bluuebunny/crossref_metadata_2025_split huggingface dataset:
An in vitro evaluation of the accuracy of Dentaport ZX apex locator in enlarged root canals
Authors: Ebrahim AK , Wadachi R. , Suda H. 
Published: March 2008

Abstract Background: The aim of this study was to examine the effects of root canal irrigants on the accuracy of Dentaport ZX™® electronic apex locator (EAL) in enlarged root canals. Our previous study revealed that as the diameter of the root canal increased, the electronically measured length with small size files became shorter in the presence of blood. It is not known whether different canal irrigants would interfere with the reading accuracy of an EAL in enlarged root canals. Methods: A total of 45 extracted single‐rooted human teeth were used. In Stage 1, canals were instrumented using #10–40 K‐files with a #40 K‐file as the master apical file (MAF). The teeth were randomly divided into five groups and mounted in an experimental apparatus. The following irrigants were used during electronic canal measurements: Group A = 0.5% NaOCl; Group B = 2.5% NaOCl; Group C = 15% EDTA; Group D = 0.8% chlorhexidine (CHX); and Group E = RC Prep. In Stage 2, the canals were enlarged using a #60 K‐file as the MAF. In Stages 1 and 2, the apical portion of the canals was instrumented using the step‐back sequence (up to a #80 K‐file). In Stage 3, the canals were enlarged again using a #80 K‐file as the MAF. In each stage, the canal length was measured with a Dentaport ZX™® using #10 and #40, #10 and #60, and #10 and #80 K‐files for Stages 1, 2 and 3, respectively. Data were analysed by two‐way ANOVA and Fisher's PLSD test. Results: Statistical analysis showed significant differences among all groups (p < 0.01). There was no significant difference between Group A and B at each stage and between Group D and E at Stage 2. A statistical significant difference was observed between #10 K‐file and other files (#40, #60 and #80) at each stage (p < 0.01). In Groups A and B, there was no significant difference between #10 and 40 K‐files (Stage 1) and between #10 and #60 K‐ files (Stage 2). Conclusion: The Dentaport ZX™® was accurate and not adversely affected by the presence of 0.5% or 2.5% NaOCl and EDTA in the enlarged canals, and the measured lengths obtained with small and large size files were comparable. However, it was accurate in the presence of CHX and RC Prep only when large size files were used, and the length measured with small size files was greater than the actual length.
Attachment of periodontal fibroblasts to barrier membranes coated with platelet‐rich plasma
Authors: Chang T. , Liu Q. , Marino V. , Bartold PM 
Published: March 2008

Abstract Background: This study evaluated the attachment of human periodontal ligament (HPDL) and human gingival (HG) fibroblasts onto commercially available barrier membranes coated with plateletrich plasma (PRP). Methods: Gore‐Tex® Regenerative Membrane (GTN1), Inion GTR® Biodegradable system (INION), and Gore‐Resolut XT Regenerative membrane (GTRX) were studied. The membranes were pre‐wetted with phosphate buffered saline before exposure to PRP for two hours. HPDL or gingival fibroblasts were then seeded onto the membranes and incubated in culture medium for 24 hours. The samples were then fixed and processed for light and scanning electron microscopy evaluation. Results: PRP‐coated membranes showed greater cell attachment compared to non‐coated membranes. The INION membrane showed the greatest attachment followed by the GTN1 and GTRX membranes. The cells showed increased cytoplasmic extensions and appeared more intertwined around individual fibres of the membranes compared to uncoated control membranes. Conclusion: HPDL and HG fibroblasts have a distinct reaction with different membranes depending on both microstructure and composition of the membrane. Coating membranes with PRP had a significant impact on the way HPDL and HG fibroblasts attach to certain barrier membranes by increasing both the amount and the quality of attachment.
Factors involved in the translation of continuing professional development programmes into clinical practice among Victorian dentists
Authors: John V. , Parashos P. 
Published: March 2008

