bluuebunny/crossref_metadata_2025 huggingface dataset:
Mucosal Administration of Flagellin Protects Mice from
Streptococcus pneumoniae
Lung Infection
Authors: Muñoz Natalia , Van Maele Laurye , Marqués Juan M. , Rial Analía , Sirard Jean-Claude , Chabalgoity José A.
Published: July 2010

Streptococcus pneumoniae
is a major cause of pneumonia in infants and the elderly. Innate defenses are essential to the control of pneumococcal infections, and deficient responses can trigger disease in susceptible individuals. Here we showed that flagellin can locally activate innate immunity and thereby increase the resistance to acute pneumonia. Flagellin mucosal treatment improved
S. pneumoniae
clearance in the lungs and promoted increased survival of infection. In addition, lung architecture was fully restored after the treatment of infected mice, indicating that flagellin allows the reestablishment of steady-state conditions. Using a flagellin mutant that is unable to signal through Toll-like receptor 5 (TLR5), we established that TLR5 signaling is essential for protection. In the respiratory tract, flagellin induced neutrophil infiltration into airways and upregulated the expression of genes coding for interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), CXCL1, CXCL2, and CCL20. Using depleting antibodies, we demonstrated that neutrophils are major effectors of protection. Further, we found that B- and T-cell-deficient SCID mice clear
S. pneumoniae
challenge to the same extent as immunocompetent animals, suggesting that these cell populations are not required for flagellin-induced protection. In conclusion, this study emphasizes that mucosal stimulation of innate immunity by a TLR not naturally engaged by
S. pneumoniae
can increase the potential to cure pneumococcal pneumonia.
An ABC Transporter and a TonB Ortholog Contribute to
Helicobacter mustelae
Nickel and Cobalt Acquisition
Authors: Stoof Jeroen , Kuipers Ernst J. , Klaver Gerard , van Vliet Arnoud H. M.
Published: July 2010

The genomes of
Helicobacter
species colonizing the mammalian gastric mucosa (like
Helicobacter pylori
) contain a large number of genes annotated as iron acquisition genes but only few nickel acquisition genes, which contrasts with the central position of nickel in the urease-mediated acid resistance of these gastric pathogens. In this study we have investigated the predicted iron and nickel acquisition systems of the ferret pathogen
Helicobacter mustelae
. The expression of the outer membrane protein-encoding
frpB2
gene was iron and Fur repressed, whereas the expression of the ABC transporter genes
fecD
and
ceuE
was iron and Fur independent. The inactivation of the two
tonB
genes showed that TonB1 is required for heme utilization, whereas the absence of TonB2 only marginally affected iron-dependent growth but led to reduced cellular nickel content and urease activity. The inactivation of the
fecD
and
ceuE
ABC transporter genes did not affect iron levels but resulted in significantly reduced urease activity and cellular nickel content. Surprisingly, the inactivation of the
nixA
nickel transporter gene affected cellular nickel content and urease activity only when combined with the inactivation of other nickel acquisition genes, like
fecD
or
ceuE
. The FecDE ABC transporter is not specific for nickel, since an
fecD
mutant also showed reduced cellular cobalt levels and increased cobalt resistance. We conclude that the
H. mustelae fecDE
and
ceuE
genes encode an ABC transporter involved in nickel and cobalt acquisition, which works independently of the nickel transporter NixA, while TonB2 is required primarily for nickel acquisition, with TonB1 being required for heme utilization.
Oncospheral Penetration Glands and Secretory Blebs Are the Sources ofTaenia ovisVaccine Antigens
Authors: Jabbar Abdul , Crawford Simon , Gauci Charles G. , Walduck Anna K. , Anderson Garry A. , Lightowlers Marshall W.
Published: July 2010

Taenia ovisis a cestode parasite infecting primarily sheep as intermediate hosts and dogs as definitive hosts. The first highly effective, recombinant vaccine against a parasitic organism was developed againstT. ovisinfection in sheep. Three separate host-protective antigens (To16, To18, and To45W) have been cloned from the oncosphere of the parasite. We localize these antigens in the oncosphere by using quantitative immunogold labeling and transmission electron microscopy. The three antigens were uniquely associated with penetration gland cells. The cytoplasm and secretory granules of both penetration gland type 1 and type 2 cells exhibited statistically significant levels of staining for each of the three antigens. The intensity of labeling of the penetration gland type 1 cell was approximately three to five times greater (P< 0.01) compared to the level of staining intensity seen in the penetration gland type 2 cell. In activated oncospheres, secretory blebs were found to contain granules with a structure similar to those observed in the penetration gland cells. The granules within the secretory blebs were shown to stain specifically for the presence of each of the three host-protective antigens. The absence of surface location of theT. ovisantigens suggests that the parasite may not be susceptible to vaccine-induced antibody- and complement-mediated attack until some postoncospheral development has occurred after infection of the intermediate host.
Dynamic Polar Sequestration of Excess MurG May Regulate Enzymatic Function
Authors: Michaelis Allison M. , Gitai Zemer
Published: July 2010

