Aphids decelerate litter nitrogen mineralisation through changes in litter quality

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Development and characterization of 11 microsatellite markers in the rock sparrow,Petronia petronia

Eleven polymorphic microsatellite loci were isolated in the passeriform Petronia petronia using the enrichment protocol FIASCO (fast isolation by AFLP of sequences containing repeats). We detected three to 13 alleles per locus in 25 specimens collected from an Italian population. The level of expected heterozygosity ranged from 0.439 to 0.856. One locus is sex linked to the Z chromosome. The total exclusionary probabilities using these loci for the first and the second parent were 0.978 and 0.999, respectively. These are the first microsatellite loci characterized from the rock sparrow that can be used for estimating population structure and for large‐scale parentage analysis.     

Semiempirical modeling of abiotic and biotic factors controlling ecosystem respiration across eddy covariance sites

In this study we examined ecosystem respiration (R_ECO) data from 104 sites belonging to FLUXNET, the global network of eddy covariance flux measurements. The goal was to identify the main factors involved in the variability of R_ECO: temporally and between sites as affected by climate, vegetation structure and plant functional type (PFT) (evergreen needleleaf, grasslands, etc.). We demonstrated that a model using only climate drivers as predictors of R_ECO failed to describe part of the temporal variability in the data and that the dependency on gross primary production (GPP) needed to be included as an additional driver of R_ECO. The maximum seasonal leaf area index (LAI_MAX) had an additional effect that explained the spatial variability of reference respiration (the respiration at reference temperature T_ref=15 °C, without stimulation introduced by photosynthetic activity and without water limitations), with a statistically significant linear relationship (r²=0.52, P<0.001, n=104) even within each PFT. Besides LAI_MAX, we found that reference respiration may be explained partially by total soil carbon content (SoilC). For undisturbed temperate and boreal forests a negative control of total nitrogen deposition (N_depo) on reference respiration was also identified. We developed a new semiempirical model incorporating abiotic factors (climate), recent productivity (daily GPP), general site productivity and canopy structure (LAI_MAX) which performed well in predicting the spatio‐temporal variability of R_ECO, explaining >70% of the variance for most vegetation types. Exceptions include tropical and Mediterranean broadleaf forests and deciduous broadleaf forests. Part of the variability in respiration that could not be described by our model may be attributed to a series of factors, including phenology in deciduous broadleaf forests and management practices in grasslands and croplands.     

Cord blood–derived cytokine-induced killer cells combined with blinatumomab as a therapeutic strategy for CD19+ tumors

Background

Cytokine-induced killer cells (CIKs) are an advanced therapeutic medicinal product (ATMP) that has shown therapeutic activity in clinical trials but needs optimization. We developed a novel strategy using CIKs from banked cryopreserved cord blood units (CBUs) combined with bispecific antibody (BsAb) blinatumomab to treat CD19⁺ malignancies.

The species–area relationship in centipedes (Myriapoda: Chilopoda): a comparison between Mediterranean island groups

The present study article examines the shapes of centipede species–area relationships (SARs) in the Mediterranean islands, compares the results of the linear form of the power model between archipelagos, discusses biological significance of the power model parameters with other taxa on the Aegean archipelago, and tests for a significant small‐island effect (SIE). We used 11 models to test the SARs and we compared the quality‐of‐fit of all candidate models. The power function ranked first and Z‐values was in the range 0.106–0.334. We assessed the presence of SIEs by fitting both a continuous and discontinuous breakpoint regression model. The continuous breakpoint regression functions never performed much better than the closest discontinuous model as a predictor of centipede species richness. We suggest that the relatively low Z‐values in our data partly reflect better dispersal abilities in centipedes than in other soil invertebrate taxa. Longer periods of isolation and more recent island formation may explain the somewhat lower constant c in the western Mediterranean islands compared to the Aegean islands. Higher breakpoint values in the western Mediterranean may also be a result of larger distance to the mainland and longer separation times. Despite the differences in the geological history and the idiosyncratic features of the main island groups considered, the overall results are quite similar and this could be assigned to the ability of centipedes to disperse across isolation barriers. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 146–159.     

Analysis of segment number and enzyme variation in a centipede reveals a cryptic species, Geophilus easoni sp. nov., and raises questions about speciation

Geophilomorph centipedes provide an unusual opportunity to examine patterns of variation in segment number within extant species. (Most other arthropod species are invariant in this respect.) Recent work on several geophilomorph species has revealed latitudinal clines in segment number, but has generally not called into question the identities of the species themselves. However, analysis of a unique pattern of variation in British populations of Geophilus carpophagus Leach, coupled with other morphological and enzyme data, reveals a cryptic species, Geophilus easoni sp. nov. This species has not yet been detected on the European mainland. Four distinct hypotheses are advanced regarding the speciation event through which G. easoni arose and the phylogeographic processes that resulted in the present distributions of the two species in Britain. Further study will be necessary to test these hypotheses. In any event, G. carpophagus and G. easoni provide something that has until now been absent: a case study of the genetic differences between closely-related geophilomorph species.     

Reduced Soluble Proteins Associated with Maize Endosperm Protein Bodies

Endosperm protein bodies from developing maize were purifiedby discontinuous sucrose gradient centrifugation and the proteincontent analysed by sodium dodecyl sulphate polyacrylamide gelelectrophoresis (SDS-PAE). Major proteins detected were zeinpolypeptides plus a component with Mr 28 000 and a doublet aroundMr 58 000. These proteins were present only in the protein bodyfraction of the sucrose gradient. Treatment of protein bodieswith the reducing agent dithiothreitol (DTT) in aqueous bufferdissolved the components with Mr 28 000 and 58 000, plus minorones, but not zein. The reduced soluble proteins were separatedby DEAE-Sephacel chromatography into three fractions: two ofthese contained the component with Mr 28 000, and the thirdthe components around Mr 58 000 plus minor ones. Proteins fromthe three fractions had characteristic amino acid compositions,markedly different from those of zein polypeptides. Chymotrypticdigestion experiments performed on protein bodies under variousconditions, and two-dimensional electrophoresis of proteinsfrom protein bodies suggested that the major zein polypeptides,the protein with Mr 28 000 and the other reduced soluble proteinshave different native organizations.     

Mating Types in Aspidisca sp. (Ciliophora, Hypotrichida): a Cluster of Cryptic Species

A mating-type analysis was performed on 78 stocks of the marine hypotrich ciliate, Aspidisca sp., from a sufficient number of diverse geographic locations, some widely separated. Evidence is provided for the existence of a binary mating system in this "morphospecies." The collected stocks have been challenged by the most rigorous criterion, namely breeding affinity in the laboratory, and have yielded at least four reproductively, not necessarily geographically, isolated groups that are in fact "biological species," here referred to as "syngens." Different syngens contain different pairs of mating types. Syngens are morphologically indistinguishable; hence Aspidisca sp. can be considered a conservative taxon comprising a number of "cryptic" or "sibling species." Information is also presented about the mating behavior and the pattern of nuclear events at conjugation in Aspidisca sp. Search for soluble pheromones of the mating types gave only negative results. Hence, direct contact with potential partners is postulated to play a critical role in preparing individuals to mate. Mating reaction and mating which actually involves cross-fertilization (conjugation, sensu stricto) are completely inhibited by 10 μg/ml cycloheximide, suggesting the necessity of protein synthesis for recognition and union in conjugation of potential partners.