bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural studies of lipoproteins and their apolipoprotein components
Authors: Ryan Robert O.
Published: December 2009

Lipid transport processes via the circulatory system of animals are a vital function that utilizes highly specialized lipoprotein complexes. These complexes of protein and lipid impart solubility to otherwise insoluble lipids. The apoprotein components of lipoprotein complexes serve to stabilize the lipid components and modulate particle metabolism and function as ligands for receptor-mediated endocytosis of lipoproteins. We have used an insect (Manduca sexta) model system for studies of lipid transport. In this system, flight activity elicits a dramatic increase in the demand for glycerolipid fuel molecules by flight muscle tissue. These lipids are mobilized from a storage organ and transported through the hemolymph (blood) to the flight muscle by the lipoprotein, lipophorin. This system possesses the unique property that lipids are loaded onto pre-existing high density lipophorin through the action of a lipid transfer particle (LTP). LTP is a high molecular weight hemolymph component that facilitates net vectorial lipid transfer from fat body tissue to lipophorin. The increase in lipid content of the lipoprotein induces association of a low molecular weight amphipathic exchangeable apolipoprotein, apolipophorin III (apoLp-III). ApoLp-III is a 18 kDa protein that normally exists as a water-soluble monomeric hemolymph protein. The structural properties of apoLp-III have been investigated by X-ray crystallography. ApoLp-III from Locusta migratoria adopts a five helix bundle conformation wherein each of the amphipathic helices orients with its hydrophobic face directed toward the interior of the bundle. It has been hypothesized that lipid association requires a dramatic conformational change wherein the helix bundle opens about putative hinge domains located in the loops between helices. The data accumulated support the concept that apoLp-III is a member of the broad class of exchangeable apolipoproteins and structural information learned from this system is directly applicable to analogous proteins in higher organisms.Key words: lipid transport, apoprotein, lipoprotein, Manduca sexta, diacylglycerol.
Purification of P26h: a hamster sperm protein
Authors: Coutu Louise , Rosiers Pascal Des , Sullivan Robert
Published: December 2009

P26h is a 26 kDa glycoprotein, located on the acrosome cap of hamster spermatozoa, involved in the species specificity of gamete interaction. We have purified this protein from hamster spermatozoa collected from the distal cauda region of the epididymis. Its purification was realized following a three-step procedure: detergent extraction, ion-exchange chromatography, and chromatofocusing. Protein partitioning using Triton X-114 (the first step) showed a ratio of 5:1 between the resulting aqueous and detergent phase. P26h was found almost exclusively in the aqueous phase where it represented about 10–12% of the total protein content. When the desalted aqueous phase was loaded on a carboxymethyl column for cation-exchange chromatography, about 80% of the proteins did not bind to the matrix and were eliminated. P26h was eluted from the column with a linear gradient of salt. At this point, P26h had a rate of purification estimated at 45–55%; three other major proteins of <21, 45, and 63 kDa remained in the sample. These undesired proteins were eliminated by submitting these samples to chromatofocusing using a PBE 94 polybuffer exchanger column. Indeed, P26h was collected almost in the dead volume of the column while the other proteins were eluted much later. Two-dimensional gel electrophoresis and Western blotting were performed to determine the purity of P26h. Only one major spot was detected, confirming the purity of P26h. Usefulness of this purified sperm antigen in the understanding of the physiology of mammalian fertilization is discussed.Key words: sperm protein, epididymis, purification.
Isolation and partial characterization of a high molecular weight anionic glycoconjugate from transforming growth factor-β treated bovine articular chondrocyte cultures
Authors: Chan Catherine K. T. , Anastassiades Tassos P.
Published: December 2009

A high molecular weight anionic glycoconjugate was isolated from the media of the transforming growth factor-β treated chondrocyte cultures by anion-exchange chromatography on DEAE–Sephacel and Mono Q columns and was partially characterized. This high molecular weight anionic glycoconjugate was not detected in the non-treated (control) cultures. Characterization studies showed that the glycoconjugate is a non-reducible, non-collagenous glycoprotein containing O-linked, N-linked, and sialic acid substituted carbohydrate units. The isolated glycoconjugate stained "blue" with Stains All and migrated as a single band on sodium dodecyl sulfate gradient gels (2.5–10% acrylamide – diallyl tartardiamide) at an estimated molecular weight of 540 000. Amino acid and amino sugar analyses showed that it is rich in aspartic acid – asparagine, glutamic acid – glutamine, alanine, proline, and glycine, and contains galactosamine and glucoasmine. This transforming growth factor-β inducible glycoprotein may be involved in cell differentiation and in the cartilage repair process. It may also be used as a marker to localize the biological activity of transforming growth factor-β in articular cartilage.Key words: transforming growth factor-β, chondrocytes, anionic glycoconjugate synthesis.
Equilibrium enzymes in metabolic pathways
Authors: Brooks S. P. J.
Published: December 2009

It is commonly believed that certain reactions in a metabolic sequence may be at or close to equilibrium because of the large excess of catalytic capacity compared to the flux through these enzyme loci. Simple algebraic manipulations can show that the equilibrium and steady state conditions are mutually exclusive. However, solution of the complete reaction schemes for model "equilibrium" reactions shows that they can remain far from equilibrium even though the ratio of enzyme flux to steady state flux through the overall pathway is high. These calculations show that a reaction's proximity to equilibrium depends on the overall flux through the enzyme locus as well as on the kinetic parameters of the other enzymes in the pathway. Thus, combinations of kinetic parameters may exist that allow certain reactions to approach equilibrium but these conditions are not universal.Key words: equilibria, theoretical kinetics, metabolic control.
Palmitoylation: a post-translational modification that regulates signalling from G-protein coupled receptors
Authors: Morello Jean-Pierre , Bouvier Michel
Published: December 2009

