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Selected AbstractsAscomycete communities in the rhizosphere of field-grown wheat are not affected by introductions of genetically modified Pseudomonas putida WCS358rENVIRONMENTAL MICROBIOLOGY, Issue 11 2005Mareike Viebahn Summary A long-term field experiment (1999,2002) was conducted to monitor effects on the indigenous microflora of Pseudomonas putida WCS358r and two transgenic derivatives constitutively producing phenazine-1-carboxylic acid (PCA) or 2,4-diacetylphloroglucinol (DAPG). The strains were introduced as seed coating on wheat into the same field plots each year. Rhizosphere populations of ascomycetes were analysed using denaturing gradient gel electrophoresis (DGGE). To evaluate the significance of changes caused by the genetically modified microorganisms (GMMs), they were compared with effects caused by a crop rotation from wheat to potato. In the first year, only the combination of both GMMs caused a significant shift in the ascomycete community. After the repeated introductions this effect was no longer evident. However, cropping potato significantly affected the ascomycete community. This effect persisted into the next year when wheat was grown. Clone libraries were constructed from samples taken in 1999 and 2000, and sequence analysis indicated ascomycetes of common genera to be present. Most species occurred in low frequencies, distributed almost evenly in all treatments. However, in 1999 Microdochium occurred in relatively high frequencies, whereas in the following year no Microdochium species were detected. On the other hand, Fusarium -like organisms were low in 1999, and increased in 2000. Both the DGGE and the sequence analysis revealed that repeated introduction of P. putida WCS358r had no major effects on the ascomycete community in the wheat rhizosphere, but demonstrated a persistent difference between the rhizospheres of potato and wheat. [source] Fungal pathogens associated with melon collapse in Spain,EPPO BULLETIN, Issue 2 2000J. García-Jiménez Spain produces 43 200 ha of melons with a considerable export to European markets. In the last 10 years, melon cultivation in Spain has decreased more than 40% due mainly to collapse of the vines caused by soil-borne diseases. Serious economic losses have resulted. In order better to understand the aetiology of this disease, a survey of 217 melon fields throughout the melon production areas of Spain was conducted from 1987 to 1996 to analyse the fungal population associated with roots. In addition, the presence of melon necrotic spot carmovirus (MNSV) was studied in 93 fields. This virus is present mainly in southeastern Spain. The predominant fungal species isolated from 82.5% of sampled fields with symptoms of collapse was Acremonium cucurbitacearum. Roots affected by this fungus show corky brown areas soon after transplanting. Small secondary roots and root hairs become necrotic, although there is continuous production of new rootlets. This process continues until the late stages of the disease. As the fruits approach maturity, the entire plant wilts and dies. Other fungal species associated with melon collapse are: Monosporascus cannonballus (isolated from 29.5% of sampled fields), Macrophomina phaseolina (32.7%) and Rhizoctonia solani (31.8%). Of these, the incidence of M. cannonballus isolated from diseased melons has increased substantially over the past 10 years. Melon collapse in Spain is complex because several fungi capable of causing collapse of the vines are prevalent and often isolated from roots in the same field. In addition, other minor pathogens, such as Rhizopycnis vagum and Plectosporium tabacinum, are frequently isolated from symptomatic vines and may also contribute to the death of the plants. [source] Should people with a history of an eating disorder work as eating disorder therapists?EUROPEAN EATING DISORDERS REVIEW, Issue 5 2005Craig Johnston Abstract Much recent attention has focused on the fitness to practise of health professionals. Patients expect their care to be provided by therapeutic staff who can give support and guidance without unhelpful subjective influence. On the other hand, those recovered from health problems expect their employment prospects to be free of discrimination. Eating disorder services increasingly encourage patient and public involvement in service design and monitoring but reservations are sometimes expressed about employing staff who have themselves suffered with an eating disorder. This survey canvassed the views of patients, carers and professionals on the suitability of employing people with a history of an eating disorder as therapists in the same field. With some reservations (mainly from professionals), there was a widespread belief that those who had recovered would have therapeutic advantages as a result of their experience. Therapists with a current eating disorder, however, were thought to lack objectivity and to be vulnerable. Current UK policies on employment appear unnecessarily discriminatory and stigmatizing. Copyright © 2005 John Wiley & Sons, Ltd and Eating Disorders Association. [source] Re-evaluation of the liming-fertilization interaction in grasslands on poor and acid soilsGRASS & FORAGE SCIENCE, Issue 2 2010V. Poozesh