Liquid-immersible electrostatic ultrasonic transducer

A broadband megahertz range electrostatic acoustic transducer for use in a liquid environment is described. A liquid tight enclosure includes a metallic conducting membrane as part of its outside surface and has a means inside the liquid tight enclosure for applying a tension to the membrane and for mounting an electrode such that the flat end of the electrode is aproximately parallel to the membrane. The invention includes structure and a method for ensuring that the membrane and the flat end of the electrode are exactly parallel and a fixed predetermined distance from each other

The role of need for self-expression and arousal to commit university students for environmental responsibility behaviours

University social responsibility as recycling and environmental protection attitude is a core issue in higher education. However, scarce research examines the factors that influence individuals’ commitment to recycling and environmental preservation, and even less explores how that commitment can lead to preferential behavior, word of mouth and willingness to sacrifice for recycling and environmental preservation. This study examines the roles of need for self-expression and arousal to explain commitment and whether commitment leads to those behaviors. The study is duplicated in three countries, each representing different cultural dimensions. Data collected from participants at Universities in South Korea, the United States and Portugal inform a model that supports the majority of the hypotheses and points out some interesting differences in the ways that recycling and environmental preservation should be presented in various cultures to achieve buy-in and behavior change.info:eu-repo/semantics/acceptedVersio

Manufacture and Sale of Cultured Butter

Cultured butter, because of its pleasing and distinctive flavor, is finding new favor among consumers. Likewise, because of improved technology and an abundance of high quality raw materials readily available, it is now considered to be dependable butter and is winning new friends among butter dealers. The flavor in cultured butter is produced by adding from 1 to 3% of a milk culture of flavor producing bacteria directly to the butter during the working process. This gives a pleasing flavor to the butter which is maintained or increases slightly when the butter is held at household refrigerator temperatures for periods of 1 or 2 months. It is also maintained for at least 6 months when stored at 0°F. Consumers in Brookings and Sioux Falls showed a definite preference for butter with culture flavor over other butter and oleomargarine. Other consumer tests have given similar results. Butter quality in South Dakota has shown marked improvement since 1950. In that year a survey showed 81% of the butter was Grade B and 19% was Grade C. In 1959 the results of a similar survey were 22.3% Grade AA and A, 55.1% Grade B and 22.6% Grade C. Further improvement is possible and probable. The use of culture in more of Grades AA and A might result in increased demand for these grades of butter. Sales of this kind of butter have been increasing in this area

Hawaii energy strategy project 2: Fossil energy review. Task 3 -- Greenfield options: Prospects for LNG use

This paper begins with an overview of the Asia-Pacific LNG market, its major players, and the likely availability of LNG supplies in the region. The discussion then examines the possibilities for the economic supply of LNG to Hawaii, the potential Hawaiian market, and the viability of an LNG project on Oahu. This survey is far from a complete technical assessment or an actual engineering/feasibility study. The economics alone cannot justify LNG`s introduction. The debate may continue as to whether fuel diversification and environmental reasons can outweigh the higher costs. Several points are made. LNG is not a spot commodity. Switching to LNG in Hawaii would require a massive, long-term commitment and substantial investments. LNG supplies are growing very tight in the Asia-Pacific region. Some of the environmental benefits of LNG are not entirely relevant in Hawaii because Hawaii`s air quality is generally excellent. Any air quality benefits may be more than counterbalanced by the environmental hazards connected with large-scale coastal zone construction, and by the safety hazards of LNG carriers, pipelines, etc. Lastly, LNG is not suitable for all energy uses, and is likely to be entirely unsuitable for neighbor island energy needs

Hawaii energy strategy project 2: Fossil energy review. Task 1: World and regional fossil energy dynamics

This report in the Hawaii Energy Strategy Project examines world and regional fossil energy dynamics. The topics of the report include fossil energy characteristics, the world oil industry including reserves, production, consumption, exporters, importers, refining, products and their uses, history and trends in the global oil market and the Asia-Pacific market; world gas industry including reserves, production, consumption, exporters, importers, processing, gas-based products, international gas market and the emerging Asia-Pacific gas market; the world coal industry including reserves, classification and quality, utilization, transportation, pricing, world coal market, Asia-Pacific coal outlook, trends in Europe and the Americas; and environmental trends affecting fossil fuels. 132 figs., 46 tabs

A 160-Gb/s OTDM demultiplexer based on parametric wavelength exchange

Parametric wavelength exchange (PWE) has been demonstrated as a versatile device in providing different functionalities. In this paper, we will concentrate, numerically and experimentally, on one of these functionalities, namely, all-optical time demultiplexing of 160-Gb/s return-to-zero (RZ) signals based on a pulsed-pump PWE in a 400 m highly nonlinear dispersion-shifted fiber. Experimental results show power penalties < 2.7 dB at bit-error rate of 10-9 for all demultiplexed 10-Gb/s RZ signals. We also derive theoretical expressions for the conversion/residual efficiencies and investigate the impact of pump pulse width and phase mismatch on these efficiencies. Furthermore, the impacts of pulsed-pump wavelength and power level on the characteristics of the switching window are investigated numerically. As a result, the demultiplexer can be easily upgraded to an add-drop multiplexer because of the complete exchange nature of PWE, which is justified by the surviving channels' waveform performance. © 2009 IEEE.published_or_final_versio

