bluuebunny/crossref_metadata_2025 huggingface dataset:
A 2D deuterium NMR study of molecular reorientation in (CH3)3E+X- onium salts
Authors: Wachner Andrew M , Jeffrey Kenneth R , Penner Glenn H
Published: April 2011

Two dimensional deuterium NMR measurements are reported for three different onium salts (CH3)3SeNO3-d3, (CH3)3TeI-d3, and (CH3)3SI-d9. In these molecular solids with the general structure (CH3)3E+X-, three methyl groups are attached to the E atom. There is the possibility of reorientation of the methyls about their C3 axes and reorientation of the whole tri-methyl group about the C'3 axis. From an analysis of the 2D NMR exchange spectra the angle between the E-C bonds and the rotation axis for trimethyl reorientation were determined. Exchange rates and spin lattice relaxation times are given for several temperatures, to show how the mixing times for the experiments were selected. The data presented for (CH3)3TeI-d3, demonstrate that 2D techniques are sensitive to motions on a time scale an order of magnitude slower than that accessible using 1D line shape techniques.Key words: deuterium NMR, molecular motion, onium salts, two dimensional spectra.
Infrared titration of aqueous NaOH by aqueous HCl
Authors: Max Jean-Joseph , Chapados Camille
Published: April 2011

The titration of NaOH by HCl is achieved through infrared spectral measurement of the various mixtures. Factor Analysis (FA) is used to separate the spectra. Four principal spectra were necessary to perform the analysis: pure water, 2.09 M HCl, 2.23 M NaOH, and 2.60 M NaCl solvated water. Each of the 18 experimental spectra obtained was determined to be a linear combination of these principal spectra. The composition of the solutions retrieved from the IR analysis is identical to what was determined by the mass balance. The mean activity coefficient of HCl was calculated using the concentration of HCl obtained by IR and the activity obtained by pH measurements. It was found that the mean activity coefficient increased by a factor greater than 2 in the presence of 1 M NaCl. Because the water molecules associated to the ionic pair H+/Cl-, as observed by IR, are unmodified by the presence of the salt, such an increase cannot be attributed to a modification of the strong association of the water molecules to the pair of ions.Key words: infrared spectroscopy; ATR; liquid; acidic solutions; alkaline solutions; aqueous solutions; factor analysis; principal spectra; HCl-, NaOH-, NaCl-solvated water; activity coefficient; IR titration.
Stereoselective synthesis of renin inhibitor BILA 2157 BS
Authors: Simoneau Bruno , Lavallée Pierre , Bailey Murray , Duceppe Jean-Simon , Grand-Maître Chantal , Grenier Louis , Ogilvie William W , Poupart Marc-André , Thavonekham Bounkham
Published: April 2011

We have developed a convergent and stereoselective synthesis of orally active renin inhibitor BILA 2157 BS. Three building blocks were used to generate the basic skeleton of the inhibitor. The key feature consisted of the late elaboration of the 2-amino-4-thiazolyl heterocycle from a vinylbromide precursor. The synthetic sequence, which required a total of 22 chemical steps, provided 0.6 kg of BILA 2157 BS in 7.3% overall yield.Key words: renin, inhibitor, peptidomimetic, stereoselective synthesis.
Delineating the possibilities for intramolecular interception of the squarate ester cascade through the use of metalated enecarbamates
Authors: Tae Jinsung , Paquette Leo A
Published: April 2011

Highly functionalized and annulated 2,4-cyclooctadienones are formed in a stereoselective manner by sequential treatment of squarate esters with a lithiated enecarbamate (six-membered ring or larger) and a cycloalkenyl- or 1-alkenyllithium reagent. The mechanistic details of this multistep process are presented. Particular attention is drawn to the step that involves intramolecular nucleophilic attack by a proximal oxido anion at the carbamate carbonyl and results in redirection of the cascade. This step is thwarted when five-membered cyclic enecarbamates are employed because of the excessive buildup of ring strain in the associated transition state.Key words: squarate esters, enecarbamates, conrotatory ring opening, intramolecular acylation, alkenyllithium reagents.
Theoretical studies of azulene and its derivatives
Authors: Wang Bo-Cheng , Lin Yun-Shan , Chang Jian-Chuang , Wang Pei-Yu
Published: April 2011

The results of ab initio calculations with the 6-31G basis sets on azulene and its derivatives (including azulenequinones and diazoazulenequinones) are presented in accordance with considerations of their structures and bonding. Azulene is a non-alternant compound with ten π electrons and has either a Cs or C2v symmetry depending on the different carbon bonding. The semiempirical and HF ab initio calculations converge to a Cs symmetry and the DFT and MP2 calculations converge to a C2v symmetry as a ground state structure of azulene. The CIS calculations describe the excited state of azulene and the first excitation energy (S0 - S1) is 533 nm (CIS/6-31+G*), which could illustrate the azure color of azulene. According to the geometry analysis, there are 16 geometrical isomers in azulenequinone conjugated diketones of azulene. Ab initio calculation with the 6-31G basis set generates 1,5- and 1,7-azulenequinone being the most stable isomers of azulenequinone. Theoretically, the relative stability of the bromination product of azulenequinones indicates that 7-bromo-1,5-azulenequinone and 3-bromo-1,7- azulenequinone (for monobromoazulenequinones) and 3,7-dibromo-1,5- azulenequinone and 3,5-dibromo-1,7-azulenequinone (for dibromoazulenequinones) are more stable isomers. The product of diazotization of amino- bromoazulenes is diazoazulenequinone in which a diazo group replaces a ketone group. Isomeric 1,8- and 1,2-diazoazulenequinones are the most stable isomers of diazoazulenequinone according to the theoretical consideration. Due to the resonance and relative stability, diazoazulenequinone may easily extrude nitrogen and form the corresponding triplet ketocarbene intermediate and electronic isomers that undergo photoreaction with THF leading to a polyether bridged azulene (crown type ether). The cyclic reactions in diazoazulenequinone are also studied.Key words: azulene, azulenequinone, diazoazulenequinone, ab initio.
A review of the occurrence, toxicity,and biodegradation of condensed thiophenes found in petroleum
Authors: Kropp Kevin G , Fedorak Phillip M
Published: April 2011

