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1.
Phys Chem Chem Phys ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258915

RESUMO

Graphyne and two-dimensional porous carbon-based materials have garnered significant attention due to their interesting structural characteristics and essential properties for new technological applications. Within this scope, this work investigates the structural, thermal, electronic, optical, and mechanical properties of a novel two-dimensional allotrope that combines triangular (T) and hexagonal (H) rings, connected by acetylenic linkages (graphyne-like), thus named TH-graphyne (TH-GY). This study comprehensively characterizes the proposed system's behavior using density functional theory, ab initio molecular dynamics, and classical reactive molecular dynamics simulations. Our results confirm the structural stability of TH-GY. AIMD simulations demonstrate the material's thermal stability at elevated temperatures, while phonon dispersions indicate its dynamical stability. Electronic band structure calculations show that the system is metallic. The analysis of optical properties reveals intense activity in the visible and UV regions, with pronounced anisotropy. A machine learning interatomic potentials model was developed for TH-GY and used to determine the mechanical behavior of the system, which exhibits Young's modulus ranging from 263 to 356 GPa, highlighting its flexibility. Classical reactive MD simulations elucidate the fracture behavior of TH-GY, revealing distinct fracture patterns and mechanical anisotropy.

2.
Nanoscale ; 16(35): 16430-16438, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39171412

RESUMO

Recently, a new 2D carbon allotrope called Irida-Graphene (Irida-G) was proposed, and its reliable stability has been previously predicted. Irida-G is a flat sheet topologically arranged into 3-6-8 carbon rings exhibiting metallic and non-magnetic properties. In this study, we investigated the thermal transport properties of Irida-G using classical reactive molecular dynamics simulations. The findings indicate that Irida-G has an intrinsic thermal conductivity of approximately 215 W mK-1 at room temperature, significantly lower than that of pristine graphene. This decrease is due to characteristic phonon scattering within Irida-G's porous structure. Additionally, the phonon group velocities and vibrational density of states for Irida-G were analyzed, revealing reduced average phonon group velocities compared to graphene. The thermal conductivity of Irida-G is isotropic and shows significant size effects, transitioning from ballistic to diffusive heat transport regimes as the system length increases. These results suggest that while Irida-G has lower thermal conductivity than graphene, it still holds potential for specific thermal management applications, sharing characteristics with other two-dimensional materials.

3.
iScience ; 27(6): 110121, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38957793

RESUMO

Aerobic exercise training (AET) has emerged as a strategy to reduce cancer mortality, however, the mechanisms explaining AET on tumor development remain unclear. Tumors escape immune detection by generating immunosuppressive microenvironments and impaired T cell function, which is associated with T cell mitochondrial loss. AET improves mitochondrial content and function, thus we tested whether AET would modulate mitochondrial metabolism in tumor-infiltrating lymphocytes (TIL). Balb/c mice were subjected to a treadmill AET protocol prior to CT26 colon carcinoma cells injection and until tumor harvest. Tissue hypoxia, TIL infiltration and effector function, and mitochondrial content, morphology and function were evaluated. AET reduced tumor growth, improved survival, and decreased tumor hypoxia. An increased CD8+ TIL infiltration, IFN-γ and ATP production promoted by AET was correlated with reduced mitochondrial loss in these cells. Collectively, AET decreases tumor growth partially by increasing CD8+ TIL effector function through an improvement in their mitochondrial content and function.

