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991.
Mycobacterium marinum isolates cultivated from tissue containing granulomatous lesions in Florida pompano Trachinotus carolinus and from biofilm samples collected from their tank and water recirculating system had identical (L1 of 11 bands) repetitive-sequence-based polymerase chain reaction (rep-PCR) DNA fingerprints. A second M. marinum clone sharing 4 of 11 rep-PCR bands with the first clone was isolated from some fish tissues but not from system samples. Water samples yielded low numbers of colonies of mycobacteria (0.08-1.3/mL), but high numbers were recovered from biofilms (260-12,000/swab) and filters (63-21,000/ filter). Mycobacterium hemophilum, M. chelonae, M. trivale, M. gastri, and M. gordonae were isolated from system samples alone. 相似文献
992.
Marchitto TM Muscheler R Ortiz JD Carriquiry JD van Geen A 《Science (New York, N.Y.)》2010,330(6009):1378-1381
We present a high-resolution magnesium/calcium proxy record of Holocene sea surface temperature (SST) from off the west coast of Baja California Sur, Mexico, a region where interannual SST variability is dominated today by the influence of the El Ni?o-Southern Oscillation (ENSO). Temperatures were lowest during the early to middle Holocene, consistent with documented eastern equatorial Pacific cooling and numerical model simulations of orbital forcing into a La Ni?a-like state at that time. The early Holocene SSTs were also characterized by millennial-scale fluctuations that correlate with cosmogenic nuclide proxies of solar variability, with inferred solar minima corresponding to El Ni?o-like (warm) conditions, in apparent agreement with the theoretical "ocean dynamical thermostat" response of ENSO to exogenous radiative forcing. 相似文献
993.
Identification of anisotropic vibrational properties of Padauk wood with interlocked grain 总被引:1,自引:0,他引:1
Iris Brémaud Pierre Cabrolier Joseph Gril Bruno Clair Jean Gérard Kazuya Minato Bernard Thibaut 《Wood Science and Technology》2010,44(3):355-367
Grain deviations and high extractives content are common features of many tropical woods. This study aimed at clarifying their
respective impact on vibrational properties, referring to African Padauk (Pterocarpus soyauxii Taub.), a species selected for its interlocked grain, high extractives content and uses in xylophones. Specimens were cut
parallel to the trunk axis (L), and local variations in grain angle (GA), microfibril angle (MFA), specific Young’s modulus
(E′
L
/ρ, where ρ stands for the density) and damping coefficient (tanδL) were measured. GA dependence was analysed by a mechanical model which allowed to identify the specific Young’s modulus (E′3/ρ) and shear modulus (G′/ρ) along the grain (3) as well as their corresponding damping coefficients (tanδ3, tanδG). This analysis was done for native and then for extracted wood. Interlocked grain resulted in 0–25° GA and in variations
of a factor 2 in E′L/ρ and tanδL. Along the grain, Padauk wood was characterized, when compared to typical hardwoods, by a somewhat lower E′3/ρ and elastic anisotropy (E′/G′), due to a wide microfibril angle plus a small weight effect of extracts, and a very low tanδ3 and moderate damping anisotropy (tanδG/tanδ3). Extraction affected mechanical parameters in the order: tanδ3 ≈ tanδG > G′/ρ > > E′3/ρ. That is, extractives’ effects were nearly isotropic on damping but clearly anisotropic on storage moduli. 相似文献
994.
Snags are important both as structural components and as animal habitat in forests, but abundance is often low and their dynamics poorly understood in young, managed stands. Using a large data set of 19,622 snags from permanent plots in second-growth forests of coastal British Columbia, we modeled snag longevity (time from tree mortality to snag fall) for three species: Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), and western redcedar (Thuja plicata). Snag longevity was strongly related to species and snag size (diameter): the median snag longevity was 16 years for Douglas-fir, 11 years for hemlock and 5 years for redcedar. Western redcedar was predominantly in the subcanopy and its rapid fall rate was related to the small size of its snags. In addition to diameter, other attributes (height to diameter ratio, height, and live crown ratio before death) contributed significantly to models for one or two of the species. However, site level variables did not contribute significantly to any of the models. Snags greater than 50 cm diameter, especially Douglas-fir snags, have the potential for persistence well beyond 20 years in these second-growth forests, and could be important for wildlife. 相似文献
995.
996.
David W. Hunley G. Neal Mauldin Keijiro Shiomitsu Glenna E. Mauldin 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(3):293-300
Intensity-modulated radiation therapy (IMRT) is a valuable tool in human radiation oncology, but information on its use in veterinary medicine is lacking. In this study, 12 dogs with nasal tumors were treated with IMRT at a median radiation dose of 54 Gy. Patient survival times and frequency and severity of side effects on ocular structures, oral mucosa, and skin were recorded. Eight dogs (67%) had resolution of clinical signs during radiation therapy. Median overall survival time was 446 d with a 50% 1-year and a 25% 2-year survival rate. Minimal grade 2 or 3 acute skin toxicity, no grade 2 or 3 late skin toxicity, and no grade 2 or 3 toxicity to oral mucosa or the eye opposite the tumor were identified in the dogs treated with IMRT in this study. The ipsilateral eye could not be routinely spared due to its proximity to the tumor. 相似文献
997.
