A Laboratory Infection of Alfalfa Weevil, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae), Larvae With the Fungal Pathogen \u3ci\u3eZoophthora Phytonomi\u3c/i\u3e (Zygomycetes: Entomophthoraceae)

Larvae of the alfalfa weevil, Hypera postica, were infected by an in vitro colony of Zoophthora phytonomi. Two spore types (infective conidia, and resting spores) were produced from infection trials. The spore type produced may be influenced by the physiological state of the larvae. Trials using field collected larvae which would produce diapausing adults formed both conidia and resting spores. Trials using larvae from a nondiapausing colony, however, formed only resting spores

Disease as a Larval Mortality Factor in Alfalfa Weevil, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae) Populations in Illinois

During the 1974 growing season, larvae of the alfalfa weevil, Hypera postica (Gyllenhal), were examined for pathogens. Three larvae out of 715 examined were infected with a microsporidium. This infection was present in both Washington and Mason counties in Illinois

Wind and Windblown Sand Damage to Pearl Millet

Pearl millet [Pennisetum glaucum (L.) R. Br.] is grown worldwide in areas affected by wind erosion, but no data on associated damage to millet are available. Laboratory wind tunnel experiments were conducted to determine the kind and extent of damage to millet caused by wind, sandblasting, and burial. In Exp. 1, millet was exposed for 15 min to wind (8, 11, or 14 m s−1) or wind + sand (8.3, 25.0, or 41.7 g m−1 s−1 sand abrader flux) at 8 and/or 16 d after emergence (DAE). Viable leaf area, leaf net photosynthesis, and NO3 content were measured through 21 DAE and dry matter production through 57 DAE. In Exp. 2, millet was seeded as three single seeds or in tufts, exposed to 25 g m−1 s−1 sand flux for 15 min at the 1-, 2-, or 3-leaf stage, and then manually covered by 15 mm sand. Survival was monitored weekly; dry matter was determined 70 DAE. In Exp. 1, survival was uniformly 100%. Wind alone or low sand flux had no effect on viable leaf area. High sand flux decreased viable leaf area by 74% at 2 d after the 8-DAE exposure and 42% at 5 d after the 16-DAE exposure. Photosynthesis of the remaining leaf area was reduced up to 88% immediately after exposure compared with the control, and NO3 content of sandblasted millet was increased up to six times. Dry weight was reduced 40% at 21 DAE by the highest sand flux, but 9.7% at 57 DAE. In Exp. 2, burial decreased millet survival and dry weight. Buried tufts had a higher survival rate and 35% more dry weight than buried single plants. Millet buried at the 1-leaf stage had 28% higher survival than plants treated later. Sandblasting reduced dry matter of buried millet only. Regression analyses between calculated total kinetic effects and growth parameters showed low r2 values. Millet can survive short-term sandblasting at any growth stage, but growth is reduced by strong sand flux, a sequence of wind erosion events during early growth, or by combinations of abrasion with burial by blown sand

Fe limitation decreases transcriptional regulation over the diel cycle in the model diatom Thalassiosira pseudonana.

Iron (Fe) is an important growth factor for diatoms and its availability is further restricted by changes in the carbonate chemistry of seawater. We investigated the physiological attributes and transcriptional profiles of the diatom Thalassiosira pseudonana grown on a day: night cycle under different CO2/pH and iron concentrations, that in combination generated available iron (Fe\u27) concentrations of 1160, 233, 58 and 12 pM. We found the light-dark conditions to be the main driver of transcriptional patterns, followed by Fe\u27 concentration and CO2 availability, respectively. At the highest Fe\u27 (1160 pM), 55% of the transcribed genes were differentially expressed between day and night, whereas at the lowest Fe\u27 (12 pM), only 28% of the transcribed genes displayed comparable patterns. While Fe limitation disrupts the diel expression patterns for genes in most central metabolism pathways, the diel expression of light- signaling molecules and glycolytic genes was relatively robust in response to reduced Fe\u27. Moreover, we identified a non-canonical splicing of transcripts encoding triose-phosphate isomerase, a key-enzyme of glycolysis, generating transcript isoforms that would encode proteins with and without an active site. Transcripts that encoded an active enzyme maintained a diel expression at low Fe\u27, while transcripts that encoded the non-active enzyme lost the diel expression. This work illustrates the interplay between nutrient limitation and transcriptional regulation over the diel cycle. Considering that future ocean conditions will reduce the availability of Fe in many parts of the oceans, our work identifies some of the regulatory mechanisms that may shape future ecological communities

