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The understanding of the genetic basis of grain dormancy in wheat has rapidly improved in the last few years, and a number of genes have been identified related to that trait. We recently identified the wheat genes TaPM19-A1 and -A2 and we have now taken the first step towards understanding the role of this class of genes in seeds. By investigating the Arabidopsis homologous PM19-Like 1 (PM19L1) we have found that it has a seed-specific expression pattern and, while its expression is higher in dormant than in non-dormant seeds, knock-out mutations produced seeds with increased dormancy. Not only primary dormancy, but also secondary dormancy in response to high temperature was increased by the loss-of-function. We have also examined the function of PM19L1 by localizing the PM19 protein primarily to the cotyledon cells in seeds, possibly in membranes. By investigating the co-expression network of this gene we have found that it is connected to a small group of abscisic acid (ABA)-induced seed maturation and storage-related genes. The function of PM19L1 represents a good opportunity to explore the interactions of key factors that can influence seed dormancy such as ABA, temperature and membrane properties.
To assess the societal cost-effectiveness of the Transmural Trauma Care Model (TTCM), a multidisciplinary transmural rehabilitation model for trauma patients, compared with regular care.
The economic evaluation was performed alongside a before-and-after study, with a convenience control group measured only afterward, and a 9-month follow-up. Control group patients received regular care and were measured before implementation of the TTCM. Intervention group patients received the TTCM and were measured after its implementation. The primary outcome was generic health-related quality of life (HR-QOL). Secondary outcomes included disease-specific HR-QOL, pain, functional status, and perceived recovery.
Eighty-three trauma patients were included in the intervention group and fifty-seven in the control group. Total societal costs were lower in the intervention group than in the control group, but not statistically significantly so (EUR-267; 95 percent confidence interval [CI], EUR-4,175–3011). At 9 months, there was no statistically significant between-group differences in generic HR-QOL (0.05;95 percent CI, −0.02–0.12) and perceived recovery (0.09;95 percent CI, −0.09–0.28). However, mean between-group differences were statistically significantly in favor of the intervention group for disease-specific HR-QOL (−8.2;95 percent CI, −15.0–−1.4), pain (−0.84;95CI, −1.42–−0.26), and functional status (−20.1;95 percent CI, −29.6–−10.7). Cost-effectiveness acceptability curves indicated that if decision makers are not willing to pay anything per unit of effect gained, the TTCM has a 0.54–0.58 probability of being cost-effective compared with regular care. For all outcomes, this probability increased with increasing values of willingness-to-pay.
The TTCM may be cost-effective compared with regular care, depending on the decision-makers willingness to pay and the probability of cost-effectiveness that they perceive as acceptable.
Cognitive deficits in depressed adults may reflect impaired decision-making. To investigate this possibility, we analyzed data from unmedicated adults with Major Depressive Disorder (MDD) and healthy controls as they performed a probabilistic reward task. The Hierarchical Drift Diffusion Model (HDDM) was used to quantify decision-making mechanisms recruited by the task, to determine if any such mechanism was disrupted by depression.
Data came from two samples (Study 1: 258 MDD, 36 controls; Study 2: 23 MDD, 25 controls). On each trial, participants indicated which of two similar stimuli was presented; correct identifications were rewarded. Quantile-probability plots and the HDDM quantified the impact of MDD on response times (RT), speed of evidence accumulation (drift rate), and the width of decision thresholds, among other parameters.
RTs were more positively skewed in depressed v. healthy adults, and the HDDM revealed that drift rates were reduced—and decision thresholds were wider—in the MDD groups. This pattern suggests that depressed adults accumulated the evidence needed to make decisions more slowly than controls did.
Depressed adults responded slower than controls in both studies, and poorer performance led the MDD group to receive fewer rewards than controls in Study 1. These results did not reflect a sensorimotor deficit but were instead due to sluggish evidence accumulation. Thus, slowed decision-making—not slowed perception or response execution—caused the performance deficit in MDD. If these results generalize to other tasks, they may help explain the broad cognitive deficits seen in depression.
