bluuebunny/crossref_metadata_2025_split huggingface dataset:
Survival of Inlays and Partial Crowns Made of IPS Empress After a 10-year Observation Period and in Relation to Various Treatment Parameters
Authors: Stoll R. , Cappel I. , Jablonski-Momeni A. , Pieper K. , Stachniss V. 
Published: January 2008

Clinical Relevance
Ceramic inlays as aesthetic restorations in the posterior region can be used successfully in routine clinical therapy. Cement viscosity, the operator (experienced dentist vs dental student) and the number of surfaces have no influence on longevity.
Cytotoxicity of Composite Materials Polymerized with LED Curing Units
Authors: Knezevic A. , Zeljezic D. , Kopjar N. , Tarle Z. 
Published: January 2008

Clinical Relevance
Curing light intensity is one of the main parameters for proper resin composite cure. Inadequate polymerization of a composite can be harmful to vital pulp tissue and can compromise the durability and quality of the final restoration.
Fracture Resistance and Gap Formation of MOD Restorations: Influence of Restorative Technique, Bevel Preparation and Water Storage
Authors: Coelho-de-Souza F. H. , Camacho G. B. , Demarco F. F. , Powers J. M. 
Published: January 2008

Clinical Relevance
Beveling of the cavosurface margin can improve resistance to fracture and the marginal adaptation of posterior composite restorations, reducing the deleterious effect of storage with thermal cycling on restoration quality. Generally, indirect restorations showed similar performance compared to direct restorations.
Comparative Clinical Evaluation of Different Treatment Approaches Using a Microfilled Resin Composite and a Compomer in Class III Cavities: Two-year Results
Authors: Demirci M. , Yildiz E. , Uysal Ö 
Published: January 2008

Clinical Relevance
For two years, the three restoration/adhesive combinations used in this study (Dyract AP/Prime & Bond NT with NRC pretreatment, Dyract AP/Prime & Bond NT with phosphoric acid pretreatment and Filtek A110/Single Bond) exhibited very good clinical performance in Class III cavities. Clinically simplified systems and handling characteristics of materials may effect their clinical performance.
Durability of Enamel Bonding Using Two-step Self-etch Systems on Ground and Unground Enamel
Authors: Loguercio A. D. , Moura S. K. , Pellizzaro A. , Dal-Bianco K. , Patzlaff R. T. , Grande R. H. M. , Reis A. 
Published: January 2008

Clinical Relevance
The effect of surface preparation was adhesive-dependent. Improvements in resin-enamel bond strength after enamel preparation were observed only for AdheSE and Optibond Solo plus Self-Etch Primer. Among the self-etch systems, mild, self-etch Clearfil SE Bond showed the highest bond strength values. No degradation of resin-enamel bonds was observed after 12 months of water storage, regardless of the adhesive tested.
Structure optimisation of short-wavelength ridge-waveguide InGaN/GaN diode lasers
Authors: Karbownik P. , Sarzała R. 
Published: January 2008

AbstractRoom-temperature (RT) continuous-wave (CW) operation of the 405-nm ridge-waveguide (RW) InGaN/GaN quantum-well diode lasers equipped with the n-type GaN substrate and two contacts on both sides of the structure has been investigated with the aid of the comprehensive self-consistent simulation model. As expected, the mounting configuration (p-side up or down) has been found to have a crucial impact on the diode laser performance. For the RT CW threshold operation of the otherwise identical diode laser, the p-side up RW laser exhibits as high as nearly 68°C maximal active-region temperature increase whereas an analogous increase for the p-side down laser was equal to only 24°C. Our simulation reveals that the lowest room-temperature lasing threshold may be expected for relatively narrow and deep ridges. For the structure under consideration, the lowest threshold current density of 5.75 kA/cm2 has been determined for the 2.2-μm ridge width and the 400-nm etching depth. Then, the active-region temperature increase was as low as only 24 K over RT. For wider 5-μm ridge, this increase is twice higher. An impact of etching depth is more essential for narrower ridges. Quite high values (between 120 and 140 K) of the characteristic parameter T0 convince very good thermal properties of the above laser.
Gold-enhanced oxidation of silicon nanowires
Authors: Werner Peter , Büttner Claudia C. , Schubert Luise , Gerth Gerhard , Zakarov Nikolai D. , Gösele Ulrich 
Published: January 2008

