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There are significant concerns that COVID-19-related disruptions in routine health care will reverse the gains made over the past 2 decades in reducing maternal and under-5 mortality in low- and middle-income countries. The objective of this study was to examine the extent of disruptions in community-based maternal and child health services and explore community perceptions and experiences with health care use in the year following the start of the COVID-19 pandemic in one district in northern Togo, West Africa. This study included analysis of multiple types of data including: (1) routine health management information system data from 18 public sector health centers, (2) programmatic data collected through an integrated health center- and community-based primary care program at 5 health centers, and (3) semi-structured interviews with health center managers, community health workers (CHWs), and community members at those 5 health centers. We found only short-term declines in service utilization coinciding with the COVID-19 pandemic and no decline in the delivery of community-based care by CHWs. Qualitative data were consistent with the quantitative results, reporting sustained use of health-care services. Multilevel factors related to the continued provision of care during the COVID-19 pandemic included regular and clear communication from CHWs as trusted community sources, risk minimization at the health-center level, continued provision of community-based care by CHWs, and collaboration between community leaders and health-care workers to limit COVID-19 transmission. Findings demonstrate resiliency of an integrated primary care system when equipped with an adequately trained, supervised, and supplied health workforce, implementation of infection prevention and control measures, communication by trusted community sources, and adaptations to health-care delivery that enable the continued provision of care.

Concerns over climate change have necessitated a rethinking of our transportation infrastructure. One possible alternative to carbon-polluting fossil fuels is biofuels produced by engineered microorganisms that use a renewable carbon source. Two biofuels, ethanol and biodiesel, have made inroads in displacing petroleum-based fuels, but their uptake has been limited by the amounts that can be used in conventional engines and by their cost. Advanced biofuels that mimic petroleum-based fuels are not limited by the amounts that can be used in existing transportation infrastructure but have had limited uptake due to costs. In this Review, we discuss engineering metabolic pathways to produce advanced biofuels, challenges with substrate and product toxicity with regard to host microorganisms and methods to engineer tolerance, and the use of functional genomics and machine learning approaches to produce advanced biofuels and prospects for reducing their costs.

Assigning a functional role to a microorganism has historically relied on cultivation of isolates or detection of environmental genome-based biomarkers using a posterioriknowledge of function. However, the emerging field of function-driven single-cell genomics aims to expand this paradigm by identifying and capturing individual microbes based on their in situ functions or traits. To identify and characterize yet uncultivated microbial taxa involved in cellulose degradation, we developed and benchmarked a function-driven single-cell screen, which we applied to a microbial community inhabiting the Great Boiling Spring (GBS) Geothermal Field, northwest Nevada. Our approach involved recruiting microbes to fluorescently labeled cellulose particles, and then isolating single microbe-bound particles via fluorescence-activated cell sorting. The microbial community profiles prior to sorting were determined via bulk sample 16S rRNA gene amplicon sequencing. The flow-sorted cellulose-bound microbes were subjected to whole genome amplification and shotgun sequencing, followed by phylogenetic placement. Next, putative cellulase genes were identified, expressed and tested for activity against derivatives of cellulose and xylose. Alongside typical cellulose degraders, including members of the Actinobacteria, Bacteroidetes, and Chloroflexi, we found divergent cellulases encoded in the genome of a recently described candidate phylum from the rare biosphere, Goldbacteria, and validated their cellulase activity. As this genome represents a species-level organism with novel and phylogenetically distinct cellulolytic activity, we propose the name Candidatus‘Cellulosimonas argentiregionis’. We expect that this function-driven single-cell approach can be extended to a broad range of substrates, linking microbial taxonomy directly to in situ function.

Assigning a functional role to a microorganism has historically relied on cultivation of isolates or detection of environmental genome-based biomarkers using a posterioriknowledge of function. However, the emerging field of function-driven single-cell genomics aims to expand this paradigm by identifying and capturing individual microbes based on their in situ functions or traits. To identify and characterize yet uncultivated microbial taxa involved in cellulose degradation, we developed and benchmarked a function-driven single-cell screen, which we applied to a microbial community inhabiting the Great Boiling Spring (GBS) Geothermal Field, northwest Nevada. Our approach involved recruiting microbes to fluorescently labeled cellulose particles, and then isolating single microbe-bound particles via fluorescence-activated cell sorting. The microbial community profiles prior to sorting were determined via bulk sample 16S rRNA gene amplicon sequencing. The flow-sorted cellulose-bound microbes were subjected to whole genome amplification and shotgun sequencing, followed by phylogenetic placement. Next, putative cellulase genes were identified, expressed and tested for activity against derivatives of cellulose and xylose. Alongside typical cellulose degraders, including members of the Actinobacteria, Bacteroidetes, and Chloroflexi, we found divergent cellulases encoded in the genome of a recently described candidate phylum from the rare biosphere, Goldbacteria, and validated their cellulase activity. As this genome represents a species-level organism with novel and phylogenetically distinct cellulolytic activity, we propose the name Candidatus‘Cellulosimonas argentiregionis’. We expect that this function-driven single-cell approach can be extended to a broad range of substrates, linking microbial taxonomy directly to in situ function.

