Peroxiredoxin 2 as a chemotherapy responsiveness biomarker candidate in osteosarcoma revealed by proteomics

Purpose : We aimed to identify novel chemotherapy responsiveness biomarkers for osteosarcoma (OS) by investigating the global protein expression profile of 12 biopsy samples from OS patients. Experimental design : Six patients were classified as good responders and six as poor responders, according to the Huvos grading system. The protein expression profiles obtained by 2‐D DIGE consisted of 2250 protein spots. Results : Among them, we identified 55 protein spots whose intensity was significantly different (Bonferroni adjusted p‐value<0.01) between the two patient groups. Mass spectrometric protein identification demonstrated that the 55 spots corresponded to 38 distinct gene products including peroxiredoxin 2 (PRDX 2). Use of a specific antibody against PRDX 2 confirmed the differential expression of PRDX 2 between good and poor responders, while PRDX 2 levels as measured by Western blotting correlated highly with their corresponding 2‐D DIGE values. The predictive value of PRDX 2 expression was further confirmed by examining an additional four OS cases using Western blotting. Conclusions and clinical relevance : These results establish PRDX 2 as a candidate for chemotherapy responsiveness marker in OS. Measuring PRDX 2 in biopsy samples before treatment may contribute to more effective management of OS.     

Water Resources Management and Integrated Water Resources Management (IWRM) in Cameroon

Cameroon is blessed with abundant water resources. Rapid population increase, unplanned urbanisation, intensive industrial and socio-economic development have led to poor and unsustainable management of these resources. Integrated Water Resources Management (IWRM) is a promising approach in ensuring sustainable management of Cameroon’s water resources. It entails management of water for various purposes and not for a single purpose which therefore involves different stake holders aiming at achieving sustainable water resources management. This paper seeks to evaluate recent efforts to implement in IWRM in Cameroon by examining the institutional framework for IWRM in Cameroon, conditions for the implementation of IWRM and proposes reforms for improving IWRM in Cameroon. The paper concludes that reforms such as public participation at local council levels, recognition of water as both an economic and a social good, putting IWRM within the larger context of Integrated Natural Resource Management (INRM) and the exploitation of mathematical models within hydrological basins will improve IWRM in Cameroon.     

Controlling foam morphology of polystyrene via surface chemistry,size and concentration of nanosilica particles

Controlling cell morphologies of polymeric foams is an important part of controlling foam properties. In this study, the effects of particle size, particle content, and particle surface chemistry on cell nucleation in nanosilica/polystyrene (PS) composites are investigated. A theoretical hypothesis on the effect of nanoparticle size on cell nucleation in PS matrix foam was examined. The surface chemistry of nanosilica particles was studied by modifying them with Vinyltriethoxysilane (VTES) silane coupling agent. The microcellular porous materials of neat and composite PS were prepared by batch foaming technique (pressure quench) using supercritical carbon dioxide (ScCO₂) as a blowing agent. It was found that the size of the pores decreases and the cell density increases with the decrease in nanosilica size and the increase of silica loading. It was also observed that the surface treatment of the nanosilica particles have substantial effect on the decrease of the cell size and the increase of the cell density.     

n-octane dehydrocyclisation on monofunctional and bifunctional Pt/Al2O3 catalyst

The dehydrocyclisation of n-octane to iso-octane, ethylbenzene and o-, m- and p-xylene was investigated on monofunctional (non-acidic) and bifunctional (acidic) Pt/Al₂O₃ catalyst in a microcatalytic reactor with hydrogen as carrier at 1.8 atm and 563–673 K. On bifunctional Pt/Al₂O₃, the total conversion of n-octane started from a high value and decreased with increasing temperature for all pulse sizes investigated. The primary product of n-octane conversion on acidic Pt/Al₂O₃ was iso-octane. The product yield-temperature profiles showed a large initial production of iso-octane which decreased to a minimum as the catalyst temperature increased due to its conversion to ethylbenzene and o-xylene. On non-acidic Pt/Al₂O₃, the total conversion of n-octane increased initially and then went through a maximum as the catalyst temperature increased. The primary products of the reaction were found to be ethylbenzene and o-xylene, indicative of the activity of the metal to effect these ring closure reactions.     

Forecasting tunnel geology,construction time and costs using machine learning methods

Neural Computing and Applications - This research intends to use machine learning approaches to predict tunnel geology and its construction time and costs. For this purpose, the Gaussian Process...     

Modified criterion for prediction of tunnel deformation in non-squeezing ground conditions

The strength factor-based criterion for tunnel deformation prediction proposed by Hoek in 2000 is reckoned to be the most practical criterion among the tunnel deformation criteria since 1980s. In view of the fact that Hoek’s criterion was obtained based on case studies under squeezing ground conditions, it has a limited range of applications, applicable mainly in squeezing tunnels. In this work, this criterion was modified by taking into consideration the conditions of eight unstable stations in three non-squeezing tunnels in Iran to amplify its application range. Relative displacements and strength factor (defined as a strength-to-stress ratio) were obtained in unstable stations first. Then, the parametric values were plotted on a Cartesian coordinate’s plane. By using the optimal regression line passing through all points, a criterion for prediction of tunnel deformation was proposed finally. A comparison made between the measured values and the ones predicted by the new criterion shows that the variance accounted for was 77% and the root mean square error was 2%, an acceptable accuracy and a small error implying the effectiveness of the new criterion in tunnel deformation prediction. In addition, the results show that the strength factor of 0.38 can be used to determine the boundary between squeezing and non-squeezing conditions; the behavior and type of failure of the tunnel would be predictable by use of the strength factor.

     

Fabrication of Ge nanoneedles by ion-irradiation method

The Ge surfaces irradiated by Ar⁺ ions at 600 eV with simultaneous Ni supply at room temperature were characterized by various kind of densely distributed nanostructures, such as tiny cones, nanorods with a bottlenecked and nanoneedles, depending on the Ni supply rate during Ar⁺ ion irradiation. As the Ni supply rate decreased, the width of nanostructure formed on the cone tip became thin, and finally slender Ge nanoneedles of 60-80 nm in diameter and 100-300 nm in length were realized. Because the simultaneously supplied Ni fulfills the prerequisite for the so-called “seed” which enhances the surface texturing, size of clustered Ni atoms during of Ar⁺ ion irradiation might affect the size of nanostructures formed after the prolonged sputtering.