Internal fit of two all-ceramic systems and metal-ceramic crowns

OBJECTIVES: The aim of this study was to investigate the internal fit (IF) of glass-infiltrated alumina (ICA - In-Ceram Alumina), yttria-stabilized tetragonal zirconia polycrystals (Y-TZP - IPS e.max ZirCAD), and metal-ceramic (MC - Ni-Cr alloy) crowns. MATERIAL AND METHODS: Sixty standardized resin-tooth replicas of a maxillary first molar were produced for crown placement and divided into 3 groups (n=20 each) according to the core material used (metal, ICA or Y-TZP). The IF of the crowns was measured using the replica technique, which employs a light body polyvinyl siloxane impression material to simulate the cement layer thickness. The data were analyzed according to the surfaces obtained for the occlusal space (OS), axial space (AS) and total mean (TM) using two-way ANOVA with Tukey s multiple comparison test (p<0.05). RESULTS: No differences among the different areas were detected in the MC group. For the Y-TZP and ICA groups, AS was statistically lower than both OS and TM. No differences in AS were observed among the groups. However, OS and TM showed significantly higher values for ICA and Y-TZP groups than MC group. Comparisons of ICA and Y-TZP revealed that OS was significantly lower for Y-TZP group, whereas no differences were observed for TM. CONCLUSIONS: The total mean achieved by all groups was within the range of clinical acceptability. However, the metal-ceramic group demonstrated significantly lower values than the all-ceramic groups, especially in OS.

Breeze-forced oscillations and strongly nonlinear tide-generated internal solitons

Programa de doctorado en Oceanografía

Dynamics of the Gulf of California (GC). A case study of the internal waves using synthetic aperture radar (SAR)

Calificación: Matrícula de Honor

Kinematic internal forces in deep foundations with inclined piles

[EN] This paper presents a parametric study that looks into the influence of pile rake angle on the kinematic internal forces of deep foundations with inclined piles. Envelopes of maximum kinematic bending moments, shear forces and axial loads are presented along single inclined piles and 2X2 symmetrial square pile groups with inclined elements subjected to an earthquake generated by vertically-incident shear waves.

Internal Model Principle: extension to the switching case and applications

This thesis deals with a novel control approach based on the extension of the well-known Internal Model Principle to the case of periodic switched linear exosystems. This extension, inspired by power electronics applications, aims to provide an effective design method to robustly achieve the asymptotic tracking of periodic references with an infinite number of harmonics. In the first part of the thesis the basic components of the novel control scheme are described and preliminary results on stabilization are provided. In the second part, advanced control methods for two applications coming from the world high energy physics are presented.

Sedimentary rocks of the Internal Hellenides, Greece: age, source, and depositional setting

