bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Growth Mechanism of Lead Titanate Nanotube Arrays by Hydrothermal Method
Authors: Yang Yang , Wang Xiaohui , Zhong Caifu , Sun Changku , Yao Guofeng , Li Longtu
Published: August 2008

Lead titanate nanotube arrays were in‐situ grown by hydrothermal synthesis. The hydrothermal process is time‐dependent and in different hydrothermal reaction stages, different growth mechanisms dominate the formation of PbTiO3 nanotubes. In the initial stage in‐situ growth of PbTiO3 nanotube arrays dominates. Subsequently dissolution–precipitation process dominates and results in the deposition of PbTiO3 particles on the surface of the already‐formed PbTiO3 nanotubes. In order to in‐situ grow PbTiO3 nanotube arrays with perfect nanotubular structure, suitable hydrothermal reaction time should be applied.
Evaluation of Shooting Distance by AFM and FTIR/ATR Analysis of GSR
Authors: Mou Yongyan , Lakadwar Jyoti , Rabalais J. Wayne
Published: August 2008

Abstract:  The techniques of atomic force microscopy (AFM) and Fourier transform infrared attenuated total reflectance (FTIR/ATR) spectroscopy are applied to the analysis of gun‐shot residue (GSR) to test their ability to determine shooting distance and discrimination of the powder manufacturers. AFM is a nondestructive technique that is capable of characterizing the shapes and size distributions of GSR particles with resolution down to less than a nanometer. This may be useful for estimation of the shooting distance. Our AFM images of GSR show that the size distribution of the particles is inversely proportional to the shooting distance. Discrimination of powder manufacturers is tested by FTIR/ATR investigation of GSR. Identifying the specific compounds in the GSR by FTIR/ATR was not possible because it is a mixture of the debris of several compounds that compose the residue. However, it is shown that the GSR from different cartridges has characteristic FTIR/ATR bands that may be useful in differentiating the powder manufacturers. It appears promising that the development of AFM and FTIR/ATR databases for various powder manufacturers may be useful in analysis and identification of GSR.
What works for whom in a computer‐mediated communication intervention in community psychiatry? Moderators of outcome in a cluster randomized trial
Authors: Hansson L. , Svensson B. , Björkman T. , Bullenkamp J. , Lauber C. , Martinez‐Leal R. , McCabe R. , Rössler W. , Salize H. , Torres‐Gonzales F. , Van Den Brink R. , Wiersma D. , Priebe S.
Published: August 2008

Objective:  An intervention to structure patient–key worker communication has been tested in a randomized controlled trial. The aim of this paper was to investigate effectiveness of the intervention in terms of moderators of effectiveness.

Method:  A total of 507 patients with schizophrenia were included. Moderators of effectiveness were investigated using two‐way anovas.

Results:  Patients with a better relationship with their key worker and a shorter duration of illness at baseline benefited more from the intervention in terms of quality of life. Patients who received the intervention who were in competitive employment or had a shorter duration of illness showed greater reduction of unmet needs. Older patients receiving the intervention had better treatment satisfaction.

Conclusion:  Outcome of the intervention was moderated by patient characteristics. Moreover, the moderating characteristics varied depending on the specific outcome. Evidence on moderators is very limited, even though, they are significant for understanding, targeting and implementing complex interventions.
MAGNETIC RESONANCE IMAGING FINDINGS IN HISTOLOGICALLY CONFIRMED PUG DOG ENCEPHALITIS
Authors: FLEGEL THOMAS , HENKE DIANA , BOETTCHER IRENE C. , AUPPERLE HEIKE , OECHTERING GERHARD , MATIASEK KASPAR
Published: August 2008

The purpose of the study was to describe magnetic resonance (MR) imaging features of histologically confirmed necrotizing encephalitis in four Pugs and to compare those findings with MR imaging characteristics of necrotizing encephalitis in other breeds. All dogs had the following common findings: lesions restricted to the forebrain, both cerebral hemispheres diffusely but asymmetrically affected, lesions affected gray and white matter resulting in loss of distinction between both, most severe lesions in occipital and parietal lobes, lesions were irregularly T2‐hyperintense and T1‐isointense to slightly T1‐hypointense, and no cavitation. There were various degrees of contrast enhancement of brain and leptomeninges. Asymmetry of lateral ventricles and midline shift was seen in one dog each. Two dogs had brain herniation, which may have contributed to the progression of neurologic signs. Hyperintensity on T2‐weighted and fluid attenuated inversion recovery images in the hippocampus and piriform lobe was consistent with excitotoxic edema, whereas similar imaging features in other forebrain areas corresponded to areas of inflammation or liquefaction on histopathology. In comparison with necrotizing encephalitis in other canine breeds, Pug dog encephalitis has some unique MR imaging features. Therefore, these characteristics cannot be applied to other breeds, nor should imaging features of necrotizing encephalitis of other canine breeds be used for interpretation of MR images in Pug dogs.
Minard and Napoleon's March on Moscow
Authors: Joyce Helen
Published: August 2008

Some graphics portray more than mere data. Helen Joyce describes a diagram of genius that brings home the horror of Napoleon's most terrible campaign.
Outcomes Important to People With Intellectual Disabilities
Authors: Miller Emma , Cooper Sally‐Ann , Cook Ailsa , Petch Alison
Published: August 2008

