bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of a tropical soil and a waste from kaolin mining and their suitability as heterogeneous catalysts for Fenton and Fenton-like reactions
Authors: Pereira M. C. , Tavares C. M. , Fabris J. D. , Lago R. M. , Murad E. , Criscuolo P. S. 
Published: October 2007

AbstractAlternative Fenton and Fenton-like systems based on natural Fe oxides are described. The collected materials were modified through controlled reduction with H2 and were characterized by chemical analysis, X-ray diffraction, saturation magnetization measurements, and Mössbauer spectroscopy at 298 and 110 K. The catalytic activities of these original and modified materials were tested by studying the decomposition of H2O2 and the discolouration of methylene blue. Iron oxides present in the samples were mainly hematite and subordinate goethite which, after controlled reduction, were converted to metallic iron and magnetite. The mixture of Fe0 and magnetite in one of these materials was significantly more efficient at H2O2 decomposition and the discolouration of methylene blue than the original Fe3+ oxides. These results suggest that Fe2+ is essential to produce an active Fenton system.
Filtration and standardized properties of Jebel Om El Khecheb clay (Tunisia) and Wyoming bentonite
Authors: Laribi S. , Fleureau J.-M. , Kbir-Ariguib N. 
Published: October 2007

AbstractThe rheological and filtration properties of a Tunisian clay are presented and compared with those of Wyoming bentonite. The study was part of an evauation of Tunisian mining resources in general, and of the bentonitic deposits in particular. Qualitatively, the two clays exhibit the same rheological and filtration behaviour but quantitatively the properties of purified Wyoming bentonite are distinctly better at the same concentration. The difference can be related to the mineralogical structure and the presence of 13% illite in the Tunisian clay. Standard tests show that the rheological behaviour of the purified Tunisian clay is close to that of the raw Wyoming bentonite and conform to the American Petroluem Institute (A.P.I.) standards for medium-depth drilling formulations.
Polycation adsorption on montmorillonite: pH and T as decisive factors for the kinetics and mode of chitosan adsorption
Authors: An J.-H. , Dultz S. 
Published: October 2007

AbstractAdsorption of the polycation chitosan on montmorillonite was studied at different pH values from 4.5 to 6.5 and at temperatures of 25, 50 and 75ºC. The amount of chitosan adsorbed increased with temperature, indicating that temperature is a decisive factor. At pH 5.0 and 25ºC the amount adsorbed was 1.18 molc kg–1, whereas it was 1.5 times higher (1.79 molc kg–1) at 75ºC. The uptake of chitosan increased significantly at higher pH. This can be attributed to the decrease in the degree of protonation. Surface charge and X-ray diffraction measurements indicate that most of the chitosan is adsorbed in the interlayer, where mono- and bilayer structures are formed.The kinetics of chitosan adsorption also depend on temperature and pH. At ⩾ 50ºC, the adsorption mechanism of chitosan on montmorillonite is closest to the intraparticle diffusion model, whereas at lower temperature (25ºC) the adsorption process is closer to the pseudo-second order model. The pH of the solution affects the protonation degree of chitosan and the mode of adsorption on montmorillonite, but not the adsorption rate.For chitosan-montmorillonite prepared at pH 5.0 and 75ºC, the effective anion exchange capacity (AEC) was found to be 80% (0.36 molc kg–1) of the calculated value. The relatively large AEC and the location of most of the anion exchange sites in the interlayer make chitosan-montmorillonite an interesting prospect as an adsorbent for water-purification procedures.
Clay mineral reactions in an active geothermal area (Mt. Amiata, southern Tuscany, Italy)
Authors: Battaglia S. , Gherardi F. , Gianelli G. , Leoni L. , Origlia F. 
Published: October 2007

