Egg dispersion in codling moth: Influence of egg extract and of its fatty acid constituents

Codling moth females (Cydia pomonella, Lepidoptera: Tortricidae) (CM) usually lay single eggs and have a tendency to disperse. In a first experiment we observed that single females exposed to 20 apples distribute their eggs regularly among apples, suggesting a dispersive oviposition behavior. In a dual-choice situation, isolated females avoided oviposition on areas of cardboard treated with a methylene dichloride egg extract at the dose of ca. 1.0 egg equivalent/cm². A strong avoidance was obtained in response to a 20-fold dose, which was accompanied by a significant reduction of total oviposition. Seven major compounds found by GC analyses in the methylene dichloride extract of 2 to 3-day-old eggs were saturated or unsaturated C₁₄-C₁₈ straight-chain fatty acids: myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. This was confirmed by GC-MS analysis of an extract made by ethyl ether. Smaller amounts of three methyl esters were also identified as methyl myristate, methyl palmitate, and methyl stearate. A blend of the seven fatty acids (FA) mimicked rather well the avoidance provoked by the extract, and this avoidance was confirmed by choice between treated and untreated fruits by single females. The treatment of apples with the 7FA mixture induced an aggregative distribution of the eggs among apples. We also found that the amounts of fatty acids harvested in the extract depend on the egg age. Amounts of fatty acids increased until eggs were 4 days old and then decreased before hatching. In this paper we discuss the possible role of simple molecules, such as fatty acids and their esters, as semiochemicals indicative of juvenile tissues.     

Direct Laser Interference Patterning of Zirconia Using Infra-Red Picosecond Pulsed Laser: Effect of Laser Processing Parameters on the Surface Topography and Microstructure

This study investigates the influence of processing parameters when applying direct laser interference patterning (DLIP) on the morphology and microstructure of zirconia surfaces using a 10 ps-pulsed laser source with 1064 nm wavelength. An experimental testing matrix is built with different values of laser fluence (5.7 – 18.2 J cm⁻²) and pulse overlap (66 – 98%). Surface morphology and microstructure are characterized by confocal microscopy and scanning electron microscopy. Homogeneous line-like patterns with periodic spatial repetition of 5.0 µm, with varying depths, widths, and aspect ratio, are fabricated using proper processing parameters (5.7 – 7.6 J cm⁻² and 92 – 96%). Structures with maximum depth of 1.5 µm and sharp edges are obtained (7.6 J cm⁻² and 96% overlap). Ablated regions presented a morphology typical of photophysical ablation mechanism, with signs of molten material at the surface. Sub-micrometric pores and nanodroplets are registered for all conditions, while sub-micrometric cracks developed only for higher fluences. A processing window conducing to homogenous DLIP structures is set based on experimental data. Periodic structures with multiscale topographic features are successfully obtained on zirconia surfaces using DLIP technology in this study. These outcomes open new perspectives for fabrication of multifunctional zirconia surfaces for advanced biomedical and engineering applications.     

Wheat Phosphorus Availability: 1—In VitroStudy; Factors Affecting Endogenous Phytasic Activity and Phytic Phosphorus Content

Phytasic activity and phytic P content, which are important factors in determining the availability of P, were measured in 56 wheat samples. The different agronomic and genetic factors which could have an influence on these two variables were studied, specifically N and/or P fertilisation, date of harvest, preharvest sprouting and variety of French wheat. Phytasic activity ranged from 206 to 775mUg⁻¹, with an average of 508mUg⁻¹ and a standard deviation of 109mUg⁻¹. Only the variety of wheat appeared as a significant factor explaining the endogenous phytasic activity ( P =0·006). The phytic P content varied between 0·92 and 2·80gkg⁻¹ DM, with an average of 2·18gkg⁻¹ and a standard deviation of 0·35gkg⁻¹ DM. None of the factors studied significantly affected the phytic P content of the wheat. This content was correlated with the total P content ( r =0·56; P< 0·05). The activity of the endogenous phytase was independent of the quantity of its substrate, the phytic phosphorus of the kernels of wheat.     

The Candida albicans PKC1 gene encodes a protein kinase C homolog necessary for cellular integrity but not dimorphism

Using a DNA fragment derived from the Saccharomyces cerevisiae protein kinase C gene (PKC1) as a probe to screen an ordered array library of genomic DNA from the dimorphic pathogenic fungus Candida albicans, the C. albicans PKC1 gene (CaPKC1) was isolated. The CaPKC1 gene is predicted to encode a protein of 1079 amino acids with 51% sequence identity over the entire length with the S. cerevisiae Pkc1 protein and is capable of functionally complementing the growth defects of a S. cerevisiae pkc1Δ mutant strain on hypo-osmotic medium. Deletion of both endogenous copies of the CaPKC1 gene in diploid C. albicans cells resulted in an osmotically remedial cell lysis defect of both the budding and the hyphal growth form and morphologically aberrant cells of the budding form. Despite these abnormalities, the transition between the two growth forms of C. albicans occurred normally in pkc1/pkc1 double disruptants. Capkc1p was modified at its C-terminus with two repeats of the Staphylococcus aureus protein A IgG-binding fragment (ZZ-sequence tag) and partially purified by chromatography on DEAE–Sepharose and IgG–Sepharose. In vitro, Capkc1p preferably phosphorylated the S. cerevisiae Pkc1p pseudosubstrate peptide and myelin basic protein, but not histones, protamine or dephosphorylated casein, and failed to respond to cofactors known to activate several mammalian PKC isozymes.     

