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PROCEEDINGS, GEOFLUIDS VII ¿ International Conference IFP Energies nouvelles, Rueil-Malmaison (France), June 6-8, 2012 ; The Vilobí Gypsum Unit (upper Burdigalian) is located in the Penedès Half-graben (northeast of the Iberian Peninsula). This unit consists of a succession of secondary (predominant, coming from hydration of anhydrite) and primary (limited to the top interval) laminated-to-banded gypsum and laminated lutites-carbonates. This succession is affected by 5 fractures sets due to the fragile deformation related to the Neogene extensional stages recorded in the region. These fragile structures are partly or totally cemented by four gypsum cements types (fibrous, millimetrical crystals, aligned and macrocrystalline gypsum), resulting from fluid circulation along the fractures. A successive isotopic enrichment (¿34SVCDT, ¿18OVSMOW) from the host-gypsum rocks and the different fracture infillings is evidenced, thus suggesting chemical recycling processes. The strontium ratios of gypsum cements suggest higher fluid interaction during the macrocrystalline cements precipitation, with respect to the fibrous infillings. ; Financial support by the I+D+I Spanish Government research projects CGL2010-18260, CGL2009-11096 and Grup Consolidat de Recerca "Geologia Sedimentària" (2009 SGR-1458).

A three-dimensional absolute profile parameter was used to characterize the height irregularities of the fracture surfaces of cement pastes. The dependence of these irregularities on porosity was studied and its non-linear character was proved. An analytical form for the detected non-linearity was suggested and then experimentally tested. The surface irregularities manifest scale-invariance properties.

. Seventy-eight graphs were plotted to describe and analyze the dependences of the height and roughness irregularities on the water-to-cement ratio and on the porosity of the cement hydrates. The results showed unambiguously that the water-to-cement ratio or equivalently the porosity of the specimens has a decisive influence on the irregularities of the fracture surfaces of this material. The experimental results indicated the possibility that the porosity or the value of the water-to-cement ratio might be inferred from the height irregularities of the fracture surfaces. It was hypothesized that there may be a similarly strong correlation between porosity and surface irregularity, on the one hand, and some other highly porous solids, on the other, and thus the same possibility to infer porosity from the surfaces of their fracture remnants.

Carbon nanotubes (CNT) are an attractive reinforcement material for several composites, due to their inherently high strength and high modulus of elasticity. There are controversial results for cement paste with admixed CNT up to 500 µm in length. Some results show an increase in flexural or compressive strength, while others showing a decrease in the values. Our experiments produced results that showed a small increase in fracture energy and tensile strength. Micromechanical simulations on a CNT-reinforced cement paste 50×50 µm proved that CNT clustering is the crucial factor for an increasein fracture energy and for an improvement in tensile strength.

The main objective of this article is to present the influence of high temperatures on mechanical properties of advanced refractory cement composite reinforced with carbon fibres. The presented material is suitable for industrial applications and can withstand elevated temperatures up to 1000 °C. The action of high temperatures was investigated on two temperature levels 600 °C and 1000 °C and was compared to reference specimens dried at 105 °C. The carbon fibres with flexural strength of 4100MPa were applied in dosage 0.50 %, 0.75% and 1.00% of the total volume. The second investigated modification was mutual ratio between aluminous cement and fine ceramic powder. The influence of high temperatures was investigated by measuring the bulk density, compressive and flexural strength, dynamic modulus of elasticity and fracture energy; all measured on prismatic specimens 40 × 40 × 160 mm. The workability of fresh mixture was limited by the maximum dosage of carbon fibres in 1% of the total volume. Based on the workability and evaluation of residual mechanical properties after temperature loading, the best was found to be the combination of carbon fibres in dosage of 0.75% by volume.

