Incorporation of 3 μm SiCp into Titanium surfaces using a 2.8 kW laser beam of 186 and 373 MJ m-2 energy densities in a nitrogen environment

The formation of composite layers using a 2.8 kW laser beam of 186 and 373 MJ m−2 energy densities, on commercial purity titanium surfaces preplaced with 3 μm size, 1-4 vol.% SiCp powder in a 100% nitrogen environment, produced gold colour tracks. The tracks gave reflective surfaces after glazing at an energy density of 373 MJ m−2 and dull or a mixture of dull and shiny surfaces at 186 MJ m−2 energy density. Surface cracks were visible in tracks containing 1 and 2 vol.% SiCp, but none were observed in the 4 vol.% SiCp tracks glazed at both energy densities. In the track cross sections, vertical cracks were seen in the 373 MJ m−2 tracks but it was absent in 186 MJm−2 tracks. The SiCp particles completely dissolved in all the tracks processed in this investigation producing a complex and inhomogeneous microstructure of dendrites and needle particles. At the half way of the melt depth from the surface, the dendrites were larger and densely populated, especially after glazing at 373 MJ m−2. The hardness measurement of the MMC layer recorded a wide range of hardness values which gave loops in the hardness profiles. Hardness values ranging from 700 to 1000 Hv were observed up to a melt depth of 1 mm in many tracks and the maximum surface hardness of 2250 Hv was measured in the track containing 1 vol.% SiCp and glazed at 373 MJ m−2. The surface hardness developed 5.6-15 times the base hardness (150 Hv) depending on the dendrite population. The 3 μm size SiCp produced MMC layers 1.5-2 times greater than those previously observed with 6 μm SiCp. The large surface area for an equivalent volume fraction of the three micron carbide particles is considered to have a high laser coupling action and hence absorbed more heat energy to produce deeper melt depth compared to those produced using the 6 μm SiCp

Education and Youth Unemployment in South Africa

The problem of high youth unemployment is a global phenomenon. According to an International Labour Office study in 2004, youth (15-24) make up nearly half (47%) of the world's unemployed, 88 million out of 186 million, even though youth are only 25% of the world's working age population. Of the world's 550 million working poor who cannot lift themselves above US $1 per day poverty measure, 150 million are youth. The ILO estimated in 2004 that halving global youth unemployment would increase global GDP by US$2.2 trillion, 4% of global GDP. These statistics lend weight to the notion that youth unemployment is a problem worthy of attention. In addition, one may argue that addressing unemployment in general would also lower poverty levels and add to GDP (World Bank 2006).

The Future of Testing: Author Index

The Future of Testing: Author Index (12 pages) A Aagard , J. A., 3 1, 32,62 Abrams , R., 229, 230, 232, 236, 243 Adair, F. L., 193,200 Adams, K. M., 223, 236 Adler, P. T. , 197, 200 Airasian, P. W., 33, 5 1,62,94,97, 11 6, 132, 139 Alexander, P. , 55, 67 Alexander, R. A., 32, 62 Alexander, R. S., 50, 65 Algina, 1. , 97 , 11 2, 122 , 124, 137, 142, 143 Allen, D. W., 30, 33,64 Alpert , D., 52, 62 Altemeyer, R. A., 46, 62 Amos, K. M. , 130, 133 Anastas i, A., 10 , 18, 25,78 , 79,80,87, 189, 199 ,200, 272,287 Anastasio , E. 1., 3 1, 64 Anderson, B., 75, 87 Anderson, D., 2 13, 2 14, 229, 230 , 243 Anderson, R. c., 104, 133 Andreasen, N. c., 23 1, 236 Andresky, S., 13, 25 Andrew, B. 1. , III , 133, 150, 155, 179 Angoff, W. H. , 109, III , 11 8, 125, 128 , 138, 150, 179 Anthony , W. Z., 209, 220, 236 Archambault , F. X., 111 , 133 ... Y/Z Yagel, 1. c. , 54, 64 Yallow, E. S., 11 7, 143 Yen, W. M., 34, 69 Yeudall , L. T. , 232, 238 York, R. L., 17, 25 Young, L. D. , 23 1, 244 Ysseldyke, J. E., 11 9, 143 Zachary , R. A., 29 , 42,57,59,69 Zatz, L. M. , 232 , 239 Zelazowski, R., 232, 239 Zener, T. B. , 254, 267 Zieky , M. 1. , 107, 109, 11 2, 11 3, 114, 128, 138 Zigmond, N., 11 6, 138 Zisk in , 1. , 186 , 188 , 189 , 190 , 191, 201 Zuger, R. , 234, 244 Zytowski , D. G. , 246, 248, 252 , 254, 255 , 26

