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This editorial considers the value and nature of academic psychiatry by asking what defines the specialty and psychiatrists as academics. We frame academic psychiatry as a way of thinking that benefits clinical services and discuss how to inspire the next generation of academics.
A mathematical model for the effect of the spatial variation of the local evaporative flux on the evaporation of and deposition from a thin pinned particle-laden sessile droplet is formulated and solved. We then analyse the behaviour for a one-parameter family of local evaporative fluxes with the free parameter $n \, (>-1)$ that exhibits qualitatively different behaviours mimicking those that can be obtained by, for example, surrounding the droplet with a bath of fluid or using a mask with one or more holes in it to achieve a desired pattern of evaporation enhancement and/or suppression. We show that when $-1< n<1$ (including the special cases $n=-1/2$ of diffusion-limited evaporation into an unbounded atmosphere and $n=0$ of spatially uniform evaporation), all of the particles are eventually advected to the contact line, and so the final deposit is a ring deposit at the contact line, whereas when $n>1$ all of the particles are eventually advected to the centre of the droplet, and so the final deposit is at the centre of the droplet. In particular, the present work demonstrates that a singular (or even a non-zero) evaporative flux at the contact line is not an essential requirement for the formation of a ring deposit. In addition, we calculate the paths of the particles when diffusion is slower than both axial and radial advection, and show that in this regime all of the particles are captured by the descending free surface before eventually being deposited onto the substrate.
A detailed analysis of steady coating flow of a thin film of a viscous fluid on the outside of a uniformly rotating horizontal circular cylinder in the absence of surface-tension effects but in the presence of a non-uniform pressure distribution due to an irrotational airflow with circulation shows that the presence of the airflow can result in qualitatively different behaviour of the fluid film from that in classical coating flow. Full-film solutions corresponding to a continuous film of fluid covering the entire cylinder are possible only when the flux and mass of fluid do not exceed critical values, which are determined in terms of the non-dimensional parameters $F$ and $K$ representing the speed of the far-field airflow and the circulation of the airflow, respectively. The qualitative changes in the behaviour of the film thickness as $F$ and $K$ are varied are described. In particular, the film thickness can have as many as four stationary points and, in general, has neither top-to-bottom nor right-to-left symmetry. In addition, when the circulation of the airflow is in the same direction as the rotation of the cylinder the maximum mass of fluid that can be supported on the cylinder is always less than that in classical coating flow, whereas when the circulation is in the opposite direction the maximum mass of fluid can be greater than that in classical coating flow.
Two introduced carnivores, the European red fox Vulpes vulpes and domestic cat Felis catus, have had extensive impacts on Australian biodiversity. In this study, we collate information on consumption of Australian birds by the fox, paralleling a recent study reporting on birds consumed by cats. We found records of consumption by foxes on 128 native bird species (18% of the non-vagrant bird fauna and 25% of those species within the fox’s range), a smaller tally than for cats (343 species, including 297 within the fox’s Australian range, a subset of that of the cat). Most (81%) bird species eaten by foxes are also eaten by cats, suggesting that predation impacts are compounded. As with consumption by cats, birds that nest or forage on the ground are most likely to be consumed by foxes. However, there is also some partitioning, with records of consumption by foxes but not cats for 25 bird species, indicating that impacts of the two predators may also be complementary. Bird species ≥3.4 kg were more likely to be eaten by foxes, and those <3.4 kg by cats. Our compilation provides an inventory and describes characteristics of Australian bird species known to be consumed by foxes, but we acknowledge that records of predation do not imply population-level impacts. Nonetheless, there is sufficient information from other studies to demonstrate that fox predation has significant impacts on the population viability of some Australian birds, especially larger birds, and those that nest or forage on the ground.
