Categories
Uncategorized

CreaThesis Tabea Huss

Towards a Universal Machine Learning Interatomic Potential for the x Li2S –(100-x) P2S5 Material Class

In this thesis, the aim was to find a method to investigate the structural complexity of the lithium thiophosphate material class and how this influences the lithium-ion conductivity (thus how fast the ions can move through the structure). A machine-learning approach (which replaced a much more computational demanding method) allowed for this. One main finding was that the ionic conductivity in amorphous (thus structures lacking a periodic ordering) is decreased, when many bulky thiophosphate building blocks were present, as they reduce the volume of lithium-ion channels and - other than smaller building blocks - cannot rotate to let the lithium ions pass.

Simplified Abstract

Lithium-ion batteries are so abundant in our daily life, that it is very difficult to imagine a world without them. All portable electric devices are powered by them, and they are by far the most promising technology for the future of automotive mobility. Particularly solid electrolytes are highly investigated in literature right now, as they are inflammable and the battery thus less prone to explosion. Currently, a quest for the best solid electrolyte, which most importantly needs to have a high lithium-ion conductivity, takes place in science. Lithium thiophosphates are a promising material class, containing cheap and earth-abundant materials.

Name:                        Tabea Huss

 

Categories
Uncategorized

Magdalena Bader

Research to improve the quality of proso millet malt for the brewing process OR How to make beer from proso millet malt

My CreaThesis starts with a general overwiew of the brewing process. The actual process is way more complex, but those are the most important steps. Crushed malt is mixed with water and held at several temperatures between round about 50 to 80 °C (depending on the specific procedure and the raw materials). During those rests, enzymes from the malt are degrading several ingredients of the malt, including starch and protein. The starch is broken down into fermentable sugars such as glucose and maltose, which will later be metabolized by the yeast. The mash is separated into solid particles and the remaining liquid which is called wort. The wort is boiled and cooled, and the yeast is added. The yeast ferments the sugars and produces mostly ethanol and carbon dioxide. Now comes the interesting part and simultaneously the problem I tried to tackle in my thesis: Brewers found out that you cannot just use any raw material in the process that is designed for using barley malt. Brewing with proso millet malt for example will lead to nearly no enzymatic degradation of the starch, which will of course lead to a poor fermentation performance and a bad beer. I found out that this is because the optimal working temperatures of enzymes from barley malt and from proso millet malt differ drastically – some from barley malt like it colder, while the same enzymes from proso millet malt like a higher temperature. So, my solution was to adapt the mashing procedure which is designed for barley malt to the temperatures I found in proso millet malt. And it worked! I tried the new procedure out and the results were very promising. But now you might wonder why this is important. We already have a raw material which is almost perfect for brewing beer – barley malt. The problem with barley is that it contains gluten, so people who are allergic to that cannot consume beer made from barley malt. Proso millet is gluten-free – and therefore perfect for brewing gluten-free beer. Also, it is a raw material that you can use in Germany, where the strict regulations of the German purity law apply.

Simplified Abstract

Since the number of celiac disease cases rises globally, the demand for gluten-free beers with proso millet malt as the main ingredient also increases. Yet the problem with proso millet malt is that the wort (= “beer before fermentation”) is lacking quality when being processed the usual way in the brewery. These low-quality worts cause major microbiological and technological problems throughout the whole production process. Therefore, the production of the wort, which is called mashing, needs to be adjusted. During the mashing crushed malt is mixed with water and this mixture is then heated to different temperatures (e.g. 50 to 78 °C for barley malt). There are several temperature rests during which the enzymes in the mash are degrading the malt ingredients (starch, proteins etc.). The most important enzymatic degradation is the breakdown of starch into fermentable sugars. It is very important that the rests are being held at special temperatures, since every enzyme has its optimal working temperature.

In my thesis I found out that the optimal working temperatures of proso millet malt enzymes differ strongly from the ones found in barley malt. Therefore, brewing with proso millet malt requires a mashing procedure especially designed for this special raw material. With my findings about the ideal malting conditions for proso millet and about the special enzyme characteristics of proso millet malt I designed such a mashing procedure. With this adapted process, producing a high-quality wort with proso millet malt was finally achieved. The satisfactory wort test results lead to the conclusion that proso millet is a suitable gluten-free raw material for the brewing process.

