Antimicrobial and Anticancer Properties of Synthetic Peptides Derived from the Wasp Parachartergus fraternus

Agelaia-MPI and protonectin are antimicrobial peptides isolated from the wasp Parachartergus fraternus that show antimicrobial and neuroactive activities. Previously, two analogues of these peptides, neuroVAL and protonectin-F, were designed to reduce nonspecific toxicity and improve potency. Here, the three-dimensional structures of neuroVAL, protonectin and protonectin-F were determined by using circular dichroism and NMR spectroscopy. Antibacterial, antifungal, cytotoxic and hemolytic activities were tested for the parent peptides and analogues. All peptides showed moderate antimicrobial activity against Gram-positive bacteria, with agelaia-MPI being the most active. Protonectin and protonectin-F were found to be toxic to cancerous and noncancerous cell lines. Internalization experiments revealed that these peptides accumulate inside both cell types. By contrast, neuroVAL was nontoxic to all tested cells and was able to enter cells without accumulating. In summary, neuroVAL has potential as a nontoxic cell-penetrating peptide, while protonectin-F needs further modification to realize its potential as an antitumor peptide.     

Trace element concentrations in the Pacific harbor seal (Phoca vitulina richardii) in central and northern California

To determine concentrations of trace elements (THg, MeHg, Se, and Pb) in tissues of the Pacific harbor seal (Phoca vitulina richardii), live (n=186) and dead seals (n=53) were sampled throughout central and northern California from March 2003 to January 2005. There were significant differences in THg concentrations in blood and hair based on age (p<0.001). Adult male harbor seals had greater THg concentrations in their hair than adult female harbor seals (p<0.003). THg concentrations in liver increased linearly with age and delta15N (p<0.001); whereas, MeHg concentrations in liver increased exponentially until approximately 5 years of age with an asymptote at 1.3 microg/g wet weight. MeHg expressed as a percentage of THg (%MeHg) was best described by a decay function (r2=0.796, p<0.001), decreasing to a minimum at 4 years of age. Hepatic Se increased with age and was in equimolar ratios with THg in adults; whereas, molar ratio of Se:THg in pups deviated from a 1:1 ratio. Significant differences among study locations in THg concentrations in blood and hair were not detected. Assessing the possible effect of sampling location on Hg concentrations, however, was confounded and limited by lack of equal sample sizes for basic age and sex cohorts, a common dilemma in pinniped research.     

Accounting for migration in regional occupational employment projections

Occupational employment projections are one of the primary products produced by state labor market information agencies to assist with state and regional job training and worker assistance programs. In theory, the information from occupational employment forecasts should improve both interregional and intertemporal labor market efficiency through better matching between training efforts and job openings. Until recently, the projections methodology was predominantly a demand-requirements approach that failed to incorporate important labor supply effects and interstate/interregional dependencies. Recent research has focused on improving the labor supply specification. This paper reports on one such effort to evaluate the importance of interstate occupational migration and to develop methods to incorporate migration into the existing projections methodology. Initial results indicate that the total number of estimated job openings by occupation have to be revised significantly upwards when migration is taken into account.     

An approach to mechanistic event recognition applied on monitoring organic matter depletion in SBRs

A fundamental practice in process engineering is monitoring the state dynamics of a system. Unfortunately, observability of some states is related to high costs, time, and efforts. The mechanistic event recognition (MER) aims to detect an event (defined as a change of the system with specific significance to the operation of the process) that cannot be directly observed but has some predictable effect on the dynamics of the systems. MER attempts to apply fault diagnosis techniques using mechanistic “recognition” models to describe the process. A systematic method for building recognition models using optimal experimental design tools is presented. As proof of concept, the MER approach to detect organic matter depletion in sequencing batch reactors, measuring only ammonia, dissolved oxygen, and nitroxides is applied. The event, that is, consumption of organic matter to a level below 50 gCOD/m³, was successfully detected even though microbial activity is known to continue after organic matter depletion. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3460–3472, 2014     

Body Odors of Parasitized Caterpillars Give Away the Presence of Parasitoid Larvae to Their Primary Hyperparasitoid Enemies

