bluuebunny/crossref_metadata_2025 huggingface dataset:
Gas‐phase electrophilic fluorination of methanol by XeF+. Formation and characterization of protonated methyl hypofluorite and hypoxenite
Authors: Attinà Marina , Cacace Fulvio , Cartoni Antonella , Rosi Marzio
Published: August 2002

The reactivity of XeF+ ions towards methanol was investigated in the gas phase by a combination of mass spectrometric techniques and theoretical methods. The charged reagent, generated from the chemical ionization of xenon difluoride, undergoes both fluorine and xenon transfer to methanol, following dissociation of primary (CH3OH)XeF+ electrostatic adducts. Structural analysis performed by low‐energy collisionally activated dissociation and reactivity probing techniques, and the results of calculations carried out up to the B3LYP/CCSD(T) level of theory, concur in suggesting the formation of two different primary adducts of O—Xe—F and O—F—Xe connectivity that evolve into CH3O(H)Xe+ and CH3O(H)F+, upon loss of F and Xe, respectively. Evidence was obtained for the structure of the fluorinated species, identified as O‐protonated methyl hypofluorite. This finding allowed the first experimental evaluation of the proton affinity of CH3OF, which falls in the range 648.0–680.5 kJ mol−1, not inconsistent with the 644.8 kJ mol−1 value calculated at the CCSD(T) level and 298 K. The proton affinity of methyl hypoxenite, CH3OXe, was theoretically calculated to amount to 747.7 kJ mol−1. Copyright © 2001 John Wiley & Sons, Ltd.
Proteomics: the move to mixtures
Authors: Peng Junmin , Gygi Steven P.
Published: August 2002

Proteomics can be defined as the systematic analysis of proteins for their identity, quantity and function. In contrast to a cell's static genome, the proteome is both complex and dynamic. Proteome analysis is most commonly accomplished by the combination of two‐dimensional gel electrophoresis (2DE) and mass spectrometry (MS). However, this technique is under scrutiny because of a failure to detect low‐abundance proteins from the analysis of whole cell lysates. Alternative approaches integrate a diversity of separation technologies and make use of the tremendous peptide separation and sequencing power provided by MS/MS. When liquid chromatography is combined with tandem mass spectrometry (LC/MS/MS) and applied to the direct analysis of mixtures, many of the limitations of 2DE for proteome analysis can be overcome. This tutorial addresses current approaches to identify and characterize large numbers of proteins and measure dynamic changes in protein expression directly from complex protein mixtures (total cell lysates). Copyright © 2001 John Wiley & Sons, Ltd.
Localization of hepatitis B surface antigen epitopes present on variants and specifically recognised by anti‐hepatitis B surface antigen monoclonal antibodies
Authors: Jolivet‐Reynaud Colette , Lésenéchal Mylène , O'Donnell Barbara , Becquart Laurence , Foussadier Agnès , Forge Françoise , Battail‐Poirot Nicole , Lacoux Xavier , Carman William , Jolivet Michel
Published: August 2002

Small hepatitis B surface antigen (HBsAg) is considered to be the best marker for the diagnosis of Hepatitis B virus infection. However, HBsAg variants with mutations within the “a” determinant may be poorly or not detected by diagnostic assays. Three anti‐HBsAg monoclonal antibodies (6H6B6, 27E7F10, and 2G2G10), directed against conformational epitopes, were tested for their ability to detect the wild‐type HBsAg as well as variant forms and their respective epitopes were localised on the HBsAg sequence by using the phage‐displayed peptide library technology. Whereas 6H6B6 did not detect mutations T123N, S143L, D144A and G145R, 27E7F10 binding was affected by mutations P120T and G145R. In contrast, 2G2G10 reacted strongly with all tested variants including variant with the G145R mutation. Part of the 6H6B6 epitope was located in the major hydrophilic region (MHR) at residues 101–105, the 27E7F10 epitope (residues 214–219) was located near the C‐terminal end of the antigen and the 2G2G10 epitope at residues 199–208, within the theoretical fourth transmembrane helix. The 2G2G10 epitope localisation brings information about the HBsAg structure and the validity of established topological models. Finally, 2G2G10 is a valuable tool for HBsAg variant detection that is used as capture phase in a new bioMérieux diagnostic assay, which is currently in development. J. Med. Virol. 65:241–249, 2001. © 2001 Wiley‐Liss, Inc.
Evidence for persistence of parvovirus B19 DNA in livers of adults
Authors: Eis‐Hübinger Anna Maria , Reber Ulrike , Abdul‐Nour Thair , Glatzel Ulrich , Lauschke Holger , Pütz Uwe
Published: August 2002

