PCDD, PCDF, PCB and thiamine in Baltic herring (Clupea harengus L.) and sprat [Sprattus sprattus (L.)] as a background to the M74 syndrome of Baltic salmon (Salmo salar L.)   总被引：1，自引：0，他引：1  

Vuorinen  Pekka J.; Parmanne  Raimo; Vartiainen  Terttu; Keinanen  Marja; Kiviranta  Hannu; Kotovuori  Olli; Halling  Folke 《ICES Journal of Marine Science》2002,59(3):480-496

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Factors affecting rule compliance with mesh size regulations in the Baltic cod trawl fishery   总被引：1，自引：0，他引：1  

Suuronen  Petri; Tschernij  Vesa; Jounela  Pekka; Valentinsson  Daniel; Larsson  P-O. 《ICES Journal of Marine Science》2007,64(8):1603-1606

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How to Earn the Status of Honest Broker? Scientists’ Roles Facilitating the Political Water Supply Decision-Making Process     

Lauri Rantala  Simo Sarkki  Timo P. Karjalainen  Pekka M. Rossi 《社会与自然资源》2017,30(10):1288-1298

“Honest broker” refers to scientists facilitating complex political decisions from a neutral position, aiming to expand the scope of choice available instead of advocating a certain policy. This article reflects on the experiences of three scientists acting as honest brokers while carrying out a multicriteria evaluation to help politicians choose the water supply option for the city of Oulu, Finland. The process was considered successful and many politicians said that they have never before been that well informed when making a decision. The case primarily shows that besides the common knowledge brokerage roles targeting knowledge exchange, the honest brokerage approach relates more to managing social relationships and balancing political games and rapidly evolving discussions. Trustful relationships increased the perceived credibility of the brokers and ensured two-way communication. On the other hand, the brokers faced ethical dilemmas and difficulties of staying impartial while finding out confidential information related to political strategies.  相似文献   

Range and AGC normalization in airborne discrete-return LiDAR intensity data for forest canopies   总被引：1，自引：0，他引：1  

Ilkka Korpela  Hans Ole Ørka  Juha Hyyppä  Ville Heikkinen  Timo Tokola 《ISPRS Journal of Photogrammetry and Remote Sensing》2010,65(4):369-379

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Biomarker responses as indication of contaminant effects in blue mussel (Mytilus edulis) and female eelpout (Zoarces viviparus) from the southwestern Baltic Sea   总被引：1，自引：0，他引：1  

Schiedek D  Broeg K  Barsiene J  Lehtonen KK  Gercken J  Pfeifer S  Vuontisjärvi H  Vuorinen PJ  Dedonyte V  Koehler A  Balk L  Schneider R 《Marine pollution bulletin》2006,53(8-9):387-405

During a field study performed in spring and autumn 2001 and 2002, blue mussels (Mytilus edulis) and female eelpout (Zoarces viviparus) were collected at three locations in the Wismar Bay (Baltic Sea), and several biomarkers of contaminant effects were analysed. Besides seasonal and inter-annual variations, biomarker signals were most pronounced at the location closest to Wismar Harbour (Wendorf) in both species. Lysosomal membrane stability (LMS) was lowest and acetylcholinesterase activity (AChE) was significantly reduced. Frequency of micronuclei (MN) was significantly higher (in blue mussels), indicating mutagenic effects. In eelpout elevated levels of DNA adducts, EROD induction and PAH-metabolites were measured. Metallothionein (MT), biomarker for trace metal exposure, showed a gradient only in spring. Organochlorine contaminant analyses (PCBs, DDTs) corresponded to the observed biomarker levels. The results obtained clearly demonstrate pollution effects in the southwestern Baltic Sea. Moreover, they show that a multibiomarker approach is also applicable in a brackish water environment.  相似文献   

Lithostratigraphy and Optically Stimulated Luminescence age determinations of pre‐Late Weichselian deposits in the Suupohja area,western Finland     

Reijo Pitkäranta  Juha‐Pekka Lunkka  Kari O. Eskola 《Boreas: An International Journal of Quaternary Research》2014,43(1):193-207

