bluuebunny/crossref_metadata_2025_split huggingface dataset:
The multiplicity distribution of Kepler’s exoplanets
Authors: Sandford Emily , Kipping David , Collins Michael 
Published: August 2019

Abstract
The true multiplicity distribution of transiting planet systems is obscured by strong observational biases, leading low-multiplicity systems to be overrepresented in the observed sample. Using the Kepler FGK planet hosts, we employ approximate Bayesian computation to infer the multiplicity distribution by comparing simulated catalogues to the observed one. After comparing a total of 10 different multiplicity distributions, half of which were two-population models, to the observed data, we find that a single-population model following a Zipfian distribution is able to explain the Kepler data as well as any of the dichotomous models we test. Our work provides another example of a way to explain the observed Kepler multiplicities without invoking a dichotomous planet population. Using our preferred Zipfian model, we estimate that an additional $2393_{-717}^{+904}$ planets likely reside in the 1537 FGK Kepler systems studied in this work, which would increase the planet count by a factor of $2.22_{-0.36}^{+0.46}$. Of these hidden worlds, $663_{-151}^{+158}$ are expected to reside in ostensibly single transiting planet systems, meaning that an additional planet(s) is expected for approximately 1-in-2 such Kepler systems.
The flyby anomaly and the gravitational–magnetic field induced frame-dragging effect around the Earth
Authors: Mirza Babur M 
Published: August 2019

ABSTRACTThe anomalous energy difference observed during the Earth flybys is modelled here as a dynamical effect resulting from the coupling of the gravitational and the magnetic fields of the Earth. The theoretical analysis shows that general relativistic frame-dragging can become modified under the Earth’s magnetic field by orders of magnitude. For 12 flyby cases, including the null results reported in some recent flybys, the predicted velocities correspond to the observed velocities within the observational error. The gravitomagnetic effect is also shown to account for the linear distance relation, time-variation of the anomalous energy, and the reduction in the anomalous velocity for high-altitude flybys near the Earth.
Genome reading by the NF-κB transcription factors
Authors: Mulero Maria Carmen , Wang Vivien Ya-Fan , Huxford Tom , Ghosh Gourisankar 
Published: August 2019

AbstractThe NF-κB family of dimeric transcription factors regulates transcription by selectively binding to DNA response elements present within promoters or enhancers of target genes. The DNA response elements, collectively known as κB sites or κB DNA, share the consensus 5′-GGGRNNNYCC-3′ (where R, Y and N are purine, pyrimidine and any nucleotide base, respectively). In addition, several DNA sequences that deviate significantly from the consensus have been shown to accommodate binding by NF-κB dimers. X-ray crystal structures of NF-κB in complex with diverse κB DNA have helped elucidate the chemical principles that underlie target selection in vitro. However, NF-κB dimers encounter additional impediments to selective DNA binding in vivo. Work carried out during the past decades has identified some of the barriers to sequence selective DNA target binding within the context of chromatin and suggests possible mechanisms by which NF-κB might overcome these obstacles. In this review, we first highlight structural features of NF-κB:DNA complexes and how distinctive features of NF-κB proteins and DNA sequences contribute to specific complex formation. We then discuss how native NF-κB dimers identify DNA binding targets in the nucleus with support from additional factors and how post-translational modifications enable NF-κB to selectively bind κB sites in vivo.
At least two molecules of the RNA helicase Has1 are simultaneously present in pre-ribosomes during ribosome biogenesis
Authors: Gnanasundram Sivakumar Vadivel , Kos-Braun Isabelle C , Koš Martin 
Published: August 2019

Abstract
The RNA helicase Has1 is involved in the biogenesis of both small and large ribosomal subunits. How it performs these separate roles is not fully understood. Here we provide evidence that at least two molecules of Has1 are temporarily present at the same time in 90S pre-ribosomes. We identified multiple Has1 binding sites in the 18S, 5.8S and 25S rRNAs. We show that while the Has1 catalytic activity is not required for binding to 5.8S/25S region in pre-rRNA, it is essential for binding to 18S sites. After the cleavage of pre-rRNA at the A2 site, Has1 remains associated not only with pre-60S but, unexpectedly, also with pre-40S ribosomes. The recruitment to 90S/pre-40S and pre-60S ribosomes is mutually independent. Our data provides insight into how Has1 performs its separate functions in the synthesis of both ribosomal subunits.
Comparing N-Tree Distance Sampling with Point and Plot Sampling in Northern Michigan Forest Types
Authors: Lessard Veronica , Reed David D. , Monkevich Nicholas 
Published: August 2019

