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Refrigerants used in various air conditioning and refrigeration industries are going through changes today and continued changes into the near future. These changes are being driven by environmental and energy efficiency regulations and could result in the use of refrigerants that require the investigation of new lubricants. One such change is the use of refrigerants that carry a lower global warming potential (GWP) value then current refrigerants used in the market. Some of these refrigerants present certain challenges over current refrigerants such as changes in flammability requirements, higher pressures or stability of the refrigerant in system operation. These refrigerants and the changes they represent may require different lubricants in order to maintain system optimization ensuring that energy efficiency and reliable requirements are met. The interaction between the refrigerant and the lubricant in any air conditioning or refrigeration system is a vital piece of information that is required to make certain optimal performance is achieved. The lubricant in a system is crucial to operation and needs to adequately lubricate the moving components in a system and return to the compressor when circulated. These conditions can drastically be affected by the refrigerant and lubricant interaction with improper choices resulting in consequences from lowering the overall performance to complete failure. This paper will look at some of the current and proposed low GWP refrigerants and their interaction with various lubricants. Evaluations will be made and certain properties will be presented that are essential to system operation. Of particular interest will be the refrigerant solubility factor of low GWP refrigerant candidates that can affect system performance and reliability; the stability of newer low GWP refrigerant candidates that maintain comparable current refrigerant system requirements; the miscibility of low GWP refrigerants with lubricants that can affect oil circulation; and how chemistry changes to various lubricants can help increase energy efficiency in systems operated with low GWP refrigerants. The information in this paper and the presentation will be a timely look at current and future needs for lubricants for various refrigerants that will help manufacturers in the air conditioning and refrigerant industry to evaluate the choices that need to be made in order to maintain the required system performance.

Conventional deterrence failed to prevent open warfare between Britain and Argentina over the Falkland Islands sovereignty issue. This thesis investigates the basic principles underlying conventional deterrence, and then applies those principles to the case study of the Falkland Islands conflict in order to discover why. This is accomplished by examining British political and military planning for the South Atlantic region from 1965--1982 for its ability to leverage effective deterrent threats against Argentina. Psychological factors concerning the rational actor model and their impact upon Britain's capacity to issue deterrent threats against Argentina are also discussed. These two factors are then used to analyze Britain's credibility and reputation in the South Atlantic Region and their effects upon Britain's deterrence posture. All these factors are then taken into account when analyzing the cost/benefit calculus of both Britain and Argentina. Thus, Britain's political and military planning, combined with severe psychological limitations, decreased its regional credibility and reputation, which severely undercut its ability to affect Argentina's cost/benefit analysis. This is why conventional deterrence failed in the Falkland Islands conflict. http://archive.org/details/conventionaldete109455357 US Army (USA) author Approved for public release; distribution is unlimited.

The familiar sight of flowers in a sunny meadow beset by a profusion of insect-visitors sharply contrasts with that of flowers inhabiting a quiet forest, apparently unvisited by flower-loving insects. Yet many plant species bear entomophilous flowers in deep shade beneath trees where there appears to be an extreme paucity of anthophilous insects. Several authors have commented upon the importance of sunlight to insect visits with the observation that shade inhibits many flower visitors (Perkins, 1919; Linsley, 1958; Free, 1960) while others will not penetrate the comparative gloom of the interior of a wood or forest (Kerner and Oliver, 1895). The presentation of entomophilous flowers by shade-loving species with such an apparently meagre chance of insect visits appeared anomalous, and worth investigation.

Samples of chasmogamous flowers of three species of Viola from seven different habitats were examined for the contents of their stigmatic cavities. Flower and pollen morphology are described. Insect exclusion experiments suggest that self-pollination is rare and emasculations have established that intraspecific and interspecific pollen transfer is frequent. The quantity of pollen introduced into the stigmatic cavity is affected by several factors. Rain reduces pollination in exposed habitats and similar decreases are detected in sheltered or north-or east-facing habitats due to the smaller amount of sunlight incident upon them. Percentage pollination remains high in habitats with no blossoms of other genera; anthophilous insects visit Viola for food. Habitats with a variety of blossoms besides Viola may lure sufficient insects to ensure the pollination of all species, including the inconspicuous ones. However, large stands of showy blossoms may monopolize the insect visitors in a habitat also occupied by less attractive species. It is argued that gene flow in disturbed or marginal habitats may be increased by the greater availability of potential pollinators.

The abundance of the familiar springtime flowers of Viola suggests that they are of great importance in the production of offspring. However, since the earliest days of pollination studies it has been recorded that insects seldom visited them and that the majority appeared to wither away unfertilized. The precise role of insects in the pollination of these flowers and their contribution to seed set was, therefore, extremely uncertain. The present paper reports part of a wider study which set out to establish whether or not violets were as neglected by insect-visitors as previously supposed. The frequency of visits appeared to be extremely critical for those violet species for which insect pollen vectors represent the only means of out-breeding.

Frasera speciosa is a conspicuous perennial in the Rocky Mountains where it forms discrete colonies whose inflorescences are characterized by almost total absence in some years and great abundance in others. This sporadic yet synchronous flowering was the most conspicuous feature of the reproductive biology of the species and its adaptive value was worth investigation. In a three-mile stretch of the East River valley, Colorado, the following data were gathered over a period of three years: the distribution and abundance of colonies, the floral biology, the dispersal of insect visitors among the flowers of Frasera and its floral associates, the frequency of floral predation and seed-set. Although the percentage of plants with inflorescences was always very low and despite the occasional wide spatial separation of individuals, Frasera invariably attracted the greatest number and diversity of floral visitors and never yielded less than 52% seed-set. It was also shown that pollination was effected by a wide variety of in sect visitors that maintained cross-pollination at a frequency of approximately 15%. In no colonies was floral predation nearly as heavy as in its sympatric associate Lupinus and it was concluded that seed-set in Frasera was not significantly affected by predispersal herbivory. The local synchrony revealed by the occurrence of discrete colonies and the overall synchrony revealed in the almost total absence of floral colonies in some years and their abundance in others is viewed as a strategy for predator avoidance. These mechanisms, together with other aspects of the reproductive biology, also reduce pressure from sympatric species competing for pollinators. It is pointed out that they confer reproductive advantage to a minority species which may otherwise rapidly decline to extinction in the presence of intense competition. The flowering regime of Frasera combines a predator avoidance system which yields widely dispersed colonies in space and in time with a pollination system which success-fully exploits the maximum diversity of floral visitors and maintains excellent seed-set whenever and wherever the colonies appear. The systems are clearly complementary in preventing the build-up of predator populations while maintaining an attractive forage source for potential pollen vectors. The combined effect is to maintain the abundance of the species in a variety of stress environments, in turn resulting in a remarkably wide geographic success. It is considered likely that similar systems will turn out to be very common among entomophilous plants in both temperate and tropical regions.

Fuchsin glycerine jelly provides a method of transforming insect or stigma-borne pollen into a semi-permanent mount in the field. All that is required is a container of jelly, a needle, microscope slides, cover slips and a spirit lamp and the preparations can be made very conveniently and very rapidly. For example, often the best method of identifying insect-borne pollen is to make a set of reference mounts while actually in the habitat under study.

A patient is described who has features of Pearson syndrome and who presented in the neonatal period with a hypoplastic anemia. He later developed hepatic, renal, and exocrine pancreatic dysfunction. At the age of 5 years he developed visual impairment, tremor, ataxia, proximal muscle weakness, external ophthalmoplegia, and a pigmentary retinopathy (Kearns-Sayre syndrome). Muscle biopsy confirmed the diagnosis of mitochondrial myopathy. Analysis of mtDNA from leukocytes and muscle showed mtDNA heteroplasmy in both tissues, with one population of mtDNA deleted by 4.9 kb. The deleted region was bridged by a 13-nucleotide sequence occurring as a direct repeat in normal mtDNA. Both Pearson syndrome and Kearns-Sayre syndrome have been noted to be associated with deletions of mtDNA; they have not previously been described in the same patient. These observations indicate that the two disorders have the same molecular basis; the different phenotypes are probably determined by the initial proportion of deleted mtDNAs and modified by selection against them in different tissues.

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