Lithium ion-induced damage in silicon detectors

Silicon diodes processed by CNM on standard and oxygenated silicon substrates have been irradiated by 58 MeV lithium ions. The radiation-induced effects are very similar to the one observed after proton irradiation: substrate space charge sign inversion (SCSI), lower increase of the effective substrate doping concentration after SCSI for the oxygenated devices. The experimental radiation hardness factor has been determined to be 45.01, within 8.2% with the expected value. These results suggest that 58 MeV Li ions are a suitable radiation source for radiation hardness studies by ions heavier than protons for the future very high luminosity hadron colliders

Montgomery salivary bypass tube in head and neck cancer: the experience of our otolaryngology clinic

Introduction: One of the most common complications in the immediate and late postoperative period following total laryngectomy or pharyngolaryngectomy is pharyngocutaneous fistulae (PCF) formation and pharyngoesophageal stenosis (PES), causing significant mortality and morbidity. Since 1978, Montgomery salivary bypass tube (MSBT) has been used to reduce the incidence of PCF and PES. The aim of this retrospective study was to analyze the outcomes of using MSBT both as a tool to prevent PCF and PES and to treat these complications in the postoperative period. Methods: Between January 2013 and December 2019, we inserted 109 MSBT in 87 patients with laryngeal/hypopharyngeal cancer treated in the Unit of Otolaryngology of our University Hospital. Results: Sixty (86.9%) patients healed from complications with primary and secondary placement of MSBT. Seven patients presented a persistence of PCF and 2 presented a recurrence of PES. Secondary placement of MSBT allowed treating successfully 15 (83%) of 18 patients. Only 3 of them presented a PCF at the end of the follow-up period. Conclusion: According to our experience, the MSBT is an affordable, easy to apply and well-tolerated tool. Although it is generally used for PCF treatment, it can also be used intraoperatively for PCF and PES prevention

Catching and monitoring clinical innovation through performance indicators. The case of the breast-conserving surgery indicator.

Background: The evolution in the surgical and diagnostic procedures, the attention to women’s preferences, the case mix, and di erences in professional practices may lead to a variability in the quality of breast cancer clinical pathway. To catch and manage this variability it is important to use valid measures. The aim of this paper is to examine the concurrent validity of the breast-conserving surgery (BCS) indicator and to provide evidence to guide the quality improvement process. Methods: The BCS indicator was calculated using hospital discharge records (HDRs) and was validated against surgi- cal registry (SR) data in a random sample of 336 women undergoing breast cancer surgery in 2012 in two Tuscan teaching hospitals. The concurrent validity of BCS was examined by cross-tabulating patients using the ICD-9 CM codes for breast surgery obtained from the two data sources. Results: The analysis, carried out involving breast cancer professionals, highlighted that the large majority of inter- ventions coded as “mastectomies” in HDRs are in fact reconstructing procedures, including nipple-sparing, skin- sparing and skin-reducing mastectomies in SR. These results led us to re ne the old algorithm, that calculates the proportion of breast-conserving surgery over the total number of breast interventions, and reclassify breast cancer surgical procedures into three categories: conservative, reconstructive and traditional mastectomy. Based on this new classi cation algorithm, the percentages of (I) reconstructive interventions were 16% at Florence TH and 38.3% at Pisa TH; (II) breast-conserving interventions were respectively 72.8 and 52.1%; and (III) mastectomies 11.2 and 9.6%. After adjusting for age in a logistic regression model, the percentages of reconstructive interventions at Florence and Pisa were respectively 22 and 34% and those of breast-conserving interventions 63 and 53%. Conclusions: Our results indicate that breast cancer care indicators should be re ned by distinguishing reconstruc- tive procedures (nipple/skin-sparing surgery with implant or breast tissue expander insertion) from traditional mas- tectomy. The involvement of breast care professionals in the choice of indicators proved to be crucial to capture the up-to-date breast cancer surgical practice and inform the quality improvement process. Keywords: Performance indicators, Breast cancer, Breast conserving surgery, Healthcare quality, Professional involvemen

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Microstrip detectors and front-end electronics: performance, spice simulations and dielectric reliability issues

Dottorato di ricerca in ingegneria elettronica e delle telecomunicazioni. 11. ciclo. Coordinatore S. Pupolin. Tutore A. PaccagnellaConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Breakdown of coupling dielectrics for Si microstrip detectors

Double-layer coupling dielectrics for AC-coupled Si microstrip detectors have been electrically characterized in order to determine their performance in a radiation-harsh environment, with a focus on the dielectric breakdown. Two different dielectric technologies have been investigated: SIO2/TEOS and SiO2/Si3N4. Dielectrics have been tested by using a negative gate voltage ramp of 0.2 MV/(cm.s). The metal/insulator/Si I-V characteristics show different behaviours depending on the technology. The extrapolated values of the breakdown field for unirradiated devices are significantly higher for SiO2/Si3N4 dielectrics, but the data dispersion is lower for SiO2/TEOS devices. No significant variation of the breakdown field has been measured after a 10 Mrad (Si) gamma irradiation for SiO2/Si3N4 dielectrics. Finally, the SiO2/Si3N4 DC conduction is enhanced if a positive gate voltage ramp is applied with respect to the negative one, due to the asymmetric conduction of the double-layer dielectric

Degradation of electron irradiated MOS capacitors

We have investigated the degradation of MOS structure due to high energy electron irradiation as a function of radiation dose and gate bias applied during the irradiation. Devices have been characterized by current-voltage measurements, in order to study charge accumulation also at the gate interface. Three types of oxide charge have been observed: the unstable positive charge, due to trapped holes induced by the electron irradiation; the negative charge in the oxide bulk, deriving from capture of electrons injected during electrical measurements in radiation generated traps; and border traps, at both oxide interfaces

MOSFET parameter degradation after Fowler\u2013Nordheim injection stress

We have investigated the degradation of tunnel oxides due to Fowler-Nordheim electron injection from polysilicon gate. Tested devices are n-MOSFET normally used for Flash EPROM applications with four different technologies for the tunnel oxide layer. Stresses have been performed at different source and drain bias conditions for a total injected charge up to 1 C/cm(2). The oxide characteristics and degradation have been determined comparing the MOSFET threshold voltage and transconductance peak for as received devices and after each stress step

SPICE evaluation of the S/N ratio for Si microstrip detectors

none5SPICE simulations of AC-coupled single-sided Si microstrip detectors connected to the Pre-Shape 32 read-out chip have been performed in order to determine the geometrical characteristics (i.e. the strip pitch p and width w) which maximize the signal-to-noise ratio at room temperature. All the resistive and capacitive elements of the detector have been determined as a function of the w/p ratio, by considering experimental and simulated data available in the literature. The SPICE model takes into account all the main noise sources in the detector and read-out electronics. The minimum ionizing particle current signal shape characteristics have been introduced in the simulations. Two read-out configurations (every strip or every second strip) have been investigated for 6.4 cm and 12.8 cm long detectors. Finally, general guidelines in the detector design have been proposed starting from the simulation results.noneA. Candelori;A. Paccagnella;F. Nardi;N. Bacchetta;D. BiselloCandelori, Andrea; Paccagnella, Alessandro; F., Nardi; N., Bacchetta; Bisello, Dari