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Inequality on the frontline: A multi-country study on gender differences in mental health among healthcare workers during the COVID-19 pandemic
- Diana Czepiel, Clare McCormack, Andréa T.C. da Silva, Dominika Seblova, Maria F. Moro, Alexandra Restrepo-Henao, Adriana M. Martínez, Oyeyemi Afolabi, Lubna Alnasser, Rubén Alvarado, Hiroki Asaoka, Olatunde Ayinde, Arin Balalian, Dinarte Ballester, Josleen A.l. Barathie, Armando Basagoitia, Djordje Basic, María S. Burrone, Mauro G. Carta, Sol Durand-Arias, Mehmet Eskin, Eduardo Fernández-Jiménez, Marcela I. F. Frey, Oye Gureje, Anna Isahakyan, Rodrigo Jaldo, Elie G. Karam, Dorra Khattech, Jutta Lindert, Gonzalo Martínez-Alés, Franco Mascayano, Roberto Mediavilla, Javier A. Narvaez Gonzalez, Aimee Nasser-Karam, Daisuke Nishi, Olusegun Olaopa, Uta Ouali, Victor Puac-Polanco, Dorian E. Ramírez, Jorge Ramírez, Eliut Rivera-Segarra, Bart P.F. Rutten, Julian Santaella-Tenorio, Jaime C. Sapag, Jana Šeblová, María T. S. Soto, Maria Tavares-Cavalcanti, Linda Valeri, Marit Sijbrandij, Ezra S. Susser, Hans W. Hoek, Els van der Ven
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- Journal:
- Cambridge Prisms: Global Mental Health / Volume 11 / 2024
- Published online by Cambridge University Press:
- 04 March 2024, e34
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Healthcare workers (HCWs) were at increased risk for mental health problems during the COVID-19 pandemic, with prior data suggesting women may be particularly vulnerable. Our global mental health study aimed to examine factors associated with gender differences in psychological distress and depressive symptoms among HCWs during COVID-19. Across 22 countries in South America, Europe, Asia and Africa, 32,410 HCWs participated in the COVID-19 HEalth caRe wOrkErS (HEROES) study between March 2020 and February 2021. They completed the General Health Questionnaire-12, the Patient Health Questionnaire-9 and questions about pandemic-relevant exposures. Consistently across countries, women reported elevated mental health problems compared to men. Women also reported increased COVID-19-relevant stressors, including insufficient personal protective equipment and less support from colleagues, while men reported increased contact with COVID-19 patients. At the country level, HCWs in countries with higher gender inequality reported less mental health problems. Higher COVID-19 mortality rates were associated with increased psychological distress merely among women. Our findings suggest that among HCWs, women may have been disproportionately exposed to COVID-19-relevant stressors at the individual and country level. This highlights the importance of considering gender in emergency response efforts to safeguard women’s well-being and ensure healthcare system preparedness during future public health crises.
Could combination chemotherapy be more effective than monotherapy in the treatment of visceral leishmaniasis? A systematic review of preclinical evidence
- Daniel S. S. Bastos, Adriana C. Silva, Rômulo D. Novaes, Ana Claudia F. Souza, Eliziária C. Santos, Reggiani V. Gonçalves, Eduardo A. Marques-Da-Silva
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- Journal:
- Parasitology / Volume 149 / Issue 6 / May 2022
- Published online by Cambridge University Press:
- 09 February 2022, pp. 751-764
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From a systematic review framework, we assessed the preclinical evidence on the effectiveness of drug combinations for visceral leishmaniasis (VL) treatment. Research protocol was based on the PRISMA guideline. Research records were identified from Medline, Scopus and Web of Science. Animal models, infection and treatment protocols, parasitological and immunological outcomes were analysed. The SYRCLE's (SYstematic Review Center for Laboratory Animal Experimentation) toll was used to evaluate the risk of bias in all studies reviewed. Fourteen papers using mice, hamster and dogs were identified. Leishmania donovani was frequently used to induce VL, which was treated with 23 drugs in 40 different combinations. Most combinations allowed to reduce the effective dose, cost and time of treatment, in addition to improving the parasitological control of Leishmania spp. The benefits achieved from drug combinations were associated with an increased drug's half-life, direct parasitic toxicity and improved immune defences in infected hosts. Selection, performance and detection bias were the main limitations identified. Current evidence indicates that combination chemotherapy, especially those based on classical drugs (miltefosine, amphotericin B antimony-based compounds) and new drugs (CAL-101, PAM3Cys, tufisin and DB766), develops additive or synergistic interactions, which trigger trypanocidal and immunomodulatory effects associated with reduced parasite load, organ damage and better cure rates in VL.
