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131.
Powerful relativistic jets are among the most ubiquitous and energetic observational consequences of accretion around supermassive black holes in active galactic nuclei and neutron stars and stellar-mass black holes in x-ray binary (XRB) systems. But despite more than three decades of study, the structure and composition of these jets remain unknown. Here we present spatially resolved x-ray spectroscopy of arc second-scale x-ray jets from XRB SS 433 analyzed with the Chandra advanced charge-coupled device imaging spectrometer. These observations reveal evidence for a hot continuum and Doppler-shifted iron emission lines from spatially resolved regions. Apparently, in situ reheating of the baryonic component of the jets takes place in a flow that moves with relativistic bulk velocity even more than 100 days after launch from the binary core.  相似文献   
132.
The aims of this pilot study were to evaluate the feasibility and efficacy of high-dose hypofractionated volumetric modulated arc radiotherapy (VMAT) applied to whole pelvic region radiotherapy (WPRT) with multilevel simultaneous integrated boost (MLSIB) combined with piroxicam and chemotherapy for the treatment of canine transitional cell carcinoma (TCC) of the lower urinary tract with muscle invasion TCC. Twelve dogs were enrolled, according to stage, in two groups: group 1, TCC confined to the urinary tract; group 2, TCC with metastasis. The planning target volume dose was tailored from 36 to 42 Gy in 6 fractions. All dogs were prescribed piroxicam and radiosensitizing carboplatin, and six received chemotherapy after radiotherapy. Serial follow-ups with computed tomography and magnetic resonance imaging were performed. Disease control and toxicity effects were evaluated according to the Response Evaluation Criteria in Solid Tumors and Veterinary Radiation Therapy Oncology Group criteria. The treatment was well tolerated, and no high-grade side effects were reported. The median overall survival times for groups 1 and 2 were 1,230 and 150 days, respectively. A considerable percentage of patients in group1 (50%) were still alive at the time of writing this paper, and a longer follow-up could enable a more accurate survival analysis. This preliminary analysis shows that VMAT applied to the WPRT with MLSIB is an effective and safe option for dogs with lower urinary TCC, although the presence of metastases worsens the prognosis.  相似文献   
133.
Burrito tea originates from the leaves of Wendita calysina, an indigenous Paraguayan plant, which is commonly consumed in South America and in Western countries. Phytochemical investigation of this species has led to the isolation of 14 constituents, among them 2 new flavanonols, dihydroquercetagetin (1) and 3,5,6,7,4'-pentahydroxyflavanonol (2), in addition to several known methoxyflavones, methoxyflavonols, phenylethanoid glycosides, and benzoic acid derivatives (4-14). All structures were elucidated by ESI-MS and NMR spectroscopic methods. Quantitative determination of phenolic constituents from burrito water infusions has been performed by HPLC-UV-DAD. The total antioxidant activity of the tea was measured by the ABTS(*)(+) radical cation decolorization and chemiluminescence (CL) assays and compared with the values of other commonly used herbal teas (green and black teas, mate, and rooibos).  相似文献   
134.
Rhizosphere processes involved in hyperaccumulation and exclusion of metals are still largely unknown. Therefore, we conducted a rhizobag experiment on contaminated and non‐contaminated soils to investigate the chemical changes in the rhizosphere of the hyperaccumulators Thlaspi goesingense and T. caerulescens, and the metal‐excluder T. arvense. Root growth was restricted to the rhizobags separated by a nylon membrane (7 μm \x 25 μm mesh size) from surrounding bulk soil. Depletion of labile Zn in rhizosphere could not explain the amount of metals accumulated in T. caerulescens, whereas the difference in EDTA‐extractable Zn even exceeded total plant uptake. Substantially increased DOC in T. arvense rhizosphere indicates alleviation of phytotoxicity by formation of metal‐organic complexes. Hyperaccumulation and depletion of labile Zn in the rhizosphere was observed for T. goesingense grown on contaminated soil. On non‐contaminated soil, Zn was accumulated but labile Zn in rhizosphere was not changed. Nickel present in background concentrations in both soils was accumulated by T. goesingense only when grown on non‐contaminated soil. In contrast, labile Ni in the rhizosphere was increased in both soils, suggesting a general tendency of Ni mobilization by T. goesingense.  相似文献   
135.
We investigated how vegetation features and temporal variation influenced web spider richness, abundance and composition along an edge between Araucaria forest and pasture in southern Brazil. Web spiders and vegetation were surveyed four times over a 1-year period, in five 5 × 5 m plots randomised in four locations: 50 m into the pasture, 0, 50 and 250 m into the forest. We collected a total of 836 web spiders (33 morphospecies and six families). We found different web spider assemblages occurring at the pasture edge and forest interior. The richness and abundance of web spiders decreased up to 50 m towards the forest interior in all seasons, and we found a positive influence of vegetation richness on web spider abundance. In conclusion, web spider assemblages are influenced by an edge gradient, this pattern is consistent throughout the year and is strongly related to vegetation features.  相似文献   
136.
