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A recent paper [CGT] studies the evolution of star-shaped mean convex hypersurfaces of the Euclidean space by a class of nonhomogeneous expanding curvature flows. In the present paper we consider the same problem in the real, complex and quaternionic hyperbolic spaces, investigating how the richer geometry of the ambient space affects the evolution. In every case the initial conditions are preserved and the long time existence of the flow is proven. The geometry of the ambient space influences the asymptotic behaviour of the flow: after a suitable rescaling the induced metric converges to a conformal multiple of the standard Riemannian round metric of the sphere if the ambient manifold is the real hyperbolic space, otherwise it converges to a conformal multiple of the standard sub-Riemannian metric on the odd-dimensional sphere. Finally, in every cases, we are able to construct infinitely many examples such that the limit does not have constant scalar curvature., Comment: 25 pages, comments are welcome

Purpose This study aims to examine the relation between the purchase intention of Peruvian maca and each of the following variables: Peru’s country image, maca’s product image, Peru’s country familiarity and maca’s product familiarity. Design/methodology/approach To compile primary information, a survey of closed questions was applied to students in two countries with different levels of familiarity with Peru: France and the USA. Findings There is a direct association between the studied variables in the cases where the foreign consumer has a high familiarity with Peru. Similarly, there is a positive association between maca’s product image, Peru’s country familiarity and maca’s product familiarity with the consumer purchase intention of maca from Peru in the cases where the consumer has low familiarity with Peru. Research limitations/implications The characteristics of the sample did not allow to analyze the purchase intention according to gender, age and socioeconomic level. Practical implications This study provides innovative insights to design international marketing strategies for Peruvian maca entrepreneurs and export promotion policies to policymakers, to support them to overcome the increase of the global competitive environment of maca. Social implications The paper helps maca producers and exporters to develop international marketing strategies to position their maca products in markets with high or low familiarity with Peru. Originality/value The uniqueness of this paper is based on the study of the purchase intention of agricultural products such as maca, which is a developing product available in Peru.

Background JC polyomavirus (JCV) mostly causes asymptomatic persistent renal infections but may give rise in immunosuppressed patients to neurotropic variants that replicate in the brain, causing progressive multifocal leukoencephalopathy (PML). Rearrangements in the JCV genome regulator noncoding control region (NCCR) and missense mutations in the viral capsid VP1 gene differentiate neurotropic variants from virus excreted in urine. Methods To investigate intrahost emergence of JCV neurotropic populations in PML, we deep sequenced JCV whole genome recovered from cerebrospinal fluid (CSF) and urine samples from 32 human immunodeficiency virus (HIV)–infected and non-HIV-infected PML patients at the single-molecule level. Results JCV strains distributed among 6 of 7 known genotypes. Common patterns of NCCR rearrangements included an initial deletion mostly located in a short 10-nucleotide sequence, followed by duplications/insertions. Multiple NCCR variants present in individual CSF samples shared at least 1 rearrangement, suggesting they stemmed from a unique viral population. NCCR variants independently acquired single or double PML-specific adaptive VP1 mutations. NCCR variants recovered from urine and CSF displayed opposite deletion or duplication patterns in binding sites for transcription factors. Conclusions Long-read deep sequencing shed light on emergence of neurotropic JCV populations in PML.

Background: Long COVID is a syndrome characterized by the persistence of SARS-CoV-2 infection symptoms. Among HCWs, prolonged COVID symptoms could lead to the inability to perform work tasks. The aim of this study is to investigate 35-day long-COVID (35-LC) characteristics and risk factors in a one-year period. Methods: We carried out a retrospective cohort study during the COVID-19 pandemic at University Hospital of Bari. A total of 5750 HCWs were tested for close contact with a confirmed case, in the absence of personal protective equipment, or for symptom development. Results: Each positive HCW was investigated for cardiovascular risk factors or respiratory diseases. An amount of 352 HCWs (6.1%) were infected by SARS-CoV-2, and 168 cases evolved to long COVID. The 35-LC group showed mean BMI values higher than the non-35-LC group (25.9 kg/m2 vs. 24.8 kg/m2, respectively), and this difference was significant (p-value: 0.020). Moreover, HCWs who suffered from pulmonary disease (OR = 3.7, CL 95%: 1.35–10.53, p-value = 0.007) or overweight (OR = 1.6 CL 95%: 1.05–2.56, p-value = 0.029) had an increased risk of developing 35-LC. Conclusions: Long COVID is an emerging problem for hospital managers as it may reduce the number of HCWs deployed in the fight against COVID-19. High BMI and previous pulmonary disease could be risk factors for 35-LC development in exposed HCWs.

