Heiko Briesen

Prof. Heiko Briesen

orcid

Research Focus & Metrics

Academic Career Length

29Years (1998-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
16 February 2017 in Molecular Physics
Verified
Journal Article
Closed access
SMSebastian Mainberger
Sebastian Mainberger
MKMoritz Kindlein
Moritz Kindlein
FBFranziska Bezold
Franziska Bezold
EEEkaterina Elts
Ekaterina Elts
MMMirjana Minceva
Mirjana Minceva
HBHeiko Briesen
Heiko Briesen
Deep eutectic solvents (DES) have gained a reputation as inexpensive and easy to handle ionic liquid analogues. This work employs molecular dynamics (MD) to simulate a variety of DES. The hydrogen bond acceptor (HBA) choline chloride was paired with the hydrogen bond donors (HBD) glycerol, 1,4-butanediol, and levulinic acid. Levulinic acid was also paired with the zwitterionic HBA betaine. In order to evaluate the reliability of data MD simulations can provide for DES, two force fields were compared: the Merck Molecular Force Field and the General Amber Force Field with two different sets of partial charges for the latter. The force fields were evaluated by comparing available experimental thermodynamic and transport properties against simulated values. Structural analysis was performed on the eutectic systems and compared to non-eutectic compositions. All force fields could be validated against certain experimental properties, but performance varied depending on the system and property in question. While extensive hydrogen bonding was found for all systems, details about the contribution of individual groups strongly varied among force fields. Interaction potentials revealed that HBA–HBA interactions weaken linearly with increasing HBD ratio, while HBD–HBD interactions grew disproportionally in magnitude, which might hint at the eutectic composition of a system.

23 August 2021 in Fungal Biology and Biotechnology
Verified
Journal Article
Open access
PDF file
VMVera Meyer
Vera Meyer
TCTimothy Cairns
Timothy Cairns
LBLars Barthel
Lars Barthel
Rudibert KingRudibert King
Rudibert King
PKPhilipp Kunz
Philipp Kunz
RKRainer Krull
Rainer Krull
Filamentous fungal cell factories are efficient producers of platform chemicals, proteins, enzymes and natural products. Stirred-tank bioreactors up to a scale of several hundred m³ are commonly used for their cultivation. Fungal hyphae self-assemble into various cellular macromorphologies ranging from dispersed mycelia, loose clumps, to compact pellets. Development of these macromorphologies is so far unpredictable but strongly impacts productivities of fungal bioprocesses. Depending on the strain and the desired product, the morphological forms vary, but no strain- or product-related correlations currently exist to improve process understanding of fungal production systems. However, novel genomic, genetic, metabolic, imaging and modelling tools have recently been established that will provide fundamental new insights into filamentous fungal growth and how it is balanced with product formation. In this primer, these tools will be highlighted and their revolutionary impact on rational morphology engineering and bioprocess control will be discussed.

1 January 2006 in Chemical Engineering Science
Verified
Journal Article
Closed access
HBHeiko Briesen
Heiko Briesen

1 November 2009 in Journal of Colloid and Interface Science
Verified
Journal Article
Closed access
VBVolker Becker
Volker Becker
ESEva Schlauch
Eva Schlauch
MBMarek Behr
Marek Behr
HBHeiko Briesen
Heiko Briesen

20 April 2017 in Ecosphere
Verified
Journal Article
Open access
PDF file
JEJan Engel
Jan Engel
LHLionel Hertzog
Lionel Hertzog
JTJulia Tiede
Julia Tiede
CWCameron Wagg
Cameron Wagg
AEAnne Ebeling
Anne Ebeling
WWWolfgang W. Weisser
Wolfgang W. Weisser
The diversity and community composition of ground arthropods is routinely analyzed by pitfall trap sampling, which is a cost‐ and time‐effective method to gather large numbers of replicates but also known to generate data that are biased by species‐specific differences in locomotory activity. Previous studies have looked at factors that influence the sampling bias. These studies, however, were limited to one or few species and did rarely quantify how the species‐specific sampling bias shapes community‐level diversity metrics. In this study, we systematically quantify the species‐specific and community‐level sampling bias with an allometric individual‐based model that simulates movement and pitfall sampling of 10 generic ground arthropod species differing in body mass. We perform multiple simulation experiments covering different scenarios of pitfall trap number, spatial trap arrangement, temperature, and population density. We show that the sampling bias decreased strongly with increasing body mass, temperature, and pitfall trap number, while population density had no effect and trap arrangement only had little effect. The average movement speed of a species in the field integrates body mass and temperature effects and could be used to derive reliable estimates of absolute species abundance. We demonstrate how unbiased relative species abundance can be derived using correction factors that need only information on species body mass. We find that community‐level diversity metrics are sensitive to the particular community structure, namely the relation between body mass and relative abundance across species. Generally, pitfall trap sampling flattens the rank‐abundance distribution and leads to overestimations of ground arthropod Shannon diversity. We conclude that the correction of the species‐specific pitfall trap sampling bias is necessary for the reliability of conclusions drawn from ground arthropod field studies. We propose bias correction is a manageable task using either body mass to derive unbiased relative abundance or the average speed to derive reliable estimates of absolute abundance from pitfall trap sampling.

1 December 1998 in Chemical Engineering Science
Verified
Journal Article
Closed access
HBHeiko Briesen
Heiko Briesen
AFAndre’ Fuhrmann
Andre’ Fuhrmann
SPSotiris E. Pratsinis
Sotiris E. Pratsinis