100 results on '"Crowley, H."'
Search Results
2. Seismic fragility of Italian RC precast industrial structures
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Casotto, C., Silva, V., Crowley, H., Nascimbene, R., and Pinho, R.
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- 2015
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3. Extending displacement-based earthquake loss assessment (DBELA) for the computation of fragility curves
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Silva, V., Crowley, H., Pinho, R., and Varum, H.
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- 2013
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4. Exploring the impact of spatial correlations and uncertainties for portfolio analysis in probabilistic seismic loss estimation
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Weatherill, G. A., Silva, V., Crowley, H., and Bazzurro, P.
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- 2015
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5. The potential use of chilling to control the growth of Enterobacteriaceae on porcine carcasses and the incidence of E. coli O157:H7 in pigs
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Lenahan, M., Crowley, H., OʼBrien, S. B., Byrne, C., Sweeney, T., and Sheridan, J. J.
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- 2009
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6. A prospective comparison of pedal ergometry with conventional treadmill testing in the investigation of lower extremity pain
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Manning, B. J., McGreal, G., Crowley, H., Redmond, H. P., and O’Donnell, J. A.
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- 2001
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7. Prospective comparison of conventional treadmill testing with pedal ergometry in patients with suspected claudication
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Manning, B. J., McGreal, G., Crowley, H., Redmond, H. P., and O'Donnell, J. A.
- Published
- 2000
8. Evaluation of analytical methodologies used to derive vulnerability functions.
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Silva, V., Crowley, H., Varum, H., Pinho, R., and Sousa, R.
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EARTHQUAKE hazard analysis ,STRUCTURAL frame models ,EFFECT of earthquakes on buildings ,PSYCHOLOGICAL vulnerability ,RISK assessment - Abstract
SUMMARY The recognition of fragility and vulnerability functions as a fundamental tool in seismic risk assessment has led to the development of more and more complex and elaborate procedures for their computation. Although these functions have been traditionally produced using observed damage and loss data, more recent studies propose the employment of analytical methodologies as a way to overcome the frequent lack of post-earthquake data. The variation of the structural modelling approach on the estimation of building capacity has been the target of many studies in the past; however, its influence on the resulting vulnerability model for classes of buildings, the impact in loss estimations or propagation of the uncertainty to the seismic risk calculations has so far been the object of limited scrutiny. In this paper, an extensive study of static and dynamic procedures for estimating the nonlinear response of buildings has been carried out to evaluate the impact of the chosen methodology on the resulting capacity, fragility, vulnerability and risk outputs. Moreover, the computational effort and numerical stability provided by each approach have been evaluated and conclusions drawn regarding the optimal balance between accuracy and complexity. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
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- 2014
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9. Rights, sexuality and relationships in Ireland: 'It'd be nice to be kind of trusted'.
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Kelly G, Crowley H, and Hamilton C
- Abstract
How to translate the right of people with intellectual disabilities to a full sexual and intimate life into proactive support remains a challenge for disabilities services in Ireland. Little formal research has been undertaken in this country into what people with intellectual disabilities think about these issues and what they would like to see happen in this area of their lives. This paper presents a preliminary analysis of the first author's PhD research into the views and experiences of a small group of Irish people with intellectual disabilities in the area of sexuality and relationships. Initial findings suggest that people with intellectual disabilities are getting insufficient sex education and that changes are needed at a disabilities service level to ensure that people with intellectual disabilities can express their sexuality in an open and supportive climate. At a government level, changes will need to be made to Irish legislation concerning the sexuality of vulnerable adults so that this country is meeting its obligations under the UN Convention on the Rights of Persons with Disabilities (2006). The authors argue that people with intellectual disabilities' views must come first in all debates concerning their sexuality. [ABSTRACT FROM AUTHOR]
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- 2009
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10. Displacement-Based Earthquake Loss Assessment for an Earthquake Scenario in Istanbul.
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Bal, I. E., Crowley, H., and Pinho, R.
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EARTHQUAKES , *NATURAL disasters , *SEISMOLOGY - Abstract
DBELA is a Displacement-Based Earthquake Loss Assessment methodology for urban areas which relates the displacement capacity of the building stock to the displacement demand from earthquake scenarios. The building stock is modeled as a random population of building classes with varying geometrical and material properties. The period of vibration of each building in the random population is calculated using a simplified equation based on the height of the building and building type, while the displacement capacity at different limit states is predicted using simple equations which are a function of the randomly simulated geometrical and material properties. The displacement capacity of each building is then compared to the displacement demand obtained from an over-damped displacement spectrum, using its period of vibration; the proportion of buildings where damage exceeds each specified threshold value can thus be estimated. DBELA has been applied using the Turkish building stock following the collection of a large database of structural characteristics of buildings from the northern Marmara region. The probabilistic distributions for each of the structural characteristics (e.g., story height, steel properties, etc.) have been defined using the aforementioned database. The methodology has then been applied to predict preliminary damage distributions and social losses for the Istanbul Metropolitan Municipality for a Mw 7.5 scenario earthquake. [ABSTRACT FROM AUTHOR]
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- 2008
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11. Comparison of Two Mechanics-Based Methods for Simplified Structural Analysis in Vulnerability Assessment.
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Crowley, H., Borzi, B., Pinho, R., Colombi, M., and Onida, M.
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STRUCTURAL analysis (Engineering) ,CONSTRUCTION ,STRUCTURAL engineering ,ARCHITECTURE ,INFLUENCE surfaces ,STRUCTURAL frame models ,FINITE element method ,NUMERICAL analysis ,STRUCTURAL dynamics - Abstract
Analytical vulnerability assessment methods should ideally be validated or verified by comparing their damage predictions with actual observed damage data. However, there are a number of difficulties related to the comparison of analytical damage predictions with observed damage; for example, there are large uncertainties related to the prediction of the ground motions to which the damaged buildings have been subjected. Until such problems can be resolved, it is worthwhile considering themechanics of simplified analytical vulnerability assessment methods and validating this part of the methodology through comparisons with detailed structural models. This paper looks at twomechanics-based vulnerability assessmentmethods (DBELA and SP-BELA) and compares the nonlinear static response predicted with these methods with finite elements-based nonlinear analyses of prototype buildings. A comparison of the predicted response of urban populations of buildings using the two methods is then carried out, and the influence of these differences on vulnerability curves is studied. [ABSTRACT FROM AUTHOR]
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- 2008
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12. A Comparative Study of European Earthquake Loss Estimation Tools for a Scenario in Istanbul.