Abstract
This study demonstrates the utility of n-tree distance sampling as an alternative to the more common point and plot sampling. This practical demonstration was conducted in Michigan's Upper Peninsula in three forest types: northern hardwood stands, plantation red pine stands, and clumped, mixed hardwood stands. Seven types of field sampling techniques were used: 1/5 ac and 1/10 ac fixed radius plot sampling, BAF 10 and BAF 20 variable radius point sampling, and n-tree distance sampling of 3, 5, and 7 trees. Estimates of mean board foot volume, cords, basal area, and number of trees per acre produced by n-tree distance sampling are biased, but when a bias correction factor is applied to the northern hardwood estimates, the results are equivalent to estimates from point and plot sampling. Investigation of bias in the plantation and clumped forests is ongoing. N-tree distance sampling is cost-competitive with the more traditional point and plot northern hardwoods. North. J. Appl. For. 11(1):12-16.
State Nonpoint Source Programs Affecting Forestry: The 12 Northeastern States
Authors: Irland Lloyd C. , Connors James F. 
Published: August 2019

Abstract
Programs addressing nonpoint source (NPS) water pollution impacts in forestry cover a wide range of activities in the Northeast. While state water program managers rate forestry-related sedimentation as a low priority problem, monitoring data to verify this are scanty. Most states have cooperative arrangements between environmental agencies which handle enforcement and forestry agencies which deliver NPS programs. Field assessments show that properly installed BMPs are effective in minimizing sedimentation from forestry activities. Only a few field reviews of compliance have been done. These show that while noncompliance is significant, and erosion does occur, the water quality impacts appear to be minimal. While significant progress has been made, it will be difficult to maintain program momentum in the extremely difficult fiscal climate faced by the northeastern states. Also, the research base for defining more cost-effective practices and administrative programs has important gaps. North. J. Appl. For. 11(1):5-11.
Partial Calibration of "ONTWIGS": A Forest Growth and Yield Projection System Adapted for Ontario
Authors: Payandeh Bijan , Papadopol Pia 
Published: August 2019

Abstract
"ONTWIGS" (an adaptation of "LSTWIGS" for Ontario), was partially calibrated for permanent plots data sets from northern Ontario. Stand attributes used for calibration were quadratic mean diameter, number of trees, and basal area/ha. Simple local calibration was accomplished by adjusting tree survival and potential diameter growth coefficients so as to reduce the prediction errors to within 10% of the actual values over a 5-yr period. This resulted in prediction errors ranging from -9.9 to 6.9%, but with an overall average of only: -1.4, 1.0, and 0.2% for the spruce fir data; from -8.5 to 2.8%, but with an overall average of only -0.7, 0.5, and 0.4% for a black spruce drainage and fertilization experiment; and from -6.6 to 9.8%, but with an overall average of only -1.7, 0.0, and -1.8% for an unthinned red pine plantation for number of trees/ha, quadratic mean diameter, and basal area/ha, respectively. Results indicate that "ONTWIGS" may be locally calibrated through simple procedures to increase its prediction accuracy to ±5% of the observed stand attributes, averaging less than 3% for the major timber species in northern Ontario and for short to medium projection periods. However, the uncalibrated model should be used with caution for short terms, only and where no other projection tools are available. More extensive calibrations of "ONTWIGS" on larger and more representative data sets are currently underway. North. J. Appl. For. 11(2):41-46.
Postfire Tree Mortality in Relation to Wildfire Severity in Mixed Oak Forests in the Blue Ridge of Virginia
Authors: Regelbrugge John C. , Smith David Wm. 
Published: August 2019

