bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantification of hematite from the visible diffuse reflectance spectrum: effects of aluminium substitution and grain morphology
Authors: Liu Q. S. , Torrent J. , Barrón V. , Duan Z. Q. , Bloemendal J. 
Published: March 2011

AbstractHematite exists ubiquitously in soils and sediments, and is commonly aluminium (Al)-substituted. This study investigated systematically the effects of Al substitution on the visible diffuse reflectance spectrum (DRS) of hematite by using several sets of synthetic samples. We found that the position and amplitude of the characteristic absorption band of hematite (estimated from the first- and second-order derivative curves of the Kubelka-Munk remission function spectrum derived from the DRS) was significantly affected by the degree of Al substitution as well as by sample grain morphology. Therefore, there are ambiguities in quantifying the degree of Al substitution and the mass concentration of hematite using DRS. Nevertheless, if hematite forms under similar environmental conditions, it is possible to establish a transfer function between the DRS parameters and hematite concentration as discussed here for a Chinese loess-palaeosol sequence.
Identification and use of white clayey deposits from the area of Tamra (northern Tunisia) as ceramic raw materials
Authors: Moussi B. , Medhioub M. , Hatira N. , Yans J. , Hajjaji W. , Rocha F. , Labrincha J. A. , Jamoussi F. 
Published: March 2011

AbstractWhite clayey geomaterials were collected from northeast of the Nefza region (northern Tunisia). These deposits belong to the Mio-Pliocene molassic basins (basin of Tamra-Sidi Dris, Boukhchiba) and Oligocene Numidien in the area of El Aouinet. Analysis by X-ray diffraction showed associations of halloysite and kaolinite (Tamra), kaolinite and illite (Aouinet zone) and mixed layers, kaolinite and feldspars (Boukhchiba zone). Semi-industrial processed bricks showed promising characteristics and were visibly free of defects. Ceramic tiles had a bending strength that met the required standards but water absorption was somewhat high. So, to achieve higher quality, optimisation needs to be carried out in the formulation of batches or in the processing conditions. Finally, the incorporation in whitish sanitary-ware glaze formulations generated smooth coating layers that showed the required strong brightness and were free of defects.
Evaluation of mineral composition and petrophysical parameters by the integration of core analysis data and wireline well log data: the Carpathian Foredeep case study
Authors: Zorski T. , Ossowski A. , Środoń J. , Kawiak T. 
Published: March 2011

AbstractKnowledge of mineral composition is helpful in the interpretation of well-logging data, where the hydrocarbon saturation is expected as the final result.It is calculated from the electric resistivity, cation exchange capacity (CEC) and porosity.Porosity is calculated from the bulk density, which is measured directly in the well, and the matrix (mineralogical, grain) density, which can be calculated precisely only when the mineral composition is known.In the shale-sand formations, which are the subject of this study, the rock matrix can conduct electric current.The Waxman–Smits formula is applied to calculate the water saturation of such rocks.This formula combines rock porosity, water saturation, water resistivity and the CEC with the total rock resistivity measured in the well.CEC is introduced to this formula as the parameter determining the shale ability to conduct electricity.Typically, CEC is controlled by the smectite content of the rock.In order to evaluate the input data needed in the log interpretation the extended mineralogical (quantitative mineral composition, CEC) and chemical (major, trace and REE) analyses were made for over 200 core samples obtained from four gas fields in the Miocene formation of the Carpathian Foredeep.The most important clay component: the sum of mixed-layer illite-smectite and discrete illite has been quantified.The detailed recognition of clay minerals allowed for constraining the density-neutron cross-plot, which is a well log data interpretation technique for the determination of both porosity and shale content in shale-sand formations.The statistical multivariate analysis of all data helped to set up a comprehensive petrophysical model.A reliable correlation (r2 = 0.96) of the thermal neutron absorption cross-section (Σama) and the total natural radioactivity (GR) with CEC was established.Such good correlation allows for a continuous on-line CEC determination and therefore a reliable application of the Waxman-Smits water saturation model.Experimental equations with similar level of correlation were established for quartz, clay and carbonate contents, allowing the calculation of matrix density, required in the porosity calculation.The high correlation of Σama with CEC reflects the presence of boron in the illite-smectite clays.
Influence of hydrocarbon contamination on clay soil microstructure
Authors: Izdebska-Mucha D. , TrzcińSk J. , Żbik M. S. , Frost R. L. 
Published: March 2011

