Assaf, A.M., A. Hartman and N. Shalaby, Packing designs with block size 6 and index 5, Discrete Mathematics 103 (1992) 121-128. A (v, K, A) packing design of order v, block size K and index 1 is a collection of K-element subsets, called blocks, of a v-set V such that every 2-subset of V occurs in at most I blocks. The packing problem is to determine the maximum number of blocks in a packing des...

of Kirkman (first proven by Cayley; see [7]) for the number of dissections of an n-gon using d diagonals. The goal here is to generalize Bóna’s result to count 1-crossing partitions by their number of blocks, and also to examine a natural q-analogue with regard to the cyclic sieving phenomenon shown in [8] for certain q-Catalan and q-Narayana numbers. The crux is the observation that 1-crossing...

background: in radiation therapy, the sparing of normal tissues can be performed using either multi-leaf collimators or cerrobend blocks. the current work focuses on the physical characteristics of cerrobend blocks including attenuation coefficient, effective penumbra width and isodose curves undulation in penumbral regions. materials and methods: all measurements were performed using a dual en...

Diagnostic Procedures Nerve blocks are the most common type of invasive diagnostic procedure. Their rationale is simple: if a certain anatomical structure is the source of pain, then anesthetizing its nerve supply should temporarily relieve the pain. Face and construct validity have been demonstrated for blocks of the nerves that supply the zygapophysial (facet) joints of the cervical and lumba...

Further to the structure of intrinsic magnetic topological insulators $\mathrm{Mn}{\mathrm{Bi}}_{2}{\mathrm{Te}}_{4}\ifmmode\cdot\else\textperiodcentered\fi{}n({\mathrm{Bi}}_{2}{\mathrm{Te}}_{3})$ with $n<4$, where index $n$ is number quintuple Te-Bi-Te-Bi-Te building blocks inserted between neighboring septuple Te-Bi-Te-Mn-Te-Bi-Te blocks, members $n=4$, 5, and 6 was studied using x-ray pow...

Further to the structure of intrinsic magnetic topological insulators $\mathrm{Mn}{\mathrm{Bi}}_{2}{\mathrm{Te}}_{4}\ifmmode\cdot\else\textperiodcentered\fi{}n({\mathrm{Bi}}_{2}{\mathrm{Te}}_{3})$ with $n<4$, where index $n$ is number quintuple Te-Bi-Te-Bi-Te building blocks inserted between neighboring septuple Te-Bi-Te-Mn-Te-Bi-Te blocks, members $n=4$, 5, and 6 was studied using x-ray pow...

6-Fluoromevalonate blocks the incorporation of mevalonic acid, but not that of isopentenyl pyrophosphate, into non-saponifiable lipids in a rat liver multienzyme system. With 3H-labelled 6-fluoromevalonate, it was found that 6-fluoromevalonate is converted to its phospho and pyrophospho derivatives in this system. The kinetics of the two kinases were studied. 6-Fluoromevalonate 5-pyrophosphate ...

The objective of this study was to assess the influence of cortical thickness and bone density on the insertion torque of a mini-implant (MI) with microthreads. Mini-implants with lengths of 6 and 8 mm in the active part were inserted into synthetic bone blocks (polyurethane resin). The density of these blocks was 20 pounds per cubic foot (pcf), simulating bone marrow, and that of blocks 1, 2, ...