patterns of knowledge sharing within the network and identify connections, barriers and opportunities to obtaining pediatric information and training. Methods: Social network analysis (SNA) uses network theory to understand patterns of interaction. Two SNAs were conducted in 2014 and 2015 using an online network survey distributed to 37 general EDs. Data was analyzed using UCI Net and Netdraw to identify connections, knowledge sharing and knowledge brokers within the network. Building on these results, we then conducted 22 semi-structured follow-up interviews (2016) with healthcare professionals (HCPs) at General EDs across Canada, purposefully sampled to include individuals from connected and disconnected sites, as identified in the SNA. Interviews were analyzed by 2 reviewers using content and thematic analysis. Results: SNA data was analyzed for 135 participants across the network. Results from 2014 showed that the network was divided along provincial lines, with most individuals connecting with colleagues within their own institution. Results from 2015 showed more inter-site interconnectivity and a reduction in isolated sites over time from 17 to 3. Interview participants included physicians (59%) and nurses (41%) from 18 general EDs in urban (68%) and rural/remote (32%) Canada. HCPs sought information both formally and informally, by using guidelines, talking to colleagues, and attending pediatric related training sessions. Network structure and processes were felt to increase connections, support practice change, and promote standards of care. Participants identified personal, organizational and system-level barriers to information and skill acquisition, including resources and personal costs, geography, dissemination, and time. Providing easy access to information at the point of care was promoted through enhancing content visibility and by embedding resources into local systems. There remains a need to share successful methods of local dissemination and implementation across the network, and to leverage local professional champions such as clinical nurse liaisons. Conclusion: This study highlights the power of a network to increase connections between HCPs working in general and pediatric EDs. Findings reinforce the critical role of ongoing network evaluation to improve the design and delivery of knowledge mobilization initiatives.
Annually dated ice cores from West and East Antarctica provide proxies for past changes in atmospheric circulation over Antarctica and portions of the Southern Ocean, temperature in coastal West and East Antarctica, and the frequency of South Polar penetration of El Niño events. During the period AD 1700–1850, atmospheric circulation over the Antarctic and at least portions of the Southern Hemisphere underwent a mode switch departing from the out-of-phase alternation of multi-decadal long phases of EOF1 and EOF2 modes of the 850 hPa field over the Southern Hemisphere (as defined in the recent record by Thompson and Wallace, 2000; Thompson and Solomon, 2002) that characterizes the remainder of the 700 year long record. From AD 1700 to 1850, lower-tropospheric circulation was replaced by in-phase behavior of the Amundsen Sea Low component of EOF2 and the East Antarctic High component of EOF1. During the first phase of the mode switch, both West and East Antarctic temperatures declined, potentially in response to the increased extent of sea ice surrounding both regions. At the end of the mode switch, West Antarctic coastal temperatures rose and East Antarctic coastal temperatures fell, respectively, to their second highest and lowest of the record. Polar penetration of El Niño events increased during the mode switch. The onset of the AD 1700–1850 mode switch coincides with the extreme state of the Maunder Minimum in solar variability. Late 20th-century West Antarctic coastal temperatures are the highest in the record period, and East Antarctic coastal temperatures close to the lowest. Since AD 1700, extratropical regions of the Southern Hemisphere have experienced significant climate variability coincident with changes in both solar variability and greenhouse gases.
An updated compilation of published and new data of major-ion (Ca, Cl, K, Mg, Na, NO3, SO4) and methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes of Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, the United Kingdom, the United States and the national Antarctic programme of Finland. The comparison shows that snow chemistry concentrations vary by up to four orders of magnitude across Antarctica and exhibit distinct geographical patterns. The Antarctic-wide comparison of glaciochemical records provides a unique opportunity to improve our understanding of the fundamental factors that ultimately control the chemistry of snow or ice samples. This paper aims to initiate data compilation and administration in order to provide a framework for facilitation of Antarctic-wide snow chemistry discussions across all ITASE nations and other contributing groups. The data are made available through the ITASE web page (http://www2.umaine.edu/itase/content/syngroups/snowchem.html) and will be updated with new data as they are provided. In addition, recommendations for future research efforts are summarized.
