Soil carbon (C) is a critical component of Earth system models (ESMs), and its diverse representations are a major source of the large spread across models in the terrestrial C sink from the third to ...fifth assessment reports of the Intergovernmental Panel on Climate Change (IPCC). Improving soil C projections is of a high priority for Earth system modeling in the future IPCC and other assessments. To achieve this goal, we suggest that (1) model structures should reflect real‐world processes, (2) parameters should be calibrated to match model outputs with observations, and (3) external forcing variables should accurately prescribe the environmental conditions that soils experience. First, most soil C cycle models simulate C input from litter production and C release through decomposition. The latter process has traditionally been represented by first‐order decay functions, regulated primarily by temperature, moisture, litter quality, and soil texture. While this formulation well captures macroscopic soil organic C (SOC) dynamics, better understanding is needed of their underlying mechanisms as related to microbial processes, depth‐dependent environmental controls, and other processes that strongly affect soil C dynamics. Second, incomplete use of observations in model parameterization is a major cause of bias in soil C projections from ESMs. Optimal parameter calibration with both pool‐ and flux‐based data sets through data assimilation is among the highest priorities for near‐term research to reduce biases among ESMs. Third, external variables are represented inconsistently among ESMs, leading to differences in modeled soil C dynamics. We recommend the implementation of traceability analyses to identify how external variables and model parameterizations influence SOC dynamics in different ESMs. Overall, projections of the terrestrial C sink can be substantially improved when reliable data sets are available to select the most representative model structure, constrain parameters, and prescribe forcing fields.
Key Points
First‐order decay functions capture macroscopic SOC dynamics, but their underpinnings need more study
Optimal parameter calibration through data assimilation is a high priority to reduce model biases
Traceability analyses are needed to understand the consequences of variation in driving variables
There is little information on the clinical presentation, functional impact, and psychiatric characteristics of misophonia in youth, an increasingly recognized syndrome characterized by high ...emotional reactivity to certain sounds and associated visual stimuli.
One-hundred-two youth (8–17 years-old) with misophonia and their parents were recruited and compared with 94 youth with anxiety disorders. Participants completed validated assessments of misophonia severity, quality of life, as well as psychiatric symptoms and diagnoses.
The most common misophonia triggers included eating (96 %), breathing (84 %), throat sounds (66 %), and tapping (54 %). Annoyance/irritation, verbal aggression, avoidance behavior, and family impact were nearly universal. Misophonia severity was associated with internalizing symptoms, child-reported externalizing behaviors, and poorer quality of life. High rates of comorbidity with internalizing and neurodevelopmental disorders were found. Quality of life and externalizing behaviors were not significantly different between misophonia and anxiety samples; internalizing symptoms and autism characteristics were significantly higher among youth with anxiety disorders.
This self-selected sample was characterized by limited multicultural diversity.
This study presents misophonia as a highly impairing psychiatric syndrome. Future interdisciplinary work should clarify the mechanisms of misophonia, establish evidence-based treatments, and extend these findings to randomly sampled and more culturally diverse populations.
•Misophonia was associated with substantial functional impairment in this sample•Anger/irritation, avoidance behavior, and impact to family life were nearly universal•Anxiety disorders were common (45%) as were current or past depressive disorders (46%)•Other common comorbidities were attention-deficit/hyperactivity disorder (21%) and tic disorders (13%)•Youth with misophonia had elevated internalizing symptoms and autism features (though less than youth with anxiety)
In a population-based study, emphysema was quantified by computed tomography, pulmonary function was assessed by spirometry, and cardiac volumes and function were measured by magnetic resonance ...imaging. Both percent emphysema and the severity of airflow obstruction were linearly related to reductions in left ventricular end-diastolic volume, stroke volume, and cardiac output. These effects were more pronounced among smokers.
In a population-based study, emphysema and the severity of airflow obstruction were linearly related to reductions in left ventricular end-diastolic volume, stroke volume, and cardiac output.
Chronic obstructive pulmonary disease (COPD), defined as airflow obstruction that is not fully reversible,
1
is currently the fourth leading cause of death in the United States.
2
COPD overlaps partially with emphysema, which is characterized by the destruction of alveolar walls and the permanent enlargement of air spaces distal to the terminal bronchioles.
1
,
3
Cor pulmonale, which can occur in very severe COPD, is characterized by elevated pulmonary vascular resistance and right heart failure, with associated reductions in left ventricular filling, left ventricular stroke volume, and cardiac output, although left ventricular ejection fraction is generally preserved.
4
–
7
This disorder may occur . . .