6.
J Mol Model ; 29(10): 328, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773299

RESUMO

CONTEXT: Popgraphene (PopG) is a two-dimensional carbon-based material with fused pentagonal and octagonal rings. Like graphene, it exhibits a metallic band gap and exceptional thermal, dynamic, and mechanical stability. Here, we theoretically study the electronic and structural properties of PopG monolayers, including their doped and vacancy-endowed versions, as O[Formula: see text] adsorbers. Our findings show that pristine and vacancy-endowed PopG sheets have a comparable ability to adsorb O[Formula: see text] molecules, with adsorption energies ranging from [Formula: see text]0.57 to [Formula: see text]0.59 eV (physisorption). In these cases, octagonal rings play a dominant role in the adsorption mechanism. Platinum and Silicon doping enhance the O[Formula: see text] adsorption in areas close to the octagonal rings, resulting in adsorption energies ranging from [Formula: see text]1.13 to [Formula: see text]2.56 eV (chemisorption). Furthermore, we computed the recovery time for the adsorbed O[Formula: see text] molecules. The results suggest that PopG/O[Formula: see text] interaction in pristine and vacancy-endowed cases can change the PopG electronic properties before O[Formula: see text] diffusion. METHODS: Density Functional Theory (DFT) simulations, with Van der Waals corrections (DFT-D, within the Grimme scheme), were performed to study the structural and electronic properties of PopG/O[Formula: see text] systems using the DMol3 code within the Biovia Materials Studio software. The exchange and correlation functions are treated within the generalized gradient approximation (GGA) as parameterized by Perdew-Burke-Ernzerhof (PBE) functional. We used the double-zeta plus polarization (DZP) for the basis set in these cases. We also considered the BSSE correction through the counterpoise method and the nuclei-valence electron interactions by including semi-core DFT pseudopotentials.

7.
World J Hepatol ; 15(5): 688-698, 2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37305375

RESUMO

BACKGROUND: Many studies have been developed with a focus on surgical techniques and drugs, but few that address the importance of rehabilitation in the pre and postoperative period, and the specific benefits for each surgical procedure or type of neoplasm, aiming to minimize respiratory complications in the postoperative period. AIM: To compare the strength of the respiratory muscles in the pre and postoperative periods of hepatectomy by laparotomy and to verify the incidence of postoperative pulmonary complications among the groups studied. METHODS: Prospective, randomized, clinical trial study that compared the inspiratory muscle training group (GTMI) with the control group (CG). After the collection of sociodemographic and clinical data, in both groups, preoperatively, on the first and fifth postoperative days, vital signs and pulmonary mechanics were evaluated and recorded. Albumin and bilirubin values were recorded for the albumin-bilirubin (ALBI) score. After randomization and allocation of participants, those in the CG underwent conventional physical therapy and those in the GTMI underwent conventional physical therapy plus inspiratory muscle, in both groups for five postoperative days. RESULTS: Of 76 subjects met eligibility criteria. The collection of 41 participants was completed: 20 in the CG and 21 in the GTMI. The most frequent diagnosis was 41.5% with liver metastasis, followed by 26.8% with hepatocellular carcinoma. As for respiratory complications in the GTMI, there was no incidence. In the CG, there were three respiratory complications. Patients in the CG classified as ALBI score 3 presented, statistically, a higher energy value compared to patients classified as ALBI score 1 and 2 (P = 0.0187). Respiratory variables, measured preoperatively and on the first postoperative day, had a significant drop in both groups from the preoperative to the first postoperative day (P ≤ 0.0001). When comparing the preoperative period and the fifth postoperative day between the GTMI and the CG, the maximal inspiratory pressure variable in the GTMI was statistically significant (P = 0.0131). CONCLUSION: All respiratory measures showed a reduction in the postoperative period. Respiratory muscle training using the Powerbreathe® device increased maximal inspiratory pressure and this may have contributed to a shorter hospital stay and better clinical outcome.

