scholarly journals Visibility: How Applicable is the Century-Old Koschmieder Model?

2016 ◽  
Vol 73 (11) ◽  
pp. 4573-4581 ◽  
Author(s):  
Zhongping Lee ◽  
Shaoling Shang
Keyword(s):  
Radiative Transfer ◽  
Extinction Coefficient ◽  
Daily Life ◽  
Weather Conditions ◽  
Angular Dimension ◽  
Past Century ◽  
The Past ◽  
Simple Detection ◽  
Clear Identification ◽  
Contrast Reduction

Abstract Koschmieder proposed that visibility is inversely proportional to the extinction coefficient of air, and this model has been widely adopted during the past century. Using radiative transfer theory, the authors present a general relationship for the law of contrast reduction and point out that the Koschmieder model is workable only to situations when a common-size object can be viewed tens of kilometers away. However, the Koschmieder model is not applicable for viewable distances of hundreds of meters when the angular dimension of an object is significantly greater than the eye resolution of the human being. The authors further separate the term “visible” into “simple detection” or “detectability” and “clear identification” or “identifiability” and point out that the Koschmieder model is applicable to identifiability, but not necessarily for detectability. In addition, the way of calculating contrast is revised to follow the concept of brightness constancy. The results of this effort advocate the measurement and distribution of detectability in harsh weather conditions, as such data offer more useful and important information for daily life.

scholarly journals American Meteorological Society: 100 Years of Supporting the Scientific Community

2018 ◽  
Vol 59 ◽  
pp. 1.1-1.23 ◽  
Author(s):  
Keith L. Seitter ◽  
Jinny Nathans ◽  
Sophie Mankins
Keyword(s):  
Scientific Community ◽  
Daily Life ◽  
Professional Society ◽  
Past Century ◽  
Profound Impact ◽  
The Past ◽  
American Meteorological Society ◽  
Strategic Initiatives ◽  
Key Points ◽  
Dissemination Of Research

Abstract Over the past century, the atmospheric and related sciences have seen incredible advances in our understanding of Earth’s environment and our ability to monitor and predict its behavior. These advances have had a profound impact on society and have been integrated into every aspect of daily life. The American Meteorological Society (AMS) has been instrumental in supporting these advances throughout its first 100 years of existence as a scientific and professional society serving the community of professionals in the atmospheric and related oceanic and hydrologic sciences. AMS has provided opportunities for researchers and practitioners to share their scientific findings and build fruitful collaborations to further the science and its application. Through strategic initiatives at key points in its history, AMS has pushed the science forward—highlighting areas ripe for development, creating frameworks for interdisciplinary interactions, and providing innovative approaches to the dissemination of research results. As a society made up of the scientific community and led by many of the most prominent scientists of their time, AMS has been able to respond to, and often anticipate, the needs of its community.

The zoonotic potential of bat-borne coronaviruses

2020 ◽  
Vol 4 (4) ◽  
pp. 365-381
Author(s):  
Ny Anjara Fifi Ravelomanantsoa ◽  
Sarah Guth ◽  
Angelo Andrianiaina ◽  
Santino Andry ◽  
Anecia Gentles ◽  
...  
Keyword(s):  
Genetic Material ◽  
Field Research ◽  
Sympatric Species ◽  
Animal Origin ◽  
Mammalian Host ◽  
Past Century ◽  
The Past ◽  
Novel Host ◽  
Horseshoe Bat ◽  
Human Infections

Seven zoonoses — human infections of animal origin — have emerged from the Coronaviridae family in the past century, including three viruses responsible for significant human mortality (SARS-CoV, MERS-CoV, and SARS-CoV-2) in the past twenty years alone. These three viruses, in addition to two older CoV zoonoses (HCoV-229E and HCoV-NL63) are believed to be originally derived from wild bat reservoir species. We review the molecular biology of the bat-derived Alpha- and Betacoronavirus genera, highlighting features that contribute to their potential for cross-species emergence, including the use of well-conserved mammalian host cell machinery for cell entry and a unique capacity for adaptation to novel host environments after host switching. The adaptive capacity of coronaviruses largely results from their large genomes, which reduce the risk of deleterious mutational errors and facilitate range-expanding recombination events by offering heightened redundancy in essential genetic material. Large CoV genomes are made possible by the unique proofreading capacity encoded for their RNA-dependent polymerase. We find that bat-borne SARS-related coronaviruses in the subgenus Sarbecovirus, the source clade for SARS-CoV and SARS-CoV-2, present a particularly poignant pandemic threat, due to the extraordinary viral genetic diversity represented among several sympatric species of their horseshoe bat hosts. To date, Sarbecovirus surveillance has been almost entirely restricted to China. More vigorous field research efforts tracking the circulation of Sarbecoviruses specifically and Betacoronaviruses more generally is needed across a broader global range if we are to avoid future repeats of the COVID-19 pandemic.