Abstract  An emphasis on the outcomes of health and social care services has become increasingly apparent within public policy in the United Kingdom. Alongside this, working in partnership has been a key theme, despite a relatively underdeveloped evidence base. Of central importance, however, must be whether directives toward partnership working are delivering improved outcomes, and in particular, the outcomes that are valued by service users. The authors describe a project that sought to identify the outcomes important to people with intellectual disabilities, and where possible, whether partnerships delivered these outcomes. The research was primarily based on interviews with service users and carers, and involved people with intellectual disabilities as both researchers and research subjects. The project categorized key outcomes in two categories (quality of life and process) and identified ways in which health and social care partnerships can deliver the outcomes service users want. If agencies are to deliver good outcomes to users, as increasingly emphasized in policy, this focus should accurately reflect the outcomes that users themselves define as important.
The adoption of IFRS in Australia: The case of AASB 138 (IAS 38) Intangible Assets
Authors: Cheung Esther , Evans Elaine , Wright Sue
Published: August 2008

AASB 138 Intangible Assets, adopted by reporting entities in Australia for annual reporting periods beginning on or after 1 January 2005, required derecognition of internally generated intangible assets. Prior to its adoption, the standard was widely expected to have a substantial impact on the reports of affected listed entities. On the basis of information available in the 2004/05 annual reports, this paper projects the expected effects of AASB 138 on reported intangible assets and on key financial measures. It compares these projected measures to the realised measures, reported under both Australian GAAP and AIFRS in the 2005/06 reports. While reported intangible assets and the debt to equity ratio were expected to change significantly as a result of AASB 138, the reported AIFRS results show a significant change in only the debt to equity ratio. The paper considers reasons why the pre‐adoption expected changes did not eventuate, and also how the actual changes were reported to stakeholders in the management discussion sections of the annual reports. The conclusion draws implications regarding the transparency of communication in annual reports.
Primary CD8+T-Cell Response to Soluble Ovalbumin Is Improved by Chloroquine Treatment In Vivo
Authors: Garulli Bruno , Stillitano Maria G. , Barnaba Vincenzo , Castrucci Maria R.
Published: August 2008

The efficiency of cross-presentation of exogenous antigens by dendritic cells (DCs) would seem to be related to the level of antigen escape from massive degradation mediated by lysosomal proteases in an acidic environment. Here, we demonstrate that a short course of treatment with chloroquine in mice during primary immunization with soluble antigens improved the cross-priming of naïve CD8+T lymphocytes in vivo. More specifically, priming of chloroquine-treated mice with soluble ovalbumin (OVA), OVA associated with alum, or OVA pulsed on DCs was more effective in inducing OVA-specific CD8+T lymphocytes than was priming of untreated mice. We conclude that chloroquine treatment improves the cross-presentation capacity of DCs and thus the size of effector and memory CD8+T cells during vaccination.
Rapid and Inexpensive Detection of Multidrug-Resistant
Mycobacterium tuberculosis
with the Nitrate Reductase Assay Using Liquid Medium and Direct Application to Sputum Samples
Authors: Affolabi Dissou , Odoun Mathieu , Sanoussi N'Dira , Martin Anandi , Palomino Juan Carlos , Kestens Luc , Anagonou Séverin , Portaels Françoise
Published: August 2008

For rapid and low-cost detection of multidrug-resistant (MDR)
Mycobacterium tuberculosis
, we applied the nitrate reductase assay (NRA) using a liquid medium directly to sputum samples. A total of 179 sputum samples were analyzed by the NRA, and results were compared to those obtained by the indirect proportion method (IPM) as a standard reference. Out of 144 specimens for which comparable results were available, only one discrepant result was obtained: MDR by NRA but susceptible by the IPM. In total 56% of the results were obtained in 10 days by the NRA. NRA performed in liquid medium is rapid and inexpensive and can be easily implemented in low-income countries.
Capnocytophaga cynodegmi
in a Rottweiler Dog with Severe Bronchitis and Foreign-Body Pneumonia
Authors: Workman Heather C. , Bailiff Nathan L. , Jang Spencer S. , Zinkl Joe G.
Published: August 2008

Capnocytophaga cynodegmi
is a zoonotic, gram-negative, capnophilic bacterium that is usually seen in people with infections associated with dog or cat bites. The first reported case of
C
.
cynodegmi
infection in a dog is described here.
Proportions of
Mycobacterium massiliense
and
Mycobacterium bolletii
Strains among Korean
Mycobacterium chelonae-Mycobacterium abscessus
Group Isolates
Authors: Kim Hee-Youn , Kook Yoonwon , Yun Yeo-Jun , Park Chan Geun , Lee Nam Yong , Shim Tae Sun , Kim Bum-Joon , Kook Yoon-Hoh
Published: August 2008

Korean isolates of the
Mycobacterium chelonae
-
Mycobacterium abscessus
group, which had been isolated from two different hospitals in South Korea, were identified by PCR restriction analysis (PRA) and comparative sequence analysis of 16S rRNA genes,
rpoB
, and
hsp65
to evaluate the proportion of four closely related species (
M. chelonae
,
M. abscessus
,
M. massiliense
, and
M. bolletii
). Of the 144 rapidly growing mycobacterial strains tested, 127 strains (88.2%) belonged to the
M. chelonae
-
M. abscessus
group. In this group,
M. chelonae
,
M. abscessus
,
M. massiliense
, and
M. bolletii
accounted for 0.8% (
n
= 1), 51.2% (
n
= 65), 46.5% (
n
= 59), and 1.6% (
n
= 2), respectively. Two isolates which showed discordant results,
M. massiliense
by
rpoB
sequence analysis and
M. abscessus
by
hsp65
sequence analysis, were finally identified as
M. massiliense
based on the additional analysis of
sodA
and the 16S-23S internal transcribed spacer.
M. abscessus
group I isolates previously identified by
hsp65
PRA were all found to be
M. abscessus
, whereas group II isolates were further identified as
M. massiliense
or
M. bolletii
by sequencing of
rpoB
and
hsp65
. Smooth, rough, or mixed colonies of both
M. abscessus
and
M. massiliense
isolates were observed.
M. massiliense
strains that were highly resistant to clarithromycin had a point mutation at the adenine at position 2058 (A
2058
) or 2059 (A
2059
) in the peptidyltransferase region of the 23S rRNA gene.
Analysis of the 16S–23S rRNA Gene Internal Transcribed Spacer Region in
Klebsiella
Species
Authors: Wang Min , Cao Boyang , Yu Qunfang , Liu Lei , Gao Qili , Wang Lei , Feng Lu
Published: August 2008

