931 resultados para Acid pre-treatment


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The aim of the present thesis was to better understand the physiological role of the phytohormones jasmonates (JAs) and abscisic acid (ABA) during fruit ripening in prospect of a possible field application of JAs and ABA to improve fruit yield and quality. In particular, the effects of exogenous application of these substances at different fruit developmental stages and under different experimental conditions were evaluated. Some aspects of the water relations upon ABA treatment were also analysed. Three fruit species, peach (Prunus persica L. Batsch), golden (Actinidia chinensis) and green kiwifruit (Actinidia deliciosa), and several of their cvs, were used for the trials. Different experimental models were adopted: fruits in planta, detached fruit, detached branches with fruit, girdled branches and micropropagated plants. The work was structured into four sets of experiments as follows: (i) Pre-harvest methyl jasmonate (MJ) application was performed at S3/S4 transition under field conditions in Redhaven peach; ethylene production, ripening index, fruit quality and shelf-life were assessed showing that MJ-treated fruit were firmer and thus less ripe than controls as confirmed by the Index of Absorbance Difference (IAD), but exhibited a shorter shelf-life due to an increase in ethylene production. Moreover, the time course of the expression of ethylene-, auxin- and other ripening-related genes was determined. Ripening-related ACO1 and ACS1 transcript accumulation was inhibited though transiently by MJ, and gene expression of the ethylene receptor ETR2 and of the ethylene-related transcription factor ERF2 was also altered. The time course of the expression of several auxin-related genes was strongly affected by MJ suggesting an increase in auxin biosynthesis, altered auxin conjugation and release as well as perception and transport; the need for a correct ethylene/auxin balance during ripening was confirmed. (ii) Pre- and post-harvest ABA applications were carried out under field conditions in Flaminia and O’Henry peach and Stark Red Gold nectarine fruit; ethylene production, ripening index, fruit quality and shelf-life were assessed. Results show that pre-harvest ABA applications increase fruit size and skin color intensity. Also post-harvest ABA treatments alter ripening-related parameters; in particular, while ethylene production is impaired in ABA-treated fruit soluble solids concentration (SSC) is enhanced. Following field ABA applications stem water potential was modified since ABA-treated peach trees retain more water. (iii) Pre- and post-harvest ABA and PDJ treatments were carried out in both kiwifruit species under field conditions at different fruit developmental stages and in post-harvest. Ripening index, fruit quality, plant transpiration, photosynthesis and stomatal conductance were assessed. Pre-harvest treatments enhance SSC in the two cvs and flesh color development in golden kiwifruit. Post-harvest applications of either ABA or ABA plus PDJ lead to increased SSC. In addition, ABA reduces gas exchanges in A. deliciosa. (iv) Spray, drench and dipping ABA treatments were performed in micropropagated peach plants and in peach and nectarine detached branches; plant water use and transpiration, biomass production and fruit dehydration were determined. In both plants and branches ABA significantly reduces water use and fruit dehydration. No negative effects on biomass production were detected. The present information, mainly arising from plant growth regulator application in a field environment, where plants have to cope with multiple biotic and abiotic stresses, may implement the perspectives for the use of these substances in the control of fruit ripening.

