bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proximity-induced galloping of two interfering circular cylinders
Authors: Bokaian A. , Geoola F. 
Published: April 2006

Experiments were conducted to investigate the response of a rigid two-dimensional elastically mounted smooth circular cylinder, with oscillations restricted to a plane normal to the incident flow, as influenced by the vicinity of an identical fixed body placed inside the wake. The static lift and drag coefficients, as well as the vibration amplitude and frequency of the upstream cylinder as functions of relative position of the pair of cylinders are given. Most measurements were carried out under two conditions of free-stream turbulence. Whilst turbulence decreased the magnitude of drag coefficients, it had no appreciable effect on lift coefficients. The forces on the upstream body were found to be influenced by the proximity to the downstream one in a significant way only when the streamwise spacing is less than two diameters.In the dynamic tests, two kinds of instability, namely a vortex-resonance and galloping, were observed, with the latter only occurring when the downstream cylinder was well submerged in the near wake of the upstream one. The vortex-shedding frequency was always found to lock to oscillation frequency. Whereas the vibration characteristics remained essentially unaffected with changing turbulence intensity, the galloping amplitudes were observed to be sensitive to cylinders’ aspect ratio. A quasi-steady theory was developed to predict the galloping behaviour.
Laminar entrance flow in a curved pipe
Authors: Soh W. Y. , Berger S. A. 
Published: April 2006

The full elliptic Navier–Stokes equations have been solved for entrance flow into a curved pipe using the artificial compressibility technique developed by Chorin (1967). The problem is formulated for arbitrary values of the curvature ratio and the Dean number. Calculations are carried out for two curvature ratios,a/R= 1/7 and 1/20, and for Dean number ranging from 108.2 to 680.3, in a computational mesh extending from the inlet immediately adjacent to the reservoir to the fully developed downstream region.Secondary flow separation near the inner wall is observed in the developing region of the curved pipe. The separation and the magnitude of the secondary flow are found to be greatly influenced by the curvature ratio. As observed in the experiments of Agrawal, Talbot & Gong (1978) we find: (i) two-step plateau-like axial-velocity profiles for high Dean number, due to the secondary flow separation, and (ii) doubly peaked axial-velocity profiles along the lines parallel to the plane of symmetry, due to the highly distorted secondary-flow vortex structure.
Large-scale structures in a forced turbulent mixing layer
Authors: Gaster M. , Kit E. , Wygnanski I. 
Published: April 2006

The large-scale structures that occur in a forced turbulent mixing layer at moderately high Reynolds numbers have been modelled by linear inviscid stability theory incorporating first-order corrections for slow spatial variations of the mean flow. The perturbation stream function for a spatially growing time-periodic travelling wave has been numerically evaluated for the measured linearly diverging mean flow. In an accompanying experiment periodic oscillations were imposed on the turbulent mixing layer by the motion of a small flap at the trailing edge of the splitter plate that separated the two uniform streams of different velocity. The results of the numerical computations are compared with experimental measurements.When the comparison between experimental data and the computational model was made on a purely local basis, agreement in both the amplitude and phase distribution across the mixing layer was excellent. Comparisons on a global scale revealed, not unexpectedly, less good accuracy in predicting the overall amplification.
Developing turbulent boundary layers with system rotation
Authors: Watmuff J. H. , Witt H. T. , Joubert P. N. 
Published: April 2006

Measurements are presented for low-Reynolds-number turbulent boundary layers developing in a zero pressure gradient on the sidewall of a duct. The effect of rotation on these layers is examined. The mean-velocity profiles affected by rotation are described in terms of a common universal sublayer and modified logarithmic and wake regions.The turbulence quantities follow an inner and outer scaling independent of rotation. The effect appears to be similar to that, of increased or decreased layer development. Streamwise-energy spectra indicate that, for a given non-dimensional wall distance, it is the low-wavenumber spectral components alone that are affected by rotation.Large spatially periodic spanwise variations of skin friction are observed in the destabilized layers. Mean-velocity vectors in the cross-stream plane clearly show an array of vortex-like structures which correlate strongly with the skin-friction pattern. Interesting properties of these mean-flow structures are shown and their effect on Reynolds stresses is revealed. Near the duct centreline, where we have measured detailed profiles, the variations are small and there is a reasonable momentum balance.Large-scale secondary circulations are also observed but the strength of the pattern is weak and it appears to be confined to the top and bottom regions of the duct. The evidence suggests that it has minimally affected the flow near the duct centreline where detailed profiles were measured.
The best and worst aspects of the ICU research coordinator role
Authors: Roberts Brigit L , Rickard Claire M , Foote Jonathon , McGrail Matthew R 
Published: April 2006

