bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incorporating model complexity and spatial sampling bias into ecological niche models of climate change risks faced by 90 California vertebrate species of concern
Authors: Warren Dan L. , Wright Amber N. , Seifert Stephanie N. , Shaffer H. Bradley 
Published: December 2013

AbstractAimEcological niche models are increasingly being used to aid in predicting the effects of future climate change on species distributions. Complex models that show high predictive performance on current distribution data may do a poor job of predicting new data due to overfitting. In addition, model performance is often evaluated using techniques that are sensitive to spatial sampling bias. Here, we explore the effects of model complexity and spatial sampling bias on niche models for 90 vertebrate taxa of conservation concern.LocationCalifornia, USA.MethodsWe used Akaike information criterion (AICc) to select variables and tune Maxent's built‐in regularization parameter (β) to constrain model complexity. In addition, we incorporated several estimates of spatial sampling bias based on interpolations of target group data. Ensemble forecasts were developed for future conditions from two emission scenarios and three climate change models for the year 2050.ResultsReducing the number of predictors and tuning β resulted in a reduction in the number of parameters in models built with sample sizes greater than approximately 10 occurrence points. Reducing the number of predictors had a substantially higher impact on the relative prioritization of different grid cells than did increasing regularization. There was little difference in prioritization of habitat when comparing models built using different spatial sampling bias estimates. Over half of the taxa were predicted to experience >80% reductions in environmental suitability in currently occupied cells, and this pattern was consistent across taxonomic groups.Main ConclusionsOur results demonstrate that reducing the number of correlated predictor variables tends to decrease the breadth of models, while tuning regularization using AICc tends to increase it. These two strategies may provide a reasonable bracketing strategy for assessing climate change impacts.
Field margin vegetation enhances biological control and crop damage suppression from multiple pests in organic tomato fields
Authors: Balzan Mario V. , Moonen Anna‐Camilla 
Published: December 2013

AbstractEphemeral cropping systems are characterized by frequent disturbances of ecological processes, which may compromise the conservation of plant and arthropod diversity and the ecosystem services they may provide. Conservation biological control practices include habitat manipulations that provide non‐pest resources and selectively enhance natural enemies' effectiveness. This study, conducted in eight commercial fields of organically grown tomato, compared the effectiveness of sown flower strips with semi‐natural margins in regulating natural enemy abundance, biocontrol, and crop damage. During repeated visits, the abundance of different arthropod groups was recorded. Crop surveys included measurement of aphid abundance, parasitism, and leaf and fruit damage from sap‐sucking and lepidopteran pests. Semi‐natural habitats were associated with higher vegetation diversity, but natural enemies were more strongly associated with sown strips during flowering. Sap‐sucking pests were always recorded in higher abundance in flower strips, but crop damage in the plots adjacent to these strips was lower, suggesting that these strips may act as a trap‐crop. The inclusion of floral supplements enhanced the parasitism rate of aphids in the crop, and reduced the rate of increase of lepidopteran‐caused foliar damage with time. Early in the growing season, semi‐natural strips showed significantly lower levels of crop damage and aphid counts, suggesting that these habitats may be important during early crop colonization by natural enemies. These results indicate that the inclusion of flower strips enhances the conservation of arthropod functional diversity in ephemeral crops, and that diverse mechanisms are important for controlling different pests. However, the efficacy of habitat manipulation is likely to be greater when it is complemented with the conservation of diverse semi‐natural vegetation in the pre‐existing field margin.
Emigration and mortality of juvenile brown trout in aNewZealand headwater tributary
Authors: Holmes Robin , Hayes John W. , Jiang Weimin , Quarterman Aaron , Davey Lawson N. 
Published: December 2013

