822 research outputs found

    Peritoneal fluid modulates the sperm acrosomal exocytosis induced by N-acetylglucosaminyl neoglycoprotein

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    The effect of peritoneal fluid (PF) on the human sperm acrosome reaction (AR) was tested. Sperm was pre-incubated with PF and the AR was induced by calcium ionophore A23187 and a neoglycoprotein bearing N-acetylglycosamine residues (NGP). The AR induced by calcium ionophore was inhibited 40% by PF from controls (PFc) and 50% by PF from the endometriosis (PFe) group, but not by PF from infertile patients without endometriosis (PFi). No significant differences were found in the spontaneous AR. When the AR was induced by NGP, pre-incubation with PFc reduced (60%) the percentage of AR, while PFe and PFi caused no significant differences. The average rates of acrosome reactions obtained in control, NGP- and ionophore-treated sperm showed that NGP-induced exocytosis differed significantly between the PFc (11%) and PFe/PFi groups (17%), and the ionophore-induced AR was higher for PFi (33%) than PFc/PFe (25%). The incidence of the NGP-induced AR was reduced in the first hour of pre-incubation with PFc and remained nearly constant throughout 4 h of incubation. The present data indicate that PF possesses a protective factor which prevents premature AR.Hospital de Clínicas de Porto AlegreUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

    In vitro and in vivo ocular biocompatibility of electrospun poly(ɛ-caprolactone) nanofibers.

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    Biocompatibility is a requirement for the development of nanofibers for ophthalmic applications. In this study, nanofibers were elaborated using poly(ε-caprolactone) via electrospinning. The ocular biocompatibility of this material was investigated. MIO-M1 and ARPE-19 cell cultures were incubated with nanofibers and cellular responses were monitored by viability and morphology. The in vitro biocompatibility revealed that the nanofibers were not cytotoxic to the ocular cells. These cells exposed to the nanofibers proliferated and formed an organized monolayer. ARPE-19 and MIO-M1 cells were capable of expressing GFAP, respectively, demonstrating their functionality. Nanofibers were inserted into the vitreous cavity of the rat's eye for 10days and the in vivo biocompatibility was investigated using Optical Coherence Tomography (OCT), histology and measuring the expression of pro-inflammatory genes (IL-1β, TNF-α, VEGF and iNOS) (real-time PCR). The OCT and the histological analyzes exhibited the preserved architecture of the tissues of the eye. The biomaterial did not elicit an inflammatory reaction and pro-inflammatory cytokines were not expressed by the retinal cells, and the other posterior tissues of the eye. Results from the biocompatibility studies indicated that the nanofibers exhibited a high degree of cellular biocompatibility and short-term intraocular tolerance, indicating that they might be applied as drug carrier for ophthalmic use

    Adaptive path planning for fusing rapidly exploring random trees and deep reinforcement learning in an agriculture dynamic environment UAVs

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    Unmanned aerial vehicles (UAV) are a suitable solution for monitoring growing cultures due to the possibility of covering a large area and the necessity of periodic monitoring. In inspection and monitoring tasks, the UAV must find an optimal or near-optimal collision-free route given initial and target positions. In this sense, path-planning strategies are crucial, especially online path planning that can represent the robot’s operational environment or for control purposes. Therefore, this paper proposes an online adaptive path-planning solution based on the fusion of rapidly exploring random trees (RRT) and deep reinforcement learning (DRL) algorithms applied to the generation and control of the UAV autonomous trajectory during an olive-growing fly traps inspection task. The main objective of this proposal is to provide a reliable route for the UAV to reach the inspection points in the tree space to capture an image of the trap autonomously, avoiding possible obstacles present in the environment. The proposed framework was tested in a simulated environment using Gazebo and ROS. The results showed that the proposed solution accomplished the trial for environments up to 300 m3 and with 10 dynamic objects.The authors would like to thank the following Brazilian Agencies CEFET-RJ, CAPES, CNPq, and FAPERJ. The authors also want to thank the Research Centre in Digitalization and Intelligent Robotics (CeDRI), Instituto Politécnico de Bragança–IPB (UIDB/05757/2020 and UIDP/05757/2020), the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI, and Laboratório Associado para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC) and IPB, Portugal. This work was carried out under the Project “OleaChain: Competências para a sustentabilidade e inovação da cadeia de valor do olival tradicional no Norte Interior de Portugal” (NORTE-06-3559-FSE-000188), an operation to hire highly qualified human resources, funded by NORTE 2020 through the European Social Fund (ESF).info:eu-repo/semantics/publishedVersio

