151 research outputs found
Epuraea imperialis (Reitter, 1877). New invasive species of Nitidulidae (Coleoptera) in Europe, with a checklist of sap beetles introduced to Europe and Mediterranean areas
Australian species Epuraea imperialis (Reitter, 1877), previously introduced to New Zealand, is recorded as a new invasive species from the Canary Islands, Continental Spain, Portugal, France, Belgium, and Italy. It is redescribed and figured, and its taxonomic position in the genus Epuraea Erichson, 1843 is discussed. A tentative checklist of sap beetles introduced to Europe and the Mediterranean areas is finally included
Political advertising on social media: Issues sponsored on Facebook ads during the 2019 General Elections in Spain
Facebook’s advertising platform provides political parties with an electoral tool that enables them to reach an extremely detailed audience. Unlike television, the sponsored content on Facebook is seen only by the targeted users. This opacity was an obstacle to political communications research until Facebook released advertiser-sponsored content in 2018. The company’s new transparent policy included sharing metadata related to the cost and number of impressions the ads received. This research studies the content sponsored on Facebook by the five main national political parties in Spain during the two General Elections held in 2019. The research corpus consists of 14,684 Facebook ads. An extraction algorithm detected the key terms in the text-based messages conveyed in the ad. The prominence of these topics was estimated from the aggregate number of impressions accumulated by each term. Different content patterns were assessed following three categories: user mobilization, candidate presence, and ideological issues. PSOE and PP positioned themselves more toward calls to action. Podemos had the greater number of issues related to policy among the most salient topics in its advertising. Ciudadanos’ strategy focused more on its candidate and mobilization. Vox sponsored few Facebook ads, and they barely included policy issues. Spain was a highly prominent term in all parties’ campaigns. Ciudadanos shared the middle ground on the ideological axis: they promoted social issues more aligned with left-wing parties as well as economic topics usually advocated by the right-wing. Overall, our results point to a greater emphasis on candidates rather than issues
Progress report on the MEDAMI 2019 and CTR research at the DMIL in i3M
[EN] This contribution reports on the recently held MEDAMI 2019 workshop in Valencia (15-17th May 2019). This workshop is about advanced molecular imaging and the main topic of this last edition was Imaging in Immunotherapy. Around 70 attenders met together during three days. This meeting made it possible to join medical doctors and instrumentalists. In MEDAMI 2019 it was exposed the new immunotherapies from a clinical and research point of view. It was shown the already observed improvements when using these therapies. At the same time, we heard about the difficulties and limitations of current molecular imaging in this particular field. It was clear that improvements in system sensitivity and resolution are demanded. Timing information can be utilized in different ways to improve the image quality in PET systems. Precise Coincidence Time Resolution (CTR) improves the signal-to-noise ratio and, therefore, the image contrast, allowing for instance to distinguish low uptake tumors, multicentric lesions, or tumor heterogeneity, to name but a few. Both high time resolution and angular coverage in a PET system can improve the effective sensitivity. An example of a system benchmarking the timing resolution is the Siemens Biograph Vision with 214 ps FWHM, enhancing the detectability. The Explorer total-body PET from UC Davis improves the system sensitivity by having a 2 meters long PET scanner. Deep investigations, from different research groups, are being carried out to further push the limits of timing resolution. This work also describes some of the projects on high timing performance that are being carried out at the Detector for Molecular Imaging Lab (DMIL) at the Institute for Instrumentation in Molecular Imaging (i3M) in Valencia. The DMIL group has extensively worked on detectors and implementation of PET systems enabling the use of accurate timing information. In this progress report we describe the results obtained at the DMIL regarding timing determination in gamma-ray detectors both based on monolithic and pixelated crystals. Although with 15 min thick LYSO blocks it was tough to obtain values of CTR below 500 ps when using analog SiPMs and ASIC-based readout, this was