8.
Front Oncol ; 13: 1237709, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38234397

RESUMO

Background: Even though doxorubicin (DOX) chemotherapy promotes intense muscle wasting, this drug is still widely used in clinical practice due to its remarkable efficiency in managing cancer. On the other hand, intense muscle loss during the oncological treatment is considered a bad prognosis for the disease's evolution and the patient's quality of life. In this sense, strategies that can counteract the muscle wasting induced by DOX are essential. In this study, we evaluated the effectiveness of formoterol (FOR), a ß2-adrenoceptor agonist, in managing muscle wasting caused by DOX. Methods and results: To evaluate the effect of FOR on DOX-induced muscle wasting, mice were treated with DOX (2.5 mg/kg b.w., i.p. administration, twice a week), associated or not to FOR treatment (1 mg/kg b.w., s.c. administration, daily). Control mice received vehicle solution. A combination of FOR treatment with DOX protected against the loss of body weight (p<0.05), muscle mass (p<0.001), and grip force (p<0.001) promoted by chemotherapy. FOR also attenuated muscle wasting (p<0.01) in tumor-bearing mice on chemotherapy. The potential mechanism by which FOR prevented further DOX-induced muscle wasting occurred by regulating Akt/FoxO3a signaling and gene expression of atrogenes in skeletal muscle. Conclusions: Collectively, our results suggest that FOR can be used as a pharmacological strategy for managing muscle wasting induced by DOX. This study provides new insights into the potential therapeutic use of FOR to improve the overall wellbeing of cancer patients undergoing DOX chemotherapy.

9.
Rev. bras. saúde prod. anim ; 24: 20220035, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1431683

RESUMO

Brazilian frog farming has a history of production that began in the state of Rio de Janeiro in 1935. Over the years, this activity has spread throughout Brazil, with technological advances that have improved the productivity and health of enterprises. However, structuring the production chain has presented moments of growth and decline, culminating in low production compared with other aquaculture activities. Despite efforts focused on restructuring the chain, data on enterprises and their actors remain scarce. To obtain information on the current scenario of frog farming in the state of Rio de Janeiro, in this study, an online survey of data on frog producers in Rio de Janeiro was conducted. In general, frog farming in Rio de Janeiro has not shown substantial improvements in terms of structuring. Its dynamics are still linked to lowproduction, family run enterprises, little insertion into the market, and not being formalized, encompassing aspects related to fiscal, environmental, and health issues. Therefore, the restructuring process of the frog chain in the state depends on overcoming the bottlenecks mentioned in this study. These predominantly refer to the availability of information on the relevant aspects of management and regularization of production.(AU)


A ranicultura brasileira apresenta um histórico de produção que se iniciou no estado do Rio de Janeiro em 1935. Com o passar dos anos essa atividade se difundiu para todo o Brasil, apresentando avanços tecnológicos que melhoraram o manejo sanitário e a produtividade dos empreendimentos. Contudo, a estruturação da cadeia produtiva apresentou momentos de crescimento e declínio, culminando com uma baixa produção em comparação com outras atividades aquícolas. Apesar dos esforços focados na reestruturação da cadeia, ainda são escassos dados sobre os empreendimentos e seus atores. Com o objetivo de obter informações acerca do cenário atual da ranicultura no estado do Rio de Janeiro, o presente trabalho executou levantamento de dados referentes aos produtores de rã fluminense por meio de formulário online. De uma maneira geral, a ranicultura no Rio de Janeiro não conseguiu apresentar grandes melhorias em termos de estruturação. Sua dinâmica ainda está atrelada a empreendimentos com baixa produção, familiar, pouca inserção no mercado e não formalizados, englobando aspectos relacionados às questões fiscais, ambientais e sanitárias. Assim, o processo de reestruturação da cadeia ranícola no estado depende da superação dos gargalos apontados neste estudo, principalmente referentes à disponibilização de informação acerca dos aspectos de manejo e regularização da produção.(AU)


Assuntos
Animais , Rana catesbeiana , Aquicultura/métodos , Brasil
10.
Rev. Bras. Odontol. Leg. RBOL ; 9(3): 46-57, 2022-12-30.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1524873

