scholarly journals The Gravitational Zones of Influence of the Planets Acting on Small Celestial Bodies

1985 ◽  
Vol 85 ◽  
pp. 377-380
Author(s):  
N.Y. Misconi ◽  
E.T. Rusk
Keyword(s):  
Interplanetary Dust ◽  
Gravitational Acceleration ◽  
The Sun ◽  
Orbital Elements ◽  
Gravitational Forces ◽  
Celestial Bodies ◽  
Zone Of Influence ◽  
Definition Of

AbstractTisserand’s definition of the “sphere of action” of a planet is based on the equality of tidal vs. gravitational acceleration ratios of the sun and planet. Öpik and others based their relation on equating the differential solar and planetary forces on a particle. Neither expression was formulated to describe the zone of influence surrounding a planet when considering the small, but significant, long-term perturbative effects of the planets on a particle’s orbital elements. For the purpose of determining these effects on interplanetary dust we derive a zone of influence based on equating the gravitational forces of the sun and planet.

scholarly journals The orbital evolution of meteor streams at the 2/1 resonance with Jupiter

1985 ◽  
Vol 83 ◽  
pp. 179-180
Author(s):  
Cl. Froeschlé
Keyword(s):  
Major Axis ◽  
Orbital Evolution ◽  
The Sun ◽  
Orbital Elements ◽  
Meteor Stream ◽  
Semi Major Axis ◽  
Meteor Streams ◽  
Gravitational Forces ◽  
Resonant Effect

We investigated the orbital evolution of Quadrantid-like meteor streams situated in the vicinity of the 2/1 resonance with Jupiter. For the starting orbital elements we took the values of the orbital elements of the Quadrantid meteor stream except for the semi-major axis which was varied between a = 3.22 and a = 3.34 AU. We considered these meteor streams as a ring and we investigated the resonant effect on the dispersion of this ring over a period of 13 000 years. Only gravitational forces due to the Sun and due to Jupiter were taken into account.

Introduction

2018 ◽  
Author(s):  
E. L. Wolf
Keyword(s):  
Sea Level ◽  
Quantum Physics ◽  
Fossil Fuels ◽  
The Sun ◽  
Earth System ◽  
System Quantum ◽  
Carbon Dioxide Levels ◽  
Definition Of ◽  
Earth Temperature

An introduction to long-term climate-neutral energy makes clear that most arises from the Sun or the motions of the Sun-Earth system. Quantum physics is an essential part of understanding the Sun’s energy source, nuclear fusion. The expected depletion times of oil and other fossil fuels are discussed. The most recent 500,000 years of Earth temperature and sea level are surveyed and shown to correlate closely with carbon dioxide levels in the atmosphere. Sea level and temperature are correlated and move together on time scales of five thousand years. The definition of sustainable energy, the topic of this textbook, is very straightforward. This is the energy that will be available on (after) a timescale set by the earliest benchmarks of our civilization, let us say the timescale of the earliest pyramids or the Chinese Wall, visible from space.

Central Otago - Built on gold, growing on grass.

2014 ◽  
Vol 76 ◽  
pp. 15-23
Author(s):  
Barrie J. Wills
Keyword(s):  
Economic Growth ◽  
Land Use ◽  
National Economy ◽  
Local Community ◽  
Central Government ◽  
Future Generations ◽  
Economic Potential ◽  
District Council ◽  
Definition Of

A warm welcome to our "World of Difference" to all delegates attending this conference - we hope your stay is enjoyable and that you will leave Central Otago with an enhanced appreciation of the diversity of land use and the resilient and growing economic potential that this region has to offer. Without regional wellbeing the national economy will struggle to grow, something Central Government finally seems to be realising, and the Central Otago District Council Long Term Plan 2012-2022 (LTP) signals the importance of establishing a productive economy for the local community which will aid in the economic growth of the district and seeks to create a thriving economy that will be attractive to business and residents alike. Two key principles that underpin the LTP are sustainability and affordability, with the definition of sustainability being "… development that meets the needs of the present without compromising the ability of future generations to meet their own needs."

