bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased tree densities in South African savannas: >50 years of data suggests CO2 as a driver
Authors: Buitenwerf R. , Bond W. J. , Stevens N. , Trollope W. S. W. 
Published: September 2011

AbstractFor the past century, woody plants have increased in grasslands and savannas worldwide. Woody encroachment may significantly alter ecosystem functioning including fire regimes, herbivore carrying capacity, biodiversity and carbon storage capacity. Traditionally, increases in woody cover and density have been ascribed to changes in the disturbance regime (fire and herbivores) or rainfall. Increased atmospheric CO2 concentrations may also contribute, by increasing growth rates of trees relative to grasses. This hypothesis is still heavily debated because usually potential CO2 effects are confounded by changes in land use (disturbance regime). Here we analyse changes in woody density in fire experiments at three sites in South African savannas where the disturbance regime (fire and herbivores) was kept constant for 30 and 50 years. If global drivers had significant effects on woody plants, we would expect significant increases in tree densities and biomass over time under the constant disturbance regime. Woody density remained constant in a semiarid savanna but tripled in a mesic savanna between the 1970s and 1990s. At the third site, a semiarid savanna near the southern limits of the biome, tree density doubled from the mid 1990s to 2010. Interpretation of the causes is confounded by population recovery after clearing, but aerial photograph analysis on adjacent non‐cleared areas showed an accompanying 48% increase in woody cover. Increased CO2 concentrations are consistent with increased woody density while other global drivers (rainfall) remained constant over the duration of the experiments. The absence of a response in one semiarid savanna could be explained by a smaller carbon sink capacity of the dominant species, which would therefore benefit less from increased CO2. Understanding how savannas and grasslands respond to increased CO2 and identifying the causes of woody encroachment are essential for the successful management of these systems.
Terrestrial biosphere models need better representation of vegetation phenology: results from the North American Carbon Program Site Synthesis
Authors: Richardson Andrew D. , Anderson Ryan S. , Arain M. Altaf , Barr Alan G. , Bohrer Gil , Chen Guangsheng , Chen Jing M. , Ciais Philippe , Davis Kenneth J. , Desai Ankur R. , Dietze Michael C. , Dragoni Danilo , Garrity Steven R. , Gough Christopher M. , Grant Robert , Hollinger David Y. , Margolis Hank A. , McCaughey Harry , Migliavacca Mirco , Monson Russell K. , Munger J. William , Poulter Benjamin , Raczka Brett M. , Ricciuto Daniel M. , Sahoo Alok K. , Schaefer Kevin , Tian Hanqin , Vargas Rodrigo , Verbeeck Hans , Xiao Jingfeng , Xue Yongkang 
Published: September 2011

AbstractPhenology, by controlling the seasonal activity of vegetation on the land surface, plays a fundamental role in regulating photosynthesis and other ecosystem processes, as well as competitive interactions and feedbacks to the climate system. We conducted an analysis to evaluate the representation of phenology, and the associated seasonality of ecosystem‐scale CO2 exchange, in 14 models participating in the North American Carbon Program Site Synthesis. Model predictions were evaluated using long‐term measurements (emphasizing the period 2000–2006) from 10 forested sites within the AmeriFlux and Fluxnet‐Canada networks. In deciduous forests, almost all models consistently predicted that the growing season started earlier, and ended later, than was actually observed; biases of 2 weeks or more were typical. For these sites, most models were also unable to explain more than a small fraction of the observed interannual variability in phenological transition dates. Finally, for deciduous forests, misrepresentation of the seasonal cycle resulted in over‐prediction of gross ecosystem photosynthesis by +160 ± 145 g C m−2 yr−1 during the spring transition period and +75 ± 130 g C m−2 yr−1 during the autumn transition period (13% and 8% annual productivity, respectively) compensating for the tendency of most models to under‐predict the magnitude of peak summertime photosynthetic rates. Models did a better job of predicting the seasonality of CO2 exchange for evergreen forests. These results highlight the need for improved understanding of the environmental controls on vegetation phenology and incorporation of this knowledge into better phenological models. Existing models are unlikely to predict future responses of phenology to climate change accurately and therefore will misrepresent the seasonality and interannual variability of key biosphere–atmosphere feedbacks and interactions in coupled global climate models.
Willows indirectly reduce arbuscular mycorrhizal fungal colonization in understorey communities
Authors: Becklin Katie M. , Pallo Megan L. , Galen Candace 
Published: September 2011

