336 research outputs found

    Some factors influencing the transport of chokka squid (Loligo reynaudii dOrbigny, 1839) paralarvae off the Eastern Cape, South Africa

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    Includes abstract.Includes bibliographical references (leaves 115-126).This thesis focuses on these raised concerns and attempts to refine the modelling approach used to test the WTH. This is achieved by investigating squid paralarval survival and their specific gravity using aquarium experiments together with an improved ocean model and IBM. The influence of temperature on yolk utilization was assessed through experimentation. Tank experiments found that yolk utilization rates in chokka squid paralarvae are directly affected by temperature with faster rates at high temperature and slower rates at low temperature

    Biological aspects of the Sailfin dory Zenopsis conchifer (Lowe, 1852) caught by deep-sea trawling fishery off southern Brazil

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    Biological aspects of sailfin dory, Zenopsis conchifer, were studied from 839 individuals obtained from deep-sea commercial bottom trawling off southern Brazil at depths up to 526 m in 2002 and 2003. Samples included fish from 101 mm Lt and 15 g up to 640 mm Lt and 2,9 g. The sex-ratio was 50% at 150 mm Lt and between 300-350 mm Lt, with females outnumbering males in the remaining size classes. Reproductive activity seems to peak between July and August (austral winter). Size at attainment of 50% maturity (Lt50) was 311 mm Lt in females. The mean length and maturity of the specimens increased with depth, suggesting that larger fish concentrate in deeper waters

    Cork derived laser-induced graphene for sustainable green electronics

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    Funding text This work was financed by national funds from FCT—Fundação para a Ciência e a Tecnologia, I P, in the scope of the projects LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication—i3N. The authors acknowledge the ERC AdG Grant 787410 from the Project DIGISMART, EC Project SYNERGY H2020-WIDESPREAD-2020-5, CSA, Proposal Number 952169, and Project FOXES, FETPROACT-EIC-05-2019—FET Proactive, Proposal Number 951774. S L Silvestre, T Pinheiro and A C Marques acknowledge PhD grant SFRH/BD/149751/2019, SFRH/BD/08606/2020 and SFRH/BD/115173/2016, respectively. The authors thank Amorim Cork Composites for providing the cork samples used in this work.The demand for smart, wearable devices has been dictating our daily life with the evolution of integrated miniaturized electronics. With technological innovations, comes the impactful human footprint left on the planet’s ecosystems. Therefore, it is necessary to explore renewable materials and sustainable methodologies for industrial processes. Here, an eco-friendly approach to producing flexible electrodes based on a single-step direct laser writing is reported. A 1.06 µm wavelength fiber laser was used for the first time to produce porous three-dimensional laser-induced graphene (LIG) on an agglomerated cork substrates. The obtained material exhibits the typical Raman spectra, along with an exceptionally low sheet resistance between 7.5 and 10 ohm sq−1. LIG on cork high electrical conductivity and the friendliness of the used production method, makes it an interesting material for future technological applications. To show its applicability, the production of planar micro-supercapacitors was demonstrated, as a proof of concept. Electrochemical performance studies demonstrate that LIG interdigitated electrodes, using PVA-H2SO4 electrolyte, achieve an area capacitance of 1.35 mF cm−2 (103.63 mF cm−3) at 5 mV s−1 and 1.43 mF cm−2 (109.62 mF cm−3) at 0.1 mA cm−2. In addition, devices tested under bending conditions exhibit a capacitance of 2.20 mF cm−2 (169.22 mF cm−3) at 0.1 mA cm−2. Here, showing that these electrodes can be implemented in energy storage devices, also successfully demonstrating LIG promising application on innovative, green, and self-sustaining platforms.publishersversionpublishe

    The São Paulo shelf (SE Brazil) as a nursery ground for Doryteuthis plei (Blainville, 1823) (Cephalopoda, Loliginidae) paralarvae: a Lagrangian particle-tracking individual-based model approach

