Search

Acetone extracts of sapwood and reaction zone of spruce roots attacked by Fomes annosus, collected in February, June and October, were separated into resinous and phenolic fractions. The fractions were further separated by column, thin layer and gas liquid chromatography, followed by biological tests, using Fomes annosus and other rot fungi. The reaction zone contained quantitatively less light petroleum soluble compounds than the sapwood but more acids. The phenolic content was about ten times higher in the reaction zone than in the sapwood. Nine lignans and one simple phenol (4-methylcatechol) were identified and quantitatively estimated in the reaction zone. The resinous fraction of the extract from the reaction zone as well as some of the lignans and 4-methylcatechol inhibited fungal growth, in some cases followed by detoxification and continued growth. The predominant lignan, hydroxymatairesinol, had no effect on Fomes annosus or five other wood degrading fungi. About 15 unidentified phenols were observed, some of them probably of importance as inhibitors, either alone or in combination with other phenols.

In the spring of 1977, scattered trees in young plantations of Norway spruce showed discoloration and loss of 1976 needles on twigs just below the apex. The main roots of damaged trees were smaller than those of healthy trees, and the extension roots lacked short roots and mycorrhizae. The transpiration rate of the current shoots of damaged trees was also higher. The damage was assumed to be the result of drought during the two previous years; the trees were thought to differ genetically in their ability to withstand water stress.

Cambial electrical resistance (CER) of Norway spruce (Picea abies Karst.) was measured in relation to wood temperature. The linear function obtained was used to correct CER values from field experiments to a standard temperature. A fairly good correlation was obtained between the growth rate and CER of both dominant and suppressed trees. The average value of CER in a sample of spruce trees was relatively low in summer, increased by 100% in the autumn and started decreasing again the following March. Drought stress in a field experiment resulted in a significant increase in CER, which was inversely correlated with bark moisture. A review of the literature concerning the use of CER is presented, and the relevance of estimating CER is discussed, particularly regarding stress and diseases.

Doping is not only a medical-legal issue. The increase in doping results from increasing international competition, the market economy and the increasing national significance of sport. The ethical problems of the researchers are pointed out. The gradually stricter measures taken by the Swedish Sport Federation against doping are described. The debate on doping in the daily papers after the Olympic Games in Los Angeles in 1984 was characterized by moral indignation and an increasingly cynical attitude to top sport. These reactions are interpreted in the light of an historical analysis of the development of sport and its ideological manifestation in Swedish society.

A comparison was made of the fungistatic effects of the root microflora of grey alder and Norway spruce with Fomes annosus as test fungus. The significantly higher frequency of actinomycetes in the alder rhizosphere probably constituted the main difference in this respect. The importance of fungi seemed to be about equal in the rhizosphere of the two tree species. Methods for studies of antagonism are tested and discussed.

Fractions of acetone extracts from heartwood, sapwood and wood from the reaction zone in roots of Norway spruce, attacked by Fomes annosus, were tested concerning their effect on the activity of cellulase, polygalacturonase, aryl-β-glucosidase and laccase, obtained from culture filtrates of the same fungus. A specific inhibition of polygalacturonase was recorded with the resinous fractions. The hydrolysing enzymes were more inhibited by the lignans of the reaction zone in the presence of fungal laccase than in the absence of laccase. The pH dependence of the inhibiting effect of phenols varied among the enzymes. The four enzymes were inhibited by partly different lignan fractions, and synergistic effects between minor compounds were indicated. The phenolic fractions inhibited weakly the biosynthesis of the enzymes. It was obvious that results from enzyme inhibition studies in vitro do not reflect the complicated mutual interrelationships between production and activity of the extracellular fungal enzymes and the chemical constituents of the host in vivo.

About 70 strains of white and brown rot fungi were cultivated on media, containing filter paper cellulose as the main carbon source. The cellulolytic activity of the culture filtrates was measured after different periods of growth by means of the turbidimetric method. The results obtained indicate a difference between the two types of wood decay fungi as to the capacity of attacking the cellulose used in the medium and in the cellulase test. No significant C1activity was found in any of the brown rot cultures whereas all white rot fungi tested exerted a measurable activity on the test substrate. The effect of various carbohydrates and some proteins as inducers of cellulase activity was studied. Especially cellobiose and lactose were active on white rot fungi in this respect, particularly in the presence of yeast extract. Also some brown rot fungi exerted C1-activity after incubation on glucose or cellobiose.

