bluuebunny/crossref_metadata_2025 huggingface dataset:
The Phase Shift in the Jumping Ring
Authors: Jeffery Rondo N. , Amiri Farhang
Published: August 2008

The popular physics demonstration experiment known as Thomson's Jumping Ring (JR) has been variously explained as a simple example of Lenz's law, or as the result of a phase shift of the ring current relative to the induced emf. The failure of the first-quadrant Lenz's law explanation is shown by the time the ring takes to jump and by levitation. A method is given for measuring the phase shift with results for aluminum and brass rings.
An Inexpensive Toroidal Solenoid for an Investigative Student Lab
Authors: Ferstl Andrew , Broberg John
Published: August 2008

Magnetism and Ampère's law is a common subject in most calculus-based introductory physics courses. Many textbooks offer examples to calculate the magnetic field produced by a symmetric current by using Ampère's law.1 These examples include the solenoid and the toroidal solenoid (sometimes called a torus; see Fig. 1), which are used in many applications, including the study of plasmas.
Enhancement of Human Antigen-Specific Memory T-Cell Responses by Interleukin-7 May Improve Accuracy in Diagnosing Tuberculosis
Authors: Feske Marsha , Nudelman Rodolfo J. , Medina Miguel , Lew Justin , Singh Manisha , Couturier Jacob , Graviss Edward A. , Lewis Dorothy E.
Published: August 2008

Children and immunocompromised adults are at an increased risk of tuberculosis (TB), but diagnosis is more challenging. Recently developed gamma interferon (IFN-γ) release assays provide increased sensitivity and specificity for diagnosis of latent TB, but their use is not FDA approved in immunocompromised or pediatric populations. Both populations have reduced numbers of T cells, which are major producers of IFN-γ. Interleukin 7 (IL-7), a survival cytokine, stabilizes IFN-γ message and increases protein production. IL-7 was added to antigen-stimulated lymphocytes to improve IFN-γ responses as measured by enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunospot (ELISPOT) assay. Antigens used were tetanus toxoid (n= 10), p24 (from human immunodeficiency virus [HIV],n= 9), and TB peptides (n= 15). Keyhole limpet hemocyanin was used as a negative control, and phytohemagglutinin was the positive control. IL-7 improved antigen-specific responses to all antigens tested including tetanus toxoid, HIV type 1 p24, and TB peptides (ESAT-6 and CFP-10) with up to a 14-fold increase (mean = 3.8), as measured by ELISA. Increased IFN-γ responses from controls, HIV-positive patients, and TB patients were statistically significant, withPvalues of <0.05, 0.01, and 0.05, respectively. ELISPOT assay results confirmed ELISA findings (Pvalues of <0.01, 0.02, and 0.03, respectively), with a strong correlation between the two tests (R2= 0.82 to 0.99). Based on average background levels, IL-7 increased detection of IFN-γ by 39% compared to the level with antigen alone. Increased production of IFN-γ induced by IL-7 improves sensitivity of ELISA and ELISPOT assays for all antigens tested. Further enhancement of IFN-γ-based assays might improve TB diagnosis in those populations at highest risk for TB.
Assay for 5′ Noncoding Region Analysis of All Human Rhinovirus Prototype Strains
Authors: Kiang David , Kalra Ishmeet , Yagi Shigeo , Louie Janice K. , Boushey Homer , Boothby John , Schnurr David P.
Published: August 2008

Increasing recognition of the association of rhinovirus with severe lower respiratory tract illnesses has clarified the need to understand the relationship between specific serotypes of rhinovirus and their clinical consequences. To accomplish this, a specific and sensitive assay to detect and serotype rhinovirus directly from clinical specimens is needed. Traditional methods of serotyping using culture and serum neutralization are time-consuming, limited to certain reference laboratories, and complicated by the existence of over 100 serotypes of human rhinoviruses (HRVs). Accordingly, we have developed a sequence-based assay that targets a 390-bp fragment accounting for approximately two-thirds of the 5′ noncoding region (NCR). Our goal was to develop an assay permitting amplification of target sequences directly from clinical specimens and distinction among all 101 prototype strains of rhinoviruses. We determined the sequences of all 101 prototype strains of HRV in this region to enable differentiation of virus genotypes in both viral isolates and clinical specimens. We evaluated this assay in a total of 101 clinical viral isolates and 24 clinical specimens and compared our findings to genotyping results using a different region of the HRV genome (the VP4-VP2 region). Five specimens associated with severe respiratory disease in children did not correlate with any known serotype of rhinovirus and were found to belong to a novel genogroup of rhinovirus, genogroup C. Isolates were also found that corresponded to the genogroup A2 variant identified in New York and Australia and two other novel group A clusters (GAC1 and GAC2).
Engineered Intermonomeric Disulfide Bonds in the Globular Domain of Newcastle Disease Virus Hemagglutinin-Neuraminidase Protein: Implications for the Mechanism of Fusion Promotion
Authors: Mahon Paul J. , Mirza Anne M. , Musich Thomas A. , Iorio Ronald M.
Published: August 2008

