Micromorphology and spectroscopic characteristics of organic matter in waterlogged podzols of the upper Amazon basin

In waterlogged environments of the upper Amazon basin, organic matter is a major driver in the podzolisation of clay-depleted laterites, especially through its ability to weather clay minerals and chelate metals. Its structure in eight organic-rich samples collected at the margin and in the centre of the podzolic area of a soil sequence was investigated. The samples illustrate the main steps in the development of waterlogged podzols and belong either to eluviated topsoil A horizons or to illuviated subsoil Bhs, Bh and 2BCs horizons. Organic matter micromorphology was described, and the overall molecular structure of their clay size fractions was assessed using Fourier transform infrared (FTIR) spectroscopy and cross polarization/magic angle spinning (CP/MAS) C-13 nuclear magnetic resonance (NMR). Organic features of the horizons strongly vary both vertically and laterally in the sequence. Topsoil A horizons are dominated by organic residues juxtaposed to clean sands with a major aliphatic contribution. In the subsoil, numerous coatings, characteristic of illuviation processes, are observed in the following horizons: (i) At the margin and bottom parts of the podzolic area, dark brown organic compounds of low aromacity with abundant oxygen-containing groups accumulate in Bhs and 2BCs horizons. Their spectroscopic features agree with the observation of cracked coatings in 2BCs and the presence of organometallic complexes, whose abundance decreases towards low lying positions. (ii) By contrast, black organic compounds of high aromacity with few chelating functions accumulate as coatings and infills in the overlying sandy Bh horizon of well-expressed waterlogged podzols. (c) 2008 Elsevier B.V. All rights reserved.

Attitude stabilization of a rigid spacecraft in the geomagnetic field

An analytical method is proposed to study the attitude stability of a triaxial spacecraft moving in a circular Keplerian orbit in the geomagnetic field. The method is developed based on the electrodynamics effect of the influence of the Lorentz force acting on the charged spacecraft's surface. We assume that the rigid spacecraft is equipped with an electrostatic charged protective shield, having an intrinsic magnetic moment. The main elements of this shield are an electrostatic charged cylindrical screen surrounding the protected volume of the spacecraft. The rotational motion of the spacecraft about its centre of mass due to torques from gravitational force, as well Lorentz and magnetic forces is investigated. The equilibrium positions of the spacecraft in the orbital coordinate system are obtained. The necessary and sufficient conditions for the stability of the spacecraft's equilibrium positions are constructed using Lyapunov's direct method. The numerical results have shown that the Lorentz force has a significant influence on the stability of the equilibrium positions, which can affect the attitude stabilization of the spacecraft. (C) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.

Blue cooperative luminescence in Yb3+-doped tellurite glasses excited at 1.064 mu m

Blue luminescence emission around 480 nm through cooperative upconversion from pairs of Yb3+ ions implanted into 60TeO(2)-10GeO(2)-10K(2)O-10Li(2)O-10Nb(2)O(5) tellurite glasses and excited by a cw laser at 1.064 mum is demonstrated. Cooperative luminescence emission enhancement owing to the temperature dependent multiphonon-assisted anti-Stokes excitation process of the ytterbium ions is also observed. The experimental results revealed a fourfold enhancement in the cooperative luminescence emission when the sample was heated in the temperature range of 20 degreesC-260 degreesC. The thermally induced enhancement is assigned to the effective absorption cross-section for the ytterbium ions which is an increasing function of the medium temperature. (C) 2002 American Institute of Physics.

Mesozoic tectonic evolution of the south Orkney microcontinent, Scotia arc, Antarctica

The South Orkney Islands are the exposed part of a continental fragment on the southern limb of the Scotia are. The islands are to a large extent composed of metapelites and metagreywackes of probable Triassic sedimentary age. Deformation related to an accretionary wedge setting, with associated metamorphism from anchizone to the greenschist facies, are of Jurassic age (176-200 Ma). on Powell Island, in the centre of the archipelago, five phases of deformation are recognized. The first three, associated with the main metamorphism, are tentatively correlated with early Jurassic subduction along the Pacific margin of Gondwana. D-4 is a phase of middle to late Jurassic crustal extension associated with uplift. This extension phase may be related to opening of the Rocas Verdes basin in southern Chile, associated with the breakup of Gondwanaland. Upper Jurassic conglomerates cover the metamorphic rocks unconformably. D-5 is a phase of brittle extensional faulting probably associated with Cenozoic opening of the Powell basin west of the archipelago, and with development of the Scotia are.

