Growing consumer awareness of the health benefits associated with fruits and vegetables and demand for easy to prepare products has prompted the development of a wide variety of minimally processed fruits and vegetables. Minimally processed fruits and vegetables are often peeled, cut, or diced which compromise the produces’ natural protective barriers, exposing a nutrient rich medium and providing an ideal environment for the growth of microorganisms, including foodborne pathogens. The germination conditions of sprout vegetables consisting of relatively high temperatures and humidity, low light and abundance of nutrients are also conducive to the proliferation of foodborne pathogens. Recent outbreaks and recalls indicate additional measures are needed to improve food safety and maintain the integrity of the food industry. The objective of this research was to evaluate the efficacy of Lactic Acid Bacteria (LAB) against E. coli O157:H7, L. monocytogenes, and Salmonella spp. on apple slices and alfalfa sprouts and it’s influence on product quality. Apple slices inoculated with E. coli O157:H7, L. monocytogenes, and Salmonella spp. (each at 104 CFU/g) were treated with Lb. plantarum alone and in combination with Pediococcus acidophilus and P. pentosaceus (LPP) (107 CFU/g) while alfalfa seeds were inoculated with L. monocytogenes and Salmonella spp. (each at 101 CFU/g and 103 CFU/g) and treated with LPP (107 CFU/g). The growth of the microorganisms on the apple slices was assessed during five and seven days of storage at 4◦C and 20◦C, respectively. Growth on alfalfa seeds was reported during five days of sprouting at 20◦C. Populations of LAB were maintained between 7.0 log CFU/g and 8.0 log CFU/g throughout storage and sprouting on the sliced apples and alfalfa seeds, respectively. Although LAB had no significant effect on pathogen populations on apple slices during storage at 4°C (p > 0.05), populations were significantly different at 20°C (p < 0.05). Populations of L. monocytogenes in the presence of Lb. plantarum and LPP were 1.84 log CFU/g and 2.84 log CFU/g less than the controls after five days of storage at 20°C (p < 0.05). Populations of E. coli O157:H7 in the presence of Lb. plantarum and LPP were 1.83 log CFU/g and 1.86 log CFU/g less than the control after one and three days of storage, respectively. Finally, populations of Salmonella spp. were 0.86 log CFU/g less than populations in the absence of LPP after three days of storage. LPP had a significant effect on the growth of L. monocytogenes and Salmonella spp. on alfalfa seeds (p < 0.05). After five days of sprouting, populations of L. monocytogenes at an initial concentration of 101 CFU/g and 103 CFU/g on seeds treated with LPP were approximately 4.5 log CFU/g and 1.0 log CFU/g less than the untreated seeds, respectively. Populations of Salmonella spp. at an initial concentration of 101 CFU/g and 103 CFU/g were 1.0 log CFU/g less than the control. Overall, on apple slices the combination of Lb. plantarum with P. acidophilum and P. pentosaceus demonstrated greater efficacy than Lb. plantarum alone and reduction of L. monocytogenes by Lb. plantarum and LPP was greater than Salmonella spp. and E. coli O157:H7 on apple slices and alfalfa seeds, alike. LAB had a minimal effect on the quality of the apple slices and alfalfa seeds. LAB could be an effective strategy in reducing pathogen populations at abusive temperatures and germination conditions without influencing the quality of minimally processed fruit and vegetables.

This thesis explores the factors contributing to successful collaboration within the Quadruple and Quintuple Helix frameworks, with a specific focus on the active involvement of students as stakeholders. A qualitative research approach was adopted, utilising interviews, questionnaires, and action research documented in a diary form, to gather data. The study examines the Creative LAB, an innovation lab initiated by students in the Innovation and Design master’s program at Mälardalens University, as a base for the collaborations with which the data is inquired from. The research employs the Quadruple and Quintuple Helix models as theoretical frameworks to understand collaboration dynamics. Phenomenographic analysis was used to categorise and analyse the experiences of collaboration. The interviews and questionnaires, both addressing the same topic, were transcribed, and subjected to systematic extraction and analysis. The findings are presented in the form of categories, supported by direct quotations and perspectives from the respondents. The research diary served as a reflective tool throughout the thesis, documenting and analysing the obtained results and the work conducted within the Creative LAB. It provided valuable insights into the collaboration dynamics, success factors, and the role of students as active stakeholders in the Quadruple and Quintuple Helix models. By capturing observations and personal reflections, the diary contributed to a deeper understanding of the research findings and enhanced the overall validity of the study. One of the projects, WellBot, is also presented as a case study. In summary, this thesis provides insights into the key success factors for collaboration within the Quadruple and Quintuple Helix frameworks, while also highlighting the significant role of students as active stakeholders. The results shed light on the perceptions and experiences of the participants, offering valuable implications for fostering effective collaboration in the context of academia, industry, and society. In the end, success-factors identified within the study is presented, as well as a questionnaire to identify perceptions on potential collaborations.

