Akita University of Art: AUA Repository / 秋田公立美術大学リポジトリ
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New avenues in PET imaging of multiple sclerosis
No full textMultiple sclerose is een neurodegeneratieve aandoening waarbij ontstekingen en het verlies van de myelineschede rondom de zenuwvezels leidt tot ernstige neurologische verschijnselen. Positron Emissie Tomografie (PET) is een beeldvormende techniek waarmee het ontstaan en de voortgang van ziekteprocessen in het centraal zenuwstelsel zichtbaar gemaakt kan worden. Bij PET wordt een kortlevende radioactieve stof, een “tracer”, intraveneus geïnjecteerd, waarna een 3D afbeelding van ons lichaam kan worden verkregen. Uit de PET scan kan specifieke moleculair informatie over (afwijkingen in) fysiologische en biochemische processen in de patiënt worden verkregen. Het doel van het onderzoek beschreven in dit proefschrift is het evalueren van de mogelijkheid om PET te gebruiken voor het vaststellen van myelineverlies en het volgen van ontstekingsprocessen in het zenuwstelsel van proefdieren waarin MS is opgewekt. Uit ons PET onderzoek met een specifieke tracer voor ontstekingen in de hersenen, [11C]PK11195, bleek dat de activering van ontstekingscellen in de hersenen uitstekend kan worden gevolgd. PET bleek ook een gevoelige methode te zijn om het effect van ontstekingsremmende middelen te meten. Daarnaast hebben wij nieuwe PET tracers voor het afbeelden myeline geëvalueerd in diermodellen voor MS en aangetoond dat met name de tracer [11C]MeDAS geschikt is om afbraak en herstel van myeline in de hersenen en het ruggenmerg zichtbaar te maken. Echter, deze tracer in de kliniek kan worden gebruikt, zal eerst de veiligheid en specificiteit verder getest moeten worden. Ons onderzoek heeft laten zien dat PET nieuwe mogelijkheden biedt om de ziekteprocessen in het zenuwstelsel van MS patiënten in beeld te brengen
Charge Transport through Self-Assembled Monolayers with Eutectic Gallium-Indium Top Contacts
No full textMoleculaire geleiding in self-assembled monolayers In zijn proefschrift presenteert Davide Fracasso een breed overzicht van tunneling junctions uit self-asssembled monolayers (SAMs) met een top-elektrode bestaande uit Eutectisch Gallium Indium (EGaIn). Fracasso introduceert enkele concepten van moleculaire elektronica, SAMs en tunneling junctions. Hij vergelijkt twee technieken voor het metende eigenschappen van ladingstransport: de kwikdruppel- en de EGaIn-methode. EGaIn is een relatief nieuwe techniek in de wereld van de moleculaire elektronica die snel in opmars is in verschillende onderzoekslaboratoria. Het vermogen om moleculaire geleiding te beheersen is essentieel voor functionele moleculaire elektronische devices, stelt Fracasso. Over het algemeen zijn onderzoekers van moleculaire elektronica geïnteresseerd in actieve moleculaire componenten en nieuwe functionaliteiten. De vraag hoe moleculen de prestaties van een device beïnvloeden is daarbij zeer belangrijk, vindtFracasso. In de praktijk gaat inzicht van de elektronische eigenschappen echter vaak verscholen achter de complexiteit van de architectuur van het device, in sommige gevallen zijn de prestaties belangrijker dan het achterliggende begrip. Fracasso benadrukt het fundamentele karakter van zijn onderzoek. ’Ik laat zien hoe EGaIn gebruikt kan worden als conformele top-elektrode om nieuwe moleculaire verschijnselen bloot te leggen. Het doel daarvan was om SAMs elektronisch te karakteriseren en chemische structuren aan hun functionaliteiten te correleren, niet om industrieel bruikbare devices te maken.’In this thesis a broad overview of tunneling junctions comprising SAMs with eutectic Gallium Indium as top electrode is presented.I at first introduce the concepts of Molecular Electronics, SAMs, tunneling junctions, and compared two techniques to measure charge transport properties, Hg-drop and EGaIn, which have their state of matter in common: being liquid at room temperature. EGaIn, despite being a relatively new technique in the world of Molecular Electronics, rapidly caught the attention of several research laboratories.Controlling molecular conductance is an essential requirement on the road towards functional molecular electronic devices. The field of molecular electronics is generally interested in active molecular components and new functionalities. An important issue in molecular electronics is the understanding on how the molecules govern the device performance. The understanding of the electrical properties is often hidden behind the complexity of the devices architecture, in some cases the performances of the device are more important than the deeper understanding, i.e. function trumps spectroscopy. I showed in this thesis how EGaIn can be used as conformal top electrode to uncover new molecular phenomena. The goal of my research was not to develop devices for industrial application, rather to characterize SAMs electrically and correlate chemical structures to functionalities