Lifetime is a critical parameter in ubiquitous, battery-operated sensors for machine-to-machine (M2M) communication systems, an emerging part of the future Internet of Things. In this paper, the performance of radio frequency (RF) to DC energy converters using transparent and flexible rectennas based on graphene in an ambient RF energy-harvesting scenario is evaluated. Full-wave electromagnetic (EM) simulations of a dipole antenna assuming the reported state-of-the-art sheet resistance for few-layer, transparent graphene yields an estimated ohmic efficiency of 5%. In the power budget calculation, the low efficiency of transparent graphene antennas is an issue because of the relatively low amount of available ambient RF energy in the frequency bands of interest, which together sets an upper limit on the harvested energy available for the RF-powered device. Using a commercial diode rectifier and an off-the-shelf wireless system for sensor communication, the graphene-based solution provides only a limited battery lifetime extension. However, for ultra-low-power technologies currently at the research stage, more advantageous ambient energy levels, or other use cases with infrequent data transmission, graphene-based solutions may be more feasible.

In this paper the scattering properties of an infinite grid of conducting strips in a multilayer structure is studied by a spectral domain technique. To calculate the scattered field we Fourier expand the induced currents on the strips and use the numerical algorithm GIDMULT to evaluate the spectral domain Green's functions. The results are compared with data obtained using the asymptotic strip boundary condition (ASBC). We have shown that the exact numerical results approach the ASBC results when the strip period decreases for all relative strip widths. This paper is done while Zvonimir Sipus was a Ph.D. Student at Chalmers University of Technology, Gothenburg, Sweden.

Strains of Heterobasidion annosum belonging to the S and P intersterility groups (IGs) were compared in respect of laccase activity on various substrates. Biomass production was significantly lower in P cultures than in S cultures. By contrast, laccase activity, measured in relation to growth rate, was significantly higher for the P strains tested, compared with a similar number of S strains, particularly in substrates, rich in carbohydrates as well as in inorganic and organic nitrogen. Using the Bradford assay method, P cultures were shown to contain significantly higher amounts of protein than S. The pH optimum of laccase for both IGs was 4.5 with guaiacol as substrate and 5.3 with syringaldazine. Isozyme patterns varied greatly, depending on strain, substrate and incubation time. In P cultures 4–5 bands were obtained, whereas S strain laccase was mostly separated into 2–3 isozyme bands. Only one was significantly different in position between the IGs. The results may help to explain why P strains are more aggressive than S strains as pathogens and wood decayers.

A number of aromatic compounds, related to conifer wood and bark, were compared in terms of their effects on the laccase activity of strains of the S and P intersterility groups (IGs) of Heterobasidion annosum .Under most conditions — in both liquid and solid media — the laccase activity of P strains, measured in relation to biomass production, was significantly higher compared with that of S strains.P strains released mostly significantly higher amounts of proteins in an early growth phase, which somewhat reduced the difference in laccase activity between the IGs, in terms of specific activity.Laccase activity in both IGs was stimulated by a pine bark extract and phenolic acids - stilbenes as well as flavanoids and proanthocyanidines — and some other low-molecular weight phenolic compounds.However, only nonpolar compounds were active.The degree of stimulation of specific laccase activity by phenolics was generally higher in P strains: significant with pinosylvin, piceid, taxifolin, catechin, ferulic acid and cinnamic aldehyde.The oxidative capacity of culture filtrates of P strains, as determined with an oxygen electrode, was significantly higher than that of S strains with astringin, isorhapontin, taxifolin, catechin and proanthocyanidines, and with water-soluble extractives of Scots pine wood and bark.The pathological significance of these results in relation to the host preferences and the differential aggressiveness of S and P types is discussed.

Particle number size distributions at various field sites are used to identify atmospheric new-particle formation (NPF) event days. However, the spatial distribution of regionally extensive events is unknown. To remedy this situation, the NanoMap method has been developed to enable the estimation of where NPF occurs within 500 km from any field station using as input size distribution and meteorological trajectories only. Also, the horizontal extension of NPF can be determined. An open-source program to run NanoMap is available on the internet. NanoMap has been developed using as an example the Finnish field site at Hyytiala. It shows that there are frequent NPF events over the Baltic Sea, but not as frequent as over Finland for certain wind directions; hence NanoMap is able to pinpoint areas with a low or high occurrence of NPF events. The method should be applicable to almost any field site.

