Xylogenesis dynamics in sessile oak during 2007

S svetlobnim mikroskopom smo raziskali sezonsko dinamiko nastanka lesa pri gradnu (Quercus sessiliflora Salisb.) v rastni sezoni 2007. Konec marca so se delitve v kambiju že začele in število celic je naraslo na 10-11 slojev. Maksimalno celično produkcijo smo na ksilemski strani zabeležili v drugi polovici maja, ko smo ugotovili prek 100 ?m prirastka na teden. Kambijeva aktivnost se je zaključila do sredine avgusta in število celic je upadlo na 5-7 slojev. Oblikovanje sekundarne stene in lignifikacija v terminalnih celicah kasnega lesa pa sta potekala še nadaljnjih 4-5 tednov. Dinamika nastanka lesa pri gradnu se razlikuje od debelinske rasti iglavcev.We investigated seasonal dynamics of wood formation in sessile oak (Quercus sessiliflora Salisb.) during the vegetation period of 2007, using light microscope. Divisions in the cambium already started at the end of March when the number of cells increased up to 10-11 layers. Maximal cell production was recorded in the second half of May when more than 100 ?m of the increment was formed per week. Cambial activity ceased by mid-August and the number of cambial cells diminished to 5-7 layers. However, secondary cell wall formation and lignification of terminal late wood cells took place for additional 4-5 weeks. The dynamics of wood formation in sessile oak differs from radial growth patterns of conifers

Application of controlled experiments for studies of radial tree growth

V članku je predstavljen pregled objav o nadzorovanih poskusih ogrevanja in hlajenja dreves ter njihov pomen za raziskave debelinske rasti dreves. Poskusi, ki so jih opravili različni raziskovalci na številnih vrstah, so pokazali, da je mogoče vplivati na delovanje kambija in procese nastanka lesa in floema ter s tem na njuno anatomsko zgradbo, vendar pa se je kambij pri različnih vednozelenih in listopadnih drevesnih vrstah različno odzival na lokalno povišane oz. znižane temperature. Naši najnovejši rezultati pa kažejo, da utegne tudi starost dreves oziroma debelina skorje (lubja) vplivati na učinek tovrstnih eksperimentov na kambijevo delovanje in razvoj celic.In the paper, a review of publications on controlled experiments of heating and cooling of trees and their significance for the studies of radial tree growth is presented. The experiments carried out by different researchers in anumber of tree species have demonstrated that it is possible to affect cambial activity and processes of wood and phloem formation and by that their anatomical structurehowever, the response of cambium to locally elevated or decreased temperatures differed in various evergreen and deciduous tree species. Our most recent findings indicate that tree age and thickness off bark (i.e. outer dead bark) appear to influence the extent of such experimentson cambial activity and cell development

Inovativni razvoj e-regije, ki sega prek državnih meja: možne usmeritve in učinki

Regional development policy has to respond to the challenges of a global, informational and networked economy. In order to achieve a regional-innovation-focused competitive advantage it is important for the region to have the ability both to access and generate knowledge, and to access to knowledge networks faster than its competitive regions. In this paper, challenges in the area of eRegion development are discussed and some eRegion development initiatives are presented. Some activities from the period 2000-2006 are elaborated on, as are current initiatives in the Central Europe eRegion. Possible suggestions and some questions are concerning about a growing need in the eRegion for innovative ways of business, government and academic collaboration as part of a continuous process.Regionalna razvojna politika mora najti odgovor na izzive globalnega, informacijskega in mrežnega gospodarstva. Da bi dosegli regionalno inovacijsko usmerjeno konkurenčno prednost, je pomembno, da ima regija možnost tako dostopa do znanja kot tudi njegovega ustvarjanja, in sicer da lahko dostopa do mrež znanja hitreje kot njej konkurenčne regije. V tem prispevku so obravnavani izzivi na področju razvoja e-regij ter predstavljene nekatere razvojne pobude povezane z e-regijami. Obdelane so nekatere aktivnosti iz obdobja 2000-2006 kot tudi zdajšnje pobude v srednjeevropski e-regiji. Možne sugestije in nekatera vprašanja se nanašajo na rastočo potrebo v e-regijah po inovativnih načinih poslovanja, upravljanja in akademskega sodelovanja kot dela nepretrganega procesa