Abstract
Silicon nanowires are frequently grown involving a liquid gold droplet at their tips. Here we show that under certain circumstances the thermal oxidation of a silicon nanowire is drastically enhanced by the presence of this gold droplet. Such a gold-enhanced oxidation was observed in a temperature range from 1000 °C down to 250 °C. As a consequence, instead of the slow radial oxidation expected and desired for thinning the nanowires, a fast axial oxidation may occur catalyzed by the gold tip. This leads to a shrinking of the length of the Si nanowire and its replacement by a longer nanowire consisting of silicon dioxide. During this gold-enhanced oxidation process the gold droplet migrates from the tip to the base of the nanowire. Our experiments demonstrate that gold droplets lead to an enhanced dissolution of silicon during oxidation in the case that these remain in intimate contact with the Si nanowires.
Compressive deformation of lamellar microstructures – a short review
Authors: Fischer Franz Dieter , Clemens Helmut , Schaden Thomas , Appel Fritz 
Published: January 2008

Abstract
This paper reviews the essential results of our research on the deformation behavior of fully lamellar microstructures under compressive loading. The most important outcomes, experimentally and theoreticaly, are presented. Usually such fully lamellar microstructures are present in cast intermetallic γ(TiAl)-based alloys; therefore, this class of materials was selected to verify the developed model. During large compressive deformation of γ(TiAl)-based alloys at elevated temperatures the lamellar colonies, depending on their orientation, are often bent or buckled which is representative of a deformation “instability” characterized by a large wave length. Structural defects of the lamellae as well as their somewhat irregular arrangement trigger such a deformation behavior. In addition, kink formation and shear band-type deformation modes occur according to an “instability” mode exhibiting a short wave length. These two deformation modes interact in a rather subtle way, which leads to a very inhomogeneous deformation pattern. A short paragraph on the stability behavior of composites is, therefore, added.
Experimental studies and thermodynamic simulation of phase transformations in high Nb containing γ-TiAl based alloys
Authors: Chladil Harald F. , Clemens Helmut , Zickler Gerald A. , Takeyama Masao , Kozeschnik Ernst , Bartels Arno , Buslaps Thomas , Gerling Rainer , Kremmer Sascha , Yeoh LaReine , Liss Klaus-Dieter 
Published: January 2008

Abstract
Solid-state phase transformations and phase transition temperatures in Ti-45 at.% Al and Ti-45 at.% Al-(5, 7.5, 10) at.% Nb alloys were analyzed experimentally and compared to thermodynamic calculations. Results from scanning electron microscopy, high-energy and conventional X-ray diffraction as well as differential scanning calorimetry were used for the characterization of the prevailing phases and phase transformations. For the prediction of phase stabilities and phase transition temperatures, thermodynamic calculations using the CALPHAD method were conducted. In order to achieve better agreement between calculated and experimental results, a commercially available database was modified using our own results from thermo-physical measurements and annealing treatments.
Enhanced thermal stability of a cobalt–boron carbide nanocomposite by ion-implantation
Authors: daSilva Melina , Klement Uta , Hibbard Glenn D. 
Published: January 2008

Abstract
A first investigation of the thermal stability in a wear resistant cobalt-boron carbide (Co – B4C) nanocomposite has been performed by the combination of calorimetry and transmission electron microscopy. The calorimetric measurements show that the thermal stability of Co – B4C is not influenced by the presence of the 10 vol.% μm-sized boron carbide particles. However, grain growth is shifted to significantly higher temperatures during in-situ annealing (in the transmission electron microscope), and abnormal grain growth is not observed to be as extensive as in conventional nanocrystalline Co. This effect is mainly attributed to the observed implantation of Ga atoms during transmission electron microscope specimen thinning by focused ion beam. Grain boundary segregation mechanisms are discussed as possible reasons for the retarded grain growth.
Development of the unloading stiffness during cyclic plastic deformation of a high-strength aluminium alloy in different tempers
Authors: Hörnqvist Magnus , Karlsson Birger 
Published: January 2008