Populism and Liberal Democracy

2019 ◽  
Author(s):  
Takis S. Pappas
Keyword(s):  
United States ◽  
Liberal Democracy ◽  
The United States ◽  
Comprehensive Theory ◽  
The People ◽  
Original Definition ◽  
Key Issues ◽  
Great Relevance ◽  
Definition Of

Based on an original definition of modern populism as “democratic illiberalism” and many years of meticulous research, Takis Pappas marshals extraordinary empirical evidence from Argentina, Greece, Peru, Italy, Venezuela, Ecuador, Hungary, the United States, Spain, and Brazil to develop a comprehensive theory about populism. He addresses all key issues in the debate about populism and answers significant questions of great relevance for today’s liberal democracy, including: • What is modern populism and how can it be differentiated from comparable phenomena like nativism and autocracy? • Where in Latin America has populism become most successful? Where in Europe did it emerge first? Why did its rise to power in the United States come so late? • Is Trump a populist and, if so, could he be compared best with Venezuela’s Chávez, France’s Le Pens, or Turkey’s Erdoğan? • Why has populism thrived in post-authoritarian Greece but not in Spain? And why in Argentina and not in Brazil? • Can populism ever succeed without a charismatic leader? If not, what does leadership tell us about how to challenge populism? • Who are “the people” who vote for populist parties, how are these “made” into a group, and what is in their minds? • Is there a “populist blueprint” that all populists use when in power? And what are the long-term consequences of populist rule? • What does the expansion, and possibly solidification, of populism mean for the very nature and future of contemporary democracy? Populism and Liberal Democracy will change the ways the reader understands populism and imagines the prospects of liberal democracy.

scholarly journals “I’ve Heard of It, Yes, but I Can’t Remember What Exactly It Was”—A Qualitative Study on Awareness, Knowledge, and Use of the UV Index

2021 ◽  
Vol 18 (4) ◽  
pp. 1615
Author(s):  
Katharina Diehl ◽  
Tatiana Görig ◽  
Charlotte Jansen ◽  
Maike Carola Hruby ◽  
Annette B. Pfahlberg ◽  
...  
Keyword(s):  
Qualitative Study ◽  
Qualitative Content Analysis ◽  
Sun Protection ◽  
Structured Interviews ◽  
Protection Factor ◽  
Protection Measures ◽  
Uv Index ◽  
Correct Definition ◽  
Definition Of

Pharmacists and pharmaceutical technicians play an important role in counselling customers regarding sunscreen use and sun protection measures. A potentially helpful tool that can be used during counselling is the ultraviolet index (UVI), which informs individuals when and what sun protection measures are needed at a specific place and time. Our aim in this qualitative study was to explore awareness, knowledge, and use of the UVI during counselling in pharmacies. We used semi-structured interviews with pharmacists and pharmaceutical technicians (n = 20) to answer our research questions. Interviews were audiotaped, transcribed verbatim, and analyzed using qualitative content analysis. During the interviews pharmacists and pharmaceutical technicians revealed a lot of uncertainty and lack of knowledge regarding the UVI. Eight professionals were able to give a correct definition of UVI. Amongst others, the UVI was confused with sun protection factor. Overall, the UVI was hardly used during the counselling of customers. The UVI was developed to provide guidance when which type of sun protection is required to avoid detrimental effects of ultraviolet radiation. For effective implementation, both the general population and health professionals (e.g., pharmacists) have to increase their knowledge about the UVI. This would strengthen its use during professional counselling in pharmacies and may help to reduce the incidence of skin cancer over the long term.

scholarly journals Extended analytical formulae for the perturbed Keplerian motion under low-thrust acceleration and orbital perturbations

2021 ◽  
Vol 133 (3) ◽  
Author(s):  
Marilena Di Carlo ◽  
Simão da Graça Marto ◽  
Massimiliano Vasile
Keyword(s):  
Gravitational Perturbation ◽  
Low Thrust ◽  
Orbital Elements ◽  
Third Body ◽  
The Third ◽  
Orbital Perturbations ◽  
Analytical Formulae ◽  
Numerical Orbit ◽  
Body Potential