Summary1. Understanding mechanisms underlying species distributions is a central theme in ecology. This study identifies factors driving spatial variation in arbuscular mycorrhizal fungi (AMF). We conducted two experiments to test whether heterogeneity in AMF colonization of alpine perennial plants across a willow‐meadow ecotone is due to variation in (i) above‐ground competition with willows for light (experiment 1), (ii) below‐ground interactions with willows and their ectomycorrhizal fungi (EMF; experiment 1) or (iii) leaf litter deposition (experiment 2).2. In experiment 1, we tested the above‐ground interactions hypothesis by covering open meadow plots with 80% shade cloth to simulate willow shading (S). To test the below‐ground interactions hypothesis, we transplanted ectomycorrhizal (MW) and nonmycorrhizal willows (NW) into the open meadow. AMF colonization of herbaceous plants in the S, MW and NW treatments was compared to colonization of plants growing in unmanipulated open meadow (OC) and willow understorey (WC) control plots. In experiment 2, we tested the leaf litter hypothesis by manipulating leaf litter deposition in open meadow and willow understorey plots. AMF and EMF colonization was compared in plots with and without leaf litter.3. In experiment 1, AMF colonization was reduced in MW and WC plots compared to the other three treatments, suggesting that below‐ground interactions with EMF suppressed AMF colonization of herbaceous hosts. In experiment 2, the presence of leaf litter increased EMF colonization in the open meadow and reduced AMF colonization in both open meadow and willow understorey habitats, suggesting that willow‐derived leaf litter indirectly affected AMF colonization by promoting EMF colonization.4. Synthesis. Our results indicate that willows indirectly reduce AMF colonization of neighbouring herbaceous plants via feedbacks with leaf litter and EMF. These willow‐mediated effects could alter the distribution of mycorrhizal fungi in alpine communities, which could in turn impact the fitness and distribution of closely associated host species. Ultimately, this study demonstrates the potential for below‐ground interactions to drive variation in species associations across ecotonal boundaries.
Cyclic vomiting syndrome and functional vomiting in adults: association with cannabinoid use in males
Authors: Choung R. S. , Locke G. R. , Lee R. M. , Schleck C. D. , Zinsmeister A. R. , Talley N. J. 
Published: September 2011

AbstractBackground Cyclic vomiting syndrome (CVS) is characterized by stereotypical episodes of vomiting separated by symptom‐free intervals. However, the difficulty encountered in the management of patients with CVS may be a reflection of a deficiency in our understanding of the disorder. We aimed to evaluate whether clinical or gastric emptying (GE) data discriminate patients labeled as having CVS from functional vomiting (FV) or irritable bowel syndrome (IBS).Methods The medical records of patients diagnosed with any vomiting (including CVS, FV) over a 13‐year period (1993–2006) at our institution were carefully reviewed. Disease controls were age and gender matched subjects with IBS. Gastric emptying was performed by scintigraphy (99mTc‐egg meal). The associations of clinical factors and GE data with patient status (CVSvsFV or IBS) were analyzed.Key Results A total of 82 patients with CVS and 62 FV patients were identified. Younger age [per 10 years, OR = 0.7 (0.5, 0.9)], male gender [OR = 0.4 (0.2, 0.9)], and cannabinoid use [OR = 2.9 (1.2, 7.2)] were significantly associated with CVS compared with FV. However, there were no significant associations between patient status (CVSvsFV) and age, BMI, smoking, alcohol use, gastrointestinal symptoms, or GE. The proportion of cannabinoid users was significantly higher in patients with CVS compared with patients with IBS, whereas proportions for headaches and psychiatric disease were higher in subjects with IBS.Conclusions & Inferences Cyclic vomiting syndrome (vsFV) was not associated with clinical factors, but was associated with younger age, male gender and cannabinoid use. A larger proportion of CVS (vsIBS) patients had used cannabinoids.
FluoroSpot Analysis of TLR‐Activated Monocytes Reveals Several Distinct Cytokine‐Secreting Subpopulations
Authors: Smedman C. , Ernemar T. , Gudmundsdotter L. , Gille‐Johnson P. , Somell A. , Nihlmark K. , Gårdlund B. , Andersson J. , Paulie S. 
Published: September 2011

