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We study the bendocapillary instability of a liquid droplet that part fills a flexible walled channel. Inspired by experiments in which a periodic pattern emerges as droplets of liquid are condensed slowly into deformable microchannels, we develop a mathematical model of this instability. We describe equilibria of the system, and use a combination of numerical methods and asymptotic analysis in the limit of small channel wall deflections, to elucidate the key features of this instability. We find that configurations are unstable to perturbations of sufficiently small wavenumber regardless of parameter values, that the growth rate of the instability is highly sensitive to the volume of liquid in the channel, and that both wetting and non-wetting configurations are susceptible to the instability in the same channel. Insight into novel interfacial instabilities opens the possibility for their control and thus exploitation in processes such as microfabrication.
Plasma jets are widely investigated both in the laboratory and in nature. Astrophysical objects such as black holes, active galactic nuclei and young stellar objects commonly emit plasma jets in various forms. With the availability of data from plasma jet experiments resembling astrophysical plasma jets, classification of such data would potentially aid in not only investigating the underlying physics of the experiments but also the study of astrophysical jets. In this work we use deep learning to process all of the laboratory plasma images from the Caltech Spheromak Experiment spanning two decades. We found that cosine similarity can aid in feature selection, classify images through comparison of feature vector direction and be used as a loss function for the training of AlexNet for plasma image classification. We also develop a simple vector direction comparison algorithm for binary and multi-class classification. Using our algorithm we demonstrate 93 % accurate binary classification to distinguish unstable columns from stable columns and 92 % accurate five-way classification of a small, labelled data set which includes three classes corresponding to varying levels of kink instability.
Posttraumatic Stress Disorder (PTSD) tends to co-occur with greater alcohol consumption as well as alcohol use disorder (AUD). However, it is unknown whether the same etiologic factors that underlie PTSD-alcohol-related problems comorbidity also contribute to PTSD- alcohol consumption.
Methods
We used summary statistics from large-scale genome-wide association studies (GWAS) of European-ancestry (EA) and African-ancestry (AA) participants to estimate genetic correlations between PTSD and a range of alcohol consumption-related and alcohol-related problems phenotypes.
Results
In EAs, there were positive genetic correlations between PTSD phenotypes and alcohol-related problems phenotypes (e.g. Alcohol Use Disorders Identification Test (AUDIT) problem score) (rGs: 0.132−0.533, all FDR adjusted p < 0.05). However, the genetic correlations between PTSD phenotypes and alcohol consumption -related phenotypes (e.g. drinks per week) were negatively associated or non-significant (rGs: −0.417 to −0.042, FDR adjusted p: <0.05-NS). For AAs, the direction of correlations was sometimes consistent and sometimes inconsistent with that in EAs, and the ranges were larger (rGs for alcohol-related problems: −0.275 to 0.266, FDR adjusted p: NS, alcohol consumption-related: 0.145–0.699, FDR adjusted p: NS).
Conclusions
These findings illustrate that the genetic associations between consumption and problem alcohol phenotypes and PTSD differ in both strength and direction. Thus, the genetic factors that may lead someone to develop PTSD and high levels of alcohol consumption are not the same as those that lead someone to develop PTSD and alcohol-related problems. Discussion around needing improved methods to better estimate heritabilities and genetic correlations in diverse and admixed ancestry samples is provided.
The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors.
Method
Online questionnaires were administered to 34 465 individuals (aged 16 years or above) in April/May 2020 in the UK, recruited from existing cohorts or via social media. Around one-third (n = 12 718) of included participants had prior diagnoses of depression or anxiety and had completed pre-pandemic mental health assessments (between September 2018 and February 2020), allowing prospective investigation of symptom change.
Results
Prospective symptom analyses showed small decreases in depression (PHQ-9: −0.43 points) and anxiety [generalised anxiety disorder scale – 7 items (GAD)-7: −0.33 points] and increases in PTSD (PCL-6: 0.22 points). Conversely, retrospective symptom analyses demonstrated significant large increases (PHQ-9: 2.40; GAD-7 = 1.97), with 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Across both prospective and retrospective measures of symptom change, worsening depression, anxiety and PTSD symptoms were associated with prior mental health diagnoses, female gender, young age and unemployed/student status.
