Piia Markkanen | University of Oulu (original) (raw)

Papers by Piia Markkanen

The aim of this diploma thesis work was to create new applications for intelligent and adaptive... more The aim of this diploma thesis work was to create new applications for intelligent and adaptive lighting in retail environment. Lighting is an important factor in generating atmosphere in retail space and it has been shown to affect customer behavior. Combining intelligent technology with lighting design enables new applications for creating an environment that senses the presence of the user. It can be employed to adapt the lighting to inform and guide the customer by creating visual focal points. Alternatively, the level of illumination can be adapted to the different requirements of the use, e.g. the presence of customers or employees.

The methods used in this study were scenario working and implementation. Four major themes were defined to approach the subject: 1. Navigation and guidance, 2. Product display and browsing, 3. Pleasure and entertainment, and 4. Natural light and simulated natural light. The themes were studied in a form of short stories written from point of view of both customer or designer, and the chosen applications were further studied and implemented in a hypermarket environment.

The implementations were presented as two case studies: Aisles and shelves and Landmarks and dynamic display lighting. The first case study describes lighting of the grocery store shelves. The following things were considered in the design: the noticeability of the ends of the shelves that have high value in product placement, the direction of the light, and the adaptability of lighting to the customer’s presence. An approaching customer triggers the sequential brightening of luminaires in between the shelves. The second case study considered focal points in retail environment and dynamic display lighting. In the lighting design, the landmarks, or focal points, are areas of interest that appeal and guide the customer. This is achieved in the design by using higher intensity of light compared to the surrounding environment or more colorful lighting. By displaying products under dynamic lighting, the changes in light intensity attract customer’s attention and increase the noticeability of products illuminated in this fashion.

Lighting is a versatile tool that can be easily used to change the appearance and atmosphere of retail environment from one season to another, keeping the store interesting and appealing to the customer. With current technology, these changes can be applied in an intelligent and adaptive manner: lighting can interact with customers and employees, and it can be made easily controllable for designers and visualists. The discovered applications can be applied to several types of retail environments, and depending on the application, also to other types of architectural spaces, for example museums and exhibition spaces.

AJP: Lung Cellular and Molecular Physiology, 2005

Peroxiredoxins (Prxs) are a group of thiol containing proteins that participate both in signal tr... more Peroxiredoxins (Prxs) are a group of thiol containing proteins that participate both in signal transduction and in the breakdown of hydrogen peroxide (H 2 O 2 ) during oxidative stress. Six distinct Prxs have been characterized in human cells (Prxs I-VI). Prxs I-IV form dimers held together by disulphide bonds, Prx V forms intramolecular bond, but the mechanism of Prx VI, so called 1-cys Prx, is still unclear. Here we describe the regulation of all six Prxs in cultured human lung A549 and BEAS2B cells. The cells were exposed to variable concentrations of H 2 O 2 , menadione, tumor necrosis factor or transforming growth factor . To evoke glutathione depletion the cells were furthermore treated with buthionine sulfoximine. Only high concentrations (300 µM) of H 2 O 2 caused a minor increase (<28%, 4h) in the expression of Prxs I, IV and VI. Severe oxidant stress (250-500 µM H 2 O 2 ) caused a significant increase in the proportion of the monomeric forms of Prxs I-IV, this was reversible at lower H 2 O 2 concentrations ( 250 µM). This recovery of Prx overoxidation differed among the various Prxs, Prx I was recovered within 24 hours but recovery required 48 hours for Prx III. Overall Prxs are not significantly modulated by mild oxidant stress or cytokines, but there is variable, though reversible, overoxidation in these proteins during severe oxidant exposure.

