bluuebunny/crossref_metadata_2025_split huggingface dataset:
NMRstructure of bitistatin – a missing piece in the evolutionary pathway of snake venom disintegrins
Authors: Carbajo Rodrigo J. , Sanz Libia , Perez Alicia , Calvete Juan J. 
Published: November 2014

Extant disintegrins, as found in the venoms ofViperidaeandCrotalidaesnakes (vipers and rattlesnakes, represent a family of polypeptides that block the function of β1 and β3 integrin receptors, both potently and with a high degree of selectivity. This toxin family owes its origin to the neofunctionalization of the extracellular region of anADAM(a disintegrin and metalloprotease) molecule recruited into the snake venom gland proteome in the Jurassic. The evolutionary structural diversification of the disintegrin scaffold, from the ancestral long disintegrins to the more recently evolved medium‐sized, dimeric and short disintegrins, involved the stepwise loss of pairs of class‐specific disulfide linkages and the processing of the N‐terminal region.NMRand crystal structures of medium‐sized, dimeric and short disintegrins have been solved. However, the structure of a long disintegrin remained unknown. The present study reports theNMRsolution structures of two disulfide bond conformers of the long disintegrin bitistatin from the African puff adderBitis arietans. The findings provide insight into how a structural domain of the extracellular region of anADAMmolecule, recruited into and selectively expressed in the snake venom gland proteome as aPIIImetalloprotease in the Jurassic, has subsequently been tranformed into a family of integrin receptor antagonists.
Are there links between responses of soil microbes and ecosystem functioning to elevated CO2, N deposition and warming? A global perspective
Authors: García‐Palacios Pablo , Vandegehuchte Martijn L. , Shaw E. Ashley , Dam Marie , Post Keith H. , Ramirez Kelly S. , Sylvain Zachary A. , de Tomasel Cecilia Milano , Wall Diana H. 
Published: November 2014

AbstractIn recent years, there has been an increase in research to understand how global changes’ impacts on soil biota translate into altered ecosystem functioning. However, results vary between global change effects, soil taxa, and ecosystem processes studied, and a synthesis of relationships is lacking. Therefore, here we initiate such a synthesis to assess whether the effect size of global change drivers (elevated CO2, N deposition, and warming) on soil microbial abundance is related with the effect size of these drivers on ecosystem functioning (plant biomass, soil C cycle, and soil N cycle) using meta‐analysis and structural equation modeling. For N deposition and warming, the global change effect size on soil microbes was positively associated with the global change effect size on ecosystem functioning, and these relationships were consistent across taxa and ecosystem processes. However, for elevated CO2, such links were more taxon and ecosystem process specific. For example, fungal abundance responses to elevated CO2 were positively correlated with those of plant biomass but negatively with those of the N cycle. Our results go beyond previous assessments of the sensitivity of soil microbes and ecosystem processes to global change, and demonstrate the existence of general links between the responses of soil microbial abundance and ecosystem functioning. Further we identify critical areas for future research, specifically altered precipitation, soil fauna, soil community composition, and litter decomposition, that are need to better quantify the ecosystem consequences of global change impacts on soil biodiversity.
Sustained virological response to antiviral therapy improves survival rate in patients with recurrent hepatitis C virus infection after liver transplantation
Authors: Kawaoka Tomokazu , Takahashi Shoichi , Kawakami Yoshiiku , Tsuge Masataka , Hiramatsu Akira , Imamura Michio , Hyogo Hideyuki , Aikata Hiroshi , Ishiyama Kohei , Tashiro Hirotaka , Ohdan Hideki , Tanaka Junko , Chayama Kazuaki 
Published: November 2014

