Relaxations of the Maximum Flow Minimum Cut Property for Ideal Clutters

Given a family of sets, a covering problem consists of finding a minimum cost collection of elements that hits every set. This objective can always be bound by the maximum number of disjoint sets in the family, we refer to this as the covering dual, since when we allow covers to be fractional and relax the notion of disjoint sets, the natural Linear Programming (LP) formulations become duals and the optimal objective values of the two LPs match. A consequence of the Edmonds-Giles theorem about Totally Dual Integral systems is that if we assume the covering dual always has an optimal integer solution for every cost function, then we can always find an optimal integer cover. The converse does not hold in general, but a still standing conjecture from the mid-1970s states that the existence of an optimal integer cover for every cost function implies the existence of a 1/4-integer optimal solution to the dual for every cost function. In this thesis we discuss weaker versions of the conjecture and build tools allowing us to approach them

The Indirect Effects of New Housing Construction in Developing Countries

Summary . The aim of this paper is to examine the indirect effects of new housing construction on the redistribution of old housing stock in developing countries. The basic data for the study comes from the author's work in Tunisia, with comparative illustration from similar studies in Mexico, and is used to test a certain number of conclusions on filtering derived from empirical studies undertaken in developed countries. The conclusions are that dwellings in the middle range of values initiated the longest chains of moves, but that as even these chains end before reaching the poorest families, filtering strategies need to be complemented by a positive programme of slum-upgrading

Adenomyose utérine, étude clinique et thérapeutique: à propos de 87 cas

Le but de notre étude est l'analyse des différents aspects épidémiologiques, cliniques, paracliniques et thérapeutiques de l'adénomyose. Il s'agit d'une étude rétrospective sur 87 patientes ayant bénéficié d'une hystérectomie pour des raisons diverses (hors prolapsus) entre le 1er janvier 2000 et 31 décembre 2006 et dont l'étude histologique de la pièce opératoire a révélé la présence d'adénomyose. 586 hystérectomies (hors prolapsus) ont été réalisées pendant la même période d'étude, soit une fréquence de l'adénomyose sur pièce opératoire de 14.85%. L'age moyen de nos patientes est de 43.97 ans (extrêmes: 26-64 ans). 29.88% d'entres-elles sont ménopausées et 41.37% avaient des antécédents de traumatisme utérin. La  symptomatologie a été dominée par les ménometrorragies (82.77%) et les douleurs pelviennes  (71.22%). Le diagnostic préopératoire a été suspecté sur les données de l'hystéroscopie dans 63.22% des cas, de  l'hystérographie dans 58.46% des cas et de l'échographie transvaginale dans 40.5% des cas. Une chirurgie  radicale a été indiquée de première intention dans 57 cas, après échec du traitement  médical dans 16 cas et après échec d'une réduction endométriale dans 14 cas. L'analyse histologique des pièces d'hystérectomie  trouve des myomes associés dans 32.18% des cas, une hyperplasie de  l'endomètre dans 13.79%, des  polypes dans 5.74% et une atrophie de l'endomètre dans 3.44%. L'adénomyose, maladie énigmatique,  échappe toujours à une stratégie thérapeutique bien codifiée, et demeure étroitement liée à l'hystérectomie. Son dépistage chez des femmes de plus en plus jeunes et à des stades moins avancés pourrait éviter  l'évolution systématique vers les traitements radicaux.Key words: Adénomyose, métrorragies, hystérectomi

Fossa Regia

Comme toutes les questions de frontière, le problème de la Fossa Regia est loin de se limiter au simple tracé d’une ligne de démarcation entre deux pays ou deux provinces. En fait, il touche à des aspects les plus divers, tels que la politique menée par les protagonistes de l’époque, – que ce soit les rois numides ou Rome, – les opérations militaires, les institutions municipales et juridiques, la pertica de la colonie de Carthage, le droit des gens et du sol, l’assiette foncière, la répartit..

Cardage

Le cardage est un traitement indispensable de la laine qui précède le filage. Il existe aussi une autre forme de cardage, celle qui s’applique aux chéchias avant leur teinture. Les instruments nécessaires à ces traitements ne sont pas les mêmes. Mais dans un cas comme dans l’autre il s’agit d’opérations liées à des artisanats disparus ou en perdition. Le cardage de la laine Le cardage de la laine est une opération qui se place entre le lavage de la toison et le filage de la laine. Comme l’écr..