Condensed thiophenes comprise a significant portion of the organosulfur compounds in petroleum and in other products from fossil fuels. Dibenzothiophene (DBT) has served as a model compound in biodegradation studies for over two decades. However, until quite recently, few other organosulfur compounds were studied, and their fates in petroleum-contaminated environments are largely unknown. This paper presents a review of the types of organosulfur compounds found in petroleum and summarizes the scant literature on toxicity studies with condensed thiophenes. Reports on the biodegradation of benzothiophene, alkylbenzothiophenes, DBT, alkylDBTs, and naphthothiophenes are reviewed with a focus on the identification of metabolites detected in laboratory cultures. In addition, recent reports on quantitative studies with DBT and naphtho[2,1-b]thiophene indicate the existence of polar sulfur-containing metabolites that have escaped detection and identification. Key words: biodegradation, condensed thiophenes, dibenzothiophene, microbial metabolism, toxicity.
Using spontaneous antibiotic-resistant mutants to assess competitiveness of bradyrhizobial inoculants for nodulation of soybean
Authors: Ramirez Martha E , Israel Daniel W , Wollum II Arthur G
Published: April 2011

Spontaneous mutants (3/parental strain) of soybean bradyrhizobia resistant to streptomycin and erythromycin were selected from strains isolated from bradyrhizobial populations indigenous to Cape Fear and Dothan soils. These were used to evaluate (i) the validity of using antibiotic-resistant mutants to make inferences about the competitiveness of parental strains in soil environments and (ii) the recovery of strains in nodules after inoculation of soybeans grown in soils with indigenous bradyrhizobial populations. Streptomycin and erythromycin resistances of all mutants were stable after approximately 27 generations of growth in yeast extract - mannitol medium, but 33% of the mutants lost resistance to erythromycin upon passage through nodules. Only 17% of the mutants were as competitive as their parental strain when inoculated in a ratio near 1:1 in vermiculite. Four of 10 mutants, which differed in competitiveness from their parental strain in vermiculite, had competitiveness against the soil populations equal to that of their parental strain. Therefore, assessment of competitiveness of mutants and parental strains in non-soil media may not accurately reflect their competitiveness in soil systems. For both the Cape Fear and Dothan soils, recovery of a given mutant from nodules of field-grown plants was always lower than from nodules of plants grown in the greenhouse. Inoculation of the entire rooting zone in the greenhouse experiment and of only a portion of the rooting zone in the field experiments may account for this difference in recovery. Techniques that increase the volume of soil inoculated may enhance nodulation by inoculant strains.Key words: Bradyrizobium, antibiotic resistance, competition.
Use of almond mesocarp for production of the entomopathogenic fungus Verticillium lecanii
Authors: Lopez-Llorca L V , Carbonell T
Published: April 2011

Almond mesocarp (AM) has been evaluated for production of Verticillium lecanii. Microbial flora of AM has been studied. After ground AM dilution plating, 5.3 × 105 ± 2.6 × 104 fungal CFU·g-1 of dry AM were found. Common fungal saprophytes (Rhizopus sp. and Alternaria spp.) were found in more than 80% of the samples. Aspergillus sp. and yeasts were found less commonly. Rhizopus sp., Alternaria spp., and Aspergillus sp. inhibited growth of several V. lecanii; therefore, AM was treated with sterilization agents to eliminate endogenous mycoflora. Small samples (10 g) of AM saturated in distilled water treated with steam (120°C and 100 kPa) were completely sterilized after 15 min. Ground AM incorporated on agar increased the biomass of V. lecanii compared with controls. This suggested AM as suitable substrate for the production of the fungus. In petri dishes, 9.7 × 107 ± 2.9 × 107 conidia·g-1 of dry AM were produced after inoculating 10 conidia·g-1of AM and incubating for 2 weeks. Viability of conidia produced was more than 90%. These conidia (5 × 104 conidia per larvae) caused Galleria mellonella mortality, calculated as median lethal time (LT50 5.3 ± 1.6 days), that was significantly higher (F = 10.93; P < 0.05) than untreated controls (LT50 11.3 ± 1.1 days). Larger scale tests have to be optimized before mass production.Key words: Verticillium lecanii, almond mesocarp, production, entomopathogenic fungi, bioassays.
Effect of aromatic compounds on growth and ligninolytic enzyme production of two white rot fungi Ceriporiopsis subvermispora and Cyathus stercoreus
Authors: Sethuraman Anand , Akin Danny E , Eisele Jason G , Eriksson Karl-Erik L
Published: April 2011

