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This study explores a method that has the potential to be cost effective in inhibiting biofilm formation on metallic prostheses, thereby preventing rejection or the requirement for replacement. A cost-effective metal alloy used in biomedical implants was chosen as the substrate, and ibuprofen (Ibu), a well-known anti-inflammatory drug, was selected for drug release tests for its widespread availability and accessibility. Multilayer coatings consisting of cellulose acetate (CA), polycaprolactone (PCL), and chitosan (CHI), with or without ibuprofen (Ibu) content, were applied onto medical-grade stainless steel (SS-316 type) through electrospinning, electrospray, or blow spinning. The adhesion of the CA, PCL, and layered CA/PCL membranes, with thicknesses ranging from 20 to 100 µm, to SS substrates varied between 0.15 N and 0.22 N without CHI, which increased to 0.21 and 0.74 N, respectively, when a CHI interlayer was introduced by electrospraying between the SS and the coatings. Although drug release in a simulated body fluid (SBF) medium is predominantly governed by diffusion-driven mechanisms in all single- and multilayer coatings, a delayed release was noted in CA coatings containing Ibu when overlaid with a PCL coating produced by blow spinning. This suggests avenues for further investigations into combinations of multilayer coatings, both with and without drug-imbued layers.
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Additive Manufacturing (AM) demonstrates significant potential with rapid growth and widespread industrial adoption. To support the integration and innovation of AM technologies, the development of guidance tools and support methods are crucial, and a technological roadmap can assist in this effort. Despite its widespread use in production processes, the need for further research on the potential impact of AM remains significant. The full impact of AM is still uncertain and lacks consensus, highlighting the need for increased knowledge and investment from the scientific community and organizations. While the benefits of AM are recognized, the challenges of its adoption are not entirely known. AM will bring changes in the way organizations create, distribute, and derive value. Thus, in this article, a roadmap for AM is proposed and presented as a tool to map technological knowledge on the implementation and evolution of AM and serve as a strategic guide for organizations. The methodology for its elaboration involves three phases: planning and preparation, roadmap development, and review and update. Through a literature review, database and project consultation, and questionnaires to Portuguese companies that use AM in their production process it was possible to characterize the AM technology and through the visual format, based on a time horizon, summarize in a common framework all the information about the current and future state of AM in Portugal. The results of this study show that research and development initiatives are essential to promote the evolution of knowledge of the AM technology. Throughout this study and with the development of the roadmap it is anticipated that in the near future the AM will be widely used for prototyping and manufacturing of components and may be used for direct production in the short to medium term. It was also found that the main obstacles to the implementation of AM are the economic/productivity factors and the shortage of professionals with knowledge and skills in the area.
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The increasing demand for flexible electronic devices has risen due to the high interest in electronic textiles (e-textiles). Consequently, the urge to power e-textiles has sparked enormous interest in flexible energy storage devices. One-dimensional (1D) configuration supercapacitors are the most promising technology for textile applications, but often their production involves complex synthesis techniques and expensive materials. This work unveils the use of the novel electrospray deposition (ESD) technique for the deposition of poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS). This deposition methodology on conductive carbon yarns creates flexible electrodes with a high surface area. The deposition conditions of PEDOT:PSS were optimized, and their influence on the electrochemical performance of a 1D symmetric supercapacitor with a cellulose-based gel as an electrolyte and a separator was evaluated. The tests herein reported show that these capacitors exhibited a high specific capacitance of 72 mF g-1, an excellent cyclability of more than 85% capacitance retention after 1500 cycles, and an outstanding capability of bending.
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Pores, grains, or textures can collectively cause microstructural inhomogeneity and anisotropy in metallic materials fabricated by additive manufacturing. In this study, a phased array ultrasonic method is developed to characterize the inhomogeneity and anisotropy of wire and arc additively manufactured components by performing both beams focusing and steering. Two backscattering features, i.e., the integrated backscattering intensity and the root mean square of the backscattering signals, are employed to quantify the microstructural inhomogeneity and anisotropy, respectively. An experimental investigation is performed using an aluminum sample fabricated by wire and arc additive manufacturing. The ultrasonic measurements, performed on wire and arc additive manufactured 2319 aluminum alloy, show that the sample is inhomogeneous and weakly anisotropic. Metallography, electron backscatter diffraction, and X-ray computed tomography are used to verify the ultrasonic results. An ultrasonic scattering model is used to identify the influence of grains on the backscattering coefficient. Compared with a wrought aluminum alloy, the complex microstructure in additively manufactured material significantly influence the backscattering coefficient, and the presence of pores cannot be neglected in ultrasonic-based nondestructive evaluation for wire and arc additive manufactured metals.
