Determination of 40K, 226Ra and 228Ra concentrations with dose rates in crayfish from Ode Omi River and radiological implications to the consumers

Natural radionuclides such as 40K, 226Ra and 228Ra are found naturally in water and sediments of rivers, likewise in soils. They are transferred to aquatic animals through ingestion. Radioactivity concentrations and dose rates of 40K, 226Ra and 228Ra in crayfish species from Ode Omi River in coastal region, Ogun State Southwest of Nigeria were determined by gamma spectrometry using NaI (TI) detector coupled with a pre-amplifier base to a multiple channel analyzer (MCA). 15 samples of crayfish were collected. Cherax tenuimanus had the highest mean concentration and dose rate of values 106.87 ± 9.11 Bq kg–1 and 0.00960 mGy hr–1 respectively for 40K. Moreso, for 226Ra, Cherax quadricarinatus had the highest mean concentration and dose rate of values 2.57 ± 0.82 Bq kg–1 and 4.50 x 10–7 mGy hr–1 respectively. Concerning228Ra, Astacopsis gouldi had the highest mean concentration and dose rate of values 5.23 ± 0.46 Bq kg–1 and 5.86 x 10–13 mGy hr–1, respectively. The average dose rate of the radionuclides in all the crayfish was calculated to be 4.62 x 10 ̶ 3 mGy hr–1 which was below the 0.4 mGy hr–1 limit recommended. The average annual committed effective dose and average excess lifetime cancer risk of all the radionuclides to the consumers were 0.0807 mSv yr–1 and 0.589 x 10–4, respectively, which were below global limits of 1.0 mSv yr–1 and 0.29 x 10–3, respectively, therefore, the ingestion of these natural radionuclides could not pose any radiological health hazards to the aquatic animals, likewise man the consumers. Keywords: Radionuclide concentration, Dose rate, Cancer Risk

Web readability factors affecting users of all ages

With the increase in the growth of internet since 1990 WorldWide Web have gained a worldwide popularity.Web has become an ultimate source of information throughout the world. The web has been a source of information, knowledge, entertainment and carrying out different tasks such as online shopping, reservation etc. Every one finds ways to the web due to easiness of access and the bulk of information that has been available so ways to make web more attractive and easy to interact with has been an issue under discussion since its inception. In this paper we have focused how to make a webpage more usable for different age group in terms of readability. We have focused on eight eternal readability factors i.e. color contrast, white space, line spacing, font style, font size, text width, headings, graphics and animation. These eight factors are compared that how different age group people behave with the web applications by varying these eight factors. Based on literature review we have proposed an idea that how to make web more readable for people of different age groups e.g. children, teenagers and old /senior users

Investigation of the Vertical Profile Radio Refractivity Gradient and Effective Earth Radius Factor (k-factor) in Transmission Link Over Oyo, Oyo State, South Western Nigeria

Surface radio refractive gradient and k-factor are very imperative in observing propagation conditions, designing and planning of microwave communication links in the lower part of the atmospheric boundary layer. The measurement of weather variables (air temperature, atmospheric pressure, relative humidity and wind speed) were conducted in this study at the School of Science, Emmanuel Alayande College of Education, Oyo (7.83°N, 3.95°E), Oyo State, Nigeria. The research was carried out for a period of one year (January to December, 2020) using self-designed cost effective portable weather monitoring systems. The systems were sited from the ground to a height of 200 m on a 220 m Nigeria Television Authority (NTA) UHF channel 37 tower at Oke-Apitipiti in Oyo Town of Oyo State. The calculated daily and monthly averages data are employed to investigate the vertical surface radio refractivity and its refractivity gradient. The highest value of -1.093E+26 N-units/km was recorded in January, while the month of July experienced the least of about -9.305E+19 N-units/km. The months of January–July verified sub-refractive conditions with propagation conditions having varying degree of occurrence. On the other hand, super-refraction and ducting were recorded mostly between August–December from the study. The results also find applicability in radio engineering for refining VHF/UHF terrestrial links based on clear-air considerations which will support operational planning of terrestrial radio networks in Oyo, South Western Nigeria Keywords: Microwave; k-factor; refractivity gradient; sub-refractive; super-refractio

