Beitrag zur Physiologie des N. Vagus. I. Mitteilung : Uber die Funktion des N. vagus auf die Atmung

1) Der Gaswechsel und der Respirationsquotient des Einrecurrenskaninchens (Lungenvagusfreienkaninchens, vgl. II. Mitteilung) scheint fast keinen Unterschied im Vergleich mit den normalen und Kontrolltieren zu zeigen. Beim Versuch wurde der von Saeki (1931) am hiesigen Institut verbesserte Haldensche Apparat angewendet. Aus diesem Resultat gelangt der Verfasser zu dem Schluss, dass die Ausschaltung des Lungenvagus auf den Gaswechsel und den Respirationsquotienten fast keinen Einfluss ausubt. 2) Bei der Durchschneidungsmethode, die sicher den Lungenvagus auschaltet, tritt immer die typische Vagusatmung auf. 3) Was die Vagusatmung des Einrecurrenskaninchens nach der Operation betrifft, so kehrt wieder allmahlich im Verlauf der Zeit ersichtlich der normale Atmungszustand zuruck, aber durch eine leichte Storung, z. B. durch die Anlegung der Gasmaske, kann die typische Vagusatmung hervorgerufen werden. Um an wiedererholte Erhaltung des normalen Atmungszustandes nach der Ausschaltung des Lungenvagus zu denken, muss man voraussetzen, dass es anstatt des Lungenvagus noch einen anderen Regulations-mechanismus fur den normalen Atmungszustand geben; falls der Regulationsmechanismus durch eine leichte Storung gestort wird, tritt die Vagusatmung auf. Es ist sehr schwer zu denken, an welchem Ort und auf welche Weise die Regulation ausgeubt wird, aber der Verfasser vermutet, dass das Atemzentrum durch die centripetalen Impulse von uberangestrengtem Atemmuskel und Zwerchfell nach der Lungenvagusaus-schaltung wieder die regulatorische centrifugale Wirkung zum Atemmuskel und Zwerchfell sendet, wodurch der Regulationsmechanismus entsteht. 4) Die Abnahme der Atmungszahl nach der doppelseitigen Vagotomie am Halse kann nicht durch die Schafersche Glottislahmungstheorie oder Hymansche Aorten-Sinusnervenlahmungstheorie erklart werden, sondern durch die Ausschaltung des Lungen-vagus selbst. 5) Beim Einrecurrenskaninchen sieht man keine Apnoe beim Einblasen der Lunge. Es gilt als eine Bestatigung dafur, dass alle Vagusaste nach der Lunge

Bioproduction of the Recombinant Sweet Protein Thaumatin: Current State of the Art and Perspectives

There is currently a worldwide trend to reduce sugar consumption. This trend is mostly met by the use of artificial non-nutritive sweeteners. However, these sweeteners have also been proven to have adverse health effects such as dizziness, headaches, gastrointestinal issues, and mood changes for aspartame. One of the solutions lies in the commercialization of sweet proteins, which are not associated with adverse health effects. Of these proteins, thaumatin is one of the most studied and most promising alternatives for sugars and artificial sweeteners. Since the natural production of these proteins is often too expensive, biochemical production methods are currently under investigation. With these methods, recombinant DNA technology is used for the production of sweet proteins in a host organism. The most promising host known today is the methylotrophic yeast, Pichia pastoris. This yeast has a tightly regulated methanol-induced promotor, allowing a good control over the recombinant protein production. Great efforts have been undertaken for improving the yields and purities of thaumatin productions, but a further optimization is still desired. This review focuses on (i) the motivation for using and producing sweet proteins, (ii) the properties and history of thaumatin, (iii) the production of recombinant sweet proteins, and (iv) future possibilities for process optimization based on a systems biology approach

Extending multilevel statistical entropy analysis towards plastic recyclability prediction

