Showing papers by "University College Cork published in 1998"
TL;DR: The Clustal series of programs as mentioned in this paper have been widely used for multiple alignment and for preparing phylogenetic trees, and the most popular of these programs is the Clusteral W 1.7.
2,682 citations
TL;DR: Prior to incorporating new strains into products their efficacy should be carefully assessed, and a case by case evaluation as to whether they share the safety status of traditional food-grade organisms should be made.
850 citations
TL;DR: It is concluded that, whereas the majority of bile salts‐resistant lactobacilli and bifidobacteria may be intrinsically sensitive to gastric transit, they are intrinsically resistant to small intestinal transit.
Abstract: An in vitro methodology which mimics in vivo human upper gastrointestinal transit was developed. The transit tolerance of potentially probiotic Lactobacillus and Bifidobacterium species was determined by exposing washed cell suspensions at 37°C to a simulated gastric juice (pH 2·0), containing pepsin (0·3% w/v) and sodium chloride (0·5% w/v), and a simulated small intestinal juice (pH 8·0), containing pancreatin USP (1 g l−1) and sodium chloride (5 g l−1), and monitoring changes in total viable count periodically. The methodology was also employed to determine the effect of adding milk proteins (1 g l−1), hog gastric mucin (1 g l−1) and soyabean trypsin-chymotrypsin inhibitor [SBTCI] (1 g l−1) on transit tolerance. The majority (14 of 15) of isolates lost >90% viability during simulated gastric transit. Only one isolate, Lactobacillus fermentum KLD, was considered intrinsically resistant. The addition of milk proteins, singly and in combination, generally improved gastric transit tolerance. In this regard, two isolates, Lact. casei 212.3 and Bifidobacterium infantis 25962, exhibited 100% gastric transit tolerance in the presence of milk proteins. In general, the addition of hog gastric mucin did not influence simulated gastric transit tolerance of lactobacilli but tended to increase that of bifidobacteria. However, it increased that of Lact. casei 242 and Lact. salivarius 43338 but diminished that of B. bifidum 2715 and B. animalis Bo. Selected bile salts-resistant isolates were intrinsically tolerant to simulated small intestinal transit. Only Lact. casei F19 and B. adolescentis 15703T showed significant reduction in viability after 240 min. In general, the addition of milk proteins and SBTCI did not affect simulated small intestinal transit tolerance. However, they significantly improved the intrinsic resistance of Lact. casei F19 but diminished that of B. breve 15700T. It is concluded that, whereas the majority of bile salts-resistant lactobacilli and bifidobacteria may be intrinsically sensitive to gastric transit, they are intrinsically resistant to small intestinal transit. In addition, it is postulated that milk proteins and mucin may function as both buffering agents and inhibitors of digestive protease activity in vivo, thereby protecting ingested bacterial strains during upper gastrointestinal transit.
748 citations
670 citations
TL;DR: The occurrence of a minority of lactobacilli with undesirable, atypical resistance to certain antibiotics demonstrates that not all strains are suitable for use as probiotics or bacteriotherapeutic agents.
471 citations
354 citations
TL;DR: It was found that both L. paracasei strains grew and sustained high viability in cheese during ripening, while each of the L. salivarius species declined over the ripening period, demonstrating that Cheddar cheese can be an effective vehicle for delivery of some probiotic organisms to the consumer.
Abstract: Cheddar cheese was manufactured with either Lactobacillus salivarius NFBC 310, NFBC 321, or NFBC 348 or L. paracasei NFBC 338 or NFBC 364 as the dairy starter adjunct. These five strains had previously been isolated from the human small intestine and have been characterized extensively with respect to their probiotic potential. Enumeration of these strains in mature Cheddar cheese, however, was complicated by the presence of high numbers (>10(7) CFU/g of cheese) of nonstarter lactic acid bacteria, principally composed of lactobacilli which proliferate as the cheese ripens. Attempts to differentiate the adjunct lactobacilli from the nonstarter lactobacilli based on bile tolerance and growth temperature were unsuccessful. In contrast, the randomly amplified polymorphic DNA method allowed the generation of discrete DNA fingerprints for each strain which were clearly distinguishable from those generated from the natural flora of the cheeses. Using this approach, it was found that both L. paracasei strains grew and sustained high viability in cheese during ripening, while each of the L. salivarius species declined over the ripening period. These data demonstrate that Cheddar cheese can be an effective vehicle for delivery of some probiotic organisms to the consumer.
