Geometry of the valence transition induced surface reconstruction of Sm(0001).

We present a structural determination of the surface reconstruction of the Sm(0001) surface using surface x-ray diffraction, scanning tunneling microscopy, and ab initio calculations. The reconstruction is associated with a large (22%) expansion of the atomic radius for the top monolayer surface Sm atoms. The mechanism driving the surface reconstruction in Sm is unique among all elements and is connected to the strong correlations of the 4f electrons in Sm and the intermediate valence observed in certain Sm compounds. The atoms constituting the top monolayer of Sm(0001) have vastly different chemical properties compared to the layer underneath and behave as if they were an adsorbate of a different chemical species.

Strong phonon replicas in be 1s photoemission spectra.

The Be 1s core level photoemission line from metallic Be is shown to contain unexpected internal fine structure. We argue that this fine structure is caused by intrinsic excitation of a narrow band of optical phonons in the 1s photoemission process. The general importance of the present results for high resolution core level photoemission investigations of metals is pointed out.

Soft-x-ray polarimeter with multilayer optics: complete analysis of the polarization state of light.

The design of a versatile high-precision eight-axis ultrahigh-vacuum-compatible polarimeter is presented. This multipurpose instrument can be used as a self-calibrating polarization detector for linearly and circularly polarized UV and soft-x-ray light. It can also be used for the characterization of reflection or transmission properties (reflectometer) or polarizing and phase-retarding properties (ellipsometer) of any optical element. The polarization properties of Mo/Si, Cr/C, Cr/Sc, and Ni/Ti multilayers used in this polarimeter as polarizers in transmission and as analyzers in reflection have been investigated theoretically and experimentally. In the soft-x-ray range, close to the p edges of Sc, Ti, and Cr, resonantly enhanced phase retardation of the transmission polarizers of as much as 18 degrees has been measured. With these newly developed optical elements the complete polarization analysis of soft-x-ray synchrotron radiation can be extended to the water-window range from 300 to 600 eV.

Low- and standard-dose depot haloperidol combined with targeted oral neuroleptics.

Nine patients receiving a low dose (25 mg) and ten receiving a standard dose (150 mg) of depot haloperidol every four weeks were assessed every three months for two years. Patients also received targeted oral neuroleptics as needed. No significant between-group differences were found in clinical outcome as measured by number of hospital admissions, days hospitalized, scores on the Brief Psychiatric Rating Scale and the Global Assessment Scale, and level of extrapyramidal symptoms. Combining low-dose depot and targeted oral neuroleptics was at least as effective as using a standard depot dose and for many patients may provide the best way to reach the minimal effective dose for maintenance treatment.

Risperidone versus zuclopenthixol in the treatment of acute schizophrenic episodes: a double-blind parallel-group trial.

A double-blind, randomized, multi-center, parallel-group study was conducted in Finland to compare the efficacy and safety of risperidone with zuclopenthixol in patients with acute exacerbations of schizophrenia or schizophreniform disorder. Ninety-eight patients were randomly assigned to treatment with risperidone (n = 48) or zuclopenthixol (n = 50), in variable doses, for 6 weeks. The mean daily doses of risperidone and zuclopenthixol at the end of the trial were 8 mg and 38 mg respectively. Efficacy was assessed throughout by the Positive and Negative Syndrome Scale for schizophrenia and Clinical Global Impression. Safety assessments included the Extrapyramidal Symptom Rating Scale, UKU Side-Effect Rating Scale, vital signs, body weight and laboratory screening. The results indicate that risperidone is at least as effective as zuclopenthixol for the treatment of acute schizophrenic episodes, with a trend towards greater improvement in the overall severity of symptoms. The onset of action was significantly shorter with risperidone than with zuclopenthixol. Although the general tolerability of the two drugs was comparable, fewer patients experienced extrapyramidal symptoms with risperidone, so that significantly fewer risperidone-treated patients required antiparkinsonian medication.