In this paper, we investigate how directional and highly-directional antenna systems using fixed beams can be beneficial in terms of aggregated channel and antenna gains, channel correlation and the massive multiple-input multiple-output (MIMO) capacity in both line-of-sight (LOS) and non-LOS (NLOS) scenarios for single user MIMO (SU-MIMO). It is shown that narrower beams have stronger aggregated channel and antenna gain. However, narrow beamwidth triggers a higher channel correlation as fewer scatterers are seen. A possible solution to reduce the correlation among the beams is to properly decorrelate the beams in advance. To this end, we partition the area of interest and devote one specific partition to each beam to minimize the possible overlaps among the beams. Simulation results show that fixed beam SU-MIMO systems using such highly-directional beams can provide higher MIMO capacity in comparison to isotropic and directional antenna systems.

The importance of root and spore surface molecules in the interactions of Fusarium spp. with conifer roots, and cellular localization of proteins presumed to be involved in host defence, were investigated. For adhesion studies, using a combination of fluorescein isothiocyanate (FITC) labelled lectins and high perfomance liquid chromatography (HPLC), several sugars (pinitol, xylitol, galactose, mannose, and glucose) were detected in root surface mucilage. Both artificial substrata and detached living roots were used to evaluate the significance of selective removal of root or spore surface components on the adhesion process. The spores or roots were pretreated with either periodic acid, pronase E, potassium hydroxide or diethyl ether. Pretreatment of the spores with diethyl ether reduced significantly the level of spore adhesion, which suggests that the adhesive component is either a lipid, or is bound to lipid. Since oxidation of carbohydrate reactive sites with periodic acid on the root surface almost completely abolished the development of germ tubes by adherent spores, it was presumed that some of these periodate-sensitive substances serve as a nutrient source for the fungus. On inoculated roots, F. avenaceum and F. culmorum were significantly pathogenic to both Norway spruce and Scots pine seedlings. Cytochemical labelling of sites of accumulation of host defence molecules within infected root tissues using anti-peroxidase demonstrated increased peroxidase activity in host cell walls. With anti-chitinase and anti-glucanase, gold labelling was found mainly on pathogen hyphal walls.Key words: conifer seedlings, adhesion, Fusarium spp., PR proteins, immunolocalization, lectins.

Due to demands from industry on improved efficiency, reduced CO2 and NOx and decreased noise levels, the trend of future aero engines show that turbofan engines are designed with higher by-pass ratio. Two-spool and three-spool turbofan engines are designed with an intermediate turbine duct that connects the high-pressure turbine to the low-pressure turbine in the two-spool engine and two intermediate turbine ducts from HPT to intermediate pressure turbine (IPT) and IPT to LPT in the three-spool engines. The design of agressive intermediate turbine ducts (high radial offset for a short axial length) for these engines enables the possibility to increase the energy efficiency of the aero engine. The flow and heat transfer in a turbine duct is very complex. The flow has large secondary structures and is sensitive to flow separation, which is difficult to predict with numerical methods. Limited information is available in open literature that can be used for validation of numerical methods. This paper presents an experimental study of the heat transfer in an aggressive intermediate turbine duct. The aim of this study is to measure the of a surface temperature distribution and convection heat transfer coefficient with very high resolution and precision on a loaded guide vane which is located inside the intermediate turbine duct. Furthermore, the experimental results are compared to CFD carried out with ANSYS CFX. This experiment was carried out in a state-of-the-art large-scale low-speed turbine facility at Chalmers University of Technology. The duct configuration investigated represents a modern counter rotating turbine design, with a flow turning structural vane. The facility includes a turbine stage which provides realistic inlet conditions into the duct and operates at realistic flow Reynolds number based on the ITD vane chord length. The measurements were performed by using an infrared camera. The results shows that the heat transfer coefficient predicted in the computations close to the shroud is not well predicted. There can also be seen areas where there is flow transition and boundary layer transition.

