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Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in‐house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV‐A71, echovirus 30, coxsackie A virus 21, and EV‐D68), HPeV3, and specificity controls. Reported results from 48 in‐house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In‐house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10−5). EV‐specific PCRs showed low cross‐reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in‐house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point‐of‐care tests. [ABSTRACT FROM AUTHOR]

Cost-benefit analyses ( CBA) of flood management plans usually require estimating expected annual flood damages on a study area and rely on a complex modelling chain, including hydrological, hydraulic and economic modelling, as well as geographic information system-based spatial analysis. As most model-based assessments, these CBA are fraught with uncertainty. In this paper, we consider as a case study the CBA of a set of flood control structural measures on the Orb Delta, France. We demonstrate the use of variance-based global sensitivity analysis to (i) propagate uncertainty sources through the modelling chain and assess their overall impact on the outcomes of the CBA, and (ii) rank uncertainty sources according to their contribution to the variance of the CBA outcomes. All uncertainty sources prove to explain a significant share of the overall output variance. Results show that the ranking of uncertainty sources depends not only on the economic sector considered (private housing, agricultural land, other economic activities), but also on a number of averaging-out effects controlled by the number and surface area of the assets considered, the number of land use types or the number of damage functions. [ABSTRACT FROM AUTHOR]

Since the first case described in 1946, fewer than 100 cases of giant colonic diverticula have been reported in the literature. We discuss the clinical, radiologic, and pathologic findings in a case of giant colonic diverticulum and review the etiology and differential diagnosis. [ABSTRACT FROM AUTHOR]

The study of runoff is a crucial issue because it is closely related to flooding, water quality and erosion. In cultivated catchments, agricultural ditch drainage networks are known to influence runoff. As anthropogenic elements, agricultural ditch drainage networks can therefore be altered to better manage surface runoff in cultivated catchments. However, the relationship between the spatial configuration, i.e. the density and the topology, of agricultural ditch drainage networks and surface runoff in cultivated catchments is not understood. We studied this relationship by using a random network simulator that was coupled to a distributed hydrological model. The simulations explored a large variety of spatial configurations corresponding to a thousand stochastic agricultural ditch drainage networks on a 6.4 km² Mediterranean cultivated catchment. Next, several distributed hydrological functions were used to compute water flow paths and runoff for each simulation. The results showed that (i) denser networks increased the drained volume and the peak discharge and decreased hillslopes runoff, (ii) greater network density did not affect the surface runoff any further above a given network density, (iii) the correlation between network density and runoff was weaker for small subcatchments (< 2 km²) where the variability in the drained area that resulted from changes in agricultural ditch drainage networks increased the variability of runoff and (iv) the actual agricultural ditch drainage network appeared to be well optimized for managing runoff as compared with the simulated networks. Finally, our results highlighted the role of agricultural ditch drainage networks in intercepting and decreasing overland flow on hillslopes and increasing runoff in drainage networks. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Natural hazards, due to climate change, are particularly damaging in urban areas because of interdependencies of their networks. So, urban resilience has to face up to climate risks. The most impacting phenomenon is the urban heat island (UHI) effect. The storage capacity of heat is depending on shapes of buildings, public spaces, spatial organization, transport or even industrial activities. So, adaptive strategies for improving urban climate could be possible in different ways. In the framework of the French project Resilis, this study characterises urban vulnerability and resilience in terms of energy needs of buildings and outside urban comfort according to the IPCC carbon dioxide emission scenarios B2 and A2 for the period 2050--2100 for 10 French cities. The evolutions of four climate indicators in terms of heating and cooling needs and number of hours when the temperature is above 28 °C are then obtained for each city to analyse climate risks and their impacts in urban environment. [ABSTRACT FROM AUTHOR]

Airborne hyperspectral imagery has been recently proved to be a successful technique for predicting soil properties of the bare soil surfaces that are usually scattered in the landscape. This new soil covariate could much improve the digital soil mapping (DSM) of soil properties over larger areas. To illustrate this, we experimented with digital soil mapping in a 24.6-km2 area located in the vineyard plain of Languedoc. As input data, we used 200 points with clay content measurements and 192 bare soil fields representing 3.5% of the total area in which the clay contents of the soil surface were successfully mapped at 5-m resolution by hyperspectral remote sensing. The clay contents were estimated from CR2206, a spectrometric indicator that quantifies specific absorption features of clay at 2206 nm. We demonstrated by cross-validation that the co-kriging procedure based on our co-regionalization model provided accurate error estimates at the clay measurement sites. Then, we applied a block co-kriging model to map the mean clay content at increasing resolutions (50 , 100, 250 and 500 m). The results showed the following: (i) using hyperspectral data significantly increased the accuracy of the mean clay content estimations; (ii) a block co-kriging procedure with reliable estimates of error variance can be used to estimate mean clay contents over larger areas and at coarser resolutions with acceptable and predictable errors and (iii) various maps can be produced that represent different compromises between prediction accuracy and spatial resolution. [ABSTRACT FROM AUTHOR]