IMPORTANCE: Myelofibrosis is a hematologic malignancy characterized by splenomegaly and debilitating symptoms. Thrombocytopenia is a poor prognostic feature and limits use of Janus kinase 1 (JAK1)/Janus kinase 2 (JAK2) inhibitor ruxolitinib. OBJECTIVE: To compare the efficacy and safety of JAK2 inhibitor pacritinib with that of best available therapy (BAT), including ruxolitinib, in patients with myelofibrosis and thrombocytopenia. DESIGN, SETTING, AND PARTICIPANTS: For this phase 3 randomized international multicenter study—the PERSIST-2 study—of pacritinib vs BAT, 311 patients with myelofibrosis and platelet count 100 × 109/L or less were recruited for analysis. Crossover from BAT was allowed after week 24 or for progression of splenomegaly. INTERVENTIONS: Patients were randomized 1:1:1 to pacritinib 400 mg once daily, pacritinib 200 mg twice daily, or BAT. MAIN OUTCOMES AND MEASURES: Coprimary end points were rates of patients achieving 35% or more spleen volume reduction (SVR) and 50% or more reduction in total symptom score (TSS) at week 24. Efficacy analyses were performed on the intention-to-treat efficacy population, comprising all patients with a randomization date allowing for week 24 data. RESULTS: Overall, 311 patients (mean [SD] age, 63.70 [9.08] years; 171 men [55%] and 140 women [45%]) were included in the study; 149 patients (48%) had prior ruxolitinib. The most common BAT was ruxolitinib (44 patients [45%]); 19 patients (19%) received watchful-waiting only. The intention-to-treat efficacy population included 75 patients randomized to pacritinib once daily; 74, pacritinib twice daily, and 72, BAT. Pacritinib (arms combined) was more effective than BAT for 35% or more SVR (27 patients [18%] vs 2 patients [3%]; P = .001) and had a nonsignificantly greater rate of 50% or more reduction in TSS (37 patients [25%] vs 10 patients [14%]; P = .08). Pacritinib twice daily led to significant improvements in both end points over BAT (≥35% SVR: 16 patients [22%] vs 2 patients [3%]; P = .001; ≥50% reduction in TSS: 24 patients [32%] vs 10 patients [14%]; P = .01). Clinical improvement in hemoglobin and reduction in transfusion burden were greatest with pacritinib twice daily. For pacritinib once daily, pacritinib twice daily, and BAT, the most common (>10%) grade 3 or 4 adverse events were thrombocytopenia (32 patients [31%], 34 patients [32%], 18 patients [18%]), and anemia (28 patients [27%], 23 patients [22%], 14 patients [14%]). In the pacritinib once daily, twice daily, and BAT arms, discontinuation owing to adverse events occurred in 15 patients (14%), 10 patients (9%), and 4 patients (4%). CONCLUSIONS AND RELEVANCE: In patients with myelofibrosis and thrombocytopenia, including those with prior anti-JAK therapy, pacritinib twice daily was more effective than BAT, including ruxolitinib, for reducing splenomegaly and symptoms. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02055781

Methods for assembly, taxonomic profiling and binning are key to interpreting metagenome data, but a lack of consensus about benchmarking complicates performance assessment. The Critical Assessment of Metagenome Interpretation (CAMI) challenge has engaged the global developer community to benchmark their programs on highly complex and realistic data sets, generated from ∼700 newly sequenced microorganisms and ∼600 novel viruses and plasmids and representing common experimental setups. Assembly and genome binning programs performed well for species represented by individual genomes but were substantially affected by the presence of related strains. Taxonomic profiling and binning programs were proficient at high taxonomic ranks, with a notable performance decrease below family level. Parameter settings markedly affected performance, underscoring their importance for program reproducibility. The CAMI results highlight current challenges but also provide a roadmap for software selection to answer specific research questions.

Background: The conversion of biomass to fuels and chemicals is an important technology to replace petroleum as a transportation fuel which will ease climate effects of burning fossil fuels. Recent advances in cellulosic ethanol production have enabled the establishment of commercial scale plants that produce ethanol for transportation fuel. Thermotolerant cellulase enzymatic mixtures from thermophilic fungi are an attractive alternative to currently available commercial cellulase cocktails. Methods: Thermoascus aurantiacus is a thermophilic ascomycete fungus within the order of Eurotiales that was first isolated by Miehe in 1907. Strains of T. aurantiacus have been isolated from a variety of terrestrial environments, which all have been shown to be homothallic and produce large amounts of ascopores with an optimal growth temperature at ~50?C. T. aurantiacus secretes high titers of cellulases (>1 g/L) when grown in the presence of plant biomass substrates and produces a remarkably simple cellulase mixture consisting of GH7 cellobiohydrolase, GH5 endoglucanase, AA9 lytic polysaccharide monooxygenase and GH3 beta-glucosidase. Results: In this mini-review, the biology and enzymology underlying cellulase production are described and an approach to developing T. aurantiacus strains for industrial cellulase production is outlined. Conclusion: The properties of T. aurantiacus and the thermotolerant cellulase mixture it produces may be the basis for new enzymatic cocktails to produce sugars from plant biomass that can be converted to biofuels.