An agent based architecture for cognitive spectrum management

In the recent years, wireless technologies and devices have progressed dramatically that has augmented the demand for electromagnetic spectrum. Some research work showed that spectrum access and provision to user is not possible due to shortage of spectrum but federal communication commission refused to accept this theory and indicated that the spectrum is available since most of the frequency bands are underutilized. In order to allow the use of these frequency bands without interference, cognitive radio was proposed that characterizes the growing intelligence of radio systems can adapt to the radio environment, allowing opportunistic usage and sharing with the existing uses of spectrum. To take this concept a step further, we propose to use intelligent agent for spectrum management in the context of cognitive radio in this paper. In our proposed architecture, agents are embedded in the radio devices that coordinate their operations to benefit from network and avoid interference with the primary user. Agents carry a set of modules to gather information about the terminal status and the radio environment and act accordingly to the constraints of the user application

Rabies in a Vaccinated 9-Month-Old German Shepherd Dog, Akure, 2010: A Case Report

After the onset of symptoms, the clinical course of rabies is almost invariably fatal. Rabies has traditionally been associated with dogs more than any other animal, and in parts of the world where domestic animal control and vaccination programs are limited, dogs remain the most important reservoir of the disease. We report a case of canine rabies in a vaccinated 9-month-old German shepherd female dog. The presenting clinical sign was jaw muscle paralysis with a hanging bronze color like tongue without salivation. Following encephalectomy, a rabies positive diagnosis was confirmed by fluorescent antibody technique at the Rabies Laboratory, National Veterinary Research Institute, Vom. The epidemiology of the rabies case is not understood. This case is of public health significance because of the at-risk population including animal health care service provider and animals. The following were recommended, (a) a reinvigorated control measure that includes the awareness program on prevention, responsible dog ownership with dog registration at veterinary hospitals, and registered veterinary clinics by the government and (b) a yearly rabies vaccination campaign that must be improved through the veterinary public health and other health departments collaborating

Synthesis, characterisation and DNA intercalation studies of regioisomers of ruthenium (II) polypyridyl complexes

Regioisomers of the functional group of the main ligand (L) on a series of [Ru(phen)2L]2+and [Ru(bpy)2L]2+ complexes, where phen is 1,10 phenanthroline and bpy is 2,2′-bipyridine, were synthesised to investigate the interaction with deoxyribonucleic acid (DNA) as potential therapeutics. UV–Vis binding titrations, thermal denaturation and circular dichroism were used to evaluate their interaction with DNA. The conclusions indicated the significance of the auxiliary ligand; especially 1,10-phenanthroline has on the binding constants (Kb). The systematic variation of auxiliary ligand(phen or bpy), and polypyridyl ligand (4-(1H-Imidazo[4,5-f][1,10]phenanthrolin-2-yl)benzonitrile (CPIP), 2-(4-formylphenyl)imidazo[4,5-f] [1,10] phenanthroline (FPIP), 2-(4-bromophenyl)imidazo[4,5-f][1,10]phenanthroline (BPIP) and 2-(4-nitrophenyl)imidazo[4,5-f] [1,10] phenanthroline (NPIP), split in terms of functional group change were investigated for DNA interaction. The CPIP analogues in particular were investigated for the regioisomerism (ortho, meta, para) effect of the nitrile group on the ligand. It was found that both the DNA interaction could be tailored through the systematic variation of the electronic nature of the individual auxiliary ligand and to a lesser extent the functional group and regioisomeric change. Preliminary cell line studies have been carried out to determine the selectivity of the complexes against cell lines such as A375 (Skin Cancer), HeLa (Cervical Cancer), A549 (Lung Cancer), Beas2B (Lung Normal Cell) and MCF-7 (Breast Cancer). Complexes which had strong DNA interactions in the binding studies have proven to be the most efficacious against certain cell lines. Establishing well-defined structure property relationships when looking at trends in spectroscopic properties and DNA binding will aid in the intelligent design of potential therapeutic complexes