286 citations
TL;DR: It is reported that native cytosolic Rabaptin‐5 is present in a homodimeric state and dimerization depends upon the presence of its coiled‐coil predicted sequences, and it is proposed that Rabapt in‐between two sequentially acting GTPases to coordinate endocytic and recycling traffic.
Abstract: Rabaptin-5 functions as an effector for the small GTPase Rab5, a regulator of endocytosis and early endosome fusion. We have searched for structural determinants that confer functional specificity on Rabaptin-5. Here we report that native cytosolic Rabaptin-5 is present in a homodimeric state and dimerization depends upon the presence of its coiledcoil predicted sequences. A 73 residue C-terminal region of Rabaptin-5 is necessary and sufficient both for the interaction with Rab5 and for Rab5-dependent recruitment of the protein on early endosomes. Surprisingly, we uncovered the presence of an additional Rabbinding domain at the N-terminus of Rabaptin-5. This domain mediates the direct interaction with the GTPbound form of Rab4, a small GTPase that has been implicated in recycling from early endosomes to the cell surface. Based on these results, we propose that Rabaptin-5 functions as a molecular linker between two sequentially acting GTPases to coordinate endocytic and recycling traffic.
228 citations
TL;DR: An overview of concepts and principles from the related philosophies of phenomenology and hermeneutics are provided and their application is illustrated in an interpretive case study on the information systems development process.
Abstract: There is increasing interest in hermeneutics as a research approach in the field of information systems. However, the problem facing researchers is that there is a paucity of information on the application of hermeneutics for empirical research in the social sciences; indeed, there is very little guidance on what exactly constitutes a hermeneutic method for the investigation of social phenomena. In order to address this problem, this paper provides an overview of concepts and principles from the related philosophies of phenomenology and hermeneutics; it then illustrates their application in an interpretive case study on the information systems development process. The insights obtained from the application of the hermeneutic method outlined in this paper have helped realize the study's objective of illustrating the link between phenomenological hermeneutics and the conduct of interpretive research.
217 citations
TL;DR: It would be more appropriate to recast the debate between ‘hard’ and ‘soft’ research approaches at a macro level in order to accommodate different research agenda and recognize the strengths within each tradition.
Abstract: The debate between ‘hard’ and ‘soft’ research approaches continues in the IS field, but with little prospect of resolution. The debate is typically characterized by tendentious arguments as advocates from each approach offer a somewhat one-sided condemnation of the counterpart from the inimical research tradition. This paper begins by relating two fictitious tales which serve to highlight the futility of research conducted at the extremity of each research approach. The dichotomies which characterize these rival factions are also summarized. The debate is then framed in terms of the polarization problem whereby IS researchers are divided geographically and paradigmatically into ‘hard’ and ‘soft’ camps. A variety of different strategies have been proposed for resolving the debate and these are discussed in detail. They are grouped into four categories, referred to as supremacism, isolationism, integration, and pluralism. Finally, the paper contends that the debate cannot be resolved, and offers the metaphor of magnetic polarity as a means of reflecting this. The paper concludes by arguing that it would be more appropriate to recast the debate at a macro level in order to accommodate different research agenda and recognize the strengths within each tradition.
198 citations
TL;DR: The results of scanning electron and confocal microscopy demonstrated that strain F113 and its derivatives adhered to G. mosseae spores independent of the ability to produce DAPG, a concentration that might be present in the rhizosphere.
