Drivers of nitrogen transfer in stream food webs across continents.

Studies of trophic-level material and energy transfers are central to ecology. The use of isotopic tracers has now made it possible to measure trophic transfer efficiencies of important nutrients and to better understand how these materials move through food webs. We analyzed data from thirteen 15 N-ammonium tracer addition experiments to quantify N transfer from basal resources to animals in headwater streams with varying physical, chemical, and biological features. N transfer efficiencies from primary uptake compartments (PUCs; heterotrophic microorganisms and primary producers) to primary consumers was lower (mean 11.5%, range <1% to 43%) than N transfer efficiencies from primary consumers to predators (mean 80%, range 5% to >100%). Total N transferred (as a rate) was greater in streams with open compared to closed canopies and overall N transfer efficiency generally followed a similar pattern, although was not statistically significant. We used principal component analysis to condense a suite of site characteristics into two environmental components. Total N uptake rates among trophic levels were best predicted by the component that was correlated with latitude, DIN:SRP, GPP:ER, and percent canopy cover. N transfer efficiency did not respond consistently to environmental variables. Our results suggest that canopy cover influences N movement through stream food webs because light availability and primary production facilitate N transfer to higher trophic levels.

Non-eligibility for reperfusion therapy in patients presenting with ST-segment elevation myocardial infarction: Contemporary insights from the National Cardiovascular Data Registry (NCDR).

BACKGROUND: Reperfusion therapy is lifesaving in patients presenting with ST-segment elevation myocardial infarction (STEMI). Contemporary data describing the characteristics and outcomes of patients presenting with STEMI not receiving reperfusion therapy are lacking. METHODS: Using the ACTION Registry-GWTG database, we examined 219,726 STEMI patients (January 2007-December 2013) at 721 percutaneous coronary intervention (PCI)-capable hospitals in United States. Clinical characteristics and in-hospital outcomes were stratified by those who underwent reperfusion (n = 188,200; 86%), those who did not undergo reperfusion with a reason for ineligibility (n = 27,179; 12%), and those without reperfusion but had no reason for ineligibility (n = 4,347; 2%). RESULTS: Compared with STEMI patients receiving reperfusion therapy, the nonreperfusion groups were older, were more often female, and had higher rates of hypertension, diabetes, prior myocardial infarction, prior stroke, atrial fibrillation, and left bundle-branch block and heart failure on presentation. The major reason for reperfusion noneligibility was coronary anatomy not suitable for PCI (33%). Presence of 3-vessel coronary disease was more common in the nonreperfusion groups (with or without a documented reason) compared with reperfusion group (38% and 36% vs 26%, P < .001, respectively). In-hospital mortality was higher in patients not receiving reperfusion therapy with or without a documented reason compared with the reperfusion group (adjusted odds ratio [95% CI] 1.88 [1.78-1.99] and 1.37 [1.21-1.57], respectively). CONCLUSION: Most patients with STEMI not receiving reperfusion therapy had a documented reason. Coronary anatomy not suitable for PCI was the major contributor to ineligibility. In-hospital mortality was higher in patients not receiving reperfusion therapy.

Testing the generality of above-ground biomass allometry across plant functional types at the continent scale.

Accurate ground-based estimation of the carbon stored in terrestrial ecosystems is critical to quantifying the global carbon budget. Allometric models provide cost-effective methods for biomass prediction. But do such models vary with ecoregion or plant functional type? We compiled 15 054 measurements of individual tree or shrub biomass from across Australia to examine the generality of allometric models for above-ground biomass prediction. This provided a robust case study because Australia includes ecoregions ranging from arid shrublands to tropical rainforests, and has a rich history of biomass research, particularly in planted forests. Regardless of ecoregion, for five broad categories of plant functional type (shrubs; multistemmed trees; trees of the genus Eucalyptus and closely related genera; other trees of high wood density; and other trees of low wood density), relationships between biomass and stem diameter were generic. Simple power-law models explained 84-95% of the variation in biomass, with little improvement in model performance when other plant variables (height, bole wood density), or site characteristics (climate, age, management) were included. Predictions of stand-based biomass from allometric models of varying levels of generalization (species-specific, plant functional type) were validated using whole-plot harvest data from 17 contrasting stands (range: 9-356 Mg ha(-1) ). Losses in efficiency of prediction were <1% if generalized models were used in place of species-specific models. Furthermore, application of generalized multispecies models did not introduce significant bias in biomass prediction in 92% of the 53 species tested. Further, overall efficiency of stand-level biomass prediction was 99%, with a mean absolute prediction error of only 13%. Hence, for cost-effective prediction of biomass across a wide range of stands, we recommend use of generic allometric models based on plant functional types. Development of new species-specific models is only warranted when gains in accuracy of stand-based predictions are relatively high (e.g. high-value monocultures).

Comparative validity of the Adult Attachment Interview and the Adult Attachment Projective.

