Modelling the Persistence of Quiescent Conidia of the Entomopathogenic Hyphomycete Paecilomyces fumosoroseus Exposed to Solar Radiation

Persistence of conidia of the entomopathogenic fungus Paecilomyces fumosoroseus exposed to artificial and solar radiation at a constant temperature was studied by monitoring the ability to germinate and to form colonies (colony - forming units , CFUs) . The photic effect of radiation on each of these variables was modelled by a decreasing function of UVB irradiation ( in J m 2) . Germination ability was represented by a logistic function and viability (log CFU) by an infinitely decreasing function . Experiments carried out under artificial conditions , at three different UVB irradiances ( from 0 . 3 to 1 . 6 W m 2) , similar to those observed in nature , confirmed the adequacy of the predictor variable and of the functions chosen for describing these data . The proposed models appeared to be irradiance independent . Under solar radiation , the models were able to describe data collected on three different summer days in France (48 o 51 N , 2 o 06 E) . However , it took a greater amount of solar UVB radiation to produce the same effect as that achieved indoors . This could be explained by differences in radiation spectra . For each model , one set of parameters was sufficient for representing all three sets of data: this constitutes an initial validation of the models proposed .     

KCNE1 is an auxiliary subunit of two distinct ion channel superfamilies

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The controversial origin of the abdominal appendage‐like processes in immature insects: Are they true segmental appendages or secondary outgrowths? (Arthropoda hexapoda)

In this article, I review the major characteristics of different types of appendage‐like processes that develop at the abdominal segments of many immature insects, and I discuss their controversial morphological value. The main question is whether the abdominal processes are derived from segmental appendages serially homologous to thoracic legs, or whether they are “secondary” outgrowths not homologous with true appendages. Morphological and embryological data, in particular, a comparison with the structure and development of the abdominal appendages in primitive apterygote hexapods, and data from developmental genetics, support the hypothesis of appendicular origin of many of the abdominal processes present in the juvenile stages of various pterygote orders. For example, the lateral processes, such as the tracheal gills in aquatic nymphs of exopterygote insects, are regarded as derived from lateral portions of appendage primordia, homologous with the abdominal styli of apterygotan insects; these processes correspond either to rudimentary telopodites or to coxal exites. The ventrolateral processes, such as the prolegs of different endopterygote insect larvae, appear to be derived from medial portions of the appendicular primordia; they correspond to coxal endites. These views lead to the rejection of Hinton's hypothesis (Hinton [1955] Trans R Entomol Soc Lond 106:455–545) according to which all the abdominal processes of insect larvae are secondary outgrowths not derived from true appendage anlagen. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.     

Comparaisons des séquences d'ADN hautement répétées chez l'homme et diverses espèces de primates

Highly repeated DNA sequences from man, five other primate species and rat were compared using five restriction endonucleases. Calculations of a similarity index based on the mobility of various bands indicate that man, chimpanzee and baboons are very similar. The sequences of the genomes studied have apparently been reorganized during primate evolution.     

Effects of residency training in family medicine v. internship training on professional attitudes and practice patterns.

OBJECTIVES: To determine whether the professional attitudes and practice patterns of physicians with residency training in family medicine differ from those of generalists with internship training. DESIGN: Mail survey conducted in 1985-86. SETTING: Province of Quebec. PARTICIPANTS: A stratified random sample of French-speaking family and general practitioners who graduated after 1972 (325 physicians with residency training and 304 with internship training) (response rate 82%). MAIN RESULTS: Physicians with residency training were 3 years younger on average than those with internship training, were more likely to be female (38% v. 18%, p less than 0.001) and were more likely to work on a salaried basis in CLSCs (public community health centres) (36% v. 14%, p less than 0.001). Even after these confounding factors were controlled for, physicians with residency training seemed to be more sensitive to the psychosocial aspects of patient care and tended to attach more importance to informing patients about useful materials and resources concerning their health problems. They were not, however, more likely to value health counselling or integrate it in medical practice. CONCLUSION: Our findings provide some evidence that the new requirement that physicians complete a residency in family medicine to obtain medical licensure in general practice in Quebec may foster a more patient-centred approach to health care.     

Biotic and abiotic determinants of the formation of ant mosaics in primary Neotropical rainforests

1. Ants are widespread in tropical rainforests, including in the canopy where territorially dominant arboreal species represent the main part of the arthropod biomass. 2. By mapping the territories of dominant arboreal ant species and using a null model analysis and a pairwise approach this study was able to show the presence of an ant mosaic on the upper canopy of a primary Neotropical rainforest (c. 1 ha sampled; 157 tall trees from 28 families). Although Neotropical rainforest canopies are frequently irregular, with tree crowns at different heights breaking the continuity of the territories of dominant ants, the latter are preserved via underground galleries or trails laid on the ground. 3. The distribution of the trees influences the structure of the ant mosaic, something related to the attractiveness of tree taxa for certain arboreal ant species rather than others. 4. Small‐scale natural disturbances, most likely strong winds in the area studied (presence of canopy gaps), play a role by favouring the presence of two ant species typical of secondary formations: Camponotus femoratus and Crematogaster levior, which live in parabiosis (i.e. share territories and nests but lodge in different cavities) and build conspicuous ant gardens. In addition, pioneer Cecropia myrmecophytic trees were recorded.