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Italian ryegrass [Lolium perenne L. spp. multiflorum (Lam.) Husnot] is one of the most troublesome weeds worldwide. L. multiflorum is also a grass seed crop cultivated on 50,000 ha in Oregon, where both diploid and tetraploid cultivars are grown. A survey was conducted to understand the distribution, frequency, and susceptibility of L. multiflorum to selected herbicides used to control L. multiflorum. The herbicides selected were clethodim, glufosinate, glyphosate, mesosulfuron-methyl (mesosulfuron), paraquat, pinoxaden, pyroxsulam, quizalofop-P-ethyl (quizolafop), pronamide, flufenacet + metribuzin, and pyroxasulfone. The ploidy levels of the populations were also tested. A total of 150 fields were surveyed between 2017 and 2018, of which 75 (50%) had L. multiflorum present. Herbicide-resistant populations were documented in 88% of the 75 populations collected. The most frequent mechanisms of action were resistance to Acetyl-CoA carboxylase (ACCase), Acetolactate Synthase (ALS), 5-enolpyruvylshikimate-3-phosphate (EPSPs) inhibitors, and combinations thereof. Multiple and cross-resistance, found in 75% of the populations, were the most frequent patterns of resistance. Paraquat-resistant biotypes were confirmed in six orchard crop populations for the first time in Oregon. Herbicide resistance was spatially clustered, with most cases of resistance in the northern part of the surveyed area. ALS and ACCase resistant populations were prevalent in wheat (Triticum aestivum L.) fields. Multiple-resistance was positively correlated with plant density. Tetraploid feral populations were identified, but no cases of herbicide resistance were documented. This is the first survey of herbicide resistance and ploidy diversity in L. multiflorum in western Oregon. Resistant populations were present across the surveyed area, indicating that the problem is widespread.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
George L. Cowgill had a major influence on the study of the ancient city of Teotihuacan and the development and promotion of quantitative methods in archaeology. His wit, teaching, and research influenced many in the profession. We draw on two published autobiographical works (Cowgill 2008a, 2013a), some unpublished autobiographical notes (Cowgill 1983), his many publications, and our own associations with George.
A single radiocarbon date derived from the Buhl burial in south-central Idaho has frequently been used as a data point for the interpretation of the Western Stemmed Tradition (WST) chronology and technology because of the stemmed biface found in situ with the human remains. AMS dating of bone collagen in 1991 produced an age of 10,675 ± 95 14C BP, immediately postdating the most widely accepted age range for Clovis. The Buhl burial has been cited as evidence that stemmed point technology may have overlapped with Clovis technology in the Intermountain West. We discuss concerns about the radiocarbon date, arguing that even at face value, the calibrated date has minimal overlap with Clovis at the 95.4% range. Furthermore, the C:N ratio of 3.69 in the analyzed collagen is outside of the typical range for well-preserved samples, indicating a postdepositional change in carbon composition, which may make the date erroneously older or younger than the age of the skeleton. Finally, the potential dietary incorporation of small amounts of anadromous fish may indicate that the burial is younger than traditionally accepted. For these reasons, we argue that the Buhl burial cannot be used as evidence of overlap between WST and Clovis.
Raw milk cheeses are commonly consumed in France and are also a common source of foodborne outbreaks (FBOs). Both an FBO surveillance system and a laboratory-based surveillance system aim to detect Salmonella outbreaks. In early August 2018, five familial FBOs due to Salmonella spp. were reported to a regional health authority. Investigation identified common exposure to a raw goats' milk cheese, from which Salmonella spp. were also isolated, leading to an international product recall. Three weeks later, on 22 August, a national increase in Salmonella Newport ST118 was detected through laboratory surveillance. Concomitantly isolates from the earlier familial clusters were confirmed as S. Newport ST118. Interviews with a selection of the laboratory-identified cases revealed exposure to the same cheese, including exposure to batches not included in the previous recall, leading to an expansion of the recall. The outbreak affected 153 cases, including six cases in Scotland. S. Newport was detected in the cheese and in the milk of one of the producer's goats. The difference in the two alerts generated by this outbreak highlight the timeliness of the FBO system and the precision of the laboratory-based surveillance system. It is also a reminder of the risks associated with raw milk cheeses.
Effective management of uncertainty can lead to better, more informed decisions. However, many decision makers and their advisers do not always face up to uncertainty, in part because there is little constructive guidance or tools available to help. This paper outlines six Uncertainty Principles to manage uncertainty.
Face up to uncertainty
Deconstruct the problem
Don’t be fooled (un/intentional biases)
Models can be helpful, but also dangerous
Think about adaptability and resilience
Bring people with you
These were arrived at following extensive discussions and literature reviews over a 5-year period. While this is an important topic for actuaries, the intended audience is any decision maker or advisor in any sector (public or private).
Attention deficit hyperactivity disorder (ADHD) is highly heritable and is associated with lower educational attainment. ADHD is linked to family adversity, including hostile parenting. Questions remain regarding the role of genetic and environmental factors underlying processes through which ADHD symptoms develop and influence academic attainment.