ABSTRACTBackground : The Research Coordinator (RC) role is a relative new addition to staffing profiles in Australasian Intensive Care Units (ICUs). The RC plays a pivotal role in conducting ethically and scientifically sound research. There have been anecdotal reports of the RC role in various speciality areas. However, limited research has been undertaken into the role, and only one study has been published from the intensive care setting.Aim : To evaluate which factors the RC found to be the best and worst attributes of the role.Methods : A cross‐sectional web‐based cohort study was conducted in 2004 collecting free text information from RCs in ICUs in Australia and New Zealand.Results : Forty‐nine participants (71%) completed the study with 273 entries into the two categories of ‘best’ (60%) and ‘worst’ (40%) aspects of the role. We identified four thematic clusters in both categories: (1) ‘How the job was structured’ (2) ‘The worth of the job’ (3) ‘What the work involves’ and (4) ‘Who I work with’. Both categories received proportionally the same number of responses in each theme with (1) the most frequent and (4) the least number of entries.Conclusion : There is much variation between RCs in almost every descriptor of the role. The Australasian Intensive Care RC values autonomy, respect and intellectual stimulation with the scope for extending the role to suit the individual and finds isolation, under‐recognition and workload, often not sufficiently compensated, to be the worst aspects of the position.
Partnership working between a Higher Education Institution and NHS TRUSTS: developing an acute and critical care module
Authors: Rattray Janice E , Paul Fiona , Tully Vicki 
Published: April 2006

ABSTRACTThe underpinning philosophy of preparing nurses to work within a modern National Health Service (NHS) is to ensure patient safety and quality of clinical care. There is increasing recognition that post‐registration education should become more clinically focused and adopt a more work‐based approach. Critical to the success of such an approach is partnership working between education providers and NHS Trusts. Changes in the delivery of acute care in the NHS have resulted in an increased number of highly dependent patients in both critical and non‐critical care areas. This article describes a partnership approach between a Higher Education Institution (HEI) and two NHS Trusts to deliver a degree level module to address the subsequent educational implications of these changes. This approach ensured module credibility and clinical focus. Student feedback confirms the clinical relevance of the module. Staff from the NHS had the opportunity to develop teaching skills by preparing teaching materials, delivering teaching sessions and receiving feedback on these. Areas of good practice were identified and there was sharing of skills, knowledge and expertise between both institutions. Joint working can enhance clinical relevance of educational provision and ensure consistency between theory and practice. In addition, there were a number of wider benefits to both institutions that resulted from this initiative.
General practitioners’ ranking of evidence‐based prescribing quality indicators: a comparative study with a prescription database
Authors: Okechukwu Ifeanyi , Bennett Kathleen , Feely John 
Published: April 2006