Available therapies for myelofibrosis can exacerbate cytopenias and are not indicated for patients with severe thrombocytopenia. Pacritinib, which inhibits both JAK2 and FLT3, induced spleen responses with limited myelosuppression in phase 1/2 trials. We aimed to assess the efficacy and safety of pacritinib versus best available therapy in patients with myelofibrosis irrespective of baseline cytopenias.

The article discusses the use of viral, or socially contagious, social media in information warfare, including the terrorist organization the Islamic State in Iraq and Syria's (ISIS's) propaganda through social media on the Internet. An overview of the Russian and Chinese government's information warfare is provided.

Systemic lupus erythematous (SLE) is a chronic autoimmune disease associated with genetic and environmental risk factors. However, the extent to which genetic risk is causally associated with disease activity is unknown. We utilized longitudinal-targeted maximum likelihood estimation to estimate the causal association between a genetic risk score (GRS) comprising 41 established SLE variants and clinically important disease activity as measured by the validated Systemic Lupus Activity Questionnaire (SLAQ) in a multiethnic cohort of 942 individuals with SLE. We did not find evidence of a clinically important SLAQ score difference (>4.0) for individuals with a high GRS compared with those with a low GRS across nine time points after controlling for sex, ancestry, renal status, dialysis, disease duration, treatment, depression, smoking and education, as well as time-dependent confounding of missing visits. Individual single-nucleotide polymorphism (SNP) analyses revealed that 12 of the 41 variants were significantly associated with clinically relevant changes in SLAQ scores across time points eight and nine after controlling for multiple testing. Results based on sophisticated causal modeling of longitudinal data in a large patient cohort suggest that individual SLE risk variants may influence disease activity over time. Our findings also emphasize a role for other biological or environmental factors.

It is well known that trace element sensitivity in electron probe microanalysis (EPMA) is limited by intrinsic random variation in the X-ray continuum background and weak signals at low concentrations. The continuum portion of the background is produced by deceleration of the electron beam by the Coulombic field of the specimen atoms. In addition to the continuum, the background also includes interferences from secondary emission lines, “holes” in the continuum from secondary Bragg diffraction, non-linear curvature of the wavelength-dispersive spectrometer (WDS) continuum and other background artifacts. Typically, the background must be characterized with sufficient precision (along with the peak intensity of the emission line of interest, to obtain the net intensity for subsequent quantification), to attain reasonable accuracy for quantification of the elements of interest. Traditionally we characterize these background intensities by measuring on either side of the emission line and interpolate the intensity underneath the peak to obtain the net intensity. Instead, by applying the mean atomic number (MAN) background calibration curve method proposed in this paper for the background intensity correction, such background measurement artifacts are avoided through identification of outliers within a set of standards. We divide the analytical uncertainty of the MAN background calibration between precision errors and accuracy errors. The precision errors of the MAN background calibration are smaller than direct background measurement, if the mean atomic number of the sample matrix is precisely known. For a simple matrix and a suitable blank standard, a high-precision blank correction can offset the accuracy component of the MAN uncertainty. Use of the blank-corrected-MAN background calibration can further improve our measurement precision for trace elements compared to traditional off-peak measurements because the background determination is not limited by continuum X-ray counting statistics. For trace element mapping of a simple matrix, the background variance due to major element heterogeneity is exceedingly small and high-precision two-dimensional background correction is possible.

Recent studies have expanded the phylum Chlorobi, demonstrating that the green sulfur bacteria (GSB), the original cultured representatives of the phylum, are a part of a broader lineage whose members have more diverse metabolic capabilities that overlap with members of the phylum Bacteroidetes. The 16S rRNA gene of an uncultivated clone, OPB56, distantly related to the phyla Chlorobi and Bacteroidetes, was recovered from Obsidian Pool in Yellowstone National Park; however, the detailed phylogeny and function of OPB56 and related clones have remained unknown. Culturing of thermophilic bacterial consortia from compost by adaptation to grow on ionic-liquid pretreated switchgrass provided a consortium in which one of the most abundant members, NICIL-2, clustered with OPB56-related clones. Phylogenetic analysis using the full-length 16S rRNA gene from NICIL-2 demonstrated that it was part of a monophyletic clade, referred to as OPB56, distinct from the Bacteroidetes and Chlorobi. A near complete draft genome (>95% complete) was recovered from metagenomic data from the culture adapted to grow on ionic-liquid pretreated switchgrass using an automated binning algorithm, and this genome was used for marker gene-based phylogenetic analysis and metabolic reconstruction. Six additional genomes related to NICIL-2 were reconstructed from metagenomic data sets obtained from thermal springs at Yellowstone National Park and Nevada Great Boiling Spring. In contrast to the 16S rRNA gene phylogenetic analysis, protein phylogenetic analysis was most consistent with the clustering of the Chlorobea, Ignavibacteria and OPB56 into a single phylum level clade. Metabolic reconstruction of NICIL-2 demonstrated a close linkage with the class Ignavibacteria and the family Rhodothermaceae, a deeply branching Bacteroidetes lineage. The combined phylogenetic and functional analysis of the NICIL-2 genome has refined the membership in the phylum Chlorobi and emphasized the close evolutionary and metabolic relationship between the phyla Chlorobi and the Bacteroidetes.

