510 research outputs found
Mocarts: a lightweight radiation transport simulator for easy handling of complex sensing geometries
In functional neuroimaging (fNIRS), elaborated sensing geometries pairing multiple light sources and detectors arranged over the tissue surface are needed. A variety of software tools for probing forward models of radiation transport in tissue exist, but their handling of sensing geometries and specification of complex tissue architectures is, most times, cumbersome. In this work, we introduce a lightweight simulator, Monte Carlo Radiation Transport Simulator (MOCARTS) that attends these demands for simplifying specification of tissue architectures and complex sensing geometries. An object-oriented architecture facilitates such goal. The simulator core is evolved from the Monte Carlo Multi-Layer (mcml) tool but extended to support multi-channel simulations. Verification against mcml yields negligible error (RMSE~4-10e-9) over a photon trajectory. Full simulations show concurrent validity of the proposed tool. Finally, the ability of the new software to simulate multi-channel sensing geometries and to define biological tissue models in an intuitive nested-hierarchy way are exemplified
Recommended from our members
Planning for Climate Resilient Barangays in the Philippines: The Case of Barangay Tumana in Marikina City, Metro Manila
The Philippines is among the countries most threatened by climate change. This combined with other human and developmental factors compounds the challenge that barangays, the smallest political and administrative units in the country, face: to build and scale-up local resilience. This paper presents the case of Barangay Tumana in Marikina City, Philippines, the second most populated barangay in the city and the most devastated when Typhoon Ondoy (international name: Ketsana) hit the country in 2009.
The study examines key hazards and elements of the communities in Barangay Tumana that contribute to its susceptibility to climate-related impacts, using the definition of the United Nations Framework Convention on Climate Change (UNFCCC) to frame the process of analysis. In particular, it characterizes the biophysical/environmental risks and socioeconomic/demographic vulnerabilities of the communities (exposure and sensitivity elements) in Barangay Tumana that can be addressed through planning in order to further community resilience and enhance long-term quality of life (Ensor, and Berger, 2009). These risks and vulnerabilities are established through various quantitative and qualitative methods of data gathering and analysis, including questionnaire surveys, key informant interviews, Geographic Information System (GIS) analysis, reviews of key local documents and related literature, and a multi-stakeholder validation and consultation. Policy options to build barangay resilience in the context of climate change are then recommended
Kon-tiki/Perdido enhances PS2 integrin adhesion and localizes its ligand, Thrombospondin, in the myotendinous junction.
Cell-extracellular matrix adhesion is mediated by cell receptors, mainly integrins and transmembrane proteoglycans, which can functionally interact. How these receptors are regulated and coordinated is largely unknown and key to understand cell adhesion in development. We show that the conserved transmembrane proteoglycan Kon-tiki/Perdido (Kon) interacts with αPS2βPS integrin to mediate muscle-tendon adhesion. Double mutant embryos for kon and inflated show a synergistic increase in muscle detachment. Furthermore, Kon modulates αPS2βPS signaling at the muscle attachment, since P-Fak is reduced in kon mutants. This reduction in integrin signaling can be rescued by the expression of a truncated Kon protein containing the transmembrane and extracellular domains, suggesting that these domains are sufficient to mediate this signaling. We show that these domains are sufficient to properly localize the αPS2βPS ligand, Thrombospondin, to the muscle attachment, and to partially rescue Kon dependent muscle-tendon adhesion. We propose that Kon can engage in a protein complex with αPS2βPS and enhance integrin-mediated signaling and adhesion by recruiting its ligand, which would increase integrin-binding affinity to the extracellular matrix, resulting in the consolidation of the myotendinous junction.Ramón y Cajal program and the Universidad Pablo de
Olavide. Research was funded by the Ministerio de Economıa y Competitividad ́
(Spanish Ministry of Science and Innovation) (BFU2008-036550, BFU2011-26745).
