Use of Java RMI on Mobile Devices for Peer to Peer Computing

In this paper, the use of Java RMI on mobile devices for peer-to-peer computing is presented. An overview of the commonly used distributed middleware systems are described by looking into remote procedure call (RPC) and object oriented middleware java remote method invocation (Java RMI). The differences between this middleware are equally detailed in this work. A review of some related literature was carried out and some of the features required for the proposed prototype were also extracted accordingly. This paper also provides an overview of peer-to-peer networking and some of the application areas linked to the platform implementation. Detailed design and implementation of the artifact for peer-to-peer network using Java 2 platform programming language were carried out. Finally, on the process of this research, three applications were developed and peered together to show that java RMI is a tool for peer-to-peer computing. Keywords: - Remote method invocation, Remote procedure call, Stub, Skeleton, Peer-to-Pee

Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era

Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country’s late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g−1), than black males (ME = 3.80 µg·g−1) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead

From cassava to gari: Mapping of quality characteristics and end-user preferences in Cameroon and Nigeria

User's preferences of cassava and cassava products along the value chain are supported by specific root quality characteristics that can be linked to root traits. Therefore, providing an evidence base of user preferred characteristics along the value chain, can help in the functional choice of cassava varieties. In this respect, the present paper presents the results from focus group discussions and individual interviews on user preferred quality characteristics of raw cassava roots and the derived product, gari, ‐ one of the major cassava products in Sub Saharan Africa ‐ in major production and consumption areas of Cameroon and Nigeria. Choice of cassava varieties for farming is mainly determined by the multiple end‐uses of the roots, their agricultural yield and the processing determinants of roots that support their major high‐quality characteristics: size, density, low water content, maturity, colour and safety. Processing of cassava roots into gari goes through different technological variants leading to a gari whose high‐quality characteristics are: dryness, colour, shiny/attractive appearance, uniform granules and taste. Eba, the major consumption form of gari in Cameroon and Nigeria is mainly characterized by its textural properties: smoothness, firmness, stickiness, elasticity, mouldability. Recommendations are made, suggesting that breeding will have to start evaluating cassava clones for brightness/shininess, as well as textural properties such as mouldability and elasticity of cassava food products, for the purpose of supporting decision‐making by breeders and the development of high‐throughput selection methods of cassava varieties. Women are identified as important beneficiaries of such initiatives giving their disadvantaged position and their prominent role in cassava processing and marketing of gari

Globally, songs and instrumental melodies are slower and higher and use more stable pitches than speech: A Registered Report

Both music and language are found in all known human societies, yet no studies have compared similarities and differences between song, speech, and instrumental music on a global scale. In this Registered Report, we analyzed two global datasets: (i) 300 annotated audio recordings representing matched sets of traditional songs, recited lyrics, conversational speech, and instrumental melodies from our 75 coauthors speaking 55 languages; and (ii) 418 previously published adult-directed song and speech recordings from 209 individuals speaking 16 languages. Of our six preregistered predictions, five were strongly supported: Relative to speech, songs use (i) higher pitch, (ii) slower temporal rate, and (iii) more stable pitches, while both songs and speech used similar (iv) pitch interval size and (v) timbral brightness. Exploratory analyses suggest that features vary along a “musi-linguistic” continuum when including instrumental melodies and recited lyrics. Our study provides strong empirical evidence of cross-cultural regularities in music and speech

The contibutions of soil properties to cassava yield parameters in Sub-Saharan Africa

The Collaborative Study of Cassava in Africa (COSCA) undertook cassava yield and soil fertility surveys in sub-Saharan Africa in 1991 with the objectives of obtaining average yields from farmers' fields and determining factors which could account for the yield differences across the various climate, altitude, population density and market access zones - the site selection factors considered in the study. In this analysis, the contributions of various soil properties determined from the fields were also obtained and evaluated. The cassava yield parameters considered were fresh root and shoot weight, harvest index and cassava stand density. The interaction between the site selection factors had a greater significant effect on the yield parameters than the individual factors. Whereas the effect of climate was not significant (P = 0.1), both climate x market access and population x market access interactions were highly significant (P  0.01) on root yield. The overall mean root yield was estimated as 13.1 t/ha. It was highest in the subhumid followed by nonhumid and lowland humid zones, and least in the highland humid zone. It was significantly (P  0.05) higher (13.6 t/ha) in the low altitude zones than in the mid (8.5 t/ha) altitude zones. The results of stepwise regression analysis showed that the total contribution of soil variables to root yield variations ranged from about 30% for the entire sub-region through 32% in the lowland and about 40% in nonhumid zones to more than 45% in the highland humid zones. The contribution of total sulphur to the total variations in root yield was consistently high in both the sub-region and across the climate zones compared to other soil variables evaluated. The overall contributions of the soil variables to shoot yield, harvest index and stand density were approximately 35%, 30% and 50%, respectively. Though the contributions of the soil properties to cassava performance confirmed that other factors are also important in cassava production, the significant roles of individual soil variables both in the sub-region and across the climate zones have been established. Keywords: cassava, soil properties, regression, subSaharan Africa> Agro-Science Vol. 6 (1) 2007: pp. 1-1