bluuebunny/crossref_metadata_2025 huggingface dataset:
PHIALOPHORA RADICICOLA CAIN, A CORN ROOTROT PATHOGEN
Authors: McKeen W. E.
Published: June 2008

During the summer of 1950, Phialophora radicicola, was found on corn roots in soil near Chatham, Ridgetown, and Harrow, Ont. Owing to its color and parasite-host relations, it may have been mistaken previously for Rhizoctonia solani or a Rhizophagus species. It can be isolated only when a piece of apparently healthy corn root tissue with the adhering mycelium is removed from an infected root and placed on agar media. After two or three months of culture on nutrient and on potato dextrose agar, P. radicicola lost its ability to sporulate, but this ability was revived when it was cultured on moist corn roots. No sexual stage of the organism has been found. The fungus may attack corn roots at any time throughout the season and its brown runner-hyphae or macrohyphae grow parallel to the roots. The finer infection hyphae or microhyphae penetrate the outer root tissue and their infection threads are surrounded by "wall tubules". The fungus is quite aggressive, but not very pathogenic, and apparently it is followed by numerous secondary organisms. The similarity of this organism to Ophiobolus graminis is very noticeable.
Developmental studies on Euphorbia esula. The influence of the nitrogen supply on the correlative inhibition of root bud activity
Authors: McIntyre Gordon I.
Published: June 2008

When seedlings of leafy spurge (Euphorbia esula L.) were grown at a low nitrogen level (10.5 ppm) the growth of the lateral buds on the shoot was completely arrested by apical dominance while the buds on the roots, although also inhibited, showed considerably greater activity. At a higher nitrogen level (210 ppm) apical dominance was markedly reduced but the resulting outgrowth of the lateral buds increased the inhibiting capacity of the shoot, limiting root bud response. When the main shoot was decapitated the degree to which root bud growth was suppressed by a given number of lateral shoots was inversely related to the nitrogen supply. Inhibition of the root buds by the lateral shoots could be significantly reduced by growing the plants initially at a low nitrogen level so that growth of the lateral buds was arrested. A subsequent increase in the nitrogen supply strongly promoted the growth of the roots buds, some of which were sufficiently released from inhibition to emerge as leafy shoots.
North American species of Coprotus (Thelebolaceae: Pezizales)
Authors: Kimbrough James W. , Luck-Allen E. R. , Cain Roy F.
Published: June 2008

The genus Coprotus is a segregate of the coprophilous genus Ascophanus Boud. characterized by minute, translucent, white to yellow apothecia, operculate, non-amyloid, eight- to multi-spored asci, and hyaline, smooth, thin-walled ascospores that contain gas bubbles. Species are distinguished by (1) the number of spores per ascus, (2) the presence or absence of pigments in paraphyses and excipular cells, and (3) the relative size and shape of asci, spores, and sterile elements. Five new combinations are made and six new species are proposed. Keys, descriptions and illustrations are provided for the 18 recognized North American species.
Indices of atmospheric purity and fluoride pollution pattern in Arvida, Quebec
Authors: LeBlanc Fabius , Rao Dhruva N. , Comeau Gilberte
Published: June 2008

Indices of atmospheric purity (IAP) of 42 sites located in all directions from the aluminum factory at Arvida and spread out in about 250-km2 area, were determined on the basis of phytosociology of epiphytes of Populus balsamifera. These index values ranging from 0 to 103 were arranged into six groups and the investigated area was accordingly delineated into six IAP zones to represent areas with different levels of fluoride pollution. A relative picture of the approximate limits of fluoride contamination in different zones is obtained by the fluoride accumulation in Parmelia sulcata thalli transplanted at various sites in the area.
Morphology of Warcupia terrestris, a new ascomycete genus and species from soil
Authors: Paden John W. , Cameron Judith V.
Published: June 2008

Warcupia terrestris gen. et sp. nov. is described from soil from Victoria, British Columbia, Canada. The ascocarp is a globose, brown cleistothecium. The asci are unitunicate, eight-spored, cylindrical to broadly clavate, and deliquesce slowly. The ascospores are smooth, hyaline, ellipsoid, two- or three-guttulate, and lack a germ pore. Paraphyses are present during development and at maturity. There is no conidial state.The ascocarp is initiated by a coiled hypha that becomes a multicelled ascogonium. This is soon surrounded by sterile hyphae that form the wall of the developing ascocarp. In section, paraphyses with free apices are evident at a very early stage of development. Young asci appear shortly thereafter and arise from the entire inner wall of the ascocarp. At maturity the centrum contains a mass of spores, paraphyses, and deliquescing asci.
Morphological and histological studies of the effects of sodium cyclamate on Haworthia callus in vitro
Authors: Majumdar S. K. , Schlosser S. A.
Published: June 2008

Haworthia variegata callus grew and differentiated normally and produced many plantlets in the control medium containing 2 to 3% sucrose. This medium stimulated cell division, vascularization, and primordia formation as evidenced by histological studies. The growth of the callus on 1% cyclamate with or without 2% sucrose media was inhibited to such an extent that the explants produced only a few nodules and plantlets, and further development was not observed. Similarly, the occurrence of cell division, vascularization, and production of primordial initials was reduced to a minimum. On 3% cyclamate with or without 2% sucrose media, the callus growth was completely inhibited and the explants began to shrivel up 8–10 weeks after inoculation and died. Neither the vascular tissues nor the primordial initials were seen in the explant sections and the cells were distorted and ragged. However, sodium cyclamate did not induce chromosomal damage in Haworthia cells.
Chemosystematic studies in the genus Pseudotsuga. I. Leaf oil analysis of the coastal and Rocky Mountain varieties of the Douglas fir
Authors: Rudloff E. von
Published: June 2008

