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Water hyacinth is a highly invasive aquatic species in the southern United States that requires intensive management through frequent herbicide applications. Quantifying management success in large-scale operations is challenging with traditional survey methods that rely on boat-based teams and can be time-consuming and labor-intensive. In contrast, an unmanned aerial system (UAS) allows a single operator to survey a waterbody more efficiently and rapidly, enhancing both coverage and data collection. Therefore, the objective of this research was to develop remote sensing techniques to assess herbicide efficacy for water hyacinth control in an outdoor mesocosm study. Experiments were conducted in spring and summer 2023 to compare and correlate data from visual evaluations of herbicide efficacy against nine vegetation indices (VIs) derived from UAS-based red-green-blue imagery. Penoxsulam, carfentrazone, diquat, 2,4-D, florpyrauxifen-benzyl, and glyphosate were applied at two rates, and experimental units were evaluated for 6 wk. The carotenoid reflectance index (CRI) had the highest Spearman’s correlation coefficient with visually evaluated efficacy for 2,4-D, diquat, and florpyrauxifen benzyl (> −0.77). The visible atmospherically resistance index (VARI) had the highest correlation with carfentrazone and penoxsulam treatments (> −0.70), and the excess greenness minus redness index had the highest correlation for glyphosate treatments (> −0.83). CRI had the highest correlation coefficient with the most herbicide treatments, and it was the only VI tested that did not include the red band. These VIs were satisfactory predictors of mid-range visually evaluated herbicide efficacy values but were poorly correlated with extremely low and high values, corresponding to nontreated and necrotic plants. Future research should focus on applying findings to real-world (nonexperimental) field conditions and testing imagery with spectral bands beyond the visible range.
Negative symptoms are a key feature of several psychiatric disorders. Difficulty identifying common neurobiological mechanisms that cut across diagnostic boundaries might result from equifinality (i.e., multiple mechanistic pathways to the same clinical profile), both within and across disorders. This study used a data-driven approach to identify unique subgroups of participants with distinct reward processing profiles to determine which profiles predicted negative symptoms.
Methods
Participants were a transdiagnostic sample of youth from a multisite study of psychosis risk, including 110 individuals at clinical high-risk for psychosis (CHR; meeting psychosis-risk syndrome criteria), 88 help-seeking participants who failed to meet CHR criteria and/or who presented with other psychiatric diagnoses, and a reference group of 66 healthy controls. Participants completed clinical interviews and behavioral tasks assessing four reward processing constructs indexed by the RDoC Positive Valence Systems: hedonic reactivity, reinforcement learning, value representation, and effort–cost computation.
Results
k-means cluster analysis of clinical participants identified three subgroups with distinct reward processing profiles, primarily characterized by: a value representation deficit (54%), a generalized reward processing deficit (17%), and a hedonic reactivity deficit (29%). Clusters did not differ in rates of clinical group membership or psychiatric diagnoses. Elevated negative symptoms were only present in the generalized deficit cluster, which also displayed greater functional impairment and higher psychosis conversion probability scores.
Conclusions
Contrary to the equifinality hypothesis, results suggested one global reward processing deficit pathway to negative symptoms independent of diagnostic classification. Assessment of reward processing profiles may have utility for individualized clinical prediction and treatment.
Identify risk factors for central line-associated bloodstream infections (CLABSI) in pediatric intensive care settings in an era with high focus on prevention measures.
Design:
Matched, case–control study.
Setting:
Quaternary children’s hospital.
Patients:
Cases had a CLABSI during an intensive care unit (ICU) stay between January 1, 2015 and December 31, 2020. Controls were matched 4:1 by ICU and admission date and did not develop a CLABSI.
Methods:
Multivariable, mixed-effects logistic regression.