Watanabe S Omatsu T Miranda ME Masangkay JS Ueda N Endo M Kato K Tohya Y Yoshikawa Y Akashi H 《Comparative immunology, microbiology and infectious diseases》2010,33(1):25-36
To reveal whether bats serve as an amplifying host for Yokose virus (YOKV), we conducted a serological survey and experimentally infected fruit bats with YOKV isolated from microbats in Japan. YOKV belongs to the Entebbe bat virus group of vector unknown group within the genus Flavivirus and family Flaviviridae. To detect antibodies against YOKV, we developed an enzyme-linked immunosorbent assay (ELISA) using biotinylated anti-bat IgG rabbit sera. Serological surveillance was conducted with samples collected in the Philippines and the sera supplied from Malaysia. One of the 36 samples from the Philippines (2.7%) and 5 of the 26 samples from Malaysia (19%) had detectable ELISA antibodies. In the experimental infections, no clinical signs of disease were observed. Moreover, no significant viral genome amplification was detected. These findings revealed that YOKV replicates poorly in the fruit bat, suggesting that fruit bats do not seem to serve as an amplifying host for YOKV. 相似文献
998.
Kajal Chakraborty Deepu Joseph Selsa Jose Chakkalakal 《Journal Of Aquatic Food Product Technology》2013,22(4):568-584
ABSTRACTSeasonal variations (premonsoon, monsoon, and postmonsoon) of the lipid, fatty acid, and total cholesterol profile in edible tissues of Sardinella longiceps collected from the southwest and southeast coasts of India over 4 yr (2008–2011) were studied. The correlation between the fatty acid composition with chlorophyll-a concentration, sea surface temperature, total phytoplankton density, diatom concentration, and fatty acid profiles of pooled stomach microalgal content were also evaluated. Significant correlation was observed between oil sardine and pooled stomach microalgal content polyunsaturated fatty acids along with chlorophyll-a concentration, especially during the monsoon at the southwest coast and monsoon and postmonsoon at the southeast coast of the Indian subcontinent. Similarly, the health indices such as atherogenic index, thrombogenicity index, total cholesterol, and hypocholesterolemic/hypercholesterolemic ratio of oil sardine were found to be ideal, which contributed toward its parameters to be qualified as an ideal health food. 相似文献
999.
Martin Bencsik Joseph BencsikMichael Baxter Andrei LucianJulien Romieu Mathias Millet 《Computers and Electronics in Agriculture》2011,76(1):44-50
Honey bees live in groups of approximately 40,000 individuals and go through their reproductive cycle by the swarming process, during which the old queen leaves the nest with numerous workers and drones to form a new colony. In the spring time, many clues can be seen in the hive, which sometimes demonstrate the proximity to swarming, such as the presence of more or less mature queen cells. In spite of this the actual date and time of swarming cannot be predicted accurately, as we still need to better understand this important physiological event. Here we show that, by means of a simple transducer secured to the outside wall of a hive, a set of statistically independent instantaneous vibration signals of honey bees can be identified and monitored in time using a fully automated and non-invasive method. The amplitudes of the independent signals form a multi-dimensional time-varying vector which was logged continuously for eight months. We found that combined with specifically tailored weighting factors, this vector provides a signature highly specific to the swarming process and its build up in time, thereby shedding new light on it and allowing its prediction several days in advance. The output of our monitoring method could be used to provide other signatures highly specific to other physiological processes in honey bees, and applied to better understand health issues recently encountered by pollinators. 相似文献
1000.
Emmanuel Joseph Rupia Jiaojiao Shen Jiamin Wu Wenyin Chen Liping Liu Kristof Dierckens Patrick Sorgeloos Weiqun Lu 《Aquaculture International》2014,22(3):1105-1120
Two groups of Anguilla japonica were treated with hormone, one on a weekly basis, the other on a biweekly basis. Intramuscular injection was applied at a dose of 0.75 mg/kg BW carp pituitary extract (CPE) plus 150 IU/kg BW human chorionic gonadotropin (hCG) for female fish, while males received half of this dose. The average total lipid content of the gonads from the weekly treated group, i.e. 20.6 ± 1.2 % for females and 18.0 ± 2.3 % for males, was significantly higher than the biweekly treated group, 16.8 ± 0.7 and 15.5 ± 1.3 %, respectively (p < 0.05). For both muscle and liver, the readings were not significantly different. The gonads from the weekly treated fish had more fatty acids, particularly saturated fatty acids, polyunsaturated fatty acids, highly unsaturated fatty acids, eicosapentaenoic acid (20:5n-3, EPA), docosahexaenoic acid (22:6n-3, DHA) and arachidonic acid (20:4n-6, ARA). Histological examination showed that the ovaries of both the weekly and the biweekly treated fish were mainly at stage IV. However, the weekly treated females had bigger oocyte diameter (722.0 ± 60.9 μm) than the biweekly females (611.6 ± 22.6 μm). These results suggest that CPE and hCG promoted the maturation process for both scheduled induction and that the frequency of hormone injection influenced the biochemical composition of gonads, especially their lipids. Our study describes for the first time the effect of hormone injection frequency on the lipid content and fatty acid composition in the gonads of A. japonica during artificial maturation. 相似文献