The 16S-23S rRNA gene internal transcribed spacer (ITS) regions of
Klebsiella
spp., including
Klebsiella pneumoniae
subsp.
pneumoniae, Klebsiella pneumoniae
subsp.
ozaenae, Klebsiella pneumoniae
subsp.
rhinoscleromatis, Klebsiella oxytoca, Klebsiella planticola, Klebsiella terrigena
, and
Klebsiella ornithinolytica
, were characterized, and the feasibility of using ITS sequences to discriminate
Klebsiella
species and subspecies was explored. A total of 336 ITS sequences from 21 representative strains and 11 clinical isolates of
Klebsiella
were sequenced and analyzed. Three distinct ITS types—ITS
none
(without tRNA genes), ITS
glu
[with a tRNA
Glu (UUC)
gene], and ITS
ile+ala
[with tRNA
Ile (GAU)
and tRNA
Ala (UGC)
genes]—were detected in all species except for
K. pneumoniae
subsp.
rhinoscleromatis
, which has only ITS
glu
and ITS
ile+ala
. The presence of ITS
none
in
Enterobacteriaceae
had never been reported before. Both the length and the sequence of each ITS type are highly conserved within the species, with identity levels from 0.961 to 1.000 for ITS
none
, from 0.967 to 1.000 for ITS
glu
, and from 0.968 to 1.000 for ITS
ile+ala
. Interspecies sequence identities range from 0.775 to 0.989 for ITS
none
, from 0.798 to 0.997 for ITS
glu
, and from 0.712 to 0.985 for ITS
ile+ala
. Regions with significant interspecies variations but low intraspecies polymorphisms were identified; these may be targeted in the design of probes for the identification of
Klebsiella
to the species level. Phylogenetic analysis based on ITS regions reveals the relationships among
Klebsiella
species similarly to that based on 16S rRNA genes.
Foot-and-Mouth Disease Virus, but Not Bovine Enterovirus, Targets the Host Cell Cytoskeleton via the Nonstructural Protein 3C
pro
Authors: Armer Hannah , Moffat Katy , Wileman Thomas , Belsham Graham J. , Jackson Terry , Duprex W. Paul , Ryan Martin , Monaghan Paul
Published: August 2008

Foot-and-mouth disease virus (FMDV), a member of the
Picornaviridae
, is a pathogen of cloven-hoofed animals and causes a disease of major economic importance. Picornavirus-infected cells show changes in cell morphology and rearrangement of cytoplasmic membranes, which are a consequence of virus replication. We show here, by confocal immunofluorescence and electron microscopy, that the changes in morphology of FMDV-infected cells involve changes in the distribution of microtubule and intermediate filament components during infection. Despite the continued presence of centrosomes in infected cells, there is a loss of tethering of microtubules to the microtubule organizing center (MTOC) region. Loss of labeling for γ-tubulin, but not pericentrin, from the MTOC suggests a targeting of γ-tubulin (or associated proteins) rather than a total breakdown in MTOC structure. The identity of the FMDV protein(s) responsible was determined by the expression of individual viral nonstructural proteins and their precursors in uninfected cells. We report that the only viral nonstructural protein able to reproduce the loss of γ-tubulin from the MTOC and the loss of integrity of the microtubule system is FMDV 3C
pro
. In contrast, infection of cells with another picornavirus, bovine enterovirus, did not affect γ-tubulin distribution, and the microtubule network remained relatively unaffected.
Bluetongue Virus Outer Capsid Protein VP5 Interacts with Membrane Lipid Rafts via a SNARE Domain
Authors: Bhattacharya Bishnupriya , Roy Polly
Published: August 2008

Bluetongue virus (BTV) is a nonenveloped double-stranded RNA virus belonging to the family
Reoviridae
. The two outer capsid proteins, VP2 and VP5, are responsible for virus entry. However, little is known about the roles of these two proteins, particularly VP5, in virus trafficking and assembly. In this study, we used density gradient fractionation and methyl beta cyclodextrin, a cholesterol-sequestering drug, to demonstrate not only that VP5 copurifies with lipid raft domains in both transfected and infected cells, but also that raft domain integrity is required for BTV assembly. Previously, we showed that BTV nonstructural protein 3 (NS3) interacts with VP2 and also with cellular exocytosis and ESCRT pathway proteins, indicating its involvement in virus egress (A. R. Beaton, J. Rodriguez, Y. K. Reddy, and P. Roy,
Proc. Natl. Acad. Sci. USA
99:13154-13159, 2002; C. Wirblich, B. Bhattacharya, and P. Roy
J. Virol
.
80
:460-473, 2006). Here, we show by pull-down and confocal analysis that NS3 also interacts with VP5. Further, a conserved membrane-docking domain similar to the motif in synaptotagmin, a protein belonging to the SNARE (soluble
N
-ethylmaleimide-sensitive fusion attachment protein receptor) family was identified in the VP5 sequence. By site-directed mutagenesis, followed by flotation and confocal analyses, we demonstrated that raft association of VP5 depends on this domain. Together, these results indicate that VP5 possesses an autonomous signal for its membrane targeting and that the interaction of VP5 with membrane-associated NS3 might play an important role in virus assembly.
In Vitro and In Vivo Properties of Adenovirus Vectors with Increased Affinity to CD46
Authors: Wang Hongjie , Liu Ying , Li ZongYi , Tuve Sebastian , Stone Daniel , Kalyushniy Oleksandr , Shayakhmetov Dmitry , Verlinde Christophe L. M. , Stehle Thilo , McVey John , Baker Andrew , Peng Kah-Whye , Roffler Steve , Lieber André
Published: August 2008