RESUMO

Introdução: O Instagram® é a quarta rede social mais popular em todo o mundo para criar e compartilhar conteúdos editáveis e a mais utilizada para buscar serviços de saúde. Considerando que as redes sociais estão cada vez mais interligadas com a Odontologia e o mercado de trabalho, o objetivo dessa pesquisa foi classificar as estratégias de publicidade utilizadas na rede social Instagram® pelos cirurgiões-dentistas nas áreas de atuação. Material e métodos: Trata-se de um estudo quantitativo, transversal e retrospectivo. Os dados foram prospectados a partir de hashtags relacionadas à Odontologia, em dois períodos diferentes (janeiro/2022) e (março/2022). As postagens foram identificadas por áreas odontológicas e as imagens e/ou legendas classificadas de acordo com a estratégia de publicidade utilizada e realizou-se uma análise descritiva. Resultados: Em relação à imagem, de 1.111 posts, 87,1% (n=965) utilizaram apenas uma estratégia de publicidade e 12,9% de duas a cinco estratégias na mesma postagem. Quanto à legenda, de 529 publicações, 48,4% (n=256) corresponderam a uma estratégia e 51,6% (n=273) de duas até quatro simultaneamente. As estratégias mais frequentes na imagem foram 'lembranças de serviços odontológicos' (29,5%) e 'antes e depois' (16,1%) e, na legenda 'explicativo' (40,1%) e 'lembranças de serviços odontológicos' (31,7%). Conclusão: Áreas que valorizam o resultado estético alcançado, como odontologia integrada, harmonização orofacial, dentística, periodontia, ortodontia e prótese exploram mais o 'antes e depois', enquanto que outras áreas relacionadas ao tratamento e prevenção de doenças estão mais relacionadas a 'lembranças de serviços odontológicos'


Introduction: Instagram® is the fourth most popular social network worldwide to create and share editable content and the most used to search for health services. Considering that social networks are increasingly intertwined with Dentistry and the job market, the objective of this research was to classify the advertising strategies used in the social network Instagram® by dentists in their areas of expertise. Material and method: This is a quantitative, cross-sectional and retrospective study. Data were prospected from hashtags related to Dentistry, in two different periods (January/2022) and (March/2022). The posts were identified by dental areas and the images and/or captions classified according to the advertising strategy used and a descriptive analysis was carried out. Results: Regarding the image, of 1,111 posts, 87.1% (n=965) used only one advertising strategy and 12.9% used two to five strategies in the same post. As for the caption, of 529 publications, 48.4% (n=256) corresponded to one strategy and 51.6% (n=273) from two to four simultaneously. The most frequent strategies in the image were 'souvenirs of dental services' (29.5%) and 'before and after' (16.1%) and, in the caption 'explanatory' (40.1%) and 'souvenirs of dental services ' (31.7%). Conclusion: Areas that value the aesthetic result achieved, such as integrated dentistry, orofacial harmonization, dentistry, periodontics, orthodontics and prosthesis explore more the 'before and after', while other areas related to the treatment and prevention of diseases are more related to 'memories of dental services'

11.
Exp Gerontol ; 166: 111892, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35811017

RESUMO

BACKGROUND: Postural response impairments in postural instability and gait disorders (PIGD) subtype patients may be attributed to Parkinson's disease (PD)-deterioration in central-set (programing/modulating of central outputs during motor responses). Although additional information improves some PD motor impairments, an unanswered question is whether additional information can benefit postural response in PIGD subtype. OBJECTIVE: To analyze the effect of cumulative additional information on postural responses after perturbation in PIGD and neurologically healthy older adults (CG). METHODS: Perturbations were applied in 16 PIGD and 19 CG by the support-base translation. Participants performed 3 blocks of 5 trials without additional information (B1-B3, Day 1) and 5 trials of each cumulative additional information (C1-C4, Day 2): information about perturbation (C1), visual (C2), verbal (C3), and somatosensory information (C4). Electromyography and center of pressure (CoP) parameters were analyzed by ANOVAs with Group (PIGD × CG) and Block (B1 × B2 × B3) and with Group (PIGD × CG) and Condition (B3 × C1 × C2 × C3 × C4). RESULTS: PIGD decreased the range of CoP in B3 while CG decreased both range of CoP and the integral of antagonist's muscle activity (iEMG) in B2. Also, PIGD decreased the recovery time in C4 while CG increased the iEMG of agonist's muscle in C2 and antagonist's muscle in all conditions except C2. CONCLUSION: Additional information provided before postural control assessment influences the postural response in PIGD and CG differently. PIGD demonstrated inflexibility of central-set in modulating the neuromuscular control regardless of additional information. CG presents a flexible system evidenced by the increase of agonist muscle iEMG when provided visual information.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Idoso , Marcha , Humanos , Equilíbrio Postural/fisiologia , Tremor
12.
Einstein (Sao Paulo) ; 20: eAO6935, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35792758

RESUMO

OBJECTIVE: To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group. METHODS: A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded. RESULTS: The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups. CONCLUSION: Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.