Background Skin cancer surgery is usually performed on the face, and more specifically on and around the midfacial apertures. Each defect generated by the exeresis of a face tumor can be repaired by various advancement, rotation or transposition flaps techniques. Therefore the choice of the closure axis of a defect and its cicatricial and orificial consequences is decisive. Results The closure of a defect is usually made by symmetrically suturing its edges, across the incision axis according to the rule of halves. However, the closure axis of a defect is intentional and characterized by the subcutaneous suture axis which determines the induced tension orientation, and thus the possible displacement of the aperture free margins. The horizontal stretching principle guarantees the lack of impact on the 3 major apertures of the midfacial frame: eye, nostril and mouth. Conclusions This biomechanical concept is decisive to repair midfacial defect with functional and aesthetic results. It also provides objective arguments for the reparative techniques prioritization and the ability to codify those to be recommended as first-line treatment in the surgical management of the face cutaneous tumours. [ABSTRACT FROM AUTHOR]

This paper presents methods to extract badlands thalwegs network from regular grid DTM by combining terrain morphology indices to a drainage algorithm. The computation of a continuous vector network will permit the study of the badlands spatial pat- terns. These methods aim at delineating a thalweg only where the DTM denotes a significant curvature with respect to DTM accuracy. It relies on three major steps. Firstly, discontinuous concave areas are detected from the DTM using morphological criteria; the plan curvature and the convergence index. Secondly, the concave areas are connected using a drainage algorithm which provides continuous and tree-structured thick scheme. We assume that these areas present physical significance and correspond to a gully floor area. Finally, the thick path is reduced to its main curve and vectorised to obtain a thalwegs network. The methods are applied on both virtual and actual cases DTM. The actual case is a LiDAR DTM of Draix Badlands (French Alps). The obtained networks are quantitatively compared both to the one obtained with usual drainage area criteria and to a reference network. The networks comparison shows the great potential of the convergence index based method for thalwegs network extraction. [ABSTRACT FROM AUTHOR]

This article presents the use of new remote sensing data acquired from airborne full-waveform lidar systems for hydrological applications. Indeed, the knowledge of an accurate topography and a landcover classification is a prior knowledge for any hydrological and erosion model. Badlands tend to be the most significant areas of erosion in the world with the highest erosion rate values. Monitoring and predicting erosion within badland mountainous catchments is highly strategic due to the arising downstream consequences and the need for natural hazard mitigation engineering. Additionally, beyond the elevation information, full-waveform lidar data are processed to extract the amplitude and the width of echoes. They are related to the target reflectance and geometry. We will investigate the relevancy of using lidar-derived Digital Terrain Models (DTMs) and the potentiality of the amplitude and the width information for 3-D landcover classification. Considering the novelty and the complexity of such data, they are presented in details as well as guidelines to process them. The morphological validation of DTMs is then performed via the computation of hydrological indexes and photo-interpretation. Finally, a 3- D landcover classification is performed using a Support Vector Machine classifier. The use of an ortho-rectified optical image in the classification process as well as full-waveform lidar data for hydrological purposes is finally discussed. [ABSTRACT FROM AUTHOR]

Fungal species and toxin contamination were determined in 110 cereal samples (54 maize, 35 wheat, and 21 barley) collected in the southeastern part of Romania from 2002 to 2004. The most frequent fungal contaminants belonged to Aspergillus and Fusarium, and maize was the most contaminated cereal. The main toxigenic species identified were Aspergillus flavus, Aspergillus fumigatus, Fusarium graminearum, and Fusarium culmorum in all cereals and Fusarium verticillioides in maize. The presence of aflatoxin B1 (AFB1, deoxynivalenol (DON), zearalenone (ZEA), fumonisins, and ochratoxin A was determined by enzyme-linked immunosorbent assay. More than 90% of the samples were contaminated with at least one toxin. Around 30% of maize samples were contaminated with AFB1, and in 20% of these samples the level of toxin exceeded that allowed by European Union regulations. In 48 and 42% of samples, levels of DON and ZEA, respectively, exceeded those allowed by the European Union. Neither fumonisins nor ochratoxin A were found in samples from any year or cereal. These results indicate that cereals produced in Romania have a particular pattern of mycoflora and mycotoxin contamination because DON and ZEA in addition to AFB1 were found. [ABSTRACT FROM AUTHOR]

