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71.
A comparative study of apple and pear tree water consumption measured with two weighing lysimeters 总被引:1,自引:1,他引:0
Joan Girona Jesus del Campo Merce Mata Gerardo Lopez Jordi Marsal 《Irrigation Science》2011,29(1):55-63
A five-year experiment (2002–2006) was conducted to determine apple (cv ‘Golden Smoothee’) and pear (cv ‘Conference’) crop
coefficients (Kc) using two large weighing lysimeters. Daily reference evapotranspiration (ETo) and crop evapotranspiration
(ETc) were evaluated. Midday canopy light interception of both crops planted in hedgerows, 4 × 1.6 m, was determined on a
weekly basis from bud-break until leaf fall from year 2002 (fourth after planting) to year 2006 of both plantations. Relationships
between canopy light interception and calculated Kc (ETc/ETo) were evaluated from bud-break until harvest. There were differences
in Kc values between apple and pear trees. When daily Kc values from bud-break until harvest were adjusted to hyperbolic functions
each year, adjusted curves for pear trees were very similar regardless of year (maximum Kc around 1.0). In apple trees, the
maximum values of Kc increased over time, from 0.49 in 2002 to 1.04 in 2006. Midday light interception in both apple and pear
trees increased during the 5 years of experiment from 29.0 to 45.6% in apples and from 27.5 to 41.6% in pears in midsummer.
Although there was a significant positive correlation between midday canopy light interception and Kc in apple and pear trees,
in different times within a specific year, these relationships were different between crops. While the apple data fitted into
the same equation regardless of the year, different equations were needed to fit the pear data in different years. This discrepancy
may have been related to differences in the canopy properties between apple and pear trees. Pear canopies had higher porosity
than apple canopies and thus improved light penetration. Apple trees were more vigorous and produced taller and denser canopies.
Pear Kc values were greatly influenced by the evaporative demands of different years and consequently differences in midday
canopy light interception did not adequately reflect the differences in Kc across the two species. 相似文献
72.
Tritrichomonas foetus is the causative agent of sexually transmitted trichomoniasis in cattle. In females, the infection can be associated with infertility, vaginitis, endometritis, abortion or pyometra, leading to significant economic losses in cattle raising. T. foetus is devoid of the ability to synthesize purine nucleotides de novo, depending instead on salvaging purines from the host environment. Ecto-5'-nucleotidase catalyzes the final step of extracellular nucleotide degradation, the hydrolysis of nucleoside 5'-monophosphates to the corresponding nucleosides and Pi. In this work we show that living, intact cells of T. foetus were able to hydrolyze 5'AMP at a rate of 12.57 ± 1.23 nmol Pi × h(-1) × 10(-7) cells at pH 7.2 and the 5'AMP hydrolysis is due to a plasma membrane-bound ecto-enzyme activity. The apparent K(m) for 5'AMP was 0.49 ± 0.06 mM. In addition to 5'AMP, the enzyme hydrolyzed all substrate monophosphates tested except 3'AMP. No divalent metals or metal chelators were able to modulate enzyme activity. Phosphatase inhibitors did not have an effect on ecto-5'-nucleotidase activity while ammonium molybdate did inhibit the activity in a dose dependent manner. The presence of adenosine in the culture medium negatively modulated the enzyme. These results indicate the existence of an ecto-5'-nucleotidase that may play a role in the salvage of purines. 相似文献
73.
Lozano-Sánchez J Giambanelli E Quirantes-Piné R Cerretani L Bendini A Segura-Carretero A Fernández-Gutiérrez A 《Journal of agricultural and food chemistry》2011,59(21):11491-11500
Phenolic compounds in extra virgin olive oil (EVOO) have been associated with beneficial effects for health. Indeed, these compounds exert strong antiproliferative effects on many pathological processes, which has stimulated chemical characterization of the large quantities of wastes generated during olive oil production. In this investigation, the potential of byproducts generated during storage of EVOO as a natural source of antioxidant compounds has been evaluated using solid-liquid and liquid-liquid extraction processes followed by rapid resolution liquid chromatography (RRLC) coupled to electrospray time-of-flight and ion trap mass spectrometry (TOF/IT-MS). These wastes contain polyphenols belonging to different classes such as phenolic acids and alcohols, secoiridoids, lignans, and flavones. The relationship between phenolic and derived compounds has been tentatively established on the basis of proposed degradation pathways. Finally, qualitative and quantitative characterizations of solid and aqueous wastes suggest that these byproducts can be considered an important natural source of phenolic compounds, mainly hydroxytyrosol, tyrosol, decarboxymethyl oleuropein aglycone, and luteolin, which, after suitable purification, could be used as food antioxidants or as ingredients in nutraceutical products due to their interesting technological and pharmaceutical properties. 相似文献
74.
Ricardo de la Fuente Jesus Almazan Esperanza Gomez-Lucia Jean Freney Guillermo Suarez 《Comparative immunology, microbiology and infectious diseases》1986,9(4):347-353
A total of 176 Gram-positive, catalase positive cocci strains, isolated from sheep were studied by different routine tests for the differentiation of staphylococci and micrococci, comparing their validity and usefulness. By glucose fermentation and growth in the anaerobic portion of thioglycolate 85 and 73.6% respectively of coagulase negative staphylococci were misclassified as Micrococcus spp. Susceptibility to lysostaphin was an adequate test for the differentiation of the strains. Atypical results in the production of acid from glycerol/erythromycin were obtained in 11.8% of the coagulase negative strains and 16.7% of micrococci. The combined use of the selective media furazolidone agar and Schleifer and Krämer medium resulted in a fast and useful separation of ovine staphylococci and micrococci. The bacteriolytic activity misclassified 32.2% of the coagulase negative strains. 相似文献
75.