Abstract The effect of surface liming on herbage production in permanent grasslands is rather uncertain. To better understand the effect of liming on the grassland, a study was made with a field experiment and a pot experiment with soil from the same field. In the field, the effects of liming and NPK fertilization on the production and composition of the vegetation were studied. In pots, the effects of liming and phosphate fertilization on different grass species were analysed. The effect of NPK fertilization (+3·96 t ha,1) on the production of the original grassland was greater than that of liming (+0·68 t ha,1), which was only observed (P < 0·05) on the unfertilized plots. Liming increased the total number of species and the proportion of dicotyledons. After replacing the semi-natural community with Dactylis glomerata L., the effects of liming (+2·37 t ha,1) and fertilization (+6·52 t ha,1) were increased. These results, together with those of the pot trial, show the important role of phosphorus in the fertilization effect, and are interpreted as a protective effect of P against aluminium toxicity. [source] Comparisons of Isolates of Fusarium avenaceum from White Lupin and Other Crops by Pathogenicity Tests, DNA Analyses and Vegetative Compatibility TestsJOURNAL OF PHYTOPATHOLOGY, Issue 4 2000K. Satyaprasad Isolates of Fusarium avenaceum, mostly from crops of white lupin or wheat, were tested for pathogenicity on white lupin and wheat plants and compared by DNA tests and, in a limited study, vegetative compatibility. Most of the 80 isolates were pathogenic on both plant species after inoculation on shoot bases. Disease severity was greater at higher incubation temperatures that ranged from 15/10°C to 25/20°C (day/night temperatures). Isolates from lupin crops tended to be more pathogenic, on average, on lupins than on cereals. Polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the internal transcribed spacer region of the rDNA distinguished two groups of isolates that occurred in different proportions among isolates from lupins and cereal crops. Random amplified polymorphic DNA (RAPD)-PCR analyses indicated considerable genetic variation among isolates, but there was some similarity among groups of isolates from populations in the same field. Genetic diversity was confirmed by a high degree of vegetative incompatibility among 20 isolates using nitrate nonutilizing mutants. There were no relationships among pathogenicity, RFLP group, RAPD group and vegetative compatibility group. Zusammenfassung Fusarium-avenaceum -Isolate, die überwiegend von Weißier Lupine oder Weizen stammten, wurden hinsichtlich ihrer Pathogenität für Weißie Lupine und Weizenpflanzen getestet und durch DNA-Tests verglichen. In einer kleineren Studie wurde zudem ihre vegetative Kompatibilität geprüft. Die meisten der 80 Isolate waren nach Inokulation der Stengel-bzw. Halmbasis für beide Pflanzenarten pathogen. Bei hohen Inkubationstemperaturen im Bereich von 15/10°C bis 25/20°C (Tag/Nacht-Temperaturen) war der Befall stärker. Von Lupinen stammende Isolate waren im Durchschnitt stärker pathogen für Lupinen als für Getreide. Eine PCR-RFLP-Analyse der Internal-transcribed-spacer-Region der rDNA teilte die Isolate in zwei Gruppen, die bei den Isolaten von Lupinen und Getreide in verschiedenen Anteilen vertreten waren. RAPD-PCR-Analysen zeigten eine beträchtliche genetische Variation bei den Isolaten, aber auch gewisse Ähnlichkeiten bei den Isolatgruppen, die von Populationen im selben Feld stammten. Die genetische Diversität wurde auch durch ein hohes Ausmaßi an vegetativer Inkompatibilität bei 20 Isolaten deutlich; hier wurden Nitrat nicht verwertende Mutanten verwendet. Zwischen Pathogenität, RFLP-Gruppe, RAPD-Gruppe und vegetativer Kompatibilitätsgruppe bestanden keine Beziehungen. [source] Counting individual galaxies from deep 24-,m Spitzer surveysMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006G. Rodighiero ABSTRACT We address the question of how to deal with confusion-limited surveys in the mid-infrared (MIR) domain by using information from shorter-wavelength observations over the same sky regions. Such information, once applied to apparently extended MIR sources, which are indeed ,blends' of two or more different sources, allow us to disentangle the single counterparts and to split the measured flux density into different components. We present the application of this method to the 24-,m Spitzer archival data in the Great Observatories Origins Deep Survey ELAIS-N1 (GOODS EN1) test field, where apparently extended, ,blended' sources constitute about 20 per cent of a reliable sample of 983 sources detected above the 5, threshold down to 40 ,Jy. As a shorter-wavelength data set, we have considered the public Infrared Array Camera (IRAC) images and catalogues of the same field. We show that the 24-,m sample is almost unbiased down to ,40 ,Jy and the careful application of the deblending procedure does not require any statistical completeness correction (at least at the flux level considered). This is probed by direct comparison of our results with results in the literature that analysed the same data set through extensive Monte Carlo simulations. The extrapolation of the source counts down to fainter fluxes suggests that our 