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This article describes a quantitative assessment method proposed to quickly identify the degree of deterioration of hardened leather artefacts. We used three techniques to artificially age samples, namely, dry-heat ageing (DH), UV-ageing (UV), and alkali-thermal ageing (AT). The deterioration mechanisms were studied via thermogravimetry/derivative thermogravimetry (TG/DTG) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Combined with amide III band deconvolution and second derivative fitting, we constructed a method for assessing the degree of deterioration by the relative content of random coils (referred to as R) in the secondary structure of the protein. The results show that with increasing ageing time, the macrostructures and microstructures of the leather changed to varying degrees. This study elucidates the differential behaviour of vegetable-tanned leather collagen under oxidative and hydrolytic mechanisms. Based on the deterioration characteristics and fitting results, we divided the hardened leather into the following three levels. Mild deterioration: 0 ≤ R ≤ 5%; leather with reduced pores and slight dryness and hardness but with a stable collagen structure; if the β-sheet content is ≥ 68% at this point, the leather may be recrosslinked by ultraviolet irradiation. Moderate deterioration: 6 ≤ R ≤ 25%; partial hydrogen bond breaking in leather, loosening of the collagen–tan matrix, dry and hard curling of the leather surface, and fibre cementation. Severe deterioration: R ≥ 40%, β-sheet ≤ 24%, and the α-helix is higher; surface reflection, severe macroscopic deformation and embrittlement, and the breakdown and gelatinization of the three-stranded helical structure of leather proteins. The quantitative analysis method was suitable for studying the deterioration mechanisms and assessing the degree of deterioration in Heishanling leather artefacts, which also provides a new practical scheme for assessing the degree of hardened leather. [ABSTRACT FROM AUTHOR]

Abstract This article describes a quantitative assessment method proposed to quickly identify the degree of deterioration of hardened leather artefacts. We used three techniques to artificially age samples, namely, dry-heat ageing (DH), UV-ageing (UV), and alkali-thermal ageing (AT). The deterioration mechanisms were studied via thermogravimetry/derivative thermogravimetry (TG/DTG) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Combined with amide III band deconvolution and second derivative fitting, we constructed a method for assessing the degree of deterioration by the relative content of random coils (referred to as R) in the secondary structure of the protein. The results show that with increasing ageing time, the macrostructures and microstructures of the leather changed to varying degrees. This study elucidates the differential behaviour of vegetable-tanned leather collagen under oxidative and hydrolytic mechanisms. Based on the deterioration characteristics and fitting results, we divided the hardened leather into the following three levels. Mild deterioration: 0 ≤ R ≤ 5%; leather with reduced pores and slight dryness and hardness but with a stable collagen structure; if the β-sheet content is ≥ 68% at this point, the leather may be recrosslinked by ultraviolet irradiation. Moderate deterioration: 6 ≤ R ≤ 25%; partial hydrogen bond breaking in leather, loosening of the collagen–tan matrix, dry and hard curling of the leather surface, and fibre cementation. Severe deterioration: R ≥ 40%, β-sheet ≤ 24%, and the α-helix is higher; surface reflection, severe macroscopic deformation and embrittlement, and the breakdown and gelatinization of the three-stranded helical structure of leather proteins. The quantitative analysis method was suitable for studying the deterioration mechanisms and assessing the degree of deterioration in Heishanling leather artefacts, which also provides a new practical scheme for assessing the degree of hardened leather. Graphical Abstract

Human skeletal remains exhumated from the post-war multiple grave in Souhthern Estonia were anthropologically analysed. Conventional ageing and sexing methods were used to esimate biological sex and age at death of buried people. The blind test was carried out by two independent researchers; the obtained results were compared with historic data concerning the chronological age at death and the sex of buried people. [ABSTRACT FROM AUTHOR]