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Strasser, F. O., Bommer, J. J., Şeşetyan, K., Erdik, M., Çağnan, Z., Irizarry, J., Goula, X., Lucantoni, A., Sabetta, F., Bal, I. E., Crowley, H., and Lindholm, C.
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EARTHQUAKES ,EFFECT of earthquakes on buildings ,EARTH movements - Abstract
A damage estimation exercise has been carried out using the building stock inventory and population database of the Istanbul Metropolitan Municipality and selected European earthquake loss estimation packages: KOERILOSS, SELENA, ESCENARIS, SIGE, and DBELA. The input ground-motions, common to all models, correspond to a “credible worst case scenario” involving the rupture of the four segments of the Main Marmara Fault closest to Istanbul in a Mw 7.5 earthquake. The aim of the exercise is to assess the applicability of the selected software packages to earthquake loss estimation in the context of rapid post-earthquake response in European urban centers. The results in terms of predicted building damage and social losses are critically compared amongst each other, as well as with the results of previous scenario-based earthquake loss assessments carried out for the study area. The key methodological aspects and data needs for European rapid post-earthquake loss estimation are thus identified. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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13. Preliminary Study on the Impact of the Introduction of an Updated Seismic Hazard Model for Italy.
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Gavridou, S., Pinho, R., Crowley, H., Calvi, G. M., Montaldo, V., Meletti, C., and Stucchi, M.
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EARTHQUAKE resistant design ,EARTHQUAKE engineering ,CITIES & towns ,EARTHQUAKE hazard analysis - Abstract
A new hazard model for Italy has recently been proposed; hazard maps have been produced for various return periods, allowing the values of peak ground acceleration (PGA) and spectral accelerations for response periods up to 2 s to be interpolated for each of the 8,101 Italian municipalities. The new model allows for a more refined definition of the hazard in each municipality as compared to the current use of a fixed spectral shape anchored to upper bound 475-year PGA values and scaling factors for different return periods. The aim of this work is to investigate, in a preliminary fashion, the implications that the adoption of the new return-period dependent hazard maps would have on design and assessment of structures. To this end, the seismic performance of reinforced concrete frames of varying height is evaluated assuming they were located in each of the 8,101 municipalities in Italy and the results obtained with the current and the new hazard model are compared. The new model is shown to result in lower seismic risk in the majority of the municipalities. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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14. Enterobacteriaceae in beef products from retail outlets in the Republic of Ireland and comparison of the presence and counts of E. coli O157:H7 in these products
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Crowley, H., Cagney, C., Sheridan, J.J., Anderson, W., McDowell, D.A., Blair, I.S., Bishop, R.H., and Duffy, G.
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ENTEROBACTERIACEAE , *ESCHERICHIA coli , *SUPERMARKETS , *BEEF , *GRAM-negative bacteria - Abstract
Abstract: This study investigated the prevalence and numbers of Enterobacteriaceae in minced beef and beef burgers purchased from supermarkets and butcher shops in the Republic of Ireland (RoI). Samples (n=1303) collected between June 2001 and April 2002 from every county in the RoI (∼60 per county) were examined for the presence of Enterobacteriaceae using method BS 5763. Overall, in the 43 beef products in which E. coli O157:H7 was present the Enterobacteriaceae counts ranged from 0.52 to 6.98log10 cfug−1. There was no correlation between the number of Enterobacteriaceae and the presence of E. coli O157:H7. There were no significant differences between Enterobacteriaceae numbers in fresh, unpackaged, minced beef samples from butcher shops and supermarkets, or in fresh, unpackaged, beef burgers from butcher shops and supermarkets. However, there were significant differences among the numbers of Enterobacteriaceae detected in different minced beef products. The numbers of Enterobacteriaceae in fresh, unpackaged, minced beef (6.54–6.98log10 cfug−1) were considerably higher than in preprepared or prepackaged minced beef (2.95–3.62log10 cfug−1). [Copyright &y& Elsevier]
- Published
- 2005
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15. PERIOD-HEIGHT RELATIONSHIP FOR EXISTING EUROPEAN REINFORCED CONCRETE BUILDINGS.
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CROWLEY, H. and PINHO, R.
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REINFORCED concrete construction , *CONSTRUCTION materials , *REINFORCED concrete buildings , *EIGENVALUES , *HILL determinant , *EARTHQUAKE engineering - Abstract
Simple empirical relationships are available in many design codes to relate the height of a building to its fundamental period of vibration. These relationships have been realised for force-based design and so produce conservative estimates of period such that the lateral shear force will be conservatively predicted from an acceleration spectrum. Where assessment of a structure is concerned, however, it is the displacement demand that gives an indication of the damage that can be expected; this displacement would be underestimated with the use of the aforementioned period-height formulae. Furthermore, the period of vibration of interest in assessment is the yield period, which is calculated using the yield stiffness, also often referred to as the cracked or elastic stiffness. The derivation of a yield period-height formula for use in displacement-based assessment of European buildings is thus the focus of this work. Analytical fibre element models of RC frames of varying height have been developed and the yield period has been sought using eigenvalue, pushover and dynamic analyses. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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16. Prevalence and numbers of Escherichia coli O157:H7 in minced beef and beef burgers from butcher shops and supermarkets in the Republic of Ireland
- Author
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Cagney, C., Crowley, H., Duffy, G., Sheridan, J.J., O’Brien, S., Carney, E., Anderson, W., McDowell, D.A., Blair, I.S., and Bishop, R.H.
