bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of pityolure for detection and control of Thaumetopoea pityocampa in Israel1
Authors: HALPERIN J. 
Published: April 2008

Trials were carried out with pityolure, the synthetic female sex pheromone of Thaumetopoea pityocampa, to test the various possibilities of its use in the management of the pest. Practical application consists of macromapping of infested and non‐infested areas, early detection of new foci of infestation, and timing of sprays with insecticides. Brief mention is made of possible uses not yet applied in practice, such as control by mating disruption, control by mass trapping and monitoring of the population level.Des essais sur le pityolure, phéromone synthétique sexuelle femelle de Thaumetopoea pityocampa, ont permis de tester diverses possibilités d'utilisation pour la lutte contre cet organisme nuisible. Parmi les applications pratiques sont la macro‐cartographie des lieux infestés ou non infestés, la détection précoce de nouveaux foyers d'infestation et la détermination des dates d'application de pulvérisations d'insecticides. Quelques utilisations possibles mais non encore appliquées sont brièvement mentionnées: lutte par confusion des mâles, lutte par piégeages en masse et contrôle des niveaux de population.
The PICA Strategy for the prevention of losses caused by plagues of Mus domesticus in rural Australia1
Authors: REDHEAD T. , SINGLETON G. 
Published: April 2008

This paper examines the previously defined PICA Strategy for prevention of losses caused by mass outbreaks (plagues) of Mus domesticus in the grain belt of southern and eastern Australia. Such a strategy is considered necessary, in place of the traditional ad hoc response, if losses caused by mouse plagues are to be prevented. The PICA Strategy could be implemented as either site‐PICA or district‐PICA, each of which comprises four steps: (1) prediction of the plague; (2) informing governments, farmers and other managers; (3) control, using a tactical, prophylactic approach, to prevent mouse abundance from reaching plague proportions; (4) assessing the effectiveness of the control operation. Of the four components, prediction of mouse plagues is the key. Presently, a non‐mathematical mechanistic model of mouse plague formation, with above‐average autumn rains as the environmental trigger of each plague, is used. However, the economics and demography of mouse plagues, despite their apparently singular environmental trigger, exhibit a very high degree of spatial and temporal variability. Consequently, farmers and other decision‐makers require site‐specific predictions. Further scientific research into the population biology of house mice in heterogeneous landscapes, and control techniques are both required before the PICA Strategy can be implemented effectively.L'article réexamine la stratégie dite PICA (des mots anglais Prediction‐Information‐Control‐Assessment) pour la réduction des pertes associées aux pullulations de Mus domesticus dans la zone céréalière de l'Australie orientale et méridionale. Le remplacement des mesures ad hoc actuelles par cette stratégie est le seul moyen d'écarter ces pertes. Deux niveaux d'opération sont prévus‐site PICA (au niveau de la localité) et district‐PICA (au niveau de la région), chacun comportant 4 phases: 1) précision de la pullulation; 2) transmission d'informations aux autorités locales, aux agriculteurs et aux autres décideurs; 3) lutte, par approche tactique et prophylactique, destinée à contenir les populations au‐dessous de la pullulation; 4) évaluation de l'efficacité des opérations. La prévision est l'élément‐clé. Actuellement, la stratégie se base sur un modèle mécanistique non mathématique de la pullulation, déclenché par une pluviosité automnale excessive. Toutefois, si le moyen de déclenchement semble être toujours le même, les pullulations sont très variables dans le temps et dans l'espace en ce qui concerne leur importance économique et leur démographie. Les agriculteurs et autres décideurs ont ainsi besoin de prévisions spécifiques à la localité. Il faut ainsi poursuivre la recherche sur la biologie des populations de souris dans un paysage hétérogène, ainsi que sur les méthodes de lutte, pour pouvoir assurer la pleine efficacité de la stratégie PICA.
Fungicide resistance in soil‐borne Phytophthora species1
Authors: LUCAS J. A. , BOWER L. A. , COFFEY M. D. 
Published: April 2008

