Design of a Virtual Player for Joint Improvisation with Humans in the Mirror Game

Joint improvisation is often observed among humans performing joint action tasks. Exploring the underlying cognitive and neural mechanisms behind the emergence of joint improvisation is an open research challenge. This paper investigates jointly improvised movements between two participants in the mirror game, a paradigmatic joint task example. First, experiments involving movement coordination of different dyads of human players are performed in order to build a human benchmark. No designation of leader and follower is given beforehand. We find that joint improvisation is characterized by the lack of a leader and high levels of movement synchronization. Then, a theoretical model is proposed to capture some features of their interaction, and a set of experiments is carried out to test and validate the model ability to reproduce the experimental observations. Furthermore, the model is used to drive a computer avatar able to successfully improvise joint motion with a human participant in real time. Finally, a convergence analysis of the proposed model is carried out to confirm its ability to reproduce joint movements between the participants.This work was supported by European Project AlterEgo FP7 ICT 2.9 - Cognitive 321 Sciences and Robotics, Grant Number 600610 (MdB, http://www.euromov.eu/alterego/project)

Dynamic similarity promotes interpersonal coordination in joint-action

Human movement has been studied for decades and dynamic laws of motion that are common to all humans have been derived. Yet, every individual moves differently from everyone else (faster/slower, harder/smoother etc). We propose here an index of such variability, namely an individual motor signature (IMS) able to capture the subtle differences in the way each of us moves. We show that the IMS of a person is time-invariant and that it significantly differs from those of other individuals. This allows us to quantify the dynamic similarity, a measure of rapport between dynamics of different individuals' movements, and demonstrate that it facilitates coordination during interaction. We use our measure to confirm a key prediction of the theory of similarity that coordination between two individuals performing a joint-action task is higher if their motions share similar dynamic features. Furthermore, we use a virtual avatar driven by an interactive cognitive architecture based on feedback control theory to explore the effects of different kinematic features of the avatar motion on the coordination with human players

Internal carotid artery perforation during the surgical treatment of a heamodynamically significant and symptomatic kinking — a case report

Powszechnie uważa się, że wskazaniem do leczenia operacyjnego wydłużenia tętnicy szyjnej wewnętrznej jest jej istotne hemodynamicznie objawowe zagięcie kątowe. Bezpieczeństwo i korzyści leczenia operacyjnego tych wad są porównywalne do operacji udrożnienia tętnic szyjnych z powodu zmian miażdżycowych. W pracy przedstawiono przypadek korekcji wady tętnicy szyjnej wewnętrznej u pacjenta, u którego występowała nietolerancja na przerwanie przepływu przez tętnice podczas jej zaciśnięcia. Podczas próby założenia czasowego przepływu doszło do przedziurawienia tętnicy szyjnej wewnętrznej w „niewygodnym” technicznie miejscu, co zmusiło operatorów do zmiany planowanego zabiegu. Operacja zakończyła się powodzeniem.It is widely accepted that surgery is the treatment of choice for a symptomatic and haemodynamically significant carotid artery kinking. The safety and benefit of surgical correction of these lesions is comparable to the surgical treatment of carotid atherosclerotic lesions. In this paper, authors present a case report of a patient undergoing surgical treatment of carotid kinking with a complete intolerance to carotid clamping (resulting in insufficient cerebral blood flow). During the insertion of a carotid shunt, a perforation of the internal carotid artery occurred in a very difficult site, leading to rapid change of surgical procedure. The operation ended with a complete success

Assessment of serpulid-hydroid association through the Jurassic : a case study from the Polish Basin

The coexistence of sessile, tube-dwelling polychaetes (serpulids) and hydroids, has been investigated. Serpulid tubes bearing traces after hydroids are derived from different stratigraphic intervals spanning the Middle and Upper Jurassic, the rocks of which represent the diverse paleoenvironments of the Polish Basin. Although fossil colonial hydroids classified under the species Protulophila gestroi are a commonly occurring symbiont of these polychaetes during the Late Cretaceous and Cenozoic, they seem to be significantly less frequent during the Jurassic and limited to specific paleoenvironments. The hydroids described here are represented by traces after a thin stolonal network with elongated polyp chambers that open to the outer polychaete tube’s surface with small, more or less subcircular apertures. Small chimney-like bulges around openings are an effect of the incorporation of the organism by in vivo embedment (bioclaustration) within the outer layers of the calcareous tube of the serpulid host. Considering the rich collection of well-preserved serpulid tubes (>3000 specimens), the frequency of bioclaustrated hydroids is very low, with an infestation percentage of only 0.6% (20 cases). It has been noticed that only specimens of the genus Propomatoceros from the Upper Bajocian, Lower Bathonian, Middle Bathonian, and Callovian have been found infested. However, the majority of bioclaustrated hydroids (17 cases) have been recorded in the Middle Bathonian serpulid species Propomatoceros lumbricalis coming from a single sampled site. Representatives of other genera are not affected, which is congruent with previous reports indicating that Protulophila gestroi was strongly selective in the choice of its host. A presumably commensal relationship is compared with the recent symbiosis between the hydroids of the genus Proboscidactyla and certain genera of sabellid polychaetes

