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•This is the first study on metals pollution in this Mediterranean Bay.•Environmental quality guidelines were used to assess the potential ecological risks.•The fractionation analysis ...of sediments showed the bioavailability of the metals.•Statistical analyses aided to better understanding of pollution sources.•Statistical analyses aided to localize the areas more polluted.
Concentrations of heavy metals were measured in sediment and water from Málaga Bay (South Spain). In the later twentieth century, cities such as Málaga, have suffered the impact of mass summer tourism. The ancient industrial activities, and the actual urbanization and coastal development, recreation and tourism, wastewaters treatment facilities, have been sources of marine pollution. In sediments, Ni was the most disturbing metal because Ni concentrations exceeded the effects range low (ERL), concentration at which toxicity could start to be observed in 85% of the samples analyzed. The metal bioavailability decreased in the order: Cd>Ni>Pb>Cu>Cr. In the sea water samples, Cd and Pb were the most disturbing metals because they exceeded the continuous criteria concentration (CCC) of US EPA in a 22.5% and 10.0% of the samples, respectively. Statistical analyses (ANOVA, PCA, CA) were performed.
Suspensions of Pt/C catalyst nanoparticles in Nafion
®-alcohol solutions have been electrosprayed over carbon paper to prepare cathodes for proton exchange membrane fuel cells (PEMFC). Catalyst ...layers with platinum loading ranging from 0.1
mg
Pt
cm
−2 down to 0.0125
mg
Pt
cm
−2 and different Nafion
® contents were obtained by this method. Morphological studies of the catalyst layers by SEM inspection showed fractal structures with a high dispersion of catalyst. Fuel cell performance of membrane-electrode assemblies (MEAs) made from these cathodes revealed a strong dependence on the Nafion
® concentration in the electrosprayed suspension. In the platinum loading range 0.1–0.025
mg
Pt
cm
−2 and optimal Nafion
® content, a linear relation between fuel cell power density and platinum loading has been found, such that a reduction of platinum content by a factor 4 only reduces the performance by roughly a factor 2. However for the lowest platinum loading investigated, 0.0125
mg
Pt
cm
−2, a sharp drop in performance was noticed.
The electrospray technique has been used to develop a methodology to prepare PEMFC electrodes of high performance by depositing catalytic layers with ultra-low Pt loadings – 0.01 mgPt cm−2 – on gas ...diffusion layers (GDLs) supplied with a carbon microporous layer (CMPL). The catalytic deposits exhibit a fractal structuration and good dispersion of the catalyst as they are grown by the aggregation of catalyst particles with size around 100 nm. Membrane-electrode assemblies (MEAs), made with equally loaded electrodes on both sides of the membrane, delivered performances up to roughly 600–700 mW cm−2 that correspond to very high overall platinum utilizations in the interval 30–35 kW gPt−1. This value is about twice the largest Pt-utilization reported up to date for this kind of fuel cells.
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► Catalytic layers with 0.01 mgPt cm−2 loading were generated by electrospray. ► Electrodes with 5 and 25 square centimeter active surface were prepared. ► MEAs made with these electrodes and Nafion membranes were tested in single cells. ► At atmospheric pressure and 40 °C, the MEAs deliver a specific power of 10 kW gPt−1. ► At 3.4 bar gauge pressure and 70 °C, platinum utilization reached 30 kW gPt−1.
The High-Granularity Timing Detector is a detector proposed for the ATLAS Phase II upgrade. The detector, based on the Low-Gain Avalanche Detector (LGAD) technology, will cover the pseudo-rapidity ...region of 2.4<|η|<4.0 with two end caps on each side and a total area of 6.4 m2. The timing performance can be improved by implanting an internal gain layer that can produce signals with a fast rising edge. It significantly improves the signal-to-noise ratio. The required average timing resolution per track for a minimum ionizing particle is 30 ps at the start and 50 ps at the end of the HL-LHC operation. This is achieved with several layers of LGAD. The innermost region of the detector would accumulate a 1MeV neutron-equivalent fluence up to 2.5× 1015 neq/cm2 including a safety factor of 1.5 before being replaced during the scheduled shutdowns. The addition of this new detector is expected to play an important role in the mitigation of high pile-ups at the HL-LHC. The layout and performance of the various versions of LGAD prototypes produced by Hamamatsu (HPK) have been studied by the ATLAS Collaboration. The breakdown voltages, depletion voltages, inter-pad gaps, collected charge as well as the time resolution have been measured and the production yield of large size sensors has been evaluated.