The Association Between French Veterinary Practice Characteristics and Their Revenues and Veterinarian's Time Use

The provision of healthcare by veterinarians consists of a blend of activities ensuring welfare for animals. It also contributes in the control of infectious diseases and food safety. In general practices, most of the activities generate incomes for veterinarians, notably acts (consultations, surgery, etc.) and sales (drugs, pet food, etc.). Increased size of veterinary practices and the arrival of corporate companies modify the veterinary landscape in many countries. In a context of rapid growth of the companion animal health market, the question of the profitability of veterinary activities is relevant. Indeed, beyond a certain threshold, veterinarians may be tempted to leave behind food-producing animals' acts and focus on companion animals' acts, which are generally recognized to be more profitable and more attractive for new generations of veterinarians. A survey was conducted in French veterinary mixed practices, and a regression analysis was used to quantify the relationships between the turnover and the characteristics of veterinary practices, the time to perform veterinary acts, and the characteristics of veterinarians. We found that the characteristics of veterinary practices are positively associated with the turnover and the price of acts, and that there was an association between the status of veterinarians (associate, collaborator, or employee) and the time required to perform companion animals' and food-producing animals' acts. The present study is the first study showing the association between the characteristics of veterinary practices and the turnover, by investigating the price of veterinary acts and the time required

Spatial distribution of psychotic disorders in an urban area of France: an ecological study

Previous analyses of neighbourhood variations of non-affective psychotic disorders (NAPD) have focused mainly on incidence. However, prevalence studies provide important insights on factors associated with disease evolution as well as for healthcare resource allocation. This study aimed to investigate the distribution of prevalent NAPD cases in an urban area in France. The number of cases in each neighbourhood was modelled as a function of potential confounders and ecological variables, namely: migrant density, economic deprivation and social fragmentation. This was modelled using statistical models of increasing complexity: frequentist models (using Poisson and negative binomial regressions), and several Bayesian models. For each model, assumptions validity were checked and compared as to how this fitted to the data, in order to test for possible spatial variation in prevalence. Data showed significant overdispersion (invalidating the Poisson regression model) and residual autocorrelation (suggesting the need to use Bayesian models). The best Bayesian model was Leroux's model (i.e. a model with both strong correlation between neighbouring areas and weaker correlation between areas further apart), with economic deprivation as an explanatory variable (OR = 1.13, 95% CI [1.02-1.25]). In comparison with frequentist methods, the Bayesian model showed a better fit. The number of cases showed non-random spatial distribution and was linked to economic deprivation

Breast carcinoma detection in ex vivo fresh human breast surgical specimens using a fast slide-free confocal microscopy scanner: HIBISCUSS project

Background: New generation ultra-fast fluorescence confocal microscopy allows the ex vivo intraoperative analysis of fresh tissue. The High resolution Imaging for Breast carcInoma detection in ex vivo Specimens after breast Conserving sUrgery by hiStolog Scanner (HIBISCUSS) project aimed to develop an online learning program to recognize the main breast tissue features on ultra-fast fluorescence confocal microscopy images and to evaluate the performance of surgeons and pathologists in diagnosing cancerous and non-cancerous breast tissue in ultra-fast fluorescence confocal microscopy images. Methods: Patients who underwent conservative surgery or mastectomy for breast carcinoma (invasive or in situ lesions) were included. The fresh specimens were stained with a fluorescent dye and imaged using a large field-of-view (20 cm2) ultra-fast fluorescence confocal microscope. Results: One hundred and eighty-one patients were included. The images from 55 patients were annotated to generate learning sheets and images from 126 patients were blindly interpreted by seven surgeons and two pathologists. The time for tissue processing and ultra-fast fluorescence confocal microscopy imaging was between 8 and 10 min. The training program was composed of 110 images divided into nine learning sessions. The final database for blind performance assessment comprised 300 images. The mean duration for one training session and one performance round was 17 and 27 min respectively. The performance of pathologists was almost perfect with 99.6 per cent (standard deviation (s.d.) 5.4 per cent) accuracy. Surgeons' accuracy significantly increased (P = 0.001) from 83 per cent (s.d. 8.4 per cent) in round 1 to 98 per cent (s.d. 4.1 per cent) in round 7 as well as the sensitivity (P = 0.004). Specificity increased without significance from 84 per cent (s.d. 16.7 per cent) in round 1 to 87 per cent (s.d. 16.4 per cent) in round 7 (P = 0.060). Conclusion: Pathologists and surgeons showed a short learning curve in differentiating breast cancer from non-cancerous tissue in ultra-fast fluorescence confocal microscopy images. Performance assessment for both specialties supports ultra-fast fluorescence confocal microscopy evaluation for intraoperative management. Registration number: NCT04976556 (http://www.clinicaltrials.gov)

