González, Flores, and Ortega Reply: Yeom argues in the preceding Comment [1] that the dynamical fluctuations scenario for the In=Si111-4 1 $ 8 2 transition is in apparent contradiction with the available photoemission data: (a) The high-resolution angle-resolved photoemission (ARP) data exhibit no sign of an extra broadening at RT in the bands near Fermi level; (b) the In 4d core-level spectra are apparently broader at low temperature (LT) than at RT.Regarding point (a), our high temperature simulations show that the broadening of the peaks at T 450 K due to the atomic motion is less than 80 meV [see Fig. 1] suggesting that at RT it should be of the order of 50 -60 meV. The broadening found in the experimental ARP data [2,3] is of the order of 100-200 meV, both at LT and RT, implying that it is dominated by the experimental resolution. We also comment that the insulating-(4 2) and the metallic-(4 1) bands are different only in the region close to the Fermi level [4]; in this energy region, the metallic state (although not a majority state) is the only one contributing to the spectra, in agreement with the experimental evidence.Regarding point (b), we argue here that the LT (4 2) structure and the atomic motion described in our Letter [5] offer a simple explanation for the In 4d core-level data. At RT, the In 4d core-level spectra present two components ( and ) [2]; although the deconvolution of the In 4d core level at LT is not unique [6], the data at LT seem to show that the RT component splits into 1 and 2 with a splitting of 0.2 eV, while the component is not changed. This behavior can be explained as follows. At LT, one can associate the component with the outer atoms of the In row and the two components with the inner In atoms (in the LT structure [5], all the outer In atoms are basically equivalent, while there are two distinct inner In atoms). At RT, a soft shear mode [5] introduces important displacements of the inner In atoms; thus, we can expect the two LT peaks to merge into a single broader peak, as shown in the RT data. Thus, although the LT data seem to be broader than the RT one, in fact it is the contrary because the 1 and 2 peaks appear as a single peak at RT due to the fluctuations described by our model.In conclusion, the dynamical fluctuations model for the In=Si111-4 1 $ 8 2 phase transition is completely consistent with the available photoemission results. Moreover, this model offers a good explanation (see Ref.[5]) for the observed new structures [semimetallic (4 1) and individual (4 2) chains] appearing at intermediate temperatures [7]. The appearance of these structures shows that this transition cannot be described simply as a displacive transition between well-defined RT and LT structures. The dynamical fluctuations presented in our Letter are a step beyond that simplified description, showing how the interrelation between electronic and structural properties in this system gives rise to the complex atomic dynamics that lie at the heart of this phase transition.We thank Professor E. G. ...

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Familial hypercholesterolaemia (FH) is an autosomal dominant disease characterized by elevated levels of low-density lipoprotein-cholesterol (LDL-C). Phenotypic expression is highly variable, being influenced by diet, age, gender, body mass index, apolipoprotein E genotype and type of LDL-receptor gene mutation. Microsomal triglyceride (TG) transfer protein (MTP) is a protein involved in lipid metabolism. Polymorphism MTP -493 GT has been shown to modulate lipid levels in several populations. To analyse the effect of this polymorphism in the lipid phenotype expression of FH and treatment response, we studied a sample of 222 Spanish FH patients, of whom 147 were studied before and after treatment with 20 mg of atorvastatin daily during 6 weeks. The variant was analysed by polymerase chain reaction amplification and single-strand confirmation polymorphism. Treatment reduced LDL-C, total cholesterol and TGs. Baseline fasting TGs and very-low-density lipoprotein cholesterol levels were lower in female T allele carriers (TG: 111+/-51 mg/dl GG, 89+/-35 mg/dl GT, 83+/-26 mg/dl TT, P=0.022; very-low-density lipoprotein cholesterol: 24+/-13 mg/dl GG, 16+/-5 mg/dl GT, 17+/-5 mg/dl TT, P=0.018). Triglyceride response to atorvastatin was modulated by this polymorphism in men (P=0.009), but not in women, although differences between genotypes were maintained after treatment. In conclusion, the MTP -493 GT polymorphism modulates pre- and post-treatment plasma TG values of FH in Spanish subjects in a gender-specific way. Other environmental and genetic factors likely also modulate this response.