Characterizing Workload of Web Applications on Virtualized Servers

With the ever increasing demands of cloud computing services, planning and management of cloud resources has become a more and more important issue which directed affects the resource utilization and SLA and customer satisfaction. But before any management strategy is made, a good understanding of applications' workload in virtualized environment is the basic fact and principle to the resource management methods. Unfortunately, little work has been focused on this area. Lack of raw data could be one reason; another reason is that people still use the traditional models or methods shared under non-virtualized environment. The study of applications' workload in virtualized environment should take on some of its peculiar features comparing to the non-virtualized environment. In this paper, we are open to analyze the workload demands that reflect applications' behavior and the impact of virtualization. The results are obtained from an experimental cloud testbed running web applications, specifically the RUBiS benchmark application. We profile the workload dynamics on both virtualized and non-virtualized environments and compare the findings. The experimental results are valuable for us to estimate the performance of applications on computer architectures, to predict SLA compliance or violation based on the projected application workload and to guide the decision making to support applications with the right hardware.Comment: 8 pages, 8 figures, The Fourth Workshop on Big Data Benchmarks, Performance Optimization, and Emerging Hardware in conjunction with the 19th ACM International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS-2014), Salt Lake City, Utah, USA, March 1-5, 201

Phosphate transporters in marine phytoplankton and their viruses: Cross-domain commonalities in viral-host gene exchanges

Phosphate (PO 4) is an important limiting nutrient in marine environments. Marine cyanobacteria scavenge PO 4 using the high-affinity periplasmic phosphate binding protein PstS. The pstS gene has recently been identified in genomes of cyanobacterial viruses as well. Here, we analyse genes encoding transporters in genomes from viruses that infect eukaryotic phytoplankton. We identified inorganic PO 4 transporter-encoding genes from the PHO4 superfamily in several virus genomes, along with other transporter-encoding genes. Homologues of the viral pho4 genes were also identified in genome sequences from the genera that these viruses infect. Genome sequences were available from host genera of all the phytoplankton viruses analysed except the host genus Bathycoccus. Pho4 was recovered from Bathycoccus by sequencing a targeted metagenome from an uncultured Atlantic Ocean population. Phylogenetic reconstruction showed that pho4 genes from pelagophytes, haptophytes and infecting viruses were more closely related to homologues in prasinophytes than to those in what, at the species level, are considered to be closer relatives (e.g. diatoms). We also identified PHO4 superfamily members in ocean metagenomes, including new metagenomes from the Pacific Ocean. The environmental sequences grouped with pelagophytes, haptophytes, prasinophytes and viruses as well as bacteria. The analyses suggest that multiple independent pho4 gene transfer events have occurred between marine viruses and both eukaryotic and bacterial hosts. Additionally, pho4 genes were identified in available genomes from viruses that infect marine eukaryotes but not those that infect terrestrial hosts. Commonalities in marine host-virus gene exchanges indicate that manipulation of host-PO 4 uptake is an important adaptation for viral proliferation in marine systems. Our findings suggest that PO 4-availability may not serve as a simple bottom-up control of marine phytoplankton. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd

Southern theories in ICT4D

This paper suggests that the dominance of northern research paradigms in ICT4D may be viewed as a continuation of colonial sway over the endeavors of the global South. The notion of Southern Theory - as introduced in the work of Raewyn Connell, the Comaroffs, and others - may be a route by which re-searchers in the global South can reclaim the intellectual territory of ICT4D, with indigenous and regional research paradigms and theories rather than those simply absorbed from the global North

Insights into the regulation of DMSP synthesis in the diatom Thalassiosira pseudonana through APR activity, proteomics and gene expression analyses on cells acclimating to changes in salinity, light and nitrogen

Despite the importance of dimethylsulphoniopropionate (DMSP) in the global sulphur cycle and climate regulation, the biological pathways underpinning its synthesis in marine phytoplankton remain poorly understood. The intracellular concentration of DMSP increases with increased salinity, increased light intensity and nitrogen starvation in the diatom Thalassiosira pseudonana. We used these conditions to investigate DMSP synthesis at the cellular level via analysis of enzyme activity, gene expression and proteome comparison. The activity of the key sulphur assimilatory enzyme, adenosine 5′- phosphosulphate reductase was not coordinated with increasing intracellular DMSP concentration. Under all three treatments coordination in the expression of sulphur assimilation genes was limited to increases in sulphite reductase transcripts. Similarly, proteomic 2D gel analysis only revealed an increase in phosphoenolpyruvate carboxylase following increases in DMSP concentration. Our findings suggest that increased sulphur assimilation might not be required for increased DMSP synthesis, instead the availability of carbon and nitrogen substrates may be important in the regulation of this pathway. This contrasts with the regulation of sulphur metabolism in higher plants, which generally involves upregulation of several sulphur assimilatory enzymes. In T. pseudonana changes relating to sulphur metabolism were specific to the individual treatments and, given that little coordination was seen in transcript and protein responses across the three growth conditions, different patterns of regulation might be responsible for the increase in DMSP concentration seen under each treatment