High-energy physics experiments in space

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Radiation-induced edge effects in deep submicron CMOS transistors

The study of the TID response of transistors and isolation test structures in a 130 nm commercial CMOS technology has demonstrated its increased radiation tolerance with respect to older technology nodes. While the thin gate oxide of the transistors is extremely tolerant to dose, charge trapping at the edge of the transistor still leads to leakage currents and, for the narrow channel transistors, to significant threshold voltage shift-an effect that we call Radiation Induced Narrow Channel Effect (RINCE)

Radiation damage and annealing in 1310 nm InGaAsP/InP lasers for the CMS tracker

Radiation damage in 1310 nm InGaAsP/InP multi-quantum-well lasers caused by 0.8 MeV neutrons is compared with the damage from other radiation sources, in terms of the increase in laser threshold current. The annealing behavior is then presented both in terms of both temperature and forward-bias current dependence. The annealing can be described by a model where radiation induced defects have a uniform distribution of activation energies for annealing. This model can then be used to predict the long-term damage expected for lasers operating inside the CMS tracker. (19 refs)

Time stability of asymmetric Fabry-Perot modulator based analog lightwave links

Lightwave links for analog signal transfer are being developed and evaluated for application in high-density interconnects. The reflective links are based on compact electro-optic intensity modulators connected by ribbons of single-mode fibres to remotely located transceivers (lasers and photoreceivers) and read-out electronics. For long-term characterization, four Asymmetric Fabry-Perot Modulator (AFPM) prototypes were continuously operated and monitored over a period of eight monthes. The collected data allow evaluation of the system time stability and simulation of the possible recalibration procedures. The recalibration requirements to achieve the desirable accuracy and reliability are inferred statistically

Optical links for the CMS tracker

The development phase of the optical data transfer system for the CMS tracker is nearing completion. This paper focuses on three types of validation tests carried out by CERN on Commercial-Off-The-Shelf electro-optic devices: functionality tests, environmental tests and reliability tests. The project status and the preparation for production are also reviewed. 1

Pre-Production and Quality Assurance of the Mu2e Calorimeter Silicon Photomultipliers

The Mu2e electromagnetic calorimeter has to provide precise information on energy, time and position for $\sim$100 MeV electrons. It is composed of 1348 un-doped CsI crystals, each coupled to two large area Silicon Photomultipliers (SiPMs). A modular and custom SiPM layout consisting of a 3$\times$2 array of 6$\times$6 mm$^2$ UV-extended monolithic SiPMs has been developed to fulfill the Mu2e calorimeter requirements and a pre-production of 150 prototypes has been procured by three international firms (Hamamatsu, SensL and Advansid). A detailed quality assurance process has been carried out on this first batch of photosensors: the breakdown voltage, the gain, the quenching time, the dark current and the Photon Detection Efficiency (PDE) have been determined for each monolithic cell of each SiPMs array. One sample for each vendor has been exposed to a neutron fluency up to $\sim$8.5~$\times$~10$^{11}$ 1 MeV (Si) eq. n/cm$^{2}$ and a linear increase of the dark current up to tens of mA has been observed. Others 5 samples for each vendor have undergone an accelerated aging in order to verify a Mean Time To Failure (MTTF) higher than $\sim$10$^{6}$ hours.Comment: NDIP 2017 - New Developments In Photodetection, 3-7 July 2017, Tours (France

Adipose-derived stem/stromal cells in kidney transplantation: Status quo and future perspectives

Kidney transplantation (KT) is the gold standard treatment of end-stage renal disease. Despite progressive advances in organ preservation, surgical technique, intensive care, and immunosuppression, long-term allograft survival has not significantly improved. Among the many peri-operative complications that can jeopardize transplant outcomes, ischemia-reperfusion injury (IRI) deserves special consideration as it is associated with delayed graft function, acute rejection, and premature transplant loss. Over the years, several strategies have been proposed to mitigate the impact of IRI and favor tolerance, with rather disappointing results. There is mounting evidence that adipose stem/stromal cells (ASCs) possess specific characteristics that could help prevent, reduce, or reverse IRI. Immunomodulating and tolerogenic properties have also been suggested, thus leading to the development of ASC-based prophylactic and therapeutic strategies in pre-clinical and clinical models of renal IRI and allograft rejection. ASCs are copious, easy to harvest, and readily expandable in culture. Furthermore, ASCs can secrete extracellular vesicles (EV) which may act as powerful mediators of tissue repair and tolerance. In the present review, we discuss the current knowledge on the mechanisms of action and therapeutic opportunities offered by ASCs and ASC-derived EVs in the KT setting. Most relevant pre-clinical and clinical studies as well as actual limitations and future perspective are highlighted

Project status of the CMS tracker optical links

The development phase of the optical data transfer system for the CMS tracker is now complete. This paper presents the project status and reviews the preparation for production. In particular, it focuses on the results of the market surveys for front-end components, and on the performance evaluation of a close-to-final readout chain. I

Inhibition of acetylpolyamine and spermine oxidases by the polyamine analogue chlorhexidine

""Acetylpolyamine and spermine oxidases are involved in the catabolism of polyamines. The discovery of selective. inhibitors of these enzymes represents an important tool for the development of novel anti-neoplastic drugs. Here, a. comparative study on acetylpolyamine and spermine oxidases inhibition by the polyamine analogue chlorhexidine. is reported. Chlorhexidine is an antiseptic diamide, commonly used as a bactericidal and bacteriostatic agent.. Docking simulations indicate that chlorhexidine binding to these enzymes is compatible with the stereochemical. properties of both acetylpolyamine oxidase and spermine oxidase active sites. In fact, chlorhexidine is predicted. to establish several polar and hydrophobic interactions with the active site residues of both enzymes, with binding. energy values ranging from −7.6 to −10.6 kcal\\\/mol. In agreement with this hypothesis, inhibition studies indicate that. chlorhexidine behaves as a strong competitive inhibitor of both enzymes, values of Ki being 0.10 μM and 0.55 μM for. acetylpolyamine oxidase and spermine oxidase, respectively."