Creating Culturally Relevant Instructional Materials: A Swaziland Case Study

In the field of English language learning, research proves that culturally relevant reading materials improve students’ language acquisition, learning motivation, self-esteem, and identity formation. Since English is the language of instruction in many distant countries, such as Swaziland, even when English is not the native language of those countries, how can native English speakers most easily produce and expand the reach of culturally relevant materials for foreign settings that require English materials? In a study involving undergraduate university students, the researchers investigate the extent to which individuals recognize and demonstrate the importance of cultural context and relevance when creating their own books for Swaziland students. From the study, it is clear that the focus must shift from simple book production and donation to first gaining a deeper understanding of the relationship between the learners’ lived realities and the cultural content depicted in the materials. The researchers conclude that five distinct characteristics should be present in instructional material in order to increase the engagement, language acquisition, and self-worth of the English Language Learner

An additive model to predict the rheological and mechanical properties of polypropylene blends made by virgin and reprocessed components

In this work, an additive model for the prediction of the rheological and mechanical properties of monopolymer blends made by virgin and reprocessed components is proposed. A polypropylene sample has been reprocessed more times in an extruder and monopolymer blends have been prepared by simulating an industrial process. The scraps are exposed to regrinding and are melt reprocessed before mixing with the virgin polymer. The reprocessed polymer is, then, subjected to some thermomechanical degradation. Rheological and mechanical experimental data have been compared with the theoretical predictions. The results obtained showed that the values of this simple additive model are a very good fit for the experimental values of both rheological and mechanical properties

First case of Mediterranean spotted fever-associated rhabdomyolysis leading to fatal acute renal failure and encephalitis

Mediterranean spotted fever (MSF) is a tick-borne zoonosis caused by Rickettsia conorii. In Italy, about 400 cases are reported every year and nearly half of them occur in Sicily, which is one of the most endemic regions. Although MSF is mostly a self-limited disease characterized by fever, skin rash, and a dark eschar at the site of the tick bite called a 'tache noire', serious complications are described, mainly in adult patients. Nevertheless, severe forms of the disease with major morbidity and a higher mortality risk have been described. We report a fatal case of MSF complicated by rhabdomyolysis, acute renal failure, and encephalitis in an elderly woman

Influence of a biodegradable contaminant on the mechanical recycling of a low-density polyethylene sample

Mechanical recycling of oil-derived polymers is certainly our best option to reduce pollution, save raw materials, and protect ourselves and the environment from the adverse effects of waste disposal. However, the presence of contaminants, including other types of plastics, that are mixed in during the recycling collection process or during the mechanical waste sorting stage could adversely affect the quality of the recycled product, leading to the recycling of a poor-quality secondary material. In this work, the influence of a biodegradable contaminant on the mechanical recycling of a low-density polyethylene (LDPE) sample was investigated by rheological (shear and non-isothermal elongation) and mechanical analyses. The results showed that 2% of the contaminant is able to influence the rheological, shear, and isothermal elongation properties of recycled LDPE, while the results of the mechanical tests showed that after one extrusion cycle, the main tensile properties were not significantly affected by the presence of the contaminant, but after only two cycles of extrusions, some significant reduction in the final properties began to appear. In short, the presence of 2% of a biodegradable co-polyester in a LDPE matrix gives rise to a more pronounced decay of the rheological and mechanical properties, but, after two extrusion steps, both rheological and mechanical properties seem still useful for the production of film

Leprosy-like cutaneous presentation of Histoplasma capsulatum infection in an African HIV+ patient

Histoplasma capsulatum is an opportunistic dimorphic fungus responsible for most often self-limiting or flu-like infections but potentially lethal in immunocompromised hosts. Histoplasmosis is rare in Europe. We reported a case of disseminated histoplasmosis in an African HIV patient with a leprosy-like primary cutaneous presentation and involvement of lungs, brain, limphnodes and eye. The therapy with liposomial B amphotericin and itraconazole led to a prompt resolution of the symptoms

Investigation on the properties and on the photo-oxidation behaviour of polypropylene/fumed silica nanocomposites