Vascular organization of the hystricomorph placenta: a comparative study in the Agouti, capybara, guinea pig, paca and rock cavy

The placental vasculature of five hystricomorph rodents was examined by latex injection of the blood vessels, immunohistochemistry and scanning electron microscopy of vessel casts. The pattern of branching of the vessels is described at the level of fine structure. The placenta is divided into lobes separated by interlobular trophoblast. Fetal arteries course through the interlobular areas and give rise to capillaries from which blood drains into veins at the centre of the lobes. Maternal blood reaches the placenta through spiral arteries that pass around the perimeter of the subplacenta. They supply large maternal blood sinuses, lined by trophoblast, which run through the interlobular areas and into the centre of the lobes. Here they supply fine channels that run parallel to the fetal capillaries, so that maternal blood flows from the centre of the lobe to the periphery. This arrangement provides the morphological basis for countercurrent exchange. The maternal channels of the labyrinth drain into spaces formed by the latticework of the interlobular trophoblast and thence through venous lacunae to a basal venous lacunar ring. The subplacenta is supplied by a single fetal artery. The vessels within the subplacenta pursue a tortuous course with dilatations and constrictions as in an endocrine gland. (C) 2003 Elsevier Ltd. All rights reserved.

Electronic spectra, ESR and crystal structure of tetrahedral halocuprates(II). The existence of cations (2tbpo·H+) with a very short hydrogen bond

Two compounds [2tbpo·H+)2[CuCl4]= (yellow) and (2tbpo·H+)2[CuBr4]= (dark purple) (tbpo = tribenzylphosphine oxide) have been prepared and investigated by means of crystal structure, electronic, vibrational and ESR spectra. The crystal structure of the (2tbpo·H+)2[CuCl4]= complex was determined by three-dimensional X-ray diffraction. The compound crystallizes in the space group P42/n with unit-cell dimensions a = 19.585(2), c = 9.883(1)Å, V = 3790 (1)Å3, Z = 2, Dm = 1.303 (flotation) Dx = 1.302 Mg m-3. The structure was solved by direct methods and refined by blocked full-matrix least-squares to R = 0.053 for 2583 observed reflections. Cu(II) is coordinated to four chlorides in a tetrahedral arrangement. Tribenzylphosphine oxide molecules, related by a centre of inversion, are connected by a short hydrogen bridge. Chemical analysis, electronic and vibrational spectra showed that the bromide compound is similar to the chloride one and can be formulated as (2tbpo·H+)2[CuBr4]=. The position of the dd transition bands, the charge transfer bands, the ESR and the vibrational spectra of both complexes are discussed. The results are compared with analogous complexes cited in the literature. © 1983.

Economic Survey of Latin America and the Caribbean 2008-2009: Policies for creating quality jobs

Includes bibliography

Measurement of the underlying event activity in pp collisions at √s = 0.9 and 7 TeV with the novel jet-area/median approach

The first measurement of the charged component of the underlying event using the novel jet-area/median approach is presented for proton-proton collisions at centre-of-mass energies of 0.9 and 7 TeV. The data were recorded in 2010 with the CMS experiment at the LHC. A new observable, sensitive to soft particle production, is introduced and investigated inclusively and as a function of the event scale defined by the transverse momentum of the leading jet. Various phenomenological models are compared to data, with and without corrections for detector effects. None of the examined models describe the data satisfactorily. © 2012 SISSA.

