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Substitution of the bromine ligands in [(n-Bu)₄N]₂[Mo₃S₇Br₆] (1) by bidentate ligands such as maleonitriledithiolate (mnt) or oxalate (ox) affords the trinuclear clusters [Mo₃S₇(mnt)₃]2− ([2]2−) and [Mo₃S₇(ox)₃]2− ([3]2−) in moderate yields. The structures of clusters [2]2− and [3]2− have been determined by single-crystal X-ray diffraction as their tetrabutylammonium salts. Cluster 2 forms dimers by interaction of one sulfur atom of the mnt ligand with the anionic binding site of the cluster anion. The structure of 3 reveals the presence of aggregates between the anionic cluster and a Br− ion. The ESI-MS indicate that these cluster–bromine adducts are also present in solution. Electrochemical studies on complexes 1–3 show two irreversible waves associated with reductive cleavage of the disulfido bridges and one or two quasi-reversible oxidation processes for [Mo₃S₇(ox)₃]2− or [Mo₃S₇(mnt)₃]2−, respectively. No oxidation waves have been observed for compound 1 or for its thiocyanate derivative [(n-Bu)₄N]₂[Mo₃S₇(SCN)₆] (4) within the acetonitrile solvent window. The optical limiting properties of the complexes 1–4 have been measured by the Z-scan technique employing 40 ns pulses at 523 nm. Power limiting was observed for clusters 1, 2 and 4, whereas the oxalate derivative 3 was photochemically unstable under our experimental conditions.

Substitution of the bromine ligands in n-Bu4N2Mo3S7Br61 by bidentate ligands such as maleonitriledithiolate mnt or oxalate (ox) affords the trinuclear clusters Mo3S7mnt32−22− and Mo3S7ox32−32− in moderate yields. The structures of clusters 22−and 32−have been determined by single-crystal X-ray diffraction as their tetrabutylammonium salts. Cluster 2forms dimers by interaction of one sulfur atom of the mnt ligand with the anionic binding site of the cluster anion. The structure of 3reveals the presence of aggregates between the anionic cluster and a Br−ion. The ESI-MS indicate that these cluster–bromine adducts are also present in solution. Electrochemical studies on complexes 1–3show two irreversible waves associated with reductive cleavage of the disulfido bridges and one or two quasi-reversible oxidation processes for Mo3S7ox32−or Mo3S7mnt32−, respectively. No oxidation waves have been observed for compound 1or for its thiocyanate derivative n-Bu4N2Mo3S7SCN64 within the acetonitrile solvent window. The optical limiting properties of the complexes 1–4have been measured by the Z-scan technique employing 40 ns pulses at 523 nm. Power limiting was observed for clusters 1, 2and 4, whereas the oxalate derivative 3was photochemically unstable under our experimental conditions.

1. The stereoisomers of delta-(alpha-aminoadipyl)-L-cysteinylvaline (LLD, LLL and DLD) were synthesized from valine labelled with 3H in its methyl groups or in the alpha position. L-Cysteinyl-D-[4,4′-3H]valine was also synthesized. 2. 3H was incorporated into a compound that behaved like penicillin N when the LLD tripeptide containing either a methyl- or an alpha-labelled valine residue was incubated with a cell-free system prepared by lysis of protoplasts of Cephalosporium acremonium. 3. Incorporation was not observed under these conditions from the labelled all-L- or DLD-tripeptide, from L-cysteinyl-D-[4,4′-3H]valine, or of Penicillium chrysogenum appeared to be the LLD isomer, like that from C. acremonium. 5. These findings are discussed in relation to penicillin biosynthesis.

1. 3H was incorporated into solvent-soluble penicillin from isopenicillin N and 6-aminopenicillanic acid 3H-labelled in the 2β-methyl group when the labelled compounds were incubated with a crude extract of Penicillum chrysogenum. 2. With a soluble protein fraction of the extract incorporation from isopenicillin N occurred on addition of phenyl-acetyl-CoA. 3. Labelled benzylpenicillin was isolated after incubation of the crude extract with phenylacetyl-CoA and isopenicillin and the addition of unlabelled benzylpenicillin as a carrier. 4. No incorporation of 3H into solvent-soluble penicillin was detected on incubation of these extracts with penicillin N.

1. Phenoxymethylpenicillin sulphoxide 4-methoxybenzyl ester was labelled with 3H in its 2-β-methyl group. Its specific radioactivity was 362 mCi/mmol. 2. Removal of the side chain of this compound yielded the corresponding ester of 6-aminopenicillanic acid sulphoxide and coupling of the latter with the appropriate protected α-aminoadipic acid gave 4-methoxybenzyloxycarbonylisopenicillin N sulphoxide di-4-methoxybenzyl ester or the corresponding derivative of penicillin N. 3. Removal of the protective groups by hydrogenolysis and reduction of the sulphoxide group yielded 3H-labelled isopenicillin N or penicillin N. 4. 3H-labelled phenoxymethylpenicillin sulphoxide was obtained by hydrogenolysis from its 4-methoxybenzyl ester. Reduction of its sulphoxide group and subsequent removal of the side chain gave 3H-labelled 6-aminopenicillanic acid.

