bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationships between quartz weathering and soil type (Entisol, Inceptisol and Alfisol) in Sierra Nevada (southeast Spain)
Authors: Martín‐García J. M. , Márquez R. , Delgado G. , Sánchez‐Marañón M. , Delgado R. 
Published: December 2014

SummaryQuartz was studied in a soil development sequence of Entisol‐Inceptisol‐Alfisol in a Mediterranean mountain climate on a metamorphic quartz‐rich substrate, using scanning electron microscopy (SEM), energy dispersive X‐ray (EDX) and backscattered electron (BSE) and electron microprobes (EMP), with fine sand (250–50 µm) as the selected particle‐size fraction. The quartz in the soil is inherited mainly from the parent rock. However, a study of the surface characteristics of the quartz grains and measurement of non‐Si elements (Al3+, Ti4+, Fe3+, Na+, K+, Mg2+ and Ca2+), both near‐edge and in the centre of grains, showed that the quartz is altered substantially in the progression parent rock < Entisol < Inceptisol < Alfisol, and in the A, AC and Bt horizons rather than in the C horizon. In all profiles and horizons the content of non‐Si elements was greater in the near‐edge zones than in the centre of the grain. This pedochemical process thus operates mainly at the surface of the grain and results in a variety of pits, fissures and other corrosion features (hole or corrosion gulf, opening of inter‐granular surfaces, areal alteration, smoothing of edges of conchoidal fractures, and deepening of incisions of conchoidal fractures). Estimation of the W index, which assesses the intensity of the weathering process from the size and density of the etch pits, revealed that many of the quartz grains had alterations somewhat similar to the quartzes of tropical soils. This study casts doubt on the paradigm of quartz inalterability in soils of little to medium pedological change in temperate zones.
Glomalin‐related soil protein in French temperate forest soils: interference in the Bradford assay caused by co‐extracted humic substances
Authors: Jorge‐Araújo P. , Quiquampoix H. , Matumoto‐Pintro P. T. , Staunton S. 
Published: December 2014

SummaryThermostable soil protein, known as glomalin, is an important component of soil carbon stocks. Thought to originate from endomycorrhizal fungi, Glomales, this operationally‐defined fraction of soil organic matter contains proteins of diverse origin as well as non‐protein material, including humic substances. Accumulation results from the balance between production/release and subsequent degradation. Quantification of the protein is subject to uncertainty because of the co‐extraction of other components that interfere with the Bradford assay. We studied 10 topsoils from French temperate forests, taken from the national forest monitoring network (Renecofor). Two fractions were extracted, easily extractable (EE) at neutral pH and total extractable (T) at pH 8. Protein was quantified with the colorimetric Bradford method, either by direct calibration using bovine serum albumin (BSA) or by extrapolation of the standard addition plot of BSA. Solubilized organic matter was characterized by using absorbance at 465 and 665 nm and by three‐dimensional fluorescence excitation‐emission spectroscopy. Neither soil properties nor forest cover influenced glomalin‐related soil protein (GRSP) content. Direct assay gave the GRSPEE to be about 1 g kg−1 soil, and GRSPT in the range 3–10 g kg−1, accounting for about 2% of soil organic carbon and about 15% of soil nitrogen. Standard addition plots indicated a two to sixfold under‐estimation of protein in total extracts, caused by negative interference with the Bradford assay. The GRSPEE was correlated significantly with both estimates of GRSPT. Under‐estimation of GRSPT by direct assay was not related to the E4:E6 ratio but was correlated significantly with the intensity of absorbance at either 460 or 660 nm and with one of the fluorescence peaks. We conclude that GRSPEE is not necessarily more recent than GRSPT and that both fractions may be probes of protein content, but that absolute contents may be under‐estimated because of co‐extracted humic substances.
Pathogenic EFHC1 mutations are tolerated in healthy individuals dependent on reported ancestry
Authors: Subaran Ryan L. , Conte Juliette M. , Stewart William C. L. , Greenberg David A. 
Published: December 2014