This study employed a parent-offspring adoption design (N = 345) to examine the interplay between genetic susceptibility to child attention problems (birth mother ADHD symptoms) and adoptive parent (mother and father) hostility on child lower academic outcomes, via child ADHD symptoms. Questionnaires assessed birth mother ADHD symptoms, adoptive parent (mother and father) hostility to child, early child impulsivity/activation, and child ADHD symptoms. The Woodcock–Johnson test was used to examine child reading and math aptitude.
Building on a previous study (Harold et al., 2013, Journal of Child Psychology and Psychiatry, 54(10), 1038–1046), heritable influences were found: birth mother ADHD symptoms predicted child impulsivity/activation. In turn, child impulsivity/activation (4.5 years) evoked maternal and paternal hostility, which was associated with children's ADHD continuity (6 years). Both maternal and paternal hostility (4.5 years) contributed to impairments in math but not reading (7 years), via impacts on ADHD symptoms (6 years).
Findings highlight the importance of early child behavior dysregulation evoking parent hostility in both mothers and fathers, with maternal and paternal hostility contributing to the continuation of ADHD symptoms and lower levels of later math ability. Early interventions may be important for the promotion of child math skills in those with ADHD symptoms, especially where children have high levels of early behavior dysregulation.
Meal timing may influence food choices, neurobiology and psychological states. Our exploratory study examined if time-of-day eating patterns were associated with mood disorders among adults.
During 2004–2006 (age 26–36 years) and 2009–2011 (follow-up, age 31–41 years), N = 1304 participants reported 24-h food and beverage intake. Time-of-day eating patterns were derived by principal components analysis. At follow-up, the Composite International Diagnostic Interview measured lifetime mood disorder. Log binomial and adjacent categories log-link regression were used to examine bidirectional associations between eating patterns and mood disorder. Covariates included sex, age, marital status, social support, education, work schedule, body mass index and smoking.
Three patterns were derived at each time-point: Grazing (intake spread across the day), Traditional (highest intakes reflected breakfast, lunch and dinner), and Late (skipped/delayed breakfast with higher evening intakes). Compared to those in the lowest third of the respective pattern at baseline and follow-up, during the 5-year follow-up, those in the highest third of the Late pattern at both time-points had a higher prevalence of mood disorder [prevalence ratio (PR) = 2.04; 95% confidence interval (CI) 1.20–3.48], and those in the highest third of the Traditional pattern at both time-points had a lower prevalence of first onset mood disorder (PR = 0.31; 95% CI 0.11–0.87). Participants who experienced a mood disorder during follow-up had a 1.07 higher relative risk of being in a higher Late pattern score category at follow-up than those without mood disorder (95% CI 1.00–1.14).
Non-traditional eating patterns, particularly skipped or delayed breakfast, may be associated with mood disorders.
Weed management is a major challenge in organic crop production, and organic farms generally harbor larger weed populations and more diverse communities compared with conventional farms. However, little research has been conducted on the effects of different organic management practices on weed communities and crop yields. In 2014 and 2015, we measured weed community structure and soybean [Glycine max (L.) Merr.] yield in a long-term experiment that compared four organic cropping systems that differed in nutrient inputs, tillage, and weed management intensity: (1) high fertility (HF), (2) low fertility (LF), (3) enhanced weed management (EWM), and (4) reduced tillage (RT). In addition, we created weed-free subplots within each system to assess the impact of weeds on soybean yield. Weed density was greater in the LF and RT systems compared with the EWM system, but weed biomass did not differ among systems. Weed species richness was greater in the RT system compared with the EWM system, and weed community composition differed between RT and other systems. Our results show that differences in weed community structure were primarily related to differences in tillage intensity, rather than nutrient inputs. Soybean yield was lower in the EWM system compared with the HF and RT systems. When averaged across all four cropping systems and both years, soybean yield in weed-free subplots was 10% greater than soybean yield in the ambient weed subplots that received standard management practices for the systems in which they were located. Although weed competition limited soybean yield across all systems, the EWM system, which had the lowest weed density, also had the lowest soybean yield. Future research should aim to overcome such trade-offs between weed control and yield potential, while conserving weed species richness and the ecosystem services associated with increased weed diversity.