Advances in bacterial cell biology have demonstrated the importance of protein localization for protein function. In general, proteins are thought to localize to the sites where they are active. Here we demonstrate that in
Escherichia coli
, MurG, the enzyme that mediates the last step in peptidoglycan subunit biosynthesis, becomes polarly localized when expressed at high cellular concentrations. MurG only becomes polarly localized at levels that saturate MurG's cellular requirement for growth, and
E. coli
cells do not insert peptidoglycan at the cell poles, indicating that the polar MurG is not active. Fluorescence recovery after photobleaching (FRAP) and single-cell biochemistry experiments demonstrate that polar MurG is dynamic. Polar MurG foci are distinct from inclusion body aggregates, and polar MurG can be remobilized when MurG levels drop. These results suggest that polar MurG represents a temporary storage mechanism for excess protein that can later be remobilized into the active pool. We investigated and ruled out several candidate pathways for polar MurG localization, including peptidoglycan biosynthesis, the MreB cytoskeleton, and polar cardiolipin, as well as MurG enzymatic activity and lipid binding, suggesting that polar MurG is localized by a novel mechanism. Together, our results imply that inactive MurG is dynamically sequestered at the cell poles and that prokaryotes can thus utilize subcellular localization as a mechanism for negatively regulating enzymatic activity.
Health-Related Quality of Life in Patients with Musculoskeletal Complaints in a General Acupuncture Practice: An Observational Study
Authors: van den Berg Ineke , Tan Loek , van Brero H , Tan K Tinka , Janssens A Cecile J W , Hunink M G Myriam
Published: July 2010

Background

Musculoskeletal complaints are associated with a large medical and societal burden. Although acupuncture is a frequently used therapy for musculoskeletal complaints, little is known about the effect on health-related quality of life (HRQoL).

Objectives

The aim of this study was to (i) compare the HRQoL of patients undergoing routine acupuncture treatment for musculoskeletal complaints with a Dutch population sample; (ii) investigate changes in HRQoL during the course of acupuncture treatment.

Methods

An observational study of 26 patients between 18 and 65 years of age in a single acupuncture practice was performed. HRQoL was measured on eight functional domains using a RAND-36 health survey at baseline and after six and 12 treatment sessions. Baseline RAND-36 scores were compared to data from a Dutch population sample (n=1063) using t test, and longitudinal data were analysed using repeated measurement analyses.

Results

At baseline, patients had significantly lower RAND-36 scores compared to the Dutch population sample for three domains: role-physical limitations (51.9 vs 79.4; p<0.001), bodily pain (49.3 vs 79.5; p<0.001) and social functioning (75.5 vs 86.9; p=0.005). During the course of treatment, RAND-36 scores increased significantly for five domains: physical functioning (79.3 vs 97.4; p<0.001), role-physical functioning (51.4 vs 94.1; p<0.001), bodily pain (47.3 vs 95.7, p<0.001), social functioning (74.5 vs 92.0, p<0.001) and vitality (69.1 vs 85.7; p<0.001).

Conclusion

The observed improvements in HRQoL suggest a subjective, clinically relevant, benefit of routine acupuncture therapy in treating musculoskeletal complaints.
Developing and Validating a Sham Cupping Device
Authors: Lee Myeong Soo , Kim Jong-In , Kong Jae Cheol , Lee Dong-Hyo , Shin Byung-Cheul
Published: July 2010

Objectives

The aims of this study were to develop a sham cupping device and to validate its use as a placebo control for healthy volunteers.

Methods

A sham cupping device was developed by establishing a small hole to reduce the negative pressure after suction such that inner pressure could not be maintained in the cup. We enrolled 34 healthy participants to evaluate the validity of the sham cupping device as a placebo control. The participants were informed that they would receive either real or sham cupping and were asked which treatment they thought they had received. Other sensations and adverse events related to cupping therapy were investigated.

Results

17 patients received real cupping therapy and 17 received sham cupping. The two groups felt similar sensations. There was a tendency for subjects to feel that real cupping created a stronger sensation than sham cupping (48.9±21.4 vs 33.3±20.3 on a 100mm visual analogue scale). There were only mild to moderate adverse events observed in both groups.

Conclusion

We developed a new sham cupping device that seems to provide a credible control for real cupping therapy by producing little or no negative pressure. This conclusion was supported by a pilot study, but more rigorous research is warranted regarding the use of this device.
In vitro regeneration of plantlets of Scots pine (Pinus sylvestris) with mycorrhizal roots from subcultured callus initiated from needle adventitious buds
Authors: Supriyanto  , Rohr R.
Published: July 2010

Plantlets were regenerated from cultures established from Pinus sylvestris (Scots pine) meristematic tissue. Seedling explants were first stimulated to develop axillary buds. Developing axillary buds produced numerous new meristems that gave rise to globular adventitious buds located along the needles on half-strength modified Murashige and Skoog medium supplemented with coconut milk and 6-benzylaminopurine. A histological study showed that these new buds originated from dedifferentiated mesophyll and epidermal tissues of the needles. Some of these buds were used for the regeneration of whole plantlets, others were excised and transferred to woody plant medium, on which calli developed at the bases of the microcuttings These calli were organogenic when subcultured on a hormone-free medium and initiated a large number of rooted plantlets that showed high potential to multiply themselves indefinitely. This is the first report of regeneration of Scots pine from a subculturable organogenic line. Mycorrhizae were initiated for both types of plantlets with Hebeloma cylindrosporum on a perlite substrate under fully controlled conditions. Mycorrhizae improved the transfer of the plantlets to ex vitro conditions. Key words: organogenesis, mycorrhizae, tissue culture, Pinus sylvestris.
Tranzschelia asiatica sp.nov. and its taxonomic relationship to Tranzschelia arthurii
Authors: Ono Yoshitaka
Published: July 2010

