Geochemistry of carbon at DSDP Legs 58 and 59 Holes

I obtained 68 quarter sections of cores from the JOIDES Organic Geochemistry Panel for studying type, distribution, and stages of organic diagenesis of sedimentary organic matter in the West Philippine and Parece Vela basins and Mariana Trough area (Figure 1). The present chapter compares (1) 11 geochemical parameters used to determine organic source and its stage of genesis within the 9 site locations in this study area and (2) compares these 11 with the same parameters reported from Leg 56, outer trench slope of the Japan Trench, and Leg 60, Mariana Trough and Trench (Schorno, in press a, b). Even though these sediments are considered pelagic, the organic content in most of the core sections appears to be hemipelagic. The sedimentary organic matter in these cores is believed to be in an early stage of diagenesis. Both conclusions are based primarily on the fl-alkane distribution within the organic matter. This particular parameter, I note later, has a major weakness. As Hunt (Hunt, 1979) and I (in press b) observed, marine organisms synthesize /z-alkanes with distributions containing neither odd nor even preferences. Thus those sediments that did contain w-alkane distributions with OEP near 1, suggesting a late stage of catagenesis, may in actuality be immature marine sediments.

Geochemistry of ODP Hole 176-735B igneous and hydrothermal veins

During Legs 118 and 176, Ocean Drilling Program Hole 735B, located on Atlantis Bank on the Southwest Indian Ridge, was drilled to a total depth of 1508 meters below seafloor (mbsf) with nearly 87% recovery. The recovered core provides a unique section of oceanic Layer 3 produced at an ultraslow spreading ridge. Metamorphism and alteration are extensive in the section but decrease markedly downward. Both magmatic and hydrothermal veins are present in the core, and these were active conduits for melt and fluid in the crust. We have identified seven major types of veins in the core: felsic and plagioclase rich, plagioclase + amphibole, amphibole, diopside and diopside + plagioclase, smectite ± prehnite ± carbonate, zeolite ± prehnite ± carbonate, and carbonate. A few epidote and chlorite veins are also present but are volumetrically insignificant. Amphibole veins are most abundant in the upper 50 m of the core and disappear entirely below 520 mbsf. Felsic and plagioclase ± amphibole ± diopside veins dominate between ~50 and 800 mbsf, and low-temperature smectite, zeolite, and prehnite veins are present in the lower 500 m of the core. Carbonate veinlets are randomly present throughout the core but are most abundant in the lower portions. The amphibole veins are closely associated with zones of intense crystal plastic deformation formed at the brittle/ductile boundary at temperatures above 700°C. The felsic and plagioclase-rich veins were formed originally by late magmatic fluids at temperatures above 800°C, but nearly all of these have been overprinted by intense hydrothermal alteration at temperatures between 300° and 600°C. The zeolite, prehnite, and smectite veins formed at temperatures <100°C. The chemistry of the felsic veins closely reflects their dominant minerals, chiefly plagioclase and amphibole. The plagioclase is highly zoned with cores of calcic andesine and rims of sodic oligoclase or albite. In the felsic veins the amphibole ranges from magnesio-hornblende to actinolite or ferro-actinolite, whereas in the monomineralic amphibole veins it is largely edenite and magnesio-hornblende. Diopside has a very narrow range of composition but does exhibit some zoning in Fe and Mg. The felsic and plagioclase-rich veins were originally intruded during brittle fracture at the ridge crest. The monomineralic amphibole veins also formed near the ridge axis during detachment faulting at a time of low magmatic activity. The overprinting of the igneous veins and the formation of the hydrothermal veins occurred as the crustal section migrated across the floor of the rift valley over a period of ~500,000 yr. The late-stage, low-temperature veins were deposited as the section migrated out of the rift valley and into the transverse ridge along the margin of the fracture zone.