Seven benzoic acid, ten cinnamic acid, and five benzaldehyde derivatives were tested for their effects on hyphal growth and production of laccase and manganese peroxidase by Ceriporiopsis subvermispora FP 90031-sp and Cyathus stercoreus ATCC 36910. Derivatives tested included phenolic compounds and their corresponding unsubstituted and O-methylated derivatives. Benzaldehyde derivatives were more toxic to both fungi than the corresponding benzoic and cinnamic acid derivatives. Hyphal growth was generally increased at a low concentration of 1 mM, while higher concentrations of 5-10 mM mostly resulted in less or no growth. Hyphal growth and enzyme production response were compound specific. However, generally monomethoxylated compounds were more toxic than compounds with an additional methoxyl group. Cyathus stercoreus was more sensitive than Ceriporiopsis subvermispora to most of the compounds tested and thus showed poorer growth. Cyathus stercoreus produced higher concentrations of manganese peroxidase than Ceriporiopsis subvermispora for all the compounds tested, whereas laccase activity was higher in Ceriporiopsis subvermispora for most of the compounds tested. Di- and tri-methoxylated compounds induced more laccase and manganese peroxidase activities than the corresponding hydroxylated derivatives. At 1 mM levels, 3,4-dimethoxycinnamic acid induced the greatest increase in laccase production for Ceriporiopsis subvermispora and Cyathus stercoreus (245 and 290% of control, respectively). Syringic acid induced manganese peroxidase (MnP) to 536% of that in control for Ceriporiopsis subvermispora, and both 3,4-dimethoxycinnamic acid and 3,4,5-trimethoxycinnamic acid induced MnP to over 300% of control for Cyathus stercoreus. The results provide a body of information on the effects of specific aromatic compounds on two potentially industrially important fungi. Key words: biomass conversion, aromatic compounds, white rot fungi, fungal growth, enzyme production.
General (Biolog GN) versus site-relevant (pollutant-dependent) sole-carbon-source utilization patterns as a means to approaching community functioning
Authors: Becker Petra M , Stottmeister Ulrich
Published: April 2011

Biolog community-level sole-carbon-source utilization patterns are widely applied to distinguish between the microbiota of different habitats or reveal disturbances in microbial ecosystems. Our objective was to examine whether the metabolic diversity measured in the Biolog system could be related to community functioning, thus providing more information than being merely discriminative for communities. To answer this question, we compared the percentages of specific pollutant utilizers with the percentages of the degraders of distinct general (Biolog) substrates in arbitrary samples of isolates, employing in both cases the isolate sample assay (ISA). Samples for arbitrarily selected isolates were taken from in situ enclosures situated in the anaerobic lignite-carbonization effluent Lake Schwelvollert (district of Weißenfels, Saxony-Anhalt, Germany). A different aerobic-carbonization wastewater treatment was carried out in each of the in situ enclosures. It was shown that distinct arbitrarily compiled isolate samples, which displayed similar functional patterns in terms of the degradation of pollutant-related compounds, exhibited significantly different general metabolic capacities as measured using Biolog kits. The similar pollutant-degradation potentials of the arbitrary isolates indicated that the site's substrate supply plays an important role in deciding which bacteria can become indigenous, seemingly leaving room for the otherwise varying properties of the individual community members.Key words: lignite-carbonization wastewater, ISA (isolate sample assay), sole-carbon-source utilization, Biolog, community functioning.
Characterization of an endo-1,3-β-D-glucanase produced during the interaction between the mycoparasite Stachybotrys elegans and its host Rhizoctonia solani
Authors: Archambault Christian , Coloccia Giuseppina , Kermasha Selim , Jabaji-Hare Suha
Published: April 2011

The mycoparasite Stachybotrys elegans produces, in addition to a previously purified 94-kDa 1,3-β- glucanase, at least three extracellular 1,3-β-glucanases (75, 110, and 180 kDa) when grown on purified cell wall of Rhizoctonia solani. We purified to homogeneity an endo-1,3-β-glucanase of 75 kDa which possesses a low Km value of 20 μg laminarin·mL-1 and is most active at pH 5.0 and 40°C. Polyclonal antibodies raised against both the 75- and 94-kDa 1,3-β-glucanases indicate that they are immunologically related but do not cross-react with the 110- and 180-kDa glucanases. Exposure of growing hyphal tips of R. solani to the pure 75-kDa 1,3-β-glucanase caused them to swell and lyse. A transient increase of the 75-kDa 1,3-β-glucanase with a concomitant decrease of the 94-kDa 1,3-β-glucanase and the appearance of a 20-kDa protein were observed at the point of interaction between R. solani and Stachybotrys elegans on plates. Evidence suggesting a precursor-product relationship between the two 1,3-β-glucanases is provided. Our results indicate that the 75-kDa 1,3-β-glucanase may be involved in Stachybotrys elegans mycoparasitism.Key words: cell wall hydrolytic enzyme, glucanase, mycoparasite, Rhizoctonia solani, Stachybotrys elegans.
A novel method for hybridization of Saccharomyces species without genetic markers
Authors: Kucsera Judit , Pfeiffer Ilona , Ferenczy Lajos
Published: April 2011

