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Transferable and mechanistic understanding of cross-scale interactions is necessary to predict how coastal systems respond to global change. Cohesive datasets across geographically distributed sites can enable a mechanistic understanding of coastal ecosystem control points and examine how geographically transferable this knowledge is. To address the above research objectives, data were collected by the EXploration of Coastal Hydrobiogeochemistry Across a Network of Gradients and Experiments (EXCHANGE) Consortium– a regionally distributed network of researchers that collaborated on experimental design, methodology, collection, analysis, and publication. The EXCHANGE Consortium collected samples from 52 coastal terrestrial-aquatic interfaces (TAIs) during Fall of 2021. At each site, samples collected include soils from across a transverse elevation gradient (i.e., coastal upland forest, transitional forest, and wetland soils), surface waters, and nearshore sediments. The data described herein aims to characterize the baseline distribution and chemical forms of carbon, nutrients, iron redox and mineralogy across research sites in the Great Lakes and Mid-Atlantic regions (Chesapeake and Delaware Bays) of the continental USA. This first campaign measures surface water quality parameters (e.g., conductivity, pH, ORP, alkalinity, and total suspended solids); bulk geochemical parameters on water, soil, and sediment samples (e.g., carbon, nutrient, and ionic concentration and composition); physicochemical parameters of sediment and soil (soil pH, conductivity, bulk density, water retention); and the rate of O2 consumption in inundated sediment and soil samples. Future campaigns will focus on building off these baseline datasets to enable a mechanistic understanding of coastal ecosystem biogeochemical control points.

The fate of soil organic carbon (SOC) in boreal forests is dependent on the integrative ecosystem response to climate change. For example, boreal forest productivity is often nitrogen (N) limited, and climate warming can enhance N cycling and primary productivity. However, the net effect of this feedback on the SOC reservoir and its longevity with climate change remain unclear due to difficulty in detecting small differences between large and variable carbon (C) fluxes needed to determine net changes in soil reservoirs. The diagenetic state of SOC – resulting from the physicochemical and biological transformations that alter the original biomolecular composition of detrital inputs to soil over time – is useful for tracing the net response of SOC at the timescales relevant to climate change not usually discernible from fluxes and stocks alone. Here, we test two hypotheses using a mesic boreal forest climate transect: (1) the SOC diagenetic state is maintained across this climosequence, and (2) the maintenance of the SOC diagenetic state is a consequence of coupled soil C and N cycling, signifying the role of enhanced N cycling supporting SOC inputs that maintain SOC stocks within the warmer-climate forests. Shifts in nonvascular to vascular plant inputs with climate observed in these and other boreal forests highlighted the need to carefully separate biogeochemical indicators of SOC source from those signifying diagenetic alteration. We thus evaluated and applied lignin biomarkers to assess the diagenetic alteration of SOC in these boreal forest organic soils and directly compared the lignin diagenetic state with that of soil organic nitrogen (SON) assessed through amino acid composition. The lignin diagenetic state remained constant across the climate transect, indicating a balance between the input and removal of lignin in these mesic boreal forests. When combined with previous knowledge of these forest ecosystems, including the diagenetic state of SON and direct measures of C fluxes and stocks, the results indicate a coupled increase in C and N cycling with climate warming that supports forest productivity and maintains SOC stocks. This balance could markedly shift as other factors begin to limit forest productivity (e.g., trace nutrients, water) with further climate change or affect forest nutrient allocation (e.g., forest age or compositional change). Further application of the approach presented here could be used to detect the limits of this and other ecosystem–climate feedbacks, by providing a tractable and parameterizable index of the lignin state across large spatial scales, necessary for ecosystem-scale parameterizations.

