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The effect of cooling rate on the intensity of low‐field thermoremanent magnetization (TRM) in uniaxial, single‐domain magnetite is calculated, using both numerical and analytical techniques. These calculations indicate that when a single‐domain assemblage is cooled much more slowly than in a typical laboratory experiment, it can remain magnetically unblocked and in thermal equilibrium with an external field at temperatures significantly lower than the ‘laboratory’ blocking temperature. Owing to the rapid rise of spontaneous magnetization just below the Curie temperature the TRM can consequently be elevated by several tens of percent over that acquired in the laboratory. The paleointensity obtained from rocks that have cooled in nature over geologic time may therefore be erroneously high, if single‐domain particles are the primary carriers of NRM. These calculations indicate that when the ratio of ‘natural’ to laboratory cooling rates approximately equals 10−11, as in the case of orogenic bodies that have cooled over several million years, the paleointensity obtained by the Thellier method can be more than 50% too high, unless the role of cooling rate is taken into account.

Similar to adults, adolescents experience a traumatic grief reaction after exposure to a peer's suicide. Clinicians should be alerted to the occurrence of traumatic grief reactions among adolescents and the need to assess these reactions and address them in their treatment approaches.

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Objective-This is an update of an earlier study on the relation between exposure to arsenic in air and deaths from respiratory cancer. The purpose was to verify earlier findings of a supralinear dose response relation and to examine relations with other cancers, particularly those reported in studies on drinking water. Methods-An earlier study of 2802 men who worked at a copper smelter for a year or more during the period 1940-64 and who were followed up for deaths during the period 1941-76 was updated until 1986. Estimates of exposure for the period 1977-1984 were added. Results and conclusions-The additional follow up confirms the earlier finding that at low doses the increments in death rates for respiratory cancer for a given increment in dose are greater than at high doses. The additional follow up also shows significant increases in cancer of the large intestine and bone, and SMRs >150 for cancer of the buccal cavity and pharynx, rectal cancer, and kidney cancer. There was a positive relation between exposure to arsenic in air and kidney and bone cancer, but none for the other cancers, except respiratory. (Occup Environ Med 1995;52:28-32)

This paper describes the occurrence of kernicterus and factors which influence its development in the strain of rats * first studied by Gunn.22,23 The disease of humans designated in 1903 by Schmorl 39 as kernicterus has, in our opinion, not been observed or induced in its entirety in animals. Various workers, however, have demonstrated the toxicity of indirect bilirubin. [12][13][14][15]24,26,[44][45][46]

Viral infections continue to cause considerable morbidity and mortality around the world. Recent rises in these infections are likely due to complex and multifactorial external drivers, including climate change, the increased mobility of people and goods and rapid demographic change to name but a few. In parallel with these external factors, we are gaining a better understanding of the internal factors associated with viral immunity. Increasingly the gastrointestinal (GI) microbiome has been shown to be a significant player in the host immune system, acting as a key regulator of immunity and host defense mechanisms. An increasing body of evidence indicates that disruption of the homeostasis between the GI microbiome and the host immune system can adversely impact viral immunity. This review aims to shed light on our understanding of how host-microbiota interactions shape the immune system, including early life factors, antibiotic exposure, immunosenescence, diet and inflammatory diseases. We also discuss the evidence base for how host commensal organisms and microbiome therapeutics can impact the prevention and/or treatment of viral infections, such as viral gastroenteritis, viral hepatitis, human immunodeficiency virus (HIV), human papilloma virus (HPV), viral upper respiratory tract infections (URTI), influenza and SARS CoV-2. The interplay between the gastrointestinal microbiome, invasive viruses and host physiology is complex and yet to be fully characterized, but increasingly the evidence shows that the microbiome can have an impact on viral disease outcomes. While the current evidence base is informative, further well designed human clinical trials will be needed to fully understand the array of immunological mechanisms underlying this intricate relationship.

Thermoremanent magnetization (TRM), the dominant mechanism in igneous rocks, has been investigated for many years, yielding a large data base of experimental results and several theoretical models. However, there are still a large number of discrepancies between the observations and the theories.The theoretical models of TRM are reviewed, and then evaluated in the light of recent experimental results from sized synthetic magnetites and titanomagnetites, and igneous rocks.