Quad-module characterization with the MALTA monolithic pixel chip Dachs, F.; Zoubir, A.M.; Sharma, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2024, Letnik:
1064
Journal Article
Recenzirano
The MALTA silicon pixel detector combines a depleted monolithic active pixel sensor (DMAPS) with a fully asynchronous front-end and readout. It features a high granularity pixel matrix with a 36.4 μm ...symmetric pixel pitch, low power consumption of <1 μW/pixel and low material budget with detector thicknesses as little as 50 μm. It achieves a radiation hardness to 100MRad TID and more than 1 × 10E15 1 MeV neq/cm2 with a time resolution of <2 ns (Pernegger et al., 2023).
In order to cover large sensitive areas efficiently with a minimum of power and data connections the development of modules, comprising of up to 4 MALTA detectors, is studied.
This contribution presents the beam test performance of parallel and serial powered MALTA 4-chip modules in an effort to characterize the sensor’s chip-to-chip data and power transmission and prepare the production of a first prototype of an ultra-light weight 4-chip module on a flexible circuit with next generation MALTA2 sensors.
Background Esophageal self-expandable stents (SESs) effectively treat strictures and leaks but may be complicated by a stent-associated esophagorespiratory fistula (SERF). Little is known about ...SERFs. Objective To determine the incidence, morbidity, mortality, and risk factors for SERF. Design Retrospective case-control study. Setting Single referral center. Patients All adults undergoing esophageal SES placement during a 10-year period. Intervention Stent placement. Main Outcome Measurements Occurrence of SERF, morbidity, and mortality. Results A total of 16 of 397 (4.0%) patients developed SERF at a median of 5 months after stent placement (range 0.4-53 months) including 6 of 94 (6%), 10 of 71 (14%), and 0 of 232 (0%) of those with lesions in the proximal, middle, and distal esophagus, respectively (overall P < .001). SERF occurred in 10% of those with proximal and mid-esophageal lesions, including 14% with benign strictures, 9% with malignant strictures, and none with other indications for SES placement ( P = .27). The risk was highest (18%) in patients with benign anastomotic strictures. Risk factors for development of SERF included a higher Charlson comorbidity index score (odds ratio OR 1.47 for every 1-point increase; P = .04) and history of radiation therapy (OR 9.41; P = .03). Morbidity associated with SERF included need for lifelong feeding tubes in 11 of 22 (50%) and/or tracheostomy or mechanical ventilation in 5 of 22 (23%). Median survival after diagnosis was 4.5 months (range 0.35-67), and 7 patients survived less than 30 days. Limitations Retrospective design, limited statistical power. Conclusion SERF is a morbid complication of SES placement for strictures of the proximal and mid-esophagus. The dominant risk factors for development of SERF are prior radiation therapy and comorbidity score.
Endoscopic sleeve gastroplasty (ESG) is an endolumenal, organ-sparing therapy for obesity, with wide global adoption. We aimed to explore the efficacy and safety of ESG with lifestyle modifications ...compared with lifestyle modifications alone.
We conducted a randomised clinical trial at nine US centres, enrolling individuals aged 21–65 years with class 1 or class 2 obesity and who agreed to comply with lifelong dietary restrictions. Participants were randomly assigned (1:1·5; with stratified permuted blocks) to ESG with lifestyle modifications (ESG group) or lifestyle modifications alone (control group), with potential retightening or crossover to ESG, respectively, at 52 weeks. Lifestyle modifications included a low-calorie diet and physical activity. Participants in the primary ESG group were followed up for 104 weeks. The primary endpoint at 52 weeks was the percentage of excess weight loss (EWL), with excess weight being that over the ideal weight for a BMI of 25 kg/m2. Secondary endpoints included change in metabolic comorbidities between the groups. We used multiple imputed intention-to-treat analyses with mixed-effects models. Our analyses were done on a per-protocol basis and a modified intention-to-treat basis. The safety population was defined as all participants who underwent ESG (both primary and crossover ESG) up to 52 weeks.