AbstractThe development of stiffness during unloading from peak stress during cyclic plastic deformation (low cycle fatigue) was studied in a high-strength Al-5.4Zn-1.2Mg alloy, both in naturally aged and peak aged conditions. A phenomenological model based on a order stress – strain relationship was developed using data from detailed recordings of the stress–strain hysteresis loops. Three stages of the parameter values were identified: an initial transition part of the fatigue life time, a major stationary stage shifting over to the final stage where failure modes become prominent. The nonlinear stiffness was found to be asymmetric with respect to tension and compression. Further, the naturally aged material generally shows larger stiffness for both positive and negative stresses than does the peak aged material. Finally, the stiffness for the naturally aged condition exhibits larger scatter compared to the peak aged materials, interpreted as inferior averaging in the dislocation structures.
Numerical determination of parameterised failure curves for ductile structural materials
Authors: Weber Ulrich , Mohanta Ashok , Schmauder Siegfried 
Published: January 2008

Abstract
Inhomogeneities such as voids or inclusions can lead to stress and strain concentrations under external loading conditions due to the different elastic – plastic and thermal properties of the phases. To describe the damage behavior of ductile materials, a damage parameter was introduced by Rice and Tracey and so-called failure curves (determined by experiments) describe different possible stress – strain states at fracture. The experimental effort can be reduced by applying unit cell models consisting of a single void in the base material with a pre-defined void volume fraction f0. With these models, stress triaxialities and plastic strains are calculated and failure curves are derived. Parameter studies are performed to obtain analytical equations for the material dependent constants A and B as a function of the initial void volume fraction f0 and the hardening exponent N as well as the yield stress 0.
Sandwich panels for blast protection in water: simulations
Authors: Spuskanyuk Alexander V. , McMeeking Robert M. 
Published: January 2008

Abstract
Edge supported metallic sandwich panels subject to underwater blast respond in a manner dependent on the relative timescales for water cavitation, core crushing, and structural response in bending. This article examines the response to impulses representative of an (especially relevant) domain: wherein the water cavitates before the core crushes. In some cases, core crushing ceases before the overall structural deformation is complete, leading to what is termed strong-core response. In other situations, core crushing continues beyond the stage at which the dry-face of the sandwich panel ceases to deform, a behavior that is known as weak-core response. It is known that weak-core response provides superior panel performance in terms of three performance metrics: the back-face deflection, the tearing susceptibility of the faces and the loads transmitted to the supports. The relevant regime of behavior is determined by the magnitude of the transmitted impulse from the water, the relative strength of the core, and the aspect ratio of the panel, so that a panel must be designed carefully against a known threat to achieve optimal performance. This paper initiates the development of a map of response for sandwich panels having I-core geometry, delineating strong, weak and other behavior in terms of some of the design parameters mentioned above. The effect of fluid – structure interaction is included in the simulations, and these results are contrasted with those in which fluid – structure interaction is omitted and an initial impulse is instead given to the wet-face of the panel.
In-situ studies of the TGO growth stresses and the martensitic transformation in the B2 phase in commercial Pt-modified NiAl and NiCoCrAlY bond coat alloys
Authors: Hovis D. , Hu L. , Reddy A. , Heuer A. H. , Paulikas A. P. , Veal B. W. 
Published: January 2008

Abstract
Oxide growth stresses were measured in situ at 1100 °C on commercial Pt-modified NiAl and NiCoCrAlY bond coat alloys using synchrotron X-rays. Measurements were taken on samples that had no preoxidation, as well as on samples that had experienced 24 one-hour thermal exposures at 1150 °C, a condition known to induce rumpling in the Pt-modified NiAl alloy, but not in the NiCoCrAlY alloy. The NiCoCrAlY alloy showed continuous stress relaxation under all conditions, whereas the Pt-modified NiAl alloys would typically stabilize at a fixed (often non-zero) stress suggesting a higher creep strength in the “Thermally Grown Oxide” on the latter alloy, though the precise behavior was dependent on initial surface preparation. The formation of martensite in the Pt-modified NiAl alloys was also observed upon cooling and occurred at temperatures below 200 °C for all of the samples observed. Based on existing models, this M
s temperature is too low to account for the rumpling observed in these alloys.
High temperature creep of La-monazite
Authors: Berbon M. , Davis J. B. , Marshall D. B. , Housley R. M. , Morgan P. E. D. 
Published: January 2008

