bluuebunny/crossref_metadata_2025 huggingface dataset:
Tissue-based Assay for Ornithine Decarboxylase to Identify Patients Likely to Respond to Difluoromethylornithine
Authors: Levin Victor A. , Jochec Jacob L. , Shantz Lisa M. , Koch Patricia E. , Pegg Anthony E.
Published: October 2004

In a previous publication, we showed that a clinical trial of DL-α-difluoromethyl ornithine (DFMO), in combination with PCV (procarbazine, CCNU, vincristine) increased survival of patients with anaplastic gliomas (WHO III) but not glioblastoma multiforme (WHO IV). We believe that treatment outcome (survival) is inversely related to tumor ornithine decarboxylase (ODC) levels. To prove this, we needed to develop an assay to quantify ODC levels in formalin-fixed tumor tissues, which would enable a retrospective study of tumor biopsy specimens from the landmark clinical trial. We developed an assay using a specific polyclonal antibody coupled to an Alexa fluorescent dye. Transgenic MHC-ODC mice with differing levels of ODC in heart muscle were used to establish the relationship between mean gray-scale intensity and enzymatic ODC activity. We found a direct relationship between mean gray-scale intensity of the ODC antibody coupled to Alexa 647 dye and enzymatic activity. Preliminary analysis of a human glioma tissue array shows that tumor-specific variations in levels of ODC can be semiquantitated. We show that mean gray-scale intensity of astrocytoma:glioblastoma is 1:6 and of anaplastic astrocytoma:glioblastoma is 1:4. We also compared the intensity of antibody to Ki67 coupled with phyco-erythrin simultaneously in cells but failed to see a relationship that crossed histologies. We conclude that we can measure levels of ODC in formalin-fixed tumor tissue using an antibody to ODC coupled to Alexa 647 dye, and this will enable us to conduct a future study to correlate survival of patients with gliomas of different histologies treated with DFMO to tumor ODC levels.
GLUT2 Immunoreactivity in Gomori-positive Astrocytes of the Hypothalamus
Authors: Young John K. , McKenzie James C.
Published: October 2004

A specialized subtype of astrocyte, the Gomori-positive (GP) astrocyte, is unusually abundant and prominent in the arcuate nucleus of the hypothalamus. GP astro-cytes possess cytoplasmic granules derived from degenerating mitochondria. GP granules are highly stained by Gomori's chrome alum hematoxylin stain, by the Perl's reaction for iron, or by toluidine blue. The source of the oxidative stress causing mitochondrial damage in GP astrocytes is uncertain, but such damage could arise from the oxidative metabolism of glucose transported into astrocytes by high-capacity GLUT2 glucose transporters. In accord with this hypothesis, the reported anatomical distribution of astrocytes staining positively for GLUT2 glucose transporters closely matches that of GP astrocytes. To examine whether or not these two staining procedures detect the same population of astrocytes, immunocytochemistry was performed on semithin sections to detect GLUT2 protein and sections were then stained with toluidine blue to detect GP granules. It was determined that GP astrocytes are frequently immunoreactive for the GLUT2 transporter protein. These data support the possibility that GP astrocytes may have an important influence upon the reactivity of the hypothalamus to glucose and that a specialized glucose metabolism may in part underlie the development of mitochondrial abnormalities in hypothalamic GP astrocytes.
Eccentric Localization of Osteocytes Expressing Enzymatic Activities, Protein, and mRNA Signals for Type 5 Tartrate-resistant Acid Phosphatase (TRAP)
Authors: Nakano Yukiko , Toyosawa Satoru , Takano Yoshiro
Published: October 2004

Enzymatic activity of type 5 tartrate-resistant acid phosphatase (TRAP) has been regarded as one of the reliable markers for osteoclasts and their precursors. The presence of TRAP activity in osteocytes near the bone resorbing surface has also been pointed out in some reports. However, the significance of TRAP reactions in osteocytes remains controversial and, in fact, there is no agreement as to whether the histochemical enzyme reactions in osteocytes represent the TRAP enzyme generated by the respective osteocytes or is a mere diffusion artifact of the reaction products derived from the nearby osteoclasts. Current histochemical, immunohistochemical, and in situ hybridization studies of rat and canine bones confirmed TRAP enzyme activity, TRAP immunoreactivity, and the expression of Trap mRNA signals in osteocytes located close to the bone-resorbing surface. TRAP/Trap-positive osteocytes thus identified were confined to the areas no further than 200 üm from the bone-resorbing surface and showed apparent upregulation of TRAP/Trap expression toward the active osteoclasts. Spatial and temporal patterns of TRAP/Trap expression in the osteocytes should serve as a valuable parameter for further analyses of biological interactions between the osteocytes and the osteoclasts associated with bone remodeling.
High-resolution Visualization of the Microbial Glycocalyx with Low-voltage Scanning Electron Microscopy: Dependence on Cationic Dyes
Authors: Erlandsen Stanley L. , Kristich Christopher J. , Dunny Gary M. , Wells Carol L.
Published: October 2004

