946 resultados para Binary and ternary correlations
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Neogene biostratigraphic and magnetostratigraphic data are compiled from Holes 747A, 748B, and 751A drilled on the Southern Kerguelen Plateau during Ocean Drilling Program Leg 120. Neogene sections have excellent to good magnetostratigraphic signatures in many intervals. This, in addition to minimal coring gaps and the occurrence of mixed assemblages of both calcareous and siliceous microfossil assemblages, makes these valuable biostratigraphic reference sections for intra- and extraregional correlations. This paper combines the sequence of biostratigraphic events reported from diatom, radiolarian, planktonic foraminifer, calcareous nannofossil, and silicoflagellate studies of Leg 120 sediments. It correlates microfossil datums with the geomagnetic polarity time scale to test existing age estimates and to refine biostratigraphic age controls for the southern high latitudes. Significant biostratigraphic datums are presented in a series of age-depth plots. Numerous hiatuses are clearly identified through this approach, and the positions of lesser disconformities are suggested. Most Neogene intervals are represented in at least one site, although "regional" unconformities occur in the upper Pliocene, uppermost Miocene/lowermost Pliocene, middle upper Miocene, middle middle Miocene, and at the lower/middle Miocene boundaries. The longest hiatus spanned 6 m.y., with most other hiatuses representing 1 m.y. or less. This paper compiles Leg 120 biostratigraphic and magnetostratigraphic data for use in future syntheses of southern high latitude biostratigraphy and presents an age model for Leg 120 Neogene sediments.
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Based on the faunal record of planktonic foraminifers in three long gravity sediment cores from the eastern equatorial Atlantic, the sea-surface temperature history ove the last 750,000 years was studied at a resolution of 3,000 to 10,000 years. Detailed oxygen-isotope and paleomagnetic stratigraphy helped to identify the following major faunal events: Globorotaloides hexagonus and Globorotalia tumida flexuosa became extinct in the eastern tropical Atlantic at the isotope stage 4/5 boundary, now dated at 68,000 years B.P. The persistent occurrence of the pink variety of Globigerinoides ruber started during the late stage 12 at 410,000 years B.P. CARTUNE-age. This datum may provide an easily detectible faunal stratigraphic marker for the mid-Brunhes Chron. The updated scheme of the Ericson zones helped the recognition of a hiatus at the northwestern slope of the Sierra Leone Basin covering oxygen-isotope stages 10 to 12. Classifying the planktonic foraminifer counts into six faunal assemblages, according to the factor analysis derived model of Pflaumann (1985), the tropical and the tropical-upwelling communities account for 57 % at Site 16415, and 86 % at Site 13519, respectively of the variance of the faunal record. A largely continuous paleotemperature record for both winter and summer seasons was obtained from the top of the Sierra Leone Rise with the winter temperatures ranging between 20 and 25 °C, and the summer ones between 24 and 30 °C. The record of cores from greater water depths is frequently interrupted by samples with no-analogue faunal communities and/or poor preservation. Based on the seasonality signal, during cold periods the termal equator shifted to a geographically mnore asymmetrical northern position. Dissolution altering the faunal communities becomes stronger with greater water depth, the estimated mean minimum loss of specimens increases from 70 % to 80 % between 2,860 and 3,850 water depth although some species will be more susceptible than others. Enhanced dissolution occured during stage 4 but also during cold phases in the warm stage 7 and 9. Correlations between the Foraminiferal Dissolution Index and the estimated sea-surface temperatures are significant. Foraminiferal flux rates, negatively correlated to the flux rates of organic carbon and of diatoms, may be a result of enhanced dissolution during cold stages, destroying still more of the faunal signal than indicated by the calculated minimum loss. The fluctuations of the oxygen-isotope curves and the hibernal sea-surfave temperatures are fairly coherent. During warm oxygen-isotope stages the temperature maxima lag often by 5 to 15 ka behind the respective sotope minima. During cold stages, sea-surface temperature changes are partly out of phase and contain additional fluctuations.