Sumatran fleabane (Conyza sumatrensis) resistant to PSI-inhibiting herbicides and physiological responses to paraquat
- Jéssica F. L. Leal, Amanda dos S. Souza, Junior Borella, André Lucas S. Araujo, Ana Claudia Langaro, Ana Carolina Chapeta, Eduardo S. Amorim, Gabriela S. Silva, Sarah Morran, Luiz Henrique S. Zobiole, Todd A. Gaines, Camila F. de Pinho
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- Journal:
- Weed Science / Volume 70 / Issue 1 / January 2022
- Published online by Cambridge University Press:
- 02 November 2021, pp. 46-54
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Herbicide-resistant weed management is one of the greatest agricultural challenges in crop production. Thus, the quick identification of herbicide-resistant weeds is extremely important for management. This study aimed to evaluate resistance to PSI-inhibiting herbicides (diquat) and physiological response to paraquat application in Sumatran fleabane [Conyza sumatrensis (Retz.) E. Walker; syn.: Erigeron sumatrensis Retz.]. The research was conducted with two C. sumatrensis biotypes, one susceptible and the other with multiple resistance to herbicides from five different modes of action (glyphosate, paraquat, diuron, saflufenacil, and 2,4-D). A dose–response assay was carried out to evaluate herbicide resistance to diquat in the paraquat-resistant C. sumatrensis biotype. The enzymatic activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), hydrogen peroxide (H2O2) content, and chlorophyll a (Chl a) fluorescence were measured in both biotypes after paraquat (400 g ai ha−1) application. The dose–response assay confirmed resistance of C. sumatrensis to diquat with resistance factor levels of 26-fold and 6-fold for LD50 and GR50 values, respectively, compared with the susceptible biotype. Accumulation of H2O2 occurred more rapidly in the paraquat-susceptible biotype than in the resistant one. Paraquat treatment caused an increase in SOD and APX activity in the susceptible biotype, but antioxidant enzyme activities were unaffected by paraquat in the resistant one at 5 h after application (HAA). Chl a fluorescence increased across the first 4 HAA in both resistant and susceptible biotypes. However, at 24 HAA, the resistant biotype showed a decline in fluorescence close to untreated plants, while the susceptible biotype died, confirming resistance to diquat in the paraquat-resistant C. sumatrensis biotype. The paraquat-resistant biotype does not induce antioxidative enzymes, as a possible mechanism of resistance to paraquat, but shows rapid recovery of photosynthesis and continuous growth when subjected to paraquat, while the paraquat-susceptible biotype does not survive.
Diagnostic application of sensitive and specific phage-exposed epitopes for visceral leishmaniasis and human immunodeficiency virus coinfection
- Fernanda F. Ramos, Grasiele S. V. Tavares, Fernanda Ludolf, Amanda S. Machado, Thaís T. O. Santos, Isabela A. P. Gonçalves, Ana C. S. Dias, Patrícia T. Alves, Vanessa G. Fraga, Raquel S. Bandeira, João A. Oliveira-da-Silva, Thiago A. R. Reis, Daniela P. Lage, Vívian T. Martins, Camila S. Freitas, Ana T. Chaves, Nathalia S. Guimarães, Miguel A. Chávez-Fumagalli, Unaí Tupinambás, Manoel O. C. Rocha, Gláucia F. Cota, Ricardo T. Fujiwara, Lílian L. Bueno, Luiz Ricardo Goulart, Eduardo A. F. Coelho
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- Journal:
- Parasitology / Volume 148 / Issue 13 / November 2021
- Published online by Cambridge University Press:
- 19 August 2021, pp. 1706-1714
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The diagnosis of visceral leishmaniasis (VL) has improved with the search of novel antigens; however, their performance is limited when samples from VL/human immunodeficiency virus (HIV)-coinfected patients are tested. In this context, studies conducted to identify more suitable antigens to detect both VL and VL/HIC coinfection cases should be performed. In the current study, phage display was performed using serum samples from healthy subjects and VL, HIV-infected and VL/HIV-coinfected patients; aiming to identify novel phage-exposed epitopes to be evaluated with this diagnostic purpose. Nine non-repetitive and valid sequences were identified, synthetized and tested as peptides in enzyme-linked immunosorbent assay experiments. Results showed that three (Pep2, Pep3 and Pep4) peptides showed excellent performance to diagnose VL and VL/HIV coinfection, with 100% sensitivity and specificity values. The other peptides showed sensitivity varying from 50.9 to 80.0%, as well as specificity ranging from 60.0 to 95.6%. Pep2, Pep3 and Pep4 also showed a potential prognostic effect, since specific serological reactivity was significantly decreased after patient treatment. Bioinformatics assays indicated that Leishmania trypanothione reductase protein was predicted to contain these three conformational epitopes. In conclusion, data suggest that Pep2, Pep3 and Pep4 could be tested for the diagnosis of VL and VL/HIV coinfection.
