bluuebunny/crossref_metadata_2025 huggingface dataset:
Cuticular Permeability, Percent Body Water Loss, and Relative Humidity Equilibria Comparisons of Four Termite Species
Authors: Zukowski John , Su Nan-Yao
Published: August 2019

This study compared percentage of total body water (%TBW), water loss rate under desiccative conditions, and cuticular permeability (CP) of four termite species (Order: Blattodea, Infraorder: Isoptera) from different habitats, including one subterranean termite, Coptotermes formosanus Shiraki (Blattodea: Rhinotermitidae), one dampwood termite, Neotermes jouteli (Banks) (Blattodea: Kalotermitidae), one ‘wetwood’ termite, Cryptotermes cavifrons Banks (Blattodea: Kalotermitidae), and one drywood termite, Cryptotermes brevis Walker (Blattodea: Kalotermitidae). There was no consistent pattern associated with the habitat relative humidity (RH) levels and the %TBW among the four termite species tested. Because C. formosanus forage for food, its lowest %TBW may be due to its ability to access water sources, and its need to be more mobile than kalotermitids that remain in wood. Body water loss rate and CP were lower for xeric species such as Cr. brevis than hydric species such as N. jouteli. An RH equilibrium represents the capacity of termite water retention mechanisms that may include the physical structure of cuticular layers, behavioral manipulation of natural openings, and physiological means. As with water loss rate and CP data, RH equilibria were lower for xeric species such as Cr. brevis than hydric species such as N. jouteli. Moreover, RH equilibria for dead individuals of the four termite species were significantly higher than those of live individuals, indicating dead termites lost more water after losing their physiological and behavioral means of retaining water. RH equilibria represent termites’ capability in water retention, and there is a strong linear relationship between RH equilibria and CP values. Hence, RH equilibria may offer simpler alternatives to CP estimates.
Stomach nematodes of cotton rats: parasites, commensals, or mutualists?
Authors: Bergstrom Bradley J , Rose Robert K , Bellows A Scott
Published: August 2019

We related presence and burden of stomach nematodes to body mass and reproductive allocation in hispid cotton rats (Sigmodon hispidus) from two long-running field studies in Virginia (1983–1984, n = 286; and 1988–1990, n = 425) and one from Georgia 1987–1989 (n = 459). Eighty percent of rats from the earlier Virginia sample were infected, with mean nematode mass of 1,311 mg. In the later samples, 23% (Virginia) and 33% (Georgia) were infected with mean nematode mass of 493 and 769 mg, respectively. Presence of nematodes was positively correlated with host body length for each sex in each sample. We used analysis of covariance to examine length-adjusted residuals for presence of nematodes and mass of nematodes for association with somatic and reproductive response variables. Both body and reproductive masses were either positively associated or not related to nematode presence in the two low-prevalence samples, and either negatively associated or not related to nematode presence in the high-prevalence sample. No relationships were detected between host mass and nematode mass per host in either sex in any sample. There was no effect of nematode presence on litter size of pregnant females, but there was a positive effect of nematode mass on litter size in Georgia. Recent theory provides several possible explanations for such neutral-to-positive effects of stomach nematodes on host fitness, including the evolution of host tolerance to the parasites, fecundity compensation by the hosts, and positive effects on host health via immune modulation.
Is Myotis lavali (Chiroptera, Vespertilionidae) endemic to the South American dry diagonal?
Authors: Weber Marcelo M , Novaes Roberto Leonan M , Delgado-Jaramillo Mariana , Barbier Eder , Cláudio Vinícius C , Bernard Enrico , Moratelli Ricardo
Published: August 2019

Myotis lavali was described from the M. nigricans complex based on museum specimens from the Caatinga of northeastern Brazil. Current records of the species from about 10 localities suggest that M. lavali seems to occur throughout the South American dry corridor, with peripheral records in the Atlantic Forest. Based on new distribution records, we assess if M. lavali is endemic to the South American dry diagonal corridor through species distribution modeling using an ensemble approach. We obtained 35 occurrences for the species and built a consensus scenario based on 12 algorithms to model its distribution. Even using different thresholds to assign presence and absence of M. lavali, 95–99% of its predicted distribution is within the dry corridor, with few areas in the boundary of the Atlantic Forest, especially in deciduous forests. Therefore, our results support that M. lavali is indeed very likely restricted to the dry diagonal and, although it occupies forested areas, the core of its distribution lies in the Caatinga and in the Cerrado regions of Brazil.
Accuracy of Risk Estimates from the iPrevent Breast Cancer Risk Assessment and Management Tool
Authors: Phillips Kelly-Anne , Liao Yuyan , Milne Roger L , MacInnis Robert J , Collins Ian M , Buchsbaum Richard , Weideman Prue C , Bickerstaffe Adrian , Nesci Stephanie , Chung Wendy K , Southey Melissa C , Knight Julia A , Whittemore Alice S , Dite Gillian S , Goldgar David , Giles Graham G , Glendon Gord , Cuzick Jack , Antoniou Antonis C , Andrulis Irene L , John Esther M , Daly Mary B , Buys Saundra S , Hopper John L , Terry Mary Beth ,   for the kConFab Investigators
Published: August 2019

