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The flows’ idea is a fundamental issue regarding the computational creation within the Hispanic sphere, due to the historical and social context itself of today’s globalization and transnationality as much as the core theme of some key works and the career of the authors, among whom some Hispanic writers who create and publish their works within the peninsular Spanish scope stand out. On the other hand, the idea of nomadism merges with the communication on the Internet, which global reach enables simultaneous dialogues between people in different places in the world. Therefore, the Internet assumes a new spatial conception beyond the real physical territory. Moreover, from an artistic point of view, space is dealt by means of the rules that govern the screen, where a new visualization of the subgenres of the digital poetry is different from the linear analogue reading.

A drug delivery nanosystem of noble bimetallic nanoparticles (NPs) which consists of Au NPs capped with Pt NPs (Au@Pt NPs) is constructed and functionalised with a quinazoline based small molecule (Au@Pt@Q NPs), acting as a theranostic agent against glioblastoma. Two different hydrothermal synthetic procedures for bimetallic Au@Pt NPs are presented and the resulting nanostructures are fully characterised by means of spectroscopic and microscopic methods. The imaging and targeting capacity of the new drug delivery system is assessed through fluorescent optical microscopy and cytotoxicity evaluations. The constructed Au@Pt NPs consist a monodispersed colloidal solution of 25 nm with photoluminescent, fluorescent and X-Ray absorption properties that confirm their diagnostic potential. Haemolysis testing demonstrated that Au@Pt NPs are biocompatible and fluorescent microscopy confirmed their entering the cells. Cytological evaluation of the NPs through MTT assay showed that they do not inhibit the proliferation of control cell line HEK293, whereas they are toxic in U87MG, U251 and D54 glioblastoma cell lines; rendering them selective targeting agents for treating glioblastoma., (Copyright © 2022. Published by Elsevier B.V.)

Background: Bioprosthetic valve thrombosis may have implications for valve function and durability., Objectives: Using a novel glycoprotein IIb/IIIa receptor radiotracer 18F-GP1, we investigated whether positron emission tomography (PET)-computed tomography (CT) could detect thrombus formation on bioprosthetic aortic valves., Methods: Ex vivo experiments were performed on human platelets and explanted bioprosthetic aortic valves. In a prospective cross-sectional study, patients with either bioprosthetic or normal native aortic valves underwent echocardiography, CT angiography, and 18F-GP1 PET-CT., Results: Flow cytometric analysis, histology, immunohistochemistry, and autoradiography demonstrated selective binding of 18F-GP1 to activated platelet glycoprotein IIb/IIIa receptors and thrombus adherent to prosthetic valves. In total, 75 participants were recruited: 53 with bioprosthetic valves (median time from implantation 37 months [IQR: 12-80 months]) and 22 with normal native aortic valves. Three participants had obstructive valve thrombosis, and a further 3 participants had asymptomatic hypoattenuated leaflet thickening on CT angiography. All bioprosthetic valves, but none of the native aortic valves, demonstrated focal 18F-GP1 uptake on the valve leaflets: median maximum target-to-background ratio 2.81 (IQR: 2.29-3.48) vs 1.43 (IQR: 1.28-1.53) (P < 0.001). Higher 18F-GP1 uptake was independently associated with duration of valve implantation and hypoattenuated leaflet thickening. All 3 participants with obstructive valve thrombosis were anticoagulated for 3 months, leading to resolution of their symptoms, improvement in mean valve gradients, and a reduction in 18F-GP1 uptake., Conclusions: Adherence of activated platelets is a common and sustained finding on bioprosthetic aortic valves. 18F-GP1 uptake is higher in the presence of thrombus, regresses with anticoagulation, and has potential use as an adjunctive clinical tool. (18F-GP1 PET-CT to Detect Bioprosthetic Aortic Valve Thrombosis; NCT04073875)., Competing Interests: Funding Support and Author Disclosures This work was funded by the British Heart Foundation, London, United Kingdom (RG/16/10/32375 and PG/19/40/34422). The Edinburgh Clinical Research Facilities and Edinburgh Imaging facility is supported by the National Health Service Research Scotland (NRS) through National Health Service Lothian Health Board. This work and Drs Bing, Tzolos, Williams, Dweck, and Newby are supported by the British Heart Foundation (PG/19/40/34422, FS/ICRF/20/26002, FS/CRTF/20/24086, FS/14/78/31020, CH/09/002, RG/16/10/32375, RE/18/5/34216, FS/SCRF/21/32010). Dr van Beek is supported by the Scottish Imaging Network. Dr Sellers is supported by fellowships from the Michael Smith Foundation for Health Research and the Canadian Institutes of Health Research. Drs Koglin and Stephens are employees of Life Molecular Imaging GmbH, who provided reagents for radiotracer production. Dr Leipsic is supported by a Canadian Research Chair in Advanced CardioPulmonary Imaging and the Jon DeHaan Award for Innovation in Cardiology; is a consultant for Edward Lifesciences; and provides computed tomography core laboratory services to Edwards Lifesciences, Medtronic, Neovasc, Aegis, and Tendyne, for which no direct compensation is received. Dr Williams is supported by The Chief Scientist Office of the Scottish Government Health and Social Care Directorates (PCL/17/04). Dr Newby is the recipient of a Wellcome Trust Senior Investigator Award (WT103782AIA). All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