Gene transfer vectors containing adenovirus (Ad) serotype 35 (Ad35) fibers have shown promise for cancer and stem cell gene therapy. In this study, we attempted to improve the in vitro and in vivo infection properties of these vectors by increasing their affinity to the Ad35 fiber receptor CD46. We constructed Ad vectors containing either the wild-type Ad35 fiber knob (Ad5/35) or Ad35 knob mutants with 4-fold- and 60-fold-higher affinity to CD46 (Ad5/35+ and Ad5/35++, respectively). In in vitro studies with cell lines, the higher affinities of Ad5/35+ and Ad5/35++ to CD46 did not translate into correspondingly higher transduction efficiencies, regardless of the CD46 receptor density present on cells. However, in vivo, in a mouse model with preestablished CD46
high
liver metastases, intravenous injection of Ad5/35++ resulted in more-efficient tumor cell transduction. We conclude that Ad5/35 vectors with increased affinity to CD46 have an advantage in competing with non-CD46-mediated sequestration of vector particles after intravenous injection.
The Reverse Transcriptase of the Tf1 Retrotransposon Has a Specific Novel Activity for Generating the RNA Self-Primer That Is Functional in cDNA Synthesis
Authors: Hizi Amnon
Published: August 2008

The Tf1 retrotransposon of
Schizosaccharomyces pombe
represents a group of eukaryotic long terminal repeat (LTR) retroelements that, based on their sequences, were predicted to use an RNA self-primer for initiating reverse transcription while synthesizing the negative-sense DNA strand. This feature is substantially different from the one typical to retroviruses and other LTR retrotransposons that all exhibit a tRNA-dependent priming mechanism. Genetic studies have suggested that the self-primer of Tf1 can be generated by a cleavage between the 11th and 12th bases of the Tf1 RNA transcript. The in vitro data presented here show that recombinant Tf1 reverse transcriptase indeed introduces a nick at the end of a duplexed region at the 5′ end of Tf1 genomic RNA, substantiating the prediction that this enzyme is responsible for generating this RNA self-primer. The 3′ end of the primer, generated in this manner, can then be extended upon the addition of deoxynucleoside triphosphates by the DNA polymerase activity of the same enzyme, synthesizing the negative-sense DNA strand. This functional primer must have been generated by the RNase H activity of Tf1 reverse transcriptase, since a mutant enzyme lacking this activity has lost its ability to generate the self-primer. It was also found here that the reverse transcriptases of human immunodeficiency virus type 1 and of murine leukemia virus do not exhibit this specific cleavage activity. In all, it is likely that the observed unique mechanism of self-priming in Tf1 represents an early advantageous form of initiating reverse transcription in LTR retroelements without involving cellular tRNAs.
DARK FIXATION OF C14O2 BY OBLIGATE AND FACULTATIVE SALT MARSH HALOPHYTES
Authors: Webb Kenneth L. , Burley J. W. A.
Published: August 2008

After dark fixation of C14O2 by salt marsh obligate halophytes, most of the 80% ethanol-soluble label appeared in the amino acid fraction. Species tested were Batis maritima L., Salicornia europaea L., Salicornia virginica L., and Borrichia frutescens (L.) D.C.A time study was made of the dark fixation products of C14O2 by Spartina alterniflora Loisel, a facultative halophyte, cultured with and without NaCl in the nutrient medium. In this species the greater proportion of label was recovered from amino acids (principally aspartic and glutamic acids) at times of 1 hour and less, the pattern changing to favor organic acids at longer times, mainly malic acid in NaCl-free plants. The shift to organic acids was slower in plus NaCl plants with aconitic and an unidentified acid appearing along with malic as the principal labelled acids.NaCl reduced the rate of C14O2 assimilation by Spartina alterniflora. Initially, the fixation pattern resembled that of obligate halophytes, becoming more like that of terrestial plants (glycophytes) after 1 hour.
THE ABSENCE OF ELASTIC DEFORMATION IN DRIED BENT CELLULOSE MICROFIBRILS IN PLANT CELL WALLS
Authors: Colvin J. Ross
Published: August 2008

A small fraction of individual cellulose microfibrils in plant cell walls show appreciable bending along a portion of their length in a plane tangential to the cell surface. Segments of such curved microfibrils from transverse sections of Avena coleoptile epidermal or parenchyma cells do not straighten when they are freed from the constraints imposed by adjacent microfibrils, amorphous cell wall constituents, or the embedding medium. The curvature of these segments is not affected by immersion in cold water for 30 minutes, in hot water for 10 minutes, or in steam at 100° for 10 minutes. The results indicate that there is no elastic deformation of bent cellulose microfibrils in dried plant cell walls. The curvature of the microfibrils in the absence of elastic deformation suggests either (a) that cellulose microfibrils may be synthesized in a bent strain-free condition or (b) that cellulose microfibrils are synthesized in a straight form, followed by elastic deformation with subsequent release of strain by recrystallization on drying.
PHYLOGENETIC STUDIES OF ANEMONE STYLOSA
Authors: Boraiah G.
Published: August 2008

