scholarly journals Solar irradiance and ENSO affect food security in Lake Tanganyika, a major African inland fishery

2020 ◽  
Vol 6 (41) ◽  
pp. eabb2191
Author(s):  
M. M. McGlue ◽  
S. J. Ivory ◽  
J. R. Stone ◽  
A. S. Cohen ◽  
T. M. Kamulali ◽  
...  
Keyword(s):  
Food Security ◽  
Solar Irradiance ◽  
High Frequency ◽  
Management Practices ◽  
Lake Tanganyika ◽  
Southern Oscillation ◽  
Frequency Changes ◽  
Warming World ◽  
Annual Resolution

Food security in a warming world is a grave concern for rapidly growing impoverished populations. Low-latitude inland fisheries provide protein for millions of rural poor, yet the impacts of high-frequency climate oscillations on these aquatic ecosystems are unknown. Here, we present a sub-annual–to–annual resolution paleolimnological reconstruction of upwelling, productivity, and algal composition at Lake Tanganyika, one of Africa’s largest landlocked fisheries. The data reveal increases in diatom production at centennial-scale solar irradiance maxima, and interannual variability in upwelling linked to La Niña. Our study shows that interactions between global climatic controls and El Niño–Southern Oscillation teleconnections exert profound influences on the foundation of Lake Tanganyika’s food web. Adapting long-term management practices to account for high-frequency changes in algal production will help safeguard inland fish resources.

scholarly journals EXPRESS: Measuring the real-time stock market impact of firm-generated content

2021 ◽  
pp. 002224292110428
Author(s):  
Ewelina Lacka ◽  
D. Eric Boyd ◽  
Gbenga Ibikunle ◽  
P.K. Kannan
Keyword(s):  
Subject Matter ◽  
High Frequency ◽  
Stock Price ◽  
Price Impact ◽  
Negative Valence ◽  
Price Impacts ◽  
Competitor Orientation ◽  
Frequency Changes ◽  
The Impact

Firms increasingly follow an ‘always on’ philosophy, producing multiple pieces of firm-generated content (FGC) throughout the day. Current methodologies used in marketing are unsuited to unbiasedly capturing the impact of FGC disseminated intermittently throughout the day in stock markets characterized by ultra-high frequency trading. They also neither distinguish between the permanent (i.e. long-term) and temporary (i.e. short-term) price impacts nor identify FGC attributes capable of generating these price impacts. In this study, the authors define price impact as the impact on the variance of stock price. Employing a market microstructure approach to exploit the variance of high frequency changes in stock price the authors estimate the permanent and temporary price impacts of the firm-generated Twitter content of S&P 500 IT firms. The authors find that firm-generated tweets induce both permanent and temporary price impacts, which are linked to tweet attributes; valence and subject matter. Tweets reflecting only valence or subject matter concerning consumer or competitor orientation result in temporary price impacts, while those embodying both attributes generate permanent price impact; negative valence tweets about competitors generate the largest permanent price impacts. Building on these findings, the authors offer suggestions to marketing managers on the design of intraday FGC.

scholarly journals Irrigated Agriculture in Malaysia and Vietnam: A Comparative Analysis of Water Governance Strategies

2020 ◽  
Vol 12 (1) ◽  
pp. 31-61
Author(s):  
Hanna Andrea Sand
Keyword(s):  
Water Management ◽  
Food Security ◽  
Management Practices ◽  
Water Governance ◽  
Irrigated Agriculture ◽  
Political Systems ◽  
Freshwater Resources ◽  
Governance Strategies ◽  
Insight Into

AbstractIrrigated agriculture has the potential to ensure food security, contribute to sustainable management, and preserve freshwater resources. At the same time, it is connected to problems such as water scarcity, environmental degradation and pollution, and poverty. This so-called “wicked” nature is addressed by comparatively analysing the strategies used for water governance in irrigated agriculture. To highlight its cross-sectoral nature, the concept of cross-sectoral alignment is introduced based on three governance criteria. The Southeast Asian countries of Malaysia and Vietnam are used to compare strategies as their differing political systems may lead to varying strategies and can thus offer greater insight into regional water management practices. The analysis suggests that the governance strategies used for irrigated agriculture have many similarities but also distinct differences. In particular, the influence of ODA in Vietnam as well as the way farmers are included in water management stand out in regards to the differences. Similar, however, are organisational set-ups, sectoral fragmentation, and insufficient supply of participatory mechanisms as well as generally low alignment across all categories. In consideration of the global importance of water management practices, only the aligned management of freshwater resources can increase environmental health and food security in the long term.