Motivated by the industrial manufacture of organic light-emitting-diode displays, we formulate and analyse a mathematical model for the evolution of a thin droplet in a shallow axisymmetric well of rather general shape both before and after touchdown that accounts for the spatially non-uniform evaporation of the fluid, perform physical experiments using three cylindrical wells with different small aspect ratios, and validate the mathematical model by comparing the present experimental results with the corresponding theoretical predictions for a cylindrical well.
The Cognitive Battery of the National Institutes of Health Toolbox (NIH-TB) is a collection of assessments that have been adapted and normed for administration across the lifespan and is increasingly used in large-scale population-level research. However, despite increasing adoption in longitudinal investigations of neurocognitive development, and growing recommendations that the Toolbox be used in clinical applications, little is known about the long-term temporal stability of the NIH-TB, particularly in youth.
Methods
The present study examined the long-term temporal reliability of the NIH-TB in a large cohort of youth (9–15 years-old) recruited across two data collection sites. Participants were invited to complete testing annually for 3 years.
Results
Reliability was generally low-to-moderate, with intraclass correlation coefficients ranging between 0.31 and 0.76 for the full sample. There were multiple significant differences between sites, with one site generally exhibiting stronger temporal stability than the other.
Conclusions
Reliability of the NIH-TB Cognitive Battery was lower than expected given early work examining shorter test-retest intervals. Moreover, there were very few instances of tests meeting stability requirements for use in research; none of the tests exhibited adequate reliability for use in clinical applications. Reliability is paramount to establishing the validity of the tool, thus the constructs assessed by the NIH-TB may vary over time in youth. We recommend further refinement of the NIH-TB Cognitive Battery and its norming procedures for children before further adoption as a neuropsychological assessment. We also urge researchers who have already employed the NIH-TB in their studies to interpret their results with caution.
An asymptotic model is derived for the competitive diffusion-limited evaporation of multiple thin sessile droplets under the assumption that the droplets are well separated. Exact solutions of the model are obtained for a pair of and for a polygonal array of identical droplets, and the model is found to perform well even outside its formal range of validity, up to and including the limit of touching droplets. The shielding effect of droplets on each other is demonstrated, and the model is used to investigate the effect of this shielding on droplet evolutions and lifetimes, as well as on the coffee-ring effect. The theoretical predictions of the model are found to be in good agreement with recent experimental results for seven relatively closely spaced droplets, suggesting that the model could be a useful tool for studying a wide range of other droplet configurations.
Objectives: Autobiographical memory dysfunction is a marker of vulnerability to depression. Patients with obstructive sleep apnea (OSA) experience high rates of depression and memory impairment, and autobiographical memory impairments have been observed compared to healthy controls; however, these groups were not age-matched. This study aimed to determine whether individuals with untreated OSA have impaired autobiographical memory when compared to age-matched controls, and to assess the quality of autobiographical memories from three broad time points. Methods: A total of 44 participants with OSA (M age=49.4±13.0) and 44 age-matched controls (M age=50.0±13.1) completed the Autobiographical Memory Interview (AMI) to assess semantic and episodic memories from three different life stages, and 44 OSA participants and 37 controls completed the Autobiographical Memory Test (AMT) to assess overgeneral memory recall (an inability to retrieve specific memories). Results: OSA participants had significantly poorer semantic recall of early adult life on the AMI (p<.001), and more overgeneral autobiographical memories recalled on the AMT (=.001), than controls. Poor semantic recall from early adult life was significantly correlated with more depressive symptoms (p=0.006) and lower education (p<0.02), while higher overgeneral memory recall was significantly associated with older age (p=.001). Conclusions: A specific deficit in semantic autobiographical recall was observed in individuals with OSA. OSA patients recalled more overgeneral memories, suggesting that aspects of the sleep disorder affect their ability to recollect specific details of events from their life. These cognitive features of OSA may contribute to the high incidence of depression in this population. (JINS 2019, 25, 266–274)
A naturally occurring hematitic iron oxide/layer-silicate complex has been found in red mottled patches of a deeply weathered granite in north-east Scotland. X-ray diffraction shows a basal spacing of 36 Å—also observable by high resolution electron microscopy—which expands to 40 Å with glycerol and contracts to 33·5 Å on heating. Selected area electron diffraction reveals a composite hematite/layer-silicate pattern with the a-axis of hematite parallel to the b-axis of the silicate. The IR spectrum of the complex clearly shows the contribution made by each of the components. The silicate, with bands due to OH stretching at 3602 cm−1, OH deformation at 855 cm−1, and Si-O stretching at 1085, 1035, 540 and 471 cm−1 resembles ferruginous pyrophyllite, while the hematite, with a perpendicular band at 647 cm−1, in-plane bands at 519, 438, 400, 302 and 227 cm−1 and a characteristic pattern of relative band intensities, is similar to a platy form of soil hematite. Electron microprobe analysis of individual particles gives the complex an (Fe + Al): Si ratio of 6:1, which is consistent with a structure made up of twelve octahedral sheets terminated on both sides by a silicate sheet. It seems likely that the complex developed from a siliceous ferrihydrite which became progressively more organized with geological time.