Foraging success of parasitoids depends on the utilization of reliable information on the presence of their often, inconspicuous hosts. These parasitic wasps use herbivore-induced plant volatiles (HIPVs) that provide reliable cues on host presence. However, host searching of hyperparasitoids, a group of parasitoids that parasitize the larvae and pupae of other parasitoids, is more constrained. Their hosts do not feed on plants, and often are even concealed inside the body of the herbivore host. Hyperparasitoids recently have been found to use HIPVs of plants damaged by herbivore hosts in which the parasitoid larvae develop. However, hyperparasitoids that search for these parasitoid larvae may be confronted with healthy and parasitized caterpillars on the same plant, further complicating their host location. In this study, we addressed whether the primary hyperparasitoid Baryscapus galactopus uses caterpillar body odors to discriminate between unparasitized herbivores and herbivores carrying larvae of parasitoid hosts. We show that the hyperparasitoids made faster first contact and spent a longer mounting time with parasitized caterpillars. Moreover, although the three parasitoid hosts conferred different fitness values for the development of B. galactopus, the hyperparasitoids showed similar behavioral responses to caterpillar hosts carrying different primary parasitoid hosts. In addition, a two-chamber olfactometer assay revealed that volatiles emitted by parasitized caterpillars were more attractive to the hyperparasitoids than those emitted by unparasitized caterpillars. Analysis of volatiles revealed that body odors of parasitized caterpillars differ from unparasitized caterpillars, allowing the hyperparasitoids to detect their parasitoid host.     

Hydromorphological,hydraulic and ecological effects of restored wood: findings and reflections from an academic partnership approach

Large wood (re)introduction can deliver multiple benefits in river restoration, but there is a dearth of the detailed and longer‐term post‐project monitoring and evaluation required for improving best practice. We present findings from an academic partnership approach to post‐project evaluation, based on successive MSc research projects on restored large wood in the Loddon catchment, UK. Field and modelling data reveal: (i) key differences in large wood features between restored and natural reaches; (ii) increased hydraulic retention and changes to mesohabitats associated with large wood; (iii) differences in macroinvertebrate community composition around large wood but a lack of site‐level effects; (iv) interactions between macrophytes and large wood that may be specific to restored reaches; (v) a need for further field and modelling studies to inform the accurate representation of large wood in hydraulic models. Some key challenges in partnership working are identified to aid planning and effectiveness of future collaborations.     

Bark as feedstock for dual fluidized bed gasifiers—Operability,efficiency, and economics

The demand for biofuels and biochemicals is expected to increase in the future, which will in turn increase the demand for biomass feedstock. Large gasification plants fueled with biomass feedstock are likely to be a key enabling technology in a resource‐efficient, bio‐based economy. Furthermore, the costs for producing biofuels and biochemicals in such plants could potentially be decreased by utilizing inexpensive low‐grade residual biomass as feedstock. This study investigates the usage of shredded tree bark as a feedstock for the production of biomethane in the GoBiGas demonstration plant in Gothenburg, Sweden, based on a 32 MW_th industrial dual fluidized bed gasification unit. The plant was operated with bark feedstock for 12 000 hours during the period 2014 to 2018. Data from the measurement campaign were processed using a stochastic approach to establish the plant's mass and energy balances, which were then compared with operation of the plant with wood pellets. For this comparison, an extrapolation algorithm was developed to predict plant performance using bark dried to the same moisture content as wood pellets, ie, 8%_w.b. Plant operation with bark feedstock was evaluated for operability, efficiency, and feedstock‐related cost. The gas quality achieved during the test period was similar to that obtained for operation with wood pellets. Furthermore, no significant ash sintering or agglomeration problems were observed more than 750 hours of operation. The calculated biomass‐to‐biomethane efficiency is 43% to 47% (lower heating value basis) for operation with wet bark. However, the predicted biomass‐to‐biomethane efficiency can be increased to 55%–65% for operation with bark feedstock dried to 8% moisture content, with corresponding feedstock costs in the range of 24.2 to 32.7 EUR/MWh; ie, a cost reduction of about 40% compared with wood pellets.     

A Method of Driving a Chopping Disc at Slow or Moderate Speeds

An essential part of the densitometer described by Mr. Neale is a chopping disc rotating at approximately 7 revolutions per second. Various methods of coupling the disc to a small electric motor were tried but none was satisfactory. The problem was finally solved by constructing an eddy current motor of which the disc itself formed the rotating element.