The volatile leaf oils of the coastal and Rocky Mountain varieties of the Douglas fir were found to have distinctive terpene compositions. The relative amounts of l-β-pinene, sabinene, 3-carene, α- and γ-terpinene, terpinolene, l-terpinen-4-ol, citronellol, citronellyl and geranyl acetate (relatively large in the former variety); and santene, tricyclene, l-camphene, limonene, and l-bornyl acetate (relatively large in the latter variety) may serve as distinguishing features. n-Hexenal, l-α-pinene, α- and β-phellandrene, linalool, fenchyl alcohol, and l-α-terpineol were also isolated. The within-tree and within-population variation of the amounts of these terpenes as well as populational differences from Calgary through the foothills to Revelstoke were small. Intermediate compositions were encountered as far west as the Cascades and one may distinguish clearly between interior and coastal intermediate terpene patterns. Between Keremeos and Hedley the terpene pattern was essentially that of the Rocky Mountain variety whereas at Jasper intermediate patterns leaning towards coastal intermediates were recorded. Analysis of the leaf oils from five different provenances of coastal populations indicated that a north–south cline may exist. Provenance samples showed conclusively that the terpene patterns are genetically controlled and are not influenced by ecological factors. Hence these terpene patterns may serve as a genetic guide and provide a quantitative measure of coastal, intermediate, and Rocky Mountain types of populations.
Estimation of the rates of mass carbon transfer by leaves of sugar beet
Authors: Terry Norman , Mortimer D. C.
Published: June 2008

Estimates of the rate of translocation of carbon, T, from sugar beet leaves were made from simultaneous determinations of CO2 exchange and dry weight change. For an illuminated leaf in a constant environment, T increased to a maximum during the first 2 h and was constant for the next 10 h. On darkening, T decreased rapidly in the first 2 to 4 h to a constant minimal value which could continue for as long as 24 h. The average value of T for nine leaves in the light was 4.2 ± 0.4 mg C dm−2 leaf surface h−1, while in the dark the average value for five leaves over 10 h was 1.2 ± 0.2 mg C dm−2 h−1. Generally T was about three-quarters of the net rate of photosynthetic carbon fixation.
Effects of secondary fungi on the epidemiology of western gall rust
Authors: Byler J. W. , Cobb Jr. F. W. , Parmeter Jr. J. R.
Published: June 2008

Results of rust gall (Peridermium harknessii) population studies, made in five coastal California stands, substantiate earlier reports of gall mortality. Evidence suggests that secondary fungi and insects were responsible for this mortality and not the rust alone. Nectria fuckeliana was the most aggressive secondary fungus encountered and was present on most of the dead and damaged galls in those locations where gall mortality was greatest. The results suggest that secondary organisms are important in controlling rust populations in these locations.
The occurrence and pathogenicity of Nectria fuckeliana on dwarf mistletoe in California
Authors: Byler J. W. , Cobb Jr. F. W.
Published: June 2008

Cylindrocarpon sporodochia were observed on dwarf mistletoe swellings on both Bishop pine and white fir. Evidence suggests that the fungus is Nectria fuckeliana and that this secondary pathogen of Peridermium harknessii galls is pathogenic on dwarf-mistletoe-infected tissues.
A new nothospecies of moonwort (Ophioglossaceae, Botrychium)
Authors: Wagner Jr. W. H. , Wagner Florence S. , Haufler Christopher , Emerson Jean K.
Published: June 2008

A new nothospecies of moonwort (Botrychium subg. Botrychium) is reported from Waterton Lakes National Park, Alta., Canada, where it is associated with its putative parents, B. paradoxum W. Wagner and B. hesperium (Maxon and Clausen) Wagner and Lellinger. A population of 29 individuals of the hybrid was found. The plant is here named and described as B. × watertonense W. Wagner nothosp. nov. Morphologically it is remarkable for displaying leaf characteristics intermediate between B. paradoxum, which has two sporophores but no sterile lamina, and the more typical B. hesperium with a single sporophore plus a sterile lamina. The "sterile lamina" of B. ×watertonense is much contracted, has simple venation, and produces sporangia along the margins from base to apex. Flavonoid chemical constituents of the nothospecies compared with its putative parents corroborate the conclusion of its hybrid origin based on occurrence and morphology. The presence of so many individuals at the type locality of a presumably sterile nothospecies is surprising in view of the fact that vegetative propagation is unknown in this genus. In spite of their obvious abortion, there may be some mode of reproduction by spores.
The effects of salicylates on phenomena related to crown gall
Authors: Saint-Pierre B. , Miville L. , Dion P.
Published: June 2008

The effects of acetylsalicylate and salicylate were investigated on three phenomena involved in crown-gall disease. First, an inhibition of the growth of Agrobacterium tumefaciens was observed with low concentrations of salicylates. This inhibition was pH dependent and was partially reversed by glutamate. Second, an inhibition of the growth of tobacco tumor tissue was observed only at high concentrations of salicylates. Third, tumor formation on excised tobacco leaves was inhibited by low concentrations of salicylates. The inhibition of tumor formation occurred at salicylate concentrations that had no significant effect on the net rate of photosynthesis by the leaves. The inhibition of tumor formation was also observed with a mutant strain of A. tumefaciens resistant to salicylate. The potential interest of salicylates as control agents for crown-gall disease is discussed.
The role of vesicular–arbuscular mycorrhizal fungi in the growth of Kansas winter wheat
Authors: Hetrick B. A. Daniels , Bockus W. W. , Bloom J.
Published: June 2008

