bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transport and Reaction Processes Affecting the Attenuation of Landfill Gas in Cover Soils
Authors: Molins S. , Mayer K. U. , Scheutz C. , Kjeldsen P. 
Published: February 2008

AbstractMethane and trace organic gases produced in landfill waste are partly oxidized in the top 40 cm of landfill cover soils under aerobic conditions. The balance between the oxidation of landfill gases and the ingress of atmospheric oxygen into the soil cover determines the attenuation of emissions of methane, chlorofluorocarbons, and hydrochlorofluorocarbons to the atmosphere. This study was conducted to investigate the effect of oxidation reactions on the overall gas transport regime and to evaluate the contributions of various gas transport processes on methane attenuation in landfill cover soils. For this purpose, a reactive transport model that includes advection and the Dusty Gas Model for simulation of multicomponent gas diffusion was used. The simulations are constrained by data from a series of counter‐gradient laboratory experiments. Diffusion typically accounts for over 99% of methane emission to the atmosphere. Oxygen supply into the soil column is driven exclusively by diffusion, whereas advection outward offsets part of the diffusive contribution. In the reaction zone, methane consumption reduces the pressure gradient, further decreasing the significance of advection near the top of the column. Simulations suggest that production of water or accumulation of exopolymeric substances due to microbially mediated methane oxidation can significantly reduce diffusive fluxes. Assuming a constant rate of methane production within a landfill, reduction of the diffusive transport properties, primarily due to exopolymeric substance production, may result in reduced methane attenuation due to limited O2–ingress.
Regulatory T-Cells Protect From Type 1 Diabetes After Induction by Coxsackievirus Infection in the Context of Transforming Growth Factor-β
Authors: Richer Martin J. , Straka Nadine , Fang Dianne , Shanina Iryna , Horwitz Marc S. 
Published: February 2008

OBJECTIVE—Coxsackievirus infections have long been associated with the induction of type 1 diabetes. Infection with coxsackievirus B4 (CB4) enhances type 1 diabetes onset in NOD mice by accelerating the presentation of β-cell antigen to autoreactive T-cells. It has been reported that a progressive defect in regulatory T-cell (Treg) function is, in part, responsible for type 1 diabetes onset in NOD mice. This defect may contribute to susceptibility to viral-induced type 1 diabetes. We asked whether the immune response after CB4 infection could be manipulated to reestablish peripheral tolerance while maintaining the immune response to virus.
RESEARCH DESIGN AND METHODS—NOD mice expressing transforming growth factor-β (TGF-β) specifically in the β-cells were infected with CB4, and the functional role of Tregs in disease protection was measured. Systemic treatments with TGF-β were used to assess its therapeutic potential.
RESULTS—Here, we report that Tregs induced after CB4 infection in the presence of TGF-β prevented type 1 diabetes. The capacity to directly infect pancreatic β-cells correlated with increased numbers of pancreatic Tregs, suggesting that presentation of β-cell antigen is integral to induction of diabetogenic protective Tregs. Furthermore, the presence of these viral induced Tregs correlated with protection from type 1 diabetes without altering the antiviral response. Finally, when TGF-β was administered systemically to NOD mice after infection, the incidence of type 1 diabetes was reduced, thereby signifying a potential therapeutic role for TGF-β.
CONCLUSIONS—We demonstrate manipulations of the immune response that result in Treg-mediated protection from type 1 diabetes without concomitant loss of the capacity to control viral infection.
Persistent Hyperinsulinemic Hypoglycemia and Maturity-Onset Diabetes of the Young Due to Heterozygous HNF4A Mutations
Authors: Kapoor Ritika R. , Locke Jonathan , Colclough Kevin , Wales Jerry , Conn Jennifer J. , Hattersley Andrew T. , Ellard Sian , Hussain Khalid 
Published: February 2008

