Predictive monitoring of shake flask cultures with online estimated growth models

Simplicity renders shake flasks ideal for strain selection and substrate optimization in biotechnology. Uncertainty during initial experiments may, however, cause adverse growth conditions and mislead conclusions. Using growth models for online predictions of future biomass (BM) and the arrival of critical events like low dissolved oxygen (DO) levels or when to harvest is hence important to optimize protocols. Established knowledge that unfavorable metabolites of growing microorganisms interfere with the substrate suggests that growth dynamics and, as a consequence, the growth model parameters may vary in the course of an experiment. Predictive monitoring of shake flask cultures will therefore benefit from estimating growth model parameters in an online and adaptive manner. This paper evaluates a newly developed particle filter (PF) which is specifically tailored to the requirements of biotechnological shake flask experiments. By combining stationary accuracy with fast adaptation to change the proposed PF estimates time-varying growth model parameters from iteratively measured BM and DO sensor signals in an optimal manner. Such proposition of inferring time varying parameters of Gompertz and Logistic growth models is to our best knowledge novel and here for the first time assessed for predictive monitoring of Escherichia coli (E. coli) shake flask experiments. Assessments that mimic real-time predictions of BM and DO levels under previously untested growth conditions demonstrate the efficacy of the approach. After allowing for an initialization phase where the PF learns appropriate model parameters, we obtain accurate predictions of future BM and DO levels and important temporal characteristics like when to harvest. Statically parameterized growth models that represent the dynamics of a specific setting will in general provide poor characterizations of the dynamics when we change strain or substrate. The proposed approach is thus an important innovation for scientists working on strain characterization and substrate optimization as providing accurate forecasts will improve reproducibility and efficiency in early-stage bioprocess development

Socio-political and Environmental Implications of the Israeli-Palestinian Water Conflict

Palestinians have distinctly different water relations from Israelis due to limited participation in environmental policy, the politics of Zionist occupation, and a de facto shortage due to Israeli diversion of the upper Jordan River. I seek to determine if water can be equitably distributed between its stakeholders, posing the question: Is water scarcity a socio-political construction perpetuated by the politics of Israeli rule, or is there truly not enough water to satisfy demand? I will discuss the uses and policies that allow for this depletion as well as the unequal distribution of the Jordan River resources within the divided Israeli state, focusing on the acute disadvantage faced by Palestinians as they consume amounts determined inadequate by international standards. Israel\u27s water crisis will be scrutinized through environmental, historical, and socio-political lenses to determine the forces of conflict and the possibilities for alleviation

Of Canucks and other myths

Kanada ist bekannt für seine weiten und unberührten Naturlandschaften, für seine vielseitige und heterogene Kultur und für die bekannte Freundlichkeit der Einwohner. Diese ideologisch gefärbten Annahmen kreieren ein symbolisches Konstrukt bestehend aus gewissen Vorstellungen und letztendlich wird dadurch die Basis für eine kanadische Kultur und den damit assoziierten Verhaltensmustern (‚Canadianness‘) gelegt. Diese kulturellen Muster, welche im alltäglichen Leben sichtbar sind, lassen eine ganze Kulturlandschaft entstehen, die sich in den Bereichen Sport, Kunst und natürlich in den Aktivitäten der kanadischen Bevölkerung widerspiegelt. In Essex County und Roughneck, zwei ‚graphic novels‘ geschrieben und gezeichnet vom kanadischen Autor Jeff Lemire, wurden viele dieser kulturellen Praktiken in Form von einer fiktionalen Geschichte aufgegriffen und eröffnen wertvolle Einblicke in die Auffassung von kanadischer Kultur. Auch wenn jedes Werk verschiedene Figuren und Charaktere behandelt, gleichen sich die Themen von der Suche nach Zugehörigkeit und Gemeinschaft. Diese Diplomarbeit versucht nun am Beispiel dieser beiden Werke die Darstellung und Auffassung kanadischer Identität zu dekonstruieren und deren Aufbau zu beschreiben. Dieser Prozess umfasst sowohl die Frage nach Identitäts- und Zugehörigkeitsgefühlen als auch die Beziehung von Gewalt und Intimität. Zusätzlich wird auch der Einfluss von Eishockey auf dieses Kulturverständnis analysiert werden. Durch die Analyse gewisser Zeit- und Ortsdarstellungen und der Miteinbeziehung von Kategorien wie Herkunft und Identität, die sowohl auf Bild- als auch auf Textebene stattfinden wird, wird sich zeigen, wie stereotypische kanadische Verhaltensmuster (‚Canadianness‘) erzeugt und abgebildet werden. Letztlich wird sich zeigen, dass dies analysierten Verhaltensmuster auf komplexen und vielschichtigen kulturellen Konstrukten beruhen, welche beide Bücher durchziehen.Canada as a nation is often recognized for its pristine and vast nature, for its diverse and heterogeneous culture, and for the alleged kindness of its inhabitants. Those ideological assumptions create a symbolic body of ideas and, hence, the basis of what most people understand as Canadian culture or Canadianness. These ideas are encountered in the practices of everyday life, establishing a cultural landscape mirrored in sports, art, and, essentially, in every social activity. In Essex County and Roughneck, two graphic novels written and drawn by Canadian author Jeff Lemire, numerous of those practices are compressed into a fictional story that offers many deep insights into the depiction of Canadian culture. While each work focuses on different characters, the main themes and motifs of community and the search for a sense of belonging coincide. This thesis approaches these two works by deconstructing and describing the notion of Canadian identity and, thus, offers clarification of the various ways in which cultural concepts are created. In this process, questions of identity and community as well as the relationship between intimacy and violence are just as important as the analysis of the influential game of hockey and its impact on Canadian culture. A detailed discussion of time and settings as well as of race and identity on both story and image level will provide a comprehensive outline of how Canadianness is constructed and established as a natural concept. Ultimately, those results will define Canadianness as a highly complex and multilayered ideological construction, which constitutes both graphic novels