Protoplasts of Saccharomyces cerevisiae were inactivated by treatment with different concentrations of antifungal compounds for various periods. Of the 14 compounds tested, N-ethylmaleimide proved to be the most efficient. The inactivation effect was fully reproducible. The inactivated protoplasts could be reactivated and still function as fusion partners. They were fused with untreated protoplasts by polyethylene glycol treatment and produced viable hybrid cells. Nuclear and extrachromosomal genetic analysis and chromosome separation of the fusion products from fusion experiments involving inactivated and non-inactivated protoplasts revealed that N-ethylmaleimide did not affect either of the genomes and hence it was perfectly suited for the hybridization of any type yeast cells without genetic markers.Key words: yeast protoplast fusion, chemical inactivation, chromosomal polymorphism, interspecies hybrid.
Production of species-specific monoclonal antibodies that react with surface components on zoospores and cysts of Phytophthora nicotianae
Authors: Robold A V , Hardham A R
Published: April 2011

Monoclonal antibodies were generated against components on the surface of zoospores and cysts of the Oomycete, Phytophthora nicotianae, with the aim of obtaining antibodies diagnostic for this species of plant pathogen. A dipstick version of an enzyme-linked immunosorbent assay was used to screen hybridoma cell lines produced by following a coimmunization protocol in which a mouse was immunized with Phytophthora nicotianae cysts mixed with murine antisera raised against cysts of Phytophthora cinnamomi and Phytophthora cryptogea. Of the nine hybridoma cells lines which remained positive, five produced antibodies that reacted with species-specific epitopes on the surface of the spores. Immunofluorescence, immunogold, and immunoblot labelling showed that three of the five species-specific antibodies reacted with a polypeptide of relative molecular mass greater than 205 kDa which was distributed over the entire zoospore surface, including that of the two flagella. These antibodies also labelled the surface of cysts to varying degrees. The other two species-specific antibodies bound to the shaft of tubular mastigonemes that form two rows on the anterior flagellum. In immunoblots, one of these antibodies recognised a 40-kDa glycoprotein. Antibodies produced by the other four hybridoma cell lines reacted with all Phytophthora and Pythium species tested. The results (i) showed that the coimmunization technique effectively produced antibodies directed towards components specific for Phytophthora nicotianae in the presence of antigens common to many Phytophthora species, and (ii) revealed for the first time the biochemical nature of molecular constituents of flagellar mastigonemes in the Oomycetes.Key words: cell surface, flagella, immunodiagnostics, mastigonemes, monoclonal antibodies.
Organic solvent-tolerant mutants of Pseudomonas aeruginosa display multiple antibiotic resistance
Authors: Li Xian-Zhi , Poole Keith
Published: April 2011

Organic solvent-tolerant mutants of Pseudomonas aeruginosa selected in the presence of hexane exhibited increased resistance to a variety of structurally unrelated antimicrobial agents, including beta-lactams, fluoroquinolones, chloramphenicol, tetracycline, and novobiocin, a phenotype typical of nalB multidrug-resistant mutants. Western immunoblotting with antibodies specific to components of the three known multidrug efflux systems in P. aeruginosa demonstrated that the solvent-tolerant mutants displayed increased expression of the MexAB-OprM system and decreased expression of the MexEF-OprN system. Sequence analysis of mexR, the repressor gene of mexAB-oprM efflux operon, identified a nonsense mutation and a point mutation in the mexR genes of two solvent-tolerant mutants. These results emphasize the importance of the MexAB-OprM efflux system in organic solvent tolerance and the ability of environmental pollutants to select bacteria with a medically relevant antibiotic-resistant phenotype.Key words: Pseudomonas aeruginosa, organic solvent tolerance, multidrug resistance, MexAB-OprM efflux pump, mexR gene.
Biophysical and potential vegetation growth surfaces for a small watershed in northern Cape Breton Island, Nova Scotia, Canada
Authors: Bourque Charles P-A , Meng Fan-Rui , Gullison Jeremy J , Bridgland James
Published: April 2011

Surfaces of potential vegetation growth in this paper represent the spatial distribution of growing conditions (habitat) for six deciduous tree species native to the Clyburn River valley watershed of northeastern Cape Breton Island, Nova Scotia. Development of potential growth surfaces is based on integrating point calculations of (i) net potential solar radiation, (ii) net long-wave radiation, (iii) growing season degree-day accumulation, and (iv) mean summer soil water content with species-specific evaluations of long-term species environmental response. Functions describing potential species response to available environmental resources are based on generalised mathematical functions that scale species response values between 0 and 1, where 0 represents unsuitable growing conditions and 1, optimal growing conditions. Limitation effects of resource deficits on potential growth are addressed as a multiplication of individual environmental responses. Derived species distributions of potential growth are compared with aerial photo-interpreted distributions of forest vegetation found within the Clyburn River valley watershed. Modelled and photo-interpreted valley distributions demonstrate nearly similar geographic ranges. Actual percent cover for shade-tolerant species displays a positive correlation with modelled potential growth (r2 = 0.5). This is not the case for shade-intolerant species considered, whereby r2 [Formula: see text] 0.
Decomposition of broadleaf and needle litter in forests of British Columbia: influences of litter type, forest type, and litter mixtures
Authors: Prescott C E , Zabek L M , Staley C L , Kabzems R
Published: April 2011

