182 research outputs found
Jahrringe von Schwarzkiefer und Eiche unterschiedlicher Standorte als Proxy fĂŒr Wasserstandsschwankungen des Neusiedler Sees
Historische Aufzeichnungen bis ins Jahr 1074 zurĂŒck belegen, dass der Wasserstand des Neusiedler Sees starken Schwankungen unterliegt, die von Ăberflutungen bis hin zur vollkommenen Austrocknung reichen können. Wie die VerĂ€nderungen des Seespiegels ist auch der jĂ€hrliche Zuwachs der Schwarzkiefer Pinus nigra sowie der Traubeneiche Quercus petraea bzw. der Stieleiche Quercus robur vom Niederschlag bzw. der klimatischen Wasserbilanz abhĂ€ngig. Daher sollten sowohl der Seespiegel als auch die Jahrringbreiten von BĂ€umen im Einzugsgebiet eine Ă€hnliche zeitliche Entwicklung aufweisen. Die vorliegende Diplomarbeit untersucht, ob die Jahrringe der o. g. Baumarten als Proxy fĂŒr die Wasserstandsschwankungen des Neusiedler Sees geeignet sind und wie unterschiedliche Standortbedingungen dieses Potenzial beeinflussen.
Die Untersuchung beinhaltet die Beschreibung der KlimasensitivitĂ€t von 127 BĂ€umen (60 Eichen und 67 Schwarzkiefern) an acht unterschiedlichen Standorten im Leithagebirge durch die Analyse von Klima-Wachstums-Beziehungen (Response-Function-Analyse von Jahrring-, FrĂŒhholz- und SpĂ€tholzbreite sowie SpĂ€tholzanteil einerseits und sechs verschiedenen Klimaelementen monatlicher Auflösung andererseits), die landschaftsökologische Aufnahme der Standorte und der dort vorkommenden Böden sowie die statistische Beschreibung der Beziehungen zwischen den Jahrringparametern und zwei verschiedenen Varianten von Seespiegelmittelwerten mittels linearer Regressionen.
Die Ergebnisse zeigen, dass die Schwarzkiefer zwar eine höhere KlimasensitivitĂ€t aufweist, die Eiche aber den Seespiegel besser abbildet. Mit einem linearen Modell, das Jahrringparameter beider Baumarten einbezieht, ist unter UmstĂ€nden die Rekonstruktion der Wasserstandsschwankungen des Neusiedler Sees ĂŒber den Zeitraum instrumenteller Aufzeichnungen hinaus möglich.Historical records back to 1074 AD show that the water level of Lake Neusiedl has been subject to great fluctuations â not only floods but also periods where the basin was completely dry occurred in the past. These fluctuations as well as the annual increment of black pine Pinus nigra and sessile oak Quercus petraea or English oak Quercus robur are dependent on precipitation resp. climatic water balance. Therefore, lake level and tree ring widths should show similar chronological developments. This diploma thesis investigates the applicability of the mentioned speciesâ tree rings as a proxy for the lake level fluctuations and how different site conditions influence this potential.
The investigations include the description of 127 treesâ (67 black pines and 60 oaks) climate sensitivity at eight different sites in the Leitha Mountains by examination of climate-growth-relationships (response-function-analysis of tree ring width, earlywood width, latewood width and latewood percentage on one hand and six different climate elements at monthly resolution on the other hand), the characterisation of the sites and their soil types as well as the statistical description of the relationships between tree ring parameters and two different lake level mean values by linear regression.