Results:
129 cases were matched to 516 controls. Central venous catheter (CVC) maintenance bundle compliance was >70%. Independent CLABSI risk factors included administration of continuous non-opioid sedative (adjusted odds ratio (aOR) 2.96, 95% CI [1.16, 7.52], P = 0.023), number of days with one or more CVC in place (aOR 1.42 per 10 days [1.16, 1.74], P = 0.001), and the combination of a chronic CVC with administration of parenteral nutrition (aOR 4.82 [1.38, 16.9], P = 0.014). Variables independently associated with lower odds of CLABSI included CVC location in an upper extremity (aOR 0.16 [0.05, 0.55], P = 0.004); non-tunneled CVC (aOR 0.17 [0.04, 0.63], P = 0.008); presence of an endotracheal tube (aOR 0.21 [0.08, 0.6], P = 0.004), Foley catheter (aOR 0.3 [0.13, 0.68], P = 0.004); transport to radiology (aOR 0.31 [0.1, 0.94], P = 0.039); continuous neuromuscular blockade (aOR 0.29 [0.1, 0.86], P = 0.025); and administration of histamine H2 blocking medications (aOR 0.17 [0.06, 0.48], P = 0.001).
Conclusions:
Pediatric intensive care patients with chronic CVCs receiving parenteral nutrition, those on non-opioid sedative infusions, and those with more central line days are at increased risk for CLABSI despite current prevention measures.
We reviewed outcomes in all 36 consecutive children <5 kg supported with the Berlin Heart pulsatile ventricular assist device at the University of Florida, comparing those with acquired heart disease (n = 8) to those with congenital heart disease (CHD) (n = 28).
Methods:
The primary outcome was mortality. The Kaplan-Meier method and log-rank tests were used to assess group differences in long-term survival after ventricular assist device insertion. T-tests using estimated survival proportions were used to compare groups at specific time points.
Results:
Of 82 patients supported with the Berlin Heart at our institution, 49 (49/82 = 59.76%) weighed <10 kg and 36 (36/82 = 43.90%) weighed <5 kg. Of 36 patients <5 kg, 26 (26/36 = 72.22%) were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 36 patients <5 kg was [days]: median = 109, range = 4–305.) Eight out of 36 patients <5 kg had acquired heart disease, and all eight [8/8 = 100%] were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 8 patients <5 kg with acquired heart disease was [days]: median = 50, range = 9–130.) Twenty-eight of 36 patients <5 kg had congenital heart disease. Eighteen of these 28 [64.3%] were successfully bridged to transplantation. (The duration of support with ventricular assist device for these 28 patients <5 kg with congenital heart disease was [days]: median = 136, range = 4–305.) For all 36 patients who weighed <5 kg: 1-year survival estimate after ventricular assist device insertion = 62.7% (95% confidence interval = 48.5–81.2%) and 5-year survival estimate after ventricular assist device insertion = 58.5% (95% confidence interval = 43.8–78.3%). One-year survival after ventricular assist device insertion = 87.5% (95% confidence interval = 67.3–99.9%) in acquired heart disease and 55.6% (95% confidence interval = 39.5–78.2%) in CHD, P = 0.036. Five-year survival after ventricular assist device insertion = 87.5% (95% confidence interval = 67.3–99.9%) in acquired heart disease and 48.6% (95% confidence interval = 31.6–74.8%) in CHD, P = 0.014.
Conclusion:
Pulsatile ventricular assist device facilitates bridge to transplantation in neonates and infants weighing <5 kg; however, survival after ventricular assist device insertion in these small patients is less in those with CHD in comparison to those with acquired heart disease.
Hydrilla [Hydrilla verticillata (L. f.) Royle], an invasive aquatic weed, has had a rich introduction history into the United States, with multiple subspecies being introduced since the 1960s. The most recent occurred before 2016, when northern hydrilla (Hydrilla verticillata ssp. lithuanica) was discovered in the Connecticut River. By 2021, following a 3-yr survey from Agawam, MA, to the Long Island Sound by the Connecticut Agricultural Experiment Station Office of Aquatic Invasive Species, H. verticillata ssp. lithuanica was found in more than 113 km of the river, occupying 344 ha. Since this survey, there has been concern that H. verticillata ssp. lithuanica would spread to nearby waterbodies and have a significant negative impact. Here, we report the first documented spread and establishment of H. verticillata ssp. lithuanica from the Connecticut River to five waterbodies in Connecticut and one in Massachusetts. Of the eight sites where H. verticillata observations were made, 75% (n = 6) were confirmed to be H. verticillata ssp. lithuanica and 25% (n = 2) to be Hydrilla verticillata ssp. peregrina (wandering hydrilla). Except for one site, all six locations infested with H. verticillata ssp. lithuanica provide watercraft access through public or private boat ramps. The authors also postulate on the mechanisms facilitating the spread and establishment of this subspecies.