In 1995, the Swedish government recommended the discontinuation of amalgam as restorative in paediatric dentistry. Because the mercury content in amalgam constitutes an environmental hazard, its use has declined. The use of resin composites is increasing, but the polymerisation shrinkage of the material is still undesirably high, and the handling of uncured resin can cause contact dermatitis. A new restorative material has recently been developed in Sweden as an alternative to amalgam and resin composite: a calcium aluminate cement (CAC). CAC has been marketed as a ceramic direct restorative for posterior restorations (class I, II) and for class V restorations. This thesis evaluates mechanical properties and clinical durability of the calcium aluminate cement when used for class II restorations. Hardness, in vitro wear, flexural strength, flexural modulus, and surface roughness were evaluated. A scanning electron replica method was used for evaluation of the interfacial adaptation to tooth structures in vivo. The durability was studied in a 2-year intra-individually clinical follow-up of class II restorations. Major results and conclusions from the studies are as follows: • The CAC was a relatively hard material, harder than resin-modified glass ionomer cement but within the range of resin composites. The CAC wore less than resin-modified glass ionomer cement but more than resin composite. • Flexural strength of CAC was in the same range as that of zinc phosphate cement and far below that of both resin composite and resin-modified glass ionomer cement. Flexural modulus of CAC was higher than both resin composite and resin-modified glass ionomer cement. The low flexural strength of CAC precludes its use in stress-bearing areas. • Surface roughness of CAC could be decreased by several polishing techniques. • For CAC restorations, interfacial adaptation was higher to dentin but lower to enamel compared with resin composite restorations. Fractures were found perpendicular to the boarders of all CAC restorations and may indicate expansion of the material. • After 2 years of clinical service, the class II CAC restorations showed an unacceptably high failure rate. Material fractures and tooth fractures were the main reasons for failure.

This paper presents a study of the surface height irregularities of cement pastes subjected to fast dynamic fractures. The height irregularities are quantified by the values of the three-dimensional profile parameters. The studied dynamical irregularities show a similar analytical behavior to those obtained by static fractures.

Abstract
Background The global trend toward increased life expectancy because of remarkable improvements in health care quality has drawn increased attention to osteoporotic fractures and degenerative spine diseases. Cement-augmented pedicle screw fixation has been established as the mainstay treatment for patients with poor bone quality. This study aimed to determine the number of patients with cement leakage and pulmonary cement embolism (PCE) as detected on thoracic computed tomography (CT), and to assess the potential risk factors for PCE.
Methods Patients undergoing cement-augmented pedicle screw placement in our institution between May 2008 and December 2020 were included. Data regarding baseline characteristics, complications, and cement leakage rates were collected. Indications for the performance of a postoperative thoracic CT due to the suspicion of PCE were intra- or postoperative complications, or postoperative oxygen supplementation. Moreover, PCE was accidently diagnosed because the thoracic CT was performed for medical reasons other than the suspicion of PCE (tumor staging, severe pneumonia, or exacerbated chronic pulmonary obstructive disease).
Results A total of 104 patients with a mean age of 72.8 years (standard deviation of 6.7) were included. Of 802 screws, 573 were cement augmented. Of the 104 patients, 44 (42.3%) underwent thoracic CT scans to diagnose PCE; additionally, 67 (64.4%) demonstrated cement leakage, of whom 27 developed PCE and 4 were symptomatic. Cement-augmented thoracic screws were a risk factor for PCE (odds ratio: 1.5; 95% confidence interval: 1.2–2.1; p = 0.004).
Conclusions This study showed a high prevalence of cement leakage after cement-augmented pedicle screw insertion, with a relatively frequent incidence of PCE, as tracked by thoracic CT scans. Cement-augmented thoracic screw placement was a unique risk factor for PCE.