Prunus grayana (subg. Padus) was found to serve as the uredinial-telial host of two distinct Tranzschelia species in Japan. Tranzschelia pruni-spinosae has been known to occur on P. grayana, and the other species was previously overlooked. The latter fungus was experimentally proven to form its spermogonial and aecial stages on Hepatica nobilis var. japonica f. variegata and f. magna. The fungus was similar in morphology and host relationships to Tranzschelia arthurii, whose spermogonial and aecial stages occur on H. nobilis var. acuta and uredinial and telial stages on Prunus serotina and Prunus virginiana (subg. Padus) and Prunus americana (subg. Prunophora) in North America. However, the spores at all stages in the life cycle of the Japanese fungus were significantly smaller than those of the North American fungus. Because of this, a new species, Tranzschelia asiatica, was proposed for the geographically separated fungus. This species is expected to occur in East Asia outside of Japan, but this is not yet confirmed. Key words: rust fungus, Uredinales, Rosaceae, Prunus, Ranunculaceae, Hepatica.
Genetic analysis of pyriform microconidium production in mating population B of Gibberella fujikuroi
Authors: Chen Fa-Jun
Published: July 2010

Isolates of Fusarium subglutinans that differ in their ability to produce globose or pyriform microconidia were sexually compatible members of mating population B of Gibberella fujikuroi. Single ascospore isolates from these matings segregated 1:1 for the production of globose or pyriform microconidia, suggesting that a single Mendelian gene controls production of globose or pyriform microconidia. The validity of Fusarium anthophilum as an anamorph species is questioned. Key words: pyriform microconidium, single gene, Fusarium subglutinans, Fusarium anthophilum.
The effect of suberin lamellae on the vitality and symplasmic permeability of the onion root exodermis
Authors: Peterson Carol A. , Waite Janet L.
Published: July 2010

The onion exodermis is made up of two cell types, i.e., long and short cells. Both form Casparian bands, but suberin lamella development is absent or delayed in the short cells. Long cells did not accumulate fluorescein, a common test for cell vitality, because of reduced wall permeability due to suberin lamella development. Immature, long cells without lamellae stained in 15 min, whereas mature cells with lamellae required a 3.5- to 4-h treatment before staining was visible. Long exposure to fluorescein was needed to show that mature long cells were alive. Their vitality appeared to decline slowly with age but was not affected by drought stress. Fluorescein staining was apparent in the long cells only after treatment of paradermal sections; when dye was applied only externally to root segments, it did not enter the long cells from the epidermis or from the neighbouring short cells. This result indicates that the long cells were connected symplasmically to the cells of the cortex but were either unconnected, or connected by plasmodesmata of small functional diameter, to the epidermal and short cells. If they were unconnected, they would not form part of the symplasmic path of ion transfer into the root. Keywords: Allium cepa L., drought, exodermis, suberin lamella, vitality.
Growth and survival of white clover (Trifolium repens) transplanted into patches of different grass species
Authors: Mehrhoff Loyal A. , Turkington Roy
Published: July 2010

Previous studies on Trifolium repens L. showed differentiation with respect to neighbouring plant species and local environmental conditions. In this study, we conducted a series of reciprocal transplants among and within different pastures and among neighbouring grass species (Lolium perenne L., Dactylis glomerata L., and Holcus lanatus L.). While the presence of a grass neighbour decreased survival and growth of T. repens, no evidence of differentiation by T. repens to either local environmental conditions or to neighbouring grass species was found. We suggest that T. repens, in systems like our study pastures that have small, transient grass patches, may show inconsistent and ephemeral responses to the presence of neighbouring plants, whereas in other systems with larger grass patch size and a longer period of exposure to selection processes, T. repens show fine-scale biotic differentiation to neighbouring grass species. Keywords: population differentiation, white clover, selection, microevolution, transplantation.
Développement de quelques Fagaceae japonaises; germination, modèle architectural et systématique
Authors: Soumoy L. , Thiébaut B. , Sérey I.
Published: July 2010

In European and American species of Fagaceae, the growth and the shape of axes can be different between seedlings and trees. Furthermore, in this family, a good connection appears between the architectural model and the genus, because oaks grow according to the Rauh model, chestnut trees according to the Massart model, and beeches according to the Troll model. By studying 13 other species from Japan with unknown architectural traits, we complete our knowledge on growth and morphology of Fagaceae. The architectural characters were described on seedlings 1- to 4-years-old grown in the open air, in an experimental field, and on trees of all ages grown in forests. The relationships in architecture between seedlings and trees and the systematic status of these species in the Fagaceae were analyzed. Keywords: Fagaceae, morphology, architecture, germination, systematic.
Components of resistance in barley to stem rust: pre- and post-penetration development in seedling and adult plant leaves
Authors: Liu J. Q. , Harder D. E.
Published: July 2010

Seven barley (Hordeum vulgare) cultivars or breeding lines with different levels of resistance to stem rust and the susceptible wheat cultivar Little Club (Triticum aestivum) were inoculated with races QCC, QFC, and TPM of Puccinia graminis f.sp. tritici and examined using light microscopy to associate the sequence of histological events with phenotypic expression of resistance. There were no significant differences in urediniospore germination, appressorium formation, or substomatal penetration in any of the race–cultivar combinations in seedling leaves. Formation of primary haustorium mother cells (HMCs) was not affected by the presence or absence of the resistance gene Rpg1 when inoculated with race QCC, but was reduced considerably in lines possessing this gene after inoculation with races QFC and TPM. Development of all races was arrested during primary HMC formation to a greater extent in all barley lines than in Little Club wheat. The expression of resistance in barley to P. g. tritici was associated with the frequency of post-penetration abortion, the degree of reduction in colony growth, and the incidence of colony-associated necrosis of host cells. The rankings of the host lines based on these histological events were in agreement with the rankings for receptivity and urediniospore production determined previously on stem tissues of adult barley plants. Keywords: barley, stem rust, resistance, components, histology.
Effects of burial of seeds and seedlings from different seed sizes on the emergence and growth of Strophostyles helvola
Authors: Yanful Mary , Maun M. A.
Published: July 2010