The aortic arrangement is an important structure associated with the maintenance of homeostasis. Based on this information, this study was conducted to describe the collateral arteries of the aortic arch of Antillean manatee and define the standard model for the species. Three specimens, an adult male, adult female and a male neonate, all strandings on the coast of the state of Rio Grande do Norte, Brazil, were used. The study was performed in the Laboratory of Morphophysiology of Vertebrates of the Federal University of Rio Grande do Norte, where in situ photographs were taken to demonstrate their topography. Subsequently, their hearts were removed and fixed in 10% formaldehyde and after 72 hr were dissected and analysed, obtaining schematic drawings and photographs of the vascular arrangement. The aortic arch was represented by three collateral arteries identified as the brachiocephalic trunk, left common carotid artery and left subclavian artery. This arrangement was similar to that found for other sirenians, and yet, for other mammals like hooded seal, murine, margarita island capuchin, black-handed tamarin, Mongolian gerbil and human. The morphological similarity presented in this study with different species of mammals, including humans, may contribute valuable information from an evolutionary point of view.  相似文献   
137.
Four 2-month-old foals were presented to an equine hospital with acute kidney injury caused by Leptospira interrogans infection. Clinical signs were nonspecific and included lethargy, fever, and unwillingness to nurse. The most important hematologic and clinicopathologic findings were azotemia, anemia, thrombocytopenia, hyponatremia, and hypochloremia. The diagnosis was based on urinary real-time PCR, serology using a microscopic agglutination test, or both. The most important serovars involved were L. interrogans serogroup australis serovar Bratislava and Australis. Treatment consisted of IV fluid therapy and antimicrobial treatment. Renal replacement therapy with hemodiafiltration was performed in 1 of the foals. All foals survived to discharge. This report highlights the importance of early diagnosis and treatment in foals with acute kidney injury caused by L. interrogans infection.  相似文献   
138.
The objective of this study was to evaluate the coefficient of total tract apparent digestibility (CTTAD) of dietary nutrients, endogenous fat loss (EFL), dietary metabolizable energy (ME) content, coefficient of true digestibility (CTD) of fat and faecal parameters of dogs. A total of 16 puppies and 8 adult dogs were distributed according to a double Latin square experimental design. A basal diet was formulated, to which increasing levels (60, 120 and 180 g/kg) of poultry offal fat oil were added. EFL was estimated using hyperbolic and linear regression as a function of LW/day and dry matter (DM) intake, respectively, and the CTD of fat was calculated. The CTTAD of acid-hydrolysis ether extract (AHEE) and ME content increased as dietary poultry offal fat level increased both in adult dogs and in puppies (p < .05). The CTTAD of DM and crude protein were higher in adult dogs than in puppies. EFL was estimated by hyperbolic regression as y = 98.1094 − 13.6202/x and y = 99.1280 − 26.1366/x, where y = CTTAD of AHEE (%) and x = AHEE intake/kg BW, for adult dogs and puppies, respectively, which yielded EFL values of 138 and 262 mg AHEE per kg BW per day for adult dogs and puppies respectively. The EFL estimated by linear regression was 7.89 g and 8.97 g/kg DM intake for adult dogs and puppies respectively. The CTD estimated by both methodologies was higher in puppies than in adults (p < .05). Lower faecal DM and score, and higher ammonia production were obtained in puppies than adult dogs (p < .05). The results indicate good fat utilization and that fat digestibility is underestimated, as the CTTAD of AHEE does not take into account EFL, particularly at low-fat inclusion levels and in growing dogs, which have greater EFL than adult dogs.  相似文献   
139.
Phytoremediation is a helpful technique to remediate copper-contaminated areas. The aim of this study was to evaluate sunflower phytoremediation capacity in two vineyard copper-contaminated soils (Inceptisol and Mollisol) and a copper mining waste. Nutrient uptake, copper phytoaccumulation, translocation factor (TF), and bioaccumulation factor (BCF) of sunflower were evaluated after 57 days of growth. Plants grown in both the Mollisol and Inceptisol soils showed high plant height. Fresh biomass was high in the Mollisol in the shoots and roots and also demonstrated the highest values on the tolerance index (TI). The BCF after growth in all three of the copper contaminated soils as Inceptisol, Mollisol, and copper mining waste showed reduction of this index value to 0.19, 0.24, and 0.03, respectively against native soil (Mollisol under natural conditions (4.71). Sunflowers have some important characteristics such as high phytomass production, copper phytoaccumulation, and potential use to biofuel. Thus, sunflower is a potential candidate to phytoremediation of vineyard copper-contaminated soils.  相似文献   
140.
This study was designed to investigate growth performance in two sturgeon hybrids reared in two quadrangular floating cages moored in an artificial pond, representing the first experience of sturgeon culture performed at Southern Mediterranean latitudes. The research was carried out from December 2000 to July 2001 and tested the growth performance, feeding parameters and biometric relationships. The sturgeons were randomly collected from the cages on a monthly basis, and total length, standard length (SL) and wet weight (WW) were recorded. The specific daily growth rate (SGRW) as somatic WW, food conversion ratio and condition factor (CF) were calculated. Biometric relationships, as linear regression, were also calculated on SL and WW data. Both hybrids grew slowly from December to April, but faster during the warm months. The growth performance of the two hybrids seems to be influenced by variability of the environmental conditions and, for both fish groups, there was a strong correlation between water temperature and SGRW at temperatures below 25 °C. The CF (constantly below 1) was similar for both hybrids. The regression analysis for WW and SL calculated for the entire period showed a positive allometry for both hybrids, indicating that the fishes grew in weight at a greater rate than required to maintain constant body proportion.  相似文献   
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