Purpose Cement leakage is a typical complication of kyphoplasty for vertebral fractures. It is unclear if cement application intraoperatively can be improved by using other techniques of visualization and which kind of postoperative imaging should be recommended to detect cement extravasation accurately.
Objective To compare the rates of cement leakage detected by intraoperative fluoroscopy, postoperative radiography, and postoperative computed tomography (CT) in a retrospective study.
Patients and Methods The study included 78 patients (60 women and 18 men; 115 vertebral bodies) who were treated with two kinds of kyphoplasty. The patients underwent intraoperative fluoroscopy and postoperative radiography and CT. After surgery, the images were evaluated to compare cement leakage rates and locations in the three visualization techniques. Leakage locations were described as epidural, intradiskal, extravertebral, or intravascular.
Results Compared with CT, intraoperative fluoroscopy regularly detected intradiskal leakage (75%) but had a considerably lower sensitivity for visualizing epidural (21%), extravertebral (31%), and intravascular (51%) cement leakages. A comparison of radiography and CT showed that radiography had a high sensitivity for detecting intradiskal (82%) and intravascular (70%) cement extrusions but a lower sensitivity in identifying epidural (42%) and extravertebral (50%) leaks. Therefore, the CT scan overall was best in detecting location and accuracy.
Conclusion CT detected more cement leaks than any of the other investigated techniques, especially epidural, extravertebral, and intravascular cement leakages. To achieve the best accuracy, only CT provides complete information.

YÖK Tez No: 479351 ; Yüksek Lisans ; Petrol bir enerji kaynağı olarak büyüyen ekonomiler için büyük önem arz etmektedir. Hem petrol ithal eden hem de ihraç eden ülkeler petrolün uluslararasını gündemini yakından takip ederler. Birçok ülke stratejik planlarını bu gündeme göre belirler. Özellikle büyüyen ekonomilere sahip petrol ithal eden ülkeler için dalgalanan petrol fiyatları büyük bir önem arz etmektedir. Büyüyen ekonomi ile artan petrol ihtiyacı ülkeleri petrole daha bağımlı hale getirmektedir. Türkiye de bu ülkeler arasında yer almaktadır. Artan enerji ihtiyacı içinde petrol büyük bir orana sahiptir. Hemen hemen her imalat sanayinde petrol doğrudan ya da dolaylı yoldan kullanılmaktadır. Bu tezde, dalgalanan petrol fiyatlarının Türkiye ekonomisinde önemli bir yere sahip çimento sektörüne olan etkisinin araştırılması amaçlanmıştır. Petrol fiyatlarında zaman zaman büyük oranlarda kırılmalar yaşanmıştır. Bu büyük orandaki kırılmalar sektörlere etkileri daha görünür kılmaktadır. Çimento sektöründe en büyük maliyet kalemi yakıttır ve sektörde kullanılan yakıtın yaklaşık 'i petrokoktur. Çimento sektöründe Kamu Aydınlatma Platformu'nda yer alan çimento şirketlerinin karlılık oranları hesaplanarak yıllara göre petrol fiyatları ile karşılaştırılmıştır. Yapılan analizler ışığında, dalgalanan petrol fiyatlarının çimento sektöründe faaliyet gösteren şirketlerin karlılık oranlarına anlamlı bir etkisi olduğu belirlenmiştir. ; Oil as an energy source is of great importance for growing economies. Countries that both import and export oil follow closely the international agenda of oil. Many countries determine their strategic plans according to this agenda. Fluctuating oil prices are of great importance for countries that import petroleum, especially with growing economies. Increasing oil demand with the growing economy makes countries more dependent on oil. Turkey is one of these countries. In an increasing energy need, the oil has a great percentage. In almost every manufacturing industry, oil is used directly or indirectly. In this thesis, it is aimed to investigate the effect of oil prices on the cement sector, which has an important place in the Turkish economy. Oil prices have been broken in large rate from time to time. This large fracture makes the effects more visible to the sectors. The biggest cost in the cement sector is the fuel and approximately 70% of the fuel used in the sector is petroleum. In the cement sector, profitability ratios of the cement companies in the Public Disclosure Platform were calculated and compared with the oil prices according to years. In the light of the analyzes, fluctuating oil prices were found to have a significant effect on the profitability ratios of companies in the cement sector.

