Modeling of Ion/Target Interactions in Plasma Facing Components of Fusion Reactor

Nuclear fusion is a promising source of clean energy that can be one of the key future suppliers of the world’s increasing power demand. One of today’s main challenges faced by scientists and engineers regarding nuclear reactors is to design plasma-facing components (PFCs) that can withstand extreme conditions of temperature, pressure, and ions/particles irradiation. Material evolution and damage of PFCs are strongly related to the bombardment and diffusion processes of ions resulting from fusion fuel, i.e., deuterium and tritium and reaction products, i.e., helium. However, work is still needed in order to understand fuel diffusion in the presence of helium effects and damage produced in heterogeneous media of potential PFCs. This study simulates the diffusion of atoms in an alloy of changing solute concentration in an environment similar to that of a nuclear fusion reactor. The diffusion equation was solved numerically while taking into account the “potential diffusion” present in heterogeneous materials, as it was described analytically in recent studies. The solution was implemented in Fortran 90 code using SRIM software as an input generator and taking parameters found in literature. Our results show that heterogeneous membranes can greatly shift the deuterium concentration profile towards the vanadium back surface, increasing the material\u27s permeability. These outcomes suggest that vanadium alloys with heterogeneous solute concentration distribution should be empirically analyzed in order to understand how these concentration shifts affect material properties and fuel retention

Quantitative Tissue Spectroscopy of Near Infrared Fluorescent Nanosensor Implants

Implantable, near infrared (nIR) fluorescent nanosensors are advantageous for in vivo monitoring of biological analytes since they can be rendered selective for particular target molecule while utilizing their unique optical properties and the nIR tissue transparency window for information transfer without an internal power source or telemetry. However, basic questions remain regarding the optimal encapsulation platform, geometrical properties, and concentration ranges required for effective signal to noise ratio through biological tissue. In this work, we systematically explore these variables quantitatively to optimize the performance of such optical nanosensors for biomedical applications. We investigate both alginate and polyethylene glycol (PEG) as model hydrogel systems, encapsulating d(GT)[subscript 15] ssDNA-wrapped single walled carbon nanotubes (SWNT) as model fluorescent nanoparticle sensors, responsive to riboflavin. Hydrogel sensors implanted 0.5 mm into thick tissue samples cause 50% reduction of initial fluorescence intensity, allowing an optical detection limit of 5.4 mm and 5.1 mm depth in tissue for alginate and PEG gels, respectively, at a SWNT concentration of 10 mg L−1, and 785 nm laser excitation of 80 mW and 30 s exposure. These findings are supported with in vivo nIR fluorescent imaging of SWNT hydrogels implanted subcutaneously in mice. For the case of SWNT, we find that the alginate system is preferable in terms of emission intensity, sensor response, rheological properties, and shelf life.National Institutes of Health (U.S.) (T32 Training Grant in Environmental Toxicology ES007020)National Cancer Institute (U.S.) (Grant P01 CA26731)National Institute of Environmental Health Sciences (Grant P30 ES002109)Arnold and Mabel Beckman Foundation (Young Investigator Award)National Science Foundation (U.S.) (Presidential Early Career Award for Scientists and Engineers)MIT-Technion FellowshipSamsung Scholarship FoundationSanofi Aventis (Firm) (Biomedical Innovation Grant

Cultivando saberes: hortas familiares, segurança alimentar e práticas educativas no planalto serrano catarinense

Este artigo analisa o processo de implementação de propostas de Agricultura Urbana no município de Curitibanos/SC. A partir de 2013 o PET: Ciências Rurais (UFSC) inicia o projeto na perspectiva de duplicar a tecnologia social proposta pelo LECERA/CCA/UFSC, que tem como um de seus objetivos o incentivo a formação de hortas em espaços urbanos. O trabalho iniciou pelo bairro São Luiz em parceria com organizações da sociedade civil, entidades governamentais e religiosas, foi ampliado em 2016 com atividades na APAE/Curitibanos. Esse projeto pauta-se em experiências solidárias articulando práticas e incentivos a realização de hortas nas famílias e ações educativas através de hortas e jardins terapêuticos. Desta forma contribui para produção alimentar familiar, com inferências na educação alimentar e nutricional, bem como, delineando espaços culturais e interacionais entre os jovens e suas famílias. Enquanto resultado observa-se a contribuição para processos de inclusão social, saúde, qualidade de vida e cidadania, com a consequente valorização do conhecimento, saberes e fazeres na produção alimentar e nas práticas de economia solidária. É nesse sentido que muitas experiências envolvendo a construção de hortas comunitárias e de agricultura urbana são realizados

Anti-reflection coating with mullite and Duroid for large-diameter cryogenic sapphire and alumina optics

