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The systems ecology paradigm (SEP) emerged in the late 1960s at a time when societies throughout the world were beginning to recognize that our environment and natural resources were being threatened by their activities. Management practices in rangelands, forests, agricultural lands, wetlands, and waterways were inadequate to meet the challenges of deteriorating environments, many of which were caused by the practices themselves. Scientists recognized an immediate need was developing a knowledge base about how ecosystems function. That effort took nearly two decades (1980s) and concluded with the acceptance that humans were components of ecosystems, not just controllers and manipulators of lands and waters. While ecosystem science was being developed, management options based on ecosystem science were shifting dramatically toward practices supporting sustainability, resilience, ecosystem services, biodiversity, and local to global interconnections of ecosystems. Emerging from the new knowledge about how ecosystems function and the application of the systems ecology approach was the collaboration of scientists, managers, decision-makers, and stakeholders locally and globally. Today’s concepts of ecosystem management and related ideas, such as sustainable agriculture, ecosystem health and restoration, consequences of and adaptation to climate change, and many other important local to global challenges are a direct result of the SEP.
Fundamental knowledge about the processes that control the functioning of the biophysical workings of ecosystems has expanded exponentially since the late 1960s. Scientists, then, had only primitive knowledge about C, N, P, S, and H2O cycles; plant, animal, and soil microbial interactions and dynamics; and land, atmosphere, and water interactions. With the advent of systems ecology paradigm (SEP) and the explosion of technologies supporting field and laboratory research, scientists throughout the world were able to assemble the knowledge base known today as ecosystem science. This chapter describes, through the eyes of scientists associated with the Natural Resource Ecology Laboratory (NREL) at Colorado State University (CSU), the evolution of the SEP in discovering how biophysical systems at small scales (ecological sites, landscapes) function as systems. The NREL and CSU are epicenters of the development of ecosystem science. Later, that knowledge, including humans as components of ecosystems, has been applied to small regions, regions, and the globe. Many research results that have formed the foundation for ecosystem science and management of natural resources, terrestrial environments, and its waters are described in this chapter. Throughout are direct and implicit references to the vital collaborations with the global network of ecosystem scientists.
Systemic ventricular end-diastolic pressure is important in patients with single ventricle heart disease. Predictors of an elevated systemic ventricular end-diastolic pressure prior to bidirectional Glenn operation have been incompletely identified.
Methods:
All patients who underwent bidirectional Glenn operation operation at our centre between January 2007 and March 2017 were retrospectively identified and patient variables were extracted. For patients who had undergone Fontan operation at the time of this study, post-Fontan patient variables were also extracted.
Results:
One-hundred patients were included with a median age at pre-bidirectional Glenn operation catheterisation of 4.5 months. In total, 71 (71%) patients had a systemic right ventricle. At the pre-bidirectional Glenn operation catheterisation, the mean systemic ventricular end-diastolic pressure was higher amongst those with systemic right ventricle compared to left ventricle (9.1 mmHg ± 2.1 versus 7.7 ± 2.7 mmHg, p < 0.01). On univariate analysis, pre-bidirectional Glenn operation systemic ventricular end-diastolic pressure was positively associated with the presence of a systemic right ventricle (p < 0.01), history of recoarctation (p = 0.03), history of Norwood operation (p = 0.04), and ventricular systolic pressure (p < 0.01). On multivariate analysis, systemic ventricular end-diastolic pressure was positively associated with the presence of a systemic right ventricle (p < 0.01) and ventricular systolic pressure (p < 0.01). Amongst those who had undergone Fontan operation at the time of study (n = 49), those with a higher pre-bidirectional Glenn operation systemic ventricular end-diastolic pressure were more likely to have experienced death, transplantation, or listed for transplantation (p = 0.02) and more likely to have had heart failure symptoms (p = 0.04) at a mean time from Fontan of 5.2 years ± 1.3.
Conclusions:
In patients undergoing bidirectional Glenn operation operation, the volume-loaded, pre-bidirectional Glenn operation state may expose diastolic dysfunction that has prognostic value.
