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A Renewed Look at Zeros of Sampled-Data Systems—From the Lifting Viewpoint

This paper studies the properties of the zeros of sampled-data systems. Since the basic study by Åström et al. that showed there can exist unstable zeros that have no relevance to the original continuous-time plant, there have been various studies that circumvent this effect by introducing various techniques. The present paper studies zeros of sampled-data systems from the standpoint of lifting. W

Topology-independent robust stability of homogeneous dynamic networks

The paper presents conditions for the stability of a dynamical network described by a directed graph, whose nodes represent dynamical systems characterised by the same transfer function F(s) and whose edges account for the interactions between pairs of nodes. In turn, these interactions depend via a transference G(s) on the outputs of the subsystems associated with the connected nodes. The stabili

Insights into charge carrier dynamics in organo-metal halide perovskites : From neat films to solar cells

Organo-metal halide perovskites have recently obtained world-wide attention as promising solar cell materials. They have broad and strong light absorption along with excellent carrier transport properties which partially explain their record power conversion efficiencies above 22%. However, the basic understanding of the underlying physical mechanisms is still limited and there remain large discre

Change of mammographic density predicts the risk of contralateral breast cancer--a case-control study

INTRODUCTION: Mammographic density is a strong risk factor for breast cancer, but it is unknown whether density at first breast cancer diagnosis and changes during follow-up influences risk of non-simultaneous contralateral breast cancer (CBC).METHODS: We collected mammograms for CBC-patients (cases, N = 211) and unilateral breast cancer patients (controls, N = 211), individually matched on age an

Similar alpha and beta diversity changes in tropical ant communities, comparing savannas and rainforests in Brazil and Indonesia

Local biodiversity can be expected to be similar worldwide if environmental conditions are similar. Here, we hypothesize that tropical ant communities with different types of regional species pools but at similar habitat types in Brazil and Indonesia show similar diversity patterns at multiple spatial scales, when comparing (1) the relative contribution of alpha and beta diversity to gamma diversi

In the name of managerialism : Reforming organizations in the Swedish public sector

This paper focuses on the translation of managerialism in the Swedish public sector. A field study of the attempts by two large municipalities to launch a grand reform in the name of managerialism, that is, a purchasersupplier reform, shows the by now familiar difficulties of trying to change public organizations. Thus the actual consequences of actions taken in the name of managerialism are perha

High-throughput identification of small molecules that affect human embryonic vascular development

Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and limited mechanistic information regarding the biological pathways and pot

Differences in the epigenetic and reprogramming properties of pluripotent and extra-embryonic stem cells implicate chromatin remodelling as an important early event in the developing mouse embryo

Background. During early mouse development, two extra-embryonic lineages form alongside the future embryo: the trophectoderm (TE) and the primitive endoderm (PrE). Epigenetic changes known to take place during these early stages include changes in DNA methylation and modified histones, as well as dynamic changes in gene expression. Results. In order to understand the role and extent of chromatin-b

Isoprenoid emission variation of Norway spruce across a European latitudinal transect

Norway spruce (Picea abies) is one of the dominant tree species in the European boreal zone with the capacity to grow over large areas within Europe. It is an important emitter of biogenic volatile organic compounds (BVOCs), which can act as precursors of photochemical smog and ozone and contribute to the formation and growth of secondary organic aerosols (SOA) in the atmosphere.Isoprenoid emissio

Sweden: internal migration in a high-migration Nordic country

Sweden was historically, and remains, a high-migration country. The chapter considers its experience using the census and population register data that are available for the analysis of migration over long historical periods, assessing their strengths and weaknesses. It then outlines levels of inter-parish moves from 1900 to 2015 as well as moves over shorter distances from the 1970s. The former o

PPC operation with low ron gasoline fuel. A study on load range on a euro 6 light duty diesel engine

Gasoline Partially Premixed Combustion (PPC) is a promising alternative combustion concept that can offer both high indicated efficiency and low exhaust emissions in terms of NOx and soot, compared to conventional diesel combustion (CDC). Previous research has shown that PPC can operate with gasoline-like fuels of varying RON numbers. Some of the most promising results come with the use of gasolin

Seasonal variation in biogenic volatile organic compound (BVOC) emissions from Norway spruce in a Swedish boreal forest

Terpene emissions from the top-canopy layer (at 20 m) of one 118-year-old Norway spruce tree were measured between June and September 2013 using a branch chamber. Total terpene emissions varied from 0.05 to 332.5 μg gdw -1 h-1 with a peak in August. Monoterpenes dominated throughout the summer and on average accounted for 65% of the total terpene mass, followed by sesquiterpenes (29%) and isoprene