93 research outputs found

    Mining Emotions from the Finnish War Letter Collection, 1939–1944

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    Our paper analyses emotional language used by Finnish soldiers and civilians in their private communication during World War II. The dataset consists of 7,000 handwritten letters converted into a machine-readable corpus with rich metadata. The dataset offers a unique opportunity to make a statistical analysis of people’s emotional responses to the war. We engage in key questions of the cultural history of war, such as the connection between soldiers’ emotional language and violence: did soldiers’ emotional language become more laconic in the course of the war? While computational approaches to mining emotions have been common in fields like computer science and linguistics, they have not gained wider popularity in historical research. Pioneering attempts have been based on individual emotion words carefully chosen by an historian, or on readily available, more generic emotion lexicons. Compared to machine-learning solutions, lexicon-based approaches require less computational effort and are more transparent to interpret. Our methodology combines the ready-made word list FEIL with contextual knowledge of historians. FEIL gives around 7,000 Finnish words an emotion category and intensity ratings. First, the emotion lexicon was filtered based on high intensity. Then the domain expert manually removed words not particularly emotionally intensive in the context of war letters. The expert also annotated the list of the most frequent words in the war letter collection and handpicked emotionally intensive words not included in FEIL. Our final list covered 298 emotion words. We quantified changes in their use over time. In contrast to earlier research, our analysis indicates that soldiers’ and civilians’ emotionality did not significantly differ during World War II. Soldiers’ use of emotion words saw a decline in the last stages of the war, but overall their letters were almost as emotional as the civilians’ letters. We did indeed identify some changes in the individual emotion words used by the soldiers in their letters: patriotic words in particular decreased in the course of the war. In addition to empirical findings, our paper sheds light on the problem of universal emotion lexicons in historical research: linguistic, cultural and temporal differences between present-day lexicons and historical datasets can lead to biased interpretations. Thus, our paper contributes not only to the history of emotions but also to emotion mining, which is historically sensitive.publishedVersionPeer reviewe

    Lasten ja nuorten osallistumisen edellytykset kouluyhteisöissä perusopetuksen rehtoreiden asiantuntijapuheessa

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    Tutkimuksessa tarkastellaan, miten rehtorit tulkitsevat kouluyhteisöjen edellytyksiä tukea lasten ja nuorten osallistumista. Osallistuminen määritellään lasten ja nuorten mahdollisuuksiksi olla mukana päätöksenteossa, vaikuttaa kouluyhteisön kehittämiseen ja harjoittaa aktiivista toimijuutta kouluyhteisössä. Asiantuntijapuhe on rehtoreiden puhetta lasten ja nuorten osallistumisen käytännöistä ja osallistumisen merkityksestä kouluyhteisöissä. Empiirisen aineiston muodostivat lappilaisilta rehtoreilta (N=15) kerätyt temaattiset yksilöhaastattelut. Aineiston analyysi tehtiin aineistolähtöisellä sisällönanalyysilla. Tuloksina muodostui neljä luokkaa, jotka tarkastelevat osallistumisen mahdollisuuksia, haasteita, reunaehtoja ja koulun toimintakulttuuria. Rehtorit tulkitsevat kouluyhteisöjen edellytyksiä lasten ja nuorten osallistumisen tukemiseen moninäkökulmaisesti. Kouluyhteisöissä on monin paikoin kehitettävää lasten ja nuorten osallistumista tukevan toimintakulttuurin saavuttamisessa. Osallistumista voidaan edistää johtamisella tunnistamalla ja sanoittamalla sen merkitystä, kehittämällä osallistumisen menetelmiä ja tukemalla osallistumisen kulttuuria

    Endocannabinoid Signaling in Embryonic Neuronal Motility and Cell-Cell Contact - Role of mGluR5 and TRPC3 Channels

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    Cell-cell communication plays a central role in the guidance of migrating neuronal precursor cells during the development of the cerebral cortex. Endocannabinoids (eCBs) have previously been shown to be one of the central factors regulating neuronal migration. In this study the effects of eCBs on different parameters, expected to affect embryonic cortical neuronal motility have been analyzed in neurosphere-derived neuroblasts using time-lapse microscopy. Increased endogenous production of the endocannabinoid 2-arachidonyl glycerol (2-AG) causes bursts of neuroblast motility. The neuroblasts move longer distances and show a low frequency of turning, and the number of neuron-neuron contacts are reduced. Similar changes occur interfering with the function of the metabotropic glutamate receptor 5 (mGluR5) or its transducer canonical transient receptor potential channel 3 (TRPC3) or the neuregulin receptor ErbB4. Blocking of 2-AG production reverses these effects. The data suggest that eCB-regulated neuronal motility is controlled by mGluR5/TRPC3 activity possibly via NRG/ErbB4 signaling. (C) 2018 IBRO. Published by Elsevier Ltd. All rights reserved.Peer reviewe

    Full-Duplex OFDM Radar With LTE and 5G NR Waveforms: Challenges, Solutions, and Measurements

