bluuebunny/crossref_metadata_2025_split huggingface dataset:
Defining Left Ventricular Hypertrophy in Children on Peritoneal Dialysis
Authors: Borzych Dagmara , Bakkaloglu Sevcan A. , Zaritsky Joshua , Suarez Angela , Wong William , Ranchin Bruno , Qi Cao , Szabo Attila J. , Coccia Paula A. , Harambat Jérôme , Mitu Florin , Warady Bradley A. , Schaefer Franz 
Published: July 2011

Summary

Background and objectives
Left ventricular hypertrophy (LVH) is an important end point of dialysis-associated cardiovascular disease. The objective of this study was to evaluate the effect of different pediatric reference systems on the estimated prevalence of LVH in children on chronic peritoneal dialysis (CPD).

Design, setting, participants, & measurements
Echocardiographic studies in 507 pediatric CPD patients from neonatal age to 19 years were collected in 55 pediatric dialysis units around the globe. We compared the prevalence of LVH on the basis of the traditional cutoff of left ventricular mass (LVM) index (>38.5 g/m2.7) with three novel definitions of LVH that were recently established in healthy pediatric cohorts.

Results
Application of the new reference systems eliminated the apparently increased prevalence of LVH in young children obtained by the traditional fixed LVM index cutoff currently still recommended by consensus guidelines. However, substantial differences of LVM distribution between the new reference charts resulted in a marked discrepancy in estimated LVH prevalence ranging between 27.4% and 51.7%.

Conclusions
Although our understanding of the anthropometric determinants of heart size during childhood is improving, more consistent normative echocardiographic data from large populations of healthy children are required for cardiovascular diagnostics and research.
Effect of C-factor on Microtensile Bond Strengths of Low-Shrinkage Composites
Authors: El-Sahn NA , El-Kassas DW , El-Damanhoury HM , Fahmy OM , Gomaa H , Platt JA 
Published: July 2011

SUMMARY
This study evaluated the microtensile bond strength (μ-TBS) of low-shrinkage composites with their corresponding adhesive systems, Filtek Silorane/Silorane adhesive (SIL, 3M ESPE AG, Seefeld, Germany) and Aelite LS/One-Step Plus (AL, BISCO Inc, Schaumburg, IL, USA) in cavities with different C-factors. Filtek Z250/Adper Single Bond Plus (Z, 3M ESPE, St Paul, MN, USA) was used as a control.

Method
Standardized Class I cavities were prepared in extracted human molars after removing occlusal enamel. Cavities were assigned into six different C-factors by applying nail polish to four walls, three walls, two walls adjacent to each other, two walls opposite to each other, one wall, or no walls. Resin composites with their corresponding adhesive systems were applied according to manufacturer instructions. Specimens were sectioned to obtain four rectangular beams from the center of the restorations and μ-TBS was measured. Data were analyzed by Weibull survival analysis. Shrinkage stresses of the resin composites were determined after 30 minutes from the start of light-curing using a tensometer testing machine. Flexure elastic modulus was determined using standard procedures, in accordance with ISO 4049. Data for shrinkage stress and elastic modulus were analyzed by one-way analysis of variance followed by a Tukey multiple-comparisons test (p&lt;0.05).

Results
μ-TBS of both SIL and AL were not affected by different C-factors; however, the bond strength of Z decreased significantly when the C-factor increased. Shrinkage stress results were 0.94±0.1, 1.79±0.18, and 2.14±0.23 MPa for SIL, AL, and Z, respectively. The flexural modulus of both the SIL and the AL was significantly lower than that of Z.

Conclusions
Increasing C-factor did not negatively affect the bond strength of low-shrinkage composites.
Creating Tight Proximal Contacts for MOD Resin Composite Restorations
Authors: Saber MH , El-Badrawy W , Loomans BAC , Ahmed DR , Dörfer CE , El Zohairy A 
Published: July 2011

