The cycle of atmospheric nitrous oxide

1979 ◽  
Vol 290 (1376) ◽  
pp. 495-504 ◽  
Keyword(s):  
Laboratory Experiments ◽  
Nitrogen Fertilizers ◽  
Time Range ◽  
Microbial Activities ◽  
Electrical Discharges ◽  
Soil Systems ◽  
To Come ◽  
Turn Over ◽  
Over Time ◽  
Horizontal And Vertical Distribution

An attempt has been made to construct an N 2 O balance of the troposphere in order to demonstrate the state of knowledge of the cycle of atmospheric N 2 O. This balance has been constructed considering the parameters relevant for atmospheric N 2 O as far as known such as the horizontal and vertical distribution in the atmosphere and in the oceans, the variation of the atmospheric mixing ratio with time, the fluxes in the air-sea and in the air-soil systems, and man-made fluxes. The total atmospheric burden of N 2 O appears to be in the range 1600-2100 Mt, the tropospheric turn-over time between 4 and 12 years. Most of the atmospheric N 2 O seems to originate from microbial activities at the Earth’s surface with the oceans apparently being the major source with about 35 % of the total source as obtained from the tropospheric N 2 O mass and turn-over time (range of uncertainty 5-100 %) followed by soil and fresh water with about 25 % of the total source (range of uncertainty 4-100 %) including the contribution of industrial nitrogen fertilizers with about 10 % of the total source (range of uncertainty 2-24 %). Direct man-made N 2 O sources seem to be relatively small with about 2 % of the total source (range of uncertainty 0.5-5 %), but may grow considerably in the future. The N 2 O production by chemical reactions in the troposphere itself (e.g. electrical discharges) is not known; a figure of between 3 and 70 % of the total source has been inferred from laboratory experiments. The sinks of atmospheric N 2 O are poorly known. The only known major N 2 O destruction appears to occur in the stratosphere. The rate of transport into the stratosphere, however, limits this sink to about 10 % of the total amount of N 2 O to be destroyed under steady state conditions (range of uncertainty 3-22 %). The major problem of the cycle of atmospheric N 2 O is the unknown main sink. Since the stratosphere does not seem to come into question, the missing sink should be found somewhere in the troposphere, pedosphere, and/or hydrosphere.

Determination of the eddy turn-over time in the solar wind

2007 ◽  
Author(s):  
K. Bamert ◽  
R. Kallenbach ◽  
M. Hilchenbach ◽  
C. W. Smith
Keyword(s):  
Solar Wind ◽  
Turn Over ◽  
Over Time

scholarly journals Nitrogen fertilization in the contents of secondary compounds in cassava cultivars

2018 ◽  
Vol 39 (3) ◽  
pp. 1015 ◽  
Author(s):  
Diego Gazola ◽  
Claudemir Zucareli ◽  
Rudiney Ringenberg ◽  
José Perez da Graça ◽  
Clara Beatriz Hoffmann-Campo
Keyword(s):  
Nitrogen Fertilization ◽  
Acid Content ◽  
High Performance ◽  
Secondary Compounds ◽  
Nitrogen Fertilizers ◽  
Liquid Chromatograph ◽  
Cultural Management ◽  
Potted Plants ◽  
N Rates ◽  
Over Time

The production of chemical substances is a strategy of plants to defend against the attack of pest insects. The synthesis of secondary compounds in plants is influenced by genotype and cultural management, such as the use of nitrogen fertilizers. Thus, the objective of this work is to evaluate the effect of doses of nitrogen fertilizer over time on the production of secondary compounds in two industrial cassava cultivars. The experiment was carried out in a greenhouse (25 ± 5 °C) of Embrapa Soybean in Londrina, Paraná, with the cultivation of potted plants (4l) in a 2 × 4 × 3 factorial scheme, with five replications. Two genotypes of industrial cassava (‘Baianinha’ and ‘Caiuá’) and four different nitrogen doses (0, 30, 60, and 90 kg ha-1) were used, with sampling at 15, 30, and 45 d after fertilization. Nitrogen fertilization was performed 50 d after sprouting. In the apical leaves, the levels of rutin, caffeic, p-coumaric and ferulic acids were evaluated in a high performance liquid chromatograph (HPLC). Exploratory analyses were performed on the data variables to verify the assumptions for analysis of variance (ANOVA), such as the independence and normality of errors, homogeneity of treatment variances and non-additivity of the model (they were submitted to analysis of homogeneity and normality, respectively. After these tests, ANOVA and Tukey’s test (p ? 0.05) were performed. For the quantitative data concerning the N rates, regression study analyzes were performed. The Caiuá cultivar was found to have a higher ferulic acid content. The caffeic acid content decreased over time after the application of N in both cultivars. The rutin content in both cultivars did not increase with an increase in nitrogen dose. At a dose of 90 kg ha-1, both cultivars presented a lower p-coumaric acid content after 30 d.

