Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros










Intervalo de año de publicación
1.
RSC Adv ; 14(10): 6883-6895, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38410360

RESUMEN

Herein, Ni2+-Cu2+ co-doped barium hexaferrites (BaFe11Cu1-xNixO19, 0.0 ≤ x≤ 1.0 with an interval of 0.25) were successfully synthesized using a co-precipitation method. The formation of a magnetoplumbite structure with the P63/mmc space group was confirmed by Rietveld refinement of the obtained X-ray diffraction patterns. Microstructural investigations revealed grains in the shape of hexagonal plates, while co-doping resulted in a variation in the grain sizes of the prepared samples. X-ray photoelectron spectroscopy was performed to determine the valence state of iron in the prepared hexaferrites. Impedance spectroscopy analysis revealed that dielectric permittivity initially decreased with an increase in the co-dopant content up to x = 0.5 and then increased by two orders of magnitude for x = 1.0. Alternatively, resistive properties showed microstructural resistance values in the range 105-108 Ω, with the highest value obtained for the sample with x = 0.5. Furthermore, magnetic measurements indicated that all the prepared samples exhibited ferrimagnetic behaviour. Saturation magnetization and magnetic anisotropy values were found to be the highest for the sample with x = 1.0, which also had the lowest coercivity among the prepared samples. Herein, the observed variations in the obtained results can be explained by the variations in grain sizes and the Fe2+/Fe3+ ratio associated with the preferential occupation of co-dopants at octahedral sites. Based on our findings, the BaFe11Ni1O19 (x = 1.0) composition appears to be the most promising choice as a microwave absorption material among the prepared samples owing to the coexistence of high dielectric permittivity (>103 at 107 Hz) and saturation magnetization (73 emu g-1).

2.
RSC Adv ; 12(20): 12344-12354, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35480359

RESUMEN

Magnetite (Fe3O4) nanoparticles were successfully prepared by a co-precipitation method. Rietveld refinement on the X-ray diffraction pattern confirmed the development of a single-phase cubic spinel structure with space group Fd3̄m. However, 57Fe Mössbauer spectroscopy suggested the presence of Fe3+ and Fe2.5+ (mixed Fe3+ and Fe2+) ions at the tetrahedral and octahedral sites of the inverse spinel structure, respectively. Impedance spectroscopy measurements showed a discontinues variation in the temperature dependence of the sample's resistive behavior, indicating the appearance of semiconductor-metal-semiconductor like transitions between the temperature range of 293 and 373 K. A similar dual transition was also observed from the dielectric and conductivity measurements around the same temperature regions. The observed unusual transition is explained in term of the competitive effects among the hopping of localized/delocalized and short-range/long-range charge carriers present in the sample. Moreover, the prepared sample exhibits colossal dielectric permittivity (∼106), reduced tangent loss (∼0.2) and moderate conductivity (>10-6 S cm-1) values, making Fe3O4 nanoparticles a potential candidate for electromagnetic absorbing materials.

3.
Braz. j. biol ; 82: e238665, 2022. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1153463

RESUMEN

Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vector's behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.


A região de Malakand é uma área endêmica para leishmaniose cutânea (CL). No entanto, há um número limitado de estudos sobre esta doença no Paquistão. Portanto, foi realizado um estudo para entender o nível de atitude e prática de conscientização entre os residentes de Makaland em relação aos CL e os vetores da doença. Este estudo adotou uma abordagem transversal com um total de 400 entrevistados (n = 93 rural e n = 307 urbano). No geral, a população da região de Malakand (61,2%) estava bem informada sobre o papel da mosca na transmissão de doenças, mas a maioria não possui conhecimento sobre o comportamento do vetor e quase um quarto (24,5%) foi incapaz de fornecer conhecimento sobre medidas de controle adequadas . De maneira alarmante, a prática e as atitudes da população em geral não foram satisfatórias, pois cerca da metade (49,8%) da população adotou algum método de controle. Este estudo apela ao aumento da conscientização por meio de campanhas de educação em saúde para reduzir o risco de surtos de leishmaniose cutânea no futuro.


Asunto(s)
Humanos , Animales , Psychodidae , Leishmaniasis Cutánea/epidemiología , Pakistán/epidemiología , Población Rural , Población Urbana , Conocimientos, Actitudes y Práctica en Salud , Estudios Transversales
4.
Braz. j. biol ; 82: 1-6, 2022. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468440

RESUMEN

Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vector's behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.


