Many different devices and cycle arrangements can be used in part.ially cooling gas for helium liquefaction . With the exception of the Simon freeexpansion type liquefier , howeverwhich is suitable only for small-yield, batch productionall uch arrangements have a final stage at the lowest temperatures, in which a so-called Joule-Thomson proces takes place. This process may be considered to incl...

In [18] Lorenz and Juhás raised the question of whether there exists a suitable formalism for the representation of infinite families of partial orders generated by Petri nets. Restricting ourselves to bounded p/t-nets, we propose Hasse diagram generators as an answer. We show that Hasse diagram generators are expressive enough to represent the partial order language of any bounded p/t net. We ...

Let G = (V ,E) be a simple connected graph and λ1(G) be the largest Laplacian eigenvalue of G. In this paper, we prove that: 1. λ1(G) = max{du +mu : u ∈ V } if and only if G is a regular bipartite or a semiregular bipartite graph, where du and mu denote the degree of u and the average of the degrees of the vertices adjacent to u, respectively. 2. λ1(G) = 2 + √ (r − 2)(s − 2) if and only if G is...

one of the major causes of spontaneous abortion before the fourth month of pregnancy is chromosomal abnormalities. we report an unusual case of a familial balanced chromosomal translocation in a consanguineous couple who experienced 4 spontaneous abortions. chromosomal studies were performed on the basis of g-banding technique at high resolution and revealed 46, xx, t (16 6) (p12 q26) and 46, x...

The issue of the number, nature and sequence of phase transitions in the fully frustrated XY (FFXY) model is a highly non trivial one due to the complex interplay between its continuous and discrete degrees of freedom. In this contribution we attack such a problem by means of a twisted conformal field theory (CFT) approach [1] and show how it gives rise to the U (1) ⊗ Z2 symmetry and to the who...

We develop a theory of transverse thermoelectric (Peltier) conductivity alpha(xy), in a strong magnetic field--this particular conductivity is often the most important contribution to the Nernst thermopower. We demonstrate that alpha(xy) of a free electron gas can be expressed purely and exactly as the entropy per carrier irrespective of temperature (which agrees with the seminal Hall bar resul...

We describe a case of XY sex reversal, gonadal dysgenesis, and gonadoblastoma in a patient with a deletion of 9p24 due to a familial translocation. The rearranged chromosome 9 was inherited from the father; the patient's karyotype was 46,XY,der(9)t(8;9) (p21;p24)pat. A review shows that 6 additional patients with 46,XY sex reversal associated with monosomy of the distal short arm of chromosome ...

Fluorescent in situ hybridization (FISH) with a 21q11-specific probe (CB21c1) consisting of three non-overlapping cosmids has been applied to interphase amniocytes of pregnancies at increased risk for fetal aneuploidy (N = 78) and to interphase lymphocytes, cultured and uncultured, of patients referred for Down syndrome (N = 19 and 28, respectively). In the uncultured amniocytes, six chromosome...

Heat-capacity measurements have been made on liquid-crystal compounds exhibiting almost no layer-shrinkage (NLS) behavior through the Sm-A-Sm- C(*) phase transition. The transition was found to be second order for two of the substances studied. It was found that the heat-capacity anomaly accompanying a second-order Sm-A-Sm- C(*) transition with NLS behavior is quite similar to that observed for...