Characterization of queen specific components of the fluid released by fighting honey bee queens

Swarming honey bee (Apis mellifera L.) colonies rear supernumerary young queens that compete for the limited resources (workers) necessary for founding a new colony. Young queens often fight to death. Queens show several adaptations to fight and conflict, such as short developmental time and early onset of venom production. During fights, queens often release rectal fluid with a strong smell of wine grapes, after which they temporarily stop fighting. This potentially reduces individual overall risk of deadly injury. The fluid and one of its components, ortho-aminoacetophenone, were previously found to have a pheromonal effect on workers, but the evidence is equivocal. Recently, it has been suggested that the effects of this substance may be context- or concentration-specific. We performed semi-quantitative gas-chromatography mass spectrometry (GC/MS) analysis of the fluid (1) released by queens during their first fight, (2) released during a subsequent fight, and (3) obtained by dissecting the hindgut of queens and (4) of workers. Following preliminary results by Page et al. 1988 (Experientia 44: 270-271), we scored presence / absence of eight substances. Five substances (ortho-aminoacetophenone, decanoic acid, dodecanoic acid, octyl decanoate, and decyl decanoate) were characteristic of queens only. ortho-Aminoacetophenone was detected in all queen and in none of the worker samples, in agreement with previous findings that worker faeces do not have any pheromonal effect. The fluid released by queens on their second fight also contained ortho-aminoacetophenone, but in smaller quantities. These data substantiate previous bioassay results, and provide estimates of ortho-aminoacetophenone concentration as required to design experiments addressing the function and adaptive significance of this behaviour

Carbon dioxide dissolution in structural and stratigraphic traps

The geologic sequestration of carbon dioxide (CO[subscript 2]) in structural and stratigraphic traps is a viable option to reduce anthropogenic emissions. While dissolution of the CO[subscript 2] stored in these traps reduces the long-term leakage risk, the dissolution process remains poorly understood in systems that reflect the appropriate subsurface geometry. Here, we study dissolution in a porous layer that exhibits a feature relevant for CO[subscript 2] storage in structural and stratigraphic traps: a finite CO[subscript 2] source along the top boundary that extends only part way into the layer. This feature represents the finite extent of the interface between free-phase CO[subscript 2] pooled in a trap and the underlying brine. Using theory and simulations, we describe the dissolution mechanisms in this system for a wide range of times and Rayleigh numbers, and classify the behaviour into seven regimes. For each regime, we quantify the dissolution flux numerically and model it analytically, with the goal of providing simple expressions to estimate the dissolution rate in real systems. We find that, at late times, the dissolution flux decreases relative to early times as the flow of unsaturated water to the CO[subscript 2] source becomes constrained by a lateral exchange flow though the reservoir. Application of the models to several representative reservoirs indicates that dissolution is strongly affected by the reservoir properties; however, we find that reservoirs with high permeabilities (k ≥ 1 Darcy) that are tens of metres thick and several kilometres wide could potentially dissolve hundreds of megatons of CO[subscript 2] in tens of years.United States. Dept. of Energy (Grant DE-SC0003907)United States. Dept. of Energy (Grant DE-FE0002041)MIT Masdar ProgramMartin Family Fellowship for Sustainabilit