AbstractThis paper presents a collection of analytical formulae that can be used in the long-term propagation of the motion of a spacecraft subject to low-thrust acceleration and orbital perturbations. The paper considers accelerations due to: a low-thrust profile following an inverse square law, gravity perturbations due to the central body gravity field and the third-body gravitational perturbation. The analytical formulae are expressed in terms of non-singular equinoctial elements. The formulae for the third-body gravitational perturbation have been obtained starting from equations for the third-body potential already available in the literature. However, the final analytical formulae for the variation of the equinoctial orbital elements are a novel derivation. The results are validated, for different orbital regimes, using high-precision numerical orbit propagators.

scholarly journals III. On the nature and construction of the sun and fixed stars

1795 ◽  
Vol 85 ◽  
pp. 46-72 ◽  
Keyword(s):  
Central Body ◽  
Planetary System ◽  
Considerable Progress ◽  
The Sun ◽  
Great Satisfaction ◽  
The Earth ◽  
The World ◽  
Celestial Bodies ◽  
The Universe ◽  
Made In

Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which main­tains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.

scholarly journals It Is Not Just Mortality: A Call From Chile for Comprehensive COVID-19 Policy Responses Among Older People

2020 ◽  
Author(s):  
Pablo Villalobos Dintrans ◽  
Jorge Browne ◽  
Ignacio Madero-Cabib
Keyword(s):  
Older People ◽  
National Level ◽  
Health Issues ◽  
Negative Consequences ◽  
Access To Health Services ◽  
Term Care ◽  
Policy Responses ◽  
Level Data ◽  
Definition Of

Abstract Objective Provide a synthesis of the COVID-19 policies targeting older people in Chile, stressing their short- and long-term challenges. Method Critical analysis of the current legal and policy measures, based on national-level data and international experiences. Results Although several policies have been enacted to protect older people from COVID-19, these measures could have important unintended negative consequences in this group’s mental and physical health, as well as financial aspects. Discussion A wider perspective is needed to include a broader definition of health—considering financial scarcity, access to health services, mental health issues, and long-term care—in the policy responses to COVID-19 targeted to older people in Chile.

scholarly journals Cycles and circulation: a theme in the history of biology and medicine

2021 ◽  
Vol 43 (3) ◽  
Author(s):  
Nick Hopwood ◽  
Staffan Müller-Wille ◽  
Janet Browne ◽  
Christiane Groeben ◽  
Shigehisa Kuriyama ◽  
...  
Keyword(s):  
Natural Philosophy ◽  
Life Cycles ◽  
Modern Times ◽  
Systems Ecology ◽  
The Face ◽  
History Of ◽  
Celestial Bodies ◽  
Reproductive Cycles ◽  
Economics And Biology

AbstractWe invite systematic consideration of the metaphors of cycles and circulation as a long-term theme in the history of the life and environmental sciences and medicine. Ubiquitous in ancient religious and philosophical traditions, especially in representing the seasons and the motions of celestial bodies, circles once symbolized perfection. Over the centuries cyclic images in western medicine, natural philosophy, natural history and eventually biology gained independence from cosmology and theology and came to depend less on strictly circular forms. As potent ‘canonical icons’, cycles also interacted with representations of linear and irreversible change, including arrows, arcs, scales, series and trees, as in theories of the Earth and of evolution. In modern times life cycles and reproductive cycles have often been held to characterize life, in some cases especially female life, while human efforts selectively to foster and disrupt these cycles have harnessed their productivity in medicine and agriculture. But strong cyclic metaphors have continued to link physiology and climatology, medicine and economics, and biology and manufacturing, notably through the relations between land, food and population. From the grand nineteenth-century transformations of matter to systems ecology, the circulation of molecules through organic and inorganic compartments has posed the problem of maintaining identity in the face of flux and highlights the seductive ability of cyclic schemes to imply closure where no original state was in fact restored. More concerted attention to cycles and circulation will enrich analyses of the power of metaphors to naturalize understandings of life and their shaping by practical interests and political imaginations.

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