bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perovskite-type hydrides – synthesis, structures and properties
Authors: Ikeda Kazutaka , Sato Toyoto , Orimo Shin-ichi 
Published: May 2008

Abstract
The present study gives an overview of the fundamental material properties of perovskite-type hydrides. Formation ability of the perovskite-type hydrides has been reasonably explained on the basis of the geometric restrictions on the composed ions using the Goldschmidt tolerance factor. Characteristic crystal structures and charge density maps of the perovskite-type hydrides without/with transition metals, such as NaMgH3/CaNiH3, were also examined in detail to clarify the relationship between the structures (atomic and electronic) and the hydriding properties.
On the small scale character of the stress and hydrogen concentration fields at the tip of an axial crack in steel pipeline: effect of hydrogen-induced softening on void growth
Authors: Dadfarnia Mohsen , Sofronis Petros , Somerday Brian P. , Robertson Ian M. 
Published: May 2008

Abstract
Gaseous hydrogen transport at pressures of 15 MPa is envisaged as a means of hydrogen delivery from central production facilities to refueling stations for the planned hydrogen economy. The study of the hydrogen embrittlement of medium or mild strength steels, which are under consideration for pipeline materials, has not as of yet led to methods to design safe and reliable pipelines. The most important failure modes in hydrogen containment components are due to subcritical cracking. However, current design guidelines for pipelines only tacitly address subcritical cracking by applying arbitrary, conservative safety factors on the applied stress. In the present work, we investigate the interaction of hydrogen transport with material elastoplasticity in the neighborhood of an axial crack in a steel pipeline. For all practical purposes, we find that the stress, deformation, and hydrogen fields exhibit a small scale character which allows for the use of the standard modified boundary layer approach to the study of the fracture behavior of steel pipelines. The approach is based on constraint fracture mechanics methodology whereby a two-parameter characterization – the stress intensity factor and the T-stress – is used to describe the interaction of the stress and deformation fields with the diffusing hydrogen under conditions of hydrogen uptake from the crack faces and outgassing through the outer boundaries, as in the pipeline. Employing the Rice and Tracey model of void growth, we find that hydrogen-induced softening can accelerate void growth in a small region confined at the crack tip by as much as 70 % relative to the case of a hydrogen-free material. We close by suggesting that one can ascertain the hydrogen effects on fracture at an axial pipeline crack with the use of a laboratory fracture mechanics specimen tested in hydrogen gas and subjected to the same intensity factor, and hydrostatic constraint, T-stress, as the real-life pipeline.
The need of data harmonization to derive robust empirical relationships between soil conditions and vegetation
Authors: Bartholomeus Ruud P. , Witte Jan‐Philip M. , van Bodegom Peter M. , Aerts Rien 
Published: May 2008

AbstractQuestion:Is it possible to improve the general applicability and significance of empirical relationships between abiotic conditions and vegetation by harmonization of temporal data?Location:The Netherlands.Methods:Three datasets of vegetation, recorded after periods with different meteorological conditions, were used to analyze relationships between soil moisture regime (expressed by the mean spring groundwater level –MSLt calculated for different periods) and vegetation (expressed by the mean indicator value for moisture regime Fm). For each relevé, measured groundwater levels were interpolated and extrapolated to daily values for the period 1970–2000 by means of an impulse‐response model. Sigmoid regression lines between MSLt and Fm were determined for each of the three datasets and for the combined dataset.Results:A measurement period of three years resulted in significantly different relationships between Fm and MSLt for the three datasets (F‐test, p < 0.05). The three regression lines only coincided for the mean spring groundwater level computed over the period 1970–2000 (MSLclimate) and thus provided a general applicable relationship. Precipitation surplus prior to vegetation recordings strongly affected the relationships.Conclusions:Harmonization of time series data (1) eliminates biased measurements, (2) results in generally applicable relationships between abiotic and vegetation characteristics and (3) increases the goodness of fit of these relationships. The presented harmonization procedure can be used to optimize many relationships between soil and vegetation characteristics.
A laboratory study of particle ploughing and pore-pressure feedback: a velocity-weakening mechanism for soft glacier beds
Authors: Thomason Jason F. , Iverson Neal R. 
Published: May 2008