AimPrevious European and North American studies analyzed the relationship between survival rate and sustained virological response (SVR) to interferon (IFN) therapy in patients with recurrent hepatitis C viral (HCV) infection after liver transplantation (LT). The present study was designed to define the same relationship in Japanese patients who had undergone LT.MethodsForty‐seven patients (genotype 1, 40; genotype 2, 7) with recurrent HCV after LT were treated with pegylated interferon (PEG IFN) or IFN/ribavirin (RBV). In possible, within 3 months after LT, patients started treatment with PEG IFN‐α‐2b or IFN‐α‐2b s.c. once weekly combined with RBV (200 mg/day).ResultsThe SVR rate was 51% (24/47) for all patients, 42.5% (17/40) for genotype 1 and 100% (7/7) for genotype 2. The median follow‐up period was 71 months (range, 24–152). The survival rate of 24 patients who achieved SVR was 95% at 5 years and 92% at 10 years. These rates were significantly better than those of 23 patients who did not achieve SVR (82% at 5 years, 58% at 10 years) (P = 0.027). Two patients of the SVR group died during follow up (due to hepatocellular carcinoma in one and chronic rejection in one), while six non‐SVR patients died during the same period (three died due to liver failure by recurrent HCV).ConclusionSVR following IFN therapy contributes to improvement of survival rate in patients with recurrent post‐LT HCV infection.
Phase equilibria constraints on the melt fertility of crustal rocks: the effect of subsolidus water loss
Authors: Webb G. , Powell R. , McLaren S. 
Published: November 2014

AbstractDuring regional prograde metamorphism, H2O generated by ongoing dehydration reactions is likely to be continuously lost from a rock by compaction. Classical melting experiments cannot easily simulate this phenomenon, because ideally, all run products are conserved within the experimental charge, although significant equilibration and H2O generation may occur during heating. Phase equilibria modelling is used to consider the effect of subsolidus water loss (SWL) on subsequent melting relationships of felsic lithologies (including metapelite, metagreywacke and metatonalite) in the suprasolidus. SWL drives the bulk composition towards the minimum saturation point on the boundary of the wet‐melting field and results in significantly reduced subsequent melt generation when compared to melting experiments involving conservation of subsolidus H2O. This effect is most significant at P–T conditions just above the solidus. For initially hydrated rocks, the reduction in melt production causes rheologically critical thresholds (e.g. melt connectivity threshold, melt escape threshold and the solid‐to‐liquid transition) to be intersected at temperatures generally more than 100 °C, higher than predicted by idealized experimental melting curves.
Alternative fire‐driven vegetation states
Authors: Pausas Juli G. 
Published: November 2014

AbstractThere is increasing evidence that alternative stable vegetation types exist for a given climate that are maintained by distinct fire regimes. Paritsis et al. (2014, this issue) provide an example in a temperate ecosystem. Here I briefly review cases of bi‐stability in various climates, and present a simple model for the transition between states in their system.
Stochastic processes and crop types shape weed community assembly in arable fields
Authors: Perronne Rémi , Le Corre Valérie , Bretagnolle Vincent , Gaba Sabrina 
Published: November 2014

AbstractAimsIn agro‐ecosystems, crop types, i.e., the crop species and its associated agricultural practices, have been shown to influence the taxonomic as well as functional composition of weed communities. However, the processes underlying weed community assembly within a crop type are poorly understood, especially regarding the contributions of local factors and stochastic processes. In this study, we investigate the effects of the crop type in shaping local weed communities.LocationLTER Zone Atelier Plaine et Val de Sèvre, an intensive cereal system in western France.MethodsWe selected 105 fields of five crop types and investigated the functional structure of weed communities for those traits that define the Leaf–Height–Seed (L‐H‐S) strategy as well as phenological traits. We compared the observed trait distribution to trait distributions expected under random assembly. The trait distributions were described by the range, the community‐weighted mean and the dispersion of each trait, and simulated communities were generated with a null model approach that randomizes the ‘species × traits’ matrix to maintain equiprobable the occurrence of each trait combination. The relationship between trait values and species abundance within each community was investigated using Kendall rank correlation tests.ResultsOur results showed that, in ca. 90% of the fields, the functional diversity of weed communities did not differ from what would be expected under random assembly. Departures from random expectations essentially resulted from shifts in weighted mean values for phenological traits. Weed communities of sunflower, maize and spring pea had later onsets of emergence and flowering than randomly expected. Communities of winter wheat had smaller species and earlier onset of flowering, and communities from oilseed rape had a larger duration of the emergence period and earlier onset of flowering. In addition, we found a positive significant relationship between species abundance and trait values for phenology for spring pea, sunflower and maize, suggesting that species with a later onset of emergence and flowering period have higher performance in these weed communities.ConclusionsAt landscape scale, weed communities generally showed patterns of functional diversity in accordance with those expected under random community assembly, except for phenological traits in spring and summer crops, where patterns were rather consistent with environmental filtering.
Intraspecific trait variability matters
Authors: Albert Cecile H. 
Published: November 2014