A collection of the allotetraploid Anemone stylosa Nelson from Heliotrope Mts., Gunnison, Utah, was successfully crossed with A. multifida Poir. (tetraploid) and the diploids A. riparia Fern., A. virginiana L., A. silvestris L., and A. pavonina Lam. The karyotype of A. stylosa resembles that of A. multifida except for modifications of chromosome VII in the “large set” and chromosome IV in the “small set”. Meiotic analysis in A. stylosa × A. multifida hybrids indicates that these modifications are due to a chromosome interchange and that this is the only detectable chromosome rearrangement between the two species.Analysis of the crosses with the diploids corroborates these conclusions and suggests that the donor of the “large-chromosome” set of A. stylosa had the A. riparia karyotype rather than the A. virginiana one. A. stylosa may have originated as a variant of A. multifida in which an interchange became established homozygously.
PATHOGENIC FUNGI ASSOCIATED WITH A BARK BEETLE ON ALPINE FIR
Authors: Molnar A. C.
Published: August 2008

Unexplained mortality associated with attacks of the western balsam bark beetle (Dryocoetes confusus Sw.) in alpine fir (Abies lasiocarpa (Hook.) Nutt.) was found to be caused by a beetle–fungus complex. Not all trees attacked were killed, but surviving trees were left with lesions which provided potential entrance courts for decay fungi. Four closely related fungi, isolated from necrotic lesions centered at beetle bore holes, were shown by inoculation to be pathogenic. Ceratocystis dryocoetidis Kendrick and Molnar was the most virulent of these fungi on the basis of the size of lesions produced. C. dryocoetidis caused cambial and inner bark necrosis, while the other three fungi produced necrosis and blue staining of the sapwood.
EFFECTS OF TRANSPLANT INJURY AND NEMATODES ON INCIDENCE OF VERTICILLIUM WILT OF EGGPLANT
Authors: Mountain W. B. , McKeen C. D.
Published: August 2008

The fungus Verticillium dahliae apparently utilizes injured cortical tissue to reach the vascular elements in eggplant roots. The two major sources of such root injury in sandy soils of Ontario are the damage caused mechanically in the transplanting of the seedlings to the field and the root lesions caused by the nematode Pratylenchus penetrans. Transplant injury may be the more important factor early in the season and nematode injury later in the season. The effect of either of these two factors, acting independently, on incidence of disease, however, appears to be about the same.
MORPHOLOGY OF CERATOCYSTIS FIMBRIATA IN ASPEN
Authors: Zalasky H.
Published: August 2008

Additional information on the morphology of Ceratocystis fimbriata and its distribution is provided.
STUDIES ON THE CHITAN (CHITIN: POLY-N-ACETYLGLUCOSAMINE) FIBERS OF THE DIATOM THALASSIOSIRA FLUVIATILIS HUSTEDT: I PRODUCTION AND ISOLATION OF CHITAN FIBERS
Authors: McLachlan J. , McInnes A. G. , Falk Michael
Published: August 2008

Growth of the planktonic, euryhaline diatom (Bacillariophyceae) Thalassiosira fluviatilis, both in nature and in culture, is accompanied by the production of a large amount of extracellular "mucilage". This mucilagenous condition is due to the formation of long, narrow fibers, composed of a number of microfibrils, which originate from the marginal and central pores in the silica valves. These fibers, previously referred to as mucilage or slime threads, were found upon hydrolysis to be composed entirely of glucosamine residues. Evidence will be presented in a subsequent paper (20) to show that these fibers consist entirely of pure, crystalline poly-N-acetyl-D-glucosamine linked by β-(1→4) bonds. This polymer has been given the systematic name chitan to distinguish it from chitin as isolated from other sources. This is the first report of the occurrence of this glycan in diatoms, and in a pure crystalline state in nature. The chitan was localized in the extracellular fibers, and was not found as part of the protoplasmic constituents. Approximately 18% of the nitrogen added to the culture medium was incorporated into the chitan fibers, which, in turn, comprised 31–38% of the cellular material (including the silica) of this diatom. Methods of production and isolation of the fibers are described, together with a discussion of the nature of the fibers as derived from light and electron microscopic observations. The presence of chitin in other algae also is discussed.
RHYTHMIC FLOWERING RESPONSES AND PHYTOCHROME CHANGES IN A SELECTION OF CHENOPODIUM RUBRUM
Authors: Cumming Bruce G. , Hendricks Sterling B. , Borthwick H. A.
Published: August 2008

Flowering of Chenopodium rubrum L., selection 374, was examined with respect to an endogenous circadian rhythm, the state of phytochrome, and the result of changing the form of phytochrome during a single dark period of 2 to 96 hours interrupting continuous light. Darkness was imposed either 4 or 5 days after seeds were placed on moist filter paper in Petri dishes.The following working hypothesis, which is partly retrospective, is projected to explain the main features of the experimental results. Flowering is controlled by a product of the enzymatic action of the far-red absorbing form of phytochrome (Pfr) on a single but unknown substrate. In acting, Pfrfinally reverts to the inactive red-absorbing form of phytochrome (Pr) or is changed from the Pfrform in some other way. The available substrate, if not utilized by Pfraction, is soon depleted by other reactions. The substrate for Pfraction is low during the skotophile but high during the photophile phases. The significant time for phasing is the beginning of darkness. The initial substrate supply appears to be derived from the preceding light period but some time in the region of the 9th to 12th hour of darkness a significant rhythmic change of substrate starts up. The dependence of flowering on the time that darkness is interrupted by light is directly related to a rhythmic change in the optimum Pfrlevel required for the processes leading to flowering.The role of the endogenous rhythm in flowering under natural conditions is questioned. Similarities that are shown in the control of flowering, whether the display is governed by an endogenous rhythm or by a daily photoperiodic cycle, indicate that phytochrome acts as a "pacemaker". It is suggested that the distinct ecotypic populations of C. rubrum that differ in flowering response have dissimilar levels and rates of supply of substrate for phytochrome action. In C. rubrum-374, complete reversion or loss of Pfrdoes not occur during a long dark period of 72 hours at 20 °C, but Pfrdoes decrease to low levels.A hydrodynamic system is discussed as an analogy to rhythmic flowering response.
THE SYMBIOTIC FUNGI OF CERTAIN AMBROSIA BEETLES IN BRITISH COLUMBIA
Authors: Funk A.
Published: August 2008