In field experiments, fall-planted hard red winter wheat plants failed to become mycorrhizal until May or June just prior to harvest. No benefit to yield was evident from this late-season colonization, and in-furrow infestation with Glomus mosseae or Glomus epigaeum failed to provide earlier colonization or any increased yield. Neither were these mycorrhizal fungi successful in reducing the soil-borne diseases Cephalosporium stripe and take-all in the field. All eight wheat cultivars tested became mycorrhizal under greenhouse conditions whether nonsterile field soil was amended or not with a vesicular–arbuscular (VAM) fungus. Volunteer wheat plants collected from the field during summer also showed some limited level of colonization. Plants grown at 10 °C failed to be colonized, but plants grown at 25 °C were mycorrhizal after 10 weeks. Therefore, the observed failure of winter wheat in the field to become mycorrhizal until late in the growing season could not be explained by cultivar resistance or insufficient inoculum levels in field soils but may be attributed to low fall soil temperatures which may inhibit spore germination or root colonization. Thus, under field conditions it appears that mycorrhizal fungi have little or no effect on winter wheat in Kansas, but the isolation of cold-tolerant, highly efficient isolates should be pursued.
Occurrence and distribution of cones borne laterally on long shoots of Larix laricina
Authors: Powell G. R. , Tosh Kathleen J. , Remphrey W. R.
Published: June 2008

Trees of Larix laricina (Du Roi) K. Koch reaching the stage of first cone bearing tended to produce the majority of their seed cones, and many of their pollen cones, in lateral (axillary) positions along long shoots. In subsequent cone bearing, a greater proportion of the cones occurred in the typical (for the genus) position terminating short shoots. Some trees 2 to 4 m tall bore over 500 lateral seed cones. Lateral cones occurred on all kinds of long shoots, except sylleptic first-order shoots, produced in the 3-year-old portion of the crown. Lateral seed cones were borne on the morphogenically proximal halves of the long shoots and on all surfaces around the circumference of the shoots, but they were less frequent on upper surfaces than on other surfaces. Lateral pollen cones occurred in the proximal 10% of the lengths of the bearing shoots and were restricted to the undersurfaces or sides of the shoots. Lateral cone buds were distinctively larger and contained more bud scales than adjacent lateral short-shoot buds.
The relative efficiency of cytokinins in the development of normal spikelets on cultured tassels of Zea mays
Authors: Polowick P. L. , Greyson R. I.
Published: June 2008

Tassels of Zea mays L. (cv. Seneca-60) cultured in a defined liquid medium, produce normal spikelets, especially in the presence of cytokinins. Kinetin and benzylaminopurine (BAP) are the most efficient cytokinins, both in terms of the frequency with which tassels produce normal spikelets and in the number of such spikelets per tassel. Zeatin, zeatin riboside, and 6-(γ,γ-dimethylallylamino)-purine (2iP) are less effective. Other common and individual responses to the cytokinins are noted.
Studies of the holoparasite Tristerix aphyllus (Loranthaceae) infecting Trichocereus chilensis (Cactaceae)
Authors: Mauseth James D. , Montenegro Gloria , Walckowiak Alan M.
Published: June 2008

Many of the large columnar cacti Trichocereus chilensis near Santiago are infected by Tristerix aphyllus. This is one of the most highly reduced seed plants known: as it is an endoparasite, inflorescences are the only parts of the plant ever to emerge from the host, all the rest exists as an endophytic haustorial system; roots, vegetative stems, and leaves are not produced. After infection, the parasite spreads through the thick cortex of the host, reaching the vascular cambium and conducting tissues. It continues to grow intrusively throughout all tissues of the host shoot. In its invasive stage it occurs as a "myceliumlike" mass of uniseriate filaments that grow between host cells but only rarely enter them. Later growth is by longitudinal cell division that produces irregular parenchymatous strands. Eventually, xylem and phloem differentiate in the endophytic strands; the phloem is like that of other seed plants, but the xylem is almost pure parenchyma, with only occasional, idioblastic tracheary elements. Strands close to the epidermis of the host are able to produce adventitious flower buds that emerge through either soft regions in the epidermis (the areoles) or through accidental breaks in it. The flower stalk may persist, forming a small perennial inflorescence that has well-developed xylem, phloem, and periderm but is without leaves. Host cells appear healthy and normal, with no sign of damage caused by the presence of the parasite.
Habitat relationships of Chamaecyparis nootkatensis in southern Washington, Oregon, and California
Authors: Antos Joseph A. , Zobel Donald B.
Published: June 2008

Chamaecyparis nootkatensis is uncommon south of Mount Rainier, Washington. It occurs almost exclusively above 1100 m elevation and occasionally reaches timberline. Populations are generally adjacent to open habitats such as meadows, rocky ridges, avalanche tracks, bogs, and lakeshores. The species rarely grows in extensive tracts of closed-canopy forest. In 75 sample plots, 387 vascular species occurred, including indicators of both very wet and dry environments. Judging from the accompanying flora, the topographic locations occupied, and water potential data, C. nootkatensis can grow throughout much of the range of moisture conditions present at high elevations in the Cascade Mountains from central Oregon north. Chamaecyparis nootkatensis varies in growth form from a shrub to a tree 50 m tall. Layering produced the majority of small stems on most sites; it facilitates expansion both on open sites and of shrub-form plants in the forest. Chamaecyparis nootkatensis establishes some seedlings and is shade tolerant enough to survive under moderately dense canopies, but forest-grown seedlings fail to develop a strong upright trunk. Most trees on forest sites appear to have established following disturbance.
Architecture and development of the phyllode–stipule whorls of Acacia longipedunculata: controversial interpretations and continuum approach
Authors: Rutishauser Rolf , Sattler Rolf
Published: June 2008

