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Resumen Antecedentes y objetivos Comparar prospectivamente la tasa de detección de la PET/TC con 68Ga-DOTATATE versus 11C-colina en pacientes con cáncer de próstata en recaída bioquímica y evaluar in vivo la expresión de receptores de la somatostatina con el fin de planificar terapias dirigidas (177Lu-DOTATATE). Material y métodos Analizamos prospectivamente 64 pacientes con recaída bioquímica (mediana PSA: 4,25 ng/mL). Se realizó una PET/TC con 11C-colina y otra con 68Ga-DOTATATE. Se midió el SUVmáx en todas las lesiones. Se consideraron como patrón de referencia las imágenes correlativas, histopatología y/o seguimiento clínico y bioquímico. Resultados La tasa de detección global por paciente fue del 48,43% para 68Ga-DOTATATE y de 46,87% para 11C-colina. Los resultados fueron concordantes en 53 casos (82,81%). El SUV máximo de la 11C-colina fue significativamente mayor que el correspondiente al 68Ga-DOTATATE para todas las lesiones concordantes (n = 130): 6,17 (1,7-15,5) versus 4,38 (1,37-26,7), mediana (rango), para cada radiotrazador, respectivamente (P < 0,0001). Los valores por paciente de sensibilidad y especificidad fueron los mismos para ambas técnicas: 0,82 (0,65-0,93) y 0,9 (0,73-0,98), respectivamente. Aunque la diferencia no fue estadísticamente significativa, la sensibilidad fue menor para pacientes con niveles de PSA inferiores: 0,63 vs. 0,89; p = 0,13. Se encontró una correlación significativa entre el SUVmáx de ambos trazadores (r = 0,41, n = 130, p < 0,0001). Conclusiones La PET/TC con 68Ga-DOTATATE y la PET/TC con 11C-colina parecen poseer alta capacidad de detección de lesiones patológicas en la evaluación de los pacientes con cáncer de próstata en recaída bioquímica. Se necesitan más estudios con el fin de probar el posible valor clínico complementario de estas técnicas PET/TC, y para el 68Ga-DOTATATE para la potencial planificación de terapias mediadas por los receptores de somatostatina (177Lu-DOTATATE). Abstract Background and objectives To prospectively compare the detection rate of 68Ga-DOTATATE versus 11C-choline PET/CT in patients with prostate cancer in biochemical relapse, and to evaluate somatostatin receptor expression in vivo to plan targeted therapies (177Lu-DOTATATE). Material and methods We prospectively analysed 64 patients with biochemical relapse (median PSA: 4.25 ng/mL). A PET/CT was performed with 11C-choline, and another with 68Ga-DOTATATE. The SUVmax was measured in all lesions. The correlative images, histopathology and/or clinical and biochemical follow-up were taken as the reference standard. Results The overall detection rate per patient was 48.43% for 68Ga-DOTATATE and 46.87% for 11C-choline. The results were concordant in 53 cases (82.81%). The maximum SUV of 11C-choline was significantly higher than that of 68Ga-DOTATATE for all the concordant lesions (n=130): 6.17 (1.7-15.5) versus 4.38 (1.37-26.7), median (range) for each radiotracer, respectively (p <.0001). The sensitivity and specificity values per patient were the same for both techniques: 0.82 (0.65-0.93) and 0.9 (0.73-0.98), respectively. Although the difference was not significant, the sensitivity was lower in patients with lower PSA levels: 0.63 vs. 0.89; p =.13. A significant correlation was found between the SUVmax of both tracers (r = 0.41, n = 130, p <.0001). Conclusions 68Ga-DOTATATE PET/CT and 11C-choline PET/CT seem to have a high capacity to detect pathological lesions in the assessment of patients with prostate cancer with biochemical relapse. Further studies are required to test the potential complementary value of these PET/CT techniques, and to evaluate the potential role of 8Ga-DOTATATE for planning somostatin receptor-mediated therapies (177Lu-DOTATATE). [ABSTRACT FROM AUTHOR]

