The effect of incomplete ionization on the turn-off behavior of FS IGBTs

This letter demonstrates for the first time the effect of the incomplete ionization (I.I.) of the transparent p-anode layer on the static and dynamic characteristics of the field-stop insulated gate bipolar transistors (FS IGBTs). This effect needs to be considered in FS IGBTs TCAD modeling to match accurately the device characteristics across a wide range of temperatures. The acceptor ionization energy (EA) governing the I.I. mechanism for the p-anode is extracted via matching the experimental turn-off waveforms and the static performance with Medici simulator. © 1980-2012 IEEE.

MEASUREMENT AND SIMULATION OF THE TURN-ON DELAY TIME JITTER IN GAIN-SWITCHED SEMICONDUCTOR-LASERS

The turn-on delay time jitter of four different unbiased gain-switched laser types is determined by measuring the temporal probability distribution of the leading edge of the emitted optical pulse. One single-mode 1.5-mu-m distributed feed-back laser and three multimode Fabry-Perot lasers emitting at 750 nm and 1.3-mu-m are investigated. The jitter is found to decrease for all lasers with increasing injection current. For multimode lasers it decreases from 8 ps excited slightly above threshold down to below 2 ps at three times the threshold current. The jitter of the distributed feedback (DFB) laser is a factor of 3-5 larger than the jitter of the three multimode lasers. A new model to predict the turn-on delay time jitter is presented and explains the experiments quantitatively.

Sensitive turn-on fluorescent detection of cyanide based on the dissolution of fluorophore functionalized gold nanoparticles

We report a simple fluorescent method for sensitive cyanide detection based on the dissolution of Rhodamine B-adsorbed gold nanoparticles by cyanide.

Turn-on fluorescent cyanide sensor based on copper ion-modified CdTe quantum dots

A new fluorescent sensor for the sensitive and selective detection of cyanide (CN-) in aqueous media was developed herein. The sensing approach is based on CN--modulated quenching behavior of Cu2+ toward the photoluminescence (PL) of CdTe quantum dots (QDs). In the presence of CN-, the PL of QDs that have been quenched by Cu2+ was found to be efficiently recovered, which then allows the detection of CN- in a very simple approach. Experimental results showed that the pH of the buffer solution, concentration of copper ions, and size of CdTe QDs all influenced the response of the sensor to CN-. Under the optimal conditions, a good linear relationship between the PL intensity and the concentration of CN- can be obtained in the range of 3.0 x 10(-7) to 1.2 x 10(-5) M, with a detection limit as low as 1.5 x 10(-7) M. In addition, the present fluorescent sensor possesses remarkable selectivity for cyanide over other anions, and negligible influences were observed on the cyanide detection by the coexistence of other anions or biological species (such as albumin and typical blood constituents).

Turn-on fluorescent detection of cyanide based on the inner filter effect of silver nanoparticles

A simple, sensitive fluorescent method for detecting cyanide has been developed based on the inner filter effect (IFE) of silver nanoparticles (Ag NPs). With a high extinction coefficient and tunable plasmon absorption feature, Ag NPs are expected to be a powerful absorber to tune the emission of the fluorophore in the IFE-based fluorescent assays. In the present work, we developed a turn-on fluorescent assay for cyanide based on the strong absorption of Ag NPs to both excitation and emission light of an isolated fluorescence indicator. In the presence of cyanide, the absorber Ag NPs will dissolve gradually, which then leads to recovery of the IFE-decreased emission of the fluorophore. The concentration of Ag NPs in the detection system was found to affect the fluorescence response toward cyanide greatly. Under the optimum conditions, the present IFE-based approach can detect cyanide ranging from 5.0 x 10 (7) to 6.0 x 10 (4) M with a detection limit of 2.5 x 10 (7) M, which is much lower than the corresponding absorbance-based approach and compares favorably with other reported fluorescent methods.

Angewandte Kulturwissenschaften – Überlegungen zum Studienprogramm einer akademischen Disziplin nach dem cultural turn im Hinblick auf berufliche Perspektiven

The author tries to attract attention for the careers ant the education of that what we call applied Cultural Studies after the cultural turn in the Humanities. He refers to some empirical studies and tries to put it out how differs the several institutes especially in the German spoken academic world. After all the conclusion of the author could be that there is an big demand for specialists in the area of applied cultural studies. The formation or education has to refer widely to a conception or the terminus of every-day-culture, so that it could be a big help in economic, social and education professions.

