Regional and hemispheric determinants of language laterality: Implications for preoperative fMRI.

Language is typically a function of the left hemisphere but the right hemisphere is also essential in some healthy individuals and patients. This inter-subject variability necessitates the localization of language function, at the individual level, prior to neurosurgical intervention. Such assessments are typically made by comparing left and right hemisphere language function to determine "language lateralization" using clinical tests or fMRI. Here, we show that language function needs to be assessed at the region and hemisphere specific level, because laterality measures can be misleading. Using fMRI data from 82 healthy participants, we investigated the degree to which activation for a semantic word matching task was lateralized in 50 different brain regions and across the entire cortex. This revealed two novel findings. First, the degree to which language is lateralized across brain regions and between subjects was primarily driven by differences in right hemisphere activation rather than differences in left hemisphere activation. Second, we found that healthy subjects who have relatively high left lateralization in the angular gyrus also have relatively low left lateralization in the ventral precentral gyrus. These findings illustrate spatial heterogeneity in language lateralization that is lost when global laterality measures are considered. It is likely that the complex spatial variability we observed in healthy controls is more exaggerated in patients with brain damage. We therefore highlight the importance of investigating within hemisphere regional variations in fMRI activation, prior to neuro-surgical intervention, to determine how each hemisphere and each region contributes to language processing. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc.

Influence of deep sternal wound infection on long-term survival after cardiac surgery.

BACKGROUND: This study aimed to investigate the influence of deep sternal wound infection on long-term survival following cardiac surgery. MATERIAL AND METHODS: In our institutional database we retrospectively evaluated medical records of 4732 adult patients who received open-heart surgery from January 1995 through December 2005. The predictive factors for DSWI were determined using logistic regression analysis. Then, each patient with deep sternal wound infection (DSWI) was matched with 2 controls without DSWI, according to the risk factors identified previously. After checking balance resulting from matching, short-term mortality was compared between groups using a paired test, and long-term survival was compared using Kaplan-Meier analysis and a Cox proportional hazard model. RESULTS: Overall, 4732 records were analyzed. The mean age of the investigated population was 69.3±12.8 years. DSWI occurred in 74 (1.56%) patients. Significant independent predictive factors for deep sternal infections were active smoking (OR 2.19, CI95 1.35-3.53, p=0.001), obesity (OR 1.96, CI95 1.20-3.21, p=0.007), and insulin-dependent diabetes mellitus (OR 2.09, CI95 1.05-10.06, p=0.016). Mean follow-up in the matched set was 125 months, IQR 99-162. After matching, in-hospital mortality was higher in the DSWI group (8.1% vs. 2.7% p=0.03), but DSWI was not an independent predictor of long-term survival (adjusted HR 1.5, CI95 0.7-3.2, p=0.33). CONCLUSIONS: The results presented in this report clearly show that post-sternotomy deep wound infection does not influence long-term survival in an adult general cardio-surgical patient population.

Imputation in data fusion of heterogeneous data sets a model-based numerical experiment

Given the very large amount of data obtained everyday through population surveys, much of the new research again could use this information instead of collecting new samples. Unfortunately, relevant data are often disseminated into different files obtained through different sampling designs. Data fusion is a set of methods used to combine information from different sources into a single dataset. In this article, we are interested in a specific problem: the fusion of two data files, one of which being quite small. We propose a model-based procedure combining a logistic regression with an Expectation-Maximization algorithm. Results show that despite the lack of data, this procedure can perform better than standard matching procedures.

Die loutrophóros im Hochzeits-und Begräbnisritual des 5. Jahrhunderts v. Chr. in Athen