- Subjects
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ESCHERICHIA coli , *BEEF , *GENES - Abstract
This study investigated the prevalence and numbers of Escherichia coli O157:H7 in minced beef and beef burgers in supermarkets and butcher shops in the Republic of Ireland. Fifteen samples were collected quarterly from each of 26 counties over a 13-month period. All samples (n=1533) were (1) directly plated on SMAC, and (2) enriched in mTSB with novobiocin, extracted by immunomagnetic separation (IMS), plating onto SMAC-CT agar and finally confirmed by PCR. Overall, E. coli O157:H7 was recovered from 43 samples (2.80%) with counts ranging from <0.52–4.03 log10 cfu g−1. Of the positive samples, 2.70% (32/1183) were purchased from supermarkets and 3.14% (11/350) from butcher shops. Only one product type (fresh unpacked burgers from supermarkets) was negative for E. coli O157:H7. Of the products containing the pathogen, fresh packaged burgers from supermarkets had the highest prevalence of 4.46% (7/157) while fresh unpackaged mince purchased from supermarkets had the lowest prevalence of 2.01% (6/299). Of the 43 isolates recovered, 41 possessed verotoxin-producing genes (vt1 and vt2), E. coli attaching and effacing gene (eaeA), haemolysin gene (hlyA), 60-MDa plasmid or rfb gene cluster that encodes for the biosynthesis of the O-antigen (pO157) and flagellar H7 antigen encoding gene (fliCh7). The remaining 2/43 isolates contained only one of the verotoxin-producing genes (vt1 or vt2) and all the other genes named. [Copyright &y& Elsevier]
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- 2004
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17. Development Engineering on System 465L.
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Riley, D. E., Hanscom, L. G., Strom, C. A., Crowley, H. J., and Tagliaferri, O. A.
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- 1965
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18. DICOSE--A New Tool for Communications Studies.
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Crowley, H.
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- 1967
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19. 1064. Indicine: the major alkaloid of Heliotropium indicum L.
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Mattocks, A. R., Schoental, R., Crowley, H. C., and Culvenor, C. C. J.
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- 1961
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20. Tumors of ceruminous glands.
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Cankar, V. and Crowley, H.
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- 1964
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21. A Field Test of Error Control Systems.
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Crowley, H.
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- 1969
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22. Analogs of arachidonic acid methylated at C-7 and C-10 as inhibitors of leukotriene biosynthesis
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Cohen, N., Weber, G., Banner, B.L., Welton, A.F., Hope, W.C., Crowley, H., Anderson, W.A., Simko, B.A., O'Donnell, M., Coffey, J.W., Fiedler-Nagy, C., and Batula-Bernardo, C.
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- 1984
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23. Changes in milk composition during lactation in the potoroo, Potorous tridactylus (Marsupialia: Potoroinae)
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Rose, R. W., Crowley, H. M., and Woodward, D. R.
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- 1988
24. ChemInform Abstract: Dehydration of Formamides Using the Burgess Reagent: A New Route to Isocyanides.
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CREEDON, S. M., CROWLEY, H. K., and MCCARTHY, D. G.
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- 1998
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25. ChemInform Abstract: Thienotriazolodiazepines as Platelet-Activating Factor Antagonists. Steric Limitations for the Substituent in Position 2.
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WALSER, A., FLYNN, T., MASON, C., CROWLEY, H., MARESCA, C., and O'DONNELL, M.
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- 1991
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26. ChemInform Abstract: Triazolobenzo- and Triazolothienodiazepines as Potent Antagonists of Platelet Activating Factor.
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WALSER, A., FLYNN, T., MASON, C., CROWLEY, H., MARESCA, C., YAREMKO, B., and O'DONNELL, M.
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- 1991
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27. ChemInform Abstract: N-(Heterocyclic alkyl)pyrido(2,1-b)quinazoline-8-carboxamides as Orally Active Antiallergy Agents.
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TILLEY, J. W., LEVITAN, P., LIND, J., WELTON, A. F., CROWLEY, H. J., TOBIAS, L. D., and O'DONNELL, M.
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- 1987
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28. ChemInform Abstract: Substituted (Aryloxy)alkanoic Acids as Antagonists of Slow-Reacting Substance of Anaphylaxis.
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LEMAHIEU, R. A., CARSON, M., HAN, R.-J., NASON, W. C., O'DONNELL, M., BROWN, D. L., CROWLEY, H. J., and WELTON, A. F.
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- 1987
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29. Dehydration of formamides using the Burgess Reagent: a new route to isocyanides.
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M. Creedon, Siobhan, Kevin Crowley, H., and G. McCarthy, Daniel
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- 1998
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30. 143 Comparative mechanism of action of Ro 22-3747 (trans-3-[6-(methylthio)-4-oxo-4H-quinazolin-3-yl]-2-propenoic acid), oxatomide, and ketotifen
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Welton, A.F., Hope, W., Crowley, H., and Yaremko, B.
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- 1983
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31. Twice daily allied health rehabilitation is feasible in acutely hospitalised older people: an observational study.
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Kay JE, D'Souza AN, Klaic M, Jacob AN, Marston C, Goonan R, Crowley H, and Granger CL
- Abstract
ObjectiveTo evaluate the feasibility of twice daily rehabilitation in older patients admitted to an acute care of the elderly (ACE) hospital ward.MethodThis was a prospective single-site, cohort study of twice daily interventions provided by ACE physiotherapists, occupational therapists and/or allied health assistants in an ACE hospital ward. The feasibility of twice daily therapy was evaluated using a range of outcomes including satisfaction, fidelity and limited efficacy.ResultsA total of 220 patients were included (median age 86 [IQR 81-91]years, 54% female, with a median length of hospital stay of 7 [IQR 5-10] days). Twice daily therapy was delivered on 71% (n=757) of patient admitted weekdays (fidelity). Moderate-to-large effect sizes were observed in patient functional and mobility measures during their hospital stay and most patients (74%) were able to be successfully discharged home (limited efficacy). Both staff and patients reported high levels of satisfaction with physiotherapy and occupational therapy while on the ACE ward.ConclusionTwice daily therapy with acutely hospitalised elderly patients is feasible, facilitated discharge home, and is associated with high patient and staff satisfaction.
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- 2024
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32. Influence of methodological and patient factors on serum NMDAR IgG antibody detection in psychotic disorders: a meta-analysis of cross-sectional and case-control studies.