AbstractThis study characterizes the effects of fluid migration into a predominantly shale cover which seals the active geothermal system of Mt. Amiata (Tuscany, Italy). During Alpine orogenesis the shale unit was affected by regional metamorphism at the limit of the diagenesis-anchizone. Subsequently, the phyllosilicate clay minerals of the shales underwent significant alteration at diagenetic temperatures (175±25ºC as determined by the geochemical model) by the pervasive circulation of fluids activated by the geothermal field. The overall mineralogical assemblages indicate that the main transformations consisted mostly of destabilization of illite and formation of kaolinite together with large amounts of I-S mixed layers, with higher smectite content and decreased Reichweite I-S ordering (from R3 to R1) with respect to the original, unaltered phases. Application of computer modelling indicates that the circulation of CO2-rich geothermal fluids into the shale unit was responsible for the observed phyllosilicate clay mineral transformations.
Effect of slope aspect on transformation of clay minerals in Alpine soils
Authors: Egli M. , Mirabella A. , Sartori G. , Giaccai D. , Zanelli R. , Plötze M. 
Published: October 2007

AbstractTwo soil profile sequences on paragneiss debris in the Val di Rabbi (Northern Italy) along an altitude gradient ranging from 1200 to 2400 m a.s.l. were studied to evaluate the effect of aspect on the weathering of clay minerals. All the soils had a coarse structure, a sandy texture and a low pH. Greater weathering intensities of clay-sized phyllosilicates (greater content of smectites) were observed in soils on the north-facing slope. On the south-facing slope, smectite was found only in the surface horizon of the soil profile at the highest altitude. Hot citrate treatment of north-facing soils revealed the presence of low-charged 2:1 clay minerals, the expansion of which was hindered in the untreated state by interlayered polymers. However, the hot citrate treatment encountered some problems with the samples of the south-facing soils: as confirmed by Fourier transform infrared spectroscopy, the hot citrate treatment was unable to remove all interlayer Al polymers. The 2:1 phyllosilicates were not expanded by ethylene glycol solvation in several samples, although thermogravimetric analyses indicated the presence of clay minerals with interlayer H2O. At the same time, the collapse of clay minerals to 1.0 nm following K-saturation was evident. Theoretically, this should indicate that 2:1 phyllosilicates had no evident substitution of trioctahedral cations (Mg2+, Fe2+) by dioctahedral cations (Al3+ and Fe3+). X-ray diffraction analysis of the d060 region and determination of the layer charge of clay minerals by the long-chain (C18) alkylammonium ion, however, did not confirm this. A transformation from trioctahedral to dioctahedral species was observed and low-charge clay minerals (ξ ~0.30) were identified in the surface horizons of the south-facing sites. In the south-facing soils, the podzolization process was less pronounced because of a lower water flux through the soil and probably less complexing organic molecules that would remove the interlayer polymers. Besides the eluviation process, clay minerals underwent a process of ionic substitutions in the octahedral sheet that led to the reduction of the layer charge. This process was more obvious in the north-facing sites.
Assessment of algorithms for high throughput detection of genomic copy number variation in oligonucleotide microarray data
Authors: Baross Ágnes , Delaney Allen D , Li H Irene , Nayar Tarun , Flibotte Stephane , Qian Hong , Chan Susanna Y , Asano Jennifer , Ally Adrian , Cao Manqiu , Birch Patricia , Brown-John Mabel , Fernandes Nicole , Go Anne , Kennedy Giulia , Langlois Sylvie , Eydoux Patrice , Friedman JM , Marra Marco A 
Published: October 2007

Abstract

Background
Genomic deletions and duplications are important in the pathogenesis of diseases, such as cancer and mental retardation, and have recently been shown to occur frequently in unaffected individuals as polymorphisms. Affymetrix GeneChip whole genome sampling analysis (WGSA) combined with 100 K single nucleotide polymorphism (SNP) genotyping arrays is one of several microarray-based approaches that are now being used to detect such structural genomic changes. The popularity of this technology and its associated open source data format have resulted in the development of an increasing number of software packages for the analysis of copy number changes using these SNP arrays.

Results
We evaluated four publicly available software packages for high throughput copy number analysis using synthetic and empirical 100 K SNP array data sets, the latter obtained from 107 mental retardation (MR) patients and their unaffected parents and siblings. We evaluated the software with regards to overall suitability for high-throughput 100 K SNP array data analysis, as well as effectiveness of normalization, scaling with various reference sets and feature extraction, as well as true and false positive rates of genomic copy number variant (CNV) detection.

