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31.
Billard Antoine Bauer Rodolphe Mothe Frédéric Colin Francis Christine Deleuze Longuetaud Fleur 《European Journal of Forest Research》2021,140(6):1401-1416
European Journal of Forest Research - Studies on wood basic density (BD) vertical variations become essential to predict more accurately the within-stem distributions of biomass and wood quality in... 相似文献
32.
Acanthocephalan and spargana parasites were identified within a body wall mass during exploratory surgery in a wild green tree snake. Acanthocephalan parasites have not previously been reported in this species. Surgical excision, the treatment of choice, could not be achieved because of the extensive infiltration of the coelomic cavity. 相似文献
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Andrea Ganthaler Helmut Bauer Andreas Gruber Michaela Mayr Walter Oberhuber Stefan Mayr 《European Journal of Forest Research》2014,133(2):201-211
Norway spruce trees in the subalpine forests of the European Alps are frequently attacked by the needle rust Chrysomyxa rhododendri. The obligate parasite undergoes a complex life cycle with a host shift between rhododendrons (Rhododendron sp.) and Norway spruce [Picea abies (L.) Karsten] and causes a yellowing and defoliation of the current-year needles in summer. Infected trees show several anatomical, morphological and physiological modifications, including a decrease in pigment content and net photosynthesis of infected needles, lower biomass production and reduced radial and height growth. The consequences are diminished timber yield and cripple growth. Because of repeated heavy infections in recent years, forest managers report increasing difficulties in both natural regeneration and afforestation at high elevation sites, where rhododendrons occur. This review gives a summary of the present knowledge about the effects of C. rhododendri infections on Norway spruce, including so far unpublished findings and with particular attention to the phenomena of resistant trees. Implications for subalpine forests and counter strategies are discussed. 相似文献
35.
Meg D. Sislak Kathy A. Spaulding Debra L. Zoran John E. Bauer James A. Thompson 《Veterinary radiology & ultrasound》2014,55(2):195-201
Echoes are frequently seen in the urinary bladder of cats during abdominal ultrasound. These have been attributed to hematuria, pyuria, crystalluria, and lipid. However, sonographic findings have not been previously correlated with urinalysis. We prospectively evaluated 40 clinically normal cats via ultrasound, serum chemistry, and urinalysis. Thin layer chromatography was performed on the urine to determine the amount (mg) of lipid subfractions including diacylglycerol, triglyceride, phospholipid, free fatty acid, cholesterol, and cholesterol ester. Ninety percent (36/40) of the cats in our population had sonographic echoes suspended in the urinary bladder, with most having a subjective score of mild echoes (n = 20). None of the sonographic echoes were gravity dependent or caused distal acoustic shadowing, reverberation, or twinkle artifact. Of the cats with sonographic echoes in the urine, 66% (24/36) had no significant findings on urinalysis other than the presence of lipid. The total amount of subjective sonographic echoes was not significantly related to the total amount of fat measured on thin layer chromatography or the number of lipid droplets seen on urinalysis. An increased amount of urine diacylglycerol was significantly associated with clumping of echoes (P = 0.02) and the amount of lipid droplets seen on urinalysis (P = 0.04). An association between increased amounts of urine diacylglycerol and the amount of echoes seen on ultrasound approached significance (P = 0.05). Findings from this study support previously published theories that sonographic echoes within the urinary bladder of clinically normal cats may be due to urine lipid. 相似文献
36.
Naití A. Morales Maike Heidemeyer Robert Bauer Sebastian Hernández Enzo Acuña Simon Jan van Gennip Alan M. Friedlander Carlos F. Gaymer 《水产资源保护:海洋与淡水生态系统》2021,31(2):340-355
- Marine protected areas (MPAs) are becoming a widely used tool for the conservation of biodiversity and for fishery management; however, most of these areas are designed without prior knowledge of the basic ecological aspects of the species that they are trying to protect.