STUDY THE MATERIALS AND MECHANICAL PROPERTIES OF NI-25% WT TA ALLOY

Nickel and Tantalum alloys have a wide range of capabilities biomedical applications due to its high degree of biocompatibility, Favorable mechanical properties and high corrosion resistance The possibility of Osseointegration. In this study, all the alloys were prepared by powder metallurgy Then the alloying element (indium as a binder with different structural composition) in different groups (0.6, 0.7, and 0.8 wt.%) to the main alloy (75 wt.% Ni-25wt% Ta) for to study the effect of these elements on microstructure characterization (XRD, SEM, EDS, XRF and light optical microscopy) and mechanical properties (compression, hardness, Wet sliding corrosion tests) for this alloy. The compact pressure was determined as 800MPa and the green alloyed sintered at 700 oC for 5h in inert gas (Argon), then the samples cooled in the furnace

Beyond the Task: Developing a Tool to Measure Workplace Characteristics That Affect Cognitive Load and Learning

PURPOSE: Educators lack tools to measure the workplace characteristics that learners perceive to affect learning. Without a tool that encompasses the social, organizational, and physical components of workplace learning environments (WLEs), it is challenging to identify and improve problematic workplace characteristics. Using echocardiography WLE, this study developed a tool to measure workplace characteristics that cardiology fellows perceive to affect learning. METHOD: The Workplace-Cognitive Load Tool (W-CLT) was developed, which encompasses 17 items to measure workplace characteristics that could affect perceived cognitive load and learning. Exploratory factor analysis was used to identify the most parsimonious structure. A total of 646 cardiology subspeciality fellows were recruited from 60 cardiology fellowship programs to complete the survey between November 2020 and February 2021. Validity evidence was collected, guided by the unified model of validity. RESULTS: A total of 308 fellows (response rate, 49%) participated in the survey. The most parsimonious structure included 4 factors: (1) workplace-task, (2) workplace-environment, (3) workplace-orientation, and (4) workplace-teaching and feedback. All factors had high reliability (Cronbach α = 0.92, 0.92, 0.96, and 0.94, respectively). Social, organizational, and physical components of WLEs were represented in the items. Workplace-teaching and feedback had moderate negative correlations with workplace-environment (r = -0.41, P \u3c .001) and workplace-orientation (r = -0.36, P \u3c .001). A moderate positive correlation was found between workplace-task and workplace-teaching and feedback (r = 0.42, P \u3c .001). Workplace-task had weak negative correlations with workplace-environment (r = -0.22, P \u3c .001) and workplace-orientation (r = -0.23, P \u3c .001). CONCLUSIONS: The W-CLT measures workplace characteristics that cardiology fellows perceive to affect their learning. The presence of social, organizational, and physical components emphasizes how workplace characteristics can enhance or impede learning. The W-CLT provides a foundation to explore how learning can be optimized in other WLEs

ANALYSIS OF GALVANIC CORROSION UNDER MASS TRANSFER CONTROLLED CONDITIONS

Because of practical importance of protecting industrial equipments from galvanic corrosion, the need arises to analyze the effects of variables, such as temperature, velocity, and area fraction of  metals on galvanic corrosion in systems under mass transfer control as in seawater (pH=7). For these reasons the galvanic corrosion of Fe-Zn is analyzed to study the influence of Reynolds number, temperature, and area fraction on the galvanic corrosion rates and galvanic corrosion potential under mass transfer control. It is found that galvanic corrosion rate of more active metal (Zn) is increased with Reynolds number while the corrosion rate of more noble metal (Fe) is slightly increased with Re depending on the galvanic potential that depends on the area fraction. Increasing Reynolds number shifts the galvanic potential to more positive values. Also increasing temperature leads to shift the corrosion potential to more negative values and to change the corrosion rate of more active metal (Zn) depending on two parameters oxygen solubility and oxygen diffusivity. As area fraction of more active metal (Zn) increased the galvanic potential is shifted to the negative anodic direction while the corrosion rate for more noble metal is decreased