 

Name:                        Magdalena Bader


Categories
Uncategorized

Dominik Wernberger

Optimization of the weight distribution of VbS modules on the aCar

My CreaThesis is a photoshopped picture of the aCar drifting on the Nürburgring Nordschleife, a famous German racetrack. Weight distribution is an important factor in drifting as it prevents the car from tipping over as well as making the drift more controllable. Heavy load in the rear gives you plenty of grip but makes the drift very hard to control as soon as traction is lost while weight on the front axle gives you a lot of grip from steering when holding the drift. But drifting isn’t really a topic for the aCar as a utility car with low power and all wheel drive. For a utility vehicle the goal is to load as much payload as possible in normal driving conditions, in case of the aCar in road conditions from Ethiopia and Côte d'Ivoire. This Antithesis makes the CreaThesis an eye-catching picture that stops people from scrolling past and creates an interest in the topic of the thesis and the aCar as a project.

Simplified Abstract

My Bachelor Thesis described influencing and limiting factors for the weight distribution of the aCar.

The aCar mobility project is a project of FTM (Institute of Automotive Technology TUM) that develops use cases for a small battery-electric pickup truck (BEV) with focus on mobility in Sub-Saharan Africa. Being battery-powered and therefore able to deliver electric power everywhere gives many new possibilities of usage.

I considered surrounding conditions like maximum slopes and weight of the driver and a possible trailer and the boundaries the manufacturer of the vehicle sets on axle loads etc.

This ended up in a model you can feed with basic vehicle data and the weight and position of objects you want to load to the vehicle. As a result you get exceedances of limit values.

Moreover the thesis examined how additional load influences the BEVs range and considered possibilities to install a mounting rack on the vehicle.

This work feeds into the development of modules like a mobile clinic and many other vehicle-based services (VbS) to be developed based on the aCar as a multi-functional vehicle.

Name:                        Dominik Wernberger

Categories
Uncategorized

CreaThesis Matthias Harr

Material properties of copper

The comic shows two men that are testing how hard they can pull on both sides of a 3D printed copper stick before it breaks. This comic strip was chosen because in my master thesis I wanted to test under which traction a 3D printed copper stick would break. It is important to know the material properties e.g., for building electronic parts.

Simplified Abstract

For selective laser beam melting (a form of socalled 3D printing) the mechanical properties of printed components for pure copper are not known so far. However, through tensile teststhe determination of tensile strength and elongation behavior of copper is possible. Therefore, the goal of my master Thesis was i) to find suitable combinations of parameters to produce standardized 3D printed copper sticks which could be used in tension tests and ii) to determine the traction force at which the copper stick would break. First, the tensile samples had to meet certain requirements such as an optimal shape and density to obtain meaningful
results. For example, the density had to reach a minimum value of 99.5% which means that the copper stick had to be of 99.5% pure copper. Furthermore, the copper sticks had to be homogenous without any air inclusions and be free from visible flaws.
To achieve my goals, I printed the copper samples with a 3D machine which turned out to be the real difficulty within my master Thesis. Under the given conditions it was almost impossible to produce good samples. Hence, I wasn ́t able to complete the first step and unfortunately couldn ́t measure the tension needed to break my samples. Research is not always easy and sometimes you have to take one step back. In my case this means that still a lot of research must be conducted on 3D printing of pure copper before using 3D printed copper in electronics or other industrial products.

 

Name:                        Matthias Harr

Categories
Uncategorized

CreaThesis Annika Neuhaus

The Integration of a new silverback male into a group of female gorillas

Simplified Abstract

In this study, I observed the integration of a new silverback into a four-member female group of the western lowland Gorilla (Gorilla gorilla gorilla) in the Nuremberg Zoo. I paid attention particularly to the changing daily rhythms and behavior, as well as the aggression of single individuals and the overall aggression of the group. On 37 days, for 8 hours each, I noted every three minutes, where in the enclosure the five gorillas (i.e., Lena, Bianka, Habibu, Louna and Thomas) were and what behavior they showed. I categorized behavior into several different groups such as staying by oneself, locomotion, playing, sexual behavior, aggressive behavior, social behavior, problematic/stereotypic behavior, and feeding. The daily rhythm and the percentage of categorized behaviors shifted after the arrival of the male gorilla. The group regained a stable rhythm in the later phases, but it differed from that at the beginning of the observation. The frequency of aggression and dominance increased in the group after the introduction of the male. The group structure changed such that Lena gave her leadership to Thomas and Louna chose this older female instead of Bianka as reference animal. Aggression among females dropped once the silverback joined the group and their cohesion increased. The goal was to document the response of the animals during the introduction, to broaden the experience with these highly social animals.