Assuntos
Apendicite , Apêndice , Apendicite/diagnóstico por imagem , Apêndice/diagnóstico por imagem , Criança , Estudos Transversais , Humanos , Estudos Retrospectivos , Ultrassonografia
13.
Einstein (São Paulo, Online) ; 20: eAO6935, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384774

RESUMO

ABSTRACT Objective To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group. Methods A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded. Results The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups. Conclusion Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.

14.
Rev. bras. saúde prod. anim ; 23: e2122312021, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1357181

RESUMO

The objective of this study was to evaluate the performance and metamorphosis of bullfrog tadpoles (Lithobates catesbeianus) fed balanced diets, wherein corn flour was replaced with banana, avocado, and pumpkin meal (all made without the epicarp). Using a completely randomized design, the animals were stored in tanks with a capacity of 30 L in a water recirculation system at a density of 1 tadpole/L. Through biweekly biometric measurements, the weight, standard, and total length were evaluated to determine metamorphic development, weight gain, consumption, feed conversion, specific growth rate, survival, physical-chemical parameters of water, and the percentage carcass composition (only at the end). Tadpoles fed rations balanced with pumpkin and banana flour performed the best, followed by those fed avocado meal and those fed the control ration (p < 0.05). It can be concluded that growth performance is improved in animals fed diets containing 10% pumpkin and banana meal instead of corn, and tadpoles that received the avocado meal had the same performance as the conventional diets. Research should be carried out to assess other avenues for the replacement of ingredients in rations for bullfrog tadpoles.


O objetivo deste trabalho foi avaliar o desempenho e a metamorfose de girinos de rãtouro (Lithobates catesbeianus) alimentados com dietas balanceadas com farinha de banana, abacate e abóbora, todas feitas sem epicarpo, em substituição à farinha de milho. Utilizando um delineamento inteiramente casualizado, os animais foram colocados em tanques com capacidade de 30 litros em sistema de recirculação de água com densidade de 1 girino / L. Por meio de biometria quinzenal foram avaliados peso, comprimento padrão e total, quanto ao desenvolvimento metamórfico, ganho em peso, consumo, conversão alimentar, taxa de crescimento específico, sobrevivência, parâmetros físico-químicos da água e composição centesimal da carcaça (somente no final). Os resultados mostraram melhor desempenho para girinos alimentados com ração balanceada com farinha de abóbora e banana, seguidos daqueles alimentados com farelo de abacate e alimentados com ração controle (p <0,05). Os animais alimentados com as duas últimas rações não diferiram (p> 0,05). Pode-se concluir que houve melhor desempenho nos animais alimentados com dietas contendo 10% de abóbora e farelo de banana ao invés de milho, e aqueles que receberam farelo de abacate com o mesmo desempenho das dietas tradicionais. Pesquisas devem ser realizadas para avaliar outros níveis de reposição desses nutrientes por girinos de rã-touro.