Earth’s biogeochemical cycles are intimately tied to the biotic and abiotic processing of organic matter (OM). Spatial and temporal variation in OM chemistry is often studied using high resolution mass spectrometry (HRMS). An increasingly common approach is to use ecological metrics (e.g., within-sample diversity) to summarize high-dimensional HRMS data, notably Fourier transform ion cyclotron resonance MS (FTICR MS). However, problems arise when HRMS peak intensity data are used in a way that is analogous to abundances in ecological analyses (e.g., species abundance distributions). Using peak intensity data in this way requires the assumption that intensities act as direct proxies for concentrations, which is often invalid. Here we discuss theoretical expectations and provide empirical evidence why concentrations do not map to HRMS peak intensities. The theory and data show that comparisons of the same peak across samples (within-peak) may carry information regarding variation in relative concentration, but comparing different peaks (between-peak) within or between samples does not. We further developed a simulation model to study the quantitative implications of both within-peak and between-peak errors that decouple concentration from intensity. These implications are studied in terms of commonly used ecological metrics that quantify different aspects of diversity and functional trait values. We show that despite the poor linkages between concentration and intensity, the ecological metrics often perform well in terms of providing robust qualitative inferences and sometimes quantitatively-accurate estimates of diversity and trait values. We conclude with recommendations for using peak intensities in an informed and robust way for natural organic matter studies. A primary recommendation is the use and extension of the simulation model to provide objective, quantitative guidance on the degree to which conceptual and quantitative inferences can be made for a given analysis of a given dataset. Without objective guidance, researchers that use peak intensities are doing so with unknown levels of uncertainty and bias, potentially leading to spurious scientific outcomes.

As global climates shift, coastal systems experience changes that alter function within the tidal zone. However, it remains uncertain how changes in tidal extent and magnitude will alter coastal biogeochemical cycling. We present high‐frequency data collected in situ along two transects across a tidal creek and floodplain to capture how vertical and lateral connectivity changes act as biogeochemical control points. Using wavelet coherence analysis, we identified short periods of vertical tide–floodplain connectivity during spring tides followed by extended periods of floodplain isolation from tides. During a drier period, neap tides were linked to lateral creek–floodplain connectivity, detected by discharge of saline, oxygen‐depleted groundwater to the creek on ebb tides. We estimate that up to half of creek water throughout the tidal cycle was associated with floodplain drainage. From point measurements of carbon, nitrogen, and greenhouse gases along the creek–floodplain transect, we infer that lateral connectivity functions as a biogeochemically significant control point.

Determination of the median effective concentration (EC50) of Cu on Mytilus galloprovincialis larvae by diffusive gradient in thin films (DGT) has been shown to effectively reduce the need to consider dissolved organic carbon (DOC) concentration and quality. A standard toxicity test protocol was used to validate previously modeled protective effects, afforded to highly sensitive marine larvae by ligand competition, in 5 diverse site waters. The results demonstrate significant narrowing of M. galloprovincialis toxicological endpoints, where EC50s ranged from 3.74 to 6.67 μg/L as CDGT Cu versus 8.76 to 26.8 μg/L as dissolved Cu (CuDISS ) over a DOC range of 0.74 to 3.11 mg/L; Strongylocentrotus purpuratus EC50s were 10.5 to 19.3 μg/L as CDGT Cu versus 22.7 to 67.1 μg/L as CuDISS over the same DOC range. The quality of DOC was characterized by fluorescence excitation and emission matrices. The results indicate that the heterogeneity of competing Cu binding ligands, in common marine waters, minimizes the need for class determinations toward explaining the degree of protection. Using conservative assumptions, an M. galloprovincialis CDGT Cu EC50 of 3.7 µg/L and corresponding criterion maximum concentration CDGT Cu of 1.8 µg/L, for universal application by regulatory compliance-monitoring programs, are proposed as a superior approach toward both integration of dynamic water quality over effective exposure periods and quantification of biologically relevant trace Cu speciation. Environ Toxicol Chem 2020;39:873-881. © 2020 SETAC.

Numerous initiatives at the national, state, and local levels are focused on addressing the U.S. maternal health crisis. However, most efforts fail to center women’s voices and personal perspectives about pregnancy experiences and complications. This article describes the Illinois Maternal Health Digital Storytelling Project conducted by the University of Illinois at Chicago, in partnership with StoryCenter, a storytelling nonprofit organization based in Berkeley, California. The project aimed to elevate voices (stories) to complement other sources of data on maternal outcomes. We relied on partners to help recruit storytellers with a self-identified perinatal-related challenge. We screened interested individuals using a trauma-informed approach and a social worker provided storytellers with support during the project. Two groups participated in this project, one in 2021 and another in 2022, culminating with 10 digital stories. Both instances were conducted virtually and included group and individual skills-based sessions where storytellers learned to create and edit their digital stories. The storytellers own their digital stories and provided consent to include them in ongoing dissemination efforts. In September 2021, a webpage was launched to house the stories, and this resource is being shared widely. Evaluation efforts of the webpage are ongoing to understand how these digital stories are being used to inform maternal health efforts. Digital stories add richness to ongoing maternal health prevention work and may serve as a powerful tool to elicit understanding among providers, practitioners, and constituents.

