998 resultados para 114-1
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Ammonium (NH4+) concentration profiles in piston-core sediments of the Carolina Rise and Blake Ridge generally have linear concentration profiles within the sulfate reduction zone (Borowski, 1998). Deep Sea Drilling Project (DSDP) Site 533, located on the Blake Ridge, also displayed a linear ammonium concentration profile through the sulfate reduction zone and the profile linearity continues into the upper methanogenic zone to a depth of ~200 meters below seafloor (mbsf), where the first methane gas hydrates probably occur (Jenden and Gieskes, 1983, doi:10.2973/dsdp.proc.76.114.1983; Kvenvolden and Barnard, 1983, doi:10.2973/dsdp.proc.76.106.1983). Sediments from the Ocean Drilling Program (ODP) Leg 164 deep holes (Sites 994, 995, and 997) also exhibit linear ammonium profiles above the top of the gas hydrate zone (~200 mbsf) (Paull, Matsumoto, Wallace, et al., 1996, doi:10.2973/odp.proc.ir.164.1996). We hypothesized that a possible cause of linear ammonium profiles was diffusion of ammonium from a concentrated ammonium source at depth. We further reasoned that if this ammonium were produced by microbial fermentation reactions at depth, that a comparison of the nitrogen isotopic composition of sedimentary organic nitrogen and the nitrogen with pore-water ammonium would test this hypothesis. Convergence with depth of d15N values of the nitrogen source (sedimentary organic matter) and the nitrogen product (dissolved NH4+) would strongly suggest that ammonium was produced within a particular depth zone by microbial fermentation reactions. Here, we report d15N values of pore-water ammonium from selected interstitial water (IW) samples from Site 997, sampled during ODP Leg 164.
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40Ar/39Ar analyses of tephra and clasts of volcanic rock provide age constraints for upper parts of the CRP-2A core. Single-crystal laser-fusion analyses of anorthoclase phenocrysts from three tephra-bearing layers yielded the most precise age constraints for CRP-2A. The dated tephra layers are: 1) a 2.7-m-thick interval of pumice and ash layers between 111.5 and 114.2 meters below sea floor (mbsf) (weighted mean age = 21.44 ± 0.05 Ma, +2.2); 2) a concentration of pumice near 193.4 mbsf (23.98 ± 0.13 Ma): and 3) a concentration of pumice near 280 mbsf (24,22 ± 0.03 Ma) (all ages are calibrated relative to Fish Canyon Tuff sanidine at 27.84 Ma). The 111 to 114 mbsf tephra is almost entirely non-reworked, and the 193 mbsf and 280 mbsf tephra concentrations are interpreted as being reworked and redeposited soon after eruption. All three of the tephra ages are therefore considered to be equivalent to depositional ages. The variation in precision of these three age determinations is largely a function of phenocryst size and abundance. The accuracy of these ages is equal to the accuracy of the current calibration of the 40Ar/39Ar methode (about ± 1 %). 40Ar/39Ar results from volcanic clasts provide three additional maximum age constraints for the CRP-2A core. Single-crystal laser-fusion of sanidine phenocrysts from a rhyolitic clast from 294 mbsf yielded a precise maximum depositional age of 24.98 ± 0.08 Ma, and plateau ages of groundmass concentrates from basaltic clasts near 36.02 mbsf and 125.92 mbsf yielded maximum depositional ages of 19.18 ± 0.12 Ma, and 22.56 ± 0.14 Ma, respectively. The 40Ar/39Ar data, in association with biostratigraphic, paleomagnetic, and isotopic age constraints for CRP-2A, confirm interpretation for rapid sedimentation rates in the 36 to 280 mbsf interval, particularly in the 193 to 280 mbsf interval where they support interpretations for sedimentation cycles spanning 100 k.y. intervals. In addition to the 19 to 25 Ma ages measured from thephra layers and clasts, provenance-related ages ranging from 150 to 450 Ma were determined from clasts and individual detrital or xenocrystic crystals from CRP-2A.
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Kinetic parameters for the epimerization of isoleucine in multispecific foraminiferal asemblages were used to establish the effects of burial depth and the geothermal gradient on the extent of reaction. It was observed that with a little as thirty meters of burial in a normal thermal regime there were differences between the extent of epimerization measured and that which would have been predicted for thermal equilibrium with bottom water temperatures. As would be expected, these differences are greatest when the heat flow (the geothermal gradient) and/or the sedimentation rates are highest. These effects were observed in most of the DSDP samples studied, and have been used to estimate the average heat flux since the time of sample deposition. Occasional anomalous effects were observed which could not be related to past or present heat flux. These were determined to be due to such geologic occurrences as slumping and reworking or to recent sample contamination. Other problems emerged related to bottom water temperatures including changes over geologic time which are unknown and could not be deduced. Thus, the presence of epimerization anomalies in DSDP cores as noted above limits the effectiveness of amino acid geochronology in such cores, unless these anomalies can be recognized as ab initio.