Purpose The purpose of this paper is to analyse the different typologies of tourists that appear in cities that are in a different position within the destination life cycle. Barcelona and Lisbon, two urban destinations, with a strong growth of tourists in the last two decades, which are in advanced stages of their life cycle, and Lima, which has also expanded in the last ten years, but is in less advanced phases, have been chosen. The approach of the study is to analyse if urban tourists modify their attitude in some way in the face of the advancement of the life cycle of the city and what attitudes are expressed by them. Design/methodology/approach For this purpose, an analysis of main components was performed via factor analysis to reduce the number of dimensions of the 11 descriptive variables and the counterpart of tourist attitudes, following Schwartz’s (2006) research. From the four clusters that emerged – authenticity; innovative and cultural hard; relaxation and not innovative – four attitude variables were selected since they were considered relevant to be analysed according to the life cycle of the city: culture and entertainment; authenticity and online social exhibition; and expensive and cheap price. Findings The results obtained do not allow to straightforwardly conclude that as the life cycle of these three cities advances, the attitude evolves from culture to entertainment, from authenticity towards online social exhibition or from the most expensive to the cheapest. The tourists from Barcelona are mostly associated with entertainment, those from Lisbon are associated with culture and those from Lima are split. However, in the face of authenticity, travellers are prone to it. Regarding the price, those in Barcelona are almost divided equally, whereas those in Lisbon, and especially those in Lima, consider it to be mostly cheap. Originality/value From this study, it can be drawn that the attitude of travellers to these three cities is not conditioned by the life cycle. Globalization and digitalisation put pressure on the traveller by configuring a universal model of behaviour before the urban offer that is associated with other factors, but not with the life cycle of the city.

The purpose of this paper is to study the relationship between the (i) country image of Peru, (ii) cotton’s product image, (iii) familiarity with Peru, and (iv) cotton’s product familiarity with the purchase intention of Peruvian cotton. Survey techniques were used to collect the primary data, applying a closed question questionnaire in two samples that represent the consumers of two countries with different levels of familiarity with Peru: France and the United States. This study has found that there is a positive association between the studied variables, in at least one sample. One of the main managerial implications is that Peruvian cotton exporters could innovate their global marketing strategies using Peru’s country image to improve the positioning of Peruvian cotton in international markets. JEL classification: M31, M38, Q13. Resumen El objetivo de este artículo es analizar la asociación entre (i) la imagen país Perú, (ii) la imagen producto del algodón, (iii) la familiaridad con el Perú y (iv) la familiaridad con el producto algodón, con la intención de compra del algodón peruano. La técnica de encuesta se utilizó para recopilar información primaria, aplicando un cuestionario de preguntas cerradas a dos muestras que corresponden a los consumidores de dos países con diferentes niveles de familiaridad con Perú: Francia y Estados Unidos. Se encontró que existe una asociación positiva entre las variables estudiadas, en al menos una muestra. En efecto, los exportadores peruanos de algodón podrían innovar sus estrategias de marketing utilizando la imagen país Perú para mejorar el posicionamiento del algodón peruano en el extranjero. Resumo O objetivo deste artigo é analisar a relação entre a imagem do país do Peru, a imagem do produto de algodão, a familiaridade com o Peru e a familiaridade com o produto de algodão, com a intenção de comprar algodão do Peru. A técnica de pesquisa foi utilizada para coletar informações primarias, aplicando um questionário de perguntas fechadas em duas amostras que correspondem a consumidores em dois países com diferentes níveis de familiaridade com o Peru (França e Estados Unidos). Verificou-se uma associação positiva entre as variáveis estudadas, em pelo menos uma amostra. De fato, os exportadores de algodão peruano poderiam inovar suas estratégias de marketing usando do país para melhorar o posicionamento do algodão peruano.

BackgroundExposure to crystalline silica in dental laboratories can occur during procedures that generate suspended mineral dusts, e.g. dispersion of mixing powders, removal of castings from moulds grinding and polishing castings and porcelain, and use of silica sand for blasting. Case presentationWe report a 55-year-old male dental technician who, after about 15 years of work, began to suffer from a dry cough and dyspnoea on exertion. The operations included in his job resulted in the generation of crystalline silica, aluminium, chromium, titanium dust. The worker did not regularly wear personal protective equipment and some of the above operations were not carried out in closed circuit systems.The Chest X-ray showed diffuse micronodulation in the lung interstitium in the upper-middle lobes bilaterally and a modest left basal pleural effusion, simple spirometry showed initial small airway obstruction, High Resolution Computerized Tomography of the chest showed bilateral micronodulation of a miliariform type, with greater profusion in the upper lobes, also present in the visceral pleura, bilaterally. Histological examination showed aggregates of pigment-laden macrophages forming perivascular macules or arranged in a radial pattern around a core of sclerohyalinosis. Scanning Electron Microscopy and Energy Dispersive Spectrometry revealed several mineral particles, whose composition is characterised by the presence of aggregates of crystalline silica and metals. The ambient concentrations of total dust and its respirable fraction were all lower than the relative TLV-TWA - ACGIH, but did not negligible. ConclusionsThe above findings and a multidisciplinary assessment led to the diagnosis of mixed dust pneumoconiosis s/q with 2/2 profusion of occupational origin. This diagnosis in a dental technician was supported by environmental exposure analysis for the first time in the literature.