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Cullen AE, Palmer-Cooper EC, Hardwick M, Vaggers S, Crowley H, Pollak TA, and Lennox BR
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- Case-Control Studies, Cross-Sectional Studies, Humans, Psychotic Disorders blood, Immunoglobulin G immunology, Psychotic Disorders immunology, Receptors, N-Methyl-D-Aspartate blood, Receptors, N-Methyl-D-Aspartate immunology
- Abstract
Background: Antibodies targeting the N-methyl-D-aspartate receptor (NMDAR) have been detected in patients with psychosis. However, studies measuring the IgG subclass in serum have provided variable estimates of prevalence, and it is unclear whether these antibodies are more common in patients than controls. Because these inconsistencies could be due to methodological approaches and patient characteristics, we aimed to investigate the effect of these factors on heterogeneity., Methods: We searched Web of Science and Ovid (MEDLINE and PsycINFO) for cross-sectional and case-control studies published between Jan 1, 2000, and May 5, 2019, that reported NMDAR IgG antibody seropositivity in patients with psychosis. Pooled proportions and odds ratios (ORs) were derived using random-effects models. We estimated between-study variance (τ
2 ) and the proportion of observed variance due to heterogeneity (I2 ). We then used univariable random-effects meta-regression analysis to investigate the effect of study factors on heterogeneity of proportions and ORs. Our protocol was registered on PROSPERO (CRD42018099874)., Findings: Of 1276 articles in the initial search, 28 studies were eligible for inclusion, including 14 cross-sectional studies and 14 case-control studies. In cross-sectional studies, NMDAR IgG antibodies were detected in 0·73% (95% CI 0·09-1·38; I2 56%; p=0·026) of patients with psychosis, and in case-control studies, patients with psychosis were not significantly more likely to be seropositive than healthy individuals (OR 1·57, 95% CI 0·78-3·16; I2 15%; p=0·20). Meta-regression analyses indicated that heterogeneity was significantly associated with assay type across both study designs, illness stage in cross-sectional studies, and study quality in case-control studies. Compared with studies using a fixed cell-based assay, cross-sectional and case-control studies using the live method yielded higher pooled prevalence estimates (0·36% [95% CI -0·23 to 0·95] vs 2·97% [0·70 to 5·25]) and higher ORs (0·65 [0·33 to 1·29] vs 4·43 [1·73 to 11·36]). In cross-sectional studies, the prevalence was higher in exclusively first-episode samples than in multi-episode or mixed samples (2·18% [0·25 to 4·12] vs 0·16% [-0·31 to 0·63]), and in case-control studies, higher ORs were reported in low-quality studies than in high-quality studies (3·80 [1·47 to 9·83] vs 0·72 [0·36 to 1·42])., Interpretation: Higher estimates of NMDAR IgG antibody prevalence have been obtained with the live cell-based assay, and studies using this method find that seropositivity is more common in patients with psychosis than in controls. The effects of illness stage and study quality on heterogeneity were not consistent across study designs, and we provide clear recommendations for clinicians and researchers regarding interpreting these findings., Funding: None., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2021
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33. Diagnostic limitations and considerations in the imaging evaluation of advanced multicentric infantile myofibromatosis.
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Parikh A, Driscoll CAH, Crowley H, York T, Dachy G, Demoulin JB, and Hoffman SB
- Abstract
Infantile myofibromatosis, the most common fibrous tumor of infancy, is classified in 2 forms; as a solitary nodule or as numerous, widely-distributed multicentric lesions with or without visceral involvement. Although benign, multicentric myofibromas are still associated with a high incidence of morbidity and mortality due to the infiltration of critical structures. Herein, we present a case of an infant with aggressive PDGFRB and NOTCH3 mutation-negative myofibromas distributed throughout the vascular, respiratory, and gastrointestinal systems. The extensive disease resulted in pulmonary hypertension, respiratory failure and gastrointestinal obstruction refractory to chemotherapy and unamenable to surgical resection. Despite the presence of numerous highly invasive myofibromas, multiple imaging modalities largely underestimated, or even missed, tumors found at autopsy. This case demonstrates the limitations of radiographic imaging to assess disease burden in multicentric infantile myofibromatosis. The postmortem findings of extensive disease far exceeding what was demonstrated by multiple imaging modalities suggests that pediatricians should have a high index of suspicion for undetected tumors if clinical deterioration is otherwise unexplained., (© 2020 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)
- Published
- 2020
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34. Clinician's Commentary on Bessette et al.
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Crowley H
- Published
- 2020
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35. Serum neuronal cell-surface antibodies in first-episode psychosis-Authors' reply.
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Lennox BR, Pollak T, Palmer-Cooper EC, Scoriels L, Harrison PJ, Jones PB, Lang B, Crowley H, Marks J, and Vincent A
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- Humans, Psychotic Disorders blood
- Published
- 2017
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36. Research priorities for managing the impacts and dependencies of business upon food, energy, water and the environment.
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Green JMH, Cranston GR, Sutherland WJ, Tranter HR, Bell SJ, Benton TG, Blixt E, Bowe C, Broadley S, Brown A, Brown C, Burns N, Butler D, Collins H, Crowley H, DeKoszmovszky J, Firbank LG, Fulford B, Gardner TA, Hails RS, Halvorson S, Jack M, Kerrison B, Koh LSC, Lang SC, McKenzie EJ, Monsivais P, O'Riordan T, Osborn J, Oswald S, Price Thomas E, Raffaelli D, Reyers B, Srai JS, Strassburg BBN, Webster D, Welters R, Whiteman G, Wilsdon J, and Vira B
- Abstract
Delivering access to sufficient food, energy and water resources to ensure human wellbeing is a major concern for governments worldwide. However, it is crucial to account for the 'nexus' of interactions between these natural resources and the consequent implications for human wellbeing. The private sector has a critical role in driving positive change towards more sustainable nexus management and could reap considerable benefits from collaboration with researchers to devise solutions to some of the foremost sustainability challenges of today. Yet opportunities are missed because the private sector is rarely involved in the formulation of deliverable research priorities. We convened senior research scientists and influential business leaders to collaboratively identify the top forty questions that, if answered, would best help companies understand and manage their food-energy-water-environment nexus dependencies and impacts. Codification of the top order nexus themes highlighted research priorities around development of pragmatic yet credible tools that allow businesses to incorporate nexus interactions into their decision-making; demonstration of the business case for more sustainable nexus management; identification of the most effective levers for behaviour change; and understanding incentives or circumstances that allow individuals and businesses to take a leadership stance. Greater investment in the complex but productive relations between the private sector and research community will create deeper and more meaningful collaboration and cooperation., Competing Interests: Compliance with ethical standardsThis exercise was explicitly devised to take into account the interests of scientists, businesses and civil society. Those who took part in the prioritisation process (voting and workshop stages) are all listed as co-authors in this study except Monica Contestabile (Nature Publishing Group). Whilst the individuals who participated represented their own opinions, please note in the author details the companies and organisations whose employees have helped to shape and prioritise these research questions.