We present high time resolution airborne ethane (C2H6) and methane (CH4) measurements made in March and October 2013 as part of the Barnett Coordinated Campaign over the Barnett Shale formation in ...Texas. Ethane fluxes are quantified using a downwind flight strategy, a first demonstration of this approach for C2H6. Additionally, ethane-to-methane emissions ratios (C2H6:CH4) of point sources were observationally determined from simultaneous airborne C2H6 and CH4 measurements during a survey flight over the source region. Distinct C2H6:CH4 × 100% molar ratios of 0.0%, 1.8%, and 9.6%, indicative of microbial, low-C2H6 fossil, and high-C2H6 fossil sources, respectively, emerged in observations over the emissions source region of the Barnett Shale. Ethane-to-methane correlations were used in conjunction with C2H6 and CH4 fluxes to quantify the fraction of CH4 emissions derived from fossil and microbial sources. On the basis of two analyses, we find 71–85% of the observed methane emissions quantified in the Barnett Shale are derived from fossil sources. The average ethane flux observed from the studied region of the Barnett Shale was 6.6 ± 0.2 × 103 kg hr–1 and consistent across six days in spring and fall of 2013.
Pythium brassicum P1 Stanghellini, Mohammadi, Förster, and Adaskaveg is an oomycete root pathogen that has recently been characterized. It only attacks plant species belonging to Brassicaceae family, ...causing root necrosis, stunting, and yield loss. Since P. brassicum P1 is limited in its host range, this prompted us to sequence its whole genome and compare it to those of broad host range Pythium spp. such as P. aphanidermatum and P. ultimum var. ultimum. A genomic DNA library was constructed with a total of 374 million reads. The sequencing data were assembled using SOAPdenovo2, yielding a total genome size of 50.3 Mb contained in 5434 scaffolds, N50 of 30.2 Kb, 61.2% G+C content, and 13,232 putative protein-coding genes. Pythium brassicum P1 had 175 species-specific gene families, which is slightly below the normal average. Like P. ultimum, P. brassicum P1 genome did not encode any classical RxLR effectors or cutinases, suggesting a significant difference in virulence mechanisms compared to other oomycetes. Pythium brassicum P1 had a much smaller proportions of the YxSL sequence motif in both secreted and non-secreted proteins, relative to other Pythium species. Similarly, P. brassicum P1 had the fewest Crinkler (CRN) effectors of all the Pythium species. There were 633 proteins predicted to be secreted in the P. brassicum P1 genome, which is, again, slightly below average among Pythium genomes. Pythium brassicum P1 had only one cadherin gene with calcium ion-binding LDRE and DxND motifs, compared to Pythium ultimum having four copies. Pythium brassicum P1 had a reduced number of proteins falling under carbohydrate binding module and hydrolytic enzymes. Pythium brassicum P1 had a reduced complement of cellulase and pectinase genes in contrast to P. ultimum and was deficient in xylan degrading enzymes. The contraction in ABC transporter families in P. brassicum P1 is suggested to be the result of a lack of diversity in nutrient uptake and therefore host range.
Flaring is widely used by the fossil fuel industry to dispose of natural gas. Industry and governments generally assume that flares remain lit and destroy methane, the predominant component of ...natural gas, with 98% efficiency. Neither assumption, however, is based on real-world observations. We calculate flare efficiency using airborne sampling across three basins responsible for >80% of US flaring and combine these observations with unlit flare prevalence surveys. We find that both unlit flares and inefficient combustion contribute comparably to ineffective methane destruction, with flares effectively destroying only 91.1% (90.2, 91.8; 95% confidence interval) of methane. This represents a fivefold increase in methane emissions above present assumptions and constitutes 4 to 10% of total US oil and gas methane emissions, highlighting a previously underappreciated methane source and mitigation opportunity.
Fueling global warming
Flaring, the process of burning natural gas escaping from oil and gas wells, is primarily intended to combust the powerful greenhouse gas methane to minimize its emission. But is flaring as effective as is claimed? Plant
et al
. used airborne sampling to measure flare efficiency in three major gas production regions in the United States and found that methane emissions are five times higher than currently thought (see the Perspective by Duren and Gordon). Therefore, flaring is often not as efficient as presumed—or methane plumes simply are not combusted at all. —HJS
Natural gas flaring destroys much less methane than thought.
Abstract
A near-complete diploid nuclear genome and accompanying circular mitochondrial and chloroplast genomes have been assembled from the elite commercial diatom species
Nitzschia inconspicua
. ...The 50 Mbp haploid size of the nuclear genome is nearly double that of model diatom
Phaeodactylum tricornutum
, but 30% smaller than closer relative
Fragilariopsis cylindrus
. Diploid assembly, which was facilitated by low levels of allelic heterozygosity (2.7%), included 14 candidate chromosome pairs composed of long, syntenic contigs, covering 93% of the total assembly. Telomeric ends were capped with an unusual 12-mer, G-rich, degenerate repeat sequence. Predicted proteins were highly enriched in strain-specific marker domains associated with cell-surface adhesion, biofilm formation, and raphe system gliding motility. Expanded species-specific families of carbonic anhydrases suggest potential enhancement of carbon concentration efficiency, and duplicated glycolysis and fatty acid synthesis pathways across cytosolic and organellar compartments may enhance peak metabolic output, contributing to competitive success over other organisms in mixed cultures. The
N. inconspicua
genome delivers a robust new reference for future functional and transcriptomic studies to illuminate the physiology of benthic pennate diatoms and harness their unique adaptations to support commercial algae biomass and bioproduct production.