PCSK9 inhibition for LDL lowering and beyond – implications for patients with peripheral artery disease

VASA ◽  
2018 ◽  
Vol 47 (3) ◽  
pp. 165-176 ◽  
Author(s):  
Katrin Gebauer ◽  
Holger Reinecke
Keyword(s):  
Cardiovascular Risk ◽  
Risk Reduction ◽  
Ldl Receptor ◽  
Density Lipoprotein ◽  
Past Century ◽  
Pcsk9 Inhibitors ◽  
Cardiovascular Risk Reduction ◽  
Simultaneous Application ◽  
The Past ◽  
Pcsk9 Inhibition

Abstract. Low-density lipoprotein cholesterol (LDL-C) has been proven to be a causal factor of atherosclerosis and, along with other triggers like inflammation, the most frequent reason for peripheral arterial disease. Moreover, a linear correlation between LDL-C concentration and cardiovascular outcome in high-risk patients could be established during the past century. After the development of statins, numerous randomized trials have shown the superiority for LDL-C reduction and hence the decrease in cardiovascular outcomes including mortality. Over the past decades it became evident that more intense LDL-C lowering, by either the use of highly potent statin supplements or by additional cholesterol absorption inhibitor application, accounted for an even more profound cardiovascular risk reduction. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a serin protease with effect on the LDL receptor cycle leading to its degradation and therefore preventing continuing LDL-C clearance from the blood, is the target of a newly developed monoclonal antibody facilitating astounding LDL-C reduction far below to what has been set as target level by recent ESC/EAS guidelines in management of dyslipidaemias. Large randomized outcome trials including subjects with PAD so far have been able to prove significant and even more intense cardiovascular risk reduction via further LDL-C debasement on top of high-intensity statin medication. Another approach for LDL-C reduction is a silencing interfering RNA muting the translation of PCSK9 intracellularly. Moreover, PCSK9 concentrations are elevated in cells involved in plaque composition, so the potency of intracellular PCSK9 inhibition and therefore prevention or reversal of plaques may provide this mechanism of action on PCSK9 with additional beneficial effects on cells involved in plaque formation. Thus, simultaneous application of statins and PCSK9 inhibitors promise to reduce cardiovascular event burden by both LDL-C reduction and pleiotropic effects of both agents.

Archaeology in the Past Century

1901 ◽  
Vol 51 (1309supp) ◽  
pp. 20976-20977
Author(s):  
W. M. Flinders Petrje
Keyword(s):  
Past Century ◽  
The Past

A tes

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
IJE Manager
Keyword(s):  
Energy Supply ◽  
Fossil Fuels ◽  
Geographical Location ◽  
Weather Conditions ◽  
Past Century ◽  
Solar Pv ◽  
Pv Systems ◽  
Trade Offs ◽  
A Site ◽  
Selection Methodology

In the past century, fossil fuels have dominated energy supply in Indonesia. However, concerns over emissions are likely to change the future energy supply. As people become more conscious of environmental issues, alternatives for energy are sought to reduce the environmental impacts. These include renewable energy (RE) sources such as solar photovoltaic (PV) systems. However, most RE sources like solar PV are not available continuously since they depend on weather conditions, in addition to geographical location. Bali has a stable and long sunny day with 12 hours of daylight throughout the year and an average insolation of 5.3 kWh/m2 per day. This study looks at the potential for on-grid solar PV to decarbonize energy in Bali. A site selection methodology using GIS is applied to measure solar PV potential. Firstly, the study investigates the boundaries related to environmental acceptability and economic objectives for land use in Bali. Secondly, the potential of solar energy is estimated by defining the suitable areas, given the technical assumptions of solar PV. Finally, the study extends the analysis to calculate the reduction in emissions when the calculated potential is installed. Some technical factors, such as tilting solar, and intermittency throughout the day, are outside the scope of this study. Based on this model, Bali has an annual electricity potential for 32-53 TWh from solar PV using amorphous thin-film silicon as the cheapest option. This potential amount to three times the electricity supply for the island in 2024 which is estimated at 10 TWh. Bali has an excessive potential to support its own electricity demand with renewables, however, some limitations exist with some trade-offs to realize the idea. These results aim to build a developmental vision of solar PV systems in Bali based on available land and the region’s irradiation.