- Published
- 2017
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37. Prevalence and clinical characteristics of serum neuronal cell surface antibodies in first-episode psychosis: a case-control study.
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Lennox BR, Palmer-Cooper EC, Pollak T, Hainsworth J, Marks J, Jacobson L, Lang B, Fox H, Ferry B, Scoriels L, Crowley H, Jones PB, Harrison PJ, and Vincent A
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- Adolescent, Adult, Case-Control Studies, Female, Humans, Male, Prevalence, Psychotic Disorders therapy, Young Adult, Antibodies, Monoclonal blood, Antigens, Surface blood, Neurons immunology, Psychotic Disorders blood
- Abstract
Background: Psychosis is a common presenting feature in antibody-mediated encephalitis, for which prompt recognition and treatment usually leads to remission. We aimed to investigate whether people with circumscribed schizophrenia-like illnesses have such antibodies-especially antibodies against the N-methyl-D-aspartate receptor (NMDAR)-more commonly than do healthy controls., Methods: We recruited patients aged 14-35 years presenting to any of 35 mental health services sites across England with first-episode psychosis, less than 6 weeks of treatment with antipsychotic medication, and a score of 4 or more on at least one selected Positive and Negative Syndrome Scale (PANSS) item. Patients and controls provided venous blood samples. We completed standardised symptom rating scales (PANSS, ACE-III, GAF) at baseline, and tested serum samples for antibodies against NMDAR, LGI1, CASPR2, the GABA
A receptor, and the AMPA receptor using live cell-based assays. Treating clinicians assessed outcomes of ICD diagnosis and functioning (GAF) at 6 months. We included healthy controls from the general population, recruited as part of another study in Cambridge, UK., Findings: Between Feb 1, 2013, and Aug 31, 2014, we enrolled 228 patients with first-episode psychosis and 105 healthy controls. 20 (9%) of 228 patients had serum antibodies against one or more of the neuronal cell surface antibodies compared with four (4%) of 105 controls (unadjusted odds ratio 2·4, 95% CI 0·8-7·3). These associations remained non-significant when adjusted for current cigarette smoking, alcohol consumption, and illicit drug use. Seven (3%) patients had NMDAR antibodies compared with no controls (p=0·0204). The other antibodies did not differ between groups. Antibody-positive patients had lower PANSS positive, PANSS total, and catatonia scores than did antibody-negative patients. Patients had comparable scores on other PANSS items, ACE-III, and GAF at baseline, with no difference in outcomes at 6 months., Interpretation: Some patients with first-episode psychosis had antibodies against NMDAR that might be relevant to their illness, but did not differ from patients without NMDAR antibodies in clinical characteristics. Our study suggests that the only way to detect patients with these potentially pathogenic antibodies is to screen all patients with first-episode psychosis at first presentation., Funding: Medical Research Council., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
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38. Mobilizing Reconciliation: Implications of the Truth and Reconciliation Commission Report for Physiotherapy in Canada.
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Gasparelli K, Crowley H, Fricke M, McKenzie B, Oosman S, and Nixon SA
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- 2016
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39. A risk-mitigation approach to the management of induced seismicity.
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Bommer JJ, Crowley H, and Pinho R
- Abstract
Earthquakes may be induced by a wide range of anthropogenic activities such as mining, fluid injection and extraction, and hydraulic fracturing. In recent years, the increased occurrence of induced seismicity and the impact of some of these earthquakes on the built environment have heightened both public concern and regulatory scrutiny, motivating the need for a framework for the management of induced seismicity. Efforts to develop systems to enable control of seismicity have not yet resulted in solutions that can be applied with confidence in most cases. The more rational approach proposed herein is based on applying the same risk quantification and mitigation measures that are applied to the hazard from natural seismicity. This framework allows informed decision-making regarding the conduct of anthropogenic activities that may cause earthquakes. The consequent risk, if related to non-structural damage (when re-location is not an option), can be addressed by appropriate financial compensation. If the risk poses a threat to life and limb, then it may be reduced through the application of strengthening measures in the built environment-the cost of which can be balanced against the economic benefits of the activity in question-rather than attempting to ensure that some threshold on earthquake magnitude or ground-shaking amplitude is not exceeded. However, because of the specific characteristics of induced earthquakes-which may occur in regions with little or no natural seismicity-the procedures used in standard earthquake engineering need adaptation and modification for application to induced seismicity.
- Published
- 2015
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40. The MHC class I-related FcRn ameliorates murine Lyme arthritis.
- Author
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Crowley H, Alroy J, Sproule TJ, Roopenian D, and Huber BT
- Subjects
- Animals, Ankle pathology, Edema, Histocompatibility Antigens Class I, Mice, Mice, Inbred C3H, Mice, Inbred C57BL, Myocardium pathology, Tarsal Joints pathology, Antibodies, Bacterial immunology, Borrelia burgdorferi immunology, Immunoglobulin G immunology, Lyme Disease immunology, Lyme Disease microbiology, Receptors, Fc immunology
- Abstract
The identification of the neonatal FcR (FcRn) as an IgG homeostasis regulator has led to research aimed at delineating a role for FcRn in humorally mediated disease. FcRn is a class I-related molecule that prolongs the half-life of serum IgG by preferentially binding IgG at low pH and inhibiting its degradation. Its role in protective immunity to infectious organisms is unknown. We investigated the function of FcRn in the murine model of Lyme arthritis, caused by infection with Borrelia burgdorferi. We infected FcRn(-/-) and wild-type mice with B. burgdorferi and monitored the development of arthritis. Infected FcRn(-/-) mice demonstrated decreased serum levels of anti-B. burgdorferi antibodies and borreliacidal activity. Moreover, these mutant mice developed increased ankle swelling and joint histopathology following infection. Our data suggest that FcRn ameliorates murine Lyme arthritis by preventing the degradation of protective borreliacidal antibodies.