The impact of determinants of supply and demand on prices in the catering industry

Z metodo glavnih komponent smo ugotovili dve skupni komponenti, s katerima je mogoče pojasniti skupne dejavnike analiziranih spremenljivk, in sicer splošna raven cen in plače v gostinstvu ter uvedba evra, stabilnost cen v evrih in povpraševanje po gostinskih storitvah. z multiplo regresijsko analizo je bilo ugotovljeno, da so cene gostinskih storitev kratkoročno pozitivno in statistično značilno povezane z uvedbo evra, povpraševanjem po gostinskih storitvah in rastjo cen hrane in brezalkoholnih pijač kot vmesnimi stroški vlokov (inputov). Uporabljeni so mesečni podatki Statističnega urada Republike Slovenije od leta 2000 do leta 2007.The principal component analysis confirms two common components, identified as the general level of prices and wages in the catering industry and the adoption of the Euro, Euro price stabilisation, and demands for catering industry service. The multiple regression analysis confirms a positive and statistically significant association of the catering industry prices with adoption of the Euro, tourists\u27 demand, and the rise of prices of food and non-alcoholic beverages as intermediate input costs that are found to be significant drivers for the increases of the catering industry prices. The empirical analysis on the factors of inflation in the catering industry is based on the monthly statistical data from 2000 to 2007

Application of transmission electron microscopy and UV-microspectrophotometry for detection of lignin in cell wall of conifers

Kalijev permanganat je kot reagent v transmisijski elektronski mikroskopiji (TEM) zelo uporaben za ugotavljanje prisotnosti lignina v različnih morfoloških področjih lesa. Ker je metoda le kvalitativna, je priporočljivo rezultate, ugotovljene s TEM, potrditi še s kakšno drugo kvantitativno metodo,kot je npr. UV-mikrospektrofotometrija (UMSP). Metoda UMSP je zelo primerna za določanje vsebnosti lignina in njegove porazdelitve v lesnem tkivu. V članku je predstavljena metodologija in uporabnost TEM ter UMSP pri proučevanju porazdelitve lignina v celični steni.Potassium permanganate represents a useful tool in transmission electron microscopy (TEM) for the localization of lignin in various morphological regions of wood. Since this method only provides qualitative estimation, another quantitative method is recommended to verify the results obtained by TEM, such as UV-microspectrophotometry (UMSP). The UMSP method was found to besuited for the determination of lignin content and its distribution in woodytissue. The present paper provides a methodical description and presents the applicability of TEM and UMSP for studies in the topochemistry of lignin distribution within cell walls

Secondary Cell Wall Formation and Lignification of Latewood Tracheids near Cambium in Silver Fir (Abies alba) during Dormant Period

The aim of this study was to investigate the process of differentiation of terminal latewood tracheids near the cambium in silver firs (Abies alba) during dormant period. Samples of wood and cambium were taken from 10 apparently healthy mature trees in the middle of October, November and March. According to light microscopy, transmission electron microscopy and UV–microspectrophotometry, cambial cell-divisional activity was completed in all investigated trees in October, whereas process of differentiation was still ongoing in the youngest tracheids close to the cambium in trees with broader annual xylem growth rings. Layer S3 of the secondary cell wall and warty layer were not formed and inner parts of S2 layer of secondary cell wall were not yet lignified. Only four weeks later, in November, the cell wall formation and the lignification of terminal latewood tracheids close to the cambium were completed in all trees. No alterations were observed at the ultrastructural level between November and March samples. The cambial cell-divisional activity and also differentiation ended later in trees with broader annual xylem growth rings. However, differentiation of terminal latewood tracheids in all investigated trees was completed before winter