AbstractMicrostructural (fabric, forces and composition) changes due to hydrocarbon contamination in a clayey soil (glacial till) were studied using scanning electron microscopy (microfabric analysis), atomic force microscopy (force measurement) and a sedimentation bench test (particle size measurements). Non-polluted and polluted glacial till from NE Poland (in the area of a fuel terminal) were used for the study. Electrostatic repulsive forces in the polluted samples were much lower than in non-polluted samples. In comparison with non-polluted samples, the polluted samples exhibited lower electric charge, attractive forces on approach and strong adhesion on withdrawal. The results of the sedimentation tests indicate that clay particles form larger aggregates and settle out of the suspension rapidly in diesel oil. In non-polluted soil, the fabric is strongly aggregated – dense packing, dominating face-to-face and edge-to-edge types of contacts, clay film tightly adhering to the surface of larger grains and interparticle pores are more common. In polluted soil the clay matrix is less aggregated – loose packing, dominating edge-to-face types of contacts and inter-micro-aggregate pores are more frequent. Substantial differences were observed in the morphometric and geometrical parameters of the pore space. The polluted soil micro-fabric proved to be more isotropic and less oriented than in non-polluted soil. The polluted soil, in which electrostatic forces were suppressed by hydrocarbon interaction, displays more open porosity and larger voids than non-polluted soil, which is characterized by the occurrence of strong electrostatic interaction between the clay particles.
Diagenesis of Miocene pelitic sedimentary rocks in the Sava Depression (Croatia)
Authors: Grizelj A. , Tibljaš D. , Kovačić M. , Španić D. 
Published: March 2011

AbstractMiocene pelitic sedimentary rocks from six wells in the Sava Depression (sub-basin in the south-western part of the Pannonian Basin System) were investigated in order to determine the degrees of diagenetic alteration.Qualitative and semiquantitative mineral compositions of samples and the content of smectite in illite-smectite (I-S) were determined by X-ray powder diffraction (XRD).Vitrinite reflectance and thermal alteration index (TAI) were measured in order to estimate the palaeotemperatures.Carbonate minerals, clay minerals and quartz are the main constituents of the pelitic sediments.Feldspars (albite), pyrite, opal-CT and hematite are present as minor constituents in some rocks. The mineral composition of the rocks, apart from previously known differences caused by various depositional environments and clastic material provenance, is dependent on the degree of diagenetic processes. At elevated temperatures and large burial depths the minerals formed by alteration processes or precipitated at the surface; smectite, kaolinite and calcite were gradually replaced by minerals formed by diagenetic processes, i.e. by illite-smectite, illite, chlorite, Ca-excess dolomite/ankerite and albite. Based on XRD data for smectite, I-S and illite, three stages of diagenetic development have been established. The early stage was characteristic of samples at depths <1.8 km containing smectite, I-S of the random R0 type and detrital illite.The middle stage begins with the appearance of the orderedR1 type of I-S at the depths >1.8 km and temperature above 80°C. At depths >4.6 km with corresponding temperatures >190ºC, the late stage began, characterized by the presence ofR>1 I-S with <10% smectite.
SO2adsorption on acid-treated bentonites from Turkey
Authors: Sakizci M. , Erdoğan Alver B. , Yörükoğullari E. 
Published: March 2011