OBJECTIVE—Mutations in the human HNF4A gene encoding the hepatocyte nuclear factor (HNF)-4α are known to cause maturity-onset diabetes of the young (MODY), which is characterized by autosomal-dominant inheritance and impaired glucose-stimulated insulin secretion from pancreatic β-cells. HNF-4α has a key role in regulating the multiple transcriptional factor networks in the islet. Recently, heterozygous mutations in the HNF4A gene were reported to cause transient hyperinsulinemic hypoglycemia associated with macrosomia.
RESEARCH DESIGN AND METHODS—Three infants presented with macrosomia and severe hypoglycemia with a positive family history of MODY. The hypoglycemia was confirmed to be due to hyperinsulinism, and all three patients required diazoxide therapy to maintain normoglycemia. Two of the three infants are still requiring diazoxide therapy at 8 and 18 months, whereas one of them had resolution of hyperinsulinemic hypoglycemia at 32 months of age.
RESULTS—Sequencing of the HNF4A gene identified heterozygous mutations in all three families. In family 1, a frameshift mutation L330fsdel17ins9 (c.987 1003del17ins9; p.Leu330fs) was present in the proband; a mutation affecting the conserved A nucleotide of the intron 2 branch site (c.264–21A&gt;G) was identified in the proband of family 2; and finally a nonsense mutation, Y16X (c.48C&gt;G, p.Tyr16X), was found in the proband of family 3.
CONCLUSIONS—Heterozygous HNF4A mutations can therefore cause both transient and persistent hyperinsulinemic hypoglycemia associated with macrosomia. We recommend that macrosomic infants with transient or persistent hyperinsulinemic hypoglycemia should be screened for HNF4A mutations if there is a family history of youth-onset diabetes.
On recrystallization texture formation in polycrystalline fcc alloys with low stacking fault energies
Authors: Sztwiertnia Krzysztof 
Published: February 2008

Abstract
The texture and microstructure transformations during the annealing of highly cold-rolled silver, α-brass and phosphorus copper were studied using electron microscopy and calorimetry. The results imply that recrystallization is a superposition of several local processes which proceed in two stages. In all materials analyzed, the first stage is governed by oriented nucleation, comprising the nucleation of new grains in the areas of localized strain and their further growth accompanied by the generation of recrystallization twins. The orientation distributions of nuclei and the new grains of all materials analyzed have certain features in common at the beginning of recrystallization. The second stage in phosphorus copper is governed by oriented nucleation, while in silver and in α-brass, it is dominated by oriented growth of grains, characterized by low orientation pinning.
Hardening precipitation and mechanical properties in new Mg–Mn–Y–Gd alloys
Authors: Antion Caroline , Donnadieu Patricia , Blandin Jean-Jacques , Bley Françoise , Deschamps Alexis , Tassin Catherine , Pisch Alexander 
Published: February 2008

Abstract
Precipitation microstructures and mechanical properties of two new Mg–Mn–Y–Gd alloys have been studied. Small Angle X-ray Scattering and Transmission Electron Microscopy carried out on homogeneous and aged states (200°C and 250°C) have revealed Guinier–Preston zones formed from the homogeneous state at ambient temperature and first stages of precipitation consisting in DO19 type monolayer precipitates. These ultrafine precipitates show further organisation leading to the orthorhombic β′ phase. Peak-hardness microstructure is characterised by a high density of connected β′ precipitates. Overaged samples show a high level of mechanical strength and creep resistance. The related microstructure consists of stable β′ phase precipitates forming connected strings giving rise to a local strain within the matrix. Comparison with previous studies confirms the strong relationship between rare earth elements choice, precipitation microstructure and mechanical resistance.
The surface tension and density of Ag–Bi–Sn alloys
Authors: Fima Przemysław , Kucharski Marian 
Published: February 2008

Abstract
The sessile drop method has been used to measure the density and surface tension of liquid Ag–Bi–Sn mixtures. The density of these alloys shows linear dependence on temperature for all the compositions investigated. However, the surface tension shows curvilinear dependence on temperature for all of the compositions, except for those of a low silver content. The experimental values of the surface tension of Ag–Bi–Sn alloys are compared with those computed from the model, and relatively good agreement is observed.
Study of hydrogen absorption of aluminum melt
Authors: Wu Ruizhi , Sun Baode , Shu Da , Wang Jun 
Published: February 2008

Abstract
Hydrogen absorption of aluminum melt during melt treatment is one of the important factors that affect the hydrogen content of aluminum melt. In this paper, the effects of several factors (melt temperature, atmosphere humidity, and rotary speed in the rotary impellor degassing process) on hydrogen absorption are investigated quantitatively. It is found that, the higher the melt temperature, the higher the atmospheric humidity, and the higher the rotary speed in the rotary impellor degassing process, the more serious the hydrogen absorption of melt will become.
Modelling of work-hardening behaviour for laser welded magnesium alloy
Authors: Cao X. , Jahazi M. , Al-Kazzaz H. , Medraj M. 
Published: February 2008

