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1.
Foods ; 12(24)2023 Dec 12.
Article in English | MEDLINE | ID: mdl-38137252

ABSTRACT

Intensive agricultural practices, such as pesticides use, may negatively affect bee health and hive products. Glyphosate is one of the most widely used polar pesticides applied in crops for weed control. In this study, honey samples, collected from beekeeping farms located in the Lombardy and Emilia-Romagna regions in Italy in the framework of regional monitoring plans activated from 2020 to 2022, were analyzed for the presence of residues of polar pesticides. The analytical method based on ion chromatography coupled to high-resolution mass spectrometry was applied to quantify glyphosate, glufosinate, ethephon, fosetyl aluminum, and their related metabolites. Residues of glyphosate were detected in around 28% of analyzed honey samples. Observations on the distribution of the honey-production-site locations suggest that honey samples originating from the provinces within the Lombardy region, where the agricultural sector is highly developed, were more affected by glyphosate contamination than the samples collected from the areas with low agricultural activity, where no glyphosate residues were detected over the three years of the monitoring program.

2.
Front Vet Sci ; 9: 853707, 2022.
Article in English | MEDLINE | ID: mdl-35498733

ABSTRACT

American Foulbrood (AFB) is a contagious and severe brood disease of honey bees caused by the spore-forming bacterium Paenibacillus larvae. The identification of honey bee colonies infected by P. larvae is crucial for the effective control of AFB. We studied the possibility of identifying the infection levels by P. larvae in honey bee colonies through the examination of powdered sugar samples collected in the hives. The powdered sugar was dusted on the top bars of honeycombs and collected from a sheet paper placed at the bottom of the hive. Three groups of honey bee colonies were examined: Group A1- colonies with clinical symptoms of AFB (n = 11); Group A2 - asymptomatic colonies located in apiaries with colonies showing symptoms of AFB (n = 59); Group B - asymptomatic colonies located in apiaries without cases of the disease (n = 49). The results showed that there was a significant difference in spore counting between Groups and that the spore load in sugar samples was always consistent with the clinical conditions of the colonies and with their belonging to AFB-affected apiaries or not. Based on the obtained results the cultural examination of powdered sugar samples collected from hives could be an effective tool for the quantitative non-destructive assessment of P. larvae infections in honey bee colonies.

3.
Rev Sci Instrum ; 88(3): 034502, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28372423

ABSTRACT

GINGERino is a large frame laser gyroscope investigating the ground motion in the most inner part of the underground international laboratory of the Gran Sasso, in central Italy. It consists of a square ring laser with a 3.6 m side. Several days of continuous measurements have been collected, with the apparatus running unattended. The power spectral density in the seismic bandwidth is at the level of 10-10 (rad/s)/Hz. A maximum resolution of 30 prad/s is obtained with an integration time of few hundred seconds. The ring laser routinely detects seismic rotations induced by both regional earthquakes and teleseisms. A broadband seismic station is installed on the same structure of the gyroscope. First analysis of the correlation between the rotational and the translational signal is presented.

