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41.
M. A. Leal M. Joppert M. V. Licínio H. Evangelista J. Maldonado K. C. Dalia C. Lima C. V. Barros Leite S. M. Correa Geiza Medeiros K. Dias da Cunha 《Water, air, and soil pollution》2008,188(1-4):67-80
The aim of the present work is to characterize the local atmospheric emissions levels and compare them to the component derived from global pollution in a remote site at South Hemisphere (Admiralty Bay located at King George Island in Antarctic Peninsula). Airborne particles, snow and soil/sediments samples were analyzed. Local-produced atmospheric aerosol dispersion was estimated for metals originated by fossil fuel burning from the permanent scientific stations using a simplified Gaussian model. Validation of atmospheric dispersion was established by in situ measurements. Soluble and insoluble particles deposited in freshly snow and airborne particles were analyzed by PIXE (Particle Induced X-Ray Emission) for the determination of the elemental mass concentration and to obtain the Mass Median Aerodynamic Diameter (MMAD). The results showed significant correlation between the concentration of atmospheric aerosol and the freshly deposited particles in the snow, and permitted an estimate of the atmospheric snow deposition factor for K, Cu, Zn, Fe, Pb, and Ti. Results of long-term aerosol data compilation suggest that besides the local aerosol sources, the continental atmospheric transport of airborne particles is not significantly affected by the airborne particles produced by local human impacts at King George Island. 相似文献
42.
Diego Alves Peçanha MartaSimone Mendonça Freitas Marlene Evangelista Vieira Thaísa Capato Lima Ygor de Souza Gonçalves 《Journal of plant nutrition》2019,42(8):879-890
Acmella oleracea occurs in the Amazon forest and is widely consumed in regional cuisine and folk medicine. Many studies concerning its active principles are available, but few studies have been carried out regarding mineral nutrition. The aim of this study was to characterize deficiencies symptoms and nutritional content in Acmella oleracea. The experimental design applied was a randomized block with four replications. After blooming, following treatments were applied: complete solution, absence of Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, Sulfur, and Boron. After harvesting, growth and nutrient content of inflorescences, new leaves, old leaves, and stems were assessed. The absence of aforementioned nutrients allowed for characterization of visual deficiency symptoms. The first observed symptom was absence of Nitrogen. The accumulation of macronutrients in inflorescences followed the order N?>?K?>?Ca?>?P?>?S?>?Mg, in new leaves, N?>?K?>?Ca?>?S>Mg?>?P, in old leaves, K?>?N?>?Ca?>?Mg?>?S?>?P, and in stems K?>?N?>?Ca?>?Mg?>?P?>?S. The greatest growth restrictions were observed in nitrogen and calcium absence treatments. 相似文献
43.
F. Feng D. J. Myers M. P. Hojilla‐Evangelista K. A. Miller L. A. Johnson S. K. Singh 《Cereal Chemistry》2002,79(5):707-709
Sequential extraction processing (SEP) is a new approach to fractionating dried, flaked corn using 95% ethanol. In the original process, corn oil was extracted at 76°C in a countercurrent mode while simultaneously dehydrating the ethanol. This resulted in 20% of the protein (predominantly zein) coextracting with the oil. The process was modified to reduce the amount of coextracted protein. One modification (mSEP1) was to use a blend of 30% hexane and 70% ethanol at 56°C. A second modification (mSEP2) used a longer extraction column (L/D ratio 15) to replace the column with L/D 2 used in the original SEP system. To determine the effect of the modifications on oil quality, the quality of the crude corn oils produced from the modified SEP processes were compared with the quality of oil from the original SEP. To evaluate the quality of the three crude oils produced by SEP with the process typically used in industry, they were compared with the quality of laboratory hexane‐extracted corn oil. The results of the three SEP oils exhibited larger concentrations of fatty acids, phospholipids, and carotenoids, smaller concentrations of triacylglycerols, and darker red color than the hexane‐extracted oil. The oils from the two modified SEP processes contained smaller concentrations of free fatty acids and phospholipids and larger concentrations of triacylglycerols and carotenoids than the original SEP oil. In spite of the improvements to the oil through process modifications, the mSEP1 and mSEP2 oils exhibit greater refining losses than hexane‐extracted oil. 相似文献
44.