Enteroviruses (EV) are the main etiological agents of aseptic meningitis. Diagnosis is made by detecting the genome using RT-PCR. The aim of the study was to evaluate the impact of a positive diagnosis on the management of infants, children, and adults. During 2005, 442 patients were admitted to hospital with suspected meningitis. Clinical and laboratory data and initial treatment were recorded for all patients with enteroviral meningitis. The turnaround time of tests and the length of hospital stay were analyzed. The results showed that EV-PCR detected EV in 69 patients (16%), 23% (16/69) were adults. About 18% of CSF samples had no pleocytosis. After positive PCR results, 63% of children were discharged immediately (mean 2 hr 30 min) and 95% within 24 hr. Infants and adults were discharged later (after 1.8 and 2 days, respectively). The use of antibiotics was significantly lower in children than in infants and adults. The PCR results allowed discontinuation of antibiotics in 50-60% of all patients treated. Patients received acyclovir in 16% of cases (7% children vs. 50% adults) and 23% (11% vs. 69%) underwent a CT scan. Clinical data were compared between patients whose positive EV-PCR results were available within 24 hr (n = 32) and those whose results were available > 24 hr after collection of CSF (n = 14). Duration of antibiotic treatment (difference: 2.3 days; P = 0.05) was reduced between the two groups. No statistical difference in the length of stay was observed. The EV-PCR assay should be performed daily in hospital laboratory practice and considered as part of the initial management of meningitis. J. Med. Virol. 81:42-48, 2009. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

This article presents the use of new remote sensing data acquired from airborne fullwaveform lidar systems. They are active sensors which record altimeter profiles. This paper introduces a set of methodologies for processing these data. These techniques are then applied to a particular landscape, the badlands, but the methodologies are designed to be applied to any other landscape. Indeed, the knowledge of an accurate topography and a landcover classification is a prior knowledge for any hydrological and erosion model. Badlands tend to be the most significant areas of erosion in the world with the highest erosion rate values. Monitoring and predicting erosion within badland mountainous catchments is highly strategic due to the arising downstream consequences and the need for natural hazard mitigation engineering. Additionaly, beyond the altimeter information, full-waveform lidar data are processed to extract intensity and width of echoes. They are related to the target reflectance and geometry. Wa will investigate the relevancy of using lidar-derived Digital Terrain Models (DTMs) and to investigate the potentiality of the intensity and width information for 3-D landcover classification. Considering the novelty and the complexity of such data, they are presented in details as well as guidelines to process them. DTMs are then validated with field measurements. The morphological validation of DTMs is then performed via the computation of hydrological indexes and photo-interpretation. Finally, a 3-D landcover classification is performed using a Support Vector Machine classifier. The introduction of an ortho-rectified optical image in the classification process as well as full-waveform lidar data for hydrological purposes is then discussed. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the presence and seasonal frequency of various enteric viruses in wastewater treatment. The detection of astrovirus, norovirus, enterovirus, hepatitis A virus (HAV) and rotavirus was carried out by molecular analyses in concentrated water samples collected over 18 months at the entrance and exit of an activated sludge sewage treatment plant. The reverse transcriptase-polymerase chain reaction (RT-PCR) results were confirmed by sequencing, and comparative phylogenetic analysis was performed on the isolated strains. Genomes of human astrovirus and human rotavirus were identified in 26/29 and 11/29 samples of raw sewage, respectively, and in 12/29 and 13/29 treated effluent samples, respectively. Some rotavirus sequences detected in environmental samples were very close to those of clinical strains. Noroviruses, enteroviruses and HAV were not detected during the study period. This could be related to the small sample volume, to the sensitivity of the detection methods or to local epidemiological situations. Frequent detection of viral RNA, whether infectious or not, in the exit effluent of sewage treatment indicates wide dispersion of enteric viruses in the environment, Consequently, viral contamination resulting from the use of these treated waters is a risk that needs to be addressed. [ABSTRACT FROM AUTHOR]

