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This study investigated the radiation dose to surgeon eye lens for single procedure and normalised to exposure parameters for eight selected neuroradiology, cardiovascular and radiology interventional procedures.The procedures investigated were diagnostic study, Arteriovenous Malformations treatment (AVM) and aneurysm embolization for neuroradiology procedures, Coronary Angiography and Percutaneous Transluminal Coronary Angioplasty (CA-PTCA), Pacemaker and Implantable Cardioverter-Defibrillator implantation (PM-ICD), Endovascular Aortic Repair (EVAR) and Fenestrated Endovascular Aortic Repair (FEVAR) for cardiovascular and electrophysiology procedures. CT-guided lung biopsy was also monitored. All procedures were performed with table-mounted and ceiling-suspended shields (0.5 mm lead equivalent thickness), except for FEVAR and PM-ICD where only a table mounted shield was present, and CT-guided lung biopsy where no shield was used. Dose assessment was performed using a dosemeter positioned close to the most exposed eye of the surgeon, outside the protective eyewear.The surgeon most exposed eye lens median HIn interventional procedures, the 20 mSv/year dose limit for surgeon eye lens exposure might be exceeded if shields or protective eyewear are not used. Surgeon eye lens doses, normalised to single procedures and to exposure parameters, are a valuable tool for determining appropriate radiation protection measures and dedicated eye lens dosemeter assignment.

Summary Introduction The French Society of Gastro-Intestinal Surgery (Societe Francaise de Chirurgie Digestive) and the Association of hepato-bilio-pancreatic and transplantation surgery (Association de Chirurgie Hepato-Bilio-Pancreatique et Transplantation) requested that clinical practice recommendations be established with regard to operating room hygiene. Methods The literature was analyzed according to the High Authority of Health (Haute Autorite de sante [HAS]) methodology and after consultation of the Cochrane and Medline databases. Pertinent references were selected, and supplementary references were hand-picked from the reference lists. Only English or French language papers were retained. The recommendations of learned societies and the World Health Organization were also considered. Results Recommendations were proposed with regard to pre-operative patient preparation, skin preparation, draping, wound edge protectors, surgeon hygiene, wound closure, and operating room environment. Conclusion These clinical practice recommendations should guide and improve the daily practice of gastro-intestinal surgeons.

Resume Introduction La Societe Francaise de Chirurgie Digestive et l’Association de Chirurgie Hepato-Bilio-Pancreatique et Transplantation ont souhaite realiser des recommandations pour la pratique clinique concernant l’hygiene au bloc operatoire. Methodes L’analyse de la litterature a ete effectuee selon la methodologie de la Haute Autorite de Sante (HAS), par consultation des bases de donnees Cochrane et Medline. Une selection manuelle a ete effectuee a partir des references ainsi obtenues. Un tri manuel des references listees dans les articles selectionnes a ete fait a la recherche d’articles pertinents supplementaires. La recherche etait limitee aux articles dont la langue de publication etait l’anglais ou le francais. Les recommandations des principales societes savantes et de l’Organisation Mondiale de la Sante ont egalement ete prises en compte. Sur la base de l’analyse de la litterature, le groupe de travail a propose, chaque fois que possible, des recommandations. Resultats Des recommandations ont ete proposees concernant la preparation preoperatoire du patient, la preparation cutanee, le drapage chirurgical, les dispositifs de protection de la paroi abdominale, l’hygiene du chirurgien, la fermeture parietale, et l’environnement au bloc operatoire. Conclusion Ces recommandations pour la pratique clinique pourront permettre de guider et d’ameliorer la pratique quotidienne des chirurgiens digestifs.