In recent years, graffiti writings are increasingly regarded as a form of art. However, their presence on historic building remains a vandalism and different strategies have been developed to clean or, preferably, protect the surfaces. In this study, an experimental nano-filled coating, based on fluorine resin containing SiO2 nano-particles, and two commercial products have been applied on compact and porous calcareous stones, representative of building materials used in the Mediterranean basin, and their anti-graffiti ability has been analyzed. All the tested experimental and commercial coatings exhibited high hydrophobicity and oleophobicity, thus meeting one of the basic requirements for anti-graffiti systems. The effects of staining by acrylic blu-colored spray paint and felt-tip marker were, then, assessed, the properties of the treated stone surfaces after cleaning by acetone were also investigated. Visual observations, contact angle measurements and color evaluations were performed to this aim. It was found that the protective coatings facilitated the spray paint removal, however high oleophobicity or paint repellence did not guarantee a complete cleaning. The stain from the felt-tip marker was confirmed to be extremely difficult to remove. The cleaning with a neat unconfined solvent promoted the movement of the applied polymers (and likely of the paint, as well) in the porous structure of the stone substrate.

Valls Giménez, J. F., Pipoli, G., Rita, P., & Labairu-Trenchs, I. (2020). Tourist profiles and attitudes: a comparison between cities in a different phase of the life cycle. International Journal of Tourism Cities, 6(4), 731-748. [Advanced online publication on 30 September 2019]. Doi: https://doi.org/10.1108/IJTC-02-2019-0030 Purpose: The purpose of this paper is to analyse the different typologies of tourists that appear in cities that are in a different position within the destination life cycle. Barcelona and Lisbon, two urban destinations, with a strong growth of tourists in the last two decades, which are in advanced stages of their life cycle, and Lima, which has also expanded in the last ten years, but is in less advanced phases, have been chosen. The approach of the study is to analyse if urban tourists modify their attitude in some way in the face of the advancement of the life cycle of the city and what attitudes are expressed by them. Design/methodology/approach: For this purpose, an analysis of main components was performed via factor analysis to reduce the number of dimensions of the 11 descriptive variables and the counterpart of tourist attitudes, following Schwartz’s (2006) research. From the four clusters that emerged – authenticity; innovative and cultural hard; relaxation and not innovative – four attitude variables were selected since they were considered relevant to be analysed according to the life cycle of the city: culture and entertainment; authenticity and online social exhibition; and expensive and cheap price. Findings: The results obtained do not allow to straightforwardly conclude that as the life cycle of these three cities advances, the attitude evolves from culture to entertainment, from authenticity towards online social exhibition or from the most expensive to the cheapest. The tourists from Barcelona are mostly associated with entertainment, those from Lisbon are associated with culture and those from Lima are split. However, in the face of authenticity, travellers are prone to it. Regarding the price, those in Barcelona are almost divided equally, whereas those in Lisbon, and especially those in Lima, consider it to be mostly cheap. Originality/value: From this study, it can be drawn that the attitude of travellers to these three cities is not conditioned by the life cycle. Globalization and digitalisation put pressure on the traveller by configuring a universal model of behaviour before the urban offer that is associated with other factors, but not with the life cycle of the city. authorsversion published

Summary cis-Regulatory communication is crucial in mammalian development and is thought to be restricted by the spatial partitioning of the genome in topologically associating domains (TADs). Here, we discovered that the Xist locus is regulated by sequences in the neighboring TAD. In particular, the promoter of the noncoding RNA Linx (LinxP) acts as a long-range silencer and influences the choice of X chromosome to be inactivated. This is independent of Linx transcription and independent of any effect on Tsix, the antisense regulator of Xist that shares the same TAD as Linx. Unlike Tsix, LinxP is well conserved across mammals, suggesting an ancestral mechanism for random monoallelic Xist regulation. When introduced in the same TAD as Xist, LinxP switches from a silencer to an enhancer. Our study uncovers an unsuspected regulatory axis for X chromosome inactivation and a class of cis-regulatory effects that may exploit TAD partitioning to modulate developmental decisions., Graphical Abstract, Highlights • The Tsix-TAD regulates not only Tsix but also Xist, in part via LinxP • LinxP influences choice making during random XCI by regulating Xist expression in cis • Linx transcription affects local topology but is not necessary for Xist regulation • LinxP is conserved in sequence and synteny across placental mammals, Galupa et al. uncover elements important for Xist regulation in its neighboring TAD and reveal that these elements can influence gene regulation both within and between topological domains. These findings, in a context where dynamic, developmental expression is necessary, challenge current models for TAD-based gene-regulatory landscapes.