An increasing number of unexpectedly diverse benthic communities are being reported from microbially precipitated carbonate facies in shallow-marine platform settings after the end-Permian mass extinction. Ostracoda, which was one of the most diverse and abundant metazoan groups during this interval, recorded its greatest diversity and abundance associated with these facies. Previous studies, however, focused mainly on taxonomic diversity and, therefore, left room for discussion of paleoecological significance. Here, we apply a morphometric method (semilandmarks) to investigate morphological variance through time to better understand the ecological consequences of the end-Permian mass extinction and to examine the hypothesis that microbial mats played a key role in ostracod survival. Our results show that taxonomic diversity and morphological disparity were decoupled during the end-Permian extinction and that morphological disparity declined rapidly at the onset of the end-Permian extinction, even though the high diversity of ostracods initially survived in some places. The decoupled changes in taxonomic diversity and morphological disparity suggest that the latter is a more robust proxy for understanding the ecological impact of the extinction event, and the low morphological disparity of ostracod faunas is a consequence of sustained environmental stress or a delayed post-Permian radiation. Furthermore, the similar morphological disparity of ostracods between microbialite and non-microbialite facies indicates that microbial mats most likely represent a taphonomic window rather than a biological refuge during the end-Permian extinction interval.
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.
Hyperprolific sows rear more piglets than they have teats, and to accommodate this, milk replacers are often offered as a supplement. Milk replacers are based on bovine milk, yet components of vegetable origin are often added. This may reduce growth, but could also accelerate maturational changes. Therefore, we investigated the effect of feeding piglets a milk replacer with gradually increasing levels of wheat flour on growth, gut enzyme activity and immune function compared with a diet based entirely on bovine milk. The hypothesis tested was that adding a starch component (wheat flour) induces maturation of the mucosa as measured by higher digestive activity and improved integrity and immunity of the small intestines (SI). To test this hypothesis, piglets were removed from the sow at day 3 and fed either a pure milk replacer diet (MILK) or from day 11 a milk replacer diet with increasing levels of wheat (WHEAT). The WHEAT piglets had an increased enzyme activity of maltase and sucrase in the proximal part of the SI compared with the MILK group. There were no differences in gut morphology, histopathology and gene expression between the groups. In conclusion, the pigs given a milk replacer with added wheat displayed immunological and gut mucosal enzyme maturational changes, indicatory of adaptation towards a vegetable-based diet. This was not associated with any clinical complications, and future studies are needed to show whether this could improve responses in the subsequent weaning process.
Over the last two decades, heart centres have developed strategies to meet the neurodevelopmental needs of children with congenital heart disease. Since the publication of guidelines in 2012, cardiac neurodevelopmental follow-up programmes have become more widespread. Local neurodevelopmental programmes, however, have been developed independently in widely varying environments. We sought to characterise variation in structure and personnel in cardiac neurodevelopmental programmes. A 31-item survey was sent to all member institutions of the Cardiac Neurodevelopmental Outcome Collaborative. Multidisciplinary teams at each centre completed the survey. Responses were compiled in a descriptive fashion. Of the 29 invited centres, 23 responded to the survey (79%). Centres reported more anticipated neurodevelopment visits between birth and 5 years of age (median 5, range 2–8) than 5–18 years (median 2, range 0–10) with 53% of centres lacking any standard for routine neurodevelopment evaluations after 5 years of age. Estimated annual neurodevelopment clinic volume ranged from 85 to 428 visits with a median of 16% of visits involving children >5 years of age. Among responding centres, the Bayley Scales of Infant and Toddler Development and Wechsler Preschool and Primary Scale of Intelligence were the most routinely used tests. Neonatal clinical assessment was more common (64%) than routine neonatal brain imaging (23%) during hospitalisation. In response to clinical need and published guidelines, centres have established formal cardiac neurodevelopment follow-up programmes. Centres vary considerably in their approaches to routine screening and objective testing, with many centres currently focussing their resources on evaluating younger patients.
SHEA endorses adhering to the recommendations by the CDC and ACIP for immunizations of all children and adults. All persons providing clinical care should be familiar with these recommendations and should routinely assess immunization compliance of their patients and strongly recommend all routine immunizations to patients. All healthcare personnel (HCP) should be immunized against vaccine-preventable diseases as recommended by the CDC/ACIP (unless immunity is demonstrated by another recommended method). SHEA endorses the policy that immunization should be a condition of employment or functioning (students, contract workers, volunteers, etc) at a healthcare facility. Only recognized medical contraindications should be accepted for not receiving recommended immunizations.