Aim The best form of prophylactic management of a decompressed sigmoid volvulus (SV) is controversial especially in the elderly. We have studied our experience with this condition to assess the short- and long-term results of SV management. Method All patients treated for SV in our department between 2003 and 2013 were retrospectively included. Emergency decompression was attempted in all patients in whom there was no sign of peritonitis. Planned surgical resection was the procedure of choice in young patients. Percutaneous endoscopic colopexy (PEC) was used in high surgical risk patients. Results There were 65 patients (45 males) of median age 71.5 (24–99) years. Non-surgical reduction was performed in 62 with a success rate of 95% (59/62). Recurrence after initial decompression was 67% at a median follow-up of 5 (1–14) years. A prophylactic surgical resection was performed with primary anastomosis in 33 patients. There were no deaths and the major morbidity rate was 6%. At a mean follow-up of 62 months, only 1 (3%) patient had had a recurrence (at 130 months). PEC was performed in six patients of median age 90 (84–99) years and with a median American Society of Anesthesiologists score of 4. Complications included local site infection (n = 2), pain (n = 1) and abdominal wall bleeding (n = 1). After a median follow-up of 2 (1–4) years, three patients died from medical causes and one recurrence occurred 13 months after removal of the PEC tube. Conclusion Prophylactic treatment after initial decompression of SV results in a low rate of recurrence. Planned sigmoid resection is safe and effective. In frail elderly patients, PEC is satisfactory.

Resume Introduction Les tumeurs des voies excretrices superieures (TVEUS) de stade pT3 correspondent a une entite heterogene regroupant les tumeurs infiltrant le parenchyme renal, la graisse peri-pyelique et/ou la graisse peri-ureterale. L’objectif de cette etude etait d’evaluer l’impact pronostique du type d’infiltration tumorale au sein du groupe des tumeurs de stade pT3. Patients et methodes Il s’agit d’une etude retrospective, bicentrique, a partir de 205 patients pris en charge pour une TVEUS entre 1998 et 2012. Cinquante-deux patients etaient de stade tumoral pT3, repartis en 3 sous-groupes : envahissement de la graisse peri-ureterale (pT3U, n = 16), envahissement de la graisse peri-pyelique (pT3G, n = 21), ou infiltration du parenchyme renal (pT3P, n = 15). L’impact du type d’infiltration tumorale sur les survies sans recidive et specifique a ete etudie. Resultats La mediane de suivi etait de 18,9 mois [6–133,4]. L’analyse univariee comparant le groupe pT3P aux tumeurs pT3U + pT3G mettait en evidence une difference significative en termes de survie sans recidive ( p = 0,031) et de survie specifique ( p = 0,026) a la faveur du groupe pT3P qui apparait alors de meilleur pronostic. En analyse multivariee, le sous-groupe pT3 etait un facteur predictif independant en termes de survie sans recidive et de survie specifique ( p = 0,02). Conclusion Les tumeurs pT3 de siege pyelo-caliciel envahissant le parenchyme renal adjacent a la tumeur etaient de meilleur pronostic par rapport a celles envahissant la graisse peri-hilaire ou peri-ureterale. Cette heterogeneite du groupe pT3 pourrait etre prise en consideration afin d’ameliorer la prise en charge des patients. Niveau de preuve 5

Objectif Le but de cette etude randomisee multicentrique etait d’evaluer le pourcentage de fistules anastomotiques symptomatiques chez les patients operes d’une resection anterieure du bas rectum, randomises avec ou sans stomie de protection.

Chemical Vapor Deposited (CVD) polycrystalline diamond has been proposed as a radiation-hard alternative to silicon in the extreme radiation levels occurring close to the interaction region of the Large Hadron Collider. Due to an intense research effort, reliable high-quality polycrystalline CVD diamond detectors, with up to 270 μm charge collection distance and good spatial uniformity, are now available. The most recent progress on the diamond quality, on the development of diamond trackers and on radiation hardness studies are presented and discussed.

The charge collection efficiency (CCE) of heavily irradiated silicon diode detectors was investigated at temperatures between 77 and 200 K. The CCE was found to depend on the radiation dose, bias voltage value and history, temperature, and bias current generated by light. The detector irradiated to the highest fluence 2×10 15 n/cm 2 yields a MIP signal of at least 15000 e − both at 250 V forward bias voltage, and at 250 V reverse bias voltage in the presence of a light-generated current. The “Lazarus effect” was thus shown to extend to fluences at least ten times higher than was previously studied.