Conclusions
We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias-related underestimation of prior symptom severity.
Current dam discharge patterns in Noxon Rapids Reservoir reduce concentration and exposure times (CET) of herbicides used for aquatic plant management. Herbicide applications during periods of low dam discharge may increase herbicide CETs and improve efficacy. Applications of rhodamine WT dye were monitored under peak (736 to 765 m3 s−1) and minimum (1.4 to 2.8 m3 s−1) dam discharge patterns to quantify water-exchange processes. Whole-plot dye half-life under minimal discharge was 33 h, a 15-fold increase compared with the dye treatment during peak discharge. Triclopyr concentrations measured during minimum discharge within the treated plot ranged from 214 ± 25 to 1,243 ± 36 µg L−1 from 0 to 48 h after treatment (HAT), respectively. Endothall concentrations measured during minimum discharge in the same plot ranged from 164 ± 78 to 2,195 ± 1,043 µg L−1 from 0 to 48 HAT, respectively. Eurasian watermilfoil (Myriophyllum spicatum L.) occurrence in the treatment plot was 66%, 8%, and 14% during pretreatment, 5 wk after treatment (WAT), and 52 WAT, respectively. Myriophyllum spicatum occurrence in the nontreated plot was 68%, 71%, and 83% during pretreatment, 5 WAT, and 52 WAT, respectively. Curlyleaf pondweed (Potamogeton crispus L.) occurrence in the treatment plot was 29%, 0%, and 97% during pretreatment, 5 WAT, and 52 WAT, respectively. Potamogeton crispus increased from 24% to 83% at 0 WAT to 52 WAT, respectively, in the nontreated plot. Native species richness declined from 3.3 species per point to 2.1 in the treatment plot in the year of treatment but returned to pretreatment numbers by 52 WAT. Native species richness did not change during the study in the nontreated reference plot. Herbicide applications during periods of low flow can increase CETs and improve control, whereas applications during times of high-water flow would shorten CETs and could result in reduced treatment efficacy.
Maintaining Mg status may be important for military recruits, a population that experiences high rates of stress fracture during initial military training (IMT). The objectives of this secondary analysis were to (1) compare dietary Mg intake and serum Mg in female and male recruits pre- and post-IMT, (2) determine whether serum Mg was related to parameters of bone health pre-IMT, and (3) whether Ca and vitamin D supplementation (Ca/vitamin D) during IMT modified serum Mg. Females (n 62) and males (n 51) consumed 2000 mg of Ca and 25 μg of vitamin D/d or placebo during IMT (12 weeks). Dietary Mg intakes were estimated using FFQ, serum Mg was assessed and peripheral quantitative computed tomography was performed on the tibia. Dietary Mg intakes for females and males pre-IMT were below the estimated average requirement and did not change with training. Serum Mg increased during IMT in females (0·06 ± 0·08 mmol/l) compared with males (–0·02 ± 0·10 mmol/l; P < 0·001) and in those consuming Ca/vitamin D (0·05 ± 0·09 mmol/l) compared with placebo (0·001 ± 0·11 mmol/l; P = 0·015). In females, serum Mg was associated with total bone mineral content (BMC, β = 0·367, P = 0·004) and robustness (β = 0·393, P = 0·006) at the distal 4 % site, stress–strain index of the polaris axis (β = 0·334, P = 0·009) and robustness (β = 0·420, P = 0·004) at the 14 % diaphyseal site, and BMC (β = 0·309, P = 0·009) and stress–strain index of the polaris axis (β = 0·314, P = 0·006) at the 66 % diaphyseal site pre-IMT. No significant relationships between serum Mg and bone measures were observed in males. Findings suggest that serum Mg may be modulated by Ca/vitamin D intake and may impact tibial bone health during training in female military recruits.