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In this paper, a review of the current status and future perspectives for reinforced glass fiber waste is undertaken, as well as an evaluation of the management hierarchy for these end-of-life materials. Waste levels are expected to increase in the coming years, but an improvement of collection routes is still necessary. The recycling processes for these materials are presented. The associated advantages and disadvantages, as well as the corresponding mechanical characteristics, are described. Although mechanical shredding is currently the most used process, there is a potential for thermal processes to be more competitive than others due to the fiber quality after the recycling process. However, the energy requirements of each of the processes are not yet well explained, which compromises the determination of the economic value of the recycled fibers when included in other products, as well as the process feasibility. Nevertheless, the work of some authors that successfully integrated recycled glass fibers into other elements with increased mechanical properties is evaluated. Future recommendations for the recycling of glass fiber and its commercialization are made.
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Forty crossbred (Santa Ines × Dorper) male lambs were used to investigate the effect of dietary buriti oil (BOIL) intake on meat quality, fatty acid (FA) composition and sensory attributes. A completely randomized design with five BOIL intake levels (0, 12, 24, 36 and 48 g/kg DM) was used. Increasing dietary BOIL intake linearly reduced the DMI, slaughter weight, cooking loss, shear force, yellowness, 16:0, c9-18:1 FA concentrations, and the delta-9-desaturase activity index computed using c9-16:1 and 16:0 as product and substrate pair, cis-MUFA and Æ©MUFA/Æ©SFA ratio of lamb meat (P ≤ 0.05); however, increasing dietary BOIL intake quadratically increased the energy intake, lipid content and linearly increased the total FA intake, chroma, collagen, total BI, 18:0, 20:3n-6 concentration and sensory attributes of lamb meat (P ≤ 0.05), without affecting health indexes regarding fat consumption. BOIL addition at levels above 24 g/kg DM in lamb diet reduces growth, however, improves tenderness, flavor and "goat" aroma intensity and slightly changes meat FA levels, promoting better acceptance by panelists.
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Grasas Insaturadas en la Dieta , Carne Roja , Alimentación Animal/análisis , Animales , Carotenoides , Dieta/veterinaria , Ácidos Grasos , Masculino , Carne/análisis , Aceites de Plantas , Carne Roja/análisis , OvinosRESUMEN
Superelastic NiTi alloy and 304 stainless steel (304 SS) were joined with a Cu interlayer by ultrasonic spot welding (USW) using different welding energy inputs. The surface morphology, interfacial microstructure, mechanical properties, and fracture mechanisms of the dissimilar NiTi/304 SS USWed joints were studied. The results showed that the surface oxidation intensified with increasing ultrasonic welding energy due to mutual rubbing between tools and sheets. The weld interface microstructure exhibited voids or unbonded zones at low energy inputs, while an intimate contact was established at the joining interface when applying a higher energy input of 750 J. With increasing energy input to 750 J, the weld interface shows two interfaces due to the behavior of plastic flow of Cu interlayer. The lap-shear load of the joints first increased, achieving a maximum value of â¼690 N at an energy input of 750 J, and then decreased with further increase in welding energy. Interfacial failure was observed at NiTi/Cu interface at all energy inputs, and no intermetallic compounds were found on the fracture surfaces of both the NiTi/Cu and Cu/304 SS interfaces.