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The interaction between biogenic silica export and burial, paleoceanography, diatom species succession and mats formation was examined based on relative abundances data of Plio/Pleistocene diatoms from six cores recovered during ODP Leg 177 on a transect across the Antarctic Circumpolar Current (ACC) in the Atlantic sector of the Southern Ocean. Fragilariopsis kerguelensis, Actinocyclus ingens and species of the genus Thalassiothrix were the main contributors to the diatom assemblages. Three main steps marked the development of the silica system in the Southern Ocean: Step 1 (at ca. 2.77 Ma), establishment of increased biogenic silica burial in the Antarctic Circumpolar Current area, following the large-scale oceanic reorganization connected to the increased northern hemisphere glaciation; Step 2 (at ca. 1.93 Ma), the Antarctic Polar Front becomes the main biogenic silica sink, diatom mats are widespread, and are also found slightly to the north and south of the APF; Step 3 (at ca. 0.63 Ma), with the strong drop in abundance (and later extinction at 0.38 Ma) of A. ingens and the rise to dominance of F. kerguelensis, the system enters a glacial-interglacial mode, with diatom mats occurring during interglacials at the APF and in the Antarctic Zone, but disappearing north of it.
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Ne, Ar, Kr, Xe, and K2O were measured in representative samples of holocrystalline basalt from DSDP Hole 504B. No hiatus in inert gas abundance is recognized at the base of the "oxic" alteration zone and the extent rather than the nature of alteration appears to determine these abundances. When the inert gas abundances are separately plotted against K2O, two distinct trends of loss emerge, one for alteration involving K-gain, the other for K-loss. Apparent whole-rock K-Ar ages are anomalous in the upper 50 m of basement, and below 300 m sub-basement. In the intervening zone of basement, celadonization adds sufficient potassium and eliminates enough "primary" 40Ar early in the history of the basalts for "excess" 40Ar to become subordinate to radiogenic 40Ar in basalts showing potassium enrichment greater than 0.2%. Stratigraphically correct K-Ar ages are obtained, therefore, from K-enriched basalts of the oxic alteration zone.
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Based on the X-ray fluorescence spectrum analysis of 15 rare earth elements in 6 ferromanganese nodu1es and 5 ferro mangane se crusts from the South China Sea, their abundances, distribution patterns, sources and relationships with associated elements are discussed in detail in this paper. The results show that: 1) The average abundance of rare earth elements in ferromanganese nodu1es and crusts is 1. 625 g/kg and 2. 167 g/kg respectively, which is 1-2 tim es , 5-6 times and 15-20 times higher than that in the Pacific, in the sediments of the North Pacific and the South China Sea, respectively; 2) The distribution patterns of rare earth elements standardized by the globular aerolite in ferro mangane se nodules and crusts are basically similar, that is, Ce is positively abnormal and Eu is in deficit slightly; 3) The relationships between rare earth elements and associated elements, sediments and rocks show that the source of rare earth elements in ferromanganese nodules and crusts have mainly come from slow deposition caused by weathering and leaching of medium acidic rock of the South China Sea.
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Introduction - Nutritional therapy (NT) is a bioscience-based branch of complementary and alternative medicine (CAM) with National Occupational Standards (NOS) and accredited training courses which include compulsory clinical training. Approximately 900 practitioners are registered with the voluntary regulator, the Complementary and Natural Healthcare Council (CNHC), but the number of unregulated practitioners is unknown. Cancer is a leading cause of death worldwide; nutrition and lifestyle factors may affect recurrence and survival rates. Many cancer patients and survivors seek individualised advice on diet and use of supplements and appropriately skilled nutritional therapy practitioners (NTP) may be well-placed to safely provide this advice. Little is known of NTPs’ perspectives on working with people affected by cancer; this study seeks to explore their views on training, use of evidence and other resources, to support the development of safe evidence-based practice in this important clinical area. Methods – An on-line anonymised questionnaire collected data from participants recruited from all UK registered NTPs. Recruitment was facilitated by the British Association for Applied Nutrition and Nutritional Therapy (BANT). Quantitative data on practitioner characteristics, years in practice, other therapies practiced and work with cancer clients were collected. Qualitative data on types of evidence used, barriers to practice and perceived training and support needs when working with clients with cancer, were collected and analysed. SPSS was used to produce descriptive statistics. Preliminary Results – 274/888 (31%) of registered NTPs participated. 61% respondents had accredited NT qualifications of which 46% were at degree or post-graduate level. 73% (202) participants indicated they also had other higher education qualifications, including 153 (56%) at degree or above. When asked to describe their position on cancer work, 17% respondents (40/238) indicated no interest, and 35% (84/238) respondents already work with cancer clients (cancer practitioners - CP). A further 48% (114/238) respondents expressed interest in starting cancer work, and typically requested specialist training and practice guidelines to support this area of clinical practice. Cancer practitioners (CP) rated searches of peer-reviewed literature as most useful for information to support practice, whereas commercial product information was rated least useful. CPs requested engagement with mainstream medicine, more access to research evidence and professional recognition to facilitate and support work with cancer clients. A need for professional networking, mentorship and/or supervision was noted by CP and non-CP respondents, which is of interest since 81% all participants worked as sole practitioners exclusively or as part of their practice, <1% worked within the NHS. Discussion & Conclusions – This is the first detailed documentation of NTP perspectives on cancer work. A number of areas have been identified for further detailed evidence to be collected using focus groups and interviews, including detailed training needs, communication with mainstream cancer professionals, access to research evidence, and professional recognition. This work will inform and support the development of professional practice guidelines for NT and inform the development of specialist training and other resources.