AbstractIntraspecific trait variability (ITV) plays a central part in various ecological processes, though using mean trait values may be sufficient in some instances. Ecologists need thus to find under which circumstances. Carlucci et al. (2014, this issue) bring new evidence on the importance of ITV for community assembly across a strong gradient. Sampling design may affect ITV quantification across gradients.
Fatigue in primary sclerosing cholangitis is associated with sympathetic over‐activity and increased cardiac output
Authors: Dyson Jessica K. , Elsharkawy Ahmed M. , Lamb Christopher A. , Al‐Rifai Ahmad , Newton Julia L. , Jones David E. , Hudson Mark 
Published: November 2014

AbstractBackground & AimsPatients with primary sclerosing cholangitis (PSC) frequently highlight the impact of fatigue on their life quality. The study aims were to evaluate fatigue and its associations in PSC and investigate whether overt autonomic dysfunction contributes to the expression of fatigue.MethodsAll PSC patients under active follow‐up at a regional liver centre were sent disease‐ and symptom‐assessment tools. Three control groups were utilized; unselected community controls, patients with inflammatory bowel disease (IBD) without PSC, and cholestatic controls with primary biliary cirrhosis (PBC). A representative subgroup of PSC patients and normal controls underwent formal autonomic assessment.ResultsSymptom‐assessment tools were returned by 40 non‐transplanted patients. PSC patients had significantly worse fatigue than population controls (P = 0.005). Fatigue was significant compared to population controls whether or not patients had accompanying IBD, although was more marked in those with both PSC and IBD. In patients with PSC and IBD, fatigue severity and autonomic symptoms were significantly increased in those with prior significant surgical intervention. Clinically significant autonomic dysfunction was seen in 22.5% of PSC patients, and of those, 78% had significant fatigue. Neurally mediated hypotension was found in 60% of PSC patients compared to 8% in the control group. The PSC group had increased sympathetic activity and reduced parasympathetic activity.ConclusionFatigue is a significant problem in a minority of PSC patients and appears to be associated with autonomic dysfunction. Fatigued PSC patients should be screened for autonomic dysfunction and targeting such dysfunction represents a potential approach to treatment which warrants further exploration.
Effect of Selective Prostaglandin E2 EP2 Receptor Agonist CP‐533,536 on Voiding Efficiency in Rats with Midodrine‐Induced Functional Urethral Obstruction
Authors: KURIHARA Ryoko , IMAZUMI Katsunori , TAKAMATSU Hajime , ISHIZU Kenichiro , YOSHINO Taiji , MASUDA Noriyuki 
Published: November 2014

ObjectivesWe investigated the effect of the selective prostaglandin E2 EP2 receptor agonist CP‐533,536 on voiding efficiency in rats with midodrine‐induced functional urethral obstruction.MethodsThe effect of CP‐533,536 (0.03–0.3 mg/kg, intravenous [i.v.]) on urethral perfusion pressure (UPP) was investigated in anesthetized rats pre‐treated with midodrine (1 mg/kg, i.v.), which forms an active metabolite that acts as an α1‐adrenoceptor agonist. The effect of CP‐533,536 (0.03–0.3 mg/kg, i.v.) on cystometric parameters was also investigated in anesthetized rats. In addition, the effect of CP‐533,536 (0.03–0.3 mg/kg, i.v.) on residual urine volume (RV) and voiding efficiency (VE) was investigated in conscious rats treated with midodrine (1 mg/kg, i.v.).ResultsCP‐533,536 dose‐dependently decreased UPP elevated by midodrine in anesthetized rats. In contrast, CP‐533,536 did not affect maximum voiding pressure, intercontraction interval, or intravesical threshold pressure. In conscious rats, midodrine (1 mg/kg, i.v.) markedly increased RV and reduced VE. CP‐533,536 dose‐dependently ameliorated increases in RV and decreases in VE induced by midodrine.ConclusionsThese results suggest that a selective EP2 receptor agonist could ameliorate the elevation of RV and improve the reduction of VE in rats with functional urethral obstruction caused by stimulation of α1‐adrenoceptors. The mechanism of action might be not potentiation of bladder contraction but rather preferential relief of urethral constriction.
Transition from Charge‐Transfer to Largely Locally Excited Exciplexes, from Structureless to Vibrationally Structured Emissions
Authors: Young Ralph H. , Feinberg Adam M. , Dinnocenzo Joseph P. , Farid Samir 
Published: November 2014