Assuntos
Animais , Rana catesbeiana/crescimento & desenvolvimento , Cucurbita , Persea , Musa , Ração Animal/análise
15.
R. bras. Saúde Prod. Anim. ; 23: e2122312021, 2022. tab
Artigo em Inglês | VETINDEX | ID: vti-765898

RESUMO

The objective of this study was to evaluate the performance and metamorphosis of bullfrog tadpoles (Lithobates catesbeianus) fed balanced diets, wherein corn flour was replaced with banana, avocado, and pumpkin meal (all made without the epicarp). Using a completely randomized design, the animals were stored in tanks with a capacity of 30 L in a water recirculation system at a density of 1 tadpole/L. Through biweekly biometric measurements, the weight, standard, and total length were evaluated to determine metamorphic development, weight gain, consumption, feed conversion, specific growth rate, survival, physical-chemical parameters of water, and the percentage carcass composition (only at the end). Tadpoles fed rations balanced with pumpkin and banana flour performed the best, followed by those fed avocado meal and those fed the control ration (p < 0.05). It can be concluded that growth performance is improved in animals fed diets containing 10% pumpkin and banana meal instead of corn, and tadpoles that received the avocado meal had the same performance as the conventional diets. Research should be carried out to assess other avenues for the replacement of ingredients in rations for bullfrog tadpoles.(AU)


O objetivo deste trabalho foi avaliar o desempenho e a metamorfose de girinos de rãtouro (Lithobates catesbeianus) alimentados com dietas balanceadas com farinha de banana, abacate e abóbora, todas feitas sem epicarpo, em substituição à farinha de milho. Utilizando um delineamento inteiramente casualizado, os animais foram colocados em tanques com capacidade de 30 litros em sistema de recirculação de água com densidade de 1 girino / L. Por meio de biometria quinzenal foram avaliados peso, comprimento padrão e total, quanto ao desenvolvimento metamórfico, ganho em peso, consumo, conversão alimentar, taxa de crescimento específico, sobrevivência, parâmetros físico-químicos da água e composição centesimal da carcaça (somente no final). Os resultados mostraram melhor desempenho para girinos alimentados com ração balanceada com farinha de abóbora e banana, seguidos daqueles alimentados com farelo de abacate e alimentados com ração controle (p <0,05). Os animais alimentados com as duas últimas rações não diferiram (p> 0,05). Pode-se concluir que houve melhor desempenho nos animais alimentados com dietas contendo 10% de abóbora e farelo de banana ao invés de milho, e aqueles que receberam farelo de abacate com o mesmo desempenho das dietas tradicionais. Pesquisas devem ser realizadas para avaliar outros níveis de reposição desses nutrientes por girinos de rã-touro.(AU)


Assuntos
Animais , Rana catesbeiana/metabolismo , Larva/crescimento & desenvolvimento , Ração Animal
16.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1493925

RESUMO

ABSTRACT The objective of this study was to evaluate the performance and metamorphosis of bullfrog tadpoles (Lithobates catesbeianus) fed balanced diets, wherein corn flour was replaced with banana, avocado, and pumpkin meal (all made without the epicarp). Using a completely randomized design, the animals were stored in tanks with a capacity of 30 L in a water recirculation system at a density of 1 tadpole/L. Through biweekly biometric measurements, the weight, standard, and total length were evaluated to determine metamorphic development, weight gain, consumption, feed conversion, specific growth rate, survival, physical-chemical parameters of water, and the percentage carcass composition (only at the end). Tadpoles fed rations balanced with pumpkin and banana flour performed the best, followed by those fed avocado meal and those fed the control ration (p 0.05). It can be concluded that growth performance is improved in animals fed diets containing 10% pumpkin and banana meal instead of corn, and tadpoles that received the avocado meal had the same performance as the conventional diets. Research should be carried out to assess other avenues for the replacement of ingredients in rations for bullfrog tadpoles.