Background and Objectives: Preexposure prophylaxis (PrEP) reduces HIV transmission among high-risk individuals. Yet, the HIV epidemic continues to expand among marginalized populations and America’s Southeastern states. Various barriers remain to PrEP uptake, namely provider knowledge and education. We sought to investigate residency training, competency, and prescribing of PrEP among population size. Additionally, we asked program directors to identify barriers to PrEP. Methods: We surveyed family medicine program directors as part of the Council of Academic Family Medicine Educational Research Alliance survey from January 2018 through February 2018. Results: Our survey questions had a 52.9% (276/522) response rate. No programs in rural communities less than 30,000 population (0/27) reported significant PrEP training for their residents; those in nonrural communities of at least 30,000 reported this training more frequently (41/246, 16.7%). Compared to Fischer expected values, the finding was statistically significant (P=.019); using a 75,000 population demarcation lowered significance (P=.192). We found programs that identify significant PrEP training also cite more PrEP prescribing within their practice (OR 7.27, P

Sea-level rise is one of the most critical challenges facing coastal ecosystems under climate change. Observations of elevated tree mortality in global coastal forests are increasing, but important knowledge gaps persist concerning the mechanism of salinity stress-induced nonhalophytic tree mortality. We monitored progressive mortality and associated gas exchange and hydraulic shifts in Sitka-spruce (Picea sitchensis) trees located within a salinity gradient under an ecosystem-scale change of seawater exposure in Washington State, USA. Percentage of live foliated crown (PLFC) decreased and tree mortality increased with increasing soil salinity during the study period. A strong reduction in gas exchange and xylem hydraulic conductivity (Ks) occurred during tree death, with an increase in the percentage loss of conductivity (PLC) and turgor loss point (πtlp). Hydraulic and osmotic shifts reflected that hydraulic function declined from seawater exposure, and dying trees were unable to support osmotic adjustment. Constrained gas exchange was strongly related to hydraulic damage at both stem and leaf levels. Significant correlations between foliar sodium (Na+) concentration and gas exchange and key hydraulic parameters (Ks, PLC, and πtlp) suggest that cellular injury related to the toxic effects of ion accumulation impacted the physiology of these dying trees. This study provides evidence of toxic effects on the cellular function that manifests in all aspects of plant functioning, leading to unfavourable osmotic and hydraulic conditions.

Wildfires are increasing in frequency, severity, and area burned in response to pervasive hotter and drier conditions, creating a multitude of negative consequences for aquatic ecosystems. Pyrogenic materials generated by wildfires are transported across terrestrial landscapes into inland waters, where approximately 10% of organic matter pools is comprised of black carbon. While recent work suggests pyrogenic organic matter (PyOM) is more bioavailable than indicated by traditional paradigms, the heterogeneity of PyOM pools generated through various feedstocks and combustion scenarios complicates our efforts to understand its bioavailability. Here, we use a mathematical model to predict the energy content, metabolic efficiency, and rate of aerobic decomposition of representative PyOM compounds. We compare these metrics to model outputs derived from measured natural organic matter in global surface waters and sediments to assess differences in bioavailability. We find that PyOM generally has a similar range of bioavailabilities to that of natural systems. However, phenols and black carbon (defined as highly condensed molecules with high solubility) have lower metabolic efficiency than most representative PyOM classes and natural organic matter pools, denoted by higher lambda and lower carbon use efficiency. Rates of aerobic metabolism of phenols and black carbon are also less negatively impacted by oxygen limitation than any other group. Overall, our work suggests that PyOM may be more bioavailable than previously thought and could be an unrecognized contributor to global C emissions as the prevalence of wildfires increases.