Rapid increases in herbicide resistance have highlighted the ability of weeds to undergo genetic change within a short period of time. That change, in turn, has resulted in an increasing emphasis in weed science on the evolutionary ecology and potential adaptation of weeds to herbicide selection. Here we argue that a similar emphasis would also be invaluable for understanding another challenge that will profoundly alter weed biology: the rapid rise in atmospheric carbon dioxide (CO2) and the associated changes in climate. Our review of the literature suggests that elevated CO2 and climate change will impose strong selection pressures on weeds and that weeds will often have the capacity to respond with rapid adaptive evolution. Based on current data, climate change and rising CO2 levels are likely to alter the evolution of agronomic and invasive weeds, with consequences for distribution, community composition, and herbicide efficacy. In addition, we identify four key areas that represent clear knowledge gaps in weed evolution: (1) differential herbicide resistance in response to a rapidly changing CO2/climate confluence; (2) shifts in the efficacy of biological constraints (e.g., pathogens) and resultant selection shifts in affected weed species; (3) climate-induced phenological shifts in weed distribution, demography, and fitness relative to crop systems; and (4) understanding and characterization of epigenetics and the differential expression of phenotypic plasticity versus evolutionary adaptation. These consequences, in turn, should be of fundamental interest to the weed science community.
The paper is related to an adaptive satellite communication system for data transmission from small, low cost, low Earth orbit satellites. Tests run in a set-up consisting of a number of software-defined radio (SDR) modules operating as a satellite, a ground station, and a satellite channel simulator, have shown that by changing modulation scheme and code rate one can obtain increase of amount of data which can be downloaded from a satellite during a single pass over a ground station approximately by a factor of 2. To determine data rates obtainable in an SDR system using a common personal computer as a digital signal processing device, execution times of particular processing steps involved in the reception process were measured.
A power MOSFET-based push–pull configuration nanosecond-pulse generator has been designed, constructed, and characterized to permeabilize cells for biological and medical applications. The generator can deliver pulses with durations ranging from 80 ns up to 1 µs and pulse amplitudes up to 1.4 kV. The unit has been tested for in vitro experiments on a medulloblastoma cell line. Following the exposure of cells to 100, 200, and 300 ns electric field pulses, permeabilization tests were carried out, and viability tests were conducted to verify the performance of the generator. The maximum temperature rise of the biological load was also calculated based on Joule heating energy conservation and experimental validation. Our results indicate that the developed device has good capabilities to achieve well-controlled electro-manipulation in vitro.
Introduction: When a patient is incapable of making medical decisions for themselves, choices are made according to the patient's previously expressed, wishes, values, and beliefs by a substitute decision maker (SDM). While interventions to engage patients in their own advance care planning exist, little is known about public readiness to act as a SDM on behalf of a loved one. This mixed-methods survey aimed to describe attitudes, enablers and barriers to preparedness to act as a SDM, and support for a population-level curriculum on the role of an SDM in end-of-life and resuscitative care. Methods: From November 2017 to June 2018, a mixed-methods street intercept survey was conducted in Ottawa, Canada. Descriptive statistics and logistic regression analysis were used to assess predictors of preparedness to be a SDM and understand support for a high school curriculum. Responses to open-ended questions were analyzed using inductive thematic analysis. Results: The 430 respondents were mostly female (56.5%) with an average age of 33.9. Although 73.0% of respondents felt prepared to be a SDM, 41.0% of those who reported preparedness never had a meaningful conversation with loved ones about their wishes in critical illness. The only predictors of SDM preparedness were the belief that one would be a future SDM (OR 2.36 95% CI 1.34-4.17), and age 50-64 compared to age 16-17 (OR 7.46 95% CI 1.25-44.51). Thematic enablers of preparedness included an understanding of a patient's wishes, the role of the SDM and strong familial relationships. Barriers included cultural norms, family conflict, and a need for time for high stakes decisions. Most respondents (71.9%) believed that 16 year olds should learn about SDMs. They noted age appropriateness, potential developmental and societal benefit, and improved decision making, while cautioning the need for a nuanced approach respectful of different maturity levels, cultures and individual experiences. Conclusion: This study reveals a concerning gap between perceived preparedness and actions taken in preparation to be an SDM for loved ones suffering critical illness. The results also highlight the potential role for high school education to address this gap. Future studies should further explore the themes identified to inform development of resources and curricula for improved health literacy in resuscitation and end-of-life care.
