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1.
Eur J Prosthodont Restor Dent ; 32(2): 194-202, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38299347

RESUMEN

To evaluate the effect of calcium hydroxide (CH), sodium ascorbate (SA) and sodium thiosulfate (ST) filling the pulp chamber on color stability and longevity of teeth after internal bleaching. Crowns of bovine incisors were submitted to internal bleaching and divided into groups according the material used in the pulp chamber: Control, CH, SA, ST. Each group was divided into two subgroups according to the time to perform restorative procedures (7 or 15 days). Color measurement was performed with a spectrophotometer at nine periods. The darkening (ΔE) values were calculated. The Mann-Whitney test was used to statistically analyze the data (p ⟨ 0.05). After bleaching, ΔE values were higher than 3.5, showing that the procedure was effective. After 24 hours, no difference was observed between groups. After 7 days, SA showed higher ΔE than the control group (p ⟨ 0.05). CH and TS did not differ from the control group. In restorations performed after 7/15 days, SA group showed higher values of darkening after 1 and 4 months than the control group (p ⟨ 0.05). SA induced perceptible darkening after bleaching and should not be used to fill the pulp chamber. ST and CH show color stability and longevity after 12 months.


Asunto(s)
Antioxidantes , Hidróxido de Calcio , Cavidad Pulpar , Blanqueadores Dentales , Blanqueamiento de Dientes , Animales , Bovinos , Antioxidantes/farmacología , Blanqueadores Dentales/farmacología , Espectrofotometría , Ácido Ascórbico/farmacología , Tiosulfatos/farmacología , Decoloración de Dientes , Color
2.
Mar Environ Res ; 183: 105806, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36459755

RESUMEN

Coastal marine ecosystems have structural and functional features usually connected by the seasonal transfer of nutrients and organisms. These environments can utilize inter-ecosystem subsidies to increase resilience and maturity and support human activities like fishing. However, the importance of the connection and the role of the seasonal pulse of energy flows to enhance maturity are still poorly understood and reported. Our objective in this paper is to assess the effect of seasonal hydrological pulses on two tropical coastal interconnected ecosystems. Thus, we made four Ecopath models for estuarine and neritic environments considering the dry and rainy seasons, with a similar sampling design that allowed them to be compared. Our results provide evidence for the occurrence of the pulsed ecosystems since both environments seem driven by the river flow. Estuary presents more and more substantial differences (measured by ecosystem attributes) in both seasons because it is directly affected by river floods than the neritic environment. The neritic is affected indirectly by the movement of species from the estuary and by a weaker river flow. In the dry season, the differences between ecosystems are lower because the dry season trend to homogenize cycling, maturity, homeostasis, and resilience. We found that the seasonal river flow (pulse) forces the variability of biomass, flows, and ecosystem features, and this variance creates the required stability for both ecosystems. Still, these environments benefit through the exchange of components that relieve the pressures of predation on specific groups and maintain the energy flow necessary for the functioning of their trophic webs. The pulse by the rainfall favors connectivity and equalizes the two systems, increasing the connectivity between them and the exchange of subsidies that strengthens the trophic structures, contributing to the increase in maturity. In these ecosystems, seasonal changes become a key factor for exchanging flows that will promote sustainability, the accumulation of more biomass (growth), and the optimization of reserve energy (development) in both systems. This efficient joint strategy of perpetuation is what promotes resistance and resilience to these ecosystems, which together can reach different states of equilibrium, translated into maturity to withstand new environmental changes.