RESUMO O objetivo deste trabalho foi avaliar o desempenho e a metamorfose de girinos de rãtouro (Lithobates catesbeianus) alimentados com dietas balanceadas com farinha de banana, abacate e abóbora, todas feitas sem epicarpo, em substituição à farinha de milho. Utilizando um delineamento inteiramente casualizado, os animais foram colocados em tanques com capacidade de 30 litros em sistema de recirculação de água com densidade de 1 girino / L. Por meio de biometria quinzenal foram avaliados peso, comprimento padrão e total, quanto ao desenvolvimento metamórfico, ganho em peso, consumo, conversão alimentar, taxa de crescimento específico, sobrevivência, parâmetros físico-químicos da água e composição centesimal da carcaça (somente no final). Os resultados mostraram melhor desempenho para girinos alimentados com ração balanceada com farinha de abóbora e banana, seguidos daqueles alimentados com farelo de abacate e alimentados com ração controle (p 0,05). Os animais alimentados com as duas últimas rações não diferiram (p> 0,05). Pode-se concluir que houve melhor desempenho nos animais alimentados com dietas contendo 10% de abóbora e farelo de banana ao invés de milho, e aqueles que receberam farelo de abacate com o mesmo desempenho das dietas tradicionais. Pesquisas devem ser realizadas para avaliar outros níveis de reposição desses nutrientes por girinos de rã-touro.

17.
An Acad Bras Cienc ; 93(suppl 4): e20210270, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730623

RESUMO

Two experiments were carried out to test better stocking proportion according to animal size for tilapia (Oreochromis niloticus) and tadpole (Lithobates catesbeianus). The experiments were laid out in a completely randomized design with five treatments (in Experiment I) and four treatments (in Experiment II). In Experiment I, the treatments consisted of a tilapia monoculture; a 75% tilapia + 25% tadpole polyculture; a 50% tilapia + 50% tadpole; a 25% tilapia + 75% tadpole; and a tadpole monoculture. In Experiment II, the treatments were represented by a tilapia monoculture; a 12.5% tilapia + 87.5% tadpole polyculture; a 25% tilapia + 75% tadpole; and a tadpole monoculture. In the first trial, mortality rate differed significantly, with the polyculture treatments having almost 100% mortality of tadpoles. In the second experiment, after adjustments in the initial size of the species, there were significant differences between treatments, with the 12.5% tilapia + 87.5% tadpole polyculture and the tadpole monoculture providing the best results. Regardless of the chosen density, for a polyculture of Nile tilapia and bullfrog tadpoles, ideal conditions would be stocking tilapia fry weighing 50% of the weight initial tadpoles and the proportion of one tilapia for seven tadpoles.


Assuntos
Ciclídeos , Tilápia , Animais , Larva , Rana catesbeiana
18.
Parkinsonism Relat Disord ; 93: 62-65, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34808519

RESUMO

INTRODUCTION: Transcranial direct current stimulation (tDCS) improves postural response to perturbation in patients with Parkinson's disease (PwPD). However, the influence of baseline characteristics such as clinical/cognitive and postural performance on the response to tDCS remains unclear. OBJECTIVE: To investigate whether baseline level of postural control (performance during sham condition) and clinical/cognitive characteristics are associated with tDCS-related changes in postural responses to external perturbations in PwPD. METHODS: Twenty-four PwPD participated in this study. Clinical assessment included disease severity, disease duration, levodopa equivalent dose and global cognition. Anodal tDCS protocols targeting the primary motor cortex were applied in two separate sessions (at least 2 weeks apart): active (2 mA for 20 min) and sham stimulation. Seven trials with the backward translation of the support base (20 cm/s and 5 cm) were performed after tDCS. Postural outcomes included the recovery time to stable position and onset latency of the medial gastrocnemius (MG). Pearson and Spearman correlation tests were performed. RESULTS: No significant correlations were observed between clinical/cognitive characteristics and tDCS-related changes in postural responses. Negative associations were observed between the baseline level of postural control and tDCS-related changes in postural responses for the recovery time (r = -0.657; p < 0.001) and the MG onset latency (rs = -0.539; p = 0.007). PwPD with worse baseline postural control demonstrated greater improvement after active stimulation. CONCLUSIONS: Findings suggest that tDCS-related effects on postural response to perturbation are related to the baseline level of postural control, but not to clinical characteristics in PwPD. Those with worse baseline postural control responded better to tDCS.