Formulated and technical grade HOE-39866 [ammonium-(3-amino-3-carboxypropyl) methylphosphinate] at concentrations of 10–1, 10–2, and 10–3M were applied to leaf blade tissues of nonreproductive adult redroot pigweed (Amaranthus retroflexus L. # AMARE) and fall panicum (Panicum dichotomiflorum Michx. # PANDI). Tissues were sampled at regular intervals after treatment and prepared for light microscopic examination. The major response of both species involved rupture and contortion of the interveinal mesophyll cells with concomitant disorganization of the bundle sheath cells. Rapid epidermal collapse occurred in redroot pigweed but not in fall panicum. The absence of adjuvants resulted in nonuniform symptom expression as herbicide droplets accumulated in depressions and along leaf margins. No other adjuvant-specific effect was observed. Herbicide concentration did not alter the final response but the time-to-expression increased as concentration decreased.
Roots of Canada thistle were excavated from the soil monthly from 1999 to 2001 near Scottsbluff, NE, to quantify the influence of changing soil temperature on free sugars and fructans in roots. Sucrose concentrations were low from May through August then increased in the fall and remained at high levels during winter and then declined in April as plants initiated spring growth. Changes in sucrose, 1-kestose (DP 3) and 1-nystose (DP 4) were shown to be closely associated with changes in soil temperature. During the second year of the study, average soil temperatures during the winter were colder than the first year and resulted in an increase of sucrose in Canada thistle roots. Experiments were conducted from 2001 to 2004 to determine whether there was a correlation between herbicide efficacy, time of herbicide application, and the resulting herbicide effect on root carbohydrate and Canada thistle control. Clopyralid applied in the fall reduced Canada thistle density 92% 8 months after treatment (MAT) whereas treatment made in the spring reduced plant density 33% 11 MAT. Fall application of clopyralid increased the activity of fructan 1-exohydrolase (1-FEH) in roots and was associated with a decline in sucrose, DP 4, and 1-fructofuranosyl-nystose (DP 5) 35 d after treatment (DAT). Spring application of clopyralid also resulted in a decrease of the same carbohydrates 35 DAT, but by 98 DAT, or early October, sucrose level in roots had recovered and was similar to nontreated plants. Fall application of 2,4-D or clopyralid reduced Canada thistle density 39 and 92% respectively, 8 MAT, but only clopyralid resulted in a reduction of sucrose, DP 4, DP 5, and total sugar and an increase of 1-FEH compared with nontreated plants.
