In the Image of Pasteur

How does an imperial lens change our view of capitalism and science in early twentieth-century France? Using the colonial expansion of the Pasteur Institutes as a case study, this article argues that French microbiologists developed both new business models and new values of masculine comportment during their time in the colonies. There the dynamic interaction between economic success and demonstration of scientific masculinity became particularly important in reshaping how Pastorians both saw the future of their institution and interpreted the meaning of its past. Against the image of the ascetic, nonprofit scientist, Pastorians in the colonies opposed an ambitious and entrepreneurial hero. After the Great War undermined the ascetic model and weakened the economic power of the metropolitan institute, colonial Pastorians were able to shape representations of the Pastorian network to the public and narrate the history of its founder as a heroic conqueror of the microbial world. Comment une optique impériale change-t-elle notre perspective sur le capitalisme et la science au début du vingtième siècle ? Prenant l'expansion coloniale des instituts Pasteur comme exemple, cet article avance que les microbiologistes français ont développé à la fois de nouveaux modèles économiques et de nouvelles valeurs du comportement masculin au cours de leur séjour dans les colonies. Ici, l'interaction dynamique entre le succès économique et la démonstration de la masculinité scientifique est devenue particulièrement importante pour remodeler à la fois la façon dont les pastoriens voyaient l'avenir de leur institution et interpretaient le sens de son passé. Contre l'image du scientifique ascétique, les pastoriens coloniaux opposaient un héros ambitieux et entreprenant. Après que la Grande Guerre a sapé le modèle ascétique et affaibli le pouvoir économique de l'Institut métropolitain, les pastoriens coloniaux ont pu façonner des représentations publiques du réseau pastorien et raconter l'histoire de son fondateur comme conquérant héroïque du monde microbien.

Eye disorders occurred in people chronically exposed to low dose radiation as the results of radiological incidents in the Southern Ural

People of several settlements in the Southern Ural have been chronically exposed to radiation caused by contamination of the area and the Techa River with radioactive waste resulted from the Kyshtym disaster and other radiation incidents in Mayak, a nuclear reprocessing plant. The ar-ticle presents results of the study of eye diseases special features in the residents of the affected territories. Two stages of the follow-up were performed from 1955 to 1965 and dominating eye disorders found in the first follow-up stage were caused by infections and parasites. In 2018 in-crease in glaucoma cases was observed: the disease was diagnosed in 3.6% of patients, chroni-cally exposed to low dose radiation, in the first stage of follow-up glaucoma was diagnosed in 0.7% of the affected people. The growth, partly, may be caused by ageing of the population. Among chronically exposed population the cataract was the frequently diagnosed disease, senile and presenile forms were the most common among the older people. In both follow-up studies opacity in the cortical layers was the most common type of the lens change (54-63% of all types of the changes).

A STUDY OF LAYERED LENS CHANGE IN THE PROCESS OF CATARACT FORMATION IN PERSONS EXPOSED TO RADIATION AS A RESULT OF RADIATION ACCIDENTS IN THE SOUTHERN URALS

Up to now there is no clear understanding of health risk and type of dose dependence for the population chronically exposed within a range of low and average dose levels (to 1Gy). In this respect studies performed in cohorts with a sufficient number of persons can have a significant potential in providing necessary information. Objective: to study peculiarities of lens opacity in exposed persons at later time after chronic radiation exposure with due account for dose impact and nonradiation factors. The study includes patients from the URCRM registry of exposed population examined by an ophthalmologist in the period 2016-2018 (total 1,377 persons). The same technique of medical examination with photofixation of lens opacity was applied to all examined individuals. A case-control technique was used to conduct the study. Individual exposure doses to lens were calculated on the basis of TRDS-2016 for the first time within the framework of the present study. As a result of the performed study among persons exposed to long-term ionizing low-dose radiation we have determined an exposure dose impact on risk growth of opacity in the posterior capsule and lens nucleus. No reliable statistical dependence of lens change with an increasing exposure dose in anterior capsule and cortical layers as well as colour change of the lens nucleus was obtained. Belonging to different ethnical groups showed no impact on priority opacification development in any lens layers.

Gravitational Lensing of Millisecond Pulsars

Gravitational lensing can significantly magnify the images of astrophysical sources, but only if the source lies within the Einstein ring of the lens. In consequence the chance of any Galactic star magnifying a more distant source is extremely small—much less than one in a million. However, the extra light travel time (‘Shapiro delay’) introduced by the presence of a lens can be large even when there is negligible effect on the image magnification, and as the relative positions of source and lens change so does the delay. In this paper we quantify these changes and the corresponding influence on apparent timing properties of pulsars. While the total Shapiro delay can be large, it is the temporal variations in this quantity which are measurable with pulsar timing. We find that the magnitude of the expected delay variations is too small to be detectable except during strong lensing events, which are extremely rare. Even in the case of a high-velocity pulsar in the Galactic Plane, the stochastic Shapiro delay is typically expected not to have a substantial influence on the timing properties. In consequence the viability of a pulsar-based time standard is not adversely affected by gravitational lensing.