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Conceição do Almeida, Brazil

Bergmans R.H.,VSL Dutch Metrology Institute | Nieuwenkamp H.J.,VSL Dutch Metrology Institute | Kok G.J.P.,VSL Dutch Metrology Institute | Blobel G.,Physikalisch - Technische Bundesanstalt | And 6 more authors.
Measurement Science and Technology | Year: 2015

A comparison of topography measurements of aspherical surfaces was carried out by European metrology institutes, other research institutes and a company as part of an European metrology research project. In this paper the results of this comparison are presented. Two artefacts were circulated, a small polymer coated aspherical lens with a clear aperture of about 12 mm, and a large conical convex lens with a clear aperture of 300 mm developed for the ESO Very Large Telescope. The participating laboratories were allowed to follow their own measurement strategies. Both tactile and optical measuring instruments were used, as well as single point and imaging techniques. The measured data were compared with respect to the root-mean-square (RMS), peak-to-valley and Zernike polynomial representations of the measured deviations from the nominal shape. The comparison shows for five out of eight measuring instruments/methods a very good agreement of the measured topographies within 14 nm (RMS). © 2015 IOP Publishing Ltd.

Gallego I.,University of Mondragon | Oliveira J.F.G.,IPT | Barrenetxea D.,Scoop Inc | Takahashi M.,Nissin Machine Works Ltd. | And 4 more authors.
CIRP Annals - Manufacturing Technology | Year: 2012

This paper reviews the history of centerless grinding and its contribution to industry. It summarizes the evolution of centerless grinding theory including advanced modeling and simulation. Then, it discusses the design of main elements of a centerless grinding machine such as spindles, bed, guideways and positioning system, and provides design guidelines for future machines. The paper presents the state-of-the-art centerless grinding technologies: advanced machines, advanced process monitoring and the latest developments in grinding wheels. Finally, in conclusion, future trends and research work in centerless grinding technology are discussed. © 2012 CIRP.