    Unified dark energy models : a phenomenological approach

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    A phenomenological approach is proposed to the problem of universe accelerated expansion and of the dark energy nature. A general class of models is introduced whose energy density depends on the redshift zz in such a way that a smooth transition among the three main phases of the universe evolution (radiation era, matter domination, asymptotical de Sitter state) is naturally achieved. We use the estimated age of the universe, the Hubble diagram of Type Ia Supernovae and the angular size - redshift relation for compact and ultracompact radio structures to test whether the model is in agreement with astrophysical observation and to constrain its main parameters. Although phenomenologically motivated, the model may be straightforwardly interpreted as a two fluids scenario in which the quintessence is generated by a suitably chosen scalar field potential. On the other hand, the same model may also be read in the context of unified dark energy models or in the framework of modified Friedmann equation theories.Comment: 12 pages, 10 figures, accepted for publication on Physical Review

    Cooperative heterogeneous robots for autonomous insects trap monitoring system in a precision agriculture scenario

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    The recent advances in precision agriculture are due to the emergence of modern robotics systems. For instance, unmanned aerial systems (UASs) give new possibilities that advance the solution of existing problems in this area in many different aspects. The reason is due to these platforms’ ability to perform activities at varying levels of complexity. Therefore, this research presents a multiple-cooperative robot solution for UAS and unmanned ground vehicle (UGV) systems for their joint inspection of olive grove inspect traps. This work evaluated the UAS and UGV vision-based navigation based on a yellow fly trap fixed in the trees to provide visual position data using the You Only Look Once (YOLO) algorithms. The experimental setup evaluated the fuzzy control algorithm applied to the UAS to make it reach the trap efficiently. Experimental tests were conducted in a realistic simulation environment using a robot operating system (ROS) and CoppeliaSim platforms to verify the methodology’s performance, and all tests considered specific real-world environmental conditions. A search and landing algorithm based on augmented reality tag (AR-Tag) visual processing was evaluated to allow for the return and landing of the UAS to the UGV base. The outcomes obtained in this work demonstrate the robustness and feasibility of the multiple-cooperative robot architecture for UGVs and UASs applied in the olive inspection scenario.The authors would like to thank the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021). In addition, the authors would like to thank the following Brazilian Agencies CEFET-RJ, CAPES, CNPq, and FAPERJ. In addition, the authors also want to thank the Research Centre in Digitalization and Intelligent Robotics (CeDRI), Instituto Politécnico de Braganca (IPB) - Campus de Santa Apolonia, Portugal, Laboratório Associado para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC), Portugal, INESC Technology and Science - Porto, Portugal and Universidade de Trás-os-Montes e Alto Douro - Vila Real, Portugal. This work was carried out under the Project “OleaChain: Competências para a sustentabilidade e inovação da cadeia de valor do olival tradicional no Norte Interior de Portugal” (NORTE-06-3559-FSE-000188), an operation used to hire highly qualified human resources, funded by NORTE 2020 through the European Social Fund (ESF).info:eu-repo/semantics/publishedVersio

    Angiotensin-converting enzyme inhibitor protects against cisplatin nephrotoxicity by modulating kinin B1 receptor expression and aminopeptidase P activity in mice

