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[Cu(HF2)(pyz)2]BF4 consists of rare µ1,3 bridging HF2 anions and µ-pyrazine ligands leading to a 3D pseudo-cubic framework that antiferromagnetically orders below 1.54(1) K.

The rare-earth ferroelectromagnet YMnO3 consists of weakly coupled triangular layers of S=2 spins. Below T_N ~ 70 K muon-spin relaxation data show two oscillatory relaxing signals due to magnetic order, with no relaxing signal resolvable (which would be expected for different coexisting spin distributions). The transition temperature T_N increases with applied hydrostatic pressure, even though the ordered moment decreases. These results suggest that pressure increases both the exchange coupling between the layers and the frustration within the layers., Comment: 4 pages, 3 figures, v2 (updated figures and minor changes to text)

We present the results of muon-spin relaxation ($\mu^{+}$SR) measurements on the kagome staircase compounds Ni$_{3}$V$_{2}$O$_{8}$ and Co$_{3}$V$_{2}$O$_{8}$. The magnetic behavior of these materials may be described in terms of two inequivalent magnetic ion sites, known as spine sites and cross-tie sites. Our $\mu^{+}$SR results allow us to probe each of these sites individually, revealing the distribution of the local magnetic fields near these positions. We are able not only to confirm the magnetic structures of the various phases proposed on the basis of bulk measurements but also to give an insight into the temperature evolution of the local field distribution in each phase., Comment: 9 pages, 5 figures, added references, corrected typos, revised figure 3

BACKGROUND: The workplace has potential as a setting through which large groups of people can be reached to encourage smoking cessation. OBJECTIVES: To categorise workplace interventions for smoking cessation tested in controlled studies and to determine the extent to which they help workers to stop smoking or to reduce tobacco consumption. SEARCH STRATEGY: We searched the Tobacco Addiction Review Group trials register in November 2002, Medline (1966 - November 2002), EMBASE (1985 - November 2002) and PsycINFO (to November 2002). We searched abstracts from international conferences on tobacco and we checked the bibliographies of identified studies and reviews for additional references. SELECTION CRITERIA: We categorised interventions into two groups: a) Interventions aimed at the individual to promote smoking cessation and b) interventions aimed at the workplace as a whole. We applied different inclusion criteria for the different types of study. For interventions aimed at helping individuals to stop smoking, we included only randomised controlled trials allocating individuals, workplaces or companies to intervention or control conditions. For studies of smoking restrictions and bans in the workplace, we also included controlled trials with baseline and post-intervention outcomes and interrupted times series studies. DATA COLLECTION AND ANALYSIS: Information relating to the characteristics and content of all kinds of interventions, participants, outcomes and methods of the study was abstracted by one reviewer and checked by two others. Because of heterogeneity in the design and content of the included studies, we did not attempt formal meta-analysis, and evaluated the studies using qualitative narrative synthesis. MAIN RESULTS: Workplace interventions aimed at helping individuals to stop smoking included nine studies of group therapy, three studies of individual counselling, eight studies of self-help materials and four studies of nicotine replacement therapy. The results were consistent with those found in other settings. Group programmes, individual counselling and nicotine replacement therapy increased cessation rates in comparison to no treatment or minimal intervention controls. Self-help materials were less effective. Workplace interventions aimed at the workforce as a whole included 13 studies of tobacco bans, two studies of social support, four studies of environmental support, four studies of incentives, six studies of comprehensive (multi-component) programmes and two studies of competitions and recruitment. Tobacco bans decreased cigarette consumption during the working day but their effect on total consumption was less certain. We failed to detect an increase in quit rates from adding social and environmental support to these programmes. There was a lack of evidence that comprehensive programmes reduced the prevalence of smoking. Competitions and incentives increased attempts to stop smoking, though there was less evidence that they increased the rate of actual quitting. REVIEWER'S CONCLUSIONS: We found 1. Strong evidence that interventions directed towards individual smokers increase the likelihood of quitting smoking. These include advice from a health professional, individual and group counselling and pharmacological treatment to overcome nicotine addiction. Self-help interventions are less effective. All these interventions are effective whether offered in the workplace or elsewhere. Although people taking up these interventions are more likely to stop, the absolute numbers who quit are low. 2. Limited evidence that participation in programmes can be increased by competitions and incentives organised by the employer. 3. Consistent evidence that workplace tobacco policies and bans can decrease cigarette consumption during the working day by smokers and exposure of non-smoking employees to environmental tobacco smoke at work, but conflicting evidence about whether they decrease prevalence of smoking or overall consumption of tobacco by smokers. 4. A lack of evidence that comprehensive approaches reduce the prevalence of smoking, despite the strong theoretical rationale for their use. 5. A lack of evidence about the cost-effectiveness of workplace programmes.

