Optimal regulation of specialized medical care in a mixed system

We study the optimal public intervention in setting minimum standards of formation for specialized medical care. The abilities the physicians obtain by means of their training allow them to improve their performance as providers of cure and earn some monopoly rents.. Our aim is to characterize the most efficient regulation in this field taking into account different regulatory frameworks. We find that the existing situation in some countries, in which the amount of specialization is controlled, and the costs of this process of specialization are publicly financed, can be supported as the best possible intervention.

Characterisation of neutron spectra in mixed high energy fields in lineal accelerators: response functions validation

Actualment, la resposta de la majoria d’instrumentació operacional i dels dosímetres personals utilitzats en radioprotecció per a la dosimetria neutrònica és altament dependent de l’energia dels espectres neutrònics a analitzar, especialment amb camps neutrònics amb una important component intermitja. En conseqüència, la interpretació de les lectures d’aquests aparells es complicada si no es té un coneixement previ de la distribució espectral de la fluència neutrònica en els punts d’interès. El Grup de Física de les Radiacions de la Universitat Autònoma de Barcelona (GFR-UAB) ha desenvolupat en els últims anys un espectròmetre de neutrons basat en un Sistema d’Esferes Bonner (BSS) amb un contador proporcional d’3He com a detector actiu. Els principals avantatges dels espectròmetres de neutrons per BSS són: la seva resposta isotròpica, la possibilitat de discriminar la component neutrònica de la gamma en camps mixtos, i la seva alta sensibilitat neutrònica als nivells de dosi analitzats. Amb aquestes característiques, els espectròmetres neutrònics per BSS compleixen amb els estándards de les últimes recomanacions de la ICRP i poden ser utilitzats també en el camp de la dosimetria neutrònica per a la mesura de dosis en el rang d’energia que va dels tèrmics fins als 20 MeV, en nou ordres de magnitud. En el marc de la col•laboració entre el GFR - UAB i el Laboratorio Nazionale di Frascati – Istituto Nazionale di Fisica Nucleare (LNF-INFN), ha tingut lloc una experiència comparativa d’espectrometria per BSS amb els feixos quasi monoenergètics de 2.5 MeV i 14 MeV del Fast Neutron Generator de l’ENEA. En l’exercici s’ha determinat l’espectre neutrònic a diferents distàncies del blanc de l’accelerador, aprofitant el codi FRUIT recentment desenvolupat pel grup LNF. Els resultats obtinguts mostren una bona coherència entre els dos espectròmetres i les dades mesurades i simulades.

Pure motives, mixed motives and extensions of motives associated to singular surfaces

We first recall the construction of the Chow motive modelling intersection cohomology of a proper surface X and study its fundamental properties. Using Voevodsky's category of effective geometrical motives, we then study the motive of the exceptional divisor D in a non-singular blow-up of X. If all geometric irreducible components of D are of genus zero, then Voevodsky's formalism allows us to construct certain one-extensions of Chow motives, as canonical subquotients of the motive with compact support of the smooth part of X. Specializing to Hilbert-Blumenthal surfaces, we recover a motivic interpretation of a recent construction of A. Caspar.

Encryption methods using formal power series rings

Recently there has been a great deal of work on noncommutative algebraic cryptography. This involves the use of noncommutative algebraic objects as the platforms for encryption systems. Most of this work, such as the Anshel-Anshel-Goldfeld scheme, the Ko-Lee scheme and the Baumslag-Fine-Xu Modular group scheme use nonabelian groups as the basic algebraic object. Some of these encryption methods have been successful and some have been broken. It has been suggested that at this point further pure group theoretic research, with an eye towards cryptographic applications, is necessary.In the present study we attempt to extend the class of noncommutative algebraic objects to be used in cryptography. In particular we explore several different methods to use a formal power series ring R && x1; :::; xn && in noncommuting variables x1; :::; xn as a base to develop cryptosystems. Although R can be any ring we have in mind formal power series rings over the rationals Q. We use in particular a result of Magnus that a finitely generated free group F has a faithful representation in a quotient of the formal power series ring in noncommuting variables.

Biomedical risk assessment as an aid for smoking cessation.