Systemic fungicides such as the phenylamides and phosphonates have provided new opportunities for chemical control of soil‐borne Phytophthora species. Potential problems in their use include biodegradation in soils, and the emergence of pathogen isolates resistant to these compounds. Resistance to phenylamides is well known in leaf‐infecting Oomycetes, but less is known about the development and relative fitness of resistant isolates among populations of soil‐borne Phytophthora species. Experiments with P. capsici and P. palmivora have shown that stable resistant and virulent isolates can be selected under laboratory conditions. Some mutants resistant to both metalaxyl and fosetyl‐A1 have been recovered, with growth rates and sporulation equivalent to parental wild types. Selected mutants proved able to compete in vivo with fungicide‐sensitive wild types in the absence of the compounds. More information is required to fully evaluate the implications of these results for chemical control of soil‐borne Phytophthora species in the field.Résistance des Phytophthora du sol aux fongicides
Phytophthora root disease of alder in Britain
Authors: GIBBS J. N. 
Published: April 2008

A root disease of common alder caused by Phytophthora sp. is widespread in southern Britain. It is estimated that more than 20 000 trees are seriously affected.Une infection racinaire due àPhytophthora sp. est largement disséminée dans le sud de la Grande‐Bretagne. Plus de 20 000 arbres sont estimés gravement atteints.
A comparison of observed and simulated site response in the Rhône valley
Authors: Roten D. , Fäh D. , Olsen K. B. , Giardini D. 
Published: April 2008

SummarySite effects in the city of Sion in the Rhône valley are analysed from weak motion signals recorded on a dense temporary array. We simulate the recorded events with a 3-D finite difference method for frequencies up to 4 Hz using a recently developed velocity model of the Sion basin.Site-to-reference Fourier spectral ratios are computed from 16 local and regional events. All sites exhibit amplification factors of up to 12 between 0.5 and 0.6 Hz, which can be reproduced by the numerical simulations. By rotating the weak motion to directions parallel and perpendicular to the valley axis, we show that this low-frequency amplification is caused by the SH00 and SV0 fundamental modes of 2-D resonance.Additional peaks of amplification can be observed at higher frequencies, with amplification factors of up to 20 at some sites.Application of the high-resolution frequency-wavenumber and the multiple signal characterization method to the vertical component of recorded and simulated signals show that edge-generated surface waves arriving from almost all directions dominate the wavefield at 1.25 and 2.50 Hz.Peak ground velocities computed from the simulated ground motion show interference patterns that depend strongly on the incidence direction, and the computed amplification of peak ground velocities are generally in agreement with the observations.We conclude that the complex 3-D geometry of the basin needs to be considered to evaluate site effects up to at least 2.5 Hz.
Global‐scale seismic interferometry: theory and numerical examples
Authors: Ruigrok Elmer , Draganov Deyan , Wapenaar Kees 
Published: April 2008

ABSTRACTProgress in the imaging of the mantle and core is partially limited by the sparse distribution of natural sources; the earthquake hypocenters are mainly along the active lithospheric plate boundaries. This problem can be approached with seismic interferometry. In recent years, there has been considerable progress in the development of seismic interferometric techniques. The term seismic interferometry refers to the principle of generating new seismic responses by cross‐correlating seismic observations at different receiver locations. The application of interferometric techniques on a global scale could create sources at locations where no earthquakes occur. In this way, yet unknown responses would become available for the application of travel‐time tomography and surface‐wave dispersion studies. The retrieval of a dense‐enough sampling of source gathers would largely benefit the application of reflection imaging.We derive new elastodynamic representation integrals for global‐scale seismic interferometry. The relations are different from other seismic interferometry relations for transient sources, in the sense that they are suited for a rotating closed system like the Earth. We use a correlation of an observed response with a response to which free‐surface multiple elimination has been applied to account for the closed system. Despite the fact that the rotation of the Earth breaks source‐receiver reciprocity, the seismic interferometry relations are shown to be valid. The Coriolis force is included without the need to evaluate an extra term.We synthesize global‐scale earthquake responses and use them to illustrate the acoustic versions of the new interferometric relations. When the sampling of real source locations is dense enough, then both the responses with and without free‐surface multiples are retrieved. When we do not take into account the responses from the sources in the direct neighborhood of the seismic interferometry‐constructed source location, the response with free‐surface multiples can still be retrieved. Even when only responses from sources at a certain range of epicentral distances are available, some events in the Green's function between two receiver locations can still be retrieved. The retrieved responses are not perfect, but the artefacts can largely be ascribed to numerical errors. The reconstruction of internal events – the response as if there was a source and a receiver on (major) contrasts within the model – could possibly be of use for imaging.With modelling it is possible to discover in which region of the correlation panel stationary phases occur that contribute to the retrieval of events. This knowledge opens up a new way of filtering out undesired events and of discovering whether specific events could be retrieved with a given source‐receiver configuration.
Consistency of the spatial autocorrelation method with seismic interferometry and its consequence
Authors: Yokoi Toshiaki , Margaryan Sos 
Published: April 2008