The separation of animals into age classes is often fraught with difficulties, but is essential for the interpretation of survival rates and population structure. This study investigated both live hedgehogs and road kill in order to develop techniques that could be utilised to separate age classes in the field. Body measurements were taken from 24 live hedgehogs caught at a site in County Cork, Ireland over a three year period. Additionally, carcasses from around Ireland were collected and measured. There was a significant correlation between the weight and hind foot length of both live and dead hedgehogs. The weight of individuals was also significantly correlated with the body length and jaw length of hedgehogs. In all of these correlations, the sample clustered clearly into two groups with 'juveniles' meeting all of the following criteria: a hind foot length of <3.6 cm, a body length of < 16 cm and a jaw length of below 4.5 cm. It is suggested that these parameters, combined with the presence of growing spines, could provide a way of separating age classes in the field. This would be of particular benefit to short term studies, allowing the population structure to be accurately assessed and the reproductive success and sustainability of a population to be investigated. Road kill were also aged using the dentary bone in order to investigate the age profiles of hedgehogs killed on the road. Amongst those killed, 54 % of hedgehogs were 1-year-old or less. The majority of hedgehogs (87 %) were between 0-3-years-old, the oldest females were nine ( n = 2), and the oldest males were eight years old ( n = 2), respectively. Road kill hedgehogs had an average longevity of 1.94 years, and the mean age of females was higher (2.10 years) than males (1.87 years). [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, we report results of the pilot study in which we apply skeletochronological analysis of teeth to a collection of modern Chinese wild boar ( Sus scrofa) of known age and date of death. This is the first time that odontochronology has been applied to suids in China. This work allowed us to establish parameters for subsequent analysis of a limited number of Neolithic-aged Sus (wild boar and possible early domesticated pig) samples from Henan Province. The goal of the research is to contribute to the ongoing reconstruction of Neolithic dietary, health and economic patterns along the Yellow River. Our results are encouraging in that regular seasonal growth patterning is observed in the northern control sample, which is from the same region as our archaeological investigation. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The discovery thirty years ago of daily growth increments in squid statoliths and the development of statolith ageing techniques gave new insight into squid age, growth and metabolism. The techniques have shown that the majority of recent coleoid cephalopods live in the ‘fast lane’, growing rapidly and completing their life cycles in a year or less. Surprisingly, these useful approaches to the study of age and growth in squid have not gained much momentum. Only approximately an eighth of more than 300 squid species have had their basic age assessed and described. Two dozen species are subject to continuing arguments about which increments to consider as daily growth increments. This paper outlines major problems encountered during age determination of squid and suggests ways to improve the techniques and make them applicable to a wider spectrum of species. [ABSTRACT FROM PUBLISHER]

1. Absolute age was estimated from incremental bone layers of the mandible in 109 edible dormiceGlis gliscollected between May and September 1997 in mixed beech and fir forests of central Slovenia.2. Mandible cross-sections of juveniles obtained in September showed a great number of vascular canals and no resting lines. In the remaining animals (n = 81), the number of resting lines varied between one and seven, with two or three lines being the most common condition (62% of specimens). Among these adult animals, which hibernated at least once, females attained higher mean (3.3 years) and maximum age (7 years) than males (mean = 2.2, maximum = 6 years).3. The frequency distribution of age classes suggested unequal reproductive success between years but there was no indication of any lack of litters in years of low mast production. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to supply the first information on age and growth for Thunnus obesus caught in the equatorial south-western Atlantic using dorsal spines, an approach that has been successfully employed for ageing tuna species. The study was conducted using a multi-model inference based on information theory for back-calculated and observed length-at-age data. Uncertainty associated with the parameter estimation was verified and results were compared to other accounts on the species, considering both the statistical and methodological contexts. Samples were collected in Natal city (Rio Grande do Norte State, Brazil) from February 1999 to January 2000, of tuna vessels and from surveys, aimed at providing information on the Brazilian Exclusive Economic Zone (EEZ) in the area around São Pedro and São Paulo Archipelago. Validation using marginal increment indicated that one ring is deposited per year. Mean length-at-age ranged of 54.3 to 177.5 cm (fork length) for ages 1 to 9 years. Von Bertalanffy, Richards, and Gompertz models were considered suitable for the bigeye tuna. Hence, the model-averaged asymptotic length ¯L∞ was estimated. The averaged model generated in the present study by back-calculation was considered appropriate for describing the growth of T. obesus.