Proyecto de Excelencia of the Consejerıa de Econom ́ ıa, ́
Innovación, Ciencia y Empleo, Junta de Andalucıa (PO9-CVI-5058). A.G.E.-Z. and ́ the Ministerio de Ciencia e Innovación
(Spanish Ministry of Science and Innovation) (BFU2008-036550, BFU2011-26745)
Socio-Economic Status, Territory and Political Participation in Twenty-First-Century Mexico
This article is built on the reflections that the authors have had during their latest research on political participation in several municipalities of Mexico. Thus, based on the ethnographies conducted between 2006 and 2016, mainly in the town of Xico (Veracruz state), we set up as analyzing unities specific political interactions (including patronizing) among Mexican citizens within the five types recognized by Social Sciences: voting, campaigning, contacting political officials, working on public affairs and talking about politics. On this basis, we explore the articulation of the aforementioned interactions and, more specifically, of the roles adopted by the interacting citizens as identity markers linking these people in a highlighted way with a series of socio?economic and socio?territorial features, dimensions that, ultimately, turn out inseparable from the existing power relations in the local societies. In conclusion, we are of the opinion that, together with indicators of income, education, professional category or living nearby territory, it can be affirmed that the political behavior in Mexico is shown as both socio?economic indicator and socio?territorial belonging not because parties represent interests of class, but because there are well defined spheres of political behavior depending on the socio?economic stratum and the socio?territorial belonging of the individual
Nanomedicines for the delivery of antimicrobial peptides (AMPs)
Microbial infections are still among the major public health concerns since several yeasts and fungi, and other pathogenic microorganisms, are responsible for continuous growth of infections and drug resistance against bacteria. Antimicrobial resistance rate is fostering the need to develop new strategies against drug-resistant superbugs. Antimicrobial peptides (AMPs) are small peptide-based molecules of 5–100 amino acids in length, with potent and broad-spectrum antimicrobial properties. They are part of the innate immune system, which can represent a minimal risk of resistance development. These characteristics contribute to the description of these molecules as promising new molecules in the development of new antimicrobial drugs. However, efforts in developing new medicines have not resulted in any decrease of drug resistance yet. Thus, a technological approach on improving existing drugs is gaining special interest. Nanomedicine provides easy access to innovative carriers, which ultimately enable the design and development of targeted delivery systems of the most efficient drugs with increased efficacy and reduced toxicity. Based on performance, successful experiments, and considerable market prospects, nanotechnology will undoubtedly lead a breakthrough in biomedical field also for infectious diseases, as there are several nanotechnological approaches that exhibit important roles in restoring antibiotic activity against resistant bacteria.Elena Sanchez-Lopez belongs to 2017SGR-1477. Elena Sanchez-Lopez, Marta Espina and Maria L. GarciaacknowledgethesupportfromtheInstituteofNanoscienceandNanotechnology(ART2018project). Eliana B. Souto acknowledges the Portuguese Science and Technology Foundation (FCT/MCT) and European Funds (PRODER/COMPETE) for the projects M-ERA-NET-0004/2015-PAIRED and UIDB/04469/2020 (strategic fund), co-funded by FEDER, under the partnership Agreement PT2020. Maria C. Teixeira wishes to acknowledge FCT for the individual fellowship (PD/BDE/135086/2017).info:eu-repo/semantics/publishedVersio
Família é afetos: 'a opção sexual é coisa dele'. Discursos de filhos com pais não heteros
This qualitative study makes a contribution to the interdisciplinary field of study about childhood and family and adopts a socio-anthropological approach. Analyzing the content of 8 interviews/conversations, we have elicited the meaning of family from four children whose parents name themselves as not heterosexual, all of them living in the metropolitan region of Recife-PE- Brazil. We have identified the construction and constitution of a familiar context and we have analyzed some elements that characterize the relationship between children and parents. Family is primarily defined by children as a social construction, based on affection, without considering the sexual identity of those who develop the parenthood.This qualitative study makes a contribution to the interdisciplinary field of study about childhood and family and adopts a socio-anthropological approach. Analyzing the content of 8 interviews/conversations, we have elicited the meaning of family from four children whose parents name themselves as not heterosexual, all of them living in the metropolitan region of Recife-PE- Brazil. We have identified the construction and constitution of a familiar context and we have analyzed some elements that characterize the relationship between children and parents. Family is primarily defined by children as a social construction, based on affection, without considering the sexual identity of those who develop the parenthood.Este estudo qualitativo busca contribuir para o campo interdisciplinar dos estudos sobre infância e família, e adota uma perspectiva de análise sócio-antropológica. Analisando o conteúdo de oito entrevistas/conversas, nós obtivemos informações sobre os significados de família para crianças cujos pais se autonomeavam como não-heterossexuais, todos eles vivendo na região metropolitana de Recife (PE) -Brasil. Identificamos a construção e constituição do contexto familiaranalisando alguns elementos que caracterizam a relação entre as crianças e os pais. A família é definida pelas crianças principalmente como uma construção social com base no afeto, sem considerar a identidade sexual daqueles que exercem a paternidad