We present highly resolved, annually dated, calibrated proxies for atmospheric circulation from several Antarctic ice cores (ITASE (International Trans-Antarctic Scientific Expedition), Siple Dome, Law Dome) that reveal decadal-scale associations with a South Pole ice-core 10Be proxy for solar variability over the last 600 years and annual-scale associations with solar variability since AD 1720. We show that increased (decreased) solar irradiance is associated with increased (decreased) zonal wind strength near the edge of the Antarctic polar vortex. The association is particularly strong in the Indian and Pacific Oceans and as such may contribute to understanding climate forcing that controls drought in Australia and other Southern Hemisphere climate events. We also include evidence suggestive of solar forcing of atmospheric circulation near the edge of the Arctic polar vortex based on ice-core records from Mount Logan, Yukon Territory, Canada, and both central and south Greenland as enticement for future investigations. Our identification of solar forcing of the polar atmosphere and its impact on lower latitudes offers a mechanism for better understanding modern climate variability and potentially the initiation of abrupt climate-change events that operate on decadal and faster scales.
Cannabis and tobacco have contrasting cognitive effects. Smoking cannabis with tobacco is prevalent in many countries and although this may well influence cognitive and mental health outcomes, the possibility has rarely been investigated in human experimental psychopharmacological research.
The individual and interactive effects of cannabis and tobacco were evaluated in 24 non-dependent cannabis and tobacco smokers in a randomized, placebo-controlled, double-blind, 2 (cannabis, placebo) × 2 (tobacco, placebo) crossover design. Verbal memory (prose recall), working memory (WM) performance including maintenance, manipulation and attention (N-back), psychotomimetic, subjective and cardiovascular measures were recorded on each of four sessions.
Cannabis alone impaired verbal memory. A priori contrasts indicated that tobacco offset the effects of cannabis on delayed recall. However, this was not supported by linear mixed model analysis. Cannabis load-dependently impaired WM. By contrast, tobacco improved WM across all load levels. The acute psychotomimetic effects and ratings of ‘stoned’ and ‘dizzy’ induced by cannabis were not altered by tobacco. Cannabis and tobacco had independent effects on increasing heart rate and interacting effects on increasing diastolic blood pressure.
Relative to placebo, acute cannabis impaired verbal memory and WM. Tobacco enhanced performance on WM, independently of cannabis. Moreover, we found some preliminary evidence that tobacco may offset the effects of cannabis on delayed, but not immediate, verbal recall. In contrast, the psychotomimetic and subjective effects of cannabis were unaffected by tobacco co-administration. By reducing the cognitive impairment from cannabis, tobacco co-administration may perpetuate use despite adverse health consequences.
Introduction: Effective communication to develop a shared understanding of patient expectations is critical in establishing a positive medical encounter in the emergency department (ED). However, there is limited research examining patient/caregiver expectations in the ED, and their impact on the beliefs, attitudes and behaviours during and after an ED visit. The objective of this study is to examine patient/caregiver expectations and satisfaction with care in the ED using a patient expectation questionnaire and a follow up survey. Methods: As a part of a larger 3-phase study on patient/caregiver expectations in adult and pediatric EDs, a 7-item, paper-based questionnaire was distributed to all patients and/or caregivers who presented to one of four EDs in Nova Scotia with a Canadian Triage and Acuity Scale (CTAS) score of 2 to 5. A follow-up survey was distributed to all willing participants via email to determine their satisfaction with care received in ED. Descriptive statistics were used to analyze responses. Results: Phase 1 was conducted from January to September 2016. In total, 24,788 expectation questionnaires were distributed to ED patients/caregivers, 11,571 were collected (47% response rate), and 509 patients were contacted for a follow-up survey. Preliminary analysis of 4,533 questionnaires shows the majority of patients (67.1%) made the decision by themselves to present to the ED, while others were advised by a family/friend (22%). Respondents were most worried about an injury (17.8%) followed by illness (15.6%) and expected to talk to a physician (69.9%) and receive an x-ray (39.3%). The majority of physicians (53.3%) reported the expectation tool helped in caring for the patient and 87.5% felt they met patient expectations. There were 147 patient/caregiver responses to a follow-up survey (29% response rate) and 87.1% of responders reported that ED clinicians met their expectations. Conclusion: Patient/caregivers have a variety of concerns, questions, and expectations when presenting to the ED. Obtaining expectations early in the patient encounter may provide opportunities for improved communication between clinicians and patients while enhancing satisfaction with care received. Further analysis is needed to determine the impact of the expectation questionnaire on productivity in the ED.