Although knowledge of their fossil record continues to improve, multituberculates nonetheless remain one of the more poorly understood mammalian clades, which can be attributed to a record comprised of isolated teeth and fragmentary jaws. Fortunately, the p4 of multituberculates is the most common form of remains for this group and is a principal source of diagnostic characters in systematic studies, the p4 of cimolodontan multituberculates is both common and a source of diagnostic characters in systematic studies. The results of a recent morphometric study on the neoplagiaulacid Mesodma suggest that p4 size may be more useful than shape in diagnosing the various species referred to this genus. We tested this hypothesis by applying two different morphometric methods (2D geometric morphometrics and linear measurements) to two samples: (1) one including the p4s of four known species of Mesodma (M. ambigua, M. thompsoni, M. formosa, and M. pygmaea), and (2) a sample of unidentified p4s of Mesodma from the Bug Creek Anthills locality of northeastern Montana. Our results indicate that while form explains most of the morphological variation in p4s of the various species of Mesodma, linear-measurement data support differences in p4 morphology that are not recovered by form data alone. Depending on the methods used, we found evidence for the presence of one or more species of Mesodma in the Bug Creek Anthills fauna. Although shape and size both contribute to morphological variation in the p4 of Mesodma, our results suggest that the diagnostic power of each varies with the type of methodology employed.
We identify a set of essential recent advances in climate change research with high policy relevance, across natural and social sciences: (1) looming inevitability and implications of overshooting the 1.5°C warming limit, (2) urgent need for a rapid and managed fossil fuel phase-out, (3) challenges for scaling carbon dioxide removal, (4) uncertainties regarding the future contribution of natural carbon sinks, (5) intertwinedness of the crises of biodiversity loss and climate change, (6) compound events, (7) mountain glacier loss, (8) human immobility in the face of climate risks, (9) adaptation justice, and (10) just transitions in food systems.
Technical summary
The Intergovernmental Panel on Climate Change Assessment Reports provides the scientific foundation for international climate negotiations and constitutes an unmatched resource for researchers. However, the assessment cycles take multiple years. As a contribution to cross- and interdisciplinary understanding of climate change across diverse research communities, we have streamlined an annual process to identify and synthesize significant research advances. We collected input from experts on various fields using an online questionnaire and prioritized a set of 10 key research insights with high policy relevance. This year, we focus on: (1) the looming overshoot of the 1.5°C warming limit, (2) the urgency of fossil fuel phase-out, (3) challenges to scale-up carbon dioxide removal, (4) uncertainties regarding future natural carbon sinks, (5) the need for joint governance of biodiversity loss and climate change, (6) advances in understanding compound events, (7) accelerated mountain glacier loss, (8) human immobility amidst climate risks, (9) adaptation justice, and (10) just transitions in food systems. We present a succinct account of these insights, reflect on their policy implications, and offer an integrated set of policy-relevant messages. This science synthesis and science communication effort is also the basis for a policy report contributing to elevate climate science every year in time for the United Nations Climate Change Conference.
Social media summary
We highlight recent and policy-relevant advances in climate change research – with input from more than 200 experts.
Knowledge graphs have become a common approach for knowledge representation. Yet, the application of graph methodology is elusive due to the sheer number and complexity of knowledge sources. In addition, semantic incompatibilities hinder efforts to harmonize and integrate across these diverse sources. As part of The Biomedical Translator Consortium, we have developed a knowledge graph–based question-answering system designed to augment human reasoning and accelerate translational scientific discovery: the Translator system. We have applied the Translator system to answer biomedical questions in the context of a broad array of diseases and syndromes, including Fanconi anemia, primary ciliary dyskinesia, multiple sclerosis, and others. A variety of collaborative approaches have been used to research and develop the Translator system. One recent approach involved the establishment of a monthly “Question-of-the-Month (QotM) Challenge” series. Herein, we describe the structure of the QotM Challenge; the six challenges that have been conducted to date on drug-induced liver injury, cannabidiol toxicity, coronavirus infection, diabetes, psoriatic arthritis, and ATP1A3-related phenotypes; the scientific insights that have been gleaned during the challenges; and the technical issues that were identified over the course of the challenges and that can now be addressed to foster further development of the prototype Translator system. We close with a discussion on Large Language Models such as ChatGPT and highlight differences between those models and the Translator system.