24-,m sample is able to resolve ,62 per cent of the cosmic background down to a flux level of 38 ,Jy. [source] Cultivar preference exhibited by two sympatric and genetically distinct populations of the soybean fungal pathogen Phialophora gregata f.sp. sojaePLANT PATHOLOGY, Issue 2 2005X. Meng Phialophora gregata f.sp. sojae, a soilborne vascular pathogen causing brown stem rot of soybean, has been divided into A and B populations based on variation in the intergenic spacer region of nuclear rDNA (rDNA marker). The A and B populations correlate with defoliating and nondefoliating pathotypes, respectively. In this study, eight additional polymorphic anonymous marker loci (five inter simple sequence repeat loci and three long-primer random amplified polymorphic DNA loci) were identified and applied to a total of 189 isolates. Alleles of these eight loci were invariant within, but different between the A and B populations, providing further evidence that the rDNA marker identifies genetically distinct populations. The two populations were sympatric, residing not only in the same field, but also in the same plants under field conditions. Representative strains of the two populations, when used individually in inoculations, infected both resistant cv. Bell and susceptible cv. Sturdy. However, when the same representatives of the two populations were mixed in a 1 : 1 ratio and used as a mixed inoculum in a competitive bioassay, differential cultivar preference was revealed using PCR detection of populations in infected plants. Population A was detected significantly more often (18 out of 24 plants) in the susceptible cv. Sturdy, whereas population B was detected significantly more often (17 out of 24 plants) in the resistant cv. Bell, corroborating earlier field studies. This is the first controlled experiment to demonstrate a differential host preference of P. gregata f.sp. sojae toward different cultivars of the same host species. Unification of terminologies used in P. gregata f.sp. sojae is discussed. [source] Editing as a psychological practiceTHE JOURNAL OF ANALYTICAL PSYCHOLOGY, Issue 3 2006John Beebe Abstract:, The experience of the Jungian analyst in the role of editor of manuscripts by creative colleagues is examined. Historical precedents include Michael Fordham's editorial correspondence with Jung around the latter's synchronicity essay; Jung's handling of manuscripts submitted by Sabina Spielrein to the Jahrbuch für psychoanalytische und psychopathologische Forschungen and various authors to the Zentralblatt für Psychotherapie und ihre Grenzgebiete, and the author's close editing of a paper submitted by Andrew Samuels to the Journal of Analytical Psychology. In addition to mustering an adequate amount of generosity, erudition, and availability, the analytic editor must know how to clarify a psychological argument and to gauge the psychological impact of the written text. Notwithstanding transference/countertransference phenomena that can emerge around issues of competition, envy, and territoriality when author and editor are also fellow-authors working in the same field, the editor needs to be comfortable about serving as the author's selfobject and midwife. From an analytic perspective, although communicating decisions about the best way to put ideas into words can sometimes attract transference to the editor, the more profound transference that analysts experience in the editing situation is toward the text being edited, which helps to motivate donated time spent caring for journal manuscripts. [source] Supersoft sources in M31: Comparing the XMM-Newton deep survey, ROSAT and Chandra catalogues,ASTRONOMISCHE NACHRICHTEN, Issue 2 2010H. Stiele Abstract To investigate the transient nature of supersoft sources (SSSs) in M 31, we compared SSS candidates ofthe XMM-Newton Deep Survey, ROSAT PSPC surveys and the Chandra catalogues in the same field. We found 40 SSSs in the XMM-Newton observations. While 12 of the XMM-Newton sources were brighter than the limiting flux of the ROSAT PSPC survey, only two were detected with ROSAT ,10 yr earlier. Five correlate with recent optical novae which explains why they were not detected by ROSAT. The remaining 28 XMM-Newton SSSs have fluxes below the ROSAT detection threshold. Nevertheless we found one correlation with a ROSAT source, which had significantly larger fluxes than during the XMM-Newton observations. Ten of the XMM-Newton SSSs were detected by Chandra with <1, ,6yr between the observations. Five were also classified as SSSs by Chandra. Of the 30 ROSAT SSSs three were confirmed with XMM-Newton, while for 11 sources other classifications are suggested. Of the remaining 16 sources one correlates with an optical nova. Of the 42 Chandra very-soft sources five are classified as XMM-Newton SSSs, while for 22 we suggest other classifications. Of the remaining 15 sources, nine are classified as transient by Chandra, one of them correlates with an optical nova. These findings underlined the high variability of the sources of this class and the connection between SSSs and optical novae. Only three sources, were detected by all three missions as SSSs. Thus they are visible for more than a decade, despite their variability (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||