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The aim of this study was to evaluate the productive and reproductive performance of dairy goat genotypes, as well as the influence of hygienic practices by farmers on the quality of goat milk. Productive and reproductive data of 81 Anglo Nubian and Alpine crossbred goats, as well as data on total milk production of goats over 100 days of lactation and partial production up to 56 days of lactation. Also, in natura milk samples from 160 properties in the region were evaluated. At the time of collection, a questionnaire was applied to diagnose goat milk production systems. Data from productive and reproductive performance were evaluated by Tukey test and descriptive analysis using the SPSS program. The herd presented a variation of the total milk production in lactation (TMP) from 267.40kg to 468.55kg, with lactation length ranging from 157 to 247 days, and average daily production between 1.43 and 1.89kg/day. Fertility rates were satisfactory, with the lowest rate being 76% and the highest 92%, with an average of 85.24% considering the six seasons of birth. The means of the gestation periods varied between 144 and 152 days. Regarding the sanitary characterization, 73% of farmers performed a cleaning of the room before and after milking. However, 94.8% of farmers did not eliminate the first jets of milk and only 29.2% used the screened mug test to identify clinical mastitis. Only 41% of farmers performed pre and post-dipping and 30.2% applied the iodine solution. Only 8.3% of farmers used disposable paper towels. However, 92% of producers still used fabric towel. It was also observed that 99% of the properties stored milk in buckets or cans without refrigeration. In the microbiological analysis, a small amount of milk samples (5.6%) was contaminated with Staphylococcus aureus, however the total coliform count was high. Regarding the somatic cell count, it was found that 86% of the properties presented values above one million cells per mL of sample. The study demonstrated the prevalence of several factors that contribute to the vulnerability of milk contamination in various stages of production such as milking and processing. Thus, the guidance and awareness of those responsible is extremely important to improve goat milk quality in the semi-arid region of Paraíba.(AU)
O objetivo do presente estudo foi avaliar o desempenho produtivo e reprodutivo de genótipos caprinos leiteiros, assim como a influência da adoção das práticas higiênicas pelos produtores sobre a qualidade do leite caprino. A primeira parte da pesquisa foi realizada na Estação Experimental Pendência-PB. Foram analisados dados produtivos e reprodutivos de 81 cabras Anglo-Nubiana e alpinas mestiças, bem como dados de produção total de leite das cabras acima de 100 dias de lactação e produção parcial até 56 dias de lactação. Também foram avaliadas amostras de leite in natura de 160 propriedades da região. No momento da coleta, foi aplicado um questionário de diagnóstico dos sistemas de produção de leite caprino. Os dados de desempenho produtivo e reprodutivo foram avaliados pelo teste de Tukey e pela análise descritiva utilizando o programa SPSS. O rebanho apresentou uma variação da produção de leite total na lactação desde 267,40kg a 468,55kg, com durações de lactação variando de 157 e 247 dias, e produção média diária entre 1,43 e 1,89kg/dia. As taxas de fertilidade foram satisfatórias, sendo a menor taxa de 76% e a maior de 92%, com uma média de 85,24% considerando as seis estações de parição. As médias dos períodos de gestação variaram entre 144 e 152 dias. Quanto à caracterização da sanidade, 73% dos produtores realizam limpeza da sala antes e após a ordenha. No entanto, 94,8% dos produtores não eliminam os primeiros jatos de leite e somente 29,2% utilizam o teste da caneca telada para identificação de mastite clínica. Apenas 41% dos produtores realizam pré-dipping e pós-dipping e 30,2% aplicam a solução de iodo. Somente 8,3% dos produtores usam toalhas descartáveis e 92% ainda utilizam toalha de tecido. Observou-se, ainda, que 99% das propriedades armazenam o leite ordenhado em baldes ou latões, sem refrigeração. Pequenas quantidades de amostras (5,6%) estavam contaminadas por Staphylococcus aureus, porém a contagem de coliformes totais teve valor elevado. Em relação à contagem de células somáticas, verificou-se que 86% das propriedades apresentaram CCS acima de um milhão de células por mL, devendo-se ajustar corretamente os manejos alimentar, produtivo e reprodutivo. As épocas de parição, lactação e o genótipo influenciaram de forma direta os índices produtivos e reprodutivos dos animais. Obsevou-se a prevalência de vários fatores que contribuem para a vulnerabilidade de contaminação do leite em diversas etapas de produção, tais como ordenha e processamento. Portanto, a orientação adequada e a conscientização dos responsáveis são de extrema importância para melhorar a qualidade do leite de cabra na região semiárida da Paraíba.(AU)