Journal of Biological Chemistry, 2006

Protein palmitoylation is a reversible lipid modification that plays important roles for many pro... more Protein palmitoylation is a reversible lipid modification that plays important roles for many proteins involved in signal transduction, but relatively little is known about the regulation of this modification and the cellular location where it occurs. We demonstrate that the human delta opioid receptor is palmitoylated at two distinct cellular locations in human embryonic kidney 293 cells and undergoes dynamic regulation at one of these sites. Although palmitoylation could be readily observed for the mature receptor (Mr 55,000), [3H]palmitate incorporation into the receptor precursor (Mr 45,000) could be detected only following transport blockade with brefeldin A, nocodazole, and monensin, indicating that the modification occurs initially during or shortly after export from the endoplasmic reticulum. Blocking of palmitoylation with 2-bromopalmitate inhibited receptor cell surface expression, indicating that it is needed for efficient intracellular transport. However, cell surface biotinylation experiments showed that receptors can also be palmitoylated once they have reached the plasma membrane. At this location, palmitoylation is regulated in a receptor activation-dependent manner, as was indicated by the opioid agonist-promoted increase in the turnover of receptor-bound palmitate. This agonist-mediated effect did not require receptor-G protein coupling and occurred at the cell surface without the need for internalization or recycling. The activation-dependent modulation of receptor palmitoylation may thus contribute to the regulation of receptor function at the plasma membrane.

In this paper, we present a qualitative exploration of customers' experiences of adaptive ret... more In this paper, we present a qualitative exploration of customers' experiences of adaptive retail lighting, reflecting on the evaluation results of three lighting schemes for the same retail space. Furthermore, we describe the innovative real-world research setting.

Proceedings of the 33rd Annual ACM Conference on Human Factors in Computing Systems - CHI '15, 2015

We introduce evaluation probes for conducting emic, experiential evaluation of urban technologies... more We introduce evaluation probes for conducting emic, experiential evaluation of urban technologies "in the wild" without direct researcher presence. We commence with a thorough discussion and analysis of the original cultural probes, used by Gaver, Dunne and Pacenti to gain design inspiration, and their subsequent variations. We develop the concept of evaluation probes through careful reconceptualization and application of the cultural probes in three successive studies conducted in the wild. We recount and reflect on our use of evaluation probes and discuss their merits and limitations in experiential emic evaluation.

Learning and research environments in academic campus context are undergoing fast changes. The ch... more Learning and research environments in academic campus context are undergoing fast changes. The changes are occurring both on the level of technology implemented to the environment and the space itself as the traditional cellular offices are increasingly being replaced by open work environments. Knowledge workers, such as the researchers, are at the core of creativity and innovation. The ideal working and learning environments support both creative thinking and collaborative interaction. This article explores the current understanding of the requirements of high quality research and learning environments, and it aims to examine the link between creativity and space. In doing so, I wish to highlight how the architecture of the workspace can respond to the requirements of a successful working environment and how immaterial elements, such as lighting for instance, can induce creative thought, achievement, and innovation and importantly enhance the well-being of the occupants of the space. Furthermore, I will look into how the architecture and technology of the space affect the dissemination of tacit and explicit knowledge amongst individuals and within groups. As part of my research project, aimed to provide new scientific information of the real user needs in academic working and learning environments and create concepts of hybrid multi-spaces, I will discuss in this paper how architecture and lighting design can support knowledge sharing, peer-to-peer interactions, creativity and innovation, which are imperative for success in knowledge work. Hence, the findings could inform the design of new learning and working environments suitable for both user expectations and knowledge production.

Journal of Biological Chemistry, 2007

Accumulating evidence has indicated that membrane-permeable G protein-coupled receptor ligands ca... more Accumulating evidence has indicated that membrane-permeable G protein-coupled receptor ligands can enhance cell surface targeting of their cognate wild-type and mutant receptors. This pharmacological chaperoning was thought to result from ligand-mediated stabilization of immature receptors in the endoplasmic reticulum (ER). In the present study, we directly tested this hypothesis using wild-type and mutant forms of the human delta-opioid receptor as models. ER-localized receptors were isolated by expressing the receptors in HEK293 cells under tightly controlled tetracycline induction and blocking their ER export with brefeldin A. The ER-retained delta-opioid receptor precursors were able to bind [(3)H]diprenorphine with high affinity, and treatment of cells with an opioid antagonist naltrexone led to a 2-fold increase in the number of binding sites. After removing the transport block, the antagonist-mediated increase in the number of receptors was detectable at the cell surface by flow cytometry and cell surface biotinylation assay. Importantly, opioid ligands, both antagonists and agonists, were found to stabilize the ER-retained receptor precursors in an in vitro heat inactivation assay and the treatment enhanced dissociation of receptor precursors from the molecular chaperone calnexin. Thus, we conclude that pharmacological chaperones facilitate plasma membrane targeting of delta-opioid receptors by binding and stabilizing receptor precursors, thereby promoting their release from the stringent ER quality control.