The microbial glycocalyx is composed of a variety of polyanionic exopolysac-charides and plays important roles in microbial attachment to different substrata and to other cells. Here we report the successful use of low-voltage scanning electron microscopy (LVSEM) to visualize the glycocalyx in two microbial models ( Klebsiella pneumoniae and Enterococcus faecalis biofilms) at high resolution, and also the dependence on fixation containing polycationic dyes for its visualization. Fixation in a paraformaldehyde-glutaral-dehyde cocktail without cationic dyes was inadequate for visualizing the glycocalyx, whereas addition of various dyes (alcian blue, safranin, and ruthenium red) to the aldehyde cocktail appeared necessary for stabilization. The cationic dyes varied in size, shape, and charge density, and these factors appeared responsible for different phenotypic appearances of the glycocalyx with each dye. These results suggest that aldehyde fixation with cationic dyes for high-resolution LVSEM will be a useful tool for investigation of microbial biofilms as well as investigation of the extent and role of the glycocalyx in microbial attachment to surfaces.
Cellular UV Microspectrophotometric Investigation of Sapelli Heartwood (Entandrophragma cylindricum Sprague) from Natural Provenances in Africa
Authors: Kleist Gunnar , Bauch Josef
Published: October 2004

The colour of Sapelli heartwood (Entandrophragma cylindricum Sprague) is variable depending on habitat. In recent years an unusual pinkish-brown colour has been observed in commercial sawn timber of this species from Central Africa. Initial studies of Sapelli heartwood samples from various provenances have furthermore demonstrated pronounced differences in its decay resistance.

Heartwood extractive composition varies considerably between provenances. Samples of Sapelli heartwood from the Central African Republic (RCA) contained 6.4% by weight of extractives compared with 12.5% for those from Cameroon and four other provenances investigated. UV microspectrophotometric analysis of heartwood extractives was used to localise phenolic extractives within wood cell walls and to identify their distribution at tissue level. The S2 and S3 wall layers of vessels and fibres in the heartwood were discriminated from sapwood by their high concentration of non-lignin phenolic extractives. These extractives in the cell walls were also found to be variable. As UV absorption properties show, the vessel and fibre secondary walls of Cameroon heartwood had a considerably higher concentration of extractives in comparison with samples from the RCA. In sapwood, the UV absorption levels for the fibre S2 layer and the vessel S3 layer were independent of the extraction procedure, suggesting the phenolic extractives in this part of the trunk were in low concentrations. Furthermore it is suggested that polyphenols constitute part of the cell wall matrix. The non-extractable phenolic content was found to be independent of provenances as demonstrated by wood from Cameroon and the RCA.

The natural durability of Sapelli heartwood against fungal decay appears to be dependent on the extractive composition and on their concentration in the fibre tissue.
Leeuwenhoek's Observations on the Anatomy of Bark
Authors: Baas Pieter
Published: October 2004

Leeuwenhoek's letter to the Royal Society of 27 March 1705, dealing with the anatomy of bark of cherry, birch, cinnamon, lime and cork oak is reviewed. It contains many detailed observations and illustrations of, i.a., ray dilatation, various types of phloem sclerenchyma, and annual rings in cork. This is another example of Leeuwenhoek's importance as an early plant anatomist.
Seasonal Variations in Endogenous Indole-3-Acetic Acid and Abscisic Acid in the Cambial Region of Pinus densiflora Sieb. et Zucc. Stems in Relation to Earlywood-Latewood Transition and Cessation of Tracheid Production
Authors: Funada R. , Kubo T. , Tabuchi M. , Sugiyama T. , Fushitani M.
Published: October 2004

Seasonal changes in the total amount (measured as ng cm−2) of endogenous indole-3-acetic acid (IAA) and abscisic acid (ABA) in the cambial region of Pinus densiflora Sieb. et Zucc. trees with crowns of different sizes were determined at different stem heights. The total amount of IAA varied seasonally in all trees and at all stem positions, being maximal in early summer (May or July). In a tree with a large crown, the total amount of IAA remained high after peaking and declined in autumn, whereas in a tree with small crown it decreased rapidly after peaking, in particular in the lower stem. The transition from earlywood to latewood occurred concurrently with the decrease in the total amount of IAA after it had peaked, suggesting the involvement of IAA in the control of latewood formation. Cessation of the production of tracheids also paralleled the decline in the total amount of IAA early in the growing season in the lower stem of the tree with a small crown, but not in the tree with a large crown. Thus, other factors in addition to declining IAA seem to be involved in halting the production of the tracheids. The total amount of ABA was lower than that of IAA in all trees and at all stem heights, and changes were not correlated with specific changes during the annual cycle of cambial activity and dormancy.
Immunolocalization of O-Methyltransferase and Peroxidase in Differentiating Xylem of Poplar
Authors: Takeuchi Miyuki , Takabe Keiji , Fujita Minoru
Published: October 2004

Anti-O-methyltransferase (OMT) antiserum was prepared using a part of the OMT-histidine fusion protein expressed in transformed E. coli cells as antigens. Anti-peroxidase antiserum was prepared using artificially synthesized peptides. Immunocytochemistry revealed that OMT and peroxidase are localized in differentiating xylem cells of Populus euramericana. OMT labeling was observed in the cytosol and peroxidase labeling was observed in the ER or near the ER membrane.
Fibre Length and Microfibril Angle in Silver Birch (Betula pendula Roth)
Authors: Bonham V. A. , Barnett J. R.
Published: October 2004

A comparative study was carried out on fibre length and microfibril angle in Betula pendula Roth. Fibre length increased and microfibril angle decreased from pith to bark. Microfibril angle remained constant from the 15th annual ring from the pith, to the outermost ring. Fibre length also reached a maximum length at this point although there were some differences at the 30th ring from the pith.
The Further Chemistry of Ellagic Acid: I. Synthesis of Tetramethylellagic Acid and Associated Polymer Precursors
Authors: Reitze J.D. , Przewloka S.R. , Shearer B.J.
Published: October 2004