The lithostratigraphy of pre‐Late Weichselian sediments and OSL‐dating results from four localities in the Suupohja area of western Finland, adjacent to the centre of the former Scandinavian glaciations, are presented. The studied sections expose glacifluvial, quiet‐water, littoral and aeolian deposits overlain by Middle and/or Late Weichselian tills. Litho‐ and biostratigraphical results together with seven OSL age determinations on buried glacifluvial sediment at Rävåsen (94±15 ka) and on till‐covered littoral and aeolian sediments at Risåsen, Rävåsen, Jätinmäki and Kiviharju (79±10 to 54±8 ka), accompanied by previous datings and interpretations, suggest that the glacifluvial sediments at Risåsen were deposited at the end of the Saalian Stage (MIS 6) and those at Risåsen were deposited possibly in the Early Weichselian Substage (MIS 5d?). Palaeosol horizons and ice‐wedge casts together with the dated littoral and aeolian sediments between the Harrinkangas Formation (Saalian) and the overlying till(s) indicate that western Finland was ice‐free during most of the Weichselian time. Littoral deposits, dated to the Middle Weichselian (MIS 4–3), occur at altitudes of 50–90 m a.s.l., which indicates significant glacio‐isostatic depression. The depression resulted from expansion of the ice sheet in the west of Finland at that time.  相似文献   

Depositional history of peatland pines (Pinus sylvestris L.) in NW Enontekiö, Finnish Lapland: implications for Middle Holocene drought and temperature fluctuations     

Samuli Helama  Hannu Herva  Joonas Uusitalo  Andy Moir  Kari Mielikäinen  Pekka Nöjd  Markku Oinonen  Raimo Sutinen 《Boreas: An International Journal of Quaternary Research》2023,52(3):427-439

High altitude and latitude findings of subfossil peatland pine trees were unearthed from the region of NW Finnish Lapland and dated by ¹⁴C and tree-ring methods. The depositional history of the trees illustrated two distinct peatland pine phases dated to Middle Holocene intervals 4900–4400 and 4100–3400 cal. a BC. It seems evident that both thermal and hydroclimatic fluctuations have played roles of varying importance in the establishment of this pine population and its demise. The presence of these pines, from a site ~60 km north of the coniferous timberline and conditions ~1 °C and 100 degree-days colder than those at the present-day timberline, concurs with previous studies demonstrating the association between the high-latitude summer-temperature cooling and circumpolar timberline retreat since the Middle Holocene due to Milankovitch forcing. On the other hand, the peatland pine recruitment was made possible by drier than present surface conditions during the previously reconstructed Middle Holocene drought anomaly (Hyvärinen-Alhonen event). Our data suggest this event was not continuous but reached its two-phase climax during the peatland pine phases, with an interruption of several centuries with moister surface conditions between 4400 and 4100 cal. a BC. The findings highlight the sensitivity of well-dated peatland tree assemblages in terms of recording past climatic evolution and events and the need for new collections from north and south Fennoscandia and the Baltic region, for more detailed analyses over extended time intervals and regions.  相似文献   

Reflection measurements along the EGT POLAR-profile, northern Baltic Shield     

C-E. Lund  P. Heikkinen 《Geophysical Journal International》1987,89(1):361-364

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Ray asymptotic propagation of the spectra of elastic surface waves in a waveguide with laterally smooth inhomogeneities     

Pekka R. Saastamoinen 《Geophysical Journal International》1984,79(1):269-284

Summary. A technique based on ray asymptotics has been developed to propagate complex spectra of elastic normal mode surface waves in a waveguide with material and geometrical properties varying smoothly in the lateral directions. In the technique, the original problem defined in the unstretched coordinates has been transformed into an eiconal equation as well as into a certain number of transport equations defined in stretched coordinates.
The solution of the eiconal equation is equal to the solution of the eigenproblem of the eiconal operator A₀. Due to the self-adjointness of A₀, in each of the relevant local inner product spaces, LIPS, the solution of the eigenproblem, A₀ψ= v ψ results in the set { v _t} of real local eigenvalues and in the orthonormal system {ψ_t} of local eigenvectors.
As the Hamiltonian function of an initial value problem, each eigenvalues gives birth to a bicharacteristic curve as well as to the related ray. The introduction of the rays induces connections between the vertical cross-sections of the waveguide.
Finally, for each asymptotic order j , the LIPS-valued transport equations are reduced to a set of matricial propagation equations in the local spectral amplitude vectors, LSAVs. Consequently, a knowledge of the initial conditions at a vertical cross-section makes it possible to propagate the LSAVs along the rays of the relevant modes. However, to complete the propagation one needs, in addition to the initial values, information about certain additional quantities, non-diagonal terms of order j , diagonal terms of orders lower than j and the auxiliary boundary terms of orders from 1 to j . The treatment has been completed by the propagation of the modal phases along the relevant rays.  相似文献   

Spatiotemporal characterization of land surface temperature in Mount Kilimanjaro using satellite data     

Eduardo Eiji Maeda  Pekka Hurskainen 《Theoretical and Applied Climatology》2014,118(3):497-509

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