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DSDP Leg 73 sediment cores allow direct calibrations of magnetostratigraphy and biostratigraphy for much of the latest Cretaceous to Cenozoic in the mid-latitude South Atlantic Ocean. A complete record of the Cenozoic was not obtained, however, because strong dissolution, poor core recovery and intense core disturbance have masked the biostratigraphy or magnetostratigraphy over some intervals of all recovered sections. DSDP Leg 73 results show the following correlations: Early/middle Miocene in Chron 16 Oligocene/Miocene within Subchron C6CN Eocene/Oligocene within Subchron C13R Middle/late Eocene top of Chron C17 Early/late Paleocene top of Subchron C27N Cretaceous/Tertiary within Subchron C29R
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The present work is aimed at discussing several issues related to the teamwork generic competence, motivational profiles and academic performance. In particular, we study the improvement of teamwork attitude, the predominant types of motivation in different contexts and some correlations among these three components of the learning process. The above-mentioned aspects are of great importance. Currently, the professional profile of engineers has a strong teamwork component and the motivational profile of students determines both their tendencies when they come to work as part of a team, as well as their performance at work. Taking these issues into consideration, we suggest four hypotheses: (H1) students improve their teamwork capacity through specific training and carrying out of a set of activities integrated into an active learning process; (H2) students with higher mastery motivation have a better attitude towards teamwork; (H3) students with different types of motivations reach different levels of academic performance; and (H4) students show different motivation profiles in different circumstances: type of courses, teaching methodologies, different times of the learning process. This study was carried out with Computer Science Engineering students from two Spanish universities. The first results point to an improvement in teamwork competence of students if they have previously received specific training in facets of that competence. Other results indicate that there is a correlation between the motivational profiles of students and their perception of teamwork competence. Finally, results point to a clear relationship between some kind of motivation and academic performance. In particular, four kinds of motivation are analyzed and students are classified into two groups according to them. After analyzing several marks obtained in compulsory courses, we perceive that those students that show higher motivation for avoiding failure obtain, in general, worse academic performance.
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Transcription factors control eukaryotic polymerase II function by influencing the recruitment of multiprotein complexes to promoters and their subsequent integrated function. The complexity of the functional ‘transcriptosome’ has necessitated biochemical fractionation and subsequent protein sequencing on a grand scale to identify individual components. As a consequence, much is now known of the basal transcription complex. In contrast, less is known about the complexes formed at distal promoter elements. The c-fos SRE, for example, is known to bind Serum Response Factor (SRF) and ternary complex factors such as Elk-1. Their interaction with other factors at the SRE is implied but, to date, none have been identified. Here we describe the use of mass-spectrometric sequencing to identify six proteins, SRF, Elk-1 and four novel proteins, captured on SRE duplexes linked to magnetic beads. This approach is generally applicable to the characterisation of nucleic acid-bound protein complexes and the post-translational modification of their components.
Nesting In The Clouds: Evaluating And Predicting Sea Turtle Nesting Beach Parameters From Lidar Data
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Humans' desire for knowledge regarding animal species and their interactions with the natural world have spurred centuries of studies. The relatively new development of remote sensing systems using satellite or aircraft-borne sensors has opened up a wide field of research, which unfortunately largely remains dependent on coarse-scale image spatial resolution, particularly for habitat modeling. For habitat-specialized species, such data may not be sufficient to successfully capture the nuances of their preferred areas. Of particular concern are those species for which topographic feature attributes are a main limiting factor for habitat use. Coarse spatial resolution data can smooth over details that may be essential for habitat characterization. Three studies focusing on sea turtle nesting beaches were completed to serve as an example of how topography can be a main deciding factor for certain species. Light Detection and Ranging (LiDAR) data were used to illustrate that fine spatial scale data can provide information not readily captured by either field work or coarser spatial scale sources. The variables extracted from the LiDAR data could successfully model nesting density for loggerhead (Caretta caretta), green (Chelonia mydas), and leatherback (Dermochelys coriacea) sea turtle species using morphological beach characteristics, highlight beach changes over time and their correlations with nesting success, and provide comparisons for nesting density models across large geographic areas. Comparisons between the LiDAR dataset and other digital elevation models (DEMs) confirmed that fine spatial scale data sources provide more similar habitat information than those with coarser spatial scales. Although these studies focused solely on sea turtles, the underlying principles are applicable for many other wildlife species whose range and behavior may be influenced by topographic features.
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The financial crisis that erupted in the eurozone not only affected the EU’s financial governance mechanisms, but also the very nature of state sovereignty and balances in the relations of member states; thus, the actual inequalities between the member states hidden behind their institutional equality have deteriorated. This transformation is recorded in the case law of the Court of Justice of the European Union and the member states’ constitutional courts, particularly in those at the heart of the crisis, with Greece as the most prominent example. It is the issue of public debt (sovereign debt) of the EU member states that particularly reflects the influence of the crisis on state sovereignty as well as the intensely transnational (intergovernmental) character of European integration, which under these circumstances takes the form of a continuous, tough negotiation. The historical connection between public debt (sovereign debt) and state sovereignty has re-emerged because of the financial crisis. This development has affected not only the European institutions, but also, at the member state level, the actual institutional content of the rule of law (especially judicial review) and the welfare state in its essence, as the great social and political acquis of 20th century Europe. From this perspective, the way that the Greek courts have dealt with the gradual waves of fiscal austerity measures and structural reforms from 2010 to 2015 is characteristic. The effect of the financial crisis on the sovereignty of the member states and on the pace of European integration also has an impact on European foreign and security policy, and the correlations between the political forces at both the national and European level, thus producing even more intense pressures on European social democracy. In light of the experience of the financial crisis, the final question is whether the nation state (given the large real inequalities among the EU member states) currently functions as a brake or as an engine for future European integration.