Abstract: The arbuscular mycorrhizal symbiosis, a key component of agroecosystems, was assayed as a rhizosphere biosensor for evaluation of the impact of certain antifungal Pseudomonas inoculants used to control soil-borne plant pathogens. The following three Pseudomonas strains were tested: wild-type strain F113, which produces the antifungal compound 2,4-diacetylphloroglucinol (DAPG); strain F113G22, a DAPG-negative mutant of F113; and strain F113(pCU203), a DAPG overproducer. Wild-type strain F113 and mutant strain F113G22 stimulated both mycelial development from Glomus mosseae spores germinating in soil and tomato root colonization. Strain F113(pCU203) did not adversely affect G. mosseae performance. Mycelial development, but not spore germination, is sensitive to 10 mM DAPG, a concentration that might be present in the rhizosphere. The results of scanning electron and confocal microscopy demonstrated that strain F113 and its derivatives adhered to G. mosseae spores independent of the ability to produce DAPG.
TL;DR: In this article, the authors rationalized the unusual properties of nanoclusters, microparticles or quantum dots, and used them to rationalize the high level of catalytic activity of oxide-supported gold micro-articles.
Abstract: Chemistry Department, University College Cork, Ireland Although it is the noblest and most inert of metals, and is a very weak chemisorber, gold displays a very wide range of electrocatalytic activity — especially in base. Such unexpected behaviour is rationalized here in terms of the unusual properties of nanocluster, microparticles or quantum dots. Such species, present as defects at the metal surface, undergo oxidation at unusually low potentials (significantly lower than that of bulk gold) in a process known as premonolayer oxidation. The resulting low coverage (or incipient) oxide species are assumed to be the mediators for oxidation reactions while unoxidized active gold atoms, present at lower potentials, often act as the mediators for reduction. Electrocatalysis on noble metals is quite often confined to the double layer region and only low coverage metal atoms at active sites are involved. The enhanced activity of gold in base is readily rationalized in terms of a super-Nernstian E/pH effect. The unusual properties of metal nanoclusters may also be used to rationalize the surprisingly high level of catalytic activity of oxide-supported gold microparticles as reported recently by Haruta and co-workers.
TL;DR: The results suggest that lacticin 3147 is a pore-forming bacteriocin which acts on a broad range of gram-positive bacteria, including Listeria monocytogenes, and Bacillus subtilis.
Abstract: Lacticin 3147 is a broad-spectrum bacteriocin produced by Lactococcus lactis subsp. lactis DPC3147 (M. P. Ryan, M. C. Rea, C. Hill, and R. P. Ross, Appl. Environ. Microbiol. 62:612-619, 1996). Partial purification of the bacteriocin by hydrophobic interaction chromatography and reverse-phase fast protein liquid chromatography revealed that two components are required for full activity. Lacticin 3147 is bactericidal against L. lactis, Listeria monocytogenes, and Bacillus subtilis; at low concentrations of the bacteriocin, bactericidal activity is enhanced when target cells are energized. This finding suggests that the presence of a proton motive force promotes the interaction of the bacteriocin with the cytoplasmic membrane, leading to the formation of pores at these low lacticin 3147 concentrations. These pores were shown to be selective for K+ ions and inorganic phosphate. The loss of these ions resulted in immediate dissipation of the membrane potential and hydrolysis of internal ATP, leading to an eventual collapse of the pH gradient at the membrane and ultimately to cell death. Our results suggest that lacticin 3147 is a pore-forming bacteriocin which acts on a broad range of gram-positive bacteria.
Journal Article•
TL;DR: Findings suggest that CCR5-positive mononuclear cells, macrophages, and microglia contribute to disease progression in the central nervous system of children and adults with AIDS by serving as targets for virus replication.
Abstract: The chemokine receptors CCR5 and CXCR4 are co-receptors together with CD4 for human immunodeficiency virus (HIV)-1 entry into target cells. Macrophage-tropic HIV-1 viruses use CCR5 as a co-receptor, whereas T-cell-line tropic viruses use CXCR4. HIV-1 infects the brain and causes a progressive encephalopathy in 20 to 30% of infected children and adults. Most of the HIV-1-infected cells in the brain are macrophages and microglia. We examined expression of CCR5 and CXCR4 in brain tissue from 20 pediatric acquired immune deficiency syndrome (AIDS) patients in relation to neuropathological consequences of HIV-1 infection. The overall frequency of CCR5-positive perivascular mononuclear cells and macrophages was increased in the brains of children with severe HIV-1 encephalitis (HIVE) compared with children with mild HIVE or non-AIDS controls, whereas the frequency of CXCR4-positive perivascular cells did not correlate with disease severity. CCR5- and CXCR4-positive macrophages and microglia were detected in inflammatory lesions in the brain of children with severe HIVE. In addition, CXCR4 was detected in a subpopulation of neurons in autopsy brain tissue and primary human brain cultures. Similar findings were demonstrated in the brain of adult AIDS patients and controls. These findings suggest that CCR5-positive mononuclear cells, macrophages, and microglia contribute to disease progression in the central nervous system of children and adults with AIDS by serving as targets for virus replication.