We developed a broadband two-layer anti-reflection (AR) coating for use on a sapphire half-wave plate (HWP) and an alumina infrared (IR) filter for the cosmic microwave background (CMB) polarimetry. Measuring the faint CMB B-mode signals requires maximizing the number of photons reaching the detectors and minimizing spurious polarization due to reflection with an off-axis incident angle. Sapphire and alumina have high refractive indices of 3.1 and are highly reflective without an AR coating. This paper presents the design, fabrication, quality control, and measured performance of an AR coating using thermally-sprayed mullite and Duroid 5880LZ. This technology enables large optical elements with diameters of 600 mm. We also present a newly developed thermography-based nondestructive quality control technique, which is key to assuring good adhesion and preventing delamination when thermal cycling. We demonstrate the average reflectance of about 2.6% (0.9%) for two observing bands centered at 90/150 (220/280) GHz. At room temperature, the average transmittance of a 105 mm square test sample at 220/280 GHz is 83%, and it will increase to 90% at 100 K, attributed to reduced absorption losses. Therefore, our developed layering technique has proved effective for 220/280 GHz applications, particularly in addressing dielectric loss concerns. This AR coating technology has been deployed in the cryogenic HWP and IR filters of the Simons Array and the Simons observatory experiments and applies to future experiments such as CMB-S4

Avaliação in silico de derivados naftoquinônicos frente à NSP9 do SARS-COV-2 / In silico evaluation of naphtoquinonic derivatives against SARS-COV-2 NSP9

O SARS-CoV-2 é o agente etiológico da COVID-19, que representa uma emergência de saúde global. A proteína Nsp9 Replicase é crítica para a maquinaria de RNA replicase e parece desempenhar um papel fundamental na transcrição do genoma do RNA do SARS-CoV-2. Dessa forma, essa proteína não estrutural pode ser um alvo potencial para a pesquisa de fármacos capazes de inibir a progressão viral. Em vista das poucas opções terapêuticas disponíveis para essa doença, buscou-se planejar, por meio de triagem virtual, derivados naftoquinônicos com potencial de inibição da Nsp9 Replicase e que apresentassem perfil físico-químicos ideais para candidatos a fármacos. Foram planejados 6 derivados, onde apenas 2 (D5 e D6) obtiveram um perfil de complementariedade com a enzima Nsp9. Quanto ao perfil físico-químico, D5 atendem à Regrado dos 5 Lipinski. Adicionalmente, as etapas para a sua síntese são simples e de custo acessível, tornando viável sua produção para testes in vitro e in vivo. Sendo assim, estre trabalho traz uma proposta de nova molécula de fácil obtenção e características farmacocinéticas apropriadas e que apresenta potencial de inibição de uma importante proteína de SARS-CoV-2, responsável por um dos maiores problemas de saúde pública da era moderna

Development of the Low Frequency Telescope Focal Plane Detector Modules for LiteBIRD

LiteBIRD is a JAXA-led strategic large-class satellite mission designed to measure the polarization of the cosmic microwave background and Galactic foregrounds from 34 to 448 GHz across the entire sky from L2 in the late 2020s. The scientific payload includes three telescopes which are called the low-, mid-, and high-frequency telescopes each with their own receiver that covers a portion of the mission's frequency range. The low frequency telescope will map synchrotron radiation from the Galactic foreground and the cosmic microwave background. We discuss the design, fabrication, and characterization of the low-frequency focal plane modules for low-frequency telescope, which has a total bandwidth ranging from 34 to 161 GHz. There will be a total of 4 different pixel types with 8 overlapping bands to cover the full frequency range. These modules are housed in a single low-frequency focal plane unit which provides thermal isolation, mechanical support, and radiative baffling for the detectors. The module design implements multi-chroic lenslet-coupled sinuous antenna arrays coupled to transition edge sensor bolometers read out with frequency-domain mulitplexing. While this technology has strong heritage in ground-based cosmic microwave background experiments, the broad frequency coverage, low optical loading conditions, and the high cosmic ray background of the space environment require further development of this technology to be suitable for LiteBIRD. In these proceedings, we discuss the optical and bolometeric characterization of a triplexing prototype pixel with bands centered on 78, 100, and 140 GHz.Comment: SPIE Astronomical Telescope + Instrumentation (AS22

Caracterização química dos extratos in natura das folhas de Arrabidaea chica Verlot e avaliação do potencial regenerativo através de testes in vitro e in vivo em fibroblastos : Chemical characterization of in natura extracts from the leaves of Arrabidaea chica Verlot and evaluation of the regenerative potential through in vitro and in vivo tests in fibroblasts

A biodiversidade da flora brasileira é bastante vasta e representa um imenso potencial de utilização econômica pela indústria farmacêutica e cosmética. Dentre as espécies vegetais catalogadas no Brasil, a Arrabidaea chica Verlot, pertencente à família Bignoniaceae, conhecida popularmente pelos nomes de pariri, cipó-pau ou crajiru, encontra-se listada na Relação Nacional de Plantas Medicinais de Interesse ao SUS (RENISUS) para estudo e viabilidade como cicatrizante e tratamento de ulcerações diabéticas. Este trabalho avaliou os extratos de folhas de Arrabidaea chica para fins de identificação de compostos ativos e demonstrou que o extrato foi capaz de reduzir as lesões na pele 13% em apenas dois dias de aplicação tópico, além de demonstrar mediante ensaio in vitro de indução de crescimento de fibroblastos. Com a caracterização química dos extratos, observou-se a possível presença de compostos do grupo de flavonoides e antocianinas como quercetina e 3-desoxiantocianidina, respectivamente. Nenhuma das amostras apresentou citotoxicidade nas concentrações testadas, assim como não teve diferença significativa na quantidade de células nos diferentes tratamentos no ensaio de proliferação celular