Upper tract urinary carcinoma (UTUC) pT3 tumors are a heterogeneous entity including tumors invading the renal parenchyma, tumors with peripelvic fat invasion or peri-ureteral fat invasion. The aim of this study was to evaluate the prognostic significance of these three different groups of pT3 tumors.Between 1998 and 2012, 205 patients with UTUC were operated in two centers, including 52 patients with pT3 tumor stage. pT3 tumors were divided into three groups: peri-ureteral fat invasion (pT3U, n = 16), peripelvic fat invasion (pT3G, n = 21), and renal parenchyma invasion (pT3P, n = 15). The prognostic significance of the type of tumor infiltration was evaluated on specific and disease-free survival.Median follow-up was 18.9 months [6-133.4]. In univariate analysis, renal parenchyma invasion was associated with a better prognostic in both specific (P = 0.026) and disease-free survival (P = 0.031) compared with peripelvic or peri-ureteral fat invasion. Mutivariate analysis retained the pT3 subgroup as an independant prognostic factor in both specific and disease-free survival (P = 0.02).pT3 tumors with renal parenchyma invasion had a better prognosis than those with peripelvic or peri-ureteral fat invasion. The heterogeneity of the pT3 group should be taken into account to improve the care of patients.

This work presents an overview of the most important mechanisms of radiation damage in silicon detectors to be used for high energy experiments in LHC. The changes in the shallow concentration have been studied by thermally stimulated currents (TSC) after proton and neutron irradiation with fluences up to 10/sup 15/ cm/sup -2/ to investigate the role of thermal donors and the donor-removal effect in standard and oxygen enriched silicon with different resistivities. Deep defects in irradiated silicon have been analysed by deep level transient spectroscopy (DLTS) and photo induced current transient spectroscopy (PICTS) in the same materials. The radiation-induced microscopic disorder has been related with the carrier transport properties of irradiated silicon measured by the Hall effect, by capacitance and current vs. voltage characteristics and with charge collection efficiency. The dependence of the irradiated silicon detectors performances on crystal orientation, on incident particle type and on the initial concentration of oxygen and carbon is also discussed.

This chapter initially describes some fundamental aspects of shape memory alloy systems, including essential crystallographic features and how shape memory and superelastic characteristics are derived from these crystal structures and their temperature or stress dependence. Practical shape memory materials such as nitinol are introduced, and the importance of composition, melting methods, and component fabrication and heat treatment is reviewed. Microstructural changes during heat treatment and how these influence material transformation temperatures and mechanical properties are described. Methods for measuring transformation temperatures are briefly reviewed. Minimally invasive device applications for nitinol are reviewed in some detail, with an emphasis on cardiovascular stents, where the materials have been widely utilized. The advantages of the unique features of nitinol in stenting applications are presented and these are substantiated with a review of some clinical applications in coronary, peripheral, and aortic vessel applications. Stenting for other nonvascular indications and other devices such as vena cava filters and septal occluders are also presented. The use of the material in orthodontic and orthopedic applications is summarized, with porous nitinol structures offering interesting opportunities in relation to improved tissue integration. Important performance characteristics such as fatigue, corrosion, and imaging compatibility are also addressed. In conclusion, it is predicted that new applications for nitinol will continue to evolve.

The authors present a clinical case of a patient with mild liver disease and coagulopathy. The diagnosis was reached through careful histologic examination of liver biopsy. Electron microscopy played an important role in confirming the diagnosis.

We report the production and characterization of a form of amorphous carbon with s p-s p(2) hybridization (atomic fraction of sp hybridized species > or =20%) where the predominant sp bonding appears to be (=C=C=)(n) cumulene. Vibrational and electronic properties have been studied by in situ Raman spectroscopy and electrical conductivity measurements. Cumulenic chains are substantially stable in high vacuum conditions for temperatures lower than 250 K and they influence the electrical transport properties of the s p-s p(2) carbon through a self-doping mechanism by pinning the Fermi level closer to one of the mobility gap edges. Upon heating above 250 K the cumulenic species decay to form graphitic nanodomains embedded in the s p(2) amorphous matrix thus reducing the activation energy of the material. This is the first example of a pure carbon system where the s p hybridization influences bulk properties.