The promotion of membrane fusion by Newcastle disease virus (NDV) requires an interaction between the viral hemagglutinin-neuraminidase (HN) and fusion (F) proteins, although the mechanism by which this interaction regulates fusion is not clear. The NDV HN protein exists as a tetramer composed of a pair of dimers. Based on X-ray crystallographic studies of the NDV HN globular domain (S. Crennell et al., Nat. Struct. Biol. 7:1068-1074, 2000), it was proposed that the protein undergoes a significant conformational change from an initial structure having minimal intermonomeric contacts to a structure with a much more extensive dimer interface. This conformational change was predicted to be integral to fusion promotion with the minimal interface form required to maintain F in its prefusion state until HN binds receptors. However, no evidence for such a conformational change exists for any other paramyxovirus attachment protein. To test the NDV model, we have engineered a pair of intermonomeric disulfide bonds across the dimer interface in the globular domain of an otherwise non-disulfide-linked NDV HN protein by the introduction of cysteine substitutions for residues T216 and D230. The disulfide-linked dimer is formed both intracellularly and in the absence of receptor binding and is efficiently expressed at the cell surface. The disulfide bonds preclude formation of the minimal interface form of the protein and yet enhance both receptor-binding activity at 37°C and fusion promotion. These results confirm that neither the minimal interface form of HN nor the proposed drastic conformational change in the protein is required for fusion.
T cell immunodeficiency
Authors: Edgar J D M
Published: August 2008

T cell immunodeficiency can occur as one of a group of primary disorders or develop secondary to chronic infection, illness or drug therapy. Primary T cell disorders are rare, accounting for approximately 11% of reported primary immunodeficiencies, and generally present in infancy or early childhood. Early recognition is very important as many of these patients will require bone marrow transplantation prior to the onset of severe infection or other complications. Because of their rarity, these infants usually present to clinicians who have little or no prior experience of these conditions, and therefore laboratory-based clinicians with knowledge of the key laboratory/pathological abnormalities and clinical features have a valuable role in identifying the possibility of immunodeficiency. Secondary T cell deficiency is a cardinal feature of HIV infection and the specific susceptibility to infectious micro-organisms is highlighted. The possibility of T cell immunodeficiency should be considered in any patient presenting with unusual or severe viral, fungal or protozoal infection.
THE INITIATION AND SPREAD OF PORIA WEIRII ROOT ROT OF DOUGLAS FIR
Authors: Wallis G. W. , Reynolds G.
Published: August 2008

Root rot caused by Poria weirii Murr. occurred when healthy roots of Douglas fir came into contact with inoculum in infected roots of the previous stand. Mycelium grew ectotrophically on the bark of the Douglas fir roots, frequently well in advance of growth in the wood, and penetrated to living tissues directly through sound as well as injured bark. Spread of the disease to adjacent trees took place where healthy and diseased roots were in contact, the mycelium apparently spreading to only a very limited extent through natural soil. It was shown that mycelium could invade roots of trees felled for at least 12 months and Douglas fir heartwood that had been buried in soil for at least 12 months. Viable Poria mycelium was isolated from infected roots as small as 2 cm in diameter 11 years after the trees had been cut. While Douglas fir and western hemlock appeared to be quite susceptible to infection, western red cedar, red alder, and bigleaf maple showed considerable resistance.
CHANGES IN THE LEAF AREA RATIO DURING GROWTH OF MARQUIS WHEAT, AS AFFECTED BY TEMPERATURE AND LIGHT INTENSITY
Authors: Friend D. J. C. , Helson V. A. , Fisher J. E.
Published: August 2008

The increase in the leaf area ratio during early growth and the later decrease were primarily caused by an initial increase in the growth of leaves relative to stems and roots and a later rapid increase in stem growth associated with flowering. Changes in leaf thickness with time had little effect on the leaf area ratio.Increasing temperature from 10 to 25 °C increased the leaf area ratio because the growth of leaves was promoted to a greater extent than the growth of stems and roots, and because leaves were thinner. A further increase in temperature to 30 °C lowered the leaf area ratio because of an increased proportion of stem and thicker leaves.Increasing light intensity from 200 to 2500 ft-c decreased the leaf area ratio because of an increase in the relative proportion of stem and root and increased leaf thickness.These effects of the environment were mostly independent of changes in the rate of development of the plant.
A NEW PARASITE OF SPRUCE FROM BRITISH COLUMBIA
Authors: Funk A.
Published: August 2008

Botryosphaeria piceae n. sp. is a parasite which causes perennial cankers of Picea sitchensis (Bong.) Carr. and P. engelmannii Parry in British Columbia. The affected branches may remain alive for many years. The fungus has been found only in the sexual state, producing ascospores chiefly in early spring.
THE BIOSYNTHESIS OF LONG-CHAIN FATTY ACIDS IN THE DEVELOPING CASTOR BEAN
Authors: Canvin D. T.
Published: August 2008

Acetate-1-C14and acetate-2-C14were supplied to slices of developing castor bean endosperm. The molecules were extensively incorporated into long-chain fatty acids, water-soluble compounds, and protein. Oleic acid was the fatty acid initially labelled from acetate and it was the precursor of ricinoleic acid. Aerobic conditions were required for the formation of oleic acid and for the conversion of oleic acid to ricinoleic acid. Under anaerobic conditions the incorporation of acetate carbon into fatty acids was inhibited more than 90% and almost all of the C14was found in stearic and palmitic acids. Stearic acid appeared to be formed first and palmitic acid appeared to be derived from it through a shortening of the chain. The position of linoleic acid in the fatty acid interconversions was not clear except that it was not a free intermediate in the conversion of oleic acid to ricinoleic acid.Malonate-C14was only absorbed slightly by the tissue and although absorption could be increased by the use of diethyl malonate the metabolism of the compound was not facilitated. Because of its poor utilization by the tissue the role of malonate in long-chain fatty acid synthesis in this tissue could not be ascertained.
INCORPORATION OF ACETATE-1-C14 INTO THE LONG-CHAIN FATTY ACIDS OF SOME OIL SEED CROPS
Authors: Canvin David T.
Published: August 2008

Acetate-1-C14 was supplied to developing seeds of flax, rape, and safflower in short term kinetic experiments. Oleic acid was the first long-chain fatty acid to become radioactive and it appeared to be the precursor of the other unsaturated fatty acids in these oil seeds. Stearic acid was unlabelled and palmitic acid appeared to be derived by a pathway independent of that leading to oleic acid.
INTERPRETATIONS OF THE CARBON DIOXIDE DEPENDENCE OF THE HILL REACTION
Authors: Good Norman E.
Published: August 2008

