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The evolutionary processes that drive universal therapeutic resistance in adult patients with diffuse glioma remain unclear1,2. Here we analysed temporally separated DNA-sequencing data and matched clinical annotation from 222 adult patients with glioma. By analysing mutations and copy numbers across the three major subtypes of diffuse glioma, we found that driver genes detected at the initial stage of disease were retained at recurrence, whereas there was little evidence of recurrence-specific gene alterations. Treatment with alkylating agents resulted in a hypermutator phenotype at different rates across the glioma subtypes, and hypermutation was not associated with differences in overall survival. Acquired aneuploidy was frequently detected in recurrent gliomas and was characterized by IDH mutation but without co-deletion of chromosome arms 1p/19q, and further converged with acquired alterations in the cell cycle and poor outcomes. The clonal architecture of each tumour remained similar over time, but the presence of subclonal selection was associated with decreased survival. Finally, there were no differences in the levels of immunoediting between initial and recurrent gliomas. Collectively, our results suggest that the strongest selective pressures occur during early glioma development and that current therapies shape this evolution in a largely stochastic manner.

Learning to count and to produce the correct sequence of number words in English is not a simple process. In NSW government schools taking part in Early Action for Success, over 800 students in each of the first 3 years of school were assessed every 5 weeks over the school year to determine the highest correct oral count they could produce. Rather than displaying a steady increase in the accurate sequence of the number words produced, the kindergarten data reported here identified clear, substantial hurdles in the acquisition of the counting sequence. The large-scale, longitudinal data also provided evidence of learning to count through the teens being facilitated by the semi-regular structure of the number words in English. Instead of occurring as hurdles to starting the next counting sequence, number words corresponding to some multiples of ten (10, 20 and 100) acted as if they were rest points. These rest points appear to be artefacts of how the counting sequence is acquired.

Low-cost methods to measure forest structure are needed to consistently and repeatedly inventory forest conditions over large areas. In this study we investigate low-cost pushbroom Digital Aerial Photography (DAP) to aid in the estimation of forest volume over large areas in Washington State (USA). We also examine the effects of plot location precision (low versus high) and Digital Terrain Model (DTM) resolution (1 m versus 10 m) on estimation performance. Estimation with DAP and post-stratification with high-precision plot locations and a 1 m DTM was 4 times as efficient (precision per number of plots) as estimation without remote sensing and 3 times as efficient when using low-precision plot locations and a 10 m DTM. These findings can contribute significantly to efforts to consistently estimate and map forest yield across entire states (or equivalent) or even nations. The broad-scale, high-resolution, and high-precision information provided by pushbroom DAP facilitates used by a wide variety of user types such a towns and cities, small private timber owners, fire prevention groups, Non-Governmental Organizations (NGOs), counties, and state and federal organizations.

Scholarly communication faces increasing economical and ethical challenges, including pricing policies and overbearing behavior of commercial publishing houses. Based on the hypothesis that a diamond open access neuropathology journal of a high scientific and technical quality can be run entirely by neuropathologists, we launched Free Neuropathology (FNP; freeneuropathology.org) in January 2020. Classical publisher activities, such as copyediting, layout, website maintenance, and journal promotion, are undertaken by neuropathologists and neuroscientists using free open access software. The journal is free for both readers and authors, and papers are published under a Creative Commons BY SA licence, where copyright remains with the authors. Based on 26 articles published by August 2020, it takes FNP 11.1 days from submission to first, and 19.9 days to final, decision. High-quality copyediting, layout, and online publishing in the final format is accomplished in only 8 days. Absence of a commercial publisher enables prioritization of democratic and scientifically-driven decisions on editorial structure, website design, journal promotion, paper formatting, special article series, and number of accepted papers. This new model of journal publishing, which returns the control of scholarly communication to scientists, will be of interest to neuropathologists and wider scientific community alike.Learning ObjectivesSummarize the current state and driving forces behind commercial and non-commercial scientific publishing in neuropathology.Describe the advantages and challenges of a non-commercial publishing platform for neuropathology.

