Radiation measurements with mixed field from neutrons and gamma radiation are complicated. In the recent work, two types of neutron sources (252Cf and Pu-α-Be) have been used. The neutron spectra of these sources have been traced using neutron/gamma spectrometer with stilbene scintillator. This spectrometer could discriminate between pulses produced by recoil proton and those produced by recoil electron using a double different method. Measurements were performed to study the dependency of slow neutron and gamma in polypropylene and steel on the spectrum shape of the radiation penetration. A BF3 and TLD-600 detectors measured the slow neutron flounce and TL-Intensity, while TLD-700 detectors measured the gamma TL-Intensity. The slow neutron flounce and total TL-Intensity for neutrons and gamma were measured behind different thicknesses of the investigated materials. The measuring values gave the form of distribution relations, which indicates the dependency of dose value on the incident field and the atomic weight of the penetrated material.

There is serious concern at South African institutions over the low pass-rate of Black students\nin the fields of science despite the strategies implemented to deal with the problem. Students’\nperformance are influenced by their biographical associations and previous performance\namong other external factors. In this research we use a Bayesian approach to identify at-risk\nstudent biographical profiles by contextualising the student using biographical and enrollment\nobservations. The main contributions of this paper are: (a) a data driven indication of the\ninfluence of four biographical characteristics (i.e. gender, spoken home language, home\nprovince, and race description) on student aggregates; (b) a trajectory of student performance\nwith respect to biographical characteristics over the period 2008 to 2017; and finally, (c) a list\nof biographical profiles explicitly indicating a Bayesian probability of failing to complete the\nminimum requirements for a Mathematical Science degree given the biographical profile. The\nresults showcased at-risk biographical profiles with a Bayesian estimate that was greater than\n0:7 for failing to complete the requirements for a degree in the Mathematical Sciences. From\nthis list the majority of the at-risk biographical profiles were female; at-risk biographical\nprofiles specified English (29%) and South Sotho (13%) as being eminent spoken home\nlanguages; MP (17%), GA (14%), FS (13%) and NW (13%) as being notable provinces; and\nfinally, the majority of at-risk biographical profiles have an associative Black race description\n(71%), followed by Coloured (12%), Indian (7%), White (9%), and Chinese (1%).

Relatively general model and the effective algorithm for calculation of the ice growth in shallow water in the salinity seas are proposed. This model considers the following factors: the dependence of seawater salinity on a changing salt portion rejected\nduring ice formation in shallow water, the dependence of phase transition temperature on the water salinity, a variation of the heat flux from water to a freezing front, as well as the impact of a snow cover height and the thermal conditions on its surface.\nAn algorithm for the numerical solution of model equations based on the front-tracking method is proposed. Results of computational experiments are illustrated by examples of\nsea ice growth calculations in shallow water also calculations of the ice salinity and the phase transition temperature at different points of time for different depths. The proposed\nmathematical model of the ice growth dynamic in shallow water is important for the Arctic shelf field development issues as well as the ice-hydrological and meteorological researches.

The clinical isolate Staphylococcus aureus is a major cause of illness such as pneumonia, meningitis etc. Failure to treatment with antibiotics due to resistant strains had emerged as a major problem. This study is aimed at evaluating the antibacterial activities of aqueous and ethanol extract of folkloric medicine (turmeric, ginger, garlic) against Staphylococcus aureus. Out of one thousand six hundred (1,600) sputum of clinically diagnosed pneumonia subjects of selected health institutions in the southern part of Nigeria. Sixteen (16) randomly selected bacterial culture isolates of Staphylococcus aureus were used. Cultural and biochemical tests were used to identify the test organisms. The antibacterial activities of the extracts were evaluated based on the inhibiting zone using agar well diffusion method and minimum inhibitory concentration. The aqueous extract of the plants at concentrations of ≤300mg/ml had no inhibitory effect against the test organisms. Ethanol extract of turmeric with inhibiting zone ranging from 4-14mm and average MIC of 30.37mg/ml was more effective and potent than both ginger and garlic with inhibiting zone ranging from 2-9mm, average MIC of 394.92mg/ml and 3-6mm, average MIC of 274.22mg/ml of ethanol extract against the test organisms respectively. One of the isolates (SAP82) was resistant to all extract except ethanol extract of turmeric. Rifampicin a positive control drug used for the study was significantly more effective than all plants extract used with a higher average zone of inhibition. This study therefore provides scientific justification for the use of herbs in ethno-medical practice in Nigeria.