The Future of Testing: Author Index

The Future of Testing: Author Index (12 pages) A Aagard , J. A., 3 1, 32,62 Abrams , R., 229, 230, 232, 236, 243 Adair, F. L., 193,200 Adams, K. M., 223, 236 Adler, P. T. , 197, 200 Airasian, P. W., 33, 5 1,62,94,97, 11 6, 132, 139 Alexander, P. , 55, 67 Alexander, R. A., 32, 62 Alexander, R. S., 50, 65 Algina, 1. , 97 , 11 2, 122 , 124, 137, 142, 143 Allen, D. W., 30, 33,64 Alpert , D., 52, 62 Altemeyer, R. A., 46, 62 Amos, K. M. , 130, 133 Anastas i, A., 10 , 18, 25,78 , 79,80,87, 189, 199 ,200, 272,287 Anastasio , E. 1., 3 1, 64 Anderson, B., 75, 87 Anderson, D., 2 13, 2 14, 229, 230 , 243 Anderson, R. c., 104, 133 Andreasen, N. c., 23 1, 236 Andresky, S., 13, 25 Andrew, B. 1. , III , 133, 150, 155, 179 Angoff, W. H. , 109, III , 11 8, 125, 128 , 138, 150, 179 Anthony , W. Z., 209, 220, 236 Archambault , F. X., 111 , 133 ... Y/Z Yagel, 1. c. , 54, 64 Yallow, E. S., 11 7, 143 Yen, W. M., 34, 69 Yeudall , L. T. , 232, 238 York, R. L., 17, 25 Young, L. D. , 23 1, 244 Ysseldyke, J. E., 11 9, 143 Zachary , R. A., 29 , 42,57,59,69 Zatz, L. M. , 232 , 239 Zelazowski, R., 232, 239 Zener, T. B. , 254, 267 Zieky , M. 1. , 107, 109, 11 2, 11 3, 114, 128, 138 Zigmond, N., 11 6, 138 Zisk in , 1. , 186 , 188 , 189 , 190 , 191, 201 Zuger, R. , 234, 244 Zytowski , D. G. , 246, 248, 252 , 254, 255 , 26

Urease Inhibitor Application Stages and Nitrogen Levels Influenced on Morpo-Phenological Traits of Wheat Cultivars

A field trial was carried out at New Developmental Farm of The University Agriculture, Peshawar, Pakistan during winter 2012-13, in order to study the urease inhibitor application stages and nitrogen levels influenced on morpo-phenological traits of wheat cultivars. Therefore the field experiment was conducted in randomized complete block design with split plot arrangement having four replications.  Nitrogen levels (60, 120 and 150 kg ha-1) and urease inhibitor  stages (100% sowing stage, 50% sowing stage + 50% booting stage and 100% booting stage) were allotted to main plots, while  wheat cultivars (Siran and Atta Habib)  were allotted to sub plots.  Plots treated with 120 kg N ha-1 took maximum days to booting (128), improved plant height (97.9 cm), leaf area tiller-1 (117.8 cm2), spike length (11.3 cm) and biological yield (10382 kg ha-1) but maximum (185) days to maturity  was observed when plots treated with 150 kg N ha-1 as compared with control plots. Application of urease inhibitor 100% at sowing stage took maximum booting (133) days, maturity (186) days, improved plant height (102 cm), leaf area tiller-1 (128 cm2), spike length (11.6 cm) and biological yield (11386 kg ha-1) as compared with urease application 100% at booting stage. Wheat cultivar Siran had significantly took maximum booting (123) days, maturity (178) days, plant height (94.5 cm), leaf area tiller-1 (97.6 cm2), spike length (10.3 cm) and biological yield (9331 kg ha-1) as compared to Atta Habib. Hence cultivar Siran treated with 120 kg N ha-1 and coated urease inhibitor 100% at sowing stage produced the best results in terms of plant height, leaf area tiller-1, physiological maturity and biological yield. Keywords: Wheat (Triticum aestivum L.), urease inhibitor application stages, nitrogen levels, wheat cultivars, phenology, morpholog