Asunto(s)
Ecosistema , Ríos , Humanos , Biomasa , Estuarios , Estaciones del Año
3.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1422-1430, Nov.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355676

RESUMEN

This work was conducted to evaluate the effect of deferred pasture condition of Brachiaria brizantha cv. Marandu in the late winter on tillering during the growing season. The treatments were three pasture conditions at late winter: short pasture, tall pasture and tall/mown pasture. In September and October, tiller appearance rate (TApR) and tiller mortality rate (TMoR) were greater in the tall/mown pasture. In November and December, tall pasture presented greater TApR. From November to January the TMoR was greater in the tall pasture. The tiller stability index of short and tall/mown pastures were greater in October. The short pasture presented a greater tiller number than the tall and tall/mown pastures during the entire experimental period. Deferred and short pasture of marandu palisade grass at late winter presents in general lower tiller mortality and higher population density of tillers from the early spring onwards, in comparison to tall pasture. The mowing of marandu palisade grass with high forage mass at the late winter, although it only temporarily compromises the population stability of tillers, also stimulates its fast tillering from spring on.(AU)


Este trabalho foi conduzido com o objetivo de avaliar o efeito da condição da pastagem diferida de Brachiaria brizantha cv. Marandu ao final do inverno sobre o perfilhamento durante a estação de crescimento. Os tratamentos foram três condições de pastagem no final do inverno: pasto baixo, pasto alto e pasto alto/roçado. Nos meses de setembro e outubro, a taxa de aparecimento de perfilhos (TApP) e a taxa de mortalidade de perfilhos (TMoP) foram maiores na pastagem alta/roçada. Nos meses de novembro e dezembro, a pastagem alta apresentou maior TApP. De novembro a janeiro, a TMoP foi maior na pastagem alta. Os índices de estabilidade de perfilhos das pastagens baixas e altas/roçadas foram maiores em outubro. A pastagem baixa apresentou maior número de perfilhos do que as pastagens altas e altas/roçadas durante todo o período experimental. A pastagem diferida e baixa de capim-marandu no final do inverno apresenta, em geral, menor mortalidade de perfilhos e maior densidade populacional de perfilhos no início da primavera, em comparação com a pastagem alta. A roçada do capim-marandu com alta massa de forragem ao final do inverno, embora comprometa apenas temporariamente a estabilidade populacional dos perfilhos, também estimula o perfilhamento rápido a partir da primavera.(AU)


Asunto(s)
Estaciones del Año , Pastizales/análisis , Brachiaria/crecimiento & desarrollo
4.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1413-1421, Nov.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355684

RESUMEN

The objective this study was to identify differences in the morphogenic patterns of four Urochloa brizantha cultivars (marandu, piatã, xaraés and paiaguás grasses) during the stockpiling period. A completely randomized design was used, with three replications, in experimental plots of 9m². The evaluations took place over 2 years. The grasses were stockpiled for 92 (Year 1) and 95 (Year 2) days. The leaf appearance rate of paiaguás grass was higher, compared to other grasses. In Year 1, the stem elongation rate of xaraés grass was higher than other grasses. At the end of stockpiling period of Year 1, the tiller population density (TPD) was higher in the paiaguás grass, intermediate in the xaraés and marandu grasses and lower in the piatã grass. At the end of the stockpiling period in Year 2, TPD was higher in the paiaguás grass canopy, intermediate in the marandu and piatã grasses canopies, and lower in the xaraés grass canopy. Paiaguás grass has greater leaf growth during the stockpiling period and is therefore suitable for use under stockpiled grazing. Xaraés grass has high stem elongation during the stockpiling period, which is why its use under stockpiled grazing must be accompanied by adjustments in pasture management.(AU)


O objetivo deste estudo foi identificar diferenças nos padrões morfogênicos de quatro cultivares de Urochloa brizantha (marandu, piatã, xaraés e paiaguás) durante o período de diferimento. Foi utilizado o delineamento inteiramente ao acaso, com três repetições, em parcelas experimentais de 9m². As avaliações ocorreram por dois anos. Os capins foram diferidos por 92 (Ano 1) e 95 (Ano 2) dias. A taxa de aparecimento foliar do capim-paiaguás foi maior, em comparação aos demais capins. No Ano 1, a taxa de alongamento do colmo do capim-xaraés foi superior aos demais capins. No final do diferimento do Ano 1, a densidade populacional de perfilho (DPP) foi maior no capim-paiaguás, intermediária nos capins xaraés e marandu e inferior no capim-piatã. No fim do período de diferimento do Ano 2, a DPP foi superior no dossel de capim-paiaguás, intermediária nos dosséis dos capins marandu e piatã, e menor no dossel de capim-xaraés. O capim-paiaguás tem maior crescimento foliar durante o período de diferimento, sendo, portanto, apropriado para uso sob pastejo diferido. O capim-xaraés apresenta elevado alongamento de colmo durante o período de diferimento, razão pela qual seu uso sob pastejo diferido deve vir acompanhado de ajustes no manejo da pastagem.(AU)