AbstractIf basal-water discharge and pressure are sufficiently high, a soft-bedded glacier will slip over its bed by ploughing, the process in which particles that span the ice–bed interface are dragged across the bed surface. Results of laboratory experiments indicate that resistance to ploughing can decrease with increasing ploughing velocity (velocity weakening). During ploughing at various velocities (15–400 m a−1), till was compacted in front of idealized particles, causing pore pressures there that were orders of magnitude higher than the ambient value. This excess pore pressure locally weakened the till in shear, thereby decreasing ploughing resistance by a factor of 3.0–6.6 with a six-fold increase in ploughing velocity. Characteristic timescales of pore-pressure diffusion and compaction down-glacier from ploughing particles depend on till diffusivity, ploughing velocity and sizes of ploughing particles. These timescales accurately predict the ranges of these variables over which excess pore pressure and velocity weakening occurred. Existing ploughing models do not account for velocity weakening. A new ploughing model with no adjustable parameters predicts ploughing resistance to no worse than 38% but requires that excess pore pressures be measured. Velocity weakening by this mechanism may affect fast glacier flow, sediment transport by bed deformation and basal seismicity.
Temporal and spatial variability of surface mass balance at Dome Fuji, East Antarctica, by the stake method from 1995 to 2006
Authors: Kameda Takao , Motoyama Hideaki , Fujita Shuji , Takahashi Shuhei 
Published: May 2008

AbstractThe surface mass balance (SMB) at Dome Fuji, East Antarctica, was estimated using 36 bamboo stakes (grid of 6 × 6, placed at 20 m intervals) from 1995 to 2006. The heights of the stake tops from the snow surface were measured at 0.5 cm resolution twice monthly in 1995, 1996, 1997 and 2003, and once a year for the rest of the study period. To account for snow settling, the average snow density at the stake base during the measurements was used for converting the stake-height data to SMB. The annual SMB from 1995 to 2006 at Dome Fuji was 27.3 ± 1.5 kg m−2 a−1. This result agrees well with the annual SMB from AD 1260 to 1993 (26.4 kg m−2 a−1) estimated from volcanic signals in the Dome Fuji ice core. Over the period 1995–2006, there were 37 (8.6% of the measurements) negative or zero annual SMB results. Variation in the multi-year averages of annual SMB decreased with the square root of the number of observation years, and 10 years of observations of a single stake allowed the estimation of annual SMB at ±10% accuracy. The frequency distributions of annual and monthly SMB were examined. The findings clarify the complex behavior of the annual and monthly SMB at Dome Fuji, which will be common phenomena in areas of low snow accumulation of the interior of the Antarctic ice sheet.
Spatial mapping of multi-year superimposed ice on the glacier Kongsvegen, Svalbard
Authors: Brandt Ola , Kohler Jack , Lüthje Mikael 
Published: May 2008

AbstractGround-penetrating radar (GPR) and satellite ERS-2 synthetic aperture radar (SAR) are used to map the thickness and extent of the superimposed ice (SI) zone on the surge-type glacier Kongsvegen, Svalbard. GPR imagery shows sub-horizontal SI layers lying unconformably above a discrete boundary. Below this boundary, the ice has a GPR signature similar to that of ice further down-glacier in the ablation zone. This boundary is posited to represent the closing of crevasses that were created during the last surge of Kongsvegen in ∼1948. Open crevasses would have interrupted the formation of sheet layers of SI due to efficient vertical drainage of the snowpack. Aerial photographs suggest that the crevasses closed sometime in the period 1956–66. A classified SAR image from 2003 is used to delineate the extent of the SI zone. The SI extent in the SAR image agrees well with the SI zone mapped by GPR. Using the SI spatial depth distribution, we estimate the mean annual accumulation of superimposed ice to be 0.16 ± 0.06 m w.e. a−1 (locally up to 0.43 m a−1 w.e.). This corresponds to ∼15–33% of the local winter balance and ∼5–10% of the total winter balance measured since 1987.
Flow-switching and water piracy between Rutford Ice Stream and Carlson Inlet, West Antarctica
Authors: Vaughan David G. , Corr Hugh F.J. , Smith Andy M. , Pritchard Hamish D. , Shepherd Andrew 
Published: May 2008