AbstractWe investigated juvenile brown trout migration and mortality in a headwater tributary of theMotuekaRiver,NewZealand, by tracking 1000 young‐of‐the‐year passive integrated transponder (PIT) tagged fish over autumn to summer to (i) partition total loss into emigration and mortality and (ii) determine the influence of season and flow on emigration. Fish were tracked using mobile and fixedPITtag readers. Of the 1000 fish tagged, 173 remained within theRainyRiver; emigration contributed 60% and mortality 29% to loss. Only 11% of fish tagged in autumn were predicted to remain in the upper reaches of the stream by early summer, and this agreed with density data collected in a parallel study. We identified a two‐phase downstream migration pattern with early movement of large young‐of‐the‐year fish in autumn (mainly during floods). This was followed by another substantial period of movement in spring (during floods and lower flows) by fish that were initially smaller at the time ofPITtagging. The management implications for damming and fish screening in headwater tributaries are discussed.
Rapid and persistent impairments of the forelimb motor representations following cervical deafferentation in rats
Authors: Jiang Yu‐Qiu , Williams Preston T. J. A. , Martin John H. 
Published: December 2013

AbstractSkilled motor control is regulated by the convergence of somatic sensory and motor signals in brain and spinal motor circuits. Cervical deafferentation is known to diminish forelimb somatic sensory representations rapidly and to impair forelimb movements. Our focus was to determine what effect deafferentation has on the motor representations in motor cortex, knowledge of which could provide new insights into the locus of impairment following somatic sensory loss, such as after spinal cord injury or stroke. We hypothesized that somatic sensory information is important for cortical motor map topography. To investigate this we unilaterally transected the dorsal rootlets in adult rats from C4 to C8 and mapped the forelimb motor representations using intracortical microstimulation, immediately after rhizotomy and following a 2‐week recovery period. Immediately after deafferentation we found that the size of the distal representation was reduced. However, despite this loss of input there were no changes in motor threshold. Two weeks after deafferentation, animals showed a further distal representation reduction, an expansion of the elbow representation, and a small elevation in distal movement threshold. These changes were specific to the forelimb map in the hemisphere contralateral to deafferentation; there were no changes in the hindlimb or intact‐side forelimb representations. Degradation of the contralateral distal forelimb representation probably contributes to the motor control deficits after deafferentation. We propose that somatic sensory inputs are essential for the maintenance of the forelimb motor map in motor cortex and should be considered when rehabilitating patients with peripheral or spinal cord injuries or after stroke.
Risk of non‐melanoma skin cancer in myasthenia patients treated with azathioprine
Authors: Pedersen E. G. , Pottegård A. , Hallas J. , Friis S. , Hansen K. , Jensen P. E. H. , Gaist D. 
Published: December 2013

Background and purposeThe association between use of azathioprine and risk of non‐melanoma skin cancer (NMSC) in patients with myasthenia was evaluated in a nationwide setting. Treatment of autoimmune myasthenia frequently involves long‐term exposure to immunosuppressants, including azathioprine. Use of azathioprine increases the risk of NMSC in organ recipients and probably also in patients with other autoimmune disorders. No previous study has specifically investigated the risk of NMSC in myasthenia patients treated with azathioprine.MethodsThis is a case–control study based on Danish population‐based registries. Cases were myasthenia patients with a first time diagnosis of NMSC during 2004–2009. Age‐ and sex‐matched controls were selected amongst myasthenia patients with no history of cancer using incidence density sampling. Prior use of azathioprine in cases and controls was assessed through prescription records (1995–2009). Conditional logistic regression was used to calculate odds ratios (OR) with 95% confidence intervals (CI) for skin cancer associated with a high cumulative dose (≥150 g) or long‐term use (≥5 years) of azathioprine, adjusted for confounders.ResultsThirty NMSC cases and 360 matched controls were identified. Ever use of azathioprine was associated with a considerably increased risk of NMSC (OR 3.3, 95% CI 1.5–7.3) that was even more apparent in patients with high cumulative dose (OR 4.6, 95% CI 1.7–12.5) or long‐term (OR 4.8; 95% CI 1.7–13.6) use of azathioprine.ConclusionAzathioprine use in patients with myasthenia is associated with an increased risk of NMSC.
Evidence for iron‐regulated cyanobacterial predominance in oligotrophic lakes
Authors: Sorichetti Ryan J. , Creed Irena F. , Trick Charles G. 
Published: December 2013

Summary

Cyanobacterial harmful algal blooms (cyanoHABs) are most often associated with large eutrophic lakes. In the past decade, an increase in the incidence of cyanoHABs in small oligotrophic lakes within the Laurentian Great Lakes‐St. Lawrence River Basin has been documented. We explored macro‐ and micronutrient conditions during peak phytoplankton biomass that result in high cyanobacterial densities.