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Outdoor bronzes exposed to the environment form naturally a layer called patina, which may be able to protect the metallic substrate. However, since the last century, with the appearance of acid rains, a strong change in the nature and properties of the copper based patinas occurred [1]. Studies and general observations have established that bronze corrosion patinas created by acid rain are not only disfiguring in terms of loss of detail and homogeneity, but are also unstable [2]. The unstable patina is partially leached away by rainwater. This leaching is represented by green streaking on bronze monuments [3]. Because of the instability of the patina, conservation techniques are usually required. On a bronze object exposed to the outdoor environment, there are different actions of the rainfall and other atmospheric agents as a function of the monument shape. In fact, we recognize sheltered and unsheltered areas as regards exposure to rainwater [4]. As a consequence of these different actions, two main patina types are formed on monuments exposed to the outdoor environment. These patinas have different electrochemical, morphological and compositional characteristics [1]. In the case of sheltered areas, the patina contains mainly copper products, stratified above a layer strongly enriched in insoluble Sn oxides, located at the interface with the uncorroded metal. Moreover, different colors of the patina result from the exposure geometry. The surface color may be pale green for unsheltered areas, and green and mat black for sheltered areas [4]. Thus, in real outdoor bronze monuments, the corrosion behavior is strongly influenced by the exposure geometry. This must be taken into account when designing conservation procedures, since the patina is in most cases the support on which corrosion inhibitors are applied. Presently, for protecting outdoor bronzes against atmospheric corrosion, inhibitors and protective treatments are used. BTA and its derivatives, which are the most common inhibitors used for copper and its alloy, were found to be toxic for the environment and human health [5, 6]. Moreover, it has been demonstrated that BTA is efficient when applied on bare copper but not as efficient when applied on bare bronze [7]. Thus it was necessary to find alternative compounds. Silane-based inhibitors (already successfully tested on copper and other metallic substrates [8]), were taken into consideration as a non-toxic, environmentally friendly alternative to BTA derivatives for bronze protection. The purpose of this thesis was based on the assessment of the efficiency of a selected compound, to protect the bronze against corrosion, which is the 3-mercapto-propyl-trimethoxy-silane (PropS-SH). It was selected thanks to the collaboration with the Corrosion Studies Centre “Aldo Daccò” at the Università di Ferrara. Since previous studies [9, 10, 11] demonstrated that the addition of nanoparticles to silane-based inhibitors leads to an increase of the protective efficiency, we also wanted to evaluate the influence of the addition of CeO2, La2O3, TiO2 nanoparticles on the protective efficiency of 3-mercapto-propyl-trimethoxy-silane, applied on pre-patinated bronze surfaces. This study is the first section of the thesis. Since restorers have to work on patinated bronzes and not on bare metal (except for contemporary art), it is important to be able to recreate the patina, under laboratory conditions, either in sheltered or unsheltered conditions to test the coating and to obtain reliable results. Therefore, at the University of Bologna, different devices have been designed to simulate the real outdoor conditions and to create a patina which is representative of real application conditions of inhibitor or protective treatments. In particular, accelerated ageing devices by wet & dry (simulating the action of stagnant rain in sheltered areas [12]) and by dropping (simulating the leaching action of the rain in unsheltered areas [1]) tests were used. In the present work, we used the dropping test as a method to produce pre-patinated bronze surfaces for the application of a candidate inhibitor as well as for evaluating its protective efficiency on aged bronze (unsheltered areas). In this thesis, gilded bronzes were also studied. When they are exposed to the outside environment, a corrosion phenomenon appears which is due to the electrochemical couple gold/copper where copper is the anode. In the presence of an electrolyte, this phenomenon results in the formation of corrosion products than will cause a blistering of the gold (or a break-up and loss of the film in some cases). Moreover, because of the diffusion of the copper salts to the surface, aggregates and a greenish film will be formed on the surface of the sample [13]. By coating gilded samples with PropS-SH and PropS-SH containing nano-particles and carrying out accelerated ageing by the dropping test, a discussion is possible on the effectiveness of this coating, either with nano-particles or not, against the corrosion process. This part is the section 2 of this thesis. Finally, a discussion about laser treatment aiming at the assessment of reversibility/re-applicability of the PropS-SH coating can be found in section 3 of this thesis. Because the protective layer loses its efficiency with time, it is necessary to find a way of removing the silane layer, before applying a new one on the “bare” patina. One request is to minimize the damages that a laser treatment would create on the patina. Therefore, different laser fluences (energy/surface) were applied on the sample surface during the treatment process in order to find the best range of fluence. In particular, we made a characterization of surfaces before and after removal of PropS-SH (applied on a naturally patinated surface, and subsequently aged by natural exposure) with laser methods. The laser removal treatment was done by the CNR Institute of Applied Physics “Nello Carrara” of Sesto Fiorentino in Florence. In all the three sections of the thesis, a range of non-destructive spectroscopic methods (Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), μ-Raman spectroscopy, X-Ray diffractometry (XRD)) were used for characterizing the corroded surfaces. AAS (Atomic Absorption Spectroscopy) was used to analyze the ageing solutions from the dropping test in sections 1 and 2.

