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1.
Healthcare (Basel) ; 11(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37239678

RESUMO

The present work describes the development of a conceptual representation model of the domain of the theory of formal grammars and abstract machines through ontological modeling. The main goal is to develop an ontology capable of deriving new knowledge about the mood of an Alzheimer's patient in the categories of wandering, nervous, depressed, disoriented or bored. The patients are from elderly care centers in Ambato Canton-Ecuador. The population consists of 147 individuals of both sexes, diagnosed with Alzheimer's disease, with ages ranging from 75 to 89 years. The methods used are the taxonomic levels, the semantic categories and the ontological primitives. All these aspects allow the computational generation of an ontological structure, in addition to the use of the proprietary tool Pellet Reasoner as well as Apache NetBeans from Java for process completion. As a result, an ontological model is generated using its instances and Pellet Reasoner to identify the expected effect. It is noted that the ontologies come from the artificial intelligence domain. In this case, they are represented by aspects of real-world context that relate to common vocabularies for humans and applications working in a domain or area of interest.

2.
Rev. bras. ciênc. avic ; 25(3): eRBCA-2023-1801, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1451872

RESUMO

This experiment was conducted for 42 days, and aimed to investigate the effect of conditioning temperature and time on feed quality, performance, jejunum morphology, ileal microbial population, and apparent metabolizable energy in broilers. According to the completely randomized design (CRD) in a factorial arrangement 2*3 (conditioning temperatures: 65 and 75 °C; conditioning times: 30, 60, and 90 second), 540 one-day-old male Ross 308 broilers were randomly distributed among six treatments with six replications, each replicate including 15 birds. Treatments included: 1) 65-30, 2) 65-60, 3) 65-90, 4) 75-30, 5) 75-60, 6) 75-90. The results showed that 60 seconds of conditioning at 75 °C increased the pellet durability index (PDI) in the starter diets (p<0.05). In the grower and finisher diets, groups (65-60) and (65-90) showed the highest PDI (p<0.05). Broilers fed diets conditioned at 75 °C for 60 s showed more body weight gain (p<0.05). On days 25 and 42, the highest villus height (VH) was observed in treatment (75-60), and 60 s steam conditioning increased crypt depth (CD) (p<0.05). At 75 oC, the number of goblet cells decreased, while their highest number was observed at 30 and 60 s on 25 d (p<0.05). Conditioning at 75 °C for 60 s enhanced the apparent metabolizable energy (AME) in broilers (p<0.05). In conclusion, 60 s conditioning at 75 °C improved the PDI of starter diets, performance, villus height, and AME, while the suitable temperature and pelleting time for grower and finisher diets were (65-60) and (65-90).(AU)


Assuntos
Animais , Temperatura , Galinhas/fisiologia , Microbioma Gastrointestinal/fisiologia , Condicionamento Físico Animal
3.
Sci. agric ; 80: e20220243, 2023. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1450488

RESUMO

Top-quality pellets can significantly increase density and durability of agricultural residues, reducing logistic costs. However, these pellets depend on numerous parameters, including feedstock properties and production conditions. To ensure high-quality pellets, a single-factor experiment and the response surface methodology were used to investigate the effects of particle size, moisture content, molding pressure, pelleting time, ultrasonic power, and interaction effects between variables on density and durability of pellets for ultrasonic vibration-assisted pelleting of corn stover. The response surface models between variables and response were established. The results showed that all variables affect the density and durability of pellets. An optimal condition for density and durability was obtained, and a further experiment was conducted to validate the values. The results suggested that desirability (0.999) under optimal conditions confirmed the validation of models. The optimal combination of process parameters included particle size of 1.5 mm, moisture content of 10 %, molding pressure of 379 kPa, pelleting time of 80 s, ultrasonic power of 250 W, with values of 1,381.14 kg m-3 and 97.58 % for density and durability of pellets, respectively.


Assuntos
24444 , Gerenciamento de Resíduos , Zea mays
4.
Animal Model Exp Med ; 5(4): 369-376, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35971614

RESUMO

BACKGROUND: BioCen-128 is a new active pharmaceutical ingredient composed of a specific bovine thymic fraction of a polypeptide nature. Positive results of similar thymus extracts have been shown to be effective in delaying the processes associated with aging, immunosenescence and Alzheimer's disease (AD), where the inflammation plays an important role. Because of the anti-inflammatory potential of BioCen-128, the aim of this study was to evaluate the granuloma model induced by a cotton wool implantation and the model induced by intracerebroventricular (ICV) administration of streptozotocin (STZ). METHOD: The experiment was carried out using male OF-1cenp mice weighing 20 ± 2 g. RESULTS: Mice administered BioCen-128 in via the IP route at 5, 10 and 20 mg/kg of corporal weigh showed a decrease in the wet and dry weights of the granuloma, providing evidence of a systemic anti-inflammatory effect. In the ICV model of STZ, the administration of BioCen-128 improved cognitive function. CONCLUSION: These responses suggested an anti-neuroinflammatory effect explainable by the action of thymosin ß4 and thymosin alfa proteins. The results suggested that BioCen-128 could be used in the prevention and treatment of some diseases, for example AD, where neuroinflammation is one of the biological events that take place.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Animais , Bovinos , Cognição , Modelos Animais de Doenças , Granuloma/tratamento farmacológico , Masculino , Camundongos , Estreptozocina
5.
Arq. bras. med. vet. zootec. (Online) ; 74(4): 677-685, July-Aug. 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1393915

