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Wohlfahrt G.,University of Innsbruck | Tasser E.,European Academy of Bolzano
International Journal of Biometeorology | Year: 2015

We present a mobile device for the quantification of the small-scale (a few square meters) spatial variability in the surface energy balance components and several auxiliary variables of short-statured (<1 m) canopies. The key element of the mobile device is a handheld four-component net radiometer for the quantification of net radiation, albedo and infrared surface temperature, which is complemented with measurements of air temperature, wind speed, soil temperature and soil water content. Data are acquired by a battery-powered data logger, which is mounted on a backpack together with the auxiliary sensors. The proposed device was developed to bridge between the spatial scales of satellite/airborne remote sensing and fixed, stationary tower-based measurements with an emphasis on micrometeorological, catchment hydrological and landscape–ecological research questions. The potential of the new device is demonstrated through four selected case studies, which cover the issues of net radiation heterogeneity within the footprint of eddy covariance flux measurements due to (1) land use and (2) slope and aspect of the underlying surface, (3) controls on landscape-scale variability in soil temperature and albedo and (4) the estimation of evapotranspiration based exclusively on measurements with the mobile device. © 2014, The Author(s).


Hortnagl L.,University of Innsbruck | Hortnagl L.,ETH Zurich | Wohlfahrt G.,University of Innsbruck | Wohlfahrt G.,European Academy of Bolzano
Biogeosciences | Year: 2014

The methane (CH4) and nitrous oxide (N2O) exchange of a temperate mountain grassland near Neustift, Austria, was measured during 2010-2012 over a time period of 22 months using the eddy covariance method. Exchange rates of both compounds at the site were low, with 97% of all half-hourly CH4 and N2O fluxes ranging between ±200 and ±50 ngm-2 s-1, respectively. The meadow acted as a sink for both compounds during certain time periods, but was a clear source of CH4 and N2O on an annual timescale. Therefore, both gases contributed to an increase of the global warming potential (GWP), effectively reducing the sink strength in terms of CO2 equivalents of the investigated grassland site. In 2011, our best guess estimate showed a net greenhouse gas (GHG) sink of -32 g CO2 equ. m-2 yr-1 for the meadow, whereby 55% of the CO2 sink strength of -71 g CO2 m-2 yr-1 was offset by CH4 (N2O) emissions of 7 (32) g CO2 equ. m-2 yr-1. When all data were pooled, the ancillary parameters explained 27 (42)% of observed CH4 (N2O) flux variability, and up to 62 (76)% on shorter timescales in-between management dates. In the case of N2O fluxes, we found the highest emissions at intermediate soil water contents and at soil temperatures close to 0 or above 14°C. In comparison to CO2, H2O and energy fluxes, the interpretation of CH4 and N2O exchange was challenging due to footprint heterogeneity regarding their sources and sinks, uncertainties regarding post-processing and quality control. Our results emphasize that CH4 and N2O fluxes over supposedly well-aerated and moderately fertilized soils cannot be neglected when evaluating the GHG impact of temperate managed grasslands. © Author(s) 2014.


Wohlfahrt G.,University of Innsbruck | Wohlfahrt G.,European Academy of Bolzano | Gu L.,Oak Ridge National Laboratory
Plant, Cell and Environment | Year: 2015

Gross photosynthesis is a key term in plant biology and carbon cycle science, however has been used with different meanings by different communities We review the history of this term and associated concepts to clarify the terminology and make recommendations about a consistent use of terms in accordance with photosynthetic theory. We show that a widely used eddy covariance CO2 flux partitioning approach yields estimates which are quantitatively closer to the definition of true photosynthesis despite aiming at estimating apparent photosynthesis. © 2015 John Wiley & Sons Ltd.