Going Backward:A Flexible Geometric Approach to Reverse Transformation from Coarse Grained to Atomistic Models
No full textThe conversion of coarse-grained to atomistic models is an important step in obtaining insight about atomistic scale processes from coarse-grained simulations. For this process, called backmapping or reverse transformation, several tools are available, but these commonly require libraries of molecule fragments or they are linked to a specific software package. In addition, the methods are usually restricted to specific molecules and to a specific force field. Here, we present an alternative method, consisting of geometric projection and subsequent force-field based relaxation. This method is designed to be simple and flexible, and offers a generic solution for resolution transformation. For simple systems, the conversion only requires a list of particle correspondences on the two levels of resolution. For special cases, such as nondefault protonation states of amino acids and virtual sites, a target particle list can be specified. The mapping uses simple building blocks, which list the particles on the different levels of resolution. For conversion to higher resolution, the initial model is relaxed with several short cycles of energy minimization and position-restrained MD. The reconstruction of an atomistic backbone from a coarse-grained model is done using a new dedicated algorithm. The method is generic and can be used to map between any two particle based representations, provided that a mapping can be written. The focus of this work is on the coarse-grained MARTINI force field, for which mapping definitions are written to allow conversion to and from the higher-resolution force fields GROMOS, CHARMM, and AMBER, and to and from a simplified three-bead lipid model. Together, these offer the possibility to simulate mesoscopic membrane structures, to be transformed to MARTINI and subsequently to an atomistic model for investigation of detailed interactions. The method was tested on a set of systems ranging from a simple, single-component bilayer to a large protein−membrane−solvent complex. The results demonstrate the efficiency and the efficacy of the new approach
Low-frequency Raman study of the ferroelectric phase transition in a layered CuCl4-based organic-inorganic hybrid
No full textThe ferroelectric phase transition at T-C = 340 K in (C6H5CH2CH2NH3)(2)CuCl4 is studied by means of temperature-dependent low-frequency Raman scattering, focusing on the coupling of a low-energy librational mode to the order parameter of the transition. Analysis of the symmetry and characteristics of this mode links the dipolar order to the tilt angle of the organic cations. The thermal evolution of the Raman spectrum demonstrates the displacive component of the phase transition in combination with order-disorder phenomena and the importance of the organic-inorganic interplay to the physical properties of the compound. The ferroelectric properties investigated here can be generalized to the family of layered organic-inorganic hybrids.</p
Mystery callers: just like humans
No full textMystery calling is a specific form of mystery guest-research. With this type of marketing research one can evaluate telephone contacts with customers. In this contribution we evaluate how mystery callers judge the service quality of a customer contact centre of a service organisation. We compare the judgement of mystery callers with the judgment that customers give to the services of the customer contact center. For two important customer experience metrics (satisfaction and gratitude) we do not find significant differences between mystery callers and customers. Only for one of the three metrics we find a difference between the mystery callers and the customers. In our survey we also analyse if characteristics of the mystery callers influence their judgment. Two variables appear to affect the MC’s judgment: the degree of experience of the mystery caller, and the fact that the caller is a customer of the service organisation. We recommend to pay attention to a regular refreshment of the panel of mystery callers
How does earnings management influence investor's perceptions of firm value? Survey evidence from financial analysts