The role of the long non coding RNA HAS2-AS1 in breast cancer cells

Extracellular matrix (ECM) is a network made by proteins and proteoglycans, whose structure is essential to maintain tissue architecture and to provide molecules diffusion and cellular communications. A deregulated synthesis of ECM components is often associated to a pathological status. Among various glycosaminoglycans, hyaluronan (HA) is a ubiquitous ECM component with a remarkable structural importance. It is able to modulate cell adhesion, motility, growth and inflammation after the binding with cellular receptors (CD44 and RHAMM) and the activation of different cellular pathways. In tumour microenvironment, the up-regulation of HAS2 and the overproduction of HA are often associated with tumour progression and metastasis. This also applies to breast cancer, where the accumulation of HA and the overexpression of hyaluronan synthases (HASes) in stromal and tumoral cells correlate with tumor malignancy and patients survival. The study of the regulation of HAS2, the main enzyme in the production of HA, is very important to understand the development and the progression of breast cancer. Recently, it has been discovered that the lncRNA HAS2-AS1 can modulate the expression of HAS2 and the production of hyaluronan in aortic smooth muscle cells via epigenetic modifications [1]. Although the role of HA and HAS2 in breast cancer is widely described, little is known about HAS2-AS1. Given this considerations, the aim of this project is to study the role of HAS2-AS1 in breast cancer. In particular, we compared the behaviour of MDA-MB-231 and MCF-7 cells after the modulation of HAS2-AS1 expression with functional assays evaluating cell proliferation, migration and invasion. In the same conditions, we analysed the expression of HA related genes and receptors in MDA-MB-231 cells. This analysis revealed that HAS2-AS1 knockdown stimulated the presence of a malignant phenotype, as its abrogation increased cell motility and invasion, as well as the expression of several HA related genes and the receptor CD44. These evidences suggested that HAS2-AS1 plays an important role breast tumor progression through alteration of HA metabolism. Further analysis were conducted to understand the molecular mechanisms at the basis of the changes observed. LncRNAs can orchestrate gene expression through a variety of mechanisms, regulating transcription and translation, chromatin remodelling and the interaction with other RNA species, i.e. miRNAs. HAS2-AS1 transcript contains a putative binding site for miRNA 186, a negative regulator of the pro-apoptotic receptor P2X7 [2]. In our results we demonstrated that the overexpression of HAS2-AS1 decreased the abundance of miR-186, while the transcript of P2X7 and other targets of miRNA 186 (involved in cell cycle and autophagy) raised. All together, these data suggest that the \u201csponge effect\u201d of HAS2-AS1 is able to antagonise the function of miRNA 186 on its downstream targets and could explain the presence of a malignant phenotype after HAS2-AS1 silencing in MDA-MB-231. 1. Vigetti D, Deleonibus S, Moretto P, Bowen T, Fischer JW, Grandoch M, et al. Natural antisense transcript for hyaluronan synthase 2 (HAS2-AS1) induces transcription of HAS2 via protein O-GlcNAcylation. J. Biol. Chem. 2014;289:28816\u201326. 2. Zhou L, Qi X, Potashkin JA, Abdul-Karim FW, Gorodeski GI. MicroRNAs miR-186 and miR-150 down-regulate expression of the pro-apoptotic purinergic P2X7 receptor by activation of instability sites at the 3\u2b9-untranslated region of the gene that decrease steady-state levels of the transcript. J. Biol. Chem. 2008;283:28274\u201386