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Lipids are important for cell function and survival, but abnormal concentrations may lead to various diseases. Cholesterol homeostasis is greatly dependent on the active transport by membrane proteins, whose activities coordinate lipid status with cellular function. Intestinal Niemann-Pick C1-Like 1 protein (NPC1L1) and scavenger receptor B1 (SR-B1) participate in the uptake of extracellular cholesterol, whereas ATP binding cassette A1 (ABCA1) mediates the efflux of excessive intracellular cholesterol. Caveolin-1 binds cholesterol and fatty acids (FA) and participates in cholesterol trafficking. Sterol response element binding protein-2 (SREBP-2) is a sensor that regulates intracellular cholesterol synthesis. Given that cholesterol is a constituent of chylomicrons, whose synthesis is enhanced with an increased FA supply, we tested the hypothesis that feeding polyunsaturated FA (PUFA)-enriched diets in treatment of canine chronic enteropathies alters the mRNA expression of genes involved in cholesterol homeostasis. Using quantitative reverse transcriptase polymerase chain reaction (RT-PCR), we compared the mRNA abundance of NPC1L1, SR-B1, ABCA1, caveolin-1, and SREBP-2 in duodenal mucosal biopsies of dogs with food-responsive diarrhea (FRD; n=14) and inflammatory bowel disease (IBD; n=7) before and after treatment with cholesterol-free PUFA-enriched diets and in healthy controls (n=14). The abundance of caveolin-1, ABCA1, and SREBP-2 were altered by PUFA-enriched diets (P<0.05), whereas that of NPC1L1 and SR-B1 mRNA remained unchanged. The gene expression of caveolin-1, ABCA1, and SREBP-2 was down-regulated (P<0.05) by PUFA-enriched diets in IBD dogs only. Our results suggest that feeding PUFA-enriched diets may alter cholesterol homeostasis in duodenal mucosal cells of dogs suffering from IBD.

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Zoledronic acid 5 mg (ZOL) annually for 3 years reduces fracture risk in postmenopausal women with osteoporosis. To investigate long-term effects of ZOL on bone mineral density (BMD) and fracture risk, the Health Outcomes and Reduced Incidence with Zoledronic acid Once Yearly-Pivotal Fracture Trial (HORIZON-PFT) was extended to 6 years. In this international, multicenter, double-blind, placebo-controlled extension trial, 1233 postmenopausal women who received ZOL for 3 years in the core study were randomized to 3 additional years of ZOL (Z6, n = 616) or placebo (Z3P3, n = 617). The primary endpoint was femoral neck (FN) BMD percentage change from year 3 to 6 in the intent-to-treat (ITT) population. Secondary endpoints included other BMD sites, fractures, biochemical bone turnover markers, and safety. In years 3 to 6, FN-BMD remained constant in Z6 and dropped slightly in Z3P3 (between-treatment difference = 1.04%; 95% confidence interval 0.4 to 1.7; p = 0.0009) but remained above pretreatment levels. Other BMD sites showed similar differences. Biochemical markers remained constant in Z6 but rose slightly in Z3P3, remaining well below pretreatment levels in both. New morphometric vertebral fractures were lower in the Z6 (n = 14) versus Z3P3 (n = 30) group (odds ratio = 0.51; p = 0.035), whereas other fractures were not different. Significantly more Z6 patients had a transient increase in serum creatinine >0.5 mg/dL (0.65% versus 2.94% in Z3P3). Nonsignificant increases in Z6 of atrial fibrillation serious adverse events (2.0% versus 1.1% in Z3P3; p = 0.26) and stroke (3.1% versus 1.5% in Z3P3; p = 0.06) were seen. Postdose symptoms were similar in both groups. Reports of hypertension were significantly lower in Z6 versus Z3P3 (7.8% versus 15.1%, p < 0.001). Small differences in bone density and markers in those who continued versus those who stopped treatment suggest residual effects, and therefore, after 3 years of annual ZOL, many patients may discontinue therapy up to 3 years. However, vertebral fracture reductions suggest that those at high fracture risk, particularly vertebral fracture, may benefit by continued treatment.

