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51.
Ciro Abbud Righi Otávio Camargo Campoe Marcos Silveira Bernardes Aureny Maria Pereira Lunz Sônia Maria Stefano Piedade Carlos Rodrigues Pereira 《Agroforestry Systems》2013,87(6):1351-1362
The coffee leaf-miner (CLM) (Leucoptera coffeella Guérin-Mèneville; Lepidoptera: Lyonetiidae), the main pest of coffee plants, occurs widely throughout the Neotropics where it has a significant, negative economic and quantitative impact on coffee production. This study was conducted in a rubber tree/coffee plant interface that was influenced by the trees to a varying degrees depending on the location of the coffee plants, i.e. from beneath the rubber trees, extending through a range of distances from the edge of the tree plantation to end in a coffee monocrop field. The most severe damage inflicted on coffee plants by the CLM (number of mined leaves) from April, which marks the start of the water deficit period, until September 2003 was in the zone close to the rubber trees, whereas the damage inflicted on plants in the monocropped field was comparable to that on coffee plants grown directly beneath the rubber trees, which received about 25–40 % of the available irradiance (Ir—available irradiation at a certain position divided by the irradiation received in full sunlight, i.e. in the monocrop). From May until July damage caused by the CLM nearly doubled in each month. In midwinter (July), the damage decreased perceptibly from the tree edge toward the open field. From September onward, with the rising air temperatures CLM damage in the coffee monocrop started to increase. Based on these results, we conclude that coffee plants grown in the full sun incurred the most damage only at the end of winter, with warming air temperatures. Coffee plants grown in shadier locations (25–40 % Ir) were less damaged by the CLM, although a higher proportion of their leaves were mined. The rubber trees probably acted as a shelter during the cold autumn and winter seasons, leading to greater CLM damage over a distance outside the rubber tree plantation that was about equal to the height of the trees. Future studies should attempt to relate leaf hydric potential to pest attack in field conditions. More rigorous measurements of shade conditions could improve our understanding of the relationship of this factor to CLM attack. 相似文献
52.
- 1. Knowledge about processes and dynamics underlying organic matter accumulation in transitional waters is crucial for the protection of these ecologically important coastal habitats. This study investigated the relationship between large particle accumulation and decomposition in a coastal lake included in a Site of Community Interest (SCI) using sediment trap and litterbag techniques.
- 2. Two sets of sediment traps were deployed at five sites along the longitudinal axis of the lake. One set was emptied once a month for 12 months, and the other twice a year. The contents of the monthly and the 6‐monthly traps and the superficial sediments were then compared to estimate the organic matter accumulation and loss. To determine the mass loss rate of the three major allochthonous sources of detritus (the reed Phragmites australis, the cordgrass Spartina juncea, and the seagrass Posidonia oceanica), litterbags were placed near the sediment traps at three out of the five sites at the beginning of each 6‐month period and retrieved monthly.
- 3. The amount of annual particulate organic matter (POM) deposition in the traps was 1320.2±58.5 g m?2 y?1 and consisted of 25% large particles (CPOM). Allochthonous litter comprised an important fraction of CPOM, and its breakdown rate changed with the plant species, site and season. Loss rate of CPOM accumulated at the lake bottom was significantly related with the mass loss rate of reed and cordgrass litter, but not with that of seagrass.
- 4. Due to slow litter breakdown and tidal landward advection, the lake acted as a sediment trap for allochthonous matter, especially from Posidonia. The important role of marine‐derived litter in organic matter sedimentation suggests addressing conservation strategies of the lake functioning towards the selective control of allochthonous CPOM inputs, in particular at the mouth where the incoming tide brings suspended material and salinity decelerates matter flow to the sea and decomposition. This study supports the hypothesis that sedimentation and decomposition dynamics are important factors for coastal lake evolution, and shows litterbag and sediment trap techniques as simple useful investigation tools in management strategies aiming at conserving transitional waters.
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An 18-month-old cross-breed dog developed multiple skin nodules, which over 8 months had increased in size and number. Biopsy samples were submitted for histopathological examination and revealed multiple benign pilomatrixomas. The dog was treated with 1 mg kg(-1) isotretinoin daily, which led to a stabilization of the size and number of the lesions. Attempts to lower the dosage to an every other day regimen led to an increase in the nodules' size and number. Monthly complete blood count and chemistry tests and Schirmer tear tests were performed to monitor any adverse effects of the retinoid treatment. No adverse effects were noted. To the authors' knowledge, this is the first report of multiple pilomatrixomas arising in a young dog and successfully controlled with oral retinoids. 相似文献
55.