ABSTRACTWe have cross‐checked the conventional theory of the spatial autocorrelation method and the consequence of seismic interferometry: the retrieval of the elastodynamic Green's function. Their mutual consistency is almost complete. The basic formulas of the conventional spatial autocorrelation theory can be derived by an alternative approach based on the retrieval of the elastodynamic Green's function. The only discrepancy is found with the average of the complex coherence function over azimuth in a wavefield dependent on azimuth. It is hypothesized, in discussion, that this discrepancy is due to the way of representing the wavefield in the background theory of seismic interferometry that can produce only wavefields moderately dependent on azimuth and that the mentioned consequence of seismic interferometry can also only make sense in a wavefield moderately dependent on azimuth.Our field experiment with a wavefield dependent on azimuth showed that the consequence of seismic interferometry in the logical framework of the conventional spatial autocorrelation theory is appropriate under such degrees of approximation as the measure proposed in this study, i.e., the deviation of the total dispersion curves is between about 10 and 16 per cent at the maximum from those averaged over azimuth.The acceptance of the retrieval of Green's function gives a proper physical meaning to the complex coherence function: the real part of the elastodynamic Green's function normalized by its zero‐offset version. This makes it possible to take a deterministic approach rather than the statistical one on which the conventional spatial autocorrelation method is based and gives fruitful new aspects and perspectives. For example, the formula for the multi‐mode case is given and the possibility of exploration of two or three dimensional velocity structures is suggested.
Endothelial nitric oxide synthase is a critical factor in experimental liver fibrosis
Authors: Leung Tung‐Ming , Tipoe George L. , Liong Emily C. , Lau Thomas Y.H. , Fung Man‐Lung , Nanji Amin A. 
Published: April 2008

SummaryReduced expression of endothelial nitric oxide synthase (eNOS) in chronic liver disease can reduce hepatic perfusion and accelerate fibrosis. The relationship between eNOS expression and liver fibrogenesis remains unclear. We investigated whether l‐arginine attenuated chronic liver fibrosis through eNOS expression. Chronic liver injury was induced by administration of carbon tetrachloride (CCl4) to mice for 8 weeks. 5‐Methylisothiourea hemisulphate (SMT), an iNOS inhibitor, or l‐arginine, a NOS substrate were injected subcutaneously. CCl4‐induced hepatotoxicity, oxidative stress and accumulation of collagen were detected in the liver. The expression levels of inducible NOS (iNOS) and nuclear factor kappa‐B (NF‐κB) activity in the liver after CCl4 treatment were increased but eNOS expression and activator protein‐1 (AP‐1) activity were decreased. Both SMT and l‐arginine effectively reduced CCl4 induced oxidative stress and collagen formation, but l‐arginine showed a significantly greater suppression of collagen formation, iNOS expression and NF‐κB activity. l‐Arginine also restored the level of eNOS and AP‐1 activity. l‐Arginine was more effective than SMT in suppressing liver fibrosis. l‐Arginine might improve NO production which facilitates hepatic blood flow and thus retards liver fibrogenesis. Our results showed that the reduced eNOS expression in CCl4‐treated mice was reversed by l‐arginine. Furthermore, l‐arginine also reversed the reduced AP‐1 activity, an eNOS promoter.
Freeze‐substitution: the addition of water to polar solvents enhances the retention of structure and acts at temperatures around –60°C
Authors: BUSER C. , WALTHER P. 
Published: April 2008