Protein acylation is a post-translational modification that has seized much attention in the last few years. Depending on the nature of the fatty acid added, protein acylation can take the form of palmitoylation, myristoylation, or prenylation. Palmitoylation has been implicated in the modification of several different proteins and is particularly prevalent in G-protein coupled receptors and their cognate G-proteins, where it is thought to have an important regulatory function. Given that palmitoylation of these proteins is a dynamic phenomenon in which turnover rate is modulated by agonist activation, it is thought to be implicated in processes such as receptor phosphorylation and desensitization as well as in G-protein membrane translocation. A better understanding of the regulation of signal transduction mediated by G-protein coupled receptors will require the identification and characterization of those enzymes implicated in the palmitoylation and depalmitoylation process of this large class of receptors and their signalling allies.Key words: palmitoylation, β-adrenergic receptor, G-protein, phosphorylation, desensitization.
Role of p70 S6 kinase in cytokine-regulated hemopoietic cell survival
Authors: Scheid Michael P. , Charlton Lorin , Duronio Vincent , Pelech Steven L.
Published: December 2009

The signalling mechanisms required for cell survival remain relatively undefined. We and others have shown that phosphatidylinositol 3-kinase (PI 3-kinase) is an important enzyme in the prevention of apoptosis, and this property is independent of p21ras– MAP kinase activation. It is therefore important to define the downstream targets of this enzyme mediating the inhibition of apoptosis. We report here that p70 S6 kinase, a protein critical for progression through the cell cycle and a downstream effector of PI 3-kinase, is not required for the survival of cytokine-stimulated human T-cells or murine mast cells. The potent inhibitor of p70 S6 kinase activation, rapamycin, was unable to induce apoptosis in cells stimulated with cytokines. As well, PI 3-kinase inhibitors that also blocked the activation of p70 S6 kinase were able to induce apoptosis. These studies, therefore, describe a bifurcation of signalling pathways from PI 3-kinase leading to different physiological outcomes.Key words: p70 S6 kinase, phosphatidylinositol 3-kinase, apoptosis, cytokines, wortmannin.
Spermidine-condensed DNA and cone-shaped lipids improve delivery and expression of exogenous DNA transfer by liposomes
Authors: Ibáñez Miguel , Santiago Rosalba , Wong Carlos , Baeza Isabel , Gariglio Patricio , Chávez Pedro
Published: December 2009

A new liposome system containing spermidine-condensed DNA and negative cone-forming lipids designed to improve gene delivery and expression is described. The compacted nature of condensed DNA forms permitted a higher extent of encapsulation of DNA in liposomes. These vesicles contained fusogenic cone-shaped lipids to increase fusion between liposomes and membranes to enhance the amount of DNA delivery into the cells. In addition, the insensitivity of condensed DNA forms to endonucleases and restriction enzymes, as well as their higher activity in both replication and transcription, improve foreign DNA expression. These improvements in condensed DNA encapsulation in liposomes, transfer into the cells, and DNA expression increase the number of transfected cells and produce a higher level of gene expression in most transfected cells. This is reflected in the 60-fold cell culture transfection increase compared with traditional liposome transfection systems. This liposome system does not cause any apparent damage to the transfected cells; furthermore, the liposomes are small, 400–500 nm, and have negative surface charges that can prolonge their circulation half-lives in vivo, permitting their use for in vivo gene therapy applications.Key words: gene transfer, liposome, spermidine-condensed DNA, cone-shaped lipids.
Production of type IV collagen and 72-kDa gelatinase by human endothelial cells cultured in high glucose. Effects of a protein kinase C inhibitor, GF 109203X
Authors: Grigorova-Borsos Anne-Marie , Bakillah Ahmed , Urios Paul , Leblond Valérie , Guillot Raymonde , Sternberg Michel
Published: December 2009

Since diabetic microangiopathy and macroangiopathy are characterized by type IV collagen accumulation in vascular basement membranes, it was of interest to study type IV collagen production and type IV collagenase secretion by endothelial cells (EC) cultured in high glucose and to evaluate the role of protein kinase C (PKC) activation in the alterations induced by high glucose. Primary cultures of human umbilical vein EC were exposed to high glucose concentration for 3 days at the beginning of confluence. The number of EC decreased with glucose concentration from 5 to 50 mM. At 16.7 mM glucose concentration, the amount of type IV collagen, determined by a two-step ELISA, increased in the culture supernatant and in the insoluble fraction associated with the extracellular matrix and cells; proline incorporation was more markedly elevated in the collagenous than in the total proteins of the culture supernatant and of the extracellular matrix and cell extracts. Gelatin zymography of the culture supernatant showed that EC mainly produce a 72-kDa gelatinase known to degrade type IV collagen. At 16.7 mM glucose concentration, total gelatinase activity per millilitre of culture supernatant was reduced and the 72-kDa gelatinase activity measured on the zymogram scan was lowered. When EC were exposed to 16.7 mM glucose, the specific PKC inhibitor GF 109203X corrected the increases in type IV collagen concentration and in proline incorporation into the collagenous or total proteins present in the culture supernatant or in the extract of the insoluble fraction, including the extracellular matrix and cells. Our results show that soluble and insoluble type IV collagen accumulation by EC cultured at high glucose concentration is not only associated with increased synthesis of the collagenous and total proteins but also with decreased total 72-kDa gelatinase activity in the extracellular fluid. The observed effects of GF 109203X are in favour of the involvement of PKC activation in the type IV collagen accumulation.Key words: human umbilical vein endothelial cells, high glucose, type IV collagen, type IV collagenase, protein kinase C inhibitor
Novel self-association fibronectin sites
Authors: Carnemolla Barbara , Leprini Alessandra , Querzé Germano , Urbini Stefania , Zardi Luciano
Published: December 2009