We present experimental evidence for small-moment magnetism below the ferromagnetic transition temperature (T_c3 = 183 K) in the quasi-one-dimensional metal BaIrO_3. Further, we identify rearrangement of the local magnetic moment distribution, which leaves the bulk magnetization unchanged, at the Mott-like transition (T_c1 = 26 K). These results are only possible via muon-spin relaxation ($\mu$SR) techniques, since neutron scattering studies are hindered by the large absorption of neutrons by Ir. The low temperature characteristics of this compound, as revealed by $\mu$SR, are unconventional, and suggest that its magnetic properties are driven by changes occuring at the Fermi surface due to the formation of a charge-density wave state., Comment: 4 pages, 4 figures

We present the first evidence of magnetic order in the quasi-one-dimensional spin 1/2 molecular chain compound, copper pyrazine dinitrate Cu(C4H4N2)(NO3)2}. Zero field muon-spin relaxation measurements made at dilution refrigerator temperatures show oscillations in the measured asymmetry, characteristic of a quasistatic magnetic field at the muon sites. Our measurements provide convincing evidence for long range magnetic order below a temperature T_N=107(1) mK. This leads to an estimate of the interchain coupling constant of |J'|/k_B=0.046 K and to a ratio |J'/J| = 4.4 x 10^-3., Comment: 4 pages, 3 figures. Submitted to Physical Review Letters

We report results of the first muon-spin rotation measurements performed on the low carrier density ferromagnet EuB6. The ferromagnetic state is reached via two magnetic transitions at Tm=15.5 K and T c=12.6 K. Two distinct components are resolved in the muon data, one oscillatory and one non-oscillatory, which arise from different types of magnetic environment, and we have followed the temperature dependence of these components in detail. These results provide evidence for magnetic phase separation and can be interpreted in terms of the gradual coalescing of magnetic polarons.

We report results of the first muon-spin rotation measurements performed on the low carrier density ferromagnet EuB$_6$. The ferromagnetic state is reached via two magnetic transitions at $T_{\rm m}=16.5$ K and $T_{\rm c}=12.6$ K. Two distinct components are resolved in the muon data, one oscillatory and one non-oscillatory, which arise from different types of magnetic environment, and we have followed the temperature dependence of these components in detail. These results provide evidence for magnetic phase separation and can be interpreted in terms of the gradual coalescing of magnetic polarons., Comment: 4 pages, 3 figures

The response of the superconducting charge carriers to an applied magnetic field has been probed in a number of organic superconductors using muSR. Systematic studies have been made of the in-plane superconducting penetration depth lambda in superconductors based on the ET and BETS molecules. These studies have revealed a strong correlation between lambda and T-c. This type of correlation was first noted in high T-c cuprates by Uemura et al who found a linear relation between T-c and lambda(-2). In the case of organic superconductors, however, we find that the overall con-elation is better described as T-c proportional to lambda(-3). Understanding this characteristic trend should provide some important clues about the nature of the superconductivity in the organic superconductors; several possible models are considered here for describing this behaviour. It is concluded that models in which the superconducting carrier concentration is tied to the nominal band filling are inconsistent with the observed scaling behaviour.

OBJECTIVES: To evaluate a special study module in literature and medicine that aimed for clinical relevance. METHODS: We organised a 4-week course around themes such as empathy, death and dying, disability, madness and creativity, addiction, domestic violence, ethical dilemmas, doctor/patient communication, doctors' emotions and end of life decisions. We used a diversity of texts and genres to address these themes. We explicitly encouraged the students to engage with both content and form when studying literature. To evaluate the course we used a nominal group technique. Students identified a range of items in response to open questions about the content and methods of the course. After clarifying and reducing the items generated, they ranked them in order of importance. To investigate perceived clinical relevance, we grouped the individual items into broader themes using a previously suggested taxonomy of clinical relevance. RESULTS: The students attached the highest importance to the insights gained into patients and their experience of illness. These encompassed aspects of understanding, knowledge and empathy. They also perceived that they had improved clinically relevant skills including communication, analysis, presentation, writing and ethical reasoning. The remaining items were more broadly concerned with themes of personal growth, development and pleasure. CONCLUSIONS: There are many objectives in studying literature. We focussed on designing a special study module that explicitly emphasised clinical relevance. Our evaluation shows that students identified clinically relevant improvements in knowledge, skills and attitudes from having taken the course.