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    Cisplatin is a highly effective chemotherapeutic agent. However, its use is limited by nephrotoxicity. Enalapril is an angiotensin I-converting enzyme inhibitor used for the treatment of hypertension, mainly through the reduction of angiotensin II formation, but also through the increase of kinins half-life. Kinin B1 receptor is associated with inflammation and migration of immune cells into the injured tissue. We have previously shown that the deletion or blockage of kinin B1 and B2 receptors can attenuate cisplatin nephrotoxicity. In this study, we tested enalapril treatment as a tool to prevent cisplatin nephrotoxicity. Male C57Bl/6 mice were divided into 3 groups: control group; cisplatin (20 mg/kg i.p) group; and enalapril (1.5 mg;kg i.p) + cisplatin group. The animals were treated with a single dose of cisplatin and euthanized after 96 h. Enalapril was able to attenuate cisplatin-induced increase in creatinine and urea, and to reduce tubular injury and upregulation of apoptosis-related genes, as well as inflammatory cytokines in circulation and kidney. The upregulation of B1 receptor was blocked in enalapril + cisplatin group. Carboxypeptidase M expression, which generates B1 receptor agonists, is blunted by cisplatin + enalapril treatment. The activity of aminopeptidase P, a secondary key enzyme able to degrade kinins, is restored by enalapril treatment. These findings were confirmed in mouse renal epithelial tubular cells, in which enalaprilat (5 μM) was capable of decreasing tubular injury and inflammatory markers. We treated mouse renal epithelial tubular cells with cisplatin (100 μM), cisplatin+enalaprilat and cisplatin+enalaprilat+apstatin (10 μM). The results showed that cisplatin alone decreases cell viability, cisplatin plus enalaprilat is able to restore cell viability, and cisplatin plus enalaprilat and apstatin decreases cell viability. In the present study, we demonstrated that enalapril prevents cisplatin nephrotoxicity mainly by preventing the upregulation of B1 receptor and carboxypeptidase M and the increased concentrations of kinin peptides through aminopeptidase activity restoration

    Description Of The Hemipenial Morphology Of Tupinambis Quadrilineatus Manzani And Abe, 1997 (squamata, Teiidae) And New Records From Piauí, Brazil