News Article
Site: phys.org

Industry 4.0 requires comprehensive data collection in order to control highly automated process sequences in complex production environments. One example is the cultivation of living cells. But digitalizing and networking biotech production equipment is a huge challenge: relevant standards have yet to be established, and biology has a dynamic all its own. Using fully automated equipment for producing stem cells, Fraunhofer researchers have managed to adjust the process control to cell growth – delivering an adaptive system that is suitable for use in a number of sectors. The term industry 4.0 is generally associated with the manufacturing of cars, machinery or industrial goods. But, as the partners (see box) in the StemCellFactory collaborative project show, the comprehensive networking of machines and products is also making headway in biotechnology. This is a particular challenge, because this field deals not with solid components but with living objects that – unlike screws or gears – change and multiply. Networked process control needs to take this into account and be able to adjust the process accordingly in real time. The StemCellFactory project partners have set up a fully automated production line for culturing stem cells, which can develop into any kind of cell found in the body; experts call them induced pluripotent stem cells (iPS cells). Researchers from the Fraunhofer Institute for Production Technology IPT will be presenting the production line at the Hannover Messe Preview on January 27 and at the Hannover Messe (Hall 17, Booth C18 and Hall 2, Booth C16) from April 25 to 29. Medical expertise was provided by experts from the university clinics in Bonn and Aachen, among others. iPS cells such as these are necessary in the development of medications used in personalized medicine. They are obtained from adult body cells such as human skin or blood cells. First, a doctor takes cells from a patient. Next, these cells are reprogrammed to become iPS cells by adding certain substances. This causes the cells to revert to an embryonic state, from which they can theoretically differentiate into any cell type – even heart or nerve cells, which, owing to the risk to the patient, cannot be obtained by means of a biopsy. The pharmaceutical industry uses these cells for medical tests: since they contain the patient's own genetic information, the cells are very useful for determining which medications will be effective. To date, iPS cells are grown by lab specialists in a painstaking, time-consuming process. The number and quality of iPS cells that can be cultured depend entirely on how experienced the lab technician is. This is why the project aimed to develop fully automated, modular equipment that achieves both a high throughput and a consistently high quality of stem cells. The IPT experts were given the task of developing both the equipment and its control mechanisms. They faced a number of challenges, the first being how to network the various biotech devices – liquid handling robot, a microscope, an incubator, and the automatic magazine for storing cells and containers – in a way that permitted the use of process-control technology in the first place. "Despite the industry's efforts to establish uniform interfaces for lab automation equipment, there is as yet no international standard for networking the devices used," says IPT developer Michael Kulik. "That means plug and play is not an option, so we first had to develop a standard of our own before we could integrate everything." This approach achieved a very high degree of networking in order to allow the process-control technology and the lab equipment to exchange information. That in turn was the prerequisite for the equipment to adjust extremely flexibly to the biological processes at work. Cell growth is the decisive factor. As the cells grow in the cell culture vessels, they divide again and again. To ensure conditions don't get too cramped for the cells, from time to time the pipette feeder robot has to distribute them among a larger number of fresh, empty cell culture vessels. To this end, the microscope developed at the IPT regularly examines the growth density inside the cell culture vessels. Once a critical density is reached, the microscope sends out an instruction to rehouse the cells. "This is an example of the product, in this case the growing stem cells, determining how the overall process unfolds," says Kulik. In other words: production has the capability to adjust itself to the present situation. A user interface makes it easy to control each device included in the equipment. If the user needs to alter or add to the equipment's process steps, there are pre-programmed blocks of instructions that they can simply drag into or out of the control menu. Staff can choose whether to operate the equipment in fully automated or manual mode. The technology developed as part of the StemCellFactory project can also be applied in other situations, for instance in tissue engineering and the production of tissue models. It would also be possible to use it to manufacture gears, screws, engines, etc. in a fully automated way. The software is scalable, making it suitable for small and large production facilities alike. Since the programming is extremely flexible, the process-control technology can be transferred to any other production setup in need of adaptive control on the basis of current measurement data. During the Hannover Messe, visitors will be treated to a live demonstration of how the StemCellFactory is controlled remotely, specifically from Bonn. Explore further: Production of iPS cells: Discovery of the fifth element

Banerjee R.,Bharat Technology | Roy D.,IPT | Banerjee M.,IPT
Der Pharma Chemica | Year: 2016

Six substituted N-aryl,5-substituted phenyl 1,3,4-thiadiazole(7a-f) were synthesized by the reaction of different substituted benzaldehyde with different substituted 5-phenyl 1,3,4-thiadiazole 2-amino in the presence of sulphuric acid in refluxing methanol. The newly synthesized compounds were characterized by spectroscopic methods. Further, the synthesized compounds were screened for antibacterial and antifungal activity by standard method. Results of the activities reveal that some compounds exhibited moderate to good antimicrobial activity.

Vidyavathi M.,IPT | Papishetty S.,IPT
Trends in Biomaterials and Artificial Organs | Year: 2013

Present study aims to prepare and evaluate niacin microspheres with a biopolymer. Chitosan was selected as biopolymer due to its biodegradable nature, fat binding capacity and anti-ulcer activity. Niacin-chitosan microspheres were prepared by chemical de-naturation method. Nearly spherical, free flowing microspheres having an entrapment efficiency of 70.42 were obtained. The effect of polymer-drug ratio, calcium chloride concentration, cross-linking agent concentration and stirring speed were evaluated with respect to entrapment efficiency, in vitro drug release behavior and particle size. FT-IR and DSC analysis confirmed the absence of drug-polymer interaction. The in vitro release profile could be altered significantly by changing various processing and formulation parameters to give a controlled release of drug from the microspheres. The percentage yield was 83%, particle size range was 54 to 94 μm. The drug release was controlled for 10 h. The in vitro release profiles from optimized formulations were applied on various kinetic models. The best fit with the highest correlation coefficient was observed in Higuchi model, indicating diffusion controlled principle. The in vitro release profiles of optimized formulation was studied and compared with commercially available niacin extended release formulation.

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