RESUMO

It is known that there is a close relationship between pellet feed size and fish growth. However, the magnitude of this relationship regarding an animals' feed efficiency is not yet clear. Therefore, the present study conducted at the Virginia Tech - Virginia Seafood Agricultural Research and Extension Center (USA), investigated the effects of three different pellet feed sizes, 1.7mm (EP.1), 2.3 mm (EP.2) and 3.1 mm (EP.3), on the growth of Cobia (Rachycentron canadum) in a recirculating aquaculture system (RAS). Animals were farmed for 55 days in 77.5-liter tanks (6 fish with an initial density of 3.78 g L⁻¹) weighing approximately 41.83±1.24g. The results showed that during the 8-week culture period, there were no significant differences between the animal's final weight over the different pellet feed sizes (EP.1 - 952.5±40.7g; EP.2 - 1014.5±26.6g; EP.3 - 1030.0±54.8g). However, biomass gain showed significant differences (EP.1 - 704.0±34+.3g; EP.2 - 763.0±27.8g; EP.3 -776.5±51.9g). Consequently, significant differences were also found in the feed conversion factors.


A relação entre o tamanho do pellet da ração e o crescimento dos peixes é bem conhecida na literatura. No entanto, a magnitude dessa associação em relação à eficiência alimentar dos animais ainda não está clara. Portanto, o presente estudo conduzido na Universidade de Virginia Tech (Virginia Seafood Agricultural Research and Extension Center EUA), investigou os efeitos de três tamanhos diferentes de pellets da ração, 1,7 mm (EP.1), 2,3 mm (EP.2) e 3,1 mm (EP.3), sobre o crescimento de juvenis bijupirá (Rachycentron canadum), em um sistema fechado de recirculação. Os animais foram criados por 55 dias, em tanques de 77,5 litros (densidade inicial de 3,78 g / L), pesando 41,83 ± 1,24 g. Os resultados mostraram que, durante o período de cultivo equivalente a oito semanas, não houve diferenças significativas entre o peso final dos peixes para os diferentes tamanhos de pellets (EP.1 - 952,5 ± 40,7 g; EP.2 - 1014,5 ± 26,6 g; EP.3 - 1030,0 ± 54,8 g). No entanto, o ganho de biomassa mostrou diferenças significativas para o maior pellet quando comparado com o menor (EP.1 - 704,0±34+.3 g; EP.2 - 763,0±27,8 g; EP.3 -776,5±51,9 g). Consequentemente, diferenças significativas também foram encontradas nos fatores de conversão alimentar.


Assuntos
Animais , Aquicultura , Dieta , Pesqueiros , Peixes/crescimento & desenvolvimento
6.
Materials (Basel) ; 15(9)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35591428

RESUMO

The objective of this study was to investigate the production and properties of mixed pellets made from rubberwood (Hevea brasiliensis Muell. Arg) and refuse-derived fuel (RDF) waste with no added binder. Three different conditions of mixed pellets were developed to compare their chemical and physical properties to rubberwood pellets. The produced samples were subjected to both ultimate and proximate analyses. The contents of C, H, N, S, and Cl significantly increased with the increasing amount of refuse-derived fuel in the samples, resulting in reduction of the volatile matter. The mechanical durability of the pellet samples ranged between an average value of 98 and 99%. Mixed pellets containing 50% of rubberwood and 50% of refuse-derived fuel have improved heating values by 22.21% compared to rubberwood pellets. Moreover, mixed pellets having 50% of wood and 50% of refuse-derived fuel had the highest density and the highest energy compared to the other samples. Based on the findings of this study, it appears that the manufactured mixed pellets have the potential to be used as high-energy fuel.

7.
Rev. chil. obstet. ginecol. (En línea) ; Rev. chil. obstet. ginecol;86(6): 516-520, dic. 2021. tab
Artigo em Espanhol | LILACS | ID: biblio-1388692