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Non-alcoholic steatohepatitis (NASH) has a prevalence of 1% in Western countries. Its causes as well as its medical treatment are, to date, still debated. Recently, studies of agents suggested to have antiapoptotic, insulin-sensitizing or anti-inflammatory effects in patients with NASH have been conducted, one of which is ursodeoxycholic acid (UDCA), a tertiary bile acid. Between 1994 and 2008, four prospective randomized, double-blind, placebo-controlled studies of the treatment of NASH with UDCA were conducted. The first study, by Lindor et al., compared the impact of 13-15 mg/kg/day of UDCA to a placebo. The second study by Dufour et al. had an additional third arm that administered combination therapy with UDCA and vitamin E. The third and fourth studies by Leuschner et al. and by Ratziu et al. evaluated high doses of UDCA at 25-35 mg/kg/day, and used liver biopsies and serum liver enzyme levels to evaluate the impact of UDCA. With the exception of Ratziu et al.'s study, which was lacking a second liver biopsy, none of these studies showed any significant differences in the treatment of NASH with UDCA compared with a placebo. However, Dufour et al. did observe a significant improvement of NASH with the combination (UDCA/VitE) vs placebo therapy, whereas UDCA monotherapy was not effective in the treatment of NASH. Nevertheless, the effects of other bile acids and combination therapies need to be explored.

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Type 1 diabetes is associated with abnormalities of the growth hormone (GH)-IGF-I axis. Such abnormalities include decreased circulating levels of IGF-I. We studied the effects of IGF-I therapy (40 microg x kg(-1) x day(-1)) on protein and glucose metabolism in adults with type 1 diabetes in a randomized placebo-controlled trial. A total of 12 subjects participated, and each subject was studied at baseline and after 7 days of treatment, both in the fasting state and during a hyperinsulinemic-euglycemic amino acid clamp. Protein and glucose metabolism were assessed using infusions of [1-13C]leucine and [6-6-2H2]glucose. IGF-I administration resulted in a 51% rise in circulating IGF-I levels (P < 0.005) and a 56% decrease in the mean overnight GH concentration (P < 0.05). After IGF-I treatment, a decrease in the overnight insulin requirement (0.26+/-0.07 vs. 0.17+/-0.06 U/kg, P < 0.05) and an increase in the glucose infusion requirement were observed during the hyperinsulinemic clamp (approximately 67%, P < 0.05). Basal glucose kinetics were unchanged, but an increase in insulin-stimulated peripheral glucose disposal was observed after IGF-I therapy (37+/-6 vs. 52+/-10 micromol x kg(-1) x min(-1), P < 0.05). IGF-I administration increased the basal metabolic clearance rate for leucine (approximately 28%, P < 0.05) and resulted in a net increase in leucine balance, both in the basal state and during the hyperinsulinemic amino acid clamp (-0.17+/-0.03 vs. -0.10+/-0.02, P < 0.01, and 0.25+/-0.08 vs. 0.40+/-0.06, P < 0.05, respectively). No changes in these variables were recorded in the subjects after administration of placebo. These findings demonstrated that IGF-I replacement resulted in significant alterations in glucose and protein metabolism in the basal and insulin-stimulated states. These effects were associated with increased insulin sensitivity, and they underline the major role of IGF-I in protein and glucose metabolism in type 1 diabetes.

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Induction therapy of promyelocytic leukemia with all-trans retinoic acid is a standard therapy despite significant side-effects. The most important, the "retinoic acid syndrome", consists of a hyperinflammatory reaction with capillary leakage (edema, pleural, and pericardial effusion), infiltration of myeloid cells into internal organs and systemic signs of inflammation. We describe here two cases of another hyperinflammatory reaction during all-trans retinoic acid therapy, the Sweet's syndrome, consisting of infiltrates of the skin and internal organs by neutrophilic granulocytes. Fever, painful erythematous cutaneous plaques, prominent musculoskeletal involvement (myositis, fasciitis), a sterile pulmonary infiltration and intercurrent proteinuria characterized the clinical course of all-trans retinoic acid-associated Sweet's syndrome. Treatment with glucocorticoids led to resolution of the syndrome within 48 h. Three other cases of all-trans retinoic acid-associated Sweet's syndrome without involvement of internal organs, prominent on our cases, were published previously. Recognition of ATRA-associated Sweet's syndrome is of practical importance.

