881 resultados para Evaluation Studies


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Cooper, J., Spink, S., Thomas, R. & Urquhart, C. (2005). Evaluation of the Specialist Libraries/Communities of Practice. Report for National Library for Health. Aberystwyth: Department of Information Studies, University of Wales Aberystwyth. Sponsorship: National Library for Health (NLH)

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Yeoman, A. J., Cooper, J. M., Urquhart, C. J. & Tyler, A. (2003). The management of health library outreach services: evaluation and reflection on lessons learned on the VIVOS project. Journal of the Medical Library Association, 91(4), 426-433. Sponsorship: Resource

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Rowley, J.& Urquhart, C. (2007). Understanding student information behavior in relation to electronic information services: lessons from longitudinal monitoring and evaluation Part 1. Journal of the American Society for Information Science and Technology, 58(8), 1162-1174. Sponsorship: JISC

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Urquhart, C. & Rowley, J. (2007). Understanding student information behavior in relation to electronic information services: lessons from longitudinal monitoring and evaluation Part 2. Journal of the American Society for Information Science and Technology, 58(8), 1188-1197. Sponsorship: JISC

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A bacteriocin-producing strain of Lactobacillus paracasei DPC 4715 was used as an adjunct culture in Cheddar cheese in order to control the growth of “wild” nonstarter lactic acid bacteria. No suppression of growth of the indicator strain was observed in the experimental cheese. The bacteriocin produced by Lactobacillus paracasei DPC 4715 was sensitive to chymosin and cathepsin D and it may have been cleaved by the rennet used for the cheese manufactured or by indigenous milk proteases. A series of studies were performed using various microbial adjuncts to influence cheese ripening. Microbacterium casei DPC 5281, Corynebacterium casei DPC 5293 and Corynebacterium variabile DPC 5305 were added to the cheesemilk at level of 109 cfu/ml resulting in a final concentration of 108 cfu/g in Cheddar cheese. The strains significantly increased the level of pH 4.6-soluble nitrogen, total free amino acids after 60 and 180 d of ripening and some individual free amino acids after 180 d. Yarrowia lipolytica DPC 6266, Yarrowia lipolytica DPC 6268 and Candida intermedia DPC 6271 were used to accelerate the ripening of Cheddar cheese. Strains were grown in YG broth to a final concentration of 107 cfu/ml, microfluidized, freeze-dried and added to the curd during salting at level of 2% w/w. The yeasts positively affected the primary, secondary proteolysis and lipolysis of cheeses and had aminopeptidase, dipeptidase, esterase and 5’ phosphodiestere activities that contributed to accelerate the ripening and improve the flavor of cheese. Hafia alvei was added to Cheddar cheesemilk at levels of 107 cfu/ml and 108 cfu/ml and its contribution during ripening was evaluated. The strain significantly increased the level of pH 4.6-soluble nitrogen, total free amino-acids, and some individual free amino-acids of Cheddar cheese, whereas no differences in the urea-polyacrylamide gel electrophoresis (urea-PAGE) electrophoretograms of the cheeses were detected. Hafia alvei also significantly increased the level of some biogenic amines. A low-fat Cheddar cheese was made with Bifidobacterium animalis subsp. lactis, strain BB-12® at level of 108 cfu/ml, as a probiotic adjunct culture and Hi-Maize® 260 (resistant high amylose maize starch) at level of 2% and 4% w/v, as a prebiotic fiber which also played the role of fat replacer. Bifidobacterium BB-12 decreased by 1 log cycle after 60 d of ripening and remained steady at level of ~107 cfu/g during ripening. The Young’s modulus also increased proportionally with increasing levels of Hi-maize. Hencky strain at fracture decreased over ripening and increased with increasing in fat replacer. A cheese based medium (CBM) was developed with the purpose of mimicking the cheese environment at an early ripening stage. The strains grown in CBM showed aminopeptidase activity against Gly-, Arg-, Pro- and Phe-p-nitroanalide, whereas, when grown in MRS they were active against all the substrates tested. Both Lb. danicus strains grown in MRS and in CBM had aminotransferase activity towards aromatic amino acids (Phe and Trp) and also branched-chain amino acids (Leu and Val). Esterase activity was expressed against p-nitrophenyl-acetate (C2), pnitrophenyl- butyrate (C4) and p-nitrophenyl-palmitate (C16) and was significantly higher in CBM than in MRS.