Clinical predictors of antipsychotic treatment resistance: Development and internal validation of a prognostic prediction model by the STRATA-G consortium

Introduction Our aim was to, firstly, identify characteristics at first-episode of psychosis that are associated with later antipsychotic treatment resistance (TR) and, secondly, to develop a parsimonious prediction model for TR. Methods We combined data from ten prospective, first-episode psychosis cohorts from across Europe and categorised patients as TR or non-treatment resistant (NTR) after a mean follow up of 4.18 years (s.d. = 3.20) for secondary data analysis. We identified a list of potential predictors from clinical and demographic data recorded at first-episode. These potential predictors were entered in two models: a multivariable logistic regression to identify which were independently associated with TR and a penalised logistic regression, which performed variable selection, to produce a parsimonious prediction model. This model was internally validated using a 5-fold, 50-repeat cross-validation optimism-correction. Results Our sample consisted of N = 2216 participants of which 385 (17 %) developed TR. Younger age of psychosis onset and fewer years in education were independently associated with increased odds of developing TR. The prediction model selected 7 out of 17 variables that, when combined, could quantify the risk of being TR better than chance. These included age of onset, years in education, gender, BMI, relationship status, alcohol use, and positive symptoms. The optimism-corrected area under the curve was 0.59 (accuracy = 64 %, sensitivity = 48 %, and specificity = 76 %). Implications Our findings show that treatment resistance can be predicted, at first-episode of psychosis. Pending a model update and external validation, we demonstrate the potential value of prediction models for TR.Funding: This work was supported by a Stratified Medicine Programme grant to JHM from the Medical Research Council (grant number MR/L011794/1 which funded the research and supported S.E.S., D.A., A.F.P, L.K., R.M.M., D.S., J.T.R.W, & J.H.M.); funding from the National Institute for Health Research Biomedical Research Centre at South London and Maudsley National Health Service Foundation Trust and King's College London to D.A. and D.S; and funding from the Collaboration for Leadership in Applied Health Research and Care (CLAHRC) South London at King's College Hospital National Health Service Foundation Trust to S.E.S. The views expressed are those of the author(s) and not necessarily those of the Medical Research Council, National Health Service, the National Institute for Health Research, or the Department of Health. The AESOP (London, UK) cohort was funded by the UK Medical Research Council (Ref: G0500817). The Belfast (UK) cohort was funded by the Research and Development Office of Northern Ireland. The Bologna (Italy) cohort was funded by the European Community's Seventh Framework Program under grant agreement (agreement No.HEALTH-F2-2010–241909, Project EU-GEI). The GAP (London, UK) cohort was funded by the UK National Institute of Health Research(NIHR) Specialist Biomedical Research Centre for Mental Health, South London and Maudsley NHS Mental Health Foundation Trust (SLaM) and the Institute of Psychiatry, Psychology, and Neuroscience at King's College London; Psychiatry Research Trust; Maudsley Charity Research Fund; and the European Community's Seventh Framework Program grant (agreement No. HEALTH-F2-2009-241909, Project EU-GEI). The Lausanne (Switzerland) cohort was funded by the Swiss National Science Foundation (no. 320030_135736/1 to P.C. and K.Q.D., no 320030-120686, 324730-144064 and 320030-173211 to C.B.E and P.C., and no 171804 to LA); National Center of Competence in Research (NCCR) “SYNAPSY - The Synaptic Bases of Mental Diseases” from the Swiss National Science Foundation (no 51AU40_125759 to PC and KQD); and Fondation Alamaya (to KQD). The Oslo (Norway) cohort was funded by the Research Council of Norway (#223273/F50, under the Centers of Excellence funding scheme, #300309, #283798) and the South-Eastern Norway Regional Health Authority (#2006233, #2006258, #2011085, #2014102, #2015088 to IM, #2017-112). The Paris (France) cohort was funded by European Community's Seventh Framework Program grant (agreement No. HEALTH-F2-2010–241909, Project EU-GEI). The Prague (Czech Republic) cohort was funded by the Ministry of Health of the Czech Republic (Grant Number: NU20-04-00393). The Santander (Spain) cohort was funded by the following grants (to B.C.F): Instituto de Salud Carlos III, FIS 00/3095, PI020499, PI050427, PI060507, Plan Nacional de Drogas Research Grant 2005-Orden sco/3246/2004, and SENY Fundatio Research Grant CI 2005-0308007, Fundacion Marques de Valdecilla A/02/07 and API07/011. SAF2016-76046-R and SAF2013-46292-R (MINECO and FEDER). The West London (UK) cohort was funded The Wellcome Trust (Grant Number: 042025; 052247; 064607)