Homogenised and pasteurised human milk: lipid profile and effect as a supplement in the enteral diet of Wistar rats
- Kely de Paula Correa, Monique E. T. Silva, Otávio S. Ribeiro, Sérgio L. P. Matta, Maria do Carmo G. Peluzio, Eduardo B. Oliveira, Jane S. dos R. Coimbra
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- Journal:
- British Journal of Nutrition / Volume 127 / Issue 5 / 14 March 2022
- Published online by Cambridge University Press:
- 27 April 2021, pp. 711-721
- Print publication:
- 14 March 2022
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The retention of human milk (HM) fat in nasogastric probes of infusion pumps can be observed during the feed of infants unable to suck at the mother’s breast. The lack of homogenisation of HM could contribute to the fat holding. Therefore, the present study evaluated (i) the influence of homogenisation on milk fat retaining in infant feeding probes and (ii) the in vivo effect of the homogenisation on lipid absorption by Wistar rats. The animals were fed with HM treated following two processing conditions, that is, pasteurised and homogenised–pasteurised. The animals were randomly subdivided into four experimental groups: water-fed (control), pasteurised milk, homogenised–pasteurised milk and pasteurised–skimmed milk. The results of food consumption, mass body gain, corporate metrics and plasma blood levels of total cholesterol did not show any difference (P < 0·05) among the three types of HM used in the experiments. The liver, intestine and intra-abdominal adipose tissue of the four groups of animals presented normal and healthy histology. The composition of fatty acids in the brain tissue of animals fed with homogenised HM increased when compared with the groups fed with non-homogenised HM. These values were 11·08 % higher for arachidonic acids, 6·59 % for DAH and 47·92 % for nervous acids. The ingestion of homogenised HM promoted higher absorption of milk nutrients. Therefore, the addition of the homogenisation stage in HM processing could be an alternative to reduce fat retention in probes and to improve the lipids’ absorption in the body.
An immunoproteomics approach to identify Leishmania infantum proteins to be applied for the diagnosis of visceral leishmaniasis and human immunodeficiency virus co-infection
- Amanda S. Machado, Fernanda F. Ramos, João A. Oliveira-da-Silva, Thaís T. O. Santos, Grasiele S. V. Tavares, Lourena E. Costa, Daniela P. Lage, André Teixeira-Ferreira, Jonas Perales, Ana Paula Fernandes, Ricardo L. F. Moreira, Mariana C. Duarte, Unaí Tupinambás, Rachel B. Caligiorne, Gláucia F. Cota, Eduardo A. F. Coelho, Fernanda Ludolf
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- Journal:
- Parasitology / Volume 147 / Issue 9 / August 2020
- Published online by Cambridge University Press:
- 20 April 2020, pp. 932-939
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The co-infection between visceral leishmaniasis (VL) and human immunodeficiency virus (HIV) has increased in several countries in the world. The current serological tests are not suitable since they present low sensitivity to detect the most of VL/HIV cases, and a more precise diagnosis should be performed. In this context, in the present study, an immunoproteomics approach was performed using Leishmania infantum antigenic extracts and VL, HIV and VL/HIV patients sera, besides healthy subjects samples; aiming to identify antigenic markers for these clinical conditions. Results showed that 43 spots were recognized by antibodies in VL and VL/HIV sera, and 26 proteins were identified by mass spectrometry. Between them, β-tubulin was expressed, purified and tested in ELISA experiments as a proof of concept for validation of our immunoproteomics findings and results showed high sensitivity and specificity values to detect VL and VL/HIV patients. In conclusion, the identified proteins in the present work could be considered as candidates for future studies aiming to improvement of the diagnosis of VL and VL/HIV co-infection.