Ocena aktywności płytek krwi i częstości występowania oporności na przeciwpłytkowe działanie kwasu acetylosalicylowego w prewencji zakrzepowej chorych po endarterektomii tętnic szyjnych

Background. Low-dose acetylsalicylic acid represents standard antiplatelet therapy in patients after surgicalor endovascular treatment of atherosclerotic carotid artery stenosis. However, almost 8% of these patientsexperience restenosis in the same vessel within a year of the procedure, irrespective of the applied techniqueor its potential complications. Many authors suggest that complications can be related to a lack of the expectedeffect of antiplatelet agents.Aims: 1) evaluation of platelet activity and incidence of resistance to acetylsalicylic acid (ASA) in thrombosisprevention after carotid endarterectomy; 2) determination of risk factors for resistance to acetylsalicylic acid(aspirin resistance).Material and methods. The study group included 66 patients operated on due to significant stenosis ofcarotid arteries (70–99%). The group consisted of 27 women and 39 men, aged 41–80 years.Patients were administered 75 mg of acetylsalicylic acid daily both before and after operation. Platelet activitywas measured 10 days after operation, using a PFA-100 analyser. The results were classified as normalresponse to ASA or resistance to the drug.Results. Nineteen patients (32%) developed resistance to ASA after operation. Arterial hypertension, treatmentwith other non-steroid anti-inflammatory agents, and advanced atherosclerosis of lower limb arterieswere major risk factors of resistance to ASA in multivariate logit regression analysis model.Conclusions. 1) Incidence of resistance to anti-aggregatory effect of ASA in patients who underwent surgicalinterventions for atherosclerotic stenosis of carotid arteries is high, which may mean that no effective antiplatelettherapy is available for these patients. 2) Advanced atherosclerotic lesions, arterial hypertension, and treatmentwith non-steroid anti-inflammatory drugs are risk factors of resistance to ASA. 3) Routine assessmentof resistance to ASA by the bedside may be justified in patients having the above-mentioned risk factors.Wstęp. Leczenie przeciwpłytkowe małymi dawkami kwasu acetylosalicylowego (ASA) to rutynowe postępowanieu pacjentów leczonych operacyjnie i endowaskularnie z powodu miażdżycowego zwężenia tętnic szyjnych.Mimo to u około 8% pacjentów w ciągu roku dochodzi do wtórnej niedrożności operowanego naczynia niezależnieod stosowanej metody lub problemów technicznych w czasie zabiegu. Wielu autorów uważa, że częśćpowikłań może być spowodowana brakiem oczekiwanej reakcji na leki antyagregacyjne.Cele pracy: 1) ocena aktywności płytek krwi i częstości występowania oporności na przeciwpłytkowe działanieASA w prewencji zakrzepowej chorych po endarterektomii tętnic szyjnych; 2) ustalenie czynników determinującychwystępowanie oporności na przeciwpłytkowe działanie kwasu acetylosalicylowego (aspirynooporności).Materiał i metody. Badaniami objęto 66 chorych operowanych z powodu objawowego zwężenia tętnic szyjnych(70–99%). Operowano 27 kobiet oraz 39 mężczyzn w wieku 41–80 lat.Pacjenci w okresie przed- i pooperacyjnym przyjmowali ASA w dawce 75 mg/d. Pomiary reaktywności płytekwykonano przy użyciu analizatora funkcji płytek krwi PFA-100 w 10. dobie po operacji. Pacjentów podzielonona grupę prawidłowo reagujących na ASA oraz na aspirynoopornych.Wyniki. W przebiegu pooperacyjnym oporność na ASA wykazano u 19 pacjentów (32%). W modelu wieloczynnikowejanalizy regresji logitowej niezależnym czynnikiem ryzyka wystąpienia aspirynooporności byłynadciśnienie tętnicze, przyjmowanie innych niesteroidowych leków przeciwzapalnych oraz zaawansowanamiażdżyca kończyn dolnych.Wnioski. 1. Częstość zjawiska oporności na przeciwagregacyjne działanie ASA u pacjentów leczonych operacyjniez powodu miażdżycowego zwężenia tętnic szyjnych jest wysoka, co wskazuje na możliwość istnieniabraku skutecznej terapii przeciwpłytkowej. 2. Zaawansowana miażdżyca, nadciśnienie tętnicze, przyjmowanieniesteroidowych leków przeciwzapalnych to czynniki ryzyka mogące mieć wpływ na ryzyko wystąpienia aspirynooporności.3. Rutynowe, „przyłóżkowe” badanie oporności biochemicznej na ASA może być uzasadnioneu pacjentów z wyżej wymienionymi czynnikami ryzyka aspirynooporności