SummaryHigh‐pressure freezing followed by freeze substitution and plastic embedding is becoming a more widely used method for TEM sample preparation. Here, we have investigated the influence of solvents, fixative concentrations and water content in the substitution medium on the sample quality of high‐pressure frozen, freeze‐substituted and plastic embedded mammalian cell culture monolayers. We found that the visibility of structural details was optimal with acetone and that extraction increased with both increasing and decreasing solvent polarity. Interestingly, the addition of water to polar solvents increased the sample quality, while being destructive when added to apolar solvents. The positive effect of water addition is saturable in acetone and ethanol at 5%(v/v), but even addition of up to 20% water has no negative effect on the sample structure. Therefore, a medium based on acetone containing fixatives and 5% water is most optimal for the substitution of mammalian cell cultures. In addition, our results suggest that the presence of water is critical for the retention of structure at temperatures around –60°C.
SHORT COMMUNICATION: Microcarriers for high‐pressure freezing and cryosectioning of adherent cells
Authors: HAGEN C. , GRÜNEWALD K. 
Published: April 2008

SummaryA method is described employing microcarrier spheres of cross‐linked dextran for obtaining ultra‐ and semithin vitreous sections from high‐pressure frozen anchorage‐dependent (mammalian) cells. Avoiding trypsination or scraping cells off from the culture surface, the presented approach allows for cryoimmobilization, cryosectioning and cryoelectron microscopy/tomography of frozen‐hydrated cells in an unperturbed manner which is important to preserve the native state of, for instance, the cytoskeleton. Furthermore, our studies on the ‘life cycle’ of Herpes simplex virus in Vero cells demonstrate that cell monolayers on microcarrier beads are well suited for fluorescence microscopic characterization of the sample prior to high‐pressure freezing.
High population differentiation and unusual haplotype structure in a shade‐intolerant pioneer tree species, Zanthoxylum ailanthoides (Rutaceae) revealed by analysis of DNA polymorphism at four nuclear loci
Authors: KAMIYA K. , MORITSUKA E. , YOSHIDA T. , YAHARA T. , TACHIDA H. 
Published: April 2008

AbstractDifferences in demographic history, life‐history traits, and breeding systems affect nucleotide variation patterns. It is expected that shade‐intolerant pioneer tree species have different patterns of genetic polymorphism and population structure than climax species. We studied patterns of nucleotide polymorphism at four putative starch pathway loci (agpSA, agpSB, agpL, and GBSSI) in Zanthoxylum ailanthoides, a shade‐intolerant pioneer tree species that occupies forest gaps in warm‐temperate forests of East Asia. Genetic diversity was lower within each population than among populations, and differentiation among populations was high across the loci (FST = 0.32–0.64), as expected from the insect‐pollinated breeding system and the metapopulation structure of this pioneer species. Numbers of haplotypes were smaller than those expected from the observed numbers of segregating sites. Single haplotypes accounted for more than 47% of all the sampled genes at the respective loci. These variation patterns were incompatible with neutral predictions for populations of a finite island model. Complex population dynamics, such as bottleneck and/or admixture, in the history of this pioneer tree species might have resulted in the observed patterns of genetic variation and population structure, which are different from those of climax wind‐pollinated tree species, such as conifers. In contrast to the other loci investigated in this study, agpL showed nearly no variation in Z. ailanthoides (one singleton only), but there was some extent of variation in a closely related species, Zanthoxylum schinifolium. This suggests possibly a recent selective sweep at or near the locus in Z. ailanthoides.
Temporal changes in kin structure through a population cycle in a territorial bird, the red grouse Lagopus lagopus scoticus
Authors: PIERTNEY STUART B. , LAMBIN XAVIER , MACCOLL ANDREW D. C. , LOCK KERRY , BACON PHILIP J. , DALLAS JOHN F. , LECKIE FIONA , MOUGEOT FRANCOIS , RACEY PAUL A. , REDPATH STEVE , MOSS ROBERT 
Published: April 2008