ZUSAMMENFASSUNG Gegenstand dieser Arbeit sind rund hundert rotfigurige Darstellungen von den beiden als Lutrophoren bezeichneten Tongefässen, der dreihenkligen Lutrophoros-Hydria (LH) und der zweihenkligen Lutrophoros-Amphora (LA). Die Untersuchung geht von der Prämisse aus, dass Darstellungen der Lutrophoros einen gewissen Variantenreichtum des Brauchtums widerspiegeln können, sonst aber verbindlichen, in sich schlüssigen Vorstellungen entsprechen, die sich die Gemeinschaft von diesem Ritualobjekt macht. In Anlehnung an die herrschende Meinung wird zudem vorausgesetzt, dass LA und LH ausschliesslich im nuptialen und funeralen Bereich vorkommen, doch ist bisher in der archäologischen Forschung ihre Rolle im einzelnen ungeldärt. Anhand von literarischen Quellen und ikonographischem Material wird untersucht, inwiefern sich LA und LH in ihrer Verwendung und Bedeutung in bezug auf Hochzeit und Begräbnis unterscheiden und inwieweit der Begrifif loutrophóros auf sie zutrifft. KAPITEL I Nach frühen Quellentexten muss die Bezeichnung loutrophóros im Hochzeitsritual für eine Person und beim Begräbnis eines ehelos verstorbenen Mannes für ein Objekt verwendet worden sein. In späteren Zeugnissen wird ergänzend die Lutrophoros für die Hochzeit als hydria-ähnliches Gefäss bezeichnet, ebenso die Lutrophoros auf dem Grab; für letztere wird zusätzlich eine Kinderfigur mit Wassergefäss vorgeschlagen, was archäologisch bislang nicht bezeugt ist. Die Aussagen der Texte zum Begriff loutrophóros stimmen trotz verschiedener Widersprüche im Gesamten darin überein, dass die Aufstellung der Lutrophoros auf dem Grab von ehelos Verstorbenen eine Entsprechung zum Ritual für Hochzeitsleute darstellt; die rituelle Verwendung der Lutrophoros auf dem Grab muss also eine nuptiale Bedeutung haben. Die Untersuchung des Begriffs loutrá (,,Hoch- zeitsba") im nuptialen Bereich zeigt, dass die Lutrophoros in engem Zusammenhang mit der Quellnymphe Kallirrhoë, der Braut - nýmphè genannt - und dem Heiligtum der Nymphe, dem Hauptfundort der Lutrophoren, gesehen werden muss; allerdings bleibt die spezifische Bedeutung der loutrá ungewiss. Am ehesten werden sie dem Gedeihen der neu entstandenen Verbindung gedient haben, die sich in Anlehnung an Hesiods Werke und Tage als Neugründung eines oíkos oder als Weiteiterführung des väterlichen oíkos durch den Bräutigam umschreiben lässt. Für die bislang immer wieder vorgeschlagenen Deutungen der loutrá als Ritual für Fruchtbarkeit oder zur Reinigung gibt es frühestens ab dem 4. ]h. v. Chr. Hinweise. Die Untersuchung des Begriffs loutrá für die Waschung vor der Bestattung und ein Vergleich zwischen verschiedenen Bezeichnungen für Grab- spenden (choaí, loibaí, loutrá) und der aufgestellten Lutrophoros auf dem Grab führen entgegen bisheriger Auffassungen zum Schluss, dass die Lutrophoros auf dem Grab als Entsprechung zum Hochzeitsritual gesehen wurde und dass diesem Brauch die für Athen bekannte Vorstellung zugrunde liegt, die Verstorbenen zufrieden zu stellen. Die aufgestellte Lutrophoros könnte zum Ausdruck bringen, dass die Hinterbliebenen das der verstorbenen Person zustehende Recht auf Verehelichung gebilligt hätten. Kapitel II Beim ikonographischen Material, das sich hauptsächlich aus Vasenbildern zusammensetzt, stehen die dargestellten Gefässvarianten LA und LH im Zentrum. Nach dem ikonographischen Modell von C. Bérard fassen wir die dargestellten LA und LH im linguistischen Sinn als ikonische Zeichen auf, die nicht weiter zerlegbar sind; LA und LH stellen je eine ,,unité formelle minimale " dar. Die zentrale Frage lautet, ob Bedeutung und Verwendung der beiden ,,unités formelles minimales" LH und LA - trotz ihrer unterschiedlichen Form -in bezug auf die Funktion der loutrophóros bei der Hochzeit und beim Begräbnis ehelos Verstorbener übereinstimmen oder ob die unterschiedliche Form von LA und LH zum Ausdruck bringen soll, dass sie eben gerade nicht die gleiche Funktion haben. Beide Auffassungen sind in der bisherigen Forschung stark vertreten: R Wolters und seine Anhänger gehen davon aus, dass LA und LH gleichwertig sind; G. Kokula und mit ihr andere nehmen eine unterschiedliche, geschlechtsspezifische Verwendung an. In einer ersten formalen Analyse werden Darstellungen von LA und LH auf Lutrophoren, Lebetes gamikoi und Hydrien untersucht. Folgende Skizze zeigt die bekannten Kombinationen von dargestellten Lutrophoren: Aus der formalen Analyse lassen sich vier Schlüsse ziehen: - (ia.b) In der Regel entsprechen sich Bildträger und Bildelement; dieser Kombination muss eine Absicht zugrunde liegen, sie kann nicht willkürlich sein. - (2) Zwei LA mit Darstellungen einer LH (49 Abb. 4oa.b; 50 Abb. 4ia.b) sprechen dafür, dass im Verwendungsbereich der LA auch die LH vorkommen kann; im Gegensatz dazu fehlen aber Darstellungen einer LA auf einer LH, was vermuten lässt, dass im Verwendungsbereich der LH keine LA gebraucht wurden. - (3a.b) Zwei Darstellungen zeigen jede Variante für sich in zwei Exemplaren in der Funktion als Wasserbehälter: zwei LH (I7 Abb. 61b.c; 6za. b); zwei LA (12 Abb. 46. 