Resumen Objetivos Evaluar la frecuencia de la captación focal de colon como observación incidental en estudios 18 F-FDG PET/TC. Correlacionar dicho hallazgo con resultados histopatológicos. Material y métodos Se analizaron de forma sistemática 30 estudios en los que se constató captación focal del colon de un total de 3.176 PET/TC con 18 F-FDG. Se excluyeron pacientes con neoplasia colorrectal conocida. Se consignó el valor del SUV máximo (SUVm) y el hallazgo morfológico de la TC. Los estudios fueron informados por un médico radiólogo y un médico nuclear. Los hallazgos fueron correlacionados con la endoscopia y la anatomía patológica. Resultados De los 30 pacientes con lesiones focales hipermetabólicas del colon (0,94%), 15 eran hombres y 15 mujeres con edades comprendidas entre los 27 y 73 años (media 55 años). Los motivos de realización de la PET/TC fueron: cáncer broncopulmonar (4), cáncer de mama (4), tumor de origen desconocido (4), melanoma (3), carcinoma renal (3), neoplasia de cuello uterino (2), adenocarcinoma de ovario (2) y otros (8). Se realizaron 23 fibrocolonoscopias (FCC): 10 pacientes (43,4%) presentaron lesiones malignas, 6 pacientes (26,1%) lesiones premalignas y en 7 pacientes (30,4%) no se identificó ninguna lesión o esta fue benigna. En 7 pacientes no se hizo endoscopia por diversos motivos (rechazo del paciente para realizar el estudio, enfermedad oncológica avanzada). Se correlacionó con valores de SUVm y no se encontraron diferencias estadísticamente significativas entre lesiones malignas-premalignas y las lesiones benignas. Conclusiones La captación focal en colon de 18 F-FDG tiene relevancia clínica sobre todo asociada a lesión morfológica en TC, puede tratarse de un segundo tumor o una lesión premaligna. Se recomienda que todas las captaciones focales del colon sean valoradas con endoscopia, tengan o no alteraciones en TC. Objectives To assess the frequency of focal colonic uptake as an incidental observation in 18 F-FDG PET/CT studies, and to correlate this finding with histopathological results. Material and methods Out of a total of 3,176 PET/CT studies with 18 F-FDG systematic analysis was carried out on 30 studies in which colonic focal uptake was observed. Patients with known colorectal neoplasia were excluded. The maximum standardised uptake values (SUVm) and the morphological findings provided by the CT were recorded. The studies were reported by a radiologist and a nuclear medicine doctor. The findings were compared with endoscopy and pathology findings. Results Of the 30 patients with focal hypermetabolic lesions of the colon (0.94%), 15 were men and 15 were women with ages between 27 and 73 (mean 55 years). The reasons for PET/CT were bronchopulmonary cancer (4), breast cancer (4), tumour of unknown origin (4), melanoma (3), renal carcinoma (3), cervical neoplasia (2), adenocarcinoma of ovary (2), and others (8). Of the 23 colonoscopies performed, 10 patients (43.4%) had malignant lesions, 6 (26.1%) had pre-malignant lesions, and in 7 patients (30.4%) no lesion was identified or was benign. No endoscopy was performed on 7 patients for various reasons (patient refusal to perform the study, advanced oncological disease). An analysis was performed with the SUVm, with no statistically significant differences being found between malignant-premalignant lesions and benign lesions. Conclusions Focal uptake in the colon of 18 F-FDG has clinical relevance, and is mainly associated with morphological lesions in CT. It should be evaluated, as it may be a second tumour or a pre-malignant lesion. It is recommended that all focal uptakes of the colon be evaluated with endoscopy. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an analysis of the maximum achievable fill-factor by a pixel detector of Geiger-mode avalanche photodiodes with the Chartered 130nm/Tezzaron 3D process. The analysis shows that fill-factors between 66% and 96% can be obtained with different array architectures and a time-gated readout circuit of minimum area. The maximum fill-factor is achieved when the two-layer vertical stack is used to overlap the non-sensitive areas of one layer with the sensitive areas of the other one. Moreover, different sensor areas are used to further increase the fill-factor. A chip containing a pixel detector of the Geiger-mode avalanche photodiodes and aimed to future linear colliders has been designed with the Chartered 130nm/Tezzaron 3D process to increase the fill-factor. [Copyright &y& Elsevier]