Catholicism and Cosmopolitanism: the Confluence of Three Catholic Scholars and the Cosmopolitan Democrats on State Sovereignty and the Future of Global Governance

2016 ◽  
Vol 3 (2) ◽  
pp. 37-51
Author(s):  
Matthew Bagot
Keyword(s):  
Global Governance ◽  
State Sovereignty ◽  
Current Debate ◽  
Past Century ◽  
Jacques Maritain ◽  
The Past ◽  
Technological Advances ◽  
The Future ◽  
Cosmopolitan Democracy ◽  
Catholic Tradition

One of the central questions in international relations today is how we should conceive of state sovereignty. The notion of sovereignty—’supreme authority within a territory’, as Daniel Philpott defines it—emerged after the Treaty of Westphalia in 1648 as a result of which the late medieval crisis of pluralism was settled. But recent changes in the international order, such as technological advances that have spurred globalization and the emerging norm of the Responsibility to Protect, have cast the notion of sovereignty into an unclear light. The purpose of this paper is to contribute to the current debate regarding sovereignty by exploring two schools of thought on the matter: first, three Catholic scholars from the past century—Luigi Sturzo, Jacques Maritain, and John Courtney Murray, S.J.—taken as representative of Catholic tradition; second, a number of contemporary political theorists of cosmopolitan democracy. The paper argues that there is a confluence between the Catholic thinkers and the cosmopolitan democrats regarding their understanding of state sovereignty and that, taken together, the two schools have much to contribute not only to our current understanding of sovereignty, but also to the future of global governance.

Aftershocks

2017 ◽  
Author(s):  
Seva Gunitsky
Keyword(s):  
Twentieth Century ◽  
Regime Change ◽  
International System ◽  
Political Legitimacy ◽  
Great Powers ◽  
Past Century ◽  
The Past ◽  
Sudden Rise ◽  
The World ◽  
National Borders

Over the past century, democracy spread around the world in turbulent bursts of change, sweeping across national borders in dramatic cascades of revolution and reform. This book offers a new global-oriented explanation for this wavelike spread and retreat—not only of democracy but also of its twentieth-century rivals, fascism, and communism. The book argues that waves of regime change are driven by the aftermath of cataclysmic disruptions to the international system. These hegemonic shocks, marked by the sudden rise and fall of great powers, have been essential and often-neglected drivers of domestic transformations. Though rare and fleeting, they not only repeatedly alter the global hierarchy of powerful states but also create unique and powerful opportunities for sweeping national reforms—by triggering military impositions, swiftly changing the incentives of domestic actors, or transforming the basis of political legitimacy itself. As a result, the evolution of modern regimes cannot be fully understood without examining the consequences of clashes between great powers, which repeatedly—and often unsuccessfully—sought to cajole, inspire, and intimidate other states into joining their camps.

Variable oil and argumentative conflict in the Middle East

2020 ◽  
pp. 824
Author(s):  
Malik Daham Mata’ab
Keyword(s):  
Middle East ◽  
Past Century ◽  
Large Area ◽  
The Past ◽  
The World

Oil has formed since its discovery so far one of the main causes of global conflict, has occupied this energy map a large area of conflict the world over the past century, and certainly this matter will continue for the next period in our century..

Mahmood Hasan Khan. Underdevelopment and Agrarian Structure in Pakistan. Boulder, Colorado: Westview Press. 1981. pp.xviii+ 307.

1981 ◽  
Vol 20 (4) ◽  
pp. 465-468 ◽  
Author(s):  
Douglas H. Perry
Keyword(s):  
Ownership Structure ◽  
Land Reform ◽  
Land Ownership ◽  
Past Century ◽  
The Past ◽  
Ownership Patterns ◽  
Agrarian Structure

Students of the land ownership patterns in Pakistan have always been hampered by extreme lack of data, neither the 1960 census nor the 1972 census reveal anything about the actual ownership structure of land. Khan's book goes some distance in providing numbers on land ownership (for 1971 and 1976), and also documents methods and failures of land reform efforts over the past century in Pakistan, disaggregated to show efforts in this regard in both the provinces of Sind and Punjab. The book actually provides an overwhelming amount of data - some 87 pages of charts and tables document a book of under 200 pages of text.

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