AbstractThe adsorption of sulphur dioxide (SO2) on two bentonites from Unye, Turkey (Kavaktepe and Yemişlitepe deposits – denoted below as BK and BY) and on forms treated with 1 and 2MHCl solutions was investigated. The bentonite samples were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), thermogravimetry (TG-DTG), differential thermal analysis (DTA) and nitrogen adsorption methods. Adsorption capacities of SO2were obtained using a standard volumetric apparatus at 293 K and 106 kPa. The SO2adsorption capacity of the BY-2 (1.263 mmol g–1) sample was much greater than the BK-2 (1.126 mmol g–1) sample. As the concentration of acid increased, the specific surface areas and the uptakes of SO2gas increased.
Building Knowledge from Failure Analysis of Plastic Pipe and Other Hydraulic Structures
Authors: Sharff Phillip A. , Bellemare Simon C. , Witmer Lisa M. 
Published: March 2011

Abstract
Structural plastics have long shown exceptional performance in products used for fluid transport and containment, such as pipes, tanks, and drainage structures. The development and use of plastics enhances the versatility and durability of these important infrastructure components, as well as their economy. However, like all materials, plastics have performance limitations, and serious failures can occur as the result of improper design, fabrication, or installation. Understanding failure mechanisms of plastics can provide valuable insight into those limitations and aid the designer, manufacturer, and installer in optimizing structural and functional performance. We review forensic techniques, including field investigation, material and mechanical laboratory tests, optical and scanning electron microscopy, and stress analysis. The example cases highlight mechanical, environmental and installation issues. These include failure to account for material creep and fatigue, defects in fusion bonding, incompatibility of solvent cement, strength limitation of joint elements, and improper installation techniques. The case studies suggest ways to avoid similar mistakes in the future.
Arabic Children's Literature Today: Determining Factors and Tendencies
Authors: Dünges Petra 
Published: March 2011

Dedicated to the memory of Muḥiyy al-Dīn al-Labbād (1940–2010)In spite of great obstacles, modern arabic children's literature has seen remarkable developments lately, both in quality of text and illustrations and in breadth of subject matter. Moreover, the intricate question of which variety of Arabic to use in writing for children can now be answered in different ways, closely linked to different conceptions of Arab culture.
Azithromycin May Inhibit Interleukin‐8 Through Suppression of Rac1 and a Nuclear Factor‐Kappa B Pathway in KB Cells Stimulated With Lipopolysaccharide
Authors: Matsumura Yusuke , Mitani Akio , Suga Takayuki , Kamiya Yosuke , Kikuchi Takeshi , Tanaka Shigehisa , Aino Makoto , Noguchi Toshihide 
Published: March 2011

Background: Recent studies have shown that the 15‐member macrolide antibiotic azithromycin (AZM) not only has antibacterial activity, but also results in the role of immunomodulator. Interleukin (IL)‐8 is an important inflammatory mediator in periodontal disease. However, there have been no reports on the effects of AZM on IL‐8 production from human oral epithelium. Therefore, we investigated the effects of AZM on IL‐8 production in an oral epithelial cell line.Methods: KB cells were stimulated by Escherichia coli or Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) lipopolysaccharide (LPS) with or without AZM. IL‐8 mRNA and protein expression and production in response to LPS were analyzed by quantitative polymerase chain reaction, flow cytometry, and enzyme‐linked immunosorbent assay. The activation of nuclear factor‐kappa B (NF‐κB) and Rac1, which is important for IL‐8 expression, was analyzed by enzyme‐linked immunosorbent assay and Western blotting, respectively.Results: IL‐8 mRNA expression, IL‐8 production, and NF‐κB activation in LPS‐stimulated KB cells were inhibited by the addition of AZM. LPS‐induced Rac1 activation was also suppressed by AZM.Conclusions: This study suggests that AZM inhibits LPS‐induced IL‐8 production in an oral epithelial cell line, in part caused by the suppression of Rac1 and NF‐κB activation. The use of AZM might provide possible benefits in periodontal therapy, with respect to both its antibacterial action and apparent anti‐inflammatory effect.
Orofacial Myiasis of the Gingiva and Nasal Cavity: A Report of Two Cases and General Review
Authors: Avula Jaya Kumar , Avula Haritha , Arora Nupur , Manchukonda Udaya Kumar , VivekaVardhan Reddy Nalla 
Published: March 2011