Recent studies have suggested a pathogenic role of human parvovirus B19 (B19) in the development of acute fulminant liver failure in children. The hypothesis was based on the detection of B19 DNA in 8 of 10 explanted livers of children requiring liver transplantation. In the present study, explanted livers from 43 adults selected at random undergoing orthotopic liver transplantation for various reasons were examined. Pre‐transplant sera were available from 40 patients of whom 35 (88%) were anti‐B19 IgG‐seropositive. All but one serum were negative for anti‐B19 IgM antibody. By polymerase chain reaction, B19 DNA was detected in the livers of 15/35 (43%) anti‐B19 IgG‐positive patients, in 2/3 livers of patients with unknown anti‐B19 antibody status, and in the initial transplant of an anti‐B19 IgG‐positive patient who underwent liver retransplantation, and whose own liver was negative for B19 DNA. In a second study group, liver and bone marrow samples from 23 autopsied adults selected at random were tested. Serum specimens were available from 22 individuals, of whom 17 (77%) were anti‐B19 IgG‐seropositive. All sera were negative for anti‐B19 IgM antibody. B19 DNA was detected in the livers of 4/17 (24%) anti‐B19 IgG‐positive individuals, three of whom had also B19 DNA in their bone marrow. This is the first report demonstrating that B19 DNA is frequently present in livers of anti‐B19 seropositive adults suggesting persistence of B19 in the liver. Further studies are needed to address whether B19 is an innocent bystander in the liver or whether the presence of B19 in liver is of biological and clinical significance. J. Med. Virol. 65:395–401, 2001. © 2001 Wiley‐Liss, Inc.
Virological and serological analysis of rhinovirus infections during the first two years of life in a cohort of children
Authors: Blomqvist S. , Roivainen M. , Puhakka T. , Kleemola M. , Hovi T.
Published: August 2002

The occurrence of rhinovirus infections in a cohort of 329 children during the first 2 years of life was determined by virus detection and serological methods. Rhinovirus detection on nasopharyngeal aspirates and middle ear fluids comprised a combination of virus isolation in HeLa Ohio cells and a reverse transcription‐polymerase chain reaction (RT‐PCR)‐hybridization assay on the inoculated cell cultures. Nasopharyngeal aspirates were collected when the child was referred to the study clinic because of respiratory symptoms. Nasopharyngeal aspirates and middle ear fluids were collected after clinical diagnosis of an acute otitis media. Complement‐fixing antibodies to rhinovirus were determined from scheduled serum specimens collected at 6, 12, 18, and 24 months of age and from paired sera taken in the cases of acute otitis media. Rhinovirus infections were shown to be common in infants, 24% of the children had complement‐fixing antibodies at the age of 6 months and 22% had had at least one rhinovirus episode indicated by virus detection. At the age of 2 years, 91.3% of the children had rhinovirus‐specific antibodies, while 79% of the children had experienced rhinovirus infection as judged by the virus detection tests. However, the complement‐fixation assay was poor as a diagnostic test. Of 458 acute otitis media episodes studied, 41% were shown to be associated with a rhinovirus by RT‐PCR‐hybridization, while significant fourfold rise in rhinoviral antibodies was detected only in 7% of the cases. J. Med. Virol. 66:263–268, 2002. © 2002 Wiley‐Liss, Inc.
Concordance between semen‐derived HIV‐1 proviral DNA and viral RNA hypervariable region 3 (V3) envelope sequences in cases where semen populations are distinct from those present in blood
Authors: Curran Rebecca , Ball Jonathan K.
Published: August 2002

Sequence analysis of the third hypervariable region (V3) of the envelope gene of the HIV‐1 was carried out on HIV proviral and viral populations present in blood and semen. Phylogenetically distinct populations of virus were observed in three of the 10 patients analysed. Although the majority of the viruses were predicted to have an R5 phenotype, amino acid differences between blood and semen‐derived virus and provirus sequences were observed at sites previously shown to affect cell tropism. Importantly, the semen proviral population was representative of that observed for cell‐free virus. This indicates that seminal fluid mononuclear cells are possible sources for the cell‐free virus in found in semen. J. Med. Virol. 67:9–19, 2002. © 2002 Wiley‐Liss, Inc.
Tumor necrosis factor expressed by primary hippocampal neurons and SH‐SY5Y cells is regulated by α2‐adrenergic receptor activation
Authors: Renauld A.E. , Spengler R.N.
Published: August 2002

Neuron expression of the cytokine tumor necrosis factor‐α (TNF), and the regulation of the levels of TNF by alpha2‐adrenergic receptor activation were investigated. Adult rat hippocampal neurons and phorbol ester (PMA)‐differentiated SH‐SY5Y cells were examined. Intracellular levels of TNF mRNA accumulation, as well as TNF protein and that released into the supernatant were quantified by in situ hybridization, immunocytochemistry and bioanalysis, respectively. Both neuron cultures demonstrated constitutive production of TNF. Activation of the alpha2‐adrenergic receptor increased intracellular levels of TNF mRNA and protein in SH‐SY5Y cells after addition of graded concentrations of the selective agonist, Brimonidine (UK‐14304) to parallel cultures. Intracellular levels of mRNA were increased in a concentration‐dependent fashion within 15 min of UK‐14304 addition and were sustained during 24 hr of receptor activation. In addition, the levels of TNF in the supernatant were increased in both types of neuron cultures within 15 min of alpha2‐adrenergic receptor activation. Furthermore, levels of TNF significantly increased in the supernatants of both neuron cultures after potassium‐induced depolarization. A reduction in this depolarization‐induced release occurred in hippocampal neuron cultures after exposure to the sympathomimetic tyramine with media replacement to deplete endogenous catecholamines. This finding reveals a role for endogenous catecholamines in the regulation of TNF production. Potassium‐induced depolarization resulted in the release of TNF in hippocampal neuron cultures within 15 min but not until 24 hr in SH‐SY5Y cultures demonstrating a temporally mediated event dependent upon cell type. Neuron expression of TNF, regulated by alpha2‐adrenergic receptor activation demonstrates not only how a neuron controls its own production of this pleiotropic cytokine, but also displays a normal role for neurons in directing the many functions of TNF. © 2002 Wiley‐Liss, Inc.
The MAGE proteins: Emerging roles in cell cycle progression, apoptosis, and neurogenetic disease
Authors: Barker Philip A. , Salehi Amir
Published: August 2002