TL;DR: Oncogenesis is promoted not by simply interfering with caspase-mediated apoptosis, but by preventing an upstream event which is defined as the commitment point for cell death.
Abstract: Apoptosis is a morphologically defined type of cell death associated with the activation of certain proteases belonging to the ICE/CED-3 family, known as caspases. Resistance to apoptosis has been implicated as one of the mechanisms that participates in oncogenesis. We found that the broad-spectrum peptide inhibitor of the caspases, zVAD-fmk, interferes in a dose-dependent way with all the morphological and biochemical changes associated with apoptosis induced by anti-CD95 mAb, staurosporine, VP-16 and Act-D. However, with the exception of anti-CD95-triggered apoptosis, the insulted cells lost their clonogenic potential, even when pre-treated with a high dose of zVAD-fmk. Under these circumstances, the dying cells displayed no signs of apoptosis, including activation of caspases, externalization of phosphatidylserine, nuclear condensation, or DNA fragmentation. Instead, this cell death was characterized by cytoplasmic and nuclear vacuolization followed by the loss of plasma membrane integrity. Thus, preventing the onset of apoptosis by blocking caspase activity did not rescue cells from dying in response to drugs such as staurosporine, VP-16 and Act-D. In comparison, ectopic expression of anti-apoptotic oncogenes such as bcl-2 and bcr-abl not only inhibited apoptosis but also preserved the clonogenic potential of the cells. Therefore, oncogenesis is promoted not by simply interfering with caspase-mediated apoptosis, but by preventing an upstream event which we define as the commitment point for cell death.
TL;DR: Data show that leucokinins act on stellate cells through intracellular calcium to increase transcellular chloride conductance through channels, as electrogenic cation conductance is confined to principal cells, and the two pathways are spatially segregated in this tissue.
Abstract: Anion conductance across theDrosophila melanogaster Malpighian (renal) tubule was investigated by a combination of physiological and transgenic techniques. Patch-clamp recordings identified cluster...
TL;DR: The completely sequenced pMRC01 plasmid provides important information about these industrially relevant phenotypes and gives insight into the structure, function and evolution of large Gram‐positive conjugative plasmids in general.
Abstract: The complete sequence of pMRC01, a large conjugative plasmid from Lactococcus lactis ssp. lactis DPC3147, has been determined. Using a shotgun sequencing approach, the 60 232 bp plasmid sequence was obtained by the assembly of 1056 underlying sequences (sevenfold average redundancy). Sixty-four open reading frames (ORFs) were identified. Analysis of the gene organization of pMRC01 suggests that the plasmid can be divided into three functional domains, with each approximately 20 kb region separated by insertion sequence (IS) elements. The three regions are (i) the conjugative transfer region, including a 16-gene Tra (transfer) operon; (ii) the bacteriocin production region, including an operon responsible for the synthesis of the novel bacteriocin lacticin 3147; and (iii) the phage resistance and plasmid replication region of the plasmid. The complete sequence of pMRC01 provides important information about these industrially relevant phenotypes and gives insight into the structure, function and evolution of large Gram-positive conjugative plasmids in general. The completely sequenced pMRC01 plasmid should also provide a useful framework for the design of novel plasmids to be incorporated into starter strain improvement programmes for the dairy industry.
TL;DR: The seal containing lacticin 3147 exhibited excellent antimicrobial activity and might form the basis of an improved treatment for the prevention of mastitis in dry cows.