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While bisphosphonates reduce fracture risk over 3 to 5 years, the optimal duration of treatment is uncertain. In a randomized extension study (E1) of the Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly - Pivotal Fracture Trial (HORIZON-PFT), zoledronic acid (ZOL) 5 mg annually for 6 years showed maintenance of bone mineral density (BMD), decrease in morphometric vertebral fractures, and a modest reduction in bone turnover markers (BTMs) compared with discontinuation after 3 years. To investigate the longer-term efficacy and safety of ZOL, a second extension (E2) was conducted to 9 years in which women on ZOL for 6 years in E1 were randomized to either ZOL (Z9) or placebo (Z6P3) for 3 additional years. In this multicenter, randomized, double-blind study, 190 women were randomized to Z9 (n=95) and Z6P3 (n=95). The primary endpoint was change in total hip BMD at year 9 vs. year 6 in Z9 compared with Z6P3. Other secondary endpoints included fractures, BTMs, and safety. From year 6 to 9, the mean change in total hip BMD was -0.54% in Z9 vs. -1.31% in Z6P3 (difference 0.78%; 95% confidence interval [CI]: -0.37%, 1.93%; p=0.183). BTMs showed small, non-significant increases in those who discontinued after 6 years compared with those who continued for 9 years. The number of fractures was low and did not significantly differ by treatment. While generally safe, there was a small increase in cardiac arrhythmias (combined serious and non-serious) in the Z9 group but no significant imbalance in other safety parameters. The results suggest almost all patients who have received six annual ZOL infusions can stop medication for up to 3 years with apparent maintenance of benefits. This article is protected by copyright. All rights reserved.

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Patients living with a spinal cord injury (SCI) often develop chronic neuropathic pain (CNP). Unfortunately, the clinically approved, current standard of treatment, gabapentin, only provides temporary pain relief. This treatment can cause numerous adverse side effects that negatively affect the daily lives of SCI patients. There is a great need for alternative, effective treatments for SCI-dependent CNP. Minocycline, an FDA-approved antibiotic, has been widely prescribed for the treatment of acne for several decades. However, recent studies demonstrate that minocycline has neuroprotective properties in several pre-clinical rodent models of CNS trauma and disease. Pre-clinical studies also show that short-term minocycline treatment can prevent the onset of CNP when delivered during the acute stage of SCI and can also transiently attenuate established CNP when delivered briefly during the chronic stage of SCI. However, the potential to abolish or attenuate CNP via long-term administration of minocycline after SCI is unknown. The purpose of this study was to investigate the potential efficacy and safety of long-term administration of minocycline to abolish or attenuate CNP following SCI. A severe spinal contusion injury was administered on adult, male, Sprague-Dawley rats. At day 29 post-injury, I initiated a three-week treatment regimen of daily administration with minocycline (50 mg/kg), gabapentin (50 mg/kg) or saline. The minocycline treatment group demonstrated a significant reduction in below-level mechanical allodynia and above- level hyperalgesia while on their treatment regimen. After a ten-day washout period of minocycline, the animals continued to demonstrate a significant reduction in below-level mechanical allodynia and above-level hyperalgesia. However, minocycline-treated animals exhibited abnormal weight gain and hepatotoxicity compared to gapabentin-treated or vehicle-treated subjects.The results support previous findings that minocycline can attenuate CNP after SCI and suggested that minocycline can also attenuate CNP via long-term delivery of minocycline after SCI (36). The data also suggested that minocycline had a lasting effect at reducing pain symptoms. However, the adverse side effects of long-term use of minocycline should not be ignored in the rodent model. Gabapentin treatment caused a significant decrease in below-level mechanical allodynia and below-level hyperalgesia during the treatment regimen. Because gabapentin treatment has an analgesic effect at the concentration I administered, the results were expected. However, I also found that gabapentin-treated animals demonstrated a sustained reduction in pain ten days after treatment withdrawal. This result was unexpected because gabapentin has a short half-life of 1.7 hours in rodents and previous studies have demonstrated that pre-drug pain levels return shortly after withdrawal of treatment. Additionally, the gabapentin-treated animals demonstrated a significant and sustained increase in rearing events compared with all other treatment groups which suggested that gabapentin treatment was not only capable of reducing pain long-term but may also significantly improve trunk stability or improve motor function recovery.