RESUMO

INTRODUCCIÓN Y OBJETIVO: El rol de la testosterona exógena en la función sexual femenina ha sido estudiado durante muchos años, con resultados contradictorios. En el último tiempo se ha promovido el uso de pellets de testosterona como una solución para mejorar la libido femenina, la cognición, la fuerza muscular y los sistemas cardiovascular y óseo, e incluso evitar el envejecimiento. Por ello, revisamos las publicaciones para tratar de responder si esto es una moda o el tratamiento más innovador del último tiempo. MÉTODO: Se analizaron las bases de datos PubMed/Medline, Trip Database, Cochrane, SciELO, Scopus, UpToDate, Ovid, ProQuest, Science Direct y ResearchGate. RESULTADOS: De acuerdo con la evidencia, la mejor testosterona disponible es la transdérmica y debe ser usada solo en el trastorno del deseo sexual hipoactivo (TDSH). Los trabajos que evalúan los pellets de testosterona tienen sesgos metodológicos importantes. Si bien son útiles para mejorar la función sexual femenina, producen concentraciones plasmáticas suprafisiológicas de testosterona, por lo que no se puede establecer su seguridad a largo plazo. Tampoco hay datos suficientes que avalen su uso para mejorar el rendimiento cognitivo y el bienestar general, en el tratamiento de enfermedades cardiovasculares o en la prevención de enfermedad ósea. CONCLUSIONES: La testosterona solo se recomienda en el tratamiento del TDSH por vía transdérmica. No recomendamos el uso de pellets de testosterona para el tratamiento de la disfunción sexual ni como hormona antienvejecimiento, ya que no hay estudios consistentes sobre su seguridad, eficacia y efectos adversos a largo plazo.


INTRODUCTION AND OBJECTIVE: The role of exogenous testosterone in female sexual function has been studied for many years with contradictory results. In recent times, the use of testosterone pellets has been promoted as a solution to improve female libido, cognition, muscle strength, cardiovascular system, bone and even prevent aging. Therefore, we will review the publications in order to answer whether this is a fad or the most innovative treatment of recent times. METHOD: The databases PubMed/Medline, Trip Database, Cochrane, SciELO, Scopus, UpToDate, Ovid, ProQuest, Science Direct and ResearchGate were analyzed. RESULTS: So far, the evidence best testosterone available is transdermal testosterone and that it should be used only in hypoactive sexual desire disorder (HSDD). Papers evaluating testosterone pellets have significant methodological biases. While they are useful in improving female sexual function, they produce supra-physiological plasma levels of testosterone, so their long-term safety cannot be established. There is also insufficient data to support their use in improving cognitive performance and general well-being, treatment of cardiovascular disease or prevention of bone disease. CONCLUSIONS: Testosterone is only recommended for the tratment of HSDD via the transdermal route. We do not recommended the use of testosterone pellets for the treatment of sexual dysfunction or as an anti aging hormone, as there are no consistent studies on its safety, efficacy, and long-term adverse effects.


Assuntos
Humanos , Feminino , Testosterona/administração & dosagem , Disfunções Sexuais Psicogênicas/tratamento farmacológico , Implantes de Medicamento , Androgênios/biossíntese
8.
Semina ciênc. agrar ; 42(06): 3185-3200, nov.-dez. 2021. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1501899

RESUMO

Boron (B) deficiency is commonly found in tropical crops, among which sorghum stands out for its limited yield under B shortage. However, as a micronutrient, the range between its adequate and toxic levels is narrow, thus fertilization should be cautiously applied. Our goal was to evaluate the physiological and physical quality, as well as early performance, of grain sorghum seedlings under different B doses applied via seeds. Treatments consisted of six doses of boric acid (0.0, 2.5, 5.0, 7.5, 10.0, and 12.5 g Kg-¹ seeds) plus a control (uncoated seeds). Boron doses were applied to seeds by coating, in which dolomitic limestone and glue were used for pellet formation. Coated seeds were assessed for physical, physiological, and nutritional characteristics in the laboratory, and early seedling performance was evaluated in a greenhouse. Seed tests were carried out in a fully randomized design, while seedling evaluations were carried out in a randomized block design. Boron application to seeds had no significant effect on seed physical characteristics, despite increases in coated seed sizes. Boron doses had a negative effect on the length and dry mass accumulation of both plant shoot and root. Seed-applied B accumulated mainly in roots and significantly interfered with Ca and Mg accumulations in sorghum seeds, shoots, and roots.


O boro é um dos nutrientes que mais promovem deficiência nas culturas das regiões tropicais, dentre elas o sorgo se destaca por ter seu rendimento limitado em condições de insuficiência de boro. Entretanto, por ser um micronutriente o boro apresenta limite estreito entre o teor adequado e o nível de toxicidade sendo exigido uma adubação cautelosa. Objetivou-se avaliar a qualidade fisiológica e física e o desempenho inicial de mudas de sorgo granífero submetidas a diferentes doses de boro via sementes. Foram utilizadas seis doses de ácido bórico (0; 2,5; 5,0; 7,5; 10,0; 12,5 g. Kg-¹ de sementes) mais o tratamento controle(sementes não revestidas). As doses de B foram adicionadas às sementes através do processo de revestimento, onde foi utilizado calcário dolomítico e a cola na formação do pelete. Foram realizadas avaliações físicas, fisiológicas e nutricionais das sementes revestidas e o desenvolvimento inicial das plantas em casa de vegetação. Os testes realizados em laboratório foram conduzidos em delineamento inteiramente casualizado e os realizados em casa de vegetação foram em delineamento de blocos ao acaso. A aplicação de B nas sementes não afetou significativamente as características físicas, entretanto houve incrementos no tamanho das sementes revestidas. As doses de B aplicadas às sementes de sorgo influenciaram negativamente no comprimento e acúmulo de massa seca tanto da parte aérea como da raiz das plantas. O B aplicado nas sementes acumulou-se principalmente nas raízes e interferiu significativamente no acúmulo de Ca e Mg nas sementes, parte aérea e raiz das plantas de sorgo.