Cognitive performance at first episode of psychosis and the relationship with future treatment resistance: Evidence from an international prospective cohort study

Background: Antipsychotic treatment resistance affects up to a third of individuals with schizophrenia, with recent research finding systematic biological differences between antipsychotic resistant and responsive patients. Our aim was to determine whether cognitive impairment at first episode significantly differs between future antipsychotic responders and resistant cases. Methods: Analysis of data from seven international cohorts of first-episode psychosis (FEP) with cognitive data at baseline (N = 683) and follow-up data on antipsychotic treatment response: 605 treatment responsive and 78 treatment resistant cases. Cognitive measures were grouped into seven cognitive domains based on the preexisting literature. We ran multiple imputation for missing data and used logistic regression to test for associations between cognitive performance at FEP and treatment resistant status at follow-up. Results: On average patients who were future classified as treatment resistant reported poorer performance across most cognitive domains at baseline. Univariate logistic regressions showed that antipsychotic treatment resistance cases had significantly poorer IQ/general cognitive functioning at FEP (OR = 0.70, p = .003). These findings remained significant after adjusting for additional variables in multivariable analyses (OR = 0.76, p = .049). Conclusions: Although replication in larger studies is required, it appears that deficits in IQ/general cognitive functioning at first episode are associated with future treatment resistance. Cognitive variables may be able to provide further insight into neurodevelopmental factors associated with treatment resistance or act as early predictors of treatment resistance, which could allow prompt identification of refractory illness and timely interventions.Funding: This work was supported by a Stratified Medicine Programme grant to J.H.M from the Medical Research Council (grant number MR/L011794/1 which funded the research and supported S.E.S., A.F.P., R.M.M., J.T.R.W. & J.H.M.) E.M’s PhD is funded by the MRC-doctoral training partnership studentship in Biomedical Sciences at King’s College London. J.H.M, E.K, R.M.M are part funded by the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. A.P.K. is funded by the NIHR Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. O.A. is further funded by an NIHR Post-Doctoral Fellowship (PDF2018-11-ST2-020). The views expressed are those of the authors and not necessarily those of the NHS, the MRC, the NIHR or the Department of Health. E.M.J. is supported by the UCL/UCLH Biomedical Research Centre. The AESOP (London, UK) cohort was funded by the UK Medical Research Council (Ref: G0500817). The Bologna (Italy) cohort was funded by the European Community’s Seventh Framework Program under grant agreement (agreement No. HEALTH-F2-2010–241909, Project EU-GEI). The GAP (London, UK) cohort was funded by the UK National Institute of Health Research (NIHR) Specialist Biomedical Research Centre for Mental Health, South London and Maudsley NHS Mental Health Foundation Trust (SLaM) and the Institute of Psychiatry, Psychology, and Neuroscience at King’s College London; Psychiatry Research Trust; Maudsley Charity Research Fund; and the European Community’s Seventh Framework Program grant (agreement No. HEALTH-F2-2009-241909, Project EU-GEI). The Oslo (Norway) cohort was funded by the Stiftelsen KG Jebsen, Research Council of Norway (#223273, under the Centers of Excellence funding scheme, and #300309, #283798) and the South-Eastern Norway Regional Health Authority (#2006233, #2006258, #2011085, #2014102, #2015088, #2017-112). The Paris (France) cohort was funded by European Community’s Seventh Framework Program grant (agreement No. HEALTHF2-2010–241909, Project EU-GEI). The Santander (Spain) cohort was funded by the following grants (to B.C.F): Instituto de Salud Carlos III, FIS 00/3095, PI020499, PI050427, PI060507, Plan Nacional de Drogas Research Grant 2005-Orden sco/3246/2004, and SENY Fundatio Research Grant CI 2005-0308007, Fundacion Marques de Valdecilla A/02/07 and API07/011. SAF2016-76046-R and SAF2013-46292-R (MINECO and FEDER). The West London (UK) cohort was funded The Wellcome Trust (Grant Numbers: 042025; 052247; 064607)