Between Dec 20, 2017, and June 14, 2019, 209 participants were randomly assigned to ESG (n=85) or to control (n=124). At 52 weeks, the primary endpoint of mean percentage of EWL was 49·2% (SD 32·0) for the ESG group and 3·2% (18·6) for the control group (p<0·0001). Mean percentage of total bodyweight loss was 13·6% (8·0) for the ESG group and 0·8% (5·0) for the control group (p<0·0001), and 59 (77%) of 77 participants in the ESG group reached 25% or more of EWL at 52 weeks compared with 13 (12%) of 110 in the control group (p<0·0001). At 52 weeks, 41 (80%) of 51 participants in the ESG group had an improvement in one or more metabolic comorbidities, whereas six (12%) worsened, compared with the control group in which 28 (45%) of 62 participants had similar improvement, whereas 31 (50%) worsened. At 104 weeks, 41 (68%) of 60 participants in the ESG group maintained 25% or more of EWL. ESG-related serious adverse events occurred in three (2%) of 131 participants, without mortality or need for intensive care or surgery.
ESG is a safe intervention that resulted in significant weight loss, maintained at 104 weeks, with important improvements in metabolic comorbidities. ESG should be considered as a synergistic weight loss intervention for patients with class 1 or class 2 obesity. This trial is registered with ClinicalTrials.gov, NCT03406975.
Apollo Endosurgery, Mayo Clinic.
The double-differential production cross-section of positive pions, , measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with ...a thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75 GeV/c≤pπ≤ 6.5 GeV/c and 30 mrad≤θπ≤ 210 mrad in the laboratory frame.
An assessment of radiotherapy dosimeters based on CVD grown diamond Ramkumar, S.; Buttar, C.M.; Conway, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2001, Letnik:
460, Številka:
2
Journal Article
Recenzirano
Diamond is potentially a very suitable material for use as a dosimeter for radiotherapy. Its radiation hardness, the near tissue equivalence and chemical inertness are some of the characteristics of ...diamond, which make it well suited for its application as a dosimeter. Recent advances in the synthesis of diamond by chemical vapour deposition (CVD) technology have resulted in the improvement in the quality of material and increased its suitability for radiotherapy applications. We report in this paper, the response of prototype dosimeters based on two different types (CVD1 and CVD2) of CVD diamond to X-rays. The diamond devices were assessed for sensitivity, dependence of response on dose and dose rate, and compared with a Scanditronix silicon photon diode and a PTW natural diamond dosimeter. The diamond devices of CVD1 type showed an initial increase in response with dose, which saturates after ≈6
Gy. The diamond devices of CVD2 type had a response at low fields (<1162.8
V/cm) that was linear with dose and dose rate. At high fields (>1162.8
V/cm), the CVD2-type devices showed polarisation and dose-rate dependence. The sensitivity of the CVD diamond devices varied between 82 and 1300
nC/Gy depending upon the sample type and the applied voltage. The sensitivity of CVD diamond devices was significantly higher than that of natural diamond and silicon dosimeters. The results suggest that CVD diamond devices can be fabricated for successful use in radiotherapy applications.
The high-luminosity LHC will present significant challenges for tracking systems. ATLAS is preparing to upgrade the entire tracking system, which will include a significantly larger pixel detector. ...This paper reports on the development of large area planar detectors for the outer pixel layers and the pixel endcaps. Large area sensors have been fabricated and mounted onto 4 FE-I4 readout ASICs, the so-called quad-modules, and their performance evaluated in the laboratory and testbeam. Results from characterisation of sensors prior to assembly, experience with module assembly, including bump-bonding and results from laboratory and testbeam studies are presented.
The HARP detector at the CERN PS Catanesi, M.G.; Muciaccia, M.T.; Radicioni, E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2007, Letnik:
571, Številka:
3
Journal Article
Recenzirano
HARP is a high-statistics, large solid angle experiment to measure hadron production using proton and pion beams with momenta between 1.5 and 15
GeV/
c
impinging on many different solid and liquid ...targets from low to high
Z. The experiment, located in the T9 beam of the CERN PS, took data in 2001 and 2002. For the measurement of momenta of produced particles and for the identification of particle types, the experiment includes a large-angle spectrometer, based on a Time Projection Chamber and a system of Resistive Plate Chambers, and a forward spectrometer equipped with a set of large drift chambers, a threshold Cherenkov detector, a time-of-flight wall and an electromagnetic calorimeter. The large angle system uses a solenoidal magnet, while the forward spectrometer is based on a dipole magnet. Redundancy in particle identification has been sought, to enable the cross-calibration of efficiencies and to obtain a few percent overall accuracy in the cross-section measurements. Detector construction, operation and initial physics performances are reported. In addition, the full chain for data recording and analysis, from trigger to the software framework, is described.
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