BackgroundTo ensure that indicators for assessing prescribing quality are appropriate and relevant, physicians should be involved in their development. How general practitioners (GPs) rank these indicators is not fully understood.Aims(i) To determine how GPs in Ireland rank a set of evidence‐based prescribing quality indicators in order of importance and relevance to their practice, and (ii) to compare the GPs’ ranking of the defined set of indicators with actual prescribing practice using a prescription database.MethodsA postal questionnaire was sent to 105 GPs, who were asked to rank a set of 11 prescribing quality indicators, identified from the literature from most to least important. The results were aggregated and a weighted score for each indicator determined. These same prescribing indicators were then applied to a prescription database to compare the ranking provided with actual prescribing practice.ResultsEighty‐six GPs (82%) returned the completed questionnaire. The higher ranks were for quality issues—use of inhaled corticosteroids, statins and benzodiazepines. Actual prescribing data showed prolonged use of benzodiazepines in over half of the prescriptions dispensed (n = 18 171), 52.48% (95% confidence interval 51.95, 53.01) and low usage of generic drugs, 17.78% (17.70, 17.90) despite their high ranking by the GPs.ConclusionWhile GPs have diverse views about the value of different prescribing quality indicators, the results suggest that they do rank evidence‐based guidelines on patient management highly, but those based on costs and less evidence the lowest. There was considerable divergence between theory and practice in the application of quality indices.
Long‐term results of an ultra low‐dose cytarabine‐based regimen for the treatment of acute megakaryoblastic leukaemia in children with Down syndrome
Authors: Al‐Ahmari Ali , Shah Niketa , Sung Lillian , Zipursky Alvin , Hitzler Johann 
Published: April 2006

SummaryChildren with acute megakaryoblastic leukaemia (AMKL) and Down syndrome (DS) show a favourable response to chemotherapy, probably due to increased sensitivity of the leukaemic blasts to cytarabine. In contrast, dose‐intensive approaches have resulted in disproportionate treatment‐related mortality in this group. The survival of children with AMKL and DS was retrospectively compared following treatment with a low‐dose chemotherapy protocol, consisting of cytarabine (10 mg/m2/dose), retinylpalmitate and vincristine or standard chemotherapy. Event‐free (67 ± 11%) and overall survival (77 ± 10%) at 5 years were not significantly different in both groups. Further reduction of treatment intensity in AMKL of children with DS, therefore, appears feasible.
Costly melanin ornaments: the importance of taxon?
Authors: STOEHR A. M. 
Published: April 2006

Summary

Experimental work in vertebrates shows that different forms of coloration – particularly carotenoid‐based vs melanin‐based ornaments – are differentially sensitive to stressors such as diet manipulations and parasitic infections. Comparative work also shows that historical patterns of ornament evolution depend on the proximate mechanisms of colour production.
Based on the results from vertebrates, it has been argued that melanin‐based ornaments may not be good indicators of quality because, unlike carotenoid‐based ornaments, melanin pigments can be synthesized from amino acid precursors, and therefore melanin synthesis is unlikely to be costly.
However, there is evidence for costly melanin synthesis in insects, which use melanin in some ways that vertebrates do not. Differences across taxa in the costs of melanin synthesis challenge the generality of the hypotheses relevant to these ornaments.
In general, all pigment‐based ornaments are a function of precursor intake and processing. Differences in costs of melanin synthesis across taxa may reflect differences in one or both of these parameters.
I urge communication between researchers working on related questions in disparate taxa (vertebrates and invertebrates). This should facilitate the discovery of the most fundamental aspects of colour ornament evolution.
Ki67 immunohistochemistry: a valuable marker in prognostication but with a risk of misclassification: proliferation subgroups formed based on Ki67 immunoreactivity and standardized mitotic index
Authors: Jalava P , Kuopio T , Juntti‐Patinen L , Kotkansalo T , Kronqvist P , Collan Y 
Published: April 2006

Aims : Counting mitotic figures is considered to be a reliable prognosticator, but evaluation of Ki67 immunohistochemistry has become more popular in evaluating proliferation. Our previous studies suggested an occasional discrepancy between mitotic figures and Ki67 fraction. The aim of this study was to investigate this more closely and also to study the associations between bcl‐2 and p53 expression and proliferation.Methods and results : Two hundred and sixty‐five infiltrating breast carcinomas were immunostained for Ki67, p53 and bcl‐2. The standardized mitotic index (SMI) was determined. Four proliferation groups were based on Ki67 positivity fraction and SMI at optimal cut‐off points. Cox's multivariate model was used to test the power of the prognosticators. SMI and nodal status were the most powerful individual prognosticators. Ki67 was an independent prognosticator if nodal status, tumour size, age and histological grade were included in the analysis but not if analysed with SMI. The group with low SMI and low Ki67 fraction had the best prognosis. Groups with high SMI had the poorest prognosis. The group with low SMI and high Ki67 fraction had a favourable prognosis. Bcl‐2 negativity and p53 positivity correlated with proliferation.Conclusions : We have found a ‘wrong positive’ Ki67 group with favourable prognosis. SMI cannot be replaced by Ki67 because of the danger of misclassification of some patients.
Immunohistochemistry increases the accuracy of diagnosis of benign papillary lesions in breast core needle biopsy specimens
Authors: Shah V I , Flowers C I , Douglas‐Jones A G , Dallimore N S , Rashid M 
Published: April 2006