In this study, we report a strong interaction between two contiguous proteolytic fragments of fibronectin, each having a mass of about 16 kDa. This interaction was stable in 4 M NaCl and 4 M urea and dissociation of the two fragments required buffers containing 0.5% sodium dodecyl sulphate. After purification, these peptides maintained their ability to interact when mixed. One fragment was made up of type III repeat 4 and part of 5, the other by repeat 6 and part of 5. Such strong interaction between two fibronectin regions may play a role in fibronectin conformation as well as during fibronectin fibril formation.Key words: fibronectin, type III repeats interaction.
The importance of the microenvironment in breast cancer progression: recapitulation of mammary tumorigenesis using a unique human mammary epithelial cell model and a three-dimensional culture assay
Authors: Weaver V. M. , Bissell M. J. , Fischer A. H. , Peterson O. W.
Published: December 2009

The extracellular matrix (ECM) is a dominant regulator of tissue development and homeostasis. "Designer microenvironments" in culture and in vivo model systems have shown that the ECM regulates growth, differentiation, and apoptosis in murine and human mammary epithelial cells (MEC) through a hierarchy of transcriptional events involving the intricate interplay between soluble and physical signaling pathways. Furthermore, these studies have shown that these pathways direct and in turn are influenced by the tissue structure. Tissue structure is directed by the cooperative interactions of the cell–cell and cell–ECM pathways and can be modified by stromal factors. Not surprisingly then, loss of tissue structure and alterations in ECM components are associated with the appearance and dissemination of breast tumors, and malignancy is associated with perturbations in cell adhesion, changes in adhesion molecules, and a stromal reaction. Several lines of evidence now support the contention that the pathogenesis of breast cancer is determined (at least in part) by the dynamic interplay between the ductal epithelial cells, the microenvironment, and the tissue structure (acini). Thus, to understand the mechanisms involved in carcinogenesis, the role of the microenvironment (ECM as well as the stromal cells) with respect to tissue structure should be considered and studied. Towards this goal, we have established a unique human MEC model of tumorigenesis, which in concert with a three-dimensional assay, recapitulates many of the genetic and morphological changes observed in breast cancer in vivo. We are currently using this system to understand the role of the microenvironment and tissue structure in breast cancer progression.Key words: extracellular matrix, integrin, adhesion molecules, breast cancer, microenvironment.
Different human tenascin-C variants in the extracellular matrix of cultured human fibroblasts
Authors: Siri Annalisa , Allemanni Giorgio , Gaggero Barbara , Zardi Luciano
Published: December 2009

Using an immunoadsorbent prepared with a mononoclonal antibody specific for the high molecular mass isoform of human tenascin-C, we purified tenascin-C molecules containing at least one large subunit from the extracellular matrix of cultured normal human fibroblasts. Sodium dodecyl sulphate – polyacrylamide gel electrophoresis and immunoblotting analyses have shown that both high and low molecular mass subunits are present in these tenascin-C preparations. Because the monoclonal antibody used is able to bind only the high molecular mass isoform, the present data show that part of the tenascin-C present in the fibroblast extracellular matrix is made up of heterohexameric molecules.Key words: extracellular matrix, tenascin-C isoforms, hexamers.
Variants of integrin β4 subunit in human endometrial adenocarcinoma cells: mediators of ECM-induced differentiation?
Authors: Strunck Elisabeth , Vollmer Gunter
Published: December 2009

The influence of extracellular matrix (ECM) on expression and function of integrins in carcinogenesis and differentiation is not well understood, but the importance of altered adhesion features for tumor development and progression is obvious. Integrins as versatile molecules are mainly responsible for mediating cell–matrix interactions and transmembrane signal transduction. They are capable of transducing outside-in signals from ECM components or conversely to organize the matrix by inside-out signaling. In the study presented here, we report that the reconstituted basement membrane, Matrigel™, which induces morphological and functional differentiation of the endometrial adenocarcinoma cell line HEC 1B(L), also regulates the expression of various forms of the integrin β4 subunit. Furthermore, we were able to identify full-length isoforms with and without an altered cytoplasmic domain as well as truncated forms. Our findings suggest a regulatory role of integrin β4 isoforms and fragments in the process of in vitro differentiation of HEC 1B(L).Key words: endometrium, tumor cells, differentiation, extracellular matrix, β4-integrin expression.
Localization of urokinase to focal adhesions by human fibrosarcoma cells synthesizing recombinant vitronectin
Authors: Wilcox Sarah A. , Reho Thomas , Tominna-Sebald Eiman , Mckeown-Longo Paula J. , Higgins Paul J.
Published: December 2009

Cell surface plasminogen activators have been proposed to participate in cell migration and invasion by activating both intracellular signaling pathways and extracellular proteolysis. Urokinase-type plasminogen activator (uPA) is secreted from many cell types and localizes to focal contact areas when cells are seeded onto the plasma protein vitronectin. Induction of vitronectin synthesis during migration of neural crest cells and growth of certain tumors suggests that the de novo synthesis and deposition of vitronectin into the tissue matrix may remodel the matrix to provide an environment suitable for cell migration and (or) tumor invasion. To investigate the effects of vitronectin secretion and matrix deposition on the localization and activity of cell-associated uPA, HT-1080 fibrosarcoma cells were transfected with the Rc/CMV expression vector containing a vitronectin cDNA insert and stable cell lines expressing vitronectin were selected. Vitronectin-secreting cells were allowed to attach and spread on collagen- and fibronectin-coated substrates. Within 6 h, vitronectin was detected on the substrate; vitronectin synthesis was accompanied by the clustering of both the αvβ5vitronectin receptor and uPA into vinculin-containing focal adhesions. Although mock transfected cells formed small focal adhesions on both collagen and fibronectin, no co-localization of uPA or αvβ5to focal adhesions was evident in these cells. Vitronectin-secreting cells also exhibited decreased levels of plasminogen activation and increased levels of cell adhesion as compared with the mock transfected cells. These data demonstrate that the synthesis of vitronectin and its matrix association by transfected HT-1080 fibrosarcoma cells results in localization of uPA to oαvβ5containing focal adhesions, decreased cell surface uPA activity, and an increase in cell adhesion.Key words: urokinase, vitronectin, focal adhesions, αvβ5integrin.
Analysis of interactions between the subunits of protein kinase CK2
Authors: Litchfield David W. , Slominski Elzbieta , Lewenza Shawn , Narvey Michael , Bosc Denis G. , Gietz R. Daniel
Published: December 2009