Field and greenhouse studies were conducted to examine the role of seed mass in (i) the emergence of seedlings of Strophostyles helvola (L.) Ell. from different depths of burial in sand and (ii) the ability of seedlings originating from seeds of different seed mass (weight per seed) to re-emerge from sand deposits. Seeds were sorted into four different seed mass classes (small, < 55 mg; medium, 55–65 mg; large, 65–75 mg; and extra large, > 75 mg) and sown at different depths ranging from 2 to 24 cm in sand on a sandy beach at Port Burwell Provincial Park along Lake Erie. Seeds of large mass class (65–75 mg) sown at 18 cm depth produced the largest plants. Under greenhouse conditions, all S. helvola seedlings buried to 100 and 125% of their height survived the treatment, but survival declined to 66% when they were buried to 150% of their height. Stimulation in growth was observed only when the seedlings were buried to 50 and 75% of their height. Seedlings originating from large seed masses took fewer days to re-emerge from different burial depths than seedlings from small seeds. However, the interaction term between seed mass and burial depth for the re-emergence of seedlings was not significant. Keywords: seed mass, burial of seeds, burial of seedlings, Strophostyles helvola, seedling emergence.
Discostroma tricellulare, a new endophytic ascomycete with a Seimatosporium anamorph isolated from Rhododendron
Authors: Okane Izumi , Nakagiri Akira , Ito Tadayoshi
Published: July 2010

A new endophytic ascomycete inhabiting three ericaceous plants, Rhododendron indicum, Rhododendron macrosepalum, and Rhododendron obtusum, is described as Discostroma tricellulare sp.nov. (Amphisphaeriaceae). This fungus produces three-celled, biseriate ascospores in unitunicate asci that have an amyloid ring in the apical apparatus. Its anamorph is named Seimatosporium azaleae sp.nov. Keywords: Discostroma tricellulare, Seimatosporium azaleae, Ascomycetes, Rhododendron, endophytic fungi, Amphisphaeriaceae.
The potential identification of the geographic origin of lobster eggs from various wild stocks based on fatty acid composition
Authors: Castell John D. , Boston Linda D. , Miller Robert J. , Kenchington Trevor
Published: July 2010

The fatty acids of lipids from eggs of five lobsters (Homarus americanus) collected at Brown's Bank (offshore), Lobster Bay (near shore), and Hunt's Point (near shore) were analyzed to determine whether compositional patterns might be used to distinguish offshore from near-shore lobsters. Offshore samples had a higher content of monoenoic fatty acids, lower levels of 20:5n–3 and higher levels of 22:6n–3 than near-shore samples. All Hunt's Point samples contained about twice as much 20:4n–6 (4.81 ± 1.48%) as samples from other locations (2.05 ± 0.53% and 2.85 ± 0.75% for Lobster Bay and Brown's Bank, respectively). Similarly, the total percentages of n–6 fatty acids of Hunt's Point lobster eggs were significantly higher than samples from the other two locations (8.13 ± 1.31% vs. 4.28 ± 0.49% and 5.11 ± 1.08%). The content of 18:1n–9, 20:1n–5, 20:2n–6, 20:4n–6 and 21:5n–3 differed significantly among subsamples from different geographic locations. Only with 21:5n–3 was there no overlap in the percentage content between Lobster Bay lobsters and lobsters from the other two locations. Although no fatty acid was specific enough to distinguish eggs from any one location, discriminant analysis of fatty acids proved effective in identifying offshore from near-shore lobsters.
Mercury in remote Rocky Mountain lakes of Glacier National Park, Montana, in comparison with other temperate North American regions
Authors: Watras C. J. , Morrison K. A. , Bloom N. S.
Published: July 2010

We determined concentrations of mercury (Hg) and methylmercury (MeHg) in 12 pristine lakes of Glacier National Park (GNP) and compared our observations with data from published studies of remote lakes in north-central Wisconsin and the Adirondack region of New York. Despite marked differences in water chemistry, biology, and hydrogeology, concentrations of Hg and MeHg in all regions were strongly correlated with dissolved organic carbon (DOC). Variables related to the acid–base status of lake waters had secondary effects on the concentration of waterborne mercury species. Although Hg and MeHg were strongly correlated with DOC in all three regions, MeHg concentrations were lower and increased less per unit organic carbon in GNP lakes than in either Wisconsin or New York. In GNP lakes, MeHg averaged only 4 ± 2% (mean ± SD) of the Hg, while in Wisconsin and New York lakes MeHg averaged 10–14% of the Hg. Based on simple regression modelling, we estimate that the maximum MeHg fraction (MeHg/Hg) in dystrophic GNP lakes would be three- to six-fold lower than in Wisconsin or New York waters of similarly high DOC. Our results suggest that this regional difference involves factors regulating the net production of MeHg in lakes or watersheds.
Impact of a major soil fumigant spill on the planktonic ecosystem of Shasta Lake, California
Authors: Brett Michael T. , Goldman Charles R. , Lubnow Frederick S. , Müller-Solger Anke , Bracher Astrid , Brandt Darren , Brandt Odette
Published: July 2010

