120 research outputs found
Ultrastuctural study of the phagocytic activities of splenic macrophages in tilapia (Oreochromis niloticus)
The main stages of the phagocytic process after the intraperitoneal injection of colloidal carbon to tilapia (Oreochromis niloticus), was ultra-structurally documented. Carbon particles were initially indiffuse form in the cytoplasm but they gradually formed discrete electron dense bodies that later fused with cytoplasmic granules to form phagolysosomes. Ultra structural results demonstrate that colloidalcarbon is actively phagocytized by cytoplasmic granules (lysosomes) in the spleen of O. niloticus. Direct phagocytic reaction of cells in the presence of an antigen is therefore very important in immunity
Seasonal variation in plants consumption pattern by foraging Olive Baboons (Papio anubis. Lesson, 1827) inside Kainji Lake National Park,
This study which lasted for eight (8) months in 2011, covering the period of dry and wet seasons examined seasonal plant species consumed by foraging Olive baboon (Papio anubis) inside Kainji Lake National Park, Nigeria. Data were collected in the morning between 8.00am - 12.00pm and in the evening between 2.00pm - 6:00pm. Plant species and their parts eaten were monitored and identified through direct observation and faecal analysis. It was observed that seven plants species ((Andropogon gayanus, Strychnos spinosa, Nuclear latifiora, Vitelaria paradoxa, Ficus sycomorus, Annona senegalensis and Tamarindus indica ) were consumed in the wet season with 303 feeding events while ten plants species (Detarium macrocarpum, Gardenia sotoemsis, Parkia biglobosa, Piliostigma thonningii, Pterocarpus erinaceus , Prosopis africana, Ficus sycomorus, Xamenia americana, Annona senegalensis and Vitex doniana) were consumed during the dry season with 315 feeding events. The feeding pattern shows that plants with higher nutritional quality were often consumed. Seasonal variation showed slight disparity in the nutrient composition of the identified plants. It was concluded that seasonal variations do affect the plants consumption pattern of foraging Olive baboon and that exsitu conservation of these plants is imperative for sustainable captive management of Olive baboon. © JASE
The Differential Susceptibility of Yoruba Ecotype Nigerian Indigenous Chicken Varieties To Newcastle Disease
This experiment was conducted to assess and compare the susceptibility of the varieties of Yoruba indigenous chicken ecotype: Yoruba Smooth Feathered (YSF), Yoruba Frizzled Feathered (YFF) and Yoruba Naked Neck (YNN) to Newcastle disease. A total of sixty (60) 16 weeks old chickens were used comprising of twenty (20) chickens per variety. The assessmentof their susceptibility to Newcastle disease was by evaluation of clinical signs, humoral response, mortality, pathology following contact with Newcastle disease infected chickens. The experimental chickens developed clinical signs of Newcastle disease from day 9 after infection. Haemagglutination inhibition (HI) titre was determined on days 0, 21and28 post-infection. On day 0, the HI titre of the 3 genotypes were below 3log2, on day 21, there were significant differences within the group (P<0.05) where in YNN had the highest mean HI titre of 7.5. Therewas decrease in the mean HI titre in all on day 28 with the YNN having the least reduction (P<0.05). The antibody titre against Newcastle disease was higher in the YNN than all the other varieties. The mortality commenced on day 10 after infection with 70% mortality in YSF, 40% in YFF and 30% in YNN. The proventricular, enteric and caecal tonsilar haemorrhages associated with the disease were more frequent and severe in YSF.This finding indicated that YFF and YSF may possibly be more susceptible to Newcastle disease than the YNN. It was concluded that indigenous chickens of Yoruba ecotype in Nigeria differ in their susceptibility to ND with YNN being possibly the most resistant to Newcastle disease followed by YFF and the least, YSF.Keywords: Hemagglutination inhibition, Newcastle Disease, indigenous Chicken, Ecotype, Varietie
The comparative susceptibility of commercial and Nigerian indigenous chicken ecotypes to Salmonella gallinarum infection
This study was to evaluate the possible genetic resistance of exotic and indigenous chicks to Salmonella gallinarum. A total of 72 nine weeks-old chicks were used for the study. The Fulani ecotype (Fulani smooth feathers - FSF), Yoruba ecotype (Yoruba smooth feathers - YSF), and the Exotic breed (Nera Black) chicks were infected with a dose of S. gallinarum (8.3 x 106 CFU) and were observed for 16 days. Evaluation of resistance was based on clinical signs, mortality, pathology, leukocyte count, bacterial count from liver and spleen of infected chicks. The highest peak for clinical signs in S. gallinarum infected chicks coincides with highest mortalities recorded on day 11-12 dpi and bacterial count of both liver and spleen on day 8. The lymphocytes count declined on day 8 for all the experimental chicks except for the exotic breed. There was no significant difference between the bacterial counts of the different groups on day 8. In S. gallinarum infected chicks, 94.4% of all the chicks showed clinical signs after infection, the exotic breed showed a prolonged clinical signs while the Yoruba ecotype showed the least. 87.5%, 80.0% and 37.5% mortality were recorded in the exotic breed, Fulani and Yoruba ecotypes respectively. The study showed that the exotic chicken (Nera Black) was more susceptible to Salmonella gallinarum infection. It also indicated that within the ecotypes in Nigeria, Fulani ecotype was more susceptible to Salmonella gallinarum infection than the Yoruba ecotype. The lower clinical signs and mortality observed in Yoruba ecotype indicated a resistance of the ecotype to S. gallinarum infection.Keywords: Ecotypes, Nigerian Indigenous chicken, Salmonella gallinarum infection
An international comparative study of blood pressure in populations of European vs. African descent
Background: The consistent finding of higher prevalence of hypertension in US blacks compared
to whites has led to speculation that African-origin populations are particularly susceptible to this
condition. Large surveys now provide new information on this issue.