Abstract: It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite gain and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection still remains unexplored. In this contribution, we are going to expose different steps that we have taken in order to prove the efficiency of the Geiger mode avalanche photodiodes in the aforementioned field. In particular, we will present a setup for the characterization of these sensors in a test beam. The expected results of the test beam at DESY and CERN have been simulated with Geant4 and will also be exposed. [Copyright &y& Elsevier]

Abstract: This paper describes the dependence of both volume change during primary solid solution formation and that of volume size factor, V sf on solute mean atomic volume. Our research findings demonstrate a direct relationship between V sf or volume change and solute atomic volume. For twenty solvent elements, the average linear correlation coefficient between V sf and solute atomic volume is 0.659. The average correlation coefficient for volume changes is 0.592. Forty-seven systems solute–solvents with the same crystalline structure indicate that the average linear correlation coefficient between V sf and solute atomic volume is 0.780. The average correlation coefficient between V sf and solute atomic volume is 0.907 for solute elements from the same group in the Periodic Table. The average correlation coefficient for volume changes is 0.775. Forty-eight systems were analyzed. For fourteen elements, it was found that elements with the same crystalline structure have an average correlation coefficient between V sf and solvents atomic volume of 0.934. The relationship between volume changes and solvent atomic volume can be expressed with a quadratic model. Then, volume change during primary solid solution depends upon solute volume, group number and crystalline structure. [Copyright &y& Elsevier]

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Abstract: Unit cell volumes of intermetallic compounds have been calculated using reported volume size factors. An equation to calculate unit cell volume for intermetallics of any crystalline structure was derived from previously reported expressions for L12 and B2 compounds. Average error for 122 analyzed compounds was 3.16%. Errors ranged from 0.00 to 14.01%. Factors that could influence the error value, such as order, structure type, solid solubility, and type of elements forming the compound were evaluated. A combination of solid solubility and type of elements forming the compounds seem to be the most relevant factors influencing the error value. [Copyright &y& Elsevier]

Volume size factors and lattice parameters in cubic intermetallics with L12 or B2 structure have been derived from the “Macroscopic Atom” model. In a first step, an equation has been derived to calculate the volume size factor for binary solid solutions of two transition metals. Then, lattice parameters of cubic intermetallics were calculated with equations found in the literature which only make use of volume size factors and partial molar volumes. While large differences can be found between some of the predicted and observed volume size factors, differences between measured and calculated lattice parameters ranged from 0.05 to −5.45%. [Copyright &y& Elsevier]

An equation has been derived to predict unit cell volume of high entropy alloys, HEA's, by two different methods. In the first method, a HEA is considered as a mixture of solid solutions. Based on an equation previously reported to calculate unit cell volume of intermetallic compounds, an expression to calculate unit cell volume of HEA's was obtained. In the second method, a HEA is modeled as a mixture of solute element atoms surrounded by different environments. Using the effective volume of solute atoms in these environments, the unit cell volume of a HEA was derived. Both treatments led to the same equation. For cubic HEA's lattice parameters were calculated. The predicted lattice parameters were compared with those reported for 79 HEA's. Lattice parameters were also calculated using the equivalent of Vegard's law for these alloys. Average errors were 0.64%, and 0.53% when Vegard's law, and the equation derived in this work were used, respectively. Although these average errors seem acceptable, they were as high as 4.27%, and 4.70% when Vegard's law, and the equation proposed are applied, respectively. The roles on error, of method to determine chemical composition, method to measure lattice parameter, and type of elements present on the alloy were examined. • An equation to predict unit cell volume of HEA's (as a mixture of solid solutions). • An equation to predict unit cell volume of HEA's (solute different environments). • Both treatments led to the same equation. • Lattice parameter of cubic HEA's can be predicted. [ABSTRACT FROM AUTHOR]

