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Roadside vegetation provides a multitude of ecosystem services, including pollutant remediation, runoff reduction, wildlife habitat, and aesthetic scenery. Establishment of permanent vegetation along paved roads after construction can be challenging, particularly within 1 m of the pavement. Adverse soil conditions could be one of the leading factors limiting roadside vegetation growth. In this study, we assessed soil physical and chemical properties along a transect perpendicular to the road at six microtopographic positions (road edge, shoulder, side slope, ditch, backslope, and field edge) along two highway segments near Beaver Crossing and Sargent, NE. At the Beaver Crossing site, Na concentration was 81 times, exchangeable Na 66 times, and cone index (compaction parameter) six times higher at the road‐edge position (closest to the paved road and with sparse vegetation) compared to positions with abundant vegetation (ditch or field edge). At the Sargent site, Na concentration was 111 times, exchangeable Na 213 times, and cone index up to two times higher at the road‐edge position compared with ditch or field‐edge positions. Likewise, electrical conductivity was higher and macroaggregation and water infiltration were lower at the road edge than at the ditch or field‐edge positions. Soil properties improved with increasing distance from the road. Exchangeable Na percentage and cone index at the road‐edge position exceeded threshold levels for the growth of sensitive plants. Thus, high Na concentration and increased compaction at the road edge appear to be the leading soil properties limiting vegetation establishment along Nebraska highways.

In this review, Ruis and Boulton provide an updated t-loop model of chromosome end protection, suggesting that the data is supportive of a critical role for t-loops in protecting chromosome ends from NHEJ and ATM activation, but that other mechanisms are involved.

Cover crop (CC) impacts on soil ecosystem services including erosion control, C sequestration, soil productivity, and others have been reviewed. However, CC impacts on soil physical properties, which affect the soil's ability to perform a variety of soil ecosystem services, have not been synthesized. We reviewed 98 peer‐reviewed publications up to 10 June 2020 on CCs and soil physical properties. Our review indicates that, in most studies, CCs reduce soil penetration resistance or compaction by 0–29% (average, 5%). They improve wet aggregate stability by 0–95% (average, 16%) and cumulative infiltration by 0–190% (average, 43%) but have negligible impacts on bulk density, dry aggregate stability, saturated hydraulic conductivity (Ksat), unsaturated hydraulic conductivity (Kunsat), volumetric water content at −10 to −33 kPa matric potential (field capacity), and plant available water. Soils under CCs can be cooler in daytime and warmer at nighttime, and warmer in winter and cooler in the rest of year. Volumetric heat capacity increases and thermal diffusivity decreases, indicating that CCs could moderate heat transport rate. Soil texture, tillage system, CC‐derived soil C concentration, and CC duration affect CC impacts on physical properties. For example, the positive impacts from CCs can increase as CC management duration increases and combining CCs with no‐till can improve water infiltration more than with tilled soils. Long‐term data on hydraulic properties, thermal properties, dry aggregate stability, and pore‐size distribution are scant. In general, CCs improve most soil physical properties, but the magnitude of improvement is highly site‐ and management specific.

Isopropylated and tert-butylated triarylphosphate esters (ITPs and TBPPs, respectively) are plasticizers and flame retardants that are ubiquitous in indoor environments; however, no studies to date have characterized their metabolism. Using human liver subcellular S9 fractions, phase I and II in vitrometabolism of triphenyl phosphate (TPHP), 4-tert-butylphenyl diphenyl phosphate (4tBPDPP), 2-isopropylphenyl diphenyl phosphate (2IPPDPP), and 4-isopropylphenyl diphenyl phosphate (4IPPDPP) was investigated at 1 and 10 μM doses. Parent depletion and the formation of known or suspected metabolites (e.g., likely hydrolysis or hydroxylated products), including diphenyl phosphate (DPHP), hydroxyl-triphenyl phosphate (OH-TPHP), isopropylphenyl phenyl phosphate (ip-PPP), and tert-butylphenyl phenyl phosphate (tb-PPP), were monitored and quantified via GC/MS or LC-MS/MS. tb-PPP and its conjugates were identified as the major in vitrometabolites of 4tBPDPP and accounted for 71% and 49%, respectively, of the parent molecule that was metabolized during the incubation. While the mass balance between parents and metabolites was conserved for TPHP and 4tBPDPP, approximately 20% of the initial parent mass was unaccounted for after quantifying suspected metabolites of 2IPPDPP and 4IPPDPP that had authentic standards available. Two novel ITP metabolites, mono-isopropenylphenyl diphenyl phosphate and hydroxy-isopropylphenyl diphenyl phosphate, were tentatively identified by high-resolution mass spectrometry and screened for in recently collected human urine where mono-isopropenylphenyl diphenyl phosphate was detected in one of nine samples analyzed. This study provides insight into the biological fate of ITP and TBPP isomers in human tissues and is useful in identifying appropriate biomarkers of exposure to monitor, particularly in support of epidemiological studies.

