Scale-Up and Scale-Down Methodologies for Bioreactors

Bioreactors ◽  
2016 ◽  
pp. 323-354 ◽  
Author(s):  
Peter Neubauer ◽  
Stefan Junne
Keyword(s):  
Scale Up ◽  
2020 ◽  
Vol 30 (11) ◽  
pp. 1588-1594
Author(s):  
Ogochukwu J. Sokunbi ◽  
Ogadinma Mgbajah ◽  
Augustine Olugbemi ◽  
Bassey O. Udom ◽  
Ariyo Idowu ◽  
...  

AbstractThe COVID-19 pandemic is currently ravaging the globe and the African continent is not left out. While the direct effects of the pandemic in regard to morbidity and mortality appear to be more significant in the developed world, the indirect harmful effects on already insufficient healthcare infrastructure on the African continent would in the long term be more detrimental to the populace. Women and children form a significant vulnerable population in underserved areas such as the sub-Saharan region, and expectedly will experience the disadvantages of limited healthcare coverage which is a major fall out of the pandemic. Paediatric cardiac services that are already sparse in various sub-Saharan countries are not left out of this downsizing. Restrictions on international travel for patients out of the continent to seek medical care and for international experts into the continent for regular mission programmes leave few options for children with cardiac defects to get the much-needed care.There is a need for a region-adapted guideline to scale-up services to cater for more children with congenital heart disease (CHD) while providing a safe environment for healthcare workers, patients, and their caregivers. This article outlines measures adapted to maintain paediatric cardiac care in a sub-Saharan tertiary centre in Nigeria during the COVID-19 pandemic and will serve as a guide for other institutions in the region who will inadvertently need to provide these services as the demand increases.


2003 ◽  
Vol 19 (5) ◽  
pp. 1498-1504 ◽  
Author(s):  
M. Papagianni ◽  
M. Mattey ◽  
B. Kristiansen

1990 ◽  
Vol 55 (7) ◽  
pp. 1730-1740 ◽  
Author(s):  
Petr Ettler

Our philosophy of successful biotechnology transfer to industrial scale covers the comparison of complex sets of microbiological, analytical and bioengineering data from cultivations in various scales and different geometries of mixing with laboratory findings. In particular, the availability of nutrients to producing microorganism should be understood, therefore for quick scaling-up procedure of polyene antibiotics produced by Streptomyces noursei we recommend to use physiological marker as total dehydrogenase activity determination. The utility of scale-down tests for identification of process fluctuation, validation of new substrate batches and simultaneous control of inoculum quality was proved.


2020 ◽  
Vol 11 (SPL4) ◽  
pp. 2298-2303
Author(s):  
Sahar Elnajjar ◽  
Dixon Thomas ◽  
Osama Tabbara ◽  
Danial Baker

Reasons for choosing parenteral nutrition (PN) products depend on healthcare institutions internal and external factors. A decision to start, continue, scale-up, scale down, or stop compounding of PN involves multiple stakeholders. This study is an effort to analyze such factors and recommendations on decision-making. A strength, weakness, opportunities, threats (SWOT) analysis was prepared in consultation with major PN providers in the UAE and comparing to international best practices. Based on the SWOT analysis, a set of recommendations was prepared using the GRADE system (classification of quality of evidence and strength of recommendation). Feedback on the SWOT analysis and recommendations were collected from the PN providers. The SWOT analysis and recommendations address aspects of the choice of MCB-PN or compounded PN. It includes considerations on PN indication, availability of ingredients, types of patients, safety, and cost management with labor, automation, and outsourcing. It was received well. The SWOT analysis and recommendations are useful in decision-making in complex therapy like PN. It helps in institutional decisions on choices of MCB-PN or compounded PN. The impact of the recommendations is to be measured in the future.