The symbiotic fungi of three ambrosia beetles found in British Columbia have been cultured and identified. Monilia ferruginea Mathiesen-Käärik, Monilia brunnea Verrall, and Tuberculariella ambrosiae n. sp. are the symbiotic fungi of Trypodendron lineatum Oliv., Monarthrum scutellare LeConte, and Platypus wilsoni Swaine, respectively. Descriptions of these fungi are given and their phylogeny discussed.
BRYOPHYTE SUBFOSSILS OF A LATE-GLACIAL DEPOSIT FROM THE MISSOURI COTEAU, SASKATCHEWAN
Authors: Vries B. de , Bird C. D.
Published: August 2008

Bryophyte and associated macro-subfossils were recovered from a kettle located in prairie southwest of Moose Jaw in the Missouri Coteau of southern Saskatchewan. The higher plants were discussed in an earlier paper.Three samples taken from the organic layer gave C14 datings ranging from 11,650 ± 150 to 10,270 ± 150 B.P.Sixteen species and one variety of Musci were recovered. Eleven of these were found in the lowermost zone at a depth of 510–450 cm. This zone was composed of bryophytes and higher plants characteristic of a modern Picea forest. Fifteen bryophyte taxa were recovered from the middle zone at a depth of 450–290 cm. The macro-subfossils in this zone are typical of a present-day Populus–Picea forest. No bryophytes were found in the upper layer, 290–280 cm characterized by higher plant macro-subfossils and pollen typical of a modern Picea forest.All bryophytes recovered belong to present-day taxa; however, many of the boreal species are not now found in the region as the southern margin of the boreal forest is now 200 miles to the north.
NEW TAXA AND NOMENCLATURAL CHANGES WITH RESPECT TO THE FLORA OF THE QUEEN CHARLOTTE ISLANDS, BRITISH COLUMBIA
Authors: Calder James A. , Taylor Roy L.
Published: August 2008

One new species and eight new subspecies are described; 43 nomenclatural changes are proposed. New entities are Geum schofieldii Calder & Taylor, Calamagrostis purpurascens ssp. tasuensis Calder & Taylor, Carex leptalea ssp. pacifica Calder & Taylor, Lloydia serotina ssp. flava Calder & Taylor, Viola biflora ssp. carlottae Calder & Taylor, Cassiope lycopodioides ssp. cristapilosa Calder & Taylor, Mimulus guttatus ssp. haidensis Calder & Taylor, Pedicularis pennellii ssp. insularis Calder & Taylor, and Senecio cymbalarioides ssp. moresbiensis Calder & Taylor.
STUDIES ON THE BIOSYNTHESIS OF AMARANTHIN
Authors: Garay A. S. , Towers G. H. N.
Published: August 2008

L-Tyrosine was found to be a good precursor of the betacyanin amaranthin in Amaranthus sp. Molten Fire. Administration of tyrosine to seedlings increased the pigment content by almost 100% and radioactive tyrosine was found to be incorporated in the pigment. DOPA was not as effective as tyrosine. L-Phenylalanine and a number of other phenyl derivatives without phenolic hydroxyl groups inhibited amaranthin biosynthesis. The system responsible for amaranthin biosynthesis from tyrosine or DOPA requires light, older seedlings requiring more light than younger ones.
THE EFFECTS OF GIBBERELLIC ACID AND CYCOCEL ON THE GROWTH OF CULTURED LEAF TISSUE
Authors: Bristow J. Michael
Published: August 2008

Meristematic sections of Pteris cretica var. wimsetti leaves were cultured in various nutrient media. Gibberellic acid (GA), in the presence of sucrose, brought about a significant increase in area compared with controls over a 4-week period. GA also prolonged meristematic activity for up to 8 months, the tissue increasing many times in area and dry weight during this interval. GA significantly increased total cell number, while having no effect on the size of individual epidermal cells. Cycocel ((2-chloroethyl) trimethylammonium chloride) strongly inhibited the growth of leaf sections, but this inhibition was completely reversed by GA. The possible role of gibberellins in leaf morphogenesis is discussed.
EFFECT OF TIME OF DAY, A PARASITIC FUNGUS, AND A GENETIC MUTATION ON RATE OF PHOTOSYNTHESIS IN THE LOWBUSH BLUEBERRY
Authors: Hall I. V. , Forsyth F. R. , Lockhart C. L. , Aalders L. E.
Published: August 2008

The apparent rate of photosynthesis in the lowbush blueberry was measured, at four periods of the day, on leaf disks in Warburg flasks and with the use of Pardee's CO2 buffers. Significant differences were found in rates of O2 evolution at the four different periods. Oxygen evolution was greatest in the early morning when reducing sugars and starch levels were lowest. By early afternoon when starch and reducing sugar levels were much greater in the leaf disks the rate was the lowest.Leaf disks infected with Exobasidium vaccinii had a lower rate of apparent photosynthesis than normal leaves of the same clone. Disks cut from normal leaves of Vaccinium angustifolium had a higher rate of apparent photosynthesis than those of a variegated mutant. The leaves of the mutant were significantly smaller and seedlings of the mutant type grew more slowly than normal ones of the same cross. For these reasons lowbush blueberry plants of the mutant type or having the red-leaf disease are at a distinct disadvantage in nature.
PHOTOSYNTHESIS IN ALGAE: I. ACCUMULATION PRODUCTS IN THE RHODOPHYCEAE
Authors: Majak W. , Craigie J. S. , McLachlan J.
Published: August 2008