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    The São Paulo shelf ranges from ~23ºS to 25ºS, comprising nearly 622 km of shoreline. This region sustains historical landings of the tropical arrow squid Doryteuthis plei. As in other coleoid cephalopods, the broodstock dies following spawning and the continuance of the population relies exclusively upon the survival of the paralarvae, which are very sensitive to oceanographic conditions. As a first step towards the understanding of paralarval transport, the shelf area was evaluated in terms of retention/ dispersion potential. A Lagrangian particle-tracking Individual-Based Model was set up using a 3D Princeton Ocean Model model forced with in situ data obtained from July 2009 to July 2011. Neutrally buoyant particles were released every first day of every month in the model, and tracked for 30 days. The retention potential was high for particles released from the bottom all over the study area from the coast to the shelf break (200 m isobath). Offshore losses showed a marked seasonality. Regarding inshore losses, the percentage of particles beached was constant year round and smaller than offshore losses, being higher south of 24ºS. Simulation results seem to agree with present knowledge of the reproductive behaviour of the species in the regionFAPESP/BIOTA Program - 2010/50183-6FAPESP - 2010/15978-8PRCEX-USP - 12.1.895.21.4FAPESP - 2012/14140-6CNPq - 309732/2011-

    Paper-based laser-induced graphene for sustainable and flexible microsupercapacitor applications

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    Funding Information: Open access funding provided by FCT|FCCN (b-on). This work was financed by national funds from Fundação para a Ciência e a Tecnologia (FCT), I.P., in the scope of the projects LA/P/0037/2020, UIDP/50025/2020, and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication–i3N and by FEDER funds through the COMPETE 2020 Program and National Funds through Portuguese Foundation for Science and Technology under projects POCI-01–0145-FEDER-007688, UID/CTM/50025 and by ERC AdG grant from the project DIGISMART (ERC-AdG-2017, GA 787410). J.C. would like to acknowledge FCT/MCTES for his present research contract with reference CEECIND/00880/2018. R.C. acknowledges funding from i3N-FCT I.P. through the PhD Grant UI/BD/151295/2021. S. S. and T. P. also acknowledge the funding from National Foundation for Science and Technology, through the PhD Grants SFRH/BD/149751/2019 and 2020.08606.BD, respectively. Publisher Copyright: © 2022, The Author(s).Laser-induced graphene (LIG) is as a promising material for flexible microsupercapacitors (MSCs) due to its simple and cost-effective processing. However, LIG-MSC research and production has been centered on non-sustainable polymeric substrates, such as polyimide. In this work, it is presented a cost-effective, reproducible, and robust approach for the preparation of LIG structures via a one-step laser direct writing on chromatography paper. The developed strategy relies on soaking the paper in a 0.1 M sodium tetraborate solution (borax) prior to the laser processing. Borax acts as a fire-retardant agent, thus allowing the laser processing of sensitive substrates that other way would be easily destroyed under the high-energy beam. LIG on paper exhibiting low sheet resistance (30 Ω sq−1) and improved electrode/electrolyte interface was obtained by the proposed method. When used as microsupercapacitor electrodes, this laser-induced graphene resulted in specific capacitances of 4.6 mF cm−2 (0.015 mA cm−2). Furthermore, the devices exhibit excellent cycling stability (> 10,000 cycles at 0.5 mA cm−2) and good mechanical properties. By connecting the devices in series and parallel, it was also possible to control the voltage and energy delivered by the system. Thus, paper-based LIG-MSC can be used as energy storage devices for flexible, low-cost, and portable electronics. Additionally, due to their flexible design and architecture, they can be easily adapted to other circuits and applications with different power requirements. Graphical Abstract: [Figure not available: see fulltext.]publishersversionpublishe

    Epidemiologia e previsibilidade no diagnóstico clínico de ceratite microbiana no sudeste do Brasil