47a.b); im Gegensatz dazu kommen aber beide Varianten gemeinsam in der Funktion als Wasserbehälter nicht vor, vermutlich hat sich der Anwendungsbereich der beiden Varianten unterschieden. (4a.b) Zwei Darstellungen, die beide Varianten gemeinsam zeigen, einmal im Miniaturformat (50 Abb. 41a.b), das andere Mai in monumentaler Grösse (I Abb. 1) - also nicht als Wasserbehälter -, lassen den Schluss zu, dass beide Varianten ein gemeinsames Merkmal haben müssen. Allein die formale Analyse zeigt, dass die von P Wolters angenommene Gleichwertigkeit nicht zutreffen kann. Es muss eine unterschiedliche Verwendung gegeben haben, wie bereits G. Kokula vermutet. In einer zweiten Analyse werden die Darstellungen nach der von P Bruneau vorgeschlagenen Methode in fünf Gruppen mit gleichem Schema aufgelisret. Hier wird die dargestellte LA oder LH im Vergleich zur Gesamtdarstellung ausgewertet, ohne die inhaltliche Klassifizierung vorauszusetzen. In einer Gruppe gesondert werden alle Lutrophorendarstellungen untersucht, die thematisch eindeutig zum funeralen Bereich gehören. Die aus der ersten Analyse gewonnene Annahme, dass sich LA und LH in der Verwendung unterscheiden, wird durch die zweite Analyse bestätigt und präzisiert. Für die LA kann keine eindeutige hochzeitliche Verwendung nachgewiesen werden; die LH ist das eigentliche Hochzeitsgefäss. Darüber hinaus zeigt die Untersuchung, dass alle Darstellungen einer LH oder LA inhaltlich dem nuptialen oder funeralen Kontext zugeordnet werden können; gemäss den Darstellungen wurden LA und LH nur bei Hochzeit oder Begräbnis verwendet. Nach dem hier vorgestellten Modell machen LA und LH als ikonische Zeichen eine doppelte Aussage. Sie verweisen einerseits auf den Inhalt, das hochzeitliche Wasser, und darin sind sie bedeutungsgleich. Andererseits beziehen sie sich auf die Adressaten: die LA kommt für Hochzeitsleute nicht in Frage, ihre Verwendung ist auf ehelos Verstorbene beschränkt. Die LH, das Ritualobjekt der Hochzeitsleute, kann vereinzelt auch für Verstorbene gebraucht werden. Diese zunächst irritierende Beobachtung stimmt mit den Texten gut überein, aus denen hervorgeht, dass im Ritual für ehelos Verstorbene eine Entsprechung zum Hochzeitsritual liegt; seine Bedeutung muss daher ebenfalls nuptial sein. Die Kombination von hochzeitlichen und funeralen Elementen ist daher nach dem hier vorgeschlagenen Modell im Funeralbereich - und zwar nur dort - möglich. Ebenfalls in Übereinstimmung mit den Texten lassen sich die beiden Darstellungen erklären, die LA und LH gemeinsam im Miniaturformat oder in monumentaler Grösse zeigen. Da nämlich die Mitgabe der Lutrophoros für ehelos Verstorbene auf die hochzeitlichen loutrá verweist, haben beide Gefässvarianten trotz der unterschiedlichen Verwendung eine gleichwertige Bedeutung, und daraus erklärt sich die gemeinsame Darstellung beider Varianten in einem Format, das die rituelle Verwendung ausschliesst. Durch die zweíte Analyse wird die Auffassung der geschlechtsspezifischen Verwendung von G. Kokula entkräftet. LA und LH unterscheiden sich zwar in der Verwendung, diese ist jedoch entgegen bisheriger Annahmen nicht symmetrisch. KAPITEL III Der Vergleich zwischen literarischer und ikonographischer Überlieferung zeigt einerseits das bekannte Problem, dass beide Bildelemente LA und LH nicht zweifelsfrei dem Begriff loutrophóros zugewiesen werden können. Andererseits aber stimmen Bilder und Texte in bezug auf die rituelle Funktion der loutrophóros bei Hochzeit und Begräbnis in einem hohen Mass überein, so dass widersprüchliche Aussagen nicht mehr so stark ins Gewicht fallen wie bislang. Die von einigen Lexikographen - entgegen der íkonographisch dokumentierten LA - vorgeschlagene Kinderstatue als loutrophóros auf dem Grab ehelos Verstorbener beruht vermutlich auf der Auffassung, dass sich das Erscheinungsbild der loutrophóros als Person beziehungsweise Gestalt im Hochzeíts- und Begräbnisritual entspreche. Bei dieser erst in späterer Zeit auftretenden Meinung wird deutlich, dass der ursprünglich adjektivischen Verwendung von loutrophóros, gemäss welcher bei Hochzeit und Begräbnis völlig verschiedene Wasserträger möglich sind, nicht mehr Rechnung getragen wird. KAPITEL IV Die aus den literarischen Quellen und der ikonographischen Überlieferung gezogenen Schlussfolgerungen können auch gegenüber weiteren archäologischen Gesichtspunkten, wie Gefässentwieklung und Fundorte, aufrecht erhalten bleiben. Damit würde das hier vertretene Modell unserer Forderung Rechnung tragen, dass die mit einem Ritualobjekt (hier LH und LA) verbundenen Vorstellungen kohärent sein müssen, aber eine gewisse Bandbreite von rituellen Ausführungsmodalitäten zulassen.