Information and communication technologies are being implemented more than ever in the power industry in order to make smarter power grids, termed as cyber-physical power systems (CPPSs). Along with the privileges of such modern power networks like reducing the total operation cost for end-use customers, they may be negatively affected by cyberattacks, above all false data injection (FDI) attacks as they are easier to be performed. As a case in point, an adversary can detour security systems, penetrate into the cyber layer of a typical CPPS, and manipulate the information, finally leading to security threats. Although prevention and detection mechanisms are significant tools to be utilized by power system operators to improve the reliability of such systems against cyberattacks, they cannot ensure the security of power grids since some FDI attacks might be designed to bypass the detection stage. Hence, a more powerful tool will be required, which is called remedial action scheme (RAS), to be implemented by power system operators to recover the targeted power grid in a timely manner. Toward this end, different RAS frameworks are presented in this dissertation in transmission, distribution, and microgrid levels to highlight the effectiveness of such reaction mechanisms in case of cyber threats targeting modern power systems. In the transmission level, optimal power flow (OPF) integrated with thyristor controlled series capacitor (TCSC) have been utilized to design a RAS to mitigate the negative impacts of FDI attacks, resulting in system congestion or power outages. In the distribution level, system operators take advantage of static VAR compensator (SVC) through solving a customized version of distribution feeder reconfiguration (DFR) problem to mitigate voltage violations in the form of overvoltages and undervolatges, caused by FDI cyberattacks. In light of the fact that some FDI attacks bypass the employed detection methods, it is crucial to prepare in advance for such scenarios. Hence, in this dissertation, a real-world framework is also proposed for mitigating false data injection (FDI) attacks targeting a lab-scale wind/PV microgrid and resulting in power shortage. The proposed RAS is developed as a hardware-in-the-loop (HIL) testbed within the cyber-physical structure of the smart microgrid. Finally, as a prerequisite of the proposed intelligent RAS, which is able to be used on different levels of a CPPS, power system operator is being in attacker’s shoe to scrutinize different scenarios of cyberattacks to make an initial archive set. The design of such mechanisms incorporates long-short-term memory (LSTM) cells into a deep recurrent neural network (DRNN) for the processing of archived data, termed intelligent archive framework (IAF), identifying the proper reaction mechanisms for different FDI cyberattacks. To react to cyberattacks for which similar pre-investigated remedial measures were not saved in the IAF, a power flow analysis is considered to a) examine the interdependency between transmission and distribution sectors and b) generate appropriate RASs in real time.

No description available.

The application of GPS probes in traffic management is growing rapidly as the required data collection infrastructure is increasingly in place in urban areas with significant number of mobile sensors moving around covering expansive areas of the road network. Most travelers carry with them at least one device with a built-in GPS receiver. Furthermore, vehicles are becoming more and more location aware. Currently, systems that collect floating car data are designed to transmit the data in a limited form and relatively infrequently due to the cost of data transmission. That means the reported locations of vehicles are far apart in time and space. In order to extract traffic information from the data, it first needs to be matched to the underlying digital road network. Matching such sparse data to the network, especially in dense urban, area is challenging. This thesis introduces a map-matching and path inference algorithm for sparse GPS probes in urban networks. The method is utilized in a case study in Stockholm and showed robustness and high accuracy compared to a number of other methods in the literature. The method is used to process floating car data from 1500 taxis in Stockholm City. The taxi data had been ignored because of its low frequency and minimal information. The proposed method showed that the data can be processed and transformed into information that is suitable for traffic studies. The thesis implemented the main components of an experimental ITS laboratory, called iMobility Lab. It is designed to explore GPS and other emerging traffic and traffic-related data for traffic monitoring and control. / <p>QC 20121107</p>