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Anthropogenic climate change confronts marine organisms with rapid trends of concomitant warming and CO2 induced ocean acidification. The survival and distribution of species partly depend on their ability to exploit their physiological plasticity during acclimatization. Therefore, in laboratory studies the effects of simulated future ocean acidification on thermal tolerance, energy metabolism and acid-base regulation capacity of the North Sea population of the blue mussel Mytilus edulis were examined. Following one month of pre-acclimation to 10 °C and control CO2 levels, mussels were exposed for two weeks to control and projected oceanic CO2 levels (390, 750 and 1120 µatm) before being subjected to a stepwise warming protocol between 10 °C and 31 °C (+ 3 °C each night). Oxygen consumption and heart rates, anaerobic metabolite levels and haemolymph acid-base status were determined at each temperature. CO2 exposure left oxygen consumption rate unchanged at acclimation temperature but caused a somewhat stronger increase during acute warming and thus mildly higher Q10-values than seen in controls. Interestingly, the thermally induced limitation of oxygen consumption rate set in earlier in normocapnic than in hypercapnic (1120 µatm CO2) mussels (25.2 °C vs. 28.8 °C), likely due to an onset of metabolic depression in the control group following warming. However, the temperature induced increase in heart rate became limited above 25 °C in both groups indicating an unchanged pejus temperature regardless of CO2 treatment. An upper critical temperature was reached above 28 °C in both treatments indicated by the accumulation of anaerobic metabolites in the mantle tissue, paralleled by a strong increase in haemolymph PCO2 at 31 °C. Ocean acidification caused a decrease in haemolymph pH. The extracellular acidosis remained largely uncompensated despite some bicarbonate accumulation. In all treatments animals developed a progressive warming-induced extracellular acidosis. A stronger pH drop at around 25 °C was followed by stagnating heart rates. However, normocapnic mussels enhanced bicarbonate accumulation at the critical limit, a strategy no longer available to hypercapnic mussels. In conclusion, CO2 has small effects on the response patterns of mussels to warming, leaving thermal thresholds largely unaffected. High resilience of adult North Sea mussels to future ocean acidification indicates that sensitivity to thermal stress is more relevant in shaping the response to future climate change.

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Anthropogenic CO2 emission will lead to an increase in seawater pCO2 of up to 80-100 Pa (800-1000 µatm) within this century and to an acidification of the oceans. Green sea urchins (Strongylocentrotus droebachiensis) occurring in Kattegat experience seasonal hypercapnic and hypoxic conditions already today. Thus, anthropogenic CO2 emissions will add up to existing values and will lead to even higher pCO2 values >200 Pa (>2000 µatm). To estimate the green sea urchins' potential to acclimate to acidified seawater, we calculated an energy budget and determined the extracellular acid base status of adult S. droebachiensis exposed to moderately (102 to 145 Pa, 1007 to 1431 µatm) and highly (284 to 385 Pa, 2800 to 3800 µatm) elevated seawater pCO2 for 10 and 45 days. A 45 - day exposure to elevated pCO2 resulted in a shift in energy budgets, leading to reduced somatic and reproductive growth. Metabolic rates were not significantly affected, but ammonium excretion increased in response to elevated pCO2. This led to decreased O:N ratios. These findings suggest that protein metabolism is possibly enhanced under elevated pCO2 in order to support ion homeostasis by increasing net acid extrusion. The perivisceral coelomic fluid acid-base status revealed that S. droebachiensis is able to fully (intermediate pCO2) or partially (high pCO2) compensate extracellular pH (pHe) changes by accumulation of bicarbonate (maximum increases 2.5 mM), albeit at a slower rate than typically observed in other taxa (10 day duration for full pHe compensation). At intermediate pCO2, sea urchins were able to maintain fully compensated pHe for 45 days. Sea urchins from the higher pCO2 treatment could be divided into two groups following medium-term acclimation: one group of experimental animals (29%) contained remnants of food in their digestive system and maintained partially compensated pHe (+2.3 mM HCO3), while the other group (71%) exhibited an empty digestive system and a severe metabolic acidosis (-0.5 pH units, -2.4 mM HCO3). There was no difference in mortality between the three pCO2 treatments. The results of this study suggest that S. droebachiensis occurring in the Kattegat might be pre-adapted to hypercapnia due to natural variability in pCO2 in its habitat. We show for the first time that some echinoderm species can actively compensate extracellular pH. Seawater pCO2 values of >200 Pa, which will occur in the Kattegat within this century during seasonal hypoxic events, can possibly only be endured for a short time period of a few weeks. Increases in anthropogenic CO2 emissions and leakages from potential sub-seabed CO2 storage (CCS) sites thus impose a threat to the ecologically and economically important species S. droebachiensis.