Cannabis is a widely used drug associated with increased risk for psychosis. The dopamine hypothesis of psychosis postulates that altered salience processing leads to psychosis. We therefore tested the hypothesis that cannabis users exhibit aberrant salience and explored the relationship between aberrant salience and dopamine synthesis capacity.
We tested 17 cannabis users and 17 age- and sex-matched non-user controls using the Salience Attribution Test, a probabilistic reward-learning task. Within users, cannabis-induced psychotic symptoms were measured with the Psychotomimetic States Inventory. Dopamine synthesis capacity, indexed as the influx rate constant Kicer, was measured in 10 users and six controls with 3,4-dihydroxy-6-[18F]fluoro-l-phenylalanine positron emission tomography.
There was no significant difference in aberrant salience between the groups [F1,32 = 1.12, p = 0.30 (implicit); F1,32 = 1.09, p = 0.30 (explicit)]. Within users there was a significant positive relationship between cannabis-induced psychotic symptom severity and explicit aberrant salience scores (r = 0.61, p = 0.04) and there was a significant association between cannabis dependency/abuse status and high implicit aberrant salience scores (F1,15 = 5.8, p = 0.03). Within controls, implicit aberrant salience was inversely correlated with whole striatal dopamine synthesis capacity (r = −0.91, p = 0.01), whereas this relationship was non-significant within users (difference between correlations: Z = −2.05, p = 0.04).
Aberrant salience is positively associated with cannabis-induced psychotic symptom severity, but is not seen in cannabis users overall. This is consistent with the hypothesis that the link between cannabis use and psychosis involves alterations in salience processing. Longitudinal studies are needed to determine whether these cognitive abnormalities are pre-existing or caused by long-term cannabis use.
Recent studies point to overlap between neuropsychiatric disorders in symptomatology and genetic aetiology.
To systematically investigate genomics overlap between childhood and adult attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and major depressive disorder (MDD).
Analysis of whole-genome blood gene expression and genetic risk scores of 318 individuals. Participants included individuals affected with adult ADHD (n = 93), childhood ADHD (n = 17), MDD (n = 63), ASD (n = 51), childhood dual diagnosis of ADHD–ASD (n = 16) and healthy controls (n = 78).
Weighted gene co-expression analysis results reveal disorder-specific signatures for childhood ADHD and MDD, and also highlight two immune-related gene co-expression modules correlating inversely with MDD and adult ADHD disease status. We find no significant relationship between polygenic risk scores and gene expression signatures.
Our results reveal disorder overlap and specificity at the genetic and gene expression level. They suggest new pathways contributing to distinct pathophysiology in psychiatric disorders and shed light on potential shared genomic risk factors.
Effective use of data linkage is becoming an increasingly important focus in the new healthcare system in England. We linked data from the results of a multiplex PCR assay for respiratory viruses for a population of 230 inpatients at a UK teaching hospital with their patient administrative system records in order to compare the mortality and length of stay of patients who tested positive for influenza A(H1N1)pdm09 with those positive for another influenza A virus. The results indicated a reduced risk of death among influenza A(H1N1)pdm09 patients compared to other influenza A strains, with an adjusted risk ratio of 0·25 (95% confidence interval 0·08–0·75, P = 0·01), while no significant differences were found between the lengths of stay in the hospital for these two groups. Further development of such methods to link hospital data in a routine fashion could provide a rapid means of gaining epidemiological insights into emerging infectious diseases.
On the surface, Propertius 1.2 seems to propound a traditional thesis, the superiority of unadorned beauty to artifice, and to scold Cynthia for not living up to this ideal of the natural. I believe that the ideal actually asserted is more complex than mere natural beauty and in fact paradoxically entails a large measure of artifice. Artifice itself becomes the central theme of the poem as its value is radically reinterpreted.
Part of the complexity comes from the fact that the ideal embraces more than physical appearance, whether adorned or not. A Catullan Parallel will illustrate. Propertius is here building upon and rivalling a Catullan poem, in a manner which has the effect of emphasizing the non-physical elements in his definition of ideal beauty. A poem on the nature of true female beauty in which the beloved is contrasted with other women and which attempts to define what is truly formosus (‘beautiful’ or ‘lovely’; cf. the insistent repetition of: forma 8 and 24, formosa 9, formosius 11) would immediately be recognized by the Roman reader as a challenge to Catullus 86, which centers on the word formosa.