Innovation Concept: Transition to independent practice is challenging and early career physicians are more prone to burnout and error. Despite recommendations for formal mentorship to support physicians, only 43.6% of US academic Emergency Medicine departments have such programs. We describe an innovative mentorship program designed to support these early career physicians and enhance quality of care, career longevity, and wellness. We operationalized mentorship in which experienced, highly regarded, empathic mentors guide mentees in their personal and professional development. Methods: In this program two Emergency Physician mentors were teamed with each newly hired Emergency Physician. Mentees could request their own mentors, and teams were matched on the basis of shared personal and academic interests. Mentors received academic funding and training on good mentorship practice, roles and responsibilities, and feedback. Teams had to meet formally at least twice a year, with additional contact as needed. While mentees set the meeting agenda, teams were also encouraged to address four main areas. These areas were identified from a targeted needs assessment and literature review. They include: 1) clinical process and care, 2) departmental structure and culture, 3) teaching and scholarship, and 4) physician wellness. After meetings, mentees summarized and submitted the topics discussed and reflected on action plans. An oversight committee supported the program. Curriculum, Tool or Material: All nine (9) newly hired physicians joined the program in Fall 2018. As of December 2018, six (6) teams have had formal meetings. They discussed the following areas: clinical processes and care (50%), departmental structure and culture (100%), teaching and scholarship (67%), and physician wellness (100%). Other areas discussed include: academic career, financial planning, and networking. Teams spent 20-60% of the time formulating steps to achieve mentee career goals. They spent 40-60% of the time discussing skills and resources needed. End of year program evaluation will include outcomes such as satisfaction, value, effectiveness, projects, promotions, and awards. The results will shape future program design. Conclusion: We implemented a mentorship program for newly hired Emergency Physicians. As mentorship is integral to successful transition to independent practice, this program model could be highly beneficial to other academic Emergency Medicine departments.
Innovation Concept: Emergency medicine physicians must maintain a broad knowledge base and procedural skillset while fulfilling their academic roles as teachers, researchers and administrators. Most academic departments do not have a regular, affordable, formal continuing professional development (CPD) and faculty development (FD) curriculum for their staff. We set out to design and implement a novel continuous practice enhancement program to address this issue. Methods: Strategic planning by the Ottawa academic Department of EM identified CPD and FD as priorities. A program was created to support high quality, monthly CPD/FD courses provided by physicians. We had 5 goals: (1) enhance clinical and academic skills, (2) disseminate group best practices, (3) sustain skills in high impact/low frequency scenarios, (4) support physician academic careers, and (5) acquire new procedural skills. A CPD/FD Committee composed of local meded experts and experienced clinical teachers was tasked with overseeing the creation and evaluation of these sessions. Curriculum, Tool or Material: The longitudinal curriculum was informed by perceived needs (group survey), ascribed needs (M&M rounds, physician metrics and departmental leadership priorities) and participant feedback. The committee identified local experts to present on their areas of expertise in order to promote group best practice. Topics to-date have included clinical skills updates, teaching and coaching strategies and academic career planning. A comprehensive monthly simulation-based curriculum was rolled out simultaneously to give participants the opportunity to develop crisis resource management and critical care skills. Except for sessions requiring advanced equipment or cadavers, sessions are financed by academic funds and free for participants. Conclusion: Faculty academic learning and engagement is an important goal and participation in this curriculum is reviewed at each physician's annual reappointment. To-date, 18 physicians (21% of our group) have presented topics and 92% of physicians have participated in at least one session with 63% having attended three or more. Evaluations have been overwhelmingly positive, and a recent survey identified the CPD/FD program as a significant contributor to our physicians’ wellness. We introduced an innovative, structured CPD/FD program in response to perceived and ascribed needs of our physicians and departmental leadership. Our successful CPD/FD curriculum represents a model for other departments who are considering similar initiatives.