Heretofore Warburg's one-quantum theory of photosynthesis has seemed inconsistent with the existence of the Hill reaction. The one-quantum theory states that massive oxygen uptake and CO2release are preconditions of photosynthetic oxygen production, yet isolated chloroplasts produce oxygen at high rates apparently without consuming any oxygen or producing any CO2. Warburg has attempted to resolve the dilemma by pointing out a CO2dependence of the Hill reaction. On the basis of this observation he proposed a reinterpretation of the Hill reaction which is consistent with the one-quantum theory. The effect of CO2on isolated chloroplasts has been confirmed and some of the conditions which are necessary for the demonstration of the effect have been defined. It is not clear if CO2is actually metabolized as Warburg claims. Contrary to Warburg's model, its participation seems to be at a site remote from the photochemical act. A number of other reasons for doubting the reality of the one-quantum mechanism are presented.
THE GENUS GYMNOSPORANGIUM IN EASTERN CANADA
Authors: Parmelee J. A.
Published: August 2008

Nine species of Gymnosporangium native to Eastern Canada and one commonly intercepted on imported nursery stock, but not known to be established, are described, illustrated, and discussed. Species occurring in adjacent United States but unknown in Eastern Canada are briefly mentioned. G. connersii sp. nov. and Roestelia brucensis sp. nov. are newly described on Juniperus horizontalis. R. brucensis is noteworthy because it has a repeating aecial stage and lacks telia. This is the first example of repeating aecia occurring in the genus. Aecial and telial keys are presented, emphasizing characters that permit identification in the field. One such character is the date of aecial maturity; it is suggested that this is a ready means of verifying apparent differences in morphology between taxa in this genus.
GROWTH INHIBITION OF BACILLUS CEREUS IN VITRO BY GLYCOSIDAL SUBSTANCES EXTRACTED FROM BARK OF FRAXINUS
Authors: Jung Josef , Hubbes Martin
Published: August 2008

Bark extracts of Fraxinus pennsylvanica Marsh., F. americana L., F. nigra Marsh., and F. excelsior L. inhibited the growth of Bacillus cereus Frank. and Frank. in culture. Activity varied according to the sections of the stem and the species used. Extracts of F. pennsylvanica were most active. Thin-layer chromatograms and ultraviolet and infrared spectra of purified substances from bark extracts revealed two types of active compounds. On this basis the four species were separated in two taxonomically distinct groups which corresponded to the subsection of the genus Fraxinus proposed by Endlicher on morphological bases. The active compounds were identified as glycosides.
REVISION OF SOME DIMERIELLA AND DIMEROSPORIUM PARASITES OF CONIFERS
Authors: Shoemaker R. A.
Published: August 2008

Study of the type of Dimerosporium balsamicola (Peck) Ell. & Ev. (≡ Meliola balsamicola Peck) revealed that this species is a melioline hyperparasite. The fungus is transferred to Dimerium, redescribed, illustrated, and distinguished from Phacocryptopus nudus (Peck) Petrak, Asterina sp., and from Epipolaeum abietis (Dearness) n. comb. (≡ Dimerosporium abietis Dearness), which also occur on Abies in North America. In all, four species of Epipolaeum that occur on conifer needles are treated: Epipolaeum abietis on Abies grandis (Dougl.) Lindl. and Abies amabilis (Dougl.) Forb. in western North America, on Abies alba Mill. in France, and on Keteleeria davidiana Beiss. in Formosa; Epipolaeum tsugae (Dearness) n. comb. on Tsuga canadensis (L.) Carr. in eastern North America, and on Tsuga heterophylla (Raf.) Sarg. and Tsuga mertensiana (Bong.) Carr. in western North America; Epipolaeum pseudotsugae (V. M. Miller & Bonar) n. comb. on Pseudotsuga taxifolia (Poir.) Britton from western North America; Epipolaeum terrieri (Petrak in Terrier) n. comb. on Abies alba in Switzerland.
DIFFERENTIAL SENSITIVITY OF DIPHENYL-SENSITIVE AND DIPHENYL-TOLERANT STRAINS OF FUNGI TO CHLORINATED NITROBENZENES AND TO SOME DIPHENYL DERIVATIVES
Authors: Georgopoulos S. G. , Vomvoyanni Vassiliki E.
Published: August 2008

In Hypomyces solani f. cucurbitae the inhibitory effect of diphenyl on spore germination, germ tube development, and subsequent growth was overcome by mutation to chloronitrobenzene tolerance at any of three previously known loci. Sectoring under the selective action of diphenyl similarly resulted in tolerance to chloronitrobenzenes. One mutant gene is sufficient to give the maximum diphenyl tolerance possible. Results of cross-tolerance tests with differentially sensitive strains of three other fungi showed the same relationship between diphenyl tolerance and chloronitrobenzene tolerance. Neither volatilities nor relative saturations were found to be of importance in an understanding of the reason for this relationship. Diphenyl-tolerant strains are also tolerant to compounds derived from diphenyl by simple substitutions. The magnitude of the tolerance may be influenced by the substituent, the position, and the fungus species.
DORMANCY STUDIES IN SEED OF AVENA FATUA 4. : THE ROLE OF GIBBERELLIN IN EMBRYO DORMANCY
Authors: Simpson G. M.
Published: August 2008