The whorls of Acacia longipedunculata consist of 15–27 terete phyllodes and as many setaceous stipules. Their four most surprising features are as follows. (i) Only five to eight traces leave the stele within a whorl node; branches of these supply all appendages (phyllodes, stipules), (ii) The development of a new whorl starts with a polygonal bulge around the shoot apex. On this girdling primordium all whorl appendages are initiated centrifugally. (iii) Occasionally there are intermediates between phyllodes and stipules. (iv) The seedlings change from spiral to whorled phyllotaxis, with fascicles that fit into the generative helix. Four perspectives are proposed to interpret the phyllode–stipule whorls morphologically, based on different sets of assumptions such as the relative value of early developmental events as opposed to vascular patterns. All of these interpretations approximate nature to some degree, but in all probability none of them reflects nature fully. As the most adequate interpretation we propose a heterogeneous continuum in which pinnate juvenile leaves, phyllodes, stipules, and even clubshaped multiseriate hairs (inside and between the phyllodes) are parts of a morphocline linked by rare intermediates. A corollary of this interpretation is that stipules need not necessarily be considered as subunits of leaves. Such a modified leaf–stipule concept seems to be appropriate for various angiospermous taxa, especially Leguminosae, Rubiaceae, and Cunoniaceae. The whorl architecture of Acacia longipedunculata is compared with that of various other acacias (e.g., A. verticillata) and other taxa of angiosperms. Pertinent botanical and philosophical terms are explained in a detailed glossary.
Effect of supplemental NO3 on plant growth and components of photosynthetic carbon metabolism in soybean (Glycine max)
Authors: Kerr Phillip S. , Israel Daniel W. , Huber Steven C. , Rufty Jr. Thomas W.
Published: June 2008

The effect of supplied N (5, 10, or 20 mM[Formula: see text]) on plant growth and components of photosynthetic carbon metabolism was determined in soybean plants (Glycine max (L.) Merr. cv. Ransom) inoculated with Rhizobium japonicum strain USDA 110. The N treatments were started at 14 days after transplanting and plants were sampled at 10, 17, 23 and 43 days after initiation of the treatments. Total dry weight, shoot/root ratio and mean relative growth rate all increased one- to two-fold in response to supplied N. Carbon dioxide exchange rate, assimilate export rate, sucrose phosphate synthase activity, leaf sucrose concentration and leaf starch mobilization increased in response to supplied N at the first two sample dates, whereas starch accumulation rate was affected to a lesser degree. The response of these parameters to supplied N was diminished at the later two sample dates. Plant age and partial alleviation of the nitrogen stress that occurred during early nodule development were factors associated with the decreased treatment response at the later sampling dates. Assimilate export rate was correlated positively with carbon exchange rate (r = 0.84), sucrose phosphate synthase activity (r = 0.71) and leaf sucrose concentration (r = 0.83). This suggested that the enzymatic capacity for sucrose formation as well as net carbon fixation and leaf sucrose concentration are related to the rate of assimilate export. The results illustrated the interdependence of photosynthetic carbon metabolism and N nutrition and emphasized that certain photosynthetic components are more sensitive to changes in N nutrition than others.
Histochemistry of the dormant vascular cambium of Abies balsamea: changes associated with tree age and crown position
Authors: Riding R. T. , Little C. H. A.
Published: June 2008

On three dates during September–December, the histochemistry and dormancy status of cambial zone cells were investigated in 6- and 19-year-old balsam fir (Abies balsamea) trees at the top of the crown (1-year-old cambium) and near the base of the bole (5- and 13-year-old cambium, respectively). The extent of dormancy on the date of collection and after 4 weeks in controlled-environment conditions favorable for growth indicated that a changeover between the dormancy stages of rest and quiescence occurred in all ages of the cambium during the experimental period. In trees of both ages, cambial dormancy began later, and the number of fusiform cells in the cambial zone was greater at the bottom of the tree than at the top. The staining intensities for total cytoplasmic RNA, protein, and insoluble carbohydrates in the fusiform cambial zone cells increased during the rest–quiescence transition at the top and bottom of the 6-year-old trees and at the top of the 19-year-old trees. However, no significant increase in RNA staining occurred at the bottom of the 19-year-old trees.
Taxonomy of glandular wild alfalfa (Medicago sativa)
Authors: Small Ernest
Published: June 2008

Yellow-flowered plants of Medicago sativa L. sensu lato with coiled pods covered with glandular trichomes are treated as M. sativa subsp. glomerata (Balbis) Rouy, and those with yellow flowers and uncoiled glandular pods as M. sativa subsp. falcata (L.) Arcangeli var. viscosa (Reichenb.) Posp. Synonymy of these and common hybrid forms is given.
EFFECTS OF THERMAL ENVIRONMENTS ON THE THERMAL SHOCK RESISTANCE OF ULTRA-HIGH TEMPERATURE CERAMICS
Authors: LI WEIGUO , FANG DAINING
Published: June 2008