QinetiQ has a major and long standing interest in the dynamic deformation and fracture response of materials and has been very active in developing constitutive and fracture models. These models have been validated across a number of different tests, triaxial stress states and strain rates [1] . The models have also been used on a range of Defence and commercial applications where the material characterisation has been controlled by QinetiQ. However, they have not been exercised extensively on industrial applications using available data in the literature. The constitutive models are based on interrupted tensile testing to separate the strain hardening, strain rate and thermal softening and for body centred cubic (BCC) steels give rise to the modified Armstrong-Zerilli model [1] . The ductile fracture model is based on a path dependent approach linking the damage to the stress-state resulting in the Goldthorpe Path Dependent Fracture (PDF) model [2] . Essentially the Goldthorpe PDF model gives a single value of critical damage (Void Fracture Number – VFN) applicable to all stress states and strain rates. This paper describes the application of the QinetiQ constitutive and fracture models in the simulation of an industrial application and assesses their ability to capture the main deformation and fracture mechanisms. The application was an anchor dropping onto a pipe both dynamically and statically to determine whether the pipe is fractured [3] . The DYNA3D hydrocode was used to simulate the dynamic impact and the subsequent deformation and fracture of the pipe. The material constants for the model were estimated for the actual materials by using the testing published in the literature [3] and comparing them with ‘similar’ materials within the QinetiQ materials database. Given there is some subjectivity in this process, the likeliness of failure was investigated, particularly regarding the VFN relating to the fracture process. The results are discussed with respect to the degree of deformation and fracture within the pipe and the sensitivity of these features to the input conditions. The results are also discussed in the context of whether the predictive accuracy of the simulations is such that they could ultimately be used to design a pipe that is more resistant to the impact loading, for example by increasing the yield strength through processing.

A series of plate impact experiments were conducted to investigate the shock response of a simulant for adobe, a traditional form of building material widely used around the world. Air dried bricks were sourced from the London brick company, dry machined and impacted at a range of velocities in a single stage gas gun. The shock Hugoniot was determined (Us =2.26up+0.37) as well as release information. The material was found to behave in a manner which was similar to that of loose sand and considerably less stiff than a weak porous sandstone. The effect of any cementing of the grains was examined by shocking powdered samples contained within a cell arrangement.

Objective To study the presence of 9p deletion and p16, cyclin D1 and Myc expression and their respective diagnostic and prognostic interest in oligodendrogliomas. Methods We analyzed a retrospective series of 40 consecutive anaplastic oligodendrogliomas (OIII) from a single institution and compared them to a control series of 10 low grade oligodendrogliomas (OII). Automated FISH analysis of chromosome 9p status and immunohistochemistry for p16, cyclin D1 and Myc was performed for all cases and correlated with clinical and histological data, event free survival (EFS) and overall survival (OS). Results Chromosome 9p deletion was observed in 55% of OIII (22/40) but not in OII. Deletion was highly correlated to EFS (median = 29 versus 53 months, p

Hydroxyl-terminated polybutadiene (HTPB) has long been used as a binder in propellants and explosives. However, cured HTPB polyurethanes have not been characterized in a systematic fashion as a function of plasticizer content. In this study, three isocyanate-cured HTPB variants with different amounts of plasticizer were formulated. The materials were characterized across a range of strain rates from 10−3 to 106 s−1. Group interaction modeling (GIM) was used to predict the material behavior based on the underlying structure of the polymer. Increasing the amount of plasticizer was found to reduce the strength of the material across all strain rates. GIM was found to overpredict the modulus but predicted the shock response very well.

Aggregation of mutant superoxide dismutase 1 (SOD1) is a pathological hallmark of a subset of familial ALS patients. However, the possible role of misfolded wild type SOD1 in human ALS is highly debated. To ascertain whether or not misfolded SOD1 is a common pathological feature in non-SOD1 ALS, we performed a blinded histological and biochemical analysis of post mortem brain and spinal cord tissues from 19 sporadic ALS, compared with a SOD1 A4V patient as well as Alzheimer’s disease (AD) and non-neurological controls. Multiple conformation- or misfolded-specific antibodies for human SOD1 were compared. These were generated independently by different research groups and were compared using standardized conditions. Five different misSOD1 staining patterns were found consistently in tissue sections from SALS cases and the SOD1 A4V patient, but were essentially absent in AD and non-neurological controls. We have established clear experimental protocols and provide specific guidelines for working, with conformational/misfolded SOD1-specific antibodies. Adherence to these guidelines will aid in the comparison of the results of future studies and better interpretation of staining patterns. This blinded, standardized and unbiased approach provides further support for a possible pathological role of misSOD1 in SALS.