Abstract Background: Continuing professional development (CPD) programmes have traditionally been seen as an important means by which dentists keep up‐to‐date with current advances in the field. Recent legislative changes in Victoria have resulted in the introduction of mandatory CPD for dentists. Despite this, there is limited available information on the effectiveness of the translation of these programmes into clinical practice. Methods: Participants undertaking CPD programmes in endodontics and implant dentistry were surveyed using three questionnaires over three time‐frames: pre‐CPD, post‐CPD and three months following the programme (delayed). The course format of the programmes involved both didactic lecture and interactive hands‐on components. Results: Overall response rates of 94 per cent for pre‐CPD and post‐CPD questionnaires, and 77 per cent for the delayed impact‐on‐practice questionnaire were achieved. Programmes in both disciplines were found to be effective in facilitating the uptake of the new technologies taught in the courses. The time‐series design of the present survey was effective in identifying dentists' background knowledge, experiences and biases, and in evaluating the translation of CPD programmes into clinical practice. Conclusions: A variety of discipline‐related and participant‐related factors were identified which may influence the uptake of learned concepts and techniques by participants undertaking CPD programmes. Educators must be cognizant of these issues to ensure that these programmes positively impact on clinical practice, in particular the adoption of technological advances or technical aspects and relating it to the biological goals of treatment, thus facilitating an overall improvement in health care outcomes.
Bacteria and salivary profile of adolescents with and without cleft lip and/or palate undergoing orthodontic treatment
Authors: Cheng LL , Moor SL , Kravchuk O. , Meyers IA , Ho CTC 
Published: March 2008

Abstract Background: Patients with cleft lip and/or palate (CL&/P) experience a higher caries prevalence. This study aimed to determine if patients with CL&/P, undergoing and not undergoing orthodontic treatment, have a different salivary biochemical profile and different salivary levels of Mutans Streptococci (MS) and Lactobacilli (LB) compared to patients undergoing and not undergoing orthodontic treatment without CL&/P. Methods: One hundred and ten subjects aged between 12 and 17 years were recruited into one of four different groups comprising two control groups and two treatment groups. The control groups comprised of subjects with and without CL&/P who were not undergoing orthodontic treatment. The treatment groups comprised of subjects with and without CL&/P undergoing orthodontic treatment. Regular reinforcement of oral hygiene instructions, dietary counselling and debridement, when necessary, were offered to subjects in the treatment groups following their orthodontic adjustment appointments. The salivary secretion time, pH of resting and stimulated saliva, salivary flow rate, buffering capacity, quantity of salivary MS and LB were measured. Results: Subjects with CL&/P undergoing orthodontic treatment at the Children's Oral Health Service tended to present with microbiological and salivary profiles that were less favourable for caries development. There was a significant difference in the percentage of subjects with >105 colony forming units (CFU)/mL of MS between the cleft treatment and non‐cleft treatment groups. Subjects in the non‐cleft treatment group had the highest percentage of subjects (86.7 per cent) with >105 CFU/mL of MS whereas subjects in the cleft treatment group had the lowest percentage of subjects (60 per cent) with >105 CFU/mL of MS. For LB, there were significantly higher percentages of subjects with >105 CFU/mL of LB in the non‐cleft treatment (76.7 per cent) and cleft treatment (73.3 per cent) groups compared to the non‐cleft control (46.7 per cent) and cleft control (40.0 per cent) groups. Conclusions: Regular oral hygiene reinforcement and dental health education appears to have a positive effect in reducing the percentage of subjects with >105 CFU/mL of MS.
Interim and temporary restoration of teeth during endodontic treatment
Authors: Jensen A‐L , Abbott PV , Salgado J Castro 
Published: March 2008