The potato psyllid Bactericera cockerelli (Šulc) (Hemiptera: Triozidae) is a pest of solanaceous crops (order Solanales), including potato ( Solanum tuberosum L.) and tomato ( S. lycopersicum L.). Feeding by high populations of nymphs causes psyllid yellows while adults and nymphs are vectors of the plant pathogen ' Candidatus Liberibacter solanacearum'. Foliar symptoms that were consistent with either ' Ca. L. solanacearum' infection or psyllid yellows were observed in 2019 on tomatillo ( Physalis ixocarpa Brot.; family Solanaceae) grown within an experimental plot located near Saltillo, Mexico. This study had three primary objectives: 9i) determine whether the foliar symptoms observed on tomatillo were associated with ' Ca. L. solanacearum' infection, (ii) identify the haplotypes of ' Ca. L. solanacearum' and potato psyllids present in the symptomatic plot, and (iii) use gut content analysis to infer the plant sources of ' Ca. L. solanacearum'-infected psyllids. Results confirmed that 71% of symptomatic plants and 71% of psyllids collected from the plants were infected with ' Ca. L. solanacearum'. The detection of ' Ca. L. solanacearum' in plants and psyllids and the lack of nymphal populations associated with psyllid yellows strongly suggests that the observed foliar symptoms were caused by ' Ca. L. solanacearum' infection. All infected plants and insects harbored the more virulent ' Ca. L. solanacearum' haplotype B but one psyllid was also coinfected with haplotype A. The potato psyllids were predominantly of the central haplotype but one psyllid was identified as the western haplotype. Molecular gut content analysis of psyllids confirmed the movement of psyllids between noncrop habitats and tomatillo and indicated that ' Ca. L. solanacearum' infection of psyllids was associated with increased plant diversity in their diet.

Aim: To examine the multimodal contrasting ability of gold-dotted magnetic nanoparticles (Au*MNPs) for magnetic resonance (MR), computed tomography (CT) and intravascular ultrasound (IVUS) imaging. Materials & methods: Au*MNPs were prepared by adapting an impregnation method, without using surface capping reagents and characterized (transmission electron microscopy, x-ray diffraction and Fourier-transform infrared spectroscopy) with their in vitro cytotoxicity assessed, followed by imaging assessments. Results: The contrast-enhancing ability of Au*MNPs was shown to be concentration-dependent across MR, CT and IVUS imaging. The Au content of the Au*MNP led to evident increases of the IVUS signal. Conclusion: We demonstrated that Au*MNPs showed concentration-dependent contrast-enhancing ability in MRI and CT imaging, and for the first-time in IVUS imaging due to the Au content. These Au*MNPs are promising toward solidifying tri-modal imaging-based theragnostics.

