Thermographic Imaging in Cultural Heritage: A Short Review.

Over the recent period, there has been an increasing interest in the use of pulsed infrared thermography (PT) for the non-destructive evaluation of Cultural Heritage (CH). Unlike other techniques that are commonly employed in the same field, PT enables the depth-resolved detection of different kinds of subsurface features, thus providing helpful information for both scholars and restorers. Due to this reason, several research activities are currently underway to further improve the PT effectiveness. In this manuscript, the specific use of PT for the analysis of three different types of CH, namely documentary materials, panel paintings-marquetery, and mosaics, will be reviewed. In the latter case, i.e., mosaics, passive thermography combined with ground penetrating radar (GPR) and digital microscopy (DM) have also been deepened, considering their suitability in the open field. Such items have been selected because they are characterized by quite distinct physical and structural properties and, therefore, different PT (and, in some cases, verification) approaches have been employed for their investigations.

The Influence of Sepsis on the Molecular Structure of Bones: A Fourier Transform Infrared Spectroscopy Study.

Fourier transform infrared spectroscopy was used to evaluate the molecular structure of bone tissues of patients who underwent revision of total hip and shoulder arthroplasty. The intensity increase of the spectral bands in the region of 3000-2850 cm-1 provided information about the increase of the lipophilic environment, which supported the formation of aggregates and amyloid protein formation. The appearance and the intensity increase of the "marker band" at 1744 cm-1 suggested protein peroxidation and inflammation progression. The shift of the amide I and amide II absorption bands from 1650 cm-1 and 1550 cm-1, respectively, to lower frequencies was related to changes of collagen conformation structure from α-helix to ß-sheet and random coil. The appearance and shifts of the new bands in the region 1200-900 cm-1 were related with the increasing of glycosylation upon inflammation. Important was also the disappearance of the hydroxyapatite vPO43- absorption bands at the spectral regions 1200-900 cm-1 and 550-650 cm-1 indicated the osteolysis development. Moreover, the formation of corrosive metallic implants confirmed the effect of oxidative stress on the development of periprosthetic joint infection.

FT-IR Spectroscopy Study in Early Diagnosis of Skin Cancer.

BACKGROUND/AIM: Mid-infrared spectroscopy (4000-500 cm-1) was used to analyze the spectral changes and differences of the characteristic absorption bands of the skin components due to cancer development for early clinical diagnosis. MATERIALS AND METHODS: Human biopsies from basal cell carcinoma, malignant melanoma, and nevus were used, while normal skin tissue served as a control. RESULTS: The high quality of Fourier-transform infrared (FT-IR) spectra showed that upon cancer development the intensity of the absorption band at approximately 3062 cm-1 was increased, indicating that most of the proteins had the configuration of amide B and the ß-sheet protein structure predominated. The stretching vibration bands of vCH2 in the region 2950-2850 cm-1 were increased in melanoma and nevus, while were less pronounced in basal cell carcinoma due to the increased lipophilic environment. In addition, the intensity of a new band at 1744 cm-1, which is assigned to aldehyde, was increased in melanoma and nevus and appeared as a shoulder in the spectra of normal skin. The absorption band of amide I at 1650 cm-1 was split into two bands, at 1650 cm-1 and 1633 cm-1, due to the presence of both α-helix and random coil protein conformations for melanoma and nevus. This was confirmed from the amide II band at 1550 cm-1, which shifted to lower frequencies at 1536 cm-1 and 1540 cm-1 for basal cell carcinoma and melanoma, respectively, indicating a damage of the native structure of proteins. The bands at 841 and 815 cm-1, which are assigned to B-DNA and Z-DNA, respectively, indicated that only the bands of the cancerous Z-DNA form are pronounced in melanoma, while in BCC both the characteristic bands of B-DNA and Z-DNA forms are found. CONCLUSION: It is proposed that the bands described above could be used as "diagnostic marker" bands for DNA forms, in the diagnosis of skin cancer.