CATMA, a comprehensive genome-scale resource for silencing and transcript profiling of Arabidopsis genes.

BACKGROUND: The Complete Arabidopsis Transcript MicroArray (CATMA) initiative combines the efforts of laboratories in eight European countries 1 to deliver gene-specific sequence tags (GSTs) for the Arabidopsis research community. The CATMA initiative offers the power and flexibility to regularly update the GST collection according to evolving knowledge about the gene repertoire. These GST amplicons can easily be reamplified and shared, subsets can be picked at will to print dedicated arrays, and the GSTs can be cloned and used for other functional studies. This ongoing initiative has already produced approximately 24,000 GSTs that have been made publicly available for spotted microarray printing and RNA interference. RESULTS: GSTs from the CATMA version 2 repertoire (CATMAv2, created in 2002) were mapped onto the gene models from two independent Arabidopsis nuclear genome annotation efforts, TIGR5 and PSB-EuGène, to consolidate a list of genes that were targeted by previously designed CATMA tags. A total of 9,027 gene models were not tagged by any amplified CATMAv2 GST, and 2,533 amplified GSTs were no longer predicted to tag an updated gene model. To validate the efficacy of GST mapping criteria and design rules, the predicted and experimentally observed hybridization characteristics associated to GST features were correlated in transcript profiling datasets obtained with the CATMAv2 microarray, confirming the reliability of this platform. To complete the CATMA repertoire, all 9,027 gene models for which no GST had yet been designed were processed with an adjusted version of the Specific Primer and Amplicon Design Software (SPADS). A total of 5,756 novel GSTs were designed and amplified by PCR from genomic DNA. Together with the pre-existing GST collection, this new addition constitutes the CATMAv3 repertoire. It comprises 30,343 unique amplified sequences that tag 24,202 and 23,009 protein-encoding nuclear gene models in the TAIR6 and EuGène genome annotations, respectively. To cover the remaining untagged genes, we identified 543 additional GSTs using less stringent design criteria and designed 990 sequence tags matching multiple members of gene families (Gene Family Tags or GFTs) to cover any remaining untagged genes. These latter 1,533 features constitute the CATMAv4 addition. CONCLUSION: To update the CATMA GST repertoire, we designed 7,289 additional sequence tags, bringing the total number of tagged TAIR6-annotated Arabidopsis nuclear protein-coding genes to 26,173. This resource is used both for the production of spotted microarrays and the large-scale cloning of hairpin RNA silencing vectors. All information about the resulting updated CATMA repertoire is available through the CATMA database http://www.catma.org.

Oscillation modes of microtubules.

Microtubules are long, filamentous protein complexes which play a central role in several cellular physiological processes, such as cell division transport and locomotion. Their mechanical properties are extremely important since they determine the biological function. In a recently published experiment [Phys. Rev. Lett. 89 (2002) 248101], microtubule's Young's and shear moduli were simultaneously measured, proving that they are highly anisotropic. Together with the known structure, this finding opens the way to better understand and predict their mechanical behavior under a particular set of conditions. In the present study, we modeled microtubules by using the finite elements method and analyzed their oscillation modes. The analysis revealed that oscillation modes involving a change in the diameter of the microtubules strongly depend on the shear modulus. In these modes, the correlation times of the movements are just slightly shorter than diffusion times of free molecules surrounding the microtubule. It could be therefore speculated that the matching of the two timescales could play a role in facilitating the interactions between microtubules and MT associated proteins, and between microtubules and tubulins themselves.