A região de Malakand é uma área endêmica para leishmaniose cutânea (CL). No entanto, há um número limitado de estudos sobre esta doença no Paquistão. Portanto, foi realizado um estudo para entender o nível de atitude e prática de conscientização entre os residentes de Makaland em relação aos CL e os vetores da doença. Este estudo adotou uma abordagem transversal com um total de 400 entrevistados (n = 93 rural e n = 307 urbano). No geral, a população da região de Malakand (61,2%) estava bem informada sobre o papel da mosca na transmissão de doenças, mas a maioria não possui conhecimento sobre o comportamento do vetor e quase um quarto (24,5%) foi incapaz de fornecer conhecimento sobre medidas de controle adequadas . De maneira alarmante, a prática e as atitudes da população em geral não foram satisfatórias, pois cerca da metade (49,8%) da população adotou algum método de controle. Este estudo apela ao aumento da conscientização por meio de campanhas de educação em saúde para reduzir o risco de surtos de leishmaniose cutânea no futuro.


Asunto(s)
Humanos , Animales , Control de Mosquitos/normas , Leishmaniasis Cutánea/prevención & control , Leishmaniasis Cutánea/transmisión , Mosquitos Vectores/parasitología , Psychodidae/parasitología , Enfermedades Desatendidas/prevención & control
5.
Braz. j. biol ; 822022.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468627

RESUMEN

Abstract Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vectors behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.


Resumo A região de Malakand é uma área endêmica para leishmaniose cutânea (CL). No entanto, há um número limitado de estudos sobre esta doença no Paquistão. Portanto, foi realizado um estudo para entender o nível de atitude e prática de conscientização entre os residentes de Makaland em relação aos CL e os vetores da doença. Este estudo adotou uma abordagem transversal com um total de 400 entrevistados (n = 93 rural e n = 307 urbano). No geral, a população da região de Malakand (61,2%) estava bem informada sobre o papel da mosca na transmissão de doenças, mas a maioria não possui conhecimento sobre o comportamento do vetor e quase um quarto (24,5%) foi incapaz de fornecer conhecimento sobre medidas de controle adequadas . De maneira alarmante, a prática e as atitudes da população em geral não foram satisfatórias, pois cerca da metade (49,8%) da população adotou algum método de controle. Este estudo apela ao aumento da conscientização por meio de campanhas de educação em saúde para reduzir o risco de surtos de leishmaniose cutânea no futuro.

6.
Braz J Biol ; 82: e238665, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33825759

RESUMEN

Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vector's behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.


Asunto(s)
Leishmaniasis Cutánea , Psychodidae , Animales , Estudios Transversales , Conocimientos, Actitudes y Práctica en Salud , Humanos , Leishmaniasis Cutánea/epidemiología , Pakistán/epidemiología , Población Rural , Población Urbana
7.
Saudi J Biol Sci ; 28(3): 1944-1953, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33732080

RESUMEN

Several anti-nutritional substances are found in plant derivatives for example phytate, that make the nutrients and minerals unavailable to fish, hence leading to poor growth performance. Presence of the anti-nutrient factor such as phytate is a chelated compound and need enzyme for its breakdown and availability of nutrients to improve fish growth. This research work was performed to check the improvement of overall performance of Cyprinus carpio fingerlings by the help of phytase addition in Moringa oleifera by- products based diet. Combination of Moringa seed meal and Moringa leaf meal was utilized as test ingredient to formulate seven test feeds, containing graded levels of phytase (0, 500, 650, 800, 950, 1100 and 1250 FTU kg-1). In feeding trial of 70 days, fingerlings were given feed two times in a day at the rate of 4% of wet weight of their bodies and faeces were collected. According to current results, it was found that growth performance parameters i.e. weight gain; 25 g, specific growth rate; 1.67 and feed conversion ratio; 1.10 were improved to maximum at 950 FTU kg-1. Digestibility of nutrients (crude protein; 73%, crude fat; 71% and gross energy; 67%) and minerals absorption was also maximum (Ca; 70%, Zn; 66%, K; 74%, Mn; 66% and P; 71%) at 950 FTU kg-1. Lowest growth efficiency, nutrient digestibility and mineral absorption were observed in fingerlings fed at control diet (0 FTU kg-1). Results of the current study, proved that 950 FTU kg-1 is the most optimum level of phytase to formulate economical and ecofriendly feed for improved growth of C. carpio fingerlings as it decreases the discharge of minerals and nutrients in water bodies.