Since the identification of the first MAGE gene in 1991, the MAGE family has expanded dramatically, and over 25 MAGE genes have now been identified in humans. The focus of studies on the MAGE proteins has been their potential for cancer immunotherapy, as a result of the finding that peptides derived from MAGE gene products are bound by major histocompatibility complexes and presented on the cell surface of cancer cells. However, the normal physiological role of MAGE proteins has remained a mystery. Recent studies are now beginning to provide insights into MAGE gene function. Necdin acts as a cell cycle regulatory protein and plays a key role in the pathogenesis of Prader‐Willi syndrome, a neurogenetic disorder. MAGE‐D1, identified as a binding partner for the p75 neurotrophin receptor, the apoptosis inhibitory protein XIAP, and Dlx/MSX homeodomain proteins, blocks cell cycle progression and enhances apoptosis. This review provides an overview of the human MAGE genes and proteins, summarizes recent findings on their cellular roles, and provides a baseline for future studies on this intriguing gene family. © 2002 Wiley‐Liss, Inc.
Olfactory receptor expressed in ganglia of the autonomic nervous system
Authors: Weber Martina , Pehl Ulrich , Breer Heinz , Strotmann Jörg
Published: August 2002

Certain members of the olfactory receptor superfamily appear to be expressed not only in chemosensory neurons of the nasal epithelium. Analyzing the transgenic mouse line MOL2.3‐IGITL, the olfactory receptor subtype MOL2.3 was found to be expressed in distinct subpopulations of cells within a cranial, a cervical as well as within a thoracic ganglion. By means of coexpressed markers, the axonal processes of MOL2.3 expressing cells could be visualized and thus the target tissues innervated by these ganglionic neurons identified. Stained fibers, but no stained cell bodies were visible in distinct head regions, notably in the lateral nasal gland and in the so‐called Harderian gland; staining was also observed on distinct segments of blood vessels, especially within the tongue. In the thoracic region, the heart and a small segment of the aorta as well as a distinct population of lung alveoli were labeled by incoming blue fibers. Expression of MOL2.3 in cells of the autonomic nervous system supports the idea that at least some of the multiple olfactory receptor types serve functions others than odorant detection. © 2002 Wiley‐Liss, Inc.
Effect of endogenous β‐hydroxybutyrate on glucose metabolism in the diabetic rabbit brain: A 13C‐magnetic resonance spectroscopy study of [U‐13C]glucose metabolites
Authors: Lapidot A. , Haber S.
Published: August 2002

The neurological consequences of diabetes mellitus have recently been receiving greater attention in both clinical and experimental settings. The deleterious effect of hyperglycemia and altered oxidative substrate availability on the diabetic brain is the subject of many studies. The aim of the present study was to examine the effect of the altered metabolic environment, namely, hyperglycemia and hyperketonemia, on glucose metabolism in the diabetic brain. More specifically, we examined the effect of diabetes on the glucose flux via the pyruvate dehydrogenase (PDH) and pyruvate carboxylase (PC) pathways and subsequent metabolism in the tricarboxylic acid cycles in neurons and glia. To this end, [U‐13C]glucose was infused into the circulation of alloxan‐induced diabetic young adult rabbits, and the [13C]glucose metabolites were subsequently studied in brain extracts by 13C‐NMR. Significantly elevated brain glucose levels were found. In the hyperketonemic rabbits, elevated cerebral levels of β‐hydroxybutyrate (β‐HBA) were found. Alterations in the labeling patterns of glutamine in the hyperketonemic group lead to the conclusion that the elevated β‐HBA levels inhibit glucose metabolism, mostly in glia. This results in accumulation of glucose in the diabetic brain. In addition, altered levels of glutamine, glutamate, and GABA were also attributed to the effect of β‐HBA on brain metabolism. The possible role of these metabolic perturbations in causing neurological damage remains to be investigated. J. Neurosci. Res. 64:207–216, 2001. © 2001 Wiley‐Liss, Inc.
Structural dynamics of oligodendrocyte lysis by perforin in culture: Relevance to multiple sclerosis
Authors: Zeine Rana , Cammer Wendy , Barbarese Elisa , Liu Chau‐Ching , Raine Cedric S.
Published: August 2002