BACKGROUND: A possible strategy for increasing smoking cessation rates could be to provide smokers who have contact with healthcare systems with feedback on the biomedical or potential future effects of smoking, e.g. measurement of exhaled carbon monoxide (CO), lung function, or genetic susceptibility to lung cancer. OBJECTIVES: To determine the efficacy of biomedical risk assessment provided in addition to various levels of counselling, as a contributing aid to smoking cessation. SEARCH STRATEGY: We systematically searched the Cochrane Collaboration Tobacco Addiction Group Specialized Register, Cochrane Central Register of Controlled Trials 2008 Issue 4, MEDLINE (1966 to January 2009), and EMBASE (1980 to January 2009). We combined methodological terms with terms related to smoking cessation counselling and biomedical measurements. SELECTION CRITERIA: Inclusion criteria were: a randomized controlled trial design; subjects participating in smoking cessation interventions; interventions based on a biomedical test to increase motivation to quit; control groups receiving all other components of intervention; an outcome of smoking cessation rate at least six months after the start of the intervention. DATA COLLECTION AND ANALYSIS: Two assessors independently conducted data extraction on each paper, with disagreements resolved by consensus. Results were expressed as a relative risk (RR) for smoking cessation with 95% confidence intervals (CI). Where appropriate a pooled effect was estimated using a Mantel-Haenszel fixed effect method. MAIN RESULTS: We included eleven trials using a variety of biomedical tests. Two pairs of trials had sufficiently similar recruitment, setting and interventions to calculate a pooled effect; there was no evidence that CO measurement in primary care (RR 1.06, 95% CI 0.85 to 1.32) or spirometry in primary care (RR 1.18, 95% CI 0.77 to 1.81) increased cessation rates. We did not pool the other seven trials. One trial in primary care detected a significant benefit of lung age feedback after spirometry (RR 2.12; 95% CI 1.24 to 3.62). One trial that used ultrasonography of carotid and femoral arteries and photographs of plaques detected a benefit (RR 2.77; 95% CI 1.04 to 7.41) but enrolled a population of light smokers. Five trials failed to detect evidence of a significant effect. One of these tested CO feedback alone and CO + genetic susceptibility as two different intervention; none of the three possible comparisons detected significant effects. Three others used a combination of CO and spirometry feedback in different settings, and one tested for a genetic marker. AUTHORS' CONCLUSIONS: There is little evidence about the effects of most types of biomedical tests for risk assessment. Spirometry combined with an interpretation of the results in terms of 'lung age' had a significant effect in a single good quality trial. Mixed quality evidence does not support the hypothesis that other types of biomedical risk assessment increase smoking cessation in comparison to standard treatment. Only two pairs of studies were similar enough in term of recruitment, setting, and intervention to allow meta-analysis.

Exploration of the visual system : Part 2. In vivo analysis methods : virtual-reality optomotor system, fundus examination and fluorescent angiography

The mouse has emerged as an animal model for many diseases. At IRO, we have used this animal to understand the development of many eye diseases and treatment of some of them. Precise evaluation of vision is a prerequisite for both these approaches. In this unit we describe three ways to measure vision: testing the optokinetic response, and evaluating the fundus by direct observation and by fluorescent angiography.

Physiotherapy practice in the private sector: organizational characteristics and models.

BACKGROUND: Even if a large proportion of physiotherapists work in the private sector worldwide, very little is known of the organizations within which they practice. Such knowledge is important to help understand contexts of practice and how they influence the quality of services and patient outcomes. The purpose of this study was to: 1) describe characteristics of organizations where physiotherapists practice in the private sector, and 2) explore the existence of a taxonomy of organizational models. METHODS: This was a cross-sectional quantitative survey of 236 randomly-selected physiotherapists. Participants completed a purpose-designed questionnaire online or by telephone, covering organizational vision, resources, structures and practices. Organizational characteristics were analyzed descriptively, while organizational models were identified by multiple correspondence analyses. RESULTS: Most organizations were for-profit (93.2%), located in urban areas (91.5%), and within buildings containing multiple businesses/organizations (76.7%). The majority included multiple providers (89.8%) from diverse professions, mainly physiotherapy assistants (68.7%), massage therapists (67.3%) and osteopaths (50.2%). Four organizational models were identified: 1) solo practice, 2) middle-scale multiprovider, 3) large-scale multiprovider and 4) mixed. CONCLUSIONS: The results of this study provide a detailed description of the organizations where physiotherapists practice, and highlight the importance of human resources in differentiating organizational models. Further research examining the influences of these organizational characteristics and models on outcomes such as physiotherapists' professional practices and patient outcomes are needed.

Liquid chromatography-tandem mass spectrometry (LC/APCI-MS/MS) methods for the quantification of captan and folpet phthalimide metabolites in human plasma and urine.