A quantitative method for the production of 3,3′,4,4′-tetra-O-methylellagic acid was developed. Ellagic acid was fully methylated under nitrogen and in air using dimethyl sulphate and 25% guanidinium methoxide in N-methyl-2-pyrrolidone. The synthesis of a range of polymer precursors derived from 3,3′,4,4′-tetra-O-methylellagic acid are outlined, including the previously unreported 2,3,4,2′,3′,4′-hexamethoxy-6,6′-diphenoyl-dichloride, 2,3,4,2′,3′,4′-hexamethoxy-6,6′-diisocyanato-diphenyl, 2,3,4, 2′,3′,4′-hexamethoxy-6,6′-diamino-diphenyl, 2,3,4,2′,3′,4′-hexamethoxy-6,6′-dihydroxymethyl-diphenyl and 2,3,4,2′,3′,4′-hexamethoxy-diphenyl-6,6′-dialdehyde.
Relationships between Density, Shrinkage, Extractives Content and Microfibril Angle in Tension Wood from Three Provenances of 10-Year-Old Eucalyptus globulus Labill
Authors: Washusen R. , Ades P. , Evans R. , Ilic J. , Vinden P.
Published: October 2004

Density and microfibril angle (MFA) of tension wood and normal wood were assessed in the sapwood and heartwood, from three provenanaces of 10-year-old Eucalyptus globulus Labill. Density was measured using a modified saturation method that also enabled the calculation of the extractives lost during saturation. Microdensity and MFA were determined by SilviScan 2, a rapid X-ray densitometry and X-ray diffraction system developed at CSIRO. Significant differences were found in density and extractives between provenances and also density between the sapwood and adjacent heartwood from each provenance. This result may explain some of the drying differences between provenances found in an earlier study (Washusen and Ilic 2000). Sapwood samples with high percentages of tension wood fibres had high density and a significant positive correlation was found between microdensity and tension wood fibre percentage. MFA was found to be very low in normal wood in the sapwood, where most tension wood was found, so tension wood could not be identified by MFA. The positive association between tension wood and wood density suggests that caution should be taken when selecting trees for high wood density in tree improvement programs.
Characterization of Residual Lignins from Chemical Pulps of Spruce (Picea abies L.) and Beech (Fagus sylvatica L.) by Analytical Pyrolysis–Gas Chromatography/Mass Spectrometry
Authors: Choi J.-W. , Faix O. , Meier D.
Published: October 2004

Residual lignins have been isolated by enzymatic hydrolysis from sulfite, kraft, ASAM and soda/AQ/MeOH pulps obtained both of spruce and beech wood. The protein content of the samples were in the range of 2 to 61 % and the carbohydrate content fluctuated roughly between 1 and 12 %. Seven of the isolates have been submitted to analytical pyrolysis (Py-GC/MS) aiming at the determination of the lignin composition in terms of 4-hydroxy-phenylpropane, guaiacylpropane, and syringylpropane units, referred to in the following as H, G, and S units. Pyrolysis of proteins leads mainly to phenol, cresol, and indole. Phenol and cresol of protein origin may influence seriously the H content determination of lignins. However, the contribution of protein to this compounds can be corrected successfully based on the intensity of the indole peak in the pyrograms. Nevertheless, the pyrolysis results should not be over-interpreted concerning the H contents in the case of samples heavily contaminated with proteins. As analytical pyrolysis overestimates the S content in a similar manner as the chemical degradation techniques do, an empirical correction equation was used to approximate the “true”" S content. Py-GC/MS gave systematic and reproducible differences between the residual lignins on the one hand, and the MWLs, which have been pyrolysed for comparison, on the other hand. The fingerprinting ability of analytical pyrolysis, the G/S ratios of beech residual lignins, and the unusual properties of ASAM residual lignins with their high S contents are discussed.
Effects of Acetylation and Hydrothermal Treatment on Lignin as Revealed by Cellular UV-Spectroscopy in Norway Spruce (Picea abies [L.] Karst.)
Authors: Sander C. , Koch G.
Published: October 2004

The effect of two different wood modification treatments on the lignin of Norway spruce wood was studied by means of cellular UV-spectroscopy. The modification treatments chosen were acetylation using acetic anhydride and a two step hydrothermal treatment. Small cross sectional thin slides from the wood surface were taken and were subsequently analysed using a UV-micro-spectro-photometer. The modified samples were compared with a non-treated control sample. The results revealed changes in the absorption spectra of lignin after both modification treatments. Spectra of the compound middle lamella (CML) of acetylated wood revealed a decrease in the lignin-specific absorption maximum at 280nm, which is considered to be caused by superficial leaching of lignin due to acetylation. The retarding effect of acetylation on UV-degradation of wood is discussed. In hydrothermal-treated wood the 280nm maximum was increased within the S2 layer. This maximum remained almost unchanged in the CML while a lower maximum was observed at about 330nm. Changes in the chromophoric behaviour of lignin are probably caused by de-masking reactions within the S2 layer resulting from hydrolysis of carbohydrates and side chain reactions. Both treatments lead to a severe decrease in absorption at the lower end of the spectrum towards 250nm which is possibly attributed to changes or even splitting of biphenyls.
Furfural and Hydroxymethylfurfural as By-Products of FORMACELL Pulping
Authors: Lehnen Ralph , Saake Bodo , Nimz Horst H.
Published: October 2004