SUMMARYObjectiveThe purpose of this study was to compare proximal contact tightness (PCT) of MOD resin composite restorations placed with different matricing protocols.MethodsForty-five ivorine lower right first molars with standardized MOD cavities were equally divided into three groups according to the restoration protocol. Group 1: Sectional matrix (Standard matrix, Palodent, Dentsply) secured with a wedge (Premier Dental Products Co.) and separation ring (BiTine I, Palodent, Dentsply, York, PA, USA) was used to restore the mesial surface first and then removed and repeated for the distal surface. Group 2: Identical to group 1, but separation rings were placed at both the mesial and distal sides (BiTine I+II, Palodent) prior to restoration. Mesial surface was restored followed by distal. Group 3: Walser matrix (O-form, Dr. Walser Dental GmbH) was used. Following composite resin restoration, PCT was measured using the tooth pressure meter. Data were analyzed using analysis of variance and a Tukey post hoc test (p&lt;0.05).ResultsPCT values for mesial contacts were 2.99 ± 0.47N for group 1, 4.57 ± 0.36N for group 2, and 3.03 ± 0.79N for group 3. For the distal contacts, the values were 4.46 ± 0.44N for group 1, 5.12 ± 0.13N for group 2, and 0.76 ± 0.77N for group 3. Significantly tighter contacts were obtained for mesial and distal contacts for group 2 compared to groups 1 and 3 (p&lt;0.05). For groups 1 and 3, mesial contacts were not significantly different (p=0.993), while distal contacts for group 1 were significantly tighter (p&lt;0.001).ConclusionWithin the limitations of this study, tighter contacts can be obtained when sectional matrices and separation rings are applied to both proximal surfaces prior to placement of the resin composite in MOD cavities.
Microleakage and Marginal Gap of Adhesive Cements for Noble Alloy Full Cast Crowns
Authors: Hooshmand T , Mohajerfar M , Keshvad A , Motahhary P 
Published: July 2011

SUMMARY
Very limited comparative information about the microleakage in noble alloy full cast crowns luted with different types of adhesive resin cements is available. The purpose of this study was to evaluate the microleakage and marginal gap of two self-adhesive resin cements with that of other types of adhesive luting cements for noble alloy full cast crowns. Fifty noncarious human premolars and molars were prepared in a standardized manner for full cast crown restorations. Crowns were made from a noble alloy using a standardized technique and randomly cemented with five cementing agents as follows: 1) GC Fuji Plus resin-modified glass ionomer cement, 2) Panavia F 2.0 resin cement, 3) Multilink Sprint self-adhesive resin cement, 4), Rely X Unicem self-adhesive resin cement with pretreatment, and 5) Rely X Unicem with no pretreatment. The specimens were stored in distilled water at 37°C for two weeks and then subjected to thermocycling. They were then placed in a silver nitrate solution, vertically cut in a mesiodistal direction and evaluated for microleakage and marginal gap using a stereomicroscope. Data were analyzed using a nonparametric Kruskal-Wallis test followed by Dunn multiple range test at a p&lt;0.05 level of significance. The Rely X Unicem (with or with no pretreatment) exhibited the smallest degree of microleakage at both tooth-cement and cement-crown interfaces. The greatest amount of microleakage was found for Panavia F 2.0 resin cement followed by GC Fuji Plus at both interfaces. No statistically significant difference in the marginal gap values was found between the cementing agents evaluated (p&gt;0.05). The self-adhesive resin cements provided a much better marginal seal for the noble alloy full cast crowns compared with the resin-modified glass ionomer or dual-cured resin-based cements.
Effect of Light Activation on Tooth Sensitivity After In-Office Bleaching
Authors: Kossatz S , Dalanhol AP , Cunha T , Loguercio A , Reis A 
Published: July 2011

SUMMARY
This clinical study evaluated the effects of light-emitting diode (LED)/laser activation on bleaching effectiveness (BE) and tooth sensitivity (TS) during in-office bleaching. Thirty caries-free patients were divided into two groups: light-activated (LA) and non-activated (NA) groups. A 35% hydrogen peroxide gel (Whiteness HP Maxx, FGM Dental Products, Joinville SC, Brazil) was used in three 15-minute applications for both groups. For the LA group, LED/laser energy (Whitening Lase Light Plus, DMC Odontológica, São Carlos SP, Brazil) was used, in accordance with the manufacturer's directions. Two sessions of bleaching were performed at one-week intervals. Color was registered at baseline and after the first and second bleaching sessions using a Vita shade guide. Patients recorded TS on a 0 to 4 scale during bleaching and within the next 24 and 48 hours of each session. BE at recall each week and intensity of TS were evaluated by repeated measures analysis of variance (ANOVA) and Tukey tests (α=0.05). Tooth sensitivity was compared using the Friedman repeated measures analysis of variance by rank and the Wilcoxon sign-ranked test. Faster bleaching was observed for the LA group than for the NA group after the first session (4.8 and 3.8 shade guide units [SGUs]; p=0.0001). However, both techniques were capable of bleaching the same number of SGUs after the second bleaching session (p=0.52). Most of the LA group (53.3%) had sensitivity even 24 hours after each bleaching session, but only 26.6% from the NA group reported TS. The intensity of TS was similar for both groups immediately after bleaching but significantly higher for the LA group 24 hours after each bleaching session (p=0.001). After two bleaching sessions, the use of LED/laser light activation did not improve bleaching speed. Persistent tooth sensitivity and higher tooth sensitivity after 24 hours of bleaching were observed when light activation was used.
Effects of Different Surface Conditioning Methods on the Bond Strength of Composite Resin to Amalgam
Authors: Özcan M , Koolman C , Aladag A , Dündar M 
Published: July 2011