This chapter focuses on the neuro-cognitive, cognitive and developmental analyses of whole number arithmetic (WNA) learning. It comprises five sections. The first section provides an overview of the working group discussion. Section 7.2 reviews neuro-cognitive perspectives of learning WNA but looks beyond these to explain the transcoding of numerals to number words. In the third section, children’s early mathematics-related competencies in reasoning about quantitative relations, patterns and structures are explored from new theoretical perspectives. Studies presented and discussed in working group 2 are presented in the following section as exemplars of intervention studies. The final section examines methodologies utilized in neuro-cognitive, cognitive and developmental analyses of children’s whole number learning. It discusses study designs and their potentialities and limitations for understanding how children develop competencies with whole numbers as well as task designs in cognitive neuroscience research pertinent to number learning. The chapter concludes with implications for further research and teaching practice.

Additively Manufactured (AM) materials have great potential for producing graded materials, embedded structures and near net complex shapes. AM maraging steel properties have been compared with wrought maraging steel. The comparison featured interrupted tensile tests over a range of temperatures and strain rates. In addition a specially designed Tensile Split Hopkinson Pressure Bar (TSHPB) has been built to test very high strength metals at high strain rates. The results showed that the AM maraging steel was much more ductile than expected and exhibited significant necking under all conditions tested. All the samples exhibited ductile fracture. Although not as ductile as the wrought material, the AM material could be cost effective through economies of scale for complex components. The microstructure contained inclusions which derived from either the powder or the AM process and thus there is significant potential to improve these materials further. A modified Armstrong-Zerilli model was also constructed for these materials and shown to predict the raw experimental data within experimental error using DYNA3D simulations.

With a multitude of potential applications, poly(phosphine-borane)s are an interesting class of polymer comprising main-group elements within the inorganic polymer backbone. A new family of primary alkyl phosphine-borane polymers was synthesised by a solvent-free rhodium catalysed dehydrocoupling reaction and characterised by conventional chemico-physical techniques. The thermal stability of the polymers is strongly affected by the size and shape of the alkyl side chain with longer substituents imparting greater stability. The polymers show substantial stability towards UV illumination and immersion in water however they undergo a loss of alkyl phosphine units during thermal degradation. The polymers exhibit glass transition temperatures (Tg) as low as -70 °C. A group interaction model (GIM) framework was developed to allow the semi-quantitative prediction of Tg values and the properties of the materials in this study were used to validate the model.

This study reports the first 3-year experience of the Eastern Quebec Telepathology Network. Clinical activities started in January 2011 and involved 18 hospitals practicing oncologic surgery in the region. Clinical activities comprised primary diagnosis (including intraoperative consultations (IOC)), expert opinions between two pathologists, continuing education and assistance to macroscopic description. A concordance rate of 98% was found between IOC diagnosis and the final report and the average turnaround time was 20 minutes. Expert opinion reports were completed within 24 hours in 68% of cases. An evaluation of the benefits demonstrates that telepathology prevented interruption of IOC, two-stage surgeries and patient transfers. It also shows that retention and recruitment of surgeons in remote hospitals were facilitated and that professional isolation among pathologists was reduced. Wider adoption of telepathology would require technological improvements and appropriate change management policies. A second phase is underway to expand the service to other regions across the province.