Recent studies have expanded the phylum Chlorobi, demonstrating that the green sulfur bacteria (GSB), the original cultured representatives of the phylum, are a part of a broader lineage whose members have more diverse metabolic capabilities that overlap with members of the phylum Bacteroidetes. The 16S rRNA gene of an uncultivated clone, OPB56, distantly related to the phyla Chlorobi and Bacteroidetes, was recovered from Obsidian Pool in Yellowstone National Park; however, the detailed phylogeny and function of OPB56 and related clones have remained unknown. Culturing of thermophilic bacterial consortia from compost by adaptation to grow on ionic-liquid pretreated switchgrass provided a consortium in which one of the most abundant members, NICIL-2, clustered with OPB56-related clones. Phylogenetic analysis using the full-length 16S rRNA gene from NICIL-2 demonstrated that it was part of a monophyletic clade, referred to as OPB56, distinct from the Bacteroidetes and Chlorobi. A near complete draft genome (>95% complete) was recovered from metagenomic data from the culture adapted to grow on ionic-liquid pretreated switchgrass using an automated binning algorithm, and this genome was used for marker gene-based phylogenetic analysis and metabolic reconstruction. Six additional genomes related to NICIL-2 were reconstructed from metagenomic data sets obtained from thermal springs at Yellowstone National Park and Nevada Great Boiling Spring. In contrast to the 16S rRNA gene phylogenetic analysis, protein phylogenetic analysis was most consistent with the clustering of the Chlorobea, Ignavibacteriaand OPB56 into a single phylum level clade. Metabolic reconstruction of NICIL-2 demonstrated a close linkage with the class Ignavibacteriaand the family Rhodothermaceae, a deeply branching Bacteroidetes lineage. The combined phylogenetic and functional analysis of the NICIL-2 genome has refined the membership in the phylum Chlorobi and emphasized the close evolutionary and metabolic relationship between the phyla Chlorobi and the Bacteroidetes.

Folate deficiency during early embryonic development constitutes a risk factor for neural tube defects and potentially for childhood leukemia via unknown mechanisms. We tested whether folate consumption during the 12 months prior to conception induced DNA methylation modifications at birth in healthy neonates with a genome-wide and agnostic approach. We hypothesized that DNA methylation in genes involved in neural tube development and/or cancer susceptibility would be affected by folate exposure. We retrospectively assessed folate exposure at the time of conception by food-frequency questionnaires administered to the mothers of 343 healthy newborns. We measured genome-wide DNA methylation from neonatal blood spots. We implemented a method based on bootstrap resampling to decrease false-positive findings. Folate was inversely associated with DNA methylation throughout the genome. Among the top folate-associated genes that were replicated in an independent Gambian study were TFAP2A, a gene critical for neural crest development, STX11, a gene implicated in acute myeloid leukemia, and CYS1, a candidate gene for cystic kidney disease. Reduced periconceptional folate intake was associated with increased methylation and, in turn, decreased gene expression at these 3 loci. The top folate-sensitive genes defined by their associated CpG sites were enriched for numerous transcription factors by Gene Set Enrichment Analysis, including those implicated in cancer development (e.g., MYC-associated zinc finger protein). The influence of estimated periconceptional folate intake on neonatal DNA methylation levels provides potential mechanistic insights into the role of this vitamin in the development of neural tube defects and childhood cancers.

Bacterial extracellular metal respiration, as carried out by members of the genus Geobacter, is of interest for applications including microbial fuel cells and bioremediation. Geobacter bemidjiensisis the major species whose growth is stimulated during groundwater amendment with acetate. We have carried out label-free proteomics studies of G. bemidjiensisgrown with acetate as the electron donor and either fumarate, ferric citrate, or one of two hydrous ferric oxide mineral types as electron acceptor. The major class of proteins whose expression changes across these conditions is c-type cytochromes, many of which are known to be involved in extracellular metal reduction in other, better-characterized Geobacterspecies. Some proteins with multiple homologues in G. bemidjiensis(OmcS, OmcB) had different expression patterns than observed for their G. sulfurreducenshomologues under similar growth conditions. We also compared the proteome from our study to a prior proteomics study of biomass recovered from an aquifer in Colorado, where the microbial community was dominated by strains closely related to G. bemidjiensis. We detected an increased number of proteins with functions related to motility and chemotaxis in the Colorado field samples compared to the laboratory samples, suggesting the importance of motility for in situ extracellular metal respiration.