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Thyroid hormones are essential for normal growth and development and disruption of thyroid homeostasis can be critical to young developing individuals. The aim of the present study was to assess plasma concentrations of halogenated organic contaminants (HOCs) in chicks of two seabird species and to investigate possible correlations of HOCs with circulating thyroid hormone (TH) concentrations. Plasma from black-legged kittiwake (Rissa tridactyla) and northern fulmar (Fulmarus glacialis) chicks were sampled in Kongsfjorden, Svalbard in 2006. The samples were analyzed for thyroid hormones and a wide range of HOCs (polychlorinated biphenyls (PCBs), hydroxylated (OH-) and methylsulphoned (MeSO-) PCB metabolites, organochlorine pesticides (OCPs), brominated flame retardants (BFRs), and perfluorinated compounds (PFCs)). Concentrations of HOCs were generally low in kittiwake and fulmar chicks compared to previous reports. HOC concentrations were five times higher in fulmar chicks compared to in kittiwake chicks. PFCs dominated the summed HOCs concentrations in both species (77% in kittiwakes and 69% in fulmars). Positive associations between total thyroxin (TT4) and PFCs (PFHpS, PFOS, PFNA) were found in both species. Although correlations do not implicate causal relationships per se, the correlations are of concern as disruption of TH homeostasis may cause developmental effects in young birds.
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We have integrated Oligocene to lower upper Miocene planktonic foraminifer biostratigraphy with benthic foraminifer (Cibicidoides spp.) stable isotope records for two sites drilled on opposite sides of the Sierra Leone Rise in the eastern equatorial Atlantic Ocean. Deep Sea Drilling Project Site 366 (2853 m present water depth; 2200-2800 m paleodepth) recovered an Oligocene to upper Miocene record with a minor unconformity in the "middle" Oligocene and a condensed middle Miocene section. Ocean Drilling Program Site 667 (3529 m present depth; 3000-3500 m paleodepth) recovered an apparently continuous "middle" Oligocene to lower middle Miocene record and a similar condensed middle Miocene section. The Oligocene to lower Miocene sections were deposited at similar sedimentation rates (~11-16 m/m.y.). Stable isotope stratigraphy proved to be useful in establishing intra- and interbasinal correlations. In addition to the well-known earliest Oligocene and middle Miocene S180 increases, a distinct d18O increase occurred near the Oligocene/Miocene boundary. Carbon isotope variations provide similar potential for improving correlations; for example, a d13C increase occurred near the Oligocene/Miocene boundary in concert with increased d18O values. There was little d13C difference between the western Atlantic and eastern Atlantic basins during the late Oligocene and most of the middle Miocene; in contrast, eastern basin d13C values were slightly lower than those in the western basins during the earliest Oligocene (about 35-33 Ma) and early Miocene (about 22-18 Ma).
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Quantitative data on lower marine Phycomycetes (fungi) found in the upwelling waters off the West African coast during cruises No. 13 (1968), 19 (1970), 36 (1975) and 44 (1977) of R.V. "Meteor" are reported. The distribution of the total fungi numbers is presented and, as far as possible, the evaluation of the material up to species level is given. Several provisionally named forms and groups of morphologically related, undescribed fungi are included. A correlation between the number of fungi in sediments and the water depth and distance from the coast line is postulated. There are typical distributions of the lower marine fungi in water bodies and sediments. Different values within replicates of the stations in different years show that there is a sequence in development of fungal populations induced by changes in the water bodies. Surface water far from the coast has low numbers of fungi; numbers increase to a maximum nearer to the coast. In the vicinity of the coast the values decrease. The numbers of fungi in the deep sediments are low below 1,200 m. However, there are isolated areas of higher fungal activities, indicated by some deeper grab samples. During two cruises, the "overlying water" in the grab samples was investigated. It was evident that the numbers of fungi lost by stirring of the sediment when the grab was brought up to the surface were small, relatively and absolutely. The seamount "Josephine Bank" has been investigated for the first time with respect to lower marine fungi; the populations are low in the sediments, but one sample of the surface water had a higher number than the water in the surroundings. In some hydrographic series there was a peculiar depth distribution. An increase occurred at a depth greater than 1,000 m. The results are discussed and some correlations to the aging of the fungal populations in the water masses are constructed.