Photosynthesis in14CO2was observed in 12 algal species from six rhodophycean orders. Rates of CO2uptake ranged from 0.5 to 4.0 mg h−1 × g−1on a fresh weight basis. Excretion of new photosynthate was not important in macrophytes whereas 4.4% of the14C fixed by Porphyridium sp. was excreted in 2 hours.Members of the Ceramiales could be distinguished by their relatively large accumulation of14C in the alcohol-insoluble fraction.In most species, alanine, glutamic and aspartic acids, serine, and glycine were the most radioactive soluble amino acids. The chief soluble radioactive carbohydrate was floridoside except in the Ceramiales, in which it was low or absent. Batrachospermum, which contained14C-trehalose, also lacked floridoside.14C-Mannitol was recorded in nine species and14C-glucose in two others. Several unknown substances were detected on chromatograms.
ENZYMES OF MARINE ALGAE: II. ISOLATION AND IDENTIFICATION OF 3-HYDROXYTYRAMINE AS THE PHENOLASE SUBSTRATE IN MONOSTROMA FUSCUM
Authors: Tocher R. D. , Craigie J. S.
Published: August 2008

3-Hydroxytyramine (dopamine; 3, 4-dihydroxyphenylethylamine) is reported for the first time as an algal constituent. It was isolated and crystallized in approximately 0.3% of the fresh weight of the green alga, Monostroma fuscum. The identity was established by the comparison of its physical and chemical properties with those of an authentic specimen. 3-Hydroxytyramine is the principal phenol and the natural substrate for phenolase in this organism.
APICAL GROWTH OF POPULUS SPP.: I. SEQUENTIAL PATTERN OF INTERNODE, BUD, AND BRANCH LENGTH OF YOUNG INDIVIDUALS
Authors: Maini J. S.
Published: August 2008

Young individuals of Populus tremuloides Michx., P. grandidentata Michx., and P. balsamifera L. were studied at one locality in southern Ontario. The sequential patterns of apical growth as indicated by their internode, bud, and branch length are consistent and characteristic within but differ between each of the three species. The length of bud was closely correlated with the length of branch that subsequently developed from it. Angles of divergence and pattern of the primary branch length were also characteristic of each species and resulted in different crown forms. The study indicates that these sequential patterns are genetically controlled.
EFFECT OF WATER STRESS ON RESPIRATION OF WHEAT
Authors: Kaul Rudolf
Published: August 2008

A simple method of subjecting wheat seedlings to progressive water stress and of measuring the respiration rates is described. Slight water deficits increased CO2output by about 20%, and more severe water stress decreased it by about 50%. Water stress caused significant changes in the concentrations of malate and citrate and of an unknown organic acid. Water stress strikingly decreased the level of malate in the roots and increased it in the shoots. It is suggested that the decrease in respiration caused by water stress cannot be attributed to an increased rate of dark fixation of carbon dioxide.
THE PHYSIOLOGY OF HOST–PARASITE RELATIONS: XVI. FINE STRUCTURE OF THE NUCLEUS IN THE RUST-INFECTED MESOPHYLL CELLS OF WHEAT
Authors: Manocha M. S. , Shaw Michael
Published: August 2008

The nuclei in rust-infected mesophyll cells of Little Club wheat were examined by electron microscopy. There was a marked increase in the electron density of the diffuse, interchromatin regions of the nuclei at a stage in rust development (8 days after inoculation) at which two- to three-fold increases in RNA are known to occur. In the late stages of rust development (20 to 23 days after inoculation) the interchromatin material disappeared and the dense chromatin disintegrated.
THE PHYSIOLOGY OF HOST-PARASITE RELATIONS: XVII. ACID-SOLUBLE NUCLEOTIDES IN RUST-INFECTED AND SENESCING WHEAT LEAVES
Authors: Quick W. A. , Shaw Michael
Published: August 2008

Acid-soluble nucleotides in senescing wheat leaves tended to decrease with time in a manner similar to the decline in RNA.2 Little change was apparent in the free nucleotide: RNA nucleotide ratio. Treatment with kinetin reduced, but did not prevent the loss of soluble nucleotides. The greatest losses occurred in the nucleoside diphosphates. Rust infection increased each of the soluble nucleotides even more rapidly than it increased RNA content. Rust uredospores, themselves, appeared to possess a large soluble nucleotide pool. Uridine and adenosine derivatives were the only nucleotides consistently found. Uredospores and rust-infected leaves differed from uninfected leaves in possessing a large amount of a UDP-N-acetylglucosamine complex. The results are discussed in relation to previous measurements of RNA in senescing and rust-infected leaves.
SHOOT GROWTH CHARACTERISTICS OF HETEROPHYLLOUS WOODY PLANTS
Authors: Kozlowski T. T. , Clausen J. Johanna
Published: August 2008