SummaryObjectiveScreening for specific coding mutations in the EFHC1 gene has been proposed as a means of assessing susceptibility to juvenile myoclonic epilepsy (JME). To clarify the role of these mutations, especially those reported to be highly penetrant, we sought to measure the frequency of exonic EFHC1 mutations across multiple population samples.MethodsTo find and test variants of large effect, we sequenced all EFHC1 exons in 23 JME and 23 non‐JME idiopathic generalized epilepsy (IGE) Hispanic patients, and 60 matched controls. We also genotyped specific EFHC1 variants in IGE cases and controls from multiple ethnic backgrounds, including 17 African American IGE patients, with 24 matched controls, and 92 Caucasian JME patients with 103 matched controls. These variants are reported to be pathogenic, but are also found among unphenotyped individuals in public databases. All subjects were from the New York City metro area and all controls were required to have no family history of seizures.ResultsWe found the reportedly pathogenic EFHC1 P77T‐R221H (rs149055334‐rs79761183) JME haplotype in one Hispanic control and in two African American controls. Public databases also show that the EFHC1 P77T‐R221H JME haplotype is present in unphenotyped West African ancestry populations, and we show that it can be found at appreciable frequency in healthy individuals with no family history of epilepsy. We also found a novel splice‐site mutation in a single Hispanic JME patient, the effect of which is unknown.SignificanceOur findings raise questions about the effect of reportedly pathogenic EFHC1 mutations on JME. One intriguing possibility is that some EFHC1 mutations may be pathogenic only when introduced into specific genetic backgrounds. By focusing on data from multiple populations, including the understudied Hispanic and Black/African American populations, our study highlights that for complex traits like JME, the body of evidence necessary to infer causality is high.
Interactive creep–fatigue crack growth of 2024‐T3 Al sheets: selective transitional functions
Authors: Tang K. K. , Li S. H. 
Published: December 2014

AbstractInteractive creep–fatigue on aeronautical materials has been of a great concern to engineers and researchers. There are still more fundamental issues to be addressed. In this regard, 2024‐T3 Al sheets are considered to study the transitional behaviours that incorporatematerial, loading and geometry effects in the interactive creep–fatigue process. A dual‐scale fatigue crack growth da/dN‐ΔS model that includes microscale, macroscale and large scales is proposed based on the volume energy density criterion. The model generates the transitionalised crack length (TCL) compared with the fictitious crack length (FCL) yielded from the da/dN‐ΔK model that is only restricted to monoscaling. Crossover points are observed across TCL and FCL curves. With stress amplitude being fixed, three levels of mean stress are employed to discuss the variational effects of transitional functions (TFs). Applied loading conditions have an appreciable effect on the fatigue life cycles of 2024‐T3 Al sheets. Variation of R ratios leads to the interactive creep–fatigue behaviour and further enforces the selective TFs in the inherent multiscaling process. TCLs and FCLs are compared with test data of the 2024‐T3 Al sheet. Rationality and superiority of the dual‐scale crack growth model are validated.
Local adaptation and embryonic plasticity affect antipredator traits in hatchling pond snails
Authors: Dalesman Sarah , Thomas Angharad , Rundle Simon D. 
Published: December 2014

Summary

The biology of induced defences in very early life history stages is poorly understood in freshwater invertebrates, but may be equally, if not more, important than later stages in influencing population dynamics and survival. Here, we investigated how exposure of embryos of the pond snail Lymnaea stagnalis to predator kairomones altered traits associated with protection (crawl out behaviour and shell size) in hatchling snails. We also investigated whether levels of plasticity were influenced by habitat of origin by comparing reaction norms from sites with different levels of predation risk: three high risk (predatory fish present) and three low risk (predatory fish absent).

F2 embryos from snails from each population were exposed to kairomones from a predatory fish (Tinca tinca) or control conditions for their entire development up to the point of hatching. Their avoidance behaviour and size (spire height) were then measured 1 day and 7 days after hatching.

One day post‐hatching, levels of predator avoidance, primarily time spent at the water line, were significantly greater in high‐risk versus low‐risk populations; however, avoidance was also increased in hatchling snails exposed to predator cues as embryos, compared with those developing in control conditions. Snails exposed to predator cues during development were smaller, and there was a strong negative relationship between size and avoidance behaviour, suggesting a trade‐off or trait compensation between growth and behaviour.