Methods: Using a standardized analysis strategy we examined prevalence estimates for 8 white
and 3 black populations (N = 85,000 participants).
Results: The range in hypertension prevalence was from 27 to 55% for whites and 14 to 44% for
blacks.
Conclusions: These data demonstrate that not only is there a wide variation in hypertension
prevalence among both racial groups, the rates among blacks are not unusually high when viewed
internationally. These data suggest that the impact of environmental factors among both
populations may have been under-appreciated
A Systematic Mapping Approach of 16q12.2/FTO and BMI in More Than 20,000 African Americans Narrows in on the Underlying Functional Variation: Results from the Population Architecture using Genomics and Epidemiology (PAGE) Study
Genetic variants in intron 1 of the fat mass- and obesity-associated (FTO) gene have been consistently associated with body mass index (BMI) in Europeans. However, follow-up studies in African Americans (AA) have shown no support for some of the most consistently BMI-associated FTO index single nucleotide polymorphisms (SNPs). This is most likely explained by different race-specific linkage disequilibrium (LD) patterns and lower correlation overall in AA, which provides the opportunity to fine-map this region and narrow in on the functional variant. To comprehensively explore the 16q12.2/FTO locus and to search for second independent signals in the broader region, we fine-mapped a 646-kb region, encompassing the large FTO gene and the flanking gene RPGRIP1L by investigating a total of 3,756 variants (1,529 genotyped and 2,227 imputed variants) in 20,488 AAs across five studies. We observed associations between BMI and variants in the known FTO intron 1 locus: the SNP with the most significant p-value, rs56137030 (8.3×10-6) had not been highlighted in previous studies. While rs56137030was correlated at r2>0.5 with 103 SNPs in Europeans (including the GWAS index SNPs), this number was reduced to 28 SNPs in AA. Among rs56137030 and the 28 correlated SNPs, six were located within candidate intronic regulatory elements, including rs1421085, for which we predicted allele-specific binding affinity for the transcription factor CUX1, which has recently been implicated in the regulation of FTO. We did not find strong evidence for a second independent signal in the broader region. In summary, this large fine-mapping study in AA has substantially reduced the number of common alleles that are likely to be functional candidates of the known FTO locus. Importantly our study demonstrated that comprehensive fine-mapping in AA provides a powerful approach to narrow in on the functional candidate(s) underlying the initial GWAS findings in European populations
Engineering III-V nanowires for optoelectronics: from epitaxy to terahertz photonics
Downloading of the abstract is permitted for personal use only. Nanowires show unique promise as nanoscale building blocks for a multitude of optoelectronic devices, ranging from solar cells to terahertz photonic devices. We will discuss the epitaxial growth of these nanowires in novel geometries and crystallographic phases, and the use of terahertz conductivity spectroscopy to guide the development of nanowire-based devices. As an example, we will focus on the development of nanowire-based polarization modulators for terahertz communications systems
Development of an Alumni Feedback System for Curriculum Improvement in Building Technology Courses
In this fast-paced world, the needs of the world of work and the global market is
changing at an unprecedented speed. Therefore, institutions of higher learning need to
constantly adjust their programs to fit into these needs. The study aimed to develop an
alumni feedback system for curriculum improvement in Building Technology courses.
The study highlighted the benefits of an alumni feedback system compared to a manual
questionnaire method or other methods of curriculum improvement. The web-based
system was designed through use case and system block diagrams. Thereafter, the webbased
system was programmed using HTML, CSS, MySQL and PHP. Screenshots of the
web-based system was presented. The alumni feedback system comprises of
background information of the alumni, perception test on the impact of the course
content and a review of the course content for curriculum improvement. Since this is a
preliminary study, future studies would be based on analyzing data obtained in the
database in terms of the numerical and text data. This study can be adapted for other
programmes for the purpose of curriculum improvement
Replication of genome-wide association studies (GWAS) loci for fasting plasma glucose in African-Americans
Assessment of Surface Water Contamination from Coalbed Methane Fracturing-Derived Volatile Contaminants in Sullivan County, Indiana, USA
There is a growing concern over the contamination of surface water and the associated environmental and public health consequences from the recent proliferation in hydraulic fracturing in the USA. Petroleum hydrocarbon-derived contaminants of concern [benzene, toluene, ethylbenzene, and xylene (BTEX)] and various dissolved cations and anions were spatially determined in surface waters around 14 coalbed methane fracking wells in Sullivan County, IN, USA. At least one BTEX was detected in 69% of sampling sites (n=13) and 23% of sampling sites were found to be contaminated with all of the BTEX. Toluene was the most common BTEX compound detected across all sites, both upstream and downstream from coalbed methane fracking sites. The calcium (~60 ppm) and sulfates (~175 ppm) were the dominant cations and anions, respectively, in surface water around the fracking sites. This study represents the first report of BTEX contamination in surface water from coalbed methane hydraulic fracturing wells
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