Solvent effect on the structure and photocatalytic behavior of TiO2-RGO nanocomposites
- Bruno S. Gonçalves, Lucas M.C. Silva, Tarcizo C.C. de Souza, Vinícius G. de Castro, Glaura G. Silva, Bruno C. Silva, Klaus Krambrock, Renata B. Soares, Vanessa F.C. Lins, Manuel Houmard, Eduardo H.M. Nunes
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- Journal:
- Journal of Materials Research / Volume 34 / Issue 23 / 16 December 2019
- Published online by Cambridge University Press:
- 22 November 2019, pp. 3918-3930
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- 16 December 2019
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There is no agreement regarding which solvent is more suitable to obtain sol–gel–derived titania (TiO2) samples with an enhanced photocatalytic behavior. Furthermore, the solvent effect on the preparation of TiO2-RGO (reduced graphene oxide) nanocomposites has not been published yet and could be an attractive experimental strategy to modulate structure and properties. On the basis of these observations, TiO2-RGO nanocomposites were fabricated in this study. It was evaluated for the influence of using either isopropyl (IsoprOH) or ethyl (EtOH) alcohol on the textural and photocatalytic properties of the prepared materials. The use of IsoprOH led to samples with smaller crystallite size, narrower apparent band gap, smaller isoelectric point, larger adsorption capacity, and higher photocatalytic activity. In addition, the incorporation of RGO into TiO2 greatly improved the adsorption capacity and photocatalytic activity of the latter. However, the optimal loading of RGO to prepare composites with enhanced photocatalytic activities was 1 wt%. This finding can be related to the stacking of RGO sheets when concentrations above 1 wt% are used, which could prevent UV light to reach the TiO2 particles and also decrease the photocatalytic capacity of the composites. Moreover, materials with RGO concentration above 1 wt% could exhibit a highly negatively charged surface, which may decrease the separation of the generated electron–hole pairs and lead to faster recombination rates of charge carriers.
High-through identification of T cell-specific phage-exposed mimotopes using PBMCs from tegumentary leishmaniasis patients and their use as vaccine candidates against Leishmania amazonensis infection
- Gerusa B. Carvalho, Lourena E. Costa, Daniela P. Lage, Fernanda F. Ramos, Thaís T. O. Santos, Patrícia A. F. Ribeiro, Daniel S. Dias, Beatriz C. S. Salles, Mariana P. Lima, Lívia M. Carvalho, Ana C. S. Dias, Patrícia T. Alves, Michelle L. Franklin, Renata A. M. Silva, Mariana C. Duarte, Daniel Menezes-Souza, Bruno M. Roatt, Miguel A. Chávez-Fumagalli, Luiz Ricardo Goulart, Antonio L. Teixeira, Eduardo A. F. Coelho
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- Parasitology / Volume 146 / Issue 3 / March 2019
- Published online by Cambridge University Press:
- 10 September 2018, pp. 322-332
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In the current study, phage-exposed mimotopes as targets against tegumentary leishmaniasis (TL) were selected by means of bio-panning cycles employing sera of TL patients and healthy subjects, besides the immune stimulation of peripheral blood mononuclear cells (PBMCs) collected from untreated and treated TL patients and healthy subjects. The clones were evaluated regarding their specific interferon-γ (IFN-γ) and interleukin-4 (IL-4) production in the in vitro cultures, and selectivity and specificity values were calculated, and those presenting the best results were selected for the in vivo experiments. Two clones, namely A4 and A8, were identified and used in immunization protocols from BALB/c mice to protect against Leishmania amazonensis infection. Results showed a polarized Th1 response generated after vaccination, being based on significantly higher levels of IFN-γ, IL-2, IL-12, tumour necrosis factor-α (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF); which were associated with lower production of specific IL-4, IL-10 and immunoglobulin G1 (IgG1) antibodies. Vaccinated mice presented significant reductions in the parasite load in the infected tissue and distinct organs, when compared with controls. In conclusion, we presented a strategy to identify new mimotopes able to induce Th1 response in PBMCs from TL patients and healthy subjects, and that were successfully used to protect against L. amazonensis infection.
Keto analogues and amino acid supplementation and its effects on ammonaemia during extenuating endurance exercise in ketogenic diet-fed rats
- Rogério T. Ferreira, Sandra C. Gonçalves, Maria L. Pedrosa, Marcelo E. Silva, Adriana Bassini, Wagner S. Coelho, Aníbal M. de Magalhães-Neto, Eduardo S. Prado, L. C. Cameron
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- Journal:
- British Journal of Nutrition / Volume 120 / Issue 7 / 14 October 2018
- Published online by Cambridge University Press:
- 06 August 2018, pp. 732-739
- Print publication:
- 14 October 2018
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Keto analogues and amino acids (KAAA) supplementation can reduce blood ammonia concentrations in athletes undergoing high-intensity exercise under both ketogenic and thermoneutral conditions. This study evaluated the acute effects of KAAA supplementation on ammonia metabolism during extenuating endurance exercise in rats fed a ketogenic diet. In all, eighty male Fischer rats at 90 d of age were divided into eight groups, and some were trained using a swimming endurance protocol. A ketogenic diet supplemented with keto analogues was administered for 10 d. Administration of the ketogenic diet ended 3 d before the exhaustion test (extenuating endurance exercise). A ketogenic diet plus KAAA supplementation and extenuating endurance exercise (trained ketogenic diet supplemented with KAAA (TKKa)) increased blood ammonia concentrations by approximately 50 % compared with the control diet (trained control diet supplemented with KAAA (TCKa)) and similar training (effect size=1·33; statistical power=0·50). The KAAA supplementation reduced blood urea concentrations by 4 and 18 % in the control and ketogenic diet groups, respectively, compared with the groups fed the same diets without supplementation. The trained groups had 60 % lower blood urate concentrations after TCKa treatment than after TKKa treatment. Our results suggest that KAAA supplementation can reduce blood ammonia concentrations after extenuating endurance exercise in rats fed a balanced diet but not in rats fed a ketogenic diet.