AbstractRutford Ice Stream and Carlson Inlet are neighbouring glaciers in West Antarctica. Rutford Ice Stream flows at speeds greater than 350 m a−1, whereas Carlson Inlet, which has some similar dimensions and supports a similar driving stress, flows 10–50 times slower. We discuss a range of observations concerning Carlson Inlet, and conclude that there is good indirect evidence that it is a relict ice stream, which ceased streaming more than 240 years BP, but sufficiently recently that its surface morphology, basal water content and basal morphology still retain characteristics produced by streaming. An analysis of expected subglacial drainage pathways indicates that Carlson Inlet is not streaming because it is currently starved of subglacial water, which is currently directed beneath Rutford Ice Stream. This current state of water piracy by Rutford Ice Stream is, however, sensitive to minor thickness changes on the ice streams; a ∼120 m (<4%) thickening of Rutford Ice Stream would divert almost all the subglacial water in the system towards Carlson Inlet and could reactivate its flow. The result highlights the importance of subglacial drainage in controlling ice-stream evolution and the requirement for ice-sheet models to couple ice flow with subglacial drainage.
Secular changes in stature and body mass index for Chinese youth in sixteen major cities, 1950s–2005
Authors: Ji Cheng‐Ye , Chen Tian‐Jiao 
Published: May 2008

AbstractEvidence shows a secular trend in physical growth in China in recent years. We analyze the secular trend of stature and body mass index (BMI) for the period 1950s–2005 to provide biological evidence for policy‐makers to identify measures for improving Chinese children's health. Data come from the historical records in 1950s and the successive cycles of the Chinese National Survey on Student's Constitution and Health. Subjects were 7‐ to 18‐year‐old youth from 16 cities. Sex–age differences in mean stature and BMI values between the surveys were analyzed, and the increments per decade were compared. An overall positive secular trend was found in 1950s–2005. Mean stature of the 18‐year olds increased from 166.6 to 173.4 cm for males and from 155.8 to 161.2 cm for females, yielding rates of 1.3 and 1.1 cm/decade; the overall increments of BMI values were 2.6 for males and 1.8 for females, yielding rates of 0.8 and 0.6/decade, respectively. The most significant changes occurred during puberty. The overall positive secular trend is closely associated with the socioeconomic progress and the improvement of livelihood. Strong evidence suggests that in China this trend will be continued for many years. Further studies are needed to explore how to ensure healthy changes for poorer rural youth. Effective preventive strategies and measures should be taken to prevent the progressive increase in the prevalence of childhood obesity accompanying this trend. Am. J. Hum. Biol., 2008. © 2008 Wiley‐Liss, Inc.
Interstitial deletion of 1p22.2p31.1 and medium‐chain acyl‐CoA dehydrogenase deficiency in a patient with global developmental delay
Authors: Maegawa Gustavo H.B. , Poplawski Nicola K. , Andresen Brage Storstein , Olpin Simon E. , Nie Gloria , Clarke Joe T.R. , Teshima Ikuko 
Published: May 2008

AbstractWe report on a 6‐year‐old girl who presented at 6 months of age with seizures, delayed psychomotor development and mild facial dysmorphism. A small muscular ventricular septal defect was documented on echocardiogram and brain MRI showed a frontal brain anomaly. Urine organic acid analysis revealed dicarboxylic aciduria, and plasma acylcarnitine analysis showed marked elevation of octanoyl (C8) and decanoyl (C10) carnitines with C8:C10 ratio of 9:1. These results were indicative of medium chain acyl‐CoA dehydrogenase deficiency. ACADM gene sequencing showed an apparent homozygous c.166G > C (Ala31Pro) missense mutation in exon 3; however, only the mother was found to be a carrier of this novel missense mutation. This finding along with non‐regressive developmental delay prompted further karyotype and genomic investigations. An interstitial deletion of chromosome 1 was detected by repeat G‐banding: 46,XX,del(1)(p22.2p31.1). Parental karyotypes were normal. The deletion was characterized by array CGH analysis using a 1 Mb BAC/PAC array platform. Clones deleted extended from RP11‐88B10 (1p31.1) to RP5‐1007M22 (1p22.2), a 15.5 Mb deletion which includes the ACADM locus. Clinical review of 6/7 cases of interstitial deletions with breakpoints of 1p22 and 1p31/32, including the patient in this report, indicate a variable phenotype. Thus, although G‐band breakpoints are similar, common breakpoints for these alterations are unlikely. This is the first report of a patient with fatty acid oxidation defect caused by a mutation in combination with an interstitial chromosomal deletion. © 2008 Wiley‐Liss, Inc.
A novel mutation in IRF6 resulting in VWS–PPS spectrum disorder with renal aplasia
Authors: de Medeiros Filipe , Hansen Lars , Mawlad Evete , Eiberg Hans , Asklund Camilla , Tommerup Niels , Jakobsen Linda P. 
Published: May 2008

