Antifouling activity of alkaline protease from halotolerant Bacillus sp. isolated from marine source

1274-1279In this study, an attempt has been made to explore the antifouling activity of the marine halotolerant bacterium, namely, Bacillus sp. About 10 different bacteria were isolated using the Zobell marine agar medium from the marine sediment samples that were collected from the Marina beach, Bay of Bengal, India. The growth pattern tests of the 10 bacteria were documented. Among the 10 different isolates, two exhibited the protease activity in skim milk agar. The antifouling activity was further tested against five different fouling bacteria. The antifouling activity of alkaline protease isolated from Bacillus sp. inferred that it exhibited pronounced inhibitory zones against fouling bacterial strains with least minimal inhibitory concentration range between 25 and 100 units/mg protein. Anticrustacean assay was performed using Artemia salina of alkaline protease, which showed good activity. The results suggest that Bacillus sp. produced an extracellular alkaline protease, which was responsible for the antifouling and algicidal activity of marine fouling organisms. This study tends to indicate that Bacillus sp. could be further explored for the development of new antifouling agents

A synopsis on the effects of anthropogenic greenhouse gases emissions from power generation and energy consumption

Despite the looming difficult energy context in the majority of countries in the world, global change in environmental dignity resulting from power generation and energy consumption scenario is rapidly becoming a globally disturbing phenomenon. Stakeholders and environmental activists alike have been clamouring for adoption of reduction procedures using sustainable means because ignominious environmental practices have associated disastrous consequences. Increasing essential strategies are needed to fortify the pursuit for the reduction in the emissions from power generation and energy consumption. Therefore, this article presents an overview of the effects of anthropogenic energy generation and consumption practices capable of ejecting emissions of greenhouse gases into the atmosphere. It also endeavors to identify some greenhouse gas emission reduction and control measures

Effects of Phosphorus and Rhizobium Inoculation on Yield Components and Grain Yield of Some Selected Cowpea Genotypes

The effects of phosphorus (0, 20, 40kg P2O5ha-1) and rhizobium inoculation (inoculated and un-inoculated) on the yield components and grain yield of three cowpea genotypes (IT93K-452-1, IT97K-573-1-1 and IT98K-499-35) were investigated under field conditions at Bayero University, Kano, Teaching and Research Farm (11059 N; 8025 E; 466m above sea level) and Agricultural Research Station Farm, Minjibir (12010’ N,  8039’ E; 402m  above sea level) in 2014 rainy season. Cowpea genotypes were assigned to the main plot, while phosphorus levels were assigned to the sub-plots. The inoculation was assigned to the sub-sub plot. These were laid out in Split-split plot design and replicated three times. Results of the study indicated significant effect of genotype in all the characters measured except shelling percent. Significantly (p˂ 0.05) higher number of pods per plant, pod weight, fodder and grain yield was observed from IT99K-573-1-1 than all other genotypes evaluated. Similarly, the number of pods per plant, pod weight, fodder and grain yield were significantly influenced by application of phosphorus with better results recorded from 40 kg P2O5 treated plants. Inoculation of cowpea with rhizobium MC92 strain, also recorded significant effect on the measured characters and grain yield. Inoculation of cowpea with rhizobium MC92 along with 40kgP2O5 ha-1 could enhance performance of cowpea particularly with an adaptable genotype like IT99K-573-1-1. Keywords: Cowpea, grain yield, inoculation, yield component

Coverage of hospital-based cataract surgery and barriers to the uptake of surgery among cataract blind persons in nigeria: the Nigeria National Blindness and Visual Impairment Survey.

