The principles of helium exploration

Commercial helium systems have been found to date as a serendipitous by-product of petroleum exploration. There are nevertheless significant differences in the source and migration properties of helium compared with petroleum. An understanding of these differences enables prospects for helium gas accumulations to be identified in regions where petroleum exploration would not be tenable. Here we show how the basic petroleum exploration playbook (source, primary migration from the source rock, secondary longer distance migration, trapping) can be modified to identify helium plays. Plays are the areas occupied by a prospective reservoir and overlying seal associated with a mature helium source. This is the first step in identifying the detail of helium prospects (discrete pools of trapped helium). We show how these principles, adapted for helium, can be applied using the Rukwa Basin in the Tanzanian section of the East African Rift as a case study. Thermal hiatus caused by rifting of the continental basement has resulted in a surface expression of deep crustal gas release in the form of high-nitrogen gas seeps containing up to 10% 4He. We calculate the total likely regional source rock helium generative capacity, identify the role of the Rungwe volcanic province in releasing the accumulated crustal helium, and show the spatial control of helium concentration dilution by the associated volcanic CO2. Nitrogen, both dissolved and as a free gas phase, plays a key role in the primary and secondary migration of crustal helium and its accumulation into what might become a commercially viable gas pool. This too is examined. We identify and discuss evidence that structures and seals suitable for trapping hydrocarbon and CO2 gases will likely also be efficient for helium accumulation on the timescale of the Rukwa basin activity.The Rukwa Basin prospective recoverable P50 resources of helium have been independently estimated to be about 138 billion standard cubic feet (2.78 x 109 m3 at STP). If this volume is confirmed it would represent about 25% of the current global helium reserve. Two exploration wells Tai 1 and Tai 2 completed by August 2021 have proved the presence of seal and reservoir horizons with the reservoirs containing significant helium shows.This article is part of the Energy Geoscience Series available at https://www.lyellcollection.org/cc/energy-geoscience-series

Secondary malposition of a PICC-port due to heavy physical exercise: A case report

Physical exercise is often encouraged in cancer patients, mainly for the purpose of rehabilitation and for its psychological benefit. Some authors also suggest that exercise—specially in patient with peripherally inserted central venous access devices—may contribute to reduce the risk of catheter-related thrombosis. Still, the impact of physical exercise on the risk of device-related complications is not yet defined. We report a case of secondary migration of the tip of an arm port, caused by high-intensity exercise in a woman undergoing chemotherapy because of ovarian cancer. Tip migration was suspected because of malfunction (persistent withdrawal occlusion) and diagnosis established after ultrasound examination and chest x-ray. Even if exercise may yield benefit in the cancer patient on chemotherapy, the risk of mechanical complication of the venous access device—such as tip migration—should be considered in the case of high-intensity exercise.

Moving around the world : Russian Jews from Israel in Toronto

This study is focused on the immigration related experiences of Russian Jews who left the Former Soviet Union for Israel in the late 1980s and early 1990s and arrived in Toronto in the late 1990s and early 2000s. It explores the unique character of this cohort, their settlement in Toronto as well as their identities and transnational practices. During the last two decades of the 20th century there has been a continuous influx of Russian Jews from Israel to Toronto. This ongoing immigrant cohort has become the major source of recent Jewish immigrants to Toronto. It is usually referred as "a secondary migration of Russian Jews". This cohort of Russian Jews has notable features which have affected their adjustment and integration in Toronto. The study draws on a variety of sources including the examination of academic literature, media articles, personal observations, and interviews with recent immigrants.

Moving around the world : Russian Jews from Israel in Toronto

This study is focused on the immigration related experiences of Russian Jews who left the Former Soviet Union for Israel in the late 1980s and early 1990s and arrived in Toronto in the late 1990s and early 2000s. It explores the unique character of this cohort, their settlement in Toronto as well as their identities and transnational practices. During the last two decades of the 20th century there has been a continuous influx of Russian Jews from Israel to Toronto. This ongoing immigrant cohort has become the major source of recent Jewish immigrants to Toronto. It is usually referred as "a secondary migration of Russian Jews". This cohort of Russian Jews has notable features which have affected their adjustment and integration in Toronto. The study draws on a variety of sources including the examination of academic literature, media articles, personal observations, and interviews with recent immigrants.

Russian immigration to Brazil in the first half of the 20th century: migration routes and adaptation patterns

In the article under consideration, the author examines three main waves of the Russian-speaking immigration to Brazil and, particularly, to the State of São Paulo and its capital of the same name, during the first half of the 20th century. The first wave refers to the period from 1921 to the late 1930s. We consider the arrival of general Wrangel’s soldiers and officers, in 1921; the resettlement of Russian-speaking farmers from Romanian Bessarabia in 1923-1930s; and the ‘secondary’ migration of Nansen refugees from Europe during the 1930s. The second wave represents the post-war subsidized migration of Russian displaced persons (DPs), and the third one is the resettlement of the Russians from China during the 1950s. The author relies on a vast number of authentic sources from public and private archives, such as Russian-language periodicals in Brazil, Brazilian regulatory acts, and interviews with the descendants of Russian emigrants. Delivering a comparative analysis of the aforementioned waves the author concludes that the patterns of the Russian speakers’ adaptation in Brazil need to be considered in the light of political and economic conditions in the country in a particular period of immigrants’ arrival. It is also noted that anti-Soviet sentiments in Brazilian politics, starting from the mid-1930s, had a negative impact on preservation of the Russian language and Russian culture in the country.

RGD Collagen for Engineering a Contractile Tissue and Cell Therapy after Myocardial Infarct

Currently, the clinical impact of cell therapy after a myocardial infarction (MI) is limited by low cell engraftment due to significant cell death, including apoptosis, in an infarcted, inflammatory, poor angiogenic environment, low cell retention and secondary migration. Cells interact with their environment through integrin mechanoreceptors that control their survival/apoptosis/differentiation/migration/proliferation. Optimizing these interactions may be a way of improving outcomes. The association of free cells with a 3D-scaffold may be a way to target their integrins. Collagen is the most abundant structural component of the extracellular matrix (ECM) and the best contractility levels are achieved with cellular preparations containing collagen, fibrin, or Matrigel (i.e. tumor extract). In the interactions between cells and ECM, 3 main proteins are recognised: collagen, laminin and RGD (Arg-Gly-Asp) peptide. The RGD plays a key role in heart development, after MI, and on cardiac cells. Cardiomyocytes secrete their own laminin on collagen. The collagen has a non-functional cryptic RGD and is thus suboptimal for interactions with associated cells. The use of a collagen functionalized with RGD may help to improve collagen biofunctionality. It may help in the delivery of paracrine cells, whether or not they are contractile, and in assisting tissue engineering a safe contractile tissue.