The helminth community of a population of Rattus norvegicus from an urban Brazilian slum and the threat of zoonotic diseases
- Ticiana Carvalho-Pereira, Fábio N. Souza, Luana R. N. Santos, Ruth Walker, Arsinoê C. Pertile, Daiana S. de Oliveira, Gabriel G. Pedra, Amanda Minter, Maria Gorete Rodrigues, Thiago C. Bahiense, Mitermayer G. Reis, Peter J. Diggle, Albert I. Ko, James E. Childs, Eduardo M. da Silva, Mike Begon, Federico Costa
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- Parasitology / Volume 145 / Issue 6 / May 2018
- Published online by Cambridge University Press:
- 08 November 2017, pp. 797-806
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Urban slums provide suitable conditions for infestation by rats, which harbour and shed a wide diversity of zoonotic pathogens including helminths. We aimed to identify risk factors associated with the probability and intensity of infection of helminths of the digestive tract in an urban slum population of Rattus norvegicus. Among 299 rats, eleven species/groups of helminths were identified, of which Strongyloides sp., Nippostrongylus brasiliensis and, the human pathogen, Angiostrongylus cantonensis were the most frequent (97, 41 and 39%, respectively). Sex interactions highlighted behavioural differences between males and females, as eg males were more likely to be infected with N. brasiliensis where rat signs were present, and males presented more intense infections of Strongyloides sp. Moreover, rats in poor body condition had higher intensities of N. brasiliensis. We describe a high global richness of parasites in R. norvegicus, including five species known to cause disease in humans. Among these, A. cantonensis was found in high prevalence and it was ubiquitous in the study area – knowledge which is of public health importance. A variety of environmental, demographic and body condition variables were associated with helminth species infection of rats, suggesting a comparable variety of risk factors for humans.
Antigenicity, immunogenicity and protective efficacy of a conserved Leishmania hypothetical protein against visceral leishmaniasis
- Daniel S. Dias, Vívian T. Martins, Patrícia A. F. Ribeiro, Fernanda F. Ramos, Daniela P. Lage, Grasiele S. V. Tavares, Débora V. C. Mendonça, Miguel A. Chávez-Fumagalli, Jamil S. Oliveira, Eduardo S. Silva, Dawidson A. Gomes, Michele A. Rodrigues, Mariana C. Duarte, Alexsandro S. Galdino, Daniel Menezes-Souza, Eduardo A. F. Coelho
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- Parasitology / Volume 145 / Issue 6 / May 2018
- Published online by Cambridge University Press:
- 08 November 2017, pp. 740-751
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In this study, a Leishmania hypothetical protein, LiHyS, was evaluated regarding its antigenicity, immunogenicity and protective efficacy against visceral leishmaniasis (VL). Regarding antigenicity, immunoblottings and an enzyme-linked immunosorbent assay using human and canine sera showed high sensitivity and specificity values for the recombinant protein (rLiHyS) in the diagnosis of VL. When evaluating the immunogenicity of LiHyS, which is possibly located in the parasite's flagellar pocket, proliferative assays using peripheral blood mononuclear cells from healthy subjects or VL patients showed a high proliferative index in both individuals, when compared to the results obtained using rA2 or unstimulated cultures. Later, rLiHyS/saponin was inoculated in BALB/c mice, which were then challenged with Leishmania infantum promastigotes. The vaccine induced an interferon-γ, interleukin (IL)-12 and granulocyte-macrophage colony-stimulating factor production, which was maintained after infection and which was associated with high nitrite and IgG2a antibody levels, as well as low IL-4 and IL-10 production. Significant reductions in the parasite load in liver, spleen, bone marrow and draining lymph nodes were found in these animals. In this context, the present study shows that the rLiHyS has the capacity to be evaluated as a diagnostic marker or vaccine candidate against VL.