SUMMARY
Repairing amalgam restorations with composite resins using surface conditioning methods is a conservative treatment approach. This study investigated the effects of different conditioning methods that could be used for repair of amalgam fractures. Amalgam (N=96) was condensed into cavities within autopolymerizing polymethylmethacrylate (PMMA), and the exposed surface of each specimen (diameter, 6 mm; thickness, 2 mm) was ground finished. The specimens were randomly divided into nine experimental groups (n=12 per group), depending on the conditioning method used. The control group had natural central incisors with amalgam (n=12). The combination of the following conditioning methods was tested: silicacoating (Sc), sandblasting (Sb), metal primers, coupling agents, fiber (Fb) application, and opaquers (O). Five types of silanes, metal primers, or adhesives (Visiobond [V], Porcelain Photobond [PP], Alloy Primer [AP], Unibond sealer [Us], ESPE-Sil [ES]), and four opaquers, namely, Clearfil St Opaquer (CstO), Sinfony (S), Miris (M), and an experimental Opaquer (EO-Cavex), were used. The groups were as follows: group 1, Sc+ES+S+V; group 2, Sc+ES+CstO+V; group 3, Sc+ES+M+V; group 4, Sc+ES+EO+V; group 5, Sb+AP+S; group 6, Sb+AP+PP+CstO; group 7, Sc+ES+S+Fb+V+Fb; group 8-control, SC+ES+V; and group 9, Etch+Sc+ES+S+Us. One repair composite was used for all groups (Clearfil Photo Bond Posterior, Kuraray, Tokyo, Japan). Shear bond strengths (SBSs) (MPa ± SD) were evaluated after 5 weeks of water storage (analysis of variance [ANOVA], Tukey honestly significant differences [HSD], α=0.05). Group 1 exhibited significantly higher values (35.5 ± 4.1) than were seen in group 4 (19.4 ± 8.9), group 6 (19.1 ± 7.8), and group 8 (20.1 ± 4.1) (p&lt;0.05). Group 9 exhibited significantly lower values (8.3 ± 3.4) than were noted in groups 1 to 3 (35.5 ± 4.1; 27 ± 12.5; 24.4 ± 5.1, respectively) (p&lt;0.05). Group 7 (16.4 ± 5.9) showed significantly lower values than were observed in group 1 (35.5 ± 4.1) (p&lt;0.05). Surface conditioning techniques affected the bond strengths of composite adhesion to amalgam. Experimental opaquer exhibited lower values. Leaving a small border of enamel around the restoration decreased the bond strength.
A Systematic Technique for Carving Amalgam and Composite Restorations
Authors: Kilistoff A 
Published: July 2011

SUMMARYBoth amalgam and composite restorations can quickly and accurately be carved using a systematic technique. By following the outlined steps, anatomically accurate restorations can be easily achieved. Inlay wax is used as a training medium to negate the setting constraints and as a high fidelity simulation.
Output statistics of a line enhancer based on a combination of two adaptive filters
Authors: Tõnu Trump 
Published: July 2011

AbstractThis paper studies output statistics of an adaptive line enhancer that is based on an affine combination of two NLMS adaptive filters. Combination of adaptive filters is a new interesting way of improving the performance of adaptive algorithms. The structure consists of two adaptive filters that adapt on the same input signal, one with a large and the other one with a small step size. Such a combination is capable of achieving fast initial convergence and small steady state error at the same time. In this paper we investigate the second order statistics of the output signal of adaptive line enhancer based on the combination in steady state. The result is given in terms of the parameters of the adaptive combination, input process statistics, and the optimal Wiener filter weights for the problem at hands.
More malfunctioning Medos Hakim programmable valves: cause for concern?
Authors: Mauer Uwe Max , Kunz Ulrich 
Published: July 2011

Object
In recent years, the authors have noticed a growing number of programmable valve defects at their institution. Therefore, they conducted this study to evaluate the increased incidence of malfunctioning valves.