Background

iPrevent is an online breast cancer (BC) risk management decision support tool. It uses an internal switching algorithm, based on a woman’s risk factor data, to estimate her absolute BC risk using either the International Breast Cancer Intervention Study (IBIS) version 7.02, or Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm version 3 models, and then provides tailored risk management information. This study assessed the accuracy of the 10-year risk estimates using prospective data.

Methods

iPrevent-assigned 10-year invasive BC risk was calculated for 15 732 women aged 20–70 years and without BC at recruitment to the Prospective Family Study Cohort. Calibration, the ratio of the expected (E) number of BCs to the observed (O) number and discriminatory accuracy were assessed.

Results

During the 10 years of follow-up, 619 women (3.9%) developed BC compared with 702 expected (E/O = 1.13; 95% confidence interval [CI] =1.05 to 1.23). For women younger than 50 years, 50 years and older, and BRCA1/2-mutation carriers and noncarriers, E/O was 1.04 (95% CI = 0.93 to 1.16), 1.24 (95% CI = 1.11 to 1.39), 1.13 (95% CI = 0.96 to 1.34), and 1.13 (95% CI = 1.04 to 1.24), respectively. The C-statistic was 0.70 (95% CI = 0.68 to 0.73) overall and 0.74 (95% CI = 0.71 to 0.77), 0.63 (95% CI = 0.59 to 0.66), 0.59 (95% CI = 0.53 to 0.64), and 0.65 (95% CI = 0.63 to 0.68), respectively, for the subgroups above. Applying the newer IBIS version 8.0b in the iPrevent switching algorithm improved calibration overall (E/O = 1.06, 95% CI = 0.98 to 1.15) and in all subgroups, without changing discriminatory accuracy.

Conclusions

For 10-year BC risk, iPrevent had good discriminatory accuracy overall and was well calibrated for women aged younger than 50 years. Calibration may be improved in the future by incorporating IBIS version 8.0b.
‘Perfect Vision’: An Examination of the Role of Census and Profiling Practices in Visualizing and Crafting Refugee ‘Groups’ under Contemporary Group-resettlement Programmes
Authors: Batarseh Robert Christian
Published: August 2019

This article demonstrates how the characteristically visual practices of boundary-making around prospective refugee groups comprise an important and instrumentalized version of what Rogers Brubaker (2004) calls ‘groupism’—the assumption that ‘discrete, sharply differentiated, internally homogeneous and externally bounded groups’ are the ‘basic constituents of social life’ (2004: 8). Unlike individual resettlement, group-resettlement schemes (known as ‘Group Processing’ in Canada, ‘Priority-2 group referrals’ in the United States and the ‘Group Methodology’ at the United Nations High Commissioner for Refugees (UNHCR)) involve the resettlement of entire refugee groups. Preoccupations with security and the possibility of identity fraud in these programmes have led to a preference for what are perceived as easily identifiable, finite and homogenous refugee groups. Census and profiling practices permit authorities to visualize and draw boundaries around these types of groups. These practices are the preconditions for the writing of specific narratives of risk, persecution and flight in UNHCR group profiles. An examination of group resettlement reveals how officials do not just choose between pre-existing refugee groups based on racial, national and ethnic categories, but rather attempt to construct an idealized conception of groups reflected in Brubaker’s notion of groupism.
The novel fungal CYP51 inhibitor VT-1598 displays classic dose-dependent antifungal activity in murine models of invasive aspergillosis
Authors: Garvey E P , Sharp A D , Warn P A , Yates C M , Atari M , Thomas S , Schotzinger R J
Published: August 2019