Dosimetry models using preclinical positron emission tomography (PET) data are commonly employed to predict the clinical radiological safety of novel radiotracers. However, unbiased clinical safety profiling remains difficult during the translational exercise from preclinical research to first-in-human studies for novel PET radiotracers. In this study, we assessed PET dosimetry data of six 18 F-labelled radiotracers using preclinical dosimetry models, different reconstruction methods and quantified the biases of these predictions relative to measured clinical doses to ease translation of new PET radiotracers to first-in-human studies. Whole-body PET images were taken from rats over 240 min after intravenous radiotracer bolus injection. Four existing and two novel PET radiotracers were investigated: [ 18 F]FDG, [ 18 F]AlF-NOTA-RGDfK, [ 18 F]AlF-NOTA-octreotide ([ 18 F]AlF-NOTA-OC), [ 18 F]AlF-NOTA-NOC, [ 18 F]ENC2015 and [ 18 F]ENC2018. Filtered-back projection (FBP) and iterative methods were used for reconstruction of PET data. Predicted and true clinical absorbed doses for [ 18 F]FDG and [ 18 F]AlF-NOTA-OC were then used to quantify bias of preclinical model predictions versus clinical measurements. Our results show that most dosimetry models were biased in their predicted clinical dosimetry compared to empirical values. Therefore, normalization of rat:human organ sizes and correction for reconstruction method biases are required to achieve higher precision of dosimetry estimates.

In September 2014, a high rate of bulb rot (5-15% depending on producer) was reported across all cultivars developing early in the storage season in the onion producing region of southwestern Idaho. Spanish yellow onion bulbs cv. Vaquero displaying tan to light brown necrotic rot were obtained. The bulb rot originated in the neck and spread to successive scales (Figure 1). In August 2015, onion cv. Redwing and Vaquero were observed to have wet necrotic lesions developing on leaves in the field (Figure 2). Margins of necrotic tissue, 1-2 cm 3 , were excised, surface sterilized, plated on water agar medium and incubated at 24°C. Hyphal growth was sub-cultured from eight strains (A- D in 2014; E-H in 2015) to fresh potato dextrose agar to obtain pure cultures. Cultures were characteristic of Fusarium species as described by Nelson et al. (1983) with the presence of microconidia formed on polyphialides with macroconidia present. Primers ITS4-A1 and ITS5 primers (White et al. 1990); EF-1 and EF-2 (O'Donnell et al. 1998); and fRPB2-5F and fRPB2-7cR (Liu et al. 1999) were used to amplify regions of the ITS, elongation factor 1-α and the second largest subunit of DNA-directed RNA polymerase II. Amplicons were sequenced and analyzed using BLAST (https://www.ncbi.nlm.nih.gov/) and in combination using Pairwise DNA Alignment and Polyphasic Identification (http://www.westerdijkinstitute.nl/Fusarium/DefaultInfo.aspx?Page=Home) as described by O'Donnell et al. 2015. Analysis indicated that these strains are Fusarium proliferatum , which is part of the F. fujikuroi species complex (O'Donnell et al. 1998). Similarity (99.5%) was observed in pairwise analyses and the polyphasic identification clustering to representative F. proliferatum strain NRRL 22944 and others. Sequences were submitted to Genbank and registered accession numbers are found in Table 1. To complete Koch's postulates, cv. Vaquero onion bulbs were surface sterilized and injected with 3 × 10 5 microconidia into the shoulder of each bulb. Five bulbs were inoculated for each isolate, placed in a mesh bag, and incubated at 30°C in the dark. Five bulbs injected with sterile water and five non-inoculated bulbs served as controls. After 14 days, each bulb was sliced vertically down the center and inspected for rot. All eight strains induced tan to light brown necrotic rot symptoms in each inoculated bulb. No symptoms were observed for the water inoculated and the non-inoculated onion bulbs. A fungus was isolated from the necrotic tissue and confirmed to be F. proliferatum as described above. Ten µl aliquots containing 1 × 10 5 microconidia of F. proliferatum strains (C, E-H) were applied to leaves in triplicate of 12-week-old onion plants (cv. Vaquero) wounded with a 21-gauge needle. Water controls were included. Within three days lesions, with light chlorosis, began to form and quickly spread on the leaves. A fungus was isolated and confirmed to be F. proliferatum as described above. This is the first extensive description and identification of F. proliferatum causing bulb rot in storage in Idaho (Mohan et al. 1997). In addition, this is the first report of the fungus causing leaf infection in the field. These findings confirm F. proliferatum as the causal agent of the high incidence of bulb rot observed in 2014 and 2015. This bulb rot continues to occur in southwestern Idaho and since the pathogen can cause leaf infections growers are encouraged to be vigilant for both leaf lesions during the growing season and bulb rot in storage.

