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61.
When attempting to estimate the impacts of future climate change it is important to reflect on information gathered during the past. Understanding historical trends may also aid in the assessment of likely future agricultural and horticultural changes. The timing of agricultural activities, such as grape harvest dates, is known to be influenced by climate and weather. However, fewer studies have been carried out on grapevine yield and quality. In this paper an analysis is undertaken of long-term data from the period 1805–2010 on grapevine yield (hl/ha) and must sugar content (°Oe) and their relation to temperature. Monthly mean temperatures were obtained for the same time period. Multiple regression was used to relate the viticulture variables to temperature, and long-term trends were calculated. Overall, the observed trends over time are compatible with results from other long term studies. The findings confirm a relationship between yield, must sugar content and temperature data; increased temperatures were associated with higher yields and higher must sugar content. However, the potential increase in yield is currently limited by legislation, while must sugar content is likely to further increase with rising temperatures. 相似文献
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63.
Purification and characterization of the 3-hydroxybenzoate-6-hydroxylase from Klebsiella pneumoniae 总被引:1,自引:0,他引:1
Mónica Suárez Estrella Ferrer Amando Garrido-Pertierra Margarita Martín 《FEMS microbiology letters》1995,126(3):283-290
Abstract We isolated 3-hydroxybenzoate-6-hydroxylase (E.C. 1.14.13.), an inducible enzyme that catalyzed the para -hydroxylation of 3-hydroxybenzoate (3-HBA) to 2,5-dihydroxybenzoate, from Klebsiella pneumoniae . Although the enzyme was found to be mainly induced by its substrate, a coordinated induction of 3-hydroxybenzoate hydroxylase and gentisate dioxygenase was also observed in the presence of the product of the reaction. The purified enzyme was a monomer with a molecular mass of 42 000. It contained FAD as a prosthetic group, utilized NADH or NADPH with similar efficiencies and its activity was inhibited by Cu2+ , Fe2+ and Hg2+ . Other properties, such as induction mechanism and kinetic parameters were also studied. Moreover, for the first time the amino acid composition of a 3-hydroxybenzoate-6-hydroxylase was determined. 相似文献
64.
Gladys Vidal Estrella Aspé M. Cristina Marti Marlene Roeckel 《Biotechnology letters》1997,19(2):117-122
Fishmeal industries processes produce effluents with high load organic matter. These effluents, after recycling and physical-chemical pretreatment, have a high organic content (5-6 g COD/l), proteins (3-5 g/l), salinity close to sea water, sodium chloride (30 g/l) and sulphate (1-3.3 g/l). An anaerobic filter was used for the treatment of this wastewater, with marine sediment as anaerobic inoculum. Anaerobic filter removed up to 70% of the influent COD concentrations at organic loading rates (OLR) of 9.5 and 14.3 (g/l d) and sulphate up to 80% at OLR of 7.1 and 14.3 (g/l d) whereas the pH ranged between 7.0 and 7.5. These results show that anaerobic filter systems are applicable to recycled wastewaters from fishmeal. 相似文献
65.
Luana Alves Rodrigues Eduardo Augusto Ruas Paulo Maurício Ruas Maikel Reck Fernando Gianetti Fiorin María Ángeles Ortiz Estrella Urtubey Nelson Ivo Matzenbacher Claudete Fátima Ruas 《Plant Species Biology》2016,31(1):55-64
The genus Hypochaeris has a recent evolutionary history caused by long‐distance dispersal in conjunction with adaptive radiation in the South American continent. Hypochaeris lutea is a perennial herb that grows mostly at altitudes of around 1000 m in cold swamps of the southern regions of Brazil. We investigated the amplified fragment length polymorphism (AFLP) in 270 individuals representing 11 Brazilian populations of H. lutea to elucidate the population genetic structure of this species. The frequencies of polymorphic loci and gene diversity ranged from 83.42% to 91.66% and from 0.26 to 0.34, respectively. Analysis of molecular variance revealed that most of the genetic variability was found within (76.67%) rather than among (23.3%) populations, agreeing with the pattern of genetic distribution within and among populations observed in other allogamous species of Hypochaeris. A Mantel test showed no correlation between genetic and geographic distances when all populations were considered. Simulations performed using a Bayesian approach consistently identified two clusters with different admixture proportions of individuals, as also revealed by a UPGMA dendrogram of populations. The pattern of genetic structure observed in H. lutea is consistent with a process of successive colonization events by long‐distance dispersal resembling the rapid and recent radiation that has been proposed to explain the origin of the South American species of Hypochaeris. 相似文献
66.
