191 research outputs found

    Diatom biostratigraphic correlation of Deep Sea Drilling Project Sites 270, 272, Ross Sea, Antarctica

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    Drilling Sites 270, 272, and 271 of the Deep Sea Drilling Project, (DSDP) were intended to sample a thick continuous sequence of sediments in the Ross Sea. This objective was not achieved due to the fact that the requisite depths were not reached. Diatom assemblages from DSDP Sites 270 and 272 are used to determine the temporal relationship between these holes. Diatoms reported here from Site 270, represent the first pre-Pleistocene diatoms recovered at this locality. Ages and diatom zonations of earlier studies of these sites are confirmed, although some revisions are made. A maximum age for the lower most portion of hole 272 is determined at 17.5 m.y., 1,7 m.y. younger than what had been previously accepted. A minimum age of 20.7 m.y. for the top of hole 270 is proposed here, which agrees with the ages derived from the foraminiferal studies of Leckie and Webb (1983). A 3.5 m.y. gap separates the sections cored in Sites 270 and 272, as indicated by the Early - Middle Neogene diatom zonations of Weaver and Gombos (1981) and Harwood (in press) used in this study. This unsampled interval represents a significant data gap in the Early Neogene sedimentary record of this region.No embarg

    Metabolic imprinting, programming and epigenetics - a review of present priorities and future opportunities

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    Metabolic programming and metabolic imprinting describe early life events, which impact upon on later physiological outcomes. Despite the increasing numbers of papers and studies, the distinction between metabolic programming and metabolic imprinting remains confusing. The former can be defined as a dynamic process whose effects are dependent upon a critical window(s) while the latter can be more strictly associated with imprinting at the genomic level. The clinical end points associated with these phenomena can sometimes be mechanistically explicable in terms of gene expression mediated by epigenetics. The predictivity of outcomes depends on determining if there is causality or association in the context of both early dietary exposure and future health parameters. The use of biomarkers is a key aspect of determining the predictability of later outcome, and the strengths of particular types of biomarkers need to be determined. It has become clear that several important health endpoints are impacted upon by metabolic programming/imprinting. These include the link between perinatal nutrition, nutritional epigenetics and programming at an early developmental stage and its link to a range of future health risks such as CVD and diabetes. In some cases, the evidence base remains patchy and associative, while in others, a more direct causality between early nutrition and later health is clear. In addition, it is also essential to acknowledge the communication to consumers, industry, health care providers, policy-making bodies as well as to the scientific community. In this way, both programming and, eventually, reprogramming can become effective tools to improve health through dietary intervention at specific developmental points

    Initial investigations into the MOS interface of freestanding 3C-SiC layers for device applications

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    This letter reports on initial investigation results on the material quality and device suitability of a homo-epitaxial 3C-SiC growth process. Atomic force microscopy surface investigations revealed root-mean square surface roughness levels of 163.21 nm, which was shown to be caused by pits (35 ÎŒm width and 450 nm depth) with a density of 1.09 × 105 cm−2 which had formed during material growth. On wider scan areas, the formation of these were seen to be caused by step bunching, revealing the need for further epitaxial process improvement. X-ray diffraction showed good average crystalline qualities with a full width of half-maximum of 160 arcseconds for the 3C-SiC (002) being lower than for the 3C-on-Si material (210 arcseconds). The analysis of C–V curves then revealed similar interface-trapped charge levels for freestanding 3C-SiC, 3C-SiC on Si and 4H-SiC, with forming gas post-deposition annealed freestanding 3C-SiC devices showing DIT levels of 3.3 × 1011 cm−2 eV−1 at EC−ET = 0.2 eV. The homo-epitaxially grown 3C-SiC material's suitability for MOS applications could also be confirmed by leakage current measurements

    THE RELATIONSHIP BETWEEN RISK MANAGEMENT STRATEGIES AND INVESTMENT BEHAVIOR OF GENERATION Z RETAIL INVESTORS IN STA. MESA, MANILA

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    Risk Management Strategies and Investment Behaviors are considered important factors in the investing activities of the retail investors. This study seeks to determine the relationship between Risk Management Strategies and Investment Behavior of Generation Z retail investors. The study is a correlational research and purposive sampling was used to select the respondents for this study. Cochran’s formula was utilized to determine the total sample size or total number of respondents. Spearman’s Rank-Order Correlation was employed to assess the significant relationship of Risk Management Strategies and Investment Behaviors. Based on the results, it showed that risk management strategies have a significant relationship with one or more of the investment behaviors. Risk avoidance has a significant relationship with confirmation bias. Risk reduction has a significant relationship with all of the investment behaviors such as overconfidence, loss-aversion, recency bias, and confirmation bias. Risk transfer shows a significant relationship with only loss-aversion and confirmation bias. And lastly, risk acceptance also has a significant relationship with all of the investment behaviors. This study recommends exploring other types of behavioral biases under cognitive bias and emotional bias to determine their correlation with risk management strategies. Also, broadening the sample size, demographic scope, and geographic scope of the study can improve the generalizability of the study and provide a more comprehensive understanding of the relationship between investment behavior and risk management strategies. The researchers also recommend to utilize interviews and focus group discussions to gain an in-depth understanding of the underlying values and attitudes concerning investment behavior