Novel designs of a circularly polarized 2 × 2 and 4 × 4 slot array antennas (CPSAAs) are proposed. Sequential phase feed network composed of a section of 270° and four strips is utilized to feed the array structures. Array elements are simple linearly polarized wide slot antennas (WSAs) composed of simple radiating patches with truncation on four corners and slotted ground plane on substrate backside. Each WSA operates over the UWB frequency band of 3.1–10.6 GHz. When the WSAs are arranged in the form of 2 × 2 and 4 × 4 CPSAAs, frequency bands of 3–13.1 and 1.4–12.3 GHz are covered, respectively. More importantly, CP is generated at 4.5–8 and 4.6–8.8 GHz for 2 × 2 and 4 × 4 CPSAAs, respectively. This is while; the WSAs are linearly polarized elements. Higher gain values and wider bandwidths are obtained with respect to single WSA. Design process and performance analysis of the single and array antennas are discussed through the paper.
Despite established clinical associations among major depression (MD), alcohol dependence (AD), and alcohol consumption (AC), the nature of the causal relationship between them is not completely understood. We leveraged genome-wide data from the Psychiatric Genomics Consortium (PGC) and UK Biobank to test for the presence of shared genetic mechanisms and causal relationships among MD, AD, and AC.
Linkage disequilibrium score regression and Mendelian randomization (MR) were performed using genome-wide data from the PGC (MD: 135 458 cases and 344 901 controls; AD: 10 206 cases and 28 480 controls) and UK Biobank (AC-frequency: 438 308 individuals; AC-quantity: 307 098 individuals).
Positive genetic correlation was observed between MD and AD (rgMD−AD = + 0.47, P = 6.6 × 10−10). AC-quantity showed positive genetic correlation with both AD (rgAD−AC quantity = + 0.75, P = 1.8 × 10−14) and MD (rgMD−AC quantity = + 0.14, P = 2.9 × 10−7), while there was negative correlation of AC-frequency with MD (rgMD−AC frequency = −0.17, P = 1.5 × 10−10) and a non-significant result with AD. MR analyses confirmed the presence of pleiotropy among these four traits. However, the MD-AD results reflect a mediated-pleiotropy mechanism (i.e. causal relationship) with an effect of MD on AD (beta = 0.28, P = 1.29 × 10−6). There was no evidence for reverse causation.
This study supports a causal role for genetic liability of MD on AD based on genetic datasets including thousands of individuals. Understanding mechanisms underlying MD-AD comorbidity addresses important public health concerns and has the potential to facilitate prevention and intervention efforts.
Surgery for CHD has been slow to develop in parts of the former Soviet Union. The impact of an 8-year surgical assistance programme between an emerging centre and a multi-disciplinary international team that comprised healthcare professionals from developed cardiac programmes is analysed and presented.
Material and methods
The international paediatric assistance programme included five main components – intermittent clinical visits to the site annually, medical education, biomedical engineering support, nurse empowerment, and team-based practice development. Data were analysed from visiting teams and local databases before and since commencement of assistance in 2007 (era A: 2000–2007; era B: 2008–2015). The following variables were compared between periods: annual case volume, operative mortality, case complexity based on Risk Adjustment for Congenital Heart Surgery (RACHS-1), and RACHS-adjusted standardised mortality ratio.
A total of 154 RACHS-classifiable operations were performed during era A, with a mean annual case volume by local surgeons of 19.3 at 95% confidence interval 14.3–24.2, with an operative mortality of 4.6% and a standardised mortality ratio of 2.1. In era B, surgical volume increased to a mean of 103.1 annual cases (95% confidence interval 69.1–137.2, p<0.0001). There was a non-significant (p=0.84) increase in operative mortality (5.7%), but a decrease in standardised mortality ratio (1.2) owing to an increase in case complexity. In era B, the proportion of local surgeon-led surgeries during visits from the international team increased from 0% (0/27) in 2008 to 98% (58/59) in the final year of analysis.