Assessment of Epstein-Barr virus nucleic acids in gastric but not in breast cancer by next-generation sequencing of pooled Mexican samples

Gastric (GC) and breast (BrC) cancer are two of the most common and deadly tumours. Different lines of evidence suggest a possible causative role of viral infections for both GC and BrC. Wide genome sequencing (WGS) technologies allow searching for viral agents in tissues of patients with cancer. These technologies have already contributed to establish virus-cancer associations as well as to discovery new tumour viruses. The objective of this study was to document possible associations of viral infection with GC and BrC in Mexican patients. In order to gain idea about cost effective conditions of experimental sequencing, we first carried out an in silico simulation of WGS. The next-generation-platform IlluminaGallx was then used to sequence GC and BrC tumour samples. While we did not find viral sequences in tissues from BrC patients, multiple reads matching Epstein-Barr virus (EBV) sequences were found in GC tissues. An end-point polymerase chain reaction confirmed an enrichment of EBV sequences in one of the GC samples sequenced, validating the next-generation sequencing-bioinformatics pipeline.

Impact of inadequate empirical therapy on the mortality of patients with bloodstream infections: a propensity score-based analysis.

The impact of the adequacy of empirical therapy on outcome for patients with bloodstream infections (BSI) is key for determining whether adequate empirical coverage should be prioritized over other, more conservative approaches. Recent systematic reviews outlined the need for new studies in the field, using improved methodologies. We assessed the impact of inadequate empirical treatment on the mortality of patients with BSI in the present-day context, incorporating recent methodological recommendations. A prospective multicenter cohort including all BSI episodes in adult patients was performed in 15 hospitals in Andalucía, Spain, over a 2-month period in 2006 to 2007. The main outcome variables were 14- and 30-day mortality. Adjusted analyses were performed by multivariate analysis and propensity score-based matching. Eight hundred one episodes were included. Inadequate empirical therapy was administered in 199 (24.8%) episodes; mortality at days 14 and 30 was 18.55% and 22.6%, respectively. After controlling for age, Charlson index, Pitt score, neutropenia, source, etiology, and presentation with severe sepsis or shock, inadequate empirical treatment was associated with increased mortality at days 14 and 30 (odds ratios [ORs], 2.12 and 1.56; 95% confidence intervals [95% CI], 1.34 to 3.34 and 1.01 to 2.40, respectively). The adjusted ORs after a propensity score-based matched analysis were 3.03 and 1.70 (95% CI, 1.60 to 5.74 and 0.98 to 2.98, respectively). In conclusion, inadequate empirical therapy is independently associated with increased mortality in patients with BSI. Programs to improve the quality of empirical therapy in patients with suspicion of BSI and optimization of definitive therapy should be implemented.

Positioning an underwater vehicle through image mosaicking

Mosaics have been commonly used as visual maps for undersea exploration and navigation. The position and orientation of an underwater vehicle can be calculated by integrating the apparent motion of the images which form the mosaic. A feature-based mosaicking method is proposed in this paper. The creation of the mosaic is accomplished in four stages: feature selection and matching, detection of points describing the dominant motion, homography computation and mosaic construction. In this work we demonstrate that the use of color and textures as discriminative properties of the image can improve, to a large extent, the accuracy of the constructed mosaic. The system is able to provide 3D metric information concerning the vehicle motion using the knowledge of the intrinsic parameters of the camera while integrating the measurements of an ultrasonic sensor. The experimental results of real images have been tested on the GARBI underwater vehicle

Advances in Sequence Analysis: Theory, Methods, Applications

This book gives a general view of sequence analysis, the statistical study of successions of states or events. It includes innovative contributions on life course studies, transitions into and out of employment, contemporaneous and historical careers, and political trajectories. The approach presented in this book is now central to the life-course perspective and the study of social processes more generally. This volume promotes the dialogue between approaches to sequence analysis that developed separately, within traditions contrasted in space and disciplines. It includes the latest developments in sequential concepts, coding, atypical datasets and time patterns, optimal matching and alternative algorithms, survey optimization, and visualization. Field studies include original sequential material related to parenting in 19th-century Belgium, higher education and work in Finland and Italy, family formation before and after German reunification, French Jews persecuted in occupied France, long-term trends in electoral participation, and regime democratization. Overall the book reassesses the classical uses of sequences and it promotes new ways of collecting, formatting, representing and processing them. The introduction provides basic sequential concepts and tools, as well as a history of the method. Chapters are presented in a way that is both accessible to the beginner and informative to the expert.