Abstract
To investigate the reliability of the laser welding process for the magnesium alloy ZE41A-T5, eight butt joints were welded using the same processing parameters. These joints were tensile tested in the as-welded and aged conditions and the tensile data were analyzed from work-hardening characteristics. The flow curves cannot entirely be satisfactorily described by the Kocks–Mecking model; however, the model is still applicable to the high strain zone of the flow curves where work-hardening rate decreases linearly with flow stress. The reproducibility of the initial work-hardening rate and saturation stress is statistically analyzed. The initial work-hardening rates for the base castings and welded joints vary from approximately 4000 to 7000 MPa, i. e. 1/4 to 1/3 of the base material shear modulus. The as-welded joints have slightly higher initial work-hardening rates than the base castings. Artificial aging produces lower initial work-hardening rates compared with the base material. The saturation stress ranges approximately from 260 to 320 MPa, i. e. about 2 % of the shear modulus. The saturation stress for the welded joints is lower than that for the base material. Compared with the as-weld joints, aging decreases initial work-hardening rate but slightly increases saturation stress. Both initial work-hardening rate and saturation stress become more scattered after aging.
Thermodynamic simulation of the Bayer process
Authors: Königsberger Erich 
Published: February 2008

Abstract
The Gibbs energy minimiser incorporated in the thermodynamic subroutine library ChemApp and a thermodynamically consistent, ten-component Bayer liquor model were applied to a simulation of the Bayer process employed worldwide for the refining of alumina from bauxite ores. As well as the liquor cycle from digestion, clarification, precipitation, evaporation and back to digestion (including flash cooling and heating steps), calcination to alumina in a circulating fluid bed furnace was simulated. The present study not only covers temperature and concentration ranges from boehmite digestion to gibbsite precipitation, it also permits exploration of boehmite precipitation as a potential energy saving modification of the process. Furthermore, the simulation is able to predict the accumulation and precipitation of undesirable impurities in various stages of the liquor circuit. It also identifies possible reductions in the overall energy consumption of the Bayer process.
Tribological behavior of short carbon fiber or hybrid with SiCp reinforced Al alloy composites
Authors: Tang Yiping , Huang Ziyang , Liu Yuwen , Liu Lei , Hu Wenbin 
Published: February 2008

Abstract
Aluminum alloy matrix samples reinforced with short carbon fibers or hybrid SiCp composites were prepared, and friction and wear tests were carried out on a wear test machine using a rotation ring on a stationary disk at high load. Optical microscopy, scanning electron microscopy and energy-dispersive analysis of X-rays were used to investigate the composites, worn surface, wear debris and composition changes after wear. By comparison with Al alloy, Al/SCF and Al/SCF/SiCp, the results indicate that the incorporation of SCF into Al alloys improves the wear resistance significantly, the combination of a mechanically mixed layer formed on the worn surface and hard SiCp are responsible for the good tribological properties of the hybrid Al/SCF/SiCp composites at high load. During sliding, an obvious decrease in the temperature rise with SCF addition is attributed to the good anti-friction of SCF.
Elevated temperature compressive behavior of Nb-22Ti-16Si-7Cr-3Al-3Ta-2Hf alloy with minor Ho addition
Authors: Tian Y. X. , Guo J. T. , Cheng G. M. , Sheng L. Y. , Zhou L. Z. , He L. L. , Ye H. Q. 
Published: February 2008

Abstract
The microstructure and elevated temperature compressive behavior of Nb-22Ti-16Si-7Cr-3Al-3Ta-2Hf alloys with and without 0.1 at.% Ho were investigated by using scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and compression tests. The results show that the addition of 0.1 at.% Ho to the matrix alloy significantly increases its elevated temperature strength at a higher strain rate, while the strengthening effect becomes weak at a lower strain rate. The elevated temperature compressive deformation behavior of the Ho-doped alloy can be adequately described by the power-law equation. The mechanism of Ho addition on elevated-temperature compressive behavior of the alloy is discussed in the paper.
Caulimoviridae (Plant Pararetroviruses)
Authors: Hull Roger 
Published: February 2008