Health political and scientific background Bone graft substitutes are increasingly being used as supplements to standard care or as alternative to bone grafts in the treatment of traumatic fractures. Research questions The efficacy and cost-effectiveness of bone graft substitutes for the treatment of traumatic fractures as well as the ethical, social and legal implications of their use are the main research questions addressed. Methods A systematic literature search was conducted in electronic medical databases (MEDLINE, EMBASE etc.) in December 2009. Randomised controlled trials (RCT), where applicable also containing relevant health economic evaluations and publications addressing the ethical, social and legal aspects of using bone graft substitutes for fracture treatment were included in the analysis. After assessment of study quality the information synthesis of the medical data was performed using metaanalysis, the synthesis of the health economic data was performed descriptively. Results 14 RCT were included in the medical analysis, and two in the heath economic evaluation. No relevant publications on the ethical, social and legal implications of the bone graft substitute use were found. In the RCT on fracture treatment with bone morphogenetic protein-2 (BMP-2) versus standard care without bone grafting (RCT with an elevated high risk of bias) there was a significant difference in favour of BMP-2 for several outcome measures. The RCT of calcium phosphate (CaP) cement and bone marrow-based composite materials versus autogenous bone grafts (RCT with a high risk of bias) revealed significant differences in favour of bone graft substitutes for some outcome measures. Regarding the other bone graft substitutes, almost all comparisons demonstrated no significant difference.The use of BMP-2 in addition to standard care without bone grafting led in the study to increased treatment costs considering all patients with traumatic open fractures. However, cost savings through the additional use of BMP-2 were calculated ...

BACKGROUND: The economic burden of vertebral compression fractures (VCF) caused by osteoporosis was estimated at 37 billion euros in the European Union in 2010. In addition, the incidence is expected to increase by 25% in 2025. The recommendations for the therapy of VCFs (conservative treatment versus cement augmentation procedures) are controversial, what could be partly explained by the lack of standardized outcomes for measuring the success of both treatments. Consensus on outcome parameters may improve the relevance of a study and for further comparisons in meta-analyses. The aim of this study was to analyze outcome measures from frequently cited randomized controlled trials (RCTs) about VCF treatments in order to provide guidance for future studies. MATERIAL AND METHODS: We carried out a systematic search of all implemented databases from 1973 to 2019 using the Web of Science database. The terms "spine" and "random" were used for the search. We included: Level I RCTs, conservative treatment or cement augmentation of osteoporotic vertebral fractures, cited ≥50 times. The outcome parameters of each study were extracted and sorted according to the frequency of use. RESULTS: Nine studies met the inclusion criteria. In total, 23 different outcome parameters were used in the nine analyzed studies. Overall, the five most frequently used outcome parameters (≥ 4 times used) were the visual analogue scale (VAS) for pain (n = 9), European Quality of Life–5 Dimensions (EQ-5D; n = 4) and Roland–Morris Disability Questionnaire (RMDQ, n = 4). CONCLUSION: With our study, we demonstrated that a large inconsistency exists between outcome measures in highly cited Level I studies of VCF treatment. Pain (VAS), followed by HrQoL (EQ-5D) and disability and function (RMDQ), opioid use, and radiological outcome (kyphotic angle, VBH, and new VCFs) were the most commonly used outcome parameters. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12891-021-04305-6.