The U.S. Department of Agriculture–Agricultural Research Service (USDA-ARS) has been a leader in weed science research covering topics ranging from the development and use of integrated weed management (IWM) tactics to basic mechanistic studies, including biotic resistance of desirable plant communities and herbicide resistance. ARS weed scientists have worked in agricultural and natural ecosystems, including agronomic and horticultural crops, pastures, forests, wild lands, aquatic habitats, wetlands, and riparian areas. Through strong partnerships with academia, state agencies, private industry, and numerous federal programs, ARS weed scientists have made contributions to discoveries in the newest fields of robotics and genetics, as well as the traditional and fundamental subjects of weed–crop competition and physiology and integration of weed control tactics and practices. Weed science at ARS is often overshadowed by other research topics; thus, few are aware of the long history of ARS weed science and its important contributions. This review is the result of a symposium held at the Weed Science Society of America’s 62nd Annual Meeting in 2022 that included 10 separate presentations in a virtual Weed Science Webinar Series. The overarching themes of management tactics (IWM, biological control, and automation), basic mechanisms (competition, invasive plant genetics, and herbicide resistance), and ecosystem impacts (invasive plant spread, climate change, conservation, and restoration) represent core ARS weed science research that is dynamic and efficacious and has been a significant component of the agency’s national and international efforts. This review highlights current studies and future directions that exemplify the science and collaborative relationships both within and outside ARS. Given the constraints of weeds and invasive plants on all aspects of food, feed, and fiber systems, there is an acknowledged need to face new challenges, including agriculture and natural resources sustainability, economic resilience and reliability, and societal health and well-being.
With the aim of producing a 3D representation of tumors, imaging and molecular annotation of xenografts and tumors (IMAXT) uses a large variety of modalities in order to acquire tumor samples and produce a map of every cell in the tumor and its host environment. With the large volume and variety of data produced in the project, we developed automatic data workflows and analysis pipelines. We introduce a research methodology where scientists connect to a cloud environment to perform analysis close to where data are located, instead of bringing data to their local computers. Here, we present the data and analysis infrastructure, discuss the unique computational challenges and describe the analysis chains developed and deployed to generate molecularly annotated tumor models. Registration is achieved by use of a novel technique involving spherical fiducial marks that are visible in all imaging modalities used within IMAXT. The automatic pipelines are highly optimized and allow to obtain processed datasets several times quicker than current solutions narrowing the gap between data acquisition and scientific exploitation.
This study examined struggles to establish autonomy and relatedness with peers in adolescence and early adulthood as predictors of advanced epigenetic aging assessed at age 30. Participants (N = 154; 67 male and 87 female) were observed repeatedly, along with close friends and romantic partners, from ages 13 through 29. Observed difficulty establishing close friendships characterized by mutual autonomy and relatedness from ages 13 to 18, an interview-assessed attachment state of mind lacking autonomy and valuing of attachment at 24, and self-reported difficulties in social integration across adolescence and adulthood were all linked to greater epigenetic age at 30, after accounting for chronological age, gender, race, and income. Analyses assessing the unique and combined effects of these factors, along with lifetime history of cigarette smoking, indicated that each of these factors, except for adult social integration, contributed uniquely to explaining epigenetic age acceleration. Results are interpreted as evidence that the adolescent preoccupation with peer relationships may be highly functional given the relevance of such relationships to long-term physical outcomes.
The COVID-19 pandemic exacerbated gender disparities in some academic disciplines. This study examined the association of the pandemic with gender authorship disparities in clinical neuropsychology (CN) journals.