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The Silurian-Devonian Galway Granite Complex (GGC ~425-380Ma) is defined here as a suite of granitoid plutons that comprise the Main Galway Granite Batholith and the Earlier Plutons. The Main Batholith is a composite of the Carna Pluton in the west and the Kilkieran Pluton in the east and extends from Galway City ~130km to the west. The Earlier Plutons are spatially, temporally and structurally distinct, situated northwest of the Main Batholith and include the Roundstone, Omey, Inis and Letterfrack Plutons. The majority of isotopic and structural data currently available pertain to the Kilkieran Pluton, several tectonic models have already been devised for this part of the complex. These relate emplacement of the Kilkieran Pluton to extension across a large east-west Caledonian lineament, i.e. the Skird Rocks Fault, during late Caledonian transtension. No chronological data have been published that directly and accurately date the emplacement of the Carna Pluton or any of the Earlier Plutons. There is also a lack of data pertaining to the internal structure of these intrusions. Accordingly, no previous study has established the mechanisms of emplacement for the Earlier Plutons and only limited work is available for the Carna Pluton. As a consequense of this, constituents of the GGC have not previously been placed in a context relative to each other or to regional scale Silurio-Devonian kinematics. The current work focuses on the Omey, Roundstone and Carna Plutons. Here, results of detailed field and Anisotropy of Magnetic Susceptibiliy (AMS) fabric studies are presented. This work is complemented by geological mapping that focuses on fault dynamics and contact relationships. Interpretation of AMS data is aided by rock magnetic experiment data and petrographic microstructural evaluations of representative samples. A new geological map of the the Omey Pluton demonstrates that this intrusion has a defined roof and base which are gently inclined parallel to the fold hinge of the Connemara Antiform. AMS and petrographic data show the intrusion is cross cut by NNW-SSE shear zones that extend into the country rock. These pre-date and were active during magma emplacement. It is proposed that the Omey pluton was emplaced as a discordant phacolith. Pre-existing subvertical D5 faults in the host rock were reactived during emplacement, due to regional sinistral transpression, and served as centralised ascent conduits. A central portion of the Roundstone Pluton was mapped in detail for the first time. Two facies are identified, G1 forms the majority of the pluton and coeval G2 sheets cross cut G1 at the core of the pluton. NNW-SSE D5 faults mapped in the country rock extend across the pluton. These share a geometrical relationship with the distribution of submagmatic strain in the pluton and parallel the majoity of mapped subvertical G2 dykes. These data indicate that magma ascent was controlled by NNW-SSE conduits that are inherently related to those identifed in the Omey Pluton. It is proposed that the Roundstone Pluton is a punched laccolith, the symmetry and structure of which was controlled by pre-exising host rock structures and regional sinistral transpressive stress which presided during emplacement. Field relationships show the long axis of the Carna Pluton lies parallel to mulitple NNW-SSE shear zones. These are represented on a regional scale by the Clifden-Mace Fault which cross cuts the core of this intrusion. AMS and petrographic data show concentric emplacement fabrics were tectonically overprinted as magma cooled from the magmatic state due to this faulting. It is proposed that the Clifden-Mace Fault system was active during ascent and emplacement of the magma and that pluton inflation only terminated as this controlling structure went into compression due to the onset of regional transtension. U-Pb zircon laser ablation inductively coupled mass spectrometry (LA-ICP-MS) data has been compiled from four sample sites. New geochronological data from the Roundstone Pluton (RD1 = ± 3.2Ma) represent the oldest age determination obtained from any member of the GGC and demonstrates that this pluton predates the Carna Pluton by ~10Ma and probably intruded synchronously with the Omey Pluton (~422.5 ± 1.7Ma). Chronological data from the Carna Pluton (CN2 = 412.9 ± 2.5Ma; CN3 = 409.8 ± 7.2Ma; CN4 = 409.6 ± 3.6Ma) represent the first precise magma crystallisation age for this intrusion. This work shows this pluton is 10Ma older than the Kilkieran Pluton and that the supply of magma into the Carna Pluton had terminated by ~409Ma. Chronological, magnetic and field data have been utilised to evaluate the kinematic evolution of the Caledonides of western Ireland throughout the construction of the GGC. It is proposed that the GGC was constructed during four distinct episodes. The style of emplacement and the conduits used for magma transport to the site of emplacement was dependent on the orientation of local structures relative to the regional ambiant stress field. This philosophy is used to critically evaluate and progress existing hypotheses on the transition from regional transpression to regional transtension at the end of the Caledonian Orogeny.