Nakage AP Santana AE de Cápua ML Godoy AV 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):394-399
BACKGROUND: Models for the study of hematopoietic stem cells in dogs provide important information for bone marrow transplantation in humans. Recent studies have reported the importance of human umbilical cord blood (UCB) as an alternative to allogenic bone marrow for hematopoietic reconstitution. However, there are no studies on the UCB cells of dogs. OBJECTIVE: The aim of this experiment was to characterize and quantify the blood cells of the umbilical cord of dogs. METHODS: The blood of the umbilical cord of 20 neonatal dogs, delivered at term, with a median gestation time of 58 days, was collected with a 5-mL syringe containing EDTA. Total RBC, WBC, and platelet counts, HCT, hemoglobin (Hgb) concentration, and RBC indices were determined using an automatic cell counter. The differential leukocyte count was determined manually in blood smears stained with May-Grünwald-Giemsa. Reticulocyte percentages were determined on blood smears stained with brilliant cresyl blue and counterstained with May-Grünwald Giemsa. RESULTS: The MCHC and numbers of RBCs, WBCs, neutrophils, and eosinophils in UCB were lower as compared with reference values for the peripheral blood of healthy neonatal and adult dogs; whereas, the MCV and reticulocyte percentages were higher. CONCLUSION: Erythrocyte macrocytosis and hypochromasia in UCB were consistent with marked reticulocytosis and indicative of high erythropoietic activity. The results of this study are an important first step in the characterization of UCB from neonatal dogs. 相似文献
45.
Elena Colombino Ilaria Biasato Elena Biasibetti Alessandra Sereno Laura Chiappino Rocchina Evangelista Giovanna Cenacchi Franco Guarda Maria Teresa Capucchio 《Anatomia, histologia, embryologia》2019,48(3):201-206
Anitschkow cells (AC) are a peculiar type of stromal cells observed in myocardium, cardiac valves and coronary vessels wall whose origin, characterization and role remain controversial. In human heart, they represent a histological hallmark of Aschoff nodules in rheumatic fever, but they have also been observed in other myocardial pathologies. Firstly, they have been considered a myocyte‐derived cells, but light microscopy, immunohistochemical and ultrastructural studies pointed out that a macrophagic/histiocytic origin cannot be excluded. Many authors also reported extracardiac AC or an Anitschkow nuclear pattern, thus suggesting that these cells may represent a chromatin pattern rather than a specific cell type. In veterinary medicine, AC were described in myocarditis, myocardial necrosis, degenerative and inflammatory endocardial diseases of several species. Recently, AC have been observed in intramural coronary arteries of different animals (including cattle and fish) affected by arteriosclerotic processes. Stress related to the intensive livestock farming could represent a mechanotransduction promoting factor of arteriosclerotic changes allowing the development of Anitschkow chromatin pattern. Further studies both in human and veterinary medicine are needed to confirm the origin and role of these peculiar cells. 相似文献
46.
CC Pérez‐Marín FD Requena A Arando L Requena F Requena EI Agüera 《Reproduction in domestic animals》2018,53(2):534-544
The aim of this study was to determine the effects of various abiotic factors, such as light, physical stress (pipetting) and thermal shock, on the quality of fresh and cooled equine sperm. In experiment I, four sperm aliquots were subjected to different light exposures: (i) protected control samples (CTRL), (ii) exposed to UV light at 10 cm (UV10), (iii) exposed to UV light at 20 cm (UV20) and (iv) exposed to laboratory lighting (LAB). In experiment II, four semen aliquots were subjected to repeated pipetting for 0, 10, 20 and 30 times (CTRL, P10, P20 and P30, respectively). In experiment III, four semen aliquots at 15°C were subjected to thermal oscillations: (i) cooled control sperm at 15°C (CTRL), (ii) oscillations of 1.9°C/min to a temperature of 30°C (T30), (iii) oscillations of 1.4°C/min, with the temperature rapidly falling until reaching 1.3°C (T0R) and (iv) oscillations of 1.1°C/min, with the temperature slowly falling until reaching 4.2°C (T0S). The results revealed that after 30 min, UV10 and UV20 sperm samples showed significantly (p < .05) lower total and progressive motility values, sperm kinematic parameters and mitochondrial potential. After 45 min of exposure, differences were highly significant (p < .001). No significant differences (p > .05) were found for pipetting or thermal oscillations. The results suggest that, even if equine sperm samples are not handled in the laboratory under optimal conditions, fresh and cooled equine spermatozoa are able to resist the impact of various abiotic stimuli without any reduction in their quality. This study analyses the effect on normospermic samples, but future research could look at the tolerance that asthenozoospermic equine samples have to these abiotic influences. 相似文献
47.
