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Background: Objective radiographic assessment is crucial for accurately evaluating therapeutic efficacy and patient outcomes in oncology clinical trials. Imaging assessment workflow can be complex; can vary with institution; may burden medical oncologists, who are often inadequately trained in radiology and response criteria; and can lead to high interobserver variability and investigator bias. This article reviews the development of a tumor response assessment core (TRAC) at a comprehensive cancer center with the goal of providing standardized, objective, unbiased tumor imaging assessments, and highlights the web-based platform and overall workflow. In addition, quantitative response assessments by the medical oncologists, radiologist, and TRAC are compared in a retrospective cohort of patients to determine concordance. Patients and Methods: The TRAC workflow includes an image analyst who pre-reviews scans before review with a board-certified radiologist and then manually uploads annotated data on the proprietary TRAC web portal. Patients previously enrolled in 10 lung cancer clinical trials between January 2005 and December 2015 were identified, and the prospectively collected quantitative response assessments by the medical oncologists were compared with retrospective analysis of the same dataset by a radiologist and TRAC. Results: This study enlisted 49 consecutive patients (53% female) with a median age of 60 years (range, 29–78 years); 2 patients did not meet study criteria and were excluded. A linearly weighted kappa test for concordance for TRAC versus radiologist was substantial at 0.65 (95% CI, 0.46–0.85; standard error [SE], 0.10). The kappa value was moderate at 0.42 (95% CI, 0.20–0.64; SE, 0.11) for TRAC versus oncologists and only fair at 0.34 (95% CI, 0.12–0.55; SE, 0.11) for oncologists versus radiologist. Conclusions: Medical oncologists burdened with the task of tumor measurements in patients on clinical trials may introduce significant variability and investigator bias, with the potential to affect therapeutic response and clinical trial outcomes. Institutional imaging cores may help bridge the gap by providing unbiased and reproducible measurements and enable a leaner workflow.

In current Si based PV devices the sun-light-electricity conversion rarely exceeds the 20% in efficiency, stimulating significant efforts towards new solutions and technologies for giving a boost to Si for PV. One of the most promising routes for the 21st century is exploiting the quantum confinement effect in reduced dimensionality systems, with the aim to harvest the full solar spectrum. Recently, it has been proposed that a certain modulation of the optical bandgap (EG OPT) can be attained by changing the size of Si quantum dots (QDs), which should allow for a large absorption of the solar photon flux [1]. By this way, an “all-Si” tandem solar cell could be fabricated, by stacking solar cells with Si QDs of increasing bandgap (with decreasing QD size) upon a bulk Si cell, to absorb sunlight in a more efficient way.

Background: Transcatheter arterial chemoembolisation (TACE) is the treatment of choice for intermediate stage hepatocellular carcinoma (HCC). Doxorubicin-loaded drug-eluting beads (DEB)-TACE is expected to improve the performance of conventional TACE (cTACE). The aim of this study was to compare DEB-TACE with cTACE in terms of time-to-tumour progression (TTP), adverse events (AEs), and 2-year survival. Methods: Patients were randomised one-to-one to undergo cTACE or DEB-TACE and followed-up for at least 2 years or until death. Transcatheter arterial chemoembolisation was repeated ‘on-demand'. Results: We enrolled 177 patients: 89 underwent DEB-TACE and 88 cTACE. The median number of procedures was 2 in each arm, and the in-hospital stay was 3 and 4 days, respectively (P=0.323). No differences were found in local and overall tumour response. The median TTP was 9 months in both arms. The AE incidence and severity did not differ between the arms, except for post-procedural pain, more frequent and severe after cTACE (P

Flexible sensors are gaining increasing interest in a number of applications, including biomedical, food control, domotics and robotics, having very light weight, robustness and low cost. Low temperature polycrystalline silicon (LTPS) technology is particularly attractive for such applications, since LTPS TFTs show excellent electrical characteristics, good stability and offer the possibility to exploit CMOS architectures. Then, as examples of flexible sensing systems, we present a tactile sensor for robotic applications and a pH sensor for biomedical applications. The present results can pave the way to advanced flexible sensing systems, where sensors and local signal conditioning circuits can be integrated on the same flexible substrate.