Methods
They investigated all revisions that had been performed at their institution between 1994 and 2010 for dislodgement of the stator of a standard Medos Hakim programmable valve with a prechamber.

Results
Fifteen valves were removed because of dislodged stators. The valves had been implanted between May 16, 1993, and December 27, 2002, and were explanted between February 19, 2006, and January 22, 2010. Thus, the valves had been in place for a mean period of 11 years (median 11 years, range 7–14 years). The percentage of dislodged stators was almost 3% (15 of 546 valves). Particularly noteworthy is that all malfunctioning valves were found in children who had been younger than 1 year of age at the time of implantation.

Conclusions
Medos Hakim programmable valve malfunctions are rare events but should receive careful attention. When the pressure setting cannot be adjusted, a malfunction should always be suspected and radiographic imaging should be performed to assess the valve. Stator dislodgement is the most serious form of valve adjustment failure.
Bilateral subfrontal approach for tuberculum sellae meningiomas in long-term postoperative visual outcome
Authors: Chokyu Isao , Goto Takeo , Ishibashi Kenichi , Nagata Takashi , Ohata Kenji 
Published: July 2011

ObjectVarious surgical approaches, such as uni- and bifrontal, frontolateral, and pterional approaches, have been advocated for tuberculum sellae meningiomas. The authors retrospectively reviewed the effectiveness of a bilateral subfrontal approach for tuberculum sellae meningiomas with special attention to ophthalmological outcomes and complications.MethodsBetween 1993 and 2009, 34 patients underwent surgery for removal of tuberculum sellae meningiomas at Osaka City University. Tumor size ranged from 14 to 45 mm. Thirty-two of 34 patients presented with visual disturbances before the surgery. The visual functions in all patients were assessed using a visual impairment score (VIS) before and after surgery. Postoperative visual examination was performed 2 weeks after surgery. Long-term follow-up examinations were conducted 1 year after surgery.ResultsRadical resection (Simpson Grades I and II) was accomplished in 27 patients, and subtotal or partial resection (Simpson Grades III and IV) was achieved in 7. There was no deterioration in postoperative visual outcome. Twenty-nine (90.6%) of 32 patients showed improved VIS compared with preoperative VIS. The average VIS was 38.1 preoperatively, 23.5 in the short-term postoperative period, and 21.8 in the long-term postoperative period. In the short-term postoperative period, the visual function in 6 patients normalized, and visual problems persisted in the remaining 26. Six (23%) of 26 patients showed further improvement in VIS during the long-term follow-up period, and no patient exhibited a worsened VIS during this time. One patient complained of hyposmia after surgery, but there was no indication of related complications such as CSF leakage or frontal brain contusion.ConclusionsThe bilateral subfrontal approach was previously avoided because of the relatively high rate of complications in earlier surgical series of tuberculum sellae meningiomas. However, after developments in microsurgical techniques in recent years, the bilateral subfrontal approach can now provide satisfactory visual outcomes with minimal postoperative complications. Careful preservation of the blood supply to optic apparatus and early unroofing of the optic canal using a bilateral subfrontal approach led to further improvement in long-term postoperative visual outcome.
Nodular enhancement within the internal auditory canal following retrosigmoid vestibular schwannoma resection: a unique radiological pattern
Authors: Carlson Matthew L. , Van Abel Kathryn M. , Schmitt William R. , Driscoll Colin L. W. , Neff Brian A. , Lane John I. , Link Michael J. 
Published: July 2011

Object
The authors describe the unique occurrence of nodular enhancement within the fundus of the internal auditory canal (IAC) lateral to the preoperative radiological tumor margin following gross-total vestibular schwannoma (VS) resection.

Methods
The nature of the study was a retrospective chart review of records. The authors reviewed the cases of all patients who underwent microsurgical resection of a VS between January 2000 and January 2010 at a single tertiary referral center. Patients with incomplete resection, neurofibromatosis Type 2, and those with fewer than 2 postoperative MR images available for review were excluded.
Postsurgical patients with IAC enhancement located lateral to the preoperative imaging–delineated tumor margin were identified. Lesion morphology was characterized on serial MR imaging studies. Clinical follow-up and outcomes were recorded.