Stover J Bertozzi S Gutierrez JP Walker N Stanecki KA Greener R Gouws E Hankins C Garnett GP Salomon JA Boerma JT De Lay P Ghys PD 《Science (New York, N.Y.)》2006,311(5766):1474-1476
A strong, global commitment to expanded prevention programs targeted at sexual transmission and transmission among injecting drug users, started now, could avert 28 million new HIV infections between 2005 and 2015. This figure is more than half of the new infections that might otherwise occur during that period in 125 low- and middle-income countries. Although preventing these new infections would require investing about U.S.$122 billion over this period, it would reduce future needs for treatment and care. Our analysis suggests that it will cost about U.S.$3900 to prevent each new infection, but that this will produce a savings of U.S.$4700 in forgone treatment and care costs. Thus, greater spending on prevention now would not only prevent more than half the new infections that would occur from 2005 to 2015 but would actually produce a net financial saving as future costs for treatment and care are averted. 相似文献
56.
Di Palma S Brunetti B Doherr MG Forster U Hilbe M Zurbriggen A Vandevelde M Oevermann A 《Comparative immunology, microbiology and infectious diseases》2012,35(5):429-441
This study examined the spatiotemporal immune response in listeric rhombencephalitis of ruminants in situ. Our data support the view that astrocytes facilitate the containment of infectious lesions. Results on the natural disease recapitulate observations in experimental rodent models and suggest that the mounted adaptive lymphocytic response of ruminants is effective in eliminating Listeria monocytogenes (LM). However, our data indicate earlier participation of the adaptive immune response, a stronger B lymphocyte contribution and a more protracted macrophage infiltration in the natural disease than it has been deduced from experimental models. Therefore, such models should be complemented by studies in natural host systems. Various macrophage and microglia subsets are involved in listeric rhombencephalitis and their differential contribution may account for species differences in clinical course and outcome of infection as might species differences in the B-cell response. Future functional ex vivo and in vitro studies are necessary to further investigate the findings obtained in the present study. 相似文献
57.
58.
Antonella Leone Raffaella Marina Lecci Miriana Durante Stefano Piraino 《Marine drugs》2013,11(5):1728-1762
On a global scale, jellyfish populations in coastal marine ecosystems exhibit increasing trends of abundance. High-density outbreaks may directly or indirectly affect human economical and recreational activities, as well as public health. As the interest in biology of marine jellyfish grows, a number of jellyfish metabolites with healthy potential, such as anticancer or antioxidant activities, is increasingly reported. In this study, the Mediterranean “fried egg jellyfish” Cotylorhiza tuberculata (Macri, 1778) has been targeted in the search forputative valuable bioactive compounds. A medusa extract was obtained, fractionated, characterized by HPLC, GC-MS and SDS-PAGE and assayed for its biological activity on breast cancer cells (MCF-7) and human epidermal keratinocytes (HEKa). The composition of the jellyfish extract included photosynthetic pigments, valuable ω-3 and ω-6 fatty acids, and polypeptides derived either from jellyfish tissues and their algal symbionts. Extract fractions showed antioxidant activity and the ability to affect cell viability and intercellular communication mediated by gap junctions (GJIC) differentially in MCF-7and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanism for the anticancer bioactivity through the modulation of GJIC has been hypothesized and its nutraceutical and pharmaceutical potential was discussed. 相似文献
59.
Schievano E Pasini G Cozzi G Mammi S 《Journal of agricultural and food chemistry》2008,56(16):7208-7214
In the present work, a rapid and simple NMR method to discriminate Asiago d'Allevo cheese samples from different production chains is described. A fast and reproducible extraction of the organic fraction was employed. By applying chemometric analysis to NMR data, it is possible to differentiate PDO Asiago cheese produced in alpine farms from that produced in lowland and mountain industrialized factories. PCA of both (1)H and (13)C NMR spectra showed a good separation of alpine farm products from the other ones, whereas the lowland and mountain industrialized cheeses are undistinguishable. The samples were differentiated on the basis of a higher content of unsaturated fatty acids, principally oleic, linoleic, linolenic, and conjugated linoleic acids for the alpine farm cheeses and a higher content of saturated fatty acids for the industrialized products. Conjugated linoleic acid and 1-pentene are also discriminating components. 相似文献
60.
Nicola Tomasi Laure Weisskopf Giancarlo Renella Loretta Landi Roberto Pinton Zeno Varanini Paolo Nannipieri Josè Torrent Enrico Martinoia Stefano Cesco 《Soil biology & biochemistry》2008,40(7):1971-1974
The impact of flavonoids released by phosphorus-deficient white lupin roots on inorganic P and soil microorganisms is largely unknown. We report that flavonoids isolated from white lupin roots mobilized inorganic phosphorus and decreased soil microbial respiration, citrate mineralization, and soil phosphohydrolase activities, but did not reduce the soil ATP content. The results suggest that white lupin's release of flavonoids into the rhizosphere plays a significant role in its efficient P-acquisition strategy by solubilizing Fe-bound P and by limiting the microbial mineralization of citrate. 相似文献