40 research outputs found

    Environmental factors shaping the distribution of common wintering waterbirds in a lake ecosystem with developed shoreline

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    In this study, we tested whether the spatial distribution of waterbirds is influenced by shoreline urbanization or other habitat characteristics. We conducted monthly censuses along shoreline sections of a continental lake (Lake Balaton, Hungary) to assess the abundance of 11 common species that use this lake as a feeding and staging area during migration and winter. We estimated the degree of urbanization of the same shoreline sections and also measured other habitat characteristics (water depth, extent of reed cover, biomass of zebra mussels, distances to waste dumps and to other wetlands). We applied linear models and model averaging to identify habitat variables with high relative importance for predicting bird distributions. Bird abundance and urbanization were strongly related only in one species. Other habitat variables exhibited stronger relationships with bird distribution: (1) diving ducks and coots preferred shoreline sections with high zebra mussel biomass, (2) gulls preferred sites close to waste dumps, and (3) the abundances of several species were higher on shoreline sections close to other wetlands. Our findings suggest that the distribution of waterbirds on Lake Balaton is largely independent of shoreline urbanization and influenced by food availability and connectivity between wetlands

    Low dose cranial irradiation-induced cerebrovascular damage is reversible in mice

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    BACKGROUND: High-dose radiation-induced blood-brain barrier breakdown contributes to acute radiation toxicity syndrome and delayed brain injury, but there are few data on the effects of low dose cranial irradiation. Our goal was to measure blood-brain barrier changes after low (0.1 Gy), moderate (2 Gy) and high (10 Gy) dose irradiation under in vivo and in vitro conditions. METHODOLOGY: Cranial irradiation was performed on 10-day-old and 10-week-old mice. Blood-brain barrier permeability for Evans blue, body weight and number of peripheral mononuclear and circulating endothelial progenitor cells were evaluated 1, 4 and 26 weeks postirradiation. Barrier properties of primary mouse brain endothelial cells co-cultured with glial cells were determined by measurement of resistance and permeability for marker molecules and staining for interendothelial junctions. Endothelial senescence was determined by senescence associated β-galactosidase staining. PRINCIPLE FINDINGS: Extravasation of Evans blue increased in cerebrum and cerebellum in adult mice 1 week and in infant mice 4 weeks postirradiation at all treatment doses. Head irradiation with 10 Gy decreased body weight. The number of circulating endothelial progenitor cells in blood was decreased 1 day after irradiation with 0.1 and 2 Gy. Increase in the permeability of cultured brain endothelial monolayers for fluorescein and albumin was time- and radiation dose dependent and accompanied by changes in junctional immunostaining for claudin-5, ZO-1 and β-catenin. The number of cultured brain endothelial and glial cells decreased from third day of postirradiation and senescence in endothelial cells increased at 2 and 10 Gy. CONCLUSION: Not only high but low and moderate doses of cranial irradiation increase permeability of cerebral vessels in mice, but this effect is reversible by 6 months. In-vitro experiments suggest that irradiation changes junctional morphology, decreases cell number and causes senescence in brain endothelial cells

    Abstracts from the 20th International Symposium on Signal Transduction at the Blood-Brain Barriers

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    https://deepblue.lib.umich.edu/bitstream/2027.42/138963/1/12987_2017_Article_71.pd

    Robin Heart INCITE – telemanipulator chirurgiczny sterowany przez system wyposażony w czujnik siły 3D

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    The aim of this work is to present the final report, financed by the EU INCITE grant, development of the robot control system Robin Heart with the use of special 3D MEMS micro-sensors, to verify their following functions: 1) an easy control of robotic movement during operation using a micro joystick integrated with the laparoscopic tool 2) measuring the value and direction of force between the jaw of the laparoscopic tool and operated organ 3) tissue diagnostics during work using a 3D touch sensor placed in the front of the tool. Piezo-resistive silicon sensors have been designed and manufactured by the Hungarian company EK MFA. A prototype of a miniature motion sensor placed on the gripping part of the endoscopic tool to control the vision path robot was made. Sensory endoscopic tools were integrated with the ROBIN HEART robot and the Robin Hand motion unit as well as innovative mechatronic surgical tools with a panel informing about the measurement values of the force of tools and tissue. Researched prototype sensors have demonstrated their usefulness in the robot's force feedback system. The practicality of the application to assess the condition of the tissue and the strength of the endoscopic grasper clamp was confirmed. The work was carried out as a part of the EU INCITE project financed partly by NCBiR and NKFIA.Celem pracy jest przedstawienie finalnego raportu finansowanego z projektu EU INCITE rozwoju projektu systemu sterowania robota Robin Heart z zastosowaniem specjalnych mikro-czujników 3D MEMS, dla weryfikacji ich następujących funkcji: 1) sterowanie robotem toru endoskopowego za pomocą mikro-dżojstika zintegrowanego z rękojeścią narzędzia laparoskopowego dla ergonomicznej manipulacji. 2) pomiar wartości i kierunku działania siły pomiędzy szczęką narzędzia laparoskopowego, a organem. 3) diagnostyki tkanek podczas pracy za pomocą czujnika dotykowego 3D umieszczonego w czołowej części narzędzia. Piezorezystancyjne sensory krzemowe zostały zaprojektowane i wykonane przez węgierską firmę EK MFA. Wykonany został prototyp miniaturowego zadajnika ruchu umieszczonego na części chwytowej narzędzia endoskopowego do sterowania robotem toru wizyjnego. Wykonano sensoryczne narzędzia endoskopowe zintegrowane z robotem ROBIN HEART i zadajnikiem ruchu Robin Hand oraz nowatorskie mechatroniczne narzędzia chirurgiczne z panelem informującym o wartości pomiarów siły oddziaływania narzędzi z tkanką. Zrealizowane badania prototypowych czujników wykazały ich użyteczność w układzie siłowego sprzężenia zwrotnego robota. Potwierdzono celowość aplikacji do oceny stanu tkanki i siły zacisku graspera endoskopowego. Praca została wykonana w ramach projektu EU INCITE finansowana częściowo przez NCBiR i NKFIA