Conclusion
We observed considerable variation among the numbers and types of candidate CNVs detected by different analysis approaches, and found that multiple programs were needed to find all real aberrations in our test set. The frequency of false positive deletions was substantial, but could be greatly reduced by using the SNP genotype information to confirm loss of heterozygosity.
Limited genetic diversity in Salmonella enterica Serovar Enteritidis PT13
Authors: Olson Adam B , Andrysiak Ashleigh K , Tracz Dobryan M , Guard-Bouldin Jean , Demczuk Walter , Ng Lai-King , Maki Anne , Jamieson Frances , Gilmour Matthew W 
Published: October 2007

Abstract

Background

Salmonella enterica serovar Enteritidis has emerged as a significant foodborne pathogen throughout the world and is commonly characterized by phage typing. In Canada phage types (PT) 4, 8 and 13 predominate and in 2005 a large foodborne PT13 outbreak occurred in the province of Ontario. The ability to link strains during this outbreak was difficult due to the apparent clonality of PT13 isolates in Canada, as there was a single dominant pulsed-field gel electrophoresis (PFGE) profile amongst epidemiologically linked human and food isolates as well as concurrent sporadic strains. The aim of this study was to perform comparative genomic hybridization (CGH), DNA sequence-based typing (SBT) genomic analyses, plasmid analyses, and automated repetitive sequence-based PCR (rep-PCR) to identify epidemiologically significant traits capable of subtyping S. Enteritidis PT13.

Results
CGH using an oligonucleotide array based upon chromosomal coding sequences of S. enterica serovar Typhimurium strain LT2 and the Salmonella genomic island 1 successfully determined major genetic differences between S. Typhimurium and S. Enteritidis PT13, but no significant strain-to-strain differences were observed between S. Enteritidis PT13 isolates. Individual loci (safA and fliC) that were identified as potentially divergent in the CGH data set were sequenced in a panel of S. Enteritidis strains, and no differences were detected between the PT13 strains. Additional sequence-based typing was performed at the fimA, mdh, manB, cyaA, citT, caiC, dmsA, ratA and STM0660 loci. Similarly, no diversity was observed amongst PT13 strains. Variation in plasmid content between PT13 strains was observed, but macrorestriction with Bgl II did not identify further differences. Automated rep-PCR patterns were variable between serovars, but S. Enteritidis PT13 strains could not be differentiated.

Conclusion
None of the methods identified any significant variation between PT13 strains. Greater than 11,300 base pairs of sequence for each of seven S. Enteritidis PT13 strains were analyzed without detecting a single polymorphic site, although diversity between different phage types of S. Enteritidis was observed. These data suggest that Canadian S. Enteritidis PT13 strains are highly related genetically.
Abdominal obesity exhibits distinct effect on inflammatory and anti-inflammatory proteins in apparently healthy Japanese men
Authors: Nishida Makoto , Moriyama Toshiki , Sugita Yoshiro , Yamauchi-Takihara Keiko 
Published: October 2007

Abstract

Background
Since visceral fat tissue is known to release various inflammatory and anti-inflammatory cytokines, abdominal obesity may play a key role in the inflammation associated with metabolic syndrome (MetS). However, few studies have determined precise relationships of abdominal obesity with inflammatory markers in MetS. To clarify the importance of abdominal obesity in sub-clinical inflammation, we examined the changes of inflammatory markers in clustering of MetS components with or without abdominal obesity.

Methods
Subjects consisted of 326 apparently healthy Japanese men (age: 30 to 59 years) who underwent health examination in the Osaka University Health Care Center. MetS components were assessed and serum levels of high sensitive C-reactive protein (hs-CRP), interleukin (IL)-6 and adiponectin were examined in all subjects.

Results
Subjects with abdominal obesity (waist circumference ≥ 85 cm) showed higher serum hs-CRP and IL-6 levels and a lower adiponectin level than those without abdominal obesity. Serum levels of hs-CRP and IL-6 significantly increased in association with clustering of MetS components in the subjects with abdominal obesity, but not in those without abdominal obesity. On the other hand, serum adiponectin level exhibited a little change with clustering of MetS components in the subjects with abdominal obesity. Significant negative correlation between adiponectin and hs-CRP was observed in the subjects with abdominal obesity, however this correlation was not detected in obese subjects defined by body mass index ≥ 25.