Studies of jet quenching using isolated-photon+jet correlations in PbPb and pp collisions at sNN=2.76TeV

Results from the first study of isolated-photon+jet correlations in relativistic heavy ion collisions are reported. The analysis uses data from PbPb collisions at a centre-of-mass energy of 2.76TeV per nucleon pair corresponding to an integrated luminosity of 150μb-1 recorded by the CMS experiment at the LHC. For events containing an isolated photon with transverse momentum pTγ>60GeV/c and an associated jet with pTJet>30GeV/c, the photon+jet pT imbalance is studied as a function of collision centrality and compared to pp data and pythia calculations at the same collision energy. Using the pTγ of the isolated photon as an estimate of the momentum of the associated parton at production, this measurement allows an unbiased characterisation of the in-medium parton energy loss. For more central PbPb collisions, a significant decrease in the ratio pTJet/pTγ relative to that in the pythia reference is observed. Furthermore, significantly more pTγ>60GeV/c photons in PbPb are observed not to have an associated pTJet>30GeV/c jet, compared to the reference. However, no significant broadening of the photon+jet azimuthal correlation is observed. © 2012 CERN.

Measurement of differential top-quark-pair production cross sections in pp collisions at √s = 7TeV

Normalised differential top-quark-pair production cross sections are measured in pp collisions at a centre-of-mass energy of 7 TeVat the LHC with the CMS detector using data recorded in 2011 corresponding to an integrated luminosity of 5. 0 fb-1. The measurements are performed in the lepton+jets decay channels (e+jets and μ+jets) and the dilepton decay channels (e+}e-, μ+μ-, and μ±e∓). The tt̄ differential cross section is measured as a function of kinematic properties of the final-state charged leptons and jets associated to b quarks, as well as those of the top quarks and the tt̄ system. The data are compared with several predictions from perturbative QCD calculations up to approximate next-to-next-to-leading-order precision. No significant deviations from the standard model are observed. © 2013 CERN for the benefit of the CMS collaboration.

Measurement of the t̄t production cross section in the all-jet final state in pp collisions at √s=7 TeV

A measurement is presented of the t̄t production cross section σt̄t in proton-proton collisions at a centre-of-mass energy of 7 TeV, in the all-jet final state that contains at least six jets, two of which are tagged as originating from b quarks. The data correspond to an integrated luminosity of 3.54 fb-1, collected with the CMS detector at the LHC. The cross section is determined through an unbinned maximum likelihood fit of background and t̄t signal to the reconstructed mass spectrum of t̄t candidates in the data, in which events are subjected to a kinematic fit assuming a t̄t → W+bW-̄b → 6 jets hypothesis. The measurement yields σt̄t = 139±10(stat.)±26(syst.)±3(lum.)pb, a result consistent with those obtained in other t̄t decay channels, as well as with predictions of the standard model. © 2013 CERN for the benefit of the CMS collaboration.

Developments in relation to the proposal for securing the international recognition of the Caribbean sea as a special area in the context of sustainable development

Includes bibliography

Information and communication technology for disaster risk management in the Caribbean: subregional solutions to the challenge of limited human resource capacity

This document was adapted from a paper originally presented to the 8th Annual Caribbean Conference of Comprehensive Disaster Management, held in Montego Bay, Jamaica in December, 2013. It summarizes several activities that ECLAC has undertaken to assess the current state of information and communications technology (ICT) in the field of disaster risk management (DRM) as practiced in the Caribbean. These activities included an in-depth study that encompassed a survey of disaster management organizations in the region, an Expert Group Meeting attended by the heads of several national disaster offices, and a training workshop for professionals working in DRM in the Caribbean. One of the notable conclusions of ECLAC’s investigation on this topic is that the lack of human capacity is the single largest constraint that is faced in the implementation of ICT projects for DRM in the Caribbean. In considering strategies to address the challenge of limited human capacity at a regional level, two separate issues are recognized – the need to increase the ICT capabilities of disaster management professionals, and the need to make ICT specialists available to disaster management organizations to advise and assist in the implementation of technology-focused projects. To that end, two models are proposed to engage with this issue at a regional level. The first entails the establishment of a network of ICT trainers in the Caribbean to help DRM staff develop a strategic understanding of how technology can be used to further their organizational goals. The second is the development of “Centres of Excellence” for ICT in the Caribbean, which would enable the deployment of specialized ICT expertise to national disaster management offices on a project-by-project basis.