Assuntos
Boro/administração & dosagem , Boro/efeitos adversos , Sementes/fisiologia , Sorghum/crescimento & desenvolvimento , Sorghum/fisiologia
9.
Semina Ci. agr. ; 42(06): 3185-3200, nov.-dez. 2021. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-33495

RESUMO

Boron (B) deficiency is commonly found in tropical crops, among which sorghum stands out for its limited yield under B shortage. However, as a micronutrient, the range between its adequate and toxic levels is narrow, thus fertilization should be cautiously applied. Our goal was to evaluate the physiological and physical quality, as well as early performance, of grain sorghum seedlings under different B doses applied via seeds. Treatments consisted of six doses of boric acid (0.0, 2.5, 5.0, 7.5, 10.0, and 12.5 g Kg-¹ seeds) plus a control (uncoated seeds). Boron doses were applied to seeds by coating, in which dolomitic limestone and glue were used for pellet formation. Coated seeds were assessed for physical, physiological, and nutritional characteristics in the laboratory, and early seedling performance was evaluated in a greenhouse. Seed tests were carried out in a fully randomized design, while seedling evaluations were carried out in a randomized block design. Boron application to seeds had no significant effect on seed physical characteristics, despite increases in coated seed sizes. Boron doses had a negative effect on the length and dry mass accumulation of both plant shoot and root. Seed-applied B accumulated mainly in roots and significantly interfered with Ca and Mg accumulations in sorghum seeds, shoots, and roots.(AU)


O boro é um dos nutrientes que mais promovem deficiência nas culturas das regiões tropicais, dentre elas o sorgo se destaca por ter seu rendimento limitado em condições de insuficiência de boro. Entretanto, por ser um micronutriente o boro apresenta limite estreito entre o teor adequado e o nível de toxicidade sendo exigido uma adubação cautelosa. Objetivou-se avaliar a qualidade fisiológica e física e o desempenho inicial de mudas de sorgo granífero submetidas a diferentes doses de boro via sementes. Foram utilizadas seis doses de ácido bórico (0; 2,5; 5,0; 7,5; 10,0; 12,5 g. Kg-¹ de sementes) mais o tratamento controle(sementes não revestidas). As doses de B foram adicionadas às sementes através do processo de revestimento, onde foi utilizado calcário dolomítico e a cola na formação do pelete. Foram realizadas avaliações físicas, fisiológicas e nutricionais das sementes revestidas e o desenvolvimento inicial das plantas em casa de vegetação. Os testes realizados em laboratório foram conduzidos em delineamento inteiramente casualizado e os realizados em casa de vegetação foram em delineamento de blocos ao acaso. A aplicação de B nas sementes não afetou significativamente as características físicas, entretanto houve incrementos no tamanho das sementes revestidas. As doses de B aplicadas às sementes de sorgo influenciaram negativamente no comprimento e acúmulo de massa seca tanto da parte aérea como da raiz das plantas. O B aplicado nas sementes acumulou-se principalmente nas raízes e interferiu significativamente no acúmulo de Ca e Mg nas sementes, parte aérea e raiz das plantas de sorgo.(AU)


Assuntos
Sorghum/crescimento & desenvolvimento , Sorghum/fisiologia , Boro/administração & dosagem , Boro/efeitos adversos , Sementes/fisiologia
10.
J Basic Microbiol ; 61(9): 808-813, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34309880

RESUMO

Granular microsclerotial formulations of entomopathogenic fungi deserve attention because of their post-application, in situ production of new conidia that enhance and prolong mycoinsecticidal efficacy against a target pest insect. Because high ambient moisture is a crucial condition to induce fungal development and conidiogenesis on granules, we tested the impacts of the additions of three humectants-glycerin, propylene glycol, and polyethylene glycol 400-on water absorption by pellets incorporating microsclerotia of Metarhizium humberi IP 46 with microcrystalline cellulose or vermiculite carriers, and on the production of infective conidia of IP 46 microsclerotia in ambient humidities suboptimal for routine conidiogenesis. Glycerin facilitated greater and faster absorption of water than the other humectants. Microcrystalline cellulose absorbed low quantities of water without any added humectant whereas vermiculite did not. IP 46 did not grow or sporulate on pellets prepared with or without glycerin at 86% relative humidity (RH) or on control pellets without glycerin at 91% RH; conidial production on pellets prepared with vermiculite or microcrystalline cellulose and 10% glycerin reached 1.1 × 105 conidia/mg and 1 × 105 conidia/mg, respectively, after 20 days of exposure at 91% RH. Hence, these results strongly support glycerin as a suitable humectant for granular microsclerotial formulations of this fungus.