Materials Characterization Using Acoustic Nonlinearity Parameters and Harmonic Generation: Effects of Crystalline and Amorphous Structures

The importance of nonlinearity in the description of material behavior is gaining widespread attention. Nonlinearity plays a major, if not dominating, role in a number of material properties. For example, properties that are important in engineering design such as thermal expansion or the pressure dependence of optical refraction are inherently nonlinear [1]. New assembley techniques such as the use of ultrasonic gauges to determine the loading of critical fasteners depend upon nonlinear properties of the fasteners [2]. Areas of considerable fundamental interest in nonlinearity include lattice dynamics [3], radiation stress in solids [4,5], and nonlinear optics [6

Tyrosine Phosphorylation of the UDP-Glucose Dehydrogenase of Escherichia coli Is at the Crossroads of Colanic Acid Synthesis and Polymyxin Resistance

BACKGROUND:In recent years, an idiosyncratic new class of bacterial enzymes, named BY-kinases, has been shown to catalyze protein-tyrosine phosphorylation. These enzymes share no structural and functional similarities with their eukaryotic counterparts and, to date, only few substrates of BY-kinases have been characterized. BY-kinases have been shown to participate in various physiological processes. Nevertheless, we are at a very early stage of defining their importance in the bacterial cell. In Escherichia coli, two BY-kinases, Wzc and Etk, have been characterized biochemically. Wzc has been shown to phosphorylate the UDP-glucose dehydrogenase Ugd in vitro. Not only is Ugd involved in the biosynthesis of extracellular polysaccharides, but also in the production of UDP-4-amino-4-deoxy-L-arabinose, a compound that renders E. coli resistant to cationic antimicrobial peptides. METHODOLOGY/PRINCIPAL FINDINGS:Here, we studied the role of Ugd phosphorylation. We first confirmed in vivo the phosphorylation of Ugd by Wzc and we demonstrated that Ugd is also phosphorylated by Etk, the other BY-kinase identified in E. coli. Tyrosine 71 (Tyr71) was characterized as the Ugd site phosphorylated by both Wzc and Etk. The regulatory role of Tyr71 phosphorylation on Ugd activity was then assessed and Tyr71 mutation was found to prevent Ugd activation by phosphorylation. Further, Ugd phosphorylation by Wzc or Etk was shown to serve distinct physiological purposes. Phosphorylation of Ugd by Wzc was found to participate in the regulation of the amount of the exopolysaccharide colanic acid, whereas Etk-mediated Ugd phosphorylation appeared to participate in the resistance of E. coli to the antibiotic polymyxin. CONCLUSIONS/SIGNIFICANCE:Ugd phosphorylation seems to be at the junction between two distinct biosynthetic pathways, illustrating the regulatory potential of tyrosine phosphorylation in bacterial physiology

Genetic Dissection of an Exogenously Induced Biofilm in Laboratory and Clinical Isolates of E. coli

Microbial biofilms are a dominant feature of many human infections. However, developing effective strategies for controlling biofilms requires an understanding of the underlying biology well beyond what currently exists. Using a novel strategy, we have induced formation of a robust biofilm in Escherichia coli by utilizing an exogenous source of poly-N-acetylglucosamine (PNAG) polymer, a major virulence factor of many pathogens. Through microarray profiling of competitive selections, carried out in both transposon insertion and over-expression libraries, we have revealed the genetic basis of PNAG-based biofilm formation. Our observations reveal the dominance of electrostatic interactions between PNAG and surface structures such as lipopolysaccharides. We show that regulatory modulation of these surface structures has significant impact on biofilm formation behavior of the cell. Furthermore, the majority of clinical isolates which produced PNAG also showed the capacity to respond to the exogenously produced version of the polymer

Expanding understanding of service exchange and value co-creation: A social construction approach

According to service-dominant logic (S-D logic), all providers are service providers, and service is the fundamental basis of exchange. Value is co-created with customers and assessed on the basis of value-in-context. However, the extensive literature on S-D logic could benefit from paying explicit attention to the fact that both service exchange and value co-creation are influenced by social forces. The aim of this study is to expand understanding of service exchange and value co-creation by complementing these central aspects of S-D logic with key concepts from social construction theories (social structures, social systems, roles, positions, interactions, and reproduction of social structures). The study develops and describes a new framework for understanding how the concepts of service exchange and value co-creation are affected by recognizing that they are embedded in social systems. The study contends that value should be understood as value-in-social-context and that value is a social construction. Value co-creation is shaped by social forces, is reproduced in social structures, and can be asymmetric for the actors involved. Service exchanges are dynamic, and actors learn and change their roles within dynamic service systems