Linear features of agrarian landscapes are the anthropogenic elements such as hedgerows, ditches, and bench terraces that strongly impact agrarian areas' environmental behaviour, especially the ecological and hydrological areas. The need to map these linear elements for environmental impact assessments of agrarian areas is thus increasing since these maps limit the developments of spatial indicators and spatially distributed modelling. Until now, no generic remote sensing methodology has been proposed for such mapping purposes. This research was designed to assess the use of airborne LiDAR data for agrarian landscape linear features mapping. We proposed a methodology that uses LiDAR data in three steps. We first estimated elevation profiles from LiDAR points on a set of pre-located sites. We secondly performed profile shape description with wavelet transform or a watershed algorithm. Finally, we classified the profiles using classification trees with predictors coming from shape analysis. Methodology accuracies were calculated for a ditch network detection problem in a Mediterranean vineyard landscape. LiDAR Toposys data and field survey data for ditch location were collected in June 2002. As ditches are always located on field boundary lattices, elevation profiles were only computed on field boundary sites. Methodologies, using wavelets or the watershed algorithm, gave similar accuracies. Overall accuracy is about 70% with a high ditch omission rate (50%) but low commission rate (15%). The omissions conform to those obtained when performing visual classification of profiles. This high omission rate in ditch detection is therefore due to LiDAR data, not methods. Dense vegetation over ditches during the summertime and the specific LiDAR points spatial sampling design explain these omissions. However, the proposed methodology, especially using wavelets transform, looks transposable for the automatic detection or characterization of other agrarian linear features. [ABSTRACT FROM AUTHOR]

Vine-plot mapping and monitoring are crucial issues in land management, particularly for areas where vineyards are dominant like in some French regions. In this context, the availability of an automatic tool for vineyard detection and characterization would be very useful. The objective of the study is to compare two different approaches to meet this need. The first one uses directional variations of the contrast feature computed from Haralick's co-occurrence matrices and the second one is based on a local Fourier transform. For each pixel, a 'vine index' is computed on a sliding window. To foster large-scale applications, test and validation were carried out on standard very high spatial resolution remote sensing data. 70.8% and 86% of the 271 plots of the study area were correctly classified using the co-occurrence and the frequency method, respectively. Moreover, the latter enabled an accurate determination (less than 3% error) of inter-row width and row orientation. [ABSTRACT FROM AUTHOR]

Background We previously reported high prevalence of hepatitis C virus genotype 5a (HCV 5) (14%) in Central France. Aim To identify the risk factors associated with HCV5 infection and to characterize local HCV5 lineages. Method A case-control study and phylogenetic analysis were conducted. Results In all, 131 HCV5 and 343 HCV non 5 infected patients were enrolled. No HCV5 patient was born in sub-Saharan Africa and only two were injection drug user. HCV5 contamination was associated with living in a rural area called Vic le Comte (VLC) in non-transfused patients (OR = 17.7), with transfusion in patients living outside VLC (OR = 3.8) and with receiving injections in patients from VLC (OR = 3.1). More than 80% of the patients from outside VLC were contaminated by transfusion and those from VLC mainly by an iatrogenic factor – injections performed before 1972 by the local physician. Phylogenetic analysis of HCV5 isolates evidenced no distinct genetic cluster, but close relationships between the isolates of spouse pairs and between blood donors and recipients. Conclusions Our results suggest that HCV5 spread in our district by iatrogenic route before 1972 and then via transfusion to the whole district. Collaborative studies are underway to study viral sequences from different parts of Africa and Europe to estimate the origin of our HCV 5a strains. [ABSTRACT FROM AUTHOR]

This article sets out to demonstrate how boosting can serve as a supervised classification method, and to compare its results with those of conventional methods. The comparison begins with a theoretical example in which several criteria are varied: number of pixels per class, overlapping (or not) of radiometric values between classes, and presence and absence of spatial structuring of classes within the geographical space. The results are then compared with a real case study of land cover based on a multispectral SPOT image of the Sousson catchment area (South of France). It is seen that (1) maximum likelihood gives better results than boosting when the radiometric values for each class are clearly separated. This advantage is lost as the number of pixels per class increases; (2) boosting is systematically better than maximum likelihood in the event of overlapping radiometric variable classes, whether or not there is a spatial structure. [ABSTRACT FROM AUTHOR]