In the present study, the temperature-dependent thermal shock resistance parameter of Ultra-High Temperature Ceramics (UHTCs) was measured based on the current evaluation theories of thermal shock resistance parameters, since the material parameters of UHTCs are very sensitive to the changes of temperature. The influence of some important thermal environment parameters on the thermal shock resistance and critical temperature difference of rupture of UHTCs were studied. By establishing the relation between the temperature and the thermal or mechanical properties of the UHTCs, we found that thermal shock behavior of UHTCs is strongly affected by the surface heat transfer coefficient, heat transfer condition and initial temperature of the thermal shock.
SUPERCONDUCTIVITY IN Ru-BASED CUPRATE Ru(Sr1.5Ca0.5)PbCu2O8 PREPARED BY SOL–GEL ROUTE
Authors: YEOH L. M. , AHMAD M. , ABD-SHUKOR R.
Published: June 2008

Pb containing ruthenium-based superconducting cuprates Ru ( Sr 1.5 Ca 0.5) PbCu 2 O 8 ( Ru -1212 type) have been successfully synthesized through the sol–gel route. The optimum annealing temperature for the ruthenium-based cuprate superconductor was found to be 890°C. The crystal structure determined by X-ray powder diffraction method showed a single Ru -1212 type phase with tetragonal symmetry with lattice parameters a = b = 3.920 Å, and c = 11.76 Å. The Ru ( Sr 1.5 Ca 0.5) PbCu 2 O 8 material showed onset temperature, Tc -onset at 35 K and zero resistant temperature, Tc -zero at 20 K. Pb together with the partial substitution of Sr with Ca lowered the formation temperature of the Ru -1212 type phase.
TRIANGULAR FORM OF CHAOTIC SYSTEM AND ITS APPLICATION IN CHAOS SYNCHRONIZATION
Authors: WANG XING-YUAN , GU NI-NI , ZHANG ZHEN-FENG
Published: June 2008

The triangular form of a chaotic system and how to obtain it from the Lie derivative are introduced. Based on this, both the synchronization of Genesio–Tesi and Coullet systems and the generalized synchronization of Lü and Sprott-B systems are realized in two feedback ways through designing nonlinear controllers. Results of numerical simulations in MATLAB validate the effectiveness of the given synchronization methods further.
BOUNDED-VELOCITY APPROXIMATION OF MOBILE EUCLIDEAN 2-CENTRES
Authors: DUROCHER STEPHANE , KIRKPATRICK DAVID
Published: June 2008

Given a set P of points (clients) in the plane, a Euclidean 2-centre of P is a set of two points (facilities) in the plane such that the maximum distance from any client to its nearest facility is minimized. Geometrically, a Euclidean 2-centre of P corresponds to a cover of P by two discs of minimum radius r (the Euclidean 2-radius). Given a set of mobile clients, where each client follows a continuous trajectory in the plane with bounded velocity, the motion of the corresponding mobile Euclidean 2-centre is not necessarily continuous. Consequently, we consider strategies for defining the trajectories of a pair of mobile facilities that guarantee a fixed-degree approximation of the Euclidean 2-centre while maintaining bounded relative velocity. In an attempt to balance the conflicting goals of closeness of approximation and a low maximum relative velocity, we introduce reflection-based 2-centre functions by reflecting the position of a mobile client across the mobile Steiner centre and the mobile rectilinear 1-centre, respectively.
EXPERIMENTAL EVALUATION OF DYNAMIC BEHAVIOR OF PIPELINE SYSTEMS OF THERMAL POWER PLANTS EXPOSED TO SEISMIC LOADS
Authors: TASKOV LJUBOMIR , KRSTEVSKA LIDIJA , TEMELKOSKA BRATICA
Published: June 2008

This paper deals with the experimental results obtained by in situ and model testing of a segment of the pipeline system of a thermal power plant. The field testing has been performed by using the forced and ambient vibration method. The model testing has been performed by means of a shaking table. The model was designed and constructed to the scale of 1/3 and tested on the seismic shaking table in the IZIIS' laboratory. The adopted modeling concept was an adequate model with artificial mass simulation, using the same material as that of the prototype. The spring hangings, as well as the special rolling support, have also been simulated. The model was subjected to random, harmonic and earthquake motion in horizontal, vertical and biaxial directions. The results show that the support springs can accept displacements in both the horizontal and the vertical direction in the elastic range of deformation, while the stop point base support is sensitive to the intensity of earthquake motion and is required to be limited to the horizontal and vertical directions.
ANALYTIC ONE-BIT AND CNOT GATE CONSTRUCTIONS OF GENERAL n-QUBIT CONTROLLED GATES
Authors: LIU YANG , LONG GUI LU , SUN YANG
Published: June 2008

General n-qubit controlled unitary gates are frequently used in quantum information processing tasks. Barenco, Bennett, Cleve, Di Vincenzo, Margolus and Shor [Phys. Rev. A52 (1995) 3457] have given the general construction methods, and explicit results for up-to-four-qubits controlled unitary gates. We extended their calculation and gave two analytic expressions for the construction of general n-qubit controlled unitary gates in terms of one-qubit and two-qubit CNOT gates. There are two expressions – one is exponential in the qubit number which is efficient for up to ten qubits, and the other is polynomial in the qubit number, which is efficient for more than ten qubits.
PERFECT CONTROLLED QUANTUM SECURE DIRECT COMMUNICATION
Authors: XIA YAN , SONG JIE , SONG HE-SHAN
Published: June 2008

We present a complete controlled quantum secure direct communication (CQSDC) protocol using a nonsymmetric quantum channel. We point out that the roles of controllers in two recent works16,17 can be excluded due to their design. We also give a revised CQSDC protocol such that their original advantages are retained and the complete CQSDC can be realized. We then analyze the roles of the controllers in different CQSDC protocols with different purposes and these protocols' applicabilities.
Resistance exercise decreases eIF2Bε phosphorylation and potentiates the feeding-induced stimulation of p70S6K1 and rpS6 in young men
Authors: Glover Elisa I. , Oates Bryan R. , Tang Jason E. , Moore Daniel R. , Tarnopolsky Mark A. , Phillips Stuart M.
Published: June 2008