The formation and stability of furans formed from pentoses and hexoses were studied in acetic acid/formic acid mixtures which are applied in the FORMACELL pulping process. For comparison, acetic acid/water mixtures with and without addition of HCl were included in the study. The investigations demonstrated that furfural can be obtained in high yields from xylose and xylan. Hexoses are converted to hydroxymethylfurfural (HMF), acetoxymethylfurfural (AMF) and furfural. Here, the water content of the reaction mixture influences the ratio of HMF and AMF in the solution. Stability studies revealed that furfural and HMF exhibit a high stability in acetic acid/formic acid mixtures. This explained the high furfural yields previously published for acetic acid pulping. The long-time stability of furans was investigated for 275 days at room temperature. No significant losses occurred suggesting that organic acids act as radical scavengers inhibiting oxidative degradation.
Chemical Structures of (+)-Catechin-Formaldehyde Reaction Products (Stiasny Precipitates) Under Strong Acid Conditions: Part 1. Solid-State 13C-NMR Analysis
Authors: Saito N. , Reilly M. , Yazaki Y.
Published: October 2004

To determine more accurately the amount of polyflavanoids in tannin extracts from radiata pine bark, which react with formaldehyde, it is important to elucidate chemical structures of (﹢)-catechin-formaldehyde reaction products (Stiasny precipitates). The Stiasny value of 106.4% for (﹢)-catechin was obtained from the reaction with formaldehyde under strong acid conditions. This value is almost identical to the value calculated from the Stiasny precipitates, which were formed in the ratio of two molecules of (﹢)-catechin to three molecules of formaldehyde.

The solid-state 13C NMR spectrum was measured to elucidate the structures of the Stiasny precipitates, and analysed on the basis of the chemical shifts of (﹢)-catechin. The NMR results indicate that C-6 and C-8 in the A-ring are bonded by methylene bridges to form polymers, and also form methylene bridges with C2′, C5′ or C6′ in the B-ring of a catechin unit.

Consequently, the reaction products of (﹢)-catechin-formaldehyde under strong acid conditions (Stiasny precipitates) are (﹢)-catechin-polymers, which consist of two moles of (﹢)-catechin and three moles of formaldehyde. The methylene bridges are formed mostly between A-rings, and less frequently, between A- and B-rings and between B-rings of the catechin units.
Non-Wood Fiber as an Alternative to Wood Fiber in Chinas Pulp and Paper Industry
Authors: Hammett A. L. , Youngs Robert L. , Sun Xiufang , Chandra Mudit
Published: October 2004

The pulp and paper industry in China has been growing rapidly as the nation's population and economy have grown. As a result, there has been a huge demand for pulp and paper raw materials. China has a long tradition for using non-wood raw materials for pulp and paper due to its limited forest resources and rich supply of agricultural residues and non-wood plants. Agricultural residues, such as rice straw and wheat straw, are traditional raw materials for China's paper industry. Massive plantation of bamboo provides an increasingly important source of raw material for pulp and paper. Problems with non-wood fiber include collection and transportation, storage and handling, washing, bleaching, papermaking, and chemical recovery. Small mills, primary users of non-wood fiber, are typically deficient in pollution control and subject to government closure. This paper reviews non-wood fibers commonly used in China's pulp and paper industry. By increased knowledge of use of non-wood fibers, wood suppliers can plan for access to the growing Chinese market.
Biological Control of Blue Stain in Pulpwood: Mechanisms of Control used by Phlebiopsis gigantea
Authors: Behrendt Chad J. , Blanchette Robert A.
Published: October 2004

Phlebiopsis gigantea, a white-rot fungus currently being tested in biological processing applications for the pulp and paper industry, was shown to effectively inhibit blue stain fungi in both laboratory and field trials. Inoculation of logs withP. giganteashortly after cutting resulted in up to 86% colonization of logs in the laboratory and 100% in field studies. Colonization of logs by blue stain fungi such asOphiostoma piliferumandO. piceaewas greatly reduced or completely inhibited with prior inoculation byP. gigantea. In field studies, blue stain fungi colonized up to 53% of the sapwood and stained as much as 31% of the sapwood in non-inoculated control logs in contrast to 4% colonization and 2% stain in treated logs. Logs inoculated withO. piliferum2 weeks prior to inoculation withP. giganteawere 88% colonized byO. piliferumand had 33% of the sapwood stained after 7 weeks, and 33% colonized and 18% stained after 29 weeks. Scanning electron micrographs ofP. giganteaandO. piliferumhyphae showedP. giganteaparasitizing the blue stain fungus.Phlebiopsis giganteawas shown penetrating and growing adjacent to collapsed and disintegrated blue stain hyphae.Phlebiopsis giganteaalso decolorized sapwood previously stained blue.
Inhibition of the Photodiscoloration of Wood by Butyrylation
Authors: Chang Shang-Tzen , Chang Hui-Ting
Published: October 2004

The lightfastness of butyrylated China fir (Cunninghamia lanceolata var. lanceolata) and maple (Acer
sp.) was evaluated in this study, and its effectiveness was compared with that of acetylated specimens.
The color fading in acetylated China fir and maple woods was reduced to half that of untreated specimens,
after a 24-day UV lightfastness test. The effectiveness of butyrylation on photodiscoloration prevention
in wood was even more pronounced than that with acetylation. With an 18.57% weight percent
gain, butyrylation remarkably inhibited the discoloration of wood following UV irradiation. Based on
infrared spectral analysis, the lignin of both untreated and butyrylated woods deteriorated after exposure
to UV light, but the holocellulose in butyrylated wood was more resistant to the UV light. Furthermore,
results obtained from diffuse reflectance UV-VIS spectral analysis elucidated that the absorption of irradiated
butyrylated wood, in comparison with that of the irradiated but untreated specimens, was lower
in both UV light and visible light regions. It also revealed that the inhibition of photodiscoloration of
wood by butyrylation was caused mainly by a significant reduction of chromophoric derivatives, such as
quinoid compounds, formed on the wood surface.
Lipophilic Extractives from Eucalyptus globulus Pulp during Kraft Cooking Followed by TCF and ECF Bleaching
Authors: Gutiérrez A. , Romero J. , Río J.C. del
Published: October 2004