scholarly journals Build me up to break me down: frothed spawn in the sandpaper frog, Lechriodus fletcheri, is formed by female parents and later broken down by their offspring

2019 ◽  
Vol 67 (3) ◽  
pp. 153
Author(s):  
John Gould
Keyword(s):  
Surface Area ◽  
Embryo Development ◽  
Direct Contact ◽  
Open Water ◽  
Air Bubbles ◽  
Temporal Shift ◽  
External Stresses ◽  
Resultant Increase ◽  
To Come ◽  
Over Time

Several genera of anuran amphibians deposit their eggs within mucous secretions that have been aerated by the parents to produce a foam or bubble spawn body. This is a dynamic medium for embryo development given that it gradually breaks down over time, and one that has been hypothesised to serve a variety of purposes including protecting embryos from external stresses, such as suboptimal temperatures, desiccation and predation. In this study, I provide additional details of bubble spawn production in the sandpaper frog, Lechriodus fletcheri. Field and laboratory observations showed that females aerate spawn while in inguinal amplexus, using flanged fingers to transport air bubbles into the mucous. While the frothed spawn is initially resistant to breakdown, it gradually loses bubbles and flattens out into a film. This temporal shift in structure is likely to be adaptive, as the resultant increase in surface area allows embryos to come in direct contact with the open water, which may accommodate their increased oxygen demands or ease extrication from the mass. I provide evidence that this process is controlled by the residing embryos, given that spawn in the absence of embryos does not break down, highlighting the ability of offspring to modify their immediate environment even before hatching occurs to ensure conditions remain suitable for their changing needs.

scholarly journals Designing Web Based Offering and Sales Information System (Case Study : PT. Daya Berkah Sentosa Nusantara)

2021 ◽  
Vol 1 (2) ◽  
Author(s):  
Siti Nurjanah Ramadhany ◽  
Ade Eviyanti
Keyword(s):  
Information System ◽  
Data Collection ◽  
Positive Impact ◽  
Literature Study ◽  
Web Based ◽  
Business World ◽  
The Public ◽  
To Come ◽  
Over Time

Technology is increasingly sophisticated with over time competition in the business world such as E-Commerce has a positive impact on entrepreneurs to advance their companies, namely by creating online websites so that offerings and sales are easy among the public. By accessing the website page of PT. Daya Berkah Sentosa Nusantara buyers do not have to come directly to the place or company, and send offers according to admin needs.The purpose of this study is to make it easier for researchers to solve supply and sales problems based on problems that arise in the company. The method used in this study is the Waterfall Method, with data collection techniques used using observation, interviews and literature study. The desired result of this research is to be able to create a website for the company, to be able to expand marketing reach, buyers can view products through the website.

scholarly journals XV. On the electricity of rain and its origin in thunderstroms

1909 ◽  
Vol 209 (441-458) ◽  
pp. 379-413 ◽  
Keyword(s):  
Rainy Season ◽  
Laboratory Experiments ◽  
Small Scale ◽  
Electrical Discharges ◽  
The Government ◽  
Satisfactory Manner

Since Franklin first showed that thunder and lightning are caused by electrical discharges, there have been numerous theories to account for the production of electricity in thunderstorms, but none has been generally accepted by meteorologists. When attacking the problems of thunderstorm electricity, two methods naturally present themselves: we may either investigate the actual phenomena in the atmosphere, or try to repeat on a small scale in the laboratory the processes which may be supposed to take place during thunderstorms. During 1907-8 an investigation was undertaken on both these lines at the Meteorological Office of the Government of India in Simla. A systematic record was obtained by automatic instruments of the electricity brought down by the rain during practically the whole of one rainy season, and laboratory experiments were made to find the origin of the electricity of thunderstorms. The work has resulted in the formation of a new theory, which appears to account in a satisfactory manner for the electrical effects observed during thunderstorms. The following paper is divided into three parts:—Part I deals with the measurements of the electricity of the rain, Part II with the laboratory experiments, and Part III contains the new theory based on the results detailed in the previous parts.

An evolutionary take on (im)politeness

2011 ◽  
Vol 12 (1-2) ◽  
pp. 255-282 ◽  
Author(s):  
Marcel Bax
Keyword(s):  
Sociocultural Factors ◽  
Interpersonal Distance ◽  
Rapport Management ◽  
To Come ◽  
Two Sides ◽  
Point Of Departure ◽  
Over Time ◽  
Broad Scale

This paper is intended as an overall template of the evolution of (im)politeness. It elucidates how (linguistic) rapport management originated and developed over time, and tries to come to grips with (some of) the sociocultural factors behind such changes. Taking its point of departure in human prehistory (Section 1), the paper argues that, contrary to received wisdom, politeness and impoliteness are not two sides of the same coin (Section 2), and it discusses the dissimilar evolutionary antecedents of politeness and impoliteness (Sections 3 and 4). The paper then maps out three broad-scale diachronic trends regarding the conveyance of interpersonal distance, ipso facto the marking out of socio-proxemic interactional space; namely, (a) from performative to verbal, (b) from self-display to other-concern and (c) from collectivity-oriented to individual-oriented (Section 5).

