Using the Smith-Watson-Topper Parameter and Its Modifications to Calculate the Fatigue Life of Metals: The State-of-the-Art.

The Smith-Watson-Topper parameter (SWT) in its original form was designed to estimate the fatigue life of metal materials in a uniaxial load state (tension-compression) in the range up to fatigue crack initiation, with non-zero mean values. This parameter is based on the analysis of both stress and strain. Therefore, the stress-strain criterion is the focus, rather than the energy criterion.

Fatigue Prediction of Aluminum Alloys Considering Critical Plane Orientation under Complex Stress States.

This publication is intended to present a new way of estimating the fatigue life of various construction materials. Carpinteri's proposal was modified by replacing the fatigue limits ratio with the value of the normal to shear stress ratio for a given number of cycles. In this study, the proposed criterion and calculation model was verified for the selected group of aluminium alloys.

Disturbances in primary dental enamel in Polish autistic children.

Dental enamel is a structure that is formed as a result of the regular functioning of ameloblasts. The knowledge of the patterns of enamel secretion allows an analysis of their disruptions manifested in pronounced additional accentuated lines. These lines represent a physiological response to stress experienced during enamel development.

Neonatal line width in deciduous incisors from Neolithic, mediaeval and modern skeletal samples from north-central Poland.

The neonatal line is usually the first accentuated incremental line visible on the enamel. The prenatal environment significantly contributes to the width of the neonatal line, influencing the pace of reaching post-delivery homeostasis by the newborn's organism. Studies of the enamel of the earliest developing deciduous teeth can provide an insight into the prenatal development and the perinatal conditions of children of past human populations, thus being an additional source contributing to consideration of the influence of prenatal and perinatal factors modifying growth processes.

Accentuated lines in the enamel of primary incisors from skeletal remains: A contribution to the explanation of early childhood mortality in a medieval population from Poland.

Physiological disruptions resulting from an impoverished environment during the first years of life are of key importance for the health and biological status of individuals and populations. Studies of growth processes in archaeological populations point to the fact that the main causes of childhood mortality in the past are to be sought among extrinsic factors. Based on this assumption, one would expect random mortality of children, with the deceased individuals representing the entire subadult population.

Mother's trauma during pregnancy affects fluctuating asymmetry in offspring's face.

Objective: Fluctuating asymmetry (FA) of paired body structures is considered to be a reliable measurement of developmental instability of humans. The aim of the study is to examine whether the mother's traumatic experience during pregnancy results in an increase of the level of fluctuating asymmetry of the structures of the face.

Methods: Average relative FA of six cephalometric traits was calculated in 269 boys aged 7-10 years from Lodz, Poland.

Pattern of dental caries in the historical human population of Kujawy in the Polish lowland (north-central Poland).

The aim of this study was to determine the dental caries rates in the skeletal human population who lived in north-central Poland in modern times (16th-18th century). The material consisted of 297 skeletons (4,783 permanent teeth) from the archeological site of K. Compared material was coming from two different sites located in the same region: early mediaeval Kolonia--39 skeletons and Swiety Duch (dating to the same historical period as K population)--417 skeletons.