Modelling short-term ultraviolet exposure as an alternative to individual dosimetry

Background: Excessive exposure to solar Ultra-Violet (UV) light is the main cause of most skin cancers in humans. Factors such as the increase of solar irradiation at ground level (anthropic pollution), the rise in standard of living (vacation in sunny areas), and (mostly) the development of outdoor activities have contributed to increase exposure. Thus, unsurprisingly, incidence of skin cancers has increased over the last decades more than that of any other cancer. Melanoma is the most lethal cutaneous cancer, while cutaneous carcinomas are the most common cancer type worldwide. UV exposure depends on environmental as well as individual factors related to activity. The influence of individual factors on exposure among building workers was investigated in a previous study. Posture and orientation were found to account for at least 38% of the total variance of relative individual exposure. A high variance of short-term exposure was observed between different body locations, indicating the occurrence of intense, subacute exposures. It was also found that effective short-term exposure ranged between 0 and 200% of ambient irradiation, suggesting that ambient irradiation is a poor predictor of effective exposure. Various dosimetric techniques enable to assess individual effective exposure, but dosimetric measurements remain tedious and tend to be situation-specific. As a matter of facts, individual factors (exposure time, body posture and orientation in the sun) often limit the extrapolation of exposure results to similar activities conducted in other conditions. Objective: The research presented in this paper aims at developing and validating a predictive tool of effective individual exposure to solar UV. Methods: Existing computer graphic techniques (3D rendering) were adapted to reflect solar exposure conditions and calculate short-term anatomical doses. A numerical model, represented as a 3D triangular mesh, is used to represent the exposed body. The amount of solar energy received by each "triangle is calculated, taking into account irradiation intensity, incidence angle and possible shadowing from other body parts. The model take into account the three components of the solar irradiation (direct, diffuse and albedo) as well as the orientation and posture of the body. Field measurements were carried out using a forensic mannequin at the Payerne MeteoSwiss station. Short-term dosimetric measurements were performed in 7 anatomical locations for 5 body postures. Field results were compared to the model prediction obtained from the numerical model. Results: The best match between prediction and measurements was obtained for upper body parts such as shoulders (Ratio Modelled/Measured; Mean = 1.21, SD = 0.34) and neck (Mean = 0.81, SD = 0.32). Small curved body parts such as forehead (Mean = 6.48, SD = 9.61) exhibited a lower matching. The prediction is less accurate for complex postures such as kneeling (Mean = 4.13, SD = 8.38) compared to standing up (Mean = 0.85, SD = 0.48). The values obtained from the dosimeters and the ones computed from the model are globally consistent. Conclusion: Although further development and validation are required, these results suggest that effective exposure could be predicted for a given activity (work or leisure) in various ambient irradiation conditions. Using a generic modelling approach is of high interest in terms of implementation costs as well as predictive and retrospective capabilities.

Analytical expressions for the flame front speed in the downward combustion of thin solid fuels and comparison to experiments

We derive analytical expressions for the propagation speed of downward combustion fronts of thin solid fuels with a background flow initially at rest. The classical combustion model for thin solid fuels that consists of five coupled reaction-convection-diffusion equations is here reduced into a single equation with the gas temperature as the single variable. For doing so we apply a two-zone combustion model that divides the system into a preheating region and a pyrolyzing region. The speed of the combustion front is obtained after matching the temperature and its derivative at the location that separates both regions.We also derive a simplified version of this analytical expression expected to be valid for a wide range of cases. Flame front velocities predicted by our analyticalexpressions agree well with experimental data found in the literature for a large variety of cases and substantially improve the results obtained from a previous well-known analytical expression

What Was I Thinking? Eye-Tracking Experiments Underscore the Bias that Architecture Exerts on Nuclear Grading in Prostate Cancer.