The interaction between the root rot fungus (Heterobasidion annosum) and seedling roots of Norway spruce was studied using scanning and transmission electron microscopy, light microscopy, and immunohistochemistry. Results showed that attachment to root surface and penetration of root epidermal walls were facilitated using pregerminated conidiospores as inocula. High inoculum concentrations (107 spores/mL) were also required for rapid colonization and establishment of the pathogen in the cortex. At lower spore concentrations, fewer hyphae were detected within the cortical region. The induction of hypersensitive response was a function of both time and spore concentration. Formation of infective structures on the root surface was evident 24 h after inoculation. Internal colonization of cortical tissues started 24–48 h postinoculation and reached the endodermis within 72 h. Severe destruction of stelar cells was observed 12 – 15 d postinfection. Cell invasion by the pathogen was correlated with formation of papillae and lignification in cortical cells. Increases in the enzymatic activity of defence-related proteins (chitinase and peroxidase) of infected roots were also evident. When vascular tissues were severely damaged disruption of endodermal cells was also recorded using light microscopy. The presence of H. annosum antigenic materials within cell wall boundaries suggests intercellular penetration by the pathogen. Key words: Norway spruce, Heterobasidion annosum, histochemistry, immunofluorescence, chitinase, peroxidase.

Background The kidneys are regarded as one of the main dose-limiting organs in the treatment of neuroendocrine tumours with 177Lu-[DOTA0, Tyr3]-octreotate (177Lu-octreotate), despite the successful use of kidney uptake blocking agents such as lysine and arginine. To avoid renal toxicity but still give each patient as high amount of 177Lu-octreotate as possible, there is a need for methods/biomarkers that indicate renal injury in an early stage of the treatment. The aim of this study was to investigate the potential of using urinary retinol binding protein 4 (RBP4) and carbamoylated haemoglobin (Hb) in blood as biomarkers of nephrotoxic effects on adult mice after 177Lu-octreotate treatment. Methods Adult BALB/c nude mice were injected with 60 MBq or 120 MBq of 177Lu-octreotate or with saline (control). Urine was collected before injection and concentrations of urinary RBP4 and creatinine were determined 14 to 90 days after injection Blood samples were collected after 90 days, and carbamoylated N-terminal valine in Hb, formed from urea, was measured as valine hydantoin (VH) after detachment from Hb. Results The RBP4 values increased with administered activity and time. For the 60 and 120 MBq groups, statistically significantly higher RBP4 levels (p 0.05). No morphological changes in the kidney tissue were found. Conclusions Urinary RBP4 is a promising new biomarker for radiation-induced renal toxicity. For the conditions used in this experiment, carbamoylated Hb (from urea) measured as VH may not be a sufficiently sensitive biomarker to be used for renal toxicity. Trial registration ID 326-2008

Background B-cell leukemia 3 (Bcl-3) is a member of the inhibitor of κB family, which regulates a wide range of biological processes by functioning as a transcriptional activator or as a repressor of target genes. Elevated expression, sustained nuclear accumulation, and uncontrolled activation of Bcl-3 causes increased cellular proliferation or survival, dependent on the tissue and type of stimuli. Methods We retrospectively reviewed patients who were diagnosed with colorectal cancer at Skåne University Hospital in Malmö between 1st of January 1990 and 31st of December 1991. Bcl-3 localization in colorectal cancer was assessed by immunohistochemistry on tissue microarray and freshly isolated colon from patients. Correlation between Bcl-3 localization and clinicopathological parameters of the cohort were evaluated using the Spearman rank-order correlation coefficient. In addition, Bcl-3 expression and localization in colon adenocarcinoma cells were analysed by western blot, immunohistochemistry and subcellular fractionation separately. Results We found that Bcl-3 was mainly localized in the cytoplasm in the tumour tissue isolated from colon cancer patients. Normal colon samples from the same patients showed Bcl-3 localization in the nucleus. In three out of six colon cancer cell lines, we detected elevated levels of Bcl-3. In these cell lines Bcl-3 was accumulated in the cytosol. We confirmed these findings by analysing Bcl-3 localization in a colon tissue micro array consisting of 270 cases. In these samples Bcl-3 localization correlated with the proliferation marker Ki-67, but not with the apoptotic marker Caspase 3. Conclusion These findings indicate that analysis of the subcellular localization of Bcl-3 could be a potential-early diagnostic marker in colon cancer.