Documenting capacity assessments and identifying substitute decisionmakers (SDMs) in healthcare facilities is ethically required for optimal patient care. Lack of such documentation has the potential to generate confusion and contention among patients, their family members, and members of the healthcare team. An overview of our research at the Ottawa Hospital and issues that influence the consistency of documentation in the Canadian context are presented here, as well as ideas for the mitigation of these issues and ways to encourage better documentation.
Cancer-related distress has been endorsed as the sixth vital sign by many international cancer organizations, and some countries such as Canada have implemented national screening for distress programs. The completion of a screening tool is an important first step in improving responsiveness to cancer-related distress, but screening must be followed with skilled supportive care to make a difference in patient-reported outcomes. Our objective was to create a web-based education program to support nurses and other frontline staff in providing an initial response to screening results.
To address screening and supportive care learning needs, the Canadian Association of Psychosocial Oncology (CAPO), with support from the Canadian Partnership Against Cancer, created a web-based education program as one component of the national screening for distress agenda. The program provides clinically grounded and interactive learning through the use of PowerPoint presentations, video clips of clinical interactions with patients and family members, and test questions. Presentation topics include, for example, strategies for dealing with screening results, managing referrals, and supportive counseling. We employed a matched pairs, pre-post survey design to assess the effect of the education program on confidence in screening and in providing initial supportive care.
Our analysis of the first 147 matched pairs to complete the course suggests that satisfaction with the course was high. Statistically significant increases in confidence in relation to screening for distress and assessing distress, and in providing initial supportive care, were evident.
Significance of results:
Our ongoing experience with CAPO's Interprofessional Psychosocial Oncology Distance Education (IPODE) project (www.ipode.ca) project suggests that healthcare professionals value web-based learning for its accessibility and convenience. Such programs appear to offer excellent opportunities for cost-effective education that supports practice change.
Nonsynthetic herbicides offer a potentially useful addition to the suite of weed management tools available to organic growers, but limited information is available to guide the optimal use of these products. The objectives of this research were to (1) evaluate the efficacy of clove oil– and vinegar-based herbicides on weeds across multiple states, and (2) assess the potential role of temperature, relative humidity (RH), and cloud cover in explaining inter-state variations in results. From 2006 to 2008, a total of 20 field trials were conducted in seven states using an identical protocol. Seeds of brown mustard were sown and herbicides applied to both mustard and emerged weeds when mustard reached the three- to four-leaf stage. Treatments included clove oil at 2.5, 5, 7.5, and 10% v/v concentrations at 54 L ha−1, and vinegar at 5, 10, 15, and 20% v/v concentrations at 107 L ha−1. Results varied widely across trials. In general, concentrations of at least 7.5% for clove oil and 15% for vinegar were needed for adequate control of mustard. Both products were more effective at suppressing mustard than Amaranthus spp. or common lambsquarters. Poor control was observed for annual grasses. No significant effects of cloud cover on the efficacy of either product were detected. In contrast, RH was positively correlated with control of brown mustard by both clove oil and vinegar with improved control at higher RH. Temperature had no detectable effect on the efficacy of clove oil, but higher temperatures improved control of brown mustard by vinegar.
The Australian Square Kilometre Array Pathfinder (ASKAP) will give us an unprecedented opportunity to investigate the transient sky at radio wavelengths. In this paper we present VAST, an ASKAP survey for Variables and Slow Transients. VAST will exploit the wide-field survey capabilities of ASKAP to enable the discovery and investigation of variable and transient phenomena from the local to the cosmological, including flare stars, intermittent pulsars, X-ray binaries, magnetars, extreme scattering events, interstellar scintillation, radio supernovae, and orphan afterglows of gamma-ray bursts. In addition, it will allow us to probe unexplored regions of parameter space where new classes of transient sources may be detected. In this paper we review the known radio transient and variable populations and the current results from blind radio surveys. We outline a comprehensive program based on a multi-tiered survey strategy to characterise the radio transient sky through detection and monitoring of transient and variable sources on the ASKAP imaging timescales of 5 s and greater. We also present an analysis of the expected source populations that we will be able to detect with VAST.