The chemical composition of lipophilic extractives in paper pulps fromEucalyptus globuluswood during kraft cooking followed by TCF (“totally chlorine free”) and ECF (“elemental chlorine free”) bleaching sequences has been determined by gas chromatography and gas chromatography-mass spectrometry. The chemical analyses revealed that the composition of the lipophilic extractives in pulp after kraft cooking and TCF bleaching with hydrogen peroxide was similar to that ofE. globuluswood extractives, sitosterol and sitosterol esters being the predominant compounds. In contrast, the presence of these compounds was almost negligible in pulp after ECF bleaching with chlorine dioxide and only the saturated sterol stigmastanol, in both free and esterified forms, survived the bleaching.
Determination of Monosaccharide Composition of Eucalyptus globulus Wood by FTIR Spectroscopy
Authors: Rodrigues José , Puls Jürgen , Faix Oskar , Pereira Helena
Published: October 2004

FTIR spectroscopy was used to estimate monosaccharide content in Eucalyptus globulus wood, using
the natural variability of the species for calibration and validation of the method . A total of 38 samples
from 9 year old trees from provenance trials was used. The composition ranged for glucose from 43.2%
to 59.5%, for xylose from 9.4% to 17.8%, for galactose from 0.5% to 5.4%, for mannose from 0% to
2.8%, and for rhamnose from 0.3% to 0.8%, based on extractive-free dry wood. The multivariate analysis
gave in general, better results with increased R2, lower SEC and SEP errors, although the univariate
method also gave good fits with high coefficient of determination (R2) based on remaining data once outliers
were removed. FTIR techniques may be used in large scale breeding programmes to measure wood
monosaccharide composition with considerably less effort and in shorter time than wet-lab methods,
once a reliable calibration has been made for the species.
Acetyl Group Distribution in Acetylated Wood Investigated by Microautoradiography
Authors: Rosenqvist Marie
Published: October 2004

Sapwood of Scots pine (Pinus silvestris L.) was acetylated with 14C- and 3H-labelled acetic anhydride.
The distribution of acetyl groups was investigated with microautoradiography and microautoradiographs
were evaluated with ESEM, Environmental Scanning Electron Microscopy.

The investigation showed that the impregnation of wood with radioisotope-labelled substances provides
a good opportunity to investigate the location of substances covalently bonded to the wood material.
Introduced 14C-labelled acetyl groups show an even distribution in the wood cell wall, with no discernible
concentration gradients at acetylation levels of about 5, 15 and 20% weight gain. 3H-labelled
acetyl groups show an even distribution in the wood cell wall at 15 and 20% weight gain, with no discernible
concentration gradients. At the 5% weight gain level, however, an uneven distribution of 3H-labelled
acetyl groups over the cell wall is observed. Nevertheless, the unevenness is random and no concentration
gradient is discernible at this level.

3H with a relatively high resolution, 0.5–1 μm, compared to 14C with a resolution of 2–5 μm, gives
more accurate information about where exactly the acetyl groups are situated in the wood cell wall.
Acetic anhydride was evenly distributed when a full impregnation procedure was used. The chemical and
physical properties of acetic anhydride allow a uniform penetration into the pine cell wall and a complete
acetylation takes place when the specimens are heated.
Solid State NMR Analysis of β-13C-Enriched Lignocellulosic Material During Light-Induced Yellowing
Authors: Parkås Jim , Paulsson Magnus , Westermark Ulla , Terashima Noritsugu
Published: October 2004

Photoyellowing of lignocellulosic materials has been studied with a new technique based on solid state13C-NMR analysis of13C-enriched DHP in cell wall tissue. The selectively13C-enriched cell wall-dehydrogenation polymer (CW-DHP) was prepared directly on differentiating xylem from spruce (Picea abies) at pH 6.0 by administering β-13C-enriched coniferin in an enzymatic system consisting of glucose oxidase, β-glucosidase, and the naturally occurring water-insoluble enzymes remaining in the cell wall. The bonding pattern of the formed CW-DHP was found to be: 42% β-β, β-5, and β-1 substructures; 36% β-O-4 derived substructures; and 22% coniferyl alcohol and coniferaldehyde end-groups. The13C-NMR analysis of unirradiated and irradiated tissue revealed a decrease in the relative amount of coniferaldehyde and/or coniferyl alcohol end-groups during irradiation. Prolonged irradiation also introduced new signals centered at 37, 70, and 102 ppm. The results indicate that the present technique, with the formation of DHP in a naturally lignifying carbohydrate environment, has the potential of being a valuable tool for the study of structural changes of lignin during light-induced yellowing.
Reactions of the β-Aryl Ether Lignin Model 1-(4-Hydroxy-3-Methoxyphenyl)-2-(2-Methoxyphenoxy)-1-Propanol on Heating in Aqueous Solution
Authors: Li S. , Lundquist K.
Published: October 2004