Assuntos
Higroscópicos/farmacologia , Metarhizium/efeitos dos fármacos , Metarhizium/fisiologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Glicerol/farmacologia , Higroscópicos/classificação , Controle Biológico de Vetores , Propilenoglicol/farmacologia , Água/metabolismo
11.
Int J Adv Manuf Technol ; 115(9-10): 2711-2727, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34092883

RESUMO

This paper presents a systematic review on extrusion additive manufacturing (EAM), with focus on the technological development of screw-assisted systems that can be fed directly with granulated materials. Screw-assisted EAM has gained importance as an enabling technology to expand the range of 3D printing materials, reduce costs associated with feedstock fabrication, and increase the material deposition rate compared to traditional fused filament fabrication (FFF). Many experimental printheads and commercial systems that use some screw-processing mechanism can be found in the literature, but the design diversity and lack of standard terminology make it difficult to determine the most suitable solutions for a given material or application field. Besides, the few previous reviews have offered only a glimpse into the topic, without an in-depth analysis about the design of the extruders and associated capabilities. A systematic procedure was devised to identify the screw-assisted EAM systems that can print directly from granulated materials, resulting in 61 articles describing different pieces of equipment that were categorized as experimental printheads and commercial systems, for small- and large-scale applications. After describing their main characteristics, the most significant extruder modifications were discussed with reference to the materials processed and performance requirements. In the end, a general workflow for the development of 3D printers based on screw extrusion was proposed. This review intends to provide information about the state-of-the-art screw-assisted EAM and help the academy to identify further research opportunities in the field.

12.
Rev. colomb. cienc. pecu ; 34(2): 84-94, Apr.-June 2021. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394932

RESUMO

Abstract Background: The slow-growing chicken strains have particular nutritional and digestive needs, so they may digest pelleted feeds differently compared to commercial strains. Objective: To evaluate performance, digestibility, serum biochemical profile, digestive morphometry, carcass and cut yields of slow-growing broiler chickens fed pelleted feed with different concentrations of fine particles. Methods: A total of 180 slow-growing broiler chicks (Isa Label strain) aged one day were used. The animals were distributed in a completely randomized design with a 2 x 3 factorial scheme (Sex: male or female; Proportion of fine particles: 0, 50, or 100%), with six repetitions of five birds/cage. The birds received water and feed ad libitum during the 28-day experimental period. Results: The proportion of fine particles did not affect the metabolic, digestive or productive variables evaluated. Males showed better overall performance, while females produced better thigh and liver yields. Conclusion: The proportion of fine particles in pelleted feeds did not affect productive or metabolic parameters. Thus, improving pellet quality for slow-growing broilers during the initial rearing phase may not be justified.


Resumen Antecedentes: Los linajes de pollo de crecimiento lento presentan particularidades nutricionales y digestivas; por lo tanto, es posible que aprovechen los alimentos peletizados de manera diferente a los linajes comerciales. Objetivo: evaluar el desempeño, digestibilidad, perfil sérico bioquímico, morfometría digestiva, rendimiento de la carcasa y los cortes de pollos de engorde de crecimiento lento alimentados con raciones peletizadas con diferentes concentraciones de partículas finas. Métodos: Se utilizaron 180 pollitos machos y hembras, de crecimiento lento, de un día de edad, del linaje Isa Label. Los animales se distribuyeron en un diseño completamente aleatorizado y en un esquema factorial 2 x 3 (Sexo: macho y hembras; Proporción de partículas finas en la ración: 0, 50, y 100%) con seis repeticiones de cinco aves/jaula. Las aves recibieron agua y ración ad libitum durante el período de prueba de 28 días. Resultados: la proporción de partículas finas no afectó las variables metabólicas, digestibles y productivas evaluadas. Los machos presentaron mejor desempeño, mientras que las hembras tuvieron mayor rendimiento de muslos e hígado. Conclusión: la proporción de partículas finas en raciones peletizadas no afecta los parámetros productivos y metabólicos. Por lo tanto, probablemente no se justifica mejorar la calidad del pelet para pollos de crecimiento lento en la fase inicial de cría.


Resumo Antecedentes: linhagens de crescimento lento apresentam particularidades nutricionais e digestivas, portanto é possível que aproveitem os alimentos peletizados de maneira diferente das linhagens comerciais. Objetivo: avaliar o desempenho, digestibilidade dos alimentos, o perfil sérico bioquímico, a morfometria digestiva, rendimento de carcaça e cortes de frangos de corte com crescimento lento alimentados com rações peletizadas com diferentes concentrações de partículas finas. Métodos: Foram utilizados 180 pintos de corte, machos e fêmeas de crescimento lento, com um dia de idade, da linhagem Isa Label. Os animais foram distribuídos em delineamento inteiramente casualizado em esquema fatorial 2 x 3 (Sexo: macho e fêmeas; Proporção de partículas finas na ração: 0, 50, e 100%) com seis repetições de cinco aves/gaiola. As aves receberam água e ração ad libtum durante o período experimental de 28 dias. Resultados: a proporção de partículas finas não afetou as variáveis metabólicas, digestórias e produtivas avaliadas. Os machos apresentaram melhor desempenho, enquanto as fêmeas tiverem maior rendimento de coxas e fígado. Conclusão: a proporção de partículas finas nas rações peletizadas não afetaram os parâmetros produtivos e metabólicos e, portanto, não justifica-se melhorias na qualidade de peletes de rações para frangos de crescimento lento na fase inicial de criação.

