Urban form and planning in the information age: Lessons from literature

This paper focuses on the relationship between information and communication technologies (ICT) and urban form, and on urban planning response to spatial and economic consequences of ICT. It starts with literature-based review of how urban environments in the United States change with technological advances and explanations of the relationship between ICT and urban form. The paper also includes a discussion of the manner in which ICT impact is handled by urban planning. The literature review points to insufficient attention to the dynamics between ICT and urban planning and increasing gap between physical and economic development implications of ICT. It is the role of urban planners to balance the consideration of the physical and economic aspects against the prospects and opportunities offered by ICT.

Evaluation of the Biofilm Forming Capacities of Bacterial Isolates Recovered in Raw and Treated Effluent from Wastewater Treatment Plant of Ahmadu Bello University Zaria, Nigeria

Biofilm producing bacteria are associated with many recalcitrant infections and are highly resistant to antimicrobial agents, hence notoriously difficult to eradicate. This study aimed at determining the biofilm forming capacities of bacterial isolates recovered in the raw wastewater and treated effluent from Wastewater Treatment Plants of Ahmadu Bello University Zaria using Tube Method (TM) and Congo Red Agar (CRA) method; and from the results, among the isolates recovered from the raw wastewater, TM detected 62.5% isolates as positive and 37.5% as negative for biofilm production, CRA detected 37.5% isolates as positive and 62.5% as negative for biofilm production. TM also demonstrated to be more suitable in detecting biofilm producing bacterial isolates from the treated effluent were it detected 50% isolates as positive and 50% as negative. However, CRA detected only 12.5% isolates as positive and 87.5% as negative for biofilm production. We therefore, conclude that the TM is more efficient and reliable for detection of biofilm producing bacteria in the laboratory when compared to CRA method and can be recommended as one of the suitable standard screening method for the detection of biofilm producing bacteria in laboratories.Keywords: Biofilm; Bacteria; Congo red agar and Tube metho

Modelling the electromagnetic separation of non-metallic particles from liquid metal flowing through a two-stage multichannel

A two-stage multichannel was designed to increase the efficiency of separating non-metallic particles from liquid metal flowing through an alternating magnetic field. Numerical method was developed to calculate the particle concentration and separation efficiency of a zinc melt containing dross particles and verified by the experimental results. The distribution of particle concentration and axial fluid velocity changed significantly due to the added walls in the sub-channel, resulting in an abrupt increase in the residence time of the inner bulk melt with high particle concentrations and a remarkable increase in particle separation efficiency when flowing through the single-channel to sub-channels. A multistage and multichannel arrangement is hence recommended for further increase in the separation efficiency of an electromagnetic separator

Simple Metals at High Pressure

In this lecture we review high-pressure phase transition sequences exhibited by simple elements, looking at the examples of the main group I, II, IV, V, and VI elements. General trends are established by analyzing the changes in coordination number on compression. Experimentally found phase transitions and crystal structures are discussed with a brief description of the present theoretical picture.Comment: 22 pages, 4 figures, lecture notes for the lecture given at the Erice course on High-Pressure Crystallography in June 2009, Sicily, Ital

Differentiating patterns of violence in the family

The feasibility and prevalence of Reciprocal, Hierarchical and Paternal patterns of family aggression hypothesised by Dixon and Browne (2003) were explored within a sample of maltreating families. The psychological reports of 67 families referred to services for alleged child maltreatment that evidenced concurrent physical intimate partner violence and child maltreatment were investigated. Of these, 29 (43.3%) cases were characterised by hierarchical; 28 (41.8%) Reciprocal and 10 (14.9%) Paternal patterns. Significant differences in the form of child maltreatment perpetrated by mothers and fathers and parent dyads living in different patterns were found. In Hierarchical sub-patterns, fathers were significantly more likely to have been convicted for a violent and/or sexual offence than mothers and were significantly less likely to be biologically related to the child. The findings demonstrate the existence of the different patterns in a sample of families involved in the Child Care Protection process in England and Wales, supporting the utility of a holistic approach to understanding aggression in the family

Swabs to genomes: A comprehensive workflow

© 2015 Dunitz et al. The sequencing, assembly, and basic analysis of microbial genomes, once a painstaking and expensive undertaking, has become much easier for research labs with access to standard molecular biology and computational tools. However, there are a confusing variety of options available for DNA library preparation and sequencing, and inexperience with bioinformatics can pose a significant barrier to entry for many who may be interested in microbial genomics. The objective of the present study was to design, test, troubleshoot, and publish a simple, comprehensive workflow from the collection of an environmental sample (a swab) to a published microbial genome; empowering even a lab or classroom with limited resources and bioinformatics experience to performit