Asunto(s)
Tallos de la Planta , Brachiaria/crecimiento & desarrollo , Morfogénesis/fisiología
5.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1403-1412, Nov.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355685

RESUMEN

The objective was to identify lowering strategies for Urochloa brizantha cv. Marandu in the beginning of the stockpiling period that increase forage production and improve the structure of stockpiled canopies. Three lowering strategies were evaluated: maintenance of marandu palisade grass with 15cm four months before the stockpiling period; maintenance of palisade grass with 30cm for four months, and lowering to 15cm before the stockpiling period; and maintaining of palisade grass at 45cm for four months, and lowering to 15cm before the stockpiling period. The experimental design was completely randomized, with four replications. At the end of stockpiling, the number of reproductive tillers and forage mass were higher in the canopy under 15/15cm than in the others; the percentage of live leaf was higher in the canopy under 45/15cm than under 15/15cm. Forage production during the stockpiling period was higher in the canopy under 15/15cm and lower in the under 45/15cm. Maintaining 15cm marandu palisadegrass for four months before the stockpiling period increases forage production during this period. The lowering of the marandu palisadegrass from 45 to 15cm at the beginning of the stockpiling period improves the structure of the stockpiled canopy.(AU)


Objetivou-se identificar estratégias de rebaixamento da Urochloa brizantha cv. Marandu no início do diferimento, as quais resultem em aumento da produção e em melhoria da estrutura do dossel diferido. Foram avaliadas três estratégias de rebaixamento no início do diferimento: manutenção do capim-marandu com 15cm por quatro meses antes do início do diferimento; manutenção do capim-marandu com 30cm por quatro mese, e rebaixamento para 15cm no início do diferimento; e manutenção do capim com 45cm por quatro meses e rebaixamento para 15cm no início do diferimento. O delineamento foi inteiramente ao acaso, com quatro repetições. No fim do diferimento, o número de perfilho reprodutivo e a massa de forragem foram superiores no dossel sob 15/15cm do que nos demais; a percentagem de folha viva foi maior no dossel sob 45/15cm do que sob 15/15cm. A produção de forragem durante o diferimento foi superior no dossel sob 15/15cm e inferior no sob 45/15cm. A manutenção do capim-marandu com 15cm por quatro meses antes do período de diferimento aumenta a produção de forragem neste período. O rebaixamento do capim-marandu de 45 para 15cm no início do diferimento melhora a estrutura do dossel diferido.(AU)


Asunto(s)
Producción de Cultivos , Hojas de la Planta/anatomía & histología , Brachiaria/crecimiento & desarrollo
6.
Braz J Med Biol Res ; 54(8): e11447, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34320123

RESUMEN

Knowledge about the needs of psychiatric patients is essential for mental health care planning. However, research on met and unmet needs is still scarce, particularly in low- and middle-income countries. This study aimed to describe the patients' needs (met and unmet) at least four years after their first psychiatric hospitalization and to verify the role of demographic and clinical features as possible predictors of these needs. Patients who had their first psychiatric admission between January 1, 2006 and December 31, 2007 at an inpatient unit in the city of Ribeirão Preto, Brazil, were eligible to participate in the study. Patients were contacted and face-to-face interviews were conducted by psychologists using the Camberwell Assessment of Need. Data were analyzed using zero-inflated negative binomial regression model. Of 933 eligible patients, 333 were interviewed. The highest level of needs was related to welfare benefits (32.4%, unmet=25.5%), followed by household skills (30.3%, unmet=3.0%), psychotic symptoms (29.4%, unmet=9.0%), psychological distress (27.6%, unmet=8.4%), physical health (24.3%, unmet=5.4%), daytime activities (19.5%, unmet=16.5%), and money (16.8%, unmet=9.0%). Fewer years of schooling, living with relatives, and unemployment at the moment of the first admission were significantly associated with a higher number of both met and unmet needs in the follow-up. Unmet needs were also more often reported by patients living alone. In conclusion, socioeconomic indicators were the best predictors of needs. The unmet needs related to welfare benefits point to the need for specific social and health policies.