Initiation of germination and subsequent growth of naked dormant embryos of Avena fatua L. require an exogenous source of sugar, amino acids, and gibberellic acid (GA). Non-dormant embryos can grow on sugar and amino acids, without exogenous GA, because they produce endogenously a gibberellin-like factor. This factor is absent in freshly matured dormant embryos but increases in amount with length of afterripening for several years, then decreases steadily. The action on embryos of exogenous GA and the endogenous GA-like factor is to promote the synthesis of enzymes or possibly to activate preformed enzymes necessary for the utilization of endosperm as the substrate for germination and growth. The levels of free phosphate and specific activity of 3′-nucleotidase, and ability to synthesize soluble protein between 24 and 48 hours, are markedly restricted in highly dormant embryos and GA can overcome these restrictions.
QUANTITATIVE AND QUALITATIVE COMPARISONS OF FUSARIUM POPULATIONS IN CULTIVATED FIELDS AND NONCULTIVATED PARENT SOILS
Authors: Nash Shirley M. , Snyder William C.
Published: August 2008

In soils of the Salinas watershed Fusarium solani and Fusarium tricinctum were found only in the cultivated soils. Propagules of Fusarium oxysporum were numerous and varied in the cultivated fields but were relatively scarce and existed essentially as a single clone in the noncultivated soils. In the Castroville watershed both F. solani and F. oxysporum were recovered from noncultivated soils fairly frequently.The 'Gibbosum' cultivar of Fusarhim roseum, the most frequently isolated fusarium from field soils, was less common in the noncultivated soils.Other fusaria, such as Fusarium episphaeria and some cultivars of F. roseum, were about as numerous in the noncultivated as in the cultivated soils. The cultivation of these soils markedly affected the makeup of the fusarium populations in them.
DISTRIBUTION AND PREVALENCE OF VERTICILLIUM SPECIES PRODUCING SUBSTANCES WITH GIBBERELLIN-LIKE BIOLOGICAL PROPERTIES
Authors: Aubé C. , Sackston W. E.
Published: August 2008

One hundred and fourteen isolates of Verticillium species were tested for production of gibberellin-like substances ("gibberellins") using dwarf mutant seedlings of Zea mays. Twenty-one isolates induced statistically significant growth increases attributed to "gibberellins". Activity was observed in isolates of V. albo-atrum, V. dahliae, V. nigrescens, and V. lateritium, from various hosts, and from various locations in Canada, United States, and Great Britain. "Gibberellin" was apparently produced also by isolates of Colletotrichum, Chaetomium, Penicillium, and Rhizoctonia solani. "Gibberellin" may be produced commonly by isolates of Verticillium, and possibly by other fungi as well.Some isolates of Verticillium apparently produced substances which inhibited growth of dwarf-mutant corn seedlings.
DEVELOPMENT OF THE SEED AND FRUIT IN MELAMPYRUM NEMOROSUM L. AND M. ARVENSE L.
Authors: Tiagi B.
Published: August 2008

The ovary is bilocular, with four massive axile placentae, each bearing a sessile hemianatropous, unitegmic, and tenuinucellate ovule. The innermost integumentary layer forms endothelium around the micropylar part of the embryo sac. The micropylar canal is surrounded by the micropylar tube, whereas the endothelium is hypodermal in this region. The endothelium and an adjacent meristematic region contribute to the growth of the integument. The endosperm is of the Brunella type described by K. Schnarf in 1929. The chalazal haustorium is a highly aggressive, two-nucleate chamber which becomes inactive and is filled with a haustorial chalazal endosperm. The two multinucleate micropylar haustorial cells give rise to many tubular extensions which pass through the micropylar tube, but only one reaches the placenta. The cells of the storage endosperm are pitted and thickened with hemicellulose. An opaque tanniferous zone of endosperm separates the storage endosperm from the chalazal endosperm. The embryo is small and straight, with two cotyledons and a hypocotyledonary region. The seed coat is feeble, one to three layered. The pericarp is many layered and cuticularized. The two innermost lignified layers form columns at the dorsal line of the two valves of the capsule, where it dehisces. The chalazal part of the developing seed absorbs nourishment directly from the pericarp.
WEED COMPLEXES ON ABANDONED PASTURES AS INDICATORS OF SITE CHARACTERISTICS
Authors: Dale Hugh M.
Published: August 2008

Prepared check lists of specific weeds on abandoned pastures were used to determine the frequency of concurrence of each pair of species. Contingency tables showing the degree of association of the species taken two at a time were used to work out constellation diagrams which showed several allied complexes. Each complex was found to be associated with certain physical site conditions.
ON THE OCCURRENCE OF ROOT BUDS ON PERENNIAL PLANTS IN SASKATCHEWAN
Authors: Raju M. V. S. , Coupland R. T. , Steeves T. A.
Published: August 2008

A survey of dicotyledonous species of the prairie and forest regions of southern Saskatchewan disclosed the occurrence of 38 species (12 introduced, 26 native) which produce adventitious buds on their roots.
SPOROTRICHUM THERMOPHILE IN NORTH AMERICA
Authors: Semeniuk G. , Carmichael J. W.
Published: August 2008

A cellulolytic, thermophilic Hyphomycete isolated from molding, open-stack alfalfa silage and from fir and spruce pulpwood chips was identified as Sporotrichum thermophile Apinis, recently described from soil and plant material in Britain. A fuller description of S. thermophile is given and its generic placement discussed.
CELL LENGTH AND RATE OF ANTICLINAL DIVISION IN THE CAMBIUM OF THE SEQUOIAS
Authors: Bannan M. W.
Published: August 2008