Observations were made on relationships between contents of winter buds and subsequent shoot growth characteristics of Betula papyrifera, B. alleghaniensis, Populus tremuloides, and P. grandidentata. In both species of Betula, winter buds expected to produce long shoots contained both embryonic leaves and leaf primordia. Both early and late leaves were produced by growing shoots. In contrast, in both species of Populus all leaves produced on the observed shoots appeared at bud break and matured rapidly. Evidence for a variety of patterns and degrees of dependency of expanding shoot systems on reserve foods and currently produced carbohydrates is presented. Shoot elongation of species with shoots fully preformed in the winter bud utilizes large amounts of reserve carbohydrates. In growth of long shoots of heterophyllous species considerable current photosynthate appears to be used. In Betula the contribution of early and late leaves to shoot growth differed markedly. Covering of early leaves before mid-June inhibited shoot growth. The presence of normally growing early leaves was essential for normal shoot development and survival.
HEART ROT OF JACK PINE IN ONTARIO: II. LABORATORY STUDIES ON THE PATHOGENICITY AND INTERRELATIONSHIPS OF THE PRINCIPAL HEARTWOOD-INHABITING FUNGI
Authors: Basham J. T.
Published: August 2008

Two Basidiomycetes, Fomes pini (Fr.) Karst. and Peniophora pseudo-pini Weres. & Gibson, and three microfungi (Ascomycetes), Tympanis hypopodia Nyl., Retinocyclus abietis (Crouan) Groves & Wells, and a member of the Coryne sarcoides complex, are the fungi most frequently isolated from the heartwood of living jack pine (Pinus banksiana Lamb.) in the Province of Ontario. Of these, only F. pini is consistently associated with decayed wood. In laboratory tests all five caused significant weight losses in jack pine heartwood samples, and all but the C. sarcoides complex appreciably altered the color of the wood. T. hypopodia was exceedingly antagonistic towards F. pini, both in malt agar culture and when inoculated in advance of F. pini in jack pine wood samples. The activity of P. pseudo-pini in the test samples was reduced slightly by the prior establishment of T. hypopodia and the C. sarcoides complex, but was stimulated somewhat by the presence of R. abietis. The presence of the C. sarcoides complex in jack pine samples resulted in a moderate increase in the activity of F. pini.In some cases competitive interactions among heartwood-inhabiting fungi may partly explain the marked variability in defectiveness frequently observed among individual trees in forest stands.
VERTICILLIUM CHLAMYDOSPORIUM AND ITS RELATIONSHIPS TO DIHETEROSPORA, STEMPHYLIOPSIS, AND PAECILOMYCES
Authors: Barron G. L. , Onions Agnes H. S.
Published: August 2008

Two hyphomycetes with similar aleuriospore states are considered. One, with a Verticillium phialospore state, was validly published as Verticillium chlamydosporium Goddard; Stemphyliopsis ovorum Petch and Diheterospora heterospora Kamyschko are later synonyms. The other has a Paecilomyces phialospore state and was validly published as Diheterospora catenulata Kamyschko. The two species show similarities in cultural habit, morphology, and biological specialization and it is proposed that they be considered under one genus, viz. Diheterospora.
RESPIRATION OF INTACT CELLS OF A LOW-TEMPERATURE BASIDIOMYCETE
Authors: Ward E. W. B.
Published: August 2008

Conventional manometric procedures were used to measure oxygen uptake and carbon dioxide evolution by cells of a low-temperature basidiomycete. Total respiration was lowest and, relatively, endogenous respiration was highest in old cells. During starvation, endogenous respiration decreased but did so most rapidly in young cells. Maximum response to exogenous glucose was obtained from young cells after starvation. The respiratory quotient of endogenous respiration fell from 1.0 to approximately 0.7 during starvation, indicating a change in endogenous substrate. Conversely the respiratory quotient for exogenous respiration of added glucose increased with the starvation period. The level of oxidative assimilation of glucose was shown to be high (80-90%) and evidence was obtained that exogenous glucose did not suppress endogenous respiration.The optimum temperature for oxygen uptake was 25 °C, below which the Q10 was approximately 2. At 30 °C the rate, while initially highest, decreased during the 6-hour incubation period.The fungus utilized various compounds as carbon sources, but not sucrose in short-term experiments. Glucose, but not xylose was fermented, although the ratio of carbon dioxide to ethanol was not 1:1. Inhibition by fluoride, arsenite, iodoacetate, fluoroacetate, and malonate suggested that both glucose and xylose are respired at least in part by the Embden-Meyerof pathway and the tricarboxylic acid cycle. Endogenous respiration was only slightly affected by these inhibitors.
SYNTHESIS OF MYCORRHIZAE ON EXPLANTS OF THE ROOT HYPOCOTYL OF PINUS SYLVESTRIS L.
Authors: Fortin J. André
Published: August 2008

A method of growing excised root cultures of leguminous plants was modified for the culture of excised roots of Pinus sylvestris L. The inclusion of a portion of hypocotyl on the expiants from the seedlings was found essential to obtain sustained growth of the root. With such explants, typical ectotrophic mycor-rhizae were obtained upon inoculation with Amanita rubescens (Pers. ex Fr.) Quel.
THE SPECTRAL COMPOSITION OF NEAR ULTRAVIOLET AND VISIBLE RADIATION BENEATH FOREST CANOPIES
Authors: Vézina P. E. , Boulter D. W. K.
Published: August 2008

The spectral composition of near ultraviolet and visible radiation in the open and in pure stands of Pinus resinosa Ait. and Acer saccharum Marsh was determined for cloudless, hazy, and overcast conditions. In the open, the spectral composition of light on clear and overcast days differed significantly only in quantity. Beneath the forest canopy the quality of light was changed greatly with respect to the open when the incoming radiation was direct sunlight. The selectivity of absorption and reflection in the visible spectrum by the deciduous canopy was shown quite conclusively while the conifer canopy appeared to be fairly neutral. On overcast days and during the leafless period of the deciduous canopy, transmission of the incident radiation was very high while the change in light quality appeared to be slight. The results are discussed in relation to the light-intercepting capacities of the leaves of the different species, the light climate in the forest, and silvicultural management.