Time and distance to clear wood in pruned red alder saplings

This paper was published in: Deal, R.L. and C.A. Harrington, eds. 2006. Red alder—a state of knowledge. General Technical Report PNW-GTR-669. Portland, OR: U.S. Department of Agriculture, Pacific Northwest Research Station. 150 p.Pruning trials in young alder stands were sampled to evaluate response to pruning. Effects of pruning (1) live branches on different dates, and (2) dead branches with or without damaging the branch collar were assessed on trees pruned in 3- and 6-year-old plantations, respectively. Six years after pruning, stem sections were collected and dissected in the longitudinal-radial plane to expose the center of the stem and branch stub. Ring counts and linear measurements were made for various boundaries or points, including time of pruning, stub length, defect, and beginning of clear wood formation. Pruning during the growing season and, to a lesser extent, late in the growing season when leaf abscission was beginning, resulted in shorter times and distances to formation of clear wood (2.1 years, 14.5 mm) than pruning in the dormant season or just prior to the beginning of the growing season (2.6 years, 18.6 mm). Cutting the branch collar on dead branches led to shorter times and distances to clear wood (2.8 years, 21.9 mm) than intentionally avoiding such wounding (3.5 years, 24.8 mm); these differences were associated with shorter branch stubs as there were no differences in the amount of defect. Epicormic branching was minimal in the two pruning studies, averaging less than one branch per tree in the date of pruning test and only two branches per tree in the branch collar wounding study. Assessments for comparable unpruned trees indicated that times to form clear wood after branch death would be markedly greater and that epicormic branching was equal to or greater than that determined for pruned trees. Although statistically significant differences occurred among different pruning dates and with branch collar wounding, the decision to prune or not prune is of much greater practical importance, regardless of when (date) or how it is done. Such pruning decisions can be made by using this information on time and distance to clear wood in economic analyses developed with available data on tree growth, log volume, lumber recovery, pruning costs, and price differentials for clear vs. knotty wood.Keywords: biology and ecology, inventory, economics, Alnus rubra, history, mixed-species stands, silviculture, pruning, plantation establishment, supplyKeywords: biology and ecology, inventory, economics, Alnus rubra, history, mixed-species stands, silviculture, pruning, plantation establishment, suppl

The histone binding capacity of SPT2 controls chromatin structure and function in Metazoa

Histone chaperones control nucleosome density and chromatin structure. In yeast, the H3-H4 chaperone Spt2 controls histone deposition at active genes but its roles in metazoan chromatin structure and organismal physiology are not known. Here we identify the Caenorhabditis elegans ortholog of SPT2 (CeSPT-2) and show that its ability to bind histones H3-H4 is important for germline development and transgenerational epigenetic gene silencing, and that spt-2 null mutants display signatures of a global stress response. Genome-wide profiling showed that CeSPT-2 binds to a range of highly expressed genes, and we find that spt-2 mutants have increased chromatin accessibility at a subset of these loci. We also show that SPT2 influences chromatin structure and controls the levels of soluble and chromatin-bound H3.3 in human cells. Our work reveals roles for SPT2 in controlling chromatin structure and function in Metazoa.</p

Standards of care for CFTR variant-specific therapy (including modulators) for people with cystic fibrosis

Cystic fibrosis (CF) has entered the era of variant-specific therapy, tailored to the genetic variants in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. CFTR modulators, the first variant-specific therapy available, have transformed the management of CF.The latest standards of care from the European CF Society (2018) did not include guidance on variant-specific therapy, as CFTR modulators were becoming established as a novel therapy. We have produced interim standards to guide healthcare professionals in the provision of variant-specific therapy for people with CF.Here we provide evidence-based guidance covering the spectrum of care, established using evidence from systematic reviews and expert opinion. Statements were reviewed by key stakeholders using Delphi methodology, with agreement (≥80%) achieved for all statements after one round of consultation. Issues around accessibility are discussed and there is clear consensus that all eligible people with CF should have access to variant-specific therapy

Wood Density and Fiber Length in Young Populus Stems: Relation to Clone, Age, Growth Rate, and Pruning