AbstractExciplexes of 9,10‐dicyanoanthracene (DCA) with alkylbenzene donors in cyclohexane show structureless emission spectra, typical of exciplexes with predominantly charge‐transfer (CT) character, when the donor has a relatively low oxidation potential (Eox), e.g. hexamethylbenzene (HMB). With increasing Eox and stronger mixing with a locally excited (LE) state, vibrational structure begins to appear with 1,2,3,5‐tetramethylbenzene and becomes prominent with p‐xylene (p‐Xy). A simple theoretical model reproduces the spectra and the radiative rate constants, and it reveals several surprises: Even in this nonpolar solvent, the fractional CT character of a highly mixed exciplex varies widely in response to fluctuations in the microscopic environment. Environments that favor the LE (or CT) state contribute more to the blue (or red) side of the overall spectrum. It is known that sparsely substituted benzene radical cations, e.g., p‐Xy•+, are stabilized more in acetonitrile than the heavily substituted HMB•+. Remarkably, ion pairing with DCA•– in cyclohexane leads to even larger differences in the stabilization of these radical cations. The spectra of the low‐Eox donors are almost identical except for displacements that approximately equal the differences in Eox, even though the exciplexes have varying degrees of CT character. These similarities result from compensation among several nonobvious, but quantified factors.
Enantiostylous types of Cassiinae species (Fabaceae‐Caesalpinioideae)
Authors: Almeida N. M. , Cotarelli V. M. , Souza D. P. , Novo R. R. , Siqueira Filho J. A. , Oliveira P. E. , Castro C. C. 
Published: November 2014

AbstractSpecies of the subtribe Cassiinae present a wide diversity of floral types. Until recently it was considered that this diversity did not extend to their reproductive mechanisms. However, studies have recorded some variations in the enantiostylous pattern in this plant group. This study aims to investigate the morphological and functional variations of enantiostyly in species of the subtribe Cassiinae. Additionally, it proposes the recognition of enantiostylous types (ET) based on pollen deposition and capture mode. Morphological data were collected in fresh and fixed (alcohol 70%) buds and flowers, and also using photos and rehydrated material from herbarium sheets, for a total of 59 species. The parameters used to establish the ETs were pollination type, nature of pollen deposition on the pollinator body, deposition type, number of petals involved in pollen deposition, and pollen pathway. Morpho‐functional features allowed the recognition of seven enantiostylous types (Flexuosa, Cana, Macranthera, Martiana, Amiciella, Repens and Ramosa) that present several levels of complexity. The type Ramosa was the most common and the Cana type was the least common. The types Repens, Martiana and Flexuosa do not have reciprocal pollen deposition, thus species with these types may be considered atypical. The groups resulting from similarity analysis partially coincide with the clades proposed in phylogenetic studies of Cassiinae. The recognition of functional ETs is important for understanding the evolution of reproductive strategies of Cassiinae species, and indicates an interesting line of investigation of enantiostyly in other plant groups.
Genetic structure of Verticillium dahliae isolates infecting olive trees in Tunisia using AFLP, pathogenicity and PCR markers
Authors: Gharbi Y. , Triki M. A. , Trabelsi R. , Fendri I. , Daayf F. , Gdoura R. 
Published: November 2014