improved down to 250 ps if small 3 mm size and 6 mm height pixels under the one-to-one coupling approach were enabled. This type of approach, the one-to-one coupling, seems to benefit from the light collection in a single photosensor element and, therefore, to improve the timing properties. Monolithic blocks offer, on the contrary, advantages such as photon depth of interaction. In order to separate Compton and photoelectric events we have thought of a detector block design with a high aspect ratio, using LYSO crystals of 51 mm size vs. 3 mm thickness, read-out by the four lateral sides. We have demonstrated the possibility to reach below 2 mm FWHM spatial resolution with an energy resolution of 12%.The DMIL work presented in this paper has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 695536). It has also been supported by the Spanish Ministerio de Economia, Industria y Competitividad under Grant TEC2016-79884-C2-1-R. The author would like to thank all current and former members of the DMIL at i3M for their continuous contributions to this work.González Martínez, AJ.; Barrio, J.; Lamprou, E.; Ilisie, V.; Sánchez Martínez, F.; Benlloch Baviera, JM. (2020). Progress report on the MEDAMI 2019 and CTR research at the DMIL in i3M. Il Nuovo cimento C. 43(1):1-10. https://doi.org/10.1393/ncc/i2020-20005-8S11043
Dynamic beamforming for large area scan in array-based photoacoustic microscopy
[EN] We explore the use of a beamforming method intended for large-area scanning in optical-resolution photoacoustic microscopy. It has been evaluated in a experimental setup that comprises a low-cost laser diode and a phase array with a 128-elements linear probe. Three different beamforming strategies are discussed: no-beamforming, static beamforming and dynamic beamforming. The method has been tested in gelatine-based phantoms as well as ex-vivo organs. Results show that, compared with the other two, dynamic beamforming increases up to 15dB and homogenizes signal-to-noise ratio (SNR) along images of roughly 1 cm2. The method and system presented here could be the baseline for more advanced array-based systems that leverage the low-cost laser sources for clinical applications.This research has been supported by the Spanish Ministry
of Science, Innovation and Universities through grant Juan de
la Cierva - Incorporacion (IJC2018-037897-I), and program Proyectos I+D+i 2019 (PID2019-111436RB-C22). Action
co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of
the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022).
A.C. received financial support from Generalitat Valenciana
and Universitat Politecnica de Val ` encia through the grants APOSTD/2018/229 and program PAID-10-19, respectively.Cebrecos, A.; García-Garrigós, JJ.; Descals, A.; Jimenez, N.; Benlloch Baviera, JM.; Camarena Femenia, F. (2020). Dynamic beamforming for large area scan in array-based photoacoustic microscopy. IEEE. 1-4. https://doi.org/10.1109/IUS46767.2020.9251519S1
Persistence Through Collaboration at Sea for Off-Shore and Coastal Operations
Collaboration (Bruzzone et al. 2013a, b, c, d, e, f) is often mentioned as an opportunity to develop new capabilities for autonomous systems; indeed this paper proposes a practical application where use this approach to enhance the autonomy of the systems during operations in coastal areas or around offshore platforms. The proposed case deals with developing a collaborative approach (Bruzzone et al. 2013a, b, c, d, e, f) among an USV (Unmanned Surface Vehicle) with several AUV (Autonomous Underwater Vehicles) to guarantee persistent surveillance over a marine area (Shkurti et al. 2012). Obviously, the proposed solution could be adopted also for defense and homeland security (Bruzzone et al. 2011a, b, 2010) as well as for archeological site protection in consistence with related cost analysis. The authors propose a technological solution as well as a simulation framework to validate and demonstrate the capabilities of this new approach as well as to quantify expected improvements
An investigation of the hidden structure of states in a mean field spin glass model
We study the geometrical structure of the states in the low temperature phase
of a mean field model for generalized spin glasses, the p-spin spherical model.
This structure cannot be revealed by the standard methods, mainly due to the
presence of an exponentially high number of states, each one having a vanishing
weight in the thermodynamic limit. Performing a purely entropic computation,
based on the TAP equations for this model, we define a constrained complexity
which gives the overlap distribution of the states. We find that this