We previously reported that nuclear grade assignment of prostate carcinomas is subject to a cognitive bias induced by the tumor architecture. Here, we asked whether this bias is mediated by the non-conscious selection of nuclei that "match the expectation" induced by the inadvertent glance at the tumor architecture. 20 pathologists were asked to grade nuclei in high power fields of 20 prostate carcinomas displayed on a computer screen. Unknown to the pathologists, each carcinoma was shown twice, once before a background of a low grade, tubule-rich carcinoma and once before the background of a high grade, solid carcinoma. Eye tracking allowed to identify which nuclei the pathologists fixated during the 8 second projection period. For all 20 pathologists, nuclear grade assignment was significantly biased by tumor architecture. Pathologists tended to fixate on bigger, darker, and more irregular nuclei when those were projected before kigh grade, solid carcinomas than before low grade, tubule-rich carcinomas (and vice versa). However, the morphometric differences of the selected nuclei accounted for only 11% of the architecture-induced bias, suggesting that it can only to a small part be explained by the unconscious fixation on nuclei that "match the expectation". In conclusion, selection of « matching nuclei » represents an unconscious effort to vindicate the gravitation of nuclear grades towards the tumor architecture.

Proteomic analysis of mononuclear cells of patients with minimal-change nephrotic syndrome of childhood.

Background/Aims. Recently, peripheral blood mononuclear cell transcriptome analysis has identified genes that are upregulated in relapsing minimal-change nephrotic syndrome (MCNS). In order to investigate protein expression in peripheral blood mononuclear cells (PBMC) from relapsing MCNS patients, we performed proteomic comparisons of PBMC from patients with MCNS in relapse and controls. METHODS: PBMC from a total of 20 patients were analysed. PBMC were taken from five patients with relapsing MCNS, four in remission, five patients with other glomerular diseases and six controls. Two dimensional electrophoresis was performed and proteome patterns were compared. RESULTS: Automatic heuristic clustering analysis allowed us to pool correctly the gels from the MCNS patients in the relapse and in the control groups. Using hierarchical population matching, nine spots were found to be increased in PBMC from MCNS patients in relapse. Four spots were identified by mass spectrometry. Three of the four proteins identified (L-plastin, alpha-tropomyosin and annexin III) were cytoskeletal-associated proteins. Using western blot and immunochemistry, L-plastin and alpha-tropomyosin 3 concentrations were found to be enhanced in PBMC from MCNS patients in relapse. Conclusions. These data indicate that a specific proteomic profile characterizes PBMC from MCNS patients in relapse. Proteins involved in PBMC cytoskeletal rearrangement are increased in relapsing MCNS. We hypothesize that T-cell cytoskeletal rearrangement may play a role in the pathogenesis of MCNS by altering the expression of cell surface receptors and by modifying the interaction of these cells with glomerular cells.

Impact of social structure variation on population genetics, social conflicts and life histories in ants