A segment of the debate surrounding the commercialization of geneticallyengineered (GE) crops, such as glyphosate-resistant (GR) crops, focuses onthe theory that implementation of these traits is an extension of theintensification of agriculture that will further erode the biodiversity ofagricultural landscapes. A large field-scale study was conducted in 2006 inthe United States on 156 different field sites with a minimum 3-yr historyof GR corn, cotton, or soybean in the cropping system. The impact ofcropping system, crop rotation, frequency of using the GR crop trait, andseveral categorical variables on emerged weed density and diversity wasanalyzed. Species richness, evenness, Shannon's H′, proportion of forbs,erect growth habit, and C3 species diversity were all greater inagricultural sites that lacked crop rotation or were in a continuous GR cropsystem. Rotating between two GR crops (e.g., corn and soybean) or rotatingto a non-GR crop resulted in less weed diversity than a continuous GR crop.The composition of the weed flora was more strongly related to location(geography) than any other parameter. The diversity of weed flora inagricultural sites with a history of GR crop production can be influenced byseveral factors relating to the specific method in which the GR trait isintegrated (cropping system, crop rotation, GR trait rotation), the specificweed species, and the geographical location. The finding that fields withcontinuous GR crops demonstrated greater weed diversity is contrary toarguments opposing the use of GE crops. These results justify furtherresearch to clarify the complexities of crops grown withherbicide-resistance traits, or more broadly, GE crops, to provide a morecomplete characterization of their culture and local adaptation.
In 2010, a grower survey was administered to 1,299 growers in 22 states to determine changes in weed management in the United States from 2006 to 2009. The majority of growers had not changed weed management practices in the previous 3 yr; however, 75% reported using weed management practices targeted at glyphosate-resistant (GR) weeds. Growers were asked to rate their efforts at controlling GR weeds and rate the effectiveness of various practices for controlling/preventing GR weeds regardless of whether they were personally using them. Using the herbicide labeled rate, scouting fields, and rotating crops were among the practices considered by growers as most effective in managing GR weeds. Sixty-seven percent of growers reported effective management of GR weeds. Between the 2005 and 2010 Benchmark surveys, the frequency of growers using specific actions to manage GR weeds increased markedly. Although the relative effectiveness of practices, as perceived by growers, remained the same, the effectiveness rating of tillage and the use of residual and POST herbicides increased.
A telephone survey was conducted with growers in Iowa, Illinois, Indiana, Nebraska, Mississippi, and North Carolina to discern the utilization of the glyphosate-resistant (GR) trait in crop rotations, weed pressure, tillage practices, herbicide use, and perception of GR weeds. This paper focuses on survey results regarding herbicide decisions made during the 2005 cropping season. Less than 20% of the respondents made fall herbicide applications. The most frequently used herbicides for fall applications were 2,4-D and glyphosate, and these herbicides were also the most frequently used for preplant burndown weed control in the spring. Atrazine and acetochlor were frequently used in rotations containing GR corn. As expected, crop rotations using a GR crop had a high percentage of respondents that made one to three POST applications of glyphosate per year. GR corn, GR cotton, and non-GR crops had the highest percentage of growers applying non-glyphosate herbicides during the 2005 growing season. A crop rotation containing GR soybean had the greatest negative impact on non-glyphosate use. Overall, glyphosate use has continued to increase, with concomitant decreases in utilization of other herbicides.
Corn and soybean growers in Illinois, Indiana, Iowa, Mississippi, Nebraska, and North Carolina, as well as cotton growers in Mississippi and North Carolina, were surveyed about their views on changes in problematic weeds and weed pressure in cropping systems based on a glyphosate-resistant (GR) crop. No growers using a GR cropping system for more than 5 yr reported heavy weed pressure. Over all cropping systems investigated (continuous GR soybean, continuous GR cotton, GR corn/GR soybean, GR soybean/non-GR crop, and GR corn/non-GR crop), 0 to 7% of survey respondents reported greater weed pressure after implementing rotations using GR crops, whereas 31 to 57% felt weed pressure was similar and 36 to 70% indicated that weed pressure was less. Pigweed, morningglory, johnsongrass, ragweed, foxtail, and velvetleaf were mentioned as their most problematic weeds, depending on the state and cropping system. Systems using GR crops improved weed management compared with the technologies used before the adoption of GR crops. However, the long-term success of managing problematic weeds in GR cropping systems will require the development of multifaceted integrated weed management programs that include glyphosate as well as other weed management tactics.