(Table 1) Chemical composition of segregations and groundmass seperates of ODP Leg 135 samples

Concentrations of dark-colored, highly vesicular, quench-textured mesostasis occur commonly in volcanic rocks drilled in the Lau Basin during Leg 135. These segregations occur as veins, patches, and vesicle linings in rocks with 49%-54% SiO2. The segregations are depleted in Mg, Ca, Al, Sc, Ni, and Cr and enriched in Ti, Ba, Y, and Zr compared to the groundmass with which they occur. Many of the segregations are unusually enriched in copper. The elemental variations show that the segregations are residual liquids produced by 12%-55% crystallization of plagioclase and clinopyroxene, with minor olivine, opaques, or orthopyroxene from the groundmass melt. The liquids forming the segregations are mobilized and emplaced in earlier formed vesicles during the rapid crystallization of the groundmass. The dominant process in this mobilization and emplacement is volatile exsolution from crystallizing melts constrained by a rigid crystalline framework. This exsolution produces significant overpressures within the late-stage melts; the overpressure drives the residual melts through the walls of the older vesicles, along planes of weakness, and into voids. This mechanism is consistent with the occurrence of bimodal vesicle populations in many of the host lavas.

Geochemistry of lower sheeted dike complex samples of ODP Holes 137-504B and 140-504B

Rocks of the lower sheeted dike complex of Hole 504B sampled during Leg 140 were analyzed for major and trace element compositions to investigate the effects of igneous processes and hydrothermal alteration on the compositions of the rocks. The rocks are relatively uniform in composition and similar to the shallower dikes. They are moderately evolved mid-ocean-ridge basalts (MORB) with relatively high MgO (7.9-10 wt%) and Mg# (0.60-0.70), and have unusually low incompatible element contents (TiO2 = 0.42-1.1 wt%, Zr = 23-62 ppm). Discrete compositional intervals in the hole reflect varying degrees of differentiation, and olivine and plagioclase accumulation in the rocks, and may be related to injection of packets of dikes having similar compositions. Systematic depletions of total REE, Zr, Y, TiO2, and P2O5 in centimeter-size patches are most likely attributed to exclusion of highly differentiated, late-stage interstitial liquids from small portions of the rocks. The rocks exhibit increased H2O+ reflecting hydrothermal alteration. Replacement of primary plagioclase by albite and oligoclase led to local gains of Na2O, losses of CaO, and slightly positive Eu anomalies. Some mobility of P2O5 led to minor increases and decreases in P2O5 contents, and some local mobility of Ti may have occurred during alteration of titanomagnetite to titanite. Higher temperatures of alteration in the lower sheeted dikes led to breakdown of pyroxene and sulfide minerals and losses of Zn, Cu, and S to hydrothermal fluids. Later addition of anhydrite to the rocks in microfractures and replacing plagioclase caused local increases in sulfur contents. The lower sheeted dikes are a major source of metals to hydrothermal fluids for the formation of metal sulfide deposits on and within the seafloor.

Geochemistry of sheeted dike complex minerals of ODP Hole 140-504B

Diabases were recovered during Legs 137 and 140 at Hole 504B from depths between 1621.5 and 2000.4 meters below seafloor in the lower sheeted dike complex. The samples contain multiple generations of millimetric to centimetric veins. The orientation of the measured veins suggests that two main vein sets exist: one characterized by shallow dipping and the other by random trend. Thermal contraction during rock cooling is considered the main mechanism responsible for fracture formation. Vein infill is related to the circulation of hydrothermal fluids near the spreading axis. Some veins are surrounded by millimeter-sized alteration halos due to fluid percolation from the fractures through the host rock. Vein-filling minerals are essentially amphibole, chlorite, and zeolites. Amphibole composition is controlled by the microstructural site of the rock. Actinolite is the main amphibole occurring in the veins and also in the groundmass away from the halos. In the alteration halos, amphibole shows composition of actinolitic hornblende and Mg-hornblende. Late-stage tension gashes and interstitial spaces in some amphibole-bearing veins are filled with zeolites, suggesting that the veins likely suffered multiple opening stages that record the cooling history of the circulating fluids. Evidence of deformation recorded by the recovered samples seems to be restricted to veins that clearly represent elements of weakness of the rock. On the basis of vein geometry and microstructure we infer structural interpretations for the formation mechanism and for deformation of veins.