The reactions of the β-aryl ether lignin model 1-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1-propanol on heating in aqueous solution have been studied. Guaiacol, isoeugenol, vanillin, 1-(4-hydroxy-3-methoxyphenyl)-1-ethanol, 1,2-bis(4-hydroxy-3-methoxyphenyl)-1-propanol, 2-(4-hydroxy-3-methoxyphenyl)-7-methoxy-3-methyl-2,3-dihydrobenzo[b]furan, dehydrodiisoeugenol and trans-1,2-dihydrodehydroguaiaretic acid were detected in the reaction mixtures. The formation of the products can
be envisioned to proceed via homolysis of an intermediate quinone methide. When 2,6-dimethoxyphenol
was present in the reaction mixtures large amounts of 1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(4-hydroxy-3-methoxyphenyl)-1-propanol were formed and the yields of guaiacol and isoeugenol were
comparatively high. The reaction product pattern can be explained by the occurrence of radical-exchange
reactions. The presence of wood meal in the reaction mixtures resulted in an increase in the yield of
isoeugenol and a lowering of the yield of dehydrodiisoeugenol. The changes in yields in this case can
also be explained by radical-exchange reactions. The significance of homolytic cleavage of β-aryl ether
linkages in connection with the technical processing of wood is discussed.
Structural Analysis of Residual and Technical Lignins by 1H-13C Correlation 2D NMR-Spectroscopy
Authors: Capanema Ewellyn A. , Balakshin Mikhail Yu , Chen Chen-Loung , Gratzl Josef S. , Gracz Hanna
Published: October 2004

Structural analysis was conducted on residual lignin from pine Kraft AQ pulp, Eucalyptus Kraft lignin
from Eucalyptus globulus and Repap Organosolv lignin by 2D 13C-1H correlation NMR spectroscopic
techniques such as HMQC sequence. These lignins contain a rather wide variety of saturated aliphatic
groups. The HMQC NMR spectra of the lignins do not verify the presence of diarylmethane moieties in
any lignin investigated. The type and amount of other condensed structures depend on the nature of lignin
preparation. All the lignins investigated still contained β-O-4′, pino- and syringayresinol (β-β′) and
phenylcoumarane (β-5′) structures. Stilbene structures were also identified. Vinyl ether structures were
present only in Eucalyptus Kraft lignin. All the lignins contain α-carbonyl groups conjugated to aromatic
moieties as terminal side chains rather than involving β-O-4′ structures. No coniferyl alcohol and
coniferyl aldehyde type structures are detected in the lignins after pulping. The spectra of kraft lignins
show some new signals, the origin of which is discussed.
Experimental Determination of Stiffness Variation Across Growth Rings in Picea abies
Authors: Jernkvist L.O. , Thuvander F.
Published: October 2004

The radial and tangential deformations in a single growth ring of Norway spruce, which was subjected
to moderate tensile loading in its radial direction, were measured by use of digital speckle photography.
From the measured displacement field, the transverse coefficients of elasticity ER
, ET
, GRT
and νTR were
determined with respect to radial position in the growth ring. As a result of the abrupt change in stiffness
from latewood to earlywood in the growth ring, it was possible to establish all four coefficients solely
from the radial tension test. The elastic modulus ET
was found to be a factor 15 larger in latewood
than in earlywood, whereas the corresponding variation for ER
was merely a factor 3. The measured variations
were in reasonable agreement with predictions from simple two-dimensional honeycomb models
of the growth ring cellular structure.

The average elastic moduli of the growth ring were found to be twice as large as ER
and ET
measured
in conventional tests on macroscale specimens, whereas the reverse was true for the shear modulus. An
explanation to these differences is sought by analysing the loading conditions and deformation behaviour
of macroscale specimens used in transverse stiffness testing of wood.
Determination of the Material Property Variations Across the Growth Ring of Softwood for Use in a Heterogeneous Drying Model Part 1. Capillary Pressure,Tracheid Model and Absolute Permeability
Authors: Perré Patrick , Turner Ian
Published: October 2004

In this work, the extensive knowledge of wood gained at the Ecole Nationale du Génie Rural des Eaux
et Forêts by using a combination of microscopic observation and experimental work is being used to postulate
material property correlations for a macroscopic heterogeneous “Cerne” growth ring model of softwood.
Mathematical tools such as image analysis and homogenisation are used to develop models that
capture the effect of the density variation within the wood sample of important macroscopic physical
parameters. This first part is devoted to mass transfer in wood due to Darcy's law. Capillary pressure correlations
as a function of local density are deduced from image analysis. Thereafter, a tracheid model is
proposed for softwood. Its shape evolves from earlywood to latewood according to anatomical observations.
Liquid and gaseous permeability values are calculated from this model according to Poiseuille's
flow within cells and assuming a linear flow-pressure loss relationship through the pits.
The Influence of Rays on the Transverse Elastic Anisotropy in Green Wood of Deciduous Trees
Authors: Burgert I. , Bernasconi A. , Niklas K.J. , Eckstein D.
Published: October 2004

The green wood of twelve deciduous tree species was investigated regarding its radial and tangential
moduli of elasticity measured in tension (ER and ET, respectively). In addition, the wood density and the
volume fraction of rays were determined. A strong positive correlation was found between structural and
stiffness properties. A simple two component model was derived for the relationship between the transverse
elastic anisotropy factor (i.e., ER/ET) of the green wood and the relative volume fraction of the axial
and ray tissues. In the radial direction of the wood, the modulus of elasticity is influenced by the wood
density and the volume fraction of rays; in tangential direction only the density seems to be important.
However, the comparison between the elastic anisotropy and the volume fraction of rays indicates that
the rays may have an indirect influence due to their shape.
The Effect of Varying Latewood Proportion on the Radial Distribution of Lignin Content in a Pine Stem
Authors: Gindl W.
Published: October 2004