Abstract: Lacticin 3147 is a broad-spectrum bacteriocin produced by Lactococcus lactis subsp. lactis DPC3147 which is bactericidal against a range of mastitis-causing streptococci and staphylococci. In this study, both lacticin 3147 and the lantibiotic nisin were separately incorporated into an intramammary teat seal product. The seal containing lacticin 3147 exhibited excellent antimicrobial activity and might form the basis of an improved treatment for the prevention of mastitis in dry cows.
TL;DR: The algorithm combines gradient-based optimization of nonlinear weights with singular value decomposition (SVD) computation of linear weights in one integrated routine, particularly effective for the LMN architecture where the linear to nonlinear parameter ratio is large.
Abstract: This paper presents a new hybrid optimization strategy for training feedforward neural networks. The algorithm combines gradient-based optimization of nonlinear weights with singular value decomposition (SVD) computation of linear weights in one integrated routine. It is described for the multilayer perceptron (MLP) and radial basis function (RBF) networks and then extended to the local model network (LMN), a new feedforward structure in which a global nonlinear model is constructed from a set of locally valid submodels. Simulation results are presented demonstrating the superiority of the new hybrid training scheme compared to second-order gradient methods. It is particularly effective for the LMN architecture where the linear to nonlinear parameter ratio is large.
TL;DR: The combined use of a phloroglucinol-producing P. fluorescens and a proteolytic S. maltophilia improved protection of sugar beet against Pythium-mediated damping-off when compared with single inoculations of either biocontrol strain.
Abstract: Pseudomonas fluorescens F113 and Stenotrophomonas maltophilia W81 protect sugar beet from Pythium-mediated damping-off through production of the antifungal secondary metabolite 2,4-diacetylphloroglucinol and extracellular proteolytic activity, respectively. In this study, the two biocontrol strains were combined in a consortium, with the objective of improving upon the level of protection achieved when using each strain singly. Growth and in vitro production of 2,4-diacetylphloroglucinol by F113 and extracellular lytic enzymes by W81 were not affected when inoculated in combination. The abilities of W81 and F113 to colonize the rhizosphere of sugar beet were essentially similar when the two strains were applied singly or coinoculated onto seeds in a 1 : 1 ratio, both in natural soil microcosms and under field conditions. Concomitantly, single inoculation with W81 or F113 effectively prevented colonization of sugar beet seeds by Pythium spp. in soil microcosms, without the necessity for combining both strains. However, this parity was not reflected in seed emergence where the combination of W81 and F113 significantly enhanced final sugar beet stands (to the level achieved with chemical pesticides) under microcosm conditions at 28 days after sowing. In a field experiment, the only inoculation treatment capable of conferring effective protection of sugar beet was that in which W81 and F113 were coinoculated, and this treatment proved equivalent to the use of chemical fungicides. In conclusion, when compared with single inoculations of either biocontrol strain, the combined use of a phloroglucinol-producing P. fluorescens and a proteolytic S. maltophilia improved protection of sugar beet against Pythium-mediated damping-off.
TL;DR: In this paper, the authors highlight areas of interest in the production of enzyme-modified cheese and highlight the best method for producing economic and consistent cheese flavors is through enzyme modified cheese production.
TL;DR: Interestingly, the data suggest a link between the caffeine threshold and tension values and the MH/CCD phenotype, and indicates that assessment of recombinant individuals on the basis of caffeine response is justified, whereas assessment on the based of halothane response may be problematic.
Abstract: Malignant hyperthermia (MH) is a pharmacogenetic disorder of skeletal muscle that is triggered in genetically predisposed individuals by common anesthetics and muscle relaxants. The ryanodine receptor (RYR1) is mutated in a number of MH pedigrees, some members of which also have central core disease (CCD), an inherited myopathy closely associated with MH. Mutation screening of 6 kb of the RYR1 gene has identified four adjacent novel mutations, C6487T, G6488A, G6502A, and C6617T, which result in the amino acid alterations Arg2163Cys, Arg2163His, Val2168Met, and Thr2206Met, respectively. Collectively, these mutations account for 11% of MH cases and identify the gene segment 6400-6700 as a mutation hot spot. Correlation analysis of the in vitro contracture-test data available for pedigrees bearing these and other RYR1 mutations showed an exceptionally good correlation between caffeine threshold and tension values, whereas no correlation was observed between halothane threshold and tension values. This finding has important ramifications for assignment of the MH-susceptible phenotype, in genotyping studies, and indicates that assessment of recombinant individuals on the basis of caffeine response is justified, whereas assessment on the basis of halothane response may be problematic. Interestingly, the data suggest a link between the caffeine threshold and tension values and the MH/CCD phenotype.