The model of assistance described in this report led to improved adjusted mortality, increased case volume, complexity, and independent operating skills.
In their attempts to define the poetic style of John Donne and his followers, twentieth-century critics have often considered its relationship to analogous movements in the continental literatures. They have seen in the common love of paradox and in the common use of far-fetched metaphors, or conceits, links which unite Donne and the other English metaphysical poets to Marino and his followers in Italy and to Góngora and his followers in Spain. Credit for the original insight connecting Donne and Marino, as is so often the case with original insights, must go to Dr. Johnson, who in the famous passage on the metaphysical poets in his “Life of Cowley” suggested that the metaphysical style was “borrowed from Marino and his followers”.
Watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] grafting is commonly used for management of diseases caused by soilborne pathogens; however, little research exists describing the effect of grafting on the weed-competitive ability of watermelon. Field experiments determined the response in yield, fruit number, and fruit quality of grafted and nongrafted watermelon exposed to increasing densities of Palmer amaranth (Amaranthus palmeri S. Watson). Grafting treatments included ‘Exclamation’ triploid (seedless) watermelon grafted on two interspecific hybrid squash rootstocks ‘Carnivor’ and ‘Kazako’, with nongrafted Exclamation as the control. Weed treatments included A. palmeri at densities of 1, 2, 3, and 4 A. palmeri plants per watermelon planting hole (0.76-m row) and a weed-free control. Increasing A. palmeri densities caused significant reductions (P <0.05) in marketable watermelon yield and marketable fruit number. Watermelon yield reduction was described by a rectangular hyperbola model, and 4 A. palmeri plants planting hole−1 reduced marketable yield 41%, 38%, and 65% for Exclamation, Carnivor, and Kazako, respectively. Neither grafting treatment nor A. palmeri density had a biologically meaningful effect on soluble solids content or on the incidence of hollow heart in watermelon fruit. Amaranthus palmeri seed and biomass production was similar across weed population densities, but seed number per female A. palmeri decreased according to a two-parameter exponential decay equation. Thus, increasing weed population densities resulted in increased intraspecific competition among A. palmeri plants. While grafting may offer benefits for disease resistance, no benefits regarding weed-competitive ability were observed, and a consistent yield penalty was associated with grafting, even in weed-free treatments.
Field experiments determined the critical period for weed control (CPWC) in grafted and nongrafted watermelon [Citrullus lanatus (Thumb.) Matsum. & Nakai] grown in plasticulture. Transplant types included ‘Exclamation’ seedless watermelon as the nongrafted control as well as Exclamation grafted onto two interspecific hybrid squash (ISH) rootstocks, ‘Carnivor’ and ‘Kazako’. To simulate weed emergence throughout the season, establishment treatments (EST) consisted of two seedlings each of common purslane (Portulaca oleracea L.), large crabgrass [Digitaria sanguinalis (L.) Scop.], and yellow nutsedge (Cyperus esculentus L.) transplanted in a 15 by 15 cm square centered on watermelon plants at 0, 2, 3, 4, and 6 wk after watermelon transplanting (WATr) and remained until the final watermelon harvest at 11 WATr. To simulate weed control at different times in the season, removal treatments (REM) consisted of two seedlings of the same weed species transplanted in a 15 by 15 cm square centered on watermelon plants on the same day of watermelon transplanting and allowed to remain until 2, 3, 4, 6, and 11 WATr, at which time they were removed. Season-long weedy and weed-free controls were included for both EST and REM studies in both years. For all transplant types, aboveground biomass of weeds decreased as weed establishment was delayed and increased as weed removal was delayed. The predicted CPWC for nongrafted Exclamation and Carnivor required only a single weed removal between 2.3 and 2.5 WATr and 1.9 and 2.6 WATr, respectively, while predicted CPWC for Kazako rootstock occurred from 0.3 to 2.6 WATr. Our study results suggest that weed control for this mixed population of weeds would be similar between nongrafted Exclamation and Exclamation grafted onto Carnivor. But the observed CPWC of Exclamation grafted onto Kazako suggests that CPWC may vary with specific rootstock–scion combinations.
