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Six on-farm studies determined the effects of a rolled rye cover crop, herbicide program, and planting technique on cotton stand, weed control, and cotton yield in Georgia. Treatments included: (1) rye drilled broadcast with 19-cm row spacing and a broadcast-herbicide program (2) rye drilled with a 25-cm rye-free zone in the cotton row and a broadcast-herbicide program (3) rye drilled with a 25-cm rye-free zone in the cotton row with PPI and PRE herbicides banded in the cotton planting row, and (4) no cover crop (i.e., weedy cover) with broadcast herbicides. At two locations, cotton stand was lowest with rye drilled broadcast; at these sites the rye-free zone maximized stand equal to the no-cover system. At a third location, cover crop systems resulted in greater stand, due to enhanced soil moisture preservation compared with the no-cover system. Treatments did not influence cotton stand at the other three locations and did not differ in the control of weeds other than Palmer amaranth at any location. Treatments controlled Palmer amaranth equally at three locations; however, differences were observed at the three locations having the greatest glyphosate-resistant plant densities. For these locations, when broadcasting herbicides, Palmer amaranth populations were reduced 82% to 86% in the broadcast rye and rye-free zone systems compared with the no-cover system at harvest. The system with banded herbicides was nearly 21 times less effective than the similar system broadcasting herbicides. At these locations, yields in the rye broadcast and rye-free zone systems with broadcast herbicides were increased 9% to 16% compared with systems with no cover or a rye-free zone with PPI and PRE herbicides banded. A rolled rye cover crop can lessen weed emergence and selection pressure while improving weed control and cotton yield, but herbicides should be broadcast in fields heavily infested with glyphosate-resistant Palmer amaranth.
Chemical bonding in native oxides of GaAs, before and after etching, is detected by X-Ray Photoelectron Spectroscopy (XPS). It is correlated with surface energy engineering (SEE), measured via Three Liquid Contact Angle Analysis (3LCAA), and oxygen coverage, measured by High Resolution Ion Beam Analysis (HR-IBA).
Before etching, GaAs native oxides are found to be hydrophobic with an average surface energy, γT, of 33 ± 1 mJ/m2, as measured by 3LCAA. After dilute NH4OH etching, GaAs becomes highly hydrophilic and its surface energy, γT, increases by a factor 2 to a reproducible value of 66 ± 1 mJ/m2. Using HR-IBA, oxygen coverage on GaAs is found to decrease from 7.2 ± 0.5 monolayers (ML) to 3.6 ± 0.5 ML. The 1.17 ratio of Ga to As, measured by HR-IBA, remains constant after etching.
XPS is used to measure oxidation of Ga and As, as well as surface stoichiometry on two locations of several GaAs(100) wafers before and after etching. The relative proportions of Ga and As are unaffected by adventitious carbon contamination. The 1.16 Ga:As ratio, measured by XPS, matches HR-IBA analysis. The proportions of oxidized Ga and As do not change significantly after etching. However, the initial ratio of As2O5 to As2O3, within the oxidized As, significantly decreases after etching from approximately 3:1 to 3:2.
Absolute oxygen coverage, as a function of surface processing, is determined within 0.5 ML by HR-IBA. XPS offers insight into these modifications by detecting electronic states and phase composition changes of GaAs oxides. The changes in surface chemistry are correlated to changes in hydro-affinity and surface energies measured by 3LCAA.
The aggregation of neurocognitive deficits among the non-psychotic first-degree relatives of adult- and childhood-onset schizophrenia patients suggests that there may be a common etiology for these deficits in childhood- and adult-onset illness. However, there is considerable heterogeneity in the presentation of neurobiological abnormalities, and whether there are differences in the extent of familial transmission for specific domains of cognitive function has not been systematically addressed.
We employed variance components analysis, as implemented in SOLAR-Eclipse, to evaluate the evidence of familial transmission for empirically derived composite scores representing attention, working memory, verbal learning, verbal retention, and memory for faces. We contrast estimates for adult- and childhood-onset schizophrenia families and matched community control pedigrees, and compare our findings to previous reports based on analogous neurocognitive assessments.
We observed varying degrees of familial transmission; attention and working memory yielded comparable, significant estimates for adult-onset and community control pedigrees; verbal learning was significant for childhood-onset and community control pedigrees; and facial memory demonstrated significant familial transmission only for childhood-onset schizophrenia. Model-fitting analyses indicated significant differences in familiality between adult- and childhood-onset schizophrenia for attention, working memory, and verbal learning.