Borehole heat exchangers are widely used in heat pumps of residential buildings and industrialsystems. It is known as one of the most energy ecient technologies which provides heatingand cooling by using sustainable geothermal energy. The life time of borehole heat exchangerslasts more than 50 years which is longer than combustion boilers. Therefore, designing abore eld with accurate sizing is important for its future applications. Due to the large volumeof the ground, the transient heat transfer process of the bore eld lasts for a long time span. Because of this, only a few of the heat transfer models for borehole ground heat exchangersare validated by experiments. Besides, experimental validation in a real scale borehole can bedicult because of the uncertainty of the composition and thermal properties of the ground. A solution to faster experimental validation is to scale down the size of the borehole andground. This report presents the construction process of a lab-scale model simulating a 4x4 bore eldof 300 m depth vertical boreholes. The process of experimental construction is describedin detail, including ground set up, conductivity test, construction of hydraulic system anddata acquisition system. The pressure drop of hydraulics system is around 2.8 bar under the a flow rate of 200 ml/min and corresponding pump speed is around 2900 to 3100 rpm. The property of the sand has been investigated through a series of conductivity tests, which shows an average thermal conductivity of 1.75 W / (m • K) and average thermal diffusivity of 8.14x10-7 m2/s. Numerical simulation (via COMSOL) is carried out for preliminary validation. Comparison of experimental and simulation results shows discrepancies and one possible reason can be: the actual heat injection rate in experiment is lower than simulation due to heat losses of hydraulic system; uncertainty of ground (saturated sand) conductivity and thermal diffusivity. / Borrhålsvärmeväxlare används ofta i värmepumpar i bostadshus och industrisystem. Det är känt som en av de mest energieffektiva teknikerna som tillhandahåller värme och kyla genom att använda hållbar geotermisk energi. Livslängden för borrhålsvärmeväxlare varar mer än 50 år vilket är längre än förbränningspannor. Därför är det viktigt att utforma ett borrfalt med exakt dimensionering för dess framtida tillämpningar. På grund av den stora markvolymen varar den transienta värmeöverforingsprocessen i borrfältet under lång tid. På grund av detta är endast ett fåtal av värmeöverföringsmodellerna för borrhålsjordvärmeväxlare validerade genom experiment. Dessutom kan experimentell validering i ett borrhål i verklig skala vara svårt på grund av osäkerheten i markens sammansättning och termiska egenskaper. En lösning för snabbare experimentell validering är att skala ner storleken på borrhålet och marken. Denna rapport presenterar konstruktionsprocessen av en modell i labbskala som simulerar ett 4x4-borrfält med 300 m djupa vertikala borrhål. Processen for experimentell konstruktion beskrivs i detalj, inklusive markuppställning, konduktivitetstest, konstruktion av hydraulsystem och datainsamlingssystem. Tryckfallet for hydrauliksystemet är cirka 2,8 bar under en flödeshastighet pa 200 ml/min och motsvarande pumphastighet är runt 2900 till 3100 rpm. Sandens egenskaper har undersökts genom en serie konduktivitetstester, som visar en genomsnittlig värmeledningsformåga pa 1,75 W/(m • K) och en genomsnittlig termisk dffusivitet på 8.14x10 -7 m2/s.  Numerisk simulering (via COMSOL) utförs för preliminär validering. Jämförelse av experimentella och simuleringsresultat visar avvikelser och en möjlig orsak kan vara: den faktiska värmeinsprutningshastigheten i experimentet är lägre än simulering på grund av värmeförluster i hydraulsystemet; osäkerhet i markens (mättad sand) konduktivitet och termisk diffusivitet.

