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A developed methodology for determining the physical properties of mineral fibers prepared from different input mixtures under the same spinning wheel conditions is described and discussed. Energy dispersive X-ray fluorescence spectroscopy was combined with simultaneous thermal analysis and thermogravimetry to study the mineralogical composition and typical melting and crystallization temperatures. The mechanical properties measured with nanoindentation were related to the mineralogical properties and the results obtained are in agreement with the literature. The developed methodology shows reliable performance and demonstrates the ability to study the mechanical properties of mineral fibers, their mineralogical composition, and thermal properties. The presented experimental methodology opens up the possibility of researching the mechanical properties of mineral fibers for the purpose of defining production recipes in the field of mineral thermal insulation materials.

Bacterial infections are an increasingly serious issue worldwide. The inability of existing therapies to treat multidrug-resistant pathogens has been recognized as an important challenge of the 21st century. Efflux pumps are important in both intrinsic and acquired bacterial resistance and identification of small molecule efflux pump inhibitors (EPIs), capable of restoring the effectiveness of available antibiotics, is an active research field. In the last two decades, much effort has been made to identify novel EPIs. However, none of them has so far been approved for therapeutic use. In this article, we explore different structural families of currently known EPIs for multidrug resistance efflux systems in the most extensively studied pathogens (NorA in Staphylococcus aureus, AcrAB-TolC in Escherichia coli, and MexAB-OprM in Pseudomonas aeruginosa). Both synthetic and natural compounds are described, with structure-activity relationship studies and optimization processes presented systematically for each family individually. In vitro activities against selected test strains are presented in a unifying manner for all the EPIs described, together with the most important toxicity, pharmacokinetic and in vivo efficacy data. A critical evaluation of lead-likeness characteristics and the potential for clinical development of the most promising inhibitors of the three efflux systems is described. This overview of EPIs is a good starting point for the identification of novel effective antibacterial drugs.

Štore Steel produces steel grades for spring, forging and engineering industry applications. Steelmaking technology consists of scrap melting in Electric Arc Furnace (EAF), secondary metallurgy in Ladle Furnace (LF) and continuous casting of billets (CC). Hydrogen content during steelmaking of various steel grades and steelmaking technologies was measured. Samples of steel melt from EAF, LF and CC were collected and investigated. Sampling from Electric Arc Furnace and Ladle Furnace was carried out using vacuum pin tubes. Regular measurements of hydrogen content in steel melt were made using Hydris device. Hydrogen content results measured in tundish by Hydris device were compared with results from pin tube samples. Based on the measurement results it was established that hydrogen content during steelmaking increases. The highest values were determined in tundish during casting. Factors that influence the hydrogen content in liquid steel the most were steelmaking technology and alloying elements.

The objective of the research that has been presented was to model the effect of differences in chemical composition within one steel grade on hardenability, with a very broad and heterogeneous database used for studying hardness predictions. This article presents the second part of research conducted with neural networks. In the previous article [1] the most influential parameters were defined along with their weights and on the basis of these results, an improved model for predicting hardenability was developed. These developed neural networks were applied to model predictions of hardenability for three steel grades VCNMO150, CT270 and 42CrMoS4. The results proved that the correlation between the chemical composition differences within a chosen steel grade and the hardness changes can be modeled. If the database is big enough, predictions would be accurate and of high quality. But for a less comprehensive database, the differences in hardness predictions for various chemical compositions of the steel grade concernedwere observable.

A die was investigated for the pressure die-casting of Mg-alloy. The die was made of martensitic chromium hot-work steel grade and the surface was gas nitrided. Due to damaged surface the die was removed from the production line after 20.000 shots. Light microscopy and electron microscopy studies were performed. Mechanical properties as well as fracture toughness of the basic material were determined. The results of the investigations are presented. It was established that the base material properties correspond to declared properties. The corrosion phenomena in the form of pits were observed on all surfaces of the die. Metallography revealed that the nitrided layer consisted only of diffusion layer, without a γ′ compound layer. The depth of the pits was limited to the thickness of nitrided layer and in the pits the presence of Ca, Cl and S was detected. No cracks were observed in nitrided layer and all the edges of pits were rounded. The damages were caused by a combined mechanism of corrosion–erosion. The main reasons for the damages were not optimised nitride layer properties.

A mathematical model of continuous casting of steel slabs and billets that takes into account aspects relating to computer capacities was developed. The starting point for the model was the solution of a partial differential equation of heat conduction for different boundary conditions using the finite-difference method. A numerical solution technique was implemented via the Pascal and C computer programs running under the GNU/Linux operating system, and their speeds of computation were compared. The model is capable of predicting temperature profiles and the solidification front in continuously cast steel strand to make slabs and billets. The accuracy of the model was tested by obtaining approximate solutions with two different sets of mesh points, one with half the spacing of the other, and the temperatures at four representative spatial positions were compared. The ability of the mathematical model built to predict the temperature distribution and the shell thickness reliably was tested using a solidif...

Hot tests of foaming behaviour of steelmaking slags were conducted on a laboratory scale up to 1760 °C using a Tammann furnace. The foaming behaviour of the slags was quantified on the basis of a new measuring method. The volume increase and the progress of the foaming process can be continuously observed and calculated by means of picture analysis. The gas content of foaming slags was compared with the results of the measurements performed in steel plants. The influence of the magnesia content on the foaming behaviour is investigated. The chemical composition of the slag is beside the CO evolution the decisive factor influencing slag foaming behaviour. The highest volume increase values observed lie in the region of 2500 % in relation to the initial volume.

The report presents data on HIV infection among men who have sex with men (MSM) in Slovenia during 1999-2008. HIV surveillance was based on universal mandatory reporting of HIV/AIDS cases, monitoring HIV infection prevalence among sentinel populations of MSM and STI patients and selected behaviour indicators in a sentinel population of MSM. Among 48 newly diagnosed HIV cases reported for 2008, 34 were MSM. Since 1999, the annual reported rate of HIV diagnoses in MSM rose from 7.1 to 46.8 per million men aged 15-64 years (an increase of more than six times). During 1999-2008, the proportion of MSM diagnosed with AIDS within three months of HIV diagnosis declined from 60% to 21%, however, the corresponding rate per million men aged 15-64 increased from 4.3 to 9.6. During 1999-2008, HIV prevalence among male clients of STI outpatient services tested for syphilis (including a substantial proportion of MSM) increased from 0% to 3.4%, and it remained below 5% in a sentinel population of MSM in Ljubljana. In the same sentinel population of MSM, the proportion reporting HIV test last year increased from 29% in 2003 to 38% in 2008 while the proportion reporting condom use at last anal intercourse decreased from 81% in 2004 to 66% in 2008. The burden of HIV among MSM in Slovenia is disproportionately high and increasing fast. Promotion of safer sexual behaviour and HIV testing among MSM as well as positive prevention among MSM with diagnosed HIV infection are urgently needed.

We treated 60 patients with cisplatin-based combination chemotherapy before definitive surgery and/or radiation. All had squamous cell tumors of the head and neck, stages II to IV, M0. Twelve patients (20%) achieved a complete remission after chemotherapy. Eight of these patients showed no histologic evidence of residual disease after biopsy or surgery. Definitive local therapy with surgery and/or radiation was carried out on almost all patients regardless of the extent of the response to preceding chemotherapy. Chemotherapy-induced complete responders have had an improved survival rate in comparison with patients achieving a partial response or less. The extent of primary tumor correlates inversely with a complete response to chemotherapy.