Captan and folpet are fungicides largely used in agriculture. They have similar chemical structures, except that folpet has an aromatic ring unlike captan. Their half-lives in blood are very short, given that they are readily broken down to tetrahydrophthalimide (THPI) and phthalimide (PI), respectively. Few authors measured these biomarkers in plasma or urine, and analysis was conducted either by gas chromatography coupled to mass spectrometry or liquid chromatography with UV detection. The objective of this study was thus to develop simple, sensitive and specific liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (LC/APCI-MS/MS) methods to quantify both THPI and PI in human plasma and urine. Briefly, deuterated THPI was added as an internal standard and purification was performed by solid-phase extraction followed by LC/APCI-MS/MS analysis in negative ion mode for both compounds. Validation of the methods was conducted using spiked blank plasma and urine samples at concentrations ranging from 1 to 250 μg/L and 1 to 50 μg/L, respectively, along with samples of volunteers and workers exposed to captan or folpet. The methods showed a good linearity (R (2) > 0.99), recovery (on average 90% for THPI and 75% for PI), intra- and inter-day precision (RSD, <15%) and accuracy (<20%), and stability. The limit of detection was 0.58 μg/L in urine and 1.47 μg/L in plasma for THPI and 1.14 and 2.17 μg/L, respectively, for PI. The described methods proved to be accurate and suitable to determine the toxicokinetics of both metabolites in human plasma and urine.

Ecology of sandflies (Diptera: Psychodidae) in a restricted focus of cutaneous leishmaniasis en Northern Venezuela: I. Description of the study area, catching methods and species composition

A study on the ecology of phlebotomine sandfly fauna in a restricted focus of cutaneous leishmaniasis in northern Venezuela was undertaken in order to investigate the species responsible for the transmission. The study area and catching methods for phlebotomine sandflies are described. A total of 9,061 females and 1,662 males were collected during a year-term study. 12 species of Lutzomya and 1 species of Brumptomya sp. were identified. Absolute and relative abundance and ocurrence for each species were determined. The rel ative occurrence allowed to distinguish the common species, viz. L. panamensis, L. ovallesi, L. gomezi, L. tinidadensis, L. atroclavata, L. cayennensis, L. shannoni and L. olmeca bicolor from the rare species vis., L. punctigeniculata, L. rangeliana, L. evansi and L. dubitans. General comments on the species composition of the sandfly fauna in this locality are made.

Empirical studies in industrial location: an assessment of their methods and results

This paper surveys recent evidence on the determinants of (national and/or foreign) industrial location. We find that the basic analytical framework has remained essentially unaltered since the early contributions of the early 1980's while, in contrast, there have been significant advances in the quality of the data and, to a lesser extent, the econometric modelling. We also identify certain determinants (neoclassical and institutional factors) that tend to provide largely consistent results across the reviewed studies. In light of this evidence, we finally suggest future lines of research.

New methods for detecting antibiotic resistant bacteria and preventing their spread