Laboratories within quality control are very complicated to schedule due to the high product mix and diversified products tested with many different analysts and instruments. Thus, it requires a flexible planning system to change and improve the overall lab performance and increase efficiency. This thesis is a case study in collaboration with Fresenius Kabi AB and the quality control (QC) department in Uppsala. The QC department has an inflow of batches from the production department as well as from internal customers. Internal customers usually send batches that are part of stability studies or projects. These stability batches arrive at the QC department within irregular intervals and sometimes tightly adjacent, making the QC planning more complex, creating backlogs. Hence, the question in the study is formulated: ● How to improve a planning system and workflow in a quality control department? The current condition of batch inflow and how the planning system is managed today have to be understood to answer the question. Hence, the following sub-questions will be answered: ○ How is the current planning system at the quality control structured? ○ How is the inflow of stability batches at the department made more even andpredictable? This study aims to accomplish a practical planning system to prevent WIP, bottlenecks, and backlogs. The thesis is based on a qualitative method involving an inductive approach. The data collected mainly includes data from incoming batches, interviews, and literature studiesto gain multiple perspectives on the covered area. The study results showed that the internal customers were not satisfied with the current delivery times of QC. The common patterns identified are that internal customers want more contact and cooperation with the QC department. Furthermore, the result shows that the QC can handle the batches that arrive, but the planning system is not good enough. The proposed improvements to the current planning  system are mainly to change it to a longer-term planning system and introduce a standard log or planning system between the internal departments. Also, QC should reorganize the lab and schedule based on common analysis to accomplish a higher efficiency of the scheduling. Further recommendations include more transparency and precise planning between departments to improve the inflow of the stability batches. / Quality Control (QC) laboratorium är svåra att planera detta på grund den höga mängden och variationen av produkter. Det kräver således ett flexibelt planeringssystem för att förändra och förbättra prestandan och öka effektiviteten i laboratorier. Detta examensarbete är en fallstudie i samarbete med Fresenius Kabi AB och deras kvalitetsavdelningen i Uppsala. QC avdelningen har ett inflöde av batcher från produktionsavdelningen samt från de interna kunder. De interna kunderna skickar vanligtvis batcher som ingår i stabilitetsstudier eller projekt. Dessa stabilitets batchar inkommer till QC inom icke bestämda tidpunkter och ibland tätt inpå varandra, vilket försvårar planeringen inom QC vilket in sin tur skapar backloggar. Därav är frågeställningen i studien formulerad: ● Hur kan ett planeringssystem och arbetsflöde i ett kvalitetskontroll laboratoriumförbättras? För att kunna besvara denna frågeställning bör det aktuella planeringssystemet i avdelningen att undersökas. Därav kommer även dessa delfrågor att besvaras för att i denna studie: ● Hur är det nuvarande planeringssystemet strukturerat? ● Hur kan inflödet av stabilitets studier på avdelningen jämnas ut och bli mer förutsägbara? Syftet med denna studie är därav att effektivisera det nuvarande planeringssystem för att förhindra WIP, flaskhalsar och backlogs i QC avdelningen. Examensarbetet bygger på en kvalitativ metod med en induktiv forskningsansats. Den insamlade datan främst inkluderar data från inkommande batcher, intervjuer samt litteraturstudie för att få flera perspektiv av det undersökta ämnesområdet. Studiens resultat visade att samtliga interna kunder inte är nöjda med de nuvarande leveranstider som QC har. De gemensamma mönster som identifierats är att de interna kunderna önskar mer kontakt och samarbete med QC avdelningen. Vidare visar resultatet att QC bör ha kapaciteten som krävs för att kunna hanterade batcher som inkommer men att planeringen inte är tillräckligt bra. De förbättringsförslag som föreslås till det nuvarande planeringssystemet är främst att utveckla en mer långsiktig planering samt införa en gemensam logg. QC avdelningen på Fresenius Kabi bör även se över sin organisering och dela in grupper baserat på analyser och inte utrustning. Vidare rekommendationer inkluderar mer transparent och tydlig planering mellan avdelningarna.

Since laboratory tests influence as much as 70% of the medical decisions, errors throughout the blood sampling process may jeopardize the safety of the patient. Research has shown that the pre-analytical phase of the blood sampling process is where the most errors occur. Moreover, this phase is said to be the most influential part of the total testing process, due to maximal involvement of humans. In this study, the pre-analytical errors in the blood sample handling process and their causes were investigated. Therefore, a literature study was performed, and first-hand data was collected through interviews. A total of 8 interviews was conducted in Sweden, Belgium, and the Netherlands. From these interviews, qualitative data was collected and analysed with a thematic approach. The 5 themes that were obtained are: nurse vs. lab technician, sample identification, logistics, location dependency of sample quality, and hospital management. Each theme included multiple observations and conclusions. One specific observation was a lack of communication and knowledge management amongst nurses and lab technicians. To minimize this gap between nurse and lab technician from a knowledge transfer perspective, a conceptual framework was constructed. This framework can be used both from an academic and practical point of view. This research has both academic and practical implications. Within the academic perspective, empirical data is gathered among hospitals in three different countries, which is compared to data found in academic literature. Moreover, with the analysis of the empirics gathered in this study and the framework that is proposed, a contribution is made to knowledge management within hospitals. From a practical perspective, a contribution is made in helping to minimise the pre-analytical errors in their blood sampling process, while giving the hospital a better understanding of the lack of communication and knowledge management amongst their key employees. By strengthening the communication and knowledge transfer, errors can be avoided. This would not only benefit the speed and accuracy of the diagnose process, but also benefit the nurses and lab technicians in workload. / Eftersom laboratorietester påverkar så mycket som 70 % av de medicinska besluten kan fel i blodprovstagningen äventyra patientsäkerheten. Forskning visar att det är i den föranalytiska fasen av blodprovstagningsprocessen som de flesta felen uppstår. Dessutom sägs denna fas vara den mest inflytelserika delen av den totala provtagningsprocessen, på grund av den höga graden av människors inblandning. Denna studie undersökte de föranalytiska felen i blodprovshanteringen och deras orsaker. En litteraturstudien genomfördes, och förstahandsuppgifter samlades in genom intervjuer. Totalt åtta intervjuer genomfördes i Sverige, Belgien och Nederländerna. Från dessa intervjuer samlades kvalitativa data in och analyserades med en tematisk ansats. De fem teman som erhölls var: sjuksköterska jämte laboratorietekniker, providentifiering, logistik, platsberoende provkvalitet och sjukhusledning. Varje tema innehöll flera observationer och slutsatser. En specifik observation var bristen på kommunikation och kunskapshantering mellan sjuksköterskor och laboratorietekniker. För att minimera denna klyfta mellan sjuksköterska och laboratorietekniker ur ett kunskapsöverföringsperspektiv konstruerades en konceptuell ram. Denna ram kan användas både ur akademisk och praktisk synvinkel. Denna forskning har både akademiska och praktiska konsekvenser. Utifrån det akademiska perspektivet samlades empiriska data in bland sjukhus i tre olika länder, som jämförs med data i den existerande litteraturen. Med analysen av den empiri som samlats in i den här studien och det ramverk som föreslås ges dessutom ett bidrag till kunskapshantering inom sjukhus. Ur ett praktiskt perspektiv bidrar detta till att minimera de föranalytiska felen i blodprovstagningsprocessen, samtidigt som sjukhuset får en bättre förståelse för bristen på kommunikation och kunskapshantering bland sina nyckelpersoner. Genom att stärka kommunikationen och kunskapsöverföringen kan fel undvikas. Detta skulle inte bara gynna diagnostikprocessens snabbhet och noggrannhet, utan även avlasta sjuksköterskorna och laboratorieteknikernas arbetsbörda.