Although most patients undergo muscle biopsies to elucidate the cause of muscle symptoms (weakess, cramping, etc.), many muscle biopsies show relatively few specific alterations on routine staining. Immunohistochemical methods for muscle fibre typing and characterisation of inflammatory cell infiltrates are now well established but the value of other markers is less well documented. A preliminary study of other potentially useful immunohistochemical markers revealed that muscle biopsies in our hospital often contain CD56 and/or D2-40 positive myofibres. This study was extended to a series of 32 biopsies from adult patients (age 21–81, 12 males 20 females), 11 of which showed only minor changes on routine examination. Most cases contained CD56 positive mature fibres; D2-40 positive muscle fibres were more common in cases of inflammatory myopathy. Five cases with minor changes on routine examination showed CD56 and D2-40 staining of otherwise unremarkable myofibres, which might represent reactive changes.LEARNING OBJECTIVESThis presentation will enable the learner to:1.Describe patterns of immunohistochemical staining in reactive muscle fibres2.Discuss the underlying physiology of reactive muscle fibres

The Defence Science and Technology Laboratory sponsored, QinetiQ-led Force Protection Engineering Research Programme has two main strands, applied and underpinning research. The underpinning strand is led by Blastech Ltd. One focus of this research is into the response of geomaterials to threat loading. The programme on locally won fill is split into four main characterisation strands: high-stress (GPa) static pressure–volume; medium-rate pressure–volume (split Hopkinson bar); high-rate (flyer plate) pressure–volume; and unifying modelling research at the University of Sheffield, which has focused on developing a high-quality dataset for locally won fill in low and medium strain rates. With the test apparatus at Sheffield well-controlled tests can be conducted at both high strain rate and pseudo-static rates up to stress levels of 1 GPa. The University of Cambridge has focused on using one-dimensional shock experiments to examine high-rate pressure–volume relationships. Both establishments are examining the effect of moisture content and starting density on emergent rate effects. Blastech Ltd has been undertaking carefully controlled fragment impact experiments, within the dataspace developed by the Universities of Sheffield and Cambridge. The data from experiments are unified by the QinetiQ-led modelling team, to predict material behaviour and to derive a scalable locally won fill model for use in any situation.

While lidar-based forest inventory methods have been widely demonstrated, performances of methods to predict tree diameters with airborne lidar (lidar) are not well understood. One cause for this is that the performance metrics typically used in studies for prediction of diameters can be difficult to interpret, and may not support comparative inferences between sampling designs and study areas. To help with this problem we propose two indices and use them to evaluate a variety of lidar and k nearest neighbor (k-NN) strategies for prediction of tree diameter distributions. The indices are based on the coefficient of determination (R2), and root mean square deviation (RMSD). Both of the indices are highly interpretable, and the RMSD-based index facilitates comparisons with alternative (non-lidar) inventory strategies, and with projects in other regions. K-NN diameter distribution prediction strategies were examined using auxiliary lidar for 190 training plots distribute across the 800 km2 Savannah River Site in South Carolina, USA. We evaluate the performance of k-NN with respect to distance metrics, number of neighbors, predictor sets, and response sets. K-NN and lidar explained 80% of variability in diameters, and Mahalanobis distance with k = 3 neighbors performed best according to a number of criteria., published version, peerReviewed

This paper describes research performed on a polymer-bonded sugar (PBS) consisting of 66% caster sugar in a hydroxyl-terminated polybutadiene (HTPB) binder The mechanical response of the PBS and pure HTPB to applied loading at a strain rate of approximately 2000 s−1at temperatures from −80 to +22°C is presented. The materials were also characterized using dynamic mechanical analysis, X-ray tomography and quasi-static loading. These measurements are required for the development of intermediate strain rate constitutive models of polymer-bonded explosives, for which PBSs are a commonly used mechanical simulant.The current constitutive modelling suffers from a lack of experimental data on well-characterized composites and binders, especially at intermediate strain rates. This is particularly important for understanding the effects of mixing two materials. Applications of such modelling include explosive safety and fundamental understanding of the various deformation mechanisms. In this paper, the dependences of strength and deformation mechanism on temperature, and, in particular, the glass transition temperature of the binder, are shown. Physical damage plays an important role; X-ray tomography scans support debonding as the primary form of damage during room-temperature deformation. These results are in agreement with previous investigations and are discussed in this context.

