Acute hemorrhage and death in calves following chlorophacinone exposure

Three calves were submitted to the Iowa State University Veterinary Diagnostic Laboratory for diagnostic evaluation following an abrupt increase in morbidity and mortality in a calf herd associated with epistaxis and widespread hemorrhage. Each of the submitted calves had moderate-to-severe hemorrhage within various tissues and body cavities, including the thymus, subcutaneous region of the neck, mediastinum, lungs, pericardial sac, heart, spleen, perirenal fat, urinary bladder, and skeletal muscle, including the diaphragm. An anticoagulant rodenticide screen was performed on the livers of each calf. Significant concentrations of chlorophacinone were detected at 4.2, 3.6, and 2.9 ppm in liver. Multiple piles and an open pail of white powdery material were present within the facility in which the calves were housed and were identified as the sources of chlorophacinone. Acute hemorrhage and death occurred in fourteen 1.5-mo-old, crossbred calves following ingestion of the vitamin K antagonist chlorophacinone.

Laser synthesis of a weakly agglomerated aluminium oxide nanopowder doped with terbium and ytterbium

This paper describes a method of femtosecond laser synthesis of nanoparticles of powdered aluminum oxide doped with terbium and ytterbium was developed. The formation of a plasma torch of nanoparticles of a powdery material is carried out as a result of ablation under the influence of a sharply focused beam of femtosecond laser radiation with an intensity of 108- 1010W/m2. The radiation source is the TETA-10 laser system. SEM images of the obtained nanopowders are presented. Spherical nanoparticles of narrow particle size distribution in the range from 5 to 15 nm was synthesized with the ability to control the size of nanoparticles by purposefully changing the parameters and characteristics of pulsed radiation in the treatment area. The design of a specialized high-voltage electrostatic precipitator up to 25 kV for capturing ablated nanoparticles in an electron cloud of increased concentration was developed.

Mechanically Stable β-TCP Structural Hybrid Scaffolds for Potential Bone Replacement

The authors report on the manufacturing of mechanically stable β-tricalcium phosphate (β-TCP) structural hybrid scaffolds via the combination of additive manufacturing (CerAM VPP) and Freeze Foaming for engineering a potential bone replacement. In the first step, load bearing support structures were designed via FE simulation and 3D printed by CerAM VPP. In the second step, structures were foamed-in with a porous and degradable calcium phosphate (CaP) ceramic that mimics porous spongiosa. For this purpose, Fraunhofer IKTS used a process known as Freeze Foaming, which allows the foaming of any powdery material and the foaming-in into near-net-shape structures. Using a joint heat treatment, both structural components fused to form a structural hybrid. This bone construct had a 25-fold increased compressive strength compared to the pure CaP Freeze Foam and excellent biocompatibility with human osteoblastic MG-63 cells when compared to a bone grafting Curasan material for benchmark.

Searching for biological feedstock material: 3D printing of wood particles from house borer and drywood termite frass

Frass (fine powdery refuse or fragile perforated wood produced by the activity of boring insects) of larvae of the European house borer (EHB) and of drywood termites was tested as a natural and novel feedstock for 3D-printing of wood-based materials. Small particles produced by the drywood termite Incisitermes marginipennis and the EHB Hylotrupes bajulus during feeding in construction timber, were used. Frass is a powdery material of particularly consistent quality that is essentially biologically processed wood mixed with debris of wood and faeces. The filigree-like particles flow easily permitting the build-up of wood-based structures in a layer wise fashion using the Binder Jetting printing process. The quality of powders produced by different insect species was compared along with the processing steps and properties of the printed parts. Drywood termite frass with a Hausner Ratio HR = 1.1 with ρBulk = 0.67 g/cm3 and ρTap = 0.74 g/cm3 was perfectly suited to deposition of uniformly packed layers in 3D printing. We suggest that a variety of naturally available feedstocks could be used in environmentally responsible approaches to scientific material sciences/additive manufacturing.

Searching for biological feedstock material: 3D printing of wood particles from house borer and drywood termite frass

Frass (fine powdery refuse or fragile perforated wood produced by the activity of boring insects) of larvae of the European house borer and of drywood termites was tested as a natural and novel feedstock for 3D-printing of wood-based materials. Small particles produced by the drywood termite Incisitermes marginipennis and the European house borer (EHB) Hylotrupes bajulus during feeding in construction timber, were used. Frass is a powdery material of particularly consistent quality that is essentially biologically processed wood mixed with debris of wood and faeces. The filigree-like particles flow easily permitting the build-up of wood-based structures in a layer wise fashion using the Binder Jetting printing process. The quality of powders produced by different insect species was compared along with the processing steps and properties of the printed parts. Drywood termite frass with a HR = 1.1 with ρBulk = 0.67 g.cm-3 and ρTap = 0.74 g.cm-3 was perfectly suited to deposition of uniformly packed layers in 3D printing. We suggest that a variety of naturally available feedstocks could be used in environmentally responsible approaches to scientific material sciences/additive manufacturing.

Blooming of Compounding Ingredients in Natural Rubber Compounds under Different Peroxide Loading

Rubber compounds normally shows blooming phenomena whereby a thin layer of powdery material or films and oils formed on the surface. These blooms are usually low molecular weight compounding ingredients such as curing agents, accelerator, processing aids and activators that migrated to the surface. Excessive blooming can degrade the vulcanized rubber and reduced its quality. It is therefore necessary to determine the compounding ingredients that bloomed in an effort to reduce the effect of blooming. This study was aimed at identifying the compounding ingredients that dominate the blooming process. Sulphur, paraffin wax and zinc diethyldithiocarbamate (ZDEC) with specific functions were added as compounding ingredients in natural rubber (SMR L). Dicumyl peroxide were added as the curing agent at several loadings. The rubber compounds were cured at 150oC in the presence of dicumyl peroxide as curing agent at several loadings. They were stored under room temperature for blooming to take place. Blooms were analysed using FTIR and EDX. EDX analysis detected the major element present in the blooms to be carbon at 53.5% abundance. Similarly, FTIR results produced high intensity of C-H band at 2916 cm-1 and 722 cm-1 which are due to stretching and bending vibration of C-H paraffinic. It was concluded that paraffin wax preceded sulphur and ZDEC in blooming of SMR L.

Paleoenvironmental considerations based on geochemistry and mineralogy of a Miocene lacustrine calcrete, southern Portugal

A lacustrine carbonate facies has been investigated in Middle Miocene successions of the western side of the Moura-Marmelar basin, Southern Portugal in order to evaluate paleoenvironments in which carbonates formed, by using geochemistry and mineralogy. The studied formation corresponds to a recent unearthed section of a calcrete with an homogeneous carbonate facies comprising fine, whitish, and powdery material, and the only detected difference is a slightly hardness decrease towards the top, as well as an increase of weathered rock fragments (schist). The calcrete is calcium rich, even some magnesium enrichment was observed at the middle level, which is differentiated by a general depletion of all chemical elements, particularly REE, in both the bulk and clay-size fraction. Regarding the mineralogy, calcite prevails, and dolomite is only present in the middle level of the calcrete, together with a smectite enrichment, suggesting changes to more alkaline and low drainage, lacustrine and arid to semi-arid conditions.