PTRF acts as an adipokine contributing to adipocyte dysfunctionality and ectopic lipid deposition
Adipose tissue (AT) expands under obesogenic conditions. Yet, when the growth exceeds a certain limit, AT becomes dysfunctional and surplus lipids start depositing ectopically. Polymerase I and transcription release factor (PTRF) has been proposed as a mechanism leading to a dysfunctional AT by decreasing the adipogenic potential of human adipocyte precursors. However, whether or not PTRF can be secreted by the adipocytes into the bloodstream is not yet known. For this work, PTRF presence was investigated in plasma. We also produced a recombinant PTRF (rPTRF) and examined its impact on the functional interactions between the adipocyte and the hepatocyte in vitro. We demonstrated that PTRF can be found in human plasma, and is at least in part, carried by exosomes. In vitro treatment with rPTRF increased the hypertrophy and senescence of 3T3-L1 adipocytes. In turn, those rPTRF-treated adipocytes increased lipid accumulation in hepatocytes. Lastly, we found a positive correlation between circulating PTRF and the concentration of PTRF in the visceral fat depot. All these findings point toward the presence of an enlarged and dysfunctional visceral adipose tissue which secretes PTRF. This circulating PTRF behaves as an adipokine and may partially contribute to the well-known detrimental effects of visceral fat accumulation
Surface functionalization of PLGA nanoparticles to increase transport across the BBB for Alzheimers disease
Alzheimers disease (AD) is a chronic neurodegenerative disorder that accounts for about 60% of all diagnosed cases of dementia worldwide. Although there are currently several drugs marketed for its treatment, none are capable of slowing down or stopping the progression of AD. The role of the blood-brain barrier (BBB) plays a key role in the design of a successful treatment for this neurodegenerative disease. Nanosized particles have been proposed as suitable drug delivery systems to overcome BBB with the purpose of increasing bioavailability of drugs in the brain. Biodegradable poly (lactic-co-glycolic acid) nanoparticles (PLGA-NPs) have been particularly regarded as promising drug delivery systems as they can be surface-tailored with functionalized molecules for site-specific targeting. In this review, a thorough discussion about the most recent functionalization strategies based on PLGA-NPs for AD and their mechanisms of action is provided, together with a description of AD pathogenesis and the role of the BBB in brain targeting.A.C. [Amanda Cano] acknowledges the support of the Spanish Ministry of Science, Innovation and Universities under the grant Juan de la Cierva (FJC2018-036012-I). Authors acknowledge the support of the Spanish Ministry of Economy and Competitiveness under the project SAF2017-84283-R; Biomedical Research Networking Centre in Neurodegenerative Diseases (CIBERNED, CB06/05/0024) and Portuguese Science and Technology Foundation (FCT) for the strategic fund (UIDB/04469/2020).info:eu-repo/semantics/publishedVersio
Sirtuins and SIRT6 in carcinogenesis and in diet
Sirtuins are a highly conserved family of nicotinamide adenine dinucleotide (NAD)-dependent protein lysine modifying enzymes. They are key regulators for a wide variety of cellular and physiological processes such as cell proliferation, differentiation, DNA damage and stress response, genome stability, cell survival, metabolism, energy homeostasis, organ development and aging. Aging is one of the major risk factors of cancer, as many of the physiological mechanisms and pathologies associated with the aging process also contribute to tumor initiation, growth and/or metastasis. This review focuses on one the mammalian sirtuins, SIRT6, which has emerged as an important regulator of longevity and appears to have multiple biochemical functions that interfere with tumor development and may be useful in cancer prevention and for site-specific treatment. The recent evidence of the role of SIRT6 in carcinogenesis is also discussed, focusing on the potential use of SIRT6 modulators in cancer nanomedicine.The authors would like to thank the financial support received from the Portuguese Science and Technology Foundation (FCT/MCT) and from European Funds (PRODER/COMPETE) under the project reference M-ERA-NET/0004/2015-PAIRED, co-financed by FEDER, under the Partnership Agreement PT2020. MCT wishes to acknowledge FCT and Dendropharma - Investigação E Serviços De Intervenção Farmacêutica, Sociedade Unipessoal Lda, for the individual fellowship (PDE/00017/2013). The Institute of Nanoscience and Nanotechnology is also acknowledged (project ART2018)
- …