Since 2006, verticillium wilt of olive induced by Verticillium dahliae has caused considerable economic losses in olive orchards in Tunisia. The genetic structure of V. dahliae isolates collected from different olive growing regions was investigated using virulence tests, vegetative compatibility grouping (VCG) and amplified fragment length polymorphism (AFLP) analyses. In total, 42 isolates of V. dahliae from diseased olive trees were tested. Cluster analysis and principal coordinate analysis revealed that geographic origin was the main factor determining the genetic structure of V. dahliae populations and both methods indicated a genetic separation between the central and coastal isolates. Isolates were divided into two major groups: the AFLP‐I group included all isolates from Sidi Bouzid, Kairouan, Kasserine and Sfax (centre of the country) and the AFLP‐II group included isolates from Monastir, Zaghouane, Sousse, Mahdia (coastal region), and two isolates from Sfax. Analysis of the molecular variance (amova) indicated a significant level of genetic differentiation among (76%) and within (23%) the two populations. Analyses of both the defoliating (D) and non‐defoliating (ND) pathotypes and VCG markers indicated that most of the isolates belong to VCG 2A and 4B/ND pathotype. The disease severity was highly variable among the isolates tested (P < 0·05) with no evidence of association between aggressiveness and geographical origin of the isolates. Overall, results of this study revealed a clear association between the genetic diversity of the isolates and their geographic origin, but not between genetic diversity and virulence patterns.
Estimating the oxidative ratio of UK peats and agricultural soils
Authors: Clay G. D. , Worrall F. 
Published: November 2014

AbstractOrganic matter in the terrestrial biosphere has a fundamental role in moderating the exchange of CO2 between the atmosphere and the biosphere. One important property of organic matter is its oxidative ratio (OR); that is, the ratio of moles O2 released per mole CO2 sequestered through photosynthesis, that is, the lower the OR, less O2 is released per mole of CO2 fixed. In global assessments of CO2 partitioning, the failure to account for changes in OR could lead to an underestimate of terrestrial carbon sequestration. It is known that OR can vary between environments and management, but what other factors could be playing a role in controlling OR? This study measured the OR of a range of peat (Histosols) and mineral soils (Inceptisols) under similar management from across the United Kingdom to investigate how OR varies within and between material types. The study shows that OR values varied significantly between material types (median peat OR = 1.10, median vegetation OR = 1.03 and median mineral soil OR = 1.14), and they also varied between study sites. Furthermore, there were no significant differences in OR with peat depth. Given the results from this study, we can suggest that future sampling strategies should include sampling of the major carbon pools (i.e. vegetation, litter and soil) and that, as a first approximation, OR can be examined on the basis of these carbon pools alone. The values measured in the study give a new residence time‐weighted global OR estimate for the terrestrial biosphere () of 1.056 ± 0.02.
A classification of all 1-Salem graphs
Authors: Gumbrell Lee , McKee James 
Published: November 2014

AbstractOne way to study certain classes of polynomials is by considering examples that are attached to combinatorial objects. Any graph$G$has an associated reciprocal polynomial$R_{G}$, and with two particular classes of reciprocal polynomials in mind one can ask the questions: (a) when is$R_{G}$a product of cyclotomic polynomials (giving thecyclotomic graphs)? (b) when does$R_{G}$have the minimal polynomial of a Salem number as its only non-cyclotomic factor (the non-trivialSalem graphs)? Cyclotomic graphs were classified by Smith (Combinatorial structures and their applications, Proceedings of Calgary International Conference, Calgary, AB, 1969 (eds R. Guy, H. Hanani, H. Saver and J. Schönheim; Gordon and Breach, New York, 1970) 403–406); the maximal connected ones are known as Smith graphs. Salem graphs are ‘spectrally close’ to being cyclotomic, in that nearly all their eigenvalues are in the critical interval$[-2,2]$. On the other hand, Salem graphs do not need to be ‘combinatorially close’ to being cyclotomic: the largest cyclotomic induced subgraph might be comparatively tiny.We define an$m$-Salem graph to be a connected Salem graph$G$for which$m$is minimal such that there exists an induced cyclotomic subgraph of$G$that has$m$fewer vertices than$G$. The$1$-Salem subgraphs are both spectrally close and combinatorially close to being cyclotomic. Moreover, every Salem graph contains a$1$-Salem graph as an induced subgraph, so these$1$-Salem graphs provide some necessary substructure of all Salem graphs. The main result of this paper is a complete combinatorial description of all$1$-Salem graphs: in the non-bipartite case there are$25$infinite families and$383$sporadic examples.