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    This paper studies the processing principles, implementation challenges, and performance of OFDM-based radars, with particular focus on the fourth-generation Long-Term Evolution (LTE) and fifth-generation (5G) New Radio (NR) mobile networks' base stations and their utilization for radar/sensing purposes. First, we address the problem stemming from the unused subcarriers within the LTE and NR transmit signal passbands, and their impact on frequency-domain radar processing. Particularly, we formulate and adopt a computationally efficient interpolation approach to mitigate the effects of such empty subcarriers in the radar processing. We evaluate the target detection and the corresponding range and velocity estimation performance through computer simulations, and show that high-quality target detection as well as high-precision range and velocity estimation can be achieved. Especially 5G NR waveforms, through their impressive channel bandwidths and configurable subcarrier spacing, are shown to provide very good radar/sensing performance. Then, a fundamental implementation challenge of transmitter-receiver (TX-RX) isolation in OFDM radars is addressed, with specific emphasis on shared-antenna cases, where the TX-RX isolation challenges are the largest. It is confirmed that from the OFDM radar processing perspective, limited TX-RX isolation is primarily a concern in detection of static targets while moving targets are inherently more robust to transmitter self-interference. Properly tailored analog/RF and digital self-interference cancellation solutions for OFDM radars are also described and implemented, and shown through RF measurements to be key technical ingredients for practical deployments, particularly from static and slowly moving targets' point of view.Comment: Paper accepted by IEEE Transactions on Microwave Theory and Technique

    Regulation of radial glial process growth by glutamate via mGluR5/TRPC3 and neuregulin/ErbB4

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    Radial glial cells play an essential role through their function as guides for neuronal migration during development. Disruption of metabotropic glutamate receptor 5 (mGluR5) function retards the growth of radial glial processes in vitro. Neuregulins (NRG) are activated by proteolytic cleavage and regulate (radial) glial maintenance via ErbB3/ErbB4 receptors. We show here that blocking ErbB4 disrupts radial process extension. Soluble NRG acting on ErbB4 receptors is able to promote radial process extension in particular where process elongation has been impeded by blockade of mGluR5, the nonselective cation channel canonical transient receptor potential 3 (TRPC3), or matrix metalloproteases (MMP). NRG does not restore retarded process growth caused by ErbB4 blockade. Stimulation of muscarinic receptors restores process elongation due to mGluR5 blockade but not that caused by TRPC3, MMP or ErbB4 blockade suggesting that muscarinic receptors can replace mGluR5 with respect to radial process extension. Additionally, NRG/ErbB4 causes Ca2+ mobilization in a population of cells through cooperation with ErbB1 receptors. Our results indicate that mGluR5 promotes radial process growth via NRG activation by a mechanism involving TRPC3 channels and MMPs. Thus neurotransmitters acting on G-protein coupled receptors could play a central role in the maintenance of the radial glial scaffold through activation of NRG/ErbB4 signaling.Peer reviewe

    Air-Induced PIM Cancellation in FDD MIMO Transceivers

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    In this letter, air-induced passive intermodulation (PIM) modeling and cancellation schemes are presented in a multiple-input multiple-output (MIMO) frequency-division duplexing (FDD) transceiver context. PIM is distortion generated by nonlinear passive devices either within the transmitter chain or outside the transceiver system, as is the case in air-induced PIM. In FDD systems, the PIM products may lie on the receiver band, thus possibly desensitizing the receiver chain. Unlike previous PIM cancellation works, we consider a challenging rank-2 dual-carrier MIMO transceiver scenario, with two spatially multiplexed signals per component carrier (CC). Stemming from the PIM modeling, we first present a cancellation method based on a complete set of identified basis functions (BFs). Additionally, to relax the processing complexity, we propose an alternative canceller solution with a reduced number of BFs, inspired by the problem modeling. RF measurements conducted with real-life equipment indicate favorable PIM suppression levels of up to 20 dB using both introduced techniques.publishedVersionPeer reviewe

    Air-Induced Passive Intermodulation in FDD MIMO Systems : Algorithms and Measurements

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    In this article, we model and develop effective cancellation schemes for passive intermodulation (PIM) distortion induced by external objects in the vicinity of the transmitter—referred to as air-induced PIM—in frequency-division duplex (FDD) multiple-input–multiple-output (MIMO) systems. PIM is interference generated from the transmitted signals undergoing nonlinear transformation, which, in FDD systems, may cause desensitization of the receiver chain. First, we present a general model of the received air-induced PIM signal, with an arbitrary number of dual-carrier TX chains active and an arbitrary number of PIM sources causing interference, on all the intermodulation frequencies. Then, the derived model is used to develop a cancellation scheme based on a complete set of basis functions (BFs) in a rank-2 dual-carrier MIMO system with four active carriers. To alleviate the high complexity of the aforementioned scheme, we then propose a novel alternative cancellation scheme with much reduced complexity, leveraging on the physical modeling of the system, which is capable of handling any number of PIM sources in the system. RF measurement-based experimentations carried out with real-life equipment evidence excellent cancellation capabilities of the complete BF model, which can be retained with much reduced complexity with the proposed alternative technique.publishedVersionPeer reviewe

    Cellular Digital Post-Distortion : Signal Processing Methods and RF Measurements

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    In this paper, we study the feasibility of digital post-distortion (DPoD) based mitigation of transmitter nonlinear distortion in cellular networks. With specific emphasis on downlink, we describe a computationally efficient one-shot method to estimate and mitigate the cascaded multipath channel and transmitter nonlinear distortion effects at terminal receiver, building on demodulation reference symbols (DMRSs). We also describe a DMRS boosting approach to match the envelope characteristics of the DMRS and the actual data-bearing multicarrier symbols such that accurate mitigation is feasible. We provide RF measurement results with a state-of-the-art 28 GHz active antenna array and 256-QAM data modulation, demonstrating larger performance enhancements in received signal error vector magnitude (EVM) compared to existing computationally expensive iterative methods.Peer reviewe
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