We measured rates of decomposition at three sites representing the major mixedwood forest types of British Columbia: (i) boreal forests of white spruce (Picea glauca (Moench) Voss) and trembling aspen (Populus tremuloides Michx.); (ii) coastal forests of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and red alder (Alnus rubra Bong.); and (iii) a wet interior forest of Douglas-fir, paper birch (Betula papyrifera Marsh.), and lodgepole pine (Pinus contorta Doug. ex Loud.). Mass loss of litter of each species (both pure and in combination with the other species) was measured for 2-5 years in forests of each species to determine (i) if broadleaf litter decomposed faster than needle litter, (ii) if litter decomposed faster in broadleaf or mixedwood forests than in coniferous forests, and (iii) if mixing with broadleaf hastened decomposition of needle litter. The broadleaf litters decomposed faster than needles during the first year but, thereafter, decomposed more slowly, so differences were small after 3 years. Litter tended to decompose faster in the broadleaf forests than in the coniferous forests. There was either no effect or a slight suppression of decomposition when litters were mixed; thus, there was no evidence that addition of broadleaf litter hastened decomposition of needle litter. The results clearly indicate that the mixing of needle litter with broadleaf litter is unlikely to hasten decomposition in mixedwood forests of British Columbia. The main influence of broadleaves was more rapid decomposition in broadleaf or mixedwood forest floors, which does not appear to be simply an effect of litter quality or litter mixing.
Survival and growth of Pinus echinata and Quercus seedlings in response to simulated summer and winter prescribed burns
Authors: Cain Michael D , Shelton Michael G
Published: April 2011

First-year seedlings of shortleaf pine (Pinus echinata Mill.), southern red oak (Quercus falcata Michx.), and white oak (Quercus alba L.) were subjected to simulated prescribed burns during August (growing season) or January (dormant season) on an Upper Coastal Plain site in southeastern Arkansas, U.S.A. Survival and growth of resprouting rootstocks were compared with control seedlings through one growing season after burning. Although 100% of the oaks and 99% of the pines were topkilled by the fires, survival of resprouting rootstocks exceeded 95% for all three species in the year following the winter burn. No pines resprouted following the summer burn, but rootstock survival of oaks averaged >65%. Compared with controls, winter burns reduced (P < 0.01) mean height and groundline diameter (GLD) of shortleaf pine sprouts through the next growing season. For southern red oak, season of burning did not negatively affect (P > 0.05) the growth of sprouts during the year after burning. Although mean heights and GLDs of white oak sprouts versus controls were reduced (P [Formula: see text] 0.04) when means were averaged across burns, white oak sprouts on winter-burn plots were comparable in size with the control seedlings.
Ecosystem modeling of methane and carbon dioxide fluxes for boreal forest sites
Authors: Potter Christopher , Bubier Jill , Crill Patrick , Lafleur Peter
Published: April 2011

Predicted daily fluxes from an ecosystem model for water, carbon dioxide, and methane were compared with 1994 and 1996 Boreal EcosystemAtmosphere Study (BOREAS) field measurements at sites dominated by old black spruce (Picea mariana (Mill.) BSP) (OBS) and boreal fen vegetation near Thompson, Man. Model settings for simulating daily changes in water table depth (WTD) for both sites were designed to match observed water levels, including predictions for two microtopographic positions (hollow and hummock) within the fen study area. Water run-on to the soil profile from neighboring microtopographic units was calibrated on the basis of daily snowmelt and rainfall inputs to reproduce BOREAS site measurements for timing and magnitude of maximum daily WTD for the growing season. Model predictions for daily evapotranspiration rates closely track measured fluxes for stand water loss in patterns consistent with strong controls over latent heat fluxes by soil temperature during nongrowing season months and by variability in relative humidity and air temperature during the growing season. Predicted annual net primary production (NPP) for the OBS site was 158 g C·m2 during 1994 and 135 g C·m2 during 1996, with contributions of 75% from overstory canopy production and 25% from ground cover production. Annual NPP for the wetter fen site was 250 g C·m2 during 1994 and 270 g C·m2 during 1996. Predicted seasonal patterns for soil CO2 fluxes and net ecosystem production of carbon both match daily average estimates at the two sites. Model results for methane flux, which also closely match average measured flux levels of 0.5 mg CH4·m2·day1 for OBS and 2.8 mg CH4·m2·day1 for fen sites, suggest that spruce areas are net annual sinks of about 0.12 g CH4·m2, whereas fen areas generate net annual emissions on the order of 0.30.85 g CH4·m2, depending mainly on seasonal WTD and microtopographic position. Fen hollow areas are predicted to emit almost three times more methane during a given year than fen hummock areas. The validated model is structured for extrapolation to regional simulations of interannual trace gas fluxes over the entire North America boreal forest, with integration of satellite data to characterize properties of the land surface.
An alternative to clear-cutting in the boreal forest of Alaska: a 27-year study of regeneration after shelterwood harvesting
Authors: Wurtz T L , Zasada J C
Published: April 2011

