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The simulation of growth processes within soft biological tissues is of utmost importance for many applications in the medical sector. Within this contribution, we propose a new macroscopic approach for modelling stress-driven volumetric growth occurring in soft tissues. Instead of using the standard approach of a-priori defining the structure of the growth tensor, we postulate the existence of a general growth potential. Such a potential describes all eligible homeostatic stress states that can ultimately be reached as a result of the growth process. Making use of well-established methods from visco-plasticity, the evolution of the growth-related right Cauchy–Green tensor is subsequently defined as a time-dependent associative evolution law with respect to the introduced potential. This approach naturally leads to a formulation that is able to cover both, isotropic and anisotropic growth-related changes in geometry. It furthermore allows the model to flexibly adapt to changing boundary and loading conditions. Besides the theoretical development, we also describe the algorithmic implementation and furthermore compare the newly derived model with a standard formulation of isotropic growth. [ABSTRACT FROM AUTHOR]

The structure of the unbound proton-rich isotope 19Na was studied in resonance elastic scattering of a radioactive 18Ne beam on a proton target using the thick-target inverse-kinematics method. The experiment covered the excitation energy range from 0.5 to 2.7 MeV in c.m.s. Only one state of 19Na (the second excited state) was observed. A combined R-matrix and potential model analysis was performed. The spin and parity assignment of this second excited state was confirmed to be 1/2+. We show that the position of the 1/2+ state significantly affects the reaction rate through that state, but the total reaction rate remains unchanged since the 18Ne(2 p, γ) proceeds mostly via the ground and first excited states in 19Na at stellar temperatures. [ABSTRACT FROM AUTHOR]

Choroideremia is an X-linked hereditary retinal dystrophy leading to blindness in early adulthood. RFLP analyses in three Danish families were consistent with close linkage between choroideremia and the locus DXYS1, located at Xq13-Xq21. Measurable linkage was found between choroideremia and DXS17, at Xq22. Furthermore, choroideremia was diagnosed in a boy with an interstitial deletion at Xq13-Xq21, strongly suggesting the assignment of the locus for choroideremia to this region of the X chromosome. The deletion also covered DXYS1, but did not include DXS17. [ABSTRACT FROM AUTHOR]

Three families with at least three generations of family members affected with spino-cerebellar ataxia transmitted in a dominant fashion were studied. In each family every available member, above the lowest age at onset observed in that family, was subject to a thorough clinical investigation and blood was sampled for HLA,A,B and C-typing. In all three families the affected members had signs which were characteristic for cerebellar ataxia, without spasticity or dementia. In two families the mean age at onset was in accordance with the literature, viz. in the fourth and fifth decade, while in the third family mean age at onset was over 50 years. In the two pedigrees with the usual age at onset there was evidence of linkage between the disease and the HLA-system with a combined lod score of 1.499 at a recombination fraction of 0.05 for males. The third pedigree gave negative lod scores for linkage between HLA and the disease locus for both males and females but in this family also the high age at onset was indicative of genetic heterogeneity. [ABSTRACT FROM AUTHOR]

Genetic markers controlled by 21 genetic systems were studied in 13 families containing members suffering from various hereditary disorders involving ataxia. Classical cerebellar ataxia was present in four, Friedreich ataxia in two, hereditary spastic paraplegia in four, and the Charcot-Marie-Tooth syndrome in three families. In each family, every available member above the lowest age at onset observed in that family, was subjected to a thorough clinical investigation and blood was sampled for investigation of genetic markers. The families with cerebellar ataxia and with Charcot-Marie-Tooth syndrome contained enough informative relatives to allow a formal linkage study using the lodscore method. Three of the pedigress with cerebellar ataxia gave evidence of linkage between the disease and the HLA system with a combined lodscore of 2.128 at a recombination fraction θ of 0.05 for both sexes combined. The recombination fraction was considerably higher in females than in males, although the difference between the two sexes was not statistically significant. Negative lodscores were obtained for the remaining family with cerebellar ataxia, which might be due to the fact that this family only provided information on recombination in females. However, the clinical features in this family differed from those in the other three families by a significantly higher frequency of dementia and pyramidal tract lesions. Based on these observations and on contradictory results in the literature concerning linkage between cerebellar ataxia and HLA, we suggest that there are two forms of cerebellar ataxia: One (CA) linked to HLA with symptoms restricted to lesions in the cerebellum and spinocerebellar system and another (CA) not linked to HLA with symptoms from more wide-spread lesions of the CNS. None of the other genetic markers (except perhaps GLO) showed linkage to the cerebellar ataxias. Negative lodscores throughout with all 21 genetic markers were found in the families with Charcot-Marie-Tooth syndrome. There was no evidence for linkage between HLA on the one hand and Friedreich ataxia or hereditary spastic paraplegia on the other. [ABSTRACT FROM AUTHOR]

A C4 variant found in about 5% of the population is described. The fast-moving part of this variant is governed by an allele ( F) codominant to F. The F allele is in very strong linkage disequilibrium with HLA-B17 as the linkage disequilibrium parameter accounted for nearly 100% of the haplotype frequency of B17, F. The strong association is also evidenced by the study of 11 families segregating for the F allele. There was no instance of recombination between C4 and HLA in 36 informative meioses. [ABSTRACT FROM AUTHOR]

The association between DNA insertion sequences located near the insulin gene and the dominantly inherited maturity-onset diabetes of young people was studied in a large family. The distribution of the restriction fragments was compatible with Mendelian segregation. However, no linkage was found between the DNA insertion sequences and this form of diabetes. [ABSTRACT FROM AUTHOR]

Studies with 20 different genetic marker systems were performed in a large kindred including 18 members affected with maturity onset type of diabetes of young people. Linkage closer than 0.1⩽θ could be excluded for ABO and Gm, and linkage closer than 0.05⩽θ for HLA GLO, and haptoglobin. No significant positive lod scores were found. [ABSTRACT FROM AUTHOR]

We present a new approach for the measurement of resonance excitation functions of neutron-rich nuclei using Doppler shift information. Preliminary data from the first application of the method is presented in the spectroscopy studies of 7He isobaric analog states in 7Li. [ABSTRACT FROM AUTHOR]

TheAl(He,α)Al reaction has been used to determine 1-transfers for states inAl between 6.3- and 6.5- MeV excitation. Angular distributions of α-particles between 5° and 15°, when added to our previously published results confirm a strong 1=0 component for a state at 6363 keV but indicate pure 1=2 for states at 6410 and 6498 keV. We discuss implications for nucleosynthesis. [ABSTRACT FROM AUTHOR]

The excitation energies of states inNa near the proton threshold have been measured with theNe(He, t)Na charge exchange reaction. The possible implications of these states for the stellar reaction rate ofNe(p,γ) Na are discussed. [ABSTRACT FROM AUTHOR]