On July 14, 1991, approximately 70 000 L of the soil fumigant Vapam®, metam sodium, was spilled into the upper Sacramento River, California. Twelve hours before this spill reached Shasta Lake we sampled several sites in a subsequently impacted area and two control stations. Thereafter, samples were collected at approximately 5-d intervals for 26 d. We observed an almost immediate and subsequent 99.9% decrease in zooplankton biomass within 2.0 km of the river inflow. Lake-water chlorophyll concentrations crashed immediately to 20% of prespill values, but rebounded to approximately 750% prespill values after 9 d as a result of a spill-driven diatom bloom. Dissolved inorganic nitrogen and phosphorus concentrations increased severalfold immediately after the spill but returned to prespill concentrations as the algal bloom peaked. Effects of the spill were clearly related to distance from the river inflow with strong effects observed within 2.0 km, and weak or no effects observed at 8.0 km into the reservoir. A dilution experiment, using varying mixtures of contaminated and control station lake water, strongly confirmed the principal findings of the field study. Our field and experimental data showed far more severe effects of the spill than single species bioassays and lake pesticide concentrations predicted.
The effect of forest floor manipulation on nitrogen status and tree growth in an eastern Ontario jack pine ecosystem
Authors: Weber M. G. , Methven I. R. , Wagner C. E. Van
Published: July 2010

Four forest floor manipulation treatments were applied to an eastern Ontario jack pine (Pinusbanksiana Lamb.) ecosystem. These included a one-time complete removal of the forest floor to mineral soil; annual removal of the total forest floor to mineral soil; one-time removal of the forest floor, ashing of the material, and broadcast spreading of the ash onto exposed mineral soil; and an untreated control. Eight years after treatment radial tree growth on the treated plots showed a 30% reduction compared with the untreated plot. Annual removal of the forest floor caused most severe nitrogen depletion in jack pine foliage, forest floor, and mineral soil. Effects of one-time removal and burning treatments were less severe, but significant. Any interference with the normal buildup of the forest floor during stand development should be avoided if site quality is to be maintained for tree growth.
Harmonizing biomass tables by generalized least squares
Authors: Cunia T. , Briggs R. D.
Published: July 2010

To construct biomass tables for various tree components that are consistent with each other, one may use linear regression techniques with dummy variables. When the biomass of these components is measured on the same sample trees, one should also use the generalized rather than ordinary least squares method. A procedure is shown which allows the estimation of the covariance matrix of the sample biomass values and circumvents the problem of storing and inverting large covariance matrices. Applied to 20 sets of sample tree data, the generalized least squares regressions generated estimates which, on the average were slightly higher (about 1%) than the sample data. The confidence and prediction bands about the regression function were wider, sometimes considerably wider than those estimated by the ordinary weighted least squares.
Interaction between gibberellin A4/7 and root-pruning on the reproductive and vegetative processes in Douglas-fir. III. Effects on anatomy of shoot elongation and terminal bud development
Authors: Owens J. N. , Webber J. E. , Ross S. D. , Pharis R. P.
Published: July 2010

The relative importance of cell division and cell elongation to shoot elongation and the anatomical changes in vegetative terminal apices were assessed for 9- and 10-year-old seedlings of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) in response to two effective cone-induction treatments, gibberellin A4/7 (GA4/7) and root-pruning (RP). Root-pruning was done in mid-April at the start of vegetative bud swelling and GA treatments were begun at vegetative bud flushing in mid-May and continued until early July. Shoot elongation before flushing resulted primarily from cell divisions and was not affected by the RP treatment. Shoot elongation after flushing resulted primarily from cell expansion which was reduced by RP treatments. Root-pruning significantly slowed mitotic activity, apical growth, and development of vegetative terminal buds from mid-June through mid-July. Apical growth then resumed during leaf initiation and the final number of leaf primordia initiated was not affected. This resulted in a delay of 2 to 4 weeks in the transition from bud-scale to leaf initiation. Retarded terminal vegetative apices anatomically resembled latent axillary apices but were never completely inhibited. GA + RP had the same effect as RP. GA4/7 alone had no effect on shoot or apical development. These results show that RP and GA + RP significantly retard shoot elongation and terminal bud development but still allow normal development of vegetative terminal buds. Retardation of bud development by a few weeks shifts the critical morphogenetic phase of transition from bud scale to leaf initiation to a later time when endogenous and environmental conditions may differ from the normal.
Early vegetation recovery and element cycles on a clear-cut watershed in western Oregon
Authors: Gholz Henry L. , Hawk Glenn M. , Campbell Alsie , Cromack Jr. Kermit , Brown Alfred T.
Published: July 2010

Aboveground biomass and leaf area, net primary production, and nutrient cycling through vegetation were studied for 3 years after clear-cutting (stems only) of a 10.24-ha watershed in the Oregon Cascade Mountains. The riparian zone and four main habitats were analyzed separately. In 3 years, aboveground net primary production increased from 5 to 112 g•m−2•year−1 in the ridgetop habitat; midsummer aboveground biomass increased from 8 to 196 g/m2 in the riparian zone and from 198 to 327 g/m2 on the ridgetop. Other values were intermediate to these. Litter fall of species with perennial aboveground parts averaged 20–27% of standing biomass. Native annuals, especially Araliacalifornica Wats., dominated the riparian zone. Seneciosylvaticus L., an introduced species, dominated most of the rest of the watershed, except for the ridgetop habitat, which was dominated by residual woody shrubs. Uptake of N exceeded losses in streamflow the 1st year and was six times greater in the 2nd; uptake of P and K in that year was 2.5 and 3 times greater than losses. In the 3rd year, total uptake of K (2.5 g•m−2•year−1) equaled the preclear-cutting level, and uptake of N (1.3 g•m−2•year−1) and P (0.3 g•m−2•year−1) was about half that level. No correlation was found between plant uptake and nutrient loss in streamflow. Uptake of all elements exceeded return through leaching and litter fall by 16%, except that of Mg, which exceeded return by 44%. Because of early dominance by species with annuals, the proportion of elements redistributed internally by vegetation was generally low. The amount of nutrients in flux through vegetation, atmosphere, and stream was small in comparison to the amount lost in the removal of tree stems.
Genetic variation in eastern white spruce (Piceaglauca (Moench) Voss) populations
Authors: Khalil M. A. K.
Published: July 2010

