VTT Technical Research Center of Finland
VTT Technical Research Center of Finland
University of Warwick and VTT Technical Research Center of Finland | Date: 2014-11-04
A bolometer is described. A bolometer includes a superconductor-insulator-semiconductor-superconductor structure or a superconductor-insulator-semiconductor-insulator-superconductor structure. The semiconductor comprises an electron gas in a layer of silicon, germanium or silicon-germanium alloy in which valley degeneracy is at least partially lifted. The insulator or a one or both of the insulators may comprise a layer of dielectric material. The insulator or a one or both of the insulators may comprise a layer of non-degenerately doped semiconductor.
Leivonen S.K.,VTT Technical Research Center of Finland
Molecular & cellular proteomics : MCP | Year: 2011
Identification of protein targets for microRNAs (miRNAs) is a significant challenge due to the complexity of miRNA-mediated regulation. We have previously demonstrated that miR-193b targets estrogen receptor-α (ERα) and inhibits estrogen-induced growth of breast cancer cells. Here, we applied a high-throughput strategy using quantitative iTRAQ (isobaric tag for relative and absolute quantitation) reagents to identify other target proteins regulated by miR-193b in breast cancer cells. iTRAQ analysis of pre-miR-193b transfected MCF-7 cells resulted in identification of 743 unique proteins, of which 39 were down-regulated and 44 up-regulated as compared with negative control transfected cells. Computationally predicted targets of miR-193b were highly enriched (sevenfold) among the proteins whose level of expression decreased after miR-193b transfection. Only a minority of these (13%) showed similar effect at the mRNA level illustrating the importance of post-transcriptional regulation. The most significantly repressed proteins were selected for validation experiments. These data confirmed 14-3-3ζ (YWHAZ), serine hydroxyl transferase (SHMT2), and aldo-keto reductase family 1, member C2 (AKR1C2) as direct, previously uncharacterized, targets of miR-193b. Functional RNAi assays demonstrated that specific combinations of knockdowns of these target genes by siRNAs inhibited growth of MCF-7 cells, mimicking the effects of the miR-193b overexpression. Interestingly, the data imply that besides targeting ERα, the miR-193b effects include suppression of the local production of estrogens and other steroid hormones mediated by the AKR1C2 gene, thus provoking two separate molecular mechanisms inhibiting steroid-dependent growth of breast cancer cells. In conclusion, we present here a proteomic screen to identify targets of miR-193b, and a systems biological approach to mimic its effects at the level of cellular phenotypes. This led to the identification of multiple genes whose combinatorial knock-down likely mediates the strong anti-cancer effects observed for miR-193b in breast cancer cells.
Ivaska J.,VTT Technical Research Center of Finland
Nature Cell Biology | Year: 2012
Focal adhesions are large structures through which integrins and scaffold proteins link the actin cytoskeleton to the extracellular matrix. A detailed analysis of integrin dynamics now indicates that focal-adhesion-associated integrins constantly switch between active and immobilized, and unbound and free-diffusing states, with different fibronectin-binding integrin heterodimers showing distinct focal-adhesion dynamics. © 2012 Macmillan Publishers Limited. All rights reserved.
Oresic M.,VTT Technical Research Center of Finland
Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids | Year: 2011
The ability to translate vast amounts of information, as obtained from lipidomic analysis, into the knowledge and understanding of biological phenomena is an important challenge faced by the lipidomics community. While many of the informatics and computational tools from other domains such as bioinformatics and metabolomics are also applicable to lipidomics data processing and analysis, new solutions and strategies are needed for the studies of lipidomes at the systems level. This is due to enormous functional and structural diversity of lipids as well as because of their complex regulation at multiple spatial and temporal scales. In order to better understand the lipidomes at the physiological level, lipids need to be modeled not only at the level of biological pathways but also at the level of the biophysical systems they are part of, such as cellular membranes or lipoprotein particles. Herein the current state, recent advances and new opportunities in the field of lipid bioinformatics are reviewed. This article is part of a Special Issue entitled Lipodomics and Imaging Mass Spectrometry. © 2011 Elsevier B.V.
Haapio A.,VTT Technical Research Center of Finland
Environmental Impact Assessment Review | Year: 2012
Requirements for the assessment tools of buildings have increased, assessing of building components or separate buildings is not enough. Neighbourhoods, built environment, public transportations, and services, should be considered simultaneously. Number of population living in urban areas is high and increasing rapidly. Urbanisation is a major concern due to its detrimental effects on the environment. The aim of this study is to clarify the field of assessment tools for urban communities by analysing the current situation. The focus is on internationally well known assessment tools; BREEAM Communities, CASBEE for Urban Development and LEED for Neigborhood Development.The interest towards certification systems is increasing amongst the authorities, and especially amongst the global investors and property developers. Achieved certifications are expected to bring measureable publicity for the developers. The assessment of urban areas enables the comparison of municipalities and urban areas, and notably supports decision making processes. Authorities, city planners, and designers would benefit most from the use of the tools during the decision making process. © 2011 Elsevier Inc.