    Robin Heart INCITE - application of haptic feedback to surgical telemanipulator

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    Celem pracy jest przedstawienie rozwoju projektu systemu sterowania robota Robin Heart z zastosowaniem specjalnych mikro--czujników 3D MEMS, dla weryfikacji ich następujących funkcji: 1) sterowanie robotem toru endoskopowego za pomocą mikro--dżojstika zintegrowanego z rękojeścią narzędzia laparoskopowego dla ergonomicznej manipulacji. 2) pomiar wartości i kierunku działania siły pomiędzy szczęką narzędzia laparoskopowego, a organem. 3) diagnostyki tkanek podczas pracy za pomocą czujnika dotykowego 3D umieszczonego w czołowej części narzędzia. Piezorezystancyjne sensory krzemowe zostały zaprojektowane i wykonane przez węgierską firmę EK MFA. Przeprowadzone zostały symulacje MES w celu określenia podstawowych parametrów mechanicznych czujnika. Czujniki zostały pokryte polimerem półprzewodnikowym PDMS (polidimetylosiloksan), następnie przeprowadzono badania wpływu powłoki elastycznej pod kątem czułości i czasu odpowiedzi. Zgodnie z wymaganiami medycznymi i funkcjonalnymi czujniki dodatkowo zostały pokryte biokompatybilnym elastycznym polimerem. Wykonany został prototyp miniaturowego zadajnika ruchu umieszczonego na części chwytowej narzędzia laparoskopowego. Przeprowadzone zostały testy polegające na orientacji robota w polu operacyjnym za pomocą trójosiowego czujnika siły. Przeprowadzono wstępne testy sensorycznego narzędzia laparoskopowego zintegrowanego z robotem ROBIN HEART i zadajnikiem ruchu Robin Hand. Zrealizowane badania prototypowych czujników wykazały ich użyteczność w układzie siłowego sprzężenia zwrotnego robota. Potwierdzono celowość aplikacji do oceny stanu tkanki i siły zacisku graspera laparoskopowego. Praca została wykonana w ramach projektu EU INCITE finansowana częściowo przez NCBiR.The aim of this work is to demonstrate the applicability and functionality of the Robin Heart robot's control systems integrated with special MEMS based 3D force micro-sensors. Three different robot functions and corresponding detector devices are proposed: 1) Micro-joystick type actuator to be integrated in the hilt of the laparoscope to control easily robotic movement during operation. 2) 1D force sensor located inside the laparoscopic jaw to provide feedback to the surgeon by measuring the grasping strength and 3) 3D (vectorial) force/tactile sensor placed at the tip of the laparoscope which facilitates palpation for tissue diagnostics during operation. The silicon based piezoresistive sensors have been designed and prepared by micromachining technologies in the MEMS Laboratory of EK MFA (Budapest, Hungary). According to the medical and functional requirements the sensors were electro-mechanically integrated and covered by biocompatible elastic polymer (polydimethylsiloxane – PDMS) by BME (Budapest, Hungary). The device geometry was modelled by coupled finite element simulation to determine its expected performance. The effect of the elastic coverage was studied in terms of sensitivity and response time also. Preliminary test of the laparoscopic head equipped with MEMS sensors and integrated in the ROBIN HEART surgery robot system was performed by FRK (Zabrze, Poland). A model of the robot controller using a prototype of 3D force sensor has been also successfully tested during the tests of the functional robot. Studies of the prototypes of “smart” sensory laparoscopes have demonstrated their remarkable usefulness in force feedback robotic systems to recognize the state of tissue and to determine the clamping force of the grasper of surgical system. The international cooperation to develop “smart” laparoscope for robotic surgery was done in the frame of the ENIAC “INCITE” project No.621278 and partially financed by the ENIAC JU and the National Centre for Research and Development (NCBR - Poland) and National Research, Development and Innovation Fund (NKFIA – Hungary)
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