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As noted in Part 1 of this report, the objective of the investigation was to apply principles of first-arrival seismic refraction to the problem of more quickly determining in-place dry density in highway materials. Part 2 of the report, contained herein, presents the results of both additional laboratory development of test techniques, plus extensive field test data.
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Este estudo tem como finalidade compreender o processo de constituição de uma parceria educativa envolvendo escolas do 1.º Ciclo do Ensino Básico e outras instituições da comunidade para a promoção da educação intercultural e analisar a influência do trabalho desenvolvido por essa parceria nas práticas, atitudes, competências e conhecimentos de todos os participantes. Situa-se, por um lado, num entendimento de educação intercultural enquanto abordagem educativa fundamental para todos os alunos, assente na valorização da diversidade e na promoção de atitudes e competências de relacionamento interpessoal (como o respeito e a solidariedade), tendo em vista a formação de cidadãos responsáveis e participativos na construção de sociedades mais justas e coesas. Por outro, justifica o potencial das parcerias educativas para o desenvolvimento pessoal, profissional e institucional dos parceiros, assim como para o desenvolvimento da competência intercultural de todos os participantes (parceiros, alunos e comunidade envolvente). O desenho investigativo delineado, de natureza predominantemente qualitativa, encontra-se na interseção de três métodos investigativos: estudo de caso, estudo etnográfico e investigação-ação. Num primeiro momento (ano letivo 2008/2009) efetuou-se um estudo exploratório que visou conhecer as práticas de educação intercultural e de trabalho em parceria de professores a lecionar em escolas do 1.º CEB do concelho de Aveiro. O objetivo deste estudo era reunir sugestões de atividades e de instituições a contactar para a constituição de um grupo de parceiros com vista ao desenvolvimento posterior de um projeto sobre educação intercultural. Os dados recolhidos por meio da aplicação de um inquérito por questionário a 228 professores do 1º CEB do distrito de Aveiro (dos quais 114 foram respondidos) permitiram concluir que as práticas educativas a este nível, e no contexto em causa, são ainda escassas ou pouco divulgadas. Passou-se, então, à constituição de um grupo de parceiros educativos que contou com um total de 13 elementos: a investigadora, enquanto parceira representante da Universidade de Aveiro, seis professoras do 1.º CEB, duas professoras de Música das Atividades de Enriquecimento Curricular, um representante de uma associação de imigrantes, um representante de uma associação cultural, um representante de uma CERCI e um representante da Câmara e Biblioteca Municipal. Ao longo do ano escolar 2010/2011, o grupo de parceiros desenvolveu colaborativamente um projeto de intervenção sobre educação intercultural para alunos do 1.º CEB. Este projeto proporcionou-lhes momentos de formação sobre educação intercultural e jogos colaborativos e permitiu-lhes partilhar as suas dúvidas e experiências relativas à temática em causa, propor estratégias e metodologias e disponibilizar recursos para a conceção e implementação das atividades. Os dados foram recolhidos em diferentes momentos: antes de se dar início ao projeto de intervenção, efetuou-se uma entrevista inicial a cada um dos parceiros; durante o decorrer do projeto realizou-se um focus group e registaram-se em formato áudio todas as sessões de trabalho entre os parceiros; após a conclusão do projeto de intervenção, teve lugar uma nova entrevista individual a cada um deles. Estes dados foram transcritos e analisados de acordo com a técnica de análise de conteúdo. Para além disso, todos os documentos elaborados pela investigadora durante a gestão da parceria, os portfólios das professoras participantes e os registos fotográficos das atividades implementadas constituíram-se como dados secundários. Os resultados mostraram que a participação neste projeto: i) conduziu a que ocorresse uma alteração das representações dos parceiros sobre interculturalidade e educação intercultural; ii) permitiu a todos os participantes (parceiros, alunos e comunidade) desenvolverem a sua competência intercultural; iii) proporcionou situações de trabalho colaborativo que contribuíram para o desenvolvimento pessoal, profissional e institucional de todos os parceiros; iv) motivou os parceiros a darem continuidade ao trabalho aqui desenvolvido. Este estudo permitiu, ainda, refletir sobre a importância da formação de formadores em educação intercultural e da necessidade de sensibilização para o desenvolvimento de trabalho colaborativo entre escola, comunidade e investigadores académicos.
