Apollo 17 EVA-1 and EVA-2 Task Decomposition: Planning for Artemis and Future Mars Missions

A decomposition of the Apollo 17 mission extravehicular activities (EVA) tasks can be used to prepare for Artemis and future Mars missions. A categorized minute by minute breakdown of the astronauts activites could be used to plan future EVAs and determine which scientific tasks or equipment may be prioritized. This is especially relevant in this critical stage for the upcoming Atemis missions and science activity planning. The infographics generated from the decomposition provide a higher level view of actual EVAs and could aid in making future EVAs more efficient and successful

Scattering of particles by radiation fields: a comparative analysis

The features of the scattering of massive neutral particles propagating in the field of a gravitational plane wave are compared with those characterizing their interaction with an electromagnetic radiation field. The motion is geodesic in the former case, whereas in the case of an electromagnetic pulse it is accelerated by the radiation field filling the associated spacetime region. The interaction with the radiation field is modeled by a force term entering the equations of motion proportional to the 4-momentum density of radiation observed in the particle's rest frame. The corresponding classical scattering cross sections are evaluated too.Comment: 13 pages, 1 figure; published versio

Tobacco seedling production

Production of a high quality crop of tobacco begins in the seedbed, and it is therefore essential that the utmost care and attention be given to this stage of the crop. In general, it has been found that it is better to grow one\u27s own seedlings, rather than rely on those from an outside source, thus ensuring that strong, healthy seedlings of the correct variety and strain are available at the time of transplanting

The prevention of sucker growth of tobacco after topping

Experiments conducted overseas and elsewhere in Australia have shown that the application of mineral oils to the cut surface of the tobacco stem after topping (removal of the flower head) have reduced the amount of sucker growth of tobacco plants. Previous experience in Western Australia has shown that the most appropriate time for topping of tobacco crops has been after the first leaf has been harvested. This operation has the effect of putting more body and width into the tip leaves, which, without topping, tend to be narrow and comparatively light in weight. With late planted crops, however, crops are generally left untopped, since the topping operation tends to retard the ripening of leaf by several weeks, although, after this period, the leaves ripen more rapidly and evenly

Season reminders

Now that the sales are over, growers should be ready to take good care of the tobacco seedlings for next season\u27s crop. A good stand of healthy seedlings goes a long way towards an even crop, and is the first step towards better tobacco

New approaches for estimating risk from exposure to diethylstilbestrol.

A subgroup from a National Institute of Environmental Health Sciences, workshop concerned with characterizing the effects of endocrine disruptors on human health at environmental exposure levels considered the question, If diethylstilbestrol (DES) were introduced into the market for human use today and likely to result in low-dose exposure of the human fetus, what would be required to assess risk? On the basis of an analysis of the quality of data on human DES exposure, the critical times and doses for inducing genital tract malformations and cancer must be determined. This would be facilitated through analysis of the ontogeny of estrogen receptor expression in the developing human genital tract. Models of low-dose estrogenic effects will have to be developed for human and rodent genital tract development. Mouse models offer many advantages over other potential animal models because of the wealth of the earlier literature, the availability of sensitive end points, the availability of mutant lines, and the possibility of generating genetically engineered model systems. Through multidisciplinary approaches, it should be possible to elucidate the cellular and molecular mechanisms of endocrine disruption elicited by estrogens during development and facilitate an assessment of risk to humans

The behaviour of tobacco varieties in Western Australia

With the advent of a number of new varieties into the district, several problems have arisen, and this article is being written in an endeavour to set down just what is known of the varieties being tested. In order to make definite recommendations regarding a certain variety of tobacco, it requires to be tested under a wide range of soil and climatic conditions. To cover as wide a range of weather conditions as possible, the variety needs to be grown for three years before any real recommendation is warranted. To cover a wide range of soil types, trials have been conducted in several areas over the past two years and results are being accumulated