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21.
Gerald Dirnberger Hubert Sterba Sonia Condés Christian Ammer Peter Annighöfer Admir Avdagić Kamil Bielak Gediminas Brazaitis Lluís Coll Michael Heym Václav Hurt Viktor Kurylyak Renzo Motta Maciej Pach Quentin Ponette Ricardo Ruiz-Peinado Jerzy Skrzyszewski Vít Šrámek Géraud de Streel Miroslav Svoboda Tzvetan Zlatanov Hans Pretzsch 《European Journal of Forest Research》2017,136(1):171-183
Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) dominate many of the European forest stands. Also, mixtures of European beech and Scots pine more or less occur over all European countries, but have been scarcely investigated. The area occupied by each species is of high relevance, especially for growth evaluation and comparison of different species in mixed and monospecific stands. Thus, we studied different methods to describe species proportions and their definition as proportion by area. 25 triplets consisting of mixed and monospecific stands were established across Europe ranging from Lithuania to Spain in northern to southern direction and from Bulgaria to Belgium in eastern to western direction. On stand level, the conclusive method for estimating the species proportion as a fraction of the stand area relates the observed density (tree number or basal area) to its potential. This stand-level estimation makes use of the potential from comparable neighboring monospecific stands or from maximum density lines derived from other data, e.g. forest inventories or permanent observations plots. At tree level, the fraction of the stand area occupied by a species can be derived from the proportions of their crown projection area or of their leaf area. The estimates of the potentials obtained from neighboring monospecific stands, especially in older stands, were poorer than those from the maximum density line depending on the Martonne aridity index. Therefore, the stand-level method in combination with the Martonne aridity index for potential densities can be highly recommended. The species’ proportions estimated with this method are best approximated by the proportions of the species’ leaf areas. In forest practice, the most commonly applied method is an ocular estimation of the proportions by crown projection area. Even though the proportions of pine were calculated here by measuring crown projection areas in the field, we found this method to underestimate the proportion by 25% compared to the stand-level approach. 相似文献
22.
23.
Viktor Szatmári 《Veterinary radiology & ultrasound》2003,44(4):486-7; author reply 487
24.
The aim of this study was to investigate the effect of prehandling stress on the flesh quality of Atlantic cod (Gadus morhua). In order to stress the animal, water was reduced in the tank before a total of 30 fish were caught five at a time using a dipnet and held for 3 min, causing stress by hypoxia. This fish was compared with a control group (n=30) of fish exposed to anaesthetics directly in the tank. All fish were killed by a percussive blow to the head and exsanguinated and stored on ice before flesh quality was measured. Immediately after death and after ice storage for 3 and 8 days, 10 fish per group were measured for muscle pH, texture, fillet gaping, colour, drip loss and cathepsin D. Handling stress resulted in an initial increased fillet lightness, drip loss and decreased fillet shear force, although these differences did level off during ice storage. Stress caused by handling resulted in earlier onset of rigour mortis as compared with the control group, which reached maximum rigour tensions within 26 and 36 h postmortem respectively. We conclude that handling before harvest results in reduced time before entering rigour. After 8 days of ice storage, no effect of handling stress was seen on the muscle pH, flesh colour, fillet shear force, gaping score, drip loss or cathepsin D activity. 相似文献
25.
Ferenc Jordán Tibor Magura Béla Tóthmérész Vera Vasas Viktor Ködöböcz 《Landscape Ecology》2007,22(10):1527-1539
For many species, one important key to persistence is maintaining connectivity among local populations that allow for dispersal
and gene flow. This is probably true for carabid species (Coleoptera:Carabidae) living in the fragmented forests of the Bereg
Plain (NE Hungary and W Ukraine). Based on field data, we have drafted a landscape graph of the area representing the habitat
network of these species. Graph nodes and links represented two kinds of landscape elements: habitat (forest) patches and
corridors, respectively. The quality of habitat patches and corridors were ranked (from low (1) to high (4)), reflecting local
population sizes in the case of patches and estimated permeability in the case of corridors. We analysed (1) the positional
importance of landscape elements in maintaining the connectivity of the intact network, (2) the effect of inserting hypothetical
corridors into the network, (3) the effects of improving the quality of the existing corridors, and (4) how to connect every
patch in a cost-effective way. Our results set quantitative priorities for conservation practice by identifying important
corridors: what to protect, what to build and what to improve. Several network analytical techniques were used to account
for the directed (source-sink) and highly fragmented nature of the landscape graph. We provide conservation priority ranks
for the landscape elements and discuss the conditions for the use of particular network indices. Our study could be of extreme
relevance, since a new highway is being planned through the area. 相似文献
26.
Superconductivity in compressed lithium is observed by magnetic susceptibility and electrical resistivity measurements. A superconducting critical temperature (Tc) is found ranging from 9 to 16 kelvin at 23 to 80 gigapascals. The pressure dependence of Tc suggests multiple phase transitions, consistent with theoretical predictions and reported x-ray diffraction results. The observed values for Tc are much lower than those theoretically predicted, indicating that more sophisticated theoretical treatments similar to those proposed for metallic hydrogen may be required to understand superconductivity in dense phases of lithium. 相似文献
27.