Fracture pattern development has been a challenging area of research in the Earth sciences for more than 100 years. Much has been learned about the spatial and temporal complexity inherent to these systems, but severe challenges remain. Future advances will require new approaches. Chemical processes play a larger role in openingmode fracture pattern development than has hitherto been appreciated. This review examines relationships between mechanical and geochemical processes that influence the fracture patterns recorded in natural settings. For fractures formed in diagenetic settings (~50 to 200 °C), we review evidence of chemical reactions in fractures and show how a chemical perspective helps solve problems in fracture analysis. We also outline impediments to subsurface pattern measurement and interpretation, assess implications of discoveries in fracture history reconstruction for processbased models, review models of fracture cementation and chemically assisted fracture growth, and discuss promising paths for future work. To accurately predict the mechanical and fluid flow properties of fracture systems, a processesbased approach is needed. Progress is possible using observational, experimental, and modeling approaches that view fracture patterns and properties as the result of coupled mechanical and chemical processes. A critical area is reconstructing patterns through time. Such data sets are essential for developing and testing predictive models. Other topics that need work include models of crystal growth and dissolution rates under geological conditions, cement mechanical effects, and subcritical crack propagation. Advances in machine learning and 3D imaging present opportunities for a mechanistic understanding of fracture formation and development, enabling prediction of spatial and temporal complexity over geologic timescales. Geophysical research with a chemical perspective is needed to correctly identify and interpret fractures from geophysical measurements during site characterization and monitoring of subsurface engineering activities. ; This manuscript resulted from discussions at a workshop sponsored by the U.S. Department of Energy (DOE), Office of Science (SC), Office of Basic Energy Sciences (BES), Chemical Sciences, Geosciences, and Biosciences (CSGB) Division that was held in Leesburg, Virginia, in May 2016. We are grateful to James Rustad for his leadership, contributions to discussions at the workshop, and encouragement and support during the preparation of this review. S. E. L. appreciates support in organizing and conducting the workshop and preparing the paper from Grant DEFG0203ER15430 from the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division. Sandia National Laboratories (SNL) is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE's National Nuclear Security Administration under Contract DENA0003525. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated by Battelle Memorial Institute for the U.S. DOE. Contributions from ORNL, SNL and PNNL are based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division. The views expressed in the article do not necessarily represent the views of the U.S. DOE or the U.S. Government. J. L. U. acknowledges funding by the German Science Foundation Project NE 822/341|UR 64/171. We also value discussions with P. Eichhubl, A. Fall, and J. F. W. Gale, contributions to workshop preparation from R. A. Schultz, and discussion and comments from R. Cygan, S.F. Forstner, Q. Wang, and journal reviewers. No data were used in the preparation of this manuscript. ; Published version

Mesozoic and Neogene carbonates located in the Valencia Trough (offshore Spain, western Mediterranean Sea) are oil reservoirs. This paper investigates the diagenetic evolution of the Upper Jurassic limestones, currently dolomitized, that constitute the main reservoir of the Casablanca oil field. Core samples from Casablanca-1A well have been studied to determine the diagenetic products and their relation with porosity evolution, and to reconstruct the fluid flow history prior to and during oil emplacement. On the basis of petrological observations and geochemical analyses (major, minor and trace element composition and oxygen, carbon and strontium isotope composition), a major dolomitization event is recognized postdating subaerial exposure, erosion and karstification. The dolomitization event originated two replacive dolomites (RD1 and RD2) and two dolomite cements (saddle dolomite cement, SDC, and milky-white dolomite cement, MDC) which are partially cogenetic. RD1, RD2 and SDC precipitated at increasing temperatures (over 60°C and below 110°C), probably from meteoric water mixed with marine water. The last dolomite type (milky-white dolomite cement) precipitated with increasing burial conditions and by arrival of hydrothermal fluids during the Miocene. The post-dolomitization sequence comprises precipitation of calcite cement and partial calcitization of all previous dolomites. The oxygen, carbon and strontium isotope compositions suggest that this calcite cementation occurred from meteoric waters mixed with Burdigalian - Langhian marine waters trapped in the sediments and expelled by compaction in the moderate to deep burial realm. Normal faults were the conduits for upward migration of these fluids as well as for later oil expulsion from the Burdigalian - Langhian source rocks. Late corrosion associated with organic acid-enriched fluids took place prior or simultaneously to oil migration during the Pliocene, enhancing porosity and increasing reservoir quality. ; This research was supported by the Spanish Government Project CGL2010-18260 and the "Grup Consolidat de Recerca Geologia Sedimentària" 2009SGR-1451. ; Peer Reviewed