A phone survey was administered to 1,195 growers in six states (Illinois, Indiana, Iowa, Mississippi, Nebraska, and North Carolina). The survey measured producers' crop history, perception of glyphosate-resistant (GR) weeds, past and present weed pressure, tillage practices, and herbicide use as affected by the adoption of GR crops. This article describes the changes in tillage practice reported in the survey. The adoption of a GR cropping system resulted in a large increase in the percentage of growers using no-till and reduced-till systems. Tillage intensity declined more in continuous GR cotton and GR soybean (45 and 23%, respectively) than in rotations that included GR corn or non-GR crops. Tillage intensity declined more in the states of Mississippi and North Carolina than in the other states, with 33% of the growers in these states shifting to more conservative tillage practices after the adoption of a GR crop. This was primarily due to the lower amount of conservation tillage adoption in these states before GR crop availability. Adoption rates of no-till and reduced-till systems increased as farm size decreased. Overall, producers in a crop rotation that included a GR crop shifted from a relatively more tillage-intense system to reduced-till or no-till systems after implementing a GR crop into their production system.
A segment of the debate surrounding the commercialization and use of glyphosate-resistant (GR) crops focuses on the theory that the implementation of these traits is an extension of the intensification of agriculture that will further erode the biodiversity of agricultural landscapes. A large field-scale study was initiated in 2006 in the United States on 156 different field sites with a minimum 3-yr history of GR-corn, -cotton or -soybean in the cropping system. The impact of cropping system, crop rotation, frequency of using the GR crop trait, and several categorical variables on seedbank weed population density and diversity was analyzed. The parameters of total weed population density of all species in the seedbank, species richness, Shannon's H′ and evenness were not affected by any management treatment. The similarity between the seedbank and aboveground weed community was more strongly related to location than management; previous year's crops and cropping systems were also important while GR trait rotation was not. The composition of the weed flora was more strongly related to location (geography) than any other parameter. The diversity of weed flora in agricultural sites with a history of GR crop production can be influenced by several factors relating to the specific method in which the GR trait is integrated (cropping system, crop rotation, GR trait rotation), the specific weed species, and the geographical location. Continuous GR crop, compared to fields with other cropping systems, only had greater species diversity (species richness) of some life forms, i.e., biennials, winter annuals, and prostrate weeds. Overall diversity was related to geography and not cropping system. These results justify further research to clarify the complexities of crops grown with herbicide-resistance traits to provide a more complete characterization of their culture and local adaptation to the weed seedbank.
Roots of dandelion were exhumed from the soil monthly from 1997 to 1999 near Scottsbluff, NE, to assess the seasonal changes in total sugars, glucose, fructose, sucrose, and fructans. In the spring, the initiation of plant growth was accompanied by increased fructose and, to a lesser degree, glucose as a percentage of total sugars. During June, July, and August, the percentage of total sugars with a middle to high degree of polymerization (DP) fructans increased. The DP in fructans changed with reduced rainfall and was associated with increased fructose and decreased high-DP fructans as a percentage of total sugars. Decreasing or freezing soil temperatures in the fall were associated with increased fructose and decreased high-DP fructans as a percentage of total sugars. When soil froze in December, the percentage of total sugars as sucrose and low-DP fructans increased and mid- to high-DP fructans decreased. The seasonal fluctuations of glucose, fructose, sucrose, and various fructan polymers may be one mechanism that allows dandelion to adapt to environmental stresses and gain a competitive advantage over other plants in the community. An understanding of these seasonal fluctuations in sugars may also allow better timing of biological, mechanical, and chemical control practices for improved plant management.