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Animales , Femenino , Cabras , Contaminación de Alimentos/análisis , Leche/microbiología , Leche/química , Lactancia , Higiene Alimentaria , EficienciaRESUMEN
BACKGROUND: Recent years have witnessed a considerable increase in clinical trials of new investigational agents for Fabry disease (FD). Several trials investigating different agents are currently in progress; however, lack of standardisation results in challenges to interpretation and comparison. To facilitate the standardisation of investigational programs, we have developed a common framework for future clinical trials in FD. METHODS AND FINDINGS: A broad consensus regarding clinical outcomes and ways to measure them was obtained via the Delphi methodology. 35 FD clinical experts from 4 continents, representing 3389 FD patients, participated in 3 rounds of Delphi procedure. The aim was to reach a consensus regarding clinical trial design, best treatment comparator, clinical outcomes, measurement of those clinical outcomes and inclusion and exclusion criteria. Consensus results of this initiative included: the selection of the adaptative clinical trial as the ideal study design and agalsidase beta as ideal comparator treatment due to its longstanding use in FD. Renal and cardiac outcomes, such as glomerular filtration rate, proteinuria and left ventricular mass index, were prioritised, whereas neurological outcomes including cerebrovascular and white matter lesions were dismissed as a primary or secondary outcome measure. Besides, there was a consensus regarding the importance of patient-related outcomes such as general quality of life, pain, and gastrointestinal symptoms. Also, unity about lysoGb3 and Gb3 tissue deposits as useful surrogate markers of the disease was obtained. The group recognised that cardiac T1 mapping still has potential but requires further development before its widespread introduction in clinical trials. Finally, patients with end-stage renal disease or renal transplant should be excluded unless a particular group for them is created inside the clinical trial. CONCLUSION: This consensus will help to shape the future of clinical trials in FD. We note that the FDA has, coincidentally, recently published draft guidelines on clinical trials in FD and welcome this contribution.
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Ensayos Clínicos como Asunto , Terapia de Reemplazo Enzimático , Enfermedad de Fabry/tratamiento farmacológico , Riñón/metabolismo , Adulto , Consenso , Técnica Delphi , Enfermedad de Fabry/genética , Enfermedad de Fabry/metabolismo , Enfermedad de Fabry/patología , Femenino , Globósidos/uso terapéutico , Glucolípidos/uso terapéutico , Humanos , Isoenzimas/genética , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Persona de Mediana Edad , Calidad de Vida , Esfingolípidos/uso terapéutico , Resultado del Tratamiento , Trihexosilceramidas/uso terapéutico , alfa-Galactosidasa/genéticaRESUMEN
Utilizaram-se quatro garanhões nos meses de janeiro, abril, julho e outubro de 2016, em dois protocolos, em que: GI (n=4; 5mL de solução salina, i.v.) e GII (n=4; 5000UI de hCG, i.v.) e subdividiram-se esses protocolos em ciclos (C1 e C2), seguindo o esquema crossover, sendo: CI=animais 1 (GI) e 2 (GII), avaliados nos dias D1, D3 e D5, e animais 3 (GI) e 4 (GII), em D2, D4 e D6; CII= animais 1 (GII) e 2 (GI), em D1, D3, D5, e animais 3 (GII) e 4 (GI), em D2, D4 e D6. Realizou-se o tratamento em D1 e D2 de cada ciclo e a ultrassonografia testicular no modo color Doppler e Doppler espectral, uma hora antes de cada coleta de sêmen e imediatamente após. Avaliou-se: número de reflexo de Flehmen, de montas sem ereção, início da monta, tempo de reação à ereção e total da monta e análises de qualidade seminal. Estatisticamente foram utilizados os testes de qui-quadrado e ANOVA. Não houve diferenças estatísticas (P>0,05) entre os parâmetros analisados. Concluiu-se que uma única dose de 5000UI de hCG em garanhões não causou alterações significativas nos parâmetros avaliados em diferentes estações do ano.(AU)
Four stallions were used in January, April, July and October 2016 in two protocols: GI (n=4; 5ml saline, iv) and GII (n=4; 5000 hCG, iv), and these protocols were subdivided into cycles (C1 and C2) following the cross over scheme, as follows: CI=animal 1 (GI) and 2 (GII) evaluated on days D1, D3 and D5 and animal 3 (GI) and 4 (GII) at D 2, D 4 and D 6; CII=animal 1 (GII) and 2 (GI) at D1, D3, D5 and animal 3 (GII) and 4 (GI) at D2, D4 and D6. Treatment was performed on D1 and D2 of each cycle and testicular ultrasound in color Doppler and spectral Doppler mode, one hour before each semen collection and immediately after. We evaluated: Flehmen's reflex number, mounts without erection, start of the mount, reaction time to erection and total mount and seminal quality analyzes. Statistically, the Chi-square and ANOVA tests were used. There were no statistical differences (P>0.05) between the analyzed parameters. It was concluded that a single dose of 5000IU hCG in stallions did not cause significant changes in the parameters evaluated in different seasons of the year.(AU)