AbstractMonocytes have long been considered a heterogeneous group of cells both in terms of morphology and function. In humans, three distinct subsets have been described based on their differential expression of the cell surface markers CD14 and CD16. However, the relationship between these subsets and the production of cytokines has for the most part been based on ELISA measurements, making it difficult to draw conclusions as to their functional profile on the cellular level. In this study, we have investigated lipoteichoic acid (LTA)‐ and lipopolysaccharide (LPS)‐induced cytokine secretion by monocytes using the FluoroSpot technique. This method measures the number of cytokine‐secreting cells on the single‐cell level and uses fluorescent detection, allowing for the simultaneous analysis of two cytokines from the same population of isolated cells. By this approach, human monocytes from healthy volunteers could be divided into several subgroups as IL‐1β, IL‐6, TNF‐α and MIP‐1β were secreted by larger populations of responding cells (25.9–39.2%) compared with the smaller populations of GM‐CSF (9.1%), IL‐10 (1.3%) and IL‐12p40 (1.2%). Furthermore, when studying co‐secretion in FluoroSpot, an intricate relationship between the monocytes secreting IL‐1β and/or IL‐6 and those secreting TNF‐α, MIP‐1β, GM‐CSF, IL‐10 and IL‐12p40 was revealed. In this way, dissecting the secretion pattern of the monocytes in response to TLR‐2 or TLR‐4 stimulation, several subpopulations with distinct cytokine‐secreting profiles could be identified.
Seismic evidence of up to 200 m lake‐level change in Southern Patagonia since Marine Isotope Stage 4
Authors: GEBHARDT ANDREA CATALINA , OHLENDORF CHRISTIAN , NIESSEN FRANK , DE BATIST MARC , ANSELMETTI FLAVIO S. , ARIZTEGUI DANIEL , KLIEM PIERRE , WASTEGÅRD STEFAN , ZOLITSCHKA BERND 
Published: September 2011

AbstractMaar lake Laguna Potrok Aike is located north of the Strait of Magellan (south‐eastern Patagonia). Seismic reflection profiles revealed a highly dynamic palaeoclimate history. Dunes were identified in the eastern part of the lake at approximately 30 to 80 m below the lake floor, overlying older lacustrine strata, and suggest that the region experienced dry conditions probably combined with strong westerly winds. It is quite likely that this can be linked to a major dust event recorded in the Antarctic ice cores during Marine Isotope Stage 4. The dunes are overlain by a series of palaeo‐shorelines indicating a stepwise water‐level evolution of a new lake established after this dry period, and thus a change towards wetter conditions. After the initial, rapid and stepwise lake‐level rise, the basin became deeper and wider, and sediments deposited on the lake shoulder at approximately 33 m below present‐day lake level point towards a long period of lake‐level highstand between roughly 53·5 ka cal. bp and 30 ka cal. bp with a maximum lake level some 200 m higher than the desiccation horizon. This highstand was then followed by a regressional phase of uncertain age, although it must have happened some time between approximately 30 ka cal. bp and 6750 yrs cal. bp. Dryer conditions during the Mid‐Holocene are evidenced by a dropping lake level, resulting in a basin‐wide erosional unconformity on the lake shoulder. A second stepwise transgression between ca 5·8 to 5·4 ka cal. bp and ca 4·7 to 4 ka cal. bp with palaeo‐shorelines deposited on the lake shoulder unconformity again indicates a change towards wetter conditions.
Rock pool tufa stromatolites on a modern South African wave‐cut platform: partial analogues for Archaean stromatolites?
Authors: Smith Alan M. , Andrews Julian E. , Uken Ronald , Thackeray Zane , Perissinotto Renzo , Leuci Rio , Marca‐Bell Alina 
Published: September 2011