Protein kinase CK2, which was formerly known as casein kinase II, is a highly conserved protein serine/threonine kinase implicated in the control of cell proliferation through its phosphorylation of regulatory nuclear proteins. The enzyme consists of catalytic (α and (or) α′) subunits and β subunits that modulate the activity of the catalytic subunits. These subunits are arranged in homotetrameric (i.e., α2β2or α′2β2) or heterotetrameric (i.e., αα′β2) complexes. We previously demonstrated using the yeast two-hybrid system that α (or α′) subunits can interact with β subunits but not other α (or α′) subunits. By comparison, β subunits can interact with α (or α′) and with β subunits, suggesting that the protein kinase CK2 holoenzyme forms because of the ability of p subunits to dimerize, bringing two heterodimers (αβ or α′β) into a tetrameric complex. In the present study, we used the yeast two-hybrid system to examine the domains of interactions between the α and β subunits of protein kinase CK2. These studies indicate that the ability of β to interact with α resides within the carboxy-terminal domain of β. By comparison, our studies suggest that individual domains of α are not sufficient for interactions with β.Key words: protein kinase CK2, casein kinase II, yeast two-hybrid system, subunit interaction, signal transduction.
Adsorption of dissolved nitrogen by forest mineral soils
Authors: Kothawala D.N. , Moore T.R.
Published: December 2009

Dissolved nitrogen (N) species, including ammonium (NH4+-N), nitrate (NO3–-N), and dissolved organic nitrogen (DON), are important nutrient sources in soils. The mobility of DON and NH4+-N in soil solutions is influenced by abiotic adsorption to mineral soil particle surfaces. We determined relationships between soil properties and their ability to adsorb NH4+-N, NO3–-N, and DON, using batch experiments. A range of 41 mineral horizons was collected from across Canada, including Podzols, Brunisols, Luvisols, Gleysols, and an organic soil. The adsorption of DON and dissolved organic carbon (DOC) were positively correlated (R2= 0.86), and both were best explained by the amount of iron and aluminum associated with poorly crystalline phases. Adsorption of NH4+-N was strongest in Gleysols and Luvisols, while adsorption of NO3–-N was weak in all soils. A reduction in the DOC:DON ratio was observed for most mineral horizons (89%) after equilibration from an original ratio of 35:1. Mineral horizons with a net desorption of DON had a significantly greater reduction in the final DOC:DON ratios than horizons with a net adsorption of DON. The results from this study found that while similar soil properties could predict DOC and DON adsorption, DON was slightly more mobile than DOC.
Discerning responses of down wood and understory vegetation abundance to riparian buffer width and thinning treatments: an equivalence–inequivalence approach
Authors: Anderson Paul D. , Meleason Mark A.
Published: December 2009

The combined effectiveness of thinning and riparian buffers for increasing structural complexity while maintaining riparian function in second-growth forests is not well documented. We surveyed down wood and vegetation cover along transects from stream center, through buffers ranging from <5 to 150 m width into thinned stands, patch openings, or unthinned stands of 40- to 65-year-old Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) forests in western Oregon, USA. Small-wood cover became more homogeneous among stream reaches within 5 years following thinning, primarily due to decreases for reaches having the greatest pretreatment abundance. Mean shrub cover converged, predominantly because of decreases in patch openings. Herbaceous cover increased, particularly in patch openings. Relative to unthinned stands, herbaceous cover was similar in wide buffers and increased in the narrowest buffers and in narrow buffers adjacent to patch openings. Moss cover tended to increase in thinned areas and decrease in patch openings. Both conventional point-null hypothesis tests and inequivalence tests suggested that wood and vegetation responses within buffers of ≥15 m width were insensitive to the treatments. However, inherently conservative equivalence tests infrequently inferred similarity between thinned stands or buffers and untreated stands. Difficulties defining ecologically important effect size can limit the inferential utility of equivalence–inequivalance testing.
Character-marked furniture made from red alder harvested in southeast Alaska: product perspectives from consumers and retailers
Authors: Bumgardner Matthew , Nicholls David , Barber Valerie
Published: December 2009

In recent decades, red alder ( Alnus rubra Bong.) has become an important Pacific Northwest hardwood in appearance-grade lumber markets, such as exports, furniture, and cabinets. However, red alder generally is a short-lived pioneer species, and small logs can result in proportionally large volumes of lower grade lumber containing numerous visual defects, such as knots, often referred to as character marks. Given that markets for character-marked wood could provide an income stream for management of red alder, it becomes important to understand consumer and retailer response to character-marked red alder products. In the current study, we used a policy capturing approach (the lens model) to assess the cues used by furniture consumers and retailers to evaluate several furniture pieces constructed from character-marked red alder lumber. The cues used by consumers and retailers to form willingness-to-pay judgments were found to be different. Character marks, design, and naturalness were important to consumers. None of the investigated cues were significant to retailers, suggesting they were using an entirely different model. Such divergence creates challenges in the forestry supply chain for development of new forest products.
Individual-tree growth dynamics of mature Abies alba during repeated irregular group shelterwood (Femelschlag) cuttings
Authors: Puettmann Klaus J. , D’Amato Anthony W. , Kohnle Ulrich , Bauhus Jürgen
Published: December 2009