Plant litter chemistry is altered during decomposition but it remains unknown if these alterations, and thus the composition of residual litter, will change in response to climate. Selective microbial mineralization of litter components and the accumulation of microbial necromass can drive litter compositional change, but the extent to which these mechanisms respond to climate remains poorly understood. We addressed this knowledge gap by studying needle litter decomposition along a boreal forest climate transect. Specifically, we investigated how the composition and/or metabolism of the decomposer community varies with climate, and if that variation is associated with distinct modifications of litter chemistry during decomposition. We analyzed the composition of microbial phospholipid fatty acids (PLFAs) in the litter layer and measured natural abundance δ13CPLFA values as an integrated measure of microbial metabolisms. Changes in litter chemistry and δ13C values were measured in litterbag experiments conducted at each transect site. A warmer climate was associated with higher litter nitrogen concentrations as well as altered microbial community structure (lower fungi:bacteria ratios) and microbial metabolism (higher δ13CPLFA). Litter in warmer transect regions accumulated less aliphatic‐C (lipids, waxes) and retained more O‐alkyl‐C (carbohydrates), consistent with enhanced 13C‐enrichment in residual litter, than in colder regions. These results suggest that chemical changes during litter decomposition will change with climate, driven primarily by indirect climate effects (e.g., greater nitrogen availability and decreased fungi:bacteria ratios) rather than direct temperature effects. A positive correlation between microbial biomass δ13C values and 13C‐enrichment during decomposition suggests that change in litter chemistry is driven more by distinct microbial necromass inputs than differences in the selective removal of litter components. Our study highlights the role that microbial inputs during early litter decomposition can play in shaping surface litter contribution to soil organic matter as it responds to climate warming effects such as greater nitrogen availability.

Between the land and ocean, diverse coastal ecosystems transform, store, and transport material. Across these interfaces, the dynamic exchange of energy and matter is driven by hydrological and hydrodynamic processes such as river and groundwater discharge, tides, waves, and storms. These dynamics regulate ecosystem functions and Earth’s climate, yet global models lack representation of coastal processes and related feedbacks, impeding their predictions of coastal and global responses to change. Here, we assess existing coastal monitoring networks and regional models, existing challenges in these efforts, and recommend a path towards development of global models that more robustly reflect the coastal interface., Coastal systems are hotspots of ecological, geochemical and economic activity, yet their dynamics are not accurately represented in global models. In this Review, Ward and colleagues assess the current state of coastal science and recommend approaches for including the coastal interface in predictive models.

Soil moisture influences soil carbon dynamics, including microbial growth and respiration. The response of such ‘soil respiration’ to moisture changes is generally assumed to be linear and reversible, i.e. to depend only on the current moisture state. Current models thus do not account for antecedent soil moisture conditions when determining soil respiration or the available substrate pool. We conducted a laboratory incubation to determine how the antecedent conditions of drought and flood influenced soil organic matter (SOM) chemistry, bioavailability, and respiration. We sampled soils from an upland coastal forest, Beaver Creek, WA USA, and subjected them to drying and rewetting treatments. For the drying treatment, field moist soils were saturated and then dried to 75, 50, 35, and 5% saturation. In the rewetting treatment, field moist soils were air-dried and then rewet to 35, 50, 75, and 100% saturation. We measured respiration and water extractable organic carbon (WEOC) concentrations and used 1H-NMR and FT-ICR-MS to characterize the WEOC pool across the treatments. The drying vs. wetting treatment strongly influenced SOM bioavailability, as rewet soils (with antecedent drought) had greater WEOC concentrations and respiration fluxes compared to the drying soils (with antecedent flood). In addition, air-dry soils had the highest WEOC concentrations, and the NMR-resolved peaks showed a strong contribution of protein groups in these soils. Both NMR and FT-ICR-MS analyses indicated increased contribution of complex aromatic groups/molecules in the rewet soils, compared to the drying soils. We suggest that drying introduced organic matter into the WEOC pool via desorption of aromatic molecules and/or by microbial cell lysis, and this stimulated microbial mineralization rates. Our work indicates that even short-term shifts in antecedent moisture conditions can strongly influence soil C dynamics at the core scale. The predictive uncertainties in current soil models may be reduced by a more accurate representation of soil water and C persistence that includes a mechanistic and quantitative understanding of the impact of antecedent moisture conditions.