PENYISIHAN PEWARNA TEKSTIL REAKTIF OLEH JAMUR PELAPUK PUTIH DAN EKSTRAK KASAR ENZIM LAKASE YANG DIPRODUKSI PADA SUBMERGED FERMENTATION FORM

Abstrak: Pengolahan air limbah tekstil yang mengandung antrakuinon dan pewarna azo merupakan tantangan besar karena struktur aromatik dan toksisitasnya yang kompleks. Penelitian ini mempelajari penyisihan pewarna antrakuinon reactive blue 4 (RB4), single azo reactive orange 16 (RO16), dan diazo reactive red 120 (RR120) juga reactive black 5 (RB5) dengan konsentrasi awal 150 mg/L dalam medium padat (PDA) dan submerged fermentation form (SFF) menggunakan berbagai jamur pelapuk putih (JPP). T. versicolor memiliki aktivitas enzim dominan terbaik (lakase) di antara JPP lain (186 U.l-1). Studi penyisihan warna diamati pada kondisi SFF dan hanya menggunakan ekstrak kasar enzim lakase. Untuk kultur cairan jamur menggunakan medium kirk, T. versicolor secara positif dapat menyisihkan pewarna tekstil reaktif. Diantara empat pewarna yang digunakan, RB4 memiliki persentase penyisihan warna tertinggi (99,99%), dibandingkan dengan RB5 (98,03%), RR120 (90,56%) dan RO16 (63,52%). Uji stabilitas pH dan suhu menunjukkan bahwa ekstrak kasar enzim lakase memiliki aktivitas terbaik dalam kisaran pH 2,4 dan suhu 20 0C. Persentase penyisihan warna terbaik menggunakan ekstrak kasar enzim lakase adalah RB4 yaitu 99,84% dengan waktu inkubasi selama 60 menit. Metabolit yang terbentuk setelah biotransformasi oleh ekstrak kasar enzim lakase diamati menggunakan FTIR. Hasil spektra FTIR menunjukkan bahwa struktur antrakuinon, ikatan nitrogen, dan gugus amina RB4 dapat dipecah oleh ekstrak kasar enzim lakase. Studi toksisitas menggunakan Bacillus sp. menegaskan bahwa produk biotransformasi RB4 berkurang toksisitasnya dibandingkan dengan pewarna induk sebelum dilakukan pengolahan. Kata kunci: Azo, Antrakuinon, Jamur pelapuk putih, Lakase Abstract: Treatment of textile wastewater containing anthraquinone and azo dye is quite a huge challenge due to its complex aromatic structure and toxicity. This study investigated the decolorization of anthraquinone dye reactive blue 4 (RB4), Single azo reactive orange 16 (RO16), and diazo reactive red 120 (RR120) also reactive black 5 (RB5) with initial concentration of 150 mg/l in solid medium (PDA) and Submerged fermentation form (SFF) by various white rot fungi (WRF). T. versicolor has the best dominant enzyme activity (laccase) among others WRF (186 U.l-1). Decolorization study was observed in both SFF condition and using only crude enzyme. For SFF using kirk medium T. versicolor positively degrading reactive textile dyes. Among four different dyes, RB4 has the highest decolorization percentage (99.99%), compared to RB5 (98.03 %), RR120 (90.56 %) and RO16 (63.52 %). pH and thermo stability test show that laccase crude enzyme has the best activity in pH range 2.4 and temperature of 20 0C. The best decolouration percentage using crude enzyme is RB4 as obtained 99.84% in 60 min. The metabolites formed after biotransformation was characterized by FT-IR. The results of FTIR spectra showed that the anthraquinone structures, nitrogen linkages and amino groups of RB4 were destroyed by laccase crude enzyme. Toxicity study using Bacillus sp. confirmed that biotransformation product of RB4 is less toxic compared to parent dye.   Keywords: Azo, Anthraquinone, Laccase, White rot fung