We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
The aim of the present study is to use the syndemic framework to investigate the risk of contracting HIV in the US population. Cross-sectional analyses are from The National Health and Nutrition Examination Survey. We extracted and aggregated data on HIV antibody test, socio-demographic characteristics, alcohol use, drug use, depression, sexual behaviours and sexually transmitted diseases from cycle 2009–2010 to 2015–2016. We carried out weighted regression among young adults (20–39 years) and adults (40–59 years) separately. In total, 5230 men and 5794 women aged 20–59 years were included in the present analyses. In total, 0.8% men and 0.2% women were tested HIV-positive. Each increasing HIV risk behaviour was associated with elevated odds of being tested HIV-positive (1.15, 95% CI 1.15–1.15) among young adults and adults (1.61, 95% CI 1.61–1.61). Multi-faceted, community-based interventions are urgently required to reduce the incidence of HIV in the USA.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Objective: To investigate the effects of methylphenidate on long-term executive and neuropsychological functioning in children with attention problems following TBI, as well as the relationship between methylphenidate associated changes in lab-based neuropsychological measures of attentional control, processing speed, and executive functioning and parent- or self-report measures of everyday executive functioning. Method: 26 children aged 6–17 years, who were hospitalized for moderate-to-severe blunt head trauma 6 or more months previously, were recruited from a large children’s hospital medical center. Participants were randomized into a double-masked, placebo-controlled cross-over clinical trial. Participants completed a comprehensive neuropsychological battery and parent- and self-report ratings of everyday executive functioning at baseline, and at 4 weeks and 8 weeks following upward titration of medication to an optimal dose or while administered a placebo. Results: Methylphenidate was associated with significant improvements in processing speed, sustained attention, and both lab-based and everyday executive functioning. Significant treatment-by-period interactions were found on a task of sustained attention. Participants who were randomized to the methylphenidate condition for the first treatment period demonstrated random or erratic responding, with slower and more variable response times when given placebo during the second period. Conclusion: Results indicate that methylphenidate treatment is associated with positive outcomes in processing speed, sustained attention, and both lab-based and everyday measures of executive functioning compared to placebo group. Additionally, results suggest sustained attention worsens when discontinuing medication. (JINS, 2019, 25, 740–749)
Determining infectious cross-transmission events in healthcare settings involves manual surveillance of case clusters by infection control personnel, followed by strain typing of clinical/environmental isolates suspected in said clusters. Recent advances in genomic sequencing and cloud computing now allow for the rapid molecular typing of infecting isolates.
To facilitate rapid recognition of transmission clusters, we aimed to assess infection control surveillance using whole-genome sequencing (WGS) of microbial pathogens to identify cross-transmission events for epidemiologic review.
Clinical isolates of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, and Klebsiella pneumoniae were obtained prospectively at an academic medical center, from September 1, 2016, to September 30, 2017. Isolate genomes were sequenced, followed by single-nucleotide variant analysis; a cloud-computing platform was used for whole-genome sequence analysis and cluster identification.
Most strains of the 4 studied pathogens were unrelated, and 34 potential transmission clusters were present. The characteristics of the potential clusters were complex and likely not identifiable by traditional surveillance alone. Notably, only 1 cluster had been suspected by routine manual surveillance.
Our work supports the assertion that integration of genomic and clinical epidemiologic data can augment infection control surveillance for both the identification of cross-transmission events and the inclusion of missed and exclusion of misidentified outbreaks (ie, false alarms). The integration of clinical data is essential to prioritize suspect clusters for investigation, and for existing infections, a timely review of both the clinical and WGS results can hold promise to reduce HAIs. A richer understanding of cross-transmission events within healthcare settings will require the expansion of current surveillance approaches.
A medical information commons (MIC) is a networked data environment utilized for research and clinical applications. At three deliberations across the U.S., we engaged 75 adults in two-day facilitated discussions on the ethical and social issues inherent to sharing data with an MIC. Deliberants made recommendations regarding opt-in consent, transparent data policies, public representation on MIC governing boards, and strict data security and privacy protection. Community engagement is critical to earning the public's trust.
Adverse pregnancy outcomes including prematurity and low birth weight (LBW) have been associated with life-long chronic disease risk for the infant. Stress during pregnancy increases the risk of adverse pregnancy outcomes. Many studies have reported the incidence of adverse pregnancy outcomes in Indigenous populations and a smaller number of studies have measured rates of stress and depression in these populations. This study sought to examine the potential association between stress during pregnancy and the rate of adverse pregnancy outcomes in Australian Indigenous women residing in rural and remote communities in New South Wales. This study found a higher rate of post-traumatic stress disorder, depression and anxiety symptoms during pregnancy than the general population. There was also a higher incidence of prematurity and LBW deliveries. Unfortunately, missing post-traumatic stress disorder and depressive symptomatology data impeded the examination of associations of interest. This was largely due to the highly sensitive nature of the issues under investigation, and the need to ensure adequate levels of trust between Indigenous women and research staff before disclosure and recording of sensitive research data. We were unable to demonstrate a significant association between the level of stress and the incidence of adverse pregnancy outcomes at this stage. We recommend this longitudinal study continue until complete data sets are available. Future research in this area should ensure prioritization of building trust in participants and overestimating sample size to ensure no undue pressure is placed upon an already stressed participant.
With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
We describe the motivation and design details of the ‘Phase II’ upgrade of the Murchison Widefield Array radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the Murchison Widefield Array in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing array core. These new tiles enhance the surface brightness sensitivity of the array and will improve the ability of the Murchison Widefield Array to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ∼3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u, v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of Murchison Widefield Array continuum images. The upgrade retains all of the features that have underpinned the Murchison Widefield Array’s success (large field of view, snapshot image quality, and pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies.