scholarly journals A LIST OF CALIFORNIA APHIDIDÆ

1903 ◽  
Vol 35 (9) ◽  
pp. 247-254 ◽  
Author(s):  
Warren. T. Clarke
Keyword(s):  
Economic Importance ◽  
The Past ◽  
Systematic List

Our knowledge of the group Aphididæ in California has been limited in the past to certain forms that were of economic importance in their relations to cultivated crops. No systematic list of these interesting insects has heretofore been attempted in this region, and this has not been due to any lack of material, for the varying conditions of climate here seem to be particularly favorable to them.

scholarly journals The effect of an outbreak of the leaf miner Micrurapteryx salicifoliella on the performance of multiple Salix species in interior Alaska

Botany ◽  
2018 ◽  
Vol 96 (8) ◽  
pp. 491-497 ◽  
Author(s):  
Diane Wagner ◽  
Patricia Doak
Keyword(s):  
Stem Elongation ◽  
Leaf Tissue ◽  
Economic Importance ◽  
Leaf Miner ◽  
Leaf Water Content ◽  
Leaf Blotch ◽  
The Past ◽  
Interior Alaska ◽  
Leaf Mining ◽  
General Decline

The genus Salix L. tends to be tolerant of herbivory, but severe outbreaks of herbivorous insects may compromise growth. First documented in Alaska in 1991, the willow leaf blotch miner, Micrurapteryx salicifoliella, is now responsible for frequent and widespread foliar damage to Salix in interior Alaska. We experimentally tested the effect of leaf mining on the performance of four susceptible Salix species across two years of outbreak, and placed the results in the context of a broader survey of leaf mining damage. Across the four species, reduction of leaf mining damage increased average stem elongation, numbers of leaves per shoot, and leaf area. Leaf mining damage was negatively related to leaf water content; a consequence of the leaf miner’s habit of breaching the cuticle on the underside of leaves. Growth deficits due to leaf mining are likely caused by both the loss of leaf tissue to leaf miner feeding and subsequent leaf desiccation. The results are notable in the context of a general decline in productivity in interior Alaska over the past few decades and because the leaf miner impacts Salix species also used by vertebrate browsers of cultural and economic importance, such as moose.

scholarly journals Andalusian Organic Farming Plans (2002–2016): Themes, Approaches and Values

2021 ◽  
Vol 13 (6) ◽  
pp. 3570
Author(s):  
José-Francisco Jiménez-Díaz ◽  
Francisco Collado-Campaña
Keyword(s):  
Content Analysis ◽  
Organic Farming ◽  
Semantic Content ◽  
Economic Importance ◽  
Ecological Agriculture ◽  
Political Values ◽  
The Past ◽  
Analysis Methodology ◽  
Semantic Fields ◽  
Spanish Region

Organic farming in the Spanish region of Andalusia has acquired great socio-economic importance over the past decades. The purpose of this article is to study the themes, approaches, and socio-political values pertaining to ecological agriculture addressed in the Andalusian plans for organic farming (2002–2016). The contents of these plans have not been systematically studied before. From a descriptive and qualitative perspective, the authors present and classify the main themes addressed in those plans and show the socio-political approaches and values that underpin the plans. A thematic and semantic content analysis methodology is applied to the plans and sections addressing various objectives, measures, and actions. A theoretical-qualitative sampling is developed, and 109 keywords are selected for content analysis. This analysis allows us to detect numerous themes pertaining to ecological agriculture and to classify them into six semantic fields linked to various approaches and values promoted by the Andalusian autonomous administration. Therefore, this research focuses on changing perspectives of organic farming developed by the administration and the agents involved in the plans. The authors conclude that the diverse actors have prioritized a productivist–technocratic approach to ecological agriculture, to the detriment of an approach centered on sustainable and agroecological local communities.

The Future Of Master Limited Partnerships

2014 ◽  
Vol 30 (5) ◽  
pp. 1492
Author(s):  
Charles F. Beauchamp
Keyword(s):  
Institutional Investors ◽  
Economic Importance ◽  
Low Risk ◽  
The Past ◽  
Size Number ◽  
The Future ◽  
New Entrants ◽  
Investment Portfolios ◽  
Limited Partnerships ◽  
Business Structure

<p>Master limited partnerships have grown in size, number, and economic importance over the past fifteen years. They now represent a stable and healthy component of many investment portfolios. MLPs have generated impressive risk-adjusted performance compared to that of other equity investments. This performance is the result of their fee-based, low risk business structure that produces a steady cash distribution to investors. The future to these traditional MLPs and similar new entrants is quite positive. However, new entrants that potentially deviate from this successful operating structure are entering the MLP market. This raises major questions regarding the sustainability of these firms as MLPs. This study examines the future of MLP markets within the context of traditional and non-traditional new entrants. Furthermore, the emergence of institutional investors on MLP markets is discussed.</p>

scholarly journals Global economic value of shark ecotourism: implications for conservation

Oryx ◽  
2013 ◽  
Vol 47 (3) ◽  
pp. 381-388 ◽  
Author(s):  
Andrés M. Cisneros-Montemayor ◽  
Michele Barnes-Mauthe ◽  
Dalal Al-Abdulrazzak ◽  
Estrella Navarro-Holm ◽  
U. Rashid Sumaila
Keyword(s):  
Analytical Approach ◽  
Economic Value ◽  
Economic Benefits ◽  
Economic Importance ◽  
The Past ◽  
The World ◽  
Shark Conservation ◽  
Shark Fisheries

AbstractAmid declining shark populations because of overfishing, a burgeoning shark watching industry, already well established in some locations, generates benefits from shark protection. We compile reported economic benefits at shark watching locations and use a meta-analytical approach to estimate benefits at sites without available data. Results suggest that, globally, c. 590,000 shark watchers expend > USD 314 million per year, directly supporting 10,000 jobs. By comparison, the landed value of global shark fisheries is currently c. USD 630 million and has been in decline for most of the past decade. Based on current observed trends, numbers of shark watchers could more than double within the next 20 years, generating > USD 780 million in tourist expenditures around the world. This supports optimistic projections at new sites, including those in an increasing number of shark sanctuaries established primarily for shark conservation and enacted in recognition of the ecological and economic importance of living sharks.

United States Foreign Policy in Southern Africa: Third-World Perspectives

1983 ◽  
Vol 21 (4) ◽  
pp. 587-603 ◽  
Author(s):  
Davidson Nicol
Keyword(s):  
United States ◽  
Human Rights ◽  
Reagan Administration ◽  
Third World ◽  
The United States ◽  
Economic Importance ◽  
United States Foreign Policy ◽  
Multilateral Aid ◽  
The Past ◽  
The Government

The past decade has seen an increase in the scope of relationships, both political and economic, between Africa and the United States. These vary with the complexion of the government in power, though some would say that this was more in emphasis than in substance, others definitely not. It is felt by many Africans, nevertheless, that the Carter Administration's emphasis on human rights has now been downgraded by the present Reagan Administration and that, instead, the geopolitics of U.S.–U.S.S.R. rivalry, and the economic importance of developing the private sector at the expense of bilateral or multilateral aid, have been moved to the fore.

Storage and shelf life

1975 ◽  
Vol 191 (1102) ◽  
pp. 185-191 ◽  
Keyword(s):  
Life Expectancy ◽  
Shelf Life ◽  
Food Industry ◽  
Physical Factor ◽  
Storage Conditions ◽  
Economic Importance ◽  
Waste Prevention ◽  
The Past ◽  
Food Technologist ◽  
World Economic

These apparently mundane and pedestrian topics have grown in world economic importance recently, and such currently fashionable words and phrases as conservation, total world supplies, waste prevention, must now be involved under these headings. Good storage conditions are probably more involved with temperature than any other single physical factor. The correct temperature can lie anywhere between -40 and +40 °C, depending on the food and ‘life’ expectancy. In the past, the food industry did not always give proper priority to the provision of good storage facilities. This attitude has latterly changed as the community and the industry have become aware of the benefits. Shelf life is the activity by which the food technologist ensures that the product reaches the consumer in the best possible condition. It is properly determined by experiment, taking into account conditions of storage, transport, packaging, microbiological and biochemical deterioration. Shelf-life information must be communicated to distributor, retailer and consumer in a meaningful and uncomplicated manner. The next decade will see greater effort and expenditure put into understanding and exploiting the better storage and freshness of food to the advantage of the community.

scholarly journals I.—The Iron-fields of Lorraine

1918 ◽  
Vol 5 (11) ◽  
pp. 481-483
Author(s):  
R. H. Rastall
Keyword(s):  
Iron Ore ◽  
Economic Importance ◽  
Industrial Nation ◽  
The Past ◽  
Grand Total

Recent events have again called attention to the enormous strategic and economic importance of the iron-fields of Lorraine; on these much of the commercial prosperity of Germany has been built up in the past, and on their possession her future as an industrial nation largely depends. For many years the output of iron-ore from tlie part of Lorraine under German control has been immense: in 1912, German Lorraine produced approximately 20,000,000 tons, while the output of Luxemburg, which, for all practical purposes, is German, was about 6,500,000 tons. In the same year the French portion of the Lorraine iron-field yielded 17,300,000 tons, making a grand total for this area of 43,800,000 tons of ore. During the War the whole of the French productive region has been occupied by the enemy, and there is no means of ascertaining what has actually happened there, but certain inferences can be drawn from published facts and on a basis of probability.

scholarly journals Risk Identification and Evaluation of the Long-term Supply of Manganese Mines in China Based on the VW-BGR Method