Toxinogenic fungal species can be isolated from dry cured meat products, raising the problem of the direct contamination of these foods by mycotoxins known to be carcinogenic or potent carcinogens. Because the contamination of a food by mycotoxins can be considered a balance between production and degradation, the stability of mycotoxins on dry cured meat was also investigated. This study focused on patulin, ochratoxin A, citrinin, and cyclopiazonic acid that can be produced by fungal species previously isolated from dry cured meat products sold on the French market. We demonstrated that neither patulin nor ochratoxin A was produced on dry meat by toxigenic strains, whereas relatively high amounts of citrinin and cyclopiazonic acid were found after a 16-day incubation period at 20°C (87 and 50 mg/kg, respectively). After direct contamination, the initial content of patulin rapidly decreased to become undetectable after only 6 h of incubation at 20°C. For both citrinin and ochratoxin A, the kinetics of decrease at 20°C was less rapid, and the two toxins presented half-lives of 6 and 120 h, respectively. By contrast, more than 80% of the initial contamination in cyclopiazonic acid was still found on ham after a 192-h incubation period. Toxin stability was not affected by storage at 4°C. These results suggest that growth of toxigenic strains of Penicillium has to be avoided on dry meat products. [ABSTRACT FROM AUTHOR]

Production of aflatoxins by Aspergillus ruber THOM and CHURCH was first reported by KULIK and HOLADAY (1967), although these results have lacked confirmation. In this paper we provide evidence that this fungal strain produces aflatoxins. This finding has implications for food hygiene, especially in countries where such moulds are used in the preparation of foodstuffs. [ABSTRACT FROM AUTHOR]

The metabolism of radio-labelled retinol, retinal and retinoic acid by fresh human dermal fibroblasts have been investigated in vitro. Surgically removed skin biopsies were placed at the air liquid interface, and treated topically for 24 h with retinoids. At the end of the treatment period, epidermis and dermis were separated by heat. Epidermis, dermis and medium were subsequently extracted and resulting fractions were analysed by HPLC. Dermal fibroblast cultures were treated analysed in a comparable manner. Topical application of retinoids resulted in gradient concentrations within the skin. For each fraction, metabolites and unchanged product proportions were determined by HPCL. Agter treatment with retinal and retinal, low but significant amounts of retinoic acid were detected in the epidermis, as well as in the dermis (30 pmol to 90 pmol). In comparison, treatments with retinoic acid itself, led to higher level of retinoic acid in the epidermis and in the dermis ( respectively 2050 and 420 pmol). Cultured human dermal fibroblasts, treated retinol and retinal. formed retinoic acid as well as several other metabolites (retinol esters, reduction of retinal to retinol...). Taken together, our results are consistent with an action of retinal or retinal on the skin via a retinoic acid formation and a metabolic function of the dermis. [ABSTRACT FROM AUTHOR]

The conservation of foodstuffs by chemical or physical methods is now practiced on a wide scale. Certain procedures (drying, use of pesticides) are well proved and are used on an industrial scale, although in certain situations they are not without risk to human health. New techniques (controlled atmospheres, irradiation, fumigation) are in use and will undoubtedly see further development for conservation of seeds and cereals in both industrialized and non-industrialized countries. In the latter case, the use of cost-effective fumigants may be of particular value. Preventive measures for the control of molds in foodstuffs are discussed in this report. [ABSTRACT FROM AUTHOR]

Recently, we have shown that transformation of human keratinocyptes by SV40 virus induces the re-expression of characters found in fetal epidermis and monostratified epithelia. In the present study, TPA was found to alter some features of the human keratinocyte phenotype in a similar manner to SV40 transformation. Indeed, 12-O-tetradecan-oyl-13-phorbol acetate (TPA) treatment induced the expression of cytokeratin no. 8, recognized by the monoclonal antibody TROMA-1, which is present in fetal epidermis and/or monostratified epithelia only, and fibronectin expression. However, TPA and SV40 transformation had specific non-overlapping effects. For example, TPA did not prevent terminal differentiation and stratification, as SV40-transfor-mation did, but stimulated these processes. Moreover, TPA was found to induce additional changes in SV40-transformed keratinocytes. In particular it provoked the individualization of cells within the colonies. This effect was seen as little as 1 h after treatment and was reversible. This cellular alteration was accompanied by the reorganization of actin and by a decrease in the number of desmosomes; these changes were not observed after treatment of normal keratinocytes with TPA. These observations lead to the conclusion that TPA is able to trigger cellular responses which cannot be induced by SV40 products alone, but that TPA and some SV40 products can cooperate to elicit new responses, which could reflect a higher state of malignancy. [ABSTRACT FROM PUBLISHER]