Name:                        Annika Neuhaus

Field of study:          Biology

 

 

 

Categories
Uncategorized

CreaThesis Theresa Franz

From archaeal to eucaryotic proteasomes: Biochemical and structural studies on assembly intermediates and proteasomes with intermediate complexity

X-ray crystallography is a method used to determine the atomic structure of complex biomolecules such as proteins. This requires protein crystals that are illuminated with X-rays. The resulting diffraction patterns can be used to determine the 3D structure of the molecules that form the crystal. For this purpose, the proteins must be isolated and purified using molecular biological and protein chemical methods before they can form crystals that can not only be highly complex but also stunningly beautiful.

Simplified Abstract

In this thesis, proteasomes – enzymes that break down proteins in the body – were studied. For this purpose, different mutations were introduced into the proteins that form the proteasomes, and their effects on function and structure were analyzed. To this end, the proteins were first produced in bacteria and then purified to obtain the desired protein in such a high concentration that it formed crystals under certain conditions.

This way, it was possible to determine which mutations reduced the activity of the proteasomes strongly and thus which residues or amino acids are particularly important for the ability of the proteasome to cleave proteins. We also tested which conditions (buffer, pH, protein concentrations, etc.) led to favorable results during purification and crystallization for all the individual proteins and which proteins were not capable of forming crystals on their own.

Name:                        Theresa Franz

Field of study:          Biochemistry

Supervisor:               Dr. Eva Huber 

Chair:                          Chair of Biochemistry

Categories
Uncategorized

CreaThesis Nico Michel.

Flight control equations in a simple way

Abstracting a physical existing thing with a large model is used to put the world into equations and enables engineers to try out things without risk or high cost. Abstracting this model again to a smaller size enables to focus on specialthings easily.

Simplified Abstract

The task of the thesis was to investigate the influence of nonlinear coupling effects on the longitudinal flight dynamics of a Vertical Take-Off and Landing Vehicle (VTOL), a special type of drone. During flight tests, my supervisors project group discovered undesired flight behavior of their real existing VTOL, which did not appear in the full scale, multi degree of freedom simulation model. To examine the correlations between the different actuators, my task was to create a simplified model of the longitudinal dynamics of the VTOL, control it with the applied control algorithm and try to find out the connections that cause the undesired flight behavior. The big aim was to implement counter measures to improve the flight behavior and supply it to the project groups model.

Name:                        Nico Michel

Field of study:          Mechanical Engineering/ Aerospace

Supervisor:               Prof. Holzapfel

Chair:                         Institute of Flight System Dynamics

Name:                        Dominik Wernberger

Name:                        Dominik Wernberger

Categories
Uncategorized

Creathesis Veronika Bauer

Physical Unclonable Functions (PUFs)

Transparent objects that contain internal disorder can be lighted with a laser beam in order to create a speckle pattern unique to the object. These objects can be used in the context of IT Security..

Simplified Abstract

A PUF, short for physical unclonable function, is an object containing an internally disordered structure either by default or by design. Various objects contain internal disorder in their nanoscale structure like the fibers of a piece of paper, slight manufacturing differences on computer chips or even the structured surface of a wall. Each piece is unique and cannot be physically cloned, not even by its manufacturer. While these slight differences are often seen as a nuisance, these can be exploited for IT Security purposes. If an external stimulus is introduced to such an object, e.g. a laser beam to a transparent object, it reacts in a unique way, e.g. by creating a speckle pattern. If the angle of the laser beam or its position are changed, different pattern emerge. Thus, various stimuli, called challenges, can be used to create different outputs, referred to as responses. If the same challenge is introduced to such a PUF, the same response is outputted all the time, whereas changes within the PUF or the use of a different PUF lead to a different response. Hence, knowing this unique challenge-response behavior, one is able to identify the PUF and detect changes within the PUF. This feature can be exploited for various cryptographic protocols like authentication purposes. Image you know that your best friend owns a PUF and you know how this PUF behaves when a laser beam lights this PUF. Then, you are able to identify your best friend by just examining the PUF’s behavior. Thus, this PUF can be seen as a secure tag or label. This technique can be used to counterfeit pirated products like medicine by placing a PUF on the packaging. Forgers are not able to physically clone this PUF which is why, e.g. a pharmacy is able to check the product’s authenticity.