The paper discusses the magnitude and trends in genetic variation in eastern white spruce (Piceaglauca (Moench) Voss) populations on the basis of 20-year results. Provenances exhibit two east–west clines as a result of the significant influence of the environmental factors at their sources on their performance at the test site. The sensitivity of white spruce to differences in soil conditions, detected earlier, is confirmed and is found to increase with age. Though crown width is largely under environmental control some genetic variation is possible. Provenances from the region between latitudes 45 and 50° N and longitudes 67 and 80° W are superior in growth and form and are homeostatic. Intraprovenance variation is large, providing opportunity for genetic improvement by plus-tree selection in these superior provenances. Provenances with superior growth in the nursery maintained superior growth in the field.
Longitudinal changes in the stem growth layer associated with debudding and branch development in red pine
Authors: Fayle David C. F.
Published: July 2010

Ring widths were measured in two red pine (Pinusresinosa Ait.) trees debudded at the start of years 7–14 inclusive from planting, and felled when 25 and 46 years old, respectively. Changes in the form of the growth layer are discussed, and general comparisons for radial and height increment made with nondebudded trees. When no branches were present at annual nodes owing to debudding, the width of the growth layer increased basally in the first few internodes and then decreased uniformly along the internodes, before becoming constant in the lower ones. Width did not change at the annual nodes, other than at the first. In contrast, when branch development was reestablished, the width of the growth layer changed at the annual nodes and the pattern was also altered within the internodes of the new crown. In addition, redistribution of thickening occurred along the stem below the new crown, and height increment was reduced. These changes are discussed in relation to probable alterations in mechanical stresses and other factors.
A soil temperature control system for plant research
Authors: Waldren D. W. , McKinnis M. K. , Carlson W. C.
Published: July 2010

A soil temperature control system is described which allows control of soil temperature ± 1.1 °C, maintenance of water-bath level and pot placement during irrigation, and unrestricted soil drainage. The system also allows the use of a large number of pots (300) held at each soil temperature, with a capacity of three seedlings per pot, and is constructed of low-cost, readily available materials. This system facilitates the use of large experimental designs with relatively low labor inputs during the experiment.
Properties of the quadratic mean diameter in balanced diameter distributions
Authors: Weatherhead Donald J. , Chapman Roger C. , Bassman John H.
Published: July 2010

Balanced diameter distributions are widely used to describe stand structure goals for residual growing stock in uneven-aged forests. The quadratic mean diameter is frequently used as a descriptor of a balanced diameter distribution. In this paper the quadratic mean diameter is shown to be independent of stand basal area for balanced diameter distributions with a common class width, maximum and minimum diameters, and de Liocourt's q ratio. Additionally it is shown that the quadratic mean diameter is relatively insensitive to changes in maximum tree size and q ratios for q ratios 1.5 and larger.
THE TOPOLOGY OF A LOCAL TRADE WEB AND IMPACTS OF THE US FINANCIAL CRISIS
Authors: FENG XIAOBING , HU HAIBO , WANG XIAOFAN
Published: July 2010

In this paper a local trade web (LTW) in the Asia-Pacific region is examined using the data derived from the United Nations and the International Monetary Fund. The topology of the LTW has been specified, based upon which the impacts of US financial crisis on the structural and behavior pattern of the LTW are further investigated. The major findings are given as follows. Firstly, the LTW is much more integrated than the global trade web; secondly, after the financial crisis, the fundamental structure of the network remains relatively stable but the strength of the web has been changed and the structure of the web has evolved over time. Economic implications for what have been observed are also discussed.
INVASION PERCOLATION WITH A HARDENING INTERFACE UNDER GRAVITY
Authors: OLIVEIRA C. L. N. , WITTEL F. K. , ANDRADE J. S. , HERRMANN H. J.
Published: July 2010

We propose a modified Invasion Percolation (IP) model to simulate the infiltration of glue into a porous medium under gravity in 2D. Initially, the medium is saturated with air and then invaded by a fluid that has a hardening effect taking place from the interface towards the interior by contact with the air. To take into account that interfacial hardening, we use an IP model where capillary pressures of the growth sites are increased with time. In our model, if a site stays for a certain time at interface, it becomes a hard site and cannot be invaded anymore. That represents the glue interface becoming hard due to exposition with the air. Buoyancy forces are included in this system through the Bond number which represents the competition between the hydrostatic and capillary forces. We then compare our results with results from literature of non-hardening fluids in each regime of Bond number. We see that the invasion patterns change strongly with hardening while the non-hardening behavior remains basically not affected.
ANTICIPATION DRIVING BEHAVIOR AND RELATED REDUCTION OF ENERGY CONSUMPTION IN TRAFFIC FLOW
Authors: SHI WEI , WEI YAN-FANG , SONG TAO , DAI SHI-QIANG , DONG LI-YUN
Published: July 2010

