Spermatozoal sensitive biomarkers to defective protaminosis and fragmented DNA

Human sperm DNA damage may have adverse effects on reproductive outcome. Infertile men possess substantially more spermatozoa with damaged DNA compared to fertile donors. Although the extent of this abnormality is closely related to sperm function, the underlying etiology of ensuing male infertility is still largely controversial. Both intra-testicular and post-testicular events have been postulated and different mechanisms have been proposed to explain the presence of damaged DNA in human spermatozoa. Three among them, i.e. abnormal chromatin packaging, oxidative stress and apoptosis, are the most studied and discussed in the present review. Furthermore, results from numerous investigations are presented, including our own findings on these pathological conditions, as well as the techniques applied for their evaluation. The crucial points of each methodology on the successful detection of DNA damage and their validity on the appraisal of infertile patients are also discussed. Along with the conventional parameters examined in the standard semen analysis, evaluation of damaged sperm DNA seems to complement the investigation of factors affecting male fertility and may prove an efficient diagnostic tool in the prediction of pregnancy outcome

Deformation and strength behavior of two nickel-base turbine disk alloys at 650 °c

The strength and deformation behavior of two nickel-base turbine disk alloys at 650 ° C was analyzed. The compression tests consisted of a combination of antiphase boundary (APB)-connected dislocation pairs and partials creating superlattice intrinsic stacking faults (SISF). Experimental results showed an increase in the fault density for unimodal alloys with a decrease in both particle size and strain rate

The determination of ecological quality in shallow lakes - a tested system (ECOFRAME) for implementation of the European Water Framework Directive.

1. The European Water Framework Directive requires the determination of ecological status in European fresh and saline waters. This is to be through the establishment of a typology of surface water bodies, the determination of reference (high status) conditions in each element (ecotype) of the typology and of lower grades of status (good, moderate, poor and bad) for each ecotype. It then requires classification of the status of the water bodies and their restoration to at least good status in a specified period. 2. Though there are many methods for assessing water quality, none has the scope of that defined in the Directive. The provisions of the Directive require a wide range of variables to be measured and give only general guidance as to how systems of classification should be established. This raises issues of comparability across States and of the costs of making the determinations. 3. Using expert workshops and subsequent field testing, a practicable pan-European typology and classification system has been developed for shallow lakes, which can easily be extended to all lakes. It is parsimonious in its choice of determinands, but based on current limnological understanding and therefore as cost-effective as possible. 4. A core typology is described, which can be expanded easily in particular States to meet local conditions. The core includes 48 ecotypes across the entire European climate gradient and incorporates climate, lake area, geology of the catchment and conductivity. 5. The classification system is founded on a liberal interpretation of Annexes in the Directive and uses variables that are inexpensive to measure and ecologically relevant. The need for taxonomic expertise is minimized. 6. The scheme has been through eight iterations, two of which were tested in the field on tranches of 66 lakes. The final version, Version 8, is offered for operational testing and further refinement by statutory authorities [KEYWORDS: lakes Water Framework Directive typology ecotypes ecological status quality]