Among older people with cognitive impairment and mild dementia, relatively little is known about the factors that predict preferences for everyday living activities and experiences and that influence the relative importance of those activities and experiences.
Design:
Cross-sectional study.
Setting:
Participants were recruited from the Massachusetts Alzheimer’s Disease Research Center (MADRC) Clinical Core longitudinal cohort.
Participants:
The sample included 62 community-dwelling older adults with cognitive impairment (Clinical Dementia Rating global score ≥ 0.5).
Measurements:
We used the Preferences for Everyday Living Inventory (PELI) to assess preferences for activities and lifestyle experiences among persons with cognitive impairment. Within-subjects analysis of variance was used to test for significant differences in the mean ratings of importance for four domains of the PELI (“autonomous choice,” “social engagement,” “personal growth,” and “keeping a routine”). Multiple regression models were used to relate predictors, including neuropsychiatric symptoms, to importance ratings for each domain.
Results:
Significant differences were noted in the mean importance ratings of the preferences domains: “social engagement” preferences were rated as most important, followed by “autonomous choice,” “personal growth,” and “keeping a routine.” For the “social engagement” preferences domain, female sex was significantly associated with higher importance of “social engagement,” while depressive symptoms (Geriatric Depression Scale-15 scores) were significantly associated with lower importance.
Conclusions:
This study adds novel insight into the everyday preferences of community-dwelling older adults with cognitive impairment and highlights the impact of a number of factors, particularly level of depression, on how important various everyday experiences are perceived.
Clinical assessments are a primary method for ascertaining suicide risk, yet the language used across measures is inconsistent. The implications of these discrepancies for adolescent responding are unknown, which is troubling as multiple research areas (i.e. on culture, mental health language, and suicide communication) indicate individuals from varying sociodemographic backgrounds may communicate differently regarding mental health concerns. The aims of the current study are to investigate whether a geographically diverse sample of adolescents respond differently to directly and indirectly phrased suicide attempt questions (i.e. directly phrased includes the term ‘suicide’ and indirectly asks about suicidal behavior without using ‘suicide’), and to examine whether sociodemographic factors and history of mental health service usage relate to endorsement differences.
Methods
Participants were N = 5909 adolescents drawn from the Emergency Department Screening for Teens at Risk for Suicide multi-site study. The lifetime suicide attempt was assessed with two items from an adapted version of the Columbia Suicide Severity Rating Scale (C-SSRS; Posner et al., 2008): (1) a directly phrased question asking about ‘suicide attempts’ and (2) an indirectly phrased question providing the definition of an attempt.
Results
An adolescent majority (83.7%) consistently reported no lifetime suicide attempt across items, 10.1% consistently reported one or more lifetime attempts across items, and 6.2% of adolescents responded discordantly to the items.
Conclusions
Multivariable models indicated multiple demographic and mental health service variables significantly predicted discordant responding, with a notable finding being that father/stepfather education level at or below high school education predicted endorsing only the direct question.
Psychological stress is associated with accelerated cellular aging and increased risk for aging-related diseases, but the underlying molecular mechanisms are unclear.
Methods
We examined the effect of stress on a DNA methylation age predictor that was shown to correlate strongly with chronological age across human tissues (Horvath 2013). Genome-wide DNA methylation was measured in peripheral blood using the 450K Illumina array in three independent cohorts: the Grady Trauma Project/GTP (N=366); a panic disorder case/control sample recruited at the Max Planck Institute of Psychiatry/MPI-P (N=318); and the Conte Center for the Psychobiology of Early-Life Trauma/Conte (N=42). Age acceleration was calculated by subtracting chronological age from age predicted by DNA methylation. Psychiatric symptomatology and stressors were assessed using standard questionnaires.