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Digitalizacja i deponowanie archiwalnych zeszytów RPEiS sfinansowane przez MNiSW w ramach realizacji umowy nr 541/P-DUN/2016
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This study aimed at evaluating the functional activation and activating receptors expression on resting, short- and long-term NK and NK-like T cells from blood of ovarian neoplasia patients. Blood from patients with adnexal benign alterations (n = 10) and ovarian cancer (grade I-IV n = 14) were collected after signed consent. Effector cells activation was evaluated by the expression of the CD107a molecule. Short-term culture was conducted overnight with IL-2 and long-term culture for 21 days, by a method designed to expand CD56(+) lymphocytes. Short-term culture significantly increased NK cells activation compared to resting NK cells (p<0.05), however, the long-term procedure supported an even higher increase (p<0.001). Resting NK-like T cells showed poor activation, which was not altered by the culture procedures. The long-term culture effectively increased the expression of the activating receptors on NK and NK-like T cells, either by increasing the number of cells expressing a given receptor and/or by up-regulating their expression intensity. As a conclusion, the long-term culture system employed, resulted in a high number of functional NK cells. The culture system was particularly efficient on the up-regulation of NKp30 and DNAM-1 receptors on NK cells.
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Human bocavirus 1 (HBoV1) is associated with respiratory infections worldwide, mainly in children. Similar to other parvoviruses, it is believed that HBoV1 can persist for long periods of time in humans, probably through maintaining concatemers of the virus single-stranded DNA genome in the nuclei of infected cells. Recently, HBoV-1 was detected in high rates in adenoid and palatine tonsils samples from patients with chronic adenotonsillar diseases, but nothing is known about the virus replication levels in those tissues. A 3-year prospective hospital-based study was conducted to detect and quantify HBoV1 DNA and mRNAs in samples of the adenoids (AD), palatine tonsils (PT), nasopharyngeal secretions (NPS), and peripheral blood (PB) from patients undergoing tonsillectomy for tonsillar hypertrophy or recurrent tonsillitis. HBoV1 was detected in 25.3% of the AD samples, while the rates of detection in the PT, NPS, and PB samples were 7.2%, 10.5%, and 1.7%, respectively. The viral loads were higher in AD samples, and 27.3% of the patients with HBoV had mRNA detectable in this tissue. High viral loads and detectable mRNA in the AD were associated with HBoV1 detection in the other sample sites. The adenoids are an important site of HBoV1 replication and persistence in children with tonsillar hypertrophy. The adenoids contain high HBoV1 loads and are frequently positive for HBoV mRNA, and this is associated with the detection of HBoV1 in secretions.
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This study aimed to identify novel biomarkers for thyroid carcinoma diagnosis and prognosis. We have constructed a human single-chain variable fragment (scFv) antibody library that was selected against tumour thyroid cells using the BRASIL method (biopanning and rapid analysis of selective interactive ligands) and phage display technology. One highly reactive clone, scFv-C1, with specific binding to papillary thyroid tumour proteins was confirmed by ELISA, which was further tested against a tissue microarray that comprised of 229 thyroid tissues, including: 110 carcinomas (38 papillary thyroid carcinomas (PTCs), 42 follicular carcinomas, 30 follicular variants of PTC), 18 normal thyroid tissues, 49 nodular goitres (NG) and 52 follicular adenomas. The scFv-C1 was able to distinguish carcinomas from benign lesions (P=0.0001) and reacted preferentially against T1 and T2 tumour stages (P=0.0108). We have further identified an OTU domain-containing protein 1, DUBA-7 deubiquitinating enzyme as the scFv-binding antigen using two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. The strategy of screening and identifying a cell-surface-binding antibody against thyroid tissues was highly effective and resulted in a useful biomarker that recognises malignancy among thyroid nodules and may help identify lower-risk cases that can benefit from less-aggressive management.