Preclinical PET/CT is a well-established noninvasive imaging tool for studying disease development/progression and the development of novel radiotracers and pharmaceuticals for clinical applications. Despite this pivotal role, standardization of preclinical PET/CT protocols, including CT absorbed dose guidelines, is essentially nonexistent. This study (1) quantitatively assesses the variability of current preclinical PET/CT acquisition and reconstruction protocols routinely used across multiple centers and scanners; and (2) proposes acquisition and reconstruction PET/CT protocols for standardization of multicenter data, optimized for routine scanning in the preclinical PET/CT laboratory. Methods: Five different commercial preclinical PET/CT scanners in Europe and the United States were enrolled. Seven different PET/CT phantoms were used for evaluating biases on default/general scanner protocols, followed by developing standardized protocols. PET, CT, and absorbed dose biases were assessed. Results: Site default CT protocols were the following: greatest extracted Hounsfield units (HU) were 133 HU for water and -967 HU for air; significant differences in all tissue equivalent material (TEM) groups were measured. The average CT absorbed doses for mouse and rat were 72 mGy and 40 mGy, respectively. Standardized CT protocol were the following: greatest extracted HU were -77 HU for water and -990 HU for air; TEM precision improved with a reduction in variability for each tissue group. The average CT absorbed dose for mouse and rat decreased to 37 mGy and 24 mGy, respectively. Site default PET protocols were the following: uniformity was substandard in one scanner, recovery coefficients (RCs) were either over- or underestimated (maximum of 43%), standard uptake values (SUVs) were biased by a maximum of 44%. Standardized PET protocols were the following: scanner with substandard uniformity improved by 36%, RC variability decreased by 13% points, and SUV accuracy improved to 10%. Conclusion: Data revealed important quantitative biases in preclinical PET/CT and absorbed doses with default protocols. Standardized protocols showed improvements in measured PET/CT accuracy and precision with reduced CT absorbed dose across sites. Adhering to standardized protocols generates reproducible and consistent preclinical imaging datasets, thus augmenting translation of research findings to the clinic., (© 2020 by the Society of Nuclear Medicine and Molecular Imaging.)

Introduction: It has been postulated that swimming in heated indoor swimming pools in the first year of life is associated with the development of spinal deformity in children. We explored in pup mice whether exposure to certain disinfection by-products resulting from chlorination of heated pools would affect the future development of the spinal column., Methods: Mice, from birth and for 28 consecutive days, were exposed to chemicals known to be created by disinfection by-products of indoor heated swimming pools. The study made use of a body fluid analogue and a chlorine source to recreate the conditions found in municipal pools. A cohort of 51 wild-type C57B6 mice, male and female, were divided into two groups: experimental (n = 29) and controls (n = 22). 24 mice were observed for 8 months (32 weeks), with 27 culled at 4 months (16 weeks). Serial CT scanning was used to assess the spines., Results: Exposure to disinfection by-products resulted in an increase in the normal thoracic kyphotic spinal angle of the mice when compared with their controls at 10 weeks; experimental mice kyphosis range 35-82° versus 29-38° in controls. At 14 weeks the kyphosis of the experimental mice had reduced in size but never to that of the control group., Conclusion: We have demonstrated the ability to influence spinal development in pup mice through environmental factors and shown that the developmental deformity became evident only after a significant latent period., (Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.)