Antarctica's ice shelves modulate the grounded ice flow, and weakening of ice shelves due to climate forcing will decrease their ‘buttressing’ effect, causing a response in the grounded ice. While the processes governing ice-shelf weakening are complex, uncertainties in the response of the grounded ice sheet are also difficult to assess. The Antarctic BUttressing Model Intercomparison Project (ABUMIP) compares ice-sheet model responses to decrease in buttressing by investigating the ‘end-member’ scenario of total and sustained loss of ice shelves. Although unrealistic, this scenario enables gauging the sensitivity of an ensemble of 15 ice-sheet models to a total loss of buttressing, hence exhibiting the full potential of marine ice-sheet instability. All models predict that this scenario leads to multi-metre (1–12 m) sea-level rise over 500 years from present day. West Antarctic ice sheet collapse alone leads to a 1.91–5.08 m sea-level rise due to the marine ice-sheet instability. Mass loss rates are a strong function of the sliding/friction law, with plastic laws cause a further destabilization of the Aurora and Wilkes Subglacial Basins, East Antarctica. Improvements to marine ice-sheet models have greatly reduced variability between modelled ice-sheet responses to extreme ice-shelf loss, e.g. compared to the SeaRISE assessments.
Reward Deficiency Syndrome (RDS) is an umbrella term for all drug and nondrug addictive behaviors, due to a dopamine deficiency, “hypodopaminergia.” There is an opioid-overdose epidemic in the USA, which may result in or worsen RDS. A paradigm shift is needed to combat a system that is not working. This shift involves the recognition of dopamine homeostasis as the ultimate treatment of RDS via precision, genetically guided KB220 variants, called Precision Behavioral Management (PBM). Recognition of RDS as an endophenotype and an umbrella term in the future DSM 6, following the Research Domain Criteria (RDoC), would assist in shifting this paradigm.
Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
Crocodilians are distributed widely through the tropics and subtropics, and several species pose a substantial threat to human life. This has important implications for human safety and crocodilian conservation. Understanding the drivers of crocodilian attacks on people could help minimize future attacks and inform conflict management. Crocodilian attacks follow a seasonal pattern in many regions, but there has been limited analysis of the relationship between attack occurrence and fine-scale contemporaneous environmental conditions. We use methods from environmental niche modelling to explore the relationships between attacks on people and abiotic predictors at a daily temporal resolution for the Nile crocodile Crocodylus niloticus in South Africa and Eswatini (formerly Swaziland), and the American alligator Alligator mississippiensis in Florida, USA. Our results indicate that ambient daily temperature is the most important abiotic temporal predictor of attack occurrence for both species, with attack likelihood increasing markedly when mean daily temperatures exceed 18 °C and peaking at 28 °C. It is likely that this relationship is explained partially by human propensity to spend time in and around water in warmer weather but also by the effect of temperature on crocodilian hunting behaviour and physiology, especially the ability to digest food. We discuss the potential of our findings to contribute to the management of crocodilians, with benefits for both human safety and conservation, and the application of environmental niche modelling for understanding human–wildlife conflicts involving both ectotherms and endotherms.
We present a calibration component for the Murchison Widefield Array All-Sky Virtual Observatory (MWA ASVO) utilising a newly developed PostgreSQL database of calibration solutions. Since its inauguration in 2013, the MWA has recorded over 34 petabytes of data archived at the Pawsey Supercomputing Centre. According to the MWA Data Access policy, data become publicly available 18 months after collection. Therefore, most of the archival data are now available to the public. Access to public data was provided in 2017 via the MWA ASVO interface, which allowed researchers worldwide to download MWA uncalibrated data in standard radio astronomy data formats (CASA measurement sets or UV FITS files). The addition of the MWA ASVO calibration feature opens a new, powerful avenue for researchers without a detailed knowledge of the MWA telescope and data processing to download calibrated visibility data and create images using standard radio astronomy software packages. In order to populate the database with calibration solutions from the last 6 yr we developed fully automated pipelines. A near-real-time pipeline has been used to process new calibration observations as soon as they are collected and upload calibration solutions to the database, which enables monitoring of the interferometric performance of the telescope. Based on this database, we present an analysis of the stability of the MWA calibration solutions over long time intervals.