- Published
- 2006
- Full Text
- View/download PDF
41. Host-adapted Borrelia burgdorferi in mice expresses OspA during inflammation.
- Author
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Crowley H and Huber BT
- Subjects
- Adaptation, Physiological, Animals, Antigens, Surface analysis, Bacterial Outer Membrane Proteins analysis, Bacterial Vaccines, Cell Count, Cytokines biosynthesis, Female, Flow Cytometry, Mice, Peritonitis microbiology, Transcription, Genetic, Zymosan pharmacology, Antigens, Surface genetics, Bacterial Outer Membrane Proteins genetics, Borrelia burgdorferi metabolism, Gene Expression Regulation, Bacterial, Lipoproteins
- Abstract
Antibody responses to outer surface protein A (OspA) of Borrelia burgdorferi may occur during periods of arthritis late in the clinical course of untreated Lyme disease. These antibody responses are paradoxical, given the conclusive evidence demonstrating that B. burgdorferi transmitted to the mammalian host expresses little or no OspA. The parallel occurrence of OspA antibodies and arthritic episodes suggests that OspA expression is upregulated during infection with B. burgdorferi. We hypothesized that this was due to the inflammatory environment caused by the immune response to the spirochete. To test our hypothesis, we adapted an in vivo model that mimics the host-pathogen interaction. Dialysis chambers containing B. burgdorferi were implanted into the peritoneal cavities of mice in the presence or absence of zymosan, a yeast cell wall extract that induces inflammation. Spirochetes were harvested 2 days later, and OspA expression was assessed at the protein and transcription level by Western blotting and real-time reverse transcription-PCR, respectively. Flow cytometry was also utilized to evaluate OspA protein expression on individual spirochetes. B. burgdorferi maintained in an inflammatory in vivo environment show an increased OspA expression relative to B. burgdorferi kept under normal in vivo conditions. Furthermore, host-adapted B. burgdorferi with a low OspA phenotype upregulates OspA expression when transferred to an inflammatory in vivo environment. The results obtained by these techniques uniformly identify inflammation as a mediator of in vivo OspA expression in host-adapted B. burgdorferi, providing insights into the behavior of live spirochetes in the mammalian host.
- Published
- 2003
- Full Text
- View/download PDF
42. Steatosis in donor and transplant liver biopsies.
- Author
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Crowley H, Lewis WD, Gordon F, Jenkins R, and Khettry U
- Subjects
- Biopsy, Fatty Liver etiology, Humans, Liver pathology, Tissue Donors, Fatty Liver pathology, Liver Transplantation adverse effects
- Abstract
The purpose of this study was to identify the significance and clinical correlation of steatosis in donor and posttransplantation liver biopsies. One hundred twenty-six liver biopsies with fatty change from 86 liver transplant patients were reviewed. Micro- and macro-steatosis were graded semiquantitatively and correlated with clinical and other pathologic parameters. Fifty-one donor biopsy specimens, from 50 patients, had combinations of micro- (predominantly) and macro-steatosis. One of 2 patients with high-grade micro- and macro-steatosis required a retransplantation on the third day. Three early deaths were not related to graft dysfunction. In 36 patients, steatosis developed after transplantation. In 13 of 36, steatosis was seen in the early postoperative period with a background of severe ischemic injury, 6 of whom died within 45 days posttransplantation. Other causes of steatosis developing after liver transplantation included hepatitis C (n = 12), alcoholic steatohepatitis (n = 3), diabetes mellitus or obesity (n = 7) and poor nutrition (n = 2). The presence of steatosis in 1 patient's donor and all posttransplantation biopsy specimens remained unexplained. In conclusion, (1) microsteatosis in donor liver biopsy specimens has no effect on graft function; (2) ischemic injury with development of steatosis in the early posttransplantation period may be associated with poor clinical outcome; and (3) steatosis in the posttransplantation period is uncommon and usually related to recurrent or acquired hepatitis C.
- Published
- 2000
- Full Text
- View/download PDF
43. Ultrastructural localization of gustducin immunoreactivity in microvilli of type II taste cells in the rat.
- Author
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Yang R, Tabata S, Crowley HH, Margolskee RF, and Kinnamon JC
- Subjects
- Animals, Antibodies, Cytoplasm chemistry, Female, Fluorescent Antibody Technique, GTP-Binding Proteins physiology, Male, Microscopy, Confocal, Microscopy, Immunoelectron, Microvilli immunology, Rats, Signal Transduction physiology, Taste Buds physiology, Taste Buds ultrastructure, Transducin immunology, Microvilli chemistry, Rats, Sprague-Dawley physiology, Taste Buds chemistry, Transducin analysis
- Abstract
Gustducin is a transducin-like G protein (guanine nucleotide-binding protein) that is expressed in taste bud cells. Gustducin is believed to be involved in bitter and possibly sweet taste transduction. In the present study, we demonstrate that a subset of type II cells displays immunoreactivity to antisera directed against gustducin in taste buds of rat circumvallate papilla. Immunogold particles are present both in the microvilli and cytoplasm of the immunoreactive cells. Quantitative analysis of the data suggests that the number of colloidal gold particles (P<0.001) and nanogold particles (P<0.01) in the immunoreactive type II cells are much greater than in type I cells. There are also approximately 2.5 times (P<0.05) as many colloidal gold particles associated with the microvilli versus the cytoplasm in the immunoreactive type II cells. The ultrastructural distribution of gustducin immunoreactivity is consistent with its proposed role in the initial events of sensory transduction by gustatory receptor cells., (Copyright 2000 Wiley-Liss, Inc.)
- Published
- 2000
- Full Text
- View/download PDF
44. Taste cells with synapses in rat circumvallate papillae display SNAP-25-like immunoreactivity.
- Author
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Yang R, Crowley HH, Rock ME, and Kinnamon JC
- Subjects
- Animals, Female, Male, Neurons, Afferent metabolism, Rats, Rats, Sprague-Dawley, Synapses metabolism, Synaptosomal-Associated Protein 25, Taste Buds metabolism, Membrane Proteins, Nerve Tissue Proteins metabolism, Neurons, Afferent ultrastructure, Synapses ultrastructure, Taste Buds ultrastructure
- Abstract
SNAP-25 is a 25 kDa protein believed to be involved in the processes of membrane fusion and exocytosis associated with neurotransmitter release. In the present study we present evidence that SNAP-25-like immunoreactivity can be used as a marker for taste cells with synapses in rat circumvallate papillae. SNAP-25 immunoreactivity is present in most intragemmal nerve processes and a small subset of taste cells. Intense immunoreactivity is associated with the nerve plexus located below the base of the taste bud. Of a total of 87 taste cells with synapses onto nerve processes, 80 of the presynaptic taste cells had SNAP-25 immunoreactivity. The association of SNAP-25 immunoreactivity with taste cells possessing synapses suggests that these cells may be gustatory receptor cells. Because this SNAP-25 antibody can label taste cells with synapses, it may also serve as a useful tool for future studies correlating structure with function in the taste bud., (Copyright 2000 Wiley-Liss, Inc.)
