Biosciences

Health and hygiene are the primary requirements for human beings to live comfortably and work with maximum efficiency. Mosquitoes home in on people because they give off carbon dioxide, lactic acid, body odor and heat. A mosquito repellent textile protects the human beings from the bite of mosquitoes and thereby promising safety from the diseases like malarial fever. There are many natural plant products, which show mosquito repellent properties. Extracts from roots, stem, leaves, flowers, fruits and seeds of diverse species of plants exhibit mosquito repellent properties. These extracts can be used as textile finishing agents in the crude form or as microcapsules to enhance the durability and controlled release of the extracts. Lemon grass is one such plant well known for its medicinal properties. In the present study, 100% polyester fabric was finished with lemon grass oil to check for its mosquito repellent properties. The results show that, the microencapsulated polyester fabric showed highest mosquito repellent activity (92%) when compared with the fabric finished by pad dry cure method. FTIR analysis of the microcapsules finished fabric also reveals additional functional groups imparted to the fabric by microencapsulation compared to the control.

Altogether 272 species and infraspecific taxa of algae and cyanobacteria were identified in the Enguri River habitats during 1974-1977, and 2014 field trips. Total list of algal flora including our findings and reference lists is represented by 339 taxa (excluding diatoms) and most of them were bio-indicators. Charophyta, Cyanobacteria and Chlorophyta species were dominated in communities. Altitude play the major role in distribution patterns of algal diversity and ecological groups of water quality indicators.

Microalgae are considered to be the world’s future energy reservoir and various aspects have been followed for optimizing the algae growth for large scale production of biodiesel. For the same, selection and screening of microalgae strain for its lipid productivity is much more important. Fourier transform infrared (FTIR) spectroscopy was used in this study for the analysis of lipid extract from natural isolate of Chlorella vulgaris. In order to evaluate the strain productivity the reference strain was obtained. Both the cultures were grown in a chemically-defined media under photoautotrophic culture conditions. Lipid extraction procedures were standardized for both strains based on Fourier transform infrared (FTIR) spectroscopy .The extracted lipid samples were analyzed. This study reveals that the natural isolate identified as Chlorella vulgaris strain is suitable for further optimization procedures and found with high percentage of residual lipid proportions. Also the results show that FTIR technique can be applied for determination of single cell biomass composition from phytoplankton communities.

Over the past years, malaria was a major public health problem in Eritrea. But since 1998, it has experienced a dramatic decline in malaria incidence. In 2013, the MoH launched a massive expansion of the malaria prevention and control program. The program was aimed mainly at the reduction of malaria in populations living in all zobas of the country in general and in the malarious areas in particular. Since Endagergis is one of the malarious areas in Eritrea, the Government put much effort to reduce morbidity and mortality rates in this area. However, there is still a need to generate new information on the prevalence of malaria at the villages of Endagergis locality at the moment. A total of 30 blood slides were examined. Out of these 6 (20%) (95% CI; 5% - 34.9%) were found to be infected. The malaria parasite prevalence differed markedly among villages from 0 to 2.2%, with 40% of the five villages having no positive cases. Four (13.3%) of positive slides had P. falciparum and two (6.7%) had P. vivax. Among the total tested, 4 (28.6%) of the males and 2 (12.5%) of the females had malaria infection and infection was occurred in all age groups, with a slightly higher prevalence (66.7%) of the parasite observed in age groups of below 15 years old. This study reports a significant drop in the prevalence of malaria infection in the inhabitants of Endagergis locality, due to an appropriate implementation of many preventive strategies. However, malaria prevalence still exists in some areas of the locality and is strongly associated with presence of mosquito breeding sites. The prevalence varies according to location of villages with Endagergis, AdiGuor and AdiSeyabo showing statistically higher prevalence. Malaria prevalence was higher in August 2012 than in other months of the surveillance periods.

Simulating is an effective method to identify and comprehend the abstract and complex phenomena. In order to find the point of penetration of memory in the human brain, we put forward an idea to simulate memory function using ant action by their similarities. By analysis of their structure and action, we discuss the brain functional memory complex network like the ant network, the results imply that it is feasible to make research on brain functional memory complex network with the theory of ant action and colony optimization.