We hypothesised that the availability of biologically available iron (Fe) both limits the assimilation of phosphorus by competing taxa and selects for the predominance of cyanobacteria.

We tested this hypothesis with a comparative study of 25 oligotrophic lakes in central Ontario, Canada. These lakes were sampled during peak phytoplankton biomass for 3 years (from 2009 to 2011) for concentrations of total phosphorus (TP), total nitrogen (TN), ammonium (), nitrate (), total dissolved Fe (TDFe) and pH for comparison with phytoplankton community biomass and composition.

Correlation analyses indicated that predominance of cyanobacteria was assured at all TP levels when the availability of Fe was low. Proportionally high cyanobacterial density occurred at relatively low TP in lakes with a molar ratio of dissolved inorganic N (DIN):TP of 8:1 and a modelled ferric Fe concentration <1.0 × 10−19 m at which cyanobacteria have been shown to be competitive for Fe in laboratory experiments. Regression tree analysis confirmed the minimal influence of P and N, implying that cyanobacteria thrive in low Fe environments.

Our findings suggest that an increased susceptibility of oligotrophic lakes to cyanobacterial bloom formation is based on the presence of cyanobacteria that have adapted sufficiently to low Fe environments and are able to multiply rapidly when pulses of P are made available to the ecosystem. Physiologically prepared transitionary cyanobacteria do not have to compete with the eukaryotic species but rather exploit the new P and replicate faster.
Controls of dissolved organic matter quality: evidence from a large‐scale boreal lake survey
Authors: Kothawala Dolly N. , Stedmon Colin A. , Müller Roger A. , Weyhenmeyer Gesa A. , Köhler Stephan J. , Tranvik Lars J. 
Published: December 2013

AbstractInland waters transport large amounts of dissolved organic matter (DOM) from terrestrial environments to the oceans, but DOM also reacts en route, with substantial water column losses by mineralization and sedimentation. For DOM transformations along the aquatic continuum, lakes play an important role as they retain waters in the landscape allowing for more time to alter DOM. We know DOM losses are significant at the global scale, yet little is known about how the reactivity of DOM varies across landscapes and climates. DOM reactivity is inherently linked to its chemical composition. We used fluorescence spectroscopy to explore DOM quality from 560 lakes distributed across Sweden and encompassed a wide climatic gradient typical of the boreal ecozone. Six fluorescence components were identified using parallel factor analysis (PARAFAC). The intensity and relative abundance of these components were analyzed in relation to lake chemistry, catchment, and climate characteristics. Land cover, particularly the percentage of water in the catchment, was a primary factor explaining variability in PARAFAC components. Likewise, lake water retention time influenced DOM quality. These results suggest that processes occurring in upstream water bodies, in addition to the lake itself, have a dominant influence on DOM quality. PARAFAC components with longer emission wavelengths, or red‐shifted components, were most reactive. In contrast, protein‐like components were most persistent within lakes. Generalized characteristics of PARAFAC components based on emission wavelength could ease future interpretation of fluorescence spectra. An important secondary influence on DOM quality was mean annual temperature, which ranged between −6.2 and +7.5 °C. These results suggest that DOM reactivity depends more heavily on the duration of time taken to pass through the landscape, rather than temperature. Projected increases in runoff in the boreal region may force lake DOM toward a higher overall amount and proportion of humic‐like substances.
Mechanistic insights into the effects of climate change on larval cod
Authors: Kristiansen Trond , Stock Charles , Drinkwater Kenneth F. , Curchitser Enrique N. 
Published: December 2013