At 7 days post‐hatching, a similar pattern in avoidance behaviour was found, with increased avoidance in snails from high‐risk habitats and in those exposed to predator kairomones during their development. The primary avoidance response switched to crawling above the waterline at 7 days post‐hatching. There was no significant difference in shell size between treatments, suggesting that predator‐exposed snails had exhibited ‘catch‐up’ growth. This enhanced investment in growth between 1 day and 7 days post‐hatching was positively correlated with elevated avoidance behaviour across treatment groups, demonstrating that snails switched to trait co‐specialisation of defence traits.

During the first few days post‐hatching, snails alter the type of avoidance behaviour and also the relationship between morphological and behavioural defence traits. The degree of expression of these defensive traits in hatchling snails is influenced by both their developmental environment and local adaptation to their predation habitat that may have large implications for survival.
Directionality of recent bird distribution shifts and climate change in Great Britain
Authors: Gillings Simon , Balmer Dawn E. , Fuller Robert J. 
Published: December 2014

AbstractThere is good evidence that species' distributions are shifting poleward in response to climate change and wide interest in the magnitude of such responses for scientific and conservation purposes. It has been suggested from the directions of climatic changes that species' distribution shifts may not be simply poleward, but this has been rarely tested with observed data. Here, we apply a novel approach to measuring range shifts on axes ranging through 360°, to recent data on the distributions of 122 species of British breeding birds during 1988–1991 and 2008–2011. Although previously documented poleward range shifts have continued, with an average 13.5 km shift northward, our analysis indicates this is an underestimate because it ignores common and larger shifts that occurred along axes oriented to the north‐west and north‐east. Trailing edges contracted from a broad range of southerly directions. Importantly, these results are derived from systematically collected data so confounding observer‐effort biases can be discounted. Analyses of climate for the same period show that whilst temperature trends should drive species along a north–north‐westerly trajectory, directional responses to precipitation will depend on both the time of year that is important for determining a species' distribution, and the location of the range margin. Directions of species' range centroid shift were not correlated with spatial trends in any single climate variable. We conclude that range shifts of British birds are multidirectional, individualistic and probably determined by species‐specific interactions of multiple climate factors. Climate change is predicted to lead to changes in community composition through variation in the rates that species' ranges shift; our results suggest communities could change further owing to constituent species shifting along different trajectories. We recommend more studies consider directionality in climate and range dynamics to produce more appropriate measures of observed and expected responses to climate change.
Snowpack, fire, and forest disturbance: interactions affect montane invasions by non‐native shrubs
Authors: Stevens Jens T. , Latimer Andrew M. 
Published: December 2014

AbstractMontane regions worldwide have experienced relatively low plant invasion rates, a trend attributed to increased climatic severity, low rates of disturbance, and reduced propagule pressure relative to lowlands. Manipulative experiments at elevations above the invasive range of non‐native species can clarify the relative contributions of these mechanisms to montane invasion resistance, yet such experiments are rare. Furthermore, global climate change and land use changes are expected to cause decreases in snowpack and increases in disturbance by fire and forest thinning in montane forests. We examined the importance of these factors in limiting montane invasions using a field transplant experiment above the invasive range of two non‐native lowland shrubs, Scotch broom (Cytisus scoparius) and Spanish broom (Spartium junceum), in the rain–snow transition zone of the Sierra Nevada of California. We tested the effects of canopy closure, prescribed fire, and winter snow depth on demographic transitions of each species. Establishment of both species was most likely at intermediate levels of canopy disturbance, but at this intermediate canopy level, snow depth had negative effects on winter survival of seedlings. We used matrix population models to show that an 86% reduction in winter snowfall would cause a 2.8‐fold increase in population growth rates in Scotch broom and a 3.5‐fold increase in Spanish broom. Fall prescribed fire increased germination rates, but decreased overall population growth rates by reducing plant survival. However, at longer fire return intervals, population recovery between fires is likely to keep growth rates high, especially under low snowpack conditions. Many treatment combinations had positive growth rates despite being above the current invasive range, indicating that propagule pressure, disturbance, and climate can all strongly affect plant invasions in montane regions. We conclude that projected reductions in winter snowpack and increases in forest disturbance are likely to increase the risk of invasion from lower elevations.
Response of wheat growth, grain yield and water use to elevated CO2 under a Free‐Air CO2 Enrichment (FACE) experiment and modelling in a semi‐arid environment
Authors: O'Leary Garry J. , Christy Brendan , Nuttall James , Huth Neil , Cammarano Davide , Stöckle Claudio , Basso Bruno , Shcherbak Iurii , Fitzgerald Glenn , Luo Qunying , Farre‐Codina Immaculada , Palta Jairo , Asseng Senthold 
Published: December 2014