2019 ◽  
Vol 11 (9) ◽  
pp. 2683 ◽  
Author(s):  
Shule Li ◽  
Jingjing Yan ◽  
Qiuming Pei ◽  
Jinghua Sha ◽  
Siyu Mou ◽  
...  
Keyword(s):  
Supply And Demand ◽  
Impurity Content ◽  
Economic Importance ◽  
Low Grade ◽  
Manganese Ore ◽  
Supply Risk ◽  
The Past ◽  
Production Ratio ◽  
Equilibrium Market

Manganese is mostly used in the iron and steel industry and serves as an important metal mineral in the national economy. It is difficult to substantially increase the output of China’s manganese ore because it is of low grade and high impurity content. However, as a large consumer in the world, it is very important to ensure the long-term stable supply of this mineral. Collecting historical data on manganese ore in China over the past 20 years, we identified and evaluated risks during the whole process of production, supply, consumption, reserves, and trade of resources using the Volkswagen and German Federal Institute for Geosciences and Natural Resources (VW-BGR) method by selecting nine indicators: current market equilibrium, market price volatility, Reserve/production ratio, import dependence, import concentration, country risks, country concentration and future supply and demand trend. Furthermore, we assessed its economic importance by calculating the contribution of manganese ore involved in different value chains. It shows the same downward trend both in manganese ore consumption and economic importance, and the future demand of manganese ore will slow down, and the global supply will exceed demand. Based on the comprehensive evaluation of supply and demand trends in the past and future, it was concluded that the current market balance, import dependence and country concentration risks are the main driving factors for the supply risk of manganese ore in China, showing higher supply risk than that of the other factors; the resource and geostrategic risks are moderate, and may significantly reduce the supply risk if effective measures are implemented. As per the aforementioned analysis, to address the risk of supply interruption, this study provides some suggestions and measures, such as strengthening resource reserves and low-grade manganese ore utilization at home, actively exploring foreign markets, exploiting overseas resources, expanding import channels, extending the industrial chain, and adopting equity mergers and acquisitions abroad.

Engineering Problems Associated with the Improvement of Temperature and Humidity Conditions of the Atmosphere in Mines at Great Depths

1938 ◽  
Vol 139 (1) ◽  
pp. 185-235
Author(s):  
J. H. Dobson ◽  
W. J. Walker
Keyword(s):  
Large Scale ◽  
Final Section ◽  
Economic Importance ◽  
Compressed Air ◽  
The Past ◽  
Great Economic Importance ◽  
Engineering Problems ◽  
Temperature And Humidity ◽  
The Subject ◽  
Cooling Media

The subject is very complex and a great deal of research has been devoted to it on account of its great economic importance. The magnitude of the problems involved is shown by reviewing underground conditions on the Witwatersrand goldfields. Consideration of the limiting air conditions underground enables a specified mine-cooling problem to be enunciated. The final section of the paper reviews the various methods that have been tried for cooling the air in deep mines; some have been wholly or partially given up and some have survived. In particular, the possibilities of meeting requirements on a large scale have been analysed. Reference is made to cooling schemes which have been inaugurated on the Witwatersrand goldfields during the past two or three years. An analysis sets forth the relative merits of water, brine, and air as media for cooling deep mines, and a comparison of cooling plant performances and costs is made on the basis of: (1) vapour refrigerating plants on the surface and underground, using air and water respectively as cooling media, and (2) compressed air refrigeration.

The nutrition of the bacon pig. I. The influence of high levels of protein intake on growth, conformation and quality in the bacon pig

1936 ◽  
Vol 26 (4) ◽  
pp. 546-619 ◽  
Author(s):  
H. E. Woodman ◽  
R. E. Evans ◽  
E. H. Callow ◽  
J. Wishart
Keyword(s):  
Protein Intake ◽  
Live Weight ◽  
Economic Importance ◽  
Substantial Part ◽  
Carcass Quality ◽  
Food Conversion ◽  
Nutritional Factors ◽  
Experimental Animals ◽  
The Past ◽  
Swine Nutrition

The present practice of basing payment for bacon pigs not merely on carcass weight, but also on carcass quality as expressed in the factory grading results, has led necessarily to an enlargement of outook on the part of the investigator in the domain of swine nutrition. The interest of the experimenter in the past has tended to be restricted to such questions as the influence of nutritional factors on the rate of live-weight increase and the efficiency of food conversion, the problem of how feeding may influence carcass quality and conformation not having received the attention its importance merited.While the questions of the rate of growth and the efficiency, in terms of meal consumption, with which such growth is achieved are still matters of primary economic importance, it is realized that much more attention must be devoted than heretofore to the study of carcass quality and conformation in relation to feeding. In present circumstances, a nutritional investigation can scarcely be considered complete unless a substantial part of the research is carried out in the bacon factory following the slaughter of the experimental animals.

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