Conclusion
Inflammatory status is not exaggerated by clustering of MetS components in the subjects without abdominal obesity. Abdominal obesity may exhibit distinct effect on inflammatory and anti-inflammatory proteins and modulate inflammatory network in MetS.
Human Immunodeficiency Virus Type 1 Nef protein modulates the lipid composition of virions and host cell membrane microdomains
Authors: Brügger Britta , Krautkrämer Ellen , Tibroni Nadine , Munte Claudia E , Rauch Susanne , Leibrecht Iris , Glass Bärbel , Breuer Sebastian , Geyer Matthias , Kräusslich Hans-Georg , Kalbitzer Hans Robert , Wieland Felix T , Fackler Oliver T 
Published: October 2007

Abstract

Background
The Nef protein of Human Immunodeficiency Viruses optimizes viral spread in the infected host by manipulating cellular transport and signal transduction machineries. Nef also boosts the infectivity of HIV particles by an unknown mechanism. Recent studies suggested a correlation between the association of Nef with lipid raft microdomains and its positive effects on virion infectivity. Furthermore, the lipidome analysis of HIV-1 particles revealed a marked enrichment of classical raft lipids and thus identified HIV-1 virions as an example for naturally occurring membrane microdomains. Since Nef modulates the protein composition and function of membrane microdomains we tested here if Nef also has the propensity to alter microdomain lipid composition.

Results
Quantitative mass spectrometric lipidome analysis of highly purified HIV-1 particles revealed that the presence of Nef during virus production from T lymphocytes enforced their raft character via a significant reduction of polyunsaturated phosphatidylcholine species and a specific enrichment of sphingomyelin. In contrast, Nef did not significantly affect virion levels of phosphoglycerolipids or cholesterol. The observed alterations in virion lipid composition were insufficient to mediate Nef's effect on particle infectivity and Nef augmented virion infectivity independently of whether virus entry was targeted to or excluded from membrane microdomains. However, altered lipid compositions similar to those observed in virions were also detected in detergent-resistant membrane preparations of virus producing cells.

Conclusion
Nef alters not only the proteome but also the lipid composition of host cell microdomains. This novel activity represents a previously unrecognized mechanism by which Nef could manipulate HIV-1 target cells to facilitate virus propagation in vivo.
Application of a zona pellucida binding assay (ZBA) in the domestic cat benefits from the use of in vitro matured oocytes
Authors: Hermansson Ulrika , Axnér Eva , Holst Bodil Ström 
Published: October 2007

AbstractBackgroundZona pellucida binding assays (ZBAs) have proven useful in determining the fertilising ability of spermatozoa in several species. Most ZBAs use fresh or salt-stored oocytes collected from fresh ovaries but because ovaries are not easy to obtain on a regular basis, chilled and frozen-thawed ovaries have been tested, with varying results. The present study tested the hypothesis that cat spermatozoa, either fresh or frozen-thawed, can bind to homologous zona pellucida of oocytes retrieved from frozen-thawed queen ovaries to a similar extent as they can bind to the zona pellucida of fresh,in vitromatured oocytes.MethodsOvaries were collected from queens after routine ovario-hysterectomy and either stored in NaCl at -20°C until use (treatment animals), or used fresh (controls). Cumulus-oocyte complexes (COCs) were retrieved by ovarian slicing from either source and used directly (immature oocytes from frozen-thawed ovaries; treatment animals) or afterin vitromaturation (IVM) (fresh ovaries; controls) for 24 hours in TCM 199, supplemented with 1 IU hCG/mL and 0.5 IU eCG/mL and 0.5% bovine serum albumin (BSA). The oocytes were incubated for 4 hours in 5% CO2in air at 38°C and 100% humidity in the presence of 5 × 106fresh or frozen-thawed spermatozoa/mL. Representative samples of oocytes were processed for scanning electron microscopy (SEM).ResultsBoth fresh and frozen-thawed spermatozoa bound to thein vitromatured zona pellucida but significantly fewer, or no, spermatozoa bound to frozen-thawed, immature zona pellucida (P < 0.001). Also, more fresh spermatozoa than frozen-thawed spermatozoa bound to the zona pellucida (P < 0.001). The zona pellucida surface differed in morphology (SEM), within vitromatured oocytes showing a dense surface with few fenestrations in contrast to their frozen-thawed, immature counterparts, where fenestrations were conspicuously larger.ConclusionIn conclusion, under the conditions of the present study, immature oocytes recovered from ovaries frozen immersed in NaCl at -20°C are less suitable for use in feline ZBA.
Phase II Study of Efficacy and Safety of Bevacizumab in Combination With Chemotherapy or Erlotinib Compared With Chemotherapy Alone for Treatment of Recurrent or Refractory Non–Small-Cell Lung Cancer
Authors: Herbst Roy S. , O'Neill Vincent J. , Fehrenbacher Louis , Belani Chandra P. , Bonomi Philip D. , Hart Lowell , Melnyk Ostap , Ramies David , Lin Ming , Sandler Alan 
Published: October 2007