Results
DNA methylation age strongly correlated with chronological age in all samples (r=0.9, p=2.5x10<sup>-133</sup>). Cumulative lifetime stress but not childhood or current stress predicted age acceleration in GTP (p=0.012) and MPI-P (p=0.021). Moreover, epigenetic age acceleration predicted depression (GTP: p=0.002; Conte: p=0.014) and panic disorder (p=0.007). In secondary analyses, we examined the effect of lifetime stress on individual CpGs of the DNA methylation age predictor. After correcting for multiple comparisons, we identified in both GTP and MPI-P a stress-regulated CpG near MCAM, a gene implicated in aging-related diseases, including cardiovascular disease and cancers.
Conclusions
Cumulative lifetime stress, but not childhood or current stress, and psychiatric phenotypes are associated with accelerated epigenetic aging. Our findings may explain the accelerated cellular aging and increased disease risk associated with chronic stress and psychiatric disorders.
Aberration-corrected STEM has become a standard analytical technique in the field of nanoscience. As “designer materials” have become more in demand in academic circles, verification of a desired product makes atomic-resolutionanalysis mandatory. Industry currently faces the same trend where tailor-made materials are customized for a given application. Here we show several examples where quantifiable atomic-scale manipulation of nanomaterials can have a dramatic impact on structure and, by extension, functionality.
Children with hypoplastic left heart syndrome are at a risk for neurodevelopmental delays. Current guidelines recommend systematic evaluation and management of neurodevelopmental outcomes with referral for early intervention services. The Single Ventricle Reconstruction Trial represents the largest cohort of children with hypoplastic left heart syndrome ever assembled. Data on life events and resource utilisation have been collected annually. We sought to determine the type and prevalence of early intervention services used from age 1 to 4 years and factors associated with utilisation of services.
Methods
Data from 14-month neurodevelopmental assessment and annual medical history forms were used. We assessed the impact of social risk and geographic differences. Fisher exact tests and logistic regression were used to evaluate associations.
Results
Annual medical history forms were available for 302 of 314 children. Greater than half of the children (52–69%) were not receiving services at any age assessed, whereas 20–32% were receiving two or more therapies each year. Utilisation was significantly lower in year 4 (31%) compared with years 1–3 (with a range from 40 to 48%) (p<0.001). Social risk factors were not associated with the use of services at any age but there were significant geographic differences. Significant delay was reported by parents in 18–43% of children at ages 3 and 4.
Conclusion
Despite significant neurodevelopmental delays, early intervention service utilisation was low in this cohort. As survival has improved for children with hypoplastic left heart syndrome, attention must shift to strategies to optimise developmental outcomes, including enrolment in early intervention when merited.
We sought to comprehensively assess the prevalence and outcomes of complications associated with Staphylococcus aureus bacteremia (SAB) in children. Secondarily, prevalence of methicillin resistance and outcomes of complications from methicillin-resistant S. aureus (MRSA) vs. methicillin-susceptible S. aureus SAB were assessed. This is a single-center cross-sectional study of 376 patients ⩽18 years old with SAB in 1990–2014. Overall, 197 (52%) patients experienced complications, the most common being osteomyelitis (33%), skin and soft tissue infection (31%), and pneumonia (25%). Patients with complications were older (median 3 vs. 0·7 years, P = 0·05) and more had community-associated SAB (66% vs. 34%, P = 0·001). Fewer patients with complications had a SAB-related emergency department or hospital readmission (10% vs. 19%, P = 0·014). Prevalence of methicillin resistance increased from 1990–1999 to 2000–2009, but decreased in 2010–2014. Complicated MRSA bacteremia resulted in more intensive care unit admissions (66% vs. 47%, P = 0·03) and led to increased likelihood of having ⩾2 foci (58% vs. 26%, P < 0·001). From multivariate analysis, community-associated SAB increased risk and concurrent infections decreased risk of complications (odds ratio (OR) 1·82 (1·1–3·02), P = 0·021) and (OR 0·58 (0·34–0·97), P = 0·038), respectively. In conclusion, children with SAB should be carefully evaluated for complications. Methicillin resistance remains associated with poor outcomes but have decreased in overall prevalence.