PURPOSE: To determine cataract surgical coverage, and barriers to modern cataract surgery in Nigeria. METHODS: Multistage stratified cluster random sampling was used to identify a nationally representative sample of 15,027 persons aged 40+ years. All underwent visual acuity testing, frequency doubling technology visual field testing, autorefraction, and measurement of best corrected vision if <6/12 in one or both eyes. An ophthalmologist examined the anterior segment and fundus through an undilated pupil for all participants. Participants were examined by a second ophthalmologist using a slit lamp and dilated fundus examination using a 90 diopter condensing lens if vision was <6/12 in one or both eyes, there were optic disc changes suggestive of glaucoma, and 1 in 7 participants regardless of findings. All those who had undergone cataract surgery were asked where and when this had taken place. Individuals who were severely visually impaired or blind from unoperated cataract were asked to explain why they had not undergone surgery. RESULTS: A total of 13,591 participants were examined (response rate 89.9%). Prevalence of cataract surgery was 1.6% (95% confidence interval 1.4-1.8), significantly higher among those aged ≥70 years. Cataract surgical coverage (persons) in Nigeria was 38.3%. Coverage was 1.7 times higher among males than females. Coverage was only 9.1% among women in the South-South geopolitical zone. Over one third of those who were cataract blind said they could not afford surgery (36%). CONCLUSIONS: Cataract surgical coverage in Nigeria was among the lowest in the world. Urgent initiatives are necessary to improve surgical output and access to surgery

Incidental finding of autosomal dominant polycystic kidney disease in a 52-year-old man: a case report.

Autosomal dominant polycystic kidney disease (ADPKD) also known as Adult Polycystic Kidney Disease (APKD) is one of the most common systemic hereditary diseases. The disease usually presents between 20 to 39 years of age, although milder forms may not present until over 60 years and absence of renal failure has been rarely observed in some patients up to 80 years of age. Three distinct gene defects have been implicated in the pathogenesis of APKD designated as PKD1, PKD2, and PKD3. Patients with APKD may be asymptomatic, or may usually present with hypertension (in 50-70% of cases), renal insufficiency, and the complications of multiple cysts (haematuria, pain and infection) or as an abdominal mass discovered on incidental clinical or imaging examination. APKD is said to be rare in Africans. Case report: We report a case of an incidental finding of autosomal dominant polycystic kidney disease (ADPKD) in a 52-year-old normotensive man with a normal renal function test. Haematuria, dysuria and low-grade fever were the presenting complaints. The role of radiology in the diagnosis and management of ADPKD was highlighted. Conclusion: Although APKD is rare in Africans, a high index of suspicion for the disease is essential for the diagnosis of the disease especially in elderly patients with a family history of APKD who present with haematuria associated with multiple renal cysts

Microwave assisted K2CO3 palm shell activated carbon as sorbent for CO2 adsorption application

Carbon dioxide is believed to be a major greenhouse gas (GHG) that contributes to global warming. In this study, palm shells were used as a precursor to prepare CO2 activated carbon sorbents via carbonization, chemical impregnation with K2CO3 and microwave activation. Adsorption equilibrium data for CO2 adsorption on the porous carbon were obtained at different temperatures using static volumetric adsorption method. Langmuir, Freundlich, Sips and Toths models were used to correlate the experimental data. The CO2 adsorption capacity at 303.15, 343.15, 378.15 443.15 K and 1 bar on the sorbent was 2.71, 1.5, 0.77, 0.69 mmol/g respectively. Sips isotherm was found to have the best fit. The results indicated that the porous carbon sorbent prepared by carbonization and microwave K2CO3 assisted activation have good CO2 uptake. The porous carbons produced are therefore good candidates for CO2 adsorption applications

Simulation of Hydrodesulphurization (HDS) Unit of Kaduna Refining and Petrochemical Company Limited

This research was carried out to simulate the Hydrodesulphurization unit using ASPEN HYSYS with the aim of removing impurities such as Sulphur, Nitrogen and Oxygen in raw Kerosene. The simulation is based on conditions and parameters (mass flow rates, temperature and pressure readings) obtained from the Linear Alkyl Benzene (LAB) plant of the Kaduna Refining and Petrochemical Company (KRPC). After the successful completion of the simulation, total removal of impurities was achieved as the concentration of sulphur, nitrogen and oxygen in mole fraction present in the treated Kerosene stream was approximately zero. The treated Kerosene composition indicated 0.0021, 0.3342, 0.3322 and 0.3315 mole fractions of n-C13, n-C14, n-C15 and n-C16 respectively. Key words: Simulation, Hydrodesulphurization, Aspen Hysys, Impurities