This report deals with the frequency of anticlinal (multiplicative) divisions in fusiform cambial cells, cell length at the time of division, and ring width as determined mostly in Sequoia sempervirens. The general relationships between these anatomical features resembled those observed in other conifers, but the frequency of anticlinal division was relatively high and the cells were long. Accordingly, the rate of cambial cell lengthening in the repetitive cycle of anticlinal division and cell elongation was found to exceed that in other conifers. Upward in the lower part of the stem the rate of anticlinal division decreased and cell length increased. A comparatively high rate of anticlinal division was maintained in the peripheral growth of large boles in both species, but cell length was greater in S. sempervirens than in S. gigantea.
FUCKEL'S MASSARIA MARGINATA AND SEIRIDIUM MARGINATUM NEES EX STEUDEL
Authors: Shoemaker R. A. , Müller Emil , Morgan-Jones G.
Published: August 2008

Blogiascospora n. gen. is described for B. marginata (Fuckel) n. comb. (≡ Massaria marginata Fuckel) because study of the type revealed that the asci are unitunicate with a pulvillus and amyloid annulus, and that the ascospore walls are pitted. Study of Fuckel's specimens tended to confirm his conclusion that Seiridium marginatum Nees ex Steudel is the conidial state. Von Höhnel's confirmation of this connection was not borne out by a re-examination of his specimens. S. marginatum is redescribed and illustrated from a neotype. These characters are emphasized: the hydrophilic outer layer of the conidiophore, the echinulations arranged in longitudinal ridges on the four central cells of the conidia, and the sequence of septum formation beginning near both ends of the conidia. The taxonomy and nomenclature of S. marginatum and Seiridium Nees ex Fr. are discussed.
CULTURAL CHARACTERISTICS OF THREE SPECIES OF BOLETINUS
Authors: Laut John G.
Published: August 2008

Three main categories of culture characteristics were examined: gross morphology of the growing colony, microscopic morphology of the mycelium, and chemistry of the mycelium as expressed by color changes induced by specific chemical reagents. The diagnostic characteristics for the three species studied have been arranged into a numerical key that is amenable to expansion as data for more species become available.
THE OCCURRENCE OF ENDOPHYTIC FUNGI IN DOUGLAS-FIR SEEDLINGS AND SEED
Authors: Bloomberg W. J.
Published: August 2008

Segments taken from the roots and shoots of healthy 1-year-old seedlings of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) collected over a 2-year period from two British Columbia forest nurseries, were surface-sterilized, and incubated on various media. Fungi grew from segments of over 80% of the seedlings, the most frequent being Fusarium oxysporum Schlecht., F. redolens Wr., Mycelium radicis atrovirens, Cylindrocarpon didymum (Hart.) Wollenw., and C. radicicola Wollenw. Fungi were isolated more frequently from the shoot than from the root segments. Isolations from segments with the bark intact were more frequent than from segments that had the bark removed. Seedlings collected in the winter produced more fungi than those collected during the summer. Segments from diseased seedlings and seedlings grown under sterile conditions produced mycofloras which were different from each other and from that of healthy nursery-grown seedlings. Without exception, fungi grew from surface-sterilized seed placed on malt agar and samples from different seedlots had different floras. Stained sections clearly showed hyphae and chlamydospores well within the tissue of roots, shoots, and seed coat.
CHROMOSOME NUMBERS FROM CENTRAL NORTHERN CANADA
Authors: Löve Áskell , Ritchie J. C.
Published: August 2008

Chromosome numbers are reported for 93 taxa from central northern Canada. It is pointed out that the collective species Dupontia fisheri actually includes three species differing in chromosome number, viz., D. psilosantha (2n = 44), D. pelligera (2n = 88), and D. fisheri s. str. (2n = 132). The taxon often named Carex saxatilis var. major is identified with C. physocarpa with 2n = 60 chromosomes whereas C. saxatilis s. str. has 2n = 80. Two new combinations are proposed: Argentina anserina ss. EGEDII (Wormskj.) Löve & Ritchie, and Menyanthes trifoliata ssp. MINOR (Raf.) Löve & Ritchie.
TAXONOMY OF NORTH AMERICAN PLANTAGO L., SECTION MICROPSYLLIUM DECNE.
Authors: Bassett I. J.
Published: August 2008

Evidence is presented that the western Plantago elongata Pursh and P. bigelovii Gray are distinct taxa, each with two populations recognized by the author as subspecies. Plantago elongata ssp. elongata, 2n = 12, is found from Manitoba to British Columbia and southward to Texas and California and ssp. pentasperma Bassett, 2n = 12 and 36, occurs west of the Coast, Cascade Mountains, and Sierra Nevada from British Columbia to California. Plantago bigelovii ssp. bigelovii, 2n = 20, is mainly a plant of the western coastline from British Columbia to California while ssp. californica (Greene) Bassett comb, nov., 2n = 20, is native only to California, Arizona, and Mexico. Plantago heterophylla Nutt., 2n = 12, is widely scattered in the south eastern portion of the United States from Texas to the eastern coastline, while Plantago pusilla Nutt., 2n = 12, occurs mainly in the central eastern states.
TWO TYPES OF ALBUGO-INDUCED GALLS ON IPOMOEA PENTAPHYLLA AND THEIR MORPHOGENETIC INTERPRETATION
Authors: Singh Hardev , Bedi Krishna
Published: August 2008

Ipomoea pentaphylla Jacq. is a twining, hirsute annual. After infection by Albugo ipomoeae-panduranae (Schw.) Swingle, two types of galls develop on the stem—bud and cerebriform. The bud gall originates from an infected bud while the cerebriform gall arises from the internode. The two types are distinct from each other in their morphology, anatomy, rate of development, and morphogenesis. The bud gall is of the organoid type while the cerebriform gall is of the histioid type. Tissues of the bud gall grown under in vitro conditions give rise to a structure like the cerebriform gall. The very distinct morphology of the two types has been interpreted on the basis of the possible organizing influence of the shoot apical meristem.
NOTES ON THE NOMENCLATURE OF NOTHOPHACIDIUM PHYLLOPHILUM COMB. NOV., ITS PATHOGENICITY AND RELATIONSHIP TO PEZIZELLA MINUTA
Authors: Smerlis E.
Published: August 2008