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Animales , Masculino , Testículo/diagnóstico por imagen , Gonadotropina Coriónica/administración & dosificación , Caballos/fisiología , Estaciones del Año , Ultrasonografía Doppler en Color/veterinariaRESUMEN
The objective for this study was to evaluate the supplementation with different non-fibrous carbohydrate (NFC) sources for grazing dairy cows in diets with high or low concentrations of rumen undegradable protein (RUP). Twelve multiparous cows averaging 30kg/d of milk production and 45±23 days in milk in a 4x4 Latin square design with 2 × 2 factorial arrangement were used. The difference in NFC content of the diets was achieved using ground corn (GC) or dried citrus pulp (DCP). Dietary RUP was altered by the partial replacement of soybean meal (LRUP) by roasted whole soybean and corn gluten meal (HRUP). Greater dry matter intake (DMI) was observed in DCP treatments compared to GC treatments (19.2 and 17.7kg/day of DM, respectively). Milk fat concentration was lower for LRUP treatments (3.4%) when compared to HRUP (3.6%). The milk protein concentration was greater for GC treatments (2.9%) in relation to DCP treatments (2.8%). Lower milk ureic nitrogen was observed when DCP diets were fed compared to those with GC (17.8 and 21.2mg/dL, respectively). The use of DCP as CNF source increased dry matter intake as well as milk fat concentration, although no differences in milk production were observed for RUP level.(AU)
Objetivou-se avaliar a suplementação com diferentes fontes de carboidratos não fibrosos (CNF) em vacas manejadas a pasto em dietas com alta ou baixa concentração de proteína não degradável no rúmen (PNDR). Doze vacas multíparas com média de 30kg leite/ dia e 45±23 dias em lactação foram utilizadas em delineamento quadrado latino 4x4 com arranjo fatorial 2 × 2. As fontes de CNF foram milho moído (MM) e polpa cítrica seca (PC). A PNDR da dieta foi alterada pela substituição parcial do farelo de soja da dieta de baixa PNDR (BPNDR) por grão de soja tostado e farelo de glúten de milho dieta de alta PNDR (APNDR). Foi observado maior consumo de matéria seca (CMS) nos tratamentos com PC quando comparado aos tratamentos com MM (19,2 e 17,7kg / dia de MS, respectivamente). O teor de gordura do leite foi menor para os tratamentos com BPNDR (3,4%) em comparação aos tratamentos com APNDR (3,6%). O teor de proteína do leite foi maior nos tratamentos com MM (2,9%) em relação aos tratamentos com PC (2,8%). Foram observados menores teores de nitrogênio ureico no leite dos animais alimentados com PC em relação aos com MM (17,8 e 21,2mg / dL, respectivamente). O uso de PC como fonte de CNF aumentou o consumo de matéria seca, bem como o teor de gordura do leite, embora não tenham sido observadas diferenças na produção de leite relacionada a alteração nos teores de PNDR.(AU)
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Animales , Femenino , Bovinos , Carbohidratos de la Dieta/administración & dosificación , Pectinas , Panicum , RumenRESUMEN
We demonstrated that classical biophysical measurements of water dynamics on germinating diaspores (seeds and other dispersal units) can improve the understanding of the germination process in a simpler, safer, and newer way. This was done using diaspores of cultivated species as a biological model. To calculate the water dynamics measurements (weighted mass, initial diffusion coefficient, velocity, and acceleration), we used the mass of diaspores recorded over germination time. Weighted mass of germinating diaspores has a similar pattern, independent of the physiological quality, species, or genetic improvement degree. However, the initial diffusion coefficient (related to imbibition per se), velocity, and acceleration (related to the whole germination metabolism) are influenced by species characters, highlighting the degree of genetic improvement and physiological quality. Changes in the inflection of velocity curves demonstrated each phase of germination sensu stricto. There is no pattern related to the number of these phases, which could range between three and six. Regression models can demonstrate initial velocity and velocity increments for each phase, giving an idea of the management of germinative metabolism. Our finds demonstrated that germination is a polyphasic process with a species-specific pattern but still set by the degree of genetic improvement and (or) physiological quality of diaspores. Among the biophysical measurements, velocity has the greatest potential to define the germination metabolism.
