An Evaluation of Boar Spermatozoa as a Biosensor for the Detection of Sublethal and Lethal Toxicity.

A novel, objective, and rapid computed motility inhibition (CMI) assay was developed to identify and assess sublethal injury in toxin-exposed boar spermatozoa and compared with a subjective visual motility inhibition (VMI) assay. The CMI values were calculated from digital micrographic videos using a custom MATLAB script by contrasting the motility index values of each experiment with those of the background and control experiments. Following a comparison of the CMI and VMI assays results, it was determined that their agreement depended on the shape of the dose-response curve.

Anomalous-Diffusion-Assisted Brightness in White Cellulose Nanofibril Membranes.

The understanding of the interaction between light and complex, random structures is the key for designing and tailoring the optical appearance and performance of many materials that surround us, ranging from everyday consumer products, such as those for personal care, paints, and paper, to light diffusers used in the LED-lamps and solar cells. Here, it is demonstrated that the light transport in membranes of pure cellulose nanofibrils (CNFs) can be controlled to achieve bright whiteness in structures only a few micrometers thick. This is in contrast to other materials, such as paper, which require hundreds of micrometers to achieve a comparable appearance.

Aligning cellulose nanofibril dispersions for tougher fibers.

Nanocomposite materials made from cellulose show a great potential as future high-performance and sustainable materials. We show how high aspect ratio cellulose nanofibrils can be efficiently aligned in extrusion to fibers, leading to increased modulus of toughness (area under the stress-strain curve), Young's modulus, and yield strength by increasing the extrusion capillary length, decreasing its diameter, and increasing the flow rate. The materials showed significant property combinations, manifesting as high modulus of toughness (~28-31 MJ/m) vs.

Interfacial Polyelectrolyte Complex Spinning of Cellulose Nanofibrils for Advanced Bicomponent Fibers.

Fiber spinning of anionic TEMPO-oxidized cellulose (TOCN) nanofibrils with polycations by interfacial polyelectrolyte complexation is demonstrated. The formed fibers were mostly composed of cellulose nanofibrils and the polycations were a minor constituent, leading to yield and ultimate strengths of ca. 100 MPa and ca.

Water-resistant, transparent hybrid nanopaper by physical cross-linking with chitosan.

One of the major, but often overlooked, challenges toward high end applications of nanocelluloses is to maintain their high mechanical properties under hydrated or even fully wet conditions. As such, permanent covalent cross-linking or surface hydrophobization are viable approaches, however, the former may hamper processability and the latter may have adverse effect on interfibrillar bonding and resulting material strength. Here we show a concept based on physical cross-linking of cellulose nanofibers (CNF, also denoted as microfibrillated cellulose, MFC, and, nanofibrillated cellulose, NFC) with chitosan for the aqueous preparation of films showing high mechanical strength in the wet state.