13.
Braz J Microbiol ; 52(3): 1107-1118, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33876406

RESUMO

Heterologous hosts are highly important to detect the expression of biosynthetic gene clusters that are cryptic or poorly expressed in their natural hosts. To investigate whether actinorhodin-overproducer Streptomyces coelicolor ∆ppk mutant strain could be a possible prototype as a heterologous expression host, a cosmid containing most of the elm gene cluster of Streptomyces olivaceus Tü2353 was integrated into chromosomes of both S. coelicolor A3(2) and ∆ppk strains. Interestingly, it was found that the production of tetracyclic polyketide 8-demethyl-tetracenomycin (8-DMTC) by recombinant strains caused significant changes in the morphology of cells. All the pellets and clumps were disentangled and mycelia were fragmented in the recombinant strains. Moreover, they produce neither pigmented antibiotics nor agarase and did not sporulate. By eliminating the elm biosynthesis genes from the cosmid, we showed that the morphological properties of recombinants were caused by the production of 8-DMTC. Extracellular application of 8-DMTC on S. coelicolor wild-type cells caused a similar phenotype with the 8-DMTC-producing recombinant strains. The results of this study may contribute to the understanding of the effect of 8-DMTC in Streptomyces since the morphological changes that we have observed have not been reported before. It is also valuable in that it provides useful information about the use of Streptomyces as hosts for the heterologous expression of 8-DMTC.


Assuntos
Naftacenos/farmacologia , Streptomyces coelicolor , Streptomyces , Antraquinonas , Antibacterianos , Streptomyces/genética , Streptomyces coelicolor/genética , Streptomyces coelicolor/crescimento & desenvolvimento
14.
Appl Microbiol Biotechnol ; 105(7): 2725-2736, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33745009

RESUMO

The impact of ambient relative humidity (RH) on conidial production of Metarhizium humberi IP 46 microsclerotia (MS) formulated in pellets or granules was investigated, and a promising granular formulation was tested against Aedes aegypti adults to confirm its efficacy. Microcrystalline cellulose (MC) and diatomaceous earth (DE) or a combination of vermiculite (VE), DE and silicon dioxide (SD) were tested as carriers in granular formulations containing MS. A range of 93-96.5% RH was critical for fungal development, and at least 96.5-98.5% RH was required for high conidial production on pellets or granules. Conidial production was clearly higher on pellets and granules prepared with VE than MC as the main carrier. VE granules containing MS were highly active against A. aegypti adults. Most mosquitoes were killed within 6 days after treatment regardless of the exposure time of adults to the formulation (1 min-24 h) or ambient humidity (75 or >98%). Production of conidia on dead adults varied between 7.3 × 106 and 2.2 × 107 conidia/individual, when exposed to MS granules for 12 h and 1 min, respectively. Granular formulations containing VE as the main carrier and MS as the active ingredient of M. humberi have strong potential for use against A. aegypti. KEY POINTS: • High conidial production on granular microsclerotial formulations at >96.5% RH • Vermiculite is more appropriate as a carrier than microcrystalline cellulose • Granules with IP 46 microsclerotia are highly active against Aedes aegypti adults.


Assuntos
Aedes , Metarhizium , Animais , Umidade , Larva , Controle Biológico de Vetores
15.
Environ Entomol ; 50(1): 19-27, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33313693

RESUMO

Carpenter ants (genus Camponotus) are considered to be predominantly omnivorous, mixing several feeding habits that include predation, scavenging of animal matter, and plant-derived resources. Nitrogen acquisition is crucial for the nutritional ecology of ant colonies because growing larvae require sustainable protein provisioning. Here, we investigate the foraging ecology and the spatial nesting structure of the carpenter ant, Camponotus leydigi Forel, in Brazilian cerrado savanna. By marking workers from different nests with distinct colors, we revealed that C. leydigi occupies physically separated but socially connected nests (up to 30 m apart), a phenomenon known as polydomy. Observational data on aboveground internest movements in C. leydigi corroborate cooperative exchanges between nest units and confirm several types of social connections, including internest transfer of liquid and solid food, transport of colony members (brood, workers), movement of solitary workers, and internest recruitment. Polydomous C. leydigi allocate foragers throughout 1,700 m2, feeding mostly on termites and plant-derived exudates. Influx of exudates is threefold higher compared with solid food. Uric acid pellets excreted by lizards comprise 20% of the solid diet in C. leydigi, a rare quantitative assessment of this peculiar type of nitrogen complementation in ants. Based on video recordings, we hypothesize that nest decentralization in C. leydigi may reduce foraging constraints caused by overt interference by the aggressive ant, Ectatomma brunneum Smith, F. (Hymenoptera: Formicidae), which regularly blocks nest entrances. Our field study enhances the importance of natural history data to clarify selective pressures underlying the evolution of particular behavioral patterns (nutritional and nesting habits) in ants.