Aspergillus spp. infections remain a global concern, with ∼30% attributable mortality of invasive aspergillosis (IA). VT-1598 is a novel fungal CYP51 inhibitor designed for exquisite selectivity versus human CYP enzymes to achieve a maximal therapeutic index and therefore maximal antifungal efficacy. Previously, its broad-spectrum in vitro antifungal activity was reported. We report here the pharmacokinetics (PK) and pharmacodynamics (PD) of VT-1598 in neutropenic mouse models of IA. The plasma area-under-the-curve (AUC) of VT-1598 increased nearly linearly between 5 and 40 mg/kg after 5 days of QD administration (155 and 1033 μg*h/ml, respectively), with a further increase with 40 mg/kg BID dosing (1354 μg*h/ml). When A. fumigatus isolates with in vitro susceptibilities of 0.25 and 1.0 μg/ml were used in a disseminated IA model, VT-1598 treatment produced no decrease in kidney fungal burden at QD 10 mg/kg, intermediate decreases at QD 20 mg/kg and maximum or near maximum decreases at 40 mg/kg QD and BID. The PK/PD relationships of AUCfree/MIC for 1-log killing for the two strains were 5.1 and 1.6 h, respectively, similar to values reported for approved CYP51 inhibitors. In a survival study where animals were observed for 12 days after the last treatment, survival was 100% at the doses tested (20 and 40 mg/kg QD), and fungal burden remained suppressed even though drug wash-out was complete. Similar dose-dependent reductions in lung fungal burden were observed in a pulmonary model of IA. These data strongly support further exploration of VT-1598 for the treatment of this lethal mold infection.
A study of stellar orbit fractions: simulated IllustrisTNG galaxies compared to CALIFA observations
Authors: Xu Dandan , Zhu Ling , Grand Robert , Springel Volker , Mao Shude , van de Ven Glenn , Lu Shengdong , Wang Yougang , Pillepich Annalisa , Genel Shy , Nelson Dylan , Rodriguez-Gomez Vicente , Pakmor Rüdiger , Weinberger Rainer , Marinacci Federico , Vogelsberger Mark , Torrey Paul , Naiman Jill , Hernquist Lars
Published: August 2019

Motivated by the recently discovered kinematic ‘Hubble sequence’ shown by the stellar orbit-circularity distribution of 260 CALIFA galaxies, we make use of a comparable galaxy sample at z = 0 with a stellar mass range of $M_{*}/\mathrm{M}_{\odot }\in [10^{9.7},\, 10^{11.4}]$ selected from the IllustrisTNG simulation and study their stellar orbit compositions in relation to a number of other fundamental galaxy properties. We find that the TNG100 simulation broadly reproduces the observed fractions of different orbital components and their stellar mass dependences. In particular, the mean mass dependences of the luminosity fractions for the kinematically warm and hot orbits are well reproduced within model uncertainties of the observed galaxies. The simulation also largely reproduces the observed peak and trough features at $M_{*}\approx 1\rm {-}2\times 10^{10}\, \mathrm{M}_{\odot }$ in the mean distributions of the cold- and hot-orbit fractions, respectively, indicating fewer cooler orbits and more hotter orbits in both more- and less-massive galaxies beyond such a mass range. Several marginal disagreements are seen between the simulation and observations: the average cold-orbit (counter-rotating) fractions of the simulated galaxies below (above) $M_{*}\approx 6\times 10^{10}\, \mathrm{M}_{\odot }$ are systematically higher than the observational data by $\lesssim 10{{\ \rm per\ cent}}$ (absolute orbital fraction); the simulation also seems to produce more scatter for the cold-orbit fraction and less so for the non-cold orbits at any given galaxy mass. Possible causes that stem from the adopted heating mechanisms are discussed.
Monte Carlo simulations of polarimetric and light variability from corotating interaction regions in hot stellar winds
Authors: Carlos-Leblanc Danny , St-Louis Nicole , Bjorkman Jon E , Ignace Richard
Published: August 2019

We use a 3D Monte Carlo radiative transfer code to study the polarimetric and photometric variability from stationary corotating interaction regions (CIR) in the wind of massive stars. Our CIRs are approximated by Archimedean spirals of higher (or lower) density formed in a spherical wind originating from the star and we also made allowance for a bright Gaussian spot at the base of the CIR. Comparing results from our code to previous analytical calculations in the optically thin case, we find differences which we attribute mainly to a better estimation of the total unpolarized flux reaching the observer. In the optically thick case, the differences with the analytical calculations are much larger, as multiple scattering introduces additional complexities including occultation effects. The addition of a Gaussian spot does not alter the shape of the polarization curve significantly but does create a small excess in polarization. On the other hand, the effect can be larger on the light curve and can become dominant over the resulting CIR, depending on the spot parameters and density of the wind.
Deep late-time observations of the supernova impostors SN 1954J and SN 1961V
Authors: Patton Rachel A , Kochanek C S , Adams S M
Published: August 2019