TL;DR: Exposure to UVA light at a dose intensity of 5.6 mW/cm2 for 4 h resulted in a significant decrease in CAT and SOD activities and a significant increase in TBARS, with astaxanthin exhibiting superior protective properties.
TL;DR: It is concluded that an understanding of the scientific principles and mechanisms involved in probiotic activities in the human host is continuing to emerge and advances will improve the basis upon which potentially probiotic microorganisms are selected and delivered by functional foods in the diet for specified human nutritional/health benefits.
Abstract: The selection of potentially probiotic microorganisms for use in functional dairy foods is reviewed. Two groups of selection criteria are distinguished encompassing technological and medico-scientific properties. The former ensure provision of viable cultures of the desired cell density that are robust to the intended product application, while the latter ensure that the culture provided possesses activity in terms of some specified nutritional/health benefit at a specified site in the gastrointestinal tract. It is concluded that an understanding of the scientific principles and mechanisms involved in probiotic activities in the human host is continuing to emerge. Further advances will require a concerted collaborative effort between medical, pharmacological, nutritional, microbiological and technological experts. These advances will improve the basis upon which potentially probiotic microorganisms are selected and delivered by functional foods in the diet for specified human nutritional/health benefits.
TL;DR: Four micro‐organism‐drug combinations were evaluated for β‐lactamase activity but its absence suggested that cell wall impermeability was responsible for cephalosporin resistance among bifidobacteria.
Abstract: Sixteen Bifidobacterium isolates from the human gastrointestinal tract were assayed for susceptibility to 44 antibiotics by soft agar overlay disc diffusion on TPY agar. Five isolates (3/7 B. bifidum and 2/3 B. breve) exhibited atypical antibiotic susceptibility profiles. Poor growth in the agar overlay accounted for susceptibility of B. bifidum but not B. breve isolates. All other isolates were resistant to cefoxitin (30 micrograms), aztreonam (30 micrograms), vancomycin (30 micrograms), amikacin (30 micrograms), gentamicin (10 micrograms), kanamycin (30 micrograms), streptomycin (10 micrograms), fusidic acid (10 micrograms), trimethoprim (5 micrograms), norfloxacin (10 micrograms), nalidixic acid (30 micrograms), metronidazole (5 micrograms), polymyxin B (300 micrograms) and colistin sulphate (10 micrograms), and they were susceptible to the six penicillins studied, cephalothin (30 micrograms), cefuroxime (30 micrograms), cefaclor (30 micrograms), ceftizoxime (30 micrograms), cefotaxime (30 micrograms), bacitracin (10 micrograms), chloramphenicol (30 micrograms), erythromycin (15 micrograms), clindamycin (2 micrograms), rifampicin (5 micrograms) and nitrofurantoin (300 micrograms). In addition, they varied in their susceptibility to cephradine (30 micrograms), cephazolin (30 micrograms), cefoperazone (75 micrograms), ceftriaxone (30 micrograms), ofloxacin (5 micrograms) and furazolidone (15 micrograms). They were resistant, or only marginally moderately susceptible, to ceftazidime (30 micrograms), netilmicin (10 micrograms), sulphamethoxazole (100 micrograms), cotrimoxazole (25 micrograms) and ciprofloxacin (5 micrograms), and susceptible or marginally moderately susceptible to tetracycline (30 micrograms). All B. bifidum isolates were susceptible to cefixime (5 micrograms). Four microorganism-drug combinations were evaluated for beta-lactamase activity but its absence suggested that cell wall impermeability was responsible for cephalosporin resistance among bifidobacteria. The antibiotic susceptibility of B. animalis 25527T was similar to that of the human isolates.