SEM image sharpness analysis

1996 ◽  
Vol 54 ◽  
pp. 142-143
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Quantitative Information ◽  
Primary Electron ◽  
Image Sharpness ◽  
Critical Dimensions ◽  
Sem Image ◽  
Frequency Changes ◽  
Electron Microscopes ◽  
Scanning Electron

Fully automated or semi-automated scanning electron microscopes (SEM) are now commonly used in semiconductor production and other forms of manufacturing. The industry requires that an automated instrument must be routinely capable of 5 nm resolution (or better) at 1.0 kV accelerating voltage for the measurement of nominal 0.25-0.35 micrometer semiconductor critical dimensions. Testing and proving that the instrument is performing at this level on a day-by-day basis is an industry need and concern which has been the object of a study at NIST and the fundamentals and results are discussed in this paper.In scanning electron microscopy, two of the most important instrument parameters are the size and shape of the primary electron beam and any image taken in a scanning electron microscope is the result of the sample and electron probe interaction. The low frequency changes in the video signal, collected from the sample, contains information about the larger features and the high frequency changes carry information of finer details. The sharper the image, the larger the number of high frequency components making up that image. Fast Fourier Transform (FFT) analysis of an SEM image can be employed to provide qualitiative and ultimately quantitative information regarding the SEM image quality.

GLOBAL FOOD SECURITY AMID THE GLOBAL CRISIS

2020 ◽  
Vol 1 (10) ◽  
pp. 134-141
Author(s):  
P. M. TARANOV ◽  
◽  
A. S. PANASYUK ◽  
Keyword(s):  
Food Security ◽  
Short Term ◽  
Global Food Security ◽  
Food Problem ◽  
Supply Problem ◽  
Coronavirus Infection ◽  
Food Security Indicators ◽  
Security Indicators ◽  
Global Food

The authors assess the prospects for solving the global food problem based on an analysis of the dynamics of food security indicators at the global and regional levels. The global food problem at work refers to the growing population of a planet affected by hunger and other forms of malnutrition. The food security situation has worsened for five years - in 2015–2019, and the COVID-19 pandemic has further exacerbated the food supply problem. The prevalence of moderate to severe food insecurity has affected more than 25% of the world's population. In lowincome countries, malnutrition affects more than 58% of the population. Food security is threatened by the consequences of the spread of coronavirus infection in the short term. In the medium and long term, climate change and the crisis in the governance of the world economy are the greatest threats. Modern international economic institutions are unable to withstand the prospect of declining global food security.

Monitoring Effects of Catchment Management Practices on Phosphorus Loads into the Eutrophic Peel-Harvey Estuary, Western Australia

1986 ◽  
Vol 18 (4-5) ◽  
pp. 53-61 ◽  
Author(s):  
P. B. Birch ◽  
G. G. Forbes ◽  
N. J. Schofield
Keyword(s):  
Management Practices ◽  
Major Change ◽  
High Flow ◽  
Catchment Management ◽  
Flow Rates ◽  
Early Results ◽  
Phosphorus Loads ◽  
Time Of Year ◽  
High Runoff

Early results from monitoring runoff suggest that the programme to reduce application of superphosphate to farmlands in surrounding catchments has been successful in reducing input of phosphorus to the eutrophic Peel-Harvey estuary. In the estuary this phosphorus fertilizes algae which grow in abundance and accumulate and pollute once clean beaches. The success of the programme has been judged from application of an empirical statistical model, which was derived from 6 years of data from the Harvey Estuary catchment prior to a major change in fertilizer practices in 1984. The model relates concentration of phosphorus with rate of flow and time of year. High phosphorus concentrations were associated with high flow rates and with flows early in the high runoff season (May-July). The model predicted that the distribution of flows in 1984 should have resulted in a flow-weighted concentration of phosphorus near the long-term average; the observed concentration was 25% below the long-term average. This means that the amount of phosphorus discharged into the Harvey Estuary could have been about 2 5% less than expected from the volume of runoff which occurred. However several more years of data are required to confirm this trend.

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