Introduction Toll-like receptors (TLRs) are a family of pattern recognition receptors that are expressed on cells of the innate immune system. The ligands can be pathogen derived (pathogen associated molecular patterns; PAMPs) or endogenous (damage associated molecular patters; DAMPs) that when bound induces activation of nuclear factor kappa B (NF-κB) and transcription of pro-inflammatory genes. TLRs have also been discovered in various malignant cell types, but with unknown function. Methods In this study we performed a detailed analysis of TLR and co-receptor expression pattern and function in breast cancer. Expression patterns were examined using real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC) on three estrogen receptor-positive (ER+) and four estrogen receptor/progesterone receptor-negative (ER−/PR−; ER/PR-negative) breast cancer cell lines, and a breast cancer cohort consisting of 144 primary breast cancer samples. The function was investigated using in vitro assays comprising PAMP/DAMP-stimulation, downstream signaling and TLR-silencing experiments. Results We found that TLR4 was expressed in a biologically active form and responded to both PAMPs and DAMPs primarily in ER/PR-negative breast cancers. Stimulation of TLR2/4 in vitro induced expression of pro-inflammatory genes and a gene expression analysis of primary breast cancers showed a strong correlation between TLR4 expression and expression of pro-inflammatory mediators. In line with this, TLR4 protein expression correlated with a decreased survival. Conclusions These findings suggest that TLR4 is expressed in a functional form in ER/PR-negative breast cancers. Studies regarding TLR4-antagonist therapies should be focusing on ER/PR-negative breast cancer particularly. Electronic supplementary material The online version of this article (doi:10.1186/s13058-015-0640-x) contains supplementary material, which is available to authorized users.

Geometry-based stochastic channel models (GSCMs) are suitable models at millimeter-wave (mm-wave) frequencies. Proper forward-scattering and back-scattering modeling is needed in order to realize realistic channel assessments. In this paper, a recently-proposed back-scattering model, 3D Fresnel, goes through further investigations: first, we investigate the impact of frequency in the results of a single scenario and, second, we study the effect of multiple surfaces. In both cases, the model shows good agreement with respect to the Physical Optics (PO) reference model.

Summary With aid of fluorescein isothiocyanate (FITC) and gold-labelled lectins, together with antibodies against chitinase and β-1,3-glucanases, the spatial distribution of chitin and glucans in hyphal walls of Pythium dimorphum, a causative agent of root die-back disease of conifer seedlings was studied. Contrary to previous reports, this study revealed that chitin, a polymer of N-acetyl-d-glucosamine, is a component of the cell wall of this oomycetous fungus. However, compared with the other amino sugar, N-acetyl-galactosamine, it is not present in significant amounts. Ultrastructural and labelling studies demonstrated that the chitin region is embedded in or masked by glucan residues.

Non-suberized seedling roots of Norway spruce (Picea abies) were challenged in vitro under sterile conditions with oidiospores from the saprotrophic basidiomycete Phlebiopsis gigantea. The root surface supported spore germination and mycelial growth. Samples were taken at defined time intervals for histochemical, SEM and TEM observations. Infective structures developed 24–48 h post inoculation (p.i). Appressoria appeared to be induced by ridges or groove-like structures on the root surface and by similar structures created by mycelial mats. Penetration into epidermal cells occurred 3 d p.i. with cortical and meristematic colonization observed 4–5 d p.i. Browning reactions of the root surface occurred within 5 d p.i. at high spore concentrations but were delayed at lower inoculum concentrations. The inoculum threshold for penetration of epidermal cells and colonization within 5 d p.i. was 104 spores ml−1. Invasion and disruption of root vascular regions were not observed with any inoculum. At the TEM level, tissue colonization was primarily intercellular by cell to cell hyphal development within middle lamellae. The presence of a translucent layer ahead of fungal hyphae during cell wall penetration was probably caused by the action of hydrolytic enzymes secreted by the invading fungi. Host responses were mostly marked by encasing of hyphae within an electron dense layer, formation of reaction zones and retraction of the plasmalemma of cortical cells. However, the majority of inoculated seedling roots examined were not rotted in contrast to spruce roots inoculated with a common pathogenic basidiomycete (Heterobasidion annosum).