AbstractThe response of wheat crops to elevated CO2 (eCO2) was measured and modelled with the Australian Grains Free‐Air CO2 Enrichment experiment, located at Horsham, Australia. Treatments included CO2 by water, N and temperature. The location represents a semi‐arid environment with a seasonal VPD of around 0.5 kPa. Over 3 years, the observed mean biomass at anthesis and grain yield ranged from 4200 to 10 200 kg ha−1 and 1600 to 3900 kg ha−1, respectively, over various sowing times and irrigation regimes. The mean observed response to daytime eCO2 (from 365 to 550 μmol mol−1 CO2) was relatively consistent for biomass at stem elongation and at anthesis and LAI at anthesis and grain yield with 21%, 23%, 21% and 26%, respectively. Seasonal water use was decreased from 320 to 301 mm (P = 0.10) by eCO2, increasing water use efficiency for biomass and yield, 36% and 31%, respectively. The performance of six models (APSIM‐Wheat, APSIM‐Nwheat, CAT‐Wheat, CROPSYST, OLEARY‐CONNOR and SALUS) in simulating crop responses to eCO2 was similar and within or close to the experimental error for accumulated biomass, yield and water use response, despite some variations in early growth and LAI. The primary mechanism of biomass accumulation via radiation use efficiency (RUE) or transpiration efficiency (TE) was not critical to define the overall response to eCO2. However, under irrigation, the effect of late sowing on response to eCO2 to biomass accumulation at DC65 was substantial in the observed data (~40%), but the simulated response was smaller, ranging from 17% to 28%. Simulated response from all six models under no water or nitrogen stress showed similar response to eCO2 under irrigation, but the differences compared to the dryland treatment were small. Further experimental work on the interactive effects of eCO2, water and temperature is required to resolve these model discrepancies.
Effects of alkaloids from fungal endophytes in grass–Epichloëassociations on survival of the sorghum plant bug (Stenotus rubrovittatus)
Authors: Shiba Takuya , Arakawa Akira , Sugawara Koya 
Published: December 2014

AbstractEpichloë(Neotyphodium) endophytes are symbiotic fungi in association with gramineous plants and produce a range of alkaloids that enhance the resistance of host plants to insect pests.N‐formylloline, one of theEpichloë‐produced alkaloids, is known to be toxic to some insects but not to mammals. Therefore,Epichloë‐infected grasses with highN‐formylloline concentrations are expected to reduce the population of some insect pests in meadows. To assess the adverse effects ofN‐formylloline on the survival of the sorghum plant bug (Stenotus rubrovittatus) known as a major pest, artificial feeding ofN‐formylloline through feeding sachets was carried out.N‐formylloline reduced the survival ofS. rubrovittatus, even at 50 ppm, which was considerably lower than the concentrations in mostEpichloë‐infected grasses. The results suggest thatN‐formylloline inEpichloë‐infected grasses can reduce the population ofS. rubrovittatusin meadows.
Late acceleration of glomerular filtration rate decline is a risk for hemodialysis catheter use in patients with established nephrology chronic kidney disease care
Authors: Chin Andrew I. , Nguyen Tuan A. , Dinesh Kumar P. , Morfin José A. 
Published: December 2014

