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OBJECTIVE: The objective of the trial was to determine the efficacy of the proven anticalculus active system (zinc citrate trihydrate [ZCT] and triclosan), when the ZCT is delivered from microgranules incorporated in a silica-based toothpaste containing 1450 ppm F as sodium fluoride. DESIGN: A monadic, single-blind, two phase design clinical trial was used to compare the effect of the test and a negative control fluoridated toothpaste on the formation of supragingival calculus. SUBJECTS AND METHODS: Male and female calculus-forming volunteers, aged 18 or over, were recruited for the study following a 2-week screening phase. All subjects were given a scale and polish of their eight lower anterior teeth at the start of both the pre-test and test phases. Subjects were supplied with a silica-based 1450 F ppm fluoridated toothpaste with no anti-calculus active for use during an 8-week pre-test phase. Calculus was assessed at the end of the pre-test and test phases using the Volpe-Manhold index (VMI). Subjects were stratified according to their pre-test VMI score (8–10, 10.5–12, > 12) and gender and then allocated at random to test or negative control toothpaste groups. Subjects with < 8 mm of calculus were excluded from further participation. MAIN OUTCOME MEASURE: The outcome variable was the mean VMI score for the test and negative control groups. RESULTS: The test toothpaste caused a statistically significant 30% reduction in calculus compared with the control paste after a 13-week use. No adverse events were reported during the study. CONCLUSION: The incorporation of the ZCT in microgranules did not adversely affect the anticalculus activity of the new formulation.

Measurements of 63Ni (t12 = 100 yr) produced by the reaction 63Cu(n,p)63Ni could be used in the assessment of fast-neutron fluence from the Hiroshima atomic bomb. Such measurements would add new information to help resolve the current discrepancy between measured thermal neutron activation values and those calculated with the DS86 dosimetry system. It has been estimated that the 63Ni production at 5 m from the hypocenter was (1.4 ± 0.1) × 107 atoms/g Cu. Because of its sensitivity, accelerator mass spectrometry (AMS) is ideal for measurements at this low level. However, 63Ni has to be separated from large amounts of stable atomic isobar 63Cu (69% of pure Cu). In this study, a procedure is presented for the electrochemical separation of ultra-low amounts of Ni from Cu. The method was developed using samples of electrical Cu wire that were irradiated with fission neutrons from a 252Cf source. The wire samples were electrochemically dissolved in a solution containing 1 mg of Ni carrier. The Cu was selectively deposited on a cathode at controlled potential. Measurements of total Ni after electroseparation indicate ∼ 100% carrier recovery. To prevent Cu contamination, AMS targets were prepared by nickel carbonyl generation. The AMS results show a successful quantitative separation of ∼ 107 atoms of 63Ni from 2–20 g samples of Cu.

Let Ω be a set,Ra ring of characteristicp>0, and denote byMktheR-module withk-element subsets of Ω as basis. Theset inclusion map∂: Mk→Mk−1is the homomorphism which associates to ak-element subset Δ the sum ∂(Δ)=Γ1+Γ2+···+Γkof all its (k−1)-element subsets Γi. In this paper we study the chain[formula]arising from ∂. We introduce the notion ofp-exactness for a sequence. If Ω is infinite we show that (∗) isp-exact for all prime characteristicsp>0. This result can be extended to various submodules and quotient modules, and we give general constructions arising from permutation groups with a finitary section. Two particular applications are the following: The orbit module sequence of such a permutation group on Ω isp-exact for every primep, and we give a formula for thep-rank of the orbit inclusion matrix if the group has finitely many orbits onk-element subsets.

Interest in electrical energy storage systems is increasing as the opportunities for their application become more compelling in an industry with a back-drop of ageing assets, increasing distributed generation and a desire to transform networks into Smart Grids. A field trial of an energy storage system designed and built by ABB is taking place on a section of 11 kV distribution network operated by EDF Energy Networks in Great Britain. This paper reports on the findings from simulation software developed at Durham University that evaluates the benefits brought by operating an energy storage system in response to multiple events on multiple networks. The tool manages the allocation of a finite energy resource to achieve the most beneficial shared operation across two adjacent areas of distribution network. Simulations account for the key energy storage system parameters of capacity and power rating. Results for events requiring voltage control and power flow management show how the choice of operating strategy influences the benefits achieved. The wider implications of these results are discussed to provide an assessment of the role of electrical energy storage systems in future Smart Grids.