The most conventional and abundant tracers of biomass combustion in aerosol particles include potassium and biomarkers derived from thermally altered cellulose/hemicellulose (anhydrosugars) and lignin (methoxyphenols). However, little is known of the role biomass combustion plays as a particulate source of major plant polymers to the atmosphere. Here, concentrations of solvent-extractable anhydrosugars and methoxyphenols are compared to the yields of polymeric lignin oxidation products (LOPs) during a smoke plume event in Houston, Texas. Downwind aerosol samples (PM2.5) were collected surrounding a two-day wildfire in the McFaddin National Wildlife Refuge, 125 km southeast of Houston, which was 12-16 h directly downwind during the peak of the burn. Concentrations of all organic markers, potassium, and calcium increased by a factor of 2-13 within 1-2 days of the start of the fire and dropped to prefire levels 3 days after the peak event. Source signatures of anhydrosugars and methoxyphenols during the peak of the plume were identical to those of grass charcoals collected from the site, confirming the use of charcoals as end-members for source input reconstruction during atmospheric transport. An enrichment factor of 20 in the anhydrosugar to methoxyphenol ratio of aerosols versus charcoals can be explained partially by differences in degradation rate constants between the biomarker groups. LOPs comprised 73-91% of all lignin material in the aerosols, pointing to fires as major sources of primary biogenic aerosol particles in which lignin phenols occur predominantly in polymeric form.

Interpretive strategies for the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) include Wechsler's four-factor structure and the five-factor Cattell-Horn-Carroll (CHC) model. The frequency of profile occurrence and the contribution of demographic- and ability-related variables to their incidence are unknown. Current participants were 291 referrals (males = 134; female = 157) for neuropsychological evaluation with mean years for age and education of 34.94 (

A number of recent studies have documented that pyrogenic carbon (PyC) is an integral and significant proportion of DOM in worldwide rivers. This material originates from all fractions of the PyC continuum, from highly condensed PyC to more functionalized components that retain some structural identity of fuel molecules. Understanding the transfer of PyC to river systems is paramount for Arctic regions, given the projected increase in frequency and intensity of forest fires within these ecosystems. However, the environmental distribution and concentration of soluble and particulate PyC, parameters that govern the overall fate of PyC in aquatic systems, has so far been unstudied. Here, we analyze the concentration and phase distribution of the anhydrosugar biomarker levoglucosan, as a proxy for low-temperature PyC, in two high-latitude river systems: a small sub-Arctic Canadian river, the Great Whale River in northern Quebec, and the largest Arctic River, the Yenisei River in north-central Siberia. Low-temperature PyC, as estimated by levoglucosan concentrations, is exported predominantly in the dissolved phase. Peak export of low-temperature PyC occurs during the spring freshet period in both rivers. Seasonal variability of dissolved and particulate PyC export in each river elucidated that the export of PyC in the particulate and dissolved phases were temporally decoupled throughout the peak discharge events. While the present work confirms that levoglucosan is exported in particulate phase at a high enough level to enter sedimentary deposits and record historical wildfire signatures, as the phase distribution varies between rivers and during different flow regimes, spatial and temporal differences may affect the usage of levoglucosan as a PyC proxy in depositional settings.

To empirically-derive a new MMPI-2 sub-scale, the 13-item Cognitive Complaints Scale (CCS), as an embedded measure of symptom validity. This study hypothesized that mild traumatic brain injured subjects with financial incentives who failed performance validity tests (PVTs) would score significantly higher on the CCS compared to mild traumatic brain injured subjects with financial incentives who passed PVTs. Mild traumatic brain injured controls with no financial incentives were predicted to score lowest on the CCS.A known groups design was utilized as this design allows for the accurate classification of criterion groups.One hundred and fifty mild head-injured adults were assigned to one of three groups: the Failed Performance Validity (FPV) group, the Passed Performance Validity (PPV) group or a control group.An ANOVA revealed that the FPV group scored significantly higher on the CCS compared to the PPV group. Controls with no financial incentives scored lowest. A CCS cut-score of ≥12 discriminated between the FPV and PPV groups at a high level of specificity (94%).A dissociation between 'performance validity' and 'symptom validity' supports recommendations for the differential application of these descriptive terms. The CCS may be helpful to assess credibility of clinical presentation in situations where PVTs are absent.

