Handbuch der Oologie.

v.1:Lf.7(p.385-448

Handbuch der Oologie.

v.1:Lf.13(p.769-928

Handbuch der Oologie.

v.1:Lf.3(p.129-192

Handbuch der Oologie.

v.1:Lf.8(p.449-512

Handbuch der Oologie.

v.1:Lf.6(p.321-384

Handbuch der Oologie.

v.1:Lf.10(p.577-640

Diffractive Meson Production and the Quark-Pomeron Coupling

Diffractive meson production at HERA offers interesting possibilities to investigate diffractive processes and thus to learn something about the properties of the pomeron. The most succesful phenomenological description of the pomeron so far assumes it to couple like a $C = +1$ isoscalar photon to single quarks. This coupling leads, however, to problems for exclusive diffractive reactions. We propose a new phenomenological pomeron vertex, which leads to very good fits to the known data, but avoids the problems of the old vertex.Comment: 20 pages, latex with uuencoded postscript, revised versio

QCD sum rules with finite masses

The concept of QCD sum rules is extended to bound states composed of particles with finite mass such as scalar quarks or strange quarks. It turns out that mass corrections become important in this context. The number of relevant corrections is analyzed in a systematic discussion of the IR- and UV-divergencies, leading in general to a finite number of corrections. The results are demonstrated for a system of two massless quarks and two heavy scalar quarks.Comment: 15 pages, including two pictures to be found in an extra file. Latex neads epsf.st

MagiBricks: Fostering Intergenerational Connectedness in Distributed Play with Smart Toy Bricks

Playing together is crucial to the unique and invaluable bond between grandparents and grandchildren. However, co-located interactions and play can be limited due to time, distance, or pandemic-related restrictions. To facilitate distributed play, we developed MagiBricks, a system comprised of 3D-printed smart toy bricks and baseplates that provide feedback regarding their placement. The familiarity and appeal of toy bricks to both older adults and children make them ideal for intergenerational play. We conducted a within-subjects study with six grandparent-grandchildren pairs. We compared the interactions and perceived connectedness of the pairs while playing over a distance with either i) MagiBricks or ii) identical regular toy bricks. We found that MagiBricks affected communication dynamics, role taking, nature of play, and perception of connectedness during playtime compared to regular bricks, and were unanimously preferred. We contribute design implications for future systems leveraging (smart) tangibles and fostering intergenerational connectedness