Abstract
Tree mortality in relation to fire severity was investigated in eight mixed oak stands in the second growing season following the 1900 ha Big Run Fire in May 1986, in Shenandoah National Park in the Blue Ridge of Virginia. Plots were located in four stands each burned by high- and low-severity fire. Prefire stands were evenaged (55-60 yr), of medium quality (upland oak 50 yr site index 18-20 m ), and dominated by chestnut oak, scarlet oak, northern red oak and pignut hickory. High-severity fire top-killed 67% of stand basal area and 81% of the trees, whereas low-severity fire top-killed 8% of stand basal area and 15% of the trees. Height of stem-bark char accounted for 93 % and 96% of the variation in fire-killed basal area and number of trees, respectively. Logistic regression models relating probability of top-kill of individual trees with tree dbh and height of stem-bark char were developed for chestnut oak, scarlet oak, northern red oak, black oak, pignut hickory, red maple, blackgum, and serviceberry. Regression diagnostics indicated that the models predicted well for all species, with 79 to 95% concordance between predicted probabilities and observed outcomes. The models demonstrate the interaction of species-specific fire resistance, tree size, and fire severity in determining fire induced top-kill. These models can be used to estimate postfire mortality for a variety of purposes, including planning postwildfire timber salvage and regeneration operations, planning prescribed fires, and ecosystem process modeling. North. J. Appl. For. 11(3):90-97.
Strip Thinning and Spacing Increases Tree Growth of Young Black Spruce
Authors: Burns Joanie , Puettmann Klaus J. , Perala Don 
Published: August 2019

Abstract
Two different thinning methods were applied to three 6- or 7-yr-old black spruce stands in northern Minnesota which were measured after 20 yr. Overall, thinning improved the growing conditions for crop trees. Strip thinning with a 0.6 m leave strip and three widths of cleared strips (1.5 m, 2.1 m, and 2.7 m), and spacing to 1.5 m, 2.1 m, and 2.7 m resulted in reduced numbers of crop trees, but with larger diameters and, in the spacing thinned plots, greater heights. Because of these contradicting trends, stand volume was unaffected by thinning. Crop tree growth was not affected by the width of the cleared strip, but the distances between the leave trees in the square spacing were positively related to the increased growth response after thinning. The study is still too young to evaluate the economic feasibility of both thinning treatments, but shorter rotations or substantially increased volume seem possible by early thinnings of black spruce. North. J. Appl. For. 13(2):68-72.
Spruce Budworm Defoliation and Growth Loss in Young Balsam Fir: Estimation of Volume Growth Based on Stem Analysis and Increment Cores at Breast Height
Authors: Piene Harald , D'Amours Janine , Bray Alan A. 
Published: August 2019

Abstract
Comparisons of estimates of volume and volume increment, based on increment cores sampled at breast height and on stem analysis, were made in a young balsam fir stand that had been defoliated by spruce budworm. Use of increment cores is not recommended to estimate individual tree growth, because large errors, ranging from 20.9 to 57.2%, and error variability can be expected. The inability, when using increment cores, to estimate basal area is the major source of this variation. Although large uncertainties are associated with future growth predictions, on a per ha basis, changes over time based on increment cores may in some instances give comparable results to those based on stem analysis due to the canceling effect of trees being approximately equally overestimated and underestimated. However, a prerequisite is that the defoliation history and the year of individual tree death are known in detail to aid in the correct dating of ring widths. North. J. Appl. For. 13(2):73-78.
Effects of Long-Term Military Training Traffic on Forest Vegetation in Central Minnesota
Authors: Greene Thomas A. , Nichols Thomas J. 
Published: August 2019

Abstract
We studied vegetation on traveled and untraveled loamy sands on military training land in central Minnesota to identify traffic-induced differences in species composition, cover, diversity, growth rates, and tree condition. Long-term military traffic resulted in a 23% reduction in overstory basal area, a 14% reduction in canopy cover, a 43% reduction in overstory stem density, and a 20% reduction in overstory species diversity compared with adjacent untraveled areas. Most of the overstory basal area reduction was accounted for by a 78% reduction in quaking aspen basal area. Crown dieback was not significantly affected by traffic. Midstory tree and shrub density was 70% lower on traveled areas. Herbaceous vegetation was denser and more diverse in traveled areas. Traffic caused a six-fold increase in bare soil area on sloping soils, but had no effect on bare soil area on level sites. Our data suggest that moderate, long-term traffic on loamy sand soils results in a relatively stable system which can be thought of as in equilibrium between traffic, natural regenerative forces, and management activities. We caution managers that quaking aspen may decline under traffic, and remind them of the risk of erosion on traveled slopes. North. J. Appl. For. 13(4): 157-163.
Testing Lake States TWIGS: Five-Year Growth Projections for Upland Hardwoods in Northern Lower Michigan
Authors: Guertin Patrick J. , Ramm C. W. 
Published: August 2019