The primary goal of bioprocess cell line development is to obtain high product yields from robustly growing and well-defined clonal cell lines in timelines measured in weeks rather than months. Likewise, high-throughput screening of B cells and hybridomas is required for most cell line engineering workflows. A substantial bottleneck in these processes is detecting and isolating rare clonal cells with the required characteristics. Traditionally, this was achieved by the resource-intensive method of limiting dilution cloning, and more recently aided by semiautomated technologies such as cell sorting (e.g., fluorescence-activated cell sorting) and colony picking. In this paper we report on our novel Cyto-Mine Single Cell Analysis and Monoclonality Assurance System, which overcomes the limitations of current technologies by screening hundreds of thousands of individual cells for secreted target proteins, and then isolating and dispensing the highest producers into microtiter plate wells (MTP). The Cyto-Mine system performs this workflow using a fully integrated, microfluidic Cyto-Cartridge. Critically, all reagents and Cyto-Cartridges used are animal component-free (ACF) and sterile, thus allowing fast, robust, and safe isolation of desired cells.

The protection of telomere ends by the shelterin complex prevents DNA damage signalling and promiscuous repair at chromosome ends. Evidence suggests that the 3′ single-stranded telomere end can assemble into a lasso-like t-loop configuration1,2, which has been proposed to safeguard chromosome ends from being recognized as DNA double-strand breaks2. Mechanisms must also exist to transiently disassemble t-loops to allow accurate telomere replication and to permit telomerase access to the 3′ end to solve the end-replication problem. However, the regulation and physiological importance of t-loops in the protection of telomere ends remains unknown. Here we identify a CDK phosphorylation site in the shelterin subunit at Ser365 of TRF2, whose dephosphorylation in S phase by the PP6R3 phosphatase provides a narrow window during which the RTEL1 helicase can transiently access and unwind t-loops to facilitate telomere replication. Re-phosphorylation of TRF2 at Ser365 outside of S phase is required to release RTEL1 from telomeres, which not only protects t-loops from promiscuous unwinding and inappropriate activation of ATM, but also counteracts replication conflicts at DNA secondary structures that arise within telomeres and across the genome. Hence, a phospho-switch in TRF2 coordinates the assembly and disassembly of t-loops during the cell cycle, which protects telomeres from replication stress and an unscheduled DNA damage response.

During pregnancy, the supply of thyroid hormone (TH) to the fetus is critically important for fetal growth, neural development, metabolism, and maintenance of pregnancy. Additionally, in cases where maternal and placental TH regulation is significantly altered, there is an increased risk of several adverse pregnancy outcomes. It is unclear what may be disrupting placental TH regulation; however, studies suggest that environmental contaminants, such as polybrominated diphenyl ethers (PBDEs), could be playing a role. In this study, Wistar rats were gestationally exposed to a mixture of PBDEs for 10 days. THs and PBDEs were quantified in paired maternal serum, dissected placenta, and fetuses, and mRNA expression of transporters in the placenta was assessed. Significantly higher concentrations of PBDEs were observed in the fetal portion of the placenta compared with the maternal side, suggesting that PBDEs are actively transported across the interface. PBDEs were also quantified in 10 recently collected human maternal and fetal placental tissues; trends paralleled observations in the rat model. We also observed an effect of PBDEs on T3 levels in dam serum, as well as suggestive changes in the T3 levels of the placenta and fetus that varied by fetal sex. mRNA expression in the placenta also significantly varied by fetal sex and dose. These observations suggest the placenta is a significant modifier of fetal exposures, and that PBDEs are impacting TH regulation in a sex-specific manner during this critical window of development.

Core IdeasCorn residue baling reduced SOC stocks by 2.16 Mg ha–1yr–1compared with no removal after 3 yr.Baling increased erosion potential and reduced soil microbial biomass.Cattle grazing of corn residues did not generally affect soil properties.Baling and grazing effects on soil properties did not vary with irrigation and tillage system.Baling affected soil properties more than grazing regardless of irrigation and tillage. Baling and grazing of corn (Zea maysL.) residues are common practices in irrigated systems to meet the increasing demand for forage. Our understanding of how such practices affect soil properties under different tillage and irrigation levels is, however, still limited. This study assessed the impacts of corn residue baling and grazing on soil organic C (SOC) stocks, particulate organic matter (POM) concentration, soil microbial communities, sorptivity, and wind and water erosion potential under continuous corn managed with two irrigation (full and limited) and two tillage (no‐till and strip till) levels after 3 yr on a silt loam in the central Great Plains. On average, residue removal was 66% for baling and 24% for grazing. Baling reduced SOC stocks by 2.16 Mg ha–1yr–1for the 0‐ to 20‐cm depth compared with no residue removal, but residue grazing, irrigation, and tillage had no effects. Full irrigation decreased mean weight diameter (MWD) of wet aggregates by 19% compared with limited irrigation, attributed to Na accumulation. No‐till had lower wind‐erodible fraction and greater microbial biomass than strip till. Regardless of irrigation and tillage, baling increased wind‐erodible fraction by 43% and decreased MWD by 56%, POM concentration by 41%, sorptivity by 57%, and microbial biomass in the upper 5‐cm depth compared with grazing and no residue removal. Grazing increased POM concentration and actinomycete biomass compared with no residue removal. Overall, changes in soil properties due to baling were larger and more rapid than in most previous studies, while grazing had fewer effects on soil properties.