Direct electronic measurement of the spin Hall effect

The generation, manipulation and detection of spin-polarized electrons in nanostructures define the main challenges of spin-based electronics[1]. Amongst the different approaches for spin generation and manipulation, spin-orbit coupling, which couples the spin of an electron to its momentum, is attracting considerable interest. In a spin-orbit-coupled system, a nonzero spin-current is predicted in a direction perpendicular to the applied electric field, giving rise to a "spin Hall effect"[2-4]. Consistent with this effect, electrically-induced spin polarization was recently detected by optical techniques at the edges of a semiconductor channel[5] and in two-dimensional electron gases in semiconductor heterostructures[6,7]. Here we report electrical measurements of the spin-Hall effect in a diffusive metallic conductor, using a ferromagnetic electrode in combination with a tunnel barrier to inject a spin-polarized current. In our devices, we observe an induced voltage that results exclusively from the conversion of the injected spin current into charge imbalance through the spin Hall effect. Such a voltage is proportional to the component of the injected spins that is perpendicular to the plane defined by the spin current direction and the voltage probes. These experiments reveal opportunities for efficient spin detection without the need for magnetic materials, which could lead to useful spintronics devices that integrate information processing and data storage.Comment: 5 pages, 4 figures. Accepted for publication in Nature (pending format approval

Mycobacterium tuberculosis from chronic murine infections that grows in liquid but not on solid medium

BACKGROUND: Old, stationary cultures of Mycobacterium tuberculosis contain a majority of bacteria that can grow in broth cultures but cannot grow on solid medium plates. These may be in a non-replicating, dormant growth phase. We hypothesised that a similar population might be present in chronic, murine tuberculosis. METHODS: Estimates of the numbers of viable M. tuberculosis, strain H37Rv, in the spleens and lungs of mice in a 7-day acute infection and in a 10-month chronic infection were made by conventional plate counts and, as broth counts, by noting presence or absence of growth in serial replicate dilutions in liquid medium. RESULTS: Plate and broth counts in 6 mice gave similar mean values in the acute infection, 7 days after infection. However, the broth counts were much higher in 36 mice with a chronic infection at 10 months. Broth counts averaged 5.290 log(10 )cfu /organ from spleens and 5.523 log(10 )cfu/organ from lungs, while plate counts were 3.858 log(10 )cfu/organ from spleens and 3.662 log(10 )cfu/organ from lungs, indicating that the total bacterial population contained only 3.7% bacilli in spleens and 1.4% bacilli in lungs, capable of growth on plates. CONCLUSION: The proportion growing on plates might be a measure of the "dormancy" of the bacilli equally applicable to cultural and animal models

Assessing the impact of woody and agricultural biomass variability on its behaviour in torrefaction through Principal Component Analysis

The influence of biomass macromolecular composition on its behaviour in torrefaction was statistically assessed through Principal Component Analysis (PCA), both in terms of solid conversion kinetics and volatile species released, in function of the operating conditions. The experimental data obtained in the torrefaction of 14 woody and agricultural biomass samples at lab-scale was analysed. Main biomass macromolecular composition on cellulose, hemicelluloses and lignin was shown to acceptably represent biomass diversity, which can be complemented by the extractives and ash content. Similitudes were found in deciduous and coniferous wood families, respectively, while agricultural and herbaceous crops were shown as more heterogeneous, both in terms of characterization and behaviour in torrefaction. Cellulose, hemicelluloses and lignin content strongly influenced solid and volatile species yields in torrefaction, while biomass family exhibited a lower impact. Ash content in potassium, phosphorous and silicon did not show any influence on the extent of solid degradation through torrefaction. A lower variability was found in solid degradation profiles from woods, while agricultural crop behaviour was more heterogeneous. Different volatile species were released from biomass samples from the same family. Furthermore, different production profiles were found for volatile species chemically close, except for deciduous wood. These results indicate that, when modelling biomass torrefaction, solid mass loss can be represented by an exemplar of deciduous and coniferous wood, while several species would be required for the agricultural family. The variability of the volatile species release would require the consideration of several volatile species and several biomass samples per famil