A miniature internet of things (IoT)-based point-of-care testing (PoCT) fluorescence reader, able to perform both intensity and time-resolved measurements of different fluorescent tags, is presented. This low cost platform has been conceived for performing tests in low-resource and remote settings, displaying versatile performance and yet simple operation. It consists on an external case of 43 × 30 × 42 mm3 (built in a 3D-printer) where all the elements are fixed, including some basic optics (3 lenses and 2 filters), a laser diode and a custom designed Single-Photon Avalanche Diodes (SPADs) camera. Both, the laser and the camera are controlled by a Field Programmable Gate Array (FPGA) with IoT capabilities. The PoCT was validated by detecting Plasmodium antigen in a fluorescent enzyme-linked immunosorbent assay (ELISA) using a fluorescence substrate. The results were compared to those provided in parallel by two commercial fluorescent plate readers. As it will be shown, the PoCT fluorescent readout was more sensitive than its colorimetric counterpart. Furthermore, the PoCT displayed similar signal trends and levels of detection than the bulkier and more expensive commercial fluorescence plate readers. These results demonstrate that the PoCT platform developed could bring the performance of central laboratory assay techniques closer to the end-user level. • Miniature, Internet of things (IoT)-based, general-purpose point-of-care. • Ability to measure fluorescence intensity as well as time-resolved fluorescence. • Proprietary Complementary Metal-Oxide-Semiconductor Single-Photon Avalanche Diodes camera. • Validated by detecting Plasmodium antigen (Malaria) with an ELISA using a fluorescence substrate. • Comparison with bulky and expensive commercial plate readers. [ABSTRACT FROM AUTHOR]

: Background/aimChanges in immunosuppression and other factors may have changed the severity of recurrent hepatitis C during recent years. This study sought to establish the changes in incidence and severity of recurrent hepatitis C, and its association with the changes in acute rejection and induction immunosuppressive therapy between 1990 and 1999.: Patients and methodsAmong 213 liver transplants in HCV-infected recipients, 129 grafts were selected for this study: all grafts with severe recurrent hepatitis C (fibrosis 3–4 in Scheuer''s score or fibrosing cholestatic hepatitis), and those grafts without severe recurrence with at least 2 years of follow up. Grafts were divided in 5 groups depending on the year of transplantation to compare recurrent hepatitis C-related variables, AR incidence and induction immunosuppression.: ResultsHepatitis-free survival decreased in recent years (p = 0.015). The incidence of fibrosing cholestatic hepatitis was higher among 1996–1997 and the 1998–1999 periods (p = 0.019). Survival free of severe hepatitis at 1 year follow up was 95% in 1990–1991 and 80% in 1998–1999; however, in the long-term the survival was similar between groups (p = 0.933). HCV-related graft survival at 5 years was 93.5% in the 1990–95 period and 82.5% in 1996–99 (p = 0.068). Neither AR nor any regimen of induction immunosuppression was associated with changes in the occurrence of recurrent hepatitis C related survival.: ConclusionsSeverity of recurrent hepatitis C and HCV-related graft loss after liver transplantation were higher in the second half of the 1990s; however, there was no association with AR or induction immunosuppression. [Copyright &y& Elsevier]

Abstract: Avalanche photodiodes operated in the Geiger mode offer a high intrinsic gain as well as an excellent timing accuracy. These qualities make the sensor specially suitable for those applications where detectors with high sensitivity and low timing uncertainty are required. Moreover, they are compatible with standard CMOS technologies, allowing sensor and front–end electronics integration within the pixel cell. However, the sensor suffers from high levels of intrinsic noise, which may lead to erroneous results and limit the range of detectable signals. They also increase the amount of data that has to be stored. In this work, we present a pixel based on a Geiger-mode avalanche photodiode operated in the gated mode to reduce the probability to detect noise counts interfering with photon arrival events. The readout circuit is based on a two grounds scheme to enable low reverse bias overvoltages and consequently lessen the dark count rate. Experimental characterization of the fabricated pixel with the HV–AMS 0.35μm standard technology is also presented in this article. [Copyright &y& Elsevier]