Seawater carbonate chemistry, mass, length and gene expression of Sepia officinalis during experiments, 2011

The specific transporters involved in maintenance of blood pH homeostasis in cephalopod molluscs have not been identified to date. Using in situ hybridization and immuno histochemical methods, we demonstrate that Na+/K+-ATPase (soNKA), a V-type H+-ATPase (soV-HA), and Na+/HCO3- cotransporter (soNBC) are co-localized in NKA-rich cells in the gills of Sepia officinalis. mRNA expression patterns of these transporters and selected metabolic genes were examined in response to moderately elevated seawater pCO2 (0.16 and 0.35 kPa) over a time-course of six weeks in different ontogenetic stages. The applied CO2 concentrations are relevant for ocean acidification scenarios projected for the coming decades. We determined strong expression changes in late stage embryos and hatchlings, with one to three log2-fold reductions in soNKA, soNBCe, socCAII and COX. In contrast, no hypercapnia induced changes in mRNA expression were observed in juveniles during both short- and long-term exposure. However a transiently increased demand of ion regulatory demand was evident during the initial acclimation reaction to elevated seawater pCO2. Gill Na+/K+-ATPase activity and protein concentration were increased by approximately 15% in during short (2-11 day), but not long term (42 day) exposure. Our findings support the hypothesis that the energy budget of adult cephalopods is not significantly compromised during long-term exposure to moderate environmental hypercapnia. However, the down regulation of ion-regulatory and metabolic genes in late stage embryos, taken together with a significant reduction in somatic growth, indicates that cephalopod early life stages are challenged by elevated seawater pCO2.

Digital anthropology and educational eGames: learning through behavioural patterns in digital, game-based contexts

The selected publications are focused on the relations between users, eGames and the educational context, and how they interact together, so that both learning and user performance are improved through feedback provision. A key part of this analysis is the identification of behavioural, anthropological patterns, so that users can be clustered based on their actions, and the steps taken in the system (e.g. social network, online community, or virtual campus). In doing so, we can analyse large data sets of information made by a broad user sample,which will provide more accurate statistical reports and readings. Furthermore, this research is focused on how users can be clustered based on individual and group behaviour, so that a personalized support through feedback is provided, and the personal learning process is improved as well as the group interaction. We take inputs from every person and from the group they belong to, cluster the contributions, find behavioural patterns and provide personalized feedback to the individual and the group, based on personal and group findings. And we do all this in the context of educational games integrated in learning communities and learning management systems. To carry out this research we design a set of research questions along the 10-year published work presented in this thesis. We ask if the users can be clustered together based on the inputs provided by them and their groups; if and how these data are useful to improve the learner performance and the group interaction; if and how feedback becomes a useful tool for such pedagogical goal; if and how eGames become a powerful context to deploy the pedagogical methodology and the various research methods and activities that make use of that feedback to encourage learning and interaction; if and how a game design and a learning design must be defined and implemented to achieve these objectives, and to facilitate the productive authoring and integration of eGames in pedagogical contexts and frameworks. We conclude that educational games are a resourceful tool to provide a user experience towards a better personalized learning performance and an enhance group interaction along the way. To do so, eGames, while integrated in an educational context, must follow a specific set of user and technical requirements, so that the playful context supports the pedagogical model underneath. We also conclude that, while playing, users can be clustered based on their personal behaviour and interaction with others, thanks to the pattern identification. Based on this information, a set of recommendations are provided Digital Anthropology and educational eGames 6 /216 to the user and the group in the form of personalized feedback, timely managed for an optimum impact on learning performance and group interaction level. In this research, Digital Anthropology is introduced as a concept at a late stage to provide a backbone across various academic fields including: Social Science, Cognitive Science, Behavioural Science, Educational games and, of course, Technology-enhance learning. Although just recently described as an evolution of traditional anthropology, this approach to digital behaviour and social structure facilitates the understanding amongst fields and a comprehensive view towards a combined approach. This research takes forward the already existing work and published research onusers and eGames for learning, and turns the focus onto the next step — the clustering of users based on their behaviour and offering proper, personalized feedback to the user based on that clustering, rather than just on isolated inputs from every user. Indeed, this pattern recognition in the described context of eGames in educational contexts, and towards the presented aim of personalized counselling to the user and the group through feedback, is something that has not been accomplished before.