From the demise of theory to its resurgence. A retrospective on the postmodern turn to rethink the 'desire for narrative' and the sublime untimeliness of emancipation

Cultural Marxist Theory, commonly known as theory, enjoyed a moment of extraordinary success in the 1970s, when the works of leading post-war French philosophers were published in English. After relocating to Anglophone academia, however, theory disavowed its original concerns and lost its ambition to understand the world as a whole, becoming the play of heterogeneities associated with postcolonialism, multiculturalism and identity politics, commonly referred to as postmodern theory. This turn, which took place during a period that seemed to have spelt the death of Marxism, the 1990s, induced many of its supporters to engage in an ongoing funeral wake designating the merits of theory and dreaming its resurgence. According to them, had theory been resurrected in historical circumstances completely different from those which had led to its rise, it would have never reacquired the significance that had originally connoted it. This thesis demonstrates how theory has survived its demise and entirely regained its prominence in our socio-political context marked by the effects of the latest crisis of capitalism and by the global threat of terrorisms rooted in messianic eschatologies. In its current form theory does no longer need to show allegiance to certain intellectual stances or political groupings in order to produce important reformulations of the projects it once gave life to. Though less overtly radical and epistemologically bounded, theory remains a necessary form of enquiry justified by the political commitment which originated it in the first place. Its voice continues to speak to us about justice ‘where it is not yet, not yet there, where it is no longer’ (Derrida, 1993, XVIII).

Sonata Development at the Turn of the Century: From Liszt to Stravinsky

The sonata began to lose its position of predominance among compositions in the middle of the 19th century. Having been the platform for harmonic and thematic development of music since the late baroque period the sonata entered a process of reevaluation and experimentation with form. As a result fewer sonatas were being composed with some composers dropping the genre completely. This dissertation looks at the different approaches taken by the German, French and Russian schools of composition and compares the solo and chamber music applications of the sonata form. In the German tradition Franz Liszt's Sonata in b minor sets the standard for the revolutionary approach to form while the Berg Sonata is a very conservative application of form to an innovative use of extended chromaticism. Both composers chose to write one movement through composed pieces with Liszt working with a very expansive use of form and Berg being extremely compact and efficient. Among the Russian composers, Prokofieff's third sonata is also a one movement sonata, but he falls between Liszt and Berg in terms of the length of the piece and the use of innovative musical language. Scriabin uses a two movement approach, but keeps the element of a through composed piece with the same important material spanning both movements. Stravinsky is the most conservative of these with a three movement sonata that uses a mix of chromaticism and baroque and classical style influences. The French almost stopped composing true sonatas except for chamber music where Franck and Fauré write late romantic sonatas, while Debussy is very innovative within a three movement sonata. Estampes, by Debussy, are taken in almost as an afterthought to illustrate the direction Debussy takes in his piano solo music. While Estampes is by definition a set of character pieces they function like a sonata with three movements.

5-α reductase inhibitors and prostate cancer prevention: where do we turn now?

With the lifetime risk of being diagnosed with prostate cancer so great, an effective chemopreventive agent could have a profound impact on the lives of men. Despite decades of searching for such an agent, physicians still do not have an approved drug to offer their patients. In this article, we outline current strategies for preventing prostate cancer in general, with a focus on the 5-α-reductase inhibitors (5-ARIs) finasteride and dutasteride. We discuss the two landmark randomized, controlled trials of finasteride and dutasteride, highlighting the controversies stemming from the results, and address the issue of 5-ARI use, including reasons why providers may be hesitant to use these agents for chemoprevention. We further discuss the recent US Food and Drug Administration ruling against the proposed new indication for dutasteride and the change to the labeling of finasteride, both of which were intended to permit physicians to use the drugs for chemoprevention. Finally, we discuss future directions for 5-ARI research.

Computer modeling of a micro-manufactured one-turn inductor

The results of a finite element computer modelling analysis of a micro-manufactured one-turn magnetic inductor using the software package ANSYS 10.0 are presented. The inductor is designed for a DC-DC converter used in microelectronic devices. It consists of a copper conductor with a rectangular cross-section plated with an insulation layer and a layer of magnetic core. The analysis has focused on the effects of the frequency and the air gaps on the on the inductance values and the Joule losses in the core and conductor. It has been found that an inductor with small multiple air gaps has lower losses than an inductor with a single larger gap

We could make a meal out of nothing: contested explanations of inequalities in health

This paper reports on the qualitative findings from a comparative study of public health and lifestyles in South East England and Northern France, regions with similar geographic and economic characteristics. Data from health surveys showed that both countries had an increasing BMI with age, particularly in Northern France. This was despite the finding that the percentage eating fresh fruit and vegetable at least five days a week in Northern France increased with age (from well over 50% to over 90%) compared to around 50% to around 75% in South East England. Qualitative data on health inequalities and how they could be addressed were gathered by focus groups sampling from five tiers using the Townsend Index for comparability (14 in England with 106 participants overall; 13 in France with 143 participants). Both had about two thirds women participants, with a preponderance of middle aged and older people. There was a striking difference in the salience of diet between the two countries; in the French data it was raised only 14 times, whereas in England there were 165 occurrences, and these were often distinguished by their use of narrative. Older respondents contrasted the pressures on families today and the expense of fresh fruit and vegetables with their own childhood or childrearing, when cheap meals could be created using skills which have now been lost. These data therefore provide further evidence that providing food is a moral activity.