In view that drivers would pay attention to the variation of headway on roads, an extended optimal velocity model is proposed by considering anticipation driving behavior. A stability criterion is given through linear stability analysis of traffic flows. The mKdV equation is derived with the reductive perturbation method for headway evolution which could be used to describe the stop-and-go traffic phenomenon. The results show a good effect of anticipation driving behavior on the stabilization of car flows and the anticipation driving behavior can improve the numerical stability of the model as well. In addition, the fluctuation of kinetic energy and the consumption of average energy in congested traffic flows are systematically analyzed. The results show that the reasonable level of anticipation driving behavior can save energy consumption in deceleration process effectively and lead to an associated relation like a "bow-tie" between the energy-saving and the value of anticipation factor.
MONTE CARLO SIMULATION OF POSITIVE CORONA DISCHARGE IN NITROGEN
Authors: SETTAOUTI A. , SETTAOUTI L.
Published: July 2010

The corona discharge commonly occurs in many engineering devices and processes. Their application is still largely based on empirical knowledge; accordingly it is very important to predict the physical properties of corona discharge by the appropriate numerical method. To control corona discharge properly by understanding of corona discharge properties at different discharge stages, time-varying characteristics of discharge which are resulted from electron collision with the gas molecules should be investigated. A numerical study of a corona discharge in nitrogen in a point to plane geometry is presented. It is obtained by Monte Carlo method and concerns space-time evolution of electron and ion densities as well as electric field distributions along the discharge axis.
SELF-STABILIZING VERTEX COVER IN ANONYMOUS NETWORKS WITH OPTIMAL APPROXIMATION RATIO
Authors: TURAU VOLKER
Published: July 2010

This paper presents a deterministic self-stabilizing algorithm that approximates a minimum vertex cover in anonymous networks with ratio 2 using the distributed scheduler and the link-register model with composite atomicity. No algorithm with a better approximation ratio can exist. The algorithm stabilizes in O( min {n, Δ2, Δ log 3 n}) rounds and requires O(Δ) memory per node.
Thermoelectric Properties of Polycrystalline Ca0.9Yb0.1MnO3 Prepared from Nanopowder Obtained by Gas-Phase Reaction and Its Application to Thermoelectric Power Devices
Authors: Kosuga Atsuko , Wang Yifeng , Yubuta Kunio , Koumoto Kunihito , Funahashi Ryoji
Published: July 2010

Ca0.9Yb0.1MnO3 nanopowder prepared by a gas-phase reaction (GPR) consisted of well-dispersed particles with an average diameter of 47 nm. Sintering of this GPR powder proceeded rapidly and at a lower temperature than that required for a comparable powder prepared by conventional solid-state reaction (SSR). The sintered bulk material from the GPR powder (GPR-bulk) consisted of small grains with an average diameter of 620 nm; this morphology is completely different to that of the SSR-bulk in which larger grains bind together to form a network-like structure. A maximum power factor of 0.19 mW·m-1·K-2 was obtained for GPR-bulk at 973 K; this value is higher than that of SSR-bulk, mainly as a result of the lower electrical resistivity of GPR-bulk. The thermal conductivity of GPR-bulk is also lower than that of SSR-bulk, possibly because of increased phonon scattering at the grain boundary. The maximum value of the dimensionless figure of merit of 0.13 was obtained for GPR-bulk at 1073 K; this value is about 1.5-fold higher than that for SSR-bulk at 773 K. A unicouple device consisting of a p-type Ca2.7Bi0.3Co4O9 leg and an n-type Ca0.9Yb0.1MnO3 (GPR-bulk) leg was fabricated. Both oxide legs used for the measurement are 3.1–3.5 mm in both width and thickness and ∼5 mm in height. The device generated up to 0.14 W of power when the hot- and cold-side temperatures at the ends of the oxide legs were 1095 and 390 K, respectively.
Method of Decoupling the Bias Temperature Instability Component from Hot Carrier Degradation in Ultrathin High-k Metal–Oxide–Semiconductor Field-Effect Transistors
Authors: Masada Akiko , Hirano Izumi , Fukatsu Shigeto , Mitani Yuichiro
Published: July 2010

Hot-carrier (HC) degradation becomes more critical as the channel length is reduced. Furthermore, both positive and negative bias temperature instabilities (PBTI and NBTI, respectively) are significant in high-k devices. Under HC stress, BTI caused by the vertical electric field is unavoidable. The decoupling of the BTI component from HC degradation is necessary to predict device lifetime more accurately. In this study, a new decoupling method of HC degradation is proposed. By using the relation between ΔV
th and J
g, the BTI component can be decoupled from the degradation under V
g=V
d stress. The application of our method to HfSiON metal–oxide–semiconductor field-effect transistors (MOSFETs) is demonstrated. The channel length dependence of each component shows the improvement resulting from the decoupling method. Furthermore, the activation energy of the NBTI component in HC degradation coincides with that of NBTI.
Optimization of the Growth Conditions for Molecular Beam Epitaxy of MgxZn1-xO (0≤x≤0.12) Films on Zn-Polar ZnO Substrates
Authors: Yuji Hiroyuki , Nakahara Ken , Tamura Kentaro , Akasaka Shunsuke , Nishimoto Yoshio , Takamizu Daiju , Onuma Takeyoshi , Chichibu Shigefusa F. , Tsukazaki Atsushi , Ohtomo Akira , Kawasaki Masashi
Published: July 2010