Nebraska Rainbow Trout

Chapter 1 Lethal and Preferred Temperatures of Lake McConaughy Rainbow Trout Versus Domestic Strain Rainbow Trout By R. Vancil, G. Zuerlein and L. Hesse Chapter 2 A Nitrifying Filter-Cooling Condenser System for Total Water Re-use in Cold-Water Fish Holding or Rearing Applications By L. Hesse, G. Zuerlein and R. Vancil Chapter 3 Biochemical Genetic Analysis of Two Strains of Nebraska Rainbow Trout By J. Seeb and L. Wishard The self-sustaining rainbow trout population living in Lake Mcconaughy and the North Platte River tributaries is unique to the Great Plains region. The population spends most of its adult life in the reservoir, but moves into tributary streams to spawn. Two spawning runs occur. The largest is from September through November followed by a reduced migration. in March and April of the following spring. Rainbow trout fingerlings spend about a year in the stream before smolting and migrating to the reservoir. Fishing for Mcconaughy rainbows in the tributaries and reservoir began in the late 1940\u27s. Concern for the maintenance of this fishery prompted several investigations which were directed at development of a management plan. From these studies it was evident that the McConaughy rainbow possessed a selective advantage over hatchery origin fish stocked in the streams and reservoir. Temperatures, normally too high for successful rainbow survival, were often encountered in the streams and the eutrophying Lake McConaughy. This study was designed to compare the temperature tolerance and preference of Mcconaughy rainbow trout with hatchery origin fish. Chapter 1 describes the results of this study. Chapter 2 describes the laboratory facility developed to hold fish for relatively long periods while conducting the experiments. Chapter 3 contains the results of studies designed to characterize the genetic differences between hatchery fish from Massachusetts and the self-sustaining Mcconaughy rainbow trout. The Pacific Fisheries Research Laboratory in Olympia, Washington, was contracted to perform an electrophoresis characterization of the frequency of biochemical genetic variants among the McConaughy and hatchery rainbow groups

Gershgorin disks for multiple eigenvalues of non-negative matrices

Gershgorin's famous circle theorem states that all eigenvalues of a square matrix lie in disks (called Gershgorin disks) around the diagonal elements. Here we show that if the matrix entries are non-negative and an eigenvalue has geometric multiplicity at least two, then this eigenvalue lies in a smaller disk. The proof uses geometric rearrangement inequalities on sums of higher dimensional real vectors which is another new result of this paper

Evolution of a subtilisin-like protease gene family in the grass endophytic fungus Epichloë festucae

<p>Abstract</p> <p>Background</p> <p>Subtilisin-like proteases (SLPs) form a superfamily of enzymes that act to degrade protein substrates. In fungi, SLPs can play either a general nutritive role, or may play specific roles in cell metabolism, or as pathogenicity or virulence factors.</p> <p>Results</p> <p>Fifteen different genes encoding SLPs were identified in the genome of the grass endophytic fungus <it>Epichloë festucae</it>. Phylogenetic analysis indicated that these SLPs belong to four different subtilisin families: proteinase K, kexin, pyrolysin and subtilisin. The pattern of intron loss and gain is consistent with this phylogeny. <it>E. festucae </it>is exceptional in that it contains two kexin-like genes. Phylogenetic analysis in Hypocreales fungi revealed an extensive history of gene loss and duplication.</p> <p>Conclusion</p> <p>This study provides new insights into the evolution of the SLP superfamily in filamentous fungi.</p

Eyelid microcystic adnexal carcinoma

Microcystic adnexal carcinoma is an uncommon cutaneous tumor with multiple synonyms. On cursory microscopic examination, the tumor mimics syringoma and other benign skin adnexal tumors. However, the asymmetric, infiltrative growth pattern clearly sets the lesion apart as carcinoma. The tumor is locally aggressive, with recurrences common, but regional metastases are rare. Histogenesis is controversial. Optimal treatment consists of complete surgical excision with clear surgical margins

Integrative gene-metabolite network with implemented causality deciphers informational fluxes of sulphur stress response

The systematic accumulation of gene expression data, although revolutionary, is insufficient in itself for an understanding of system-level physiology. In the post-genomic era, the next cognitive step is linking genes to biological processes and assembling a mosaic of data into global models of biosystem function. A dynamic network of informational flows in Arabidopsis plants perturbed by sulphur depletion is presented here. With the use of an original protocol, the first blosystem response network was reconstructed from a time series of transcript and metabolite profiles, which, on the one hand, integrates complex metabolic and transcript data and, on the other hand, possesses a causal relationship. Using the informational fluxes within this reconstruction, it was possible to link system perturbation to response endpoints. Robustness and stress tolerance, as consequences of scale-free network topology, and hubs, as potential controllers of homeostasis maintenance, were revealed. Communication paths of propagating system excitement directed to physiological endpoints, such as anthocyanin accumulation and enforced root formation were dissected from the network. An auxin regulatory circuit involved in the control of a hypo-sulphur stress response was uncovered