Maximizing the Robustness of TDMA Networks with Applications to TTP/C

In this study we show how one can use Fault-Tolerant Units (FTU) in an optimal way to make a TDMA network robust to bursty random perturbations. We consider two possible objectives. If one wants to minimize the probability of losing all replicas of a given message, then the optimal policy is to spread the replicas over time. This is proved using convexity properties of the loss probability. On the contrary if one wants to minimize the probability of losing at least one replica, then the optimal solution is to group all replicas together. This is proved by using majorization techniques. Finally we show how these ideas can be adapted for the TTP/C protocol. Bruno Gaujal is a research director at INRIA Rhone-Alpes since 2003 where he is the leader of the group on large scale networks. He has held several positions in INRIA Sophia-Antipolis, Loria and ENS-Lyon before. His main interest are performance evaluation and control of discrete event dynamic systems. Nicolas Navet received the M.S. in Computer Science from the University of Berlin (Germany) in 1994 and the PhD in Computer Science from the University of Nancy in 1999. Before joining the INRIA (LORIA Lab.) in November 2000, he was research scientist at Gemplus Software. His research interests include scheduling theory, the design of communication protocols for real-time and fault-tolerant data transmission and probabilistic risk evaluation when transient faults may occur (for instance, due to electromagnetic interferences). More information on his work can be found at url http://www.loria.fr/~nnavet.     

Umfassende Prüfung von Holzschutzmitteln gegen holzzerstörende Pilze und Tiere

Zusammenfassung Die Vietsciligheit der in Frage hommenden Anforderungen veriangt cine gleichzeitige Heranzichung biologischer, chemisch-physikalischer und technisch-mechanischer Verfahren.—für die Prüfung der “erforderlichen” und “nachteiliger” Wirkung von Holzschutmitteln werden Richtlinien angegeben. (Mitteilung aus dem Staatlichen materialprüfungsamt Berlin-Dahlem, Institut für Werkstoff-Biologie.)     

Object exploration, habituation, and response to a spatial change in rats following septal or medial frontal cortical damage.

Normal rats and rats sustaining septal or medial frontal cortex lesions were compared in experiments dealing with object exploration, habituation, and reaction to novelty (measured by renewed exploration following a spatial change). Normal rats exhibited high levels of initial exploratory activity which decreased over time. Folowing a spatial change, they reinvestigated both the displaced object and the nondisplaced ones. Frontal animals were similar to normal subjects with respect to their initial exploratory level and habituation pattern. However, frontal rats reexplored only the displaced object and completely neglected the nondisplaced ones. In contrast, the behavioral pattern displayed by septal rats was markedly different from that of normal and frontal animals. Septal rats had lower levels of initial exploratory activity, did not habituate over time, and failed to react to either displaced or nondisplaced objects. These results show that although the septo-hippocampal complex and the medial frontal cortex may share some common function in spatially organized behaviors, both structures have unique roles. Some hypotheses about the possible basic processes subtended by the septal area or the medial frontal cortex are briefly mentioned and discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Odor control during post-digestion processing of biosolids through bioaugmentation of anaerobic digestion.

The effects of bioaugmenting anaerobic biosolids digestion with a commercial product that contained selected strains of bacteria from genera Bacillus, Pseudomonas, and Actinomycetes, along with ancillary organic compounds containing various micronutrients were evaluated. The main objective of the study was to investigate the effects of bioaugmentation specifically on the performance of methanogenesis during anaerobic digestion, as well as on the generation and fate of odor-causing compounds during the storage of the digested biosolids. The bench-scale digester with 5 g/L bioaugment generated 29% more net CH4 than a control during the eight weeks of operation. In addition, the average residual propionic acid concentration in the bioaugmented digester was 46% lower than that in the control. The biosolids digested in the bioaugmented digester generated a negligible amount of methyl mercaptan (CH3SH) during 10 days of post-digestion storage, while CH3SH concentration in the control reached nearly 300 ppmv during the same period. Similarly peak dimethyl sulfide (CH3SCH3) generated by stored biosolids from the bioaugmented digester was only 37% of that from the control. Similar results were obtained in a subsequent short term study designed to confirm the repeatability of the findings.     

Perspectives nouvelles pour la prise en compte des alcali-réactions dans le calcul des structures

Résumé Les réactions alcalis-granulats sont des processus physico-chimiques internes pouvant induire des gonflements et des fissurations dans les structures en béton. Les mécanismes de ces réactions sont très complexes et encore imparfaitement compris. Dans le but de décrire la durabilité du béton, les processus physico-chimiques et mécaniques doivent être pris en compte par l'intermédiaire de la thermodynamique des processus irréversibles. Une telle approche n'est pas suffisante à cause de la distribution aléatoire des sites réactifs; aussi, dans l'optique d'un traitement numérique, un couplage avec une approche probabiliste est nécessaire.

---

Summary Alkali-aggregate reactions are internal physico-chemical processes which can induce expansion and cracking in concrete structures. The mechanisms of these reactions are complicated and imperfectly understood. In attempting to describe the durability of concrete, physico-chemical and mechanical processes may be taken into account by the use of the thermodynamics of irreversible processes. Such an approach is not sufficient, however, because of the random distribution of the reactive sites. A numerical model based on finite element analysis is put forward to aid evaluation.