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    PURPOSE: The goals of the study were the following: 1) to show the epidemiology of microbial keratitis (MK) in the southeast Brazil, 2) to compare the epidemiological differences between fungal (FK) and bacterial keratitis (BK), and 3) to evaluate the frequency which ophthalmologists accurately differentiate bacterial keratitis from fungal keratitis based on clinical diagnosis. METHODS: A retrospective chart analysis of all clinically diagnosed microbial keratitis patients presenting between October, 2003 and September, 2006 was performed. Demographic features, ocular and laboratory findings, and information regarding the risk factors and clinical evolution were recorded. RESULTS: Among 118 consecutive patients with a clinical diagnosis of microbial keratitis, the positive culture rate was 61%. The predominant bacterial and fungal pathogens isolated were S. epidermidis and Fusarium spp. Prior corneal injury was more frequent among fungal keratitis than bacterial keratitis cases (p<0.0001). Coexisting systemic diseases, ocular diseases, and previous ocular surgery were more frequent among BK cases (p=0.001; p=0.001; p=0.004; respectively). The following clinical findings were more frequent in bacterial keratitis: hypopion, corneal peripheral superficial vascularisation, and ulceration area &gt;20 mm² (p<0.05). The diagnosis was predicted correctly in 81.6% of bacterial keratitis cases and in 48.1% of fungal keratitis cases. CONCLUSION: Medical judgment of microbial keratitis agent is possible based on clinical and epidemiological data, but it is more difficult for fungal infection. Thus, such data cannot be the only basis for the diagnosis of suspected microbial keratitis, but oriented clinical suspicion based on these data may be beneficial for guiding antimicrobial treatment and earlier therapy.OBJETIVO: Os objetivos deste estudo foram os seguintes: 1) mostrar epidemiologia da ceratite microbiana (CM) no sudeste do Brasil, 2) para comparar as diferenças epidemiológicas entre ceratites fúngicas (CF) e bacterianas (CB) e 3) avaliar a frequência com que os oftalmologistas distinguem com precisão ceratite fúngica de ceratite bacteriana baseado no diagnóstico clínico. MÉTODOS: Uma análise retrospectiva de todas as ceratites microbianas diagnosticadas clinicamente apresentando entre outubro de 2003 e setembro de 2006 foi realizada. As características demográficas, relativas ocular e de laboratório, e informações aos fatores de risco e evolução clínica foram registrados. RESULTADOS: Dentre 118 pacientes consecutivos com diagnóstico clínico de ceratite microbiana, a taxa de cultura positiva foi de 61%. Os patógenos predominantes de bactérias e fungos isolados foram S. epidermidis e Fusarium spp. O trauma de córnea foi mais frequente entre os casos de ceratite fúngica do que ceratite bacteriana (p<0,0001). A coexistência de doenças sistêmicas, doenças oculares e cirurgia ocular prévia foram mais frequentes entre os casos de ceratite bacteriana (p=0,001, p=0,001, p=0,004, respectivamente). Os seguintes achados clínicos foram mais frequentes em ceratite bacteriana: hipópio, vascularização periférica da córnea superficial e área de ulceração &gt;20 mm² (p<0,05). O diagnóstico foi corretamente estimado em 81,6% dos casos de CB e em 48,1% dos casos de CF. CONCLUSÃO: A presunção clínica do agente da ceratite microbiana é possível baseada em dados clínicos e epidemiológicos, mas é mais difícil para infecção fúngica. Assim, esses dados não podem ser a única base para o diagnóstico de suspeita de ceratite microbiana, mas a suspeita clínica orientada com base nesses dados pode ser benéfica para orientar o tratamento antimicrobiano e terapia precoce.CNP

    A perspective on fundamental principles, applications, and challenges

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    Funding Information: This study was financed in part by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001. The authors would like to thank the financial support given by CNPq—National Council for Scientific and Technological Development (Grant Nos. 402287/2013–4, 304044/2019–9, and 442575/2019–0), SISNANO/MCTI, Financier of Studies and Projects (FINEP) and Brazilian Agricultural Research Corp. (Embrapa) AgroNano research network. The authors would like to acknowledge the European Commission under the Project NewFun (Grant No. ERC-StG-2014, GA 640598). This work was also supported by European Research Council (ERC) Advanced Grant DIGISMART (Grant No. ERC-AdG-2017, GA 787410) and the FEDER funds through the COMPETE 2020 Program and the National Funds through the FCT—Portuguese Foundation for Science and Technology under the Project No. POCI-01–0145-FEDER-007688, Reference UID/CTM/50025; Project CHIHC, Grant No. PTDC/NAN-MAT/32558/2017; and Project BEST, Grant Nos. ALT20–03-0247-FEDER-113469 and LISBOA-01–0247-FEDER-113469. J. C. acknowledges the Santander/NOVA 2021 Collaborative Research Award—Graphene Smart Bandages for Diabetic Foot Ulcer Monitoring, Reference GSBDFULM. P. C. acknowledges BI-84-Mestre-DIGISMART and CAPES/Embrapa (Grant No. 88882.157024/2017 01) for the scholarships received. S. S. and T. P. also acknowledge the funding from National Foundation for Science and Technology, through the Ph.D. Grant Nos. SFRH/BD/149751/2019 and 2020.08606.BD. Publisher Copyright: © 2022 Author(s).Since the discovery of laser-induced graphene (LIG), significant advances have been made to obtain green LIG (gLIG) from abundant, eco-friendly, natural, and organic renewable bio-based carbon sources. Recently, some sustainable and cost-effective electronic devices have been designed with gLIG, resulting in diverse solutions to the environmental impact caused by electronic waste (e-waste). However, there are still several challenges that must be addressed regarding the widespread market implementation of gLIG-based products, from synthesis to practical applications. In this review, we focus on sustainable precursor sources, their conversion mechanisms, physical and chemical properties and applications, along with the challenges related to its implementation, showing the future opportunities and perspectives related to this promising new material. Various systems based on gLIG for energy storage, electrocatalysis, water treatment, and sensors have been reported in the literature. Additionally, gLIG has been proposed for ink formulation or incorporation into polymer matrices, to further expand its use to non-carbon-based substrates or applications for which pristine LIG cannot be directly used. In this way, it is possible to apply gLIG on diverse substrates, aiming at emerging wearable and edible electronics. Thus, this review will bring an overview of gLIG developments, in accordance with the European Green Deal, the United Nations Sustainable Development Goals and the new era of internet-of-things, which demands cost-effective electronic components based on the principles of energy efficiency and sustainable production methods.publishersversionpublishe