Amyotrophic Lateral Sclerosis (ALS) is the most frequent motor neuron disease in adults. Classical ALS is characterized by the death of upper and lower motor neurons leading to progressive paralysis. Approximately 10 % of ALS patients have familial form of the disease. Numerous different gene mutations have been found in familial cases of ALS, such as mutations in superoxide dismutase 1 (SOD1), TAR DNA-binding protein 43 (TDP-43), fused in sarcoma (FUS), C9ORF72, ubiquilin-2 (UBQLN2), optineurin (OPTN) and others. Multiple animal models were generated to mimic the disease and to test future treatments. However, no animal model fully replicates the spectrum of phenotypes in the human disease and it is difficult to assess how a therapeutic effect in disease models can predict efficacy in humans. Importantly, the genetic and phenotypic heterogeneity of ALS leads to a variety of responses to similar treatment regimens. From this has emerged the concept of personalized medicine (PM), which is a medical scheme that combines study of genetic, environmental and clinical diagnostic testing, including biomarkers, to individualized patient care. In this perspective, we used subgroups of specific ALS-linked gene mutations to go through existing animal models and to provide a comprehensive profile of the differences and similarities between animal models of disease and human disease. Finally, we reviewed application of biomarkers and gene therapies relevant in personalized medicine approach. For instance, this includes viral delivering of antisense oligonucleotide and small interfering RNA in SOD1, TDP-43 and C9orf72 mice models. Promising gene therapies raised possibilities for treating differently the major mutations in familial ALS cases.

The timing of periodic life cycle events in plants (phenology) is an important factor determining how species and populations will react to climate change. We evaluated annual patterns of basal-area and height growth of coast Douglas-fir (Pseudotusga menziesii var. menziesii (Mirb.) Franco) seedlings from four seed sources that were planted in four diverse environments as part of the Douglas-fir Seed-Source Movement Trial. Stem diameters and heights were measured periodically during the 2010 growing season on 16 open-pollinated families at each study installation. Stem diameters were measured on a subset of trees with electronic dendrometers during the 2010 and 2011 growing seasons. Trees from the four seed sources differed in phenology metrics that described the timing of basal-area and height-growth initiation, growth cessation and growth rates. Differences in the height-growth metrics were generally larger than differences in the basal-area growth metrics and differences among installations were larger than differences among seed sources, highlighting the importance of environmental signals on growth phenology. Variations in the height- and basal-area growth metrics were correlated with different aspects of the seed-source environments: precipitation in the case of height growth and minimum temperature in the case of basal-area growth. The detailed dendrometer measurements revealed differences in growth patterns between seed sources during distinct periods in the growing season. Our results indicate that multiple aspects of growth phenology should be considered along with other traits when evaluating adaptation of populations to future climates.

AT THE START OF THE FIRST FORMAL year of schooling in New South Wales, teachers gather information on a number of aspects of children's numeracy to guide their teaching program. This information is essential to planning teaching activities to meet the needs of all students. This paper reports on some key aspects of number knowledge held by 65 000 children with an average age of 5.3 years when they started in NSW public schools in 2011. The data highlights the diverse yet interconnected number knowledge children possess when they start school, and suggests directions for further enquiry.

Previous studies have demonstrated that light detection and ranging (LiDAR)-derived variables can be used to model forest yield variables, such as biomass, volume, and number of stems. However, the next step is underrepresented in the literature: estimation of forest yield with appropriate confidence intervals. It is of great importance that the procedures required for conducting forest inventory with LiDAR and the estimation precision of such procedures are sufficiently documented to enable their evaluation and implementation by land managers. In this study, we demonstrated the regression estimator, a model-assisted estimator (approximately design-unbiased), using LiDAR-derived variables for estimation of total forest yield. The LiDAR-derived variables are statistics associated with vegetation height and cover. The estimation procedure requires complete coverage of the forest with LiDAR and a random sample of precisely georeferenced field measurement plots. Regression estimation relies on sample-based ordinary least squares (OLS) regression models relating forest yield and LiDAR-derived variables. Estimation was performed using the OLS models and LiDAR-derived variables for the entire population. Regression estimates of basal area, volume, stand density, and biomass were much more precise than simple random sampling estimates (design effects were 0.25, 0.24, 0.44, and 0.27, respectively).