distribution is continuous, non-random and highly dependent on the energy range
of the considered states. Furthermore, we show which is the geometrical shape
of the threshold landscape, giving some insight into the role played by
threshold states in the dynamical behaviour of the system.Comment: 18 pages, 8 PostScript figures, plain Te
NEMA Performance Evaluation of CareMiBrain dedicated brain PET and Comparison with the whole-body and dedicated brain PET systems
[EN] This article presents system performance studies of the CareMiBrain dedicated brain PET according to NEMA NU 2-2012 (for whole-body PETS) and NU 4-2008 (for preclinical PETs). This scanner is based on monolithic LYSO crystals coupled to silicon photomultipliers. The results obtained for both protocols are compared with current commercial whole body PETs and dedicated brain PETs found in the literature. Spatial resolution, sensitivity, NECR and scatter-fraction are characterized with NEMA standards, as well as an image quality study. A customized image quality phantom is proposed as NEMA phantoms do not fulfil the necessities of dedicated brain PETs. The full-width half maximum of the radial/tangential/ axial spatial resolution of CareMiBrain reconstructed with FBP at 10 and 100 mm from the system center were, respectively, 1.87/1.68/1.39 mm and 1.86/1.91/1.40 mm (NU 2-2012) and 1.58/1.45/1.40 mm and 1.64/1.66/1.44 mm (NU 4-2008). Peak NECR was 49 kcps@287 MBq with a scatter fraction of 48% using NU 2-2012 phantom. The sensitivity was 13.82 cps/kBq at the center of the FOV (NU 2-2012) and 10% (NU 4-2008). Contrast recovery coefficients for customizing image quality phantom were 0.73/0.78/1.14/1.01 for the 4.5/6/9/12 mm diameter rods. The performance characteristics of CareMiBrain are at the top of the current technologies for PET systems. Dedicated brain PET systems significantly improve spatial resolution and sensitivity, but present worse results in count rate measurements and scatter-fraction tests. As for the comparison of preclinical and clinical standards, the results obtained for solid and liquid sources were similar.This study was funded by the Spanish Ministry of Science, Innovation and University under grant RTC-2016-5186-1, a project co-financed by the European Union through the European Regional Development Fund (ERDF). CareMiBrain system was funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 711323. Author Dr. Jose Maria Benlloch owns a small percentage of Oncovision S.A. The other authors declare no potential conflict of interest.Moliner, L.; Rodriguez-Alvarez, MJ.; Catret Mascarell, JV.; González Martínez, AJ.; Ilisie, V.; Benlloch Baviera, JM. (2019). NEMA Performance Evaluation of CareMiBrain dedicated brain PET and Comparison with the whole-body and dedicated brain PET systems. Scientific Reports. 9(15484 (2019)):1-10. https://doi.org/10.1038/s41598-019-51898-zS110915484 (2019)NEMA NU 2-2007. Performance measurements of Positron Emission Tomographs. (Association, National Electrical Manufacturers, 2007).NEMA NU 2-2012. Performance Measurements of Positron Emission Tomographs. (Association, National Electrical Manufacturers, 2012).NEMA NU 4-2008. Performance measurements of Small Animal Positron Emission Tomographs. (Association, National Electrical Manufacturers, 2008).INTERREG IVB SUDOE (SIZING_SUDOE-SOE3/P1/E482). Red transrregional para la transferencia tecnológica y la innovación en el sector de la moda y confección de la región SUDOE a través de la explotación de bases de datos antropométricas 3D de la población (2012).González-Montoro, A. et al. Detector block performance based on a monolithic LYSO crystal using a novel signal multiplexing method. Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip., https://doi.org/10.1016/j.nima.2017.10.098 (2018).Bailey, D. L., Townsend, D. W., Valk, P. E. & Maisey, M. N. Positron Emission Tomography - Basic Sciences, https://doi.org/10.1002/cncr.22968 (Springer, 2005).Madsen, M. T. Emission Tomography: the Fundamentals of Pet and Spect, https://doi.org/10.1097/00024382-200504000-00016 (Elsevier Academic Press, 2005).Reader, A. J. et al. Accelerated list-mode EM algorithm. IEEE Trans. Nucl. Sci. 49, 42–49 (2002).Grootoonk, S., Spinks, T. J., Sashin, D., Spyrou, N. M. & Jones, T. Correction for scatter in 3D brain PET using a dual energy window method. Phys. Med. Biol. 41, 2757–2774 (1996).Rokkita, O., Casey, M., Wienhard, K. & Pictrzyk, U. Random corrections for positron emission tomography using singles count rates. In IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC) 3, 37–40 (2000).Soriano, A. et al. Attenuation correction without transmission scan for the MAMMI breast PET. Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip. 648, 75–78 (2011).Siddon, R. L. Fast calculation of the exact radiological path for a three dimensional CT array. Med. Phys. 12, 252–255 (1985).Watanabe, M. et al. Performance evaluation of a high-resolution brain PET scanner using four-layer MPPC DOI detectors. Phys. Med. Biol. 62, 7148–7166 (2017).Grogg, K. S. et al. NEMA and clinical evaluation of a novel brain PET-CT scanner. J. Nucl. Med. 57, 646–652 (2016).Kolb, A. et al. Technical performance evaluation of a human brain PET/MRI system. Eur. Radiol. 22, 1776–1788 (2012).Karp, J. S. et al. Performance of a brain PET camera based on anger-logic gadolinium oxyorthosilicate detectors. J. Nucl. Med. 44, 1340–1349 (2003).Jong, H. W. A. M. D. et al. Performance evaluation of the ECAT HRRT: an LSO-LYSO double layer high resolution, high sensitivity scanner. Phys. Med. Biol. 52, 1505–1526 (2007).Yoshida, E. et al. The jPET-D4: Performance evaluation of four-layer DOI-PET scanner using the NEMA NU2-2001 standard. In IEEE Nuclear Science Symposium Conference Record, 2532–2536, https://doi.org/10.1109/NSSMIC.2006.354425 (2006).Jung, J. et al. Performance evaluation of GAPD-based brain PET. In IEEE Nuclear Science Symposium Conference Record, 2–5, https://doi.org/10.1109/NSSMIC.2013.6829113 (2013).Yamamoto, S., Honda, M., Oohashi, T., Shimizu, K. & Senda, M. Development of a brain PET system, PET-Hat: A wearable PET system for brain research. IEEE Trans. Nucl. Sci. 58, 668–673 (2011).Musa, M. S., Ozsahin, D. U. & Ozsahin, I. Simulation and evaluation of a cost-effective high-performance brain PET scanner. J. Biomed. Imaging Bioeng. 1, 53–59 (2017).Benlloch, J. M. et al. The MINDVIEW project: First results. Eur. Psychiatry 50, 21–27 (2018).Chang, C.-M., Lee, B. J., Grant, A. M., Groll, A. N. & Levin, C. S. Performance study of a radio-frequency field-penetrable PET insert for simultaneous PET/MRI. IEEE Trans. Radiat. Plasma Med. Sci. 2, 442–431 (2018).Wang, Z., Yu, W. & Xie, S. A dedicated PET system for human brain and head/neck imaging. In IEEE Nuclear Science Symposium Conference Record, 1–4, https://doi.org/10.1109/NSSMIC.2013.6829112 (2013).Bauer, C. E. et al. Concept of an upright wearable positron emission tomography imager in humans. Brain Behav. 6, 1–10 (2016).Moghaddam, N. M., Karimian, A., Mostajaboddavati, S. M., Vondervoort, E. & Sossi, V. Preliminary design and simulation of a spherical brain PET system (SBPET) with liquid xenon as scintillator. Nukleonika 54, 33–38 (2009).Tashima, H., Ito, H. & Yamaya, T. A proposed helmet-PET with a jaw detector enabling high-sensitivity brain imaging. In IEEE Nuclear Science Symposium Conference Record, 8–10, https://doi.org/10.1109/NSSMIC.2013.6829074 (2013).Ahmed, A. M., Tashima, H., Yoshida, E., Nishikido, F. & Yamaya, T. Simulation study comparing the helmet-chin PET with a cylindrical PET of the same number of detectors. Phys. Med. Biol. 62, 4541–4550 (2017).Jung, J., Choi, Y., Jung, J. H., Kim, S. & Im, K. C. Performance evaluation of neuro-PET using silicon photomultipliers. Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip. 819, 182–187 (2016).Kaneta, T. et al. Initial evaluation of the Celesteion large-bore PET/CT scanner in accordance with the NEMA NU2-2012 standard and the Japanese guideline for oncology FDG PET/CT data acquisition protocol version 2.0. EJNMMI Res. 7, 1–12 (2017).Rausch, I. et al. Performance evaluation of the Biograph mCT Flow PET/CT system according to the NEMA NU2-2012 standard. EJNMMI Phys. 2, 1–17 (2015).Karlberg, A. M., Sæther, O., Eikenes, L. & Goa, P. E. Quantitative comparison of PET performance—siemens biograph mCT and mMR. EJNMMI Phys. 3 (2016).Delso, G. et al. Performance Measurements of the Siemens mMR Integrated Whole-Body PET/MR Scanner. J. Nucl. Med. 52, 1914–1922 (2011).Miller, M. A., Molecular, A. & Physics, I. Philips Vereos White Paper. K. Philips N.V. 16 (2016).Kolthammer, J. A. et al. Performance evaluation of the ingenuity TF PET/CT scanner with a focus on high count-rate conditions. Phys. Med. Biol. 59, 3843–3859 (2015).Zaidi, H. et al. Design and performance evaluation of a whole-body Ingenuity TF PET-MRI system. Phys. Med. Biol. 56, 3091–3106 (2011).Jha, A. K. et al. Acceptance test of GEmini TF 16 PET scanner based on NEMA NU-2 and perfomance characteristics assesment for eighteen months in a high volume department. J. Nucl. Med. Technol. 44, 36–42 (2016).Grant, A. M. et al. NEMA NU 2-2012 performance studies for the SiPM-based ToF-PET component of the GE SIGNA PET/MR system. Med. Phys. 43, 2334–2343 (2016).Hsu, D. F. C. et al. Studies of a Next-Generation Silicon-Photomultiplier–Based Time-of-Flight PET/CT System. J. Nucl. Med. 58, 1511–1518 (2017).Reynés-Llompart, G. et al. Performance Characteristics of the Whole-Body Discovery IQ PET/CT System. J. Nucl. Med. 58, 1155–1161 (2017)