Asunto(s)
Hospitalización , Pacientes Internos , Brasil , Estudios de Cohortes , Humanos , Evaluación de Necesidades
7.
Sci Rep ; 11(1): 11847, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-34088923

RESUMEN

Acoustical geographic variation is common in widely distributed species and it is already described for several taxa, at various scales. In cetaceans, intraspecific variation in acoustic repertoires has been linked to ecological factors, geographical barriers, and social processes. For the common bottlenose dolphin (Tursiops truncatus), studies on acoustic variability are scarce, focus on a single signal type-whistles and on the influence of environmental variables. Here, we analyze the acoustic emissions of nine bottlenose dolphin populations across the Atlantic Ocean and the Mediterranean Sea, and identify common signal types and acoustic variants to assess repertoires' (dis)similarity. Overall, these dolphins present a rich acoustic repertoire, with 24 distinct signal sub-types including: whistles, burst-pulsed sounds, brays and bangs. Acoustic divergence was observed only in social signals, suggesting the relevance of cultural transmission in geographic variation. The repertoire dissimilarity values were remarkably low (from 0.08 to 0.4) and do not reflect the geographic distances among populations. Our findings suggest that acoustic ecology may play an important role in the occurrence of intraspecific variability, as proposed by the 'environmental adaptation hypothesis'. Further work may clarify the boundaries between neighboring populations, and shed light into vocal learning and cultural transmission in bottlenose dolphin societies.


Asunto(s)
Acústica , Delfín Mular/fisiología , Sonido , Vocalización Animal/fisiología , Animales , Océano Atlántico , Conducta Animal , Biodiversidad , Ecología , Geografía , Mar Mediterráneo , Espectrografía del Sonido
8.
Braz. j. med. biol. res ; 54(8): e11447, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1285673

RESUMEN

Knowledge about the needs of psychiatric patients is essential for mental health care planning. However, research on met and unmet needs is still scarce, particularly in low- and middle-income countries. This study aimed to describe the patients' needs (met and unmet) at least four years after their first psychiatric hospitalization and to verify the role of demographic and clinical features as possible predictors of these needs. Patients who had their first psychiatric admission between January 1, 2006 and December 31, 2007 at an inpatient unit in the city of Ribeirão Preto, Brazil, were eligible to participate in the study. Patients were contacted and face-to-face interviews were conducted by psychologists using the Camberwell Assessment of Need. Data were analyzed using zero-inflated negative binomial regression model. Of 933 eligible patients, 333 were interviewed. The highest level of needs was related to welfare benefits (32.4%, unmet=25.5%), followed by household skills (30.3%, unmet=3.0%), psychotic symptoms (29.4%, unmet=9.0%), psychological distress (27.6%, unmet=8.4%), physical health (24.3%, unmet=5.4%), daytime activities (19.5%, unmet=16.5%), and money (16.8%, unmet=9.0%). Fewer years of schooling, living with relatives, and unemployment at the moment of the first admission were significantly associated with a higher number of both met and unmet needs in the follow-up. Unmet needs were also more often reported by patients living alone. In conclusion, socioeconomic indicators were the best predictors of needs. The unmet needs related to welfare benefits point to the need for specific social and health policies.