Terra Nova, 23, 375–381, 2011AbstractCalcifying tufa stromatolites are forming on a high energy coast of the South African Indian Ocean. The tufa stromatolites form in upper intertidal to supra tidal rock pools, encrust bedrock and are linked both laterally and vertically to physico‐chemical properties of their pool water. Calcification only occurs in pools where dissolved carbonate‐rich, spring‐fed groundwater is routed, and δ18O values are consistent with calcification in a mixture of freshwater and seawater. Increasing pH and less negative isotope values away from the spring are consistent with CO2 degassing and in‐stream calcification, albeit with some in‐mixing of seawater. The rocky shore setting of these active tufa stromatolites is new and invites serious comparison with some Archaean rocky substrate peritidal stromatolites (e.g. the c. 3.45 Ga Strelley Pool sequences, Pilbara Craton). This new association shows that initial encrustation of rocky intertidal substrates can begin with freshwater influence in the intertidal zone, a facies detail that should be sought in ancient peritidal stromatolites.
Plastid stromules are induced by stress treatments acting through abscisic acid
Authors: Gray John C. , Hansen Michael R. , Shaw Daniel J. , Graham Katie , Dale Rosemary , Smallman Philippa , Natesan Senthil K.A. , Newell Christine A. 
Published: September 2011

SummaryStromules are highly dynamic stroma‐filled tubules that extend from the surface of all plastid types in all multi‐cellular plants examined to date. The stromule frequency (percentage of plastids with stromules) has generally been regarded as characteristic of the cell and tissue type. However, the present study shows that various stress treatments, including drought and salt stress, are able to induce stromule formation in the epidermal cells of tobacco hypocotyls and the root hairs of wheat seedlings. Application of abscisic acid (ABA) to tobacco and wheat seedlings induced stromule formation very effectively, and application of abamine, a specific inhibitor of ABA synthesis, prevented stromule induction by mannitol. Stromule induction by ABA was dependent on cytosolic protein synthesis, but not plastid protein synthesis. Stromules were more abundant in dark‐grown seedlings than in light‐grown seedlings, and the stromule frequency was increased by transfer of light‐grown seedlings to the dark and decreased by illumination of dark‐grown seedlings. Stromule formation was sensitive to red and far‐red light, but not to blue light. Stromules were induced by treatment with ACC (1‐aminocyclopropane‐1‐carboxylic acid), the first committed ethylene precursor, and by treatment with methyl jasmonate, but disappeared upon treatment of seedlings with salicylate. These observations indicate that abiotic, and most probably biotic, stresses are able to induce the formation of stromules in tobacco and wheat seedlings.
Favorable outcome in a renal transplant recipient with donor‐derived infection due to multidrug‐resistant Pseudomonas aeruginosa
Authors: Simkins J. , Muggia V. 
Published: September 2011

Abstract:Most cases of donor‐derived infection due to Pseudomonas aeruginosa reported in the literature are associated with vascular dehiscence, all of which resulted either in death or graft failure requiring graft removal. We report the successful treatment of donor‐derived infection due to multidrug‐resistant P. aeruginosa in a 64‐year‐old male who presented with bacteremia and peritransplant renal fluid collection after undergoing deceased‐donor renal transplantation.As a result of the report of positive donor cultures by the host Organ Procurement Organization, the infection was promptly identified by blood cultures drawn before appearance of symptoms. Surveillance blood cultures in recipients are not usually recommended. However, they should be done if donor cultures turn positive. Therefore, it is crucial to perform cultures in donors and to closely follow them up for early identification and prompt treatment of donor‐transmitted infections due to organisms like P. aeruginosa that can be graft and/or life threatening.
Beckwith–Wiedemann syndrome with placental chorangioma due to H19‐differentially methylated region hypermethylation: A case report
Authors: Aoki Aiko , Shiozaki Arihiro , Sameshima Azusa , Higashimoto Ken , Soejima Hidenobu , Saito Shigeru 
Published: September 2011