By comprehensively assessing a wide range of neurocognitive domains in adult- and childhood-onset schizophrenia families, we provide additional support for specific neurocognitive domains as schizophrenia endophenotypes. Whereas comparable estimates of familial transmission for certain dimensions of cognitive functioning support a shared etiology of adult- and childhood-onset neurocognitive function, observed differences may be taken as preliminary evidence of partially divergent multifactorial architectures.
Apolipoprotein E (APOE) E4 is the main genetic risk factor for Alzheimer’s disease (AD). Due to the consistent association, there is interest as to whether E4 influences the risk of other neurodegenerative diseases. Further, there is a constant search for other genetic biomarkers contributing to these phenotypes, such as microtubule-associated protein tau (MAPT) haplotypes. Here, participants from the Ontario Neurodegenerative Disease Research Initiative were genotyped to investigate whether the APOE E4 allele or MAPT H1 haplotype are associated with five neurodegenerative diseases: (1) AD and mild cognitive impairment (MCI), (2) amyotrophic lateral sclerosis, (3) frontotemporal dementia (FTD), (4) Parkinson’s disease, and (5) vascular cognitive impairment.
Genotypes were defined for their respective APOE allele and MAPT haplotype calls for each participant, and logistic regression analyses were performed to identify the associations with the presentations of neurodegenerative diseases.
Our work confirmed the association of the E4 allele with a dose-dependent increased presentation of AD, and an association between the E4 allele alone and MCI; however, the other four diseases were not associated with E4. Further, the APOE E2 allele was associated with decreased presentation of both AD and MCI. No associations were identified between MAPT haplotype and the neurodegenerative disease cohorts; but following subtyping of the FTD cohort, the H1 haplotype was significantly associated with progressive supranuclear palsy.
This is the first study to concurrently analyze the association of APOE isoforms and MAPT haplotypes with five neurodegenerative diseases using consistent enrollment criteria and broad phenotypic analysis.
All Fire and Emergency Services (FES) personnel must balance FES work with their other responsibilities. Given that women tend to take on a greater responsibility for management of household/domestic activities than men, the on-call component of their FES work may be associated with very different challenges. Despite this, women have rarely been the focus of on-call research.
To explore women’s on-call experiences in the FES by examining coping styles and strategies, with the goal of helping to innovate the way women are supported in FES roles.
Relevant findings from two studies are included. The first study involved FES personnel from two agencies in Australia (n=24) who participated in a semi-structured interview. The second study was an anonymous online survey to determine work characteristics, sleep, stress, and coping in on-call workers more broadly, with workers from all industries across Australia (n=228) invited to participate.
Interview data identified two major themes in terms of coping with on-call work. Support (from family, social, and work), planning, and preparation were identified as important in helping women cope in the context of on-call unpredictability. Results from the survey (43% women) showed that on-call workers were an engaged group in terms of their coping, with 67% classified as having a positive coping style and 58% of women indicating that they agreed/strongly agreed with the statement, “I cope well with on-call work.”
Taken together, these data highlight engagement with positive coping by women who do on-call work, including in the FES. Importantly, positive coping strategies, such as talking about emotions, problem-solving, and seeking support have been linked to increased shift work tolerance in other populations. Coping style and strategies represent modifiable variables which could be specifically applied to assist women to manage the unique challenges associated with on-call work in the FES.
Introduction: Formal ultrasound imaging, with use of ultrasound technicians and radiologists, provides a valuable diagnostic component to patient care in the Emergency Department (ED). Outside of regular weekday hours, ordering formal ultrasounds can produce logistical difficulties. EDs have developed protocols for next-day ultrasounds, where the patient returns the following day for imaging and reassessment by an ED physician. This creates additional stress on ED resources – personnel, bed space, finances – that are already strained. There is a dearth of literature regarding the use of next-day ultrasounds or guidelines to direct efficient use. This study sought to accumulate data on the use of ED next-day ultrasounds and patient oriented clinical outcomes. Methods: This study was a retrospective chart review of 150 patients, 75 from each of two different tertiary care hospitals in Saskatoon, Saskatchewan. After a predetermined start date, convenience samples were collected of all patients who had undergone a next-day ultrasound ordered from the ED until the quota was satisfied. Patients were identified by an electronic medical record search for specific triage note phrases indicating use of next-day ultrasounds. Different demographic, clinical, and administrative parameters were collected and analyzed. Results: Of the 150 patients, the mean age was 35.9 years and 75.3% were female. Median length of stay for the first visit was 4.1 hours, and 2.2 hours for the return visit. Most common ultrasound scans performed were abdomen and pelvis/gyne (34.7%), complete abdomen (30.0%), duplex extremity venous (10.0%). Most common indications on the ultrasound requisition were nonspecific abdominal pain (18.7%), vaginal bleeding with or without pregnancy (17.3%), and hepatobiliary pathology (15.3%). Ultrasounds results reported a relevant finding 56% of the time, and 34% were completely normal. After the next-day ultrasound 5.3% of patients had a CT scan, 10.7% had specialist consultation, 8.2% were admitted, and 7.3% underwent surgery. Conclusion: Information was gathered to close gaps in knowledge about the use of next-day ultrasounds from the ED. A large proportion of patients are discharged home without further interventions. Additional research and the development of next-day ultrasound guidelines or outpatient pathways may improve patient care and ED resource utilization.