A major objective of tree improvement programs is to identify genotypes that will perform well in operational deployments. Relatively little is known, however, about how the competitive environment affects performance in different types of deployments. We tested whether the genetic composition and density of deployments affect the performance of full-sib families of Douglas-fir (Pseudotsuga meniziesii), and whether traits related to crown morphology could help to explain differences in family performance under competition. Seedlings from eight families were planted in pure-family and three mixed-family composition treatments at high, medium, and low densities (11,954, 2988, and 747 trees·ha−1, respectively). Height (HT), diameter at breast height (DBH), and volume·ha−1 (VOLHA) were measured at ages 8 and 15 years. Significant differences were found among composition treatments in all traits other than VOLHA8 and significant interactions between composition and density treatments were found for all traits at age 15 years. Family ranks for DBH15 and VOLHA15 in pure-family treatments changed considerably among densities, but ranks were more stable for HT15. The performance of two mixed-family treatments differed significantly from the average performances of the same families in pure-family treatments for several traits. Differences in DBH15 among families in high-density, pure-family treatments could be explained in part by differences in crown morphology, with better performance among families with relatively narrow crowns, stout branches, and high leaf area relative to branch length. Our results suggest that the competitive environment has a considerable effect on family performance, and that incorporating crown morphology traits into selection criteria in tree improvement programs may lead to greater productivity of Douglas-fir.

Many land managers are interested in maintaining or restoring plant communities that contain Oregon white oak (OWO, Quercus garryana), yet there is relatively little information available about the species' growth rates and survival to guide management decisions. We used two studies to characterize growth (over multi-year periods and within individual years) and to evaluate the main factors that affect growth and survival. The objective of the first study was to revise the OWO components of the Forest Vegetation Simulator (FVS), a widely-used growth model. We first compiled a large database on growth and survival to develop equations to revise FVS. Diameter growth and survival over multi-year periods were strongly affected by stand density, the competitive position of the tree, tree size, and site productivity. The height growth potential of OWO was predicted from site productivity, stand density and tree size. In the second study, intra-annual patterns of OWO growth were evaluated by precisely measuring stem diameters with band dendrometers. OWO experienced two periods of stem expansion, with the first period likely representing growth (the production of new wood and bark) and the second representing stem rehydration in the fall and winter. As in the first study, growth was strongly affected by the level of competition around each tree. Our results show the sensitivity of Oregon white oak to competition and highlight the need to restore low stand densities in many cases to improve growth and the likelihood of survival.

Introduction A challenge for any physician caring for athletes is determining readiness for return to competition after an injury. A wide variety of performance function tests (PFTs) have been described, but no norms or minimum performance levels exist for any of them. In this study, healthy athletes were given a series of PFTs to complete. We propose that there will be a minimum performance level for each of the PFTs that all athletes can complete. We also propose, for tests that assess the right and left legs independently, that performance of the right leg will consistently be within 10% of the left. Finally, we propose that performance on one of the functional tests will be predictive of function on all the tests. Methods Athletes were put through a testing protocol, beginning with range of motion and progressing through a series of functional ankle tests of increasing difficulty. Right and left leg data were recorded separately for the first five tests. For each test, mean values, ranges, and SDs were calculated. Results Eighty-one athletes completed the protocol. A wide variation existed in performance ability between athletes; the SD for any of the tests was too high to determine a minimum performance threshold. However, when comparing right to left leg in any one athlete, the difference in performance testing was always less than 10%. Furthermore, performance on the side hop test was predictive of performance on the other tests. Discussion A wide range of performance was noted in all the PFTs, so it is not possible to define a minimum threshold. However, performance of an injured leg to within 10% of the opposite (uninjured) leg suggests achievement of normal function. The side hop test might be a good test by itself to represent overall ankle readiness.

Models to predict budburst and other phenological events in plants are needed to forecast how climate change may impact ecosystems and for the development of mitigation strategies. Differences among genotypes are important to predicting phenological events in species that show strong clinal variation in adaptive traits. We present a model that incorporates the effects of temperature and differences among genotypes to predict the timing of budburst of coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco). The main components of the model are (i) functions to calculate the accumulation of chilling units (CU) and forcing units (FU) during dormancy and (ii) a function defining the combinations of CU and FU needed for budburst (the possibility line). The possibility line was fit to data from 59 populations subjected to eight different winter environments. Differences among populations were incorporated into the possibility line using population coefficients that vary the FU required for budburst. Correlations among the population coefficients and variables describing local environments supported the hypothesis that genetic variation in budburst is largely an adaptation to summer drought. The new model can be used to test potential seed transfers as a strategy to mitigate some of the effects of climate change.

