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Glucose has been shown to shorten lifespan in Caenorhabditis elegans. The connection of glucose to stress resistance in C. elegans, however, appears to be complex. We have shown glucose to be protective against heat stress early in adulthood (1-day-old adults), in both wild-type (WT, N2 strain) animals and those with a mutation in the gene encoding the C. elegans insulin receptor, daf-2. The protection conferred by 1 day on high glucose continues in mid-life (7-day-old adults) for daf-2, but not for WT. Mid-life and late-life stress following 7 or 13 days on high glucose shows glucose enrichment to be neutral or detrimental for recovery from heat stress in both strains. These results were also observed for animals exposed to sorbitol instead of glucose, suggesting the osmotic stress conferred by high concentrations of carbohydrate to be the basis of the resistance to heat stress.

This paper reports a temperature-dependent ASM-HEMT for modeling GaN HEMTs at elevated temperatures. Modifications to the standard ASM-HEMT were developed to accurately capture the DC and RF measurements collected at varying chuck temperatures. Several results are reported which validate the model including DC-IV, pulsed-IV, scattering-parameter, and load-pull measurements. The model is then used to extrapolate the performance of the GaN HEMT to twice the operating temperature at which the model was validated. This work could be useful for understanding and modeling GaN HEMTs in high-temperature environment applications.

Beech leaf disease (BLD) is an emerging forest infestation affecting beech trees (Fagus spp.) in the midwestern and northeastern United States and southeastern Canada. BLD is attributed to the newly recognized nematode Litylenchus crenatae subsp. mccannii. First described in Lake County, Ohio, BLD leads to the disfigurement of leaves, canopy loss, and eventual tree mortality. Canopy loss limits photosynthetic capacity, likely impacting tree allocation to belowground carbon storage. Ectomycorrhizal fungi are root symbionts, which rely on the photosynthesis of autotrophs for nutrition and growth. Because BLD limits tree photosynthetic capacity, ECM fungi may receive less carbohydrates when associating with severely affected trees compared with trees without BLD symptoms. We sampled root fragments from cultivated F. grandifolia sourced from two provenances (Michigan and Maine) at two timepoints (fall 2020 and spring 2021) to test whether BLD symptom severity alters colonization by ectomycorrhizal fungi and fungal community composition. The studied trees are part of a long-term beech bark disease resistance plantation at the Holden Arboretum. We sampled from replicates across three levels of BLD symptom severity and compared fungal colonization via visual scoring of ectomycorrhizal root tip abundance. Effects of BLD on fungal communities were determined through high-throughput sequencing. We found that ectomycorrhizal root tip abundance was significantly reduced on the roots of individuals of the poor canopy condition resulting from BLD, but only in the fall 2020 collection. We found significantly more ectomycorrhizal root tips from root fragments collected in fall 2020 than in spring 2021, suggesting a seasonal effect. Community composition of ectomycorrhizal fungi was not impacted by tree condition but did vary between provenances. We found significant species level responses of ectomycorrhizal fungi between levels of both provenance and tree condition. Of the taxa analyzed, two zOTUs had significantly lower abundance in high-symptomatology trees compared with low-symptomatology trees. These results provide the first indication of a belowground effect of BLD on ectomycorrhizal fungi and contribute further evidence to the role of these root symbionts in studies of tree disease and forest pathology.

Editorial

Abstract The Mid-Atlantic Microbiome Meet-up (M3) organization brings together academic, government, and industry groups to share ideas and develop best practices for microbiome research. In January of 2018, M3 held its fourth meeting, which focused on recent advances in biodefense, specifically those relating to infectious disease, and the use of metagenomic methods for pathogen detection. Presentations highlighted the utility of next-generation sequencing technologies for identifying and tracking microbial community members across space and time. However, they also stressed the current limitations of genomic approaches for biodefense, including insufficient sensitivity to detect low-abundance pathogens and the inability to quantify viable organisms. Participants discussed ways in which the community can improve software usability and shared new computational tools for metagenomic processing, assembly, annotation, and visualization. Looking to the future, they identified the need for better bioinformatics toolkits for longitudinal analyses, improved sample processing approaches for characterizing viruses and fungi, and more consistent maintenance of database resources. Finally, they addressed the necessity of improving data standards to incentivize data sharing. Here, we summarize the presentations and discussions from the meeting, identifying the areas where microbiome analyses have improved our ability to detect and manage biological threats and infectious disease, as well as gaps of knowledge in the field that require future funding and focus.

