2,002 research outputs found
Full Characterization of the First 1 Inch Industrial Prototype of a New Concept Photodetector
The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an original design for an
innovative light detector we proposed with the aim to create new scientific
instrumentation for industrial applications and physics research. The idea
behind this device is to replace the classical dynode chain of a
photomultiplier tube with a silicon photomultiplier, the latter acting as an
electron detector and amplifier. The VSiPMT offers very attractive features and
unprecedented performance, definitely superior to every other photodetector
with comparable sensitive surface, such as: negligible power cosumption,
excellent photon counting, easy low-voltage-based stabilization and very good
time performance. After the feasibility test of the idea, Hamamatsu Photonics
realized for our research group two VSiPMT industrial prototypes, that have
been fully characterized. The results of the full characterization of the
1-inch industrial prototype are presented in this work.Comment: 11 pages, 14 figure
Longitudinal tear protein changes correlate with ocular chronic gvhd development in allogeneic hematopoietic stem cell transplant patients
Ocular graft-versus-host disease (oGVHD) is a manifestation of chronic GVHD, frequently occurring in patients after allogeneic hematopoietic stem cell transplant (HSCT). We analyzed tear protein changes before and after allogeneic HSCT, and correlated their levels with the oGVHD development. This retrospective study included 102 patients, and data were recorded before the conditioning treatment, and after 3 to 6 months postoperatively. Tear protein analysis was performed with the Agilent-2100 Bioanalyzer on individual tears sampled by aspiration. Total protein (TP), Lysozyme-C (LYS-C), Lactoferrin (LACTO), Lipocalin-1 (LIPOC-1), Transferrin (TRANSF), Albumin (ALB), and Zinc-alpha-2-glycoprotein (ZAG-2) levels were retrieved and statistically analyzed. Following HSCT forty-three patients developed oGVHD. TP, LACTO, LYS-C, and ZAG-2 levels significantly decreased post-HSCT as compared to pre HSCT levels. In univariate analysis, TP, LACTO, and ZAG-2 decrease was associated with an increased development of oGVHD (OR = 4.49; 95% CI, 1.9 to 10.5; p < 0.001; OR = 3.08; 95% CI 1.3 to 7.6; p = 0.01; OR = 11.1; 95% CI 2.7 to 46.6; p < 0.001, respectively). TRANSF post-HSCT levels significantly increased (OR 15.7; 95% CI, 4.1 to 52.2; p = 0.0001). No pre-post-HSCT changes were shown in ALB and LIPOC-1 levels. Data suggest that TP content, LACTO, TRANSF, and ZAG-2 pre-post changes might be significant predictors of oGVHD development
COLON MICROBIAL COMPOSITION IS CORRELATED WITH THE SEVERITY OF COLITIS INDUCED BY 2,4,6-TRINITROBENZESULFONIC ACID IN MICE.
The objective of this study was to evaluate the changes in some bacterial species of colonic microbiota, the clinical signs and the intestinal changes in mice with 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced colitis. CD-1 male mice were randomly divided into three groups and inoculated intrarectally with saline ethanol or TNBS solutions. ethanol and TNBS treatments induced weight loss accompained by mild and severe inflammation of the colon mucosa, respectively. however, TNBS-treated mice displayed significant differences compared to the saline group in terms of disease activity index and histological scoring. Both ethanol and TNBS groups showed an increased prevalence of escherichia coli and Clostridium supp., a decrease in lactobacilli and Bifidobacteria counts, as well as changes in the relative proportions of bacteria in the colon. The results confirm the validity of TNBS treatment to study the mechanism involved in the pathogenesis and progression of inflammatory bowel diseases (IBD) in CD-1 mice. Gut microbiota may become a diagnostic biomarker with therapeutic potential for IBD in the future
Uprighting impacted mandibular second molar using a skeletal anchorage: a case report
The aim of this case report is to present an innovative combined orthodontic-surgical technique to disimpact mandibular second molar (MM2) using an orthodontic miniscrew and an elastic chain. The impact on the Oral health-related quality of life (OHRQoL) was also evaluated. Using the present techinique, it is possible to expose the impacted tooth, insert a self-drilling miniscrew in the retromolar area, and remove the bud of third mandibular molar. At the same time the orthodontic force is applied with the use of an elastomeric chain that connects the head of miniscrew and vestibular and oral buttons bonded on MM2. A close traction is performed for the whole treatment time without the reactivation of the elastic force. The use of skeletal anchorage allowed the disimpaction of impacted MM2 in a short treatment time (about three months) avoiding the typical biomechanical side effects of traditional orthodontic appliance and increasing the effectiveness of the treatment. Further studies are necessary to evaluate the real advantages and disadvantages of this combined orthodontic-surgical approach