BioTechniques ◽  
2021 ◽  
Vol 70 (2) ◽  
pp. 126-133
Author(s):  
Camila Hiromi Chiba ◽  
Marcos Camargo Knirsch ◽  
Adriano Rodrigues Azzoni ◽  
Antonio R Moreira ◽  
Marco Antonio Stephano

Biopharmaceutical products are of great importance in the treatment or prevention of many diseases and represent a growing share of the global pharmaceutical market. The usual technology for protein synthesis (cell-based expression) faces certain obstacles, especially with ‘difficult-to-express’ proteins. Cell-free protein synthesis (CFPS) can overcome the main bottlenecks of cell-based expression. This review aims to present recent advances in the production process of biologic products by CFPS. First, key aspects of CFPS systems are summarized. A description of several biologic products that have been successfully produced using the CFPS system is provided. Finally, the CFPS system's ability to scale up and scale down, its main limitations and its application for biologics production are discussed.


2021 ◽  
Author(s):  
Maurits Ertsen

<p>The call for this session mentions that “Earth system resilience critically depends on the nonlinear interplay of positive and negative feedbacks of biophysical and increasingly also socio-economic processes. These include dynamics in [many physical events], as well as the dynamics and perturbations associated with human activities.“ In this contribution, I would like to mobilize a few notions to discuss this issue.</p><p>A typical approach is to scale up human dimensions to Earth system model scales. Humans become aggregated into social structures, even societies, that change every year or so. I propose to scale down the Earth system to humans, both in terms of space and time. I think this offers exiting possibilities to study climate and earth systems in a different way, but also allows for answering the question how we could act today, tomorrow and next week in order to understand which long-term scenarios over decades are more likely to occur.</p><p>This would move us away from the view of the Earth as a single system or pattern to a perspective of Earth as an interconnected world of different non-human and human agencies. I would position this idea against the rather popular metaphor of the butterfly effect, “the sensitive dependence on initial conditions in which a small change in one state of a deterministic nonlinear system can result in large differences in a later state”. This may be too simple, as one butterfly will meet many other butterflies along the way. As such, the butterfly effect may be a specific example that claims a certain agency for smaller actors within the Earth System, but that builds its analysis on pattern replication through non-linear relations.</p><p>Our (perceived) knowledge of patterns colors our analysis of those patterns. We are all familiar with the metaphor of the men observing different parts of the elephant. The metaphor assumes that we know that what the men are examining is an elephant. However, once we do not know either what they are looking at, we need to start with them seeing different things. In the perspective that we know the elephant, the men are just short-sighted. In the more realistic setting that we cannot be certain about what the men observe, we are the ones that need to come up with a convincing way to analyze what is happening, has happened or may happen.</p><p>Much work in Earth system modelling model patterns in society, but do not explain how these patterns are the result of continuously performing agencies. The models are built to mimic the patterns that we observed. I propose to replace the patterns we use to explain the same patterns – whether they are power relations or gravity – with representations of the interacting agencies that together produce the Earth system that we think we observe. Gravity may be a nice explanation of the observed pattern that we do not glide away from the surface, but it remains just that. In our modelling efforts, we may apply the notion that gravity acts.</p>


Author(s):  
Srikanth Honavara Prasad ◽  
Daejong Kim

In recent years, gas foil bearings have gained increased attention due to potential applications in aerospace systems. Research and development efforts have been focused towards simplifying design and analysis methods or experimentally demonstrating stable bearing performance under various operating conditions. Many researchers have proposed design guidelines for parameters such as load capacity, stiffness, and damping etc., for extending the state of the art based on experimental data available in existing literature. The authors previously presented scaling laws for radial clearance and support structure stiffness of radial foil bearings. In that study, the criteria for selecting radial clearance and support structure stiffness for scale up or scale down of an existing bearing design was presented. In addition, the results from that paper showed that a hydrodynamic film could be sustained for large bearings (up to 300 mm diameter) demonstrating that the bearings would have adequate load capacity. However, the rotordynamic effects for the various bearing sizes were not considered in that study. This paper serves as an extension of the paper on scaling laws by the same authors. The subject of this paper is a four degree of freedom (4-DOF) rotordynamic analysis performed for turbomachinery systems that employ bearings designed using the scaling laws for radial clearance and support structure stiffness. Further, case studies to show feasibility of foil bearings for applications in Mega Watt range turbo blowers and turbo compressors is presented.


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