TY  - JOUR
A1  - Blanchard, Gilles
A1  - Zadorozhnyi, Oleksandr
T1  - Concentration of weakly dependent Banach-valued sums and applications to statistical learning methods
JF  - Bernoulli : official journal of the Bernoulli Society for Mathematical Statistics and Probability
N2  - We obtain a Bernstein-type inequality for sums of Banach-valued random variables satisfying a weak dependence assumption of general type and under certain smoothness assumptions of the underlying Banach norm. We use this inequality in order to investigate in the asymptotical regime the error upper bounds for the broad family of spectral regularization methods for reproducing kernel decision rules, when trained on a sample coming from a tau-mixing process.
KW  - Banach-valued process
KW  - Bernstein inequality
KW  - concentration
KW  - spectral regularization
KW  - weak dependence
Y1  - 2019
U6  - https://doi.org/10.3150/18-BEJ1095
SN  - 1350-7265
SN  - 1573-9759
VL  - 25
IS  - 4B
SP  - 3421
EP  - 3458
PB  - International Statistical Institute
CY  - Voorburg
ER  - 
TY  - JOUR
A1  - Liu, Qi
A1  - Kämpf, Horst
A1  - Bussert, Robert
A1  - Krauze, Patryk
A1  - Horn, Fabian
A1  - Nickschick, Tobias
A1  - Plessen, Birgit
A1  - Wagner, Dirk
A1  - Alawi, Mashal
T1  - Influence of CO2 degassing on the microbial community in a dry mofette field in Hartoušov, Czech Republic (Western Eger Rift)
JF  - Frontiers in Microbiology
N2  - The Cheb Basin (CZ) is a shallow Neogene intracontinental basin filled with fluvial and lacustrine sediments that is located in the western part of the Eger Rift. The basin is situated in a seismically active area and is characterized by diffuse degassing of mantle-derived CO2 in mofette fields. The Hartousov mofette field shows a daily CO2 flux of 23-97 tons of CO2 released over an area of 0.35 km(2) and a soil gas concentration of up to 100% CO2. The present study aims to explore the geo-bio interactions provoked by the influence of elevated CO2 concentrations on the geochemistry and microbial community of soils and sediments. To sample the strata, two 3-m cores were recovered. One core stems from the center of the degassing structure, whereas the other core was taken 8 m from the ENE and served as an undisturbed reference site. The sites were compared regarding their geochemical features, microbial abundances, and microbial community structures. The mofette site is characterized by a low pH and high TOC/sulfate contents. Striking differences in the microbial community highlight the substantial impact of elevated CO2 concentrations and their associated side effects on microbial processes. The abundance of microbes did not show a typical decrease with depth, indicating that the uprising CO2-rich fluid provides sufficient substrate for chemolithoautotrophic anaerobic microorganisms. Illumine MiSeq sequencing of the 16S rRNA genes and multivariate statistics reveals that the pH strongly influences microbial composition and explains around 38.7% of the variance at the mofette site and 22.4% of the variance between the mofette site and the undisturbed reference site. Accordingly, acidophilic microorganisms (e.g., OTUs assigned to Acidobacteriaceae and Acidithiobacillus) displayed a much higher relative abundance at the mofette site than at the reference site. The microbial community at the mofette site is characterized by a high relative abundance of methanogens and taxa involved in sulfur cycling. The present study provides intriguing insights into microbial life and geo-bio interactions in an active seismic region dominated by emanating mantle-derived CO2-rich fluids, and thereby builds the basis for further studies, e.g., focusing on the functional repertoire of the communities. However, it remains open if the observed patterns can be generalized for different time-points or sites.
KW  - geo–bio interaction
KW  - elevated CO2
KW  - concentration
KW  - paleo-sediment
KW  - deep biosphere
KW  - acidophilic microorganisms
KW  - Acidobacteriaceae
KW  - Acidithiobacillus
KW  - Acidothermus
Y1  - 2018
U6  - https://doi.org/10.3389/fmicb.2018.02787
SN  - 1664-302X
VL  - 9
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - THES
A1  - Anielski, Alexander
T1  - Entwicklung einer mikrofluidischen, adaptiv geregelten Messapparatur zur quantitativen Untersuchung von Chemotaxis mit Hilfe der Flussfotolyse
KW  - Flussfotolyse
KW  - Konzentration
KW  - Chemotaxis
KW  - Mikrokanal
KW  - Dictyostelium
KW  - flow photolysis
KW  - concentration
KW  - chemotaxis
KW  - microchannel
KW  - Dictyostelium
Y1  - 2015
ER  -