AbstractOne of the main aims of endodontic treatment is to eliminate micro‐organisms from within the root canal system. A further aim is to prevent the ingress of any further bacteria during and after treatment. These aims are usually achieved by various means and stages throughout the treatment process. Endodontic treatment is usually performed on teeth that have lost the integrity of the external coronal tooth structure which has allowed bacteria to enter the tooth and ultimately reach the pulp space. Further opening of the tooth occurs when an endodontic access cavity is made to allow treatment to be performed. Hence, there will always be a need for interim and temporary restoration of teeth undergoing endodontic treatment. Many different materials and techniques have been proposed, and these proposals have been based on many research reports. The purposes of this article are to review the literature regarding the use of interim and temporary restorations, and to provide recommendations regarding such restorations for clinicians to follow when providing endodontic treatment.
Estimating leachate drawdown due to pumping wells in landfills
Authors: Rowe R Kerry , Nadarajah Preba 
Published: March 2008

Pumping (extraction, purge) wells in the waste may be proposed as part of the design of new landfills to backup the leachate underdrain system. These wells are intended to control the leachate mound after there has been a failure of the underdrain system. Pumping wells in the waste have also been proposed to reduce the height in old landfills that are not engineered with a leachate underdrain system. Equations are developed herein for use in estimating the well radius/spacing required to control the leachate mound to a specified level for a number of different assumed conditions and hence can be used to aid the design engineer in assessing the viability of pumping wells in the waste as a leachate control measure. The equations consider the hydraulic conductivity of the waste and the percolation through the cover. It is shown that leakage through the landfill base can be readily considered provided that the leakage through the base is less than 80% of the percolation into the landfill. Anisotropy of the waste is considered. Correction factors are also presented to account for the effect of a reduction in hydraulic conductivity around the well due to biotic and abiotic clogging. The use of the equations is illustrated by examples. Key words: pumping wells, landfills, leachate control, design, applications, clogging.
Characteristics of biplanar wedge spoil pile instabilities and methods to improve stability
Authors: Ulusay Resat , Çaglan Dinçer , ArIkan Fehmi , Yoleri M Fatih 
Published: March 2008

The stability of spoil piles in surface coal mines is an important factor in the successful exploitation of coal reserves. Spoil pile instability must be avoided not only to ensure negligible risk in both personnel and equipement but also to prevent increased production costs. Since mining began at the Eskihisar strip coal mine, southwest Turkey, stability problems have been experienced in both spoil piles adjacent to highwalls (slices) and outside dumping areas. This paper outlines the results of field and laboratory investigations performed to describe the causes and mechanism of pile instabilities threatening production along the highwalls. Back-analysis of failures and monitoring data have revealed that failures occur along planar surfaces that define two-wedge shaped blocks. In addition, shear strength of the moist underclay at the base of piles and changes in the floor dip are the controlling factors in the development of failures. It is also noted that sharp decreases in shear strength after peak values for the the underclay indicated that weak basal planes exhibit a shear strength at or approaching the residual value at the time of failure. Results show that failures are most likely initiated along the spoil &#150 natural ground interface and propagate into spoil mass. Three possible remedial measures have been evaluated by carrying out two-dimentional stability analyses, and the most effective method for improving spoil pile stability appeared to be spreading of a rockfill material on the floor after coal production. Key words: back-analysis, biplanar wedge failure, pile instability, rockfill blanket, shear strength.
A geogrid reinforced embarkment on peat over organic silt: a case history
Authors: Rowe R Kerry , Mylleville Brian LJ 
Published: March 2008

The behaviour of an instrumented section of a full-scale geogrid reinforced embarkment constructed on a very soft deposit of peat overlying organic silt is examined. The results of field monitoring are reportd together with engineering properties of the soils obtained from laboratory tests. The behaviour was analyzed using the finite element method, and the calculated performance is shown to be in good agreement with that observed. Key words: geogrid, reinforcement, embankment, peat, organic silt.
Two debris flow modes on Mount Cayley, British Columbia
Authors: Lu Z Y , Cruden D M 
Published: March 2008