This study investigated the individual-tree diameter response of mature silver fir ( Abies alba Mill.) to reproduction harvests (Femelschlag: an irregular group shelterwood method) on six sites in the Black Forest, Germany. On each site, four different treatments were applied, including a control treatment and short-, medium, and long-term regeneration periods aimed at the complete removal of overstory trees within 20, 35, and 50 years, respectively. These treatments created a wide variety of growing conditions for individual trees. Relationships between relative diameter growth and stand-level and neighborhood interaction indices were evaluated. Growing conditions for individual trees in control conditions were best characterized using Lorimer’s index for a 16 m radius neighborhood. Equations predicting tree growth in control stands underpredicted initial growth of trees after harvesting operations, suggesting a release effect that is not captured by postharvest density. This effect was larger for smaller trees and influenced by removal intensity. Growth response to density reductions was also influenced by previous harvests. Our results suggest that the growth response of mature trees to reproduction harvests may become an important consideration when increased emphasis is placed on managing for long-term regeneration periods.
The outbreak history of Dothistroma needle blight: an emerging forest disease in northwestern British Columbia, Canada
Authors: Welsh Cedar , Lewis Kathy , Woods Alex
Published: December 2009

Native pathogens are normally limited in the damage they cause by host resistance and (or) environmental conditions that limit one or more phases of the disease cycle. Changes to host or environmental conditions can relax these limits and result in disease emergence. Until recently, Dothistroma needle blight (Dothistroma), caused by Dothistroma septosporum (Dorog.) Morelet, has had only minor impacts on native forest trees in western North America. Over the past decade in the forests of northwestern British Columbia, Canada, Dothistroma has caused extensive mortality in managed plantations of lodgepole pine ( Pinus contorta Dougl. ex Loud. var. latifolia Engelm.), and even mature pine trees are succumbing. We used dendrochronological techniques to reconstruct the temporal patterns of past Dothistroma outbreaks in the area using tree-ring series from sites with documented outbreaks. We found that Dothistroma outbreaks in northwest British Columbia have occurred periodically over the last 174 years, with an increase in outbreak incidence and extent since the 1940s. The most distinct change observed in the outbreak history has been the greater severity and synchrony among the sites affected during the current outbreak. A recently observed climate change trend over the study area may represent an environmental trigger that synchronized the current outbreak causing the widespread emergence of the disease.
The sensitivity of nitrogen fixation by a feathermoss–cyanobacteria association to litter and moisture variability in young and old boreal forests
Authors: Gundale Michael J. , Gustafsson Helena , Nilsson Marie-Charlotte
Published: December 2009

We conducted a pair of experiments to assess whether nitrogen (N) fixation by a feathermoss–cyanobacteria association was sensitive to moisture availability and quality of litter inputs, and whether sensitivity to these factors differed between young and old forests. In our first greenhouse experiment, we experimentally varied the frequency of water addition to Pleurozium schreberi (Brid.) Mitt. collected from young and old forest sites. This experiment revealed that the extreme drought treatment reduced N fixation capacity (measured via acetylene reduction), whereas daily watering increased N fixation capacity. The experiment also demonstrated that sensitivity to moisture variability was greater in old forests than in young forests. In a second greenhouse experiment, we repeatedly applied litter extracts from six common boreal species, Pinus sylvestris L., Picea abies (L.) Karst., Betula pubescens Ehrh., Vaccinium myrtillus L., Vaccinium vitis-idaea L., and Empetrum hermaphroditum Lange ex Hagerup. After 43 days, we found no significant effects of litter or litter by stand age interaction on N fixation capacity of P. schreberi, whereas stand age remained a significant factor. These experiments suggest that the N fixation capacity of the P. schreberi – cyanobacteria association is relatively resistant to short-term variation of litter as an environmental driver but that precipitation extremes in old forests may significantly alter the N fixation capacity of the association.
Dendrochronology of Quercus ilex L. and its potential use for climate reconstruction in the Mediterranean region
Authors: Campelo F. , Nabais C. , García-González I. , Cherubini P. , Gutiérrez E. , Freitas H.
Published: December 2009

Holm oak ( Quercus ilex L.) is a long-lived species widely distributed across the Mediterranean Basin, with potential value for dendrochronology and dendroclimatology. However, tree-ring dating in Q. ilex is a complex task that has limited the number of dendrochronological studies using this evergreen species. In the present work, it was investigated if old Q. ilex trees showed annual tree rings and whether they can be used as climate proxies. A long tree-ring chronology (126 years) of Q. ilex was developed using cross sections of 20 trees from the Guadiana river basin (Portugal). The high correlation among tree-ring series suggested that tree growth was controlled mainly by climate. Response function analysis showed a positive correlation between tree-ring width and precipitation from October(t–1)of the previous year to January(t)of the current year and in May(t). Tree-ring width was negatively correlated with the North Atlantic oscillation that exerts a strong influence on the precipitation over Iberia. Negative pointer years were triggered by dry years and became more frequent during the last decade of the 20th century. In conclusion, it is possible to accurately date old Q. ilex trees, and their tree rings could be used for climate reconstructions across the Mediterranean.
Genetic resistance of spruce to gall-forming adelgids (Hemiptera: Adelgidae)
Authors: Bains B. , Isik F. , Strong W.B. , Jaquish B. , McLean J.A. , El-Kassaby Y.A.
Published: December 2009