Rheological properties of HDPE/chitosan composites modified with PE-g-MA
- Poliana S. Lima, Rebecca S.F. Brito, Bárbara F.F. Santos, Albaniza A. Tavares, Pankaj Agrawal, Daniela L.A.C.S. Andrade, Renate M.R. Wellen, Eduardo L. Canedo, Suédina M.L. Silva
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- Journal:
- Journal of Materials Research / Volume 32 / Issue 4 / 28 February 2017
- Published online by Cambridge University Press:
- 30 January 2017, pp. 775-787
- Print publication:
- 28 February 2017
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The rheological behavior of composites made with high-density polyethylene (HDPE) and chitosan was studied. Composites were prepared by melt processing in a laboratory internal mixer. Maleic anhydride grafted HDPE (PE-g-MA) was used as compatibilizer to enhance the dispersion of chitosan in the HDPE matrix. Different percentages of chitosan and compatibilizer (up to a maximum of 25 phr) were added into HDPE to prepare composites. Characterization of the composites with parallel plate rheometer and laboratory internal mixer revealed that the presence of chitosan increases the complex viscosity, loss modulus, storage modulus and the torque (i.e., melt viscosity), and the combination chitosan/compatibilizer has a similar, if slighter, effect. At higher filler levels it is clear that the PE-g-MA affected the microstructure of the compounds, possibly increasing matrix–filler interactions and acting as an effective compatibilizer.
A phylogenetic framework for reassessing generic concepts and species delimitation in the lichenized family Trypetheliaceae (Ascomycota: Dothideomycetes)
- Robert LÜCKING, Matthew P. NELSEN, André APTROOT, Roselvira BARILLAS DE KLEE, Paulina A. BAWINGAN, Michel N. BENATTI, Nguyen Quoc BINH, Frank BUNGARTZ, Marcela E. S. CÁCERES, Luciana da Silva CANÊZ, José-Luis CHAVES, Damien ERTZ, Rhina Esmeralda ESQUIVEL, Lidia Itati FERRARO, Alfredo GRIJALVA, Cécile GUEIDAN, Jesús E. HERNÁNDEZ M., Allison KNIGHT, H. Thorsten LUMBSCH, Marcelo P. MARCELLI, Joel A. MERCADO-DÍAZ, Bibiana MONCADA, Eduardo A. MORALES, Khwanruan NAKSUWANKUL, Thelma OROZCO, Sittiporn PARNMEN, Eimy RIVAS PLATA, Noris SALAZAR-ALLEN, Adriano A. SPIELMANN, Nohemy VENTURA
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- Journal:
- The Lichenologist / Volume 48 / Issue 6 / November 2016
- Published online by Cambridge University Press:
- 07 December 2016, pp. 739-762
- Print publication:
- November 2016
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We provide an expanded and updated, 2-locus phylogeny (mtSSU, nuLSU) of the lichenized fungal family Trypetheliaceae, with a total of 196 ingroup OTUs, in order to further refine generic delimitations and species concepts in this family. As a result, the following 15 clades are recognized as separate genera, including five newly established genera: Aptrootia, Architrypethelium, Astrothelium (including the bulk of corticate species with astrothelioid ascospores; synonyms: Campylothelium, Cryptothelium, Laurera), Bathelium s. str. (excluding B. degenerans and relatives which fall into Astrothelium), the reinstated Bogoriella (for tropical, lichenized species previously placed in Mycomicrothelia), Constrictolumina gen. nov. (for tropical, lichenized species of Arthopyrenia), Dictyomeridium gen. nov. (for a subgroup of species with muriform ascospores previously placed in Polymeridium), Julella (provisionally, as the type species remains unsequenced), Marcelaria (Laurera purpurina complex), Nigrovothelium gen. nov. (for the Trypethelium tropicum group), Novomicrothelia gen. nov. (for an additional species previously placed in Mycomicrothelia), Polymeridium s. str., Pseudopyrenula, Trypethelium s. str. (T. eluteriae group), and Viridothelium gen. nov. (for the Trypethelium virens group). All recognized genera are phenotypically characterized and a discussion on the evolution of phenotypic features in the family is given. Based on the obtained phylogeny, species delimitations are revised and the importance of characters such as thallus morphology, hymenial inspersion, and secondary chemistry for taxonomic purposes is discussed, resulting in a refined species concept.