We investigated the effect of resistance exercise and feeding on the activation of signaling proteins involved in translation initiation. Nine young men (23.7 ± 0.41 yr; BMI = 25.5 ± 1.0 kg/m2; means ± SE) were tested twice after they performed a strenuous bout of unilateral resistance exercise, such that their contralateral leg acted as a nonexercised comparator, in either the fasted and fed [1,000 kJ, each 90 min (3 doses): 10 g protein, 41 g carbohydrate, 4 g fat] states. Muscle biopsies were obtained 6 h postexercise from both legs, resulting in four experimental conditions: rest-fasted, rest-fed, exercise-fasted, and exercise-fed. Feeding increased PKB/Akt (Ser473) phosphorylation ( P < 0.05), while exercise increased the phosphorylation of Akt and the downstream 70 kDa S6 protein kinase (p70S6K1, Thr389) and ribosomal protein S6 (rpS6, Ser235/236, Ser240/244; all P < 0.05). The combination of resistance exercise and feeding increased the phosphorylation of p70S6K1 (Thr389) and rpS6 (Ser240/244) above exercise alone ( P < 0.05). Exercise also reduced phosphorylation of the catalytic epsilon subunit of eukaryotic initiation factor 2B (eIF2Bε, Ser540; P < 0.05). Mammalian target of rapamycin (mTOR, Ser2448), glycogen synthase kinase-3β (GSK-3β, Ser9), and focal adhesion kinase (FAK, Tyr576/577) phosphorylation were unaffected by either feeding or resistance exercise (all P > 0.14). In summary, feeding resulted in phosphorylation of Akt, while resistance exercise stimulated phosphorylation of Akt, p70S6K1, rpS6, and dephosphorylation eIF2Bε with a synergistic effect of feeding and exercise on p70S6K1 and its downstream target rpS6. We conclude that resistance exercise potentiates the effect of feeding on the phosphorylation and presumably activation of critical proteins involved in the regulation of muscle protein synthesis in young men.
Cardiac norepinephrine transporter protein expression is inversely correlated to chamber norepinephrine content
Authors: Wehrwein Erica A. , Parker Lindsay M. , Wright Anna A. , Spitsbergen John M. , Novotny Martin , Babankova Dagmar , Swain Greg M. , Habecker Beth A. , Kreulen David L.
Published: June 2008

The cardiac neuronal norepinephrine (NE) transporter (NET) in sympathetic neurons is responsible for uptake of released NE from the neuroeffector junction. The purpose of this study was to assess the chamber distribution of cardiac NET protein measured using [3H]nisoxetine binding in rat heart membranes and to correlate NE content to NET amount. In whole mounts of atria, NET was colocalized in nerve fibers with tyrosine hydroxylase (TH) immunoreactivity. NE content expressed as micrograms NE per gram tissue was lowest in the ventricles; however, NET binding was significantly higher in the left ventricle than the right ventricle and atria ( P < 0.05), resulting in a significant negative correlation ( r2 = 0.922; P < 0.05) of NET to NE content. The neurotoxin 6-hydroxydopamine, an NET substrate, reduced NE content more in the ventricles than the atria, demonstrating functional significance of high ventricular NET binding. In summary, there is a ventricular predominance of NET binding that corresponds to a high NE reuptake capacity in the ventricles, yet negatively correlates to tissue NE content.
Mechanisms underlying angiotensin II-induced calcium oscillations
Authors: Edwards Aurélie , Pallone Thomas L.
Published: June 2008

To gain insight into the mechanisms that underlie angiotensin II (ANG II)-induced cytoplasmic Ca2+concentration ([Ca]cyt) oscillations in medullary pericytes, we expanded a prior model of ion fluxes. ANG II stimulation was simulated by doubling maximal inositol trisphosphate (IP3) production and imposing a 90% blockade of K+channels. We investigated two configurations, one in which ryanodine receptors (RyR) and IP3receptors (IP3R) occupy a common store and a second in which they reside on separate stores. Our results suggest that Ca2+release from stores and import from the extracellular space are key determinants of oscillations because both raise [Ca] in subplasmalemmal spaces near RyR. When the Ca2+-induced Ca2+release (CICR) threshold of RyR is exceeded, the ensuing Ca2+release is limited by Ca2+reuptake into stores and export across the plasmalemma. If sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) pumps do not remain saturated and sarcoplasmic reticulum Ca2+stores are replenished, that phase is followed by a resumption of leak from internal stores that leads either to [Ca]cytelevation below the CICR threshold (no oscillations) or to elevation above it (oscillations). Our model predicts that oscillations are more prone to occur when IP3R and RyR stores are separate because, in that case, Ca2+released by RyR during CICR can enhance filling of adjacent IP3stores to favor a high subsequent leak that generates further CICR events. Moreover, the existence or absence of oscillations depends on the set points of several parameters, so that biological variation might well explain the presence or absence of oscillations in individual pericytes.
Ornithine decarboxylase inhibitor eliminates hyperresponsiveness of the early diabetic proximal tubule to dietary salt
Authors: Miracle Cynthia M. , Rieg Timo , Mansoury Hadi , Vallon Volker , Thomson Scott C.
Published: June 2008