Adelgids (Hemiptera: Adelgidae) gall vegetative and reproductive shoots of interior spruce (Picea spp.), causing growth impairment, seed loss, and aesthetic decline. We tested the theory that susceptibility to galling is under genetic control in spruce. We assessed natural galling incidence in a spruce progeny test located in southern British Columbia. The experiment was composed of a replicated 13-parent incomplete, partial diallel with 42 full-sib families. Moderate evidence of genetic control of susceptibility–resistance was observed with individual narrow-sense heritability of 0.17. We observed considerable genetic variation among parents for resistance to gall formation as shown by high heritability (0.87) of family means. Breeding values for parental susceptibility to adelgid attack ranged between 0.25 and 0.76, indicating that selection for reduced susceptibility would be successful. The benefits of screening for resistance to adelgid attack are discussed in relation to adelgid pest management, insect’s life-cycle, and tree health.
FLOER HOMOLOGY FOR SYMPLECTOMORPHISM
Authors: HER HAI-LONG
Published: December 2009

Let (M,ω) be a compact symplectic manifold, and ϕ be a symplectic diffeomorphism on M, we define a Floer-type homology FH*(ϕ) which is a generalization of Floer homology for symplectic fixed points defined by Dostoglou and Salamon for monotone symplectic manifolds. These homology groups are modules over a suitable Novikov ring and depend only on ϕ up to a Hamiltonian isotopy.
ON THE BOUNDARY OF TOPOLOGICAL CHAOS FOR THE MILNOR–THURSTON WORLD
Authors: LABARCA RAFAEL , PUMARIÑO ANTONIO , RODRÍGUEZ JOSÉ ANGEL
Published: December 2009

In the present paper we characterize the boundary of topological chaos and the levels of the entropy for the Milnor–Thurston shift map.
ASSESSMENT OF MARITAL COMMUNICATION AND CONFLICT RESOLUTION: PSYCHOMETRIC PROPERTIES OF TWO SCALES
Authors: CHEUNG SIU-KAU
Published: December 2009

Preliminary psychometric data are presented for two Chinese self-report scales that assess marital communication and conflict resolution. These scales were based on English versions of the scales but adapted to fit the local cultural context. Results showed that the 11-item Marital Communication Scale and the 8-item Chinese Ineffective Arguing Scale produced scores that were internally consistent. Their correlations with the Kansas Marital Satisfaction Scale were high and significant. There was moderate evidence to support that the scales distinguished between respondents with and without marital problems.

本文报导关於两个婚姻关系量表的发展过程和检订结果。量表之一名为「婚姻沟通量表」，它的内容主要取材于西方有关的量表。在检订前，研究员已按本地文化修订其项目，亦就其原内容不足之处增添了两条题目。第二个量表名为「无效的争辩方式」量表，它有八条题目，亦是按有关的西方量表经修订后采用的。检订结果显示，婚姻沟通量表在删除一条题目后，有颇高的内在一致性信度，而无效的争辩方式量表中八题的分数亦有很高的内在一致性。两个量表的分数和肯萨斯州婚姻满意程度量表有很高的相关，量表的分数亦有助区分带有婚姻问题者和没带婚姻问题者。这些结果都为量表的信度和效度，提供初步的支持。
CRITICAL ISSUES IN MULTIDISCIPLINARY CHILD SEXUAL ABUSE ALLEGATION INVESTIGATIONS
Authors: CHEUNG MONIT
Published: December 2009

During the past ten years, research in the area of investigative interviews of child sexual abuse has focused on the child victim. Current literature in this area can be grouped into eight interrelated categories: (1) the developmental aspects of memory recall, (2) understanding children's language, (3) avoidance of repeated questioning, (4) validation and children's credibility, (5) false allegations, (6) videotaping interviews, (7) using anatomical dolls, and (8) interviewing techniques. A growing concern is the use of developmentally appropriate techniques to avoid false allegations. A dual-focus approach in conducting an investigative interview and 12 guiding principles are recommended for improving social workers' knowledge, skills and attitude.
华人辅导法: 迈向本土化的途径
Authors: 李 怀敏
Published: December 2009

本文提出一个新的问题：在现代中国人的心灵里，中国古代心理思想是否已成为被博物馆化了的文化古董，连满足情绪需要和治疗心灵创伤的实用价值都没有了，以致我们无法在此基础上，建构出一套适合华人的心理辅导法？在中国古代心理思想中，其实一直存有一套庞大心理辅导体系和颇为缜密的范式。今天需要的是一种足以梳理中国古代心理思想的知识考古方法，并且采用扎根理论 (Grounded Theory) 的研究进路，在结合观察现今华人日常生活的心理运作及行为的基础上，设计出本土的辅导理论和方法，即选择华人所熟悉的心理想法或经验为研究概念，考虑中华文化、社会体系反映在个体心理体系 (包括语言意义系统) 的情况，从中找出华人行为的真正意义，进而寻找适合研究华人及其心理概念的设计及工具，并且在这些设计及工具的基础上，进一步发展足以解释华人心理行为的模式和理论，并据此建立辅导华人的知识体系。

This paper discusses possible ways to develop indigenous counselling theories and techniques that are based on the philosophies and knowledge of Chinese traditional counselling practices. Indigenous theories and techniques should have their own knowledge substance, terminology and language, to describe and understand the Chinese behaviours, which are very different from what are described in the Western counselling theories. To begin with, this paper will give a brief overview of the rationale for developing indigenous counseling theories and techniques. There is a strong psycho-social component in accord with Chinese philosophies about human and nature in the majority of Chinese classical canons. This psycho-social component has a solid scientific ideology and has voluminous empirical evidence. Based upon these materials, this paper suggests that it is possible to develop indigenous counselling approaches that are in accordance with the Chinese world view and cultural practices. All the new indigenous theories, counselling processes and specific interventions should reflect the foundation of Chinese thought. They are the fundamental platform upon which indigenous counselling approaches are built.
香港社会工作本土化的沉思 (一) 本土化的回顾与前瞻
Authors: 叶 锦成
Published: December 2009