Superlattices of Si3N4 and Si-rich silicon nitride thin layers with varying thickness were prepared by plasma enhanced chemical vapor deposition. After high temperature annealing, Si nanocrystals were formed in the former Si-rich nitride layers. The control of the Si quantum dots size via the SiNx layer thickness was confirmed by transmission electron microscopy. The size of the nanocrystals was well in agreement with the former thickness of the respective Si-rich silicon nitride layers. In addition X-ray diffraction evidenced that the Si quantum dots are crystalline whereas the Si3N4 matrix remains amorphous even after annealing at 1200 degrees C. Despite the proven Si nanocrystals formation with controlled sizes, the photoluminescence was 2 orders of magnitude weaker than for Si nanocrystals in SiO2 matrix. Also, a systematic peak shift was not found. The SiNx/Si3N4 superlattices showed photoluminescence peak positions in the range of 540-660nm (2.3-1.9 eV), thus quite similar to the bulk Si3N4 film having peak position at 577nm (2.15 eV). These rather weak shifts and scattering around the position observed for stoichiometric Si3N4 are not in agreement with quantum confinement theory. Therefore theoretical calculations coupled with the experimental results of different barrier thicknesses were performed. As a result the commonly observed photoluminescence red shift, which was previously often attributed to quantum-confinement effect for silicon nanocrystals, was well described by the interference effect of Si3N4 surrounding matrix luminescence.

We analyze the results of an extensive characterization study involving electrical and optical measurements carried out on hydrogenated amorphous silicon (alpha-Si:H) thin film materials fabricated under a wide range of deposition conditions. By adjusting the synthesis parameters, we evidenced how conductivity, activation energy, electrical transport and optical absorption of an alpha-Si:H layer can be modified and optimized. We analyzed the activation energy and the pre-exponential factor of the dark conductivity by varying the dopant-to-silane gas flow ratio. Optical measurements allowed to extract the absorption spectra and the optical bandgap. Additionally, we report on the temperature dependence of the activation energy to satisfy the Meyer-Neldel rule. Finally, the influence of the individual films parameters upon the final performances of a single junction pin alpha-Si:H have been studied. The measurements show how a more than doubled enhancement in energy conversion efficiency can be obtained in an alpha-Si:H solar cell with a proper selection of synthesis conditions.

26th European Photovoltaic Solar Energy Conference and Exhibition; 361-366, Aim of this work is the determination of the optical parameters of silicon nanocrystals (nc-Si) in Silicon Rich Carbide (SRC) matrix and in particular of the absorption coefficient of the material, essential in the design of photovoltaic devices. The nanocrystals were formed using the superlattice SRC/SiC approach followed by annealing. The optical properties of the superlattices after annealing up to 1100 °C are investigated. Severe shrinkage of the materials is observed, more marked for higher carbon concentration. Contrary to the case of Silicon Rich Oxide (SRO) matrix, the simulation of R&T spectra based on EMA modeling shows that the material can be described by a mixture of crystallized SiC, crystallized Si, and amorphous Si. Larger Si concentration in the SRC layer leads to larger crystallized fraction. The differences with the SRO case are illustrated and discussed. The results are applied to the optical simulation of a hypothetical tandem device. It is obtained that much thinner absorbers could be used in the SRC case with respect to SRO one.

Producción Científica, In this paper we discuss from an atomistic point of view some of the issues involved in the modeling of electrical characteristics evolution in silicon devices as a result of ion implantation and annealing processes in silicon. In particular, evolution of electrically active dose, sheet resistance and hole mobility has been investigated for high B concentration profiles in pre‐amorphized Si. For this purpose, Hall measurements combined with atomistic kinetic Monte Carlo atomistic simulations have been performed. An apparent anomalous behavior has been observed for the evolution of the active dose and the sheet resistance, in contrast to opposite trend evolutions reported previously. Our results indicate that this anomalous behavior is due to large variations in hole mobility with active dopant concentration, much larger than that associated to the classical dependence of hole mobility with carrier concentration. Simulations suggest that hole mobility is significantly degraded by the presence of a large concentration of boron‐interstitial clusters, indicating the existence of an additional scattering mechanism. Copyright © 2009 John Wiley & Sons, Ltd., Ministerio de Economía, Industria y Competitividad (Project TEC2008-06069)