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La presente Tesis Doctoral se realizó con el fin de estimar conjuntamente la respuesta agronómica y fisiológica de la vid (Vitis vinifera L.), así como los efectos sobre la evolución de la maduración, composición y la calidad de la uva y del vino, bajo la aplicación de diferentes déficit hídricos en pre-envero y post-envero, dentro de un marco de referencia de cambio climático. La variación climática que prevén los estudios sobre el cambio climático, resulta un factor decisivo en la eficiencia del uso del agua en la vid. En zonas cálidas, las estrategias de cultivo del viñedo frente al cambio climático deben de ir dirigidas a atenuar sus efectos sobre el crecimiento y el desarrollo de la vid, haciéndose imprescindible el estudio pormenorizado del déficit hídrico como factor decisivo en la obtención de las uvas adecuadas, ya que son la clave indispensable para el éxito en la elaboración del vino, y de forma muy especial en los vinos enfocados a un sector de alta calidad. El ensayo se llevó a cabo en un viñedo comercial de Bodegas Licinia, en la Comunidad de Madrid, durante los años 2010 y 2011. La variedad estudiada fue Cabernet sauvignon / 41 B, plantada a un marco de plantación de 3 m x 1 m, con un guiado vertical de la vegetación. El dispositivo experimental fue totalmente al azar, y se establecieron 4 tratamientos experimentales con 4 grados de disponibilidad hídrica, déficit moderado continuo (T0,45-0,6), déficit severo continuo (T0-0,3), déficit severo después de envero (T0,45-0,3) y déficit severo antes de envero (T0-0,6). En cada tratamiento se distribuyeron 3 repeticiones. El año 2010 fue el más lluvioso de los años de ensayo, con 478 mm de precipitaciones anuales, lo que supuso 146 mm más que en el año 2011. Su distribución a lo largo del ciclo fue más homogénea en el año 2010, mientras que en 2011 las precipitaciones contabilizadas en el período de maduración de la uva fueron nulas. La temperatura media subió 0,9ºC en 2011, respecto a 2010 y en cuanto a la integral térmica eficaz, en 2011 se acumularon, desde el 1 de abril hasta el final de ciclo, 217 grados•día más que en 2010. El déficit hídrico en pre-envero, modificó notablemente el crecimiento vegetativo y la producción de cosecha de la parcela de ensayo, no así la fertilidad de las yemas. El tratamiento con mayor disponibilidad hídrica (T0,45-0,6) obtuvo el mayor peso de baya, y los tratamientos con menor déficit hídrico en pre-envero (T0,45-0,6 y T0,45-0,3) registraron los mayores rendimientos de cosecha, mientras que las menores tasas de cuajado correspondieron al tratamiento con un déficit severo continuo (T0-0,3). La parcela de ensayo se caracterizó por un exceso de vigor y un alto crecimiento vegetativo. El pH del mosto se vio afectado por el déficit hídrico, disminuyendo su valor en el tratamiento de déficit hídrico severo antes de envero (T0-0,6). Organolépticamente, no se percibieron diferencias significativas en los vinos elaborados en función del déficit hídrico, y respecto a su composición físico-química, solo existieron diferencias en la concentración de ácido L-Málico, con mayores concentraciones en los tratamientos sin déficit hídrico en pre-envero, T0,45-0,6 y T0,45-0,3. El déficit hídrico modificó notablemente el color del vino, aumentando los valores de las coordenadas CIELAB a* y b*, la luminosidad (L*), croma (C*) y tonalidad (H*), para los tratamientos con un déficit severo en pre-envero (T0-0,3 y T0-0,6) y disminuyendo estas en el tratamiento con mayor disponibilidad hídrica (T0,45-0,6). Del mismo modo, mediante el análisis de color por métodos tradicionales, IPT e IC de los vinos, aumentó en los tratamientos con mayor déficit hídrico en pre-envero (T0-0,3 y T0-0,6), respecto a los tratamientos de mayor disponibilidad (T0,45-0,6 y T0,45-0,3). La concentración de taninos de la baya en vendimia, no se vio afectada por el déficit hídrico, aunque sí estuvo relacionada positivamente con el tamaño de las bayas. Organolépticamente, los hollejos del año 2011 resultaron con menor frescura, acidez, afrutado, sensación herbácea e intensidad tánica, aunque con mayor astringencia respecto a 2010. Las pepitas fueron más astringentes y aromáticas pero menos crujientes, sin llegar a los niveles de madurez del año 2010. El catador relacionó los taninos con la calidad del vino, asociándolos con un mayor cuerpo, acidez, intensidad, equilibrio gustativo, amargor y menor astringencia en la fase gustativa. La concentración