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Existing work in Computer Science and Electronic Engineering demonstrates that Digital Signal Processing techniques can effectively identify the presence of stress in the speech signal. These techniques use datasets containing real or actual stress samples i.e. real-life stress such as 911 calls and so on. Studies that use simulated or laboratory-induced stress have been less successful and inconsistent. Pervasive, ubiquitous computing is increasingly moving towards voice-activated and voice-controlled systems and devices. Speech recognition and speaker identification algorithms will have to improve and take emotional speech into account. Modelling the influence of stress on speech and voice is of interest to researchers from many different disciplines including security, telecommunications, psychology, speech science, forensics and Human Computer Interaction (HCI). The aim of this work is to assess the impact of moderate stress on the speech signal. In order to do this, a dataset of laboratory-induced stress is required. While attempting to build this dataset it became apparent that reliably inducing measurable stress in a controlled environment, when speech is a requirement, is a challenging task. This work focuses on the use of a variety of stressors to elicit a stress response during tasks that involve speech content. Biosignal analysis (commercial Brain Computer Interfaces, eye tracking and skin resistance) is used to verify and quantify the stress response, if any. This thesis explains the basis of the author’s hypotheses on the elicitation of affectively-toned speech and presents the results of several studies carried out throughout the PhD research period. These results show that the elicitation of stress, particularly the induction of affectively-toned speech, is not a simple matter and that many modulating factors influence the stress response process. A model is proposed to reflect the author’s hypothesis on the emotional response pathways relating to the elicitation of stress with a required speech content. Finally the author provides guidelines and recommendations for future research on speech under stress. Further research paths are identified and a roadmap for future research in this area is defined.

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We have performed a retrospective analysis to evaluate the impact of age, using a 70 year cutoff, on the safety and efficacy of pegylated liposomal doxorubicin (Caelyx) given at 60 mg/m(2) every 6 weeks (treatment A) or 50 mg/m(2) every 4 weeks (treatment B) to 136 metastatic breast cancer patients in two EORTC trials, of whom 65 were 70 years of age or older. No difference in terms of toxicity was observed between younger and older patients treated with the 4-week schedule, while a higher incidence of hematological toxicity, anorexia, asthenia, and stomatitis was observed in older patients when the 6-week schedule was used. Antitumor activity was not affected by age. In the older cohort of patients, no dependence was found between the incidence of grade 3-4 toxicity or antitumor activity and patients' baseline performance status, number and severity of comorbidities, or number of concomitant medications. The higher therapeutic index of Caelyx 50 mg/m(2) every 4 weeks makes it, of the two dose schedules investigated, the preferred regimen in the elderly.

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BACKGROUND: The etiologic diagnosis of community-acquired pneumonia (CAP) remains challenging in children because blood cultures have low sensitivity. Novel approaches are needed to confirm the role of Streptococcus pneumoniae. METHODS: In this study, pneumococcal aetiology was determined by serology using a subset of blood samples collected during a prospective multicentre observational study of children <15 years of age hospitalised in Belgium with X-ray-confirmed CAP. Blood samples were collected at admission and 3-4 weeks later. Pneumococcal (P)-CAP was defined in the presence of a positive blood or pleural fluid culture. Serotyping of Streptococcus pneumoniae isolates was done with the Quellung reaction. Serological diagnosis was assessed for nine serotypes using World Health Organization validated IgG and IgA serotype-specific enzyme-linked immunosorbent assays (ELISAs). RESULTS: Paired admission/convalescent sera from 163 children were evaluated by ELISA (35 with proven P-CAP and 128 with non proven P-CAP). ELISA detected pneumococci in 82.8% of patients with proven P-CAP. The serotypes identified were the same as with the Quellung reaction in 82% and 59% of cases by IgG ELISA and IgA ELISA, respectively. Overall, ELISA identified a pneumococcal aetiology in 55% of patients with non-proven P-CAP. Serotypes 1 (51.6%), 7F (19%), and 5 (15.7%) were the most frequent according to IgG ELISA. CONCLUSIONS: In conclusion, the serological assay allows recognition of pneumococcal origin in 55% of CAP patients with negative culture. This assay should improve the diagnosis of P-CAP in children and could be a useful tool for future epidemiological studies on childhood CAP etiology.

