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Elemental analysis of these medicinal plants was performed by employing Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced radio activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution High Purity Germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plant samples collected from different regions was studied and the biological effects of these elements on human beings are discussed. The study was also extended further to estimate the level of toxic elements like Cr, Cd, Ni, Pb and Hg in medicinal plants which arises due to environmental pollution. The results were discussed with careful reference to established role of essential and rare elements to the physiology and pathology of plant and human life.

The purpose of this paper is to review the novel application of surface plasmon resonance (SPR) in sensing heavy metal ions and the development of SPR to become an alternative heavy metal ions sensor.

The possible dangerous toxic effects of heavy metal ions are revealed in the short introduction. The existing conventional methods for sensing heavy metal ions and their drawbacks are also discussed. To overcome these drawbacks, SPR has been investigated from the basic principle to the potential alternative in sensing heavy metal ions.

Application of SPR in sensing heavy metal ions emerged a decade ago. A wide range of active layers or recognition elements (e.g. polymer, protein, nanoparticles) have been developed to combine with SPR. The detection limit, sensitivity and selectivity of SPR sensing in heavy metal ions have been improved from time to time, until the present.

This paper provides up-to-date and systematic information on SPR sensing for heavy metal ions. Different advancements on active layers or recognition molecules have been discussed in detail and arranged in the order of their chronological evolution. The present review may provide researchers with valuable information regarding novel heavy metal ions sensor using SPR and encourage them to take this area for further research and development.

The purpose of this paper is to investigate the psychosocial perception of harmattan dust on building openings, health and housekeeping to determine the influence of the dust on building occupants.

Population-representative survey data were collected from Maiduguri, Northeastern Nigeria, through physical administration of questionnaires by assessing several variables. Statistical package SPSS 16.0 was used for the data analysis, which is mainly descriptive analysis in frequencies, percentages and means together with a repeated Pearson’s chi-square analysis to identify the relationship between the factors and the significance testing.

The results show that majority (94.3%) experienced dust problem in harmattan season, and a larger part (76.6%) confirmed that the dust penetrates through doors and windows. Higher percentage (91.2%) noticed that the dust particles on their floor/furniture surfaces, and on an average, people clean their houses three times daily in harmattan season. Majority (80.5%) of the respondents smell dust in the harmattan season, and greater part (77.9%) experienced health challenges in this season, of which 12.8% confirmed harmattan dust aggravates their asthma, 13.6% confirmed it causes headache, 3.1% confirmed it exacerbated pneumonia, 58.5% confirmed it causes coughing, 3.5% confirmed catarrh, 2.3% confirmed nasal/respiratory congestion, sneezing and bronchitis and 6.2% experienced eye problems. Moreover, the results indicate that number/types of openings in a building are significantly associated with factors including smelling dust in the harmattan season and health problem experienced because of dust indoors. The number of times people clean their homes/workplaces is significantly related to important variables such as experiencing dust problem in harmattan season and number/type of openings in a building. The results further established that the health problem experienced by people is significantly related to important variables including dust problem experienced in the harmattan season and type of openings in a room.

Harmattan dust is a serious challenge to health and well-being of building occupants in the study area. The built environment professionals need to optimize building openings for effective dust control indoors.

The purpose of this paper is to investigate the selenium content in seven different infant starting formulae, eight different follow‐on formulae and in 15 different special infant formulae, from various producers, all commercially available in Slovenia.

Each product was taken in various lots during a three‐year period (from 2004 to 2006). For the determination of selenium content in different infant formulae the method of hydride generation atomic fluorescence spectrometry (HG‐AFS) was optimised. The reliability of the method was checked by the independent method of radiochemical neutron activation analysis (RNAA).

The values for different infant formulae ranged from 20.9 to 207.9 ng/g powder. The paper compared the values obtained with the declared values where possible. The average concentration showed insufficient agreement with the declared value in four out of 30 cases. The paper also found significant variation in selenium content between formulae in the same group. In some cases, large variations between different lots of the same product were found.

Calculated from our results, from infant formulae babies obtain from 2.4 to 24.0 ug Se per day, showing insufficient agreement with recommended daily intakes published by D_A_CH and by WHO. Since information on the endogenous Se levels of infant formulae is largely lacking, therefore there is still need for stricter quality control of the selenium content in infant formulae.

The discipline of Human Factors is concerned to contribute to the Safety and Effectiveness of systems by the integration of scientific knowledge about human beings into total system design. The aim of this specialised two‐week course is to provide, for senior personnel in aviation, a review of human factors in relation to the design and operation of transport aircraft.

It often becomes necessary to analyse a grease for a variety of reasons:

Heavy metals constitute one of the most hazardous substances that could be accumulated in biota coming from human activities such as agricultural and industrial wastes. This paper aims to study the levels of some of the most common heavy metals in muscles of the fish caught in the Karun River (Ahvaz, Iran) and to assess the health risks associated with their consumption.

In present study, the concentrations of three heavy metals (Pb, Cd and Cu) in the muscle of highly consumed fish species Ctenopharyngodon Idella (Cyprinidae) collected from three selected markets (Khoram Kooshk, Ahvaz-e Qadim and Padad Shahr; total number of samples was 45) in Ahvaz city and human health risk associated with their consumption were detected by Inductively Coupled Plasma Mass Spectrometry (ICP-MS).

The results indicated that the highest and lowest accumulated metal concentrations were related to Cu (20.36 ± 0.84) and Cd (0.53 ± 0.02), respectively. In addition, the mean difference for Pb and Cu across two pairwise of sampling sites were significant (Ahvaz-e Qadim and Khoram Kooshk, P for Pb = 0.025, P for Cu = 0.033; Ahvaz-e Qadim and Padad Shahr, p for Pb = 0.018, p for Cu = 0.039). The estimated daily intake of all metals in muscles of fish in this study were below the legal limit, and mean differences were not statistically significant among the sampling sites, except for Cu (Ahvaz-e Qadim and Khoram Kooshk, p = 0.048; Ahvaz-e Qadim and Padad Shahr, p = 0.041). Target hazard quotient values were also all below 1.

It can be concluded that the fishes from Ahvaz city markets are comparatively clean and do not constitute a risk for human health.

Water absorption is a serious problem in all polymeric materials, including the glass fibre‐epoxide resin laminates used in printed circuit board manufacture. This paper describes experiments to determine the level of water absorption in these materials under different conditions of relative humidity and temperature using thermogravimetric analysis.