The Adult Attachment Interview (AAI) and the Adult Attachment Projective (AAP) purport to measure the same attachment classifications. The aims of this study were to determine the concurrent validity of the AAI and AAP, and to compare their ability to predict indicators of risk associated with socioeconomic status (SES), depression, and 5-HTTLPR genotype. Results indicated no agreement between AAI and AAP attachment classifications in a sample of late adolescents. As predicted, individuals classified as "unresolved" with regard to loss or trauma were significantly more likely to be of lower SES, have higher levels of depression, and have the 5-HTTLPR "ss" genotype than individuals with secure, preoccupied, or dismissing attachments. These associations, however, were only significant when attachment was classified with the AAI. Results suggest that the AAI and AAP measure different facets of attachment as a result of their unique methodologies and coding criteria. Further research is needed to support their comparability before investigators can assume that the AAP is a valid substitute for the AAI.

Rare case of intrahepatic splenosis masquerading as malignancy.

A 54-year-old man presented with abdominal pain and a history of post-traumatic splenectomy 33 years prior, imaging revealed an incidental hepatic mass.

Corrigendum: Potential genetic overlap between insomnia and sleep symptoms in major depressive disorder: A polygenic risk score analysis.

[This corrects the article DOI: 10.3389/fpsyt.2021.734077.].

Potential Genetic Overlap Between Insomnia and Sleep Symptoms in Major Depressive Disorder: A Polygenic Risk Score Analysis.

Background: The prevalence of insomnia and hypersomnia in depressed individuals is substantially higher than that found in the general population. Unfortunately, these concurrent sleep problems can have profound effects on the disease course. Although the full biology of sleep remains to be elucidated, a recent genome-wide association (GWAS) of insomnia, and other sleep traits in over 1 million individuals was recently published and provides many promising hits for genetics of insomnia in a population-based sample. Methods: Using data from the largest available GWAS of insomnia and other sleep traits, we sought to test if sleep variable PRS scores derived from population-based studies predicted sleep variables in samples of depressed cases [Psychiatric Genomics Consortium - Major Depressive Disorder subjects (PGC MDD)]. A leave-one-out analysis was performed to determine the effects that each individual study had on our results. Results: The only significant finding was for insomnia, where p-value threshold, p = 0.05 was associated with insomnia in our PGC MDD sample (R 2 = 1.75-3, p = 0.006). Conclusion: Our results reveal that <1% of variance is explained by the variants that cover the two significant p-value thresholds, which is in line with the fact that depression and insomnia are both polygenic disorders. To the best of our knowledge, this is the first study to investigate genetic overlap between the general population and a depression sample for insomnia, which has important treatment implications, such as leading to novel drug targets in future research efforts.

Epigenetic marks as the link between environment and development: examination of the associations between attachment, socioeconomic status, and methylation of the SLC6A4 gene.

BACKGROUND: Epigenetic processes act as a link between environment and individual development. This pilot study examined the association between socioeconomic status (SES), attachment, and methylation of the promoter region of the serotonin transporter gene (SLC6A4). METHODS: Attachment classification and SLC6A4 methylation was determined in 100 late adolescents. We hypothesized that (1) SES would interact with methylation to predict higher unresolved loss (UL) or trauma scores on the Adult Attachment Interview; (2) across SES, participants with unresolved attachment would have lower levels of methylation than organized or secure participants; and (3) within the unresolved classification, SES would predict methylation. RESULTS: Results showed that lower methylation and low-SES were associated with higher UL, and higher methylation and low-SES were associated with higher unresolved trauma. Across SES, unresolved participants had lower levels of methylation than organized participants. Within the unresolved category, low-SES unresolved participants had higher levels of methylation than mid/upper-SES participants. SES was unrelated to methylation within the secure and organized categories. CONCLUSIONS: These results suggest that the quality of attachment relationships may impact epigenetic processes.

The needs of patients dying of chronic obstructive pulmonary disease in the community.

BACKGROUND: Ninety percent of the last year of life of a terminally ill patient is spent at home, but possible drawbacks to domicillary terminal care have been suggested. Most previous studies have taken place in secondary care settings, and have often obtained relatives' views of patients' needs rather than those of the patient. OBJECTIVES: Our aim was to determine the needs of patients dying in primary care from chronic obstructive pulmonary disease (COPD). METHODS: Semi-structured interviews were undertaken with 16 patients who were having maximal therapy for COPD, who were thought likely to die in the year following the commencement of the study. RESULTS: Five themes were identified. (i) Patients' information needs and the future course of their illnesses. Information needs were often variable and patients were sometimes unwilling to contemplate the future. (ii) The impact of symptoms on patients' lives. Dyspnoea was a particular problem. (iii) Attitudes towards and opinions on smoking, which many acknowledged as being causal. (iv) Attitudes to help received. Many patients relied on their family; most patients felt their doctors were helpful although some expressed reservations. (v) Patients' expressed needs. These usually focused on mobility, and many patients would not express needs even when prompted. CONCLUSION: Poor symptom control remains an important cause of distress. The low number of expressed needs may reflect patients' unwillingness to appear ungrateful, but the variability of information needs emphasizes the importance of an individual approach to patients with an apparently homogenous disease