Objectives: Studies of neurocognitively elite older adults, termed SuperAgers, have identified clinical predictors and neurobiological indicators of resilience against age-related neurocognitive decline. Despite rising rates of older persons living with HIV (PLWH), SuperAging (SA) in PLWH remains undefined. We aimed to establish neuropsychological criteria for SA in PLWH and examined clinically relevant correlates of SA. Methods: 734 PLWH and 123 HIV-uninfected participants between 50 and 64 years of age underwent neuropsychological and neuromedical evaluations. SA was defined as demographically corrected (i.e., sex, race/ethnicity, education) global neurocognitive performance within normal range for 25-year-olds. Remaining participants were labeled cognitively normal (CN) or impaired (CI) based on actual age. Chi-square and analysis of variance tests examined HIV group differences on neurocognitive status and demographics. Within PLWH, neurocognitive status differences were tested on HIV disease characteristics, medical comorbidities, and everyday functioning. Multinomial logistic regression explored independent predictors of neurocognitive status. Results: Neurocognitive status rates and demographic characteristics differed between PLWH (SA=17%; CN=38%; CI=45%) and HIV-uninfected participants (SA=35%; CN=55%; CI=11%). In PLWH, neurocognitive groups were comparable on demographic and HIV disease characteristics. Younger age, higher verbal IQ, absence of diabetes, fewer depressive symptoms, and lifetime cannabis use disorder increased likelihood of SA. SA reported increased independence in everyday functioning, employment, and health-related quality of life than non-SA. Conclusions: Despite combined neurological risk of aging and HIV, youthful neurocognitive performance is possible for older PLWH. SA relates to improved real-world functioning and may be better explained by cognitive reserve and maintenance of cardiometabolic and mental health than HIV disease severity. Future research investigating biomarker and lifestyle (e.g., physical activity) correlates of SA may help identify modifiable neuroprotective factors against HIV-related neurobiological aging. (JINS, 2019, 25, 507–519)
Synchrotron radiation was used to obtain a high-resolution powder diffraction pattern of the high-density form of BeH2, a material whose unit-cell dimensions have not previously been determined. The observed d-spacing values were presented to three different computer indexing programs. All three programs returned as best solution a body-centered orthorhombic unit cell with a = 9.082, b = 4.160, c = 7.707 Å and V = 292 Å3. Interpretation of the three-dimensional Patterson led to 12 BeH2 molecules per unit cell; thus, the theoretical density is 0.755 g/cm3. The molecular structure is based on a network of corner-sharing BeH4 tetrahedra rather than flat, infinite chains with hydrogen bridges previously assumed.
The real-time x-ray powder diffractometer control system AUTO incorporates several advances in data collection and analysis. Counting procedures for selected area data collection are optimized to achieve either a preselected statistical error in minimum time or a minimum error in fixed total time. Run files are employed to greatly simplify quantitative analysis procedures and for controlling repetitive runs. External calibration curves for 20 are used to eliminate all but sample dependent aberrations to peak positions. A generalized data file structure is used to document the instrumental variables and sample parameters.
Over the past fifteen years two basic computer search/match strategies have evolved. The exhaustive search approach of Johnson and Vand (1) uses a sequential file structure whereas Nichols (2) developed a strategy which uses an inverted file, examining only those patterns containing lines of interest. Frevel (3) was the first to attempt to relate the quality of the reference patterns to the search strategy using a very restricted data base. These “first generation” search/match algorithms were forced to use very wide d and I windows due to the poor quality of the unknown and reference patterns.