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Measurement of antigen-specific T cell responses is an adjunctive parameter to evaluate protection induced by a previous Bordetella pertussis infection or vaccination. The assessment of T cell responses is technically complex and usually performed on fresh peripheral blood mononuclear cells (PBMC). The objective of this study was to identify simplified methods to assess pertussis specific T cell responses and verify if these assays could be performed using frozen/thawed (frozen) PBMC. Three read-outs to measure proliferation were compared: the fluorescent dye 5,6-carboxylfluorescein diacetate succinimidyl ester (CFSE) dilution test, the number of blast cells defined by physical parameters, and the incorporation of (3)H-thymidine. The results of pertussis-specific assays performed on fresh PBMC were compared to the results on frozen PBMC from the same donor. High concordance was obtained when the results of CFSE and blast read-outs were compared, an encouraging result since blast analysis allows the identification of proliferating cells and does not require any use of radioactive tracer as well as any staining. The results obtained using fresh and frozen PBMC from the same donor in the different T cell assays, including IFNγ and TNFα cytokine production, did not show significant differences, suggesting that a careful cryopreservation process of PBMC would not significantly influence T cell response evaluation. Adopting blast analysis and frozen PBMC, the possibility to test T cell responses is simplified and might be applied in population studies, providing for new instruments to better define correlates of protection still elusive in pertussis.

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Considerable scientific and intervention attention has been paid to judgment and decision-making systems associated with aggressive behavior in youth. However, most empirical studies have investigated social-cognitive correlates of stable child and adolescent aggressiveness, and less is known about real-time decision making to engage in aggressive behavior. A model of real-time decision making must incorporate both impulsive actions and rational thought. The present paper advances a process model (response evaluation and decision; RED) of real-time behavioral judgments and decision making in aggressive youths with mathematic representations that may be used to quantify response strength. These components are a heuristic to describe decision making, though it is doubtful that individuals always mentally complete these steps. RED represents an organization of social-cognitive operations believed to be active during the response decision step of social information processing. The model posits that RED processes can be circumvented through impulsive responding. This article provides a description and integration of thoughtful, rational decision making and nonrational impulsivity in aggressive behavioral interactions.

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The foraging activity of many organisms reveal strategic movement patterns, showing efficient use of spatially distributed resources. The underlying mechanisms behind these movement patterns, such as the use of spatial memory, are topics of considerable debate. To augment existing evidence of spatial memory use in primates, we generated movement patterns from simulated primate agents with simple sensory and behavioral capabilities. We developed agents representing various hypotheses of memory use, and compared the movement patterns of simulated groups to those of an observed group of red colobus monkeys (Procolobus rufomitratus), testing for: the effects of memory type (Euclidian or landmark based), amount of memory retention, and the effects of social rules in making foraging choices at the scale of the group (independent or leader led). Our results indicate that red colobus movement patterns fit best with simulated groups that have landmark based memory and a follow the leader foraging strategy. Comparisons between simulated agents revealed that social rules had the greatest impact on a group's step length, whereas the type of memory had the highest impact on a group's path tortuosity and cohesion. Using simulation studies as experimental trials to test theories of spatial memory use allows the development of insight into the behavioral mechanisms behind animal movement, developing case-specific results, as well as general results informing how changes to perception and behavior influence movement patterns.