Assuntos
Formigas , Animais , Brasil , Ecologia , Pradaria , Comportamento Predatório
16.
Semina ciênc. agrar ; 42(6): 3185-3200, nov.-dez. 2021. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1370461

RESUMO

Boron (B) deficiency is commonly found in tropical crops, among which sorghum stands out for its limited yield under B shortage. However, as a micronutrient, the range between its adequate and toxic levels is narrow, thus fertilization should be cautiously applied. Our goal was to evaluate the physiological and physical quality, as well as early performance, of grain sorghum seedlings under different B doses applied via seeds. Treatments consisted of six doses of boric acid (0.0, 2.5, 5.0, 7.5, 10.0, and 12.5 g Kg-1 seeds) plus a control (uncoated seeds). Boron doses were applied to seeds by coating, in which dolomitic limestone and glue were used for pellet formation. Coated seeds were assessed for physical, physiological, and nutritional characteristics in the laboratory, and early seedling performance was evaluated in a greenhouse. Seed tests were carried out in a fully randomized design, while seedling evaluations were carried out in a randomized block design. Boron application to seeds had no significant effect on seed physical characteristics, despite increases in coated seed sizes. Boron doses had a negative effect on the length and dry mass accumulation of both plant shoot and root. Seed-applied B accumulated mainly in roots and significantly interfered with Ca and Mg accumulations in sorghum seeds, shoots, and roots.(AU)


O boro é um dos nutrientes que mais promovem deficiência nas culturas das regiões tropicais, dentre elas o sorgo se destaca por ter seu rendimento limitado em condições de insuficiência de boro. Entretanto, por ser um micronutriente o boro apresenta limite estreito entre o teor adequado e o nível de toxicidade sendo exigido uma adubação cautelosa. Objetivou-se avaliar a qualidade fisiológica e física e o desempenho inicial de mudas de sorgo granífero submetidas a diferentes doses de boro via sementes. Foram utilizadas seis doses de ácido bórico (0; 2,5; 5,0; 7,5; 10,0; 12,5 g. Kg-1 de sementes) mais o tratamento controle (sementes não revestidas). As doses de B foram adicionadas às sementes através do processo de revestimento, onde foi utilizado calcário dolomítico e a cola na formação do pelete. Foram realizadas avaliações físicas, fisiológicas e nutricionais das sementes revestidas e o desenvolvimento inicial das plantas em casa de vegetação. Os testes realizados em laboratório foram conduzidos em delineamento inteiramente casualizado e os realizados em casa de vegetação foram em delineamento de blocos ao acaso. A aplicação de B nas sementes não afetou significativamente as características físicas, entretanto houve incrementos no tamanho das sementes revestidas. As doses de B aplicadas às sementes de sorgo influenciaram negativamente no comprimento e acúmulo de massa seca tanto da parte aérea como da raiz das plantas. O B aplicado nas sementes acumulou-se principalmente nas raízes e interferiu significativamente no acúmulo de Ca e Mg nas sementes, parte aérea e raiz das plantas de sorgo.(AU)


Assuntos
Sementes , Boro/administração & dosagem , Plântula , Sorghum/fisiologia , Fertilização
17.
Sci Total Environ ; 741: 140220, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887000

RESUMO

Human-dominated environments alter the availability and quality of resources for many species, especially for scavengers that have large home ranges and plastic foraging behaviors that enable them to exploit novel resources. Along the western slope of the Andes, the modification of natural landscapes have resulted in significant declines in native prey, the introduction of non-native species, and an increase in the availability of anthropogenic resources. These factors have likely influenced the resources available to Andean condors (Vultur gryphus), however, data are lacking as to how condor's diet vary along their large latitudinal range. We evaluated differences in Andean condor diet along a ~2500 km latitudinal gradient in Chile from the heavily modified Central zone (32-34°S) to the more pristine Austral zone (44-56°S). We assessed diet composition through the identification of prey remains in condor pellets, and carbon and nitrogen isotope analysis of condor feathers and their primary prey identified from pellet analysis. Our results identified medium- and large-bodied domesticated mammals (ungulates) and introduced exotic species (lagomorphs) as common prey across the study area. Condors from the Central zone had the largest isotopic niche width, probably related to consumption of anthropogenic resources with distinctly high carbon isotope values indicative of C4-based foods likely acquired from landfills or corn-fed livestock. Isotopic niches for condors from the Southern and Austral zones almost completely overlapped. Andean condor diet is strongly influenced by local conditions determining differential access to prey sources. The high dependence of Andean condors on livestock across a large geographical area, and landfills in more (sub)urban areas, may help stabilize their populations via anthropogenic resources subsidies. Long-term dependence on such resources, however, may have health costs including contaminant exposure and greater mortality risk. These data will help identify potential threats related to resource availability and use, and better inform management and conservation decisions.