Neodymium isotopes in peat reveal past local environmental disturbances

Funding The Stawek profile radiocarbon dating and investigation and neodymium measurements were financed by the National Science Centre, Poland, grants no. 2019/03/X/ST10/00849 and 2020/39/D/ST10/00641. The Głęboczek profile radiocarbon dating and investigation were financed by the National Science Centre, Poland, grant no. 2015/17/B/ST10/01656.Peer reviewedPublisher PD

Hydrological dynamics and fire history of the last 1300years in western Siberia reconstructed from a high-resolution, ombrotrophic peat archive

International audienceSiberian peatlands provide records of past changes in the continental climate of Eurasia. We analyzed a core from Mukhrino mire in western Siberia to reconstruct environmental change in this region over the last 1300 years. The pollen analysis revealed little variation of local pine-birch forests. A testate amoebae transfer function was used to generate a quantitative water-table reconstruction; pollen, plant macrofossils, and charcoal were analyzed to reconstruct changes in vegetation and fire activity. The study revealed that Mukhrino mire was wet until the Little Ice Age (LIA), when drought was recorded. Dry conditions during the LIA are consistent with other studies from central and eastern Europe, and with the pattern of carbon accumulation across the Northern Hemisphere. A significant increase in fire activity between ca. AD 1975 and 1990 may be associated with the development of the nearby city of Khanty-Mansiysk, as well as with the prevailing positive Arctic Oscillation

Znaczenie wysokorozdzielczych wielowskaźnikowych (multi-proxy) badań paleoekologicznych dla geografii historycznej i historii gospodarczej

The article presents the importance of palaeoecology for the study of economic history, historical geography and environmental history. The text introduces the methodological possibilities of palaeoecology. We pay attention to the unused potential of high resolution palaeoecology. By using natural archives (sediments of lakes and peatlands), we are able to trace the history of changes in nature. We can reconstruct history and better understand the changes in Poland’s ecosystems and its economic development.Artykuł prezentuje znaczenie paleoekologii dla badań historii gospodarczej, geografii historycznej i historii środowiskowej. Praca przybliża możliwości metodyczne paleoekologii. Zwracamy uwagę na niewykorzystany dotąd potencjał wysokorozdzielczej paleoekologii. Wykorzystując naturalne archiwa (osady jezior i torfowisk), jesteśmy w stanie prześledzić historię przemian przyrody, możemy zrekonstruować historię i lepiej zrozumieć zmiany ekosystemów Polski oraz jej rozwój ekonomiczny

Gaze training supports self-organization of movement coordination in children with developmental coordination disorder

Children with developmental coordination disorder (DCD) struggle with the acquisition of coordinated motor skills. This paper adopts a dynamical systems perspective to assess how individual coordination solutions might emerge following an intervention that trained accurate gaze control in a throw and catch task. Kinematic data were collected from six upper body sensors from twenty-one children with DCD, using a 3D motion analysis system, before and after a 4-week training intervention. Covariance matrices between kinematic measures were computed and distances between pairs of covariance matrices calculated using Riemannian geometry. Multidimensional scaling was then used to analyse differences between coordination patterns. The gaze trained group revealed significantly higher total coordination (sum of all the pairwise covariances) following training than a technique-trained control group. While the increase in total coordination also significantly predicted improvement in task performance, the distinct post-intervention coordination patterns for the gaze trained group were not consistent. Additionally, the gaze trained group revealed individual coordination patterns for successful catch attempts that were different from all the coordination patterns before training, whereas the control group did not. Taken together, the results of this interdisciplinary study illustrate how gaze training may encourage the emergence of coordination via self-organization in children with DCD