8.
Braz J Biol ; 82: e238665, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33787717

RESUMEN

Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vector's behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.


Asunto(s)
Leishmaniasis Cutánea , Psychodidae , Animales , Estudios Transversales , Conocimientos, Actitudes y Práctica en Salud , Humanos , Leishmaniasis Cutánea/epidemiología , Pakistán/epidemiología , Población Rural , Población Urbana
9.
Mymensingh Med J ; 26(4): 812-820, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29208869

RESUMEN

Accurate prediction of the space available to accommodate the size of the un-erupted canines and premolars plays an important role in mixed dentition in Orthodontics. This Descriptive cross sectional study was carried out in the Department of Orthodontics of Bangabandhu Sheikh Mujib Medical University from July 2014 to June 2015. Dental study models of 140 patients were taken as sample. The sample was consisted of 54 Bangladeshi males and 86 females aged between 12 to 17 years and without any previous orthodontic treatment fully erupted permanent teeth and with no dental anomalies were recruited. The study was done by measuring the mesio-distal dimensions of teeth over the dental cast. A pre-structured data collection form which includes the particulars of the patient and data was filled. All patients were having a serial number to maintain their confidentiality. The study protocol was approved by "Institutional Review Board" of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh. Un-paired t test were used to examine differences between genders, correlation coefficients and linear regression equations were used to carry out the analysis. Descriptive statistics including means, standard deviations, and minimum-maximum values were calculated. Unpaired sample 't' tests were carried out to compare tooth size between the sexes. Logistic regression for development of new prediction formula on the basis of study sample of our population. Pearson correlation coefficient test for found the correlation between mandibular incisors and mandibular and maxillary canine and premolars in each quadrant. The difference between the present study with that of Moyers and Tanaka and Johnston were statistically significant (p<0.001). The values from Moyers and Tanaka and Johnston methods exceed while comparing to Bangladeshi population. Therefore, Moyers and Tanaka and Johnston method of prediction are not applicable for our population.


Asunto(s)
Dentición Mixta , Adolescente , Bangladesh , Diente Premolar , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Odontometría
10.
Cryo Letters ; 33(1): 12-23, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22434118

RESUMEN

A vitrification procedure using aluminium cryo-plates (V-Cryo-plate procedure) was successfully developed and adjusted for in vitro-grown mint (Mentha spp.) shoot tips. Shoots were cultured at 25°C on MS medium containing 0.088 M sucrose for 7 to 14 days after the last subculture. Shoot tips with a basal part (1-1.5 mm × 1 mm) were dissected from the shoots and precultured at 25°C for 1 day on the same medium. Precultured shoot tips were placed on aluminium cryo-plates with 10 wells and embedded in alginate gel. Osmoprotection was performed by immersing the cryo-plates for 30 min at 25 degree C in 25 ml pipetting reservoirs filled with loading solution (2 M glycerol + 0.8 M sucrose). For dehydration, the cryo-plates were transferred and immersed in 25 ml pipetting reservoirs filled with PVS2 for 20 min at 25 degree C. Then the cryo-plates were transferred in uncapped 2 ml cryotubes and directly plunged into liquid nitrogen. For rewarming, shoot tips attached to the cryo-plates were immersed in cryotubes containing 2 ml 1 M sucrose solution at room temperature. Using this procedure, regrowth of cryopreserved shoot tips of line 'Fukuyamajisei' reached over 90 percent. This protocol was successfully applied to 16 additional Mentha lines, with regrowth ranging from 73 percent to 100 percent. This V-Cryo-plate method will facilitate the cryostorage of mint germplasm in our genebank.


Asunto(s)
Criopreservación/métodos , Mentha/crecimiento & desarrollo , Brotes de la Planta/crecimiento & desarrollo , Vitrificación , Alginatos/química , Aluminio , Bancos de Muestras Biológicas , Criopreservación/instrumentación , Crioprotectores , Medios de Cultivo , Técnicas de Cultivo , Desecación/métodos , Geles , Glicerol , Concentración Osmolar , Sacarosa
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...