Abstract
Five-year diameter growth, basal area growth, and mortality for five upland hardwood species in northern Lower Michigan were compared to projections from Lake States TWIGS. The species studied were northern red oak, white oak, other red oak (pin oak and black oak combined), sugar maple, and red maple. The validation data consisted of individual tree measurements from 44 stands across 10 ecological land types on the Manistee National Forest. The stands were measured in 1986 and 1991; during this time interval stands experienced a drought and outbreaks of leaf defoliators. For individual dbh classes, 5 yr diameter growth was predicted within ± 0.3 in. for all species. Mean errors for BA projections were within ± 5 ft²/ac for all species, and mean error for trees/ac ranged from - 33 for other red oak to + 16 for sugar maple. Although precision was variable, Lake States TWIGS provided accurate predictions of 5 yr diameter growth for the five species tested. Projections of mortality were less accurate. North. J. Appl. For. 13(4):00-00.
Sample Sizes Required To Estimate Defoliation of Spruce and Balsam Fir Caused by Spruce Budworm Accurately
Authors: MacLean David A. , MacKinnon Wayne E. 
Published: August 2019

Abstract
Data from the assessment of current defoliation levels on 172,000 individual shoots from 6890 midcrown branches sampled from balsam fir and spruce stands were used to define sampling protocols for assessing defoliation caused by spruce budworm. The method was based on sampling one midcrown branch from each of x host trees per stand, and assessing defoliation of y individual shoots per branch. Both the number of shoots per branch and the number of branches required per stand varied with host species (balsam fir, white spruce, or red-black spruce) and with average defoliation level. Sample sizes required to estimate mean defoliation with 90% confidence that the confidence interval is ±10% ranged from 7 to 24 branches per stand and from 17 to 58 shoots per branch, with the largest samples required at moderate (31-70%) defoliation levels. Estimated costs of shoot and branch sampling and processing ranged from $40-110/stand, based on a 90% confidence level salary rate of $12(Can.)/hr, and excluding travel costs. Results can be applied using a preliminary assessment to determine the general defoliation level, which along with species, determines the required sample size. North. J. Appl. For. 15(3):135-140.
Tree Shelters Reduced Growth and Survival of Underplanted Red Oak Seedlings in Southern Iowa
Authors: Bardon Robert E. , Countryman David W. , Hall Richard B. 
Published: August 2019

Abstract
A major concern in the management of northern red oak (Quercus rubra L.) is the difficulty in regenerating stands that have dense understories of shade tolerant species. A replicated study in southern Iowa indicated that over a 5 yr period, tree shelters have a major impact on establishment of underplanted, 1-0, northern red oak bareroot stock. Sheltered seedlings had increased height growth during the first 3 growing seasons. But during the next 2 growing seasons, annual height growth of sheltered seedlings declined to a level of annual height growth similar to that of nonsheltered seedlings. After 5 growing seasons, sheltered seedlings were approximately 30 cm taller than nonsheltered seedlings. Sheltered and nonsheltered seedlings were one-third to two-thirds the height of the shelters. At the end of the fifth growing season, total mortality for sheltered seedlings was 40 and 55%, whereas for nonsheltered seedlings, mortality was 26 and 28% at the McNay and Stephens sites, respectively. Tree shelters may be a viable alternative in open areas (e.g., clearcuts or plantations), but in this study, tree shelters reduced both growth and survival when used to protect underplanted, 1-0, red oak seedlings. North. J. Appl. For. 16(2):103-107.
Wildlife Communities Associated with Even-Aged Reproduction Stands in Two State Forests of Pennsylvania
Authors: Boardman Leigh Ann , Yahner Richard H. 
Published: August 2019