    Epidemiologia e previsibilidade no diagnóstico clínico de ceratite microbiana no sudeste do Brasil

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    The goals of the study were the following: 1) to show the epidemiology of microbial keratitis (MK) in the southeast Brazil, 2) to compare the epidemiological differences between fungal (FK) and bacterial keratitis (BK), and 3) to evaluate the frequency which ophthalmologists accurately differentiate bacterial keratitis from fungal keratitis based on clinical diagnosis. A retrospective chart analysis of all clinically diagnosed microbial keratitis patients presenting between October, 2003 and September, 2006 was performed. Demographic features, ocular and laboratory findings, and information regarding the risk factors and clinical evolution were recorded. Among 118 consecutive patients with a clinical diagnosis of microbial keratitis, the positive culture rate was 61%. The predominant bacterial and fungal pathogens isolated were S. epidermidis and Fusarium spp. Prior corneal injury was more frequent among fungal keratitis than bacterial keratitis cases (p20 mm2 (p20 mm2 (p<0,05). O diagnóstico foi corretamente estimado em 81,6% dos casos de CB e em 48,1% dos casos de CF. A presunção clínica do agente da ceratite microbiana é possível baseada em dados clínicos e epidemiológicos, mas é mais difícil para infecção fúngica. Assim, esses dados não podem ser a única base para o diagnóstico de suspeita de ceratite microbiana, mas a suspeita clínica orientada com base nesses dados pode ser benéfica para orientar o tratamento antimicrobiano e terapia precoc

    Prospective surveillance study of acute respiratory infections, influenza-like illness and seasonal influenza vaccine in a cohort of juvenile idiopathic arthritis patients

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    Background\ud Acute respiratory infections (ARI) are frequent in children and complications can occur in patients with chronic diseases. We evaluated the frequency and impact of ARI and influenza-like illness (ILI) episodes on disease activity, and the immunogenicity and safety of influenza vaccine in a cohort of juvenile idiopathic arthritis (JIA) patients.\ud \ud Methods\ud Surveillance of respiratory viruses was conducted in JIA patients during ARI season (March to August) in two consecutive years: 2007 (61 patients) and 2008 (63 patients). Patients with ARI or ILI had respiratory samples collected for virus detection by real time PCR. In 2008, 44 patients were immunized with influenza vaccine. JIA activity index (ACRPed30) was assessed during both surveillance periods. Influenza hemagglutination inhibition antibody titers were measured before and 30-40 days after vaccination.\ud \ud Results\ud During the study period 105 ARI episodes were reported and 26.6% of them were ILI. Of 33 samples collected, 60% were positive for at least one virus. Influenza and rhinovirus were the most frequently detected, in 30% of the samples. Of the 50 JIA flares observed, 20% were temporally associated to ARI. Influenza seroprotection rates were higher than 70% (91-100%) for all strains, and seroconversion rates exceeded 40% (74-93%). In general, response to influenza vaccine was not influenced by therapy or disease activity, but patients using anti-TNF alpha drugs presented lower seroconversion to H1N1 strain. No significant differences were found in ACRPed30 after vaccination and no patient reported ILI for 6 months after vaccination.\ud \ud Conclusion\ud ARI episodes are relatively frequent in JIA patients and may have a role triggering JIA flares. Trivalent split influenza vaccine seems to be immunogenic and safe in JIA patients.This work was supported by grants from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ 308101/2003 to Dr. Ferriani), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES 56/2007-5 to Dr Carvalho) and Fundação de Apoio ao Ensino, Pesquisa e Assistência do Hospital das Clinicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FAEPA 2534/2008 to Dr Carvalho)
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