Sodium adsorption using activated alumina for application in the dairy industry

Basic activated alumina with negatively charged surface is considered as a potential adsorbent for a targeted molecule with positive polarity. Adsorption of sodium by basic activated alumina was investigated as a method for desalting dairy waste streams, in which sodium ion concentration averaged 600 mg/L. Sodium equilibrium and kinetic adsorption were investigated using basic activated alumina with synthetic brines. The results of equilibrium adsorption show that uptake of sodium by activated alumina is significantly higher when the pH is greater than 8 and increases as the pH of the brines increases until pH reaches around 10. The results of kinetic adsorption show that 90 hours were needed to reach equilibrium for sodium adsorption. Binding and diffusion processes are suggested to have taken place within the activated alumina.

Evaluation of heat stress indices using physiological comparisons in an alumina refinery in a sub-tropical climate

The production of alumina involves the use of a process known as the Bayer process. This method involves the digestion of raw bauxite in sodium hydroxide at temperatures around 250°C. The resultant pregnant liquor then goes through a number of filtering and precipitation processes to obtain the aluminium oxide crystals which are then calcined to obtain the final product. The plant is situated in a sub tropical climate in Northern Australia and this combined with the hot nature of the process results in a potential for heat related illnesses to develop. When assessing a work environment for heat stress a heat stress index is often employed as a guideline and to date the Wet Bulb Globe Temperature (WBGT) has been the recommended index. There have been concerns over the past that the WBGT is not suited to the Northern Australian climate and in fact studies in other countries have suggested this is the case. This study was undertaken in the alumina plant situated in Gladstone Queensland to assess if WBGT was in fact the most suitable index for use or if another was more applicable. To this end three indices, Wet Bulb Globe Temperature (WBGT), Heat Stress Index (HSI) and Required Sweat Rate (SWreq) were compared and assessed using physiological monitoring of heart rate and surrogate core temperature. A number of different jobs and locations around the plant were investigated utilising personal and environmental monitoring equipment. These results were then collated and analysed using a computer program written as part of the study for the manipulation of the environmental data . Physiological assessment was carried out using methods approved by international bodies such as National Institute for Occupational Safety & Health (NIOSH) and International Standards Organisation (ISO) and incorporated the use of a ‘Physiological Factor’ developed to enable the comparison of predicted allowable exposure times and strain on the individual. Results indicated that of the three indices tested, Required Sweat Rate was found to be the most suitable for the climate and in the environment of interest. The WBGT system was suitable in areas in the moderate temperature range (ie 28 to 32°C) but had some deficiencies above this temperature or where the relative humidity exceeded approximately 80%. It was however suitable as a first estimate or first line indicator. HSI over-estimated the physiological strain in situations of high temperatures, low air flows and exaggerated the benefit of artificial air flows on the worker in certain environments ie. fans.

Process for the production of ultrafine plate-like alumina particles

A process for producing plate-like alumina particles with a high aspect ratio is described. Nano-sized particles of an aluminium precursor compound, optionally formed by milling, are mixed with a sufficient volume fraction of a diluent and heat treated to form substantially discrete plate-like alpha alumina particles dispersed in the diluent. A mineraliser may be added to lower the effective melting point of the system. Substantially discrete plate-like particles may be formed without agitation when the heat treatment is conducted below the melting point of the diluent.

Thermal and mechanical properties of a dendritic hydroxyl-functional hyperbranched polymer and tetrafunctional epoxy resin blends

Blends of a tetrafunctional epoxy resin, tetraglycidyl- 4,40'-diaminodiphenylmethane (TGDDM), and a hydroxylfunctionalized hyperbranched polymer (HBP), aliphatic hyperbranched polyester Boltorn H40, were prepared using 3,3'-diaminodiphenyl sulfone (DDS) as curing agent. The phase behavior and morphology of the DDS-cured epoxy/HBP blends with HBP content up to 30 phr were investigated by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). The phase behavior and morphology of the DDS-cured epoxy/HBP blends were observed to be dependent on the blend composition. Blends with HBP content from 10 to 30 phr, show a particulate morphology where discrete HBP-rich particles are dispersed in the continuous cured epoxy-rich matrix. The cured blends with 15 and 20 phr exhibit a bimodal particle size distribution whereas the cured blend with 30 phr HBP demonstrates a monomodal particle size distribution. Mechanical measurements show that at a concentration range of 0–30 phr addition, the HBP is able to almost double the fracture toughness of the unmodified TGDDM epoxy resin. FTIR displays the formation of hydrogen bonding between the epoxy network and the HBP modifier.

Process for the production of ultrafine plate-like alumina particles

A process for producing plate-like alumina particles with a high aspect ratio is described. Nano-sized particles of an aluminium precursor compound, optionally formed by milling, are mixed with a sufficient volume fraction of a diluent and heat treated to form substantially discrete plate-like alpha alumina particles dispersed in the diluent. A mineraliser may be added to lower the effective melting point of the system. Substantially discrete plate-like particles may be formed without agitation when the heat treatment is conducted below the melting point of the diluent.