Abstract
The effects of even-aged forest management on wildlife have been studied extensively in the northeastern United States. The Pennsylvania Bureau of Forestry recently adopted a new forest management practice termed "even-aged reproduction stands with reservation guidelines," hereafter termed EAR stands, which is intended to replace clearcutting as the primary method of even-aged forest management. We examined wildlife communities (breeding birds and small mammals) in 16 stands (8 EAR stands and 8 reference) in central Pennsylvania from February to October 1995. Species richness and abundances of total birds, foraging guilds, and individual species did not differ (P > 0.05) between large (> 30) and small (< 20 ha) EAR stands. Bird species richness was similar between EAR and reference stands, but abundances of total birds, ground-shrub foragers,common yellowthroats (Geothylpis trichas), and chipping sparrows (Spizella passerina) were significantly higher in EAR than in reference stands. Conversely, abundances of canopy-sallier foragers and red-eyed vireos (Vireo olivaceus) were considerably higher (P < 0.05) in reference than EAR stands. Abundance of the white-footed mouse (Peromyscus leucopus) was significantly (P < 0.01) higher in small compared to large EAR stands but was similar between EAR and reference stands. Because of the concerns about forest fragmentation, we recommend that EAR stands be less than 40 ha in size, which is typical of those created by the Pennsylvania Bureau of Forestry. Overstory trees and snags in EAR stands serve as important substrates for breeding birds. Furthermore, EAR guidelines promote regeneration and growth of a dense layer of vegetation near ground level which is beneficial to wildlife. North. J. Appl. For. 16(2):89-95.
Measuring Stocking in Northern Red Oak Stands in Wisconsin
Authors: McGill David W. , Rogers Robert , Martin A. Jeff , Johnson Paul S. 
Published: August 2019

Abstract
Stocking equations and charts for stands dominated by northern red oak were developed from data collected on 66 plots in 52 northern red oak stands in Wisconsin. In all plots, northern red oak was the dominant species. Tolerant species such as sugar maple and red maple usually formed a subcanopy. We used the tree-area ratio method for measuring stocking. However, we treated the tolerant subcanopy as a separate component of stocking. This facilitated defining average maximum relative stand density (100% stocking)for the main canopy or the main canopy and subcanopy combined.This approach is based on the assumption that shade tolerant species can exploit resources in spatial strata that are unexploited by the mid-tolerant red oak. The resulting stocking equations and charts can provide an objective basis for evaluating stocking of northern red oak stands in Wisconsin.North. J. Appl. For. 16(3):144-150.
An Assessment of Stand Damage Following Timber Harvests in West Virginia
Authors: Hassler Curt C. , Grushecky Shawn T. , Fajvan Mary Ann 
Published: August 2019

Abstract
Fixed plot sampling was used to measure residual stand damage on 101 harvested stands in West Virginia. Damage was categorized for roots, base, bole, and crown components of all trees 4 in. dbh and greater. The level of damage was correlated to both preharvest and residual stand densities. Equations were developed to estimate stand damage, based on preharvest and residual stand basal area and trees per acre. These equations were found to reasonably estimate levels of stand damage from previous studies in partial/selection cuts, but not in thinnings. North. J. Appl. For. 16(4):191-196.
Glaze Damage in a Young Yellow Birch Stand in Southern Quebec, Canada
Authors: Zarnovican Richard 
Published: August 2019

Abstract
The relationships between three hardwood species, social position of trees, precommercial thinning treatment and ice storm damage were studied in a young hardwood stand in southern Quebec. The association between these variables was determined using log-linear modeling. Severity of the glaze damage was much higher for yellow birch than for sugar maple and white ash. As for the thinning treatment, yellow birch had the highest damage when heavy thinning from below was used. North. J. Appl. For. 18(1):14–18
Reserve Strip Method as an Alternative for Regenerating Eastern Hemlock
Authors: Goerlich Daniel L. , Nyland Ralph D. , Zhang Lianjun , Sage Richard W. 
Published: August 2019

Abstract
Realization that eastern hemlock (Tsuga canadensis L.) provides both a good yield of softwood material and valuable cover for wildlife has increased interest in successfully regenerating this species. In the central Adirondack Mountains of New York State, the outcome is variable. The study investigated the potential to regenerate hemlock in the reserve area between clearcut strips. Data show that reserve strip widths of about two-thirds the height of overstory trees appeared best for regeneration and recruitment of eastern hemlock to taller height classes. Wider reserve strip widths allow regeneration of hemlock seedlings but inadequate recruitment to larger sizes. Poisson regression indicated that reserve strip width significantly influences the establishment of hemlock seedlings greater than 6 in. high. North. J. Appl. For. 18(3):69–73.