PubMed | European Academy of Bolzano and University of Innsbruck
Type: | Journal: Agricultural and forest meteorology | Year: 2017

In complex, sloping terrain, horizontal measurements of net radiation are not reflective of the radiative energy available for the conductive and convective heat exchange of the underlying surface. Using data from a grassland site on a mountain slope characterised by spatial heterogeneity in inclination and aspect, we tested the hypothesis that a correction of the horizontal net radiation measurements which accounts for the individual footprint contributions of the various surfaces to the measured sensible and latent heat eddy covariance fluxes will yield more realistic slope-parallel net radiation estimates compared to a correction based on the average inclination and aspect of the footprint. Our main result is that both approaches led to clear, but very similar improvements in the phase between available energy and the sum of the latent and sensible heat fluxes. As a consequence the variance in the sum of latent and sensible heat flux explained by available radiation improved by >10 %, while energy balance closure improved only slightly. This is shown to be mainly due to the average inclination and aspect corresponding largely with the inclination and aspect of the main flux source area in combination with a limited sensitivity of the slope correction to small angular differences in, particularly, inclination and aspect. We conclude with a discussion of limitations of the present approach and future research directions.


Janko M.,Ludwig Maximilians University of Munich | Janko M.,TU Darmstadt | Stark R.W.,Ludwig Maximilians University of Munich | Stark R.W.,TU Darmstadt | And 2 more authors.
Journal of the Royal Society Interface | Year: 2012

Changes in elasticity and structures of red blood cells (RBCs) are important indicators of disease, and this makes them interesting for medical studies. In forensics, blood analyses represent a crucial part of crime scene investigations. For these reasons, the recovery and analysis of blood cells from ancient tissues is of major interest. In this study, we show that RBCs were preserved in Iceman tissue samples for more than 5000 years. The morphological and molecular composition of the blood corpuscle is verified by atomic force microscope and Raman spectroscopy measurements. The cell size and shape approximated those of healthy, dried, recent RBCs. Raman spectra of the ancient corpuscle revealed bands that are characteristic of haemoglobin. Additional vibrational modes typical for other proteinaceous fragments, possibly fibrin, suggested the formation of a blood clot. The band intensities, however, were approximately an order of magnitude weaker than those of recent RBCs. This fact points to a decrease in the RBC-specific metalloprotein haemoglobin and, thus, to a degradation of the cells. Together, the results show the preservation of RBCs in the 5000 year old mummy tissue and give the first insights into their degradation. © 2012 The Royal Society.


News Article | January 15, 2016
Site: www.techtimes.com

The ice mummy Ötzi has provided much information about the Homo Sapiens way of life. Sadly, a new research from the European Academy of Bolzano/Bozen (EURAC) clarified that Ötzi's maternal genetic line is now extinct. The Ötzi iceman lived over 5,300 years ago in the eastern Alps. In 2012, researchers conducted a DNA analysis of Ötzi's Y chromosome, which is transferred from fathers to sons. The 2012 research concluded that Ötzi's paternal line is very much alive. Ötzi's maternal genetic line still has many questions left unanswered. EURAC researchers compared Ötzi's mitochondrial DNA, which is named K1f, with 1,077 samples taken from more populations to conclude the remaining mystery. Sadly, the study found Ötzi's maternal genetic line is now extinct. EURAC researchers also traced the genetic origin of K1f by comparing it to the genetic data of several European Neolithic samples. They theorized that the maternal genetic line originated in the Alps within a population that failed to expand demographically. First author and EURAC biologist Valentina Coia explained that Ötzi's mitochondrial DNA was first analyzed in 1994 but the genetic link between Ötzi's maternal line and other lines found in modern-day populations left many questions unanswered. In 2008, other team also analyzed the Iceman's complete mitochondrial DNA and found it is no longer present in modern populations. But the study didn't clear if the absence was due to lack of sufficient samples or could it be that K1f is already extinct. Coia explained that the 2008 samples only used 85 modern-day population samples taken from the K1 lineage, which also included Ötzi's ancestry. These did not include samples taken from the eastern Alps and just very few from Europe. "To test the two hypotheses, we needed to compare Ötzi's mitochondrial DNA with a larger number of modern samples," said Coia whose team used 1,077 modern-day samples from the K1 lineage. Forty-two samples were taken from the populations in the eastern Alps, which is a first. The study was published in the journal Scientific Reports on Jan. 14.


