Electro-optic measurement of carrier mobility in an organic thin-film transistor

We have used an electro-optic technique to measure the position-dependent infrared absorption of holes injected into a thin crystal of the organic semiconductor, 6,13-bis(triisopropylsilylethynyl)-pentacene incorporated in a field-effect transistor. By applying square-wave voltages of variable frequency to the gate or drain, one can measure the time it takes for charges to accumulate on the surface, and therefore determine their mobility.Comment: 11 pages, 4 figures, to be published in Applied Physics Letter

Collapse of Kaluza-Klein Bubbles

Kaluza-Klein theory admits ``bubble" configurations, in which the circumference of the fifth dimension shrinks to zero on some compact surface. A three parameter family of such bubble initial data at a moment of time-symmetry (some including a magnetic field) has been found by Brill and Horowitz, generalizing the (zero-energy) ``Witten bubble" solution. Some of these data have negative total energy. We show here that all the negative energy bubble solutions start out expanding away from the moment of time symmetry, while the positive energy bubbles can start out either expanding or contracting. Thus it is unlikely that the negative energy bubbles would collapse and produce a naked singularity.Comment: 6 pages, plain LaTeX, UMDGR-94-08

Dynamics of Charge Flow in the Channel of a Thin-Film Field-Effect Transistor

The local conductivity in the channel of a thin-film field-effect transistor is proportional to the charge density induced by the local gate voltage. We show how this determines the frequency- and position-dependence of the charge induced in the channel for the case of "zero applied current": zero drain-source voltage with charge induced by a square-wave voltage applied to the gate, assuming constant mobility and negligible contact impedances. An approximate expression for the frequency dependence of the induced charge in the center of the channel can be conveniently used to determine the charge mobility. Fits of electro-optic measurements of the induced charge in organic transistors are used as examples.Comment: 9 pages including table + 3 figures; submitted to Jnl. Appl. Phy

Make Some Sense of Scent Trademarks: The United States Needs a Graphical Representation Requirement

When it comes to consumer loyalty, some businesses have decided to go beyond attracting the eyes. Why not keep customers via their nostrils? Accordingly, the scent marketing industry is booming. Jennifer Dublino, Vice President of Development at ScentWorld Events, remarks that “smell is one of the most unique of human senses. Scent enters the limbic system [of the brain] and bypasses all of the cognitive and logical thought processes and goes directly to the emotional and memory areas of the brain.” Companies like ScentAir have been created specifically to help stores design fragrances that best fit their image and objectives as a way to increase returns on investment. Science indicates that olfactory cues are more effective than visual cues at triggering memory. Scents\u27 strong ties to memory and emotions can make them a powerful branding tool. A study found that gamblers spent forty-five percent more money when there was a floral scent present around a slot machine than when there was not. Four hundred consumers, who were surveyed after shoppingin a Nike store, reported that a “pleasant ambient scent” improved not only their evaluation of the store and its products but the likelihood they would shop there again. Some human rights activists have even suggested that using scents to identify goods could be beneficial to those who are visually impaired and are not able to reap the benefits of visual trademarks. Overall, scents appear to both attract customers and increase their affinity to a particular good or service from a specific source, much like a mesmerizing logo or catchy slogan

In Love\u27s Bouquet

https://digitalcommons.library.umaine.edu/mmb-vp/3617/thumbnail.jp

A mother’s eternal role within the family unit

Despite there being extensive research on Early Parental Death (EPD), there has been no research to date that explores the lived experience of growing up following the loss of a mother during childbirth. This is not just a historical phenomenon, but something that still affects women today, with approximately eight-hundred and thirty passing away daily, from childbirth related complications, around the globe. All previous research in the field has been conducted in developing countries using a quantitative method. More qualitative research is needed so that practitioners in the field of Counselling Psychology can understand what the lived experiences is like for this group of individuals, to provide more tailored support. This study was conducted using semi-structured interviews with seven adult participants, and analysed using Interpretative Phenomenological Analysis (IPA). Three superordinate themes emerged from the data: ‘The isolation of not knowing where and how I fit’, which captures the ways in which participants described their relationships with other people and society, and at times the struggles that had with this. The second superordinate theme, ‘An indescribably emptiness that cannot be replaced’, presents an account of the different ways participants talked about what was missing in their life and their experience of managing this. Finally, the last superordinate theme, ‘Findings ways to manage’, captures the ways in which participants described both retrospective and current reflections on how they have overcome their early adversity. Both the findings and the limitations of the research are discussed, along with suggestions for future research

The isolation of gravitational instantons: Flat tori V flat R^4

The role of topology in the perturbative solution of the Euclidean Einstein equations about flat instantons is examined.Comment: 15 pages, ICN-UNAM 94-1

\u3cem\u3eRhizobium japonicum\u3c/em\u3e Mutants Defective in Symbiotic Nitrogen Fixation

Rhizobium japonicum strains 3I1b110 and 61A76 were mutagenized to obtain 25 independently derived mutants that produced soybean nodules defective in nitrogen fixation, as assayed by acetylene reduction. The proteins of both the bacterial and the plant portions of the nodules were analyzed by two-dimensional polyacrylamide gel electrophoresis. All of the mutants had lower-than-normal levels of the nitrogenase components, and all but four contained a prominent bacteroid protein not observed in wild-type bacteroids. Experiments with bacteria grown ex planta suggested that this protein was derepressed by the absence of ammonia. Nitrogenase component II of one mutant was altered in isoelectric point. The soluble plant fraction of the nodules of seven mutants had very low levels of heme, yet the nodules of five of these seven mutants contained the polypeptide of leghemoglobin. Thus, the synthesis of the globin may not be coupled to the content of available heme in soybean nodules. The nodules of the other two of these seven mutants lacked not only leghemoglobin but most of the other normal plant and bacteroid proteins. Ultrastructural examination of nodules formed by these two mutants indicated normal ramification of infection threads but suggested a problem in subsequent survival of the bacteria and their release from the infection threads