Heightened sensitivity of the diabetic proximal tubule to dietary salt leads to a paradoxical effect of salt on glomerular filtration rate (GFR) via tubuloglomerular feedback. Diabetic hyperfiltration is a feedback response to growth and hyperreabsorption by the proximal tubule. The present studies were performed to determine whether growth and hyperfunction of the proximal tubule are essential for its hyperresponsiveness to dietary salt and, hence, to the paradoxical effect of dietary salt on GFR. Micropuncture was performed in four groups of inactin-anesthetized Wistar rats after 10 days of streptozotocin diabetes drinking tap water or 1% NaCl. Kidney growth was suppressed with ornithine decarboxylase (ODC) inhibitor, DFMO (200 mg·kg−1·day−1), or placebo. Single nephron GFR (SNGFR) was manipulated by perfusing Henle's loop so that proximal reabsorption ( Jprox) could be expressed as a function of SNGFR in each nephron, dissociating primary effects on the tubule from the effects of glomerulotubular balance. Alone, DFMO or high salt reduced SNGFR and suppressed Jproxindependent of SNGFR. Suppression of Jproxwas eliminated and SNGFR increased when high salt was given to rats receiving DFMO. ODC is necessary for hyperresponsiveness of the proximal tubule to dietary salt and for the paradoxical effect of dietary salt on GFR in early diabetes. This coupling of effects adds to the body of evidence that feedback from the proximal tubule is the principal governor of glomerular filtration in early diabetes.
Effects of estrogen on the mechanical behavior of the human Achilles tendon in vivo
Authors: Bryant Adam L. , Clark Ross A. , Bartold Simon , Murphy Aron , Bennell Kim L. , Hohmann Erik , Marshall-Gradisnik Sonya , Payne Craig , Crossley Kay M.
Published: June 2008

The purpose of this study was to elucidate the effect of normal fluctuating [non-monophasic oral contraceptive pill (MOCP) users] and low, consistent (MOCP users) endogenous plasma estrogen levels on the strain behavior of the Achilles tendon in vivo. Twenty women (age 28.0 ± 4.2 yr, height 1.67 ± 0.07 m, mass 61.6 ± 6.8 kg) who had been using the MOCP for at least 12 mo together with 20 matched women who were non-MOCP users (age 31.9 ± 7.3 yr, height 1.63 ± 0.05 m, mass 62.5 ± 5.9 kg) participated in this study. Non-MOCP users were tested at the time of lowest (menstruation) and highest (≈ovulation) estrogen, whereas MOCP users, who exhibited constant and attenuated endogenous estrogen levels, were tested at day 1 and day 14 of their cycle. At each test session, maximal isometric plantarflexion efforts were performed on a calf-raise apparatus while synchronous real-time ultrasonography of the triceps surae aponeurosis was recorded. Achilles tendon strain (%) was calculated by dividing tendon displacement during plantarflexion by resting tendon length. Repeated-measures ANOVA revealed a significant ( P < 0.05) main effect of subject group with significantly lower Achilles strain (25.5%) in the MOCP users compared with the non-MOCP users. In conclusion, acute fluctuations in plasma estrogen across the menstrual cycle in non-MOCP users did not alter the strain behavior of the Achilles tendon. Conversely, long-term exposure to attenuated estrogen in MOCP users resulted in a decrease in Achilles tendon strain, which is thought to be attributed to the effects of endogenous estrogen on collagen synthesis. These findings have a number of important functional and clinical implications.
Glycine Receptors Mediate Excitation of Subplate Neurons in Neonatal Rat Cerebral Cortex
Authors: Kilb W. , Hanganu I. L. , Okabe A. , Sava B. A. , Shimizu-Okabe C. , Fukuda A. , Luhmann H. J.
Published: June 2008

The development of the cerebral cortex depends on genetic factors and early electrical activity patterns that form immature neuronal networks. Subplate neurons (SPn) are involved in the construction of thalamocortical innervation, generation of oscillatory network activity, and in the proper formation of the cortical columnar architecture. Because glycine receptors play an important role during early corticogenesis, we analyzed the functional consequences of glycine receptor activation in visually identified SPn in neocortical slices from postnatal day 0 (P0) to P4 rats using whole cell and perforated patch-clamp recordings. In all SPn the glycinergic agonists glycine, β-alanine, and taurine induced dose-dependent inward currents with the affinity for glycine being higher than that for β-alanine and taurine. Glycine-induced responses were blocked by the glycinergic antagonist strychnine, but were unaffected by either the GABAergic antagonist gabazine, the N-methyl-d-aspartate–receptor antagonist d-2-amino-5-phosphonopentanoic acid, or picrotoxin and cyanotriphenylborate, antagonists of α-homomeric and α1-subunit–containing glycine receptors, respectively. Under perforated-patch conditions, glycine induced membrane depolarizations that were sufficient to trigger action potentials (APs) in most cells. Furthermore, glycine and taurine decreased the injection currents as well as the synaptic stimulation strength required to elicit APs, indicating that glycine receptors have a consistent excitatory effect on SPn. Inhibition of taurine transport and application of hypoosmolar solutions induced strychnine-sensitive inward currents, suggesting that taurine can act as a possible endogenous agonist on SPn. In summary, these results demonstrate that SPn express glycine receptors that mediate robust excitatory membrane responses during early postnatal development.
Speed–Curvature Relations in Speech Production Challenge the 1/3 Power Law
Authors: Perrier Pascal , Fuchs Susanne
Published: June 2008