The purpose of this study was to identify factors which predispose to aseptic loosening of the femoral component in cemented total hip replacement. Its design was based on rigid selection criteria, so that successful and loose replacements which employed the same surgical technique were compared. Measurements of patient anatomy and of the insertion of the femoral component were made, by an accurate computer technique, on initial post-operative radiographs. Loosening was associated with heavier patients with a wider medullary canal which was flared proximally. This difference in anatomy led to differing distributions of cement in the successful and loose replacements. Medial cement-bone demarcation, at the mid-stem level, was also associated with loosening. These findings indicate the importance of optimizing the size of the prosthesis with respect to the femoral morphology.

Many primary schools conventionally organise more active mental work in the morning on the assumption that children learn better at that time of day. Some secondary schools are changing to starting...

A computer method was used to make 41 measurements on the geometry of insertion of the femoral component in 200 Charnley total hip replacements. Surgery had been performed at least 12 years before, giving results which were classified as: success (90); fracture (56); or loose (54), according to rigid selection criteria. Fracture was associated with heavier patients in which there was poor proximal fixation of the femoral component but adequate distal fixation. Stems with a medial disposition proximally were more common in the fracture group than in the successful or loose groups. Sequential measurements of bending and subsequent fracture were made on the follow-up radiographs of 24 of the 200 cases (6 fracture and 18 successful). These measurements allowed bending to be detected at an earlier stage than by simple inspection of the radiographs.

Summary In providing services to children educational psychologists can omit giving help directly to parents. Stress management training is available in industry and to teachers; why not carers? This paper outlines an approach to using such techniques to help parents of children with special educational needs.

The prevalence of recurrent caries was recorded at the annual examinations of a 3-year double-blind caries clinical trial involving 4,294 children age 12-13 years at baseline. Recurrent caries was defined as clinically apparent disease affecting the restoration margins. Examination of all surfaces of undried teeth was carried out using a CPITN-C probe. The proportion of children with recurrent caries was 7.5, 9.5, 6.3 and 8.0% at baseline, year 1, year 2, and year 3. The proportions of restorations with recurrent caries was 1.9, 1.8, 1.0 and 1.1%, respectively, at each examination. A number of oral hygiene parameters were collected via a computer questionnaire. Water rinsing after brushing proved to be associated with recurrent caries (p0.01), those using a beaker having more recurrent caries than those using less diluting methods. Subjects who brushed twice a day (at the final examination) had less recurrent caries than those reporting to brush less often (p0.01). Both these results are consistent with previous findings on the association between DMFS increments and oral hygiene practices.

The position of charities in the UK has become a topic of growing concern. The House of Commons Expenditure Committee in its Tenth Report for the Session 1974–75 reviewed the role of the Charity Commissioners and their accountability. The Goodman Committee reported in 1976 on charity law and voluntary organisation and the report of the Wolfenden Committee in 1978 has stimulated further interest. However, constraints on public expenditure have given the whole question a more topical interest, and particularly within the context of how voluntary organisations might best be stimulated. In the Government's budget for 1980 and 1981 tax relief changes exemplify the interest in encouraging voluntary effort. In 1980, for example, tax relief for payments under deed of covenant was extended to the higher rates of tax subject to a ceiling of £3,000 a year, and the effective minimum period was reduced from seven to four years. Tax exemptions for bequests were doubled and exemption was allowed from development land tax for all disposals of land. In 1981 there was a widening of capital tax relief for trusts for disabled people and an increase in value added tax relief for charities serving the disabled.

The present day museum is a far cry from the original concept but is it what the public wants?

Total cross sections have been measured for electron capture and stripping of ${\mathrm{He}}^{+}$, ${\mathrm{Ne}}^{+}$, and ${\mathrm{A}}^{+}$ ions in single collisions of ${\mathrm{He}}^{+}$ on He, Ne, and A; ${\mathrm{Ne}}^{+}$ on Ne and A; and ${\mathrm{A}}^{+}$ on A. Where ${\mathrm{He}}^{+}$ ions are incident, the cross sections are given for electron capture, ${\ensuremath{\sigma}}_{10}$; for electron loss, ${\ensuremath{\sigma}}_{12}$; and for "elastic" scattering in excess of one degree, ${\ensuremath{\sigma}}_{11}g1\ifmmode^\circ\else\textdegree\fi{}$. Where ${\mathrm{Ne}}^{+}$ and ${\mathrm{A}}^{+}$ are incident, the cross sections for multiple stripping ${\ensuremath{\sigma}}_{13}, \ensuremath{\cdots}, {\ensuremath{\sigma}}_{17}$ are given also. The measurements were made at 25, 50, and 100 kev and at additional energies in two cases where a maximum in the electron capture cross section was observed. Each total cross section was compiled by adding the contributions from the various angular regions into which the incident particle may be scattered. The contribution from the particles scattered between 0\ifmmode^\circ\else\textdegree\fi{} and 1\ifmmode^\circ\else\textdegree\fi{} was measured directly, while that for regions in excess of 1\ifmmode^\circ\else\textdegree\fi{} was obtained by integrating the measured differential cross sections. In the region between 1\ifmmode^\circ\else\textdegree\fi{} and 4\ifmmode^\circ\else\textdegree\fi{} the differential cross section for each process was measured with high resolution and these data are presented here separately. These differential measurements supplement data previously published for angles in excess of 4\ifmmode^\circ\else\textdegree\fi{}. Tables are presented showing the contribution of each of the angular regions to the various total cross sections. Large-angle scattering is found to make a significant contribution to the total cross sections for the production of the more highly ionized particles.

