38 KB1866 KB37 KB197320132006Merela, MaksMikac, UrškaOven, PrimožSerša, Igor10 straništevilka:79str. 75-84ISSN:0351-3114COBISSID:1448073URN:URN:NBN:SI:doc-RGMURK77slInštitut za gozdno in lesno gospodarstvoUniverza v Ljubljani, Biotehniška fakulteta, Oddelek za gozdarstvo & Oddelek za lesarstvoZbornik gozdarstva in lesarstvabukevFagus sylvaticaHumiditylesslikanje z magnetno resonancovlažnostUporaba magnetno resonančnega slikanja za raziskave anatomije in vlažnosti lesa|Feasibility of nuclear magnetic resonance (nMR) was tested for research of anatomy and moisture content of wood. A three m high living beech tree (Fagus sylvatica L.) was imaged by magnetic resonance using the 3D spin-echo microscopic imaging technique at isotropic spatial resolution of 100 mm to follow structural changes in the topped branch caused by healing response mechanisms of the tree. Conventional light microscopy was also employed to verify tree structures detected on MR images. Conventional light microscopy revealed anatomical structures and three year age of the tree branch. MR images clearly showed pith, radially oriented xylem rays, early wood vessels with a delineated border between early and late wood, as well as the cambial zone with current xylem and phloem growth increment. We studied water concentration in the branch and the depth of dehydration formed in 22 hours after the mechanical injury. The dehydrated region extended to the mm depth from the wound location. First passive response of the injured branch tissue reflects in the initial decrease of the moisture content that was detected by MR imaging. Finally, we processed 3D MR microscopy data by the ImageJ image processing program to depict the spatial water concentration in the tree branch and to determine tissues with high water contentPreverjena je bila uporaba jedrske magnetne resonance (Nmr) za raziskave anatomije in vlažnosti lesa. Na tri metre visoki živi bukvi (Fagus sylvatica L.) smo uporabili 3d spin-echo mr-mikroskopsko tehniko slikanja s prostorsko resolucijo 100 mm in opazovali strukturo odrezane vejice ter spremljali dinamični odziv drevesa na mehansko poškodbo. Za potrditev struktur, vidnih na slikah, smo uporabili svetlobno mikroskopijo. Svetlobna mikroskopija je razkrila anatomsko zgradbo in triletno starost vejice bukve. Slike so jasno razkrile stržen, radialno orientirane večredne ksilemske trakove, traheje ranega lesa, vključno z mejo med ranim in kasnim lesom, kot tudi kambijevo cono s tekočim ksilemskim in floemskim prirastkom. Preučevali smo koncentracijo vode v vejici in globino dehidracije, ki je nastala v 22-tih urah po poškodbi in je segala v globino približno 5 mm od poškodbe. Hitra izguba vlažnosti odseva začetni pasivni odziv prizadetega tkiva. S pomočjo 3d mikroskopije in računalniškega programa Imagej nam je uspelo izdelati prostorski model vode v lesu, ki prikazuje tkiva v vejici z značilno višjo vlažnostjoTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Biotehniška fakulteta