The article discusses the new technologies developed by terrorist organizations, as well as the those developed by the U.S. to counter them as of February 2015. Among the new technologies from extremists are the land-based airplane bomb, the transforming cargo container, and the physical online assaults. The technological deterrents by the U.S. include the predictive bomb detection system, the imitation smuggling submarine, and the unbreakable Wi-Fi system.

Sap flow gages are used to estimate plant transpiration (an indirect form of soil water loss), but relatively few studies compare transpiration with other measures of soil water loss. The purpose of this study was to compare two landscape positions for transpiration (T) from sap flow measurements, soil water changes estimated by daily neutron probe readings, and evapotranspiration (ET) determined via eddy covariance and associated microclimate measurements. Monitoring at backslope and toeslope positions occurred for 2 wk during the corn (Zea maysL.) early reproductive stage. Evaporation from soil (E) and potential ET were calculated from microclimate measurements. The T from sap flow measurements plus calculated soil E was significantly higher at the backslope position than the toeslope position. Grain yields were within 3% (9020 vs. 8774 kg ha−1) for the toeslope and backslope positions. At the backslope position, crop development was delayed at the milk stage and leaf area index was larger compared with corn at the toeslope position. For July 18th through August 4th, the water table was 0.65 to 0.85 m deep at the toeslope position but 1.70 to 2.28 m deep at the backslope position. Higher water table depths at the toeslope position would supply extra water during dry times compared with the backslope position but could also have caused low temperature stress early in the season. The backslope faced south and could have experienced higher wind speed causing water stress during dry periods. The mid to late 2011 growing season was dry enough to detect landscape position effects.

We present an X-ray diffraction and multi-nuclear (2H and 43Ca) NMR study of Ca-exchanged hectorite (a smectite clay) that provides important new insight into molecular behavior at the smectite-H2O interface. Variable-temperature 43Ca MAS NMR and controlled humidity XRD indicate that Ca2+occurs as proximity-restricted outer-sphere hydration complexes between -120 and +25 °C in a two-layer hydrate and at T ≤ -50 °C in a 2:1 water/solid paste. Changes in the 43Ca NMR peak width and position with temperature are more consistent with diffusion-related processes than with dynamics involving metal-surface interactions such as site exchange. The 2H NMR signal between -50 and +25 °C for a two-layer hydrate of Ca-hectorite is similar to that of Na- and other alkali metal hectorites and represents 2H2O molecules experiencing anisotropic motion describable using the 2H C2/C3jump model we proposed previously. 2H T1relaxation results for Ca- and Na-hectorite are well fit with a fast-exchange limit, rotational diffusion model for 2H2O dynamics, yielding GHz-scale rotational reorientation rates compatible with the C3component of the C2/C3hopping model. The apparent activation energy for 2H2O rotational diffusion in the two-layer hydrate is greater for Ca-hectorite than Na-hectorite (25.1 vs. 21.1 kJ/mol), consistent with the greater affinity of Ca2+for H2O. The results support the general principle that the dynamic mechanisms of proximity-restricted H2O are only weakly influenced by the cation in alkali metal and alkaline earth metal smectites and provide critical evidence that the NMR resonances of charge-balancing cations in smectites become increasingly influenced by diffusion-like dynamic processes at low temperatures as the charge density of the unhydrated cation increases.

AbstractWe present an X-ray diffraction and multi-nuclear (2H and 43Ca) NMR study of Ca-exchanged hectorite (a smectite clay) that provides important new insight into molecular behavior at the smectite-H2O interface. Variable-temperature 43Ca MAS NMR and controlled humidity XRD indicate that Ca2+occurs as proximity-restricted outer-sphere hydration complexes between -120 and +25 °C in a two-layer hydrate and at T = -50 °C in a 2:1 water/solid paste. Changes in the 43Ca NMR peak width and position with temperature are more consistent with diffusion-related processes than with dynamics involving metal-surface interactions such as site exchange. The 2H NMR signal between -50 and +25 °C for a two-layer hydrate of Ca-hectorite is similar to that of Na- and other alkali metal hectorites and represents 2H2O molecules experiencing anisotropic motion describable using the 2H C2/C3jump model we proposed previously. 2H T1relaxation results for Ca- and Na-hectorite are well fit with a fast-exchange limit, rotational diffusion model for 2H2O dynamics, yielding GHz-scale rotational reorientation rates compatible with the C3component of the C2/C3hopping model. The apparent activation energy for 2H2O rotational diffusion in the two-layer hydrate is greater for Ca-hectorite than Na-hectorite (25.1 vs. 21.1 kJ/mol), consistent with the greater affinity of Ca2+for H2O. The results support the general principle that the dynamic mechanisms of proximity-restricted H2O are only weakly influenced by the cation in alkali metal and alkaline earth metal smectites and provide critical evidence that the NMR resonances of charge-balancing cations in smectites become increasingly influenced by diffusion-like dynamic processes at low temperatures as the charge density of the unhydrated cation increases.