AbstractUnderstanding the biophysical mechanisms that shape variability in fisheries recruitment is critical for estimating the effects of climate change on fisheries. In this study, we used an Earth System Model (ESM) and a mechanistic individual‐based model (IBM) for larval fish to analyze how climate change may impact the growth and survival of larval cod in the North Atlantic. We focused our analysis on five regions that span the current geographical range of cod and are known to contain important spawning populations. Under the SRES A2 (high emissions) scenario, the ESM‐projected surface ocean temperatures are expected to increase by >1 °C for 3 of the 5 regions, and stratification is expected to increase at all sites between 1950–1999 and 2050–2099. This enhanced stratification is projected to decrease large (>5 μm ESD) phytoplankton productivity and mesozooplankton biomass at all 5 sites. Higher temperatures are projected to increase larval metabolic costs, which combined with decreased food resources will reduce larval weight, increase the probability of larvae dying from starvation and increase larval exposure to visual and invertebrate predators at most sites. If current concentrations of piscivore and invertebrate predators are maintained, larval survival is projected to decrease at all five sites by 2050–2099. In contrast to past observed responses to climate variability in which warm anomalies led to better recruitment in cold‐water stocks, our simulations indicated that reduced prey availability under climate change may cause a reduction in larval survival despite higher temperatures in these regions. In the lower prey environment projected under climate change, higher metabolic costs due to higher temperatures outweigh the advantages of higher growth potential, leading to negative effects on northern cod stocks. Our results provide an important first large‐scale assessment of the impacts of climate change on larval cod in the North Atlantic.
The use of 185 MBq and 740 MBq of 153‐samarium hydroxyapatite for knee synovectomy in haemophilia
Authors: Calegaro J. U. M. , Machado J. , Furtado R. G. , de Almeida J. S. C. , de Vasconcelos A. V. P. , de Barboza M. F. , de Paula A. P. 
Published: December 2013

SummaryThe penetration of beta energy of 153‐samarium (153Sm) (0.8 MeV) is not only appropriate for synovectomy of median articulations but is possible to improve the radiobiological effect using increased activities. The aim of this study was to assess the effectiveness of 185 MBq and 740 MBq of 153‐samarium hydroxyapatite (153Sm‐HA) in knees of haemophilic patients. Thirty‐one patients – 36 knees, 30 males, were divided into two groups without coinjection of corticosteroid: A – 14 patients (17 knees) treated with intra‐articular dose of 185 MBq of 153Sm‐HA, average age 23 years; B – 17 patients (19 knees) with 740 MBq of 153Sm‐HA, average age 21.3 years. The evaluation before and after 1 year of synovectomy used the following criteria: reduction in the number of haemarthroses and use of the coagulation factor and improvement in articular motility. Adverse‐effects occurrence was considered too. Early and late scintigraphic studies were performed after synoviorthesis and no joint immobilization was recommended. The reduction in haemarthrosis and use of coagulation factor were: group 1 – 31.3% and 25%; group 2 – 81.5% and 79% with P < 0.001 respectively; no significant improvement in knees motility was noted for both groups. Four cases of mild reactional synovitis were observed in each group. The scintigraphic control showed homogenous distribution of the radiopharmaceuticals with no articular escape; the material was considered safe by its permanence in the articulation. We have significant improvement in the synovectomy of haemophilic knees with 740 MBq of 153Sm‐HA; the less penetration of its beta radiation was compensated by the increased biological effect with the higher used activity.
Chinese Hemophilia Joint Health Score 2.1 reliability study
Authors: Sun J. , Hilliard P. E. , Feldman B. M. , Zourikian N. , Chen L. , Blanchette V. S. , Luke K. H. , Poon M‐C. 
Published: December 2013