AbstractCompressive creep of La-monazite is investigated in the temperature range 1100 °C to 1500 °C. The study includes both high-purity single-phase material and material with excess phosphorus located in amorphous grain boundary phases. The results indicate that the presence of small amounts of excess P in polycrystalline LaPO4has a large effect on microstructural stability and creep at high temperature. Materials with La/P ratio close to unity (within ∼500 ppm) show little grain growth at temperatures up to 1400 °C and deform by creep at rates similar to those of alumina and zirconia, with stress exponent ∼1. Materials containing excess P (as little as ∼1 %) show more rapid grain growth, higher creep rates, and cavitation during creep. The results are compared with creep rates of other refractory oxides and oxide fibers. Implications for the behavior of oxide composites containing La-monazite are considered.
Thermal-elastic response of marble polycrystals: Influence of grain orientation configuration
Authors: Saylor David M. , Fuller Edwin R. , Weiss Thomas 
Published: January 2008

AbstractTwo-dimensional, microstructure-based finite element simulations were used to elucidate the influence of grain orientation configuration on the thermal-elastic response of polycrystalline ceramic materials. The two main constituent minerals of marbles, calcite and dolomite, were considered. The crystallographic configuration of the grains is described in terms of the distribution of grain orientations and grain-boundary misorientations. To probe the influence of grain orientation configuration, we first generated the geometry of a hypothetical microstructure. Next, crystallographic orientations were assigned to each grain in the microstructure such that the grain orientations and grain-boundary misorientations matched predefined distributions. By varying the predefined distributions, we generated 45 unique microstructures covering a wide range of crystallographic configurations. After assigning thermal-elastic properties to each structure, corresponding to either calcite or dolomite, finite-element simulations were performed. The simulations demonstrated that both the orientation and misorientation distributions have a substantial impact on the thermal-elastic response of microstructures with the same material properties: varying the crystallographic configuration results in variations of stored elastic strain energy density from 10 kJ m−3to 39 kJ m−3for a 100 °C temperature change. Further, the ratio of the bulk coefficient of thermal expansion in the two principal directions varies from − 0.17 to 1.46. Surprisingly, the grain-boundary misorientations alone had a substantial impact on the thermal-elastic response of the system. By simply rearranging a fixed set of crystallographic orientations to obtain different nearest-neighbor misorientation configurations, we observed variations in strain energy density from 10 kJ m−3to 39 kJ m−3and variations in thermal expansion ratio from 0.06 to 0.90. The results suggest that to predict accurately the thermal-elastic response of polycrystalline ceramics, it is critical to consider both the distribution of grain-boundary misorientations as well as the distribution of grain orientations.
Adhesion of the γ-Ni(Al)/α-Al2O3 interface: a first-principles assessment
Authors: Smith John R. , Jiang Yong , Evans Anthony G. 
Published: January 2008

Abstract
We assess density functional theory studies of the effects of interfacial stoichiometry, Al activity, S segregation and Hf doping on the adhesion of the γ-Ni(Al)/α-Al2O3 interface. Computations of the Al activity in γ-Ni(Al) and of the interfacial phase diagram between 1300 and 1600 K suggest that the interface phase is Al-rich, but close to the boundary with the stoichiometric phase. We reveal that the Al-rich phase has significantly stronger adhesion than the stoichiometric phase and that S substantially decreases the adhesion of both. We demonstrate that doping with Hf yields a substantial improvement in adhesion, manifest in three ways: (i) It can pin S in bulk γ-Ni(Al), even up to 1600 K. (ii) It segregates and, once there, can strengthen the relatively weak stoichiometric interface (attaining a work of separation comparable to that for the strong Al-rich interface). (iii) It has the potential to displace S from interstitial interface sites.
Phase stability of thermal barrier oxides: A comparative study of Y and Yb additions
Authors: Cairney Julie M. , Rebollo Noemi R. , Rühle Manfred , Levi Carlos G. 
Published: January 2008