Asunto(s)
Humanos , Hospitalización , Pacientes Internos , Brasil , Estudios de Cohortes , Evaluación de Necesidades
9.
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2339-2347, Nov.-Dec. 2020. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1142298

RESUMEN

Objetivou-se avaliar as características estruturais e a produção de forragem do capim-piatã submetido à combinação de duas frequências de corte (95% e máxima interceptação de luz pelo dossel forrageiro, ILmax) e duas alturas pós-corte (15 e 20cm), no período de janeiro de 2012 a março de 2013. O delineamento utilizado foi em blocos ao acaso, com três repetições, em esquema fatorial 2x2, totalizando 12 unidades experimentais de 14m2 cada. Foram avaliadas as seguintes variáveis-respostas: altura do dossel no pré-corte, intervalo de corte, índice de área foliar pré e pós-corte, taxa de produção de forragem e as percentagens de colmo, folha e forragem morta na forragem produzida. A altura pré-corte decresceu durante o experimento (de 65,81 para 34,03cm), sendo a menor altura observada no dossel sob alta frequência de desfolhação (95% de IL). A taxa de produção de forragem foi maior nas épocas favoráveis ao crescimento da gramínea forrageira. As percentagens de folha, colmo e forragem morta foram semelhantes entre as frequências de corte. Assim, o capim-piatã sob manejo de desfolhação intermitente pode ser colhido com qualquer combinação de frequências de corte de 95% e ou máxima interceptação de luz, e alturas pós-corte de 15 ou 20cm.(AU)


The objective of this study was to evaluate the structural characteristics and forage production of the piatã grass submitted to the combination of two cutting frequencies (95% and maximum interception of light by the forage canopy, ILmax) and two post cutting heights (15 and 20cm) in the period from January 2012 to March 2013. The design was a randomized complete block with three replications, in a 2x2 factorial scheme, totaling 12 experimental units of 14m2 each. The following variables were evaluated: pre-cut canopy height, cut interval, pre and post-cut leaf area index, forage yield rate, and percentage of stem, leaf and dead forage in the forage produced. The pre-cut height decreased during the experiment (from 65.81 to 34.03cm), with the lowest height observed in the canopy under high frequency of defoliation (95% IL). The rate of forage production was higher in the seasons favorable to forage grass growth. The percentages of leaf, stem and dead fodder were similar between cut-off frequencies. Thus, piatã grass under intermittent defoliation management can be harvested with any combination of 95% and maximum light interception cut frequencies, and post cutting heights of 15 or 20cm.(AU)


Asunto(s)
Producción de Cultivos , Brachiaria/anatomía & histología , Brachiaria/crecimiento & desarrollo
10.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32792287

RESUMEN

INTRODUCTION: The in vitro creation of hyaline joint cartilage is a challenge since, to date, the ex vivo synthesis of a structured tissue with the same biomechanical and histological properties of the joint cartilage has not been achieved. To simulate the physiological conditions we have designed an in vitro culture system that reproduces joint movement. MATERIAL AND METHOD: We have developed a cell culture bioreactor that prints a mechanical stimulus on an elastin matrix, in which mesenchymal stem cells (MSC) are embedded. The first phase of study corresponds to the development of a bioreactor for hyaline cartilage culture and the verification of cell viability in the elastin matrix in the absence of stimulus. The second phase of the study includes the MSC culture under mechanical stimulus and the analysis of the resulting tissue. RESULTS: After culture under mechanical stimulation we did not obtain hyaline tissue due to lack of cellularity and matrix destructuring. CONCLUSION: The stimulus pattern used has not been effective in generating hyaline cartilage, so other combinations should be explored in future research.


Asunto(s)
Reactores Biológicos , Condrocitos/citología , Elastina , Cartílago Hialino , Células Madre Mesenquimatosas/citología , Técnicas de Cultivo de Tejidos , Fenómenos Biomecánicos , Cartílago Articular , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Supervivencia Celular , Condrocitos/fisiología , Medios de Cultivo , Matriz Extracelular , Humanos , Cartílago Hialino/fisiología , Células Madre Mesenquimatosas/fisiología , Resultados Negativos , Presión , Impresión Tridimensional
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