<p>Why the Product Life Cycle (PLC) model fails to explain in many cases the way</p><p>products (goods)/services’ sales evolve, and what problems can occur by using the</p><p>PLC as a tool for strategic decisions?</p>

Why the Product Life Cycle (PLC) model fails to explain in many cases the way products (goods)/services’ sales evolve, and what problems can occur by using the PLC as a tool for strategic decisions?

Thesis advisor: Jianmin Gao / Phosphatidylinositol-specific phospholipase C (PI-PLC) cleaves the substrate phosphatidylinositol through two steps: the first step occurs in the interface between lipid and solution, while the second step only takes place in water soluble environment. For interfacial catalysis, the enzyme should bind to the lipid surface first before engaging its substrate, therefore interfacial kinetics include both interfacial binding and an interfacial catalytic step. The Bacillus thuringiensis PI-PLC is activated by binding to zwitterionic surfaces; phosphatidylcholine (PC) and two tryptophan residues (Trp47 in the two-turn helix B and Trp242 in a disordered loop) at the rim of the barrel structure, in particular, are critical for this interaction. The helix B region in PI-PLC orients the side chains of Ile43 and Trp47 so that they form a hydrophobic protrusion from the protein surface that likely facilitates initial membrane binding. An earlier crystal structure of the dimeric W47A/W242A mutant, which is unable to bind to PC, showed that the helix B region was reorganized into an extended loop. Whether this conformational change occurred in the wild type PI-PLC was tested with a series of mutations targeting helix B residues and surrounding regions. Results strongly suggest that, while hydrophobic groups and presumably an intact helix B are critical for the initial binding of PI-PLC to membranes, disruption of helix B to allow enzyme dimerization is likely to play a role in the activated PI-PLC conformation. Besides the helix B residues, a number of hydrophobic residues along the rim of the <em>f</em>Ñ<em>f</em>Ò-barrel and close to both helix B and the active site were also altered to assess their contribution to membrane binding and kinetic activation. Results showed that Tyr86 and Tyr88, but not Tyr118, contribute to the protein binding to PC vesicles. These residues are capable of cation-<em>f</em>à interactions with the choline headgroup of the phospholipid PC. Although mammalian PLC<em>f</em>Ô1 is a complex multidomain protein, the catalytic domain resembles the bacterial PI-PLC enzymes. Little work has been done to characterize the extent to which this domain contributes to membrane binding. A mutated protein that removes the very anionic X/Y linker region that covers the active site was constructed. The interfacial binding and the corresponding enzyme activity of this mutant against WT were measured in both micelles and large unilamellar vesicles. The results showed at <em>f</em>ÝM protein concentration there was no large difference between the PLC<em>f</em>Ô1 and the deletion mutant in terms of vesicle binding. However, the deletion mutant showed much higher membrane binding affinity at nM concentrations. These results shed some light on the activation or inhibition role of the catalytic domain and pointed to a possible direction of future studies, for example examining specific mutant enzymes in the interfacial loop region. / Thesis (PhD) — Boston College, 2011. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Thesis advisor: Mary F. Roberts / Phosphatidylinositol-specific phospholipase C (PI-PLC) from B. thuringiensis is activated by phosphatidylcholine (PC) surfaces for both phosphatidylinositol (PI) cleavage to inositol 1,2-(cyclic)-phosphate (cIP) and subsequent hydrolysis of cIP to inositol-1-phosphate. These enzyme kinetics strongly suggest that this PI-PLC has two discrete binding sites for phospholipids - the active site binding PI (or substrate competitors) and an activator site specific for PC. However, it is difficult to determine the orientation and conformation of peripheral membrane proteins when docked to target membranes, let alone where sites for these might be on the protein. In this thesis, various biophysical techniques were applied to this bacterial PI-PLC to obtain structural information in the absence and presence of membranes to characterize specific conformational changes that occur when the protein binds to activating membranes. The crystal structures of an interfacially impaired double mutant of PI-PLC, W47A/W242A, was solved and showed the protein as a homodimer. The major interactions came from four clustered surface tyrosine residues from each monomer. This structure suggested the possibility of PI-PLC dimerization on membrane surfaces as part of the mechanism for interfacial activation. Mutations of these tyrosines showed a loss of activity and membrane binding. Crystal structures of these mutant proteins showed no significant change in the proteins, consistent with either disruption of a dimerization interface of a specific PC binding motif. FRET was used to try and monitor oligomerization of PI-PLC, derivatized on a cysteine introduced at residue 280 (W280C) with either a donor or acceptor fluorophore, on vesicle surfaces. The results suggested some specific aggregation could occur on very PC-rich surfaces but not on phospholipid vesicles with at least 50 mol% anionic phospholipids, strongly suggesting that a stable dimer was not forming when the enzyme was bound to vesicles mimicking conditions where enzyme specific activity is high. If dimerization occurs on surfaces, it must be transient. To examine which portions of the PI-PLC are interacting with membrane and to further explore if there is any evidence for PI-PLC dimerization on membrane surface, deuterium exchange coupled by mass spectrometry experiments were carried out with wild type PI-PLC, W47A/W242A and a covalent dimer formed from W242C that is more active than wild type enzyme. Results showed (i) a stable short helix B (containing an exposed tryptophan thought to insert into membranes) in wild type PI-PLC and its complete destabilization in W47A/W242C, (ii) a flexible surface loop (containing another tryptophan thought to partition into the membrane) that became protected when the protein was bound to vesicles, and (iii) reduced deuterium exchange for the peptide containing the tyrosines that either mediate transient dimerization or form a PC binding site.. These observations modify how we envision the protein anchoring to substrate-containing membranes. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

This report discusses developing a software log tool for analysis of industrial processes. The target was to develop software that can help electro Engineers for monitor and fault finding in industrial processes. The tool is called PLS (Process log server), and is developed in Visual Studio.NET Framework 2005. PLS works as a client with Beijer Electronics OPC Server. The program is able to read data from PLC (Programmable Logic Controller), trough the OPC Server. PLS connects to all kind of controllers that is supported by the Beijer Electronics OPC Server. Signal data is stored in a database for later analysis. Chosen signals data can easily be exported into a text file. The text file is adopted for import to MS Office Excel. User manual [UM-07] is written as a separate document. The software acted stable through the function test. The final product becomes a first-rate tool that is simple to use. As an advantage, the software can be developed with more functions in the future.

