Relative Leaf Expansion Rate as an Indicator of Compensatory Growth of Defoliated Vines (Vitis vinifera L. cv. Prokupac)

Defoliation is a common practice in vineyards, with numerous benefits for vine microclimate conditions, andit can significantly improve the composition of grapes. In addition, early defoliation reduces the active leafarea, which affects the modifications of the source-sink balance and decreases whole-vine photosynthesis.The reaction of grapevines to early defoliation is to mitigate the effects through compensatory growth,resulting in more lateral shoots with a greater number of leaves. In this study, we evaluate the use of nondestructiveand continuous measurements of mean and lateral leaf area on the same shoots for the purposeof monitoring leaf area development and calculating relative leaf expansion rate (RLER) during activegrowth. The results show that the grapevine’s ability to recover its leaf area after defoliation dependsmainly on the time of defoliation. Vines defoliated early had time to compensate for the removed leaves byproducing a greater number of lateral shoots with more leaves, resulting in a larger total leaf area. Witha decrease in shoot growth during vegetation, the recovery ability decreases, and compensatory growthis therefore not enough to restore the reduced leaf area. Based on the value of RLER, it is shown that, ifdefoliation is performed in the period of intensive shoot growth, it retards the emergence of new shootsand leaves over several days, followed by a period of regrowth. Very slow or no growth of shoots and leavesoccurred with defoliation after the véraison stage

EFFECT OF BACTERIAL FERTILIZER ON GROWTH, YIELD AND GRAPE QUALITY OF POTTED CABERNET SAUVIGNON (VITIS VINIFERA L.)

In these studies, one commercial bacterial fertilizer - BactoFil B10 was used during the first and second growing seasons of the potted vines. The influence of the fertilization was investigated on the vine growth – total leaf area, shoot diameter, dormant pruning weight and fresh root weight. The most expressed effect of Bactofil application was in the first vegetation with increases of the total leaf area of 9%, shoot length of 6% and shoot pruning weight of 14.6%, in comparison to the control. At the end of the second vegetation, plants were removed from the pots and the fresh root weight was measured. It was found that applied treatment was not influenced on the variations of the average root weight. The first grapes were obtained in the second vegetation, and treatment with BactoFil was not influenced on the differences in the yield, grape and berry weight. Also, treatment was not influenced on the must quality which was expressed over the dry matter content and total acid content

Suitable thicknesses of base metal and interlayer, and evolution of phases for Ag/Sn/Ag transient liquid-phase joints used for power die attachment

Both real Si insulated gate bipolar transistors (IGBT) with conventional Ni\Ag metallization and a dummy Si die with thickened Ni\Ag metallization have been bonded on Ag foils electroplated with 2.7 m and 6.8 m thick Sn as an interlayer at 250ºC for 0 min, 40 min and 640 min. From microstructure characterization of the resulting joints, suitable thicknesses are suggested for the Ag base metal and the Sn interlayer for Ag/Sn/Ag transient liquid phase (TLP) joints used in power die attachment, and the diffusivities of Ag and Sn in the Ag phase are extracted. In combination with the kinetic constants of Ag3Sn growth and diffusivities of Ag and Sn in Ag reported in the literature, the extracted diffusivities of Ag and Sn in Ag phase are also used to simulate and predict the diffusion-controlled growth and evolution of phases in the Ag/Sn/Ag TLP joints during an extended bonding process and in service

Angiotensin-converting enzyme genotype and late respiratory complications of mustard gas exposure