Journal of Biological Chemistry, 2008

A great majority of G protein-coupled receptors are modified by N-glycosylation, but the function... more A great majority of G protein-coupled receptors are modified by N-glycosylation, but the functional significance of this modification for receptor folding and intracellular transport has remained elusive. Here we studied these phenomena by mutating the two N-terminal N-glycosylation sites (Asn 18 and Asn 33 ) of the human ␦-opioid receptor, and expressing the mutants from the same chromosomal integration site in stably transfected inducible HEK293 cells. Both N-glycosylation sites were used, and their abolishment decreased the steady-state level of receptors at the cell surface. However, pulse-chase labeling, cell surface biotinylation, and immunofluorescence microscopy revealed that this was not because of intracellular accumulation. Instead, the non-N-glycosylated receptors were exported from the endoplasmic reticulum with enhanced kinetics. The results also revealed differences in the significance of the individual N-glycans, as the one attached to Asn 33 was found to be more important for endoplasmic reticulum retention of the receptor. The non-N-glycosylated receptors did not show gross functional impairment, but flow cytometry revealed that a fraction of them was incapable of ligand binding at the cell surface. In addition, the receptors that were devoid of N-glycans showed accelerated turnover and internalization and were targeted for lysosomal degradation. The results accentuate the importance of protein conformation-based screening before export from the endoplasmic reticulum, and demonstrate how the system is compromised when N-glycosylation is disrupted. We conclude that N-glycosylation of the ␦-opioid receptor is needed to maintain the expression of fully functional and stable receptor molecules at the cell surface.

The aim of this diploma thesis work was to create new applications for intelligent and adaptive... more The aim of this diploma thesis work was to create new applications for intelligent and adaptive lighting in retail environment. Lighting is an important factor in generating atmosphere in retail space and it has been shown to affect customer behavior. Combining intelligent technology with lighting design enables new applications for creating an environment that senses the presence of the user. It can be employed to adapt the lighting to inform and guide the customer by creating visual focal points. Alternatively, the level of illumination can be adapted to the different requirements of the use, e.g. the presence of customers or employees.

The methods used in this study were scenario working and implementation. Four major themes were defined to approach the subject: 1. Navigation and guidance, 2. Product display and browsing, 3. Pleasure and entertainment, and 4. Natural light and simulated natural light. The themes were studied in a form of short stories written from point of view of both customer or designer, and the chosen applications were further studied and implemented in a hypermarket environment.

The implementations were presented as two case studies: Aisles and shelves and Landmarks and dynamic display lighting. The first case study describes lighting of the grocery store shelves. The following things were considered in the design: the noticeability of the ends of the shelves that have high value in product placement, the direction of the light, and the adaptability of lighting to the customer’s presence. An approaching customer triggers the sequential brightening of luminaires in between the shelves. The second case study considered focal points in retail environment and dynamic display lighting. In the lighting design, the landmarks, or focal points, are areas of interest that appeal and guide the customer. This is achieved in the design by using higher intensity of light compared to the surrounding environment or more colorful lighting. By displaying products under dynamic lighting, the changes in light intensity attract customer’s attention and increase the noticeability of products illuminated in this fashion.

Lighting is a versatile tool that can be easily used to change the appearance and atmosphere of retail environment from one season to another, keeping the store interesting and appealing to the customer. With current technology, these changes can be applied in an intelligent and adaptive manner: lighting can interact with customers and employees, and it can be made easily controllable for designers and visualists. The discovered applications can be applied to several types of retail environments, and depending on the application, also to other types of architectural spaces, for example museums and exhibition spaces.