We present 27-year results from a comparison of clear-cutting and shelterwood harvesting in the boreal forest of Alaska. Three patch clear-cut and three shelterwood units were harvested in 1972; about 100 dispersed white spruce (Picea glauca (Moench) Voss) leave trees per hectare were retained in the shelterwoods. Units were mechanically scarified and an exceptionally large seed-crop was dispersed that year. Shelterwood trees were removed after 15 years. After 27 years, overstory treatment had no effect on the density or growth of the species we studied, while scarification had highly significant effects. In 1999, scarified areas were densely populated with white spruce seedlings and saplings (118 000  129 000 stems/ha, with spruce in 100% of plots). Unscarified areas had far fewer spruce stems but were nevertheless well stocked (11 000  15 000 stems/ha, with 87% frequency). Initially, spruce grew best on scarified surfaces, but by 27 years, growth of the tallest spruce saplings was significantly greater on unscarified than scarified surfaces. By 27 years, cover of the grass Calamagrostis canadensis (Michx.) Nutt. had returned to preharvest levels in all treatment types. Because criteria for evaluating forest management practices have changed since this study was begun, partial overstory retention systems for the management of Alaska's boreal forest deserve further study.
Susceptibility of parent and interspecific F1 hybrid pine trees to tip moth damage in a coastal North Carolina planting
Authors: Highsmith Maxine T , Frampton John , O'Malley David , Richmond James , Webb Martesa
Published: April 2011

Tip moth damage among families of parent pine species and their interspecific F1 hybrids was quantitatively assessed in a coastal planting in North Carolina. Three slash pine (Pinus elliotti var. elliotti Engelm.), two loblolly pine (Pinus taeda L.), and four interspecific F1 hybrid pine families were used. The F1 hybrids were as susceptible to damage by Nantucket pine tip moth (Rhyacionia frustrana (Comst.)), as was their susceptible loblolly pine parent. Their phenotypes support a dominant or partially dominant mode of inheritance for susceptibility. The phenotype of one slash pine family was not statistically different from the phenotypes of the loblolly and F1 hybrid pines. The high susceptibility of that one slash pine family appeared to be intrinsic, even though slash pine is considered resistant to tip moth damage. Tip moth damage on the two other slash pine families was significantly lower.
Soil respiration and photosynthetic uptake of carbon dioxide by ground-cover plants in four ages of jack pine forest
Authors: Striegl Robert G , Wickland Kimberly P
Published: April 2011

Soil carbon dioxide (CO2) emission (soil respiration), net CO2 exchange after photosynthetic uptake by ground-cover plants, and soil CO2 concentration versus depth below land surface were measured at four ages of jack pine (Pinus banksiana Lamb.) forest in central Saskatchewan. Soil respiration was smallest at a clear-cut site, largest in an 8-year-old stand, and decreased with stand age in 20-year-old and mature (6075 years old) stands during May September 1994 (12.1, 34.6, 31.5, and 24.9 mol C·m2, respectively). Simulations of soil respiration at each stand based on continuously recorded soil temperature were within one standard deviation of measured flux for 48 of 52 measurement periods, but were 10%30% less than linear interpolations of measured flux for the season. This was probably due to decreased soil respiration at night modeled by the temperature-flux relationships, but not documented by daytime chamber measurements. CO2 uptake by ground-cover plants ranged from 0 at the clear-cut site to 29, 25, and 9% of total growing season soil respiration at the 8-year, 20-year, and mature stands. CO2 concentrations were as great as 7150 ppmv in the upper 1 m of unsaturated zone and were proportional to measured soil respiration.
Using witness trees to assess forest change in southeastern Ohio
Authors: Dyer James M
Published: April 2011

In 1787, the U.S. Congress authorized the sale of the "Ohio Company Purchase", ca. 5000 km2 in Appalachian Ohio. The land was surveyed using a township and range system shortly thereafter. Data on >5600 witness trees were transcribed from the survey records, and witness tree locations were plotted on a digital map. This information was used to evaluate presettlement forest composition and structure and to investigate vegetation-site relationships before widespread alteration of the forests had taken place. Presettlement conditions were compared with present conditions using forest inventory and analysis (FIA) data. Two hundred years ago, the forests of southeastern Ohio were dominated by large individuals of Quercus alba L., Carya Nutt. spp., Quercus velutina Lam., and Fagus grandifolia Ehrh. These four taxa accounted for 74% of all witness trees. Although almost 70% of the region is forested today, the second-growth forest has witnessed a decrease in Quercus and Carya and an increase in Acer saccharum Marsh., Acer rubrum L., and many early successional species in smaller size classes. Despite the significant shift in forest composition and structure, species in general seem to be occupying similar positions in the present-day landscape compared with the presettlement forest; topographic variables most strongly control species occurrence in this landscape.
Highly polymorphic microsatellite markers in Chamaecyparis obtusa
Authors: Nakao Y , Iwata H , Matsumoto A , Tsumura Y , Tomaru N
Published: April 2011

Nine microsatellite loci in hinoki, Chamaecyparis obtusa (Sieb. et Zucc.) Endl., were identified and characterized. A genomic library, developed using enrichment with magnetic beads, was screened to identify microsatellite repeats (CT/AG). The microsatellite loci, where the alleles were segregated, displayed codominant Mendelian inheritance. Genetic analysis of 16 plus trees and two unrelated individuals of Chamaecyparis obtusa revealed that all loci were highly polymorphic, with an average of 10.3 alleles per locus, and an average gene diversity of 0.77. The applicability of these microsatellite loci was also tested in other species of the Cupressaceae and in Cryptomeria japonica (L.f.) D. Don (Taxodiaceae, a family closely related to Cupressaceae). Polymerase chain reaction (PCR) amplification was successful for about half of the loci of the species in the genus Chamaecyparis. However, the PCR amplification patterns of the 11 species of Cupressaceae showed no clear correlations with their molecular phylogeny. The highly polymorphic microsatellite loci in Chamaecyparis obtusa, identified here, will be useful in studies of hinoki breeding and population genetics.
Light-growth responses of coastal Douglas-fir and western redcedar saplings under different regimes of soil moisture and nutrients
Authors: Drever C Ronnie , Lertzman Kenneth P
Published: April 2011