Relations between tangential velocity and trajectory curvature are analyzed for tongue movements during speech production in the framework of the 1/3 power law, discovered by Viviani and colleagues for arm movements. In 2004, Tasko and Westbury found for American English that the power function provides a good account of speech kinematics, but with an exponent that varies across articulators. The present work aims at broadening Tasko and Westbury's study 1) by analyzing speed–curvature relations for various languages (French, German, Mandarin) and for a biomechanical tongue model simulating speech gestures at various speaking rates and 2) by providing for each speaker or each simulated speaking rate a comparison of results found for the complete set of movements with those found for each movement separately. It is found that the 1/3 power law offers a fair description of the global speed–curvature relations for all speakers and all languages, when articulatory speech data are considered in their whole. This is also observed in the simulations, where the motor control model does not specify any kinematic property of the articulatory paths. However, the refined analysis for individual movements reveals numerous exceptions to this law: the velocity always decreases when curvature increases, but the slope in the log–log representation is variable. It is concluded that the speed–curvature relation is not controlled in speech movements and that it accounts only for general properties of the articulatory movements, which could arise from vocal tract dynamics or/and from stochastic characteristics of the measured signals.
Motor Unit Recruitment and Proprioceptive Feedback Decrease the Common Drive
Authors: De Luca Carlo J. , Gonzalez-Cueto Jose A. , Bonato Paolo , Adam Alexander
Published: June 2008

It has been documented that concurrently active motor units fire under the control of a common drive. That is, the firing rates show high correlation with near-zero time lag. This degree of correlation has been found to vary among muscles and among contractions performed at different force levels in the same muscle. This study provides an explanation indicating that motor units recruited during a contraction cause an increase in the variation (SD) and a decrease in the degree (amplitude) of the correlation of the firing rates. The degree of correlation is lower in muscles having greater spindle density. This effect appears to be mediated by the proprioceptive feedback from the spindles and possibly the Golgi tendon organs. Muscle spindles in particular respond to the mechanical excitation of the nonfused muscle fibers and provide a discordant excitation to the homonymous motoneurons, resulting in a decrease in the correlation of the firing rates of motor units. The implication of this work is that the decreased correlation of the firing rates in some muscles is not necessarily an indication of a decreased common drive from the CNS, but rather an inhibitory influence of the proprioceptive feedback from the peripheral nervous system. This explanation is useful for understanding various manifestations of the common drive reported in the literature.
Head Stabilization by Vestibulocollic Reflexes During Quadrupedal Locomotion in Monkey
Authors: Xiang Yongqing , Yakushin Sergei B. , Kunin Mikhail , Raphan Theodore , Cohen Bernard
Published: June 2008

Little is known about the three-dimensional characteristics of vestibulocollic reflexes during natural locomotion. Here we determined how well head stability is maintained by the angular and linear vestibulocollic reflexes (aVCR, lVCR) during quadrupedal locomotion in rhesus and cynomolgus monkeys. Animals walked on a treadmill at velocities of 0.4–1.25 m/s. Head rotations were represented by Euler angles (Fick convention). The head oscillated in yaw and roll at stride frequencies (≈1–2 Hz) and pitched at step frequencies (≈2–4 Hz). Head angular accelerations (100–2,500°/s2) were sufficient to have excited the aVOR to stabilize gaze. Pitch and roll head movements were <7°, peak to peak, and the amplitude was unrelated to stride frequency. Yaw movements were larger due to spontaneous voluntary head shifts and were smaller at higher walking velocities. Head translations were small (≤4 cm). Cynomolgus monkeys positioned their heads more forward in pitch than the rhesus monkeys. None of the animals maintained a forward head fixation point, indicating that the lVCR contributed little to compensatory head movements in these experiments. Significantly, aVCR gains in roll and pitch were close to unity and phases were ≈180° over the full frequency range of natural walking, which is in contrast to previous findings using anesthesia or passive trunk rotation with body restraint. We conclude that the behavioral state associated with active body motion is necessary to maintain head stability in pitch and roll over the full range of stride/step frequencies encountered during walking.
Coupling Specificity of NOP Opioid Receptors to Pertussis-Toxin-Sensitive Gα Proteins in Adult Rat Stellate Ganglion Neurons Using Small Interference RNA
Authors: Margas Wojciech , Sedeek Khaled , Ruiz-Velasco Victor
Published: June 2008

The opioid receptor-like 1 (NOP or ORL1) receptor is a G-protein-coupled receptor the endogenous ligand of which is the heptadecapeptide, nociceptin (Noc). NOP receptors are known to modulate pain processing at spinal, supraspinal, and peripheral levels. Previous work has demonstrated that NOP receptors inhibit N-type Ca2+channel currents in rat sympathetic stellate ganglion (SG) neurons via pertussis toxin (PTX)-sensitive Gαi/osubunits. However, the identification of the specific Gα subunit that mediates the Ca2+current modulation is unknown. The purpose of the present study was to examine coupling specificity of Noc-activated NOP receptors to N-type Ca2+channels in SG neurons. Small interference RNA (siRNA) transfection was employed to block the expression of PTX-sensitive Gα subunits. RT-PCR results showed that siRNA specifically decreased the expression of the intended Gα subunit. Evaluation of cell surface protein expression and Ca2+channel modulation were assessed by immunofluorescence staining and electrophysiological recordings, respectively. Furthermore, the presence of mRNA of the intended siRNA target Gα protein was examined by RT-PCR experiments. Fluorescence imaging showed that Gαi1, Gαi3, and Gαowere expressed in SG neurons. The transfection of Gαi1-specific siRNA resulted in a significant decrease in Noc-mediated Ca2+current inhibition, while silencing of either Gαi3or Gαowas without effect. Taken together, these results suggest that in SG neurons Gαi1subunits selectively couple NOP receptors to N-type Ca2+channels.