AbstractPopliteal pterygium syndrome (PPS) and Van der Woude syndrome (VWS) are caused by mutations in the gene interferon regulatory factor 6 (IRF6). Skeletal, genital malformations and involvement of the skin occur in PPS and orofacial clefting and lip pits occur in both. We report on a patient with unilateral cleft lip and palate, ankyloblepharon, paramedian lip pits, unilateral renal aplasia, and a coronal hypospadias. By sequencing IRF6, we detected a novel missense mutation (Arg339Ile). The other family members were unaffected and had no IRF6 mutations, including the patient's brother who was also born with hypospadias. The patient and his brother were both conceived by in vitro fertilization (IVF). It is discussed whether the renal malformation in the patient is related to the IVF procedure or to the IRF6 mutation. © 2008 Wiley‐Liss, Inc.
Further case of microdeletion of 8q24 with phenotype overlapping Langer–Giedion without TRPS1 deletion
Authors: McBrien Jacqueline , Crolla John Anthony , Huang Shuwen , Kelleher Jerry , Gleeson John , Lynch Sally Ann 
Published: May 2008

AbstractLanger–Giedion syndrome results from a microdeletion at 8q24.1 encompassing the EXT1 and the adjacent TRPS1 gene. We report on a boy with an oligo array‐cgh characterized small microdeletion involving EXT1 alone but with some features of Langer–Giedion syndrome suggesting a functional disturbance of TRPS1. This boy, in addition to a mild Langer–Giedion like phenotype, also had some unusual features including prominent toe pads and fat pads on the soles of his feet similar to those described in Pierpont syndrome. © 2008 Wiley‐Liss, Inc.
Antimicrobial polyester
Authors: Ren Xuehong , Kocer Hasan B. , Kou Lei , Worley S. D. , Broughton R. M. , Tzou Y. M. , Huang T. S. 
Published: May 2008

AbstractTwo N‐halamine siloxane precursors, 5,5‐dimethyl‐3‐(3′‐triethoxysilylpropyl)hydantoin and 3‐(3′‐triethoxysilylpropyl)‐7,7,9,9‐tetramethyl‐1,3,8‐triazaspiro[4.5]decane‐2,4‐dione, have been synthesized and coated onto polyester fiber surfaces. The coated polyester was rendered biocidal after exposure to household bleach solution by converting the heterocyclic precursors to N‐halamine moieties. The thermal properties of these coated polyester samples were determined with differential scanning calorimetry. The chlorinated polyester swatches were challenged with Staphylococcus aureus (ATCC 6538) and Escherichia coli O157 : H7 (ATCC 43895) with contact times ranging from 1 to 30 min. The biocidal testing showed that the chlorinated samples inactivated S. aureus and E. coli O157 : H7 within 5 and 30 min of contact, respectively. Standard washing tests indicated that the chlorinated coated fibers were very resistant to loss of the coating through hydrolyses. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Initial results using GPS navigation with the Foerster magnetometer system at the World Heritage site of Cyrene, Libya
Authors: Gaffney Chris , Gaffney Vince , Cuttler Richard , Yorston Ron 
Published: May 2008

AbstractThis Short Report summarizes some initial results using real time GPS to navigate and collect magnetometer data using Foerster sensors and a magnetic cart. The Foerster system is primarily aimed at the detection of buried ordnance and, by comparison to some other magnetometer sensors, the reported sensitivity is relatively low. However, the sensors require no alignment in the field, nor does the system require a regular contiguous grid to be established across the survey area. The latter means that data grids of different sizes and orientation can be measured and stitched together as part of data restoration prior to processing. The accurate positioning of the data means that ‘staggering’, which is often seen in time‐based collection strategies, is not apparent in the data; overall less processing is required to produce a final image than is required for other fluxgate instruments. Data from a survey at Cyrene are reproduced to illustrate the strengths of the system. Copyright © 2008 John Wiley & Sons, Ltd.
Single‐cell microinjection technology in cell biology
Authors: Zhang Yan , Yu Long‐Chuan 
Published: May 2008