This study examined changes in adolescents’ perceived relationship quality with mothers and fathers from middle school to high school, gender differences, and associated mental health consequences using longitudinal data from the New England Study of Suburban Youth cohort (n = 262, 48% female) with annual assessments (Grades 6–12). For both parents, alienation increased, and trust and communication decreased from middle school to high school, with greater changes among girls. Overall, closeness to mothers was higher than with fathers. Girls, compared to boys, perceived more trust and communication and similar levels of alienation with mothers at Grade 6. Girls perceived stronger increases in alienation from both parents and stronger declines in trust with mothers during middle school. Increasing alienation from both parents and less trust with mothers at Grade 6 was associated with higher levels of anxiety at Grade 12. Less trust with both parents at Grade 6 and increasing alienation and decreasing trust with mothers in high school were associated with higher levels of depressive symptoms at Grade 12. Overall, girls reported having higher levels of anxiety at Grade 12 compared to boys. Findings on the course of the quality of parent–adolescent relationships over time are discussed in terms of implications for more targeted research and interventions.
Internal gravity wave energy contributes significantly to the energy budget of the oceans, affecting mixing and the thermohaline circulation. Hence it is important to determine the internal wave energy flux
is the pressure perturbation field and
is the velocity perturbation field. However, the pressure perturbation field is not directly accessible in laboratory or field observations. Previously, a Green’s function based method was developed to calculate the instantaneous energy flux field from a measured density perturbation field
, given a constant buoyancy frequency
. Here we present methods for computing the instantaneous energy flux
for an internal wave field with vertically varying background
, as in the oceans where
typically decreases by two orders of magnitude from the pycnocline to the deep ocean. Analytic methods are presented for computing
from a density perturbation field for
varying linearly with
. To generalize this approach to arbitrary
, we present a computational method for obtaining
. The results for
for the different cases agree well with results from direct numerical simulations of the Navier–Stokes equations. Our computational method can be applied to any density perturbation data using the MATLAB graphical user interface ‘EnergyFlux’.
Traits of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are strongly associated in children and adolescents, largely due to genetic factors. Less is known about the phenotypic and aetiological overlap between ADHD and ASD traits in adults.
We studied 6866 individuals aged 20–28 years from the Swedish Study of Young Adult Twins. Inattention (IA) and hyperactivity/impulsivity (HI) were assessed using the WHO Adult ADHD Self-Report Scale-V1.1. Repetitive and restricted behaviours (RRB) and social interaction and communication (SIC) were assessed using the Autism-Tics, ADHD, and other Comorbidities inventory. We used structural equation modelling to decompose covariance between these ADHD and ASD trait dimensions into genetic and shared/non-shared environmental components.
At the phenotypic level, IA was similarly correlated with RRB (r = 0.33; 95% Confidence Interval (CI) 0.31–0.36) and with SIC (r = 0.32; 95% CI 0.29–0.34), whereas HI was more strongly associated with RRB (r = 0.38; 95% CI 0.35–0.40) than with SIC (r = 0.24; 95% CI 0.21–0.26). Genetic and non-shared environmental effects accounted for similar proportions of the phenotypic correlations, whereas shared environmental effects were of minimal importance. The highest genetic correlation was between HI and RRB (r = 0.56; 95% 0.46–0.65), and the lowest was between HI and SIC (r = 0.33; 95% CI 0.23–0.43).
We found evidence for dimension-specific phenotypic and aetiological overlap between ADHD and ASD traits in adults. Future studies investigating mechanisms underlying comorbidity between ADHD and ASD may benefit from exploring several symptom-dimensions, rather than considering only broad diagnostic categories.