Cathode electrodes for proton exchange membrane fuel cells (PEMFCs) with ultra-low platinum loadings as low as 0.012 mg
Ptcm
−2 have been prepared by the electrospray method. The electrosprayed ...layers have nanostructured fractal morphologies with dendrites formed by clusters (about 100 nm diameter) of a few single catalyst particles rendering a large exposure surface of the catalyst. Optimization of the control parameters affecting this morphology has allowed us to overcome the state of the art for efficient electrodes prepared by electrospraying. Thus, using these cathodes in membrane electrode assemblies (MEAs), a high platinum utilization in the range 8–10 kW g
−1 was obtained for the fuel cell operating at 40 °C and atmospheric pressure. Moreover, a platinum utilization of 20 kW g
−1 was attained under more suitable operating conditions (70 °C and 3.4 bar over-pressure). These results substantially improve the performances achieved previously with other low platinum loading electrodes prepared by electrospraying.
Towards radiation tolerant sensors for pico-second timing, several dopants are explored. Using a common mask, CNM produced LGADs with boron, boron + carbon and gallium gain layers are studied, under ...neutron and proton irradiation. With fluences ranging from
10
14
to
6 × 10
15
n
eq
/cm
2
on both particle species, results focus on acceptor removal, gain reduction via electrical characterization, timing performance and charge collection. An emphasis is placed on stability via dark rate and operating voltage studies.
Introduction
Active surveillance (AS) is considered a suitable management practice for those patients with low‐risk prostate cancer (PCa). At present, however, the role of multiparametric magnetic ...resonance imaging (mpMRI) in AS protocols has not yet been clearly established.
Outcomes
To determine the role of mpMRI and its ability to detect significant prostate cancer (SigPCa) in PCa patients enrolled in AS protocols.
Materials and Methods
There were 229 patients enrolled in an AS protocol between 2011 and 2020 at Reina Sofía University Hospital. MRI interpretation was based on PIRADS v.1 or v.2/2.1 classification. Demographics, clinical, and analytical data were collected and analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for mpMRI in different scenarios. We defined SigPCa and reclassification/progression as a Gleason score (GS) ≥ 3 + 4, a clinical stage ≥T2b, or an increase in PCa volume. Kaplan–Meier and log‐rank tests were used to estimate progression‐free survival time.
Results
Median age was 69.02 (±7.73) at diagnosis, with a 0.15 (±0.08) PSA density (PSAD). Eighty‐six patients were reclassified after confirmatory biopsy, with a suspicious mpMRI an indication for a clear reclassification and risk‐predictor factor in disease progression (p < 0.05). During follow‐up, 46 patients were changed from AS to active treatment mainly due to disease progression. Ninety patients underwent ≥2mpMRI during follow‐up, with a median follow‐up of 29 (15–49) months. Thirty‐four patients had a baseline suspicious mpMRI (at diagnostic or confirmatory biopsy): 14 patients with a PIRADS 3 and 20 patients with ≥PIRADS 4. From 14 patients with a PIRADS 3 baseline mpMRI, 29% progressed radiologically, with a 50% progression rate versus 10% (1/10 patients) for those with similar or decreased mpMRI risk. Of the 56 patients with a non‐suspicious baseline mpMRI (PIRADS < 2), 14 patients (25%) had an increased degree of radiological suspicion, with a detection rate of SigPCa of 29%. The mpMRI NPV during follow‐up was 0.91.
Conclusion
A suspicious mpMRI increases the reclassification and disease progression risk during follow‐up and plays an important role in monitoring biopsies. In addition, a high NPV at mpMRI follow‐up can help to decrease the need to monitor biopsies during AS.
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