Alteration mineralogy and pathfinder element inventory of the McArthur River unconformity-related uranium deposit, Canada

The chemical compositions, modal mineralogy, and textural variability of interstitial minerals in sandstones of the Athabasca Group strata in the vicinity of the McArthur River unconformity-related uranium deposit were characterized using a combination of short wave infrared spectroscopy (SWIR), lithogeochemistry, scanning electron microscopy (SEM), electron probe microanalysis (EPMA) and laser ablation mass spectrometry (LA-ICP-MS) to determine the residence sites of pathfinder trace elements. The importance of integrating in-situ mineral chemistry with whole-rock analyses resides in the possibility to establish the mineralogical and paragenetic context of geochemical signatures in defining the footprint of the deposit. Located in the Athabasca Basin, Saskatchewan, Canada, the deposit is situated below ~550 m of quartz arenitic sandstones that are strongly silicified between depths of approximately 200-400 m. The silicified layer exhibits significant control on the distribution of alteration minerals, and appears to have restricted both the primary and secondary dispersion of pathfinder trace elements, which include U, radiogenic Pb isotopes, V, Ni, Co, Cu, Mo, As, Zn, and REEs. Diagenetic background sandstones contain assemblages of illite, dickite, aluminum-phosphate-sulfate (APS) minerals, apatite, and Fe-Ti oxide minerals. Altered sandstones contain assemblages of Al-Mg chlorite (sudoite), alkali-deficient dravite, APS minerals, kaolinite, illite, and oxide minerals. Throughout the sandstones, APS minerals account for the majority of the Sr and LREE concentrations, whereas late pre-ore chlorite, containing up to 0.1 wt.% Ni, accounts for the majority of Ni concentrations. Cobalt, Cu, Mo, and Zn occur predominantly in cryptic sub-micron sulfide and sulfarsenide inclusions in clay mineral aggregates and in association with paragenetically-late Fe-Ti oxides. Uranium occurs predominantly in cryptic micro-inclusions associated with pyrite in late-stage quartz overgrowths, and with paragenetically late Fe-Ti oxide micro-inclusions in kaolinite. Additionally, up to 0.2 wt.% U is cryptically distributed in post-ore Fe-oxide veins. Early diagenetic apatite, monazite and apatite inclusions in detrital quartz, and detrital zircon also contribute significant U and HREE to samples analyzed with an aggressive leach such as Aqua Regia. Detailed LA-ICP-MS chemical mapping of interstitial assemblages, detrital grains, and cements provides new insights into the distribution and inventory of pathfinder elements in the footprint of the McArthur River uranium deposit.

Acceptance of relapse fears in breast cancer patients: effects of an act-based abridged intervention

Objective: Relapse fear is a common psychological scar in cancer survivors. The aim of this study is to assess the effects of an abridged version of Acceptance and Commitment Therapy (ACT) in breast cancer patients.Method: An open trial was developed with 12 non-metastatic breast cancer patients assigned to 2 conditions, ACT and waiting list. Interventions were applied in just one session and focused on the acceptance of relapse fears through a ‘defusion’ exercise. Interference and intensity of fear measured through subjective scales were collected after each intervention and again 3 months later. Distress, hypochondria and ‘anxious preocupation’ were also evaluated through standardized questionnaires.Results: The analysis revealed that ‘defusion’ contributed to decrease the interference of the fear of recurrence, and these changes were maintained three months after intervention in most subjects. 87% of participants showed clinically significant decreases in interference at follow-up sessions whereas no patient in the waiting list showed such changes. Statistical analysis revealed that the changes in interference were significant when comparing pre, post and follow-up treatment, and also when comparing ACT and waiting list groups. Changes in intensity of fear, distress, anxious preoccupation and hypochondria were also observed.Conclusions: Exposure through ‘defusion’ techniques might be considered a useful option for treatment of persistent fears in cancer patients. This study provides evidence for therapies focusing on psychological acceptance in cancer patients through short, simple and feasible therapeutic methods.

