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The influence of annealing in air at elevated temperatures on the absorption, luminescence and scintillation characteristics was studied for a set of Ce-doped aluminum garnet and perovskite single crystals. Positive effects consisting mainly in increase of light yield and decrease of afterglow were found to varying extent in all the materials. It is explained by the positive role of created stable Ce 4+ center in scintillation mechanism and by decrease of deep trap concentration based on oxygen vacancies.

Recently, high resolution micro-radiography became of great interest. Very thin scintillator layers of about 5–20 micrometres are used to achieve spatial resolution below one micrometre in application for low energy X-ray micro-radiography [1]. Such thin screens are mainly used in micro-XCT and nano-XCT systems (X-ray Computed Tomography) with either micro-focus X-ray tubes or with synchrotron sources [2]. This work deals with a high-resolution CCD camera together with different optical systems and different single crystal scintillators in application for low energy X-ray micro-radiography. The light distribution on the screen is re-imaged by an optical system (usually represented by classical microscope objective together with a field lens) to a high-resolution CCD or CMOS chip. A theoretical modelling and practical comparison of a camera set-up has been done to investigate the system resolution limits. Thin screens were prepared from YAG:Ce scintillator. The resolution is presented on test patterns. As recent optical systems are limited to the classical microscopy objectives only, we further investigate a possibility to develop a custom-made objective fully dedicated to X-ray imaging application.

The activity of olive microbiota during the oil extraction process could be a critical point for virgin olive oil quality. With the aim to evaluate the role of microbiological activity during the virgin olive oil extraction process, just before oil extraction freshly collected healthy olive fruits were immersed in contaminated water from an olive mill washing tank. The oils extracted were then compared with control samples from the same batch of hand-picked olives. The presence of lactic and enteric bacteria, fungi and Pseudomonas on the surface of olives was proved to be much higher in washed than in control olives, with increments in cfu/g between 2 and 3 orders of magnitude. The biogenesis of volatile compounds and the extraction of olive polyphenols and pigments were significantly influenced by the microbiological profile of olives even without any previous storage. In most cases the effect of olive microbiota on oil characteristics was greater than the effect exerted by malaxation time and temperature. Oils from microbiologically contaminated olives showed lower amounts of C5 volatiles and higher levels of C6 volatiles from the lipoxygenase pathway and some fermentation products. On the other hand, a decrease of chlorophylls, pheophytins, xanthophylls and the ratio chlorophyll/pheophytin was observed in these oils. Likewise, the microbiological activity during oil extraction led to significantly lower amounts of polyphenols, in particular of oleuropein derivatives. These differences in olive oil chemical composition were reflected in oil sensory characteristics by the decrease of the green and bitter attributes and by the modification of the oil color chromatic ordinates.

The potential significance as odorants and markers of olive fruits degradation has been recently pointed out for volatile phenols in virgin olive oil (VOO) and related to the appearance of VOO sensory defects. The few studies carried out in order to elucidate the factors affecting their formation in olive fruits or VOOs, indicated that they could be considered as analytical indices of olive fruits degradation during storage, likely reflecting the microbiological activity. In the present study, the effect of the olive variety (‘Arbequina’, ‘Arbosana’ and ‘Leccino’) on the production of volatile phenols during twelve days of storage in closed plastic bags was evaluated. The different resistance of each variety to the microbiological attach was observed during olive fruit storage, and it was reflected by the evolution of guaiacol, 4-ethylphenol and 4-ethylguaiacol, and related to free acidity values. On the contrary, a scarce dependence on the microbial growth or varietal factors was observed for 4-vinyl derivatives, which appeared more directly related to the time of olives storage. The evolution of volatile phenols found certain correspondence in the sensory characteristics of the resulting VOOs, while the rest of VOO chemical quality indices did not show major variations during fruits storage.

Nineteen Tunisian carob populations from different sites were studied to assess their genetic variation based on pods and kernels measures. The mean of the main descriptive morphological values of pods were weight (16.39 g), length (168.9 mm), width (20.5 mm), lateral thickness (8.3 mm), central thickness (5.8 mm), number of viable kernels (12.26), number of aborted kernels (1.38), kernels weight (0.2 g), kernel length (9.1 mm), kernel width (6.9 mm), kernel thickness (4.1 mm) and kernel yield (17.2%). Most of the parameters measured showed significant differences ( P P The relationship among these characters was analysed by principal component analysis (PCA) resulting in the separation of these populations classed in three grouped and three ungrouped populations.

