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41.
KENTARO HONDA ALISTAIR J. HOBDAY RYO KAWABE NAOKI TOJO KO FUJIOKA YOSHIMI TAKAO KAZUSHI MIYASHITA 《Fisheries Oceanography》2010,19(2):151-158
Juvenile southern bluefin tuna (Thunnus maccoyii, SBT) were monitored in nearshore waters off southwest Australia using acoustic tagging and monitoring over five austral summers (2002/2003–2006/2007) to determine patterns in age‐based distribution of SBT. A total of 20–70 receivers were deployed in early December along one to three cross‐shelf transects and at three inshore topographic features (lumps) where SBT are known to occur; and a total of 59–84 juvenile SBT (41–90 cm fork length) were tagged and released each year. After several months, receivers were recovered, and data extracted. In 2002/2003 and 2003/2004, 2‐yr‐old SBT were detected more frequently in nearshore areas than did 1‐yr old fish. Similarly in 2004/2005 and 2006/2007, it was the larger 1‐yr‐old SBT that were detected more frequently at inshore lumps (>85% of detections) while small 1‐yr‐old SBT were detected more widely over the study area. In 2005/2006, although large 1‐yr‐old SBT were still detected more frequently at inshore lumps than small 1‐yr old SBT, the percentage of all detections at lumps was lower at 31.5%, indicating wider distribution of both small and large age‐1 fish. The observed age‐dependent distribution pattern may be enhanced by the distribution of prey, which disperse or concentrate depending on the local oceanography. 相似文献
42.
This article analyses motivations and attitudes of small-scale forest owners in the Czech Republic towards joining associations. The research is a follow-up to a field investigation performed within the National Forest Programme II for 2007–2013 in the Vyso?ina region in 2010. The present research was carried out in the Pilsen region in 2012 and the Central Bohemia region in 2015, applying the same method of investigation as in 2010—a questionnaire survey. The findings are based on the results of all three surveys and supported by the analysis of legal and forestry-related documents concerning financial subsidies for forest owners’ associations. The study has revealed reluctance of small-scale owners to join associations. Their lack of motivation is caused by insufficient funding from the government supporting the administration and management of associations. The reluctance also results from the request for associations to be legal entities, which most applicants do not meet as they are either not registered or are registered under unsuitable legal forms. Between 2011 and 2013, no contributions were paid by the government to associations, and no new small-scale forest owners’ associations were formed. To increase associations, we propose that the government should provide sufficient funding not only for the administration and management of associations but also for the process of establishing associations and initial investments. It is also necessary to make major innovations in legislature regarding the transition of ownerships to more convenient legal forms. 相似文献
43.
Miren del Río Hans Pretzsch Iciar Alberdi Kamil Bielak Felipe Bravo Andreas Brunner Sonia Condés Mark J. Ducey Teresa Fonseca Nikolas von Lüpke Maciej Pach Sanja Peric Thomas Perot Zahera Souidi Peter Spathelf Hubert Sterba Martina Tijardovic Margarida Tomé Patrick Vallet Andrés Bravo-Oviedo 《European Journal of Forest Research》2016,135(1):23-49
44.
Plavec Jelena Križanac Ivana Budinšćak Željko Škorić Dijana Musić Martina Šeruga 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):591-601
European Journal of Plant Pathology - Uncultivable bacteria from the genus ‘Candidatus Phytoplasma’ are associated with grapevine yellows (GY) diseases worldwide. In Euro-Mediterranean... 相似文献
45.
Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study 下载免费PDF全文
Angela Boggero Alberto Basset Martina Austoni Enrico Barbone Luca Bartolozzi Isabella Bertani Alessandro Campanaro Antonella Cattaneo Fabio Cianferoni Giuseppe Corriero Ambrosius Martin Dörr A. Concetta Elia Gentile Francesco Ficetola Lyudmila Kamburska Gianandrea La Porta Sara Lauceri Alessandro Ludovisi Elda Gaino Enzo Goretti Massimo Lorenzoni Marina Manca Aldo Marchetto Giuseppe Morabito Francesco Nonnis Marzano Alessandro Oggioni Cataldo Pierri Nicoletta Riccardi Giampaolo Rossetti Nicola Ungaro Pietro Volta Silvia Zaupa Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852
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46.