Snyder (4) wrote the first “second generation” search/match procedure which takes advantage of high quality of data in the JCPDS data base when it is present. Recently, a minicomputer optimized version of the Johnson-Vand strategy has been incorporated into this search system enabling a chance to compare these two strategies under similar conditions.
An X-ray diffraction system is under development for remote analysis of lunar rocks from an unmanned, soft-landed spacecraft. The objective of this experiment is the identification of rock-forming phases and estimation of their abundances, compositions, and other data which are indicative of the nature of genetic processes on the moon. A 2:1 scanning parafocusing geometry was successfully miniaturized for this purpose by W. Pavrish, and a complete diffraction system, based on the design is in preparation. The diffract ometer including high-voltage power supply weighs 18 lb, occupies 0.9 ft3, and requires 56 W of continuous power. A sample acquisition and preparation system will be an integral part of the diffractometer. Diffraction analyses of a rhyolite, basalt, and chondritic meteorite are given as examples of the capabilities and limitations of rock analysis by this method.
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.
Posttraumatic stress disorder (PTSD) is associated with higher risk of incident hypertension, but it is unclear whether specific aspects of PTSD are particularly cardiotoxic. PTSD is a heterogeneous disorder, comprising dimensions of fear and dysphoria. Because elevated fear after trauma may promote autonomic nervous system dysregulation, we hypothesized fear would predict hypertension onset, and associations with hypertension would be stronger with fear than dysphoria.
We examined fear and dysphoria symptom dimensions in relation to incident hypertension over 24 years in 2709 trauma-exposed women in the Nurses’ Health Study II. Posttraumatic fear and dysphoria symptom scores were derived from a PTSD diagnostic interview. We used proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for each symptom dimension (quintiles) with new-onset hypertension events (N = 925), using separate models. We also considered lower-order symptom dimensions of fear and dysphoria.
Higher levels of fear (P-trend = 0.02), but not dysphoria (P-trend = 0.22), symptoms were significantly associated with increased hypertension risk after adjusting for socio-demographics and family history of hypertension. Women in the highest v. lowest fear quintile had a 26% higher rate of developing hypertension [HR = 1.26 (95% CI 1.02–1.57)]; the increased incidence associated with greater fear was similar when further adjusted for biomedical and health behavior covariates (P-trend = 0.04) and dysphoria symptoms (P-trend = 0.04). Lower-order symptom dimension analyses provided preliminary evidence that the re-experiencing and avoidance components of fear were particularly associated with hypertension.
Fear symptoms associated with PTSD may be a critical driver of elevated cardiovascular risk in trauma-exposed individuals.
Annually dated tree-rings of 509 live and deadwood limber pine (Pinus flexilis) samples from the semi-arid Wassuk Range, Nevada, yielded a 3996-yr record extending from 1983 BC to AD 2013. Correlations of radial growth with climate were positive for water relations and negative for summer temperatures. Long-term trends of ring-width corresponded to climate variability documented from other proxies, including low growth during the Late Holocene Dry Period and Medieval Climate Anomaly (MCA) and elevated growth during cool, wet periods of the Neoglacial and Little Ice Age. Spline fit of the data indicated that growth decrease in the last 20 years was second lowest on record, surpassed by lowest growth at 20 BC—AD 150. Demographics of limber pine by aspect and elevation were not strongly related to long-term climate dynamics, except in the case of extirpations on all but north aspects at the end of the MCA. Pines occurred persistently on north aspects, where a continuous record existed to present. Elevation shifts were not obvious on any aspect, and no evidence existed for migration above current treeline. Non-climatic factors appear to interact with climate to make north slopes refugial for upland pines in semi-arid regions across four millennia.
The objective of this WSSA Weed Loss Committee report is to provide quantitative data on the potential yield loss in sugar beet due to weed interference from the major sugar beet growing areas of the United States and Canada. Researchers and extension specialists who conducted research on weed control in sugar beet in the United States and Canada provided quantitative data on sugar beet yield loss due to weed interference in their regions. Specifically, data were requested from weed control studies in sugar beet from up to 10 individual studies per calendar year over a 15-yr period between 2002 and 2017. Data collected indicated that if weeds are left uncontrolled under optimal agronomic practices, growers in Idaho, Michigan, Minnesota, Montana, Nebraska, North Dakota, Ontario, Oregon, and Wyoming would potentially lose an average of 79%, 61%, 66%, 68%, 63%, 75%, 83%, 78%, and 77% of the sugar beet yield. The corresponding monetary loss would be approximately US$234, US$122, US$369, US$43, US$40, US$211, US$12, US$14, and US$32 million, respectively. The average yield loss due to weed interference for the primary sugar beet growing areas of North America was estimated to be 70%. Thus, if weeds are not controlled, growers in the United States would lose approximately 22.4 million tonnes of sugar beet yield valued at approximately US$1.25 billion, and growers in Canada would lose approximately 0.5 million tonnes of sugar beet yield valued at approximately US$25 million. The high return on investment in weed management highlights the importance of continued weed science research for sustaining high crop yield and profitability of sugar beet production in North America.