The Belle II experiment comes with a substantial upgrade of the Belle detector and will operate at the SuperKEKB energy-asymmetric e + e − collider with energies tuned to ϒ (4 S) resonance s = 10. 588 GeV. The accelerator has successfully completed the first phase of commissioning in 2016 and the first electron–positron collisions in Belle II took place in April 2018. Belle II features a newly designed silicon vertex detector based on DEPFET pixel and double-sided strip layers. Currently, a subset of the vertex detector is installed (Phase 2 of the experiment). Installation of the full detector (Phase 3) will be completed by the end of 2018. This paper describes the Phase 2 arrangement of the Belle II silicon vertex detector, with focus on the interconnection of detectors and their integration with the software framework of Belle II. Alignment issues are discussed based on detector simulations and first acquired data. [ABSTRACT FROM AUTHOR]

Currently, perovskite structures have had an important impact in the development of gas sensors. In this work, perovskite LaCoO 3 nanoparticles were synthesized by a simple, economic and reproducible processing by the solution method. The reactive precursors were nitrates of lanthanum and cobalt, using ethylenediamine as a chelating agent and distilled water as solvent. The gel formed by the solvent evaporation (through microwave radiation) was dried at 200 °C and later calcined at 300, 400, 500, 600, and 700 °C for 5 h. The samples were analyzed by X-ray diffraction, infrared spectroscopy, thermogravimetry, scanning, transmission, and atomic force microscopies, and nitrogen physisorption. These analyses confirmed the formation of LaCoO 3 nanoparticles (size ~ 47 nm) at relatively low temperatures. The particles showed a continuous connectivity, generating a porous surface with a fibrous appearance. Starting with the synthesized powders, pellets were made and tested as gas sensors in carbon monoxide and propane atmospheres (at concentrations of 0–300 ppm) at different temperatures (25, 150, 250, and 350 °C). The nanoparticles presented high sensitivity, with a greater response in the propane atmosphere. [ABSTRACT FROM AUTHOR]

Trirutile-type CuSb 2 O 6 nanoparticles were synthesized by a simple and economical route, starting from copper nitrate, antimony chloride, ethylenediamine, and ethyl alcohol as solvent. The latter was evaporated by microwave radiation at 140 W. The precursor material was calcined at 200, 300, 400, 500, and 600 °C, and analyzed by powder XRD. The oxide phase was obtained at the last calcination step (600 °C), whose powders were analyzed by field-emission scanning electron (FE-SEM) and transmission electron (TEM) microscopies. Microrods, hexagonal microplates, and nanoparticles with an average size of ~ 51.2 nm were observed. A forbidden bandwidth of 3.41 eV was detected for the direct transition with UV–vis. Tests were carried out on pellets made of the powders in carbon monoxide (CO) and propane (C 3 H 8 ) atmospheres at different concentrations and operating temperatures, obtaining high response at 300 ppm of CO and 500 ppm of C 3 H 8 , both at 300 °C. [ABSTRACT FROM AUTHOR]

The Belle II experiment will run with a reduced beam asymmetry and a factor of 40 higher instantaneous luminosity compared to the Belle experiment. To cope with this and to be able to perform high precision vertex measurements for charge conjugation parity violating processes, a pixel detector based on DEPFET technology will be installed in the center of Belle II. Its basic properties and the DAQ chain are presented in this article. • The Belle II experiment will achieve a 40 times higher luminosity compared to Belle. • To study CP violating processes, Belle II is equipped with a pixel detector. • The pixel detector is based on DEPFET technology with a read out frequency of 30 kHz. • Online data reduction is performed by removing background hits during DAQ. • The goal is a data reduction by a factor of ten for full luminosity. [ABSTRACT FROM AUTHOR]