SummaryTo meet the rapidly expanding need for musculoskeletal (MSK) specialists [physiotherapists (PTs), physiatrists] in haemophilia care in China, a 4‐day Train the Trainer workshop was conducted in July/August 2009 in Beijing. A key focus was to train the participants to administer the Hemophilia Joint Health Score (HJHS) version 2.1 for effectively evaluating the MSK health of boys <18 years of age with haemophilia. The aim of this study was to test the HJHS version 2.1 inter‐ and intra‐rater reliability in a group of Chinese PTs and physiatrists with limited experience in haemophilia care. Each of the trained Chinese physiatrists and PTs examined eight boys 4–17 years old with moderate and severe haemophilia on day 1 and repeated the examination on the same patients the next day using the HJHS version 2.1. The boys had a wide range of target joint involvement and arthropathy. The HJHS score sheet, work sheets and manual had been translated into simple Chinese prior to the study. The interrater (ICC 0.90) and intra‐rater (ICC 0.91) reliability was excellent. The internal consistency of the HJHS items was also excellent with Cronbach's alpha of 0.86. With basic training in the administration of the HJHS version 2.1, the tool was reliably administered by Chinese PTs and physiatrists with limited haemophilic experience.
Congenital factor XIII deficiency in Pakistan: characterization of seven families and identification of four novel mutations
Authors: Borhany M. , Handrkova H. , Cairo A. , Schroeder V. , Fatima N. , Naz A. , Amanat S. , Shamsi T. , Peyvandi F. , Kohler H. P. 
Published: December 2013

SummaryDeficiency of coagulation factor XIII (FXIII) belongs to the rare bleeding disorders and its incidence is higher in populations with consanguineous marriages. The aims of this study were to characterize
patients and relatives from seven families with suspected FXIII deficiency from Pakistan and to identify the underlying mutations. As a first indicator of FXIII deficiency, a 5M urea clot solubility test was used. Plasma FXIII A‐ and B‐subunit antigen levels were determined by ELISA. FXIII activity was measured with an incorporation assay. Sequencing of all exons and intron/exon boundaries of F13A was performed, and a novel splice site defect was confirmed by RT‐PCR analysis. Genetic analysis revealed six different mutations in the F13A gene. Two splice site mutations were detected, a novel c.1460+1G>A mutation in the first nucleotide of intron 11 and a previously reported c.2045G>A mutation in the last nucleotide of exon 14. Neither of them was expressed at protein level. A novel nonsense mutation in exon 4, c.567T>A, p.Cys188X, was identified, leading in homozygous form to severe FXIII deficiency. Two novel missense mutations were found in exons 8 and 9, c.1040C>A, p.Ala346Asp and c.1126T>C, p.Trp375Arg, and a previously reported missense mutation in exon 10, c.1241C>T, p.Ser413Leu. All patients homozygous for these missense mutations presented with severe FXIII deficiency. We have analysed a cohort of 27 individuals and reported four novel mutations leading to congenital FXIII deficiency.
Inflammation in neurodegenerative diseases – an update
Authors: Amor Sandra , Peferoen Laura A. N. , Vogel Daphne Y. S. , Breur Marjolein , van der Valk Paul , Baker David , van Noort Johannes M. 
Published: December 2013

SummaryNeurodegeneration, the progressive dysfunction and loss of neurons in the central nervous system (CNS), is the major cause of cognitive and motor dysfunction. While neuronal degeneration is well‐known inAlzheimer's andParkinson's diseases, it is also observed in neurotrophic infections, traumatic brain and spinal cord injury, stroke, neoplastic disorders, prion diseases, multiple sclerosis and amyotrophic lateral sclerosis, as well as neuropsychiatric disorders and genetic disorders. A common link between these diseases is chronic activation of innate immune responses including those mediated by microglia, the residentCNSmacrophages. Such activation can trigger neurotoxic pathways leading to progressive degeneration. Yet, microglia are also crucial for controlling inflammatory processes, and repair and regeneration. The adaptive immune response is implicated in neurodegenerative diseases contributing to tissue damage, but also plays important roles in resolving inflammation and mediating neuroprotection and repair. The growing awareness that the immune system is inextricably involved in mediating damage as well as regeneration and repair in neurodegenerative disorders, has prompted novel approaches to modulate the immune system, although it remains whether these approaches can be used in humans. Additional factors in humans include ageing and exposure to environmental factors such as systemic infections that provide additional clues that may be human specific and therefore difficult to translate from animal models. Nevertheless, a better understanding of how immune responses are involved in neuronal damage and regeneration, as reviewed here, will be essential to develop effective therapies to improve quality of life, and mitigate the personal, economic and social impact of these diseases.