In both, cell secretome analysis and bacteria evolution, controlled handling of particles with a few to sub-micrometers in size and media exchange are inevitable in order to investigate body fluid’s proteins or change the surrounding culture conditions for pivoted evolution. Typically, nanofiltration and ultra-centrifugation are employed which can lead to cell damage, need large sample volumes and have a high sample loss. Using contactless and label-free acoustic cell manipulation, disadvantages of other magnetic, dielectric or hydrodynamic methods can be avoided. Here, a novel design using acoustic forces for small particle trapping and media exchange is thoroughly numerically investigated including first- and second-order acoustic effects. The device comprises parallel aligned medium and air channels separated by a thin wall. Particle trapping occurs at this thin wall. The medium channel dimensions (height and width) and thin wall thickness are optimized with respect to trapping forces. Thinnest walls are preferable and an aspect ratio of 0.8. First preliminary experimental variation with polystyrene particles showed good agreement with the simulations. Thereby the particle trapping efficiency is evaluated under quiescent flow conditions. For particle trapping, a device with a channel height of 290μm and an aspect ratio of 0.7 is superior which supports the numerical results. Finally, medium exchange of E. coli bacteria is demonstrated with best results for a device with a channel height of 450μm and an aspect ratio of 0.8 showing that 13.4% of the initial bacteria were released after medium exchange which can be used for further processing.

<p>Achieving control over the construction and operation of microfabricated label-free DNA biosensors would be a big leap in the quest for highly reliable clinical laboratory tests. Reliable outcomes of critical medical tests mean less need for repetitions and earlier isolation of outbreaks. Nanotechnology has lent itself well to this purpose, with a plethora of work that attempt to produce highly sensitive nano-biosensors for detection of DNA strands. The problem of achieving a repeatable outcome is crude at best. Additionally, the mechanism of sensing in label-free Field-Effect based DNA sensors is still a matter of dispute. Simulation of the sensors using physical models can shed light into these mechanisms and help answer this question. Computational calculations can also allow designers to assess the importance of several parameters involved in the fabrication.</p> <p>In this thesis, the problem of modeling FET-based DNA hybridization sensors (named BioFET) is approached. Using the Finite-Element Method, a scalable model for the BioFET is produced and solved in 3D. The results are compared to an earlier work and we find that higher dimension physical modeling is essential for more realistic results. Additionally, we present a model for the impedance of the BioFET which allows the calculation of parasitic components that can contaminate the impedance measurements.</p> <p>The issue of variations in the sensed signal from the BioFET is addressed by performing hybrid Finite-Element/Monte Carlo simulations on the conformation of single-stranded DNA. From electrostatic considerations alone, it is concluded that the change of conformation upon hybridization is a main contributor to the induced signal. We also simulate the positional variations of the DNA molecules on the sensitive surface. This computation yields an estimate for the amount of variation in the sensed signal due to the random placement of DNA molecules, and an estimate for the total signal-to-noise ratio is deduced.</p> / Doctor of Philosophy (PhD)