Cross-sectional disks were cut at two stem heights (1.5 m and 3.0 m) from 9-year-old trees of three Populus clones grown in an intensively-cultured plantation in western Washington. At age 1.5 years, when the trees averaged 3.4 m tall, half of the trees were pruned by removing all branches below 1.8 m. Ring width, wood density, and fiber length were measured for each ring. Pruning had no effect on mean ring width or wood properties, averaged over the entire disk or on rings produced during the 2nd through the 4th years. Averaged over all trees, wood density of the 1.5-m sample was 0.37 g cm-3 during the first 3 years, decreased somewhat at age 4 or 5, and then increased to an average of 0.45 g cm-3 at age 9. Fiber length increased from 0.57 mm at age 1 to nearly 1.0 mm at age 9. Averaged over all disks at 1.5 m, clones differed significantly in ring width, wood density, and fiber length. Mean values for the two wood properties at 3.0 m were slightly lower than those at 1.5 m and did not differ significantly among clones. Within clone correlations between ring width and wood density or fiber length or between wood properties were low, and generally nonsignificant or inconsistent

Wood density and fiber length in young populus stems: relation to clone, age, growth rate, and pruning

Cross-sectional disks were cut at two stem heights (1.5 m and 3.0 m) from 9-year-old trees of three Populus clones grown in an intensively-cultured plantation in western Washington. At age 1.5 years, when the trees averaged 3.4 m tall, half of the trees were pruned by removing all branches below 1.8 m. Ring width, wood density, and fiber length were measured for each ring. Pruning had no effect on mean ring width or wood properties, averaged over the entire disk or on rings produced during the 2nd through the 4th years. Averaged over all trees, wood density of the 1.5 m sample was 0.37 g cm-3 during the first 3 years, decreased somewhat at age 4 or 5, and then increased to an average of 0.45 g cm-3 at age 9. Fiber length increased from 0.57 mm at age 1 to nearly 1.0 mm at age 9. Averaged over all disks at 1.5 m, clones differed significantly in ring width, wood density, and fiber length. Mean values for the two wood properties at 3.0 m were slightly lower than those at 1.5 m and did not differ significantly among clones. Within clone correlations between ring width and wood density or fiber length or between wood properties were low, and generally non significant or inconsistent.Keywords: clones, fiber length, pruning, ring width, wood density, populus, sampling heigh

Skynet Junior Scholars: Bringing Astronomy to Deaf and Hard of Hearing Youth

Skynet Junior Scholars (SJS), funded by the National Science Foundation, aims to engage middle school youth from diverse audiences in investigating the universe with research quality robotic telescopes. SJS project development goals include: 1) Online access to optical and radio telescopes, data analysis tools, and professional astronomers, 2) An age-appropriate web-based interface for controlling remote telescopes, 3) Inquiry-based standards-aligned instructional modules. From an accessibility perspective, the goal of the Skynet Junior Scholars project is to facilitate independent access to the project by all youth including those with blindness or low vision and those who are Deaf or Hard of Hearing.Deaf and Hard of Hearing (DHH) students have long been an underserved population within STEM fields, including astronomy. Two main barriers include: (1) insufficient corpus of American Sign Language (ASL) for astronomy terminology, and (2) DHH education professionals who lack astronomy background. A suite of vocabulary, accessible hands-on activities, and interaction with trained professionals, are critical for enhancing the background experiences of DHH youth, as they may come to an astronomy lesson lacking the basic "incidental learning" that is often taken for granted with hearing peers (for example, from astronomy in the media).A collaboration between the Skynet Junior Scholars (SJS) project and the Wisconsin School for the Deaf is bringing astronomy to the DHH community in an accessible way for the first time. We follow a group of seven DHH youth over one semester as they interact with the SJS tools and curriculum to understand how they assimilate astronomy experiences and benefit from access to telescopes both directly (on school campus and at Yerkes Observatory) and through Skynet's robotic telescope network (optical and radio telescopes, inquiry-based modules, data analysis tools, and professional astronomers). We report on our first findings of resources and best practices for engaging DHH youth in astronomy in the future

The histone chaperone SPT2 regulates chromatin structure and function in Metazoa.