Abstract Background Pulmonary emphysema is divided into 3 major subtypes at autopsy: centrilobular, paraseptal, and panlobular emphysema. These subtypes can be defined by visual assessment on ...computed tomography (CT); however, clinical characteristics of emphysema subtypes on CT are not well defined. We developed a reliable approach to visual assessment of emphysema subtypes on CT and examined if emphysema subtypes have distinct characteristics. Methods The Multi-Ethnic Study of Atherosclerosis COPD Study recruited smokers with chronic obstructive pulmonary disease (COPD) and controls ages 50-79 years with ≥10 pack-years. Participants underwent CT following a standardized protocol. Definitions of centrilobular, paraseptal, and panlobular emphysema were obtained by literature review. Six-minute walk distance and pulmonary function were performed following guidelines. Results Twenty-seven percent of 318 smokers had emphysema on CT. Interrater reliability of emphysema subtype was substantial (K: 0.70). Compared with participants without emphysema, individuals with centrilobular or panlobular emphysema had greater dyspnea, reduced walk distance, greater hyperinflation, and lower diffusing capacity. In contrast, individuals with paraseptal emphysema were similar to controls, except for male predominance. Centrilobular, but not panlobular or paraseptal, emphysema was associated with greater smoking history (+21 pack-years P <.001). Panlobular, but not other types of emphysema, was associated with reduced body mass index (−5 kg/m2 ; P = .01). Other than for dyspnea, these findings were independent of the forced expiratory volume in 1 second. Seventeen percent of smokers without COPD on spirometry had emphysema, which was independently associated with reduced walk distance. Conclusions Emphysema subtypes on CT are common in smokers with and without COPD. Centrilobular and panlobular emphysema, but not paraseptal emphysema, have considerable symptomatic and physiological consequences.
The goal of this randomized, blinded, crossover clinical trial was to determine whether Nuedexta (dextromethorphan and quinidine) enhanced speech, swallowing, and salivation in patients with ALS. ...Sixty patients with amyotrophic lateral sclerosis (ALS) received either Nuedexta or placebo for 28 to 30 days, followed by a 10 to 15-day washout period. Subsequently, patients were switched to the opposite treatment arm for the remaining days of the trial. The primary endpoint was a reduction in the self-report Center for Neurologic Study Bulbar Function Scale (CNS-BFS) score. The rater-administered ALS Functional Rating Scale Revised was the principal secondary endpoint. The CNS-BFS score improved with active treatment, decreasing from a mean of 59.3 in the placebo arm of the trial to 53.5 during the drug-treatment arm (
p
< 0.001). Each of the individual domains of bulbar function interrogated by the CNS-BFS responded to treatment with Nuedexta as follows: salivation: 15.8
versus
14.3 (
p
= 0.004); speech: 24.6
versus
22.2 (
p
= 0.003); swallowing: 18.9
versus
17.1 (
p
= 0.009). Similarly, the bulbar component of the ALS Functional Rating Scale Revised improved with active treatment (
p
= 0.003), although the drug did not affect the motor and respiratory components of this scale. This study is unique for several reasons. Firstly, it was driven by patient reports of improved speech and swallowing while taking Nuedexta for control of emotional lability. Secondly, the study was conducted over a short duration (70 days), and thirdly, a self-report scale was selected as the principle outcome measure. Considering the importance of bulbar functions, these results, if confirmed, point to an additional use of Nuedexta as an adjunct to the management of ALS.
•ICP-MS and automation have improved analytical reproducibility of TTE assays.•Repeat analysis is required by regulatory agency to rule out analytical outliers.•This study evaluated the utility of ...repeat analysis for copper, zinc, chromium, and cobalt in serum or plasma.•The likelihood of detecting analytical outliers by repeat analysis is very low.
Repeat testing is routinely required by regulatory bodies as a measure to rule out contamination in trace elements and heavy metal analysis, especially when the initial analysis result is outside the reference interval. However, its clinical utilities in detecting analytical measurement outliers have not been systematically evaluated in different clinical testing scenarios. In this study, we present an extensive evaluation of repeat testing and its comparison with the initial analysis in four serum and plasma trace element assays performed by inductively coupled plasma mass spectrometry. We demonstrate that the patient population distributions for these elements differ significantly from the reference interval established by healthy individuals. Accordingly, a significant proportion of the patient specimens would require repeat testing when using reference intervals as the threshold to perform repeat analysis. Crucially, comparison of the first analysis and repeat analysis reveals the limited utility of performing repeat measurements. The relative differences between the first and second measurements are consistent with the observed analytical imprecision of the assay and the likelihood of detecting actual analytical outliers is very low.
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