We characterized the radial and height growth response to light for coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) and western redcedar (Thuja plicata Donn ex D. Don) saplings growing in sites of different regimes of soil moisture and nutrients on the east coast of Vancouver Island, British Columbia. We determined that at low light levels, site quality has little effect on the growth response of Douglas-fir saplings. At light levels above approximately 40 and 60% full sun, Douglas-fir saplings show statistically significant differences in height and radial growth, respectively, that reflect the differences in soil moisture and nutrient regimes of the sites we examined. Western redcedar approaches its maximum radial and height growth rates at about 30% full sun. Our data suggest that partial-cutting treatments need to create light environments greater than about 40% full sun to achieve growth that represents a high proportion of the site growing potential for Douglas-fir at full sun, while the high shade tolerance of western redcedar allows silvicultural treatments that retain a high amount of forest structure without compromising growth rates of young trees.
Inexpensive Diode Thermometry Using Integrated Circuit Components
Authors: Tang P. A. , McNaughton K. G. , Black T. A.
Published: April 2011

Two temperature sensing circuits using silicon diodes and integrated circuit components are described. They are intended for use with data acquisition systems and are suitable for field or laboratory applications. Both can be constructed by persons without electronic training and have features of simplicity, low cost, and high accuracy.
Thermal Tolerance of Poriaweirii
Authors: Nelson E. E. , Fay H.
Published: April 2011

Poriaweirii (Murr.) Murr., an important root pathogen in western coniferous forests, may survive for years in buried colonized wood. Temperature, interacting with microflora, influences the longevity. When P. weirii was grown in alder stem sections and incubated relatively free from fungal competition, it survived 32 weeks at temperatures between −5 and 30 °C. Survival was reduced progressively toward either extreme from −20 to +39 °C. Preconditioning of colonized stem sections at low temperatures improved survival at −15 °C. Though extreme hot or cold temperature can be lethal to P. weirii, these temperatures do not occur very deep in soil within the geographic distribution of the pathogen. Temperature is likely only an indirect factor in limiting survival of the fungus in forest soils over its geographic range.
Variation in Polyphenol Content Within and Between Sitka Spruce Provenances at Different Sites
Authors: Forrest G. I.
Published: April 2011

The concentrations and total weights of polyphenol fractions were measured in 2-year-old lateral branches from the upper part of Sitka spruce trees of four provenances growing at four widely separated sites in Britain. Variation between trees within a provenance was high, but there were highly significant differences between provenances and between sites. The highest polyphenol concentrations occurred in the most northerly provenances and at the least favorable sites for growth. The highest total weights of polyphenols occurred at the most favorable site for growth, but there were no significant differences between provenances. Many of the variables measured were highly correlated with each other. The stilbenes and leucoanthocyanins were the most informative groups of compounds, and the leucoanthocyanin content showed a high correlation with vigor. It is concluded that differences in polyphenol content between provenances are confounded by variation due to site and to vigor.
Influence de l'application de superphosphate et de K2SO4•MgSO4 avec l'urée à un humus de forêt de pin gris. I. Uréolyse et volatilisation ammoniacale
Authors: Carrier D. , Bernier B.
Published: April 2011

The hydrolysis of urea added (224 kg N/ha) to jack-pine (Pinusbanksiana Lamb.) raw humus incubated at 20 °C and 80% of field capacity was almost complete after 3 days of incubation; after 35 days, volatile ammonia losses amounted to 21.7% of the applied urea-N. Addition of triple superphosphate (TSP) or potassium–magnesium sulphate (SPM) with urea retarded ureolysis and reduced ammonia volatilization, the effect of TSP on these two processes being more pronounced than that of SPM. When TSP or TSP + SPM were applied 1 week before urea application, ureolysis was further retarded, but this had little additional effect on the reduction of volatile ammonia losses. The effect of TSP or of SPM on ureolysis seems to be partly related to their buffering action but also to the inhibition of soil urease.
Some observations on the shoot growth of pine seedlings
Authors: Thompson S.
Published: April 2011

Sequential observations in lodgepole pine (Pinuscontorta Dougl.) and Scots pine (P. sylvestris L.) showed that the second season's shoot was not produced solely from stem units in the terminal resting bud as previously assumed. The stem units held in the rosette of primary needles surrounding the terminal bud elongated to form most of the second season's shoot. The terminal bud only contributed 29 to 54% of the stem units. There was a marked difference between an inland and a coastal provenance of lodgepole pine in the appearance of the shoot apex at the end of the first growing season.
Effect of mechanical stress on growth and anatomical structure of red pine: stem vibration
Authors: Quirk J. Thomas , Freese Frank
Published: April 2011

Two studies were made of the effects of stem vibration on tree growth and anatomical structure. Vibration was used to simulate wind sway.The results of a greenhouse and an outdoor study were not consistent but did suggest that vibration might cause a short-term reduction in growth. There was no evidence that the level of vibration used caused any change in wood structure.Soil moisture affected anchorage of the tree in the soil. This, in turn, affected lateral displacement resulting from vibration and influenced the redistribution of the new volume growth.
Geographic variation in balsam fir: 11-year results in the Lake States
Authors: Lester D. T. , Mohn C. A. , Wright J. W.
Published: April 2011

