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Benefits segmentation of a summer travel market: the case of Rocha, Uruguay
Improving the understanding of Circular Economy potential at territorial level using Systems Thinking
The definition of Circular Economy (CE) has evolved over time. It includes intervention options for reducing consumption, improving the efficiency of production, introducing recycling and reuse for materials management, including new business models geared at waste prevention. With the use of Systems Thinking and the creation of Causal Loop Diagrams (CLDs) we explore how CE strategies are related to territorial dynamics and how the outcomes of such strategies can support sustainable development. We first reviewed the literature, to identify the main drivers of change (i.e. feedback loops) triggered by CE interventions. We then applied the same systemic approach to six case studies across Europe in synergy with ESPON CIRCTER project. This allowed us to review, validate and improve the general systemic approach and further explore the role that specific territorial characteristics can play in the identification, selection and effective implementation of CE interventions. We find that some of the feedback loops emerged from the case studies are not found in the literature. On the one hand, new balancing loops have emerged, representing localized challenges to the implementation of CE strategies. On the other hand, new dynamics related to behavioural change have also emerged, which lead to self-reinforcing mechanisms in the case studies analysed, creating a stronger will for the implementation of CE interventions. The main result of our research is comprehensive CLD that can be used to assess and compare different CE strategies, fully considering the complexity of the CE and its various outcomes across social, economic and environmental indicators
Healthcare use in patients with multimorbidity
Background: The existence of multiple chronic conditions in the same patient is a public health problem increasingly recognized as relevant to health systems. Individuals with multimorbidity have additional health needs, which imply a heavy burden in healthcare use. It is estimated that between 70% and 80% of the total health expenditure is used with chronic conditions. Patients with multimorbidity are responsible for up to 75% of primary care appointments. These patients are also high hospital users, with up to 14.6 times more risk of hospitalization. Methods: This study analyses the association between healthcare use and multimorbidity in the Portuguese population aged 25-74 years old. The association between socioeconomic variables and healthcare use was studied, based on data from the first Portuguese Health Examination Survey using a logistic regression model, stratified by sex and adjusted for socioeconomic confounding variables. Results: In patients with multimorbidity, there was a greater use of primary healthcare consultations, medical or surgical specialist consultations and hospitalizations. An association was established between female, older age groups and lower educational levels, and increased healthcare use. When adjusted to socioeconomic variables, the likelihood of using healthcare services can be as high as 3.5 times, when compared to patients without chronic conditions. Conclusion: Our results show a greater healthcare use in multimorbidity patients, both in primary and hospital care. The availability of scientific evidence regarding the use of healthcare services by multimorbidity patients may support health policy changes, which could allow a more efficient management of these patients.publishersversionpublishe
Stability Constraints on Classical de Sitter Vacua
We present further no-go theorems for classical de Sitter vacua in Type II
string theory, i.e., de Sitter constructions that do not invoke
non-perturbative effects or explicit supersymmetry breaking localized sources.