A new combination, Nothophacidium phyllophilum, is proposed for Nothophacidium abietinellum (Dearn.) Reid & Cain. This fungus is a secondary invader of needles of balsam fir (Abies balsamea (L.) Mill.) infected by Hypodermella spp. Pezisella minuta Dearn., occurring on needles of hard pines, is similar to, if not identical with, N. phyllophilum.
FUNGI FROM DWARF MISTLETOE INFECTIONS IN WESTERN HEMLOCK
Authors: Baranyay J. A.
Published: August 2008

Nine ascomycetes and two fungi imperfecti were found associated with cankers on branch swellings caused by western hemlock dwarf mistletoe, Arceuthobium campylopodum Engelm. forma tsugensis Gill, in an investigation in the coastal forest of British Columbia. One ascomycete is described as Durandiella tsugae sp. nov. The following fungi are discussed: Lachnellula agassizii (Berk, and Curt.) Dennis, Caliciopsis pseudotsugae Fitzp., Capnodium spongiosum Barr, Durandiella tsugae Baranyay sp. nov., Helotium sp., Lophium mytilinum (Pers.) Fries, Mytilidion tortile (Schw.) Ell. & Ev. non Sacc, Retinocyclus abietis (Crouan) Groves & Wells, Biatorella resinae (Fr.) Mudd., Epicoccum nigrum Link, and Truncatella truncata (Lév.) Steyaert.
CRUMIA, A NEW GENUS OF THE POTTIACEAE ENDEMIC TO WESTERN NORTH AMERICA
Authors: Schofield W. B.
Published: August 2008

A new genus of the Pottiaceae, Crumia, is proposed to accommodate Merceya latifolia Kindb. This species is shown not to be closely related to Merceya, but probably has greater affinity to Tortula and Desmatodon. Both sporophyte and gametophyte are described and illustrations show detailed structure and distribution.
FLORAL INITIATION IN STRAWBERRY AND SOME EFFECTS OF RED AND FAR-RED RADIATION AS COMPONENTS OF CONTINUOUS WHITE LIGHT
Authors: Collins W. B.
Published: August 2008

The effects of different ratios of red to far-red radiation in continuous light on flower initiation in strawberry are described. A correlation was found between flower promotion and the content of far-red light in the supplied radiation which may be related to the red/far-red ratio of light and therefore to the level of phytochrome-Pfr in the plants. However, since relatively high energy (white) light was the only radiation used, a clear distinction between photosynthetic and red/far-red photoreversible effects is not possible. Flowering did not occur on all runner plants. Where flowering was promoted it invariably occurred first on the second- or third-formed runner plants on the stolon. Flowering was delayed on the proximal runner plants and never occurred on the mother plants. The results support the premise that a flower-inhibiting system was present along a concentration gradient in the runner.
GIBBERELLIN, AS A REGULATOR OF PROTEIN AND RIBONUCLEIC ACID SYNTHESIS DURING SENESCENCE IN LEAF CELLS OF TARAXACUM OFFICINALE
Authors: Fletcher R. A. , Osborne Daphne J.
Published: August 2008

The addition of gibberellin A3 (GA) to leaf discs of Taraxacum officinale Weber retards their senescence and delays the decline in the levels of chlorophyll, protein, and RNA. Incorporation of 14C leucine and 14C adenine into protein and RNA respectively was increased by GA. This enhancement of protein and RNA synthesis did not occur if the discs were supplied with actinomycin D before treatment with gibberellin. If, however, actinomycin D was added after the gibberellin treatment then the stimulatory effect of the hormone was maintained. These results suggest that the retarding action of gibberellins on leaf senescence could be mediated through a regulation of RNA synthesis that is DNA dependent.
BLOSSOMING AND FRUIT SET PATTERNS IN PHASEOLUS VULGARIS L. AS INFLUENCED BY TEMPERATURE
Authors: Stobbe Elmer H. , Ormrod Douglas P. , Woolley C. Joy
Published: August 2008

Plants of Phaseolus vulgaris were grown under controlled conditions at day/night temperatures of 24.0/15.5, 29.5/21.0, and 35.0/26.5 °C for measurement of blossoming and fruit set patterns over a 60-day period of blossoming. Fruit removal at a large green stage was compared with fruit removal at dry maturity and with removal of all blossoms. Removal of fruit at a large green stage resulted in cyclic patterns of blossoming at the two lower temperatures with a greater proportion of blossoms setting fruit in later cycles. When all blossoms were removed, the cyclic pattern was not as pronounced. When fruit were removed at dry maturity only one blossoming cycle occurred and the plants senesced. The numbers of blossoms and fruit were greatest at 29.5/21.0 °C.
DEVELOPMENT OF FRUCTIFICATIONS IN COLLETOTRICHUM GRAMINICOLA (CES.) WILS. AND RELATED SPECIES
Authors: Sutton B. C.
Published: August 2008

The development of fructifications in Colletotrichum graminicola (Ces.) Wils. is compared with that of other Colletotrichum species occurring naturally on graminicolous and non-graminicolous hosts. Two types are distinguished: (a) the pulvinate in which the outer epidermal wall and cuticle are ruptured at the same time by the developing conidiophores, setae, and stromatic tissue, and (b) the hypostromatic in which the outer epidermal wall is penetrated by fine hyphae from the epidermal stroma, the cuticle being ruptured separately by the setae and conidiophores. Colletotrichum graminicola on a wide range of graminicolous hosts exhibits only the pulvinate type, but other Colletotrichum species develop in either way depending on the nature of the substrate and the strain of fungus involved. The generic separation of C. graminicola from other species by this criterion is not accepted.
NUTRIENT SUPPLEMENTATION OF MUSHROOM COMPOST AT CASING: VEGETABLE OILS
Authors: Schisler L. C. , Sinden J. W.
Published: August 2008