The results display that black pine shows higher climate sensitivity but oakâs reproduction of the lake level is better. A linear model consisting of both speciesâ chronologies can possibly be used to reconstruct Lake Neusiedlâs fluctuations beyond the period of instrumental records
VISION - Vienna survey in Orion. III. Young stellar objects in Orion A
38 pages, 25 figures, Accepted for publication by A&A. Reproduced with permission from Astronomy & Astrophysics. © 2018 ESOWe extend and refine the existing young stellar object (YSO) catalogs for the Orion A molecular cloud, the closest massive star-forming region to Earth. This updated catalog is driven by the large spatial coverage (18.3 deg^2, ~950 pc^2), seeing limited resolution (~0.7''), and sensitivity (Ks<19 mag) of the ESO-VISTA near-infrared survey of the Orion A cloud (VISION). Combined with archival mid- to far-infrared data, the VISTA data allow for a refined and more robust source selection. We estimate that among previously known protostars and pre-main-sequence stars with disks, source contamination levels (false positives) are at least âŒ7% and âŒ2.5%, respectively, mostly due to background galaxies and nebulosities. We identify 274 new YSO candidates using VISTA/Spitzer based selections within previously analyzed regions, and VISTA/WISE based selections to add sources in the surroundings, beyond previously analyzed regions. The WISE selection method recovers about 59% of the known YSOs in Orion A's low-mass star-forming part L1641, which shows what can be achieved by the all-sky WISE survey in combination with deep near-infrared data in regions without the influence of massive stars. The new catalog contains 2978 YSOs, which were classified based on the de-reddened mid-infrared spectral index into 188 protostars, 184 flat-spectrum sources, and 2606 pre-main-sequence stars with circumstellar disks. We find a statistically significant difference in the spatial distribution of the three evolutionary classes with respect to regions of high dust column-density, confirming that flat-spectrum sources are at a younger evolutionary phase compared to Class IIs, and are not a sub-sample seen at particular viewing angles.Peer reviewedFinal Accepted Versio
âWhat smell?â Temporarily loading visual attention induces a prolonged loss of olfactory awareness
The human sense of smell is highly sensitive, often conveying important biological signals. Yet, anecdotal evidence suggests that we commonly fail to notice supra-threshold environmental olfactory stimuli. The determinants of olfactory awareness are, as yet, unknown. Here, we adapted the âinattentional blindnessâ paradigm, to test whether olfactory awareness is dependent on attention. Across three experiments, participants performed a visual search task with either a high or low perceptual load (a well-established attentional manipulation) while exposed to an ambient coffee aroma. Consistent with our hypothesis, task load modulated olfactory awareness: 42.5% fewer participants in the high (vs. low) load condition reported noticing the coffee aroma. Our final experiment demonstrates that, due to unique characteristics of olfactory habituation, the consequences of inattentional anosmia can persist even once attention becomes available. These findings establish the phenomenon of inattentional anosmia, and have applied implications for predicting when people may miss potentially important olfactory information
3D shape of Orion A from Gaia DR2
Reproduced with permission from Astronomy & Astrophysics. © 2018 ESO.We use the Gaia DR2 distances of about 700 mid-infrared selected young stellar objects in the benchmark giant molecular cloud Orion A to infer its 3D shape and orientation. We find that Orion A is not the fairly straight filamentary cloud that we see in (2D) projection, but instead a cometary-like cloud oriented toward the Galactic plane, with two distinct components: a denser and enhanced star-forming (bent) Head, and a lower density and star-formation quieter ~75 pc long Tail. The true extent of Orion A is not the projected ~40 pc but ~90 pc, making it by far the largest molecular cloud in the local neighborhood. Its aspect ratio (~30:1) and high column-density fraction (~45%) make it similar to large-scale Milky Way filaments ("bones"), despite its distance to the galactic mid-plane being an order of magnitude larger than typically found for these structures.Peer reviewedFinal Accepted Versio
Incidence and outcome of intracranial malignant germ cell tumours diagnosed in western Denmark in the last decade
Safety of selenium-enriched biomass of Yarrowia lipolytica as a novel food pursuant to Regulation (EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on selenium-enriched biomass of Yarrowia lipolytica as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is the dried and heat-killed selenium-enriched biomass of Y. lipolytica. This yeast species is widespread in nature, can be found in the environment and in foods, and was attributed the qualified presumption of safety (QPS) status for production purposes in 2018, including food and feed products based on biomass of the yeast. The production process, fermentation in the presence of sodium selenite, includes a heat-killing step of the yeast, resulting in the absence of viable Y. lipolytica in the NF. The maximum total selenium content in the NF is 200 mu g Se/g, mainly present as organic selenium compounds. The applicant proposed to use the NF as a food supplement. The target population proposed by the applicant is the general population from 3 years of age onwards, with maximum proposed use levels of 0.2 g/day for children from 3 to 9 years of age and 1 g/day thereafter. The Panel considers that the yeast biomass is not of safety concern at the proposed use levels. The Panel also considers that the selenium provided by the NF is as safe as selenium from other dietary sources. However, the Panel notes that, at the use levels proposed by the applicant, the intake of the NF could, in combination with a background diet high in selenium, lead to total selenium intakes exceeding the UL for selenium in all target population groups, except for children from 7 to 9 years. Furthermore, the Panel considers that newly emerging data warrant a reassessment of the UL for selenium. (C) 2020 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.Non peer reviewe