We report the production and characterization of a form of amorphous carbon with s p-s p(2) hybridization (atomic fraction of sp hybridized speciesor =20%) where the predominant sp bonding appears to be (=C=C=)(n) cumulene. Vibrational and electronic properties have been studied by in situ Raman spectroscopy and electrical conductivity measurements. Cumulenic chains are substantially stable in high vacuum conditions for temperatures lower than 250 K and they influence the electrical transport properties of the s p-s p(2) carbon through a self-doping mechanism by pinning the Fermi level closer to one of the mobility gap edges. Upon heating above 250 K the cumulenic species decay to form graphitic nanodomains embedded in the s p(2) amorphous matrix thus reducing the activation energy of the material. This is the first example of a pure carbon system where the s p hybridization influences bulk properties.

This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described.

This paper describes the silicon microstrip tracker of the CMS experiment at the future LHC. The silicon tracker consists of a barrel part with 5 layers and two endcaps with 10 disks each. About 6500 modules will have to be built, each one carrying two daisy-chained silicon sensors and their front-end electronics. The modules have been designed to be as simple and robust as possible. Radiation damage in the silicon sensors is minimized by cooling the whole system down to -10°C. Safe operation after heavy irradiation will be possible due to the high-voltage capability of the sensors. We expect the sensors to have a signal-to-noise ratio of 10 at the end of 10years of LHC running, which still gives an efficiency of almost 100%.

New particle physics experiments are correlated with high luminosity and/or high energy. The new generation of colliding beam machines which will be constructed will make an extrapolation of a factor of 100 in the center of mass energy and of 1000 in luminosity beyond present accelerators. The scientific community hopes that very exciting physics results could be achieved this way, from the solution to the problem of electroweak symmetry breaking to the possible discovery of new, unpredicted phenomena. The particles which compose the radiation field are: electrons, pions, neutrons, protons and photons. It has become evident that the problem of the radiation resistance of detectors in this severe environment is a crucial one. This situation is complicated more by the fact that detectors must work all the run time of the machine, and better all the time of the experiment, without replacement (part or whole). So, studies related to the investigation of the radiation hardness of all detector parts, are developing. The studies are in part material and device characterization after irradiation, and in part technological developments, made in order to find harder, cheaper technologies, for larger surfaces. Semiconductor detectors have proven to be a good choice for vertex andmore » calorimeter. Both fixed target machines and colliders had utilized in the past silicon junction detectors as the whole or part of the detection system. Precision beam hodoscopes and sophisticated trigger devices with silicon are equally used. The associated electronics in located near the detectors, and is subjected to the same radiation fields. Studies of material and device radiation hardness are developing in parallel. Here the authors present results on the radiation hardness of silicon, both as a bulk material and as detectors, to neutron irradiation at high fluences.« less

The Authors describe their personal experience in a rare case of total arhinia in a young boy, now seven years old, whose psycho-physical development is normal and who is healthy except for recurrent conjunctivitis due to the absence of nasolacrimal ducts. The Authors consider the possibility that in the case of total absence of the nasal function, as in total arhinia, the oropharyngeal and laryngotracheobronchial mucosa may acquire those functional and defensive properties typically belonging to nasal mucosa. In the subject in question, in fact, functional respiratory and immunosecretory parameters are normal. On the other hand, being well known how problematic acquired severely compromised nasal functions are one would think that only in the case of congenital absence of the nose can the lower aerodigestive structures compensate successfully. In the Authors' opinion this clinic observation contradicts the widely held belief that nasal respiration is absolutely necessary from the moment of birth on.

The breakdown performance of CMS barrelmodule prototype detectors and test devices with single and multi-guard structures were studied before and after neutron irradiation up to 2·1014 1 MeV equivalent neutrons. Before irradiation avalanche breakdown occurred at the guard ring implant edges. We measured 100–300 V higher breakdown voltage values for the devices with multi-guard than for devices with single-guard ring. After irradiation and type inversion the breakdown was smoother than before irradiation and the breakdown voltage value increased to 500–600 V for most of the devices.