Yulia A. Logashina Yulia A. Palikova Viktor A. Palikov Vitaly A. Kazakov Sviatlana V. Smolskaya Igor A. Dyachenko Nadezhda V. Tarasova Yaroslav A. Andreev 《Marine drugs》2021,19(1)
Arthritis is a widespread inflammatory disease associated with progressive articular surface degradation, ongoing pain, and hyperalgesia causing the development of functional limitations and disability. TRPV1 channel is one of the high-potential targets for the treatment of inflammatory diseases. Polypeptide APHC3 from sea anemone Heteractis crispa is a mode-selective TRPV1 antagonist that causes mild hypothermia and shows significant anti-inflammatory and analgesic activity in different models of pain. We evaluated the anti-inflammatory properties of APHC3 in models of monosodium iodoacetate (MIA)-induced osteoarthritis and complete Freund’s adjuvant (CFA)-induced rheumatoid monoarthritis in comparison with commonly used non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac, ibuprofen, and meloxicam. Subcutaneous administration of APHC3 (0.1 mg/kg) significantly reversed joint swelling, disability, grip strength impairment, and thermal and mechanical hypersensitivity. The effect of APHC3 was equal to or better than that of reference NSAIDs. Protracted treatment with APHC3 decreased IL-1b concentration in synovial fluid, reduced inflammatory changes in joints, and prevented the progression of cartilage degradation. Therefore, polypeptide APHC3 has the potential to be an analgesic and anti-inflammatory substance for the alleviation of arthritis symptoms. 相似文献
28.
Szatmári V van Sluijs FJ Rothuizen J Voorhout G 《Journal of the American Veterinary Medical Association》2003,222(8):1086-92, 1077
A method for intraoperative measurement of portal blood flow velocity with duplex Doppler ultrasonography in 7 dogs with congenital intrahepatic portosystemic shunts is described. The aims of the study were to determine whether intraoperative ultrasonography was an acceptable alternative to mesenteric portography in such dogs and to identify quantitative portal hemodynamic variables that might correlate with clinical outcome better than portal pressure does. Ultrasonographic measurements did not influence decision-making by the surgeon, who attenuated the shunt on the basis of appearance of the viscera and change in mean systemic arterial blood pressure. All dogs recovered without complications, and surgery was considered to be successful in all 7. Intraoperative B-mode ultrasonography provided real-time information about the anatomy of the shunt and the portal branches, suggesting that it may be a useful alternative to mesenteric portography. The time-averaged mean portal blood velocity ranged from 6.5 to 33.7 cm/s before shunt attenuation and from 5.0 to 9.5 cm/s after shunt attenuation. This narrow range of postligation velocities suggested that intraoperative ultrasonography might be an alternative to intraoperative portal pressure measurement. 相似文献
29.
Tomas Policar Vlastimil Stejskal Jiri Kristan Peter Podhorec Viktor Svinger Martin Blaha 《Aquaculture International》2013,21(4):869-882
The effect of initial fish size (small with TL = 40.3 ± 2.3 mm and W = 0.42 ± 0.15 g, medium with TL = 56.2 ± 2.7 mm and W = 1.66 ± 0.4 g, and big with TL = 71.0 ± 3.2 mm and W = 2.95 ± 0.65 g) and stocking density of identical fish with TL = 40.3 ± 2.3 mm and W = 0.42 ± 0.15 g (1; 2; 4; 8 fish l?1) on weaning success was evaluated in pond-cultured pikeperch. The trial was divided into weaning (12 days) and post-weaning (16 days) periods. Small juveniles reached significantly higher specific growth rate (SGR = 1.6 ± 0.2 % day?1) and survival rate (S = 81.7 ± 2.7 %) and lower cannibalism (C = 3.0 ± 0.75 %) compared to medium and large juveniles (SGR = 0.3–0.5 % day?1, S = 65.3–76.5 %, C = 6.5–7.5 %) during the weaning period. The higher survival rate was found at the two higher densities (S = 72.0–79.1 %) during the weaning period. The lowest survival rate (S = 38.9 ± 2.7) was observed at the lowest fish density. Fish stocking density did not affect growth, condition, or cannibalism rate during the weaning period. Similar trends of growth, survival, and cannibalism of weaned juveniles were observed during the post-weaning period. A mass weaning trial verified experimental results showing small pikeperch juveniles to reach satisfactory growth rate (SGR = 1.4 ± 0.1 and 7.2 ± 0.2 % day?1), survival (S = 78.7 ± 3.0 % and 97.6 ± 1.0 %), and cannibalism (C = 4.0 ± 1.5 % and 2.5 ± 1.0 %) rates during the weaning and post-weaning periods. No body or fin deformities of weaned juveniles were observed. 相似文献
30.
IMAGING DIAGNOSIS — MAGNETIC RESONANCE IMAGING OF INTRACRANIAL INFLAMMATORY FIBROSARCOMA IN A MIXED BREED DOG 下载免费PDF全文
Elena Scarpante Viktor Palus Brian Alan Summers Abby Caine Giunio Bruto Cherubini 《Veterinary radiology & ultrasound》2016,57(1):E5-E9
An 8‐year‐old mixed‐breed dog presented with progressive behavioral changes and altered mentation. Magnetic resonance imaging (MRI) of the brain revealed an olfactory and frontal lobe extra‐axial mass. The mass exhibited the following MRI signal intensity characteristics: T2W mixed, T1W iso‐ to hypointense, FLAIR hyperintense, and strong contrast enhancement. The mass was removed with cavitronic ultrasonic surgical aspirator (CUSA) assisted neurosurgery. Based on histopathological appearance and immunohistochemistry, the diagnosis of inflammatory fibrosarcoma was made. To our knowledge, this is the first report describing MRI characteristics of intracranial inflammatory fibrosarcoma in the veterinary literature. 相似文献