The Theory of Parity Violation in Few-Nucleon Systems

We review recent progress in the theoretical description of hadronic parity violation in few-nucleon systems. After introducing the different methods that have been used to study parity-violating observables we discuss the available calculations for reactions with up to five nucleons. Particular emphasis is put on effective field theory calculations where they exist, but earlier and complementary approaches are also presented. We hope this review will serve as a guide for those who wish to know what calculations are available and what further calculations need to be completed before we can claim to have a comprehensive picture of parity violation in few nucleon systems.Comment: 69 pages, 10 figures, accepted for publication in Prog. Part. Nucl. Phy

Automated Gain Control for Temporally Recursive Detail Reconstruction with Variable Video Input Sharpness

Modern video signal processing systems need to be highly adaptive in their processing configuration due to the broad range of input signal quality levels. In many cases the input quality is not known. In this paper, we report on our research on adaptivity to the sharpness level of the video content. Based on our work on temporally recursive detail reconstruction, which we presented in [1], we developed a system to measure the sharpness level in the input signal and for subsequent automatic gain control. Further we measure the current level of image enhancement and stabilizes it over time, approximating a predefined target enhancement level. Our proposed system helps to avoid over-enhancement of high quality input signals while adjusting the gain for low quality input signals in order to achieve an adequately enhanced output signal

Distressful Empathy in Reading Literature: The Case for Terror Management Theory?

This article will investigate the extent to which predictions of Terror Management Theory also hold on reading literature. Indeed, death is ubiquitous in fiction. But does reading about it cause the same reactions as those predicted by Terror Management Theory? To answer this question, five reading experiments were carried out. The hypothesis, developed in the framework of Terror Management Theory, that direct confrontation with one’s mortality strengthens both prejudices against outsiders and enhances in-group values, was tested. Contrary to initial expectations, the results did not confirm the predictions, casting a shadow over the hypothesis of distressful empathy. This raises the question whether mortality salience in literary texts is different from other such confrontations. This leads us to the question why people indulge in such distressful emotions. It will be argued that confrontation with death in literature may actually relieve the tension produced by mortality reminders. This perspective may be linked to Aristotle’s notion of catharsis.Статтю присвячено вивченню ступеня придатності висновків теорії керування страхом смерті до читання художнього тексту. Насправді, у літературі опис смерті є непоодиноким, але чи викликає читання про смерть ті ж самі реакції, про які постулюється у теорії керування страхом смерті? Щоб отримати відповідь на таке запитання авторами було проведення п’ять експериментів, у яких перевірялася гіпотеза, розроблена у межах теорії керування страхом смерті, про те, що безпосереднє зіткнення із смертністю підсилює упередженість по відношенню до чужинців і підвищує внутрішньогрупові цінності. На відміну від наших очікувань, результати експериментів не підтвердили таке припущення, і це ставить під сумнів гіпотезу про трагічну емпатію. Постає питання про те, чи відрізняється усвідомлення власної смертності, яке викликає художня література, від інших випадків зіткнення зі смертю, і це викликає запитання, чому читачі прагнуть зануритися у настільки трагічні емоції. Автори статті роблять припущення про те, що зіткнення зі смертю у художньому тексті може зменшити психологічне напруження, яке зазвичай викликають інші нагадування про смерть, і така перспектива може бути пов’язана із аристотелівським поняттям катарсису

Polystyrene-grafted Carbon Fibers: Surface Properties and Adhesion to Polystyrene

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.It is highly desirable to improve attractive interactions between carbon fibers and unreactive thermoplastic matrices to the possible maximum. This could be achieved by a simple grafting process to create a covalently bonded interface or interlayer, which should result in cohesive interactions between the polymer-grafted fibers and the same matrix material, leading to a better adhesion strength in the obtained composite material. Here, we are describing the grafting of styrene onto unmodified and unsized carbon fibers via free-radical bulk polymerization in the presence of fibers. After grafting, the surface properties of the carbon fiber approach those of pure polystyrene which was proven by contact angle and zeta (ζ) potential measurements. As indicated by the water contact angle, the carbon fiber surface becomes more hydrophobic. Scanning electron microscopy (SEM) provides evidence of grafted polymer. This simple procedure results in a continuous polystyrene coating. The fiber diameter increases significantly after polymer grafting. The adhesion and fracture behavior between the original and polystyrene-grafted carbon fibers to a polystyrene (VESTYRON®) matrix was characterized using the single-fiber pull-out test. There is a considerable increase in the measurable adhesion, i.e., the interfacial shear strength IFSS, by almost 300% between the grafted fibers and polystyrene as compared to untreated original fibers. Two planes of interfacial failure could be distinguished; first in the fiber coating interface leading to lower interfacial shear strength and second in the PS-matrix-PS-coating interphase resulting in a higher interfacial shear strength. In addition to the improved adhesion, there are also clear differences in the pull-out behavior between the nongrafted and grafted fibers. After the initial debonding process corresponding to the maximal pull-out force is completed, the pull-out force is increasing again