Comparision of profile macro-estethic perception among orthodontists, dentistry students, orthodontic patients and surgical orthodontic patients
Background: The patient's needs should guide the orthodontist in choosing the most appropriate therapy. The purpose of the present survey was to compare the esthetic perception of the facial profile by orthodontists (O), dentistry students (DS), orthodontic patients (OP) and surgical-orthodontic patients (SOP) and to evaluate the influence of gender, age and level of study. Material and Methods: A facial profile photograph of a young female was taken and twelve modified images were made, altering the position of the jaws in protrusion and in retrusion. Two hundred caucasian examiners, divided into four groups (O, DS, OP, SOP), were selected. Each examiner was asked to complete the questionnaire with an approval rating from 1 to 10. An ordinary least square OLS model was applied. Significant levels were set at P ≤ 0.05. Results: All examiners considered a straight profile or a slight retrusion of the maxilla as the most attractive profile. Slight discrepancies (up to 2 mm) in jaw protrusion were barely perceived by patients. Mandibular retrusion (2 and 4 mm) was one of the least appreciated condition by all examiners. Surgical-orthodontic patients assigned lower ratings compared to orthodontic patients. Female subjects assigned lower ratings than males. Patients with secondary school education assigned higher statistically significant values compared to other levels of study. The lowest values were attributed by the sample of age > = 17 years. Conclusions: The choice of the most appropriate therapy is based not only on a correct diagnosis, but on the evaluation of esthetic and psychological aspects
A small slug from a tropical greenhouse reveals a new rathouisiid lineage with triaulic tritrematic genitalia (Gastropoda: Systellommatophora)
A small slug found in the tropical greenhouse of the Science Museum (MUSE) of Trento (Italy) turned out to be a species of the little-known systellommatophoran family Rathouisiidae. We undertook detailed comparative anatomical and molecular studies using specimens of the MUSE slug, Rathouisia sinensis, and sequences of other systellommatophoran species deposited in GenBank to conduct a systematic and phylogenetic assessment. Analysis of the genitalia of the MUSE slug and R. sinensis revealed an unusual triaulic tritrematic structure: two separate female ducts – one for egg release (oviduct), the other for intake of allosperm (vagina) – and a separate male duct for autosperm release. Analysis of the nucleotide sequences of several mitochondrial (COI, 16S rDNA) and nuclear (18S rDNA, ITS2 flanked by 5.8S and 28S rDNA fragments, H3) gene fragments supported assignation of the MUSE slug to Rathouisiidae, but also its distinction from the other rathouisiid genera Atopos, Granulilimax, Rathouisia and an undescribed genus from the Ryukyu Islands (Japan). Therefore, we decided to describe the MUSE slug as a new species in a new genus: Barkeriella museensis gen. et sp. nov. The species is certainly an alien introduced into the tropical greenhouse of MUSE, but its origin is unknown and calls for further investigation. © 2022 The Linnean Society of London
Recent development on the realization of a 1-inch VSiPMT prototype
The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design for a revolutionary hybrid photodetector. The idea, born with the purpose to use a SiPM for large detection volumes, consists in replacing the classical dynode chain with a SiPM. In this configuration, we match the large sensitive area of a photocathode with the performances of the SiPM technology, which therefore acts like an electron detector and so like a current amplifier. The excellent photon counting capability, fast response, low power consumption and great stability are among the most attractive features of the VSiPMT. In order to realize such a device we first studied the feasibility of this detector both from theoretical and experimental point of view, by implementing a Geant4-based simulation and studying the response of a special non-windowed MPPC by Hamamatsu with an electron beam. Thanks to this result Hamamatsu realized two VSiPMT industrial prototypes with a photocathode of 3mm diameter. We present the progress on the realization of a 1-inch prototype and the preliminary tests we are performing on it
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