Solid State Fermentation of Orange Pomace for Bioethanol Production

This study is aimed at studying the effect of process variables on solid state fermentation of orange pomace for bioethanol production using Saccharomyces cerevisiae. The effect of substrate concentrations (100 - 350 g), fermentation period (24 - 72 hours) and inoculum amount (2.0 - 4.5 g) on solid state fermentation of orange pomace for bioethanol production was investigated. Characterization of the resulting bioethanol was carried out to determine its fuel properties (viscosity, flash point, density, refractive index, specific gravity, pH and boiling point). Experimental results revealed increase in the process variables (substrate concentration, fermentation period and inoculum amount) led to a corresponding increase in bioethanol yield until an optimum condition was reached (substrate loading of 200 g, pH of 4.5, fermentation temperature of 35°C, inoculum amount of 3 g and fermentation period of 72 hours) after which a decline in yield was observed. The maximum ethanol yield of 32.32 % v/v was obtained at these condition. Characterization of the bioethanol sample showed that the ethanol has satisfactory fuel properties that establishes its suitability as an alternative renewable fuel that can be blended with gasoline

The Achievable Rate of Interweave Cognitive Radio in the Face of Sensing Errors

Cognitive radio (CR) systems are potentially capable of mitigating the spectrum shortage of contemporary wireless systems. In this paper, we provide a brief overview of CR systems and the important research milestones of their evolution, along with their standardization activities, as a result of their research. This is followed by the detailed analysis of the interweave policy-based CR network (CRN) and by a detailed comparison with the family of underlay-based CRNs. In the interweave-based CRN, sensing of the primary user's (PU) spectrum by the secondary user's (SU) has remained a challenge, because the sensing errors prevent us from fulfilling the significant throughput gains that the concept of CR promises. Since missed detection and false alarm errors in real-time spectrum sensing cannot be avoided, based on a new approach, we quantify the achievable rates of the interweave CR by explicitly incorporating the effect of sensing errors. The link between the PU transmitter and the SU transmitter is assumed to be fast fading. Explicitly, the achievable rate degradation imposed by the sensing errors is analyzed for two spectrum sensing techniques, namely, for energy detection and for magnitude squared coherence-based detection. It is demonstrated that when the channel is sparsely occupied by the PU, the reusing techniques that are capable of simultaneously providing low missed detection and false alarm probabilities cause only a minor degradation to the achievable rates. Furthermore, based on the achievable rates derived for underlay CRNs, we compare the interweave CR and the underlay CR paradigms from the perspective of their resilience against spectrum sensing errors. Interestingly, in many practical regimes, the interweave CR paradigm outperforms the underlay CR paradigm in the presence of sensing errors, especially when the SNR at the SU is below 10 dB and when the SNR at the PU is in the range of 10-40 dB. Furthermore, we also provide rules of thumb that identify regimes, where the interweave CR outperforms the underlay CR

Effects of rice husk ash on durability of self-compacting concrete made with cassava peel ash

Self-compacting concrete (SCC) is a highly flowable concrete with improved strength and surface smoothness. The preparation of SCC requires high amount of cement. This utilizes tremendous amount of energy and releases carbon dioxide into the atmosphere. It is critical to reduce CO2 emissions during Portland cement (PC) manufacture by partially replacing cement in the SCC. This study evaluates the durability characteristics of SCC produced using cassava peel ash (CPA) combined with rice husk ash (RHA) at 5, 10, 15, 20, and 25 percent cement replacement levels respectively. The effects of water absorption, H2SO4 attack, MgSO4 attack, and high heat on SCC made with CPA and RHA blends were examined. The results show that, as CPA and RHA proportions rise by approximately 5% CPA and 10% CPA+RHA substitution, SCC compressive strength equates to design strength (grade 35). It was also discovered that CPA and RHA both enhance resistance to H2SO4 and MgSO4 degradation, but perform poorly when exposed to elevated temperatures when compared to the control specimen. However, when CPA is utilized with RHA in SCC, the rate of water absorption is reduced to a minimum due to an enhanced pore structure of the CPA-SCC specimen. Generally, a 5% CPA content is considered as the optimum replacement of cement for self-compacting concrete with grade 35