Survey and Clearance of Unexploded Submunitions Versus Landmines and Other ERW

The authors argue that survey and clearance methods in areas contaminated solely by unexploded submunitions (from cluster munitions) should be different than those in areas contaminated by mines and other explosive remnants of war to achieve the most efficient outcome. This article seeks to explain how and why procedures are different, and proposes a land-release methodology for dealing with unexploded submunitions

A Model of Proto-Anti-Codon RNA Enzymes Requiring l-Amino Acid Homochirality

All living organisms encode the 20 natural amino acid units of polypeptides using a universal scheme of triplet nucleotide “codons”. Disparate features of this codon scheme are potentially informative of early molecular evolution: (i) the absence of any codons for d-amino acids; (ii) the odd combination of alternate codon patterns for some amino acids; (iii) the confinement of synonymous positions to a codon’s third nucleotide; (iv) the use of 20 specific amino acids rather than a number closer to the full coding potential of 64; and (v) the evolutionary relationship of patterns in stop codons to amino acid codons. Here I propose a model for an ancestral proto-anti-codon RNA (pacRNA) auto-aminoacylation system and show that pacRNAs would naturally manifest features of the codon table. I show that pacRNAs could implement all the steps for auto-aminoacylation: amino acid coordination, intermediate activation of the amino acid by the 5′-end of the pacRNA, and 3′-aminoacylation of the pacRNA. The anti-codon cradles of pacRNAs would have been able to recognize and coordinate only a small number of l-amino acids via hydrogen bonding. A need for proper spatial coordination would have limited the number of chargeable amino acids for all anti-codon sequences, in addition to making some anti-codon sequences unsuitable. Thus, the pacRNA model implies that the idiosyncrasies of the anti-codon table and l-amino acid homochirality co-evolved during a single evolutionary period. These results further imply that early life consisted of an aminoacylated RNA world with a richer enzymatic potential than ribonucleotides alone