Assuntos
Eletromiografia/estatística & dados numéricos , Doença de Parkinson/cirurgia , Equilíbrio Postural , Estimulação Transcraniana por Corrente Contínua/estatística & dados numéricos , Idoso , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Período Pré-Operatório , Resultado do Tratamento
19.
Front Chem ; 9: 729787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490211

RESUMO

1,2:3,5-Di-O-isopropylidene-α-D-xylofuranose (DX) is a major component of a new bio-crude: a viscous oil presenting petroleum-friendly properties produced by the ketalization of sugarcane bagasse. This article studies DX HDO (hydrodeoxygenation) over a Pd/HBEA catalyst in a batch reactor at 250°C. The effects of hydrogen pressure from 10 to 40 bar, catalyst/DX ratio from ½ to 2, and reaction time 0-24 h were investigated. A range of conditions for complete hydrodeoxygenated DX into alkanes with a Pd/HBEA catalyst was found. In these conditions, a low coke yield with water as the principal deoxygenated product was obtained. Further, higher amounts of alkanes containing seven or more carbons (A7+) were favored at 30 bar of hydrogen pressure, Cat/DX ratio = 2, and short reaction time. Products analysis that accompanied the above variations during reaction time led to general insights into reaction pathways. First, in the presence of DX, an effective n-hexane conversion was not observed on experiments of low catalyst/DX ratio (½) or in the initial period of high Cat/DX ratio, suggesting DX is much more successful than n-hexane to compete for active sites. Then, the formation of a pool of oxygenated compounds, such as furans, ketones, and carboxylic acids, along with lighter and heavier alkanes was observed. Hence, the aforementioned oxygenates may undergo reactions, such as aldol condensation with subsequent hydrodeoxygenation reaction, generating heavier alkanes.

20.
B. Inst. Pesca ; 47: e676, 2021. tab
Artigo em Inglês | VETINDEX | ID: vti-765378

RESUMO

The present study evaluated the influence of thermal management during the larviculture of Betta splendens on survival and sex ratio, aiming to increase the proportion of males. Newly hatched larvae were subjected to different thermal regimes, namely, T25, T28, T30 and T33 (25, 28, 30 and 33°C, respectively). The experiment was laid out in a completely randomized design, with 4 treatments and 10 repetitions. Thermal treatment was maintained until 15 days post-hatch (DPH). Mortality was determined at the end of the thermal regime and again at 45 DPH. At the end of the experiment, the number of males and females obtained in the different thermal treatments was counted to analyze the obtained sex ratio. There was a significant effect on mortality as a function of temperature only at 15 DPH (p <0.001), with the lowest values recorded in treatments T25, T28 and T30. In terms of sex ratio, up to 65% of males were obtained in treatment T33 (p = 0.037). In conclusion, thermal management during the larval period can be a strategy to increase the proportion of males, but the increase in mortality due to the rise in temperature should be considered.(AU)


O presente estudo avaliou a influência da manipulação térmica durante a larvicultura de Betta splendens na sobrevivência e razão sexual, buscando aumento na proporção de machos. Larvas recém-eclodidas foram submetidas a diferentes regimes térmicos, denominados: T25, T28, T30 e T33 (25, 28, 30 e 33°C, respectivamente). Seguiu-se um delineamento inteiramente casualizado, com 4 tratamentos e 10 repetições. O tratamento termal foi mantido até os 15 DPE (dias pós-eclosão). No encerramento do regime termal e novamente aos 45 DPE foi contabilizada a mortalidade. No final do experimento foi contabilizado o número de machos e fêmeas obtidos nos diferentes tratamentos térmicos para análise da proporção sexual obtida. Houve efeito significativo da mortalidade em função da temperatura apenas aos 15 DPE (p <0,001) e os tratamentos T25, T28 e T30 apresentaram os menores valores para tal parâmetro. Para a razão sexual, foram obtidos até 65% de machos no tratamento T33 (p = 0,037). Conclui-se que a manipulação termal durante o período larval pode ser uma estratégia para o aumento da proporção de machos, considerando o aumento da mortalidade em função da elevação da temperatura.(AU)


Assuntos
Animais , Pesqueiros , Comportamento Sexual Animal , Razão de Masculinidade
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