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1. Evaluation of the Influence of Lorentz Forces on the Natural Frequencies of a Dual-Microcantilever Sensor for Ultralow Mass Detection

   https://doi.org/10.3390/micro4040035  

   Banchelli, Luca; Todorov, Georgi; Stavrov, Vladimir; Ganev, Borislav; Todorov, Todor (December 2024, Micro)

   In this paper, the impact of Lorentz forces and temperature on the natural frequencies of a piezoresistive sensor composed of two microcantilevers with integrated U-shaped thin-film aluminum heaters are investigated. Two types of experiments were performed. In the first, the sensor was placed in a magnetic field so that the current flowing in the heater, in addition to raising the temperature, produced Lorentz forces, inducing normal stresses in the plane of one of the microcantilevers. In the second, which were conducted without magnetic fields, only the temperature variation of the natural frequency was left. In processing of the results, the thermal variations were subtracted from the variations due to both Lorentz forces and temperature in the natural frequency, resulting in the influence of the Lorentz forces only. Theoretical relations for the Lorentz frequency offsets were derived. An indirect method of estimating the natural frequency of one of the cantilevers, through a particular cusp point in the amplitude–frequency response of the sensor, was used in the investigations. The findings show that for thin microcantilevers with silicon masses on the order of 4 × 10−7 g and currents of 25 µA, thermal eigenfrequency variations are dominant. The results may have applications in the design of similar microsensors with vibrational action. 

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2. Approaching the history of an Egyptian biomedicine

   https://doi.org/10.1111/hic3.12656  

   Derr, Jennifer L. (May 2021, History Compass)

   null (Ed.)

   This piece explores the history of medicine in Egypt, the roots of an Egyptian practice of biomedicine in particular, through its historiography. In the period after World War II, the term “biomedicine” came to describe a practice of medicine defined by the close relations among clinicians, biological laboratory research, and the pharmaceutical industry in Europe and the United States. The history of medicine in Egypt and other parts of the Middle East and North Africa has long possessed close links to that in regions of Europe. In Egypt too, biomedicine has deep historical roots shaped by the influence of the nineteenth-century Ottoman‐Egyptian state, the experience of colonialism, and the anti‐colonial objectives of the post‐colonial Egyptian state in the second half of the twentieth century. These influences were particularly important in relation to the treatment of schistosomiasis, one of Egypt's top-ranking health problems of the twentieth century. The history of schistosomiasis demonstrates the gaps in the historiography of medicine in modern Egypt as well as how we might begin to consider the emergence of biomedical knowledge and theory at sites in Global South. 

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3. “Approaching the History of an Egyptian Biomedicine”

   https://doi.org/https://doi-org.oca.ucsc.edu/10.1111/hic3.12656  

   Derr, Jennifer L. (June 2021, History compass)

   This piece explores the history of medicine in Egypt, the roots of an Egyptian practice of biomedicine in particular, through its historiography. In the period after World War II, the term “biomedicine” came to describe a practice of medicine defined by the close relations among clinicians, biological laboratory research, and the pharmaceutical industry in Europe and the United States. The history of medicine in Egypt and other parts of the Middle East and North Africa has long possessed close links to that in regions of Europe. In Egypt too, biomedicine has deep historical roots shaped by the influence of the nineteenth-century Ottoman-Egyptian state, the experience of colonialism, and the anti-colonial objectives of the post-colonial Egyptian state in the second half of the twentieth century. These influences were particularly important in relation to the treatment of schistosomiasis, one of Egypt’s top-ranking health problems of the twentieth century. The history of schistosomiasis demonstrates the gaps in the historiography of medicine in modern Egypt as well as how we might begin to consider the emergence of biomedical knowledge and theory at sites in Global South. 

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4. Spatial and Temporal Variability of Permafrost in the Western Part of the Russian Arctic

   https://doi.org/10.3390/en15072311  

   Malkova, Galina; Drozdov, Dmitry; Vasiliev, Alexander; Gravis, Andrey; Kraev, Gleb; Korostelev, Yuriy; Nikitin, Kirill; Orekhov, Pavel; Ponomareva, Olga; Romanovsky, Vladimir; et al (April 2022, Energies)

   Climate warming in the Russian Arctic over the past 40 years shows a variety of patterns at different locations and time periods. In the second half of the 20th century, the maximum rates of warming were characteristic of the subarctic permafrost regions of Russia. But in the 21st century, the locations of the greatest rates of climate warming moved to the Arctic zone of Russia. It was one of the reasons for a sharp increase in permafrost temperatures, an increase in the depth of seasonal thaw, and the formation of closed taliks. It was found that as a result of climate change, the differences in permafrost temperatures between different cryogenic landscapes in the area of continuous and discontinuous permafrost distribution have decreased, and in the area of sporadic permafrost distribution are now practically absent. The thermal regime of the ground shows dramatic changes everywhere with a pronounced reduction in the depth of zero annual amplitude. 

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5. Changes in Sharing and Participation are Important Predictors of the Health of Traditional Harvest Practices in Indigenous Communities in Alaska

   https://doi.org/10.1007/s10745-022-00342-4  

   Brinkman, Todd; Charles, Billy; Stevens, Benjamin; Wright, Brooke; John, Simeon; Ervin, Bruce; Joe, Jorene; Ninguelook, Georgianna; Heeringa, Krista; Nu, Jennifer; et al (August 2022, Human Ecology)

   Abstract The well-being of Indigenous communities in Alaska is inextricably linked to traditional harvest practices (THPs) such as hunting, fishing, and gathering local wild foods. Regional trends in the health of THPs have not been quantitatively evaluated in Alaska. Therefore, we surveyed Indigenous residents in the Western Coastal (n = 623) and Interior (n = 437) Regions of Alaska to estimate perceptions of the extent and cause of change in the health of THPs over the last ten years. We found that THPs improved in Western Coastal and declined in Interior Alaska. The best predictors of improvement or decline in the health of THPs were 1) change in the ability to share the harvest, 2) change in participation in hunting and fishing activities, and 3) extent of challenges caused by climate change. The odds of a decline in the health of THPs were 8 to 13 times higher for households that reported a decrease in sharing of traditional foods. 

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