Synthetic Manganese Dioxide Production

Before World War I the United States procured all of its battery grade manganese dioxide from the Caucasus. Even at this time some experimentation was under way to produce this depolarizing substance synthetically and the experiments were successful to a large extent so that when the ore from the Caucasus was cut off, the necessary material was produced synthetically. The shortage was relieved when a deposit of manganese dioxide was discovered in Montana, which was superior to the ore from the Caucasus

Inducible resistance to maize streak virus

Maize streak virus (MSV), which causes maize streak disease (MSD), is the major viral pathogenic constraint on maize production in Africa. Type member of the Mastrevirus genus in the family Geminiviridae, MSV has a 2.7 kb, single-stranded circular DNA genome encoding a coat protein, movement protein, and the two replication-associated proteins Rep and RepA. While we have previously developed MSV-resistant transgenic maize lines constitutively expressing ‘‘dominant negative mutant’’ versions of the MSV Rep, the only transgenes we could use were those that caused no developmental defects during the regeneration of plants in tissue culture. A better transgene expression system would be an inducible one, where resistance-conferring transgenes are expressed only in MSV-infected cells. However, most known inducible transgene expression systems are hampered by background or ‘‘leaky’’ expression in the absence of the inducer. Here we describe an adaptation of the recently developed INPACT system to express MSV-derived resistance genes in cell culture. Split gene cassette constructs (SGCs) were developed containing three different transgenes in combination with three different promoter sequences. In each SGC, the transgene was split such that it would be translatable only in the presence of an infecting MSV’s replication associated protein. We used a quantitative real-time PCR assay to show that one of these SGCs (pSPLITrepIII-Rb-Ubi) inducibly inhibits MSV replication as efficiently as does a constitutively expressed transgene that has previously proven effective in protecting transgenic maize from MSV. In addition, in our cell-culture based assay pSPLITrepIII-Rb-Ubi inhibited replication of diverse MSV strains, and even, albeit to a lesser extent, of a different mastrevirus species. The application of this new technology to MSV resistance in maize could allow a better, more acceptable product

Angiographic Anatomy of External Iliac Arteries in the Sheep.

External iliac artery atherosclerotic disease and aneurism occur in man. For treatment, imaging is required to facilitate minimally invasive introduction and advancement of stents within the intended vessels. Sheep are commonly used to test and improve stents. However, little information is published regarding the angiographic anatomy of the iliac arteries in the ovine species. The objective of this study was to describe the angiographic anatomy of the iliac arteries in the sheep. Computed tomography (CT) angiography and gross anatomical dissection were performed in, respectively, 10 and 43 adult ewes. Diameters and lengths of the arteries were measured. In comparison with man, salient anatomical differences were identified in the sheep: (1) the absence of common iliac arteries, (2) the common trunk at the origin of internal iliac arteries and (3) the location of the bifurcation of the external iliac arteries into femoral arteries in the pelvis (not in the limb). External iliac arteries in this series of sheep were 86 mm long in average and had a mean diameter of 7.5 mm. Lengths of arteries are only slightly different between man and sheep, while diameters are rather similar. Therefore, the sheep model appears to be sufficiently similar to man to test stent properties. This study provides useful reference images and measures of lengths and diameters of relevant arteries that could be applied to research with ovine models