Impact of food preservatives based on immobilized phenolic compounds on an in vitro model of human gut microbiota
[EN]
To address concerns about the biocompatibility of novel phenolic immobilization-based food preservatives, their impact on the composition and metabonomic profile of a defined community of human gut microbiota was evaluated. Three phenolics (eugenol, vanillin and ferulic acid) presented in two forms (free or immobilized on different supports) were tested at two concentration levels (0.5 and 2 mg/mL). Free eugenol was the phenolic with the greatest impact on gut microbiota, with a remarkable increase in the abundance of Lachnospiraceae and Akkermansiaceae families. In contrast, immobilized phenolics produced an increase in the abundance of Bac-teroides with a reduction in the ratio of Firmicutes to Bacteroidetes. The metabonomic profile was also affected by free and immobilized phenolics differently in terms of fermentation by-products and phenolic biotransformation metabolites. Thus the results suggest the importance of evaluating the impact of new compounds or materials added to food on human gut microbiota and their potential use to modulate microbiota composition.The authors gratefully acknowledge the financial support from the grant RTI2018-101599-B-C21 of the project "Retos Investigacion" funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe". M.R.R. acknowledges the Generalitat Valenciana for her postdoctoral fellowship (APOSTD/2019/118)Ruiz Rico, M.; Renwick, S.; Vancuren, SJ.; Robinson, AV.; Gianetto-Hill, C.; Allen-Vercoe, E.; Barat Baviera, JM. (2023). Impact of food preservatives based on immobilized phenolic compounds on an in vitro model of human gut microbiota. Food Chemistry. 403. https://doi.org/10.1016/j.foodchem.2022.13436340
Influence of free and immobilized chitosan on a defined human gut microbial ecosystem
[EN] In this work, the influence of different forms of presentation of chitosan in the human gut microbiota with a defined bacterial community was evaluated. First, the susceptibility of individual gut bacterial isolates against chitosan was studied within a concentration range between 0.125 and 1 mg/mL. Then, the impact of chitosan (0.25 and 1 mg/mL) on a defined human gut microbial ecosystem was studied by metagenomic and metabonomic analyses. The results showed that chitosan in its free form had a high impact on individual isolates with a minimum inhibitory concentration below 1 mg/mL for most of the strains studied. In comparison, chitosan immobilized in the different carriers displayed a diverse effect on gut microbiota. The most susceptible strains were Agathobacter rectalis strain 16-6-I 1 FAA, Clostridium spiroforme strain 16-6-I 21 FAA and Mediterraneibacter faecis strain 16-6-I 30 FAA. The impact of the different modes of presentation of chitosan was strain-specific and species-specific when compared to results obtained from analysis of other strains within the genera Agathobacter, Clostridium and Mediterraneibacter, and therefore a study using a defined ecosystem was needed to extrapolate the results. Significant decreases in defined community richness and diversity and changes in metabolic profile were observed after exposure to free chitosan. Free chitosan produced significant reductions in the abundance of the genera Lachnoclostridium, Anaerotignum, Blautia, Enterococcus, Eubacterium and Ruthenibacterium together with a slight decrease of the production of SCFAs, among other fermentation by-products. The immobilized chitosan significantly alleviated the impact caused by the antimicrobial polymer and significantly increased the relative abundance of the Bacteroidetes phylum compared to free chitosan. These results suggest the significance of assessing the impact of new ingredients and materials included in food on the human gut microbiota with models that simulate the gastrointestinal environment, such as in vitro bioreactor systems.The authors gratefully acknowledge the financial support from the grant RTI2018-101599-B-C21 of the project "Retos Investigacion" funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe". MRR acknowledges the Generalitat Valenciana for her postdoctoral fellowship (APOSTD/2019/118).Ruiz Rico, M.; Rendwick, S.; Vancuren, SJ.; Robinson, AV.; Gianetto-Hill, C.; Allen-Vercoe, E.; Barat Baviera, JM. (2022). Influence of free and immobilized chitosan on a defined human gut microbial ecosystem. Food Research International. 161:1-11. https://doi.org/10.1016/j.foodres.2022.11189011116
- …