Alterations in the extracellular Ca(2+) or K(+) concentration had significant influences on the motility of B16F10 melanoma cells measured in the absence of exogenous integrins using a conventional Boyden chamber assay. At normal K(+) concentrations, motility increased slightly when the concentration of Ca(2+) was increased 10-fold. At normal Ca(2+) concentrations, motility increased by 290% when the extracellular K(+) concentration was reduced 10-fold (from control of 5.4 mM to 0.54 mM), and increased to 250% of control levels when the K(+) concentration was increased between 30 and 54 mM, but was relatively uninfluenced at K(+) concentrations between 5 and 30 mM. Simultaneous application of low concentrations (20 microM) of GdCl(3) completely prevented the effects of low and high K(+) on motility. Exposure to Gd(3+) or Tb(3+) also produced a flattening of the cells and enhanced cell attachment. Although the steady state intracellular Ca(2+) concentration was not significantly influenced by the K(+) concentration, the resting permeability to divalent cations, determined from Mn(2+) quench rates in fura-loaded cells, was significantly increased by a reduction in the K(+) concentration. These results indicate that resting Ca(2+) influx is critical to the movement of B16F10 melanoma cells, and demonstrate that lanthanides, which block resting Ca(2+) influx pathways, are potent antimotility agents.

BACKGROUND: The aim of nicotine replacement therapy (NRT) is to replace nicotine from cigarettes. This reduces withdrawal symptoms associated with smoking cessation thus helping resist the urge to smoke cigarettes. OBJECTIVES: The aims of this review were to determine the effectiveness of the different forms of nicotine replacement therapy (chewing gum, transdermal patches, nasal spray, inhalers and tablets) in achieving abstinence from cigarettes; to determine whether the effect is influenced by the clinical setting in which the smoker is recruited and treated, the dosage and form of the NRT used, or the intensity of additional advice and support offered to the smoker; to determine whether combinations of NRT are more effective than one type alone; and to determine its effectiveness compared to other pharmacotherapies. SEARCH STRATEGY: We searched the Cochrane Tobacco Addiction Group trials register in April 2000. SELECTION CRITERIA: Randomized trials in which NRT was compared to placebo or no treatment, or where different doses of NRT were compared. We excluded trials which did not report cessation rates, and those with follow-up of less than six months. DATA COLLECTION AND ANALYSIS: We extracted data in duplicate on the type of subjects, the dose and duration and form of nicotine therapy, the outcome measures, method of randomisation, and completeness of follow-up. The main outcome measure was abstinence from smoking after at least six months of follow-up. We used the most rigorous definition of abstinence for each trial, and biochemically validated rates if available. Where appropriate, we performed meta-analysis using a fixed effects model. MAIN RESULTS: We identified one hundred trials; of the 88 with a non NRT control group, 48 trials were of nicotine gum, 30 of transdermal nicotine patch, four of intranasal nicotine spray, four of inhaled nicotine and two of nicotine sublingual tablet. Four trials compared combinations of two forms of nicotine therapy with one form alone. The odds ratio for abstinence with NRT compared to control was 1.71 (95% confidence interval 1.60 to 1.82), The odds ratios for the different forms of NRT were 1.63 for gum, 1.73 for patches, 2.27 for nasal spray, 2.08 for inhaled nicotine and 1.73 for nicotine sublingual tablet. These odds were largely independent of the intensity of additional support provided or the setting in which the NRT was offered. Eight weeks of patch therapy was as effective as longer courses and there was no evidence that tapered therapy was better than abrupt withdrawal. Wearing the patch only during waking hours (16 hours/day) was as effective as wearing it for 24 hours/day. The odds ratio for abstinence in the trials which directly compared 4 mg versus 2 mg gum in highly dependent smokers found a significant benefit in favour of 4 mg gum (odds ratio 2.67, 95% confidence interval 1.69 to 4.22). There is no strong evidence that combinations of forms of NRT are more effective. Only one study directly compared NRT to an antidepressant (bupropion). In this study, bupropion was significantly more effective than nicotine patch or placebo. The combination of bupropion and nicotine patch was significantly more effective than nicotine patch alone. There was also a suggestion of greater of efficacy for bupropion and nicotine patch compared to bupropion alone, but the difference was not statistically significant. REVIEWER'S CONCLUSIONS: All of the commercially available forms of NRT (nicotine gum, transdermal patch, the nicotine nasal spray, nicotine inhaler and nicotine sublingual tablets) are effective as part of a strategy to promote smoking cessation. They increase quit rates approximately 1.5 to 2 fold regardless of setting. The effectiveness of NRT appears to be largely independent of the intensity of additional support provided to the smoker. Since all the trials of NRT reported so far have included at least some form of brief advice to the smoker, this represents the minimum which should be offered in order to ensure its effectiveness. Provision of more intense levels of support, although beneficial in facilitating the likelihood of quitting, is not essential to the success of NRT. There is promising evidence that bupropion may be more effective than NRT (either alone or in combination). However, its most appropriate place in the therapeutic armamentarium requires further study and consideration.