The radial distribution of lignin content in a pine stem was compared to latewood proportion. With the
exception of the innermost juvenile growth rings, a strong negative correlation was found. However, the
cell-wall lignin content of low lignin growth rings was equal to that of high-lignin growth rings. Therefore,
the difference in lignin content between individual growth rings was solely due to varying ratios of
high-lignin compound middle lamella to low-lignin secondary wall in thin- and thick-walled tracheids.
Effects of Environmental Factors on the Color of Sugi (Cryptomeria japonica D. Don) Yellowish Heartwood
Authors: Chang Shang-Tzen , Cheng Sen-Sung
Published: October 2004

The heartwood of sugi (Cryptomeria japonica D. Don), one of the most important planted trees in Taiwan,
has a pleasant yellow, yellowish red to red color. Unfortunately, its attractive appearance is susceptible
to discoloration after environmental exposure. This degradation is a significant defect that
decreases the value of sugi products. The objective of the present study was to evaluate the effects of
environmental factors on the color of sugi yellowish heartwood. We found that the color eventually
turned to brownish black in the presence of moisture. Under the combined influence of light and oxygen
the color of heartwood changed from yellow to reddish blue. The effect of light wavelengths on the
discoloration of sugi yellowish heartwood was also investigated. After irradiation with light of wavelengths
above 600 nm, the color of sugi yellowish heartwood changed significantly from yellowish to
red. Our findings show that red color enhancement, and hence the economic value of sugi yellowish
heartwood, can be achieved by irradiating with light of wavelengths above 600 nm.
Influence of Tannin-Copper Complexes as Preservatives for Wood on Mechanism of Decomposition by Brown-Rot Fungus Fomitopsis palustris
Authors: Yamaguchi Haruhiko , Yoshino Kyoko
Published: October 2004

The mechanism of preservation by chemically modified tannin and tannin-ammonia-copper agents was examined. Wood decay byF. palustriswas markedly suppressed by processing wood with agents made by mixing chemically modified tannins with ammonia and cupric chloride. When wood powder was treated with these agents, mycelial growth and generated protein increased to some extent. The preservative effects of the chemically modified tannins (RMT and CMT) or compound agents composed of the tannins and ammonia-copper were considered to be due to inhibition of the activities of xylanase, mannase and Cx-cellulase. In the culture medium in which treated wood powder was brought in with these agents, drop of pH by oxalic acid, whichF. palustrisproduces, is not generated. The potency of the effect was thought to be due to chelation of copper, an essential trace element for wood decay byF. palustris, by the tannin, and/or neutralization or suppression of oxalic acid production by ammonia-copper.
Characteristics of Sludges Produced by Destabilization of CCA Preservative Solutions
Authors: Stevanovic-Janezic Tatjana , Cooper Paul A.
Published: October 2004

Chromated copper arsenate (CCA) working solution is partially destabilized over time as a result of
hexavalent chromium (CrVI) reduction by wood extractives and reactive additives such as water repellents
and polyethylene glycol (PEG) wood softening agents. Hot water extracts of several softwood and
hardwood species were used to prepare 2% CCA type C solutions. The softwoods included sapwood and
heartwood of red pine (Pinus resinosa Ait.), jack pine (Pinus banksiana Lamb.), black spruce (Picea
mariana Mill.), balsam fir (Abies balsamea (L.) Mill.) and sapwood of southern yellow pine (Pinus spp.).
Hard wood samples were mixed sapwood and heartwood of red maple (Acer rubrum L.), basswood (Tilia
americana L.), yellow poplar (Liriodendron tulipifera L.) and red oak (Quercus rubra L.). In a similar
way, 2% CCA solutions were prepared containing 4% PEG and 1% paraffin wax formulated water repellent.
The pH and hexavalent chromium content of the CCA solutions were monitored over time until
sludge formation was observed. The obtained sludges were separated and analyzed by Fourier Transform
Infrared Spectroscopy (FT-IR) in the mid-infrared range and by atomic absorption spectroscopy (AAS)
for chromium, copper and arsenic contents. The results of FT-IR and AAS analyses of the sludges indicate
that the products of sludging are of comparable chemical nature regardless of the agent responsible
for the destabilization of CCA solutions. Arsenic and chromium are the major and copper the minor constituent
of the sludges produced by destabilization of CCA solutions examined here.
Extractives and Structural Components in Wood and Bark of Endemic Oak Quercus vulcanica Boiss
Authors: Balaban Mualla , Uçar Günes
Published: October 2004

The bark and wood of an endemic oak species in Turkey,Q. vulcanica, were investigated with regard to main components, phenolics as well as extractives. About 66% of extract free wood consists of polysaccharides, i.e. cellulose and polyoses. Heartwood was found to be rich in ellagitannins, while in bark proanthocyanidins occurred in larger amounts. Extractives soluble in cyclohexane were divided into saponifiables and neutrals. Among saponifiables saturated acids made up the majority, while sterols and nonsteroidal triterpenes were the predominating compounds of the neutral fraction.
Fragmentation of Suberin and Composition of Aliphatic Monomers Released by Methanolysis of Cork from Quercus suber L.,Analysed by GC-MS, SEC and MALDI-MS
Authors: Bento M.F. , Pereira H. , Cunha M.Á. , Moutinho A.M.C. , Berg K.J. van den , Boon J. J. , Brink O. van den , Heeren R.M.A.
Published: October 2004

Suberin from extractive-free cork from Quercus suber L. was depolymerised by methanolysis using different
sodium methanolate (NaOMe) concentrations. 1% and 3% NaOMe completely removed suberin
from cork (54%–56% of extractive-free cork), but for lower concentrations there was incomplete solubilisation;
with 0.05% NaOMe, only approximately 80% of total suberin was removed. The monomeric
composition of the extracts differed significantly: for the 0.05% NaOMe, only alkanoic acids and
diacids were found; the yield of v-hydroxy acids increased with reactant concentration, as well as alkanols
and ferulic acid.