Aerobic oxidation of thiols to disulfides by heterogeneous gold catalysts

Thiols are smoothly and efficiently oxidized to disulfides (RSSR) with air in the presence of gold nanoparticles supported on CeO2 in absence of solvent, as well as in aqueous solutions and neutral pH. It is shown that the reaction can occur through the coupling of two sulphur radicals on the metal surface. The sulphur radicals are formed from thiols by one-electron oxidation with the metal. This reaction mechanism strongly resembles that found for sulfhydryl oxidases, a class of enzymes which are involved in the oxidative protein folding through de novo formation of disulfides from thiols.lFinancial support by Consolider-Ingenio 2010 (project MULTICAT), Spanish MICINN (Projects MAT2006-14274-C02-01 and MAT2011-28009), Generalitat Valenciana (Project PROMETEO/2008/130) and Fundacion Areces are gratefully acknowledged. T.R. expresses her gratitude to Consejo Superior de Investigaciones Cientificas for an I3-P fellowship.Corma Canós, A.; Ródenas Torralba, T.; Sabater Picot, MJ. (2012). 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Tetrahedron, 42(2), 719-725. doi:10.1016/s0040-4020(01)87476-7McKillop, A., Koyunçu, D., Krief, A., Dumont, W., Renier, P., & Trabelsi, M. (1990). Efficicient, high yield, oxidation of thiols and selenols to disulphides and diselenides. Tetrahedron Letters, 31(35), 5007-5010. doi:10.1016/s0040-4039(00)97790-6Ramesha, A. R., & Chandrasekaran, S. (1994). A facile entry to macrocyclic disulfides: an efficient synthesis of redox-switched crown ethers. The Journal of Organic Chemistry, 59(6), 1354-1357. doi:10.1021/jo00085a025Ramadas, K., & Srinivasan, N. (1995). Sodium Chlorite - Yet Another Oxidant for Thiols to Disulphides. Synthetic Communications, 25(2), 227-234. doi:10.1080/00397919508010811Pryor, W. A., Church, D. F., Govindan, C. K., & Crank, G. (1982). Oxidation of thiols by nitric oxide and nitrogen dioxide: synthetic utility and toxicological implications. The Journal of Organic Chemistry, 47(1), 156-159. doi:10.1021/jo00340a038Iranpoor, N., Firouzabadi, H., & Zolfigol, M. A. (1998). Dinitrogen Tetroxide Copper Nitrate Complex [Cu(NO3)2.N2O4] As a New Nitrosating Agent for Catalytic Coupling of Thiols via Thionitrite. Synthetic Communications, 28(2), 367-375. doi:10.1080/00397919808005729Wu, X., Rieke, R. D., & Zhu, L. (1996). Preparation of Disulfides by the Oxidation of Thiols Using Bromine. Synthetic Communications, 26(1), 191-196. doi:10.1080/00397919608003879Ali, M. H., & McDermott, M. (2002). Oxidation of thiols to disulfides with molecular bromine on hydrated silica gel support. Tetrahedron Letters, 43(35), 6271-6273. doi:10.1016/s0040-4039(02)01220-0Khazaei, A., Zolfigol, M. A., & Rostami, A. (2004). 1,3-Dibromo-5,5-Dimethylhydantoin [DBDMH] as an Efficient and Selective Agent for the Oxidation of Thiols to Disulfides in Solution or under Solvent-Free Conditions. Synthesis, (18), 2959-2961. doi:10.1055/s-2004-834919Joshi, A. V., Bhusare, S., Baidossi, M., Qafisheh, N., & Sasson, Y. (2005). Oxidative coupling of thiols to disulfides using a solid anhydrous potassium phosphate catalyst. Tetrahedron Letters, 46(20), 3583-3585. doi:10.1016/j.tetlet.2005.03.040Patel, S., & Mishra, B. K. (2004). Cetyltrimethylammonium dichromate: a mild oxidant for coupling amines and thiols. Tetrahedron Letters, 45(7), 1371-1372. doi:10.1016/j.tetlet.2003.12.068Leino, R., & Lönnqvist, J.-E. (2004). A very simple method for the preparation of symmetrical disulfides. Tetrahedron Letters, 45(46), 8489-8491. doi:10.1016/j.tetlet.2004.09.100Delaude, L., & Laszlo, P. (1996). A Novel Oxidizing Reagent Based on Potassium Ferrate(VI)1. The Journal of Organic Chemistry, 61(18), 6360-6370. doi:10.1021/jo960633pPeskin, A. V., & Winterbourn, C. C. (2001). Kinetics of the reactions of hypochlorous acid and amino acid chloramines with thiols, methionine, and ascorbate. Free Radical Biology and Medicine, 30(5), 572-579. doi:10.1016/s0891-5849(00)00506-2Akdag, A., Webb, T., & Worley, S. D. (2006). Oxidation of thiols to disulfides with monochloro poly(styrenehydantoin) beads. Tetrahedron Letters, 47(21), 3509-3510. doi:10.1016/j.tetlet.2006.03.105Kirihara, M., Asai, Y., Ogawa, S., Noguchi, T., Hatano, A., & Hirai, Y. (2007). A Mild and Environmentally Benign Oxidation of Thiols to Disulfides. Synthesis, 2007(21), 3286-3289. doi:10.1055/s-2007-990800LIU, K.-T., & TONG, Y.