Method:
Author bylines of 1,018 initial manuscript submissions to four major CN journals from March 15 through September 15 of both 2019 and 2020 were coded for binary gender. Additionally, authorship of 40 articles published on pandemic-related topics (COVID-19, teleneuropsychology) across nine CN journals were coded for binary gender.
Results:
Initial submissions to these four CN journals increased during the pandemic (+27.2%), with comparable increases in total number of authors coded as either women (+23.0%) or men (+25.4%). Neither the average percentage of women on manuscript bylines nor the proportion of women who were lead and/or corresponding authors differed significantly across time. Moreover, the representation of women as authors of pandemic-related articles did not differ from expected frequencies in the field.
Conclusions:
Findings suggest that representation of women as authors of peer-reviewed manuscript submissions to some CN journals did not change during the initial months of the COVID-19 pandemic. Future studies might examine how risk and protective factors may have influenced individual differences in scientific productivity during the pandemic.
The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $\sim\!5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of $\sim\!162$ h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of $0.24\ \mathrm{mJy\ beam}^{-1}$ and angular resolution of $12-20$ arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.
Optical tracking systems typically trade off between astrometric precision and field of view. In this work, we showcase a networked approach to optical tracking using very wide field-of-view imagers that have relatively low astrometric precision on the scheduled OSIRIS-REx slingshot manoeuvre around Earth on 22 Sep 2017. As part of a trajectory designed to get OSIRIS-REx to NEO 101955 Bennu, this flyby event was viewed from 13 remote sensors spread across Australia and New Zealand to promote triangulatable observations. Each observatory in this portable network was constructed to be as lightweight and portable as possible, with hardware based off the successful design of the Desert Fireball Network. Over a 4-h collection window, we gathered 15 439 images of the night sky in the predicted direction of the OSIRIS-REx spacecraft. Using a specially developed streak detection and orbit determination data pipeline, we detected 2 090 line-of-sight observations. Our fitted orbit was determined to be within about 10 km of orbital telemetry along the observed 109 262 km length of OSIRIS-REx trajectory, and thus demonstrating the impressive capability of a networked approach to Space Surveillance and Tracking.
This study aimed to analyse social, health and environmental factors associated with the development of chronic otitis media by age nine.
Method
This was a prospective, longitudinal, birth cohort study of 6560 children, reviewed at age nine. Chronic otitis media defined as previous surgical history or video-otoscopic changes of tympanic membrane retraction, perforation or cholesteatoma. Non-affected children were used as the control group.
Results
Univariate analysis demonstrated an association between chronic otitis media and otorrhoea, snoring, grommet insertion, adenoidectomy, tonsillectomy, hearing loss, abnormal tympanograms and preterm birth. Multivariate analysis suggests many of these factors may be interrelated.
Conclusion
The association between chronic otitis media and otorrhoea, abnormal tympanograms and grommets supports the role of the Eustachian tube and otitis media (with effusion or acute) in the pathogenesis of chronic otitis media. The role of snoring, adenoidectomy and tonsillectomy is unclear. Associations suggested by previous studies (sex, socioeconomic group, parental smoking, maternal education, childcare, crowding and siblings) were not found to be significant predictors in this analysis.
This is the first report on the association between trauma exposure and depression from the Advancing Understanding of RecOvery afteR traumA(AURORA) multisite longitudinal study of adverse post-traumatic neuropsychiatric sequelae (APNS) among participants seeking emergency department (ED) treatment in the aftermath of a traumatic life experience.
Methods
We focus on participants presenting at EDs after a motor vehicle collision (MVC), which characterizes most AURORA participants, and examine associations of participant socio-demographics and MVC characteristics with 8-week depression as mediated through peritraumatic symptoms and 2-week depression.
Results
Eight-week depression prevalence was relatively high (27.8%) and associated with several MVC characteristics (being passenger v. driver; injuries to other people). Peritraumatic distress was associated with 2-week but not 8-week depression. Most of these associations held when controlling for peritraumatic symptoms and, to a lesser degree, depressive symptoms at 2-weeks post-trauma.