I was assigned to the thesis as part of a project GMA AB (Ground Machinery Applications AB) is running. The project aims to develop a new method for injection of drilled holes in rock walls. Currently, the injections usually involve cement but the basic idea of the project is to replace cement with a supplement called Silica sol. Silica sol is known as a gelling liquid. The gel time is controlled by a mixing of saline. Depending on the amount saline that gets mixed in, the gel time varies. By controlling the ratio of Silica Sol and saline during an injection, you can make all the Silica sol and saline harden simultaneously and that consequently affect how deep into the rock wall the gelling fluid ingress. To the project GMA bought a pump station which was previously used in a similar project. The purpose was to review the pumping stations components and if possible, use these to meet the objective.  During the project two proposals of the pumping system structure were considered.  The proposal that was considered to be the best were chosen based on practical criteria. The existing pump station components were supplemented with new components and a pumping system was built up by the developed proposal. The pumping stations associated electrical box was rebuilt to meet the requirements of the system and a Mitsubishi PLC system was implemented and drawings of the electrical components were made. Then a program to control the pump station manually was created in order to verify that the components were connected properly. Then a program containing a PID controller was created in order control the ratio of silica sol and saline and also to maintain the required pressure in the system. The pump station was tested against a water tank and two methods for frequency based regulation setting were used to set the PID controller parameters. Part of the goal which unfortunately did not get realized due to lack of time was to test the pump station against a pipe that was built to simulate a real drilled hole. Therefore the PID parameter setting did not get optimized for a proper injection with silica sol and saline. Based on the results and all the progress, this report will be a good base to start from when someone chooses to proceed with this project.

In order to reduce the price for, and improve the performance of automatic control systems for magnetization of synchronus generators, the possibilities of using a PC based software PLC system, Programmable Logic Controller, has been investigated. The result is a system based on the CoDeSys software PLC with runtime environment from 3S-Software, communicating with external units via Modbus fieldbus. System price is reduced from €5000 to €2000 and system processing speed is reduced from 10 ms for a Siemens S7 PLC to 4 ms with the CoDeSys PLC system though unsolved problems with runtime seizure caused by improper settings in the PC BIOS.

Det här arbetet handlar om sågreglering i syfte att förbättra precisionen i sågningen. I dagens sågverk är utrustningen modern men sättet att bestämma korrigeringsvärden för bandsågar är omodernt. Arbetet innehåller analys, programmering samt kalkylering. En del i arbetet består av att finna störningar i sågprocessen och eliminera störningarna med hjälp av sågkorrigering. Mätningen sker med en noggrannheten på en tiondels millimeter. En algoritm som korrigerar sågarna för bästa möjliga resultat har implementerats i PLC och Excel. Denna algoritm ger ett snabbt svar för korrigeringsvärdet.

<p>This degree project has been carried out in cooperation with Gedevelop in Helsingborg.</p><p>Gedevelop has developed a camera that can calculate the weight of a liquid glass mass.</p><p>Because of the density and viscosity changes in the glass, the weight information is</p><p>sometimes incorrect given. Glass industry is today addressing the problem by an operator</p><p>performing a manual weighing of a few bottles which, in turn, calibrates the camera system.</p><p>The project aimed to develop an automated system to control the weighing of glass bottles for</p><p>glass industries. This system must be so flexible that it can be easily mounted on plants with</p><p>different production equipment around the world.</p><p>The project includes design and construction of equipment that meets the requirements</p><p>formulated together with Gedevelop. Work has been done both in Halmstad and Helsingborg</p><p>and has included both calculations and review of the theory to understand the forces that</p><p>influence the design of different construction parts. A prototype was produced that meets the</p><p>operating requirements for the design and can be used in testing features. However, the design</p><p>does not meet the requirements to be set up at a production line because it does not pass the</p><p>temperature appearing in glass industry. This can easily be remedied by further modification</p><p>of the design in terms of protection of stainless steel.</p>

This degree project has been carried out in cooperation with Gedevelop in Helsingborg. Gedevelop has developed a camera that can calculate the weight of a liquid glass mass. Because of the density and viscosity changes in the glass, the weight information is sometimes incorrect given. Glass industry is today addressing the problem by an operator performing a manual weighing of a few bottles which, in turn, calibrates the camera system. The project aimed to develop an automated system to control the weighing of glass bottles for glass industries. This system must be so flexible that it can be easily mounted on plants with different production equipment around the world. The project includes design and construction of equipment that meets the requirements formulated together with Gedevelop. Work has been done both in Halmstad and Helsingborg and has included both calculations and review of the theory to understand the forces that influence the design of different construction parts. A prototype was produced that meets the operating requirements for the design and can be used in testing features. However, the design does not meet the requirements to be set up at a production line because it does not pass the temperature appearing in glass industry. This can easily be remedied by further modification of the design in terms of protection of stainless steel.