Acknowledgements: We are grateful to members of the Labib laboratory for invaluable advice on recombinant protein purification and C. elegans techniques, and to members of the Rouse laboratory for fruitful discussion. We thank K. Rasmussen for help with ATAC–seq in human cells; R. Sundaramoorthy and T. Owen-Hughes (University of Dundee) for the gift of recombinant Xenopus histones; B. Meier and F. Pelisch for help with C. elegans genetics; K. Labib for helpful comments on the manuscript and for the gift of the His6–Ulp1 plasmid; V. Alvarez for help with microscopy and A. Knebel for advice on protein purification. We thank the technical support of the MRC PPU including the DNA Sequencing Service, Tissue Culture team, Reagents and Services team, and the Flow Cytometry & Cell Sorting Facility at the University of Dundee; we thank the (EPI)2 Imaging platform - UMR7216 Epigenetics and Cell Fate centre (Paris) for access to instruments; we also thank N. Wood for help with cloning, and F. Brown and J. Hastie for SPT2 antibody production and purification. We acknowledge the excellent support teams and admin staff in MRC PPU and the School of Life Sciences (University of Dundee) where most of this work was done. This work was supported by the Medical Research Council (grant number MC_UU_00018/5) and the pharmaceutical companies supporting the Division of Signal Transduction Therapy Unit (Boehinger‐Ingelheim, GlaxoSmithKline and Merck KGaA) (J.R.); the Wellcome Trust (grant number 217170) and the MRC (grant number MR/S021620/1) (J.A.); the Korean Institute for Basic Science (grant number IBS-R022-A2-2023) (A.G. and S.G.M.R.); Cancer Research UK (grant number C13474/A27826) and the Wellcome Trust (grant number 219475/Z/19/Z) (E.A.M.); the European Research Council (grant number ERC-2018-CoG-818625) (S.E.P.); the Medical Research Council (grant number MC_UU_00007/15) (C.P.P.); the European Research Council (ERC-2016-StG-715127) (C.A.); the Medical Research Council (grant number MC_U105192715 to L. Passmore). G.S. was supported by an EMBO Long-Term Fellowship (ALTF 951-2018) and a SULSA ECR Development Fund; this project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 845448 (G.S.). G.F. was supported by an EMBO Long-Term Fellowship (ALTF 1132-2018). P.A. was supported by an EMBO Long-Term Fellowship (ALTF 692–2018). For the purpose of open access, the MRC Protein Phosphorylation and Ubiquitylation Unit has applied a CC BY public copyright license to any Author Accepted Manuscript version arising. The funders had no direct role in study design, data collection and analysis, decision to publish or preparation of the manuscript.Histone chaperones control nucleosome density and chromatin structure. In yeast, the H3-H4 chaperone Spt2 controls histone deposition at active genes but its roles in metazoan chromatin structure and organismal physiology are not known. Here we identify the Caenorhabditis elegans ortholog of SPT2 (CeSPT-2) and show that its ability to bind histones H3-H4 is important for germline development and transgenerational epigenetic gene silencing, and that spt-2 null mutants display signatures of a global stress response. Genome-wide profiling showed that CeSPT-2 binds to a range of highly expressed genes, and we find that spt-2 mutants have increased chromatin accessibility at a subset of these loci. We also show that SPT2 influences chromatin structure and controls the levels of soluble and chromatin-bound H3.3 in human cells. Our work reveals roles for SPT2 in controlling chromatin structure and function in Metazoa

Standards of care for CFTR variant-specific therapy (including modulators) for people with cystic fibrosis

Cystic fibrosis (CF) has entered the era of variant-specific therapy, tailored to the genetic variants in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. CFTR modulators, the first variant-specific therapy available, have transformed the management of CF. The latest standards of care from the European CF Society (2018) did not include guidance on variant-specific therapy, as CFTR modulators were becoming established as a novel therapy. We have produced interim standards to guide healthcare professionals in the provision of variant-specific therapy for people with CF. Here we provide evidence-based guidance covering the spectrum of care, established using evidence from systematic reviews and expert opinion. Statements were reviewed by key stakeholders using Delphi methodology, with agreement (≥80%) achieved for all statements after one round of consultation. Issues around accessibility are discussed and there is clear consensus that all eligible people with CF should have access to variant-specific therapy