TL;DR: Overall, the results showed that increasing the monounsaturated profile of chicken meat lipids did not adversely affect quality characteristics and dietary alpha-tocopherol supplementation was a more important factor in the determination of broiler meat quality.
Abstract: 1. The effect of dietary fat and vitamin E supplementation on quality attributes (drip loss, oxidative stability, sensory quality) in chicken meat and meat products was investigated. Broiler chicks were fed on diets containing tallow (60 g/kg) or olive oil (60 g/kg) at a basal (30 mg/kg diet) or supplemental (200 mg/kg diet) concentration of alpha-tocopheryl acetate for 8 weeks. The alpha-tocopherol content and fatty acid composition of breast and thigh meat was determined. Drip loss was determined in breast fillets. Lipid oxidation (thiobarbituric acid-reacting substances/TBARS) and sensory quality (warmed-over flavour development/WOF) were assessed in minced thigh meat during storage. 2. Dietary olive oil increased the ratio of monounsaturated to saturated fatty acids (MUFA/SFA) in the diets. In breast and thigh, this resulted in approximately a two-fold increase in the MUFA/SFA ratio. Supplemental alpha-tocopherol increased the alpha-tocopherol content of muscles. 3. Dietary fat did not influence drip ...
13 Dec 1998
TL;DR: The debate between “hard” positivist and “soft” interpretivist research approaches has been the subject of much discussion in the IS field and a number of strategies for resolving the issue are considered.
Abstract: The debate between “hard” positivist and “soft” interpretivist research approaches has been the subject of much discussion in the IS field. Typically, the debate is framed in issues central to the philosophy of science, an area where relatively few IS researchers are truly competent. This paper attempts to illuminate the issue, particularly for students and researchers not entirely familiar with the arguments. The opposing positions are caricatured in two anecdotes which illustrate the futility of research conducted at the cul de sac extremes of each approach. The main dichotomies characteristic of each research tradition are then summarized and categorized according to various levels, namely, paradigmatic, ontological, epistemological, methodological, and axiological. Finally, the paper considers a number of strategies for resolving the
TL;DR: A variety of nutrient and non-nutrient dietary constituents, including vitamins C, E and carotenoids, have been shown to affect this prooxidant/antioxidant balance and consequent risk of certain degenerative diseases.
01 Oct 1998
TL;DR: A 60-item questionnaire was developed following a factor model used with success for conventional software evaluation and it was shown that the questionnaire results agreed with and amplified the other data.
Abstract: User-based satisfaction questionnaires have so far been little used in the evaluation of web sites. A 60-item questionnaire was developed following a factor model used with success for conventional...
TL;DR: In this paper, the crystal structures of six cation distortion isomers of the [Cu(phen)2Br][Y] series of complexes were determined by X-ray diffraction.
Abstract: The crystal structures of [Cu(phen)2Br][Br]·H2O (1, phen = 1,10-phenanthroline), [Cu(phen)2Br][ClO4] (2), [Cu(phen)2Br][NO3]·H2O (3), [Cu(phen)2Br][PF6] (4), and [Cu(phen)2Br][BPh4] (5) have been determined by X-ray diffraction. Four of the complexes, 1−4, have a CuN4Br chromophore with a square based pyramidal distorted trigonal bipyramidal (SBPDTB) stereochemistry, while 5 involves an extreme trigonal bipyramidal distorted square based pyramidal (TBDSBP) stereochemistry. The geometries of the CuN4Br chromophores in 1−5 are compared by scatter plot analysis with a single [Cu(phen)2Br][ClO4] complex, 6, of known crystal structure involving a crystallographic 2-fold axis of symmetry. The distortion isomers of 2 and 6 are significantly different. The scatter plots of the six cation distortion isomers of the [Cu(phen)2Br][Y] series of complexes suggest that all six complexes lie on a common structural pathway, involving a mixture of the symmetric, νsym, C2 mode and the asymmetric, νasym, non-C2 mode of vibra...