Cilia in the head of hornets: form and function

In the head of the Oriental hornet, beneath the cuticle, there are plaques of hair cells. These are distributed throughout the upper front part of the head; to wit: in the region of the vertex (i.e., around and behind the ocelli), in the genae around and behind the compound eyes (the ommatidia), and in the region of the forehead or frons. These hair cells are arranged with their thin whip-like part (i.e., cilia) directed outward and morphologically fall into three distinct groups: type (a) thin elongated cilia connected to each other alongside by side-links; type (b) thin elongated cilia of which two or more interconnect at their distal ends via a delicate nerve fiber bearing a knob at its center; and type (c) shorter and thicker cilia that roughly resemble a triangular thorn and are also interconnected by a thin thread, which, however, bears a ball rather then a knob at its center. The knob in the one case and the ball in the other vary in their diameter, but in both instances the interconnecting elements, be they nerve fibers or threads, are seemingly multidirectional. Beneath the frons, in the region of the coronal suture, the hair cells (cilial plaques) are inwardly directed and bear a large trachea at their center. Presumably, the "weighted" cilial cells that are directed toward the exterior of the body aid the hornet in navigation and gravity determination whereas the inwardly directed ciliary cells may possibly serve in acoustic communication. Another element worthy of mention within the hair cells are yellow granules (yg). These yg's originate from the whip-like portion of the ciliary cells that are distributed beneath the frons plate, and also in the yellow stripes of the gastral cuticle. Conceivably, these yellow granules, in both cases, may play a role in the absorption and storage of solar energy. In summary, ciliary structures are involved in the hornet in gravity sensing, in acoustical communication and in light sensing, i.e., with some similarity with what happens in vertebrates in the inner ear and in the photoreceptor.     

Impact of Phenolic Compounds and Related Enzymes in Sorghum Varieties for Resistance and Susceptibility to Biotic and Abiotic Stresses

Contents of phenolic compounds and related enzymes before and after sorghum grain germination were compared between varieties either resistant or susceptible to biotic (sooty stripe, sorghum midge, leaf anthracnose, striga, and grain molds) and abiotic (lodging, drought resistance, and photoperiod sensitivity) stresses. Independent of grain germination, sorghum varieties resistant to biotic and abiotic stresses had on average higher contents of proanthocyanidins (PAs), 3-deoxyanthocyanidins (3-DAs), and flavan-4-ols than susceptible varieties. Results show that content of 3-DAs is a good marker for sorghum resistance to both biotic and abiotic stresses because it correlates with resistance to all stresses except for photoperiod sensitivity. The second good marker for stress resistance is content of PAs. Total phenolic compounds and the activities of related enzymes are not good markers for stress resistance in sorghum grains.     

Effect of Nonlinear Elasticity on Measured Fatigue Data and Lifetime Estimations of Optical Fibers

The compressive stress–strain relation in optical fiber, which is important for a fiber during bending, is shown experimentally to be an asymmetric continuation of the already known nonlinear relation in the tensile region. Measured strengths of optical fibers in fatigue experiments can be 50% higher because of nonlinear corrections. Consequently decreases in measured corrosion susceptibilities, up to 10%, result in estimated fiber lifetimes, which decrease by an order of magnitude. The elastic line of a fiber inserted in a two-point-bending testing apparatus, however, is hardly influenced by nonlinear elastic effects.     

Computing Cartan subalgebras of Lie algebras

We consider the algorithmic problem of computing Cartan subalgebras in Lie algebras over finite fields and algebraic number fields. We present a deterministic polynomial time algorithm for the case when the ground fieldk is sufficiently large. Our method is based on a solution of a linear algebra problem: the task of finding a locally regular element in a subspace of linear transformations. Also, we give a polynomial time algorithm for restricted Lie algebras over arbitrary finite fields. Both methods require an auxiliary procedure for finding non-nilpotent elements in subalgebras. This problem is also treated. Computational experiences are discussed at the end of the paper.Research supported in part by Hungarian National Foundation for Scientific Research grants T016503 and F4116     

Nanocrystal core high-density lipoproteins: a multimodality contrast agent platform

High density lipoprotein (HDL) is an important natural nanoparticle that may be modified for biomedical imaging purposes. Here we developed a novel technique to create unique multimodality HDL mimicking nanoparticles by incorporation of gold, iron oxide, or quantum dot nanocrystals for computed tomography, magnetic resonance, and fluorescence imaging, respectively. By including additional labels in the corona of the particles, they were made multifunctional. The characteristics of these nanoparticles, as well as their in vitro and in vivo behavior, revealed that they closely mimic native HDL.     

Quantitative 13C NMR spectroscopic studies on the equilibrium of formaldehyde with its releasing cosmetic preservatives

The aim of our study was to show that NMR spectroscopy is an excellent method to obtain reliable information about the equilibrium between free formaldehyde and its formaldehyde releasers. For this purpose, we compared several O- and N-formal-based formaldehyde releasers used in industrial and consumer products. The underlying chemical structures as well as the release of formaldehyde were followed quantitatively as a function of the pH and dilution. It was shown that only the amide-based N-formals are a reservoir for formaldehyde in the concentrations normally used in cosmetic products, whereas O-formals and the amine-based N-formals decompose completely. Since NMR spectroscopy does not affect the equilibrium between free and bound formaldehyde, we think that it is the only method for unequivocal determination of free formaldehyde. Measurements on finished products showed that free formaldehyde can be quantified down to concentrations as low as approximately 0.002 wt % in an acceptable measuring time.     

Three-dimensional morphology of GaP-GaAs nanowires revealed by transmission electron microscopy tomography

We have investigated the morphology of heterostructured GaP-GaAs nanowires grown by metal-organic vapor-phase epitaxy as a function of growth temperature and V/III precursor ratio. The study of heterostructured nanowires with transmission electron microscopy tomography allowed the three-dimensional morphology to be resolved, and discrimination between the effect of axial (core) and radial (shell) growth on the morphology. A temperature- and precursor-dependent structure diagram for the GaP nanowire core morphology and the evolution of the different types of side facets during GaAs and GaP shell growth were constituted.     

Social categorization and perceptual judgment of size: When perception is social.

Social knowledge may affect not only people's thoughts and judgments but also their actual perceptions of physical magnitude. The physical magnitude of a stimulus is perceived in a relative way, comparing the magnitude of the target surrounding context stimuli. Because similar objects invite comparison processes more easily than dissimilar objects ("similarity breeds comparability"), social knowledge can affect judgments of physical magnitude by determining what is perceived as (dis) similar. In Experiment 1, the authors show that social categorizations that are based on physical cues (e. g., gender) may affect the magnitude of perceptual contrast effects (the Ebbinghaus illusion). More important, in Experiment 2, the influence of social categorizations that have no physical bases is shown to affect the magnitude of perceptual contrast effects. Implications of these findings for theories of social knowledge effects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of Grammatical Gender and Semantics in German Word Production.

Semantic substitution errors (e.g., saying "arm" when "leg" is intended) are among the most common types of errors occurring during spontaneous speech. It has been shown that grammatical gender of German target nouns is preserved in the errors (E. Mane, 1999). In 3 experiments, the authors explored different accounts of the grammatical gender preservation effect in German. In all experiments, semantic substitution errors were induced using a continuous naming paradigm. In Experiment 1, it was found that gender preservation disappeared when speakers produced bare nouns. Gender preservation was found when speakers produced phrases with determiners marked for gender (Experiment 2) but not when the produced determiners were not marked for gender (Experiment 3). These results are discussed in the context of models of lexical retrieval during production. (PsycINFO Database Record (c) 2010 APA, all rights reserved)