Experimental evidences and microscopic modelling of the mechanism of B diffusion in Si and Ge are given. In both the lattices B migrates by the mediation of self-interstitials (Is). In Si, B diffusion occurs mainly through the formation of a BI0 complex, after interactions of BS - with I0 or with I++ in intrinsic condition or high hole densities, respectively, followed by a proper charge exchange. A small contribution of the BI- complex is visible only under n-type doping, when BS - and I0 bind nonetheless the pairing of B with the n-dopants. Also in Ge, the B diffusion mechanism has been fixed, even if to a lower extent, revealing the need of selfinterstitials to start the B motion. We evidenced the occurrence of the proton radiation enhanced diffusion (RED) and of the transient enhanced diffusion (TED) of B, modeling both the cases with the central role of Is.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 317-321, The optical properties of silicon nanodots embedded in a dielectric matrix are studied. A critical review of the existing literature is presented, with focus on the specificity of the compositional and structural characteristics of the involved material. The results are applied to the simulation of spectrophotometric measurements taken on thermally treated silicon rich oxide (SRO) grown by Plasma Enhanced Chemical Vapor Deposition. Our results include the determination of the optical properties of the SRO host matrix. Simulation of the R&T data indicate the precipitation of amorphous silicon clusters for annealing temperatures below 1000°C, and subsequent crystallization for higher temperatures. The dielectric function of silicon nanoparticles that form after annealing is observed to closely approach the literature data obtained for samples fabricated by thermal precipitation from a silicon implanted SiO2 matrix.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 730-733, Preliminary experimental results on the fabrication and characterization of Si nanodot multilayers embedded in SiC matrix are presented. Nanometric Si crystals are obtained by thermal annealing of hydrogenated SiCx/SiC multilayers deposited by PECVD onto (001) Si and fused quartz substrates. The samples have been investigated by Transmission Electron Microscopy, Scanning Electron Microscopy, X-ray diffraction, IR optical absorption and UV-VIS-near IR transmittance. Although Si nano-dots formation requires high temperature thermal annealing, we show as the initial low temperature thermal annealing for H out-diffusion is a critical step of the fabrication process.

We addressed issues related to quantitative carrier profiling by scanning capacitance microscopy (SCM) on doped layers with different dimensions, starting from thick (similar to 5 mu m) uniformly doped Si layers down to Si/Si1-xGex/Si quantum wells with nanometre width. We preliminarily discuss the influence of the SCM hardware oil the quantification, by comparing the analyses performed on Si calibration standards with two different atomic force microscopes, i.e. DI3100 by Veeco and XE-100 by PSIA, equipped with different SCM sensors. Furthermore, concentration sensitivity and spatial resolution are deeply discussed considering measurements on special designed samples containing quantum wells Of Si0.75Ge0.25 layers strained between Si films. Measurements were taken on sample cross-sections and oil bevelled samples. A nanometre SCM spatial resolution was demonstrated not only in terms of signal sensitivity, but also in terms of quantitative majority carrier profiling.

In this work, we investigate the effect of performing a high dose 20 keV He+ implant before the implantation of B at low energy (3 keV) in silicon and the subsequent thermal annealing at 800 degrees C. The implants were performed in laterally confined regions defined by opening windows in a SiO2 mask, in order to evidence the impact on a realistic configuration used in device fabrication. High resolution quantitative scanning capacitance microscopy (SCM) combined with cross-section transmission electron microscopy (XTEM) allowed to clarify the role of the voids distribution produced during the thermal annealing on the diffusion and electrical activation of implanted B in Si. Particular evidence was given to the effect of the uniform nanovoids distribution, which forms in the region between the surface and the buried cavity layer.

We addressed the issues related to quantitative carrier profiling by scanning capacitance microscopy (SCM) on doped layers with different dimensions, starting from thick (similar to 5 mu m) uniformly B-doped Si layers, down to Si/Si1-xGex/Si quantum wells with nanometric width. We preliminarly discussed the influence of the SCM hardware on the quantification, by comparing the analyses performed on Si calibration standards with two different atomic force microscopes, i.e., DI3100 by Veeco and XE-100 by PSIA, equipped with different SCM sensors. Furthermore, both concentration and spatial resolution are demonstrated by measurements on specially designed samples containing B-doped quantum wells of Si0.75Ge0.25 layers strained between Si films. Measurements were taken both on cross-sectioned samples and on beveled ones. A SCM spatial resolution of 1 nm with a concentration sensitivity from 5% to 10% was demonstrated by quantitative majority carrier profiling on the B-doped Si/Si0.75Ge0.25/Si heterostructures.

We addressed issues related to quantitative carrier profiling by scanning capacitance microscopy (SCM) on doped layers with different dimensions, starting from thick (similar to 5 mu m) uniformly doped Si layers down to Si/Si1-xGex/Si quantum wells with nanometre width. We preliminarily discuss the influence of the SCM hardware oil the quantification, by comparing the analyses performed on Si calibration standards with two different atomic force microscopes, i.e. DI3100 by Veeco and XE-100 by PSIA, equipped with different SCM sensors. Furthermore, concentration sensitivity and spatial resolution are deeply discussed considering measurements on special designed samples containing quantum wells Of Si0.75Ge0.25 layers strained between Si films. Measurements were taken on sample cross-sections and oil bevelled samples. A nanometre SCM spatial resolution was demonstrated not only in terms of signal sensitivity, but also in terms of quantitative majority carrier profiling.