Ziel der vorliegenden Dissertation war die Untersuchung der Liefergebiete und Ablagerungsräume sedimentärer Gesteine aus ausgewählten Gebieten der inneren Helleniden Griechenlands. Die untersuchten Sedimente Nordgriechenlands gehören zu den Pirgadikia und Vertiskos Einheiten des Serbo-Makedonische Massifs, zu den Examili, Melissochori und Prinochori Formationen der östlichen Vardar Zone und zur Makri Einheit und Melia Formation des östlichen Zirkum-Rhodope-Gürtels in Thrakien. In der östlichen Ägäis lag der Schwerpunkt bei den Sedimenten der Insel Chios. Der Metamorphosegrad der untersuchten Gesteine variiert von der untersten Grünschieferfazies bis hin zur Amphibolitfazies. Das stratigraphische Alter reicht vom Ordovizium bis zur Kreide. Zur Charakterisierung der Gesteine und ihrer Liefgebiete wurden Haupt- und Spurenelementgehalte der Gesamtgesteine bestimmt, mineralchemische Analysen durchgeführt und detritische Zirkone mit U–Pb datiert. An ausgewählten Proben wurden außerdem biostratigraphische Untersuchungen zur Bestimmung des Sedimentationsalters durchgeführt. Die Untersuchungsergebnisse dieser Arbeit sind von großer Bedeutung für paläogeographische Rekonstruktionen der Tethys. Die wichtigsten Ergebnisse lassen sich wie folgt zusammenfassen: Die ältesten Sedimente Nordgriechenlands gehören zur Pirgadikia Einheit des Serbo-Makedonischen Massifs. Es sind sehr reife, quarzreiche, siliziklastische Metasedimente, die auf Grund ihrer Maturität und ihrer detritischen Zirkone mit ordovizischen overlap-Sequenzen vom Nordrand Gondwanas korreliert werden können. Die Metasedimente der Vertiskos Einheit besitzen ein ähnliches stratigraphisches Alter, haben aber einen anderen Ablagerungsraum. Das Altersspektrum detritischer Zirkone lässt auf ein Liefergebiet im Raum NW Afrikas (Hun Superterrane) schließen. Die Gesteinsassoziation der Vertiskos Einheit wird als Teil einer aktiven Kontinentalrandabfolge gesehen. Die ältesten biostratigraphisch datierten Sedimente Griechenlands sind silurische bis karbonische Olistolithe aus einer spätpaläozoischen Turbidit-Olistostrom Einheit auf der Insel Chios. Die Alter detritischer Zirkone und die Liefergebietsanalyse der fossilführenden Olistolithe lassen den Schluss zu, dass die klastischen Sedimente von Chios Material vom Sakarya Mikrokontinent in der West-Türkei und faziellen Äquivalenten zu paläozoischen Gesteinen der Istanbul Zone in der Nord-Türkei und der Balkan Region erhalten haben. Während der Permotrias wurde die Examili Formation der östlichen Vardar Zone in einem intrakontinentalen, sedimentären Becken, nahe der Vertiskos Einheit abgelagert. Untergeordnet wurde auch karbonisches Grundgebirgsmaterial eingetragen. Im frühen bis mittleren Jura wurde die Melissochori Formation der östlichen Vardar Zone am Abhang eines karbonatführenden Kontinentalrandes abgelagert. Der Großteil des detritischen Materials kam von permokarbonischem Grundgebirge vulkanischen Ursprungs, vermutlich von der Pelagonischen Zone und/oder der unteren tektonischen Einheit des Rhodope Massifs. Die Makri Einheit in Thrakien besitzt vermutlich ein ähnliches Alter wie die Melissochori Formation. Beide sedimentären Abfolgen ähneln sich sehr. Der Großteil des detritischen Materials für die Makri Einheit kam vom Grundgebirge der Pelagonischen Zone oder äquivalenten Gesteinen. Während der frühen Kreide wurde die Prinochori Formation der östlichen Vardar Zone im Vorfeld eines heterogenen Deckenstapels abgelagert, der ophiolitisches Material sowie Grundgebirge ähnlich zu dem der Vertiskos Einheit enthielt. Ebenfalls während der Kreidezeit wurde in Thrakien, vermutlich im Vorfeld eines metamorphen Deckenstapels mit Affinitäten zum Grundgebirge der Rhodopen die Melia Formation abgelagert. Zusammenfassend kann festgehalten werden, dass die Subduktion eines Teiles der Paläotethys und die anschließende Akkretion vom Nordrand Gondwanas stammender Mikrokontinente (Terranes) nahe dem südlichen aktiven Kontinentalrand Eurasiens den geodynamischen Rahmen für die Schüttung des detritischen Materials der Sedimente der inneren Helleniden im späten Paläozoikum bildeten. Die darauf folgenden frühmesozoischen Riftprozesse leiteten die Bildung von Ozeanbecken der Neotethys ein. Intraozeanische Subduktion und die Obduzierung von Ophioliten prägten die Zeit des Jura. Die spätjurassische und frühkretazische tektonische Phase wurde durch die Ablagerung von mittelkretazischen Kalksteinen besiegelt. Die endgültige Schließung von Ozeanbecken der Neotethys im Bereich der inneren Helleniden erfolgte schließlich in der späten Kreide und im Tertiär.

Total internal reflection fluorescence cross-correlation spectroscopy: theory and application for studying boundary slip phenomenon

I present a new experimental method called Total Internal Reflection Fluorescence Cross-Correlation Spectroscopy (TIR-FCCS). It is a method that can probe hydrodynamic flows near solid surfaces, on length scales of tens of nanometres. Fluorescent tracers flowing with the liquid are excited by evanescent light, produced by epi-illumination through the periphery of a high NA oil-immersion objective. Due to the fast decay of the evanescent wave, fluorescence only occurs for tracers in the ~100 nm proximity of the surface, thus resulting in very high normal resolution. The time-resolved fluorescence intensity signals from two laterally shifted (in flow direction) observation volumes, created by two confocal pinholes are independently measured and recorded. The cross-correlation of these signals provides important information for the tracers’ motion and thus their flow velocity. Due to the high sensitivity of the method, fluorescent species with different size, down to single dye molecules can be used as tracers. The aim of my work was to build an experimental setup for TIR-FCCS and use it to experimentally measure the shear rate and slip length of water flowing on hydrophilic and hydrophobic surfaces. However, in order to extract these parameters from the measured correlation curves a quantitative data analysis is needed. This is not straightforward task due to the complexity of the problem, which makes the derivation of analytical expressions for the correlation functions needed to fit the experimental data, impossible. Therefore in order to process and interpret the experimental results I also describe a new numerical method of data analysis of the acquired auto- and cross-correlation curves – Brownian Dynamics techniques are used to produce simulated auto- and cross-correlation functions and to fit the corresponding experimental data. I show how to combine detailed and fairly realistic theoretical modelling of the phenomena with accurate measurements of the correlation functions, in order to establish a fully quantitative method to retrieve the flow properties from the experiments. An importance-sampling Monte Carlo procedure is employed in order to fit the experiments. This provides the optimum parameter values together with their statistical error bars. The approach is well suited for both modern desktop PC machines and massively parallel computers. The latter allows making the data analysis within short computing times. I applied this method to study flow of aqueous electrolyte solution near smooth hydrophilic and hydrophobic surfaces. Generally on hydrophilic surface slip is not expected, while on hydrophobic surface some slippage may exists. Our results show that on both hydrophilic and moderately hydrophobic (contact angle ~85°) surfaces the slip length is ~10-15nm or lower, and within the limitations of the experiments and the model, indistinguishable from zero.