- Published
- 2000
- Full Text
- View/download PDF
45. Cues for perception of synthetic and natural diphthongs in either noise or reverberation.
- Author
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Nábĕlek AK, Ovchinnikov A, Czyzewski Z, and Crowley HJ
- Subjects
- Adult, Aged, Hearing, Humans, Middle Aged, Time Factors, Noise, Phonetics, Speech Perception, Speech, Alaryngeal
- Abstract
The relationship between relative intensity of transition segments and identification of diphthongs has been investigated. In the first experiment, synthesized stimuli were used. The stimuli differed in the amount of attenuation of the transition segment which ranged from 0 to 15 dB. It was expected that [diphthong in text] responses would be obtained for stimuli with attenuated transitions. The stimuli were tested in quiet, noise, and reverberation with ten normal-hearing and seven hearing-impaired subjects. For the stimulus with the most attenuated transition, the normal-hearing subjects gave no [diphthong in text] responses and the hearing-impaired subjects gave only 20% [diphthong in text] responses in quiet. However, in noise, both groups of subjects gave 70% [diphthong in text] responses and in reverberation, the normal-hearing subjects gave 95% and the hearing-impaired subjects gave 90% [diphthong in text] responses. Generally, less transition attenuation was needed for the hearing-impaired than for the normal-hearing subjects to give [diphthong in text] responses. These findings indicated that identification errors in noise and reverberation for naturally produced diphthongs might be related to the intensity of their transition segments. In the second experiment, naturally produced diphthongs [diphthongs in text] from the Nábĕlek et al. [J. Acoust. Soc. Am. 92, 1228-1246 (1992)] study were spectrally analyzed. There were 30 different tokens for each diphthong. The results of the analyses indicated significant correlations between the number of identification errors for these diphthongs made by either normal-hearing or hearing-impaired subjects and the relative intensities of the F2 transition segment. In both noise and reverberation there were fewer errors for the diphthong tokens characterized by high intensity F2 transitions.
- Published
- 1996
- Full Text
- View/download PDF
46. Estimation of client-assessed hearing aid performance based upon unaided variables.
- Author
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Crowley HJ and Nabelek IV
- Subjects
- Aged, Female, Humans, Male, Middle Aged, Severity of Illness Index, Sex Factors, Speech Perception, Hearing Aids, Hearing Loss, Sensorineural rehabilitation
- Abstract
The purpose of this study was to investigate the possibility of estimating client-assessed hearing aid performance before hearing aids are purchased. Aided performance was represented by the Profile of Hearing Aid Performance (PHAP, Cox & Gilmore, 1990). Multiple regression was applied to 16 unaided predictor variables and to 8 response variables. The response variables were the scores from the seven PHAP subscales plus the overall PHAP score, which were obtained from 46 participants. Audiologic, demographic, and psychological information was included among the 16 predictor variables. The average widths of 95% prediction intervals showed that, with the exception of the Aversiveness of Sounds and Ease of Communication subscales, PHAP subscale scores were predicted within 15% on average. Eighty percent or more of the individual participants' PHAP scores were predicted within 15% for all but the Aversiveness of Sounds subscale. The predictor variables appearing in regression equations for the greatest number of PHAP subscales include age, Communication Strategies and Personal Adjustment scores from the Communication Profile for the Hearing Impaired (Demorest & Erdman, 1986), Revised Speech Perception in Noise (Bilger, Neutzel, Rabinowitz, & Rzeczkowski, 1984; Kalikow, Stevens, & Elliott, 1977) test scores, comfortable loudness levels, and the difference between National Acoustic Laboratories' target gain (Byrne & Dillon, 1986) and actual insertion gain. Further testing of the models on additional participants would be needed to determine their clinical applicability. In addition to being potentially useful for predicting client-assessed aided performance, the equations obtained in this study identify relationships between the aided and unaided variables that can be applied in the counseling of new hearing aid users.
- Published
- 1996
- Full Text
- View/download PDF
47. Problems in the recognition of aortoembolic stroke.
- Author
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Gordon DL, Crowley HM, Siouffi SY, and Skelton TN
- Abstract
Recent reports suggest aortoembolism is an important cause of stroke. Although transesophageal echocardiography visualizes the aortic arch, diagnosis of aortoembolism stroke is not common. We investigated reasons for this discrepancy at our institution. We reviewed charts and transesophageal echocardiography videotapes of 16 patients with recent ischemic stroke or transient ischemic attack who had undergone transesophageal echocardiography. For each patient, we determined the most likely cause of cerebral ischemia, and we compared the official transesophageal echocardiography report to our interpretation of the videotape. In our videotape review, 13 patients had good visualization of the aortic arch. Of 6 patients with atherosclerosis in the arch, 1 had high-grade carotid stenosis, 1 had atrial fibrillation, 1 had "small-vessel disease," and 3 had cerebral ischemia of unknown cause. The official reports did not mention aortic arch disease in 4 of 6 patients. A possible cause of cerebral ischemia was identified in 6 of 7 patients with normal aortic arches. Of 3 patients who had poor visualization of the aortic arch, one had "small-vessel disease," and 2 had ischemic stroke of unknown cause despite extensive workups. We conclude that aortic arch disease is common in patients with ischemic stroke and transient ischemic attack and may be a cause of cerebral ischemia, especially in patients with stroke or transient ischemic attack due to small-vessel occlusion or of unknown cause. Aortic arch disease may not be identified as the cause of stroke or transient ischemic attack because (a) transesophageal echocardiography is not done, (b) transesophageal echocardiography is done but the aortic arch is not visualized, (c) transesophageal echocardiography is done, the aortic arch is visualized, but the examiner does not comment on aortic arch disease, or (d) despite transesophageal echocardiography identification of arotic arch disease, the treating physician does not consider the aorta to be a potential source of embolization., (Copyright © 1995 National Stroke Association. Published by Elsevier Inc. All rights reserved.)