AbstractThe maximum operating temperature of conventional thermal barrier coatings based on yttria-stabilized zirconia is ultimately limited by de-stabilization of the “non-transformable” t phase, rendering it susceptible to the monoclinic transformation upon cooling. Investigations into alternative thermal barrier oxide compositions suggest that Yb offers superior t stability compared with Y, Sc and larger rare earth cations at the same concentration. The present study sheds light on this behavior by comparing the microstructure evolution of specimens with 7.6 and 11.4 % MO1.5(M = Y or Yb) heat treated at 1450 °C for times up to 512 h. X-ray diffractometry and transmission electron microscopy revealed that the onset of partitioning occurs at short times but then the compositions of the phases evolve slowly over time until sufficient stabilizer is depleted from the t phase to render it transformable. Substitution of Yb for Y delays the onset of monoclinic formation. Differences in the transformation behavior of the Y and Yb rich phases on cooling provide new insight and suggest refinements to the current thermodynamic models for the binary ZrO2– MO1.5systems are needed.
Automated Text Message–Based Program and Use of Acute Health Care Resources After Hospital Discharge
Authors: Bressman Eric , Long Judith A. , Burke Robert E. , Ahn Aiden , Honig Katherine , Zee Jarcy , McGlaughlin Nancy , Balachandran Mohan , Asch David A. , Morgan Anna U. 
Published: April 2024

ImportancePostdischarge outreach from the primary care practice is an important component of transitional care support. The most common method of contact is via telephone call, but calls are labor intensive and therefore limited in scope.ObjectiveTo test whether a 30-day automated texting program to support primary care patients after hospital discharge reduces acute care revisits.Design, Setting, and ParticipantsA 2-arm randomized clinical trial was conducted from March 29, 2022, through January 5, 2023, at 30 primary care practices within a single academic health system in Philadelphia, Pennsylvania. Patients were followed up for 60 days after discharge. Investigators were blinded to assignment, but patients and practice staff were not. Participants included established patients of the study practices who were aged 18 years or older, discharged from an acute care hospitalization, and considered medium to high risk for adverse health events by a health system risk score. All analyses were conducted using an intention-to-treat approach.InterventionPatients in the intervention group received automated check-in text messages from their primary care practice on a tapering schedule for 30 days following discharge. Any needs identified by the automated messaging platform were escalated to practice staff for follow-up via an electronic medical record inbox. Patients in the control group received a standard transitional care management telephone call from their practice within 2 business days of discharge.Main Outcomes and MeasuresThe primary study outcome was any acute care revisit (readmission or emergency department visit) within 30 days of discharge.ResultsOf the 4736 participants, 2824 (59.6%) were female; the mean (SD) age was 65.4 (16.5) years. The mean (SD) length of index hospital stay was 5.5 (7.9) days. A total of 2352 patients were randomized to the intervention arm and 2384 were randomized to the control arm. There were 557 (23.4%) acute care revisits in the control group and 561 (23.9%) in the intervention group within 30 days of discharge (risk ratio, 1.02; 95% CI, 0.92-1.13). Among the patients in the intervention arm, 79.5% answered at least 1 message and 41.9% had at least 1 need identified.Conclusions and RelevanceIn this randomized clinical trial of a 30-day postdischarge automated texting program, there was no significant reduction in acute care revisits.Trial RegistrationClinicalTrials.gov Identifier: NCT05245773
7T MRI detects widespread brain iron deposition in neuroferritinopathy
Authors: Murley Alexander G. , Rua Catarina , Biggs Heather , Rodgers Christopher T. , Matys Tomasz , van den Ameele Jelle , Horvath Rita , Chinnery Patrick F. 
Published: April 2024

AbstractNeuroferritinopathy is a disorder of neurodegeneration with brain iron accumulation that has no proven disease‐modifying treatments. Clinical trials require biomarkers of iron deposition. We examined brain iron accumulation in one presymptomatic FTL mutation carrier, two individuals with neuroferritinopathy and one healthy control using ultra‐high‐field 7T MRI. There was increased magnetic susceptibility, suggestive of iron deposition, in superficial and deep gray matter in both presymptomatic and symptomatic neuroferritinopathy. Cavitation of the putamen and globus pallidus increased with disease stage and at follow up. The widespread brain iron deposition in presymptomatic and early disease provides an opportunity for monitoring disease‐modifying intervention.