Contributors
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- By Krista Adamek, Ana Luisa K. Albernaz, J. Marcio Ayres†, Andrew J. Baker, Karen L. Bales, Adrian A. Barnett, Christopher Barton, John M. Bates, Jennie Becker, Bruna M. Bezerra, Júlio César Bicca-Marques, Richard Bodmer, Jean P. Boubli, Mark Bowler, Sarah A. Boyle, Christini Barbosa Caselli, Janice Chism, Elena P. Cunningham, José Maria C. da Silva, Lesa C. Davies, Nayara de Alcântara Cardoso, Manuella A. de Souza, Stella de la Torre, Ana Gabriela de Luna, Thomas R. Defler, Anthony Di Fiore, Eduardo Fernandez-Duque, Stephen F. Ferrari, Wilsea M.B. Figueiredo-Ready, Tracy Frampton, Paul A. Garber, Brian W. Grafton, L. Tremaine Gregory, Maria L. Harada, Amy Harrison-Levine, Walter C. Hartwig, Stefanie Heiduck, Eckhard W. Heymann, André Hirsch, Leandro Jerusalinsky, Gareth Jones, Richard F. Kay, Martin M. Kowalewski, Shawn M. Lehman, Laura Marsh, Jesús Martinez, William A. Mason, Hope Matthews, Wynlyn McBride, Shona McCann-Wood, W. Scott McGraw, D. Jeffrey Meldrum, Sally P. Mendoza, Nohelia Mercado, Russell A. Mittermeier, Mirjam N. Nadjafzadeh, Marilyn A. Norconk, Robert Gary Norman, Marcela Oliveira, Marcelo M. Oliveira, Maria Juliana Ospina Rodríguez, Erwin Palacios, Suzanne Palminteri, Liliam P. Pinto, Marcio Port-Carvalho, Leila Porter, Carlos Portillo-Quintero, George Powell, Ghillean T. Prance, Rodrigo C. Printes, Pablo Puertas, P. Kirsten Pullen, Helder L. Queiroz, Luis Reginaldo R. Rodrigues, Adriana Rodríguez, Alfred L. Rosenberger, Anthony B. Rylands, Ricardo R. Santos, Horacio Schneider, Eleonore Z.F. Setz, Suleima S.B. Silva, José S. Silva Júnior, Andrew T. Smith, Marcelo C. Sousa, Antonio S. Souto, Wilson R. Spironello, Masanaru Takai, Marcelo F. Tejedor, Cynthia L. Thompson, Diego G. Tirira, Raul Tupayachi, Bernardo Urbani, Liza M. Veiga, Marianela Velilla, João Valsecchi, Jean-Christophe Vié, Tatiana M. Vieira, Suzanne E. Walker-Pacheco, Rob Wallace, Patricia C. Wright, Charles E. Zartman
- Edited by Liza M. Veiga, Universidade Federal do Pará, Brazil, Adrian A. Barnett, Roehampton University, London, Stephen F. Ferrari, Universidade Federal de Sergipe, Brazil, Marilyn A. Norconk, Kent State University, Ohio
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- Book:
- Evolutionary Biology and Conservation of Titis, Sakis and Uacaris
- Published online:
- 05 April 2013
- Print publication:
- 11 April 2013, pp xii-xv
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Ultraviolet sensors using a luminescent europium (III) complex on acrylonitrile butadiene styrene polymer
- Érica A. de Souza, Caroline B. Azevedo, Lucas A. Rocha, Emerson H. de Faria, Paulo S. Calefi, Katia J. Ciuffi, Eduardo J. Nassar, Jorge V.L. Silva, Marcelo Oliveira, Izaque I. Maia
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- Journal:
- Journal of Materials Research / Volume 27 / Issue 16 / 28 August 2012
- Published online by Cambridge University Press:
- 14 May 2012, pp. 2088-2095
- Print publication:
- 28 August 2012
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In this article, the sol-gel methodology was used for coating an acrylonitrile butadiene styrene (ABS) polymer prepared by the rapid prototyping technology with a colloid containing the europium III dipicolinic complex, which presents high emission when excited in the ultraviolet region. Either acid or base was used for treatment of the ABS polymer, with a view to activating its surface. The thermal analysis evidenced a residual mass after 600 °C, which indicated that the coating adhered to the substrate. X-ray diffraction analysis showed that the structure of the ABS polymer was not affected by the sol-gel treatment. The large band centered at 287 nm, ascribed to ligand-metal charge transfer, can be used to excite the europium III dipicolinic complex in the ultraviolet C and ultraviolet B regions. The emission appears in the characteristic red region of the electromagnetic spectrum. These results indicate that the obtained material is a candidate for use as ultraviolet sensor.