4.
EJNMMI Phys ; 4(1): 11, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28211032

ABSTRACT

BACKGROUND: Monolithic scintillators read out by arrays of photodetectors represent a promising solution to obtain high spatial resolution and the depth of interaction (DOI) of the annihilation photon. We have recently investigated a detector geometry composed of a monolithic scintillator readout on two sides by silicon photomultiplier (SiPM) arrays, and we have proposed two parameters for the DOI determination: the difference in the number of triggered SiPMs on the two sides of the detector and the difference in the maximum collected signal on a single SiPM on each side. This work is focused on the DOI calibration and on the determination of the capability of our detector. For the DOI calibration, we studied a method which can be implemented also in detectors mounted in a full PET scanner. We used a PET detector module composed of a monolithic 20 × 20 × 10 mm3 LYSO scintillator crystal coupled on two opposite faces to two arrays of SiPMs. On each side, the scintillator was coupled to 6 × 6 SiPMs. In this paper, the two parameters previously proposed for the DOI determination were calibrated with two different methods. The first used a lateral scan of the detector with a collimated 511 keV pencil beam at steps of 0.5 mm to study the detector DOI capability, while the second used the background radiation of the 176Lu in the scintillator. The DOI determination capability was tested on different regions of the detector using each parameter and the combination of the two. RESULTS: With both parameters for the DOI determination, in the lateral scan, the bias between the mean reconstructed DOI and the real beam position was lower than 0.3 mm, and the DOI distribution had a standard deviation of about 1.5 mm. When using the calibration with the radioactivity of the LYSO, the mean bias increased of about 0.2 mm but with no degradation of the standard deviation of the DOI distribution. CONCLUSIONS: The two parameters allow to achieve a DOI resolution comparable with the state of the art, giving a continuous information about the three-dimensional interaction position of the scintillation. These results were obtained by using simple estimators and a detector scalable to a whole PET system. The DOI calibration obtained using lutetium natural radioactivity gives results comparable to the other standard method but appears more readily applicable to detectors mounted in a full PET scanner.

5.
Article in English | MEDLINE | ID: mdl-20211779

ABSTRACT

G-Pisa is an experiment investigating the possibility of operating a high-sensitivity laser gyroscope with area less than 1 m2 for improving the performances of the mirrors suspensions of the gravitational wave antenna Virgo. The experimental set-up consists of a He-Ne ring laser with a 4-mirror square cavity. The laser is pumped by an RF discharge where the RF oscillator includes the laser plasma to reach a better stability. The contrast of the Sagnac fringes is typically above 50% and a stable regime has been reached with the laser operating in either single mode or multimode. The effect of hydrogen contamination on the laser was also checked. A low-frequency sensitivity, below 1 Hz, in the range of 10(-8)(rad/s)/square root(Hz) has been measured.

6.
Ann Vasc Surg ; 21(3): 346-51, 2007 May.
Article in English | MEDLINE | ID: mdl-17419005

ABSTRACT

This study reports the development of a new open external vascular stent: the lock stent device (LSD). It enables a novel end-to-end sleeve anastomotic technique, named locked anastomosis (LA). The LA technique consists of inserting a graft sleeve within an artery, secured in place by an internal stent and an external LSD. The internal stent, graft, vessel wall, and LSD are fastened together with single sutures. The LSD placement does not require a complete transection of the vessel wall as it can be enlarged and then relaxed to clasp the vessel neck. The tensile strength of the LA technique was accurately measured ex vivo and its stability successfully tested in vivo by acute pressure peak tests and mid-term survival studies. Ex vivo, the ratio between the tensile strength of the LA technique with two, three, and six stitches and that of hand-sewn anastomoses was 0.41 +/- 0.02, 0.59 +/- 0.17, and 1.03 +/- 0.04. In vivo, LA anastomoses tolerated marked increases in blood pressure (peak systolic pressure 195-230 mm Hg) for periods of 15-25 min without leakage. Five pigs survived 10 weeks with abdominal aorto-aortic bypass performed according to the LA technique with three stitches. Aortograms showed no narrowing or thromboses, and histological findings confirm uniform flattening of the aortic wall at the anastomosis, with proliferating neointima and uniformly hypotrophic media. Minimal changes were observed in the adventitia.


Subject(s)
Vascular Surgical Procedures/methods , Anastomosis, Surgical/instrumentation , Anastomosis, Surgical/methods , Animals , Aorta, Abdominal/pathology , Aorta, Abdominal/physiopathology , Aorta, Abdominal/surgery , Aorta, Thoracic/pathology , Aorta, Thoracic/physiopathology , Aorta, Thoracic/surgery , Blood Pressure , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis Implantation/methods , Cattle , Disease Models, Animal , Elasticity , Equipment Safety , Hypertension/physiopathology , Prosthesis Design , Sheep , Stents , Swine , Tensile Strength , Time Factors , Tunica Intima/pathology , Tunica Intima/physiopathology , Tunica Intima/surgery , Tunica Media/pathology , Tunica Media/physiopathology , Tunica Media/surgery , Vascular Surgical Procedures/instrumentation
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