The mechanism by which oligodendrocytes are depleted from active lesions in multiple sclerosis (MS) is not clear but many reports implicate a cytolytic process. The most applied animal model for MS, chronic relapsing experimental autoimmune encephalomyelitis (EAE), has been established in inbred strains of mice, especially SJL and PL. Studies on oligodendrocytes from these strains in vitro have been hampered to date by an inability to grow these cells from mouse CNS tissue. We report here a successful method to culture SJL mouse oligodendrocytes and have analyzed lysis of these cells in vitro mediated by the pore‐forming protein, perforin, a candidate effector molecule in inflammatory demyelination. Cultures were exposed to murine perforin, 36–72 hemolytic U, for up to 2.5 hr and examined using the oligodendrocyte phenotypic markers O4, galactocerebroside and myelin basic protein (MBP), in addition to a membrane dye (DiI) and a marker of necrosis, propidium iodide, (PI). Cultures were imaged chronologically by phase contrast, immunofluorescence, digital, light and electron microscopy. Findings showed that the majority of oligodendrocytes were killed within 60–90 min via pore expansion and ultimately, membrane disruption. The structural features of the cellular damage comprised swelling of the cell body, fenestration and fragmentation of membranes and processes, cytoplasmic vacuolation and breakdown of the nuclear envelope. Astrocytes in the same system were relatively resistant to cell lysis. The above patterns of oligodendrocyte damage in SJL oligodendrocytes were reminiscent of patterns in the MS lesion, leaving us to conclude that perforin may play an important role in the human disease. J. Neurosci. Res. 64:380–391, 2001. © 2001 Wiley‐Liss, Inc.
Tau and HMW tau phosphorylation and compartmentalization in apoptotic neuronal PC12 cells
Authors: Shelton Shirley B. , Johnson Gail V.W.
Published: August 2002

In the Alzheimer disease brain, the microtubule‐associated protein tau is hyperphosphorylated. There is also evidence that apoptotic‐like processes may contribute to the neuronal loss in AD. In an apoptotic model that involves replating neuronal PC12 cells without serum and nerve growth factor (NGF), tau was hyperphosphorylated. During replating, however, neurites are removed. Here, differentiated cells were maintained in serum‐free media before growth factor removal, thus maintaining neuritic processes during the apoptotic process and allowing for evaluation of neuritic changes. Tau phosphorylation, evaluated by immunoblotting and immunocytochemistry, was compared with various measures of cell death. Compared with control, NGF‐deprived cells exhibited gradual and consistent increases of lactate dehydrogenase release over a 5‐day period and a peak of caspase‐3 activity at Day 2 after NGF removal. Nuclear staining demonstrated chromatin condensation in NGF‐deprived cells. Apoptotic cells had thickened, tortuous, and shortened neuritic processes compared with control cells. Immunoblotting showed an increase in both tau and high molecular weight (HMW) tau phosphorylation during the apoptotic process. Immunoreactivity of both tau isoforms shifted from the detergent insoluble cytoskeleton to the detergent soluble compartment in the apoptotic cells. The microtubule binding of both tau isoforms from apoptotic cells also was impaired. Immunoblotting of purified plasma membrane showed preferential association of HMW tau with the plasma membrane during apoptosis. Also, plasma membrane‐associated HMW tau was more phosphorylated during apoptosis. Immunocytochemistry demonstrated increased tau phosphorylation in most apoptotic cells, especially in the neurites. Tau was, however, dephosphorylated cells in the last stages of apoptosis. J. Neurosci. Res. 66:203–213, 2001. © 2001 Wiley‐Liss, Inc.
Job satisfaction and teamwork: the role of supervisor support
Authors: Griffin Mark A. , Patterson Malcolm G. , West Michael A.
Published: August 2002

The link between teamwork and job satisfaction was investigated in a sample of 48 manufacturing companies comprising 4708 employees. Two separate research questions were addressed. First, it was proposed that supervisor support would be a weaker source of job satisfaction in companies with higher levels of teamworking. Multilevel analysis indicated that the extent of teamwork at the company level of analysis moderated the relationship between individual perceptions of supervisor support and job satisfaction. Second, it was proposed that the extent of teamwork would be positively related to perceptions of job autonomy but negatively related to perceptions of supervisor support. Further, it was proposed that the link between teamwork and job autonomy would be explained by job enrichment practices associated with teamwork. Analyses of aggregated company data supported these propositions and provided evidence for a complex mediational path between teamwork and job satisfaction. Implications for implementing teamwork in organizations are discussed. Copyright © 2001 John Wiley & Sons, Ltd.
From knowledge accumulation to accommodation: cycles of collective cognition in work groups
Authors: Gibson Cristina B.
Published: August 2002

A framework for collective cognition in the workplace is developed to provide guidance to groups, their leaders, and researchers interested in understanding and improving cognitive processes. First, phases of the process and elements essential at each phase are identified based on prior research. Next, a series of catalysts are proposed which help bring about potential movement through the phases. Propositions regarding these catalysts are suggested to demonstrate the verifiability of the framework and guide future research and practice. Copyright © 2001 John Wiley & Sons, Ltd.
Discriminating among organizational politics, justice, and support
Authors: Andrews Martha C. , Kacmar K. Michele
Published: August 2002

The discriminant validity of perceptions of organizational politics, organizational support, and procedural and distributive justice was examined as the distinctions between these variables have been blurred in past research. Results from a sample of 418 full‐time employees provided evidence of discriminant validity for these variables. First, structural equation modelling was used to isolate the best structural representation of these four variables. Then, six theoretically relevant predictors (i.e., leader–member exchange, centralization, formalization, co‐worker cooperation, role conflict, and locus of control) were examined in an effort to provide further conceptual separation. Five of the six antecedents distinguished among politics, justice, and support. Suggestions for additional research that can shed light on the distinctions and similarities of these variables are offered based on the results of this study. Copyright © 2001 John Wiley & Sons, Ltd.
Relationships between tropical cyclone attributes and precipitation totals: considerations of scale
Authors: Konrad Charles E. , Meaux Melanie F. , Meaux David A.
Published: August 2002