Conclusions
These observations, coupled with substantial variation in the relative strength of the mediating pathways across predictors, raises the possibility of diverse and potentially complex underlying biological and psychological processes that remain to be elucidated in more in-depth analyses of the rich and evolving AURORA database to find new targets for intervention and new tools for risk-based stratification following trauma exposure.
To institute facility-wide Kamishibai card (K-card) rounding for central venous catheter (CVC) maintenance bundle education and adherence and to evaluate its impact on bundle reliability and central-line–associated bloodstream infection (CLABSI) rates.
Design:
Quality improvement project.
Setting:
Inpatient units at a large, academic freestanding children’s hospital.
Participants:
Data for inpatients with a CVC in place for ≥1 day between November 1, 2017 and October 31, 2018 were included.
Intervention:
A K-card was developed based on 7 core elements in our CVC maintenance bundle. During monthly audits, auditors used the K-cards to ask bedside nurses standardized questions and to conduct medical record documentation reviews in real time. Adherence to every bundle element was required for the audit to be considered “adherent.” We recorded bundle reliability prospectively, and we compared reliability and CLABSI rates at baseline and 1 year after the intervention.
Results:
During the study period, 2,321 K-card audits were performed for 1,051 unique patients. Overall maintenance bundle reliability increased significantly from 43% at baseline to 78% at 12 months after implementation (P < .001). The hospital-wide CLABSI rate decreased from 1.35 during the 12-month baseline period to 1.17 during the 12-month intervention period, but the change was not statistically significant (incidence rate ratio [IRR], 0.87; 95% confidence interval [CI], 0.60–1.24; P = .41).
Conclusions:
Hospital-wide CVC K-card rounding facilitated standardized data collection, discussion of reliability, and real-time feedback to nurses. Maintenance bundle reliability increased after implementation, accompanied by a nonsignificant decrease in the CLABSI rate.
A new fossil site in a previously unexplored part of western Madagascar (the Beanka Protected Area) has yielded remains of many recently extinct vertebrates, including giant lemurs (Babakotia radofilai, Palaeopropithecus kelyus, Pachylemur sp., and Archaeolemur edwardsi), carnivores (Cryptoprocta spelea), the aardvark-like Plesiorycteropus sp., and giant ground cuckoos (Coua). Many of these represent considerable range extensions. Extant species that were extirpated from the region (e.g., Prolemur simus) are also present. Calibrated radiocarbon ages for 10 bones from extinct primates span the last three millennia. The largely undisturbed taphonomy of bone deposits supports the interpretation that many specimens fell in from a rock ledge above the entrance. Some primates and other mammals may have been prey items of avian predators, but human predation is also evident. Strontium isotope ratios (87Sr/86Sr) suggest that fossils were local to the area. Pottery sherds and bones of extinct and extant vertebrates with cut and chop marks indicate human activity in previous centuries. Scarcity of charcoal and human artifacts suggests only occasional visitation to the site by humans. The fossil assemblage from this site is unusual in that, while it contains many sloth lemurs, it lacks ratites, hippopotami, and crocodiles typical of nearly all other Holocene subfossil sites on Madagascar.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
This paper describes a model of electron energization and cyclotron-maser emission applicable to astrophysical magnetized collisionless shocks. It is motivated by the work of Begelman, Ergun and Rees [Astrophys. J. 625, 51 (2005)] who argued that the cyclotron-maser instability occurs in localized magnetized collisionless shocks such as those expected in blazar jets. We report on recent research carried out to investigate electron acceleration at collisionless shocks and maser radiation associated with the accelerated electrons. We describe how electrons accelerated by lower-hybrid waves at collisionless shocks generate cyclotron-maser radiation when the accelerated electrons move into regions of stronger magnetic fields. The electrons are accelerated along the magnetic field and magnetically compressed leading to the formation of an electron velocity distribution having a horseshoe shape due to conservation of the electron magnetic moment. Under certain conditions the horseshoe electron velocity distribution function is unstable to the cyclotron-maser instability [Bingham and Cairns, Phys. Plasmas 7, 3089 (2000); Melrose, Rev. Mod. Plasma Phys. 1, 5 (2017)].