OBJECTIVES/GOALS: Early age at menopause has been linked to increased risk of cardiovascular disease; however, there is limited evidence for a relationship between early menopause and heart failure (HF). We examined whether early menopause is associated with incident HF among women in the southeastern United States. METHODS/STUDY POPULATION: The Southern Community Cohort Study enrolled ~86,000 low-income black and white adults from 2002 to 2009. Participants for this analysis were 11,948 women who were postmenopausal at enrollment, had no history of HF, and were on Medicaid or Medicare. HF events were ascertained using ICD-9 codes 428.x via linkage of the cohort with CMS Research Identifiable Files through December 31, 2010. Early menopause was defined as self-reported age at menopause less than 45 years. Hazard ratios (HRs) and 95% confidence intervals (CIs) were computed from multivariable Cox regression models, overall and by race, adjusting for demographic, lifestyle, and reproductive factors, including reason for menopause. RESULTS/ANTICIPATED RESULTS: At baseline, mean age was 58±9 years, and 65% of participants were black. Among women with early menopause, 76% (n = 4,836) had menopause due to hysterectomy or oophorectomy. In women with later menopause, 74% (n = 4,102) reported natural menopause. During a median follow-up of 5.0 years (range 3.1-6.7), 2,157 incident HF events occurred. Compared with women with later onset of menopause, those with early menopause had increased HF risk (HR: 1.27, 95% CI: 1.10–1.47). Risk of HF associated with early menopause was similar in white and black women (p-value for interaction: 0.13). DISCUSSION/SIGNIFICANCE OF IMPACT: In this largely low-income population, early menopause was associated with an increased risk of developing HF. Women with early menopause represent a potential target population for future interventions to decrease risk of HF and cardiovascular risk factors.
Emergency Medical Services (EMS) systems have developed protocols for prehospital activation of the cardiac catheterization laboratory for patients with suspected ST-elevation myocardial infarction (STEMI) to decrease first-medical-contact-to-balloon time (FMC2B). The rate of “false positive” prehospital activations is high. In order to decrease this rate and expedite care for patients with true STEMI, the American Heart Association (AHA; Dallas, Texas USA) developed the Mission Lifeline PreAct STEMI algorithm, which was implemented in Los Angeles County (LAC; California USA) in 2015. The hypothesis of this study was that implementation of the PreAct algorithm would increase the positive predictive value (PPV) of prehospital activation.
Methods:
This is an observational pre-/post-study of the effect of the implementation of the PreAct algorithm for patients with suspected STEMI transported to one of five STEMI Receiving Centers (SRCs) within the LAC Regional System. The primary outcome was the PPV of cardiac catheterization laboratory activation for percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The secondary outcome was FMC2B.
Results:
A total of 1,877 patients were analyzed for the primary outcome in the pre-intervention period and 405 patients in the post-intervention period. There was an overall decrease in cardiac catheterization laboratory activations, from 67% in the pre-intervention period to 49% in the post-intervention period (95% CI for the difference, -14% to -22%). The overall rate of cardiac catheterization declined in post-intervention period as compared the pre-intervention period, from 34% to 30% (95% CI, for the difference -7.6% to 0.4%), but actually increased for subjects who had activation (48% versus 58%; 95% CI, 4.6%-15.0%). Implementation of the PreAct algorithm was associated with an increase in the PPV of activation for PCI or CABG from 37.9% to 48.6%. The overall odds ratio (OR) associated with the intervention was 1.4 (95% CI, 1.1-1.8). The effect of the intervention was to decrease variability between medical centers. There was no associated change in average FMC2B.
Conclusions:
The implementation of the PreAct algorithm in the LAC EMS system was associated with an overall increase in the PPV of cardiac catheterization laboratory activation.
The climate crisis requires nations to achieve human well-being with low national levels of carbon emissions. Countries vary from one another dramatically in how effectively they convert resources into well-being, and some nations with low levels of emissions have relatively high objective and subjective well-being. We identify urgent research and policy agendas for four groups of countries with either low or high emissions and well-being indicators. Least studied are those with low well-being and high emissions. Understanding social and political barriers to switching from high-carbon to lower-carbon modes of production and consumption, and ways to overcome them, will be fundamental.
Precise radiocarbon (14C) dating of sedimentary sequences is important for developing robust chronologies of environmental change, but sampling of suitable components can be challenging in highly dynamic landscapes. Here we investigate radiocarbon determinations of different peat size fractions from six peat sites, representing a range of geomorphological contexts on the South Atlantic subantarctic islands of the Falklands and South Georgia. To investigate the most suitable fraction for dating, 112 measurements were obtained from three components within selected horizons: a fine fraction <0.2 mm, a coarse fraction >0.2 mm, and bulk material. We find site selection is critical, with locations surrounded by high-ground and/or relatively slowly accumulating sites more susceptible to the translocation of older carbon. Importantly, in locations with reduced potential for redeposition of material, our results show that there is no significant or systematic difference between ages derived from bulk material, fine or coarse (plant macrofossil) material, providing confidence in the resulting age model. Crucially, in areas comprising complex terrain with extreme relief, we recommend dating macrofossils or bulk carbon rather than a fine fraction, or employing comprehensive dating of multiple sedimentary fractions to determine the most reliable fraction(s) for developing a robust chronological framework.