<p>Abstract</p> <p>Background</p> <p>Exposure to mustard gas frequently results in long-term respiratory complications. However the factors which drive the development and progression of these complications remain unclear. The Renin Angiotensin System (RAS) has been implicated in lung inflammatory and fibrotic responses. Genetic variation within the gene coding for the Angiotensin Converting Enzyme (ACE), specifically the Insertion/Deletion polymorphism (I/D), is associated with variable levels of ACE and with the severity of several acute and chronic respiratory diseases. We hypothesized that the ACE genotype might influence the severity of late respiratory complications of mustard gas exposure.</p> <p>Methods</p> <p>208 Kurdish patients who had suffered high exposure to mustard gas, as defined by cutaneous lesions at initial assessment, in Sardasht, Iran on June 29 1987, underwent clinical examination, spirometric evaluation and ACE Insertion/Deletion genotyping in September 2005.</p> <p>Results</p> <p>ACE genotype was determined in 207 subjects. As a continuous variable, FEV₁% predicted tended to be higher in association with the D allele 68.03 ± 20.5%, 69.4 ± 21.4% and 74.8 ± 20.1% for II, ID and DD genotypes respectively. Median FEV₁% predicted was 73 and this was taken as a cut off between groups defined as having better or worse lung function. The ACE DD genotype was overrepresented in the better spirometry group (Chi²4.9 p = 0.03). Increasing age at the time of exposure was associated with reduced FEV₁%predicted (p = 0.001), whereas gender was not (p = 0.43).</p> <p>Conclusion</p> <p>The ACE D allele is associated with higher FEV₁% predicted when assessed 18 years after high exposure to mustard gas.</p

Analysis of human MDM4 variants in papillary thyroid carcinomas reveals new potential markers of cancer properties

A wild-type (wt) p53 gene characterizes thyroid tumors, except for the rare anaplastic histotype. Because p53 inactivation is a prerequisite for tumor development, alterations of p53 regulators represent an alternative way to impair p53 function. Indeed, murine double minute 2 (MDM2), the main p53 negative regulator, is overexpressed in many tumor histotypes including those of the thyroid. A new p53 regulator, MDM4 (a.k.a. MDMX or HDMX) an analog of MDM2, represents a new oncogene although its impact on tumor properties remains largely unexplored. We estimated levels of MDM2, MDM4, and its variants, MDM4-S (originally HDMX-S) and MDM4-211 (originally HDMX211), in a group of 57 papillary thyroid carcinomas (PTC), characterized by wt tumor protein 53, in comparison to matched contra-lateral lobe normal tissue. Further, we evaluated the association between expression levels of these genes and the histopathological features of tumors. Quantitative real-time polymerase chain reaction revealed a highly significant downregulation of MDM4 mRNA in tumor tissue compared to control tissue (P < 0.0001), a finding confirmed by western blot on a subset of 20 tissue pairs. Moreover, the tumor-to-normal ratio of MDM4 levels for each individual was significantly lower in late tumor stages, suggesting a specific downregulation of MDM4 expression with tumor progression. In comparison, MDM2 messenger RNA (mRNA) and protein levels were frequently upregulated with no correlation with MDM4 levels. Lastly, we frequently detected overexpression of MDM4-S mRNA and presence of the aberrant form, MDM4-211 in this tumor group. These findings indicate that MDM4 alterations are a frequent event in PTC. It is worthy to note that the significant downregulation of full-length MDM4 in PTC reveals a novel status of this factor in human cancer that counsels careful evaluation of its role in human tumorigenesis and of its potential as therapeutic target

Release of N2,3-ethenoguanine from chloroacetaldehyde-treated DNA by Escherichia coli 3-methyladenine DNA glycosylase II.

The human carcinogen vinyl chloride is metabolized in the liver to reactive intermediates which form N2,3-ethenoguanine in DNA. N2,3-Ethenoguanine is known to cause G----A transitions during DNA replication in Escherichia coli, and its formation may be a carcinogenic event in higher organisms. To investigate the repair of N2,3-ethenoguanine, we have prepared an N2,3-etheno[14C]guanine-containing DNA substrate by nick-translating DNA with [14C]dGTP and modifying the product with chloroacetaldehyde. E. coli 3-methyladenine DNA glycosylase II, purified from cells which carry the plasmid pYN1000, releases N2,3-ethenoguanine from chloroacetaldehyde-modified DNA in a protein- and time-dependent manner. This finding widens the known substrate specificity of glycosylase II to include a modified base which may be associated with the carcinogenic process. Similar enzymatic activity in eukaryotic cell might protect them from exposure to metabolites of vinyl chloride