Up to 60 balsam fir provenances were evaluated at five locations in the Lake States at an age of 11 years from seed. Provenance effects were statistically significant at each location and, in general, eastern provenances were taller and produced more branches than western ones, while the initiation of shoot elongation followed a latitudinal gradient, with earliest flushing among provenances from north of 49° N. There were large differences, however, between some provenances from the same state or province. Provenance-plantation interaction was present in all tested combinations of plantations, but no geographic pattern of phenotypic instability was found. The observed results may reflect a geographic pattern of high vigor in eastern provenances confounded by effects of spring frost mediated through phenology of shoot elongation. Certain provenances have the desirable combination of vigor and late flushing.
Morphological inheritance in selected Pinusechinata, P. taeda, and putative hybrids
Authors: Bhat Ajaz A. , Hicks Jr. Ray R.
Published: April 2011

Seedlings from loblolly (Pinustaeda L.), shortleaf (P. echinata Mill.), and morphologically intermediate pines (putative hybrids) were grown in greenhouse flats. Hybrid index scores based on morphological traits were calculated for parent trees and open-pollinated progeny. The scores of open-pollinated families were well correlated with those of their respective parents, indicating that parental hybrid index is a relatively accurate indicator of genotype.For several parent trees initially classed as putative hybrids, hybrid index scores tended toward shortleaf pine. Subsequent observations of progeny revealed that, except for one family, progeny were indistinguishable from shortleaf pines. This exception was intermediate to both species for both parent and progeny morphology and was concluded to be a natural hybrid.
Development of peripheral periderm from cork strips in Ceratoniasiliqua
Authors: Arbel Ehud , Arzee Tova
Published: April 2011

The formation of cork in vertical strips on young branches of Ceratoniasiliqua L. is described. The cork strips represent an early stage in the development of peripheral periderm. Initiation of the cork ridges began with the differentiation of lenticels in vertical rows and further development occurred through the subsequent formation of periderm, primarily in the longitudinal direction. A circumfluent covering of periderm was formed eventually by lateral extension of phellogen leading to the gradual coalescence of the cork strips. Similarities with patterns of cork wing development are discussed.
Temperature and pH optima for germination of Arkansas collections of comandra blister rust aeciospores1
Authors: Eppstein Deborah A. , Tainter F. H.
Published: April 2011

The pH optimum for germination of aeciospores of Arkansas collections of Cronartiumcomandrae Pk. was determined to be 6.9. The temperature optimum was determined to be 19–20 °C, which is considerably higher than reported for most Rocky Mountain collections of this fungus.
Optimizing timber sales during the conversion period
Authors: Johnson K. Norman
Published: April 2011

A perennial problem in timber management concerns the rate at which timber should be sold while a forest is converted from an unregulated to a regulated condition. An analysis of this problem was recently undertaken for a private timber company in the western United States. Study of alternative timber flows over the first half of the conversion period revealed that the firm faced a definite trade-off between stability and amount of income. Because the firm faced a downward-sloping demand for its stumpage, immediate liquidation of all available timber, as indicated by classical financial maturity techniques, was not appropriate. Quadratic programming was used to find an income-maximizing harvest rate that recognized this downward-sloping demand.
Rate of increase of blue stained volume in mountain pine beetle killed lodgepole pine in northeastern Oregon, U.S.A.
Authors: Harvey Jr. Robert D.
Published: April 2011

Recently killed lodgepole pine (Pinuscontorta Dougl.) were examined to determine rate of spread of blue stain fungi introduced by mountain pine beetle (Dendroctonusponderosae Hopk.). Trees were felled, dissected at 2.5-m intervals, and photographed at each cross section to determine area of stain. Rate of spread is so rapid that salvaging mountain pine beetle killed lodgepole pine prior to severe staining is difficult.
Aspects of statistical bias due to the forest edge: fixed-area circular plots
Authors: Fowler Gary W. , Arvanitis Loukas G.
Published: April 2011

A procedure is presented to eliminate edge-effect statistical bias for fixed-area circular plots when sampling forest areas. For known forest populations, the exact mean of the unbiased (adjusted for edge effect) and biased (unadjusted for edge effect) estimates of a forest characteristic can be determined along with the exact bias. Edge-effect bias is investigated for three forests that vary in area, four plot sizes, and three forest characteristics. Exact and estimated results based on 5000 random points were compared. Edge-effect bias increases with plot area and varies with forest size, spatial distribution of trees, percentage of edge trees, and forest characteristic. The variance of the biased estimator was always smaller than the variance of the unbiased estimator. Using mean square errors, the biased estimator was found to be more accurate and the distortion of probability statements caused by the bias negligible for moderate sample sizes and small-plot areas.
Estimate of nitrogen fixation on leaf surfaces of forest species in Minnesota and Oregon
Authors: Sucoff Edward
Published: April 2011

Leafy branches from 52 tree or shrub species collected from Minnesota forests during July and August, 1976, and (or) May and September, 1977, were tested for their ability to fix nitrogen. Seven species were similarly sampled in western Oregon during November, 1976. Nitrogen fixation was assessed by the acetylene reduction method. Little, if any, acetylene reduction was detected on branches without epiphytes. The upper limits of possible nitrogen fixation on the leaf surfaces were below amounts important in the nitrogen economy of the stands.