SN 1954J in NGC 2403 and SN 1961V in NGC 1058 were two luminous transients whose definitive classification as either non-terminal eruptions or supernovae remains elusive. A critical question is whether a surviving star can be significantly obscured by dust formed from material ejected during the transient. We use three lines of argument to show that the candidate surviving stars are not significantly optically extinct (τ ≲ 1) by dust formed in the transients. First, we use SED fits to new HST optical and near-IR photometry. Secondly, neither source is becoming brighter as required by absorption from an expanding shell of ejected material. Thirdly, the ejecta masses implied by the Hα luminosities are too low to produce significant dust absorption. The latter two arguments hold independent of the dust properties. The Hα fluxes should also be declining with time as t−3, and this seems not to be observed. As a result, it seems unlikely that recently formed dust can be responsible for the present faintness of the sources compared to their progenitors, although this can be verified with the James Webb Space Telescope. This leaves three possibilities: (1) the survivors were misidentified; (2) they are intrinsically less luminous; (3) SN 1954J and SN 1961V were true supernovae.
XMM-Newton observations of the symbiotic recurrent nova T CrB: evolution of X-ray emission during the active phase
Authors: Zhekov Svetozar A , Tomov Toma V
Published: August 2019

We present an analysis of the XMM-Newton observations of the symbiotic recurrent nova T CrB, obtained during its active phase which started in 2014–2015. The XMM-Newton spectra of T CrB have two prominent components: a soft one (0.2–0.6 keV), well represented by blackbody emission, and a heavily absorbed hard component (2–10 keV), well matched by optically-thin plasma emission with high temperature (kT ≈ 8 keV). The XMM-Newton observations reveal evolution of the X-ray emission from T CrB in its active phase. Namely, the soft component in its spectrum is decreasing with time, while the opposite is true for the hard component. Comparison with data obtained in the quiescent phase shows that the soft component is typical only for the active phase, while the hard component is present in both phases but it is considerably stronger in the quiescent phase. Presence of stochastic variability (flickering) on time-scales of minutes and hours is confirmed both in X-rays and UV (UVM2 filter of the XMM-Newton optical monitor). On the other hand, periodic variability of 6000–6500 s is found for the first time in the soft X-ray emission (0.2–0.6 keV) from T CrB. We associate this periodic variability with the rotational period of the white dwarf in this symbiotic binary.
Physical modelling of galaxy cluster Sunyaev–Zel’dovich data using Einasto dark matter profiles
Authors: Javid Kamran , Perrott Yvette C , Rumsey Clare , Saunders Richard D E
Published: August 2019

We derive a model for Sunyaev–Zel’dovich data from a galaxy cluster that uses an Einasto profile to model the cluster’s dark matter component. This model is similar to the physical models for clusters previously used by the Arcminute Microkelvin Imager (AMI) consortium, which model the dark matter using a Navarro–Frenk–White (NFW) profile, but the Einasto profile provides an extra degree of freedom. We thus present a comparison between two physical models which differ only in the way they model dark matter: one which uses an NFW profile (PM I) and one that uses an Einasto profile (PM II). We illustrate the differences between the models by plotting physical properties of clusters as a function of cluster radius. We generate AMI simulations of clusters that are created and analysed with both models. From this we find that for 14 of the 16 simulations, the Bayesian evidence gives no preference to either of the models according to the Jeffreys scale, and for the other two simulations, weak preference in favour of the correct model. However, for the mass estimates obtained from the analyses, the values were within 1σ of the input values for 14 out of 16 of the clusters when using the correct model, but only in 6 out of 16 cases when the incorrect model was used to analyse the data. Finally, we apply the models to real data from cluster A611 obtained with AMI, and find the mass estimates to be consistent with one another except in the case of when PM II is applied using an extreme value for the Einasto shape parameter.
The multiplicity distribution of Kepler’s exoplanets
Authors: Sandford Emily , Kipping David , Collins Michael
Published: August 2019