This work investigates the effects of very small amounts of fumed silica on the morphology and on the rheological and mechanical behaviour of polypropylene nanocomposites and on their photo-oxidation behaviour. Polypropylene nanocomposites were prepared using a twin-screw corotating extruder with 0, 1 and 2 wt/wt% of SiO2. Morphological, mechanical, thermomechanical and rheological properties were examined. It was found that the viscosity of the matrix is reduced by the presence of the silica nanoparticles, suggesting a poor adhesion between the two phases and probably some lubricating effect. On the contrary, the mechanical and, in particular, the thermomechanical properties of the matrix are considerably improved by the presence of the silica. In particular, elastic modulus and tensile strength increases remarkably, and this effect becomes more and more remarkable with an increasing temperature. As for the photo-oxidation behaviour, the presence of silica improves the photostability of the polypropylene matrix. This effect has been attributed to both the barrier to the oxygen and to the absorbance of the UV radiation from the silica nanoparticles. Finally, no significant effect of the silica nanoparticles has been put in evidence on the crystallisation behaviour of the polypropylene. As for the effect of the silica content, the difference in the properties of the two nanocomposites is relatively small and all the measured properties depend much less than linearly with its amount. This has been correlated with the reaggregation of the nanoparticles that, having a larger size, decrease the contact area between the matrix and the filler

Toward the Decarbonization of Plastic: Monopolymer Blend of Virgin and Recycled Bio-Based, Biodegradable Polymer

Decarbonization of plastics is based on two main pillars: bio-based polymers and recycling. Mechanical recycling of biodegradable polymers could improve the social, economic and environmental impact of the use of these materials. In this regard, the aim of this study was to investigate whether concentrations of the same recycled biopolymer could significantly affect the rheological and mechanical properties of biodegradable monopolymer blends. Monopolymer blends are blends made of the same polymers, virgin and recycled. A sample of commercially available biodegradable blend was reprocessed in a single-screw extruder until two extrusion cycles were completed. These samples were exposed to grinding and melt reprocessed with 75% and 90% of the same virgin polymer. The blends were characterized by tensile tests and rheological tests. The results obtained showed that while multiple extrusions affected the mechanical and rheological properties of the polymer, the concentration of the reprocessed material present in the blends only very slightly affected the properties of the virgin material. In addition, the experimentally observed trends were accurately predicted by the additive model adopted

Recycling of a multilayer barrier food packaging through the use of a nanofiller: Effect of post-consumer plastic bag conditions

Barrier food packaging films result very difficult to recycle since they are multilayer films composed by at least two different materials. In this context, aim of this study was to assess the use of a nanofiller for the mechanical recycling of multilayer barrier plastic bags used for food vacuum packaging. In particular, graphene nanoplatelets (GnPs) were used as nanofiller studying the effect of their concentration on the properties of the nanocomposites obtained by using polyamide (PA)/polyethylene (PE) bags as polymeric matrix. Moreover, the effect of plastic bags life conditions on the nanocomposite properties were evaluated by exposing the multilayer films to accelerated weathering or to contact with a fatty food simulant (olive oil). The results indicated that the incorporation of GnPs led to an enhancement of the morphology of the polymer blends, consequently resulting in nanocomposites with increased stiffness without a drastic reduction in ductility. The nanocomposites produced using post-consumer bags exhibited lower properties compared to materials produced using pre-consumer bags. However, even in this case, the addition of GnPs contributed to an improvement in the properties demonstrating that the use of this nanofiller can be a viable method to recycle multilayer packaging

PTEN deficiency and mutant p53 confer glucose-addiction to thyroid cancer cells: impact of glucose depletion on cell proliferation, cell survival, autophagy and cell migration.

Proliferating cancer cells oxidize glucose through the glycolytic pathway. Since this metabolism is less profitable in terms of ATP production, cancer cells consume large quantity of glucose, and those that experience insufficient blood supply become glucose-addicted. We have analyzed the response to glucose depletion in WRO and FTC133 follicular thyroid cancer cells, which differ in the expression of two key regulators of the glucose metabolism. WRO cells, which express wild type p53 and PTEN, showed a higher rate of cell proliferation and were much less sensitive to glucose-depletion than FTC133 cells, which are PTEN null and express mutant p53. Glucose depletion slowed-down the autophagy flux in FTC133 cells, not in WRO cells. In a wound-healing assay, WRO cells were shown to migrate faster than FTC133 cells. Glucose depletion slowed down the cell migration rate, and these effects were more evident in FTC133 cells. Genetic silencing of either wild-type PTEN or p53 in WRO cells resulted in increased uptake of glucose, whereas the ectopic expression of PTEN in FTC133 cells resulted in diminished glucose uptake. In conclusion, compared to WRO, FTC133 cells were higher glucose up-taker and consumer. These data do not support the general contention that cancer cells lacking PTEN or expressing the mutant p53R273H are more aggressive and prone to better face glucose depletion. We propose that concurrent PTEN deficiency and mutant p53 leads to a glucose-addiction state that renders the cancer cell more sensitive to glucose restriction. The present observation substantiates the view that glucose-restriction may be an adjuvant strategy to combat these tumours