Retinal nerve fiber layer analysis using GDx® in 49 patients with chronic phase DUSN

To describe retinal nerve fiber layer changes in late-stage diffuse unilateral subacute neuroretinitis eyes and compare these results with healthy eyes observed through nerve fiber analyzer (GDx®). Methods: This is a retrospective case-control study in which 49 eyes in late-stage diffuse unilateral subacute neuroretinitis were examined from May/97 to December/ 01. First, eyes with diffuse unilateral subacute neuroretinitis and healthy contralateral eyes (Control Group I) were statistically matched. Subsequently, eyes with diffuse unilateral subacute neuroretinitis were compared with eyes of healthy patients (Control Group II). Results: Eyes from Control Groups I and II had higher relative frequency of “within normal limits” status. Eyes from the diffuse unilateral subacute neuroretinitis (DUSN) Group had higher frequency of “outside normal limits” and “borderline” status. Control Groups I and II had absolute values different from the DUSN Group regarding all parameters (p<0.05), except for Symmetry in Control Groups I and II, Average thickness and Superior Integral in control group II. Conclusion: Patients with late-stage diffuse unilateral subacute neuroretinitis presented presumed decrease in nerve fiber layer thickness shown by GDx®. Retinal zones with larger vascular support and larger amount of nerve fibers presented higher decrease in the delay of the reflected light measured by the nerve fiber analyzer

A Qualitative Assessment of Breast Cancer Advocates in Bolivia, Colombia, Ecuador and Peru

Thesis (Master's)--University of Washington, 2016-06

Dynamic Link Inclusion in Online PDF Journals

Two complementary de facto standards for the publication of electronic documents are HTML on theWorldWideWeb and Adobe s PDF (Portable Document Format) language for use with Acrobat viewers. Both these formats provide support for hypertext features to be embedded within documents. We present a method, which allows links and other hypertext material to be kept in an abstract form in separate link databases. The links can then be interpreted or compiled at any stage and applied, in the correct format to some specific representation such as HTML or PDF. This approach is of great value in keeping hyperlinks relevant, up-to-date and in a form which is independent of the finally delivered electronic document format. Four models are discussed for allowing publishers to insert links into documents at a late stage. The techniques discussed have been implemented using a combination of Acrobat plug-ins, Web servers and Web browsers.

Retinal nerve fiber layer analysis using GDx® in 49 patients with chronic phase DUSN

To describe retinal nerve fiber layer changes in late-stage diffuse unilateral subacute neuroretinitis eyes and compare these results with healthy eyes observed through nerve fiber analyzer (GDx®). Methods: This is a retrospective case-control study in which 49 eyes in late-stage diffuse unilateral subacute neuroretinitis were examined from May/97 to December/ 01. First, eyes with diffuse unilateral subacute neuroretinitis and healthy contralateral eyes (Control Group I) were statistically matched. Subsequently, eyes with diffuse unilateral subacute neuroretinitis were compared with eyes of healthy patients (Control Group II). Results: Eyes from Control Groups I and II had higher relative frequency of “within normal limits” status. Eyes from the diffuse unilateral subacute neuroretinitis (DUSN) Group had higher frequency of “outside normal limits” and “borderline” status. Control Groups I and II had absolute values different from the DUSN Group regarding all parameters (p<0.05), except for Symmetry in Control Groups I and II, Average thickness and Superior Integral in control group II. Conclusion: Patients with late-stage diffuse unilateral subacute neuroretinitis presented presumed decrease in nerve fiber layer thickness shown by GDx®. Retinal zones with larger vascular support and larger amount of nerve fibers presented higher decrease in the delay of the reflected light measured by the nerve fiber analyzer

Geologia, petrologia, geocronologia e mineralizações sulfetadas do complexo ézio, província mineral de carajás, Brasil

Dissertação (mestrado)—Universidade de Brasília, Instituto de Geociências, Pós-Graduação em Geologia, 2015.