Karjalainen S.,VTT Technical Research Center of Finland
Energy and Buildings | Year: 2011
Numerous studies have shown that feedback on energy consumption can work to effectively reduce household energy consumption. However, relatively little work has been done on the best ways to present information in order to maximise energy savings. In this work, different ways of presenting feedback on electricity consumption were systematically analysed and user interface prototypes were developed based on the analysis. The prototypes were shown to consumers in qualitative interviews to gain information on how well they understood them and what kind of feedback they prefer to receive on their electricity consumption. The results show that the following features of feedback on electricity consumption are most valued by consumers: presentations of costs (over a period of time), appliance-specific breakdown, i.e. information on what proportion is consumed by each appliance, and historical comparison, i.e. comparison with their own prior consumption. © 2010 Elsevier B.V. All rights reserved.
Karjalainen S.,VTT Technical Research Center of Finland
Indoor Air | Year: 2012
This review examines scientific literature on the effect of gender on indoor thermal comfort. Gender differences have been generally considered to be small and insignificant but this review shows that a growing number of studies have found significant differences in thermal comfort between the genders. Clearly more than half of the laboratory and field studies have found that females express more dissatisfaction than males in the same thermal environments. Very few studies have found males to be more dissatisfied than females. A meta-analysis shows that females are more likely than males to express thermal dissatisfaction (ratio: 1.74, 95% confidence interval: 1.61-1.89). However, most studies found no significant difference in neutral temperatures between the genders. Females are more sensitive than males to a deviation from an optimal temperature and express more dissatisfaction, especially in cooler conditions. © 2011 John Wiley & Sons A/S.
Pentikousis K.,VTT Technical Research Center of Finland
IEEE Communications Magazine | Year: 2010
With the proliferation of mobile fixed-power devices, energy consumption emerged as a vibrant research and development subject area in networking. Mobile devices are designed with several hard constraints such as low cost and small geometries, as well as, low heat dissipation, and operation using fixed power sources. Manufacturers have been adding an ever increasing set of features to small mobile devices, which are no longer binary-use gadgets, but fully-fledged computers. With respect to power management, several mechanisms have been introduced; but, by and large, gains in power consumption at the hardware level have been essentially traded for extended functionality. All in all, the overall operational time has not increased. For example, early GSM cellular phones could only allow for less than an hour of talk time in a single battery charge. By the late 1990s, top models, introduced through better engineering and an evolutionary development approach, featured talk times increased by a factor of 3-5. This level of performance has remained the same over the last decade, although it is well below user expectations. This article reviews the evolution from simple cell phones toward the feature-rich mobile networked devices we have come to expect from manufacturers, and explains the factors that have led to stagnation in operational time. We then turn our attention to the multiaccess nature of modern mobile devices and the respective implications for power management. We find that the current host-centric mobile networking paradigm, based on end-to-end always on connectivity, leads to energy-inefficient operation. Finally, this article introduces information-centric networking and outlines open research issues in the design of energy-efficient future Internet architectures. © 2010 IEEE.
Raty T.D.,VTT Technical Research Center of Finland
IEEE Transactions on Systems, Man and Cybernetics Part C: Applications and Reviews | Year: 2010
Surveillance systems provide the capability of collecting authentic and purposeful information and forming appropriate decisions to enhance safety. This paper reviews concisely the historical development and current state of the three different generations of contemporary surveillance systems. Recently, in addition to the employment of the incessantly enlarging variety of sensors, the inclination has been to utilize more intelligence and situation awareness capabilities to assist the human surveillance personnel. The most recent generation is decomposed into multisensor environments, video and audio surveillance, wireless sensor networks, distributed intelligence and awareness, architecture and middleware, and the utilization of mobile robots. The prominent difficulties of the contemporary surveillance systems are highlighted. These challenging dilemmas are composed of the attainment of real-time distributed architecture, awareness and intelligence, existing difficulties in video surveillance, the utilization of wireless networks, the energy efficiency of remote sensors, the location difficulties of surveillance personnel, and scalability difficulties. The paper is concluded with concise summary and the future of surveillance systems for public safety. © 2010 IEEE.
VTT Technical Research Center of Finland and The Regents Of The University Of California | Date: 2015-12-09
Disclosed are methods of manufacturing a SH surface including: creating a master with SH features by: depositing a rigid material onto a first surface, wherein the first surface is a shrinkable platform; shrinking the first surface by heating to create a SH surface, wherein the SH surface has micro- and nano-scale structural features that trap air pockets and prevent water from wetting the surface; forming the master by molding an epoxy with the shrunken first surface having a SH surface, wherein the master acquires the SH features of the first surface; and imprinting the SH features of the master onto a second surface to impart the SH features of the master onto the second surface. Some embodiments relate to a superhydrophobic (SH) surface, an article including a SH surface as disclosed, such as a microfluidic device or a food container.