社会工作本土化对面对西方文化霸权产生下的社会工作模式的本土应用是必需的反省。但本土化本身就是一个非常复杂的过程，社会工作本质也异常复杂，因此社会本土化基本是一个不易进行的反省。本文作者尝试从有关本地文献中去检视香港社会工作本土化的发展。香港社会工作从 “西方化” 的西方理论的硬套，慢慢地对香港本土的处境有所反省，到九十年代这讨论变得比较热闹。社会工作理念的本土反省和地道知识追寻也揭开序幕。寄望廿一世纪香港社会工作本土化能从理念和处境的反省渐渐展开对本土社会工作理论的追寻。

Social work indigenisation is a necessary reflection under the Western cultural imperialism. However, indigenisation is a highly complicated and multi-dimensional process. The natures of social work are also controversial and diversified. In this paper, the writer tries to discuss the process of indigenisation in social work practice in Hong Kong. It seems that social work practice in Hong Kong gradually removed its attachment on "Westernised model" to reflection of local social and cultural contexts. In the 1990s, the debates on indigenisation began to gain enough momentum for a more comprehensive and holistic reflection of social work practice in Hong Kong.
MANAGERIALISM AND SMALL NGOS IN HONG KONG
Authors: CHANG SIU-WAH
Published: December 2009

Nine Hong Kong small NGO Chief Executive Officers gathered to discuss their perceptions based on their experience during the welfare reform. The paper focuses on tension, opportunities and ways in addressing the issues brought along by the arrival of managerialism in the local welfare scene.

九间香港小型非牟利机构的总干事一起讨论在福利改革中的体验和观感。 本文集中讨论管理主义降临香港社会福利界带来 的压力、 机遇和应变的方法。
CARE OR CONTROL: THE STRUGGLES OF PROBATION OFFICERS IN WORKING WITH YOUNG PROBATIONERS WHO ABUSED PSYCHOTROPIC DRUGS IN HONG KONG
Authors: SIM TIMOTHY
Published: December 2009

Psychotropic drug abuse among young persons below 21 years old has been increasing at an alarming rate in Hong Kong recently. Probation officers when working with young probationers who abuse psychotropic drugs need to contend not only with a complex phenomenon, but be challenged by the dilemmas of the nature of their profession between care and control. This article, by drawing from a discussion with a group of probation officers and feedback from a group of young probationers, raises some issues and questions for probation service in Hong Kong pertaining to working with young probationers who abuse psychotropic drugs. Some suggestions are made for probation officers to achieve more effective planning and interventions in working with young probationers who abuse psychotropic drugs.

由 於 滥 用 精 神 药 物 是 一 个 颇 复 杂 的 现 象， 身 兼 数 职 的 感 化 官 要 有 效 地 帮 助 日 益 增 多 的 滥 用 精 神 药 物 的 青 少 年， 委 实 不 易。 本 文 根 据 一 次 与 香 港 感 化 官 的 讨 论 和 一 群 接 受 感 化 的 青 少 年 的 回 应， 探 讨 感 化 官 处 理 青 少 年 滥 用 精 神 药 物 问 题 时 所 遇 的 挑 战， 并 建 议 符 合 社 会 工 作 价 值 和 香 港 情 况 的 方 案。
范 式 转 移 —— 新 社 会 下 的 社 会 福 利 与 社 会 工 作
Authors: 冯 可 立
Published: December 2009

在 市 场 化、 全 球 化、 程 序 化 的 新 社 会 下， 社 会 福 利 和 社 会 工 作 面 临 范 式 转 移 的 挑 战。 社 会 福 利 的 两 个 意 义：安 然 状 态 与 官 民 关 系， 都 已 经 被 重 新 诠 释。 生 产 力 已 经 成 为 了 主 要 论 述， 严 爱 已 取 代 了 仁 爱。 社 会 工 作 者 以 往 的 专 业 自 主， 与 案 主 的 密 切 关 系， 也 被 解 构 了。 作 为 社 会 渐 进 改 革 派 的 社 会 工 作 专 业， 应 该 怎 样 走 下 去 呢？

Under the New Society of globalisation, marketisation and programisation, there was a paradigm shift in social welfare and social work. The two meanings of social welfare – the state of well-being and the political relationship between the State and its people – were being reconstructed. Productivity began to replace the sense of well-being, and "tough love" also replaced kindness. Professional autonomy and the close relationship of "worker-client" of social work were also deconstructed. What should social work, as a force of gradual social reform, do to this paradigm shift?
中国传统文化对社区支援网络手法的影响: 十年实务经验的反思
Authors: 叶 锦成 , 罗 崇安
Published: December 2009

基督教联会那打素社会服务辖下的爱邻中心从1991年到现在，十年以来一直沿用睦邻为本的自然支援网络手法 (Natural Locality Based Networking Approach)，去帮助在秀茂坪区的独居又长期患病的长者。经过十年多的理论和实践，这支援网络手法已日渐成熟。工作人员在与独居长者建立社区支援网络时发现，中国传统文化的社会取向(social orientation)如：家庭取向、关系取向、权威取向和他人取向的特色，不断影响著社区支援网络的建设过程。笔者就此对中国文化作出反思，并从实务案例中说明如何利用这些传统文化的特色去协助建立及推行社区支援网络。

Locality Based Networking Approach has been used for more than ten years by the United Christian Nethersole Community Health Services for supporting those lonely singleton disabled elderly in public housing. Thoughout these years of practical experience, the writers discovered that the formation and function of these social support networks were greatly affected by the Chinese social orientation, as suggested by Yang (1995). In this paper, the writers list all these culturally based practical experiences in details.
社会服务令的争议与再定位
Authors: 卢 铁荣
Published: December 2009