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Objectives: The objective of this study was the evaluation of the professional exposure to nanoparticles during tasks performed in workstations for production of metallic parts by laser welding additive manufacturing. Materials and methods: The study was developed in an installed additive manufacturing machine, having controlled temperature and humidity in an industrial unit where metal parts were being produced using stainless steel powders of granulometry of 10 to 35 µm. Results and discussion: Monitoring of airborne nanoparticles emission was made using adequate equipment, which showed considerable number of nanoparticles over the baseline, having the same composition as the steel powder used. Conclusion: It is concluded that the values of professional exposure to nanoparticles are high in these workstations and that the nanoparticles to which the workers are exposed are small in size (around 15 nm), thus having a strong capacity for alveolar penetration and, consequently, with a strong possibility of passing to the bloodstream, accumulating in the body.
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Contaminantes Ocupacionales del Aire/análisis , Nanopartículas/análisis , Exposición Profesional/análisis , Acero Inoxidable , Soldadura , Monitoreo del Ambiente , Humanos , PolvosRESUMEN
Additive manufacturing has revolutionized the manufacturing paradigm in recent years due to the possibility of creating complex shaped three-dimensional parts which can be difficult or impossible to obtain by conventional manufacturing processes. Among the different additive manufacturing techniques, wire and arc additive manufacturing (WAAM) is suitable to produce large metallic parts owing to the high deposition rates achieved, which are significantly larger than powder-bed techniques, for example. The interest in WAAM is steadily increasing, and consequently, significant research efforts are underway. This review paper aims to provide an overview of the most significant achievements in WAAM, highlighting process developments and variants to control the microstructure, mechanical properties, and defect generation in the as-built parts; the most relevant engineering materials used; the main deposition strategies adopted to minimize residual stresses and the effect of post-processing heat treatments to improve the mechanical properties of the parts. An important aspect that still hinders this technology is certification and nondestructive testing of the parts, and this is discussed. Finally, a general perspective of future advancements is presented.
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Abstract Typha domingensis (cattail) is a native macrophyte known by its capacity to tolerate several heavy metals effects and the potential use for phytoremediation. However, in despite that cadmium (Cd) is one of the most toxic pollutants; its effects in T. domingensis biology remain uninvestigated. Thus, the objective of this study was to study the tolerance of T. domingensis to cadmium contamination by evaluating its growth, Cd uptake, leaf anatomy and gas exchange. The experiment was designed using three cadmium concentrations (0, 10 and 50 µM) and ten replicates for 90 days. The cadmium uptake, growth, gas exchange, chlorophyll content and leaf anatomy were evaluated. Data was submitted to ANOVA and Scott-Knott test for P<0.05. Typha domingensis accumulates Cd proportionally to its concentration on the solution and the content of this metal was higher in roots as compared to shoots. Plants showed no significant modifications on growth parameters such as the biomass production, number of leaves, number of clones and the biomass allocation to organs. The photosynthesis, transpiration and chlorophyll content were not modified by Cd. Most anatomical traits evaluated were not modified by the metal but the stomatal density and the proportion of vascular tissues were reduced under 50 µM of Cd. In despite, the leaf anatomy showed no toxicity evidences for any Cd level. The absence of growth reduction and the stability of anatomical and physiological traits give insight about the Cd tolerance of this species. Therefore, T. domingensis is able to overcome Cd toxicity and shows potential for phytoremediation.