Summary The evolution of social structures and breeding systems in animals is a complex process that combines ecological, genetical and social factors. This thesis sheds light on important changes in population genetics, life-history and social behavior that are associated with variation in social structure in ants. The socially polymorphic ant Formica selysi was chosen as the model organism because single- and multiple-queen colonies occur in close proximity within a single large population. The shift from single- to multiple-queen colonies is generally associated with profound changes in dispersal behavior and mode of colony founding. In chapter 1, we examine the genetic consequences of variation in social structure at both the colony and population levels. A detailed microsatellite analysis reveals that both colony types have similar mating systems, with few or no queen turnover. Furthermore, the complete lack of genetic differentiation observed between single- and multiple-queen colonies provides no support to the hypothesis that change in queen number leads to restricted gene flow between social forms. Besides changes in the genetic composition of the colony, the variation in the number of queens per colony is associated with changes in a network of behavioral and life-history traits that have been described as forming a "polygyny syndrome". In chapter 2, we demonstrate that multiple-queen colonies profoundly differ from single-queen ones in terms of size, nest density and lifespan of colonies, in weight of queens produced, as well as in allocation to reproductive individuals relative to workers. These multifaceted changes in life-history traits can provide various fitness benefits to members of multiple-queen colonies. Increasing the number of queens in a colony usually results in a decreased level of aggression towards non-nestmates. The phenotype matching hypothesis predicts that, compared to single-queen colonies, multiple-queen colonies have more diverse genetically-derived cues used for recognition, resulting in a lower ability to discriminate non-nestmates. In sharp contrast to this hypothesis, we show in chapter 3 that single- and multiple-queen colonies exhibit on average similar levels of aggression. Moreover, stronger aggression is recorded between colonies of different social structure than between colonies of the same social structure. Several hypotheses propose that the evolution of multiple-queen colonies is at least partly due to benefits resulting from an increase in colony genetic diversity. The task-efficiency hypothesis holds that genetic variation improves task performance due to a more complete or more sensitive expression of the genetically-based division of labor. In .chapter 4, we evaluate if higher colony genetic diversity increases worker size polymorphism and thus may improve division of labor. We show that despite the fact that worker size has a heritable component, higher levels of genetic diversity do not result in more polymorphic workers. The smaller size and lower polymorphism levels of workers of multiple-queen colonies compared to single-queen ones further indicate that an increase in colony genetic diversity does not increase worker size polymorphism but might improve colony homeostasis. In chapter 5, we provide clear evidence for an ongoing conflict between queens and workers on sex allocation, as predicted by kin selection theory. Our data show that queens of F. selysi strongly influence colony sex allocation by biasing the sex ratio of their eggs. However, there is also evidence that workers eliminated some male brood, resulting in a population sex-investment ratio that is between the queens' and workers' equilibria. Résumé L'évolution des structures sociales et systèmes d'accouplement chez les animaux est un processus complexe combinant à la fois des facteurs écologiques, génétiques et sociaux. Cette thèse met en lumière des changements importants dans la génétique des populations, les traits d'histoire de vie et les comportements sociaux qui sont associés à des variations de structure sociale chez les fourmis. Durant ce travail, nous avons étudié une population de Formica selysi composée à la fois de colonies à une reine et de colonies à plusieurs reines. La transition de colonie à une reine à colonie à plusieurs reines est généralement associée à des changements profonds dans le comportement de dispersion ainsi que le mode de fondation des sociétés. Dans le chapitre 1, nous examinons les conséquences génétiques de la variation de structure sociale tant au niveau de la colonie qu'au niveau de la population. Une analyse détaillée à l'aide de marqueurs microsatellites nous révèle que les deux types de colonies ont des systèmes d'accouplements similaires avec peu ou pas de renouvellement de reines. L'absence totale de différenciation génétique entre les colonies à une et à plusieurs reines n'apporte aucun support à l'hypothèse selon laquelle un changement dans le nombre de reines conduit à un flux de gènes restreint entre les deux formes sociales. A côté de changements dans la composition génétique de la colonie, la variation du nombre de reines dans une colonie est associée à une multitude de changements comportementaux et de traits d'histoire de vie qui ont été décrits comme formant un "syndrome polygyne". Dans le chapitre 2, nous démontrons que les colonies à plusieurs reines diffèrent profondément des colonies à une reine en terme de taille, densité de nids, longévité des colonies, poids des nouvelles reines produites ainsi que dans l'allocation entre les individus reproducteurs et les ouvrières. Ces changements multiples dans les traits d'histoire de vie peuvent apporter des bénéfices variés en terme de fitness aux colonies à plusieurs reines. L'augmentation du nombre de reines dans une colonie est généralement associée à une baisse du degré d'agressivité envers les fourmis étrangères au nid. L'hypothèse "phénotype matching" prédit que les colonies à plusieurs reines ont une plus grande diversité dans les facteurs d'origine génétique utilisés pour la reconnaissance, résultant en une capacité diminuée à discriminer une fourmi étrangère au nid. Contrairement à cette hypothèse, nous montrons dans le chapitre 3 que les colonies à une et à plusieurs reines ont des niveaux d'agressivité similaires. De plus, une agressivité accrue est observée entre colonies de structures sociales différentes comparée à des colonies de même structure sociale. Plusieurs hypothèses ont proposé que l'évolution de colonies ä plusieurs reines soit en partie due aux bénéfices résultant d'une augmentation de la diversité génétique dans la colonie. L'hypothèse "task efficiency" prédit que la diversité génétique améliore l'efficacité à effectuer certaines tâches grâce à une expression plus complète et plus souple d'une division du travail génétiquement déterminée. Nous évaluons dans le chapitre 4 si un accroissement de la diversité génétique augmente le polymorphisme de taille des ouvrières, d'où peut ainsi découler une meilleure division du travail. Nous montrons qu'en dépit du fait que la taille des ouvrières soit un caractère héritable, une forte diversité génétique ne se traduit pas par un plus fort polymorphisme chez les ouvrières. Les ouvrières de colonies à plusieurs reines sont plus petites et moins polymorphes que celles des colonies à une seule reine. Dans le chapitre 5, nous démontrons l'existence d'un conflit ouvert entre reines et ouvrières à propos de l'allocation dans les sexes, comme le prédit la théorie de la sélection de parentèle. Nos données révèlent que les reines de F. selysi influencent fortement l'allocation dans les sexes en biaisant la sexe ratio des oeufs. Cependant, certains indices indiquent que les ouvrières éliminent une partie du couvain mâle, ce qui a pour effet d'avoir un investissement dans les sexes au niveau de la population intermédiaire entre les intérêts des reines et des ouvrières.