Novel foods in the European Union: Scientific requirements and challenges of the risk assessment process by the European Food Safety Authority
The European Food Safety Authority (EFSA) has been involved in the risk assessment of novel foods since 2003. The implementation of the current novel food regulation in 2018 rendered EFSA the sole entity of the European Union responsible for such safety evaluations. The risk assessment is based on the data submitted by applicants in line with the scientific requirements described in the respective EFSA guidance document. The present work aims to elaborate on the rationale behind the scientific questions raised during the risk assessment of novel foods, with a focus on complex mixtures and whole foods. Novel foods received by EFSA in 2003â2019 were screened and clustered by nature and complexity. The requests for additional or supplementary information raised by EFSA during all risk assessments were analyzed for identifying reoccurring issues. In brief, it is shown that applications concern mainly novel foods derived from plants, microorganisms, fungi, algae, and animals. A plethora of requests relates to the production process, the compositional characterization of the novel food, and the evaluation of the product's toxicological profile. Recurring issues related to specific novel food categories were noted. The heterogeneous nature and the variable complexity of novel foods emphasize the challenge to tailor aspects of the evaluation approach to the characteristics of each individual product. Importantly, the scientific requirements for novel food applications set by EFSA are interrelated, and only a rigorous and cross-cutting approach adopted by the applicants when preparing the respective application dossiers can lead to scientifically sound dossiers. This is the first time that an in-depth analysis of the experience gained by EFSA in the risk assessment of novel foods and of the reasoning behind the most frequent scientific requests by EFSA to applicants is made
Novel foods in the European Union: Scientific requirements and challenges of the risk assessment process by the European Food Safety Authority
The European Food Safety Authority (EFSA) has been involved in the risk assessment of novel foods since 2003. The implementation of the current novel food regulation in 2018 rendered EFSA the sole entity of the European Union responsible for such safety evaluations. The risk assessment is based on the data submitted by applicants in line with the scientific requirements described in the respective EFSA guidance document. The present work aims to elaborate on the rationale behind the scientific questions raised during the risk assessment of novel foods, with a focus on complex mixtures and whole foods. Novel foods received by EFSA in 2003-2019 were screened and clustered by nature and complexity. The requests for additional or supplementary information raised by EFSA during all risk assessments were analyzed for identifying reoccurring issues. In brief, it is shown that applications concern mainly novel foods derived from plants, microorganisms, fungi, algae, and animals. A plethora of requests relates to the production process, the compositional characterization of the novel food, and the evaluation of the product's toxicological profile. Recurring issues related to specific novel food categories were noted. The heterogeneous nature and the variable complexity of novel foods emphasize the challenge to tailor aspects of the evaluation approach to the characteristics of each individual product. Importantly, the scientific requirements for novel food applications set by EFSA are interrelated, and only a rigorous and cross-cutting approach adopted by the applicants when preparing the respective application dossiers can lead to scientifically sound dossiers. This is the first time that an in-depth analysis of the experience gained by EFSA in the risk assessment of novel foods and of the reasoning behind the most frequent scientific requests by EFSA to applicants is made
Statement on the safety of synthetic L-ergothioneine as a novel food - supplementary dietary exposure and safety assessment for infants and young children, pregnant and breastfeeding women
Following a request from the European Commission, the EFSA Panelon Dietetic Products, Nutrition and Allergies (NDA) was asked to provide a supplementary dietary exposure and safety assessment of synthetic l-ergothioneine for those groups of the population which had been excluded by the applicant in the original application, i.e. infants and young children (i.e. toddlers), pregnant and breastfeeding women. Thus, intake estimates were calculated for these population groups and the following maximum anticipated daily intakes of l-ergothioneine from the NF, in addition to the background diet, were calculated: 2.82 mg/kg body weight (bw) per day for infants, 3.39 mg/kg bw per day for toddlers and 1.31 mg/kg bw per day for adults including pregnant and breastfeeding women. The Panelconsiders that based on the overall toxicological data the no-observed-adverse-effect level (NOAEL) of 800 mg/kg bw per day as established in the original assessment also pertains to pregnant and breastfeeding women as well as to young children (i.e. toddlers) and infants. The corresponding margins of exposure (i.e. the ratio between the NOAEL and the maximum anticipated daily intakes) are 284 for infants, 236 for young children and 610 for pregnant and breastfeeding women. These margins of exposure are considered sufficient. The Panelconcludes that the novel food, synthetic l-ergothioneine, is safe under the proposed uses and use levels for infants, young children (i.e. toddlers) and pregnant and breastfeeding women
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