-C. (1978). A Facile Conversion of Thiols to Disulfides. Synthesis, 1978(09), 669-670. doi:10.1055/s-1978-24844Rao, T. V., Sain, B., Murthy, P. S., Rao, T. S. R. P., Joshi, G. C., & Jain, A. K. (1997). Iron(III )–Ethylenediaminetetraacetic AcidMediated Oxidation of Thiols to Disulfides with MolecularOxygen†. Journal of Chemical Research, (8), 300-301. doi:10.1039/a702061iWalters, M. A., Chaparro, J., Siddiqui, T., Williams, F., Ulku, C., & Rheingold, A. L. (2006). The formation of disulfides by the [Fe(nta)Cl2]2− catalyzed air oxidation of thiols and dithiols. Inorganica Chimica Acta, 359(12), 3996-4000. doi:10.1016/j.ica.2006.03.043Rao, T. V., Rao, K. N., Jain, S. L., & Sain, B. (2002). COBALT PHTHALOCYANINE MEDIATED AEROBIC OXIDATION OF THIOLS: A SIMPLE AND CONVENIENT PREPARATION OF DISULPHIDES. Synthetic Communications, 32(8), 1151-1157. doi:10.1081/scc-120003604Simándi, L. I., Németh, S., & Rumelis, N. (1987). Cobalt(II) ion catalyzed oxidation of o-substituted anilines with molecular oxygen. Journal of Molecular Catalysis, 42(3), 357-360. doi:10.1016/0304-5102(87)85011-3S. Uemura , Comprehensive Organic Synthesis, B. M. Trost, I. Fleming Ed., Pergamon Press, New York, 1991, Vol 7., 757Hashemi, M. M., & Karimi-Jaberi, Z. (2004). Oxidation of Thiols to Disulfides by Oxygen in Presence of Cobalt(II) and Manganese(II) Salts of 4-Aminobenzoic Acid Supported on Silica Gel. Monatshefte f�r Chemie / Chemical Monthly, 135(1), 41-43. doi:10.1007/s00706-003-0102-5Cervilla, A., Corma, A., Fornes, V., Llopis, E., Palanca, P., Rey, F., & Ribera, A. (1994). Intercalation of [MoVIO2(O2CC(S)Ph2)2]2- in a Zn(II)-Al(III) Layered Double Hydroxide Host: A Strategy for the Heterogeneous Catalysis of the Air Oxidation of Thiols. Journal of the American Chemical Society, 116(4), 1595-1596. doi:10.1021/ja00083a065Saxena, A., Kumar, A., & Mozumdar, S. (2007). Ni-nanoparticles: An efficient green catalyst for chemo-selective oxidative coupling of thiols. Journal of Molecular Catalysis A: Chemical, 269(1-2), 35-40. doi:10.1016/j.molcata.2006.12.042Corma, A., Leyva-Pérez, A., & Sabater, M. J. (2011). Gold-Catalyzed Carbon−Heteroatom Bond-Forming Reactions. Chemical Reviews, 111(3), 1657-1712. doi:10.1021/cr100414uArcadi, A. (2008). Alternative Synthetic Methods through New Developments in Catalysis by Gold. Chemical Reviews, 108(8), 3266-3325. doi:10.1021/cr068435dHashmi, A. S. K. (2007). Gold-Catalyzed Organic Reactions. Chemical Reviews, 107(7), 3180-3211. doi:10.1021/cr000436xGorin, D. J., Sherry, B. D., & Toste, F. D. (2008). Ligand Effects in Homogeneous Au Catalysis. Chemical Reviews, 108(8), 3351-3378. doi:10.1021/cr068430gFürstner, A. (2009). Gold and platinum catalysis—a convenient tool for generating molecular complexity. Chemical Society Reviews, 38(11), 3208. doi:10.1039/b816696jShen, H. C. (2008). Recent advances in syntheses of heterocycles and carbocycles via homogeneous gold catalysis. Part 1: Heteroatom addition and hydroarylation reactions of alkynes, allenes, and alkenes. Tetrahedron, 64(18), 3885-3903. doi:10.1016/j.tet.2008.01.081Hashmi, A. S. K., & Rudolph, M. (2008). Gold catalysis in total synthesis. Chemical Society Reviews, 37(9), 1766. doi:10.1039/b615629kMuzart, J. (2008). Gold-catalysed reactions of alcohols: isomerisation, inter- and intramolecular reactions leading to C–C and C–heteroatom bonds. Tetrahedron, 64(25), 5815-5849. doi:10.1016/j.tet.2008.04.018Hutchings, G. J. (2008). Supported gold and gold palladium catalysts for selective chemical synthesis. Catalysis Today, 138(1-2), 9-14. doi:10.1016/j.cattod.2008.04.029Widenhoefer, R. A., & Han, X. (2006). Gold-Catalyzed Hydroamination of C–C Multiple Bonds. European Journal of Organic Chemistry, 2006(20), 4555-4563. doi:10.1002/ejoc.200600399Haruta, M. (1997). Size- and support-dependency in the catalysis of gold. Catalysis Today, 36(1), 153-166. doi:10.1016/s0920-5861(96)00208-8Haruta, M. (1997). Catalysis Surveys from Japan, 1(1), 61-73. doi:10.1023/a:1019068728295A. Corma , H.Garcia, Supported gold nanoparticles as oxidation catalysts from Nanoparticles and Catalysis, 2008, 389. Editor: D. AstrucC. Della Pina , E.Falletta, M.Rossi, Gold nanoparticles-catalyzed oxidations in organic chemistry, ibid, p. 427C. Louis , Gold nanoparticles: recent advances in CO oxidation, ibid, pp. 475–503Carrettin, S., Concepción, P., Corma, A., López Nieto, J. M., & Puntes, V. F. (2004). Nanocrystalline CeO2 Increases the Activity of Au for CO Oxidation by Two Orders of Magnitude. 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Gender differences in beliefs about health:A comparative qualitative study with Ghanaian and Indian migrants living in the United Kingdom