Methicillin resistant Staphylococcus aureus (MRSA) bacteria have emerged in the early 1980's in numerous health care institutions around the world. The main transmission mechanism within hospitals and healthcare facilities is through the hands of health care workers. Resistant to several antibiotics, the MRSA is one of the most feared pathogens in the hospital setting since it is very difficult to eradicate with the standard treatments. There are still a limited number of anti-MRSA antibiotics but the first cases of resistance to these compounds have already been reported and their frequency is likely to increase in the coming years. Every year, the MRSA infections result in major human and financial costs, due to the high associated mortality and expenses related to the required care. Measures towards a faster detection of resistant bacteria and establishment of appropriate antibiotic treatment parameters are fundamental. Also as part as infection prevention, diminution of bacteria present on the commonly touched surfaces could also limit the spread and selection of antibiotic resistant bacteria. During my thesis, projects were developed around MRSA and antibiotic resistance investigation using innovative technologies. The thesis was subdivided in three main parts with the use of atomic force microscopy AFM for antibiotic resistance detection in part 1, the importance of the bacterial inoculum size in the selection of antibiotic resistance in part 2 and the testing of antimicrobial surfaces creating by sputtering copper onto polyester in part 3. In part 1 the AFM was used two different ways, first for the measurement of stiffness (elasticity) of bacteria and second as a nanosensor for antibiotic susceptibility testing. The stiffness of MRSA with different susceptibility profiles to vancomycin was investigated using the stiffness tomography mode of the AFM and results have demonstrated and increased stiffness in the vancomycin resistant strains that also paralleled with increased thickness of the bacterial cell wall. Parts of the AFM were also used to build a new antibiotic susceptibility-testing device. This nano sensor was able to measure vibrations emitted from living bacteria that ceased definitively upon antibiotic exposure to which they were susceptible but restarted after antibiotic removal to which they were resistant, allowing in a matter of minute the assessment of antibiotic susceptibility determination. In part 2 the inoculum effect (IE) of vancomycin, daptomycin and linezolid and its importance in antibiotic resistance selection was investigated with MRSA during a 15 days of cycling experiment. Results indicated that a high bacterial inoculum and a prolonged antibiotic exposure were two key factors in the in vitro antibiotic resistance selection in MRSA and should be taken into consideration when choosing the drug treatment. Finally in part 3 bactericidal textile surfaces were investigated against MRSA. Polyesters coated after 160 seconds of copper sputtering have demonstrated a high bactericidal activity reducing the bacterial load of at least 3 logio after one hour of contact. -- Au cours des dernières décennies, des bactéries multirésistantes aux antibiotiques (BMR) ont émergé dans les hôpitaux du monde entier. Depuis lors, le nombre de BMR et la prévalence des infections liées aux soins (IAS) continuent de croître et sont associés à une augmentation des taux de morbidité et de mortalité ainsi qu'à des coûts élevés. De plus, le nombre de résistance à différentes classes d'antibiotiques a également augmenté parmi les BMR, limitant ainsi les options thérapeutiques disponibles lorsqu'elles ont liées a des infections. Des mesures visant une détection plus rapide des bactéries résistantes ainsi que l'établissement des paramètres de traitement antibiotiques adéquats sont primordiales lors d'infections déjà présentes. Dans une optique de prévention, la diminution des bactéries présentes sur les surfaces communément touchées pourrait aussi freiner la dissémination et l'évolution des bactéries résistantes. Durant ma thèse, différents projets incluant des nouvelles technologies et évoluant autour de la résistance antibiotique ont été traités. Des nouvelles technologies telles que le microscope à force atomique (AFM) et la pulvérisation cathodique de cuivre (PCC) ont été utilisées, et le Staphylococcus aureus résistant à la méticilline (SARM) a été la principale BMR étudiée. Deux grandes lignes de recherche ont été développées; la première visant à détecter la résistance antibiotique plus rapidement avec l'AFM et la seconde visant à prévenir la dissémination des BMR avec des surfaces crées grâce à la PCC. L'AFM a tout d'abord été utilisé en tant que microscope à sonde locale afin d'investiguer la résistance à la vancomycine chez les SARMs. Les résultats ont démontré que la rigidité de la paroi augmentait avec la résistance à la vancomycine et que celle-ci corrélait aussi avec une augmentation de l'épaisseur des parois, vérifiée grâce à la microscopie électronique. Des parties d'un AFM ont été ensuite utilisées afin de créer un nouveau dispositif de test de sensibilité aux antibiotiques, un nanocapteur. Ce nanocapteur mesure des vibrations produites par les bactéries vivantes. Après l'ajout d'antibiotique, les vibrations cessent définitivement chez les bactéries sensibles à l'antibiotique. En revanche pour les bactéries résistantes, les vibrations reprennent après le retrait de l'antibiotique dans le milieu permettant ainsi, en l'espace de minutes de détecter la sensibilité de la bactérie à un antibiotique. La PCC a été utilisée afin de créer des surfaces bactéricides pour la prévention de la viabilité des BMR sur des surfaces inertes. Des polyesters finement recouverts de cuivre (Cu), connu pour ses propriétés bactéricides, ont été produits et testés contre des SARMs. Une méthode de détection de viabilité des bactéries sur ces surfaces a été mise au point, et les polyesters obtenus après 160 secondes de pulvérisation au Cu ont démontré une excellente activité bactéricide, diminuant la charge bactérienne d'au moins 3 logio après une heure de contact. En conclusion, l'utilisation de nouvelles technologies nous a permis d'évoluer vers de méthodes de détection de la résistance antibiotique plus rapides ainsi que vers le développement d'un nouveau type de surface bactéricide, dans le but d'améliorer le diagnostic et la gestion des BMR.

I have faith in my thing, you know what I mean? Mixed method elements on individual investments on religious markets.

In contemporary society, religious signification and secular systems mix and influence each other. Holistic conceptions of a world in which man is integrated harmoniously with nature meet representations of a world run by an immanent God. On the market of the various systems, the individual goes from one system to another, following his immediate needs and expectations without necessarily leaving any marks in a meaningful long term system. This article presents the first results of an ongoing research in Switzerland on contemporary religion focusing on (new) paths of socialization of modern that individuals and the various (non-) belief systems that they simultaneously develop