Brown D.J.A.,University of British Columbia | Brugger H.,European Academy of Bolzano | Boyd J.,Mineral Springs Hospital | Paal P.,Innsbruck Medical University
New England Journal of Medicine | Year: 2012

ACCIDENTAL HYPOTHERMIA (I.E., AN INVOLUNTARY DROP IN CORE BODY temperature to <35°C [95°F]) is a condition associated with significant morbidity and mortality. Each year, approximately 1500 patients in the United States have hypothermia noted on their death certificate; however, the incidence of primary and secondary hypothermia and the associated morbidity and mortality remain unknown. In a single tertiary care center, 14 different rewarming methods were used to treat 84 cases of accidental hypothermia, which reflects the uncertainties about treatment and the potential for complications. Certain treatment approaches are available only in specialized centers, and clarification is needed regarding the choice between transporting a patient to a specialized center and providing treatment locally. Existing recommendations do not include recent developments in rewarming methods nor do they assist with decisions regarding transportation. Copyright © 2012 Massachusetts Medical Society.


Lyding V.,European Academy of Bozen | Lyding V.,European Academy of Bolzano | Genereux M.,McMaster University
Proceedings of the International Conference on Information Visualisation | Year: 2016

This paper presents the visual corpus interface created within the OPATCH project ('Open Platform for access to and Analysis of Textual documents of Cultural Heritage'). The interface combines a set of visualizations for textual data and language features with the aim to support linguistic analysis. The paper describes the choice of visualizations, their interlinking and their integration with a corpus search engine. It discusses challenges related to data handling and usage scenarios and lays out open needs for future work. © 2016 IEEE.


News Article | August 22, 2016
Site: www.rdmag.com

Scientists say Oetzi the Iceman wore clothes made of brown bear pelt and roe deer when he died in the Alps 5,300 years ago. Researchers in Italy used genetic analysis to determine that the two materials were used for Oetzi's fur hat and his leather quiver respectively. Niall O'Sullivan, a researcher at the European Academy of Bolzano, Italy, said the study published Thursday in the journal Scientific Reports also showed that other pieces of Oetzi's clothing came from domesticated animals. The mix of materials suggests the Iceman was adept at using material from domesticated sheep, cattle and goat as well as wild animals to fashion clothes. Oetzi's mummified body has been studied extensively since it was discovered on a glacier near the Italian-Austrian border in 1991. Content Item Type: NewsSummary: Scientists say Oetzi the Iceman wore clothes made of brown bear pelt and roe deer when he died in the Alps 5,300 years ago. Featured Image: Contributed Author: The Associated PressTopics: EvolutionMeta Keywords: Oetzi, brown bear pelt, journal Scientific Reports, leather quiver, domesticated animals, roe deer, domesticated sheep, Niall O'Sullivan, fur hat, genetic analysis, European Academy, Italian-Austrian border, wild animals, Iceman, clothes, Italy, materials, Bolzano, AlpsExclusive: 


Janko M.,Ludwig Maximilians University of Munich | Zink A.,Ludwig Maximilians University of Munich | Zink A.,European Academy of Bolzano | Gigler A.M.,Ludwig Maximilians University of Munich | And 2 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2010

Skin protects the body from pathogens and degradation. Mummified skin in particular is extremely resistant to decomposition. External influences or the action of micro-organisms, however, can degrade the connective tissue and lay the subjacent tissue open. To determine the degree of tissue preservation in mummified human skin and, in particular, the reason for its durability, we investigated the structural integrity of its main protein, type I collagen. We extracted samples from the Neolithic glacier mummy known as 'the Iceman'. Atomic force microscopy (AFM) revealed collagen fibrils that had characteristic banding patterns of 69±5 nm periodicity. Both the microstructure and the ultrastructure of dermal collagen bundles and fibrils were largely unaltered and extremely well preserved by the natural conservation process. Raman spectra of the ancient collagen indicated that there were no significant modifications in the molecular structure. However, AFM nanoindentation measurements showed slight changes in the mechanical behaviour of the fibrils. Young's modulus of single mummified fibrils was 4.1±1.1 GPa, whereas the elasticity of recent collagen averages 3.2±1.0 GPa. The excellent preservation of the collagen indicates that dehydration owing to freeze-drying of the collagen is the main process in mummification and that the influence of the degradation processes can be addressed, even after 5300 years. © 2010 The Royal Society.

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