AJP: Lung Cellular and Molecular Physiology, 2005

Peroxiredoxins (Prxs) are a group of thiol containing proteins that participate both in signal tr... more Peroxiredoxins (Prxs) are a group of thiol containing proteins that participate both in signal transduction and in the breakdown of hydrogen peroxide (H 2 O 2 ) during oxidative stress. Six distinct Prxs have been characterized in human cells (Prxs I-VI). Prxs I-IV form dimers held together by disulphide bonds, Prx V forms intramolecular bond, but the mechanism of Prx VI, so called 1-cys Prx, is still unclear. Here we describe the regulation of all six Prxs in cultured human lung A549 and BEAS2B cells. The cells were exposed to variable concentrations of H 2 O 2 , menadione, tumor necrosis factor or transforming growth factor . To evoke glutathione depletion the cells were furthermore treated with buthionine sulfoximine. Only high concentrations (300 µM) of H 2 O 2 caused a minor increase (<28%, 4h) in the expression of Prxs I, IV and VI. Severe oxidant stress (250-500 µM H 2 O 2 ) caused a significant increase in the proportion of the monomeric forms of Prxs I-IV, this was reversible at lower H 2 O 2 concentrations ( 250 µM). This recovery of Prx overoxidation differed among the various Prxs, Prx I was recovered within 24 hours but recovery required 48 hours for Prx III. Overall Prxs are not significantly modulated by mild oxidant stress or cytokines, but there is variable, though reversible, overoxidation in these proteins during severe oxidant exposure.

Journal of Biological Chemistry, 2006

Protein palmitoylation is a reversible lipid modification that plays important roles for many pro... more Protein palmitoylation is a reversible lipid modification that plays important roles for many proteins involved in signal transduction, but relatively little is known about the regulation of this modification and the cellular location where it occurs. We demonstrate that the human delta opioid receptor is palmitoylated at two distinct cellular locations in human embryonic kidney 293 cells and undergoes dynamic regulation at one of these sites. Although palmitoylation could be readily observed for the mature receptor (Mr 55,000), [3H]palmitate incorporation into the receptor precursor (Mr 45,000) could be detected only following transport blockade with brefeldin A, nocodazole, and monensin, indicating that the modification occurs initially during or shortly after export from the endoplasmic reticulum. Blocking of palmitoylation with 2-bromopalmitate inhibited receptor cell surface expression, indicating that it is needed for efficient intracellular transport. However, cell surface biotinylation experiments showed that receptors can also be palmitoylated once they have reached the plasma membrane. At this location, palmitoylation is regulated in a receptor activation-dependent manner, as was indicated by the opioid agonist-promoted increase in the turnover of receptor-bound palmitate. This agonist-mediated effect did not require receptor-G protein coupling and occurred at the cell surface without the need for internalization or recycling. The activation-dependent modulation of receptor palmitoylation may thus contribute to the regulation of receptor function at the plasma membrane.

In this paper, we present a qualitative exploration of customers' experiences of adaptive ret... more In this paper, we present a qualitative exploration of customers' experiences of adaptive retail lighting, reflecting on the evaluation results of three lighting schemes for the same retail space. Furthermore, we describe the innovative real-world research setting.

Proceedings of the 33rd Annual ACM Conference on Human Factors in Computing Systems - CHI '15, 2015

We introduce evaluation probes for conducting emic, experiential evaluation of urban technologies... more We introduce evaluation probes for conducting emic, experiential evaluation of urban technologies "in the wild" without direct researcher presence. We commence with a thorough discussion and analysis of the original cultural probes, used by Gaver, Dunne and Pacenti to gain design inspiration, and their subsequent variations. We develop the concept of evaluation probes through careful reconceptualization and application of the cultural probes in three successive studies conducted in the wild. We recount and reflect on our use of evaluation probes and discuss their merits and limitations in experiential emic evaluation.