No full textSurvey evidence shows CFOs to believe that earnings management can enhance investor valuation of their firms. This evidence raises the question of correspondence between the beliefs of CFOs and investors. Surveying financial analysts to gain insight into how earnings management influences investor perception of firm value, we find analysts' and CFOs' beliefs to be generally consistent. We find that analysts perceive meeting earnings benchmarks and smoothing earnings to enhance investor perception of firm value and all earnings management actions to reach a benchmark, save share repurchases, to be value destroying. CFOs, however, are reluctant to repurchase shares, preferring to use techniques viewed by analysts as value destroying (e.g., reductions in discretionary spending). Analysts' inability to unravel such techniques perhaps explains CFOs' preferences
Function-technology platforms improve efficiency in high-tech equipment manufacturing: A case study in complex products and systems (CoPS)
No full textIntelligent products for enhancing the utilization of tracking technology in transportation
No full textPurpose – Many transportation companies struggle to effectively utilize the information provided by tracking technology for performing operational control. The research as presented in this paper aims to identify the problems underlying the inability to utilize tracking technology within this context. Moreover, this paper aims to contribute to solving these problems by proposing a set of design principles based on the concept of intelligent products.Design/methodology/approach – The study as described in this paper adopts a design science research methodology consisting of three phases. First, a case study in a transportation company has been performed to identify the problems faced when utilizing tracking technology. Second, to overcome these problems, a set of design principles has been formulated. Finally, a prototype system based on the design principles has been developed and subjected to experimental and observational evaluation.Findings – This paper identifies the problems associated with the utilization of tracking technology for the control of transport operations. Moreover, the proposed design principles support the development of information systems which overcome the identified problems and thereby enhance the utilization of tracking technology in a transportation context.Originality/value – The commonly held perception that tracking technology will improve the ability to perform operational control does not unequivocally stand up to empirical scrutiny. While it is widely demonstrated that tracking technology is able to accurately capture the detailed operational information, it remains a fundamental challenge to transform this abundance of information into accurate and timely control decisions. This research provides a valuable contribution with respect to tackling this challenge, by identifying problems and providing solutions related to the utilization of readily available tracking technology
Rich Ties and Innovative Knowledge Transfer within a Firm
No full textWe show that contacts in formal, informal and especially multiplex networks explain transfer of innovative knowledge in an organization. The contribution of informal contacts has been much acknowledged, while that of formal contacts did not receive much attention in the literature in recent decades. No study thus far has included both these different kinds of contacts in a firm, let alone considered their combined effect. The exact overlap between formal as well as informal contacts between individuals, forming multiplex or what we call rich ties because of their contribution, especially drives the transfer of new, innovative knowledge in a firm. Studying two cases in very different settings suggests these rich ties have a particularly strong effect on knowledge transfer in an organization, even when controlling for the strength of ties. Some of the effects on knowledge transfer in an organization previously ascribed to either the formal network or the informal network may actually be due to their combined effect in a rich tie.</p
Information provision by interest groups
No full textWe investigate interest groups’ incentives to inform consumers about the damaging practices of firms and the impact such an IG has on firms’ technology choices. The IG aims to reduce the production of some bad, say pollution. It can at a cost investigate firms’ production practices and inform consumers about its findings. Since consumers care about the environment, revealing differences in pollution levels between firms leads to vertical product differentiation. The information, by shifting sales from ‘dirty’ towards ‘clean’ firms, reduces pollution. We show that the IG is most inclined to investigate firms in relatively competitive industries and that the threat of being unmasked as a polluter prompts dirty firms to adopt a clean technology