The role of a lifetime history of oppositional defiant and conduct disorders in adults with ADHD: implications for clinical practice
- Eduardo S. Vitola, Carlos A. I. Salgado, Katiane L. Silva, Rafael G. Karam, Marcelo M. Victor, Nina R. Mota, Verônica Contini, Felipe A. Picon, Paula O. Guimarães-da-Silva, Rafael S. Giordani, Luis A. Rohde, Paulo Belmonte-de-Abreu, Claiton H. D. Bau, Eugenio H. Grevet
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- CNS Spectrums / Volume 17 / Issue 2 / June 2012
- Published online by Cambridge University Press:
- 04 May 2012, pp. 94-99
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Introduction
Attention-deficit/hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD) are frequently co-occurring disorders in children and adolescents. However, their clinical status among adults is still under discussion. This study analyzes how the current clinical presentation of adult ADHD might be influenced by a lifetime history of CD and ODD.
MethodsWe compared three groups of patients: ADHD without history of CD/ODD (n = 178), ADHD + history of ODD (n = 184), and ADHD + history of CD (n = 96).
ResultsA history of CD (and to a lower extent ODD) is associated with a more severe and externalizing profile.
ConclusionPast CD and ODD entail a significant negative mental health impact on persistent ADHD, reinforcing the importance of actively assessing the developmental history of adult ADHD patients.
Temporal trends in mortality and effects of by-catch on common bottlenose dolphins, Tursiops truncatus, in southern Brazil
- Pedro F. Fruet, Paul G. Kinas, Kleber G. da Silva, Juliana C. Di Tullio, Daniele S. Monteiro, Luciano Dalla Rosa, Sérgio C. Estima, Eduardo R. Secchi
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- Journal:
- Journal of the Marine Biological Association of the United Kingdom / Volume 92 / Issue 8 / December 2012
- Published online by Cambridge University Press:
- 09 December 2010, pp. 1865-1876
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The mortality of the bottlenose dolphin, Tursiops truncatus, on the southern portion of Rio Grande do Sul State coast was investigated based on 914 beach surveys conducted between 1969 and 2006. A total of 188 stranded bottlenose dolphins were recorded during this period, indicating a 1.8M:1F sex-ratio of those animals sexed (N = 79). Mortality was low in calves, high in juveniles and sub-adults and slightly lower than in adults. The overall mortality was clearly seasonal overlapping with higher fishing efforts in the Patos Lagoon Estuary and adjacent coastal areas, where most individuals washed ashore. Analysis of a continuous 14-year long subset (1993–2006) of the data indicated relatively low levels of mortality between 1995 and 2000 and a marked increase between 2002 and 2005 followed by an apparent drop in 2006. By-catch was responsible for at least 43% of the recorded mortality between 2002 and 2006. Juvenile males were more susceptible to incidental catches. Among females, by-catch of adults represented 75%. Results of a potential biological removal analysis suggest that current levels of fishing-related mortality are unsustainable for the small resident population of bottlenose dolphins that inhabits the Patos Lagoon Estuary, and that this population may be declining.
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Contents
- Paulo S. R. Diniz, Universidade Federal do Rio de Janeiro, Eduardo A. B. da Silva, Universidade Federal do Rio de Janeiro, Sergio L. Netto, Universidade Federal do Rio de Janeiro
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- Digital Signal Processing
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- 05 June 2012
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- 02 September 2010, pp vii-xv
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6 - IIR filter approximations
- Paulo S. R. Diniz, Universidade Federal do Rio de Janeiro, Eduardo A. B. da Silva, Universidade Federal do Rio de Janeiro, Sergio L. Netto, Universidade Federal do Rio de Janeiro
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- Digital Signal Processing
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- 05 June 2012
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- 02 September 2010, pp 349-408
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Summary
Introduction
This chapter deals with the design methods in which a desired frequency response is approximated by a transfer function consisting of a ratio of polynomials. In general, this type of transfer function yields an impulse response of infinite duration. Therefore, the systems approximated in this chapter are commonly referred to as IIR filters.
In general, IIR filters are able to approximate a prescribed frequency response with fewer multiplications than FIR filters. For that matter, IIR filters can be more suitable for some practical applications, especially those involving real-time signal processing.
In Section 6.2 we study the classical methods of analog filter approximation, namely the Butterworth, Chebyshev, and elliptic approximations. These methods are the most widely used for approximations meeting prescribed magnitude specifications. They originated in the continuous-time domain and their use in the discrete-time domain requires an appropriate transformation.
We then address, in Section 6.3, two approaches that transform a continuous-time transfer function into a discrete-time transfer function, namely the impulse-invariance and bilinear transformation methods.
Section 6.4 deals with frequency transformation methods in the discrete-time domain. These methods allow the mapping of a given filter type to another; for example, the transformation of a given lowpass filter into a desired bandpass filter.
In applications where magnitude and phase specifications are imposed, we can approximate the desired magnitude specifications by one of the classical transfer functions and design a phase equalizer to meet the phase specifications.