Hot topic: Brown marmorated stink bug odor compounds do not transfer into milk by feeding bug-contaminated corn silage to lactating dairy cattle

Brown marmorated stink bug (BMSB; Halyomorpha halys) is an emerging invasive species of grave concern to agriculture as a polyphagous plant pest with potential negative effects on the dairy industry. The purpose of this study was to determine the risk of including BMSB-contaminated silage in lactating dairy cow rations. First, 6 dairies, either highly infested (n = 3; 30 to 100 bugs per stalk) or not infested (n = 3), were sampled to assess the prevalence of bug secretion compounds tridecane (major component) and E-2-decenal (stink odor component) in silage and milk. Second, using wild BMSB, a mini-silo dose-response experiment (adding 100, 50, 25, 10, and 1 freshly crushed bugs/0.5 kg of chopped corn) was conducted to assess the effect of ensiling on BMSB stink odor compounds. Finally, synthetic BMSB stink odor compounds (10 g of tridecane and 5 g of E-2-decenal) were ruminally infused twice daily over 3 d, and samples of milk, urine, and rumen fluid were collected to evaluate disposition. Bug stink odor compounds were sampled by solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). Milk production and feed composition were unaffected when BMSB-contaminated silage was fed. Moreover, no E-2-decenal was detected in silage or milk (detection threshold = 0.00125 μg/mL). The dose-response of tridecane in mini-silo samples exhibited a linear relationship (R² = 0.78) with the amount of BMSB added; however, E-2-decenal was completely decomposed and undetectable in spiked mini-silos after ensiling. Both synthetic secretion compounds infused into rumen were undetectable in all milk and urine samples. E-2-Decenal was not detectable in rumen fluid, whereas tridecane was detected only at 15 min postinfusion but not present thereafter. Feed intake was unaffected by infusion treatment and BMSB secretion compounds (E-2-decenal and tridecane) were not observed in milk. E-2-Decenal and tridecane from the metathoracic gland of BMSB are not able to contaminate milk either due to the ensiling process or because of metabolism within the rumen. Concern over BMSB stink odor compounds contaminating the fluid milk supply, even on highly infested farms, is not warranted.     

Separation of Radioactive Elements from Ethiopian Kenticha Pegmatite Ore by Hydrometallurgical Methods

The leaching and extraction behavior of uranium and thorium from a high-grade Ethiopian pegmatite ore in a mixture of hydrofluoric acid and sulfuric acid has been investigated. The effects of variables such as the temperature, particle size, acid concentration, and leaching time were studied. The leaching efficiency of uranium increased with increasing temperature to 150°C, at which 96% removal of uranium was achieved. Particles in the size range of ??100?+?75 μm resulted in the highest leaching of uranium, while formation of a colloidal suspension was observed when using a fine particle size fraction (??75 μm). The dissolution of uranium increased with increasing leaching time. No significant systematic dependence of the leachability of thorium on the above variables was observed. Optimum extraction of uranium and thorium using D₂EHPA was obtained when using aqueous/organic phase volume ratio of 1:1, solvent concentration of 0.3 M, and contact time of 20 min.     

Iron oxide induced bagasse nanoparticles for the sequestration of Cr6+ ions from tannery effluent using a modified batch reactor

The emphasis of the present study is to investigate the potential of magnetic iron oxide nanoparticles synthesized using bagasse from sugarcane (M‐NIOB). M‐NIOB was infused onto the modified batch reactor (M‐BR) stirrers using mesh structures for the adsorption of Cr⁶⁺ contained in effluent from the leather industry. M‐NIOB exhibited supermagnetic properties under an external magnetic field with a saturation magnetization value of 9.192 emu/g at room temperature. M‐NIOB nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, vibrating sample magnetometer, and Brunauer–Emmett–Teller analysis. The size of the M‐NIOB particles ranged from 50 to 200 nm. The most favorable time, pH, and temperature for the application of M‐NIOB to Cr⁶⁺ removal from tannery effluent was found to be 180 min, 5, and 318 K, respectively. M‐NIOB adsorbent performed its best at an adsorbent dosage of 800 mg/150 mL with a particle size of 150 nm. Kinetic and thermodynamic studies have been conducted. The applicability of various adsorption models for the Cr⁶⁺ adsorption data was tested. Moreover, the desorption studies carried out at 60 °C proved the capability of M‐NIOB for regeneration and reuse. Hence, M‐NIOB could be potentially applied for the treatment of effluent that has Cr⁶⁺ as a major constituent. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46683.     

Numerical validation of viscoelastic responses of a pavement structure in a full-scale accelerated pavement test

This paper demonstrates the application of a generalised layered linear viscoelastic (LVE) analysis for estimating the structural response of flexible pavements. A comparison of the direct layered viscoelastic responses with approximate solutions based on the linear elastic (LE) and LVE collocation methods was also carried out. The different approaches were implemented by extending a layered elastic program with an improved computational performance. The LE and LVE collocation methods were further extended for analysis of pavements under moving loads. The methods were illustrated by analysing a pavement structure subjected to moving wheel loads of 30, 50, 60 and 80 kN using a Heavy Vehicle Simulator (HVS). The various responses (stresses and strains) in the pavement, at pavement temperatures of 0, 10 and 20°C, were measured using various types of sensors installed in the structure. It was shown that the approximated LVE solution based on the LE collocation method agreed very well with the measurements and is computationally the least expensive.