Effects of caterpillar (Imbrasia truncate Aurivillius, 1908) meal as a protein source in the diet of Oreochromis niloticus were investigated on growth performance, feed efficiency, whole body mineral composition and the cost/benefit analysis. The experiment was conducted in a completely randomized design with duplicate observations (3 treatments × 2 replicates × 35 fish per hapa-in-earthen pond systems) during ten weeks of duration using an open system. Water temperature and dissolved oxygen ranged respectively between 27.7 to 28°C and 4.5 to 6.0 mg l-1. The Nile tilapia (12.67±1.88 g initial body weight and 10.45 ± 0.03cm initial length) were fed three times a day with three calculated isonitrogenous and isoenergetic diets prepared by replacing fishmeal with caterpillar meal at 15% and 30%. The diets were coded T1 and T2 respectively. A control diet without caterpillar meal was coded T0. The fish fed with T1 and T0 diets were superior in specific growth rate (p< 0.05) when compared with fish fed with diet T2 treatment. On the other hand, the feed utilization parameter: feed conversion ratio (FCR), did not show significant differences(p? 0.05) between the fish in the control group and diet T1, although a significant difference between T1 andT2 treatments was observed. Results of body composition in response to dietary treatments showed no significant statistical difference (p>0.05) for moisture, fiber and minerals in contrast to protein, lipid and ash content where the difference was significant (p<0.05).The highest profit index (1.82) was recorded on diet T2. The lowest profit index was in the control but the differences were not significant (p? 0.05).These results indicate that incorporation of less than 30 % of caterpillar meal as a substitute for fishmeal could be feasible in the diet of Nile tilapia. Further studies are recommended for other fish species such as catfish, and the conditions to optimize the level of that ingredient to improve growth performance.

Currently many bacteria have been exploited for production of biopolymers for various industrial applications. The need for biopolymers has been increasing constantly along with increase in human needs. In the present study two important biopolymers- edo polymer (PHA) and exopolymer (EPS) was extracted and characterized from the Bacillus sp. 2-11. The ability of Bacillus sp.2-11 to produce PHA was identified by simple and rapid Sudan black B staining method. Similarly the presence of exopolysaccharides was identified by Alcian Blue staining method. The ability of the organism to utilize cheap substrates as carbon source for polyhydroxyalkonates (PHA) and exopolysaccharide (EPS) production was determined. Rice bran, wheat bran, molasses and sago liquid wastes were supplemented as carbon substrate in nitrogen free production medium. The most suitable carbon source was sago liquid waste as it showed 42.15% and 50.80% PHA and EPS yield respectively. It was also observed that PHA yield was growth associated whereas EPS production was observed at the late exponential phase. Both FT-IR and GC-MS analysis confirmed the presence of PHA and EPS in Bacillus sp.2-11

The antibacterial activity of methanolic crude extract of Diacure, a polyherbal formulation was investigated against Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterococcus faecalis, Micrococcus luteus, Escherichia coli and Candida albicans as test strains at different concentrations (80, 90 and 100?l/disc). Better antibacterial activity was observed with the extracts of diacure, that showed excellent inhibitory activity against Klebsiella pneumoniae, Escherichia coli and Candida albicans at concentration of 100 ?l/disc. Among different bacteria tested Klebsiella pneumoniae, Escherichia coli and Candida albicans were found to be more sensitive to crude extract when compared to others. HPLC analysis of the crude extract of diacure, a polyherbal formulation of 11 medicinal plants showed four different Phenolic acids (Tannic acid, Gallic acid, Ferulic acid and Caffeic acid). The results of the study provide scientific basis for the use of the plant extract in the future development as antioxidant, antibacterial, antifungal and anti-inflammatory agent.

The noninfectious disease, diabetes increases the risk of the infectious disease TB. In developing countries TB remains a major cause of mortality and in these countries the prevalence rate of diabetes in increasing rapidly. In this study, totally 1200 number of TB clinic attendees were included and blindly screened for the diabetes. Random blood sugar was checked for the selected population. Blood samples were tested by glucometer. Out of 1200 TB clinic attendees, diabetes was diagnosed with 750 patients (63%). From our study, we conclude that the TB clinic attendees are at high risk and showing high percentage of DM. We also suggest that the danger of the co-existence of TB and DM should be explored and to be taught to the society especially to the TB clinic attendees to ensure the effective treatment.

The new shielding using a mixed of Barium Sulfate (BaSO4) and cement accordingly to the ratio that desired which is from (1:99) to (20:80) respectively. The samples were in thickness of 1 mm, 5 mm and 10 mm with the ratio of BaSO4 are 0, 5, 10, 15, and 20%.The samples are examined with XRD. The mixture ratio of barium sulfate that has 20% in the sample shows that the absorption of the energy is high. A high mass density material of sample as barium, which has high atomic number is suitable to absorb the energy of radiation. Increasing the material density leads to increase the attenuation. The results have shown a significant protection for hazardous of gamma ray.