Name:                        Veronika Bauer

Field of study:          Informatics

Supervisor:                Prof. Dr. Dieter Kranzlmüller, Prof. Dr. Dr. Ulrich Rührmair, M.Sc. Steffen Illium

Chair:                          Institute of Informatics LMU Munich

Categories
Uncategorized

CreaThesis Andrea Schittenhelm

Sensory-processing sensitivity – a possible predictor for shooting performance and state orientation? An investigation of the influence of sensitivity on shooting performance and personality variables

The picture shows an open photography aperture. It was chosen as a metaphor for the differences amongst humans regarding their sensitivity to environmental cues. Some humans do have a wide open “aperture” (are very sensitive to environmental cues), other human apertures are rather closed. This CreaThesis aims to illustrate the theory behind the thesis..

Simplified Abstract

Aim of the bachelor thesis was to investigate if sensory-processing sensitivity could have a disadvantage or an advantage in sport shooting performance. Additionally, the study did also investigate if sensory-processing sensitivity may have a correlation with the personality variable state orientation. To evaluate these questions, an online survey with the German version of the Highly Sensitive Person Scale (HSPS-GS), as well as the German version of the Action Control Scale (HOSP) was conducted. Results revealed differences in sensitivity between high-performer and low-performer in shooting sports for men (p = .019, d = .26) but not for women (p = .864, d = -.02). Striking was that in the study sample included distinctly less persons that reached the high scorers on the HSPS-GS, than described in the literature. This means, that there were almost no highly sensitive persons in the shooting sample. A moderate correlation between sensitivity and state orientation was found. These results, especially the absence of high scorers, is perhaps an indicator for high sensitivity as a possible disadvantage in competitive shooting sports. 

Name:                        Andrea Schittenhelm

Field of study:          Sport Science

Supervisor:                Prof. Dr. Jürgen Beckmann

Chair:                          Chair of Sport Psychology

Categories
Uncategorized

CreaThesis Philipp Strobl

The role of Stearoyl-CoA desaturase-1 (SCD1) and Glutathione Peroxidase 8 (GPX8) in Lipotoxicity

The picture displays how an unsaturated fatty acid (blue) protectively throws itself in front of a cell to save it from a saturated fatty acid (red). This scenery was chosen because it was shown in part of my bachelor thesis that high amounts of saturated fatty acids trigger cell death in murine cells, but this effect can be prevented by the simultaneous addition of unsaturated fatty acids.

Simplified Abstract

The aim of my thesis was to investigate the role of two enzymes in a process called lipotoxicity. Lipotoxicity is a metabolic syndrome in which high concentrations of free fatty acids lead to cell dysfunction and subsequent cell death. However, how these free fatty acids trigger this cytotoxicity is not yet fully understood

One of the enzymes studied in this thesis (SCD1) is necessary for the conversion of saturated to unsaturated fatty acids, the other (GPX8) is thought to play a role in maintaining a healthy environment in the cell. To understand the role of these enzymes in lipotoxicity in more detail, they were made non-functional in cultured mouse cells by a so-called “knockout”. The subsequent treatment of these cells with fatty acids and the analysis of the following cell reactions should provide information about their role in lipotoxicity.

This work demonstrated that both GPX8 and SCD1 play a major role in protection against lipotoxicity. It could be shown that cell death in mouse cells could be induced by the addition of elevated concentrations of saturated fatty acids but could be prevented by the simultaneous addition of unsaturated fatty acids. The “knockout” of the two enzymes led to cell death at significantly lower concentrations of saturated fatty acids. By analyzing different cellular pathways, answers could be found how this lipotoxicity protection is ensured by the enzymes.

Name:                        Philipp Strobl

Field of study:          Biology

Supervisor:                Dr. Marcus Conrad

Chair:                          Helmholtz-Zentrum München