Properties of proton diffractive dissociation have been investigated for four-prong final states in proton-proton reactions at 360 GeV/c, in particular for pp→ ppππ mπ( m=0,1,2). Mass distributions and decay angular distributions are given. The decay of the diffractive system is seen to be very anisotropic, and large p is suppressed at higher masses. It is found that the 'pomeron' couples with a single valence quark of the incident proton, but indications for a diquark-pomeron coupling are also found. Similarities with fragmentation in lepton-hadron deep inelastic scattering are underlined. [ABSTRACT FROM AUTHOR]

The inclusive production of vector mesons (charged ρ(770), ω(783), ϕ(1020) and neutral K(892)) in π p interactions at 360 GeV/c is studied. The data are based on 160 000 reconstructed events recorded in the NA 27 Experiment using the LEBC-EHS facility at CERN. The production cross sections in the forward hemisphere in c.m.s. and the longitudinal momentum distributions are determined. The results are compared with data obtained at lower energies. [ABSTRACT FROM AUTHOR]

Correlations among identically charged pions were measured for pions produced in p p collisions at 360 GeV/c using the EHS spectrometer. The effective radius for pion production was determined to be 1.02±0.20 fm with a chaoticity factor 0.32±0.08. We attempted to obtain the radii in the directions parallel and perpendicular to the beam axis and found no difference between them. No multiplicity dependence of the radius was observed at this energy. A peak near zero in the four momentum transfer distribution showed significant deviation from a single Gaussian. The results of an analysis of the three like pion enhancement were consistent with those for two pions. [ABSTRACT FROM AUTHOR]

A comparative analysis of the global properties of 400 GeV/c proton-proton interactions with and without charm production is presented. Multiplicities, momentum distributions, sphericity and thrust of these interactions are compared. [ABSTRACT FROM AUTHOR]

A study of the properties of charm particles produced in 400 GeV/c pp interactions is reported. The experiment was performed using the high resolution hydrogen bubble chamber LEBC in association with the European Hybrid Spectrometer at the CERN SPS. Details of the experimental set-up and operational procedures are given and the methods to extract samples of charm decays are discussed. Results are presented on the intrinsic properties of charm particles (masses, lifetimes, decay modes and branching ratios), adding, whenever appropriate, the relevant information obtained in a similar study made with 360 GeV/c π p interactions. The hadroproduction properties of charm states (total and differential cross sections, correlations) are presented and discussed in the context of current QCD inspired phenomenology. [ABSTRACT FROM AUTHOR]

Multiplicity distributions in various rapidity intervals for charged particles produced in collisions of 360 GeV/c protons with aluminium (Al) and gold (Au) targets are presented. The data were analysed separately for the forward and backward hemispheres. Each distribution is well described by a negative binomial distribution. The experimental distributions are compared with the predictions of the multichain model calculated by the Monte Carlo program MCMHA in which the intranuclear cascade process is included, and also with the Lund Monte Carlo FRITIOF. The results of MCMHA reproduce quite well the multiplicity distributions for various rapidity intervals. [ABSTRACT FROM AUTHOR]

Two particle correlations of hadrons produced in 360 GeV/c pp interactions are investigated in the transverse plane and in rapidity. The data were obtained at the European hybrid spectrometer equipped with a rapid cycling bubble chamber. The observed transverse and rapidity correlations are compared with the one string LUND-and a two string dual parton-model. These models predict in general stronger correlations in the transverse plane and much weaker correlations in rapidity than found in the data. The LUND-FRITIOF-and multichain dual parton models provide a better reproduction of the data, although the agreement is not yet satisfactory. Only the UA5 cluster model GENCL shows agreement with the data. [ABSTRACT FROM AUTHOR]

Charm data from 360 GeV/c π p and 400 GeV/c pp interactions are used to give results on D-meson branching ratios. The analysis is based on 438 charm events containing 608 spatially resolved charm particle decays. We present topological branching ratios, as well as the following inclusive branching ratios of D-mesons into kaons: and the following semi-electronic branching ratios of D-mesons: [ABSTRACT FROM AUTHOR]