Volatile phenols are spoilage compounds of many foods, which have also been detected in the volatile fraction of defective virgin olive oils (VOOs). However, their formation in olive fruits or VOOs, as well as the factors affecting their production, has yet to be elucidated. In the present study, the evolution of volatile phenols was monitored for the first time in VOOs obtained from olives stored during different periods under two different conditions of limited aerobiosis. Moreover, their odor activity values (OAVs) in VOO samples were calculated as a first assessment of their sensory importance, and the microbiological profile of the olives' surface was evaluated at each sampling point in order to clarify the possible causes of volatile phenols formation. Although volatile phenols seem to acquire their sensory significance at advanced stages of olives' alteration, they were significantly correlated to the time of olives' storage and in accordance with sensory evaluation, indicating that they could be considered as analytical indices of olive fruits' degradation during storage, likely reflecting the microbiological activity.

Volatile phenols are strong odorants produced by microbial activity and reported in several foods, but very scarce information is available on their presence in virgin olive oils (VOOs) and on their relation with VOO chemical and sensory quality. In the present paper, a factorial experimental design was applied for the development of a suitable solid-phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) analytical method for the analysis of volatile phenols in olive oil. The memory effects demonstrated by SPME fibres required the optimization of desorption conditions to minimize experimental errors. A series of nine volatile phenols were identified and quantified for the first time in VOOs by analyzing samples with distinct off-flavours. Their limits of detection and quantification (microg/kg) were largely below the odour detection thresholds (ODTs) calculated in this study (mg/kg), confirming the capacity of the technique to assess the target compounds at early stages of the oil sensory alteration. The odour activity values (OAVs) of volatile phenols were calculated in VOOs facilitating a first assessment of their potential importance in the aroma of the product.

The characteristic of the thin plate (O38x0.25mm) of scintillation detectors YAP:Ce (YAlO3 doped Ce) and YAG (Y3Al5O12 doped Ce) were tested by using the etalons of alpha, beta and gamma radiation with low energies (241Am, 90Sr, 55Fe...) and a standard 222Rn. Those detectors have been developed in Crytur Ltd. For the measurement was used a specially built test assembly comprising encapsulated scintillation detector with calibrated photomultiplier fixed in a black, variable-volume test chamber. All measurements were conducted under precisely defined geometry. The MC 1256 analyzer was used in 256 channel configuration. The focus was on measurement and assessment of the tested detectors surface characteristics, in relation to the light output, spectral resolution capability and peak-background characteristics [1.2]. The tests included extended time period of monitoring related to impact absorption on the surface of detectors and energy calibration. The end result was the selection of the most suitable surface processing for the thin scintillation detectors. These detectors can be assembled into large area arrays, enabling the increase of the detection efficiency, especially for the Alpha activity measurement in radioactive aerosols. The major advantage of these scintillation detectors is their low production cost compared with semiconductor detectors.

6th International Congress on Hazelnut -- JUN 14-18, 2004 -- Tarragona Reus, SPAIN Ozman-Sullivan, Sebahat/0000-0001-5240-8110; Kazmierski, Andrzej/0000-0003-0189-3229 WOS: 000233635700055 Between 1991 and 1999, mites were surveyed in hazelnut orchards in Turkey. Plant samples, were collected and examined. Samples of leaf litter were also collected from orchards and beneath surrounding hedge plants during winter. Fourteen mite species from 6 families and 2 cohorts, namely Bimichaelia grandis Berlese, Lorryia livshitzi (Kuznetzov), Lorryia obnoxia (Kuznetzov et Zapletina), Lorryia paraobliqua Panou et Emmanouel, Tydeus kochi Oudemans, Tydeus linaroeatus (Schiess), Micro-tydeus beltrani Baker, Homeopronematus staerki (Schruft), Triophtydeus immanis Kuznetzov, Triophtydeus triophthalmus (Oudemans), Cyta grandjeani Gomelauri, Biscirus silvaticus (Kramer), Cunaxoides biscutum Baker et Hoffman, Cunaxoides parvus (Ewing) were identified in this study. Eleven species were reported for the first time in Turkey.