Socio-demographic analysis of youth in the Caribbean- a three country case study

Many Caribbean youth are doing reasonably well. They live in loving and caring families, attend school and are involved in various social activities in their communities. The health and well-being of the children and youth1 in the Caribbean is, and has been, the centre of attention of many studies, meetings and policy directives set at the regional, subregional and national levels. Programmes have been put in place to address the basic needs of young children in the areas of health and education and to provide guidance and directives to youth and adolescents in the area of professional formation and transition to adulthood. Critical issues such as reproductive health and family planning combined with access to education and information on these topics have been promoted to some extent. And finally, the Caribbean is known for rather high school enrolment rates in primary education that hardly show any gender disparities. While the situation is still good for some, growing numbers of children and youth cannot cope anymore with the challenges experienced quite early in their lives. Absent parents, instable care-taking arrangements, violence and aggression subjected to at home, in schools and among their friends, lack of a perspective in schools and the labour-market, early sexual initiation and teenage pregnancies are some of those issues faced by a rising number of young persons in this part of the world. Emotional instability, psychological stress and increased violence are one of the key triggers for increased violence and involvement in crime exhibited by ever younger youth and children. Further, the region is grappling with rising drop-out rates in secondary education, declining quality schooling in the classrooms and increasing numbers of students who leave school without formal certification. Youth unemployment in the formal labour market is high and improving the quality of professional formation along with the provision of adequate employment opportunities would be critical to enable youth to complete consistently and effectively the transition into adulthood and to take advantage of the opportunities to develop and use their human capital in the process. On a rather general note, the region does not suffer from a shortage of policies and programmes to address the very specific needs of children and youth, but the prominent and severe lack of systematic analysis and monitoring of the situation of children, youth and young families in the Caribbean does not allow for targeted and efficient interventions that promise successful outcomes on the long term. In an effort to assist interested governments to fill this analytical gap, various initiatives are underway to enhance data collection and their systematic analysis2. Population and household censuses are conducted every decade and a variety of household surveys, such as surveys of living conditions, labour force surveys and special surveys focusing on particular sub-groups of the population are conducted, dependent on the resources available, to a varying degree in the countries of the region. One such example is the United Nations Children’s Fund (UNICEF)-funded Multi-Indicator Cluster Surveys (MICS) that assess the situation of children and youth in a country. Over the past years and at present, UNICEF has launched a series of surveys in a number of countries in the Caribbean3. But more needs to be done to ensure that the data available is analyzed to provide the empirical background information for evidence-based policy formulation and monitoring of the efficiency and effectiveness of the efforts undertaken.

Review of CARIFORUM-EU EPA in development cooperation and WTO compatability

The Cotonou Agreement which succeeded the Lomé IV Agreement and was signed in Cotonou in June 2000 established a comprehensive framework to govern social, economic and political relations between the Africa, Caribbean, Pacific (ACP) grouping and the European Union (EU). At the centre of the partnership are objectives relating to economic development, the reduction and eventual eradication of poverty, and the smooth and gradual integration of ACP States into the world economy. In order to accomplish these objectives, the Cotonou Agreement provides for the conclusion between the ACP and the EU of “new World Trade Organization (WTO) compatible trading arrangements, removing progressively barriers to trade between them and enhancing cooperation in all areas relevant to trade” (Article 36.1). The conclusion of economic partnership agreements (EPAs) represented one way to achieve a WTO compatible instrument and had to be negotiated during the period starting from September 2002 until 31 December 2007 to replace the trade provisions of the Cotonou Agreement. After three and half years of negotiations, CARIFORUM and the European Commission (EC) finally concluded a comprehensive EPA with the EC on 16 December 2007 when an Agreement was initialed. The EPA Parties agreed to sign it later after a review of the provisions at both the national and regional levels. In CARIFORUM, various comments have been made from governments, Nongovernmental organizations (NGOs), the private sector and the labour movement about the strengths and weaknesses of the EPA. This review comes in this context and is confined to the development cooperation provisions and the question of WTO compatibility and consistency with the Doha Development Agenda (DDA) negotiations and existing WTO provisions on special and differential treatment.