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International audience; We describe the design, fabrication and measurements of an axisymmetric dielectric lens, featuring a sectorial radiation pattern at 77 GHz. It will be used as the primary feed of a lens-based compact antenna test range (CATR). Due to symmetry of revolution, the sectorial lens profile can be designed in one dimension by using phase only control. The phase variation is echoed on the lens depth. The resulting stepped lens is simulated using France Telecom Orange Labs SRSRD software (¿in-house¿ software developed for dielectric axisymmetric radiating structures) and measured in an anechoic chamber at 77 GHz. Two lenses were fabricated with different materials: PVC and polyurethane, respectively. Good agreements were obtained between simulations and measurements. Less than 0.2 dB ripple in the central beam are obtained for the polyurethane lens although relatively high secondary lobes occur at 11°. Comparisons between the near field of a CATR illuminated by a small horn providing a uniform amplitude taper and the sectorial lens are conducted using numerical simulations. Results show that on-axis oscillations are reduced from 6 to 1 dB with the sectorial lens.

Background: To test whether supplementary antioxidants and n–3 fatty acids, alone or in combination, could improve functional status in stroke survivors. Methods: We performed a randomized, double-blind, placebo-controlled clinical trial in 72 stroke patients (47 males; age 65.3 ± 12.9 years) admitted to a rehabilitation hospital for sequelae of first-ever ischemic stroke, and divided them into 4 subgroups. Group 1 patients received daily oral antioxidants, group 2 received n–3 polyunsaturated fatty acids, group 3 both supplements, and group 4 placebo, all for 12 months. No difference at baseline was observed among groups in neurological severity or in disability. All measures were repeated after 6 and 12 months of treatment. All major clinical events were recorded. Results: At baseline, 25% of the patients had a low plasma vitamin status, and 48.5% was at risk of undernutrition. At the 1-year follow-up, we observed a trend for lower mortality (p = 0.060) in subgroups treated with n–3 fatty acids, but without significant differences in rehabilitation result status among groups. Conclusions: Malnutrition is widely observed in patients admitted to a rehabilitative hospital for stroke rehabilitation, and dietary supplementation, even if not able to improve rehabilitation results, is likely to reduce mortality at the 1-year follow-up.

An effective liquid chromatographic method with tandem mass spectrometric (LC–MS/MS) detection and identification is presented for the determination of chloramphenicol (CAP) in honey. After a preliminary dissolution in water, samples were extracted with a mixture of dichloromethane/acetone and evaporated to dryness; the following clean up was carried out on an octadecyl (C18) SPE cartridge. CAP was determined by LC–MS/MS, using electrospray ionization in the negative ion mode (ESI−). The column was a LUNA Phenomenex with a mixture of methanol-aqueous ammonium acetate (60:40, v/v) as a mobile phase. Honey samples were fortified at CAP levels 0.30–0.45–0.60 μg kg−1 with 5D-CAP as internal standard. At these levels, trueness ranged between 98.7 and 102.0% and within-laboratory reproducibility was lower than 6.2%, expressed as relative standard deviation. The limit of decision (CCα) was 0.07 μg kg−1 and detection capability (CCβ) was 0.10 μg kg−1.

Sulfonamides represent a wide range of synthetic compounds commonly used in veterinary therapy for the treatment of several bacterial and protozoan infections in cattle, swine and poultry. Trimethoprim is another antibacterial agent mainly used in fish culture and often combined with sulfonamides in commercial preparations. Residues of these drugs in foodstuffs are of concern because of their potential carcinogenic character. Consequently, the European Union (EU) and United States Food and Drug Administration set maximum residue limits for both sulfonamides (100 microg/kg either as a single molecule or as a sum of all detected compounds within the class) and trimethoprim (TMP) (50 microg and 100 microg/kg, according to the matrix) in chicken, fish muscle and eggs.On the other hand, these limits have made of concern the development of confirmatory methods for the analysis of these molecules. LC-MS/MS technique, in particular, resulted fit for the detection of these medium polarity compounds. An effective multi-residue method is presented for the simultaneous determination of certain sulfonamides (sulfadiazine, sulfathiazole, sulfamerazine, sulfamethazine, sulfamethoxypyridazine, sulfamethoxazole, sulfadimethoxine and sulfaquinoxaline) and TMP in products of animal origin (chicken muscle, fish muscle and eggs) by liquid chromatographymass spectrometry/mass spectrometry (LC-MS/MS) at levels in compliance with the legislation in force. The drugs were extracted with a mixture of dichloromethane/acetone (1:1, v/v) and clean-up was carried out by solid phase extraction (SPE) on a sulfonic acid column after addition of acetic acid to the extract, so as to allow for ionexchange. Sulfonamides and TMP were then eluted from the SPE column using a solution of ammonia in methanol. The chromatographic separation was performed on a C18 column by using a mobile phase of methanol/5 mM aqueous ammonium acetate and 0.1% formic acid in gradient, and the LC-MS/MS analysis was performed in a triplequadrupole mass spectrometer equipped with a TurboIonSpray source and operated in positive ion mode. The multiple reaction monitoring (MRM) approach was adopted for the identification and quantification of the molecules of concern and was applied by selecting three specific diagnostic ions (one precursor ion and two product ions) for each analyte, so as to meet the criteria set by the EU both for the minimum required number of identification points and for the ion intensity ratio tolerances. Calculated detection limits for sulfonamides (signal/noise ratio 3:1) ranged from 0.1 microg to 1.7 microg/kg, whereas the recovery rates varied between 69.5% and 94.2% throughout the different compounds and matrices. The corresponding values for TMP ranged from 0.2 microg to 0.4 microg/kg and between 51.9% and 52.8%, according to the matrix. The easy sample preparation procedure and the specific and selective mass spectrometric detection make the present method reliable and suitable for the unambiguous identification and quantitation of the analytes taken into account in chicken, fish muscle and eggs. Moreover, method application has successfully extended to other sulfonamides, such as sulfaguanidine, sulfapyridine, sulfamoxole and sulfamethizole.

Many people who work in laboratory rodent breeding facilities believe that disrupting certain sensitive rodent lines will result in increased breeding failures and loss of newborn pups. To evaluate this hypothesis, the authors assessed the effect of cage-change frequency on the breeding performances of a mouse strain (C57BL/6NTac) and a rat stock (NTac:NIH-Whn) that were thought to be sensitive to disruption. As per recommendations in the Guide for the Care and Use of Laboratory Animals, personnel changed one half of the breeding cages weekly, regardless of the presence of newborn pups. The other breeding cages were also changed weekly, unless newborn pups were present, in which case the cages were not changed until the following week. The authors assessed breeding performance by calculating the production efficiency index (the total number of pups that survived to weaning divided by the total number of actively breeding females). Breeding performance did not differ significantly between rodents whose cages were changed weekly and those whose pups were not disturbed.