This paper presents a model for the nursing management of the effects of neuroleptic or antipsychotic medication. The model addresses the contemporary issues facing nurses, their clients and families, while at the same time is congruent with the continua of effects of these medications. For many, nonadherence is directly related to undesired side effects, while for others the reasons may be multidimensional. The proposed model addresses the notion of advocacy and empowerment in the light of interventions that relate to the undesired‐desired effects continuum. Underpinning this is the notion of the phases of the nurse‐client relationship, which were advocated by Peplau (1952) and have since offered a framework for nursing intervention. While developing the phases of this relationship, nurses can help the client and family by assuming various roles that can enhance the relationship. It is suggested that each of these roles has an element of advocacy and an element of empowerment. It is part of the nurses' professional responsibility to help the client and their family to deal with the issues surrounding medication nonadherence.

Interest in the subject of the present study was stimulated on reading Mackay's1 report on nutritional anemia in infancy. The conclusions reached in that report, if confirmed, would demand that all children during the first year or two of life receive a fairly large daily supplement of iron.The literature on anemia in infancy has been adequately covered in the aforementioned report, and only additional pertinent contributions will be referred to here. The most intriguing of recent publications are those dealing with the possibility that copper may play a significant rôle in the synthesis of hemoglobin. The results of the experiments of Elvehjem and Hart2 on animals to the effect that, whereas impure inorganic salts of iron cured nutritional anemia, the pure salts failed to do so, unless supplemented by small amounts of copper, have already been applied by clinicians to the treatment of anemia. The most carefully

GEOMAGNETIC micro-pulsations are considered to provide indirect evidence of the existence of hydromagnetic waves generated at the magnetosphere boundary and propagated towards the Earth as Alfvén waves. Dungey1and Jacobs and Westphal2have made predictions, based on theoretical studies, regarding the dependence of the period of these waves on latitude and on their state of polarization. There is, however, no general agreement among observers that this dependence on latitude does exist. Not enough work has been done as yet on the polarization of these waves to warrant a comparison between theory and observation.

The cases included in this series represent the total number of cases of infantile tetany treated in the Children's Hospital of Philadelphia during 1924 and the first nine months of 1925. These cases were studied at the instigation and under the direction of Dr. J. P. C. Griffith, to whom we are indebted for the privilege of reporting them. The cases have been studied from the aspects of etiology, symptomatology, blood studies and treatment.ETIOLOGIC FACTORSEighteen of the infants were colored; three were white, of whom one was Italian, and two of Anglo-Saxon parentage.Twelve infants, or 57.1 per cent, were males; nine, or 42.9 per cent, were females. That is, there were four males to every three females.The age at which symptoms began was noted. From table 1, it will be seen that no cases began after the fourteenth month, and that eleven cases, or 52.4 per

IN common with most solids, rocks usually suffer a constant Q type of absorption (Knopoff and MacDonald, 1958). That is to say, in each cycle of harmonic vibration a certain proportion of the maximum strain energy is converted into heat, and this proportion is independent of the period of vibration. In addition, and this is important in seismology, it appears that the elastic moduli of rocks also are practically independent of frequency.

Conventional seismometers employ masses of several kilogrammes suspended with periods of several seconds, but it is possible to achieve the same detection capability with much smaller masses suspended at shorter periods. Such instruments are valuable for borehole applications or where many instruments must be rapidly set up. The problems of the design of miniature wideband force-feedback seismometers are discussed and two such instruments are described. Both instruments use a capacitive displacement transducer to detect the relative motion of a mass of about 0.05 kg suspended with a natural period near 1 s. A force-feedback system maintains the mass stationary with respect to the instrument frame and the instruments have a response defined by feedback from Dc to 10 Hz. A single miniature instrument can thus provide data over the whole of the seismic range. Details are given of the experimental difficulties encountered and of a comparison of the instruments with conventional seismometers.

Seismometers for measuring horizontal vibrations respond not only to the required ground motion but also to unwanted tilts, caused by atmospheric or local effects. Because of the equivalence of inertial and gravitational accelerations, it is not possible to separate these effects in a single instrument. However, absolute rotation is detectable and an angular accelerometer has been developed, responding only to tilt and not to either horizontal or vertical ground motion. The design of the instrument is very similar to that of a modern horizontalcomponent seismometer, comprising a double balanced pendulum pivoted at its centre of gravity and operated in a force feedback configuration. Details of the design, testing and cabibration are presented. The instrument was operated in a seismic vault for several weeks, together with standard borehole and surface-mounted seismometers. The outputs were digitized and recorded, and the results analysed off-line on a pc using a data analysis package. Recordings obtained under different conditions of wind and seismic activity are presented and attempts made to reduce the effects of tilt on the surface recordings by subtracting the signal from the angular accelerometer after suitable processing. The tilt signal proved to be rather low, except on very windy days, so that complete correction for tilt was not possible. Suggestions are made for improving the instrument to make it useful in seismic vaults.

Rubidium magnetometers were set up at the three United Kingdom observatories and simultaneous recordings of micropulsations occurring in the total field direction were obtained for the second half of 1964. An analysis of these records is described which brings out the general features of micropulsations and which indicates some differences between occurrences at the three stations. A latitude dependence of period is displayed, and the occurrence time of Pc is shown to be distinctly different at Lerwick and Hartland. It is indicated that harmonic components occur in the wave trains, but they do not appear in the general analysis reported here.

A SELF-OSCILLATING rubidium vapour magnetometer, in which measurements of the total field magnitude are obtained by counting the frequency of self-oscillation in the radio-frequency range, has been developed for rocket and satellite experiments. Field trials have recently demonstrated that this lype of rubidium magnetometercan be used in certain observatory applications and other ground investigations of the geomagnetic field.