Multilevel statistical entropy analysis (SEA) is a method that has been recently proposed to evaluate circular economy strategies on the material, component and product levels to identify critical stages of resource and functionality losses. However, the comparison of technological alternatives may be difficult, and equal entropies do not necessarily correspond with equal recyclability. A coupling with energy consumption aspects is strongly recommended but largely lacking. The aim of this paper is to improve the multilevel SEA method to reliably assess the recyclability of plastics. Therefore, the multilevel SEA method is first applied to a conceptual case study of a fictitious bag filled with plastics, and the possibilities and limitations of the method are highlighted. Subsequently, it is proposed to extend the method with the computation of the relative decomposition energies of components and products. Finally, two recyclability metrics are proposed. A plastic waste collection bag filled with plastic bottles is used as a case study to illustrate the potential of the developed extended multilevel SEA method. The proposed extension allows us to estimate the recyclability of plastics. In future work, this method will be refined and other potential extensions will be studied together with applications to real-life plastic products and plastic waste streams

Comparing design of experiments and optimal experimental design techniques for modelling the microbial growth rate under static environmental conditions

Building secondary models that describe the growth rate as a function of multiple environmental conditions is often very labour intensive and costly. As such, the current research aims to assist in decreasing the required experimental effort by studying the efficacy of both design of experiments (DOE) and optimal experimental designs (OED) techniques. This is the first research in predictive microbiology (i) to make a comparison of these techniques based on the (relative) model prediction uncertainty of the obtained models and (ii) to compare OED criteria for the design of experiments with static (instead of dynamic) environmental conditions. A comparison of the DOE techniques demonstrated that the inscribed central composite design and full factorial design were most suitable. Five conventional and two tailor made OED criteria were tested. The commonly used D-criterion performed best out of the conventional designs and almost equally well as the best of the dedicated criteria. Moreover, the modelling results of the D-criterion were less dependent on the experimental variability and differences in the microbial response than the two selected DOE techniques. Finally, it was proven that solving the optimisation of the D-criterion can be made more efficient by considering the sensitivities of the growth rate relative to its value as Jacobian matrix instead of the sensitivities of the cell density measurements.status: publishe

A tutorial on uncertainty propagation techniques for predictive microbiology models: A critical analysis of state-of-the-art techniques

Building mathematical models in predictive microbiology is a data driven science. As such, the experimental data (and its uncertainty) has an influence on the final predictions and even on the calculation of the model prediction uncertainty. Therefore, the current research studies the influence of both the parameter estimation and uncertainty propagation method on the calculation of the model prediction uncertainty. The study is intended as well as a tutorial to uncertainty propagation techniques for researchers in (predictive) microbiology. To this end, an in silico case study was applied in which the effect of temperature on the microbial growth rate was modelled and used to make simulations for a temperature profile that is characterised by variability. The comparison of the parameter estimation methods demonstrated that the one-step method yields more accurate and precise calculations of the model prediction uncertainty than the two-step method. Four uncertainty propagation methods were assessed. The current work assesses the applicability of these techniques by considering the effect of experimental uncertainty and model input uncertainty. The linear approximation was demonstrated not always to provide reliable results. The Monte Carlo method was computationally very intensive, compared to its competitors. Polynomial chaos expansion was computationally efficient and accurate but is relatively complex to implement. Finally, the sigma point method was preferred as it is (i) computationally efficient, (ii) robust with respect to experimental uncertainty and (iii) easily implemented.status: publishe

Coordinating active distribution networks with multi-microgrids : an ADMM-based decentralized adjustable robust operation model

This paper proposes a decentralized adjustable robust operation model achieving the coordinated operation between an active distribution network (ADN) and microgrids (MGs). Thanks to the autonomous characteristic and heterogeneity of the individual agents in ADNs with multi-MGs, we develop a tailored alternating direction method of multipliers (ADMM)based fully decentralized framework. The linear decision rules are utilized to reformulate the microgrid two-stage adjustable robust operation problem as a computationally tractable solution such that the proposed adjustable robust extension of decentralized ADMM is capable of handling renewable energy uncertainties. The numerical results illustrate the effectiveness of the proposed model