Martina Carrete Jos L. Tella Guillermo Blanco Marcelo Bertellotti 《Biological conservation》2009,142(10):2002-2011
Population growth and human development result in biodiversity loss and biological homogenization not only in developed countries, but increasingly in the less developed countries as well. In those countries, where urbanization and agricultural intensification occur at a faster rate than in developed countries, habitat degradation appears to be the leading cause of wildlife loss. During the breeding seasons of 2002–2005 we conducted road surveys across five biomes of Argentina to detect variations in raptor community attributes as potential indicators of broad scale habitat degradation. Abundance of individuals, richness and diversity of species were calculated to assess the effects of habitat transformation and patch size on these community attributes. Raptor communities strongly varied in relation to habitat transformations, with lower abundance of individuals, richness and diversity of species in more transformed landscapes. Small patches of natural vegetation and locations in which natural and cultivated lands where interspersed showed lower richness and diversity of raptors than large patches. Fragmentation was the main cause of reductions in abundance of individuals. Although the relative contribution of our two estimates of habitat degradation to abundance, richness and diversity of raptors varied among biomes, these community attributes proved useful as predictors of habitat degradation. This was especially true in habitats where raptor communities are more complex although overall patterns remained constant across biomes, from forests to deserts. Taking into account current trends of habitat transformation (drastic increments in monocultures, urban areas, and habitat patchiness), the conservation of raptor communities in these biomes could be seriously compromised. In terms of species-specific responses of raptors to habitat degradation, a rapid process of homogenization can be expected, resulting in only a few winner species within a general scenario of losers. 相似文献
47.
HIDEYUKI KANEMOTO KOICHI OHNO KO NAKASHIMA MASASHI TAKAHASHI YASUHITO FUJINO RYOHEI NISHIMURA HAJIME TSUJIMOTO 《Veterinary radiology & ultrasound》2009,50(2):188-194
Contrast-enhanced ultrasound using Sonazoid, a novel contrast medium with a liver-specific Kupffer phase, was evaluated in canine focal liver lesions Twenty-five dogs with a liver mass were given intravenous Sonazoid, and the enhancement pattern in the arterial, portal, and parenchymal phase was characterized. An enhancement defect in the lesion in the parenchymal phase was observed in all malignant lesions, whereas only one of nine benign lesions had a filling defect. The diagnostic value of the presence of a filling defect for malignancy was statistically significant (100% sensitivity, 88.9% specificity, 94.1% positive predictive value, 100% negative predictive value), and was equal to that of hypoenhancement in the portal or delayed phase. The defect pattern (clear or irregular defect) was dependent ( P <0.05) on the types of malignancy (i.e., hepatocellular carcinoma and other types of malignancies). In the arterial phase, five of the six hepatocellular carcinomas had hypervascularity, whereas no other lesion was characterized by hypervascularity. In some dogs, additional lesions that could not be observed with conventional B-mode ultrasonography were detected in the parenchymal phase. The enhancement pattern of Sonazoid, especially in the parenchymal phase, has potential as a diagnostic tool for canine focal liver lesions. 相似文献
48.