Abnormal thyroid function is prevalent among women and has been linked to increased risk of chronic disease. Posttraumatic stress disorder (PTSD) has been linked to thyroid dysfunction in some studies; however, the results have been inconsistent. Thus, we evaluated trauma exposure and PTSD symptoms in relation to incident thyroid dysfunction in a large longitudinal cohort of civilian women.
We used data from 45 992 women from the ongoing Nurses’ Health Study II, a longitudinal US cohort study that began in 1989. In 2008, history of trauma and PTSD were assessed with the Short Screening Scale for Diagnostic and Statistical Manual of Mental Disorders, fourth edition, PTSD, and incident thyroid dysfunction was determined by participants’ self-report in biennial questionnaires of physician-diagnosed hypothyroidism and Graves’ hyperthyroidism. The study period was from 1989 to 2013. Proportional hazard models were used to estimate multivariable-adjusted hazard ratios and 95% confidence intervals (CIs) for incident hypothyroidism and Graves’ hyperthyroidism.
In multivariable-adjusted models, we found significant associations for PTSD only with hypothyroidism [p-trend <0.001; trauma with no PTSD symptoms, 1.08 (95% CI 1.02–1.15); 1–3 PTSD symptoms, 1.12 (95% CI 1.04–1.21); 4–5 PTSD symptoms, 1.23 (95% CI 1.13–1.34); and 6–7 PTSD symptoms, 1.26 (95% CI 1.14–1.40)]. PTSD was not associated with risk of Graves’ hyperthyroidism (p-trend = 0.34). Associations were similar in sensitivity analyses restricted to outcomes with onset after 2008, when PTSD was assessed.
PTSD was associated with higher risk of hypothyroidism in a dose-dependent fashion. Highlighted awareness for thyroid dysfunction may be especially important in women with PTSD.
SNP in the vitamin D receptor (VDR) gene is associated with risk of lower respiratory infections. The influence of genetic variation in the vitamin D pathway resulting in susceptibility to upper respiratory infections (URI) has not been investigated. We evaluated the influence of thirty-three SNP in eleven vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4, CYP27A1, LRP2, CUBN and VDR) resulting in URI risk in 725 adults in London, UK, using an additive model with adjustment for potential confounders and correction for multiple comparisons. Significant associations in this cohort were investigated in a validation cohort of 737 children in Manchester, UK. In all, three SNP in VDR (rs4334089, rs11568820 and rs7970314) and one SNP in CYP3A4 (rs2740574) were associated with risk of URI in the discovery cohort after adjusting for potential confounders and correcting for multiple comparisons (adjusted incidence rate ratio per additional minor allele ≥1·15, Pfor trend ≤0·030). This association was replicated for rs4334089 in the validation cohort (Pfor trend=0·048) but not for rs11568820, rs7970314 or rs2740574. Carriage of the minor allele of the rs4334089 SNP in VDR was associated with increased susceptibility to URI in children and adult cohorts in the United Kingdom.
In 785 mother–child (50% male) pairs from a longitudinal epidemiological birth cohort, we investigated associations between inflammation-related epigenetic polygenic risk scores (i-ePGS), environmental exposures, cognitive function, and child and adolescent internalizing and externalizing problems. We examined prenatal and postnatal effects. For externalizing problems, one prenatal effect was found: i-ePGS at birth associated with higher externalizing problems (ages 7–15) indirectly through lower cognitive function (age 7). For internalizing problems, we identified two effects. For a prenatal effect, i-ePGS at birth associated with higher internalizing symptoms via continuity in i-ePGS at age 7. For a postnatal effect, higher postnatal adversity exposure (birth through age 7) associated with higher internalizing problems (ages 7–15) via higher i-ePGS (age 7). Hence, externalizing problems were related mainly to prenatal effects involving lower cognitive function, whereas internalizing problems appeared related to both prenatal and postnatal effects. The present study supports a link between i-ePGS and child and adolescent mental health.