Resume En 1999, en region Rhone-Alpes, dans le cadre de la surveillance de la resistance de S. pneumoniae aux antibiotiques, 35 meningites ont ete repertoriees. Un questionnaire retrospectif a ete adresse a chaque participant. Les CMI a la penicilline, l’amoxicilline et le cefotaxime determinees a l’aide de la galerie ATB-PNEUMO® ou E-test® et les antibiogrammes ont ete interpretes selon les recommandations du CA-SFM. Soixante-trois pour cent des meningites ont ete observees en automne/hiver. L’âge median etait de 38,1 ans (extremes : 1 mois–78 ans), le sex-ratio M/F a 2/5. Huit patients avaient recu des antibiotiques dans les 15 jours precedents ; 22 patients presentaient des facteurs de risque (4 breches, 3 OMA…) ; 23 patients ont ete transferes en reanimation. Les traitements antibiotiques ont ete une C3G + glycopeptide chez 15 des 16 enfants et chez 13 des 19 adultes conformement aux recommandations de consensus. Le diagnostic a ete fait sur l’examen direct du LCR dans 83 % des cas. Les hemocultures etaient positives dans 74,3 % des cas. Le pourcentage de PSDP etait de 48,6 %, avec 17,1 % de souches intermediaires a l’amoxicilline et 14,3 % au cefotaxime. La resistance au trimethoprime-sulfamethoxazole etait de 45,7 %, au chloramphenicol de 30 % et a la fosfomycine de 6,9 %. Toutes les souches etaient sensibles a la rifampicine et a la vancomycine. Parmi les 17 PSDP, 7 souches appartenaient au serotype 6 dont 6 chez les enfants. L’evolution a ete marquee par 7 deces (20 %), tous de sexe masculin, sans facteur de risque chez les 3 enfants ; 6 souches sur 7 etaient peni-S. Six patients (17 %) ont eu des sequelles auditives et/ou neurologiques. Cette etude montre que presque la moitie des souches isolees de meningites, en region Rhone-Alpes, sont de sensibilite diminuee a la penicilline et confirme la frequence des survenues de sequelles qui, comme les deces, ne sont pas lies a la resistance des souches aux antibiotiques.

Sensory characterisation of virgin olive oil is completely standardised in the European Union. The sensory profile used to evaluate samples is made up of 16 descriptors, three of them being generic. These three attributes [Other ripe fruit(s), Other positive attribute(s) and Other negative attribute(s)] could be of great additional interest in the characterisation of different samples. However, as they are not specifically defined it is difficult to reach a descriptor consensus among assessors evaluating the samples. This situation is similar to that produced when using a Free Choice Profile and so the Generalised Procrustes Analysis (GPA) could be extremely useful in obtaining all the information contained in these three generic descriptors. In this study GPA was applied to the descriptors generated by a 25 member expert panel under the headings Other ripe fruits and Other positive attributes when evaluating 11 samples of virgin olive oil from the variety ‘Arbequina’ grown in three different regions. The Generalised Procrustes Analysis was efficient in the sensory characterisation of the 11 samples studied using the information provided by the two positive generic descriptors included in the official sensory profile. The overall result was equivalent to that obtained using Correspondence Analysis, although the GPA gave more information since it also included the intensity of each of the descriptors and was less affected by odd descriptors. This technique was as useful in the characterisation of the samples as the other six positive descriptors defined in the official sensory profile (Olive fruity, Apple, Green, Sweet, Bitter, and Pungent), providing additional information of great scientific and commercial interest.

Objective – The authors wanted to determine the state of pneumococcus resistance in the Rhone-Alpes region, in 1999. Patients and method – One thousand eight hundred and thirteen strains of S. pneumoniae (Sp) (64.5% adults, 35.5% children) were collected by 31 clinical microbiological laboratories. Susceptibility to oxacillin of the strains (isolated in pathogenic conditions) was measured according to CA-SFM standards. The MICs of penicillin (P), amoxicillin (AMX), and cefotaxime (CTX) were determined (E-test or ATB-Pneumo gallery) for all strains resistant to penicillin G (PRP). The regional coordinating center checked the MIC and serotype of each PRP strain. Results – The prevalence of PRP (MIC > 0.06 mg/L) was 40.5%. Resistance (I + R) to ERY, TET, SXT, and C was respectively 42%, 27.4%, 37.9%, and 19.2%. Among the 9.4% of strains resistant to P (MIC > 1 mg/L), 63.3% were intermediate to AMX (0.5 2 mg/L). The multiresistance was frequent in PRP: 70.7% to ERY, 72% to TET, 45% to SXT, 32.8% to C, and only 0.4% to RIF. PRP of serotype 14 (23.8%) were the most frequent, followed by serotypes 6 (16%), 23 (15.7%), 9 (12%), 19 (11%), and 15 (2.8%). Discussion – PRP have been increasing since 1997 (29.5% vs. 40.5%), AMX-R strains are still infrequent (2%), and CTX-R strains even though rare (0.3%) are now isolated.