We examined relationships between the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) General Ability Index (GAI) and Cognitive Proficiency Index (CPI) in two clinical samples. The mean pattern produced by 42 individuals with multiple sclerosis (MS) and 47 with traumatic brain injury (TBI) was the same, GAI > CPI. This pattern occurred in 61.9% and 78.7% of the protocols of patients with MS or TBI, respectively. The MS sample earned a significantly larger CPI mean than did patients with TBI. The group means did not differ on the GAI. Patients with TBI had significantly larger GAI-CPI discrepancy score means than those with MS. Receiver operating characteristics (ROC) analysis assessed the ability of GAI-CPI discrepancies to differentiate the samples. The area under curve (AUC) was 0.67, 95% [0.55, 0.78], which indicated low accuracy in terms of group classification.

A1 Introduction to the 8th Annual Conference on the Science of Dissemination and Implementation: Optimizing Personal and Population Health David Chambers1, Lisa Simpson2 1Division of Cancer Control and Population Sciences, National Cancer Institute, National Institutes of Health, Rockville, MD, 20850, USA; 2AcademyHealth, Washington, DC, 20036, USA For the second year in a row, we are pleased to be able to share the proceedings of the Annual Conference on the Science of Dissemination and Implementation in Health, a large meeting reflecting the expanding and evolving research field that seeks to optimize the use of evidence, interventions, and tools from health research within the myriad of settings where people receive health care, make health-related decisions, and increase knowledge of influences on the health of the population. We once again benefitted from a strong partnership, co-led by AcademyHealth and the National Institutes of Health (NIH), with co-sponsorship from the Agency for Healthcare Research and Quality (AHRQ), the Patient Centered Outcomes Research Institute (PCORI), the Robert Wood Johnson Foundation (RWJF), the US Department of Veterans Affairs (VA), and the WT Grant Foundation. In addition, we benefitted from the collaboration of staff from the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). NIH and AcademyHealth again co-led the program planning committee, which focused on the development of the plenary sessions, and convened a scientific advisory panel to suggest speakers and advise on the overall conference development. The planning committee identified four key areas around which to focus the plenary panels and keynote address. Dr. America Bracho, M.D., M.P.H., Executive Director of Latino Health Access in Orange County, California, spoke about the opportunities for implementation science to inform efforts to improve community health and engage underserved populations. The three plenary panels each focused on a significant future direction for dissemination and implementation (D & I) research: the interface between D&I science and population health, emerging opportunities for global implementation science, and the challenges around implementation of precision medicine. The plenary sessions were complemented by facilitated lunchtime discussions on the same three topics, which offered participants an opportunity to identify key research questions for each and brainstorm next steps. Synopses of the lunchtime discussions are included in this supplement. Given the overwhelming success of the 2014 conference and the large number of abstracts received in 2014 (660), the program planning committee identified eight program tracks for abstract submitters to respond to, and through which the concurrent sessions of the conference would be organized. These tracks—Behavioral Health, Big Data and Technology for Dissemination and Implementation Research, Clinical Care Settings, Global Dissemination and Implementation, Promoting Health Equity and Eliminating Disparities, Health Policy Dissemination and Implementation, Prevention and Public Health, and Models, Measures and Methods— were designed to enable conference participants to follow a consistent theme across the multiple sessions of the conference and form the structure of this supplement. The call for abstracts, including individual paper presentations, individual posters and panel presentations, resulted in 515 submissions, spread across the eight thematic tracks. Over one hundred reviewers devoted their time to ensuring a comprehensive and expert review, and reviews were conducted within each track and coordinated by the track leads. For the final program, 64 oral presentations, 12 panels, and 263 posters were presented over the two-day meeting. Slides for the oral presentations and panels (with the agreement of the authors) were posted on the conference website (http://diconference.academyhealth.org/archives/2015archives) and all abstracts were included on the conference webapp (https://academyhealth.confex.com/academyhealth/2015di/meetingapp.cgi). This supplement has compiled the abstracts for presented papers, panel sessions, and lunchtime discussions from the 8th Annual Meeting on the Science of Dissemination and Implementation in Health: Optimizing Personal and Population Health. We are pleased to have the abstracts from the conference together in one volume once again, and look forward to the 9th Annual meeting, scheduled for December in Washington, D.C.