Absorption of 14C-imazaquin by leaves of field-grown flue-cured tobacco was similar when applied to young seedlings immediately after transplanting or to plants 3 wk after transplanting. The distribution of 14C in treated leaves indicated that 40% was absorbed, 54% remained in water extracts of leaf surfaces, and 6% was found in the epicuticular wax layer 8 d after treatment. Translocation of the herbicide from treated leaves to roots was very low (4 to 5%). In contrast, soil applications of imazaquin and subsequent uptake by roots resulted in retention of 40 to 53% in roots and translocation of 47 to 60% to shoots after 8 d. Analyses of methanol-soluble extracts of 14C indicated that more than 77% of the foliar-applied herbicide was metabolized in roots and upper shoots after 2 d. Similarly, 64% or more of the imazaquin was degraded in roots and shoots 2 d after root absorption.
Imazaquin {2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinolinecarboxylic acid} was evaluated in the field for weed control in flue-cured tobacco (Nicotiana tabacum L.) during 1983 and 1984. The 75 DG formulation of imazaquin was used at 0.28 and 0.42 kg ai/ha. Methods of application were: preplant incorporated, over the top immediately after transplanting, postbed incorporated, and early postemergence. Imazaquin controlled 90%, or better, of common lambsquarters (Chenopodium album L. # CHEAL), common ragweed (Ambrosia artemisiifolia L. # AMBEL), redroot pigweed (Amaranthus retroflexus L. # AMARE), spiny amaranth (Amaranthus spinosus L. # AMASP), ivyleaf morningglory [Ipomoea hederacea (L.) Jacq. # IPOHE], sicklepod (Cassia obtusifolia L. # CASOB), and prickly sida (Sida spinosa L. # SIDSP) with all application methods except early postemergence. It controlled 80 to 89% of large crabgrass (Digitaria sanguinalis L. # DIGSA) by the soil-applied methods. Postemergence applications of imazaquin controlled common ragweed, pigweed spp., ivyleaf morningglory, prickly sida, and sicklepod. Imazaquin was less effective postemergence on lambsquarters and large crabgrass. Tobacco tolerated use of imazaquin by all methods of application except preplant incorporation.
Herbicide-resistant Amaranthus spp. continue to cause management difficulties in soybean. New soybean technologies under development, including resistance to various combinations of glyphosate, glufosinate, dicamba, 2,4-D, isoxaflutole, and mesotrione, will make possible the use of additional herbicide sites of action in soybean than is currently available. When this research was conducted, these soybean traits were still regulated and testing herbicide programs with the appropriate soybean genetics in a single experiment was not feasible. Therefore, the effectiveness of various herbicide programs (PRE herbicides followed by POST herbicides) was evaluated in bare-ground experiments on glyphosate-resistant Palmer amaranth and glyphosate-resistant waterhemp (both tall and common) at locations in Arkansas, Illinois, Indiana, Missouri, Nebraska, and Tennessee. Twenty-five herbicide programs were evaluated; 5 of which were PRE herbicides only, 10 were PRE herbicides followed by POST herbicides 3 to 4 wks after (WA) the PRE application (EPOST), and 10 were PRE herbicides followed by POST herbicides 6 to 7 WA the PRE application (LPOST). Programs with EPOST herbicides provided 94% or greater control of Palmer amaranth and waterhemp at 3 to 4 WA the EPOST. Overall, programs with LPOST herbicides resulted in a period of weed emergence in which weeds would typically compete with a crop. Weeds were not completely controlled with the LPOST herbicides because weed sizes were larger (≥ 15 cm) compared with their sizes at the EPOST application (≤ 7 cm). Most programs with LPOST herbicides provided 80 to 95% control at 3 to 4 WA applied LPOST. Based on an orthogonal contrast, using a synthetic-auxin herbicide LPOST improves control of Palmer amaranth and waterhemp over programs not containing a synthetic-auxin LPOST. These results show herbicides that can be used in soybean and that contain auxinic- or HPPD-resistant traits will provide growers with an opportunity for better control of glyphosate-resistant Palmer amaranth and waterhemp over a wide range of geographies and environments.