BYEONG-TECK KANG KI-JIN KO DONG-PYO JANG JAE-YONG HAN CHAE-YOUNG LIM CHUL PARK JONG-HYUN YOO JU-WON KIM DONG-IN JUNG YOUNG-BO KIM EUNG-JE WOO ZANG-HEE CHO HEE-MYUNG PARK 《Veterinary radiology & ultrasound》2009,50(6):615-621
The purpose of this study was to describe relevant canine brain structures as seen on T2-weighted images following magnetic resonance (MR) imaging at 7 T and to compare the results with imaging at 1.5 T. Imaging was performed on five healthy laboratory beagle dogs using 1.5 and 7 T clinical scanners. At 1.5 T, spin echo images were acquired, while gradient echo images were acquired at 3 T. Image quality and conspicuity of anatomic structures were evaluated qualitatively by direct comparison of the images obtained from the two different magnetic fields. The signal-to-nose ratio (SNR) and contrast-to-noise ratio (CNR) were calculated and compared between 1.5 and 7 T. The T2-weighted images at 7 T provided good spatial and contrast resolution for the identification of clinically relevant brain anatomy; these images provided better delineation and conspicuity of the brain stem and cerebellar structures, which were difficult to unequivocally identify at 1.5 T. However, frontal and parietal lobe and the trigeminal nerve were difficult to identify at 7 T due to susceptibility artifact. The SNR and CNR of the images at 7 T were significantly increased up to 318% and 715% compared with the 1.5 T images. If some disadvantages of 7 T imaging, such as susceptibility artifacts, technical difficulties, and high cost, can be improved, 7 T clinical MR imaging could provide a good experimental and diagnostic tool for the evaluation of canine brain disorders. 相似文献
49.
Lecchi C Avallone G Giurovich M Roccabianca P Ceciliani F 《Veterinary journal (London, England : 1997)》2009,180(2):256-258
Combined quantitative (real-time) polymerase chain reaction and immunohistochemistry were used to evaluate the expression of the minor acute phase protein alpha 1-acid glycoprotein (AGP, orosomucoid) in bovine extrahepatic tissues. AGP was produced mainly in the salivary glands and spleen, whereas minor expression was detected in all other tissues sampled, including lung, lymph nodes, uterus, ovary, kidney and tongue. The findings were consistent with immunohistochemical results. In view of the immunomodulatory and direct antibacterial activity of AGP, its expression in the salivary glands may signal an involvement in the regulation of the local immunity, even in non-pathological conditions. 相似文献
50.
Ingolf Profft Martina Mund Georg-Ernst Weber Eberhard Weller Ernst-Detlef Schulze 《European Journal of Forest Research》2009,128(4):399-413
Wood products are considered to contribute to the mitigation of carbon dioxide emissions. A critical gap in the life cycle
of wood products is to transfer the raw timber from the forest to the processing wood industry and, thus, the primary wood
products. Therefore, often rough estimates are used for this step to obtain total forestry carbon balances. The objectives
of this study were (1) to examine the fate of timber harvested in Thuringian state forests (central Germany), representing
a large, intensively managed forested region, and (2) to quantify carbon stocks and the lifetime of primary wood products
made from this timber. The analyses were based on the amount and assortments of actually sold timber, and production parameters
of the companies that bought and processed this timber. In addition, for coniferous stands of a selected Thuringian forest
district, we calculated potential effects of management, as expressed by different thinning regimes on wood products and their
lifetimes. Total annual timber sale of soft- and hardwoods from Thuringian state forests (195,000 ha) increased from about
136,893 t C (~0.7 t C ha−1 year−1) in 1996 to 280,194 t C (~1.4 t C ha−1 year−1) in 2005. About 47% of annual total timber harvest went into short-lived wood products with a mean residence time (MRT) < 25
years. Thirty-one per cent of the total harvest went into wood products with an MRT of 25–43 years, and only 22% was used
as construction wood and glued wood, products with the longest MRT (50 years). The average MRT of carbon in harvested wood
products was 20 years. Thinning from above throughout the rotation of spruce forests would lead to an average MRT in harvested
wood products of about 23 years, thinning from below of about 18 years. A comparison of our calculations with estimates that
resulted from the products module of the CO2FIX model (Nabuurs et al. 2001) demonstrates the influence of regional differences in forest management and wood processing industry on the lifetime of
harvested wood products. To our knowledge, the present study provides for the first time real carbon inputs of a defined forest
management unit to the wood product sector by linking data on raw timber production, timber sales and wood processing. With
this new approach and using this data, it should be possible to substantially improve the net-carbon balance of the entire
forestry sector. 相似文献