Urease activity in Evernia prunastri (L.) Ach. thallus is induced by incubation of lichen samples on 20 m M N,N-dimethylformamide and 20 m M N-formylurea or 40 m M thiourea although, in these two last cases, activity subsequently decreases again. The induction of enzyme activity is repressed by including 40 μ M cycloheximide in the medium. Filtration through Sepharose 6B of cell-free extracts from thalli incubated on 20 m M N,N-dimethylformamide shows a main peak of urease activity which has a molecular weight of about 560000 dalton. However, those extracts from thalli floated on 20 m M N-formylurea and 40 m M thiourea show several peaks of similar enzyme activity, which have molecular weights of about 1 100000, 670000, 260000 and 140000 dalton and 1 100000, 670000 and 140000 dalton respectively.
A time-course of urease activity could be related to the accumulation of lichen phenols in the thallus for samples incubated on N,N-dimethylformamide and thiourea. 相似文献
A time-course of urease activity could be related to the accumulation of lichen phenols in the thallus for samples incubated on N,N-dimethylformamide and thiourea. 相似文献
67.
Ribonucleotide reductase activity is coupled to DNA synthesis via proliferating cell nuclear antigen
Salguero I Guarino E Shepherd ME Deegan TD Havens CG MacNeill SA Walter JC Kearsey SE 《Current biology : CB》2012,22(8):720-726
Synthesis of deoxynucleoside triphosphates (dNTPs) is required for both DNA replication and DNA repair and is catalyzed by ribonucleotide reductases (RNR), which convert ribonucleotides to their deoxy forms [1, 2]. Maintaining the correct levels of dNTPs for DNA synthesis is important for minimizing the mutation rate [3-7], and this is achieved by tight regulation of RNR [2, 8, 9]. In fission yeast, RNR is regulated in part by a small protein inhibitor, Spd1, which is degraded in S phase and after DNA damage to allow upregulation of dNTP supply [10-12]. Spd1 degradation is mediated by the activity of the CRL4(Cdt2) ubiquitin ligase complex [5, 13, 14]. This has been reported to be dependent on modulation of Cdt2 levels, which are cell cycle regulated, peaking in S phase, and which also increase after DNA damage in a checkpoint-dependent manner [7, 13]. We show here that Cdt2 level fluctuations are not sufficient to regulate Spd1 proteolysis and that the key step in this event is the interaction of Spd1 with the polymerase processivity factor proliferating cell nuclear antigen (PCNA), complexed onto DNA. This mechanism thus provides a direct link between DNA synthesis and RNR regulation. 相似文献
68.
69.
A mathematical model was developed for a compact anoxic-anaerobic-aerobic filter reactor with liquid recirculation for the treatment of fishing effluents. The model includes denitrification, anaerobic digestion, aerobic carbon oxidation and nitrification steps, as well as an evaluation of the liquid gas mass transfer and pH. The model was calibrated using one experimental condition at a recycling ratio (R)=10, and was validated with R equal to 2 and 0, with an organic concentration of 554±24 mg TOCL(-1), salinity of 24 g L(-1) and hydraulic retention time (HRT) of 2 d. Carbon total removal is higher than 98%, while maximum nitrogen removal is 62% using total nitrification in the aerobic zone, due to a higher quantity of NO(x) produced which were recirculated to the anoxic zone. In the aerobic zone, simultaneous nitrification and denitrification processes occur, because the diffusion limitations cause a low oxygen penetration in the biofilm. In the anoxic-anaerobic zone, denitrification or methanogenesis inhibition by DO (caused by the recycled oxygen) is not observed. 相似文献
70.
Esteve C Nueda A Díaz JL Beleta J Cárdenas A Lozoya E Cadavid MI Loza MI Ryder H Vidal B 《Bioorganic & medicinal chemistry letters》2006,16(14):3642-3645
A new series of 4-(1,3-dialkyl-2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo[3,2-d]pyrimidin-6-yl)benzenesulfonamides has been identified as potent A2B adenosine receptor antagonists. The products have been evaluated for their binding affinities for the human A2B, A1 and A3 adenosine receptors. 6-(4-{[4-(4-Bromobenzyl)piperazin-1-yl]sulfonyl}phenyl)-1,3-dimethyl-1H-pyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (16) showed a high affinity for the A2B adenosine receptor (IC50=1 nM) and selectivity (A1: 183x; A3: 12660x). Synthesis and SAR of this novel class of compounds showing improved absorption properties is presented herein. 相似文献