Resumo A espécie Typha domingensis (taboa) é uma macrófita nativa conhecida por sua tolerância a vários metais pesados e potencial uso na fitorremediação. Contudo, apesar de que o Cd é um dos poluentes mais tóxicos; Seus efeitos em T. domingensis ainda não foram investigados. Assim, o objetivo desse estudo foi avaliar a tolerância de T. domingensis ao cádmio, avaliando o crescimento, absorção de Cd, anatomia foliar e trocas gasosas. O experimento foi conduzido utilizando três concentrações de Cd (0, 10 e 50 µM) e dez repetições por 90 dias.. O crescimento, trocas gasosas e o teor de clorofila e anatomia foliar foram avaliados. Os dados foram submetidos à ANOVA e ao teste de Scott-Knott para P<0,05. A absorção de cádmio, crescimento, trocas gasosas, teor de clorofila e anatomia foliar foram analisados. As plantas de T. domingensis podem acumular Cd proporcionalmente à sua concentração na solução e o teor deste metal foi maior nas raízes em comparação com a parte aérea. As plantas não apresentam modificações significativas nos parâmetros de crescimento como produção de biomassa, número de folhas, número de clones produzidos e alocação de biomassa nos órgãos. A fotossíntese, transpiração e conteúdo de clorofila não foram afetados de forma significativa pelo Cd. A maioria das características anatômicas avaliadas não apresentou diferenças, mas houve redução na densidade estomática e na proporção de tecidos vasculares na concentração de 50 µM de Cd. A anatomia foliar não mostrou evidências de toxicidade em nenhum dos níveis de Cd. A ausência de redução de crescimento e estabilidade das características anatômicas e fisiológicas caracteriza alta tolerância da espécie ao Cd. Portanto, T. domingensis é capaz de superar a toxicidade do Cd e demostra potencial para fitorremediação.
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Cadmio/metabolismo , Hojas de la Planta/metabolismo , Typhaceae/crecimiento & desarrollo , Typhaceae/metabolismo , Fotosíntesis/fisiología , Biodegradación Ambiental , Cadmio/toxicidad , Clorofila/metabolismo , Clorofila/química , Raíces de Plantas/metabolismo , Raíces de Plantas/química , Hojas de la Planta/química , Biomasa , Relación Dosis-Respuesta a DrogaRESUMEN
Typha domingensis (cattail) is a native macrophyte known by its capacity to tolerate several heavy metals effects and the potential use for phytoremediation. However, in despite that cadmium (Cd) is one of the most toxic pollutants; its effects in T. domingensis biology remain uninvestigated. Thus, the objective of this study was to study the tolerance of T. domingensis to cadmium contamination by evaluating its growth, Cd uptake, leaf anatomy and gas exchange. The experiment was designed using three cadmium concentrations (0, 10 and 50 µM) and ten replicates for 90 days. The cadmium uptake, growth, gas exchange, chlorophyll content and leaf anatomy were evaluated. Data was submitted to ANOVA and Scott-Knott test for P<0.05. Typha domingensis accumulates Cd proportionally to its concentration on the solution and the content of this metal was higher in roots as compared to shoots. Plants showed no significant modifications on growth parameters such as the biomass production, number of leaves, number of clones and the biomass allocation to organs. The photosynthesis, transpiration and chlorophyll content were not modified by Cd. Most anatomical traits evaluated were not modified by the metal but the stomatal density and the proportion of vascular tissues were reduced under 50 µM of Cd. In despite, the leaf anatomy showed no toxicity evidences for any Cd level. The absence of growth reduction and the stability of anatomical and physiological traits give insight about the Cd tolerance of this species. Therefore, T. domingensis is able to overcome Cd toxicity and shows potential for phytoremediation.
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Cadmio/metabolismo , Hojas de la Planta/metabolismo , Typhaceae/crecimiento & desarrollo , Typhaceae/metabolismo , Biodegradación Ambiental , Biomasa , Cadmio/toxicidad , Clorofila/química , Clorofila/metabolismo , Relación Dosis-Respuesta a Droga , Fotosíntesis/fisiología , Hojas de la Planta/química , Raíces de Plantas/química , Raíces de Plantas/metabolismoRESUMEN
Even though exhaustively studied, dormancy alleviation in diaspores of Urochloa humidicola (Rendle) Morrone & Zuloaga remains a mystery. To clarify this, we asked the following question: could dormancy alleviation in diaspores of this species be associated with ageing, GA/ABA balance and remaining structures of the panicoid spikelet? We answer this question using diaspores of U. humidicola cv. BRS Tupi as a biological model, a cultivar with a wide edaphoclimatic range in Neotropical areas and whose diaspores possess 'deep dormancy' when dispersed. We analysed both germination and early plant development using a split-plot model. Our findings demonstrate that dormancy alleviation in diaspores of U. humidicola is a synergic phenomenon driven by crosstalk between age, GA/ABA balance and remaining structures of the panicoid spikelet covering caryopses, since this interaction acts on the dynamics of germination and early plant development. We demonstrate that: (i) spreading germination time is a maternal survival mechanism of this species, which has repercussions for occupational aggressiveness of the species; (ii) remaining structures of the panicoid spikelet covering caryopses are the main modulator of embryo development. These structures control the after-ripening process, which is modulated by some molecular factor. We also highlight that it is necessary to review concepts about dormancy of dispersal units in this grass species.