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Corn (Zea maysL.) stover has been identified as an important feedstock for biofuel production but its removal will likely increase soil erosion. To address this issue 35 species of grasses and legumes were evaluated as potential perennial ground covers (PGCs) in corn. Selection of species encompassed both C3 and C4 species with a wide range of developmental and morphological features. The objectives were to (i) identify species that could support a high level of corn production while requiring minimal management and (ii) identify morphological traits and growth habits of suitable entries as PGC. Over the 3‐yr study period species with slow growing and spreading habits were more conducive to corn production, even though these PGCs still caused an average 23% reduction in corn grain yield. Meadow fescue (Festuca pratensisHuds.), sheep fescue (Festuca ovinaL.), Canada bluegrass (Poa compressaL.), fowl bluegrass (Poa palustrisL.), and colonial bentgrass (Agrostis capillarisL.) were identified as suitable PGC species. These species were generally shorter and slower to spread into the corn rows compared with other, more aggressive species. Based on these observations an ideotype for future PGC species should be low growing, clump forming, and shade tolerant and have delayed green‐up in the spring.

Cardiotoxicity from the antitumor anthracycline doxorubicin correlates with doxorubicin cardiac levels, redox activation to superoxide anion (O2._) and hydrogen peroxide (H2O2), and formation of the long-lived secondary alcohol metabolite doxorubicinol. Cardiotoxicity may first manifest during salvage therapy with other drugs, such as the anthracenedione mitoxantrone. Minimal evidence for cardiotoxicity in anthracycline-pretreated patients with refractory-relapsed non-Hodgkin lymphoma was observed with the novel anthracenedione pixantrone. We characterized whether pixantrone and mitoxantrone caused different effects on doxorubicin levels, redox activation, and doxorubicinol formation. Pixantrone and mitoxantrone were probed in a validated ex vivo human myocardial strip model that was either doxorubicin-naïve or preliminarily subjected to doxorubicin loading and washouts to mimic doxorubicin treatment and elimination in the clinical setting. In doxorubicin-naïve strips, pixantrone showed higher uptake than mitoxantrone; however, neither drug formed O2._or H2O2. In doxorubicin-pretreated strips, neither pixantrone nor mitoxantrone altered the distribution and clearance of residual doxorubicin. Mitoxantrone showed an unchanged uptake and lacked effects on doxorubicin levels, but synergized with doxorubicin to form more O2._and H2O2, as evidenced by O2._-dependent inactivation of mitochondrial aconitase or mitoxantrone oxidation by H2O2-activated peroxidases. In contrast, pixantrone uptake was reduced by prior doxorubicin exposure; moreover, pixantrone lacked redox synergism with doxorubicin, and formed an N-dealkylated product that inhibited metabolism of residual doxorubicin to doxorubicinol. Redox inactivity and inhibition of doxorubicinol formation correlate with the cardiac safety of pixantrone in doxorubicin-pretreated patients. Redox inactivity in the face of high cardiac uptake suggests that pixantrone might also be safe in doxorubicin-naïve patients.

Cardiotoxicity from the antitumor anthracycline doxorubicin correlates with doxorubicin cardiac levels, redox activation to superoxide anion (O(2)(._)) and hydrogen peroxide (H(2)O(2)), and formation of the long-lived secondary alcohol metabolite doxorubicinol. Cardiotoxicity may first manifest during salvage therapy with other drugs, such as the anthracenedione mitoxantrone. Minimal evidence for cardiotoxicity in anthracycline-pretreated patients with refractory-relapsed non-Hodgkin lymphoma was observed with the novel anthracenedione pixantrone. We characterized whether pixantrone and mitoxantrone caused different effects on doxorubicin levels, redox activation, and doxorubicinol formation. Pixantrone and mitoxantrone were probed in a validated ex vivo human myocardial strip model that was either doxorubicin-naïve or preliminarily subjected to doxorubicin loading and washouts to mimic doxorubicin treatment and elimination in the clinical setting. In doxorubicin-naïve strips, pixantrone showed higher uptake than mitoxantrone; however, neither drug formed O(2)(._) or H(2)O(2). In doxorubicin-pretreated strips, neither pixantrone nor mitoxantrone altered the distribution and clearance of residual doxorubicin. Mitoxantrone showed an unchanged uptake and lacked effects on doxorubicin levels, but synergized with doxorubicin to form more O(2)(._) and H(2)O(2), as evidenced by O(2)(._)-dependent inactivation of mitochondrial aconitase or mitoxantrone oxidation by H(2)O(2)-activated peroxidases. In contrast, pixantrone uptake was reduced by prior doxorubicin exposure; moreover, pixantrone lacked redox synergism with doxorubicin, and formed an N-dealkylated product that inhibited metabolism of residual doxorubicin to doxorubicinol. Redox inactivity and inhibition of doxorubicinol formation correlate with the cardiac safety of pixantrone in doxorubicin-pretreated patients. Redox inactivity in the face of high cardiac uptake suggests that pixantrone might also be safe in doxorubicin-naïve patients.