A fundamental understanding of biodegradability is central to elucidating the role(s) of pyrogenic organic matter (PyOM) in biogeochemical cycles. Since microbial community and ecosystem dynamics are driven by net energy flows, then a quantitative assessment of energy value versus energy requirement for oxidation of PyOM should yield important insights into their biodegradability. We used bomb calorimetry, stepwise isothermal thermogravimetric analysis (isoTGA), and 5-year in situ bidegradation data to develop energy-biodegradability relationships for a suite of plant- and manure-derived PyOM (n = 10). The net energy value (ΔE) for PyOM was between 4.0 and 175 kJ mol(-1); with manure-derived PyOM having the highest ΔE. Thermal-oxidation activation energy (Ea) requirements ranged from 51 to 125 kJ mol(-1), with wood-derived PyOM having the highest Ea requirements. We propose a return-on-investment (ROI) parameter (ΔE/Ea) for differentiating short-to-medium term biodegradability of PyOM and deciphering if biodegradation will most likely proceed via cometabolism (ROI1) or direct metabolism (ROI ≥ 1). The ROI-biodegradability relationship was sigmoidal with higher biodegradability associated with PyOM of higher ROI; indicating that microbes exhibit a higher preference for "high investment value" PyOM.

Graham Wilmer writes a provocative book, Conspiracy of Faith: Fighting for Justice after Child Abuse, describing his journey through life of being a survivor of child sexual abuse. He takes readers...

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. Biomass burning produces a spectrum of thermally altered materials that releases pyrogenic carbon (PyC) to terrestrial, atmospheric, and aquatic systems. Most studies focus on the refractory end of the PyC spectrum, derived from middle- to high-temperature combustion. Low-temperature PyC is produced during wildfires and has been found to be particularly labile and water soluble. Here we find that in each of the major Siberian watersheds, low-temperature fire-derived biomarkers are present in detectable concentrations during all flow regimes of the 2004–2006 sampling period, confirming that PyC is an intrinsic component of the dissolved organic carbon (DOC) pool mobilized by hydrologic events. Gymnosperm combustion, from the southern portions of these watersheds, is the primary source of this Py-DOC input. Using first-order degradation rates and transit times of water through these rivers, about half of the total estimated flux of this material may be remineralized during transport from fire source to river mouth (20–40 days), demonstrating the input of a labile source of PyC to these watersheds.

Summer 2012 was one of the extreme wildfire years in Siberia. At the surface air monitoring station “ZOTTO” (60°48′N, 89°21′E, 114 m a.s.l.) in Central Siberia we observed biomass burning (BB) influence on the ongoing atmospheric measurements within more than 50 % of the time in June-July 2012 that indicates a 30 times greater wildfire signal compared to previously reported ordinary biomass burning signature for the study area. While previous studies thoroughly estimated a relative input of BB into aerosol composition (i.e. size distribution, physical and optical parameters etc.) at ZOTTO, in this paper we characterize the source apportionment of the smoke aerosols with molecular tracer techniques from large-scale wildfires occurred in 2012 in the two prevailing types of Central Siberian ecosystems: complexes of pine forests and bogs and dark coniferous forests. Wildfires in the selected ecosystems are highly differed by their combustion phase (flaming/smoldering), the type of fire (crown/ground), biomass fuel, and nature of soil that greatly determines the smoke particle composition. Anhydrosugars (levoglucosan and its isomers) and lignin phenols taken as indicators of the sources and the state of particulate matter (PM) inputs in the specific fire plumes were used as powerful tools to compare wildfires in different environmental conditions and follow the role and contribution of different sources of terrestrial organic matter in the transport of BB pollutants into the pristine atmosphere of boreal zone in Central Siberia.

Declines in IQ scores with advancing age have been observed in each successive revision of the Wechsler Intelligence Scales. This study examined age-related changes on the fourth edition of the Wechsler Adult Intelligence Scale and compared these to the effects seen on the 1955, 1981, and 1997 standardizations of the scales. The most pronounced declines were in measures of processing speed and nonverbal reasoning. Declines in nonverbal reasoning were similar on timed and un-timed measures. Verbal abilities remained relatively stable across the life span. General intelligence as assessed by the Full Scale IQ was reduced about 1 SD by age 75 when corrections for age were removed. Age-related declines have become less pronounced since 1955, particularly on measures of processing speed. This effect was essentially linear, unrelated to concurrent IQ increases in the general population, and paralleled a 9-year increase in life expectancy during this time period.