Purpose Bevacizumab, a humanized anti–vascular endothelial growth factor monoclonal antibody, and erlotinib, a reversible, orally available epidermal growth factor receptor tyrosine kinase inhibitor, have demonstrated evidence of a survival benefit in the treatment of non–small-cell lung cancer (NSCLC). A single-arm phase I and II study of bevacizumab plus erlotinib demonstrated encouraging efficacy, with a favorable safety profile. Patients and Methods A multicenter, randomized phase II trial evaluated the safety of combining bevacizumab with either chemotherapy (docetaxel or pemetrexed) or erlotinib and preliminarily assessed these combinations versus chemotherapy alone, as measured by progression-free survival (PFS). All patients had histologically confirmed nonsquamous NSCLC that had progressed during or after one platinum-based regimen. Results One hundred twenty patients were randomly assigned and treated. No unexpected adverse events were noted. Fewer patients (13%) in the bevacizumab-erlotinib arm discontinued treatment as a result of adverse events than in the chemotherapy alone (24%) or bevacizumab-chemotherapy (28%) arms. The incidence of grade 5 hemorrhage in patients receiving bevacizumab was 5.1%. Although not statistically significant, relative to chemotherapy alone, the risk of disease progression or death was 0.66 (95% CI, 0.38 to 1.16) among patients treated with bevacizumab-chemotherapy and 0.72 (95% CI, 0.42 to 1.23) among patients treated with bevacizumab-erlotinib. One-year survival rate was 57.4% for bevacizumab-erlotinib and 53.8% for bevacizumab-chemotherapy compared with 33.1% for chemotherapy alone. Conclusion Results for PFS and overall survival favor combination of bevacizumab with either chemotherapy or erlotinib over chemotherapy alone in the second-line setting. No unexpected safety signals were noted. The rate of fatal pulmonary hemorrhage was consistent with previous bevacizumab trials. The toxicity profile of the bevacizumab-erlotinib combination is favorable compared with either chemotherapy-containing group.
A Seven‐Step Instructional Plan for Teaching English‐Language Learners to Comprehend and Use Homonyms, Homophones, and Homographs
Authors: Jacobson Julie , Lapp Diane , Flood James 
Published: October 2007

For English‐language learners, comprehension can be hindered by a lack of understanding of homonyms, homophones, and homographs, but the right instructional strategies can alleviate this problem. Following a discussion of issues such as the importance of being aware of a student's literacy skills in his or her home language and the need to preteach key vocabulary words, the authors provide examples of a structured approach to teaching homonyms, homophones, and homographs.This seven‐step instructional process, which incorporates reading, illustrating, comparing and contrasting words, and categorizing vocabulary by using symbols to represent grammatical structures, can be used to teach all students, but it accommodates particularly the challenges encountered by English‐language learners. The seven steps areReading and/or listening to a storyDefining and visualizing wordsIdentifying parts of speechCategorizing wordsCompleting cloze activitiesProducing a skit or creating a visualPlaying a word game with new wordsThe authors offer explicit examples of instruction at each step and conclude with a discussion of how to assess students' proficiencies as they discern word meanings and begin to use words efficiently.