Results
Over the past decade, 350 patients underwent microsurgical VS resection. Of these, 16 patients met study criteria and were found to have postsurgical enhancement in the distal aspect of the IAC lateral to the imaging limits of the preoperative tumor margin on the first postoperative MR imaging study (37.5% women, median age 45 years). Initial MR imaging was performed at a mean of 3.1 months following surgery, and the mean radiological follow-up duration was 39.8 months (range 16.4–101.9 months). None of the 16 patients developed recurrence during the follow-up course.

Conclusions
In contrast to previous publications that have reported a high rate of recurrence in cases involving nodular enhancement within the original tumor bed, postoperative enhancement in the IAC lateral to the original tumor margin appears to carry much less risk for tumor recurrence. These findings may be helpful when counseling patients on the recommended frequency of postoperative follow-up imaging.
Disc spaces, vertebral dimensions, and angle values at the lumbar region: a radioanatomical perspective in spines with L5–S1 transitions
Authors: Mahato Niladri Kumar 
Published: July 2011

ObjectLow-back pain (LBP) has been associated with lumbar spines of normal morphology as well as those with L5–S1 “transitional” vertebrae. It is hard to find literature that quantifies the overall morphological changes in lumbar spines as related to transitional states. The object of this study was to investigate lumbar spine changes resulting from the presence of these transitional states.MethodsThe author quantified dimensions and angles and statistically compared the morphology of lumbar spines with or without L5–S1 transitions in the context of LBP. Anteroposterior and lateral radiographs were obtained from 50 patients suffering from LBP without transitional anomalies at the L5–S1 junction. These radiographs were compared with anteroposterior and lateral radiographs from patients suffering from LBP with L5–S1 transitional states involving accessory L5–S1 articulations, and with anteroposterior and lateral radiographs from patients with L5–S1 unilateral or bilateral fusions. Twelve linear dimensions from the anteroposterior views and 8 angles from the lateral radiographs were measured.ResultsThe mean values of linear dimensions differed in 1) disc heights, 2) vertebral heights and widths, 3) pedicles and interpedicular distances, 4) angle values, and 5) overall configuration of the lumbar curvatures.ConclusionsThe L5–S1 accessory articulations led to increased lordotic curves, L-5 vertebral heights, and pedicle and angular dimensions. The L5–S1 fusions were related to smaller disc heights at all spaces, short and wide L-5 pedicles, taller and less wide transverse processes, and overall straighter spines with the least measures for all lumbar angles. Dimensional differences provided in this study may help in placing instrumentation at the lumbar vertebrae and working on intervertebral disc replacements in spines with specific L5–S1 transitional anomalies.
Left Invariant Einstein–Randers Metrics on Compact Lie Groups
Authors: Wang Hui , Deng Shaoqiang 
Published: July 2011

AbstractIn this paper we study left invariant Einstein–Randers metrics on compact Lie groups. First, we give a method to construct left invariant non-Riemannian Einstein–Randers metrics on a compact Lie group, using the Zermelo navigation data. Then we prove that this gives a complete classification of left invariant Einstein–Randers metrics on compact simple Lie groups with the underlying Riemannian metric naturally reductive. Further, we completely determine the identity component of the group of isometries for this type of metrics on simple groups. Finally, we study some geometric properties of such metrics. In particular, we give the formulae of geodesics and flag curvature of such metrics.
3-D Numerical Simulations of Biofilm Flows
Authors: Chen Chen , Ren Mingming , Srinivansan Ashok , Wang Qi 
Published: July 2011

AbstractWe study the biofilm-flow interaction resulting in biofilm growth and deformation in a water channel in a 3-D setting using the phase field model developed recently. In this biofilm model, the biofilm made up of the EPS, bacteria and solvent is tracked using a biofilm volume fraction which vanishes outside the biofilm region. The interface between the biofilm and the solvent is marked by the zero level surface of the volume fraction measured from the biofilm to the solvent. The growth of the biofilm and the solvent-biofilm interaction with the top nutrient feeding condition is simulated in the viscous regime (growth regime) of the biofilm-solvent mixture flow. In quiescent flows, the model predicts growth patterns consistent with experimental findings for single or multiple adjacent biofilm colonies, in which the known mushroom shape growth pattern is obtained. Shear induced deformation in biofilms is simulated in a shear cell, providing a viable numerical evidence for using simulation tool to study biofilm growth and interaction dynamics in aqueous environment.