Supplementation of compost at casing with various ground seeds caused greater increases in mushroom yield than their respective seed oil meals when supplemented and compared at equivalent rates of nitrogen addition.Supplementation with various refined and crude seed oils increased mushroom yield, particularly in the first break or flush of mushrooms. This constitutes evidence for a relationship between lipid metabolism and the initiation of fruiting in the cultivated mushroom, Agaricus bisporus (Lange) Sing.
THE TEMPERATURES OF SURFACE FIRES IN JACK PINE BARREN: II. THE EFFECTS OF VEGETATION COVER, WIND SPEED, AND RELATIVE HUMIDITY ON FIRE TEMPERATURES
Authors: Sparling John H. , Smith David W.
Published: August 2008

The maximum temperature attained during surface fires in a jack pine barren, near Timmins, Ontario, was found to vary from 120° to 545 °C. The temperature of the fire is dependent upon a number of variables, of which vegetation biomass and height, wind speed, the speed of the fire front, and moisture content of litter and vegetation, are most important.Temperatures of fires studied depended mainly on the height and amount of burning vegetation. All fires with temperatures greater than 350 °C occurred in dense vegetation with more than 235 g/m2. The effects of wind velocity were less obvious; however, high wind speed appeared to have a cooling effect on the fire temperature.There was no evidence of any significant effect of atmospheric humidity on fire temperature.
CULTURAL STUDIES OF BOLETACEAE: SOME SPECIES OF SUILLUS AND FUSCOBOLETINUS
Authors: Pantidou Maria E. , Groves J. Walton
Published: August 2008

Eighteen species of Suillus and three species of Fuscoboletinus were studied in culture. Both macroscopic and microscopic cultural characters are described and a key to the species studied is presented.
BEHAVIOR OF PRIMARY AND SECONDARY ZOOSPORES OF SAPROLEGNIA SP.
Authors: Crump Eleanor , Branton Daniel
Published: August 2008

The behavior of primary and secondary zoospores of Saprolegnia sp. was studied by phase microscopy. In particular the fate of their flagella upon encystment was examined. It was shown that primary zoospores withdraw their flagella, whereas secondary zoospores shed their flagella upon encystment.
GROWTH AND DEVELOPMENT OF MYCORRHIZAE OF SUGAR MAPLE (ACER SACCHARUM MARSH.)
Authors: Kessler Kenneth J.
Published: August 2008

Beaded rootlet growth in Acer saccharum is thought to be caused by intermittent growth due to alternately favorable and unfavorable moisture conditions during the season rather than by mycorrhizal infection. Both beaded and nonbeaded rootlets are mycorrhizal-infected, and rootlets growing in the deeper soil levels where moisture conditions do not fluctuate rapidly are nonbeaded. Differences found in the activity of rootlets growing in hummocks and depressions appeared to be related to soil moisture conditions found there. This paper describes (a) the anatomy of metacutinized root tips during dry soil conditions, and the relationship of this condition to the development of constrictions between beads; (b) the extrastelar anatomical characteristics of beaded and nonbeaded rootlets; (c) the morphology of the mycorrhizal fungus in its relationship to rootlet anatomy; (d) the extramatrical mycelium of the mycorrhizal fungus found in the soil of the rooting zone (the extramatrical mycelium is thought to arise from fungal hyphae and vesicles produced in live rootlets which are released to the soil from disintegrating rootlet cortical tissue); and (e) an hypothesis regarding the life history of this type of vesicular–arbuscular mycorrhizal fungus.
ROLE OF NITROGEN IN WOOD DETERIORATION: AMOUNTS AND DISTRIBUTION OF NITROGEN IN TREE STEMS
Authors: Merrill William , Cowling Ellis B.
Published: August 2008

Radial gradients in nitrogen content across stems of three hardwoods and two softwoods followed similar patterns. Sapwood and inner bark contained a higher proportion of the total nitrogen in cross sections than heartwood and outer bark, respectively. Nitrogen content of individual annual increments decreased progressively from the cambium to the transition zone between sapwood and heartwood, or, in species without heartwood, to the increments nearest the pith. In some cases, an abrupt decrease in nitrogen content was observed across the sapwood–heartwood boundary. The diminution of nitrogen content across the sapwood was associated with death of parenchyma cells. As the cells die, nitrogen in their cytoplasm apparently is retrieved for possible reuse elsewhere in the tree. Pith contained more nitrogen by weight than heartwood and in some cases more than sapwood. Nitrogen content was correlated directly with parenchyma volume for sapwood but not for heartwood of 16 species of angiosperms.Nitrogen extractable from sapwood with neutral solvents consisted in part of free amino acids but only traces of these acids were detected in heartwood. Hydrolysates of sapwood and heartwood prepared with 6 N HCl contained many typical protein amino acids.
THE OCCURRENCE OF PHYTOPHTHORA SPP. IN IRRIGATION SYSTEMS IN BRITISH COLUMBIA
Authors: McIntosh D. L.
Published: August 2008

Twenty-seven of 31 irrigation sources serving the Okanagan and Similkameen valleys of British Columbia were contaminated with Phytophthora. P. cactorum, the cause of collar rot of fruit trees in this region, was recovered from 15 sources; P. cambivora and P. citricola from 1 each; P.. megasperma from 4 sources. Many isolates of uncertain identity also were recovered. P. cactorum, P. cambivora, and P. citricola were pathogenic to rootlets of young apple seedlings in laboratory tests, but only P. cactorum is considered an important pathogen in this region.
DIFFERENCES IN DROUGHT RESISTANCE BETWEEN COASTAL AND INLAND SOURCES OF DOUGLAS FIR
Authors: Pharis Richard P. , Ferrell William K.
Published: August 2008