Learning and research environments in academic campus context are undergoing fast changes. The ch... more Learning and research environments in academic campus context are undergoing fast changes. The changes are occurring both on the level of technology implemented to the environment and the space itself as the traditional cellular offices are increasingly being replaced by open work environments. Knowledge workers, such as the researchers, are at the core of creativity and innovation. The ideal working and learning environments support both creative thinking and collaborative interaction. This article explores the current understanding of the requirements of high quality research and learning environments, and it aims to examine the link between creativity and space. In doing so, I wish to highlight how the architecture of the workspace can respond to the requirements of a successful working environment and how immaterial elements, such as lighting for instance, can induce creative thought, achievement, and innovation and importantly enhance the well-being of the occupants of the space. Furthermore, I will look into how the architecture and technology of the space affect the dissemination of tacit and explicit knowledge amongst individuals and within groups. As part of my research project, aimed to provide new scientific information of the real user needs in academic working and learning environments and create concepts of hybrid multi-spaces, I will discuss in this paper how architecture and lighting design can support knowledge sharing, peer-to-peer interactions, creativity and innovation, which are imperative for success in knowledge work. Hence, the findings could inform the design of new learning and working environments suitable for both user expectations and knowledge production.

Journal of Biological Chemistry, 2007

Accumulating evidence has indicated that membrane-permeable G protein-coupled receptor ligands ca... more Accumulating evidence has indicated that membrane-permeable G protein-coupled receptor ligands can enhance cell surface targeting of their cognate wild-type and mutant receptors. This pharmacological chaperoning was thought to result from ligand-mediated stabilization of immature receptors in the endoplasmic reticulum (ER). In the present study, we directly tested this hypothesis using wild-type and mutant forms of the human delta-opioid receptor as models. ER-localized receptors were isolated by expressing the receptors in HEK293 cells under tightly controlled tetracycline induction and blocking their ER export with brefeldin A. The ER-retained delta-opioid receptor precursors were able to bind [(3)H]diprenorphine with high affinity, and treatment of cells with an opioid antagonist naltrexone led to a 2-fold increase in the number of binding sites. After removing the transport block, the antagonist-mediated increase in the number of receptors was detectable at the cell surface by flow cytometry and cell surface biotinylation assay. Importantly, opioid ligands, both antagonists and agonists, were found to stabilize the ER-retained receptor precursors in an in vitro heat inactivation assay and the treatment enhanced dissociation of receptor precursors from the molecular chaperone calnexin. Thus, we conclude that pharmacological chaperones facilitate plasma membrane targeting of delta-opioid receptors by binding and stabilizing receptor precursors, thereby promoting their release from the stringent ER quality control.

Journal of Biological Chemistry, 2008

A great majority of G protein-coupled receptors are modified by N-glycosylation, but the function... more A great majority of G protein-coupled receptors are modified by N-glycosylation, but the functional significance of this modification for receptor folding and intracellular transport has remained elusive. Here we studied these phenomena by mutating the two N-terminal N-glycosylation sites (Asn 18 and Asn 33 ) of the human ␦-opioid receptor, and expressing the mutants from the same chromosomal integration site in stably transfected inducible HEK293 cells. Both N-glycosylation sites were used, and their abolishment decreased the steady-state level of receptors at the cell surface. However, pulse-chase labeling, cell surface biotinylation, and immunofluorescence microscopy revealed that this was not because of intracellular accumulation. Instead, the non-N-glycosylated receptors were exported from the endoplasmic reticulum with enhanced kinetics. The results also revealed differences in the significance of the individual N-glycans, as the one attached to Asn 33 was found to be more important for endoplasmic reticulum retention of the receptor. The non-N-glycosylated receptors did not show gross functional impairment, but flow cytometry revealed that a fraction of them was incapable of ligand binding at the cell surface. In addition, the receptors that were devoid of N-glycans showed accelerated turnover and internalization and were targeted for lysosomal degradation. The results accentuate the importance of protein conformation-based screening before export from the endoplasmic reticulum, and demonstrate how the system is compromised when N-glycosylation is disrupted. We conclude that N-glycosylation of the ␦-opioid receptor is needed to maintain the expression of fully functional and stable receptor molecules at the cell surface.