Background:Infestation of the orofacial region with live maggots is a distressing condition and many clinicians are not aware of the existence of such an entity. Usually the condition affects individuals who are debilitated, mentally challenged, and physically not able to attend to their personal needs because of lack of psychomotor coordination.Methods:This article describes two cases of orofacial myiasis reported at a rural dental school in India. Removal of the live maggots, supportive treatment, management of the cases, and morphologic features of maggots are described.Results:Both the patients belonged to a low socioeconomic group and were physically and mentally challenged. Maggot removal improved the patients’ pain and distress, and entomologic study identified the maggots as belonging toChrysomya bezziana.Conclusions:Oral myiasis is more prevalent than commonly believed to be and an astute practitioner should be aware of such maggots in the mouth, in cases of oral and maxillofacial trauma and in vulnerable categories of patients. These patients are not physically or mentally endowed to ward off flies or complain about worms burrowing their way into oral wounds. Occurrences of such cases are rare in developed countries and reflect the lack of special care for the vulnerable group of patients belonging to certain geographic areas.
Periodontal Status of Patients With Hypophosphatemic Rickets: A Case Series
Authors: Ye Ling , Liu Ruohong , White Nicholas , Alon Uri S. , Cobb Charles M. 
Published: March 2011

Background: It was previously reported that dentin matrix protein 1–null mice, which are the hypophosphatemic rickets animal model, postnatally developed severe periodontal defects. However, to the best of our knowledge, it was not documented whether similar periodontal defects were present in human patients with hypophosphatemic rickets. The aim of this study is to evaluate the periodontal status of adult patients with hypophosphatemic rickets.Methods: This case‐series study evaluates the periodontal condition of adults with genetic hypophosphatemic rickets and compared their periodontal status with similar data from several cycles of the National Health and Nutrition Examination Survey (NHANES). Information regarding medical histories, dental histories, intraoral photos, probing depths (PD), calculated clinical attachment loss (AL), the presence of gingival recession, bleeding on probing, and full‐mouth radiographic surveys were acquired. Descriptive statistics were used for comparison to NHANES data.Results: A total of 10 adult patients with hypophosphatemic rickets (two males and eight females) were evaluated. The definition of periodontitis used in this study is as follows: “A periodontitis case was defined as a person who had ≥ 3 sites with clinical AL ≥ 4 mm and ≥ 2 sites with PD ≥ 3 mm.” According to this definition, the patients exhibited periodontal bone loss at a much higher prevalence (60%) compared to the reported national periodontitis prevalence (3.6% to 7.3%).Conclusion: The preliminary data from our study suggests that patients with hypophosphatemic rickets are more prone to periodontal bone loss than the general population and may require a more careful examination by dental care providers.
Proliferation of Smooth Muscle Cells Stimulated by Porphyromonas Gingivalis is Inhibited by Apple Polyphenol
Authors: Inaba Hiroaki , Tagashira Motoyuki , Kanda Tomomasa , Amano Atsuo 
Published: March 2011

Background: Porphyromonas gingivalis (Pg) is thought to be involved in the progression of occlusive arterial lesions, whereas vascular smooth muscle cell (SMC) proliferation is considered to be involved in occlusive arterial disease. We previously showed that bacteremia caused by Pg infection induced proliferation of mouse aortic SMCs. Furthermore, human SMCs stimulated with human plasma incubated with Pg showed a marked transformation from the contractile to proliferative phenotype. In the present study, we examine the involvement of Pg gingipains and fimbriae in induction of the SMC transformation and proliferation, and effective inhibitors.Methods: Pg strains including gingipain‐ and fimbria‐null mutants were incubated in human plasma, after which the bacteria were removed and the supernatants were added to cultured SMCs. To evaluate the effects of inhibitors, Pg organisms were incubated in plasma in the presence of apple polyphenol (AP), epigallocatechin gallate, KYT‐1 (Arg‐gingipain inhibitor), and KYT‐36 (Lys‐gingipain inhibitor).Results: Plasma supernatants from wild‐type and fimbria‐mutant cultures markedly stimulated cellular proliferation, whereas those containing gingipain‐null mutants showed negligible effects. SMC proliferation was also induced by plasma treated with trypsin. Furthermore, plasma supernatants cultured in the presence of KYT‐1/KYT‐36 and AP showed significant inhibitory effects on SMC proliferation, whereas cultures with epigallocatechin gallate did not.Conclusion: Our results suggest that Pg gingipains are involved in the induction of SMC transformation and proliferation, whereas this was inhibited by AP.
Azithromycin Concentrations in Blood and Gingival Crevicular Fluid After Systemic Administration
Authors: Lai Pin‐Chuang , Ho Weiting , Jain Nidhi , Walters John D. 
Published: March 2011