In this study, a heavy rain climatology is constructed that relates precipitation totals estimated over a range of spatial scales (i.e. circular regions from 2500 to 500 000 km2) to tropical cyclone attributes. To carry this out, an automated algorithm is developed that identifies 2 day precipitation totals across the Cooperative Observer Network and estimates the greatest precipitation amounts over each spatial scale for all events from 1950 through to 1996. These maximum mean precipitation amounts are related to the tropical cyclone attributes of strength, size, and speed of movement. The resulting relationships are found to vary significantly according to the scale of precipitation. Precipitation amounts over the largest scales are most highly associated with the size of tropical cyclones, and precipitation amounts over the smallest scales are most highly connected with the speed of movement of the tropical cyclones. Copyright © 2002 Royal Meteorological Society.
Late Quaternary sea‐surface conditions at DSDP Hole 594 in the southwest Pacific Ocean based on dinoflagellate cyst assemblages
Authors: Marret Fabienne , de Vernal Anne , Benderra Ferial , Harland Rex
Published: August 2002

Investigation of organic‐walled dinoflagellate cyst distribution in 118 surface sediments from the Southern Ocean documents the relatively high diversity of cyst taxa (46 species) and distinct cyst assemblages in relation to surface water masses and temperature gradient. The Antarctic Water is characterised by the dominance of Selenopemphix antarctica accompanied by Brigantedinium spp. and Impagidinium pallidum. The Subantarctic Water association consists mainly of Nematosphaeropsis labyrinthus, Impagidinium paradoxum and Impagidinium sphaericum, whereas the Subtropical Water association is dominated by Operculodinium centrocarpum and Spiniferites membranaceus.

Multivariate analyses (non‐metric multidimensional scaling) demonstrate the relationships with sea‐surface conditions and enable the application of the best analogue method on the Southern Ocean dinoflagellate cyst data base for reconstructing past sea‐surface conditions. The dinoflagellate cyst record from DSDP 594 (45°31.41'S, 174°56.88'E; 1204 m, southern margin of the Chatham Rise) shows important fluctuations in species composition from glacial to interglacial over the last 140 000 yr. Reconstruction of winter and summer SSTs reveals much lower temperature than present by 6 to 10 °C during marine oxygen isotope stages 6, 4 and 2, and higher temperature by 2–3 °C during substage 5e. Copyright © 2001 John Wiley & Sons, Ltd.
Picosecond transient resonance Raman study on the excited‐state conformational dynamics of a highly ruffled nickel porphyrin
Authors: Jeong Dae Hong , Kim Dongho , Cho Dae Won , Jeoung Sae Chae
Published: August 2002

Picosecond to nanosecond transient resonance Raman spectroscopy was applied to track down the excited‐state conformational excursions of NiIIT(t‐Bu)P [nickel(II) 5,10,15,20‐tetra‐tert‐butylporphyrin] in various solvents with different dielectric properties. From the resonance Raman spectra of NiIIT(t‐Bu)P obtained by picosecond pulse photoexcitation, the α4‐type conformer was suggested to be dominant in the 1(d,d) excited state at the initial stage of deactivation processes (∼3 ps). However, only one conformer of αβαβ type was found to persist on the nanosecond time‐scale. We also observed that the initial formation of the 1(d,d) excited state of NiIIT(t‐Bu)P from the 1(π,π*) excited state is independent of the solvent, but the subsequent decay of the 1(d,d) to the ground state is strongly solvent dependent. Copyright © 2001 John Wiley & Sons, Ltd.
Temperature‐dependent Raman study of taurine single crystal
Authors: Lima R. J. C. , Freire P. T. C. , Sasaki J. M. , Melo F. E. A. , Mendes Filho J. , Moreira R. L.
Published: August 2002

Polarized Raman spectra of an oriented taurine single crystal were studied at temperatures ranging from 7 to 300 K. The results show that several bands present a linewidth increase characteristic of anharmonic effects, and that the band related to the CSH torsional mode splits at low temperatures. An abrupt wavenumber jump of an external mode was associated with a phase transition undergone by the crystal between 250 and 260 K on cooling. A calorimetric investigation over the temperature range 173–308 K confirmed the existence of a first‐order phase transition (at 251 K, on cooling), with a temperature hysteresis of 21 K. Copyright © 2001 John Wiley & Sons, Ltd.
Visible and UV‐resonance Raman spectroscopy of model peptides
Authors: Schweitzer‐Stenner Reinhard
Published: August 2002

We review various visible and UV‐resonance Raman experiments on model peptides such as N‐methylacetamide and di‐ and triglycine which are aimed at exploring the structure and dynamics of these molecules. Whereas visible Raman spectroscopy probes the electronic ground state, the UV Raman technique is utilized additionally to obtain structural information about excited electronic states. This research is aimed at obtaining a spectroscopically determined force field, which can be transferred to polypeptides and proteins. We further argue that the capability of vibrational spectroscopy to probe the structure of peptides and proteins can be significantly improved by combining computational and spectroscopic studies on appropriate model peptides to calibrate wavenumbers and intensities of Raman and IR bands for the quantitative determination of structural parameters such as the dihedral angles. Copyright © 2001 John Wiley & Sons, Ltd.
Creative strategic thinking and the analytical process: critical factors for strategic success
Authors: Hussey David
Published: August 2002

This article looks at the

Interrelationship of analysis and creative thinking, which are two of the five factors previously identified as critical for strategic success.

Shows how a deficiency of either factor can lead to defective strategies.