The 1963 landslide on Mount Cayley, British Columbia, began at the head of Dusty Creek, a small tributary of Turbid Creek, a major creek draining Mount Cayley, and terminated at the present confluence of Dusty and Turbid creeks. About 5 × 106 m3 of partially saturated, columnar-jointed dacite and weak pyroclastic rocks moved 2.4 km downstream. The depletion zone contained three separate blocks. The landslide deposits have distinct layers that can be traced back to similar bedrock units in the undisturbed material, which are three times thicker. The accumulation zone is divided by two gullys into three blocks, which preserve, much thinned, different but overlapping portions of the volcanic stratigraphy. The 1984 rock slide on Avalache Creek, 0.8 km away, involved tuff breccia, tuff lapilli, and tuff, all easily broken. Its main track ran over thick snow and ice on the bottom of the creek. Differences in water content and displaced material led to different flow modes: the 1963 fragments formed laminar flows, which supported comparatively undeformed central plugs; the turbulent 1984 flow's deposits have no distinct layers. The two modes, laminar flow and turbulent flow, also formed different types of landslide dams. Key words: landslide, debris flow, volcano, British Columbia, tuff, lava.
Viscous behaviour of soil under oedometric conditions
Authors: Niemunis Andrzej , Krieg Stefan 
Published: March 2008

The viscoplastic constitutive theory of Perzyna, and Olszak and Perzyna has been modified and used to model one-dimensional compression of cohesive, normally consolidated soils. Predictions of the model have been compared with the results of a few nonstandard oedometric tests. The model simplifies the one-dimensional creep theory of Yin and Graham by eliminating the traditional concept of plastic strain. Both stress- and strain-controlled tests are discussed. The reference time t0 used in the literature for the description of creep subsequent to a load step has been shown to be a function of the overconsolidation ratio. Key words: compression, consolidation, constitutive modelling, creep, viscosity, relaxation.
Detecting splogs via temporal dynamics using self-similarity analysis
Authors: Lin Yu-Ru , Sundaram Hari , Chi Yun , Tatemura Junichi , Tseng Belle L. 
Published: March 2008

This article addresses the problem of spam blog (splog) detection using temporal and structural regularity of content, post time and links. Splogs are undesirable blogs meant to attract search engine traffic, used solely for promoting affiliate sites. Blogs represent popular online media, and splogs not only degrade the quality of search engine results, but also waste network resources. The splog detection problem is made difficult due to the lack of stable content descriptors.
We have developed a new technique for detecting splogs, based on the observation that a blog is a dynamic, growing sequence of entries (or posts) rather than a collection of individual pages. In our approach, splogs are recognized by their temporal characteristics and content. There are three key ideas in our splog detection framework. (a) We represent the blog temporal dynamics using self-similarity matrices defined on the histogram intersection similarity measure of the time, content, and link attributes of posts, to investigate the temporal changes of the post sequence. (b) We study the blog temporal characteristics using a visual representation derived from the self-similarity measures. The visual signature reveals correlation between attributes and posts, depending on the type of blogs (normal blogs and splogs). (c) We propose two types of novel temporal features to capture the splog temporal characteristics. In our splog detector, these novel features are combined with content based features. We extract a content based feature vector from blog home pages as well as from different parts of the blog. The dimensionality of the feature vector is reduced by Fisher linear discriminant analysis. We have tested an SVM-based splog detector using proposed features on real world datasets, with appreciable results (90% accuracy).
Not quite the average
Authors: Weinreich Harald , Obendorf Hartmut , Herder Eelco , Mayer Matthias 
Published: March 2008

In the past decade, the World Wide Web has been subject to dramatic changes. Web sites have evolved from static information resources to dynamic and interactive applications that are used for a broad scope of activities on a daily basis. To examine the consequences of these changes on user behavior, we conducted a long-term client-side Web usage study with twenty-five participants. This report presents results of this study and compares the user behavior with previous long-term browser usage studies, which range in age from seven to thirteen years. Based on the empirical data and the interview results, various implications for the interface design of browsers and Web sites are discussed.
A major finding is the decreasing prominence of backtracking in Web navigation. This can largely be attributed to the increasing importance of dynamic, service-oriented Web sites. Users do not navigate on these sites searching for information, but rather interact with an online application to complete certain tasks. Furthermore, the usage of multiple windows and tabs has partly replaced back button usage, posing new challenges for user orientation and backtracking. We found that Web browsing is a rapid activity even for pages with substantial content, which calls for page designs that allow for cursory reading. Click maps provide additional information on how users interact with the Web on page level. Finally, substantial differences were observed between users, and characteristic usage patterns for different types of Web sites emphasize the need for more adaptive and customizable Web browsers.
Involvement of Fibroblast Growth Factor Receptor 2 Isoform Switching in Mammary Oncogenesis
Authors: Cha Jiyoung Y. , Lambert Que T. , Reuther Gary W. , Der Channing J. 
Published: March 2008