The purpose of this paper is to present the experiences of Indigenous youth when a critical literacies/Indigenous knowledges (IK) approach was used in a graphic novel creation project. We conducted research over a six-week period in two alternative high schools in British Columbia. In this paper, we look primarily at research findings from the Indigenous program. We analyzed classroom observations, the graphic novels, and transcripts of semi-structured interviews according to four principles of critical literacy: understanding power, control, and equity of information; collaboration using multiple perspectives; authentic and multimodal learning; and enacting social change and civic engagement.

Recently, single-crystal Cu-Al-Mn (CAM) superelastic alloy (SEA) bars have been developed to address the shortcomings of traditional Ni-Ti SEA bars, i.e., high cost, low workability, and lack of superelasticity at low temperatures. The CAM SEAs have a wide range of potential applications in biomedical, aerospace, mechanical, and civil industries. However, no quantitative information is available on the chemical stability of this relatively new metal alloy. This study quantified the chemical resistance of CAM SEA bars compared with that of mild steel bars in terms of mass loss and changes in mechanical and physical properties. Tensile testing was performed to estimate the reduction in the yield load of the samples after chemical aging. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were carried out to determine the oxidation potential of the material. Corrosion parameters of CAM SEAs were quantified through potentiodynamic polarization tests. The erosion rate of CAM SEAs was also estimated using these corrosion parameters to compare against the typical values reported for mild steel. The CAM SEAs had a chemical resistivity significantly superior to that of mild steel regardless of the environmental exposure conditions tested in this paper. It was also found that CAM SEAs have comparable corrosion resistance to another Cu-based shape memory alloy composition: Cu-Al-Ni. [ABSTRACT FROM AUTHOR]

Purpose:The pre-illness basal mean arterial BP (MAP) is an important reference point to gauge the degree of relative hypotension among unwell patients. We aimed to assess mean bias, correlation, and agreement between basal MAPmeasuredduring nighttime ambulatory BP monitoring (ABPM) and basal MAPestimatedusing a standardized protocol. Materials and methods:For a cohort of 137 consecutive patients, aged ≥40 years, who recently underwent ABPM, a blinded investigator estimated basal MAP from up to five most recent clinic BP measurements. Both basal MAP values, measured and estimated, were compared pairwise for each participant. Results:We traced a median of 4 [interquartile range 3–5] previous BP measurements per patient over a median period of 132 [interquartile range 55–277] days up until the ABPM test. The estimated basal MAP (mean 88 ± 8 mmHg) was linearly related (Pearson’sr = 0.41,p = 0.0001) to the measured basal MAP (mean 88 ± 12 mmHg). Bland-Altman plot revealed a mean bias of 0.3 mmHg with agreement limits of ±22 mmHg. Conclusions:The mean bias between estimated and measured values for basal MAP was insignificant and modest. When a recent nighttime ABPM is unavailable, a protocol based on recent clinic BP readings can be used to estimate patient’s basal MAP. Study registration:Australian New Zealand Clinical Trials Registry ACTRN12613001382763. [ABSTRACT FROM PUBLISHER]

Purpose: The pre-illness basal mean arterial BP (MAP) is an important reference point to gauge the degree of relative hypotension among unwell patients. We aimed to assess mean bias, correlation, and agreement between basal MAP measured during nighttime ambulatory BP monitoring (ABPM) and basal MAP estimated using a standardized protocol. Materials and methods: For a cohort of 137 consecutive patients, aged ≥40 years, who recently underwent ABPM, a blinded investigator estimated basal MAP from up to five most recent clinic BP measurements. Both basal MAP values, measured and estimated, were compared pairwise for each participant. Results: We traced a median of 4 [interquartile range 3–5] previous BP measurements per patient over a median period of 132 [interquartile range 55–277] days up until the ABPM test. The estimated basal MAP (mean 88 ± 8 mmHg) was linearly related (Pearson’s r = 0.41, p = 0.0001) to the measured basal MAP (mean 88 ± 12 mmHg). Bland-Altman plot revealed a mean bias of 0.3 mmHg with agreement limits of ±22 mmHg. Conclusions: The mean bias between estimated and measured values for basal MAP was insignificant and modest. When a recent nighttime ABPM is unavailable, a protocol based on recent clinic BP readings can be used to estimate patient’s basal MAP. Study registration: Australian New Zealand Clinical Trials Registry ACTRN12613001382763.