Pangenomic studies identified distinct molecular classes for many cancers, with major clinical applications. However, routine use requires cost-effective assays. We assessed whether targeted next-generation sequencing (NGS) could call chromosomal alterations and DNA methylation status. A training set of 77 tumors and a validation set of 449 (43 tumor types) were analyzed by targeted NGS and single-nucleotide polymorphism (SNP) arrays. Thirty-two tumors were analyzed by NGS after bisulfite conversion, and compared to methylation array or methylation-specific multiplex ligation-dependent probe amplification. Considering allelic ratios, correlation was strong between targeted NGS and SNP arrays (r = 0.88). In contrast, considering DNA copy number, for variations of one DNA copy, correlation was weaker between read counts and SNP array (r = 0.49). Thus, we generated TARGOMICs, optimized for detecting chromosome alterations by combining allelic ratios and read counts generated by targeted NGS. Sensitivity for calling normal, lost, and gained chromosomes was 89%, 72%, and 31%, respectively. Specificity was 81%, 93%, and 98%, respectively. These results were confirmed in the validation set. Finally, TARGOMICs could efficiently align and compute proportions of methylated cytosines from bisulfite-converted DNA from targeted NGS. In conclusion, beyond calling mutations, targeted NGS efficiently calls chromosome alterations and methylation status in tumors. A single run and minor design/protocol adaptations are sufficient. Optimizing targeted NGS should expand translation of genomics to clinical routine.

El objetivo de este artículo es analizar la asociación entre (i) la imagen país Perú, (ii) la imagen producto del algodón, (iii) la familiaridad con el Perú y (iv) la familiaridad con el producto algodón, con la intención de compra del algodón peruano. La técnica de encuesta se utilizó para recopilar información primaria, aplicando un cuestionario de preguntas cerradas a dos muestras que corresponden a los consumidores de dos países con diferentes niveles de familiaridad con Perú: Francia y Estados Unidos. Se encontró que existe una asociación positiva entre las variables estudiadas, en al menos una muestra. En efecto, los exportadores peruanos de algodón podrían innovar sus estrategias de marketing utilizando la imagen país Perú para mejorar el posicionamiento del algodón peruano en el extranjero. The purpose of this paper is to study the relationship between the (i) country image of Peru, (ii) cotton’s product image, (iii) familiarity with Peru, and (iv) cotton’s product familiarity with the purchase intention of Peruvian cotton. Survey techniques were used to collect the primary data, applying a closed question questionnaire in two samples that represent the consumers of two countries with different levels of familiarity with Peru: France and the United States. This study has found that there is a positive association between the studied variables, in at least one sample. One of the main managerial implications is that Peruvian cotton exporters could innovate their global marketing strategies using Peru’s country image to improve the positioning of Peruvian cotton in international markets.

We classify the translators to the mean curvature flow in the three-dimensional solvable group $Sol_3$ that are invariant under the action of a one-parameter group of isometries of the ambient space. In particular we show that $Sol_3$ admits graphical translators defined on a half-plane, in contrast with a rigidity result of Shahriyari for translators in the Euclidean space. Moreover we exhibit some non-existence results., Comment: 18 pages, 7 figures, some typos have been corrected in the second version

International audience; ABMA and its analogue DABMA are two molecules of the adamantane family known to perturbate the endosomal pathway and to inhibit cell infection of several RNA and DNA viruses. Their activity against Rabies Virus (RABV) infection has already been demonstrated in vitro. (Wu et al., 2017, 2019). Here, we describe in more details their mechanism of action by comparison to Arbidol (umifenovir) and Ribavirin, two broad spectrum antivirals against emerging viruses such as Lassa, Ebola, influenza and Hantaan viruses. ABMA and DABMA, delivered 2 h pre-infection, inhibit RABV infection in vitro with an EC50 of 7.8 μM and 14 μM, respectively. They act at post-entry, by causing RABV accumulation within the endosomal compartment and DABMA specifically diminishes the expression of the GTPase Rab7a controlling the fusion of early endosomes to late endosomes or lysosomes. This may suggest that ABMA and DABMA act at different stages of the late endosomal pathway as supported by their different profile of synergy/antagonism with the fusion inhibitor Arbidol. This difference is further confirmed by the RABV mutants induced by successive passages under increasing selective pressure showing a particular involvement of the viral G protein in the DABMA inhibition while ABMA inhibition induces less mutations dispersed in the M, G and L viral proteins. These results suggest new therapeutic perspectives against rabies.