Abstract: 2024 Al composite reinforced with Al2O3 particles was obtained by mechanical alloying (MA) using Al, Cu and Mg elemental powders as raw materials and Al2O3 nanoparticles as reinforcement. The results shown that as the MA time increased, the non-reinforced (WR) and Al2O3 reinforced powders (R1A and R2A) morphology changed from flake-flattened to equiaxed. Regarding the average particle size, WR group displayed a continuous decreasing value even for a processing time of 10h while R2A and R1A groups shown a constant value for the same time. This led to the conclusion that steady state of the process was reached in shorter times in presence of Al2O3 nanoparticles. It was found that the reinforcement was present in the matrix like isolated particles and small agglomerates which affected the dislocation motion, and it was assumed that this fact caused the increase observed in the microhardness values. There was no evidence of new phase precipitation through MA process. [Copyright &y& Elsevier]

Abstract: The prefrontal cortex is continuously required for working memory processing during wakefulness, but is particularly hypoactivated during sleep and in psychiatric disorders such as schizophrenia. Ammon''s horn CA1 hippocampus subfield (CA1) afferents provide a functional modulatory path that is subjected to synaptic plasticity and a prominent monoaminergic influence. However, little is known about the muscarinic cholinergic effects on prefrontal synapses. Here, we investigated the effects of the muscarinic agonist, pilocarpine (PILO), on the induction and maintenance of CA1-medial prefrontal cortex (mPFC) long-term potentiation (LTP) as well as on brain monoamine levels. Field evoked responses were recorded in urethane-anesthetized rats during baseline (50 min) and after LTP (130 min), and compared with controls. LTP was induced 20 min after PILO administration (15 mg/kg, i.p.) or vehicle (NaCl 0.15 M, i.p.). In a separate group of animals, the hippocampus and mPFC were microdissected 20 min after PILO injection and used to quantify monoamine levels. Our results show that PILO potentiates the late-phase of mPFC LTP without affecting either post-tetanic potentiation or early LTP (20 min). This effect was correlated with a significant decrease in relative delta (1–4 Hz) power and an increase in sigma (10–15 Hz) and gamma (25–40 Hz) powers in CA1. Monoamine levels were specifically altered in the mPFC. We observed a decrease in dopamine, 5-HT, 5-hydroxyindolacetic acid and noradrenaline levels, with no changes in 3,4-hydroxyphenylacetic acid levels. Our data, therefore, suggest that muscarinic activation exerts a boosting effect on mPFC synaptic plasticity and possibly on mPFC-dependent memories, associated to monoaminergic changes. [Copyright &y& Elsevier]

: BackgroundThe purpose of this study was to analyze the incidence, clinical characteristics, treatment, and outcome of upper aerodigestive (UAD) and lung de novo tumors after ortothopic liver transplantation (OLT).: Patients and methodsBetween April 1986 and June 2002, we performed 851 OLT in 753 patients. We excluded pediatric, partial, and hepatorenal transplants and recipients who died within 2 months after OLT. Thus, we analyzed the incidence and outcome of these tumors in 605 patients after OLT.: ResultsWe found 21 (3.5%) tumors in 20 (3.3%) recipients: 14 were UAD tumors (three in floor of the mouth, two in tonsil, one in tongue, one in pharynx, three in larynx, and four in esophagus) and seven were lung tumors. Nineteen patients were men and one was a woman, with a mean age at transplantation of 47.7 ± 8.6 years. Mean time from OLT to tumor diagnosis was 61.7 ± 35.1 years. As risk factors, 70% were heavy smokers, 75% were heavy drinkers, and 70% developed acute rejection. The incidence of these tumors was significantly higher in transplanted patients for alcoholic cirrhosis compared to the nonalcoholic cirrhosis (8.1% vs 0.8%; P < .0001). After surgical excision in 65% of patients, 1-, 2-, and 3-year patient survival were 47.6%, 37.0%, and 19.7%, respectively.: ConclusionThere is a significantly higher incidence of these tumors in male heavy drinkers and/or smokers who underwent OLT for alcoholic cirrhosis; in spite of aggressive surgical treatment, the prognosis is poor. [Copyright &y& Elsevier]