Brian P. Grossbard DVM Catherine A. Loughin DVM Diplomate ACVS ACCT Leonard J. Marino MD FAAP Joseph Sackman Scott E. Umbaugh BSE MSEE PhD Patrick S. Solt BSEE MSCS Jakia Afruz BSAPECE MSAPECE Peter Leando PhD DSc DAc Martin L. Lesser PhD EMT‐CC Meredith Akerman MS 《Veterinary surgery : VS》2014,43(7):869-876
48.
MR Luz CC de Holanda JJ Pereira PMC Freitas AEP Salgado J Di Giorgio Giannotti SB de Oliveira NS Teixeira CR de Freitas Guaitolini 《Reproduction in domestic animals》2011,46(4):724-727
The embryonic collection techniques in dogs present a vast methodological variation and low recovery rates. The objectives were to compare and describe two techniques as to the recovery of canine embryos, on the 12th day after the first mating or artificial insemination. Embryos were recovered through uterine horn flushing in vivo, before performing the ovariohysterectomy (OHE) (Group 1; n = 9) or ex vivo, immediately after the OHE (Group 2; n = 9). In total, 43 and 47 embryonic structures were recovered in Groups 1 and 2, respectively. There was no significant difference (p > 0.05) between groups on recovery rates (72.8% and 81.0%, respectively). We inferred that both in vivo and ex vivo techniques allow a high rate of embryonic recovery; in the collection technique prior to the OHE, it is essential to carefully handle the reproductive system during the trans‐surgical period and that the 12th day (D12) after the first mating/artificial insemination is an efficient option for the high recovery rate of morulae and blastocysts. 相似文献
49.
The kinetics of a first-order, solid-solid phase transition were investigated in the prototypical nanocrystal system CdSe as a function of crystallite size. In contrast to extended solids, nanocrystals convert from one structure to another by single nucleation events, and the transformations obey simple unimolecular kinetics. Barrier heights were observed to increase with increasing nanocrystal size, although they also depend on the nature of the nanocrystal surface. These results are analogous to magnetic phase transitions in nanocrystals and suggest general rules that may be of use in the discovery of new metastable phases. 相似文献
50.
A comparison of whole-genome shotgun-derived mouse chromosome 16 and the human genome 总被引:1,自引:0,他引:1
Mural RJ Adams MD Myers EW Smith HO Miklos GL Wides R Halpern A Li PW Sutton GG Nadeau J Salzberg SL Holt RA Kodira CD Lu F Chen L Deng Z Evangelista CC Gan W Heiman TJ Li J Li Z Merkulov GV Milshina NV Naik AK Qi R Shue BC Wang A Wang J Wang X Yan X Ye J Yooseph S Zhao Q Zheng L Zhu SC Biddick K Bolanos R Delcher AL Dew IM Fasulo D Flanigan MJ Huson DH Kravitz SA Miller JR Mobarry CM Reinert K Remington KA Zhang Q Zheng XH Nusskern DR Lai Z Lei Y Zhong W Yao A Guan P Ji RR Gu Z Wang ZY Zhong F 《Science (New York, N.Y.)》2002,296(5573):1661-1671
The high degree of similarity between the mouse and human genomes is demonstrated through analysis of the sequence of mouse chromosome 16 (Mmu 16), which was obtained as part of a whole-genome shotgun assembly of the mouse genome. The mouse genome is about 10% smaller than the human genome, owing to a lower repetitive DNA content. Comparison of the structure and protein-coding potential of Mmu 16 with that of the homologous segments of the human genome identifies regions of conserved synteny with human chromosomes (Hsa) 3, 8, 12, 16, 21, and 22. Gene content and order are highly conserved between Mmu 16 and the syntenic blocks of the human genome. Of the 731 predicted genes on Mmu 16, 509 align with orthologs on the corresponding portions of the human genome, 44 are likely paralogous to these genes, and 164 genes have homologs elsewhere in the human genome; there are 14 genes for which we could find no human counterpart. 相似文献