Ginja MM Gonzalo-Orden JM Jesus SS Silvestre AM Llorens-Pena MP Ferreira AJ 《Veterinary journal (London, England : 1997)》2007,174(2):378-383
Simple and accurate limb and pelvic conformation evaluation using computed tomography (CT) can be useful in planning canine hip dysplasia (CHD) treatment and in helping to understand the pathogenesis of osteoarthritis and CHD. The objectives of this study were to describe a new method for femoral neck anteversion angle (FNA-angle) measurement in CT, and to compare it to the established radiographic standard biplanar method. The hips of 23 Estrela Mountain Dogs were evaluated using radiography and CT and their FNA-angles were determined by performing two CT examinations and with one radiographic measurement session. The intra-class correlation coefficient (ICC) was used to evaluate the repeatability (agreement between the two CT sessions, ICC=0.92) and reproducibility (agreement between each CT and radiographic session, ICC=0.91 in both cases) of the CT FNA-angle measurement method. This study suggests that CT FNA-angle measurement method is reliable and can be used in CT hip studies with confidence. 相似文献
76.
Grillo TP Brandão CV Mamprim MJ de Jesus CM Santos TC Minto BW 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(7):745-747
A 6-year-old male, Belgian shepherd dog was presented with lethargy, oliguria, hematuria, and reluctance to move. The dog developed hypertrophic osteopathy secondary to renal pelvis transitional cell carcinoma. A nephrectomy was performed and after a year, the dog was completely asymptomatic, and no evidence of metastatic disease was present. 相似文献
77.
78.
IMAGING DIAGNOSIS—SPONTANEOUS PNEUMOMEDIASTINUM SECONDARY TO PRIMARY PULMONARY PATHOLOGY IN A DALMATIAN DOG
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Amalia Agut Jesus Talavera Antonio Buendia Agustina Anson Giorgia Santarelli Serafin Gomez 《Veterinary radiology & ultrasound》2015,56(5):E54-E57
A 1.5‐year‐old, 23 kg intact male Dalmatian dog was evaluated for acute respiratory insufficiency without a previous history of trauma or toxic exposition. Imaging revealed pneumomediastinum, pneumothorax, diffuse unstructured interstitial pulmonary pattern, pulmonary interstitial emphysema, and pneumoretroperitoneum. Histopathological evaluation of the lungs revealed perivascular and peribronchial emphysema, mild lymphocytic interstitial pneumonia with atypical proliferation of type II pneumocytes in bronchioles and alveoli. A lung disease resembling fibrosing interstitial pneumonia in man and cats has been previously reported in Dalmatians and should be included as a differential diagnosis for Dalmatians with this combination of clinical and imaging characteristics. 相似文献
79.
André Wilson Campos Rosado Alessandra de Jesus Boari Danilo Oliveira Ramos Fábio Alex Custódio Ayane Fernanda Ferreira Quadros Izabel Cristina Alves Batista Olinto Liparini Pereira 《Forest Pathology》2023,53(2):e12808
Cycas revoluta (Cycadaceae) is commonly cultivated as an ornamental tree in several countries. In April 2015, C. revoluta leaves showing brownish spots with a yellow halo that progressed to leaflet necrosis were observed in Belém, Pará state, Brazil. This study aimed to determine the aetiology of this disease on sago palm in Brazil. Based on DNA sequence-based phylogeny, morphology, and colony characterization, the fungus was identified as Pseudopestalotiopsis elaeidis. To the best of our knowledge, this is the first report of P. elaeidis associated with leaf spots on C. revoluta worldwide. 相似文献
80.
Luciana C. Gomes Sara I. Faria Jesus Valcarcel Jos A. Vzquez Miguel A. Cerqueira Lorenzo Pastrana Ana I. Bourbon Filipe J. Mergulho 《Marine drugs》2021,19(7)
The growing requirement for sustainable processes has boosted the development of biodegradable plastic-based materials incorporating bioactive compounds obtained from waste, adding value to these products. Chitosan (Ch) is a biopolymer that can be obtained by deacetylation of chitin (found abundantly in waste from the fishery industry) and has valuable properties such as biocompatibility, biodegradability, antimicrobial activity, and easy film-forming ability. This study aimed to produce and characterize poly(lactic acid) (PLA) surfaces coated with β-chitosan and β-chitooligosaccharides from a Loligo opalescens pen with different molecular weights for application in the food industry. The PLA films with native and depolymerized Ch were functionalized through plasma oxygen treatment followed by dip-coating, and their physicochemical properties were assessed by Fourier-transform infrared spectroscopy, X-ray diffraction, water contact angle, and scanning electron microscopy. Their antimicrobial properties were assessed against Escherichia coli and Pseudomonas putida, where Ch-based surfaces reduced the number of biofilm viable, viable but nonculturable, and culturable cells by up to 73%, 74%, and 87%, respectively, compared to PLA. Biofilm growth inhibition was confirmed by confocal laser scanning microscopy. Results suggest that Ch films of higher molecular weight had higher antibiofilm activity under the food storage conditions mimicked in this work, contributing simultaneously to the reuse of marine waste. 相似文献