By analyzing the stability of the 4D potential arising from compactification on
manfiolds with curvature, fluxes, and orientifold planes, we found that
additional ingredients, beyond the minimal ones presented so far, are necessary
to avoid the presence of unstable modes. We enumerate the minimal setups for
(meta)stable de Sitter vacua to arise in this context.Comment: 18 pages; v2: argument improved, references adde
Hepatitis B virus genotypes and resistance mutations in patients under long term lamivudine therapy: characterization of genotype G in Brazil
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Previous issue date: 2008Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Molecular. Rio de Janeiro, RJ. Brasil.Universidade Federal de Mato Grosso. Faculdade de Ciências Médicas. Núcleo de Estudos de Doenças Infecciosas e Tropicais. Cuiabá, MT, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Molecular. Rio de Janeiro, RJ. Brasil / Fundação Municipal de Saúde de Petrópolis. Hospital Alcides Carneiro. Petrópolis, RJ. Brasil.Universidade Federal do Estado do Rio de Janeiro. Hospital Universitário Gaffrée e Guinle. Rio de Janeiro, RJ, Brasil.Universidade Federal do Estado do Rio de Janeiro. Hospital Universitário Gaffrée e Guinle. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Molecular. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Molecular. Rio de Janeiro, RJ. Brasil.Lamivudine is an oral nucleoside analogue widely used for the treatment of chronic hepatitis B. The main limitation of lamivudine use is the selection of resistant mutations that increases with time of utilization. Hepatitis B virus (HBV) isolates have been classified into eight genotypes (A to H) with distinct geographical distributions. HBV genotypes may also influence pathogenic properties and therapeutic features. Here, we analyzed the HBV genotype distribution and the nature and frequency of lamivudine resistant mutations among 36 patients submitted to lamivudine treatment for 12 to 84 months
Akt inhibitors as an HIV-1 infected macrophage-specific anti-viral therapy
<p>Abstract</p> <p>Background</p> <p>Unlike CD4+ T cells, HIV-1 infected macrophages exhibit extended life span even upon stress, consistent with their <it>in vivo </it>role as long-lived HIV-1 reservoirs.</p> <p>Results</p> <p>Here, we demonstrate that PI3K/Akt inhibitors, including clinically available Miltefosine, dramatically reduced HIV-1 production from long-living virus-infected macrophages. These PI3K/Akt inhibitors hyper-sensitize infected macrophages to extracellular stresses that they are normally exposed to, and eventually lead to cell death of infected macrophages without harming uninfected cells. Based on the data from these Akt inhibitors, we were able to further investigate how HIV-1 infection utilizes the PI3K/Akt pathway to establish the cytoprotective effect of HIV-1 infection, which extends the lifespan of infected macrophages, a key viral reservoir. First, we found that HIV-1 infection activates the well characterized pro-survival PI3K/Akt pathway in primary human macrophages, as reflected by decreased PTEN protein expression and increased Akt kinase activity. Interestingly, the expression of HIV-1 or SIV Tat is sufficient to mediate this cytoprotective effect, which is dependent on the basic domain of Tat – a region that has previously been shown to bind p53. Next, we observed that this interaction appears to contribute to the downregulation of PTEN expression, since HIV-1 Tat was found to compete with PTEN for p53 binding; this is known to result in p53 destabilization, with a consequent reduction in PTEN protein production.</p> <p>Conclusion</p> <p>Since HIV-1 infected macrophages display highly elevated Akt activity, our results collectively show that PI3K/Akt inhibitors may be a novel therapy for interfering with the establishment of long-living HIV-1 infected reservoirs.</p
Health trajectories of Immigrant Children (CRIAS)-a prospective cohort study in the metropolitan area of Lisbon, Portugal
Funding Information: This research was financed by the Asylum, Integration and Migration Fund (ref.PT/2018/FAMI/350) under the Multianual Financial Framework 2014/20, by the Portuguese Foundation for Science and Technology (FCT) (ref.RESEARCH4COVID-19-065) and Global Health and Tropical Medicine (GHTM), Institute of Hygiene and Tropical Medicine (IHMT), NOVA University of Lisbon, Portugal (ref.UID/04413/2020). The extension of the cohort study is financed by the Portuguese Foundation for Science and Technology (FCT) (ref.PTDC/SAU-SER/4664/2020). Publisher Copyright: © 2022 BMJ Publishing Group. All rights reserved.Purpose The CRIAS (Health trajectories of Immigrant Children in Amadora) cohort study was created to explore whether children exposed to a migratory process experience different health risks over time, including physical health, cognitive, socioemotional and behavioural challenges and different healthcare utilisation patterns. Participants The original CRIAS was set up to include 604 children born in 2015, of whom 50% were immigrants, and their parents. Recruitment of 