Constraints to maize (Zea maysL.) stover biomass harvest may be mitigated by using a living mulch (LM) to offset C exports and control soil erosion. Living mulches can compete with the main crop for resources. The objective of this research was to quantify competitive effects of LM management systems grown in continuous maize with stover removal. Maize was planted into creeping red fescue (CF) (Festuca rubraL.), Kentucky bluegrass (KB) (Poa pratensisL.), and a mixture of CF and white clover (Trifolium repensL.) (MX) LMs in 2008, 2009, and 2010 near Ames, IA. Management treatments were fall strip‐tillage (ST) and no‐tillage (NT), with either a pre‐planting paraquat burn‐down followed by two glyphosate bands (PQ) or glyphosate bands only (GLY). Kentucky bluegrass PQ ST produced similar grain yields (11,230 kg ha−1) all 3 yr as the no LM control (11,810 kg ha−1) with a harvest index (HI) of 0.55 compared to 0.52 in the control, averaged across years. The control produced greater stover dry matter (SDM) (10,110 kg ha−1) 2 of the 3 yr compared to KB PQ ST (8600 kg ha−1). Total groundcover averaged 80% in KB PQ ST compared to only 45% in the no LM control. These results indicate that a combination of herbicide suppression and ST suppresses LMs adequately to maintain competitive maize grain yields. Additional research under varying climatic conditions will further quantify the risk of LM management systems to increase the sustainable stover harvest of maize biomass feedstocks.

Developing robust relationships between dry matter (DM) and plant number (PN) in interseeded red clover (Trifolium pratenseL.) and winter cereal systems are useful for predicting potential DM. Predicting DM months in advance enhances producers’ ability to determine forage requirements. Data from five winter cereal and red clover studies conducted during the period 2003 to 2009 were synthesized to develop robust relationships between red clover DM and PN using treatments that included different winter cereal species and variety, winter cereal seeding rate, red clover variety, tillage, and soil amendment. Dry matter data were collected during two 40‐d harvests after winter cereal harvest. The relationship between red clover PN and DM was described mathematically by a two‐phase regression for both harvests following winter cereal harvest. During the first harvest, the relationship was described by a parabola in the first line segment while the second line segment had no slope. In the second harvest, the first line segment was a simple positive linear relationship and the second line segment also had no slope. The join point for the first harvest occurred at 90.3 plants m−2while the second harvest join point occurred at 42.3 plants m−2. Red clover PN above 80 plants m−2likely provide around 90% of total maximum DM while red clover PN around 50 plants m−2likely only provides about 70% of total maximum DM.

Soluble organic matter (OM) is a small but very mobile and reactive fraction of soil organic matter (SOM). We characterized the properties of soluble OM from 0‐ to 125‐cm soil depth in maize (Zea maysL.)‐based agricultural systems that were managed with conventional tillage (CT) and no‐tillage (NT) for 23 yr. Water‐extractable organic matter (WEOM) and salt‐extractable organic matter (SEOM) were obtained in a sequential extraction procedure using dilute (0.01M CaCl2) and concentrated (0.5 M K2SO4) salt solutions. Subsequently, WEOM and SEOM were characterized using resin fractionation, specific ultraviolet absorption at 254 nm (SUVA254) and humification indices (HI). Concentrations of C and N of SOM and SEOM and C of WEOM declined with increasing soil depth. In contrast to less pronounced differences in C and N of SEOM in CT and NT soils, those of WEOM were greater (52–116% for C and 26–86% for N) in NT than CT soils throughout the soil profile. The proportion of C and N in SOM recovered as WEOM and SEOM increased with soil depth (three to nine times for C and two to five times for N). The proportion of hydrophilic‐C increased with soil depth, but the proportion of humified OM decreased with soil depth. Consistent with reports that indicate CT enhances OM decomposition, our data suggest WEOM and particularly SEOM fractions in CT soils are more decomposed than NT soils down to 125‐cm depth. The relative pool size and properties of WEOM and SEOM demonstrated a higher in situ contribution of SOM to soluble OM pool with increasing soil depth.

Frost‐seeding red clover (Trifolium pratenseL.) into winter cereals is an efficient establishment method, although performance under contrasting soil management practices remains unclear. Wheat and intercropped red clover productivity were evaluated in intensive tillage (IT), moderate tillage (MT), and no tillage (NT) with and without compost amendment in a corn (Zea maysL.)–soybean [Glycine max(L.) Merr.]–winter wheat (Triticum aestivumL.) and red clover rotation between 2005 and 2010. Wheat yields were not affected by tillage system and averaged 3.80 Mg ha−1but were 10% higher in compost amended soil compared to no compost. Red clover plant density and dry matter (DM) at cereal grain harvest averaged 127 plants m−2and 32 g m−2and were not affected by tillage or amendment treatments. Maximum wheat canopy light interception was attained in late May to early June and ranged from 84 to 91% and typically exceeded 77% light interception for at least 22 d. Red clover root DM increased on average 378% between wheat harvest and 40 d after harvest compared with a 64% average increase in red clover root length. Red clover shoot:root averaged 8.5 at wheat harvest compared with 11.2 40 d after wheat harvest. Producers using this wheat and red clover intercrop should expect no difference in wheat yield or red clover productivity when using IT, MT, or NT.