The interactions among erbium, oxygen and silicon atoms on a Si(1 0 0)-2x1 reconstructed surface have been studied by means of X-ray photoelectron spectroscopy and Rutherford backscattering spectrometry. Erbium and oxygen were deposited at 600 degreesC on the Si surface and their behavior has been observed after different thermal processes. It was found that at 600 degreesC, the formation of a stable surface complex Er-O-Si is obtained together with Si oxidation; after an 800 degreesC annealing, the amount of oxygen bound to Si decreases and the remaining O atoms are mainly bonded to Er. An abrupt change was observed after 900 and 1000 degreesC annealings. which bury the Er atoms about 60 A below the substrate surface. Our results give some hints to hypotise the O diffusion towards the Si bulk.

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No abstract available

Background. Community-Acquired Pneumonia (CAP) is still a significant problem in terms of incidence, mortality rate, particularly in infants and the elderly, and socioeconomic burden. General Practitioners (GPs) are the first reference for patients with this disease, but there are few published studies regarding the outpatient treatment of CAP. Methods. The ISOCAP study aimed to identify the type and outcome of the diagnostic-therapeutic management of CAP by GPs in Italy, within the framework of developing a closer interrelationship between GPs and pulmonary specialists. Thirty-six Pulmonary Divisions throughout Italy each contacted 5 local GPs who agreed to recruit the first 5 consecutive patients who consulted them for suspected CAP within the study’s 1-year observation period. Results. A total of 183 GPs took part in the study and enrolled, by the end of the observation period, 763 CAP patients; of these, complete data was available for 737 patients [males=373, females=364, mean age (±SD) 58.8±19.6 years]. 64.4% of patients had concomitant diseases, mainly systemic arterial hypertension and COPD. Diagnosis of CAP was based by GPs on physical examination only in 41.6% of cases; in the remaining chest X-ray was also performed. In only 4.6% of patients were samples sent for microbiological analysis. All patients were treated with antibiotics: 76.7% in mono-therapy, 23.3% with a combination of antibiotics. The antibiotic class most prevalently used in mono-therapy was cephalosporin, primarily ceftriaxone; the most frequently used combinations were cephalosporin+macrolide and cephalosporin+quinolone. Mono-therapy was effective in 70% of cases, the combination of two or more antibiotics in 91.2% of patients. Overall treatment efficacy was 94.7%; hospitalisation was required in 8.5% of cases. Conclusions. Outpatient management of CAP by GPs in Italy is effective, hospitalisation being necessary only in the most severe cases due to age, co-morbidities or extent of pneumonia. This signifies a very significant savings in national health costs.

Thin layers of MoOx have been deposited by thermal evaporation followed by post-deposition annealing. The density of states distributions of the MoOx films were extracted deconvoluting the absorption spectra, measured by a photothermal deflection spectroscopy setup, including the small polaron contribution. Results revealed a sub-band defect distribution centered 1.1 eV below the conduction band; the amplitude of this distribution was found to increase with post-deposition annealing temperature and film thickness.

The increasing interest in thin flexible and bendable devices has led to a strong demand for mechanically robust and electrically reliable transparent electrodes. Indium doped Tin Oxide (ITO) and Aluminium doped Zinc Oxide (AZO) are among the most employed transparent conductive oxides (TCO) and their reliability on flexible substrates have thus received a great attention. However, a high flexibility is usually achieved at very low thickness, which, unfortunately, compromises the electrical conductivity. Here we report the effects of mechanical bending cycles on the electrical and optical properties of ultra thin AZO/Ag/AZO multilayers (45 nm/10 nm/45 nm) and, for comparison, of AZO and ITO single layers whose thickness was, in both cases, 100 nm and 700 nm, deposited at room-temperature on flexible polyethylene naphthalate (PEN) plastic substrates. The electrical stability of the films after several cycles of bending were evaluated by monitoring the relative variation of the electrical resistance with respect to the as prepared sample; the structural damage induced by bending was detected by Scanning Electron Microscopy (SEM). We observed an excellent electrical stability and high flexibility in the AZO/Ag/AZO sample even after 100 cycles, whereas for the single AZO and ITO films the resistivity rapidly increases. The experimental results and numerical simulations provide clear evidences of the key role played by the ductile Ag interlayer that provides improved robustness under mechanical strain.