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Latencia en las Plantas/fisiología , Poaceae/fisiología , Dispersión de Semillas , Ecología , Germinación/fisiología , Poaceae/anatomía & histología , Semillas/anatomía & histología , Semillas/fisiología , Clima Tropical , Agua/metabolismoRESUMEN
Este estudo objetivou avaliar os efeitos da inoculação de proteína isolada de soja (P.I.S.) em ovos embrionados de matrizes semipesadas com diferentes idades. Foram utilizados 320 ovos embrionados de matrizes semipesadas da linhagem Rhode Island Red com 35 e 70 semanas de idade. Ao 17º dia de incubação, os ovos foram inoculados com 0,5mL de solução diretamente na cavidade alantoide. O delineamento experimental utilizado foi o inteiramente ao acaso, em esquema fatorial (2 x 4), constituído por dois fatores: idades das matrizes (matrizes jovens e matrizes velhas) e soluções inoculadas (ovo íntegro; 0,5% de solução salina; 1% de P.I.S. + 0,5% de solução salina; e 2% de P.I.S. + 0,5% de solução salina), totalizando oito tratamentos contendo 40 ovos cada. Os dados coletados foram analisados pelo teste de Tukey a 5% de significância. A inoculação de proteína isolada de soja apresentou efeito positivo sobre a relação pinto-ovo, porém sem proporcionar melhora nos rendimentos de incubação, no desenvolvimento dos órgãos e no desempenho de pintos na fase pré-inicial. A idade da matriz influenciou diretamente as variáveis avaliadas, em que ovos oriundos de aves velhas apresentaram maior peso, maior mortalidade embrionária na fase tardia, pintos mais pesados e pior conversão alimentar.(AU)
This study aimed to evaluate the influence of inoculation of isolated soy protein (P.I.S.) in embryonated eggs of semi-heavy with different ages. 320 embryonated eggs were used from semi-heavy breeders of Rhode Island Red lineage with 35 and 70 weeks of age. In the 17th day of incubation, the eggs were inoculated with 0.5 ml of solution in the allantoic cavity. The experimental method was completely randomized in factorial scheme (2 x 4), consisting of two factors: matrices ages (young and old matrices) and inoculation solutions (non-inoculated eggs; 0.5% of saline solution; 1% of P.I.S. + 0.5% of saline solution; and 2% of P.I.S. + 0.5% of saline solution, totalling eight treatments containing 40 eggs each. The inoculation of isolated soy protein showed positive effect on the chick-egg relation, albeit without improving incubation yields, organ development and chicks's performance in the pre-initial phase. The age of the breeder directly influenced the variables evaluated, with eggs from older breeder showing better weight, higher embryonic mortality in late phase, heavier chicks and worse feed conversion.(AU)
Asunto(s)
Animales , Embrión de Pollo/crecimiento & desarrollo , Pollos , Huevos/análisis , Desarrollo Embrionario , Proteínas/análisis , Glycine maxRESUMEN
Leptospira spp., a zoonotic agent relevant for public health, occurs frequently in tropical regions. The aquatic environment represents a viable survival and transmission pathway. This study aimed to investigate the presence of anti-Leptospira spp. antibodies in Phrynops geoffroanus (Geoffroy's side-necked turtle) serum samples using the microagglutination test (MAT), and Leptospira spp. in gastric and cloacal lavage samples using the polymerase chain reaction (PCR) technique. Antibodies against nine different Leptospira spp. serovars were detected in 45.45% (30/66) of the serum samples. Specific amplification of Leptospira spp. genomic material (331bp) was observed in 16.67% (11/66) of the samples. In conclusion, these freshwater testudines host Leptospira spp. and eliminate them. This situation may represent a risk to public health, especially to people who use urban streams for fishing and recreational activities. Additionally, we described some Leptospira spp. serovars, not yet reported in testudines, detected here in P. geoffroanus.