Abstract
The Caulimoviridae family comprises six genera whose members replicate by reverse transcription and whose virus particles contain double‐stranded deoxyribonucleic acid (DNA); hence they are also called pararetroviruses. It is the only plant virus taxon whose members have double‐stranded DNA genomes.
Messenger
RNA
in Eukaryotes
Authors: Akusjärvi Göran , Kreivi Jan‐Peter , Petersen‐Mahrt Svend 
Published: February 2008

Abstract
Posttranscriptional regulation of gene expression represents an important level at which eukaryotes can expand the coding capacity of their genomes. The concept that one gene makes one protein does not apply to higher eukaryotes. Thus, a eukaryotic cell can use alternative ribonucleic acid (RNA) splicing, alternative polyadenylation and RNA editing to produce hundreds or even several thousands of protein isoforms from a single gene.
Hepatitis: Clinical Features and Treatment
Authors: Thomas Howard , Wright Mark 
Published: February 2008

Abstract
There are five hepatitis viruses, A–E.
Hepatitis A and E are enterically transmitted, cause an acute hepatitis, often asymptomatic, rarely fulminant and never resulting in chronic infection. The vaccine for prevention of hepatitis A infection is well established and the vaccine against hepatitis E is currently completing clinical evaluation in field trials.

Hepatitis B causes acute and chronic hepatitis, the latter resulting in cirrhosis and hepatocellular carcinoma. Infection in adult life is usually the result of sexual activity or IV drug use, results in a symptomatic self‐limiting illness and causes chronic infection in 5–10% of cases. Infection at birth or
in utero
invariably results in chronic infection. The chronic infection requires treatment with either pegylated interferon or nucleoside analogues, if there is evidence of continuing hepatitis B virus (HBV) replication (HBV DNA >10
5
genomes mL
−1
) and evidence on liver biopsy of significant liver disease.

Hepatitis D co‐infection or super‐infection is seen in some cases of HBV infection and generally results in more rapidly progressive disease.
Hepatitis C causes acute self‐limiting hepatitis in 30–40% of cases, usually after parenteral transmission as a result of inadequate sterilization of medical equipment, IV drug use or rarely after blood transfusion in countries where adequate testing of donations is not undertaken. Sexual and neonatal transmission are rare. Most cases of chronic infection develop some degree of hepatitis and fibrosis over several decades and those with cirrhosis are at risk of developing hepatocellular carcinoma. Treatment with pegylated interferon and ribavirin produces a sustained viral response with resolution of the liver disease (cure) in 50–60% of cases with 6–12 months treatment. Response rates vary from 40% in genotypes 1 and 4 to 80% in genotypes 2 and 3.
Somatic and Stem Cell Differentiationin vitro: Model Systems
Authors: Coffman Frederick D , Studzinski George P 
Published: February 2008

AbstractBecause conditions of culturein vitrocannot be identical to those in the living system, cell lines culturedin vitroare referred to as ‘model systems’. Not all cell types are capable of differentiationin vitro. Procedures for studying differentiation in model systems depend on the type of culture that can be employed. Techniques employed include liquid suspension cultures, monolayer cultures and complex culture systems involving semisolid matrices or liquid overlay methods. Recent developments include systems optimized for stem cell differentiation. Suchin vitroculture techniques have applications to the study of differentiation in basic research and clinical applications.
Posttranslational Processing: Peptide Hormones and Neuropeptide Transmitters
Authors: Varro Andrea 
Published: February 2008

Abstract
The regulatory peptides that act as hormones, paracrine messengers or neurotransmitters are generally synthesized initially as large, inactive precursors that are converted to their active forms by a variety of different posttranslational processing steps including cleavage of the peptide chain and modification to individual residues for example by sulfation, phosphorylation, glycosylation and COOH‐terminal amidation.
Tropical Forest Animal Communities
Authors: Kricher John 
Published: February 2008

Abstract
Equatorial forests are unique for their high plant and animal diversities. Diversity results from speciation and is historically related to patterns of biogeography that result in part from plate tectonics. Causal factors that generate high tropical diversity are warm and wet climate, equitable seasonality, large area, high plant productivity and complex biotic interactions leading to ecological specialization. Within the tropics, wet forests exhibit the highest animal diversity, likely due to greater plant productivity and less harsh seasonality. Some species of long‐distance migrant birds have evolved in the tropics and are integral components of tropical forests during their winter residencies. Fragmentation of forests has accelerated globally and threatens numerous animal species with potential extinction. Conservation efforts must recognize factors such as importance of large area, need for animal‐assisted pollination and seed dispersal, minimal hunting pressure and habitat connectivity.
DNA
Methylation: Evolution
Authors: Razin Aharon , Shemer Ruth 
Published: February 2008

