The role of occupation and a past history of malaria in the etiology of classic Kaposi's sarcoma: a case-control study in north-east Sardinia

A case-control study was performed to determine the role of rural factors including occupation and previous malaria exposure in the development of classic Kaposi's sarcoma (CKS) in a high incidence area of Europe. The occurrence of CKS association with other malignancies was also examined. The results showed that the risk of having CKS was significantly increased in subjects farming cereals, while a previous history of malaria did not influence the risk of developing CKS. A near-significant increase in associated tumours was found.     

Clinical case report: multiple idiosyncratic adverse effects of antiepileptic drugs in trisomy 9p

We report the case of a mentally retarded 30 y.o. patient with partial trisomy of chromosome 9, affected by epilepsy. Following treatment with antiepileptic drugs (AEDs), the patient developed several rare complications: after beginning therapy with phenytoin, the patient developed pseudolymphoma; after monotherapy with carbamazepine (CBZ), the patient thereafter developed myoclonic jerks of upper and lower limbs upon awakening; after one year of treatment with valproate (VPA) the patient developed clinical and immuno-haematological signs of SLE. Gradual withdrawal of AED, obtained clinical remission. The possibility that the chromosomal abnormality of the patient was responsible for the three rare complications observed during AED therapy is considered.     

Sheep Hb I variant, or beta13(A10)Gly-->Ser, in breeds from Corsica: detection by gene sequencing

Nuclear magnetic resonance (NMR) offers the possibility to determine moisture profiles in porous building materials. Moreover, the relaxation of the nuclear magnetic resonance signal can provide additional information on the water distribution in the microstructure. For mortar, it is shown that the transverse relaxation yields information on the distribution of water in the gel pores and capillary pores. Moisture profiles and relaxation were measured during water absorption. The effect of the drying treatment on the microstructure and the water absorption was investigated.     

Diamond wire sawing in ornamental basalt quarries: technical,economic and environmental considerations

The market interest in ornamental rocks commercially referred to as “stones” has grown significantly in recent years, particularly regarding basalt. This has resulted in the widespread use of diamond wire equipped with sintered diamond beads for precision sawing in basalt quarries, especially those located in the industrialized countries; it also has the advantage of preventing rock damages. Diamond wire has been widely used in up-line cutting and other sawing works in both marble and granite quarries for decades; therefore, performance data about the use of this tool on these two different types of rocks are widely documented in academic literature. However, for basalt sawing, information pertaining to the use of diamond wire is unavailable due to various reasons, but mostly because of to its relatively recent introduction in the basalt quarries and also to the historical low market demand for processed basalt in the past. This study offers a possible solution to this lack of information and provides a technical, economic and environmental assessment of diamond wire used in quarrying basalt for ornamental purposes. After an overview on the state of the art of diamond wire and on the final use of processed basalt, the study describes the experimental plan and the results. These show a tool yield much higher than those measured when diamond wire is used on other silicate dimension stones (e.g. granites). Moreover, the composition of basalt sawdust (sludge) has been analysed in the laboratory and has indicated the absence of polluting materials related to tool wear; therefore, basalt sludge, which is made of water and micronized basalt, can be used as a secondary raw material for the environmental restoration of the area or for any other purpose. Further research on other lithotypes is also proposed.

     

A cost-effective cloud computing framework for accelerating multimedia communication simulations

Multimedia communication research and development often requires computationally intensive simulations in order to develop and investigate the performance of new optimization algorithms. Depending on the simulations, they may require even a few days to test an adequate set of conditions due to the complexity of the algorithms. The traditional approach to speed up this type of relatively small simulations, which require several develop–simulate–reconfigure cycles, is indeed to run them in parallel on a few computers and leaving them idle when developing the technique for the next simulation cycle. This work proposes a new cost-effective framework based on cloud computing for accelerating the development process, in which resources are obtained on demand and paid only for their actual usage. Issues are addressed both analytically and practically running actual test cases, i.e., simulations of video communications on a packet lossy network, using a commercial cloud computing service. A software framework has also been developed to simplify the management of the virtual machines in the cloud. Results show that it is economically convenient to use the considered cloud computing service, especially in terms of reduced development time and costs, with respect to a solution using dedicated computers, when the development time is longer than one hour. If more development time is needed between simulations, the economic advantage progressively reduces as the computational complexity of the simulation increases.     

Characterization of direct methanol fuel cell (DMFC) applications with H2SO4 modified chitosan membrane

Chitosan (Chs) flakes were prepared from chitin materials that were extracted from the exoskeleton of Cape rock lobsters in South Africa. The Chs flakes were prepared into membranes and the Chs membranes were modified by cross-linking with H₂SO₄. The cross-linked Chs membranes were characterized for the application in direct methanol fuel cells. The Chs membrane characteristics such as water uptake, thermal stability, proton resistance and methanol permeability were compared to that of high performance conventional Nafion 117 membranes. Under the temperature range studied 20-60 °C, the membrane water uptake for Chs was found to be higher than that of Nafion. Thermal analysis revealed that Chs membranes could withstand temperature as high as 230 °C whereas Nafion 117 membranes were stable to 320 °C under nitrogen. Nafion 117 membranes were found to exhibit high proton resistance of 284 s cm⁻¹ than Chs membranes of 204 s cm⁻¹. The proton fluxes across the membranes were 2.73 mol cm⁻² s⁻¹ for Chs- and 1.12 mol cm⁻² s⁻¹ Nafion membranes. Methanol (MeOH) permeability through Chs membrane was less, 1.4 × 10⁻⁶ cm² s⁻¹ for Chs membranes and 3.9 × 10⁻⁶ cm² s⁻¹ for Nafion 117 membranes at 20 °C. Chs and Nafion membranes were fabricated into membrane electrode assemblies (MAE) and their performances measure in a free-breathing commercial single cell DMFC. The Nafion membranes showed a better performance as the power density determined for Nafion membranes of 0.0075 W cm⁻² was 2.7 times higher than in the case of Chs MEA.