Nuclear factor erythroid 2 – related factor 2 and its relationship with cellular response in nickel exposure: a systems biology analysis

Background Nickel and nickel-containing compounds (NCC) are known human carcinogens. However, the precise molecular mechanisms of nickel-induced malignant transformation remain unknown. Proposed mechanisms suggest that nickel and NCC may participate in the dual activation/inactivation of enzymatic pathways involved in cell defenses against oxidative damage, where Nuclear factor-erythroid 2 related factor 2 (Nrf2) plays a central role. Methods For assessing the potential role of proteins involved in the Nrf2-mediated response to nickel and NCC exposure, we designed an interactome network using the STITCH search engine version 5.0 and the STRING software 10.0. The major NCC-protein interactome (NCPI) generated was analyzed using the MCODE plugin, version 1.5.1 for the detection of interaction modules or subnetworks. Main centralities of the NCPI were determined with the CentiScape 2.2 plugin of Cytoscape 3.4.0 and main biological processes associated with each cluster were assessed using the BiNGO plugin of Cytoscape 3.4.0. Results Water-soluble NiSO4 and insoluble Ni3S2 were the most connected to proteins involved in the NCPI network. Nfr2 was detected as one of the most relevant proteins in the network, participating in several multifunctional protein complexes in clusters 1, 2, 3 and 5. Ontological analysis of cluster 3 revealed several processes related to unfolded protein response (UPR) and response to endoplasmic reticulum (ER) stress. Conclusions Cellular response to NCC exposure was very comparable, particularly concerning oxidative stress response, inflammation, cell cycle/proliferation, and apoptosis. In this cellular response, Nfr2 was highly centralized and participated in several multifunctional protein complexes, including several related to ER-stress. These results add evidence on the possible Ni2+ induced – ER stress mainly associated with insoluble NCC. In this scenario, we also show how protein degradation mediated by ubiquitination seems to play key roles in cellular responses to Ni.

Modular 9.0L and 4.5L Non-Road Spark-Ignited Engines for Power Generation

Following the successful commercial use of a 9.0L, V-8 automotive-derivative engine for stationary power generation, a new 4.5L, four-cylinder engine has been developed utilizing a modular family design approach. Substantial commonality of power cylinder components has been achieved including the complete power cylinder and cylinder head. This paper describes the design and development approach to the engine family. These spark-ignited engines are typically used for standby emergency power and demand response applications utilizing commercial grade natural gas or propane. Driving a synchronous electrical generator operating at 60 HZ or 50Hz, engine speeds are either 1800 rpm/3600 rpm or 1500 rpm/3000 rpm respectively, depending upon selection of either a 2-pole or 4-pole alternating current generator. Designed for stoichiometric combustion, the engine configurations can include naturally-aspirated, turbocharged or turbocharged and after-cooled versions. Depending upon end-use applications, exhaust emissions technology and regulatory compliance can be met solely through engine calibration or inclusion of a 3-way catalyst with active air-fuel ratio control. Since the 9.0L engine version was successfully introduced in 2012, significant efforts have been undertaken to achieve commonality of desired features between the existing veeengine and the future in-line versions, including optimization of performance characteristics in consideration of future power rating structures. Starting from 9.0L commercial introduction, the content herein specifically describes the development of the new 4.5L engine with regard to design and analysis.

Aerosol chemistry and particle growth events at an urban downwind site in North China Plain

The North China Plain (NCP) has experienced frequent severe haze pollution events in recent years. While extensive measurements have been made in megacities, aerosol sources, processes, and particle growth at urban downwind sites remain less understood. Here, an aerosol chemical speciation monitor and a scanning mobility particle sizer, along with a suite of collocated instruments, were deployed at the downwind site of Xingtai, a highly polluted city in the NCP, for real-time measurements of submicron aerosol (PM1) species and particle number size distributions during May and June 2016. The average mass concentration of PM1 was 30.5 (±19.4) µg m−3, which is significantly lower than that during wintertime. Organic aerosols (OAs) constituted the major fraction of PM1 (38 %), followed by sulfate (25 %) and nitrate (14 %). Positive matrix factorization with the multilinear engine version 2 showed that oxygenated OA (OOA) was the dominant species in OA throughout the study, on average accounting for 78 % of OA, while traffic and cooking emissions both accounted for 11 % of OA. Our results highlight that aerosol particles at the urban downwind site were highly aged and mainly from secondary formation. However, the diurnal cycle also illustrated the substantial influence of urban emissions on downwind sites, which are characterized by similar pronounced early morning peaks for most aerosol species. New particle formation and growth events were also frequently observed (58 % of the time) on both clean and polluted days. Particle growth rates varied from 1.2 to 4.9 nm h−1 and our results showed that sulfate and OOA played important roles in particle growth during clean periods, while OOA was more important than sulfate during polluted events. Further analyses showed that particle growth rates have no clear dependence on air mass trajectories.

DEVELOPMENT OF THE BRICAN TD100 SMALL UAS AND PAYLOAD TRIALS

The Brican TD100 is a high performance, small UAS designed and made in Brampton Ontario Canada. The concept was defined in late 2009 and it is designed for a maximum weight of 25 kg which is now the accepted cut-off defining small civil UASs. A very clean tractor propeller layout is used with a lightweight composite structure and a high aspect ratio wing to obtain good range and endurance. The design features and performance of the initial electrically powered version are discussed and progress with developing a multifuel engine version is described. The system includes features enabling operation beyond line of sight (BLOS) and the proving missions are described. The vehicle has been used for aerial photography and low cost mapping using a professional grade Nikon DSLR camera. For forest fire research a FLIR A65 IR camera was used, while for georeferenced mapping a new Applanix AP20 system was calibrated with the Nikon camera. The sorties to be described include forest fire research, wildlife photography of bowhead whales in the Arctic and surveys of endangered caribou in a remote area of Labrador, with all these applications including the DSLR camera.

Propulsion System Considerations for the Subsonic V/STOL

A representative subsonic V/STOL aircraft operating on a single mission has been used as a baseline to investigate the impact of various propulsion system tradeoffs. After establishing a cycle for the propulsion system and estimating V/STOL related installation penalties, parametric engine-aircraft-mission studies have been conducted. These studies have established takeoff gross weight benefits of up to 13 percent that may be obtained by appropriate selection of the core engine sizing location. Studies of two, three and four engine versions of the configuration have shown that three engine and four engine aircraft may have 20 percent lower weight than a two engine version, but this arises at the cost of significantly reduced hot section life.