AbstractChronic kidney disease (CKD) patients with established nephrology care have a high rate of tunneled dialysis catheters (TDC) as first vascular access when transitioning to hemodialysis (HD). We sought to identify factors associated with this problem. Patients who started HD and had prior CKD care within our renal clinic were categorized according to access type at incident HD. Clinical factors, all estimated glomerular filtration rates (eGFR), renal clinic attendance records, hospital admissions in the 6 months preceding HD start, and patient participation in predialysis education course were analyzed. Three hundred thirty‐eight patients initiated HD, 107 received pre‐HD CKD care within our clinics. Seventy patients started with a TDC. All groups started HD at similar eGFR values. The trajectory of eGFR decline in the 6 months prior to HD start was significantly more rapid in the TDC group. Patients in the TDC group had more acute health events in the prior 6 months. Multivariate modeling showed that failure to attend a predialysis education course and having a more rapid rate of eGFR decline in the 6 months prior to dialysis initiation were both associated with TDC use. Patients with CKD nephrology care who initiated HD with a TDC as first vascular access had a more rapid rate of decline in eGFR in the months preceding dialysis start and were less likely to have attended our predialysis education course. This appears to correspond with the observed increased number of emergency and hospital visits in the 6 months prior to end‐stage renal disease.
Development of a patient‐centred, patient‐reported outcome measure (PROM) for post‐stroke cognitive rehabilitation: qualitative interviews with stroke survivors to inform design and content
Authors: Patchick Emma L. , Horne Maria , Woodward‐Nutt Kate , Vail Andy , Bowen Audrey 
Published: December 2014

AbstractBackgroundImproving cognition is service users' top research priority for life after stroke, and future research should include outcomes that they deem important. Patient perspectives on outcomes are collected using patient‐reported outcome measures (PROMs). There is currently no patient‐centred PROM specific for cognitive rehabilitation trials.ObjectiveInform PROM development by exploring stroke survivor perspectives on the important, measurable impacts of persisting post‐stroke cognitive problems.DesignQualitative semi‐structured interviews in participants' homes.ParticipantsPurposive sample of 16 cognitively impaired stroke survivors at least six months post‐stroke.MethodsInterviews used a schedule and communication aids developed through patient consultation. Interviews were transcribed verbatim with non‐verbal communication recorded using field notes. Data were analysed using a framework approach to find commonalities to shape the focus and content of an outcome measure.ResultsParticipants identified important impacts of their ‘invisible’ cognitive problems, outside of other stroke‐related impairments. Cognitive problems exacerbated emotional issues and vice versa. Changes in self‐identity and social participation were prominent. Impact was not spoken about in terms of frequency but rather in terms of the negative affect associated with problems; terms like ‘bothered’ and ‘frustration’ were often used.ConclusionsThe results support the development of a PROM specifically designed to address the impact of cognitive problems. It should:

include items addressing a comprehensive range of cognitive skills;

ask questions about mood, self‐identity and social participation;

use accessible wording that respondents understand and endorse;

measure impact rather than frequency; and

explore perceived impact on carers.
Comparative experimental subcutaneous glanders and melioidosis in the common marmoset (Callithrix jacchus)
Authors: Nelson Michelle , Salguero Francisco J. , Dean Rachel E. , Ngugi Sarah A. , Smither Sophie J. , Atkins Timothy P. , Lever Mark S. 
Published: December 2014

SummaryGlanders and melioidosis are caused by two distinct Burkholderia species and have generally been considered to have similar disease progression. While both of these pathogens are HHS/CDC Tier 1 agents, natural infection with both these pathogens is primarily through skin inoculation. The common marmoset (Callithrix jacchus) was used to compare disease following experimental subcutaneous challenge. Acute, lethal disease was observed in marmosets following challenge with between 26 and 1.2 × 108 cfu Burkholderia pseudomallei within 22–85 h. The reproducibility and progression of the disease were assessed following a challenge of 1 × 102 cfu of B. pseudomallei. Melioidosis was characterised by high levels of bacteraemia, focal microgranuloma progressing to non‐necrotic multifocal solid lesions in the livers and spleens and multi‐organ failure. Lethal disease was observed in 93% of animals challenged with Burkholderia mallei, occurring between 5 and 10.6 days. Following challenge with 1 × 102 cfu of B. mallei, glanders was characterised with lymphatic spread of the bacteria and non‐necrotic, multifocal solid lesions progressing to a multifocal lesion with severe necrosis and pneumonia. The experimental results confirmed that the disease pathology and presentation is strikingly different between the two pathogens. The marmoset provides a model of the human syndrome for both diseases facilitating the development of medical countermeasures.