Suggests that analysis is not always objective, and that it can be heavily influenced by behavioural considerations.

Examines other issues in analysis and the role of techniques.

Copyright © 2001 John Wiley & Sons, Ltd.
Business strategies for entrepreneurial small firms
Authors: Anderson Alistair R. , Atkins Martin H.
Published: August 2002

This paper addresses the issue of the nature and context of business strategies in entrepreneurial small firms.

It examines a number of existing models of strategic planning and suggests that they cannot adequately cope with environmental uncertainty.

Developing the idea that effective strategy formation is processual in a stochastic environment, the paper proposes four alternative high‐level approaches (Meta strategies) entrepreneurial firms might use to cope with uncertainty.

These stress the notion of evolution as a direction rather than a series of staged events. Copyright © 2001 John Wiley & Sons, Ltd.
The PSE model: entry into emerging markets
Authors: Pehrsson Anders
Published: August 2002

This article presents a new international market entry model—the PSE model.

The model comprises three interrelated components that reflect premises external and internal to the firm: perceived barriers to entry (P), strategy competence (S) and entry strategy (E).

Propositions about the nature of the linkages between the model components are examined.

The model and its linkages are illustrated using Ericsson's entry into the emerging market of mobile telephony systems in the United States.

The application of the model enhances our understanding of entry into international emerging markets.

Practical suggestions in the application of the model are presented.

Copyright © 2002 John Wiley & Sons, Ltd.
12‐Lipoxygenase activity in the muscle tissue of Atlantic mackerel (Scomber scombrus) and its prevention by antioxidants
Authors: Saeed Suhur , Howell Nazlin K
Published: August 2002

Lipoxygenase was prepared from Atlantic mackerel muscle using differential centrifugation, ammonium sulphate precipitation and gel permeation (phenyl Sephadex G‐50) column chromatography. The crude lipoxygenase enzyme preparation was characterised by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE), which showed two prominent bands with molecular weights of 119 and 125 kDa. Fractions collected from the chromatography column were tested for enzyme activity by reacting with arachidonic acid and determining the production of hydroxyeicosatetraenoic acid (12‐HETE) using reverse phase HPLC and GC–MS. The 12‐HETE peak was absent from the fresh arachidonic acid control sample and from arachidonic acid treated with heat‐inactivated lipoxygenase. Esculetin, a known inhibitor of lipoxygenase, inhibited the production of 12‐HETE from the reaction of lipoxygenase with arachidonic acid, thus confirming that the enzyme was lipoxygenase. The HETE peak was partially reduced in the presence of antioxidants, namely synthetic butylated hydroxytoluene (BHT) and natural antioxidants vitamins C and E. The presence of lipoxygenase in Atlantic mackerel muscle indicates the possibility that the lipid oxidation mechanism is initiated enzymatically in chilled and frozen stored fillets of mackerel and that this oxidative deterioration could be inhibited by antioxidants (BHT, vitamins C and E) which are used widely in the food industry.

© 2001 Society of Chemical Industry
Statistical validation of sensory data: a study on wine
Authors: Carlucci Angela , Monteleone Erminio
Published: August 2002

A methodological procedure involving an appropriate statistical validation of sensory data was defined in order to describe the typical sensory profile of a young red wine (Aglianico) destined to aging. A trained panel of eight assessors rated the intensity of nine attributes on 16 products. Sensory data were submitted to statistical validation using a procedure organised in three main steps, namely fixed and mixed models of analysis of variance (ANOVA) and data standardisation. Results of the fixed ANOVA model computed on raw data showed significant differences between the products for all the attributes except cherry aroma and pungent mouthfeel. However, the results showed inconsistency between assessors. For many attributes, interaction effects were found. When individual differences between assessors were minimised or eliminated using scaled data, results of the fixed and mixed models showed no significant differences (p ≤ 0.05) amongst the products for any of the sensory attributes. Therefore the differences amongst the products before data handling and before applying the mixed model of ANOVA were due to the assessors' variability. The results after statistical validation showed that the wines are very similar and that all the attributes used to describe the sensory characteristics of the products can be considered, at a qualitative and a quantitative level, as typical descriptors of the Aglianico wine destined to aging.

© 2001 Society of Chemical Industry
Effects of processing and storage on walnut (Juglans regia L) tannins
Authors: Sze‐Tao Kar Wai Clara , Schrimpf Julie E , Teuber Suzanne S , Roux Kenneth H , Sathe Shridhar K
Published: August 2002

Walnut tannins were maximally extracted with absolute methanol and an extraction time of 60 min. Storage (21 days at 25 °C) significantly reduced (20–40% reduction) the assayable tannin content in walnuts. The ranges of tannin content in freshly cracked inshell and shelled walnuts were respectively 372–1095 and 363–667 mg catechin equivalent per 100 g dry weight. The assayable tannin content in inshell and shelled walnuts was 10–20% higher when the particle size was reduced from 2‐ to 8‐mesh. Using 0.5 as compared to 2% (w/v) vanillin as colour development reagent yielded 15–20% higher assayable tannin contents. The assay colour development reached a maximum after 20 min of incubation at 25 °C. Roasting (204 °C for 5 min) caused a small (14%) but significant reduction in assayable tannins. Soaking in aqueous alkali solutions was more effective (44–100% reduction) than soaking in aqueous acid solutions (6–76% reduction) in decreasing the assayable tannin content in walnuts. Microwave heating in distilled deionised water resulted in 93–98% reduction in walnut assayable tannins. Blanching at 100 °C for 2 min was as effective as alkali soaking in significantly reducing the amount of extractable walnut tannins (98% reduction). The tannin content in blanched walnuts was positively related to astringency scores (r  = 0.92).