420 children took place between June 2019 and March 2020 at age 4/5 years, with follow-up carried out at age 5/6 years, at age 6/7 years currently under way. Findings to date Baseline data at age 4/5 years (2019-2020) suggested immigrant children to be more likely to belong to families with less income, compared with non-immigrant children. Being a first-generation immigrant child increased the odds of emotional and behavioural difficulties (adjusted OR 2.2; 95% CI: 1.06 to 4.76); more immigrant children required monitoring of items in the psychomotor development test (38.5% vs 28.3%). The prevalence of primary care utilisation was slightly higher among immigrant children (78.0% vs 73.8%), yet they received less health monitoring assessments for age 4 years. Utilisation of the hospital emergency department was higher among immigrants (53.2% vs 40.6%). Age 5 years follow-up (2020-2021) confirmed more immigrant children requiring monitoring of psychomotor development, compared with non-immigrant children (33.9% vs 21.6%). Economic inequalities exacerbated by post-COVID-19 pandemic confinement with parents of immigrant children 3.2 times more likely to have their household income decreased. Future plans Further follow-up will take place at 8, 10, 12/13 and 15 years of age. Funds awarded by the National Science Foundation will allow 900 more children from four other Lisbon area municipalities to be included in the cohort (cohort-sequential design).publishersversionpublishe
The Kondo effect in ferromagnetic atomic contacts
Iron, cobalt and nickel are archetypal ferromagnetic metals. In bulk,
electronic conduction in these materials takes place mainly through the and
electrons, whereas the magnetic moments are mostly in the narrow
-electron bands, where they tend to align. This general picture may change
at the nanoscale because electrons at the surfaces of materials experience
interactions that differ from those in the bulk. Here we show direct evidence
for such changes: electronic transport in atomic-scale contacts of pure
ferromagnets (iron, cobalt and nickel), despite their strong bulk
ferromagnetism, unexpectedly reveal Kondo physics, that is, the screening of
local magnetic moments by the conduction electrons below a characteristic
temperature. The Kondo effect creates a sharp resonance at the Fermi energy,
affecting the electrical properties of the system;this appears as a Fano-Kondo
resonance in the conductance characteristics as observed in other artificial
nanostructures. The study of hundreds of contacts shows material-dependent
lognormal distributions of the resonance width that arise naturally from Kondo
theory. These resonances broaden and disappear with increasing temperature,
also as in standard Kondo systems. Our observations, supported by calculations,
imply that coordination changes can significantly modify magnetism at the
nanoscale. Therefore, in addition to standard micromagnetic physics, strong
electronic correlations along with atomic-scale geometry need to be considered
when investigating the magnetic properties of magnetic nanostructures.Comment: 7 pages, 5 figure
Moduli Stabilisation in Heterotic Models with Standard Embedding
In this note we analyse the issue of moduli stabilisation in 4d models
obtained from heterotic string compactifications on manifolds with SU(3)
structure with standard embedding. In order to deal with tractable models we
first integrate out the massive fields. We argue that one can not only
integrate out the moduli fields, but along the way one has to truncate also the
corresponding matter fields. We show that the effective models obtained in this
way do not have satisfactory solutions. We also look for stabilised vacua which
take into account the presence of the matter fields. We argue that this also
fails due to a no-go theorem for Minkowski vacua in the moduli sector which we
prove in the end. The main ingredient for this no-go theorem is the constraint
on the fluxes which comes from the Bianchi identity.Comment: 20 pages, LaTeX; references adde
U-dual fluxes and Generalized Geometry
We perform a systematic analysis of generic string flux compactifications,
making use of Exceptional Generalized Geometry (EGG) as an organizing
principle. In particular, we establish the precise map between fluxes, gaugings
of maximal 4d supergravity and EGG, identifying the complete set of gaugings
that admit an uplift to 10d heterotic or type IIB supegravity backgrounds. Our
results reveal a rich structure, involving new deformations of 10d supergravity
backgrounds, such as the RR counterparts of the -deformation. These new
deformations are expected to provide the natural extension of the
-deformation to full-fledged F-theory backgrounds. Our analysis also
provides some clues on the 10d origin of some of the particularly less
understood gaugings of 4d supergravity. Finally, we derive the explicit
expression for the effective superpotential in arbitrary N = 1 heterotic or
type IIB orientifold compactifications, for all the allowed fluxes.Comment: 58 pages, 6 table
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