- This study investigated the movement of two top predators: the Galapagos shark, Carcharhinus galapagensis, and the yellowtail amberjack, Seriola lalandi, in and around the Motu Motiro Hiva Marine Park (MMHMP) using MiniPAT satellite tags to determine the effectiveness of this MPA for the protection of these species.
- The Galapagos sharks (n = 4) spent most of their tag deployment periods inside the MMHMP. However, high intraspecific variability was observed in their movement dynamics. Daily individual maximum movements ranged from 17 to 58 km and the maximum distance from Salas y Gómez Island, the only emergent island within the MMHMP, ranged from 31 to 139 km.
- The maximum linear distance travelled for a female juvenile Galapagos shark (152 cm total length) was 236 km, which is greater than the maximum distance previously documented for juveniles of this species (<50 km).
- For the yellowtail amberjack (n = 1), 91% of the satellite geolocations were within the MMHMP, with a maximum daily distance travelled of 6 km. The maximum distance travelled between points was 111 km and the maximum distance from Salas y Gómez Island was 62 km.
- All archival tagged fish spent most of their time at depths of <50 m and never left the epipelagic zone. Daytime versus night-time differences were pronounced in all individuals but showed high interindividual variability.
- This study provides a baseline on the movement of these two top predators in the MMHMP and provides valuable insights for the creation of MPAs in the region and elsewhere.
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Adsorption of the mycotoxin ochratoxin A by activated charcoal, various bentonites (acid, alkaline, neutral), and hydrated sodium calcium aluminosilicate was tested in vitro as well as in feeding experiments with pigs. In vitro tests showed that the 1% addition of activated charcoal leads to complete adsorption of ochratoxin A from aqueous solutions. This effect was not influenced by pH-values ranging from 3-8. In contrast, adsorption by bentonite and hydrated sodium calcium aluminosilicate occurred primarily in the acid range (pH 3-4). Dietary addition of hydrated sodium calcium aluminosilicate (1%) and acid bentonite (1%, 10%) to ochratoxin A-contaminated feed (1.0 mg/kg) had no effect on the blood or tissue levels of the toxin in pigs. The addition of 1% activated charcoal caused a slight decrease of ochratoxin A in the blood, whereas a tenfold dosage resulted in a 50% to 80% reduction of ochratoxin A levels in both blood and tissue. Reduction of ochratoxin A absorption via the dietary administration of activated charcoal (5%) was confirmed in a 16 week feeding experiment. However, this experiment also showed the serum level of vitamin E to be lower than in the controls receiving adsorbent-free feed. 相似文献
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Prospects for hybrid breeding in winter triticale: II. Relationship between parental genetic distance and specific combining ability 总被引:1,自引:0,他引:1
Significant relative midparent heterosis (MPH%) for grain yield in triticale (×Triticosecale Wittm.) has generated interest in the development of hybrid cultivars. The objectives of this study were to (i) examine the association between parental genetic distance (GD) and specific combining ability (SCA), (ii) investigate the existence of genetically distant heterotic groups in elite germplasm, and (iii) draw conclusions for future hybrid breeding in winter triticale. Genetic distance between 61 lines was estimated, based on 93 polymorphic simple sequence repeat (SSR) marker loci and 10 AFLP (amplified fragment length polymorphism) primer‐enzyme combinations (PEC). Agronomic data of 206 F1 crosses and their 61 parental lines grown in six German environments were published recently in a companion study. Correlations were made between SCA for grain yield, number of spikes/m2, 1000‐kernel weight and number of kernels per spike with GD estimates of the 56 female and five male parents (testers). Principal co‐ordinate analyses (PCoA) based on SSR data revealed no distinct subgroups in the germplasm. Correlations between GD and SCA were low for all traits (|r| ≤ 0.31), which hampers the prediction of SCA from molecular data. A multi‐stage procedure is recommended for future hybrid breeding in triticale by applying a pragmatic approach for the grouping of germplasm following the early history of hybrid breeding of maize. 相似文献