© 2001 Society of Chemical Industry
Effect of calcium on mineral nutrient uptake and growth of tobacco
Authors: López‐Lefebre Luis R , Rivero Rosa M , García Pablo C , Sánchez Esteban , Ruiz Juan M , Romero Luis
Published: August 2002

The aim of this work was to analyse the dynamics of the nutritional state and biomass production in tobacco plants resulting from the application of various calcium levels (Ca1, 1.25 mol m−3 CaCl2; Ca2, 2.50 mol m−3 CaCl2; Ca3, 5 mol m−3 CaCl2) in the culture medium. Tobacco plants were grown under controlled conditions and submitted to regular fertilisation with macro‐ and micronutrients. The concentrations of Ca, organic N, P, K, Na, Mg, Fe, Mn, Zn, Cu, Cl and B were determined in the roots and leaves. As expected, Ca accumulated progressively with increasing concentration of this element in the culture medium. There was a slight rise in the concentration of organic N but hardly any change in the concentrations of K and Na. In contrast, increasing Ca application caused a gradual decline in P and Mg concentrations. In terms of micronutrient concentrations, Fe, Mn, Zn, Cl and B were influenced positively by Ca treatment. A noteworthy synergetic relationship was found between Ca and B. In contrast, the Cu concentration in the roots declined significantly with increasing Ca application. The effect of Ca on biomass production depended on the organ analysed, since the dry matter content diminished in the roots but was augmented slightly in the leaves.

© 2001 Society of Chemical Industry
Concentrated preoperative radiotherapy for resectable gastric cancer: 20‐years follow‐up of a randomized trial
Authors: Skoropad Vitali , Berdov Boris , Zagrebin Vasili
Published: August 2002

Background and Objectives

The role of radiation therapy in resectable gastric cancer is questionable. To study the value of concentrated preoperative radiotherapy, a randomized clinical trial had been carried out.

Methods

From 1974 to 1978, 152 patients were randomized and underwent exploratory laparotomy; in 50 patients curative surgery was not possible, while 102 patients satisfied protocol requirements and entered in the trial. Patients in the experimental group were treated with preoperative radiotherapy (20 Gy/5 days) and subtotal or total gastrectomy. Patients in the control group underwent surgery alone.

Results

Study showed acceptable tolerance of radiotherapy regime with no increase of postoperative mortality and morbidity. There was no significant difference in survival between the two treatment groups (χ2 = 0.349, df = 1, P = 0.555). Subset analysis also failed to demonstrate significant survival advantages of the combined treatment; however, some positive trends were seen in patients with locally advanced gastric cancer.

Conclusions

Concentrated preoperative radiotherapy in the dose of 20 Gy is safe and feasible, but seems to be insufficient to improve survival in gastric cancer patients. However, the results are promising in selected subgroups of patients, which encourages future trials with adjuvant radiation therapy. J. Surg. Oncol. 2002;80:72–78. © 2002 Wiley‐Liss, Inc.
Ethanol pyrolysis experiments in a variable pressure flow reactor
Authors: Li Juan , Kazakov Andrei , Dryer Frederick L.
Published: August 2002

Experimental profiles of stable species concentrations are reported for pyrolysis of ethanol in a variable‐pressure flow reactor at initial temperatures near 950 K and at constant pressures ranging from 3 to 12 atm. We present a new technique for comparison of model predictions with experimental observations in order to overcome the problem that time shifting of zero‐dimensional modeling results cannot accommodate the memory effects resulting from phenomena that occur in the mixing–diffuser region in the experiments. Using this new technique, comparison of the experiments with the recent ethanol kinetic model of Marinov shows that the model underestimates the fuel consumption rate and the yields of H2O and C2H4, the main products of ethanol decomposition, as well as CH3HCO and CH4, species related to abstraction channels. Both decomposition and abstraction reactions require significant modifications to improve detailed modeling of ethanol pyrolysis at the conditions of the reported experiments. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 859–867, 2001
Knowledge management: raising the spectre of the cross‐cultural dimension
Authors: Holden Nigel
Published: August 2002

Practitioners and theorists of knowledge management are increasingly aware of the practice as an international activity, but the topic is seldom presented in its cross‐cultural dimensions. This paper argues that knowledge management in the global economy is a form of cross‐cultural management, but points out that the literature is vague on how to handle culture in its wider international manifestations. Among other things it is suggested that the division of knowledge into tacit and explicit may have limited applicability when knowledge is to be leveraged cross‐culturally. Researchers are cautioned about making use of still pervasive concepts of culture which are out of keeping with the workings of the knowledge economy. It is concluded that the key task of knowledge management is to foster and continually sophisticate collaborative cross‐cultural learning. But the point to bear in mind is that the essence of the cross‐cultural challenge is not about what to learn from each other, but how to learn. Copyright © 2001 John Wiley & Sons, Ltd.
Investigating interactive effects in the theory of planned behavior in a service‐provider switching context
Authors: Bansal Harvir S. , Taylor Shirley F.
Published: August 2002