Aims : Recent studies have suggested that benign papillary lesions without atypia [benign papilloma (BP)] diagnosed on breast core needle biopsy (CNB) may not require excision. However, most have studied only small numbers of cases and scant data are available on the utility of immunohistochemistry in the categorization of papillary lesions on CNB. In the largest published series of BP identified on CNB, we studied the impact of immunohistochemistry on the accuracy of a CNB diagnosis of BP.Methods and results : Breast CNBs (n = 129) with a diagnosis of papillary lesion were immunostained for calponin, p63 and cytokeratin 5/6. Haematoxylin and eosin and immunostained slides were independently reviewed by four breast pathologists. BP was the final excision diagnosis in 35 cases. With the use of immunohistochemistry, the postive predictive value (PPV) of BP diagnosis by the four individual pathologists increased from 72.7–83.3% (mean 79.2%) to 77.8–87.5% (82.1%), the negative predictive value (NPV) increased from 77.8–98.5% (88.6%) to 100% for all four participants and overall accuracy increased from 78.7–92.6% (84.7%) to 90.7–95.4% (92.8%). No case of invasive carcinoma was diagnosed as BP on CNB by any participant. The frequency of ductal carcinoma in situ following a BP diagnosis on CNB ranged from 2.5% to 4.8% (4%) but was only 0–3% (2.3%) after excluding cases that were radiologically suspicious for malignancy.Conclusions : Immunohistochemistry increases accuracy of BP diagnosis in CNB specimens. Benign papillary lesions diagnosed on CNB do not require excision in the absence of suspicious clinical/radiological findings.
Detailed analysis of the T‐cell lymphocytic infiltrate in penile lichen sclerosus: an immunohistochemical and molecular investigation
Authors: Regauer S , Beham‐Schmid C 
Published: April 2006

Aim : To determine the extent of clonal outgrowth in the lymphocytic tissue infiltrate of lichen sclerosus (LS). The presence of T cells with a monoclonally rearranged T‐cell receptor γ‐gene (TCRγ) has been described in up to 50% of biopsies of vulvar and penile LS.Material and results : We analysed 33 foreskin specimens with LS for the presence of clonal T cells by conventional polymerase chain reaction (PCR) analysis and with TCRγ‐PCR‐based fluorescent fragment analysis. Eighteen of 33 patients revealed a band indicating a monoclonally rearranged TCRγ on conventional PCR analysis. Subsequent TCRγ‐PCR‐based fluorescent fragment analysis identified 8/18 patients with monoclonal T‐cell DNA ranging from 1.4% to 23.1% of total T‐cell DNA analysed and a size range from 56 to 72 base pairs. Four of 18 patients had an oligoclonal and 6/18 patients revealed a polyclonal banding pattern. The lymphocytic infiltrate contained low numbers of γδ T cells and cytotoxic T cells in comparable numbers to the low percentage of clonal TCRγ DNA.Conclusions : The low percentage of clonal TCRγ DNA argues against a systemic neoplastic disease, but rather for a local immune disorder. The target antigen of the clonal outgrowth is unknown, but an exaggerated antigen‐dependent proliferation of T cells due to chronic local antigen exposure, probably an infectious antigen, is the most likely explanation.
Does life‐history variability in salmonids affect habitat use by juveniles? A comparison among streams open and closed to anadromy
Authors: MORINVILLE GENEVIÈVE R. , RASMUSSEN JOSEPH B. 
Published: April 2006