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The relative paleointensity (RPI) method assumes that the intensity of post depositional remanent magnetization (PDRM) depends exclusively on the magnetic field strength and the concentration of the magnetic carriers. Sedimentary remanence is regarded as an equilibrium state between aligning geomagnetic and randomizing interparticle forces. Just how strong these mechanical and electrostatic forces are, depends on many petrophysical factors related to mineralogy, particle size and shape of the matrix constituents. We therefore test the hypothesis that variations in sediment lithology modulate RPI records. For 90 selected Late Quaternary sediment samples from the subtropical and subantarctic South Atlantic Ocean a combined paleomagnetic and sedimentological dataset was established. Misleading alterations of the magnetic mineral fraction were detected by a routine Fe/kappa test (Funk, J., von Dobeneck, T., Reitz, A., 2004. Integrated rock magnetic and geochemical quantification of redoxomorphic iron mineral diagenesis in Late Quaternary sediments from the Equatorial Atlantic. In: Wefer, G., Mulitza, S., Ratmeyer, V. (Eds.), The South Atlantic in the Late Quaternary: reconstruction of material budgets and current systems. Springer-Verlag, Berlin/Heidelberg/New York/Tokyo, pp. 239-262). Samples with any indication of suboxic magnetite dissolution were excluded from the dataset. The parameters under study include carbonate, opal and terrigenous content, grain size distribution and clay mineral composition. Their bi- and multivariate correlations with the RPI signal were statistically investigated using standard techniques and criteria. While several of the parameters did not yield significant results, clay grain size and chlorite correlate weakly and opal, illite and kaolinite correlate moderately to the NRM/ARM signal used here as a RPI measure. The most influential single sedimentological factor is the kaolinite/illite ratio with a Pearson's coefficient of 0.51 and 99.9% significance. A three-member regression model suggests that matrix effects can make up over 50% of the observed RPI dynamics.
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Thesis (Ph.D.)--University of Washington, 2016-06
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OBJECTIVE - To assess the concurrent validity of fasting indexes of insulin sensitivity and secretion in - obese prepubertal (Tanner stage 1) children and pubertal (Tanner stages 2-5) glucose tolerance test (FSIVGTT) as a criterion measure. RESEARCH DESIGN AND METHODS - Eighteen obese children and adolescents (11 girls and 7 boys, mean age 12.2 +/- 2.4 years, mean BMI 35.4 +/- 6.2 kg/m(2), mean BMI-SDS 3.5 +/- 0.5, 7 prepubertal and I I pubertal) participated in the study. All participants underwent an insulin-modified FSIVGTT on two occasions, and 15 repeated this test a third time (mean 12.9 and 12.0 weeks apart). S-i measured by the FSIVGTT was compared with homeostasis model assessment (HOMA) of insulin resistance (HOMA-IR), quantitative insulin-sensitivity check index (QUICKI), fasting glucose-to-insulin ratio (FGIR), and fasting insulin (estimates of insulin sensitivity derived from fasting samples). The acute insulin response (AIR) measured by the FSIVGTT was compared with HOMA of percent beta-cell function (HOMA-beta%), FGIR, and fasting insulin (estimates of insulin secretion derived from fasting samples). RESULTS - There was a significant negative correlation between HOMA-IR and S-i (r = -0.89, r = -0.90, and r = -0.81, P < 0.01) and a significant positive correlation between QUICKI and S-i (r = 0.89, r = 0.90, and r = 0.81, P < 0.01) at each time point. There was a significant positive correlation between FGIR and S-i (r = 0.91, r = 0.91, and r = 0.82, P < 0.01) and a significant negative correlation between fasting insulin and S-i (r = -90, r = -0.90, and r = -0.88, P < 0.01). HOMA-beta% was not as strongly correlated with AIR (r = 0.60, r = 0.54, and r = 0.61, P < 0.05). CONCLUSIONS - HOMA-IR, QUICKI, FGIR, and fasting insulin correlate strongly with S-i assessed by the FSIVGTT in obese children and adolescents. Correlations between HOMA-β% FGIR and fasting insulin, and AIR were not as strong. Indexes derived from fasting samples are a valid tool for assessing insulin sensitivity in prepubertal and pubertal obese children.