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

The 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

The 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

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

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

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

"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

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

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

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

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

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

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

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

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

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

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

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

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.
Estimating Tree Diameter and Volume with a Taper Model and Large-Scale Photo Measurements
Authors: Hall R.J. , Wang Y. , Morgan D.J.
Published: August 2019

Large-scale photo (LSP) mensurational procedures were developed, in part, to reduce field costs by replacing much of the ground sampling with less expensive photo measurements. The conventional LSP approach uses photo measurements of tree height and crown area, which serve as independent variables in models, to predict tree diameter or volume. This study compared 18 linear and nonlinear model forms for estimating tree diameters and assessed the use of a provincial taper model to estimate total tree volume from LSP data. On average, linear models produce R2, root mean square error, and mean bias values that were at least equivalent to, if not statistically better than, nonlinear models for the range of data evaluated. For lodgepole pine, white spruce and a composite of two deciduous species (trembling aspen and balsam poplar), total volume estimates were not statistically different from those estimated from field measurements. A comparative analysis of LSP and field sampling costs suggests the use of taper models in LSP mensuration could save considerable cost and effort in data collection and model development. This finding may result in an increased use of LSP in operational forest inventory work. North J. Appl. For. 18(4):110–118.
Comparison of Field Methods and Models to Estimate Mean Crown Diameter
Authors: Bechtold William A. , Mielke Manfred E. , Zarnoch Stanley J.
Published: August 2019

The direct measurement of crown diameters with logger's tapes adds significantly to the cost of extensive forest inventories. We undertook a study of 100 trees to compare this measurement method to four alternatives—two field instruments, ocular estimates, and regression models. Using the taping method as the standard of comparison, accuracy of the tested alternatives was adequate for softwood species, but short of the specified measurement quality objective for estimating the mean crown diameter of hardwoods. Due to savings in field costs, ocular estimation and regression models were the best alternatives to direct measurement with logger's tapes.
New Approaches to Uneven-Age Management in New England
Authors: Leak William B. , Gottsacker James H.
Published: August 2019

Because of greater emphasis on nontimber values in New England, uneven-age management is drawing more interest among the larger ownerships. Uneven-age management approaches recommended in the past were both costly and biologically undesirable. However, recent findings are enabling the development of more feasible uneven-age guidelines for regenerating valuable species, conducting practical cutting operations, controlling marking, and keeping records. North J. Appl. For. 2:28-31, March 1985.
A Stocking Guide for European Larch in Eastern North America
Authors: Gilmore Daniel W. , Briggs Russell D.
Published: August 2019

European larch is a fast-growing exotic species that shows promise in alleviating projected fiber supply shortages with numerous plantations being established in the Lake States, the Northeast, and Canada during the last two decades. Prescribing thinning regimes for these plantations would be facilitated through the use of a stocking chart. Few older plantations exist in North America, however, thus fitting equations to construct an A-line that requires data from a large number of stands is not possible. We introduce a new approach to constructing an A-line by using the stand density index that in essence is a modification of the traditional tree area ratio approach. We then invoke the self-thinning rule to produce a reference line for Maximum Average Density and an equation for open-grown trees to produce a reference line for Full Site Occupancy in the construction a stocking chart for field use. We also provide yield estimates by diameter class at maximum and minimum stocking levels. North. J. Appl. For. 20(1):34–38.
Natural Resource Professional Continuing Education Needs in Minnesota: Focus on Forest Management Guidelines
Authors: Eliason Sara K. , Blinn Charles R. , Perry James A.
Published: August 2019

Approaches to forest management are changing as the public's expectations for forest resources broaden, environmental concern grows, and scientific knowledge about forests advances. Natural resource professionals rely in part on continuing education to stay abreast of new ideas and strategies for managing forest resources. In Minnesota, new voluntary timber harvesting and forest management guidelines are changing forestry, and continuing education is a vital strategy for encouraging use and demonstrating the application of these nonregulatory guides. To ensure that such educational programs are successful, a series of focus groups was conducted to learn about natural resource professionals' education needs with regard to the voluntary timber harvesting and forest management guidelines. This needs assessment reveals that natural resource professionals want to become familiar with the rationale and background behind the guidelines, learn how to work with the flexibility built into the guidelines, and practice making decisions about which guidelines to use in various situations. Natural resource professionals prefer outdoor workshops with loggers that allow for interaction among participants. We present recommendations for conducting forest management guideline education programs; these recommendations also apply generally to education programs for other natural resource professionals. North. J. Appl. For. 20(2):71–78.