An investigation into the thermolysts reactions of polyfluoroaromatic prop-2-ynyl ethers and thioethers

This work investigates the thermal behaviour of polyfluoroaryl prop-2-ynyl ethers and thioethers in the vapour phase and solution phase. It also reports the thermolyses of 2-fluoromethyl-4,5,6,7,8,9-hexafluoronaphtho (2,1-b) furan (l6l) in the presence of 2,3-dimethylbut-2-ene and 3,3-dimethylbut-l-ene respectively. Chapter 1 discusses the history, mechanism and stereochemistry of the Glaisen and thio-Claisen rearrangements of aromatic prop-2-enyl and prop-2-ynyl systems. While Chapter 2, reports on the various cyclisation reactions that may follow an initial Glaisen rearrangement. Chapter 3 deals with the literature on the Glaisen and thio-Claisen rearrangements of polyfluoroaryl systems which are directly related to those under study in this thesis. Chapters 4 and 5 describe the isomerisation reactions of pentafluorophenyl prop-2-ynyl thioether (167) and 1,3,4,5,6,7,8-heptafluoro-2-naphthyl prop-2-ynyl thioether (171). Chapter 4 is concerned with the reaction of compound (167) with p-xylene and benzene at 180 C and in the presence of BF (_3)-etherate, at 25 C. Chapter 5 reports upon the reactions of the thioether (171) with benzene and p-xylene at l40 C and 160 C. At l60 G, in nickel apparatus the isomerisation product 2-fluoromethyl-4,5,6,7,8,9-hexafluoronaphtho (2,1-b) thiophen (173) is shown to be an intermediate in the conversion of the thioether (171) to the substitution product, 2-(2,5-dimethylbenzyl)-4,5,6,7,8,9-hexafluoronaphtho (2,1-b) thiophen (173) with p-xylene. This chapter also highlights the differing courses of reactions of the thioether (17l) in glass and nickel apparatus. Chapter 6 reports the isomerisation reactions of 1, 3, 4, 5, 6, 7, 8-heptafluoro-2-naphthyl prop-2-ynyl-ynyl ether (156) in both the liquid phase and vapour phase. The glass surface of the reaction vessel was shown to act as a Lewis-acid catalyst at elevated temperatures, in the reaction of the naphthyl ether (156) with p-xylene and isopropylbenzene to give the aromatic substitution products (159) and (160) respectively. Whereas in nickel apparatus, the 2-fluoromethyl compound (161) was the main product in both reactions. Chapter 7 discusses the mechanism of the isomerisation reactions of the polyfluoroaryl prop-2-ynyl ethers and thioethers studied in this thesis. It also incorporates a critical experiment in which compound (161) is reacted with N, N-diethylaniline at 140 C only to be recovered unchanged. (The thermolysis of (161) in p-xylene at the, same temperature gives the substitution product (159) exclusively) The charge-separated species (197) and (195) are proposed as intermediates in the reactions of the ether (156) and thioether (171) via the heterolytic fission of the sp (^3) C-F bond in the Claisen rearrangement intermediates (157) and (172) respectively. It is concluded that the isomerisation reactions of (I56) and (171), which require a 1, 4-fluorine shift, proceed via an ionic mechanism. The final chapter describes the thermolysis reactions of the naphthyl ether (156) and the 2-fluoromethyl compound (161) with 2, 3-dimethylbut-2-ene and 3, 3-dimethylbut-l-ene. Compounds (156) and (161) react with 2, 3-dimethylbut-2-ene at 150 C to give 2-(2,2,3-trimethylbut-3-enyl)-4,5,6,7,8,9-hexafluoronaphtho (2,1-b) furan (186) and a small amount of 2-(2,3,3-trlmethylbut-l.enyl)-4,5,6,7,8,9-hexafluoro-naphtho(2,1-b) furan (187) compound (161) reacts with 3,3-dimethylbut-l-ene at 25 C in the presence of BF(_3) -etherate to give the Markovnikov addition-elimination product, 2-(3,4-dimethylpent-3-enyl)-4,5,6,7,8,9-hexafluoro-naphtho (2,1-b) furan (194) and a small amount of (186). Thermolysis of both (156) and (161) with 3, 3-dimethylbut-1ene gave (186) as the major product accompanied by smaller amounts of (187) and (194). It is proposed that compounds (186) and (187) arise via reaction with 2, 3-dimethylbut-2-ene formed by isomerisation of the terminal alkene. 2-Chloromethyl -4, 5, 6, 7, 8, 9-hexafluoronaphtho (2,l-b) furan (161a) has been prepared; it reacts with 3,3-dimethylbut-l-ene in the presence of ZnCl (_2), to give (186), (194) and (196)