En 1999, dans le cadre de la surveillance de la resistance de S. pneumoniae aux antibiotiques, les 877 souches oxacilline < 26 mm (5 μg) ou de sensibilite diminuee a la penicilline (PSDP) ont fait l'objet d'une determination des CMI a trois β-lactamines par E-test® pour 220 souches, ou par ATB-PNEUMO® pour 657 souches dans les 31 centres collaborateurs de la region Rhone-Alpes. Ces souches etaient ensuite centralisees au site coordonnateur charge de determiner ces CMI par la technique de reference de dilution en milieu gelose. La concordance a ± 1 dilution des deux tests avec la technique de reference etait respectivement pour ATB-PNEUMO® et E-test® de 89% versus 84 % pour la penicilline (difference non significative), de 86% vs 79% pour l'amoxicilline (p < 0,01) et de 91 % vs 86% pour le cefotaxime (p = 0,03). Lors de la categorisation therapeutique, les differences etaient significatives (p < 0,001) pour amoxicilline (85 % vs 71 %) et cefotaxime (82 % vs 75 %) mais pas pour la penicilline (73 % vs 78 %). La methode de l'erreur standard avec transformation angulaire a ete utilisee pour comparer la sensibilite et la specificite des deux methodes lors de la categorisation therapeutique des souches. La methode ATB-PNEUMO® est plus sensible que le E-test® pour la detection des souches sensibles a P (90 vs 73%), a AMX (83 vs 78%) et au CTX (80 vs 72%) et pour les souches intermediaires a AMX (90 vs 78 %). Elle est aussi plus specifique que le E-test® pour les souches AMX-S (85 vs 53 %) et CTX-S (72 vs 42 %). En revanche, le E-test® est plus specifique que ATB-PNEUMO® pour la detection des souches Peni-R (94 vs 86 %). Le nombre de souches CTX-R etant trop restreint, la sensibilite et la specificite n'ont pu etre determinees. Enfin, la specificite des deux methodes est equivalente pour la detection des souches Peni-S, AMX-R et CTX-I.

Resume Objectif – Determiner l'etat de la resistance du pneumocoque en 1999 dans la region Rhone-Alpes. Patients et methodes – Mille huit cent treize souches de Streptococcus pneumoniae (64,5 % adultes, 35,5 % enfants) ont ete collectees par 31 laboratoires. La sensibilite a l'oxacilline des souches isolees en situation pathogene a ete mesuree (normes du CA-SFM). Pour toutes les souches de sensibilite diminuee a la penicilline G (PSDP), les CMI a la penicilline G, l'amoxicilline et au cefotaxime ont ete determinees (E-test ou ATB-Pneumo). Le centre coordinateur a controle la CMI ainsi que le serotypage des souches de PSDP. Resultats – La prevalence des PSDP etait de 40,5 %. Parmi les 9,4 % de resistants, 63,3 % etaient intermediaires a l'amoxicilline et 0,8 % resistants au cefotaxime. La resistance a l'erythromycine, tetracycline, cotrimoxazole, chloramphenicol, pristinamycine, rifampicine et fosfomycine etait de 42 %, 27,4 %, 37,9 %, 19,2 %, 1,4 %, 0,6 % et 8 %. La multiresistance chez les PSDP etait de : 70,7 % a l'erythromycine, 72 % a cotrimoxazole, 45 % a tetracycline, 32,8 % au chloramphenicol, 1,8 % a la pristinamycine et 0,4 % a la rifampicine. Les PSDP de serotypes 14 (23,8 %) etaient les plus frequents, puis les serotypes 6 (16 %), 23 (15,7 %), 19 (11 %), et 15 (2,8 %). Discussion – Depuis 1997 les PSDP augmentent (29,5 % versus 40,5 %), les souches resistantes a l'amoxicilline sont encore peu frequentes (2 %) et celles resistantes au cefotaxime (0,3 %) sont maintenant isolees.