AbstractSingle‐cell microinjection has been successfully used to deliver exogenous proteins, cDNA constructs, peptides, drugs and particles into transfection‐challenged cells. With precisely controlled delivery dosage and timing, microinjection has been used in many studies of primary cultured cells, transgenic animal production, in vitro fertilization and RNA inference. This review discusses the advantages and limits of microinjection as a mechanical delivery method and its applications to attached and suspended cells. BioEssays 30:606–610, 2008. © 2008 Wiley Periodicals, Inc.
Heterochromatin tells CENP‐A where to go
Authors: Durand‐Dubief Mickaël , Ekwall Karl 
Published: May 2008

AbstractThe centromere is the region of the chromosome where the kinetochore forms. Kinetochores are the attachment sites for spindle microtubules that separate duplicated chromosomes in mitosis and meiosis. Kinetochore formation depends on a special chromatin structure containing the histone H3 variant CENP‐A. The epigenetic mechanisms that maintain CENP‐A chromatin throughout the cell cycle have been studied extensively but little is known about the mechanism that targets CENP‐A to naked centromeric DNA templates. In a recent report published in Science,1 such de novo centromere assembly of CENP‐A is shown to be dependent on heterochromatin and the RNA interference pathway. BioEssays 30:526–529, 2008. © 2008 Wiley Periodicals, Inc.
Using a meiosis detection toolkit to investigate ancient asexual “scandals” and the evolution of sex
Authors: Schurko Andrew M. , Logsdon John M. 
Published: May 2008

AbstractSexual reproduction is the dominant reproductive mode in eukaryotes but, in many taxa, it has never been observed. Molecular methods that detect evidence of sex are largely based on the genetic consequences of sexual reproduction. Here we describe a powerful new approach to directly search genomes for genes that function in meiosis. We describe a “meiosis detection toolkit”, a set of meiotic genes that represent the best markers for the presence of meiosis. These genes are widely present in eukaryotes, function only in meiosis and can be isolated by degenerate PCR. The presence of most, or all, of these genes in a genome would suggest they have been maintained for meiosis and, implicitly, sexual reproduction. In contrast, their absence would be consistent with the loss of meiosis and asexuality. This approach will help to understand both meiotic gene evolution and the capacity for meiosis and sex in putative obligate asexuals. BioEssays 30:579–589, 2008. © 2008 Wiley Periodicals, Inc.
Identification of Bacterial Carotenoid Cleavage Dioxygenase Homologues That Cleave the Interphenyl α,β Double Bond of Stilbene Derivatives via a Monooxygenase Reaction
Authors: Marasco Erinn K. , Schmidt‐Dannert Claudia 
Published: May 2008

AbstractCarotenoid cleavage oxygenases (CCOs), which are also referred to as carotenoid cleavage dioxygenases (CCDs) are a new class of nonheme iron‐type enzymes that oxidatively cleave double bonds in the conjugated carbon chain of carotenoids. The oxidative cleavage mechanism of these enzymes is not clear, and both monooxygenase and dioxygenase mechanisms have been proposed for different carotenoid cleavage enzymes. CCOs have been described from plants, animals, fungi, and cyanobacteria, but little is known about their distribution and activities in bacteria other than cyanobacteria. We surveyed bacterial genome sequences for CCO homologues and report the characterization of CCO homologues that were identified in Novosphingobium aromaticivorans DSM 12444 (NOV1 and NOV2) and in Bradyrhizobium sp. (BRA‐J and BRA‐S). In vitro and in vivo assays with carotenoid and stilbene compounds were used to investigate the cleavage activities of the recombinant enzymes. The NOV enzymes cleaved the interphenyl α‐β double bond of stilbenes that had an oxygen functional group at the 4′ carbon atom (e.g., resveratrol, piceatannol, and rhaponticin) to the corresponding aldehyde products. Carotenoids and apocarotenoids were not substrates for these enzymes. The two homologous enzymes from Bradyrhizobium sp. did not possess carotenoid or stilbene cleavage oxygenase activities, but showed activity with farnesol. To investigate whether the oxidative cleavage of stilbenes proceeds via a monooxygenase or dioxygenase reaction, oxygen‐labeling studies were conducted with NOV2. Our labeling studies show that the double‐bond cleavage of stilbenes occurs via a monooxygenase reaction mechanism.