An ABM to support collective reflection on the evolution of mobility

International audienceTransport infrastructures play a large part in defining a smart, sustainable and resilient city. Planning transportation systems traditionally rely on well-known evolutions of roads or public transportation (roundabouts for security, etc.). Yet, infrastructures might also benefit from, or may have to adapt to, recent disruptive innovations concerning modalities, technologies and societal organization (autonomous cars, smart infrastructure, homeworking, etc.). However, innovative urban policies might either facilitate mobility and increase citizen well-being, or create negative side effects. Urban planning therefore requires the city to assess the impact of these disruptive innovations by using "what if?" prospective studies. However, cities are complex sociotechnical systems: dynamics of transportation are nonlinear, and even wise choices might lead to negative side effects (e.g. the improvements in road layout might decrease the number of accidents, but increase road use and therefore increase pollution). Unfortunately, even if urban planning models and methodologies are available for traditional modalities (car, bus, etc.), no tool, nor methodology, exists today to assess the potential impact of disruptive innovations, and how they can be progressively integrated into planning infrastructures. The SwITCh project aims at providing a tool for a participative reflection on the evolution of urban mobility in the next 30 years (horizon 2050). It aims to support decision-making for urban planning related to transport issues, by providing a participative simulation tool. The ambition of the project is not to produce a simulator that can predict what will happen from now to 2050 and to solve all the problems, but to help stakeholders (urban planners, citizens, etc.) enrich their reflections and build a shared project to improve transport infrastructures. The tool is based on an agent-based model (ABM) of citizens’ mobility, implemented on the GAMA platform, which simulates different scenarios of city/environment evolution (based on a combination of literature review and interviews with experts and stakeholders) and tests different strategies to face them. In this presentation, we will introduce the approach in order to illustrate four different scientific challenges: (I) the modeling of individual mobility choices by the agents, (II) the multi-level modeling of the city, (III) the design and exploration of different scenarios of mobility evolution, and (IV) the design of a methodology based on the proposed tool to support collective reflection

Schematic diagram of synthesised constructs, with restriction enzyme sites incorporated for subsequent cloning.

<p>A) pSPLIT<i>rep</i>^1-219Rb-35S containing “modules” that could be removed and replaced with other sequences by restriction digest. B) Illustration showing how the <i>rep</i>^1-219Rb- transgene was split at the first AGGC (nucleotides 155, 156, 157 and 158 with respect to the start codon). The exon 2, cloned at the 5′ terminus of the split gene cassette in A) therefore began with GC, and the exon 1, cloned at the 3′ terminus, ended in AG. C) The synthesised <i>rep</i>^III-Rb- (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105932#pone-0105932-g001" target="_blank">Fig. 1A</a> for the full-length gene product) exon 2, preceded by the 3′-terminal half of the syntron, flanked by <i>Swa</i>I and <i>Spe</i>I RE sites. The 3′-terminal syntron/<i>rep</i>^1-219Rb- exon 2 in pSPLIT<i>rep</i>^1-219Rb-35S was replaced by the 3′-terminal syntron/<i>rep</i>^III-Rb- exon 2 to create pSPLIT<i>rep</i>^III-Rb-35S. Exon 1 remained the same for both constructs since they share the same 5′-terminal 156 bp. Similarly, other modules were exchanged to create further constructs, such as the CaMV 35S promoter for the maize ubiquitin promoter etc (see text for details).</p

Vertical box-and-whisker plots summarising real-time PCR data on all constructs bombarded at a 5∶1 weight ratio with infectious clones of diverse MSV strains and another mastrevirus species.

<p>A) MSV-Kom. The plots were constructed as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105932#pone-0105932-g006" target="_blank">Figure 6</a>. The number of replicates (i.e. the number of bombarded samples) were as follows: pSK, 34; pSPLITGusUbi, 18; pSPLIT<i>rep</i>^1-219Rb-UbiΔI, 18; pSPLIT<i>rep</i>^1-219Rb-Ubi, 14; pSPLIT<i>rep</i>^III-Rb-Ubi, 8; p<i>rep</i>^1-219Rb-, 9; pMSV-<i>Pst</i>I, 11. Plots in B-C) were constructed as described for A), but this time either pSPLIT<i>rep</i>^III-Rb-Ubi or pSK were co-bombarded with infectious clones of: B) the MSV-B strain isolate VW; and C) the PanSV strain A isolate Kar. The number of replicates for B) were: pSK, 11; pSPLIT<i>rep</i>^III-Rb-Ubi, 14. The number of replicates for C) were: pSK, 16; pSPLIT<i>rep</i>^III-Rb-Ubi, 25. All real-time PCRs were performed on total DNA extracted from BMS cells four days post-bombardment.</p

Gus assays to test for cryptic splice sites in the MSV long intergenic region.

<p>A) Gus expression cassettes used in the assays. B) Expression of Gus from p35S-GSLIR²⁴¹ (test construct) as a ratio to p35S-GS (positive control construct), four days after bombardment. Each bar is an average of three replicates; error bars represent 95% confidence intervals. Negative = negative control (protein extract from a non-bombarded Black Mexican sweet sample).</p