The spread and dominance of the invasive native hay-scented fern in the understory is one of the most significant changes that has affected the forest ecosystems in the northeastern United States in the last century. We studied changes in the distribution and dynamics of hay-scented fern at a large scale over a 10-yr period in Pennsylvania. The study included 56 stands covering 1,009 ha in two ecoregions. Hay-scented fern was more widely distributed and occurred at higher densities in the Allegheny Plateau ecoregion vs. the Ridge and Valley. Hay-scented fern abundance was positively associated with overstory red maple abundance in both ecoregions. After overstory removal, the density and distribution of hay-scented fern tended to increase and remain at elevated levels in stands that were not treated with herbicide. Herbicide treatments resulted in temporary reductions in fern densities and created a “window of opportunity” for the establishment of tree regeneration. Nomenclature: Hay-scented fern...

It is late afternoon, and two figures are seen walking slowly along a path that leads through laurel, olives, and vines towards white Colonus, earth's loveliest, where the nightingales liquid notes most haunt the darkness of green glades. They are deep in conversation, yet move with steady, purposeful strides towards an inn that cools its crisp Demesticha in the flowing waters of a spring.

This paper extends a compartmental epidemiological model for HIV transmission and AIDS incidence to include hierarchical and expansion spatial diffusion. An implication of the resultant model is that hierarchical diffusion causes the large infection growth rates of densely populated areas at the top of the central places hierarchy to chain down and dominate small local growth rates during the exponential-growth phase of the epidemic. Also hierarchical diffusion causes a high transient growth rate in the first few years of a local epidemic. The spatial compartmental model fits observed AIDS incidence spatial diffusion patterns in Ohio reasonably well. (EXCERPT)

Growth models for coast Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) are generally based on measurements of stands that are genetically unimproved (or woods-run); therefore, they cannot be expected to accurately project the development of stands that originate from improved seedlots. In this report, we demonstrate how early expected gain and genetic-gain multipliers can be incorporated into growth projection, and we also summarize projected volume gains and other aspects of stand development under different levels of genetic gain, site productivity, and initial planting density. Representative tree lists that included three levels of productivity (site index = 100, 125, and 150 ft; base = 50 years)and three initial planting densities (302, 435, and 602 trees/ac) were projected from ages 10 to 60 years under three scenarios using two regional growth models (Stand Management Cooperative version of ORGANON and the Pacific Northwest variant of the Forest Vegetation Simulator). The two models projected similar percentage volume gains for improved seedlots. Seedlots with a genetic worth (GW) of 5% for height and diameter growth were projected to have volume gains of 3.3–5.8% over woods-run stands at 40 years and 2.1–3.2% at 60 years. Volume gains were projected to approximately double when GW was increased from 5 to 10%.

Most temperate woody plants have a winter chilling requirement to prevent budburst during mid-winter periods of warm weather. The date of spring budburst is dependent on both chilling and forcing; modeling this date is an important part of predicting potential effects of global warming on trees. There is no clear evidence from the literature that the curves of chilling or forcing effectiveness differ by species so we combined our data and published information to develop new curves on the effectiveness of temperature for chilling and forcing. The new curves predict effectiveness over a wide range of temperatures and we suggest both functions may be operating at the same time. We present experimental data from 13 winter environments for 5 genotypes of Douglas-fir (Pseudotsuga menziesii var. menziesii) and use them to test various assumptions of starting and stopping dates for accumulating chilling and forcing units and the relationship between budburst and the accumulation of chilling and forcing units. Chilling started too early to be effective in one treatment but the other 12 environments resulted in budburst from many combinations of chilling and forcing. Previous reports have suggested benefits or cancellations of effects from alternating day/night or periodic temperatures. Our simple models do not include these effects but nevertheless were effective in predicting relationships between chilling and forcing for treatments with a wide range of conditions. Overall, the date of budburst changed only slightly (+1 to −11 days) across a wide range of treatments in our colder test environment (Olympia, WA, USA) but was substantially later (+29 days) in the warmest treatment in our warmer environment (Corvallis, OR, USA). An analysis of historical climate data for both environments predicted a wide range in date to budburst could result from the same mean temperature due to the relative weightings of specific temperatures in the chilling and forcing functions. In the absence of improved understanding of the basic physiological mechanisms involved in dormancy induction and release, we suggest that simple, universal functions be considered for modeling the effectiveness of temperature for chilling and forcing. Future research should be designed to determine the exact shape of the curves; data are particularly lacking at the temperature extremes. We discuss the implications of our data and proposed functions for predicting effects of climate change. Both suggest that the trend toward earlier budburst will be reversed if winter temperatures rise substantially.