Understanding the Combined Role of Internal and External Factors in New Service Development Process within the Professional Knowledge Intensive Business Service Firms

Our research asked the following main questions: how the characteristics of professionals service firms allow them to successfully innovate in exploiting through exploring by combining internal and external factors of innovation and how these ambidextrous organisations perceive these factors; and how do successful innovators in professional service firms use corporate entrepreneurship models in their new service development processes? With a goal to shed light on innovation in professional knowledge intensive business service firms’ (PKIBS), we concluded a qualitative analysis of ten globally acting law firms, providing business legal services. We analyse the internal and factors of innovation that are critical for PKIBS’ innovation. We suggest how these firms become ambidextrous in changing environment. Our findings show that this kind of firms has particular type of ambidexterity due to their specific characteristics. As PKIBS are very dependant on its human capital, governance structure, and the high expectations of their clients, their ambidexterity is structural, but also contextual at the same time. In addition, we suggest 3 types of corporate entrepreneurship models that international PKIBS use to enhance innovation in turbulent environments. We looked at how law firms going through turbulent environments were using corporate entrepreneurship activities as a part of their strategies to be more innovative. Using visual mapping methodology, we developed three types of innovation patterns in the law firms. We suggest that corporate entrepreneurship models depend on successful application of mainly three elements: who participates in corporate entrepreneurship initiatives; what are the formal processes that enhances these initiatives; and what are the policies applied to this type of behaviour.

Internal characteristics, chemical compounds and spectroscopy of sapphire as single crystals