In the first holographic bubble chamber experiment - the HOBC experiment - we have accumulated a total of 40000 holograms with particle interactions. We have determined the total charm pair cross section in pN collisions to be 23.3 μb and 3.6 μb for 360 and 200 GeV/c incident protons respectively. We have assumed a linear dependence of the cross section on the atomic number of the target. This experiment has demonstrated the feasibility of holographic recording in small bubble chambers. Assuming that the charm cross section can be described by the standard QCD factorized expression with gluon fusion and quark-antiquark annihilation, we have used our measured charm cross sections with other measurements to determine the effective charmed quark mass to be 1.8 GeV/c. The K factor, which describes the importance of the higher order corrections, is calculated to be 9.8 (See noted added in proof.) [ABSTRACT FROM AUTHOR]

360 GeV/c proton-proton elastic scattering data obtained at the European Hybrid Spectrometer (EHS) are presented. The differential cross sections of elastic and inelastic pp-interactions are studied as a function of the impact parameter. The results are compared to those obtained at other energies. They are interpreted in the framework of a simple geometrical Monte-Carlo model of inelastic collisions considering protons as composite particles having a definite effective radius with valence quarks inside. The model calculations indicate an increase of the effective radii both of protons and of valence quarks and an increase of the proton opacity with increasing energy. Using this model a description of the overlap function for the total cross section is obtained. A mechanism involving interactions of coloured quarks is proposed leading to a splitting of the overlap function for the total cross section into elastic, inelastic and inelastic diffraction components. [ABSTRACT FROM AUTHOR]

We report on a study of ρ and f inclusive production in π− p interactions at 360 GeV/c, using the LEBC-EHS set-up at CERN and reconstructing about 165000 events. The ρ, f and ρ cross sections are determined for x>0, x>0.4 and x>0.6 respectively and the ρ and f Feynman- x distributions and transverse momentum distributions are presented. [ABSTRACT FROM AUTHOR]

The measurement of 12 D and 10 D exclusive branching ratios are presented. The analysis is based on 608 spatially resolved charm particle decays produced in 360 GeV/c π p and 400 GeV/c pp interactions. [ABSTRACT FROM AUTHOR]

Using a quark-diquark fragmentation model, in which either the Field-Feynman or the Lund model is coupled with a quark-diquark distribution function, we study transverse momentum distributions, p, for the inclusive reactions pp→hadron +anything at 360 GeV/c. We find that a primordial mean transverse momentum 〈 k〉≃0.4 GeV/c can well reproduce the p distributions of charged hadrons, π, K, Λ, K and Σ and the Feynman x−p correlations. We confirm that a diquark in a proton plays an important rôle in reproducing the x−p correlation of Λ. [ABSTRACT FROM AUTHOR]

360 GeV/c proton interactions with aluminium (Al) and gold (Au) targets are studied using the European Hybrid Spectrometer (EHS) equipped with the Rapid Cycling Bubble Chamber (RCBC). Multiplicities, rapidity distributions and correlations between leading and other produced particles are presented and compared with Monte Carlo calculations based on the multi-chain and Lund models. [ABSTRACT FROM AUTHOR]

In a study of proton-proton interactions at $$\sqrt s = 26GeV$$ , inclusive distributions of single pions and systems of pions of various charge combinations are presented, as well as the production ratio obtained in association with various trigger particles. The results are compared to current phenomenological models in an attempt to understand multiparticle productions in hadron collisions. [ABSTRACT FROM AUTHOR]

The π and η production is studied in π p interactions at 360 GeV/c. The cross section for π production in the forward hemisphere ( X>0) is σ( π)=(49.7 ± 1.0 ± 1.1) mb and for η with X>0.1, N>2, σ( η)=(3.1 ± 0.5) mb. The ratio of the π to η cross section for X>0.1, N>2 is σ( π)/ σ( η). Results on Feynman X and p distributions are presented. The data were obtained using the European Hybrid Spectrometer EHS and the bubble chamber LEBC at CERN. [ABSTRACT FROM AUTHOR]

Production properties and correlations for K K, K Λ, K ¯Λ and Λ¯Λ systems in 360 GeV/c pp interactions are presented. All rapidity gap distributions are observed to peak at Δ y=0 and the azimuthal angular distributions between the two particles are consistent with being flat. Experimental results are compared with the quark fusion and Lund models of particle production. [ABSTRACT FROM AUTHOR]