    Latent class analysis reveals clinically relevant atopy phenotypes in 2 birth cohorts

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    Background: Phenotypes of childhood-onset asthma are characterized by distinct trajectories and functional features. For atopy, definition of phenotypes during childhood is less clear. Objective: We sought to define phenotypes of atopic sensitization over the first 6 years of life using a latent class analysis (LCA) integrating 3 dimensions of atopy: allergen specificity, time course, and levels of specific IgE (sIgE). Methods: Phenotypes were defined by means of LCA in 680 children of the Multizentrische Allergiestudie (MAS) and 766 children of the Protection against allergy: Study in Rural Environments (PASTURE) birth cohorts and compared with classical nondisjunctive definitions of seasonal, perennial, and food sensitization with respect to atopic diseases and lung function. Cytokine levels were measured in the PASTURE cohort. Results: The LCA classified predominantly by type and multiplicity of sensitization (food vs inhalant), allergen combinations, and sIgE levels. Latent classes were related to atopic disease manifestations with higher sensitivity and specificity than the classical definitions. LCA detected consistently in both cohorts a distinct group of children with severe atopy characterized by high seasonal sIgE levels and a strong propensity for asthma; hay fever; eczema; and impaired lung function, also in children without an established asthma diagnosis. Severe atopy was associated with an increased IL-5/IFN-gamma ratio. A path analysis among sensitized children revealed that among all features of severe atopy, only excessive sIgE production early in life affected asthma risk. Conclusions: LCA revealed a set of benign, symptomatic, and severe atopy phenotypes. The severe phenotype emerged as a latent condition with signs of a dysbalanced immune response. It determined high asthma risk through excessive sIgE production and directly affected impaired lung function.Peer reviewe

    The international EAACI/GA(2)LEN/EuroGuiDerm/APAAACI guideline for the definition, classification, diagnosis, and management of urticaria

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    Publisher Copyright: © 2021 GAÂČLEN. Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.This update and revision of the international guideline for urticaria was developed following the methods recommended by Cochrane and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group. It is a joint initiative of the Dermatology Section of the European Academy of Allergology and Clinical Immunology (EAACI), the Global Allergy and Asthma European Network (GA(2)LEN) and its Urticaria and Angioedema Centers of Reference and Excellence (UCAREs and ACAREs), the European Dermatology Forum (EDF; EuroGuiDerm), and the Asia Pacific Association of Allergy, Asthma and Clinical Immunology with the participation of 64 delegates of 50 national and international societies and from 31 countries. The consensus conference was held on 3 December 2020. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS). Urticaria is a frequent, mast cell-driven disease that presents with wheals, angioedema, or both. The lifetime prevalence for acute urticaria is approximately 20%. Chronic spontaneous or inducible urticaria is disabling, impairs quality of life, and affects performance at work and school. This updated version of the international guideline for urticaria covers the definition and classification of urticaria and outlines expert-guided and evidence-based diagnostic and therapeutic approaches for the different subtypes of urticaria.Peer reviewe

    The international EAACI/GAÂČLEN/EuroGuiDerm/APAAACI guideline for the definition, classification, diagnosis, and management of urticaria

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    This update and revision of the international guideline for urticaria was developed following the methods recommended by Cochrane and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group. It is a joint initiative of the Dermatology Section of the European Academy of Allergology and Clinical Immunology (EAACI), the Global Allergy and Asthma European Network (GA(2)LEN) and its Urticaria and Angioedema Centers of Reference and Excellence (UCAREs and ACAREs), the European Dermatology Forum (EDF; EuroGuiDerm), and the Asia Pacific Association of Allergy, Asthma and Clinical Immunology with the participation of 64 delegates of 50 national and international societies and from 31 countries. The consensus conference was held on 3 December 2020. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS). Urticaria is a frequent, mast cell-driven disease that presents with wheals, angioedema, or both. The lifetime prevalence for acute urticaria is approximately 20%. Chronic spontaneous or inducible urticaria is disabling, impairs quality of life, and affects performance at work and school. This updated version of the international guideline for urticaria covers the definition and classification of urticaria and outlines expert-guided and evidence-based diagnostic and therapeutic approaches for the different subtypes of urticaria
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