Constraints to maize (Zea maysL.) stover biomass harvest may be mitigated by using a living mulch (LM) to offset C exports and control soil erosion. Living mulches can compete with the main crop for resources, particularly water. The objectives of this research were to quantify soil water dynamics and maize water use in continuous maize with stover removal. Continuous soil water content (SWC) and reproductive whole‐plant water use were measured in no‐till maize growing in LMs of creeping red fescue (CF) (Festuca rubraL.), Kentucky bluegrass (KB) (Poa pratensisL.), and a no‐LM control between 2008 and 2010 near Ames, IA. In 2 yr with excessive rainfall (2008 and 2010), LMs increased SWC compared to the control at 15 cm. No‐till LM treatments lowered grain yield in 2008 and 2010 compared to the control, although a KB fall strip‐till treatment, which was part of the larger research study, produced yields that were not different than the control all 3 yr. Reproductive water use efficiency for no‐till KB in 2008 and 2009 (51 and 42 g grain per cm water) was 21 and 14% greater than the control (42 and 37) but 24% lower in 2010 (41 vs. 51). Maize water use in the control exhibited a bimodal response averaged across the 3 yr with peak water use occurring at the R1 through R2 period (0.58 cm d−1) and declining to 0.26 cm d−1during R5 through R6. In contrast, no‐till KB exhibited a simple negative linear relationship with water use rates declining from a high of 0.47 cm d−1during the R1 through R2 period to 0.22 cm d−1during R5 through R6. These results indicate LMs may increase SWC and utilize water more effectively, particularly when combining strip‐till and herbicide management.

Molecular-scale dynamic processes involving ions and water at smectite–water interfaces play crucial roles in issues such as contaminant transport, reactivity of geochemical systems, and carbon sequestration, yet little is known about the specific manner in which interfacial ion and water dynamics influence one another, particularly at temperatures below 0 °C. In this work, we discuss the effects of the charge-balancing cation on the structure and dynamics of alkali metals and H2O at the mineral–water interfaces of alkali metal–smectite pastes over a broad range of temperatures. New variable-temperature 2H and 23Na NMR spectroscopic data for a Na–hectorite paste presented here in combination with the results from our previous studies of Cs– and K–hectorite pastes reveal a common anisotropic mechanism of 2H motion for 2H2O restricted by proximity to a surface or cation between −50 and −20 °C. This motion is well modeled by combined fast-limit C2librations about the 2H2O molecular dipole moment and fast-limit octahedral-type jumps of 2H2O molecules about the C3symmetry axis of a slightly compressed metal–H2O complex. At higher temperatures, 2H2O dynamics are dominated by diffusion and/or chemical exchange of deuterons and differ for Na- and K-exchanged samples. Comparing our collective 39K, 133Cs, and 23Na VT NMR results shows that Na+has less affinity for the smectite surface in pastes than K+or Cs+, that the influence of 2H2O and 2H2O content on alkali metal motion decreases from Na+to K+to Cs+, and that slow-to-intermediate (rate < 104–105Hz) two-site exchange is a significant dynamic process above −80 °C only for Cs+.

Interseeding red clover (Trifolium pratenseL.) or alfalfa (Medicago sativaL.) into winter cereals in the North Central United States can provide forage and a green manure crop. We hypothesized that winter cereal canopy traits such as leaf area index (LAI) and whole plant dry matter (DM) would influence interseeded legume establishment and productivity, yet the effect of canopy traits on resource competition in intercropping systems is not well understood. This study was conducted from 2005 to 2007 to evaluate the impact of diverse cereal canopy traits on the establishment of frost‐seeded legume intercrops. In March, red clover and alfalfa were frost‐seeded into three winter wheat (Triticum aestivumL.) and three triticale (X TriticosecaleWittmack) varieties selected for differences in maximum LAI, plant height, and DM. Across three growing seasons, the cereals produced a range of LAI from 2.1 to 6.2 and whole plant harvest DM of 817 to 2029 g m−2. In the 2 yr with legume data, densities were influenced by cereal 1 yr and DM was affected by cereal both years. Alfalfa and red clover densities were similar, yet DM production was 42% higher in red clover 40 d after grain harvest. The presence of a legume intercrop did not affect grain yield, but reduced weed densities and weed DM 40 d after harvest. Producers implementing this intercrop may select cereal varieties based on grain yield, but must be cautious of varieties known to produce above normal LAI values because of the potential to reduce legume productivity.