Summary

Migratory and resident forms of salmonids coexist in many river systems. Although such coexistence is widespread, little is known about its ecological basis and no studies have compared the habitat use of premigratory juveniles and residents.
We employed a comparative approach to explore the differential habitat use of juvenile anadromous and resident brook trout. This required the investigation of habitat use in streams closed to anadromy, containing only resident brook trout Salvelinus fontinalis (‘resident‐only’ streams) and streams open to anadromy, containing coexisting Atlantic salmon Salmo salar and anadromous and resident brook trout (‘migrant‐resident’ streams).
We demonstrate that fast habitats (riffles) are occupied more frequently in streams with migratory brook trout relative to riffle habitats of streams with only resident brook trout. In contrast, occupation of slow current velocities (pools) was observed in both migrant‐resident and resident‐only streams as both stream types contain resident brook trout. The net effect is a wider distribution of occupied habitats (pool and riffles) in migrant‐resident streams relative to resident‐only streams, resulting in few, if any, unused habitats.
These results are consistent with previously reported bioenergetic, morphological and stable isotope differences observed between anadromous and resident brook trout.
Our findings suggest that a link exists between juvenile habitat use, metabolic costs and life‐history strategies.
Associations between apolipoprotein B, apolipoprotein AI, the apolipoprotein B/AI ratio and coronary heart disease: a literature‐based meta‐analysis of prospective studies
Authors: THOMPSON A. , DANESH J. 
Published: April 2006

Abstract.Objectives.  To assess associations of circulating levels of apolipoprotein (apo) AI, apoB and the apoB/AI ratio (apoB/A) with risk of incident coronary heart disease (CHD).Design.  Literature‐based meta‐analysis of prospective studies.Data sources.  Prospective studies in essentially general populations that reported on associations between apoAI, apoB or apoB/A and first incident CHD outcomes. Studies were identified by computer‐based searches and by manual searches of the relevant literature.Results.  Data from 23 relevant studies were identified. For apoAI, with 6333 CHD cases in 21 studies, comparison of individuals in the bottom third with those in the top third of baseline values yielded a combined relative risk of 1.62 (95% confidence interval: 1.43–1.83), i.e. an inverse association. For apoB, a combined analysis of 6320 CHD cases from 19 studies gave a relative risk of 1.99 (1.65–2.39) for a comparison of individuals in the top third versus those in the bottom third of baseline values. For apoB/A, with 3730 CHD cases from seven studies, a comparison of individuals in the top third versus the bottom third of baseline values gave a combined relative risk of 1.86 (1.55–2.22). These associations were somewhat stronger following correction for within‐person variations in apolipoprotein levels. There was evidence of heterogeneity amongst the published studies, but it was only partly explained by available study‐level characteristics.Conclusions.  The present quantitative review suggests the existence of moderately strong associations between baseline levels of each of apoAI, apoB, and apoB/A and risk of CHD. More detailed analysis, perhaps based on individual participant data from prospective studies, could help to overcome several limitations in the present review and to clarify any relevance of these apolipoproteins to disease prediction and aetiology.
Measurement and meaning of apolipoprotein AI and apolipoprotein B plasma levels
Authors: MARCOVINA S. , PACKARD C. J. 
Published: April 2006

Abstract.Apolipoproteins AI and B are structural components of lipoprotein particles, and also determinants of the metabolic fate of the encapsulated lipid, cholesterol and triglyceride. Development of accurate assays for these apolipoproteins has opened the way for their use as predictors of coronary heart disease risk. Interpretation of AI and apo B levels is best undertaken with background knowledge of the metabolic status of an individual, especially the lipolytic capacity as reflected in the triglyceride concentration. Those with raised triglyceride, in general, not only have an elevated apo B/apo AI ratio, but also apo B‐containing lipoproteins with a prolonged residence time and hence ample opportunity for modification and damage. Assessment of apolipoprotein levels is an aid to risk prediction and can be useful in tailoring treatment.