刑罚有不同的目的和作用，它们是：让罪犯补偿社会、复康、重投社会；使罪犯获得报应；阻吓他人；从社会移除害群之马，如监禁。前三者正是社会服务令的目的，它旨在协助罪犯补偿社会，从而改过自新和重投社会怀抱。而在谢霆锋案中，後三者却是很多社会人士所强烈要求的惩罚目的。为了避免日後再有类似的争论发生，社会服务令的重新定位是刻不容缓的。确立社会服务令为短期监禁的代替刑及订立清楚的换算方式，不但会减少争议，也能增加法庭的判刑选择，在扩大运用社区刑罚的同时，也能为上述各种惩罚目的找到更佳的平衡点，这将有助於我们迈向一个富有复和司法的社会。

Sentencing has various objectives and functions, including reparation, rehabilitation, reintegration, retribution, deterrence and removal from society, such as incarceration. Community service orders incorporate the first three functions. They assist offenders to make reparation to society for the crimes they have committed, to turn over a new leaf, and to reintegrate into society. In the case of singer Nicholas Tse, the last three functions were demanded by the community. To avoid similar conflicts in the future, to reposition community service orders is inevitable. There is an urgent need to reiterate community service orders as alternatives to imprisonment, and to establish a clear guideline for conversion between service hours and jail days. This approach would minimise conflicts in society, increase sentencing options and community penalties for the court, strike a balance between different penal goals, and strive for a restorative society.
MISSING OLDER PERSONS WITH DEMENTIA — A HONG KONG VIEW
Authors: LAI CLAUDIA K.Y. , CHUNG JENNY C.C. , WONG THOMAS K.S. , FAULKNER LAWRENCE W. , NG LOUISE , LAU LIAM K.P.
Published: December 2009

This paper reviews missing person incidents that occurred in older persons with dementia reported in local newspapers from 1 January 1999 to 1 May 2002. Ten relevant incidents, two of which happened to the same person, were found in WiseNews, an electronic database of 21 local newspapers. There were four (44%) males and five (56%) females with a mean age of 77 (standard deviation=5). In six (60%) cases, the missing persons eloped from home and four (40%) outside of home. Nine (90%) of the cases required less than a day to three days to locate the missing person. Six (60%) cases resulted in injuries or death due to falls or traffic accidents. It is not uncommon for dementia patients to get lost. Public awareness and understanding of the phenomenon is very important because the survival of missing persons depends on the implementation of timely and effective search and rescue. This analysis confirms the need for a prospective study to further examine the characteristics of missing older adults and missing incidents, as well as the search strategies adopted by caregivers.

这篇文章旨在回顾由一九九九年一月一日至二零零二年五月一日以来在本地报章上报导过的有关老年痴呆症患者走失的个案。WiseNews是一个包含二十一份本地报章的电子资料库。我们通过WiseNews搜索到十宗有关的报导，其中两宗个案发生在同一个患者身上。走失患者当中有四名男性，五名女性，年龄由七十到八十六岁［平均数：七十七］。在六宗［六成］走失个案当中，患者是从居所走失的，而另外四宗［四成］则发生在居所以外的地方。九宗［九成］个案需要少於一天至三天的时间去寻回走失患者。六宗［六成］个案涉及受伤或死亡。走失现象在老年痴呆症患者当中颇为普遍，走失患者的安危取决於及时和有效率的搜索及拯救策略。因此，大众需要对这现象有更多的了解。本文的分析显示本地需要对此问题作前瞻性的调查，使本地社会及健康服务从业员能掌握走失痴呆症患者的特徵，一般走失的情况及照顾者面对这问题的策略，从而提供合宜的协助。
Book Review: "香港青少年问题：廿一世纪初的现象、剖析与对策"，李永年
Authors: 李 德仁
Published: December 2009

未提供摘要。
DESIGNING WEB-BASED SOCIAL SERVICE PROGRAMMES: EXPERIENCE LEARNT FROM THE CYBER-PARENTING PROJECT
Authors: AU CHOR-FAI
Published: December 2009

As the home computer and the Internet are becoming more and more popular, social service agencies in Hong Kong are beginning to show interests in making use of the new technology to extend social welfare services to the community. This paper presents the results of an empirical study to evaluate the Cyber-Parenting Project as a pioneer attempt in providing parenting education through the Internet and gives recommendations for future attempts of similar nature. The discussion covers the conceptualisation, design, implementation and utility of the Cyber-Parenting Project, and the recommendations include issues on system design, provision, testing, and monitoring of web-based social service programs.

由於家用電腦及萬維網的應用日益普及，本港的社會服務機構亦開始思考如何應用這新科技去進一步延展社會福利服務到社區；而“Cyber親職教育網”便是利用萬維網去提供親職教育的一項創新計劃。本文就對該計劃進行的實證研究結果去評估該計劃在構思、設計、執行、及效用各方面的得失，並因應評估結果作出關乎系統設計、提供、測試、及監控等多方面的建議，供有興趣發展網上服務的福利機構及人仕參考。
SEX DIFFERENCES IN MENTAL HEALTH OF OLDER PEOPLE
Authors: LAI DANIEL W. L. , IP CONITA K. C.
Published: December 2009

This study examines the differences in mental health between older men and women. A cross-sectional telephone survey was conducted with a representative sample of 504 older adults aged 55 years and older. Mental health was measured by a revised Chinese version of the Geriatric Depression Scale and the Mental Component Summary (MCS) of a Chinese version of SF-36. Mental health differences between men and women were not identified, but gender was found to have an effect on mental health in the 54 to 64 age group, when being a female predicted a poorer status of mental health. The poorer financial status of women was the reason for the gender effect. Mental health predictors for men and women were also compared. The findings concluded that interventions to strengthen financial assistance for aging women were important for enhancing mental health.

這研究對五百零四名五十五歲或以上的長者進行電話調查。結果發現男、女長者精神健康差別在五十五至六十四歲的組別中顯示，較差的經濟狀況是影響女性精神健康的因素。比較男、女精神健康指標的結果顯示，經濟援助對強化女性精神健康的重要性。.