Let F be a field of characteristic p, and if Ω is an n-set let Mn be the vector space over F with basis 2Ω. We continue our investigation of modular homological Sn-representations which arise from the r-step inclusion map. This is the FSn-homomorphism ∂r:Mn→Mn which sends a k-element subset Δ⊆Ω onto the sum of all (k−r)-element subsets of Δ. Using homological methods one can give explicit character and dimension formulae.

We present the results of a retrospective study based on radiographs of 75 successful total hip replacements, and 103 which involved failure of the femoral component of the prosthesis. The failures were selected to exclude cases in which infection was implicated. Success was defined as absence of adverse clinical or radiological symptoms for at least 12 years after surgery. A failure was either obvious, for example, stem fracture, or defined as one which showed progressive radiological and clinical degeneration resulting in the need for revision surgery. Measurements were made on radiographs which had been obtained immediately post-operatively, so that the features measured would depend on surgical procedure rather than on any subsequent biological response. Computer image analysis has been used to make precisely defined, reproducible measurements of 58 parameters characterising the insertion of the femoral component of a standard Charnley prosthesis. These parameters include geometry of insertion, distribution of cement, surrounding bone thickness, and so on. Clinical findings, including patient weight, were also recorded with the measurements on computer disc. Preliminary statistical comparisons indicate that several of the measured parameters are of predictive value for determining the long-term success or failure of total hip replacements.

The class of completely simple semigroups forms a variety when considered as semigroups with the additional unary operation x ↦ x −1 , x −1 being the inverse of x in the subgroup H x . We present a Rees matrix representation for the -free product of any family of completely simple semigroups and for the -free product of any amalgam of completely simple semigroups. From the former, a description of the free semigroups in and of certain free idempotent-generated semigroups in is easily deduced. We then consider the lattice of subvarieties of . Also discussed are injectives and projectives in and a problem concerning the Hopf property.

A method has been developed for quantifying movement and wear of the acetabular component (cup) of total hip replacements (THR) from routine postoperative and review radiographs. The method uses both interactive and automatic computer image analysis techniques. Dimensions of the prosthesis are used to scale the measurements and so overcome variation in radiographic alignment. The application of the method is illustrated by retrospective investigations of cup migration and wear using review radiographs taken over a follow-up of at least 12 years.

Early spermatids of Platichthys flesus (flounder) have a central spherical nucleus and cytoplasm with numerous dispersed mitochondria and a pair of peripheral centrioles. One of the centrioles acts as a kinetosome for axoneme formation. After the start of chromatin condensation the centrioles and developing axoneme migrate to adopt a tangential orientation adjacent to a flattened, lateral margin of the nucleus. During migration, pericentriolar material becomes reorganised. The proximal centriole becomes surrounded by nine fibres, and the distal centriole by a complex collar. As the nucleus condenses it undergoes a rotation which shifts it to the anterior of the centrioles and deepens the articular fossa which houses, and is connected to, the two centrioles and their associated structures. This rotation also results in the mitochondria becoming relocated to form a ring around the proximal region of the axoneme to give the cell its mature ultrastructure.

The ultrastructure of the spermatozoon of Platichthys flesus (flounder) has been determined. The cell is of the primitive type and lacks an acrosome. The bullet-shaped, homogeneously electron-dense nucleus has a deep, caudal articular fossa containing proximal and distal centrioles. Both centrioles are embedded in pericentriolar material which is intimately associated with the nuclear envelope. Around the proximal centriole the material is organised into a dense ring which bears nine fibres associated with the triplets, and a large fibrous body, all connected to the nuclear envelope. Connections exist also between the pericentriolar material of the proximal and distal centrioles. The material around the distal centriole is organised into a complex collar. The anterior surfaces of eight spherical mitochondria lie within shallow depressions of the nuclear caudal surface. They form a ring surrounding the posterior opening of the articular fossa and the proximal region of the 9 + 2 flagellar axoneme.