Results from light scattering, SEC and MALDI-MS showed that soluble oligomeric fragments containing
suberinic acids were present in the methanolysis mixture. The molecular weight of these
oligomeric fragments decreased with higher sodium methanolate concentrations.
Controlled Assembly of Glucuronoxylans onto Cellulose Fibres
Authors: Henriksson Åsa , Gatenholm Paul
Published: October 2004

In this study we have shown that cellulose fibres can be coated with regular micron-sized particles by controlling the assembly process of xylans on the cellulose surfaces. When cotton linters were exposed to a 5% water solution of xylan from birchwood at 110°C, 2 h, pH 8, the substrates showed an increase in weight of approximately 6.5%, and visualization by AFM revealed regular particles on the fibre surfaces. The surface modification process was optimized using an experimental design where time, temperature, and pH were varied. The experiments showed that the amount of xylan deposited on the fibres could be varied from 2% up to 20% depending on treatment conditions. The temperature and time were the most important parameters, while pH was not important in the investigated region. The morphology of the deposited xylan layer, as shown by SEM, was dependent on the amount of xylan on the fibre surfaces. At low yield the fibres were coated with a homogenous layer, while at higher yields (20%) regular particles of micron size were identified by AFM analysis. The mechanism of this assembly process of xylan on cellulose fibre surfaces is discussed.
Solid State NMR Studies on Inhomogeneous Structure of Fibre Wall in Kraft Pulp
Authors: Liitiä Tiina , Maunu Sirkka L. , Hortling Bo
Published: October 2004

Solid state NMR spectroscopy was used to analyse the inhomogeneous structure of kraft fibre. Primary
fines, isolated from the original kraft pulp, and secondary fines, isolated after refining, were compared
with the corresponding long fibres. To fractionate fibre wall surface material, the kraft pulp was refined
in stages. After each stage, the secondary fines and long fibres were separated and the long fibres refined
again to peel off the surface material. It was found that the crystallinity of cellulose is lower in fines compared
with the corresponding long fibres. When the fines fractions were compared with each other, the
cellulose crystallinity was observed to increase towards the inner parts of the fibre surface. A very clear
gradient was also seen in the amount of extractives, which was highest in the primary fines rich in ray
cells. The contents of lignin and some hemicelluloses, mainly xylan and glucomannan, were also higher
in fines. Residual lignin isolated from the fines was found to be slightly more condensed than residual
lignin from long fibres.
Characterizing the Surface Roughness of Thermomechanical Pulp Fibers with Atomic Force Microscopy
Authors: Snell Rebecca , Groom Leslie H. , Rials Timothy G.
Published: October 2004

Loblolly pine, separated into mature and juvenile portions, was refined at various pressures (4, 8 and 12
bar). Fiber surfaces were investigated using a Scanning Electron Microscope (SEM) and an Atomic Force
Microscope (AFM). Refiner pressure had a significant effect on the fiber surfaces. SEM images showed
an apparent increase in surface roughness with increased refiner pressure. This was shown quantitatively
with data from the AFM that was analyzed using 5, 2.5 and 1.25 μm scan sizes. A scan size of 2.5 μm
was found to be the most informative in terms of quantifying the effect of the different treatments on the
two fiber types. The calculated surface roughness was greatest at 8 bar for both wood types. Juvenile
fibers in general had higher surface roughness values than mature fibers. The results suggest that refining
pressure may influence the failure mechanism of juvenile and mature wood differently.
Thermal Decomposition of Cellulose Crystallites in Wood
Authors: Kim Dae-Young , Nishiyama Yoshiharu , Wada Masahisa , Kuga Shigenori , Okano Takeshi
Published: October 2004

Decomposition of cellulose crystallites in wood during pyrolysis was studied by X-ray diffraction using
a tension wood of Populus maximowiczii (cottonwood), which contains highly crystalline cellulose. X-ray
diffraction profiles were recorded at varied temperature up to 360°C. By one-hour isothermal treatments,
the cellulose crystallites did not decompose at 300°C, but completely decomposed at 340°C. The
change in equatorial diffraction profile was studied by temperature scan up to 360°C and by isothermal
treatment at the critical temperature of 320°C. Along with the changes by thermal expansion, the
changes in diffraction diagram revealed a characteristic discrepancy between the diminishment of crystalline
order and the reduction in crystallite size; i.e., the intensity of crystalline reflections diminished
steadily while the crystallite size decreased much more slowly. A model of highly heterogeneous decomposition
is proposed to explain this behavior.
Damage and Fracture Mechanisms during Mode I and III Loading of Wood
Authors: Tschegg E.K. , Frühmann K. , Stanzl-Tschegg S.E.
Published: October 2004

Tests under mode I and mode III loading were performed on side grooved Compact-Tension specimens of larch and beech under steady state crack propagation to study the damage and fracture behaviour and the influence of two fibre orientations. From the complete load-displacement diagram, all important damage and fracture mechanical values (stiffness/compliance, microstructural damage, crack initiation energy, specific fracture energy, etc.) have been determined. Crack initiation energy and specific fracture energy are approximately ten times higher for mode III loading than for mode I loading in both wood species. Crack initiation occurs in mode III under external mode III loading, crack propagation, however, takes place under mode I, owing to crack surface interference. The influence of fibre orientation on the (fracture) mechanical properties of beech and larch is different. This difference may be explained mainly by the high number of rays in beech.