de taninos en los vinos se vio favorecida con el déficit hídrico en pre-envero y post-envero. Los tratamientos con mayor déficit hídrico en pre-envero, T0-0,6 y T0-0,3, obtuvieron las menores concentraciones de potasio en mostos y vinos. Las relaciones entre la concentración de potasio, ácido L-Málico y el porcentaje de color rojo puro (dA(%)) resultaron altamente significativas, de modo que las mayores tasas de potasio en el vino se asociaron a los valores más bajos de color rojo y a los mayores de ácido L-Málico. ABSTRACT The present Doctoral Thesis has been done in order to estimate the grapevine (Vitis vinifera L.) agronomic and physiologic performance or response as well as the impact in the grape and wine maturity, composition and quality evolution, with different water deficits. The variation in climate that the global warming studies for seen is a key factor for the grapevine water use efficiency. In warm areas the farming vineyards strategy to face the climatic change, should be focused on diminish the effects on the grapevine growth and development, so that the water deficit detailed analysis becomes decisive to obtain the appropriate grapes, that are the main subject for a successful wine production and especially for top quality wines. The trial was carried out in a commercial vineyard in Chinchón (Madrid), Licinia winery, during the 2010 and 2011 seasons. The grape variety studied was Cabernet Sauvignon grafted onto 41B with a vine spacing 3m x 1m trained as VSP. Experimental design consisted on 4 irrigation treatments with 3 replications totally randomized. Irrigation treatments were: moderate regulated deficit (T0,45-0,6), severe continuous deficit (T0-0,3), severe post-veraison deficit (T0,45-0,3) and severe pre veraison deficit (T0-0,6). The 2010 was rainier year than the 2011; Total annual rain in 2010 was 478 mm, which resulted in 146 mm more than in 2011. The distribution along the vine cycle was more homogeneous in the 2010, whereas precipitations in 2011 along the grape maturity period were nonexistent. The average temperature in 2011 was 0,9ºC higher than that of the 2010 and regarding to the thermal integral, in the 2011 from 1st April to the end of the growing cycle, was 217 degrees•day higher than that in 2010. Water deficit significantly modified the vegetative growth and yield but, it did not modified bud fertility. The treatment with the highest water availability (T0,45-0,6) got the highest berry size, the lowest berry set rates were found in the severe continuous deficit treatment (T0-0,3). The plot studied in this trial was characterized by both excessive vigour and vegetative growth. Water deficit modified the pH must by, reducing it in the severe water deficit during pre-veraison (T0-0,6). There were not differences in wine tasting between the water deficits treatments. Regarding to the physical-chemical composition, it only existed differences in the L-malic acid concentration, resulting higher concentrations in the water deficit pre-veraison treatments: T0,45-0,6 y T0,45-0,3. Water deficit significantly modified wine colour by, increasing the CIELAB coordinates a* and b*, the brightness (L*), croma (C*) and tonality (H*), in the lower water availability pre-veraison treatments (T0-0,3 y T0-0,6), and reducing them in the in the moderate continuous water deficit ones (T0,45-0,6). By means of traditional wine colour parameters analyses, red colour percentage, TPI, they became higher in the lower water availability pre-veraison treatments (T0-0,3 y T0-0,6), than in those with higher availability (T0,45-0,6 y T0,45-0,3). At harvest, berry tannins concentrations was not affected by the water deficit although it did in a positive way, in the berry size. Berry tasting in 2011, resulted in a lower freshness, acidity, fruity, herbaceous flavour and tannic intensity, but with higher astringency respect to the 2010 season. Seeds, in 2011, were more astringent and aromatic as in the 2010, but less crunchy, without getting to the point of maturity. The taster linked the tannins to wine quality, associating them with a higher bodiest wine, acidity, intensity, taste balance, bitterness and with a lower astringency in the tasting stage. Treatments with a higher water deficit up to veraison T0-0,6 y T0-0,3 got less musts and wines potassium concentration. The relation between L-malic acid and the full red color percentage (dA(%)), were highly related, resulting the higher potassium content the lower wine quality.