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The effects of plant growth regulators on callus induction rate and regeneration of K. alvarezii explants was evaluated. K. alvarezii calluses were induced in vitro with kinetin (K), 6-benzylaminopurine (B), 1-naphtalene acetic acid (N) and spermine (S). After 30 days, K. alvarezii explants produced filamentous calluses and isolated crystalline filaments growing from the medullar region and from cortical cells at the cut edge. The plant growth regulators 1-naphtalene acetic acid (1 mg L −1 ) and 6-benzylaminopurine (1 mg L −1 ) and the 1-naphtalene acetic acid + kinetin + spermine (1, 1, 0.018 mg L −1 respectively) combination produced 85 to 129% more calluses, with significant differences versus the control ( p < 0.05). Spermine at 0.018 mg L −1 produced calluses in the apical, intercalary and basal regions of explants. Spermine also reduced callus induction time to 7 days, which is faster than previously reported induction times with other plant growth regulators. An airlift bioreactor was designed and characterized to micropropagate K. alvarezii calluses. The bioreactor had mixing times ranging from 4.6-10.3 s at T 90 and T 95 , which is shorter than those for the Fernbach (5.2-13.4 s) and balloon flasks (6.3-17.3 s). Mixing time standard deviations were smaller for the bioreactor (1.1-4.6) than for the Fernbach (9.3-13.6) and balloon flasks (5.5-15.8), suggesting an adequate flow regime within the bioreactor. The results are useful for improving callus induction in K. alvarezii and propagating microplantlets in an airlift bioreactor, and provide baseline data for macroalgal bioreactor culture.

Epiphytism in Gracilaria is a common phenomena observed in natural populations and under culture conditions. Generally, epiphytes are attached superficially to the surface of the host however, genera such as Polysiphonia spp. and Ceramium spp. can penetrate into the host tissue affecting its growth and hence productivity. The present paper aims to identify and quantify epiphyte abundance and characterise their attachment and penetration on the natural populations of Gracilaria cliftonii collected from Shoalwater Marine Park, Perth, Western Australia. G. cliftonii samples were collected monthly for 1 year and their epiphytes were identified. Histological studies of G. cliftonii were also performed on epiphyte attachment sites. Twenty-four species of macroalgae epiphytes were recorded, 21 belonging to Rhodophyta and 3 to Chlorophyta. Hypnea episcopalis and Polysiphonia forfex were the dominant (p<0.05) species during the sampling period. The maximum epiphytic load was observed in October (40%), however, the maximum diversity of epiphytes was recorded in September and February (n=14). Light and scanning electron microscopy studies of the epiphyte attachment sites revealed that P. forfex and Ceramium isogonum penetrated into the cortex and outer medulla of G. cliftonii, while Bryopsis plumosa and Laurencia clavata altered the cellular structure of the cell wall of G. cliftonii.

In order to find an industrial application for thin films of TiN and ZrN monolayers, as well as TiN/ZrN multilayers were deposited onto silicon (100) and AISI 5160 steel substrates by r.f. (13.56 MHz) multitarget magnetron sputtering from high-purity (99.5 %) Ti and (99.5%) Zr targets in an Ar (93%) / N 2 (7%) gas mixture. For their deposition, we applied a substrate bias voltage of -100 V and a target power of 350 W. The films were deposited at a pressure of 6x10 -3 mbar and a temperature of 250 o C. The structure, composition, morphology, and topography were characterized by, XRD, FTIR, SEM, AFM, and optical microscopy. Mechanical properties like hardness and elastic modulus were determined by Nanoindentation. Hardness and elastic modulus of the films increased proportionally to the number of bilayers. Finally, cutting tools were coated with 1, 2, 3, 4, 5, 6, 7, and 8 bilayers of TiN/ZrN. Cutting tests on paper blades were conducted. Increased cut quality performance was observed for cutting tools coated with 8 bilayers, as compared to uncoated tools. This work opens the possibility to use coated AISI 5160 as cutting tools for the paper industry, reducing the import of expensive high-quality tool steel.

Infection with nontyphoidal Salmonella is traditionally characterized by intestinal manifestations. However, extra-intestinal infections are known to occur, with purulent pericarditis associated with cardiac tamponade being rare. This case report is of a 57-year-old male with Crohn’s disease initiated on infliximab therapy two months prior to presentation. He presented with recurrent chest pain and a single occurrence of fever. A Computed Tomography (CT) scan of the chest revealed a pericardial effusion. An echocardiogram confirmed the presence of the fluid with tamponade physiology, requiring immediate surgical decompression. The pericardial fluid culture grew Salmonella enterica, despite the patient having only a single episode of fever, disproportionate to the severity of the infection. Conceivably, the lack of systemic symptoms may be attributed to recent infliximab therapy. Upon conducting a literature review, immunosuppressive factors seem to play a significant role in nontyphoid Salmonella enterica pericardial effusion presenting with cardiac tamponade.