There is still controversy over whether analytical techniques currently in use are able to identify the level of damage to spermatozoa. Large-scale studies should be conducted in different clinical settings to determine the effects of sperm DNA damage on the outcome of ART.

Many porous materials are damaged by pressure exerted by salt crystals growing in their pores. This is a serious issue in conservation science, geomorphology, geotechnical engineering and concrete materials science. In all cases, a central question is whether crystallization pressure will cause damage. Here we present an experiment in which the crystallization pressure and the pore saturation are varied in a controlled way. We demonstrate that a strain energy failure criterion can be used to predict when damage will occur. The experiment considered is the most widely used means to study the susceptibility to salt crystallization, so quantification of this test has far-reaching implications.

Chloride ingress can lead to serious degradation of various materials and structures. Continuous measurements of local chloride concentrations is thus of uttermost importance for laboratory research, monitoring of structures, and predictions of the residual life span for the most common building materials. This work investigates the applicability of Ag/AgCl ion-selective electrodes for the non-destructive continuous measurement of local chloride concentrations in concrete and stone when exposed to chloride-bearing environments such as seawater. The work studies the stability of Ag/AgCl ion-selective electrodes in neutral and alkaline solutions and the sensitivity to the main interfering ions coming from the environment and from the material itself. The results indicate negligible interference from fluoride, sulfate, and hydroxyl but considerable from bromide and sulfide. In chloride-free alkaline solutions, Ag/ AgCl ion-selective electrodes are not stable over time, but-upon chloride arrival-they permit again reliable measurements of the chloride concentration. The results concerning interference are discussed by taking into account typical exposure environments and it is concluded that the ion-selective electrodes can satisfactorily be used to monitor chloride concentrations in built structures made out of concrete or stone.

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Salt crystallization represents one of the major causes for the degradation of building and ornamental stone. As such, it has attracted the attention of researchers, who over the years have progressively unraveled most mechanisms involved in salt damage. Despite this mechanistic understanding, many questions subsist about how to quantitatively predict damage or its progression, and in particular how to relate performance on site to that in laboratory tests. In this context, a new RILEM TC 271-ASC has been started with the objective of defining laboratory tests that deliver more reliable predictions of field behavior. One deliverable of this TC is to provide a theoretical insight into this question based on recent progress on the understanding of salt damage. This paper presents a summary of this work, highlighting key aspects relating to crystallization pressure, chemo-mechanics and mass transport. Implications are discussed in relation to the most used accelerated salt crystallization tests in an attempt to better define which field exposure conditions that these tests best represent and may be used for, or define effective test procedures representing specific field conditions. A simple conceptual model for the development of salt damage is introduced. During an initial "induction" phase, transport of ions and accumulation of salt in the porous materials occurs without causing detectable damage until a critical point, termed "damage onset" is reached. Beyond this point, during the "propagation phase", the material degrades, typically losing strength and cohesiveness. The implications of these two phases are discussed in relation to the selection of appropriate salt weathering tests and conservation interventions.

In 2008 the rostrum from an ancient warship was recovered from the Mediterranean near Acqualadrone, Sicily. To establish its provenance and condition, samples of black and brown rostrum wood were examined using sulfur K-edge x-ray absorption spectroscopy (XAS) and GC-MS. GC-MS of pyrolytic volatiles yielded only guaiacyl derivatives, indicating construction from pinewood. A derivatized extract of black wood yielded forms of abietic acid and sandaracopimaric acid consistent with pine pitch waterproofing. Numerical fits to the sulfur K-edge XAS spectra showed that about 65% of the endogenous sulfur consisted of thiols and disulfides. Elemental sulfur was about 2% and 7% in black and brown wood, respectively, while pyritic sulfur was about 12% and 6%. About 2% of the sulfur in both wood types was modeled as trimethylsulfonium, possibly reflecting biogenic dimethylsulfonio-propionate. High valent sulfur was exclusively represented by sulfate esters, consistent with bacterial sulfotransferase activity. Traces of chloride were detected, but no free sulfate ion. In summary, the rostrum was manufactured of pine wood and subsequently waterproofed with pine pitch. The subsequent 2300 years included battle, foundering, and marine burial followed by anoxia, bacterial colonization, sulfate reduction, and mobilization of transition metals, which produced pyrite and copious appended sulfur functionality.

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