This study examines whether a model of the theory of planned behavior (Ajzen, 1985) with interaction terms can adequately explain customer service provider switching behavior. Results from a survey of mortgage customers suggest that it does. Interactions between perceived behavioral control (PBC) and intentions, between perceived behavioral control and attitude, and between attitude and subjective norms were all significant predictors of switching intentions. Implications for the theory of planned behavior and its use in services marketing are discussed. © 2002 Wiley Periodicals, Inc.
Updating Heider's balance theory in consumer behavior: A Jewish couple buys a German car and additional buying–consuming transformation stories
Authors: Woodside Arch G. , Chebat Jean‐Charles
Published: August 2002

Consumer researchers describe Heider's (1958) balance theory without showing how the theory relates to recent theoretical developments in consumer behavior. Empirical examination of the theory is also lacking in consumer‐psychology literature. This article updates Heider's balance theory in consumer behavior by developing the theory's links to theories of perceptual, attitudinal, and behavior automaticity and controlled thinking (see Bargh, 1994; Bargh, Chen, & Burrows, 1996) and cognitive‐experiential self‐theory (Epstein, 1994). Propositions central for applying balance theory to consumer psychology link automatic‐controlled memory retrievals and storytelling of unbalanced (i.e., paradoxical) situations that stimulate further thinking and action. Research using storytelling (e.g., see Fischer, 1999; Schank, 1990) methods aids in examining these theory developments empirically. © 2001 John Wiley & Sons, Inc.
Perceptions of age–identity: A cross‐cultural inner‐age exploration
Authors: Barak Benny , Mathur Anil , Lee Keun , Zhang Yong
Published: August 2002

This article presents an exploratory and comparative study of the nature of cognitive and desired age perceptions among 20–59‐year‐old men and women in three East Asian societies: India, Korea, and China. Research questions were posed about the role of gender and self‐identification with being either “young” or “middle‐aged.” The data indicate that gender plays no significant role in age perception in the three nations surveyed. The great majority of respondents under 40 considered themselves young and rejected a middle‐age role for themselves irrespective of their domicile. Also, young self‐identifiers' chronological and subjective ages were younger than those of middle‐age identifiers. These findings were surprisingly similar to those found in “ageless” American society. © 2001 John Wiley & Sons, Inc.
Antecedents of subjective age biases among senior women
Authors: Guiot Denis
Published: August 2002

From a conceptual framework based on developmental psychology, this research proposes testing an explanatory model of the trend to see oneself as younger, which is characteristic of seniors. The identification of antecedent variables of this tendency suggests a new approach to segmenting the feminine over‐50 market in France. © 2001 John Wiley & Sons, Inc.
Decision theory and real estate investment: an analysis of the decision‐making processes of real estate investment fund managers
Authors: French Nick
Published: August 2002

Decision theory is the study of models of judgement involved in, and leading to, deliberate and (usually) rational choice. In real estate investment, there are models for the pricing and allocation of assets. These asset allocation models suggest an optimum allocation between the respective asset classes based on retrospective judgements of performance and risk. The representation and role of real estate in a multi‐asset portfolio has, historically, been viewed in the context of portfolio theory. Real estate is selected, as other assets, on the basis of some criteria, e.g. commonly, its marginal contribution to the production of a mean‐variance efficient multi‐asset portfolio, subject to the investor's objectives and capital rationing constraints. However, decisions are made relative to current expectations and current business constraints. Whilst a decision‐maker may believe in the required optimum exposure levels, as dictated by an asset allocation model, the final decision may/will be influenced by factors outside the parameters of the mathematical model. The focus of decision theory is on the mathematical models. These may be probability based, loss functions, or other forms of statistical representations of judgements. Yet, much of decision theory does not lie entirely within any one discipline: it draws upon psychology, economics, mathematics, statistics, social sciences and many other areas of study. This paper discusses investors' perceptions and attitudes towards real estate, and highlights the important difference between theoretical exposure levels and pragmatic business considerations. The lynchpin in the decision‐making process is how investors perceive risk. The concept of risk plays a central role in various kinds of decision problems under uncertainty. It is possible that the definition of risk within an asset allocation model, where risk is equated with the uncertainty of achieving a specific required return, sits uncomfortably with the definition of risk used by the decision‐maker, where risk may equate to the consequence of not matching the performance of the competitors. In this paper, the author discusses the behavioural aspects of the decision‐making process for UK pension funds in their asset allocation role, and relates the various decision‐making models to the that process. Whilst the apparent question being asked is ‘how much should they invest in real estate?’, the answer achieved must be viewed in the context of what is pragmatically possible, or institutionally acceptable, with the constraints of business risk considerations. Copyright © 2001 John Wiley & Sons, Ltd.
Conspicuous consumption and the positional economy: policy and prescription since 1970
Authors: Mason Roger
Published: August 2002

In more recent years, the social significance of consumption has increased to such an extent that activity in the so‐called ‘positional economy’ is now seen to threaten prospects for sustainable, long‐term economic growth. In particular, the demand for status goods, fuelled by conspicuous consumption, has diverted many resources away from investment in the manufacture of more material goods and services in order to satisfy consumer preoccupations with their relative social standing and prestige. This paper looks at the policies and prescriptions which have been proposed in order to reduce levels of ‘conspicuous waste’ in the positional sector, and to redirect resources back into more productive economic activity. Copyright © 2000 John Wiley & Sons, Ltd.