By two drought-hardiness tests, "time to death" and "soil-moisture content at the death point", Douglas-fir seedlings from three coastal sources were shown to be less drought resistant than those from five inland sources. Lethal needle-moisture contents, although not a proved test of drought hardiness, tend to confirm this conclusion. In addition, these lethal needle-moisture values, useful as an index of whole plant viability, were established for the various sources. Two of the coastal sources differed from five inland sources in the level of this value, but the lethal points for two other sources from the Oregon Cascade Range were similar to the five inland sources. Needle moisture appears to be a workable index for determining the whole plant viability except when the plant is very close to its time of death. Plants could also be classified into coastal and inland groups on the basis of their needle moisture under well-watered conditions, with the exception of seedlings from the Arizona source which are like the coastal group.
THE SEPARATION OF THE PROTEINS OF WHEAT BY ACRYLAMIDE GEL ELECTROPHORESIS, WITH SPECIAL REFERENCE TO MOTTLED AND UNMOTTLED WHEAT
Authors: Barber J. T. , Wood H. L. , Steward F. C.
Published: August 2008

The proteins of wheat grains were studied by the technique of acrylamide gel electrophoresis. This study provided the opportunity to show the effects, on the proteins resolved by these methods, of different factors and variables. These include some items of technique, effects due to the variety to which the grains belong and to the condition known as mottling, and some correlations with the morphology of the grain and with changes that accompany germination. Albumins and globulins were extracted from whole ungerminated mottled and unmottled wheat grains (var. Festival), from embryos of mottled and unmottled grain, and from the various parts of grain germinated for 2, 4, and 6 days under defined conditions. The extracted proteins were separated on [Formula: see text] acrylamide gels at pH 8.3. Glutens were extracted from the same materials and were separated on [Formula: see text] acrylamide gels at pH 5.0; some were separated at pH 4.5 also. The albumins and globulins and glutens of the whole ungerminated grain of three varieties of mottled and unmottled wheat are described and differences due to variety and mottling are discussed. The protein patterns of whole grain, dominated by endosperm, were remarkably constant though varietal effects were seen. Albumin and globulin and gluten fractions each had characteristic patterns but the observed differences between mottled and unmottled grain were quantitative, not qualitative. Proteins of embryos differed from those of endosperm and upon germination complementary changes in endosperm and embryo (roots and shoots) proteins could be observed.
THE PRAIRIE, MEADOW, AND MARSH VEGETATION OF NELSON COUNTY, NORTH DAKOTA
Authors: Dix R. L. , Smeins F. E.
Published: August 2008

The objectives of the study were to determine the general phytosociological structure of the native prairies, meadows, and marshes of Nelson County, North Dakota; to establish relationships between this structure and factors of the physical environment; and to evaluate the relationships between the vegetation of Nelson County and the True and Mixed prairies. Frequency values and environmental measurements on soil texture, salinity, pH, and an estimate of the drainage regime were obtained in 100 stands selected to represent the vegetational diversity within the County. The drainage regime proved to be the most important single environmental factor in determining the vegetation. A phytosociological drainage regime gradient was then established by assigning indicator values to selected species, and the behaviors of all species and environmental factors were displayed along this gradient. The vegetational display was then divided into six units: the uplands into high prairie, mid prairie, and low prairie and the lowlands into meadow, marsh, and cultivated depressions. Each vegetational unit is described. Comparisons are made between each unit and the related vegetation in surrounding areas. It is concluded that Nelson County should be considered to be within the geographical area of the True Prairie, although the frequent occurrence of western grassland types and western species suggests that the County is within the tension zone between the True and Mixed prairies.
MEIOSIS IN COPRINUS ATRAMENTARIUS
Authors: McClaren Milton
Published: August 2008

Meiosis in Coprinus atramentarius Fries was studied by the use of an acetocarmine squash technique. Discrete chromosomes were noted only during meta-phase–anaphase of the first meiotic division. The diploid chromosome number was determined as six. During the second meiotic division chromatin masses, rather than discrete chromosomes, were seen to separate. In both meiosis I and II, centrosomes were formed at the poles of the division figures.
MORPHOLOGICAL AND ANATOMICAL STUDIES ON LEPISORUS SUBROSTRATUS (HOOK.) C. CHR., L. MACROSPHAERUS (BAK.) CHING, AND L. KASHYAPII (MEHRA) MEHRA
Authors: Srivastava Prem
Published: August 2008

Three species of Lepisorus, namely L. subrostratus (Hook.) C. Chr., L. macrosphaerus (Bak.) Ching, and L. kashyapii (Mehra) Mehra have been studied in detail. The plants are semiepiphytes or epiphytes having branched, creeping rhizomes attached to the substratum by clusters of thin, dark brown roots. The fronds are simple lanceolate to linear and arranged in two alternating rows, having long or short petioles. The three species possess a dictyostelic rhizome. The petiole has many vascular bundles and the lamina a T-shaped xylem. Large, rounded sori are present in a single row on either side of the midrib. Sporangia are leptosporangiate and protected by clathrate peltate paraphyses in all the species studied. The spores are monolete and bilateral and have a two-layered verrucate to granulate exine.
THE DEVELOPMENT OF ECHINULATION IN UREDOSPORES OF WHEAT STEM RUST
Authors: Thomas P. L. , Isaac P. K.
Published: August 2008

Electron microscopy was used to determine the sequence of events in the formation of spines on the uredospore walls of P. graminis tritici. The micrographs show that spines develop to mature size beneath the uredospore wall and then move or pass through the wall to its surface during the expansion and maturation of the spore.