In this study more than 450 natural sapphire samples (most of basaltic type) collected from 19 different areas were examined. They are from Dak Nong, Dak Lak, Quy Chau, two unknown sources from the north (Vietnam); Bo Ploi, Khao Ploi Waen (Thailand); Ban Huay Sai (Laos); Australia; Shandong (China); Andapa, Antsirabe, Nosibe (Madagascar); Ballapana (Sri Lanka); Brazil; Russia; Colombia; Tansania and Malawi. rnThe samples were studied on internal characteristics, chemical compositions, Raman-, luminescence-, Fourier transform infrared (FTIR)-, and ultraviolet-visible-near infrared (UV-Vis-NIR)- spectroscopy. The internal features of these sapphire samples were observed and identified by gemological microscope, con focal micro Raman and FTIR spectroscopy. The major and minor elements of the samples were determined by electron probe microanalysis (EPMA) and the trace elements by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). rnThe structural spectra of sapphire were investigated by con focal Raman spectroscopy. The FTIR spectroscopy was used to study the vibration modes of OH-groups and also to determine hydrous mineral inclusions in sapphire. The UV-Vis-NIR absorption spectroscopy was used to analyze the cause of sapphire color. rnNatural sapphires contain many types of mineral inclusions. Typically, they are iron-containing inclusions like goethite, ilmenite, hematite, magnetite or silicate minerals commonly feldspar, and often observed in sapphires from Asia countries, like Dak Nong, Dak Lak in the south of Vietnam, Ban Huay Sai (Laos), Khao Ploi Waen and Bo Ploi (Thailand) or Shandong (China). Meanwhile, CO2-diaspore inclusions are normally found in sapphires from Tansania, Colombia, or the north of Vietnam like Quy Chau. rnIron is the most dominant element in sapphire, up to 1.95 wt.% Fe2O3 measured by EPMA and it affects spectral characteristics of sapphire.rnThe Raman spectra of sapphire contain seven peaks (2A1g + 5Eg). Two peaks at about 418.3 cm-1 and 577.7 cm-1 are influenced by high iron content. These two peaks shift towards smaller wavenumbers corresponding to increasing iron content. This shift is showed by two equations y(418.3)=418.29-0.53x andy(577.7)=577.96-0.75x, in which y is peak position (cm-1) and x is Fe2O3 content (wt.%). By exploiting two these equations one can estimate the Fe2O3 contents of sapphire or corundum by identifying the respective Raman peak positions. Determining the Fe2O3 content in sapphire can help to distinguish sapphires from different origins, e.g. magmatic and metamorphic sapphire. rnThe luminescence of sapphire is characterized by two R-lines: R1 at about 694 nm and R2 at about 692 nm. This characteristic is also influenced by high iron content. The peak positions of two R-lines shift towards to smaller wavelengths corresponding to increasing of iron content. This correlation is showed by two equations y(R_2 )=692.86-0.049x and y(R_1 )=694.29-0.047x, in which y is peak position (nm) of respective R-lines and x is Fe2O3 content (wt.%). Two these equations can be applied to estimate the Fe2O3 content of sapphire and help to separate sapphires from different origins. The luminescence is also applied for determination of the remnant pressure or stress around inclusions in Cr3+-containing corundum by calibrating a 0-pressure position in experimental techniques.rnThe infrared spectra show the presence of vibrations originating from OH-groups and hydrous mineral inclusions in the range of 2500-4000 cm-1. Iron has also an effect upon the main and strongest peak at about 3310 cm-1. The 3310 cm-1 peak is shifted to higher wavenumber when iron content increases. This relationship is expressed by the equation y(3310)=0.92x+3309.17, in which y is peak position of the 3310 cm-1 and x is Fe2O3 content (wt.%). Similar to the obtained results in Raman and luminescence spectra, this expression can be used to estimate the Fe2O3 content and separate sapphires from different origins. rnThe UV-Vis-NIR absorption spectra point out the strong and sharp peaks at about 377, 387, and 450 nm related to dispersed Fe3+, a broad band around 557 and 600 nm related to intervalence charge transfer (IVCT) Fe2+/Ti4+, and a broader band around 863 nm related to IVCT of Fe2+/Fe3+. rnGenerally, sapphires from different localities were completely investigated on internal features, chemical compounds, and solid spectral characteristics. The results in each part contribute for identifying the iron content and separate sapphires from different localities order origins. rn

An examination chair to measure internal rotation of the hip in routine settings: a validation study

OBJECTIVE: To determine the performance of a newly developed examination chair as compared with the clinical standard of assessing internal rotation (IR) of the flexed hip with a goniometer. METHODS: The examination chair allowed measurement of IR in a sitting position simultaneously in both hips, with hips and knees flexed 90 degrees, lower legs hanging unsupported and a standardized load of 5 kg applied to both ankles using a bilateral pulley system. Clinical assessment of IR was performed in supine position with hips and knees flexed 90 degrees using a goniometer. Within the framework of a population-based inception cohort study, we calculated inter-observer agreement in two samples of 84 and 64 consecutive, unselected young asymptomatic males using intra-class correlation coefficients (ICC) and determined the correlation between IR assessed with examination chair and clinical assessment. RESULTS: Inter-observer agreement was excellent for the examination chair (ICC right hip, 0.92, 95% confidence interval [CI] 0.89-0.95; ICC left hip, 0.90, 95% CI 0.86-0.94), and considerably higher than that seen with clinical assessment (ICC right hip, 0.65, 95% CI 0.49-0.77; ICC left hip, 0.69, 95% CI 0.54-0.80, P for difference in ICC between examination chair and clinical assessment

Internal fixation of symphyseal disruption resulting from childbirth

To investigate the clinical and radiographic results after operative treatment of complete symphyseal disruption resulting from childbirth and to evaluate residual pain and implant failure in relation to the timing of surgery.

Demonstration of pelvic anatomy by modified midline transection that maintains intact internal pelvic organs

Gross dissection for demonstrating anatomy of the human pelvis has traditionally involved one of two approaches, each with advantages and disadvantages. Classic hemisection in the median plane through the pelvic ring transects the visceral organs but maintains two symmetric pelvic halves. An alternative paramedial transection compromises one side of the bony pelvis but leaves the internal organs intact. The authors propose a modified technique that combines advantages of both classical dissections. This novel approach involves dividing the pubic symphysis and sacrum in the median plane after shifting all internal organs to one side. The hemipelvis without internal organs is immediately available for further dissection of the lower limb. The hemipelvis with intact internal organs is ideal for showing the complex spatial relationships of the pelvic organs and vessels relative to the intact pelvic floor.