scholarly journals Social Class Origin and Assortative Mating in Britain, 1949–2010

Sociology ◽  
2017 ◽  
Vol 52 (6) ◽  
pp. 1217-1236 ◽  
Author(s):  
Ursula Henz ◽  
Colin Mills
Keyword(s):  
Social Class ◽  
Assortative Mating ◽  
Class Mobility ◽  
The Social ◽  
Class Origin ◽  
To Come ◽  
Similar Class ◽  
The 1960S ◽  
Level Aspect ◽  
Over Time

This article examines trends in assortative mating in Britain over the last 60 years. Assortative mating is the tendency for like to form a conjugal partnership with like. Our focus is on the association between the social class origins of the partners. The propensity towards assortative mating is taken as an index of the openness of society which we regard as a macro level aspect of social inequality. There is some evidence that the propensity for partners to come from similar class backgrounds declined during the 1960s. Thereafter, there was a period of 40 years of remarkable stability during which the propensity towards assortative mating fluctuated trendlessly within quite narrow limits. This picture of stability over time in social openness parallels the well-established facts about intergenerational social class mobility in Britain.

Welfare States in the Middle East and North Africa: Puzzles and Answers

2020 ◽  
pp. 1-51
Author(s):  
Ferdinand Eibl
Keyword(s):  
Political Economy ◽  
Analytical Framework ◽  
Welfare States ◽  
Theoretical Argument ◽  
Regime Formation ◽  
General Terms ◽  
To Come ◽  
The Moment ◽  
Over Time

Chapter 1 sets out the main empirical puzzles of the book, which are (i) the early divergence of welfare trajectories in the region and (ii) their long persistence over time. Drawing on literature from authoritarianism studies and political economy, it lays out the theoretical argument explaining this empirical pattern by developing a novel analytical framework focused on elite incentives at the moment of regime formation and geostrategic constraints limiting their abilities to provide welfare. It also outlines the author’s explanation for the persistence of social policies over time and broadly describes the three types of welfare regime in the region. It sbows the limitations of existing theories in explaining this divergence and bigbligbts the book’s contribution to the literature. The theoretical argument is stated in general terms and sbould thus be of relevance to political economy and authoritarianism scholars more broadly. The chapter ends with an outline of the chapters to come.

Getting Partisan

2020 ◽  
pp. 181-218
Author(s):  
Adam Slez
Keyword(s):  
Republican Party ◽  
Party Politics ◽  
Third Party ◽  
The Political ◽  
Political Field ◽  
People's Party ◽  
To Come ◽  
Over Time

This chapter traces the rise and fall of electoral Populism in southern Dakota. It begins by examining the transformation of the political field in Dakota Territory, where politics was traditionally organized around the fight for patronage. Excluded from power by the dominant faction of the Republican Party, the leaders of the Farmers’ Alliance turned to third-party politics as a means of waging war on their more elite rivals. I show that support for Populist candidates was closely with Alliance strength, though this relationship weakened over time as the People’s Party took on a life of its own. Major victories were hard to come by in the absence of electoral fusion. The free silver question served as a rallying point for pro-fusion forces, which succeeded in taking power. Unable to manage the distribution of patronage, the fusionist coalition quickly collapsed, taking what was left of the Populist movement with it.

scholarly journals A Toolkit for Evaluating Interventions to Improve Decision Making: The Garden Path Approach

2019 ◽  
Vol 8 (1) ◽  
pp. 130-134
Author(s):  
Simon Fernandez ◽  
Laura Militello ◽  
Christen Sushereba ◽  
David Bahner ◽  
Michael Barrie ◽  
...  
Keyword(s):  
Traffic Management ◽  
Nuclear Power ◽  
New Technologies ◽  
Air Traffic Management ◽  
Garden Path ◽  
Simulation Scenario ◽  
Asymmetric Learning ◽  
To Come ◽  
Measure Of Performance ◽  
Over Time

We propose a toolkit for objectively evaluating the effectiveness of new technologies for improving human cognitive performance. In complex socio-technical systems such as nuclear power generation and air traffic management, garden path scenarios have been effectively used to anchor initial inaccurate hypotheses that are then monitored for movement towards the correct hypotheses as increasing evidence over time makes it easier to change the diagnosis. The time to come to an accurate diagnosis in a well-crafted simulation scenario with an initial inaccurate anchor hypothesis is an objective, repeatable measure of performance for the macrocognition function of sensemaking. The time to verbalize the recognition of critical cues, which becomes increasingly less subtle over time, as well as the time to move from the inaccurate diagnosis at one of the correct diagnoses in the complete diagnostic set can all be reliably measured and compared in an across-subject study design. Modifications with conceptually matched scenarios using within-subject designs can also be employed if asymmetric learning effects are managed.

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