The role of the long non coding RNA HAS2-AS1 in breast cancer cells

Extracellular matrix (ECM) is a network made by proteins and proteoglycans, whose structure is essential to maintain tissue architecture and to provide molecules diffusion and cellular communications. A deregulated synthesis of ECM components is often associated to a pathological status. Among various glycosaminoglycans, hyaluronan (HA) is a ubiquitous ECM component with a remarkable structural importance. It is able to modulate cell adhesion, motility, growth and inflammation after the binding with cellular receptors (CD44 and RHAMM) and the activation of different cellular pathways. In tumour microenvironment, the up-regulation of HAS2 and the overproduction of HA are often associated with tumour progression and metastasis. This also applies to breast cancer, where the accumulation of HA and the overexpression of hyaluronan synthases (HASes) in stromal and tumoral cells correlate with tumor malignancy and patients survival. The study of the regulation of HAS2, the main enzyme in the production of HA, is very important to understand the development and the progression of breast cancer. Recently, it has been discovered that the lncRNA HAS2-AS1 can modulate the expression of HAS2 and the production of hyaluronan in aortic smooth muscle cells via epigenetic modifications [1]. Although the role of HA and HAS2 in breast cancer is widely described, little is known about HAS2-AS1. Given this considerations, the aim of this project is to study the role of HAS2-AS1 in breast cancer. In particular, we compared the behaviour of MDA-MB-231 and MCF-7 cells after the modulation of HAS2-AS1 expression with functional assays evaluating cell proliferation, migration and invasion. In the same conditions, we analysed the expression of HA related genes and receptors in MDA-MB-231 cells. This analysis revealed that HAS2-AS1 knockdown stimulated the presence of a malignant phenotype, as its abrogation increased cell motility and invasion, as well as the expression of several HA related genes and the receptor CD44. These evidences suggested that HAS2-AS1 plays an important role breast tumor progression through alteration of HA metabolism. Further analysis were conducted to understand the molecular mechanisms at the basis of the changes observed. LncRNAs can orchestrate gene expression through a variety of mechanisms, regulating transcription and translation, chromatin remodelling and the interaction with other RNA species, i.e. miRNAs. HAS2-AS1 transcript contains a putative binding site for miRNA 186, a negative regulator of the pro-apoptotic receptor P2X7 [2]. In our results we demonstrated that the overexpression of HAS2-AS1 decreased the abundance of miR-186, while the transcript of P2X7 and other targets of miRNA 186 (involved in cell cycle and autophagy) raised. All together, these data suggest that the “sponge effect” of HAS2-AS1 is able to antagonise the function of miRNA 186 on its downstream targets and could explain the presence of a malignant phenotype after HAS2-AS1 silencing in MDA-MB-231. 1. Vigetti D, Deleonibus S, Moretto P, Bowen T, Fischer JW, Grandoch M, et al. Natural antisense transcript for hyaluronan synthase 2 (HAS2-AS1) induces transcription of HAS2 via protein O-GlcNAcylation. J. Biol. Chem. 2014;289:28816–26. 2. Zhou L, Qi X, Potashkin JA, Abdul-Karim FW, Gorodeski GI. MicroRNAs miR-186 and miR-150 down-regulate expression of the pro-apoptotic purinergic P2X7 receptor by activation of instability sites at the 3ʹ-untranslated region of the gene that decrease steady-state levels of the transcript. J. Biol. Chem. 2008;283:28274–86