Background: Azithromycin is a macrolide antibiotic that is active against several periodontal pathogens. Macrolides are taken up and concentrated inside gingival fibroblasts, which could influence their pharmacokinetics. This study tests the hypothesis that steady‐state levels of azithromycin are higher and more sustained in gingival crevicular fluid (GCF) than in serum.Methods: Four healthy patients received an initial dose of 500‐mg azithromycin followed by 250‐mg doses on each of the next 2 days. Serum and GCF samples were obtained 2 hours after the last dose on day 2, and on days 4 and 7. GCF samples were collected from maxillary posterior sites with paper strips. The strips were pooled and eluted with high‐purity water. After extraction, the azithromycin content of the serum samples and GCF eluates was determined with an agar diffusion bioassay.Results: On days 2, 4, and 7, the concentrations of azithromycin in blood serum were 0.22 ± 0.02, 0.08 ± 0.02, and 0.04 ± 0.01 μg/mL, respectively. The concentrations in GCF were 8.82 ± 1.25, 7.90 ± 1.72, and 7.38 ± 1.15 μg/mL, respectively. Mean GCF levels were significantly higher than mean serum levels (P ≤0.02; paired t test).Conclusions: The findings demonstrate that the pharmacokinetic profiles of azithromycin are different in GCF and serum. At steady state, azithromycin concentrations in GCF were higher and more sustained than those in serum. Based on previous studies, the levels observed in GCF were above the minimal inhibitory concentration for Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, and Prevotella intermedia.
Long‐Term Efficacy of Subantimicrobial‐Dose Doxycycline as an Adjunctive Treatment to Scaling and Root Planing: A Systematic Review and Meta‐Analysis
Authors: Sgolastra Fabrizio , Petrucci Ambra , Gatto Roberto , Giannoni Mario , Monaco Annalisa 
Published: March 2011

Background: Subantimicrobial‐dose doxycycline (SDD) is widely used as an adjunctive treatment to scaling and root planing (SRP), but its long‐term effectiveness remains controversial. The purpose of this systematic review was to assess the actual evidence of the effectiveness of SRP + SDD compared to SRP + placebo in the treatment of chronic periodontitis.Methods: A literature search of electronic databases was performed for articles published through November 1, 2010. Several dental journals were screened during the manual search, and authors were contacted for missing information. The systematic review and meta‐analysis were conducted according to the Quality of Reporting of Meta‐Analyses statement and recommendations of the Cochrane Collaboration. The methodologic quality of the studies was determined via a Consolidated Standards of Reporting Trials–based assessment. Clinical attachment levels, probing depths, plaque and gingival indices, and gingival crevicular fluid levels were compared between baseline and the end of follow‐up. Data were extracted and pooled using a random‐effect model. The weighted mean difference was reported with the 95% confidence interval. Heterogeneity was assessed using the χ2‐based Q‐statistic method and I2 measurement. P <0.05 was considered statistically significant.Results: After applying inclusion and exclusion criteria, three randomized placebo‐controlled clinical trials were entered into the meta‐analysis. These studies had similar treatment designs, SDD dosage regimens (20 mg twice daily for 3 months), and post‐treatment follow‐up lengths (9 months). Significant differences were observed for all investigated clinical parameters in favor of the SRP + SDD group.Conclusion: The meta‐analysis results seemed to support the long‐term effectiveness of adjunctive SDD therapy; however, future studies are needed to confirm these findings.