We report on optimization of the growth conditions for MgxZn1-xO (x=0,0.04,0.05,0.12) thin films grown onc-plane Zn-polar ZnO single crystal substrates by using plasma-assisted molecular beam epitaxy (PAMBE). A normal vector to the ZnO substrate surfaces was angled at 0.5±0.1° off from the [0001]c-axis toward the [1100] direction, leading to a stable step-and-terrace structure. A growth temperature (Tg) higher than 800 °C led to the ZnO films presenting the first excited state luminescence of A-free excitons in photoluminescence (PL) spectra at 12 K. ATghigher than 800 °C enhanced optical attributes of a MgxZn1-xO film. The longest PL lifetime of fast-decay components reached 3.5 ns in time-resolved PL measurement for an Mg0.12Zn0.88O film grown at 900 °C, indicating a concentration of nonradiative recombination centers is substantially eliminated compared to the previously reported PL lifetime of 60 ps for an Mg0.11Zn0.89O film grown by pulsed laser deposition.
Improved Dielectric Properties of Low-Temperature-Sintered (Ba,Sr)TiO3-Based Ceramics by Ge Substitution
Authors: Ha Jong-Yoon , Yoon Seok-Jin , Jeong Dae-Yong , Choi Ji-Won
Published: July 2010

Multilayer microwave dielectric materials with low sintering temperature are required for microwave phase shifters, filters, and true-time delay devices. We investigated the sintering and dielectric properties of (Ba0.6Sr0.4)(Ti1-x
Ge
x
)O3 (BSTG; 0.05≤x≤0.3) ceramics. As the Ge concentration was increased, the lattice constant of BSTG ceramics decreased, and Ba2Ge2TiO8, which is the liquid phase at low temperature, was formed. Ba2Ge2TiO8 liquid phase may increase the sintering density. The effect of Ge substitution is the decrease in the sintering temperature from over 1400 to 1150 °C in BST system ferroelectric ceramics. With increasing Ge concentration, the dielectric constant decreased from 2190 to 530, and the dielectric loss decreased up to 0.001 (at 1 MHz) with sintering at 1150 °C for 2 h. When Ge was substituted at 0.05 and 0.1 mol of Ti in the BST at 1150 °C, the dielectric constant, dielectric loss, tunability, Curie temperature, and figure of merit were 2184 and 1529, 0.002 and 0.001, 27 and 23%, -11 and -18 °C, and 135 and 230, respectively. These compositions show microwave dielectric properties comparable to those of (Ba0.5Sr0.5)TiO3 ferroelectrics, which are the important materials for tunable devices such as varactors, phase shifters, and frequency agile filters.
The Charge Transport in Organic Field-Effect Transistor as an Interface Charge Propagation: The Maxwell–Wagner Effect Model and Transmission Line Approximation
Authors: Weis Martin , Lin Jack , Taguchi Dai , Manaka Takaaki , Iwamoto Mitsumasa
Published: July 2010

By analyzing electric field migration in the pentacene organic field-effect transistor channel (OFET), visualized using the time-resolved microscopic optical second harmonic generation (TRM-SHG) is analyzed the propagation of injected carriers. We find that the accumulated charge propagation on the pentacene–gate insulator interface of the three-electrode system is clearly different from the drift in electric field of the two-electrode system. The propagation of injected carriers is evaluated on the basis of the Maxwell–Wagner effect model and the transmission line approximation. We show that the interface charge accumulation has a significant contribution to the charge transport in OFET. Proposed model for the transient state is beyond the limits of common used impedance spectroscopy models and represents extension of the small-signal analysis. Found relation between mobility and transit time helps in analysis of OFET transit time sensitive experiments such as the time-of-flight technique (TOF) or TRM-SHG.
Thermal Stability of Liquid Crystals on Blended Polyimide Layers Treated by Ion Beam Irradiation
Authors: Kim Dai-Hyun , Park Hong-Gyu , Kim Young-Hwan , Kim Byoung-Yong , Ok Chul-Ho , Han Jeong-Min , Seo Dae-Shik
Published: July 2010

We demonstrated the annealing effects displayed by liquid crystal antiparallel cells made from ion beam-irradiated blended polyimide layers. The pretilt angles of the liquid crystals after annealing at 90 °C for 10 min were similar to those before annealing, which demonstrates good thermal stability for liquid crystal antiparallel cells. Contact angle increases as vertical polyimide concentration increases, a trend that corresponds closely to the variation in pretilt angle. Uniform liquid crystal alignment was observed from a photomicrograph. Strong anchoring energies allowed the liquid crystal to maintain homeostasis and withstand thermal stress.
Self-Heating Effect on the Two-State Lasing Behaviors in 1.3-µm InAs–GaAs Quantum-Dot Lasers
Authors: Ji Hai-Ming , Yang Tao , Cao Yu-Lian , Xu Peng-Fei , Gu Yong-Xian , Wang Zhan-Guo
Published: July 2010

Experimental and theoretical study of the self-heating effect on the two-state lasing behaviors in 1.3-µm self-assembled InAs–GaAs quantum dot (QD) lasers is presented. Lasing spectra under different injected currents, light–current (L–I) curves measured in continuous and pulsed regimes as well as a rate-equation model considering the current heating have been employed to analyze the ground-state (GS) and excited-state (ES) lasing processes. We show that the self-heating causes the quenching of the GS lasing and the ES lasing by the increased carrier escape rate and the reduced maximum modal gain of GS and ES.