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    Few data are available on the morphology of the hemipenis of teiid lizards, especially those of the recentlydefined genus Tupinambis, a widely-distributed group of large-bodied lizards. This study provides an illustrated description of the hemipenis of Tupinambis quadrilineatus, which is similar to that of other representatives of the Tupinambinae subfamily. New records of the species from the state of Piauí, in northeastern Brazil, are also presented. © Marcélia Basto da Silva et al.3616172Avila-Pires, T.C.S., (1995) Lizards of Brazilian Amazonia (Reptilia: Squamata), p. 706. , Zoologische VerhandelingenBarreto, L., Arzabe, C., Lima, Y.C.C., Herpetofauna da região de Balsas (2007) Cerrado Norte do Brasil, pp. 221-229. , In: Barreto L (Ed), USEB, PelotasBöhme, W., Zur Genitalmorphologie der Sauria: Funktionelle und stammesgeschichtliche Aspekte (1988) Bonner Zoologische Monographien, 27, pp. 1-176Colli, G.R., Péres Jr., A.K., Cunha, H.J., A new species of Tupinambis (Squamata: Teiidae) from Central Brazil, with an analysis of morphological and genetic variation in the genus (1998) Herpetologica, 54 (4), pp. 477-492Cope, E.D., On the hemipenes of the Sauria (1896) Proceedings of the Academy of Natural Sciences of Philadelphia, 48, pp. 461-467Costa, H.C., São Pedro, V.A., Péres, A.K., Feio, N.R., Reptilia, Squamata, Teiidae, Tupinambis longilineus: Distribution extension (2008) Check List, 4, pp. 267-268Dal Vechio, F., Recoder, R., Rodrigues, M.T., Zaher, H., The herpetofauna of the Estação Ecológica de Uruçuí-Una, state of Piauí, Brazil (2013) Papéis Avulsos de Zoologia, 53 (16), pp. 225-243. , doi: 10.1590/S0031-10492013001600001Dowling, H.G., Duellman, W.E., (1978) Systematic Herpetology: A Synopsis of Families and Higher Categories, p. 118. , HISS Publications, New YorkFerreira, L.V., Pereira, J.L.G., Avila-Pires, T.C.S., Chaves, P.P., Cunha, D.A., Furtado, C.S., Primeira ocorrência de Tupinambis quadrilineatus Manzani, Abe, 1997 (Squamata: Teiidae) no bioma Amazônia (2009) Boletim do Museu Paraense Emílio Goeldi Ciências Naturais, 4 (3), pp. 355-361Fitzgerald, L.A., Cook, J.A., Aquino, A.J., Molecular phylogenetics and conservation of Tupinambis (Sauria: Teiidae) (1999) Copeia, pp. 894-905. , doi: 10.2307/1447965Guimarães, T.C.S., Figueiredo, G.B., Salmito, W.E., Geographic distribution: Tupinambis quadrilineatus (2007) Herpetological Review, 38 (3), pp. 353-354Harvey, M.B., Ugueto, G.N., Gutberlet, R.L., Review of Teiid Morphology with a Revised Taxonomy and Phylogeny of the Teiidae (Lepidosauria: Squamata) (2012) Zootaxa, pp. 1-156. , http://zoobank.org/References/457C2AD0-E5CF-4A41-B6CB-11722700BC5FLangstroth, R.P., Adiciones probables y confirmadas para la saurofauna boliviana (2005) Kempffiana, 1 (1), pp. 101-128Levington, A.E., McDiarmid, R., Moody, S., Nickerson, M., Rosado, J., Sokol, O., Voris, H., Museum acronyms (1980) Second edition, Herpetological Review, 11, pp. 93-102Lima, A.C., Pimenta, F.E., Reptilia, Squamata, Teiidae, Tupinambis longilineus: Distribution extension (2008) Check List, 4, pp. 240-243Manzani, P.R., Abe, A., A new species of Tupinambis Daudin, 1802 (Squamata: Teiidae) from Brazil (1997) Boletim do Museu Nacional, Nova Série, Zoologia, 382, pp. 1-10Manzani, P.R., Abe, A., Sobre dois novos métodos de preparação de hemipênis de serpentes (1988) Memórias do Instituto Butantan, 50 (1), pp. 15-20Manzani, P.R., Abe, A.S., A new species of Tupinambis Daudin, 1803 from southeastern Brazil (Squamata, Teiidae) (2002) Arquivos do Museu Nacional, Rio de Janeiro, 60, pp. 295-302Mesquita, D.O., Colli, G.R., França, F.G.R., Vitt, L.J., Ecology of a Cerrado lizard assemblage in the Jalapão region of Brazil (2006) Copeia 2006, (3), pp. 460-471. , doi: 10.1643/0045-8511(2006)2006[460:EOACLA]2.0.CO;2Moreira, L.A., Fenolio, D.B., Silva, H.L.R., Silva Jr., N.J., A preliminary list of the Herpetofauna from termite mounds of the cerrado in the Upper Tocantins river valley (2009) Papéis Avulsos de Zoologia, 49 (15), pp. 183-189. , http://www.scielo.br/scielo.php?pid=S0031-10492009001500001&script=sci_arttextMyers, C.H., Williams, E.E., McDiarmid, R.W., A new anoline lizard (Phenacosaurus) from the highland of Cerro de la Neblina, Southern Venezuela (1993) American Museum Novitates 3070, pp. 1-15Pesantes, O.S., A method for preparing the hemipenis of preserved snakes (1994) Journal of Herpetology, 28, pp. 93-95. , doi: 10.2307/1564686Recoder, R., Nogueira, C., Composição e diversidade de répteis na região sul do Parque Nacional Grande Sertão Veredas, Brasil Central (2007) Biota Neotropica, 7 (3), pp. 267-278. , doi: 10.1590/S1676-06032007000300029Recoder, R.S., Junior, M.T., Camacho, A., Nunes, P.M.S., Mott, T., Valdujo, P.H., Ghellere, J.M., Rodrigues, M.T., Répteis da Estação Ecológica Serra Geral do Tocantins, Brasil Central (2011) Biota Neotropica, 11 (1), pp. 263-282. , doi: 10.1590/S1676-06032011000100026Savage, J.M., On terminology for the description of the hemipenis of squamate reptiles (1997) Herpetological Journal, 7, pp. 23-25. , doi: 10.1590/S1984-46702011000400005Silva Jr., N.J., Silva, H.L.R., Rodrigues, M.T., Valle, N.C.U., Costa, M.C., Castro, S.P., Linder, E.T., Sites Jr., J.W., A fauna de vertebrados do vale do alto rio Tocantins em áreas de usinas hidrelétricas (2005) Estudos, 32, pp. 57-101Silveira, A.L., Reptilia, Squamata, Teiidae, Tupinambis quadrilineatus: Distribution extension and geographic distribution map (2009) Check List, 5 (3), pp. 442-445Taylor, J.F., Genus Tupinambis, Tegus (2003) Reptilia, 27, pp. 43-49Vitt, L.J., Cadwell, J.P., Colli, G.R., Garda, A.A., Mesquita, D.O., França, F.G.R., Shepard, D.B., Silva, V.N., Uma atualização do guia fotográfico dos répteis e anfíbios da região do Jalapão no Cerrado brasileiro (2005) Special Publications in Herpetology, San Noble Oklahoma Museum of Nature History, 2, pp. 1-24Werneck, F.P., Colli, G.R., The lizard assemblage from seasonally dry tropical forest enclaves in the Cerrado biome, Brazil, and its association with the pleistocenic arc (2006) Journal of Biogeography, 33, pp. 1983-1992. , doi: 10.1111/j.1365-2699.2006.01553.xZaher, H., Prudente, A.L.C., Hemipenis of Siphlophis (Serpentes, Xenodontinae) and Techniques of Hemipenial Preparation in Snakes: A Response to Dowling (2003) Herpetological Review, 34, pp. 302-30