Assuntos
Aves , Comportamento Alimentar , Animais , Chile , Dieta , Plumas , Humanos
18.
Enzyme Microb Technol ; 139: 109587, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32732036

RESUMO

The hydrodynamic environment in bioreactors affects the oxygen transfer rate and the shear conditions during microbial cultivations. Therefore, assessment of the effect of the hydrodynamic environment on cellular morphology can contribute to favoring the production of metabolites of interest. The aim of this work was to use image analysis in order to quantify the fragmentation of Aspergillus niger pellets in a conventional bioreactor operated using different impeller speeds, air flow rates, and impeller configurations including Rushton turbines and Elephant Ear impellers, with evaluation of the influence of the hydrodynamic environment on the production of cellulolytic enzymes. An empirical kinetic model was proposed to describe the dynamics of pellet fragmentation and quantify the shear conditions. The results showed that the agitation speed affected the dynamics of pellet fragmentation in two ways, by accelerating the damage process and by increasing the magnitude of the fragmentation. Both endoglucanase and ß-glucosidase production exhibited a linear relationship with the pellet fragmentation percentage, which was directly related to the shear conditions. Interestingly, ß-glucosidase production was favored under high shear conditions, while the highest endoglucanase production occurred under low shear conditions. These findings may be useful for defining suitable systems and operating conditions for the production of metabolites including enzymes in bioreactors, as well as defining conditions that favour a specific pre-determined enzyme cocktail.


Assuntos
Aspergillus niger/enzimologia , Reatores Biológicos , Celulase/biossíntese , beta-Glucosidase/biossíntese , Fermentação , Hidrodinâmica , Cinética
19.
Electron. j. biotechnol ; Electron. j. biotechnol;40: 58-64, July. 2019. graf, tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1053475

RESUMO

Background: Prodigiosin has been demonstrated to be an important candidate in investigating anticancer drugs and in many other applications in recent years. However, industrial production of prodigiosin has not been achieved. In this study, we found a prodigiosin-producing strain, Serratia marcescens FZSF02, and its fermentation strategies were studied to achieve the maximum yield of prodigiosin. Results: When the culture medium consisted of 16.97 g/L of peanut powder, 16.02 g/L of beef extract, and 11.29 mL/L of olive oil, prodigiosin reached a yield of 13.622 ± 236 mg/L after culturing at 26 °C for 72 h. Furthermore, when 10 mL/L olive oil was added to the fermentation broth at the 24th hour of fermentation, the maximum prodigiosin production of 15,420.9 mg/L was obtained, which was 9.3-fold higher than the initial level before medium optimization. More than 60% of the prodigiosin produced with this optimized fermentation strategy was in the form of pigment pellets. To the best of our knowledge, this is the first report on this phenomenon of pigment pellet formation, which made it much easier to extract prodigiosin at low cost. Prodigiosin was then purified and identified by absorption spectroscopy, HPLC, and LCMS. Purified prodigiosin obtained in this study showed anticancer activity in separate experiments on several human cell cultures: A549, K562, HL60, HepG2, and HCT116. Conclusions: This is a promising strain for producing prodigiosin. The prodigiosin has potential in anticancer medicine studies.


Assuntos
Prodigiosina/biossíntese , Prodigiosina/farmacologia , Serratia marcescens/metabolismo , Antineoplásicos/farmacologia , Arachis/química , Pós , Prodigiosina/isolamento & purificação , Espectrometria de Massas , Células Tumorais Cultivadas/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Técnicas de Cultura de Células , Fermentação , Azeite de Oliva/química , Acetatos , Nitrogênio
20.
Braz. J. Pharm. Sci. (Online) ; 55: e17309, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039050

RESUMO

The intent of the present investigation is to develop and evaluate colon-specific coated tacrolimus solid dispersion pellet (SDP) that retards drug release in the stomach and small intestine but progressively releases in the colon. Tacrolimus-SDP was prepared by extrusion-spheronization technology and optimized by the micromeritic properties including flowability, friability, yields and dissolution rate. Subsequently, the pH-dependent layer (Eudragit L30D55) and time-dependent layer (Eudragit NE30D and L30D55) were coated on the SDP to form tacrolimus colon-specific pellets (CSP) using a fluidized bed coater. Under in vitro gradient pH environment, tacrolimus only released from CSP after changing pH to 6.8 and then quickly released in the phosphate buffer solution of pH 7.2. The Cmax of CSP was 195.68 ± 3.14 ng/mL at Tmax 4.5 ± 0.24 h where as in case of SDP, the Cmax was 646.16 ± 8.15 ng/mL at Tmax 0.5 ± 0.03 h, indicating the ability of CSP targeted to colon. The highest area under the curve was achieved 2479.58 ± 183.33 ng·h/mL for SDP, which was 2.27-fold higher than tacrolimus suspension. However, the best biodistribution performance was achieved from CSP. In conclusion, SDP combining of pH- and time-dependent approaches was suitable for targeted delivery of tacrolimus to colon.


Assuntos
Técnicas In Vitro/classificação , Tacrolimo/análise , Fator de Crescimento de Hepatócito/farmacocinética , Colo/metabolismo , Colite Ulcerativa/prevenção & controle , Sistemas de Liberação de Medicamentos/efeitos adversos , Concentração de Íons de Hidrogênio
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