Abstract
The understanding of how a biological feature has evolved is limited to the existing knowledge concerning this feature and the ability to interpret the available data. In an account of evolution of DNA methylation, similarities and differences in the structure of DNA methyltransferases should be considered, as well as the diversity of methylation patterns and the variety of biological processes that involve DNA methylation.
Neanderthal Mitochondrial
DNA
Authors: Goodwin William , Ovchinnikov Igor 
Published: February 2008

Abstract
Mitochondrial deoxyribonucleic acid (mtDNA) has been successfully extracted and analysed from 13 Neanderthal specimens: Feldhofer 1 and 2 from Germany; Mezmaiskaya from Russia; Vindija 75, 77 and 80 from Croatia; Engis and Scladina from Belgium, La Chapelle‐aux‐Saints and Rochers de Villeneuve from France; Monte Lessini from Italy and two specimens from El Sidrón in Spain. The Neanderthals’ mtDNA pool is distinct from modern human mtDNA and forms a separate phylogenetic clade. Using mtDNA as a molecular clock, the split between the mtDNA of modern humans and Neanderthals has been dated at around 600 000 years. The Neanderthals of 30 000–40 000 years ago display a level of sequence diversity that is very similar to modern humans.
Comparative Cytogenetics Technologies
Authors: Müller Stefan , Wienberg Johannes 
Published: February 2008

Abstract
During the last two decades, comparative cytogenetics has developed from a specialized discipline to a highly dynamic field of research. Major technological advancements have driven this development, combined with the increasing awareness that many aspects of human genome function can be better understood in an evolutionary context. Comparative chromosome and genome analysis is providing a valuable tool in various fields of basic and applied genome research, such as the identification of candidate gene loci in biomedical animal models, or for the understanding of relationships between chromosome evolution and disease. This article provides a summary of recent technical developments in the field of comparative cytogenetics and genomics, together with selected examples for their applications.
Mitochondrial Origins of Human Nuclear Genes and
DNA
Sequences
Authors: Martin William F 
Published: February 2008

Abstract
The human genome contains approximately 300 segments of mitochondrial DNA greater than 100 bp in length that were integrated during evolutionarily recent time into the nuclear chromosomes. The total number of genes encoding functional proteins in the human genome that ultimately stem from the ancestral mitochondrial genome is currently unknown, but it probably comprises a very substantial fraction of the genome.
Fibroblast Growth Factors: Evolution
Authors: Ornitz David M 
Published: February 2008

Abstract
Fibroblast growth factors (FGFs) and their receptors (FGF receptors) constitute a signalling system conserved throughout animal evolution. Most members of the FGF family signal across adjacent tissue boundaries and are essential for a variety of developmental and physiological processes. One subfamily of vertebrate FGFs, that may have originated in primitive chordates, appears to have evolved novel functions within neurons. Another subfamily of FGFs has acquired hormone‐like properties, regulating physiological processes in the adult.
Imprinting: Evolution
Authors: Spencer Hamish G 
Published: February 2008

AbstractGenomic imprinting, the differential expression of maternally and paternally derived genes, diminishes the ability to mask the deleterious effects of recessive mutations, one of the major advantages of diploidy. Nevertheless, imprinting has evolved at roughly 40 mammalian loci, and several hypotheses have been proposed to explain how the apparent disadvantage of imprinting has been overcome.
Blocks of Limited Haplotype Diversity
Authors: Morton Newton E 
Published: February 2008

Abstract
A haplotype block is a DNA sequence containing polymorphisms in strong linkage disequilibrium (LD) and with low haplotype diversity, separated from other blocks by steps of low LD with high haplotype diversity. Haplotype blocks may be as short as 2 kb or more than 150 kb, depending both on block definition and the spacing of LD cold spots, which tend to be shorter than blocks. Haplotype diversity measured by the effective number of haplotypes is said to be low if smaller than the number of polymorphisms defining the haplotype. To be useful in genetic analysis, the haplotype should be shorter than a typical block.