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BACKGROUND: Given the potential importance of epithelial plasticity (EP) to cancer metastasis, we sought to investigate biomarkers related to EP in men with localized prostate cancer (PC) for the association with time to PSA recurrence and other clinical outcomes after surgery. METHODS: Men with localized PC treated with radical prostatectomy at the Durham VA Medical Center and whose prostatectomy tissues were included in a tissue microarray (TMA) linked to long-term outcomes. We performed immunohistochemical studies using validated antibodies against E-cadherin and Ki-67 and mesenchymal biomarkers including N-cadherin, vimentin, SNAIL, ZEB1 and TWIST. Association studies were conducted for each biomarker with baseline clinical/pathologic characteristics an risk of PSA recurrence over time. RESULTS: Two hundred and five men contributed TMA tissue and had long-term follow-up (median 11 years). Forty-three percent had PSA recurrence; three died of PC. The majority had high E-cadherin expression (86%); 14% had low/absent E-cadherin expression. N-cadherin was rarely expressed (<4%) and we were unable to identify an E-to-N-cadherin switch as independently prognostic. No associations with clinical risk group, PSA recurrence or Gleason sum were noted for SNAIL, ZEB1, vimentin or TWIST, despite heterogeneous expression between patients. We observed an association of higher Ki-67 expression with Gleason sum (P=0.043), National Comprehensive Cancer Network risk (P=0.013) and PSA recurrence (hazard ratio 1.07, P=0.016). CONCLUSIONS: The expression of EP biomarkers in this cohort of men with a low risk of PC-specific mortality was not associated with aggressive features or PSA relapse after surgery.

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INTRODUCTION: Malignant gliomas frequently harbor mutations in the isocitrate dehydrogenase 1 (IDH1) gene. Studies suggest that IDH mutation contributes to tumor pathogenesis through mechanisms that are mediated by the neomorphic metabolite of the mutant IDH1 enzyme, 2-hydroxyglutarate (2-HG). The aim of this work was to synthesize and evaluate radiolabeled compounds that bind to the mutant IDH1 enzyme with the goal of enabling noninvasive imaging of mutant IDH1 expression in gliomas by positron emission tomography (PET). METHODS: A small library of nonradioactive analogs were designed and synthesized based on the chemical structure of reported butyl-phenyl sulfonamide inhibitors of mutant IDH1. Enzyme inhibition assays were conducted using purified mutant IDH1 enzyme, IDH1-R132H, to determine the IC50 and the maximal inhibitory efficiency of the synthesized compounds. Selected compounds, 1 and 4, were labeled with radioiodine ((125)I) and/or (18)F using bromo- and phenol precursors, respectively. In vivo behavior of the labeled inhibitors was studied by conducting tissue distribution studies with [(125)I]1 in normal mice. Cell uptake studies were conducted using an isogenic astrocytoma cell line that carried a native IDH1-R132H mutation to evaluate the potential uptake of the labeled inhibitors in IDH1-mutated tumor cells. RESULTS: Enzyme inhibition assays showed good inhibitory potency for compounds that have iodine or a fluoroethoxy substituent at the ortho position of the phenyl ring in compounds 1 and 4 with IC50 values of 1.7 μM and 2.3 μM, respectively. Compounds 1 and 4 inhibited mutant IDH1 activity and decreased the production of 2-HG in an IDH1-mutated astrocytoma cell line. Radiolabeling of 1 and 4 was achieved with an average radiochemical yield of 56.6 ± 20.1% for [(125)I]1 (n = 4) and 67.5 ± 6.6% for [(18)F]4 (n = 3). [(125)I]1 exhibited favorable biodistribution characteristics in normal mice, with rapid clearance from the blood and elimination via the hepatobiliary system by 4 h after injection. The uptake of [(125)I]1 in tumor cells positive for IDH1-R132H was significantly higher compared to isogenic WT-IDH1 controls, with a maximal uptake ratio of 1.67 at 3 h post injection. Co-incubation of the labeled inhibitors with the corresponding nonradioactive analogs, and decreasing the normal concentrations of FBS (10%) in the incubation media substantially increased the uptake of the labeled inhibitors in both the IDH1-mutant and WT-IDH1 tumor cell lines, suggesting significant non-specific binding of the synthesized labeled butyl-phenyl sulfonamide inhibitors. CONCLUSIONS: These data demonstrate the feasibility of developing radiolabeled probes for the mutant IDH1 enzyme based on enzyme inhibitors. Further optimization of the labeled inhibitors by modifying the chemical structure to decrease the lipophilicity and to increase potency may yield compounds with improved characteristics as probes for imaging mutant IDH1 expression in tumors.