    Analysis of bioactivities and chemical composition of Ziziphus joazeiro Mart. using HPLC–DAD

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    AbstractThe aim of this study was to evaluate the chemical profile and antioxidant, antimicrobial and antiparasitic activities of the hydroalcoholic extract of the leaves of Ziziphus joazeiro Mart. (HELZJ). The antioxidant DPPH and FRAP assays and chemical profile were determined by colorimetric methods and HPLC/DAD. The antiparasitic, antibiotic and antibiotic-modifying activity were evaluated by microdilution assays. The HPLC–DAD assay showed the presence of mostly tannins and flavonoids, such as caffeic acid and quercetin. The levels of polyphenols and flavonoids were 183.136mg/g extract and 7.37mg/g extract, respectively. DPPH and FRAP showed low antioxidant activity for the extract. The antibacterial and antifungal activities were not of clinical relevance, showing MIC>1024μg/mL. However, synergism was observed between HELZJ and the antibiotics amikacin and gentamicin, which resulted in decreased bacterial drug resistance. EHFZJ showed low toxicity in fibroblasts in vitro, while antiparasitic results against Trypnosoma cruzi, Leishmania braziliensis and Leishmania infantum were not clinically relevant. Thus, our results indicate that Z. joazeiro Mart. (HELZJ) could be a source of plant-derived natural products that could lead to the development of promising new antibiotic compounds for infectious diseases

    M-Theory Moduli Space and Cosmology

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    We conduct a systematic search for a viable string/M-theory cosmology, focusing on cosmologies that include an era of slow-roll inflation, after which the moduli are stabilized and the Universe is in a state with an acceptably small cosmological constant. We observe that the duality relations between different cosmological backgrounds of string/M-theory moduli space are greatly simplified, and that this simplification leads to a truncated moduli space within which possible cosmological solutions lie. We review some known challenges to four dimensional models in the "outer", perturbative, region of moduli space, and use duality relations to extend them to models of all of the (compactified) perturbative string theories and 11D supergravity, including brane world models. We conclude that cosmologies restricted to the outer region are not viable, and that the most likely region of moduli space in which to find realistic cosmology is the "central", non-perturbative region, with coupling and compact volume both of order unity, in string units.Comment: 42 pages, 3 figure
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