AbstractBeckwith–Wiedemann syndrome (BWS) is a common overgrowth syndrome that involves abdominal wall defects, macroglossia, and gigantism. It is sometimes complicated by placental tumor and polyhydramnios. We report a case of BWS, prenatally diagnosed with ultrasonography. A large and well‐circumscribed tumor also existed on the fetal surface of the placenta, which was histologically diagnosed as chorangioma after delivery. Polyhydramnios was obvious and the fetal heart enlarged progressively during pregnancy. Because the biophysical profiling score dropped to 4 points at 33 weeks of gestation, we carried out cesarean section. By epigenetic analysis, H19‐differentially methylated region hypermethylation was observed in the placental tumor, normal placental tissue, and cord blood mononuclear cells. This is the first report of BWS with placental tumor due to H19‐differentially methylated region hypermethylation.
Gestation‐specific reference intervals for right and left ventricular ejection force from 12 to 40 weeks of gestation
Authors: Parasuraman Rajeswari , Osmond Clive , Howe David T. 
Published: September 2011

AbstractAim:  Ejection force of the fetal cardiac ventricles has previously been described from 18 weeks of gestation. We aimed to establish gestation‐specific reference intervals for ventricular ejection force (VEF) from 12 to 40 weeks of pregnancy.Material and Methods:  In a cross‐sectional observational study of singleton pregnancies, examinations were performed in 236 women evenly distributed across each week of pregnancy from 12 to 40 weeks. Each mother was scanned once. For the aortic and pulmonary valves, the time to peak velocity (TPV) and the average (TAV) and peak flow velocity in systole (PSV) was measured. For each we averaged values from three consecutive complexes. The outlet valve diameters were measured and the VEF on both the right and left sides were calculated using the formula VEF = (1.055 × valve area × time to peak velocity × TAV) × (PSV/TPV) where 1.055 represents the density of blood. Measurements were repeated in 40 women to assess intraobserver reproducibility and in 19 women for interobserver variability.Results:  We present reference intervals for right and left VEF. We demonstrated that the ventricular force on both right and left sides increases with advancing gestational age.Conclusion:  Fetal cardiac physiology can be studied and Doppler indices reliably measured as early as the late first trimester of pregnancy. Ventricular ejection force and its relationship with fetal growth could be explored in future studies and this may eventually provide better understanding of changes which may predispose to adult cardiac disease.
Reduction in maternal complement levels during delivery by cesarean section
Authors: Kato Makoto , Itoh Hiroaki , Nagahashi Kotomi , Izima Mari , Yaguchi Chizuko , Uchida Toshiyuki , Suzuki Kazunao , Sugihara Kazuhiro , Kanayama Naohiro 
Published: September 2011

AbstractAim:  Primary elective cesarean sections are being carried out in considerable numbers in both developed and developing countries; however, little information is available concerning differences in maternal physiological responses associated with the mode of delivery. The aim of the present study was to compare the changes in the maternal complement and contact systems between delivery by cesarean section and vaginal delivery at term.Methods:  Maternal levels of complement 3 (C3), complement 4 (C4) and coagulation factor XII (FXII) were measured during primary elective cesarean (n = 70) and vaginal (n = 140) deliveries.Results:  The C3, C4 and FXII levels decreased significantly during delivery by cesarean section and remained low for two hours. By contrast, C3 levels, but not C4 levels, increased temporally during normal term delivery and FXII levels decreased two hours later.Conclusions:  The changes in maternal C3, C4 and FXII levels during cesarean section were very different from those during delivery at term, suggesting that the maternal complement and contact systems respond differently.
Quality assurance and improvement: the Pediatric Regional Anesthesia Network
Authors: Polaner David M. , Martin Lynn D. ,   the PRAN Investigators
Published: September 2011

SummaryQuality assurance and improvement (QA/QI) is a critical activity in medicine. The use of large‐scale collaborative databases is increasingly essential to obtain enough reports with which to establish standards of practice and define the incidence of complications and risk/benefit ratios for rare events. Such projects can enhance local QA/QI endeavors by enabling institutions to obtain benchmark data against which to compare their performance and can be used for prospective analyses of inter‐institutional differences to determine ‘best practice’. The pediatric regional anesthesia network (PRAN) is such a project. The first data cohort is currently being analyzed and offers insight into how such data can be used to detect trends in adverse events and improve care.