OBJECTIVES/SPECIFIC AIMS: The Life’s Simple 7 (LS7) metric was created by the American Heart Association with the goal of educating the public on seven modifiable factors that contribute to heart health. While it is well documented that these ideal health behaviors lower risk of cardiovascular disease (CVD) in the general population, the association between the LS7 ideal health metrics and end stage renal disease (ESRD) risk has not been examined in a lower socioeconomic population at high risk for both ESRD and CVD. Our objective is to examine the association between the LS7 score and incident ESRD in a cohort of white and black men and women in the southeastern US, where rates of CVD and ESRD are high. METHODS/STUDY POPULATION: The Southern Community Cohort Study recruited ~86,000 low-income blacks and whites in the southeastern US (2002-2009). Utilizing a nested case-control design, our analysis included 1628 incident cases of ESRD identified via linkage of the cohort with the United States Renal Data System (USRDS) from January 1, 2002 to March 31, 2015. Controls (n = 4884) were individually matched 3:1 with ESRD cases based on age, sex, and race. Demographic, medical, and lifestyle information were obtained via baseline questionnaire. The AHA definitions for ideal health were used for non-smoking (never or quit >12 months), body mass index (BMI<25kg/m2) and physical activity (>75 min/week of vigorous physical activity or >150min/week of moderate/vigorous activity). Modified definitions were used for consuming a healthy diet [Healthy Eating Index (HEI10) score>70] and for blood pressure, fasting plasma glucose, and total cholesterol, based on self-reported no history of diagnosis of hypertension, diabetes, and hypercholesterolemia, respectively. The number of ideal health parameters were summed to generate the LS7 score, which ranged from 0-7 with higher scores indicating more ideal health. Adjusted odds ratios (95% confidence intervals) for incident ESRD associated with LS7 score were calculated using conditional logistic regression models, adjusting for income and education. The SCCS ESRD case-cohort dataset will be available by TS 2019 and analyses will be completed to adjust for baseline estimated glomerular filtration rate (eGFR) as a marker of kidney function and to examine whether eGFR modifies the relationship between LS7 and incident ESRD. RESULTS/ANTICIPATED RESULTS: At baseline, mean age was 54 years, 55% (3600) of participants were women, and 87% (5656) were black. A total of 58% (943) of ESRD cases were non-smokers compared to 54% (2633) of controls. ESRD cases had higher prevalence of BMI>25 kg/m2 (81% vs. 74%), hypertension (84% vs. 59%), hypercholesterolemia (48% vs. 34%), and diabetes (66% vs. 22%) compared to controls. A total of 18% (839) of controls and 12% (194) of ESRD cases met ideal exercise recommendations, and 20% of either cases (302) or controls (916) had a HEI10 score above 70. The median LS7 score for controls and ESRD cases was 3 and 2, respectively, and 17% (983) of participants had a low score (0-1) while 2% (105) met 6 or 7 ideal health metrics. Higher LS7 score was associated with lower odds of ESRD (P-trend<0.001). Participants with LS7 score >3 (above median) had 75% reduced odds of ESRD (OR 0.25; 95% CI 0.22, 0.29) compared to those with a score of 2 or less. DISCUSSION/SIGNIFICANCE OF IMPACT: In the SCCS population, the presence of any 3 or more ideal health behaviors is associated with reduced odds of developing ESRD. The components of the LS7 represent important modifiable risk factors that may be targets for future interventions driven by the patient. The attributable risk due to each factor is needed to dissect which ideal behaviors are the most beneficial.
The euarthropod Luohuilinella deletres sp. nov. is described from rare material from the Chengjiang biota, Cambrian Series 2, Stage 3, of Yunnan Province, China. Phylogenetic analysis recovers a xandarellid affinity for L. deletres, representing only the fifth described species of this clade. L. deletres possesses a head shield that is about one-fifth of the total body length and a trunk with 30 tergites, the reduced anterior-most tergite and terminal three tergites lacking pleural elongations. Anteriorly situated notches in the head shield are associated with stalked eyes, in contrast to the more posterior, enclosed eye slits present in Xandarella. Posterior to the antennae there are at least 11 pairs of biramous appendages preserved, including three pairs in the head. The morphology of the midline gut of L. deletres, in which lateral, unbranched diverticula are wider towards the front of the body, is a characteristic also found in various trilobites. The dorsoventrally flattened exoskeleton suggests a benthic or nektobenthic mode of life for L. deletres, as for other trilobitomorphs, and it likely used its well-developed anteriorly positioned eyes for searching out food, either to scavenge or to find prey.