We present recent results on the use of Chemical Vapor Deposition (CVD) diamond microstrip detectors for charged particle tracking. A series of detectors was fabricated using 1 x 1 cm 2 diamonds. Good signal-to-noise ratios were observed using both slow and fast readout electronics. For slow readout electronics, 2 μs shaping time, the most probable signal-to-noise ratio was 50 to 1. For fast readout electronics, 25 ns peaking time, the most probable signal-to-noise ratio was 7 to 1. Using the first 2 x 4 cm 2 diamond from a production CVD reactor with slow readout electronics, the most probable signal-to-noise ratio was 23 to 1. The spatial resolution achieved for the detectors was consistent with the digital resolution expected from the detector pitch.

Measurements performed on high resistivity silicon detectors irradiated with proton and neutron fluences, up to 3.5×1014 p/cm2 and 4.0×1015 n/cm2 respectively, are presented. The current-voltage (IV) and capacitancevoltage (CV) characteristics, as well as the charge collection efficiency (CCE) of the devices have been measured to carry out a complete detector performance analysis after irradiation, The IV, CV and CCE analyses show that the irradiated devices depart from the ideal p+n junction modelisation when the fluence (f) is of the order of 1014 ÷ 1015 cm−2. In this fluence range, it is impossible to fully deplete the irradiated device; the CV characteristics show evidence of full depletion voltages up to 103–104 Volts; the IV and CCE(V) curves are found to be linear in this fluence range; reverse currents up to a few mA are measured. A well visible, although low, charge collection signal has been observed at 7°C after exposure to the extreme irradiation fluence of 4.0×1015 n/cm2. This is probably due to a very narrow active region inside the semiconductor bulk, and corresponding approximately, to a 75% inefficiency in the detector performance.

Silicon diodes irradiated with ∼ 1MeV neutron fluences of 2×1012 and 2×1013 cm−2 have been analysed by means of Thermally Stimulated Current (TSC) technique and Capacitance versus Voltage measurements. Both the radiation induced lattice defects and the effective carrier concentration Neff have been measured after irradiation during six months of room temperature self annealing. The sample irradiated with the highest fluence has shown the reverse annealing effect and correspondingly, a broad peak around 0.340–0.400eV is seen to increase strongly for self annealing. Tentative identities for the deep levels responsible for the broad peak are carbon related acceptor traps.

We report on synthesis of diamond films by direct current glow discharge chemical vapour deposition (CVD) prepared at different deposition conditions, for application in high energy physics. The syntesis apparatus is briefly described. Continuous undoped diamond samples have been grown onto Mo substrates with a deposition area up to 1 cm 2 and an electrical resistivity as high as 10 13 Ωcm. The deposition parameters are related to the material properties of the diamonds, investigated by optical spectroscopy, electron microscopy and diffraction analysis. Decreasing the linear growth rate results in good quality films with small remnants of graphite-like phases. The high crystalline quality and phase purity of the films are related to very low values of leakage currents. The particle induced conductivity of these samples is also studied and preliminary results on charge collection efficiency are presented.

International audience; Monolithic Active Pixel Sensors (MAPS) have been proposed as sensing devices for the vertex detectors at the International Linear Collider (ILC), of the STAR upgrade and of the Compressed Baryonic Matter (CBM) experiment. These applications require substantial tolerance to non-ionising doses, which range up to $\sim10^{13}n_{eq}/cm^2$. Intense studies were undertaken in order to measure the, so far widely unknown, radiation hardness of MAPS optimised for charged particle tracking and to identify the dominating effects of non-ionising radiation on these devices. This paper focuses on the recombination of signal electrons in the sensitive volume, which is the dominating problem provoked by bulk damage in MAPS. The dependence of this effect on some aspects of the pixel architecture is discussed, aiming to optimise the latter with respect to radiation tolerance.