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Mercury in immature and adults Herring Gulls (Larus argentatus) wintering on the Gulf of Gdańsk area

Szumiło E., Szubska M., Meissner W., Bełdowska M., Falkowska L.

Oceanological and Hydrobiological Studies

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2013

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Vol. 42, No. 3

260--267

EN

This study presents total mercury concentrations (HgT) in selected tissues and organs (blood, muscles, liver, kidneys, feathers and claws) of the herring gull (Larus argentatus) in order to assess the environmental pollution in the coastal zone of the southern Baltic. Dead, frozen birds were collected in the vicinity of Wladysławowo between December 2009 and March 2010, an exceptionally severe winter — a total of 13 specimens; 6 adults (>4 years old) and 7 immature birds (≤4 years old). Mercury concentrations in all analyzed samples exceeded the detection limit. The lowest average concentration, at a level of 0.4 μg Hg g−1 (d.w.) was observed in the muscles of adult and immature gulls while the highest, at a level of 3.3 μg Hg g−1 (d.w), was determined in the contour of immature gulls. A significant linear correlation was found between mercury concentration in the blood and the concentration in the kidneys and liver, with the coefficients of determination at R2 = 0.87 and 0.86, respectively. This indicates that blood of birds, as a mercury carrier, may reflects the concentration of mercury in tissues and internal organs of birds and, in the case of kidneys and liver, may express long-term exposure to mercury in nourishment.

2

Modelowanie narządów wewnętrznych człowieka za pomocą wielościanów na potrzeby systemu treningowego dla robota chirurgicznego ROCH-1

Leniowski R., Zima M., Jurkowski S.

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2012

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z. 182, t. 1

115--127

PL

Modele matematyczne miękkich tkanek spełniają istotną role w wirtualnych narzędziach treningowych stosowanych w chirurgii małoinwazyjnej. Umożliwiają one modelowanie i symulację zjawisk zachodzących podczas rzeczywistej operacji tkanką. W pracy zaproponowano oryginalną koncepcję modelowania narządów wewnętrznych człowieka w oparciu o elementarny model składowy o zredukowanej dynamice, który ma kształt wielościanu. Zastosowany model masa – sprężyna – tłumik (MSD) tworzy strukturę bryłową, ma własności lepko-sprężyste, zbliżone do tkanki biologicznej i reaguje prawidłowo na oddziaływania zewnętrzne, powodujące deformację elementu. Wielościan, nazywany dalej „kostką”, można dopasować do rozpatrywanego narządu człowieka poprzez modyfikację jego parametrów. „Kostkę” charakteryzuje ponadto łatwa implementacja programowa, dzięki czemu model fizyczny połączono z modelem graficznym, uzyskując wirtualne narządy (jelito grube, serce, nerkę), o bardzo realistycznych właściwościach. Istotne jest również to, że bieżąca implementacja modelu uwzględniania oddziaływania grawitacyjne oraz ciśnienia: wewnętrzne i zewnętrzne, występujące w warunkach rzeczywistych. Opracowany model wykorzystano do wytworzenia wirtualnej postaci jelita grubego, które poddano prostym i złożonym deformacjom. Jelito grube jest częścią składową systemu treningowego, opracowanego dla prowadzenia wirtualnych zabiegów (treningów) z użyciem robota chirurgicznego ROCH-1.

EN

Mathematical models of soft tissues play an important role in virtual simulation of surgical robots. The paper described an original adaptation of the reduced model of a polyhedron, which is very well suited for modeling of human organs (soft tissue). The proposed model MSD (mass-spring-damper) creates a solid structure which has viscoelastic properties similar to biological tissue. The elementary polyhedron, called the “cube”, can be tuned, depending on the type of human organs in question, by modifying the material parameters. Moreover, the “cube” is characterized be easy implementation of the program, so that the physical model is combined with a graphical model, to yield organs behaving very realistic. It should be noted that the current implementation of the model takes into account: gravitation, internal and external pressure and forces that occur in real terms. The example shows the complex deformations of the large intestine. This organ is part of the simulator software, developed for conducting virtual operations using a surgical robot ROCH-1.

3

Mercury distribution in muscles and internal organs of the juvenile and adult Baltic cod (Gadus morrhua callarias Linnaeus, 1758)

Kwaśniak J., Falkowska L.

Oceanological and Hydrobiological Studies

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2012

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Vol. 41, No. 2

65-71

EN

Cod (Gadus marrhua L), a fish caught in the Baltic Sea, is very popular with consumers. Research on the distribution of mercury in cod tissues and organs was conducted on a group of adult (27) and juvenile (49) individuals in the years 2006-09. Total mercury concentration values in mature cod were always, on average, 1.7 times higher than those in juveniles. The highest HgT concentrations were found in the heart, while the lowest ones were found in the gills and gonads. The essential age-specific differences manifest in a relationship between the mercury concentration in fish muscles and brain. Mature individuals, i.e. of length >80 cm, accumulated Hg in muscles, most likely in an attempt to protect the nervous system from toxic exposure. In young individuals, more mercury was concentrated in the brain than in the muscles.. The distribution of HgT in organs as well as the low value of the [HgT]liver/[HgT]muscle ratio testify to relatively low-level mercury contamination in southern Baltic waters.

4

Modelling objects with changing shapes : a survey

Baldassarri S., Gutierrez Perez D., Seron Arbeloa F.

Machine Graphics and Vision

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2002

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Vol. 11, No. 4

399-430

EN

The great number of object modelling computer techniques that alresdy exist and the new ones that are continuously appearing are the result of a multidisciplinary exchange of ideas. Within this area, objects with changing shapes are inherently more difficult to model than rigid objects. Our main goal has been to provide a classification of the algorithms involved in the modelling of objects that can be as diverse as water, clothes, faces,...The classification has been made from the starting poing of inorganic and organic categories. Inorganic objects are classified according to their material state while the organic ones are classified according to the realm they belong to. Within each category, works are generally presented in chronological order, providing an extensive bibliography.