AbstractPopulations of red grouse (Lagopus lagopus scoticus) undergo regular multiannual cycles in abundance. The ‘kinship hypothesis’ posits that such cycles are caused by changes in kin structure among territorial males producing delayed density‐dependent changes in aggressiveness, which in turn influence recruitment and regulate density. The kinship hypothesis makes several specific predictions about the levels of kinship, aggressiveness and recruitment through a population cycle: (i) kin structure will build up during the increase phase of a cycle, but break down prior to peak density; (ii) kin structure influences aggressiveness, such that there will be a negative relationship between kinship and aggressiveness over the years; (iii) as aggressiveness regulates recruitment and density, there will be a negative relationship between aggressiveness in one year and both recruitment and density in the next; (iv) as kin structure influences recruitment via an affect on aggressiveness, there will be a positive relationship between kinship in one year and recruitment the next. Here we test these predictions through the course of an 8‐year cycle in a natural population of red grouse in northeast Scotland, using microsatellite DNA markers to resolve changing patterns of kin structure, and supra‐orbital comb height of grouse as an index of aggressiveness. Both kin structure and aggressiveness were dynamic through the course of the cycle, and changing patterns were entirely consistent with the expectations of the kinship hypothesis. Results are discussed in relation to potential drivers of population regulation and implications of dynamic kin structure for population genetics.
A Csr‐type regulatory system, including small non‐coding RNAs, regulates the global virulence regulator RovA of Yersinia pseudotuberculosis through RovM
Authors: Heroven Ann Kathrin , Böhme Katja , Rohde Manfred , Dersch Petra 
Published: April 2008

SummaryThe MarR‐type regulator RovA controls expression of virulence genes of Yersinia pseudotuberculosis in response to environmental signals. Using a genetic strategy to discover components that influence rovA expression, we identified new regulatory factors with homology to components of the carbon storage regulator system (Csr). We showed that overexpression of a CsrB‐ or a CsrC‐type RNA activates rovA, whereas a CsrA‐like protein represses RovA synthesis. We further demonstrate that influence of the Csr system on rovA is indirect and occurs through control of the LysR regulator RovM, which inhibits rovA transcription. The CsrA protein had also a major influence on the motility of Yersinia, which was independent of RovM. The CsrB and CsrC RNAs are differentially expressed in Yersinia. CsrC is highly induced in complex but not in minimal media, indicating that medium‐dependent rovM expression is mediated through CsrC. CsrB synthesis is generally very low. However, overexpression of the response regulator UvrY was found to activate CsrB production, which in turn represses CsrC synthesis independent of the growth medium. In summary, the post‐transcriptional Csr‐type components were shown to be key regulators in the co‐ordinated environmental control of physiological processes and virulence factors, which are crucial for the initiation of Yersinia infections.
Systematic functional analysis of calcium‐signalling proteins in the genome of the rice‐blast fungus,Magnaporthe oryzae, using a high‐throughput RNA‐silencing system
Authors: Nguyen Quoc Bao , Kadotani Naoki , Kasahara Seiji , Tosa Yukio , Mayama Shigeyuki , Nakayashiki Hitoshi 
Published: April 2008

SummaryWe developed an RNA‐silencing vector, pSilent‐Dual1 (pSD1), with a convergent dual promoter system that provides a high‐throughput platform for functional genomics research in filamentous fungi. In the pSD1 system, the target gene was designed to be transcribed as a chimeric RNA with enhanced green fluorescent protein (eGFP) RNA. This enabled us to efficiently screen the resulting transformants using GFP fluorescence as an indicator of gene silencing. A model study with the eGFP gene showed that pSD1‐based vectors induced gene silencing via the RNAi pathway with slightly lower efficiency than did hairpin eGFP RNA‐expressing vectors. To demonstrate the applicability of the pSD1 system for elucidating gene function in the rice‐blast fungusMagnaporthe oryzae, 37 calcium signalling‐related genes that include almost all known calcium‐signalling proteins in the genome were targeted for gene silencing by the vector. Phenotypic analyses of the silenced transformants showed that at least 26, 35 and 15 of the 37 genes examined were involved in hyphal growth, sporulation and pathogenicity, respectively, inM. oryzae.These included several novel findings such as thatPmc1‐,Spf1‐ andNeo1‐like Ca2+pumps, calreticulin and calpactin heavy chain were essential for fungal pathogenicity.