- Published
- 1995
- Full Text
- View/download PDF
48. Cues for perception of the diphthong /aI/ in either noise or reverberation. Part I. Duration of the transition.
- Author
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Nábĕlek AK, Czyzewski Z, and Crowley H
- Subjects
- Acoustic Stimulation, Adult, Aged, Humans, Middle Aged, Noise adverse effects, Speech Discrimination Tests, Hearing, Hearing Loss, Bilateral, Phonetics, Speech Perception
- Abstract
Location of boundaries (the 50% response point) and slopes of identification functions were determined for synthesized /a-aI/ vowel continua. Within each continuum, the stimuli contained a steady-state segment followed by a transition in which the frequencies of formants changed in time. Here, F1 changed in a downward direction and F2 changed in an upward direction. Total duration of each stimulus was 200 ms. The duration of the transition was increased in steps from 0 to 140 ms. Two patterns of formant transition were used: (1) formants changing in the direction of, but not reaching, target frequencies (except in the end-point stimulus), and (2) formants reaching F1 and F2 targets. The data were collected with ten normal-hearing and ten hearing-impaired subjects. The boundaries and slopes were determined for four listening conditions: quiet, noise, short reverberation (0.8 s), and long reverberation (1.1 s). The location of boundaries depended upon: (1) pattern of formant transitions, (2) listening condition, and (3) status of subjects' hearing. Generally, longer transitions were needed for formants changing in the direction of, but not reaching, target frequencies, than for those reaching F1 and F2 targets. The required transition durations were similar in quiet and noise, but were longer in reverberation. The hearing-impaired subjects generally required longer transitions to reach the boundaries than normal-hearing subjects. The slopes of the identification functions were shallower in either noise or reverberation than in quiet and were shallower for hearing-impaired than for normal-hearing subjects. In reverberation, the slopes for formants reaching targets were shallower than the slopes for stimuli with formants changing in the direction of target frequencies. The relationships between these findings and identification errors for naturally produced tokens of the diphthong /aI/ are discussed.
- Published
- 1994
- Full Text
- View/download PDF
49. Vowel boundaries for steady-state and linear formant trajectories.
- Author
-
Nábĕlek AK, Czyzewski Z, and Crowley HJ
- Subjects
- Acoustic Stimulation, Adult, Aged, Audiometry, Audiometry, Pure-Tone, Female, Hearing physiology, Hearing Loss, Bilateral physiopathology, Humans, Male, Middle Aged, Noise, Phonetics, Speech Perception, Hearing Loss, Bilateral diagnosis
- Abstract
Locations of boundaries and slopes of identification functions were tested for /I-epsilon/ vowel continua with steady-state and linearly changing formant trajectories. In experiment 1, the boundaries and slopes for arbitrarily selected trajectory directions were determined for ten normal-hearing and ten hearing-impaired subjects in three listening conditions: Quiet, noise, and reverberation. The boundaries did not depend upon the group of subjects or the listening condition. A boundary shift was found for stimuli with F1 changing in a downward direction relative to boundaries for stimuli with either only F1 or with both F1 and F2 changing in an upward direction. The slope of the identification function for stimuli with F1 changing in a downward direction was shallower than the slopes for stimuli with steady-state formants or stimuli with F1 changing in an upward direction. The slopes obtained from the hearing-impaired subjects were shallower than those of the normal-hearing subjects and were shallower in noise than in either quiet or reverberation. In experiment 2, boundaries and slopes for the trajectory directions found in the natural vowels /I/ and /epsilon/, F1 changing in an upward direction and F2 in a downward direction, were determined for nine normal-hearing subjects in two listening conditions, quiet and reverberation. The boundary for stimuli with both F1 and F2 changing in directions characteristic for natural vowels was shifted relative to the boundary for stimuli with steady-state formants. The directions of the boundary shifts in experiments 1 and 2 indicated a perceptual emphasis on the initial sections of changing F1 and F2. Sound quality of the end-point /I/ and /epsilon/ stimuli depended upon F1 and F2 trajectories. For both vowels, the best quality judgments were found for the stimuli with natural F1 and F2 trajectory directions. The quality judgments were weakly correlated with the slopes of identification functions, with better quality judgments being associated with steeper slopes.
- Published
- 1993
- Full Text
- View/download PDF
50. Internalization of surfactant protein A (SP-A) into lamellar bodies of rat alveolar type II cells in vitro.
- Author
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Kalina M, McCormack FX, Crowley H, Voelker DR, and Mason RJ
- Subjects
- Animals, Cell Size, Cells, Cultured, Endocytosis, Male, Organelles metabolism, Organelles ultrastructure, Pulmonary Alveoli ultrastructure, Pulmonary Surfactant-Associated Protein A, Pulmonary Surfactant-Associated Proteins, Rats, Rats, Sprague-Dawley, Proteolipids metabolism, Pulmonary Alveoli metabolism, Pulmonary Surfactants metabolism
- Abstract
Pulmonary surfactant is thought to be internalized and processed for reuse by alveolar Type II cells. In the present study we followed the internalization and intracellular trafficking of purified surfactant protein A (SP-A) by primary cultures of alveolar Type II cells. Internalization of native rat SP-A was compared with that of recombinant rat and human SP-A isolated from a patient with alveolar proteinosis. All SP-A species were conjugated with colloidal gold for visualization by electron microscopy. The gold conjugates were biologically active, as demonstrated by inhibition of phospholipid secretion from alveolar Type II cells. The SP-A-gold conjugates were internalized to lamellar bodies (LB) via the endosomal system, which included both electron-lucent and -dense multivesicular bodies. Labeling of LB was time dependent, and after 7 hr 30-40% of these organelles were labeled. Alkylation of SP-A greatly reduced internalization, as did an excess of non-conjugated SP-A. No qualitative differences in uptake were observed with the three forms of SP-A. The percent of labeled LB was similar (30-40%) after 7 hr of internalization with the three species of SP-A. The recombinant SP-A produced using a baculovirus vector lacked hydroxyproline and had an altered oligosaccharide, but these features did not affect its internalization or the rate of LB labeling. Internalization of the gold-conjugated SP-A and endocytosis of the fluid-phase marker Lucifer Yellow were related to the shape of Type II cells. Both uptake of SP-A, which is receptor mediated, and fluid-phase endocytosis were found to be less active in the flattened than in the rounded cells. Therefore, cell shape and hence cytoskeletal organization may play an important role in SP-A recycling. However, it is possible that both morphology and decreased endocytosis are independent manifestations related to the loss of differentiated function of cultured Type II cells.
- Published
- 1993
- Full Text
- View/download PDF
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