Source of Bet v 1 loaded inhalable particles from birch revealed

Allergenic proteins present in pollen grains, when inhaled, interact with the airways to cause an attack of asthma in susceptible humans. In one system, grass pollen grains rupture osmotically in rainfall, releasing allergen-containing inhalable particles into the atmosphere. In contrast, birch tree pollen grains do not rupture under these conditions, yet the major allergen, Bet v 1, has been detected in the atmosphere in inhalable particles of unknown origin. It is possible that Bet v 1 may diffuse from intact settled pollen grains and the allergenic material may again become airborne, interacting with settled fine particles from other sources prior to resuspension. This study investigates the mechanism for the release of birch pollen allergen-containing inhalable particles from pollen grains. We propose the hypothesis that (1) airborne birch pollen grains settle on nearby leaf surfaces; (2) then, following light rainfall, the grains germinate and, (3) later, pollen tubes burst, releasing inhalable particles carrying Bet v 1 into the atmospheric aerosol.   We used microscopic analyses of pollen behaviour following anther opening, a Burkard volumetric trap for pollen counts and a high volume air sampler with a two-stage cascade impactor for quantitative immunochemical analyses of Bet v 1. On dry days of high birch pollen count (48 grains/m3, 1.5 ng/m3 of Bet v 1), we found that the surfaces of birch leaves became coated with pollen. This ”pollen rain” is a source of secondary emission of allergens into the atmosphere. We observed that following light rainfall (<1 mm per day), about 80% of the birch pollen grains germinated, producing pollen tubes, especially in the sticky surface secretions of leaf glands. These pollen tubes may grow up to 300 μm in length prior to rupturing, each releasing about 400 starch granules coated with allergen molecules that may, after drying, be dispersed into the aerosol. On these days following light rainfall, the highest atmospheric levels of Bet v 1 (1.18 ng/m3) are associated with inhalable particles. Following heavy rainfall, both pollen and inhalable particles are washed from the atmosphere. Immunoprinting studies show that Bet v 1 is associated with starch granules rather than the smaller orbicules. Bet v 1 is present in the atmosphere in large particles, i.e. in particular pollen grains and in inhalable particles, i.e. in particular starch granules.

Females use multiple mating and genetically loaded sperm competition to target compatible genes

Individuals in socially monogamous species may participate in copulations outside of the pair bond, resulting in extra-pair offspring. Although males benefit from such extra-pair behavior if they produce more offspring, the adaptive function of infidelity to females remains elusive. Here we show that female participation in extra-pair copulations, combined with a genetically loaded process of sperm competition, enables female finches to target genes that are optimally compatible with their own to ensure fertility and optimize offspring viability. Such female behavior, along with the postcopulatory processes demonstrated here, may provide an adaptive function of female infidelity in socially monogamous animals.

Novel alginate-enclosed chitosan–calcium phosphate-loaded iron-saturated bovine lactoferrin nanocarriers for oral delivery in colon cancer therapy

Aim: To develop polymeric-ceramic nanocarriers (NCs) in order to achieve oral delivery of the anticancer neutraceutical iron-saturated bovine lactoferrin (Fe-bLf) protein.

Materials & methods: Fe-bLf or paclitaxel (Taxol®) were adsorbed onto calcium phosphate nanocores, enclosed in biodegradable polymers chitosan and alginate. The Fe-bLf or Taxol-loaded NCs indicated as AEC–CP–Fe-bLf or AEC–CP–Taxol NCs, respectively, were made by combination of ionic gelation and nanoprecipitation. Size distribution, morphology, internalization and release profiles of the NCs were studied along with evaluation of in vitro and in vivo anticancer activities and compared with paclitaxel.

Results: AEC–CP–Fe-bLf NCs obtained spherical morphology and showed enhanced endocytosis, transcytosis and anticancer activity in Caco-2 cells in vitro. AEC–CP–Fe-bLf NCs were supplemented in an AIN 93G diet and fed to mice in both prevention and treatment human xenograft colon cancer models. AEC–CP–Fe-bLf NCs were found to be highly significantly effective when given orally, as a pretreatment, 1 week before Caco-2 cell injections. None of the mice from the AEC–CP–Fe-bLf NC-fed group developed tumors or showed any signs of toxicity, while the mice fed the control AIN 93G diet showed normal tumor growth. Fe-bLf or Taxol, when given orally in a diet as nanoformulations post-tumor development, showed a significant regression in the tumor size with complete inhibition of tumor growth later, while intratumoral injection of Taxol just delayed the growth of tumors. The pharmacokinetic and bioavailability studies indicated that nanoformulated Fe-bLf was predominantly present on tumor cells compared to non-nanoformulated Fe-bLf. Fe-bLf-loaded NCs were found to help in absorption of iron and thus may have utility in enhancing the iron uptake during iron deficiency without interfering with the absorption of calcium.

Conclusion: With the promising results of our study, the future potential of NC-loaded Fe-bLf in chemoprevention and in the treatment of human colon cancer, deserves further investigation for translational research and preclinical studies of other malignancies.