A model is presented that calculates the highly nonlinear mechanical properties of polymers as a function of temperature, strain and strain rate from their molecular structure. The model is based upon the premise that mechanical properties are a direct consequence of energy stored and energy dissipated during deformation of a material. This premise is transformed into a consistent set of structure–property relations for the equation of state and the engineering constitutive relations in a polymer by quantifying energy storage and loss at the molecular level of interactions between characteristic groups of atoms in a polymer. The constitutive relations are formulated as a set of analytical equations that predict properties directly in terms of a small set of structural parameters that can be calculated directly and independently from the chemical composition and morphology of a polymer.

Background:Intravascular large cell lymphoma (ILCL) is a diagnostic challenge, with neurological, cutaneous and constitutional symptoms. The natural history is usually an evolution to a comatose state. As invasive procedures are usually required for diagnosis, recognizing the typical clinical pattern is critical since an effective treatment is available.Method:After an extensive literature review of the subject, we report a case of ILCL, analyzing clinical, laboratory, radiological and pathological data. We will also give a special attention to the clinical picture of a conus medullaris (CM) lesion with subsequent encephalopathy in the same patient.Results:We report here a 61-year-old woman with a paraplegia caused by a CM lesion, evolving about one year latter to encephalopathy and eventual coma, with the diagnosis of ILCL confirmed by autopsy. The present case is similar to eight other cases in literature who had CM lesion associated with ILCL, knowing that 80-90% of these patients will eventually evolve to encephalopathy without treatment. Conclusions: ILCL is a recognized but rare cause of coma. Diagnosing it is tremendously important since it is fatal if left untreated. We propose that this specific picture (conus medullaris lesion, eventually evolving to encephalopathy) is quite characteristic and will directly result in better outcome if recognized.

This article presents the first explicit guidelines for regenerating oaks in the central Appalachians. The objectives of this paper are (1) to describe the research foundation on which the guidelines are based and (2) to provide users with the instructions, data collection forms, supplementarytables, and decision charts needed to apply the guidelines in the field. The principal research foundation for the guidelines is a set of quantitative models that estimate, in advance of harvest, a stand's potential to regenerate oak stocking from advance regeneration and stump sprouts. Regeneration potential is measured by the predicted stocking by oak species, expressed as a percentage of full (100%) stocking, in the new stand in its third decade (21–30 years) after overstory removal. An understory classification system is used in conjunction with the models to help identifypotential barriers to regeneration development. Model results and other data on current stand conditions are used in the decision charts to identify prescriptions for achieving a strong component of oak regeneration after stand harvest. Overstory removals are recommended when the stand's oak regeneration potential is adequate to meet management goals. Otherwise, prescriptions designed to enhance seedling-origin oak regeneration potential are recommended.

We developed new equations to predict Oregon white oak (Quercus garryana Dougl. ex Hook.) development within ORGANON, a stand-development model that is widely used in the Pacific Northwest. Tree size, competitive status, crown ratio, and site productivity were statistically significant predictors of growth and mortality. Three scenarios were projected with the new equations, the previous ORGANON model, and the Forest Vegetation Simulator. Compared with the two other models, the new equations predicted greater diameter growth in oak woodland and a greater effect of conifer removal in a conifer-oak stand. The new equations, which are based on considerably more information than previous equations, should give forest managers greater confidence in the ability of ORGANON to estimate the impacts of silvicultural treatments on oaks.