Background There is a well-established association between migration to high income countries and health status, with some groups reporting poorer health outcomes than the host population. However, processes that influence health behaviours and health outcomes across minority ethnic groups are complex and in addition, culture ascribes specific gender roles for men and women, which can further influence perspectives of health. The aim of this study was to undertake a comparative exploration of beliefs of health among male and female Ghanaian and Indian migrants and White British participants residing in an urban area within the UK. Methods Thirty-six participants (12 each Ghanaian, Indian and White British) were recruited through community settings and participated in a semi-structured interview focusing on participant’s daily life in the UK, perceptions of their own health and how they maintained their health. Interviews were analyzed using a Framework approach. Results Three super ordinate themes were identified and labelled (a) beliefs about health; (b) symptom interpretation and (c) self-management and help seeking. Gender differences in beliefs and health behaviour practices were apparent across participants. Conclusions This is the first study to undertake a comparative exploration of health beliefs among people who have migrated to the UK from Ghana and India and to compare with a local (White British) population. The results highlight a need to consider both cultural and gender-based diversity in guiding health behaviours, and such information will be useful in the development of interventions to support health outcomes among migrant populations

Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types

Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment

Royal and Lordly Residence in Scotland c 1050 to c 1250: an Historiographical Review and Critical Revision

Academic study of eleventh to thirteenth century high status residence in Scotland has been largely bypassed by the English debates over origin, function and symbolism. Archaeologists have also been slow to engage with three decades of historical revision of traditional socio-economic, cultural and political models upon which their interpretations of royal and lordly residence have drawn. Scottish castle-studies of the pre-1250 era continue to be framed by a ‘military architecture’ historiographical tradition and a view of the castle as an alien artefact imposed on the land by foreign adventurers and a ‘modernising’ monarchy and native Gaelic nobility. Knowledge and understanding of pre-twelfth century native high status sites is rudimentary and derived primarily from often inappropriate analogy with English examples. Discussion of native responses to the imported castle-building culture is founded upon retrospective projection of inappropriate later medieval social and economic models and anachronistic perceptions of military colonialism. Cultural and socio-economic difference is rarely recognised in archaeological modelling and cultural determinism has distorted perceptions of structural form, social status and material values. A programme of interdisciplinary studies focused on specific sites is necessary to provide a corrective to this current situation