AbstractWe identified the IIIb C2 epithelial cell–specific splice variant of fibroblast growth factor receptor 2 (FGFR2 IIIb C2) receptor tyrosine kinase in a screen for activated oncogenes expressed in T-47D human breast carcinoma cells. We found FGFR2 IIIb C2 expression in breast carcinoma cell lines and, additionally, expression of the mesenchymal-specific FGFR2 IIIc splice variant in invasive breast carcinomas. FGFR2 IIIc expression was associated with loss of epithelial markers and gain of mesenchymal markers. Although FGFR2 IIIb is expressed in epithelial cells, previous studies on FGFR2 IIIb transformation have focused on NIH 3T3 fibroblasts. Therefore, we compared the transforming activities of FGFR2 IIIb C2 in RIE-1 intestinal cells and several mammary epithelial cells. FGFR2 IIIb C2 caused growth transformation of epithelial cells but morphologic transformation of only NIH 3T3 cells. FGFR2 IIIb C2–transformed NIH 3T3, but not RIE-1 cells, showed persistent activation of Ras and increased cyclin D1 protein expression. NIH 3T3 but not RIE-1 cells express keratinocyte growth factor, a ligand for FGFR2 IIIb C2. Ectopic treatment with keratinocyte growth factor caused FGFR2 IIIb C2–dependent morphologic transformation of RIE-1 cells, as well as cyclin D1 up-regulation, indicating that both ligand-independent and stromal cell–derived, ligand-dependent mechanisms contribute to RIE-1 cell transformation. Our results support cell context distinct mechanisms of FGFR2 IIIb C2 transformation. (Mol Cancer Res 2008;6(3):435–45)
Modulation of Endocrine Pancreas Development but not β-Cell Carcinogenesis by Sprouty4
Authors: Jäggi Fabienne , Cabrita Miguel A. , Perl Anne-Karina T. , Christofori Gerhard 
Published: March 2008

Abstract
Sprouty (Spry) proteins modulate signal transduction pathways elicited by receptor tyrosine kinases (RTK). Depending on cell type and the particular RTK, Spry proteins exert dual functions: They can either repress RTK-mediated signaling pathways, mainly by interfering with the Ras/Raf/mitogen-activated protein kinase pathway or sustaining RTK signal transduction, for example by sequestering the E3 ubiquitin-ligase c-Cbl and thus preventing ubiquitylation, internalization, and degradation of RTKs. Here, by the inducible expression of murine Spry4 in pancreatic β cells, we have assessed the functional role of Spry proteins in the development of pancreatic islets of Langerhans in normal mice and in the Rip1Tag2 transgenic mouse model of β-cell carcinogenesis. β cell–specific expression of mSpry4 provokes a significant reduction in islet size, an increased number of α cells per islet area, and impaired islet cell type segregation. Functional analysis of islet cell differentiation in cultured PANC-1 cells shows that mSpry4 represses adhesion and migration of differentiating pancreatic endocrine cells, most likely by affecting the subcellular localization of the protein tyrosine phosphatase PTP1B. In contrast, transgenic expression of mSpry4 during β-cell carcinogenesis does not significantly affect tumor outgrowth and progression to tumor malignancy. Rather, tumor cells seem to escape mSpry4 transgene expression. (Mol Cancer Res 2008;6(3):468–82)