BACKGROUND: Brief advice to stop smoking from general practitioners (GPs) has been repeatedly shown to increase smoking cessation by a small, but measurable amount. Some studies have suggested that adding more intensive interventions to brief advice may increase its effectiveness, but it is unclear whether this is true in general practice. AIMS: To determine whether brief advice from a doctor together with counselling and follow-up from a trained practice nurse is more effective than brief advice alone in helping people to stop smoking. METHODS: The design was a randomized controlled trial. Four hundred and ninety-seven general practice patients aged older than 18 years and smoking at least one cigarette per day in six general practices in Oxfordshire, Berkshire, and Buckinghamshire were randomized to one of two interventions: brief verbal or written advice from a GP plus extended counselling and follow-up from a trained practice nurse; brief advice from a GP alone. The primary outcome was sustained abstinence from smoking at three and 12 months. A secondary outcome was forward movement in the stages of change cycle. RESULTS: The proportion showing sustained abstinence was 3.6% in the extended counselling group, and 4.4% in the brief advice group (difference = -0.8%; 95% confidence interval = -4.3% to 2.6%). Seventy-four (30%) of those randomized to extended counselling actually took up this offer. No significant progression in stages of change was detected between the two groups. CONCLUSIONS: In unselected general practice patients who smoke, brief advice from a GP combined with intensive intervention and follow-up by a practice nurse is no more effective than brief advice alone.

OBJECTIVES: To estimate the efficacy of dietary advice to lower blood total cholesterol concentration in free-living subjects and to investigate the efficacy of different dietary recommendations. DESIGN: Systematic overview of 19 randomised controlled trials including 28 comparisons. SUBJECTS: Free-living subjects. INTERVENTIONS: Individualised dietary advice to modify fat intake. MAIN OUTCOME MEASURE: Percentage difference in blood total cholesterol concentration between the intervention and control groups. RESULTS: The percentage reduction in blood total cholesterol attributable to dietary advice after at least six months of intervention was 5.3% (95% confidence interval 4.7% to 5.9%). Including both short and long duration studies, the effect was 8.5% at 3 months and 5.5% at 12 months. Diets equivalent to the step 2 diet of the American Heart Association were of similar efficacy to diets that aimed to lower total fat intake or to raise the polyunsaturated to saturated fatty acid ratio. These diets were moderately more effective than the step 1 diet of the American Heart Association (6.1% v 3.0% reduction in blood total cholesterol concentration; P

OBJECTIVE: To determine the effect of 900 mg/day of dried garlic powder (standardised to 1.3% allicin) in reducing total cholesterol. DESIGN: Double-blind, randomised six-month parallel trial. SUBJECTS: 115 individuals with a repeat total cholesterol concentration of 6.0-8.5 mmol/l and low-density lipoprotein (LDL) cholesterol of 3.5 mmol/l or above after six weeks of dietary advice. INTERVENTION: The active treatment group received dried garlic tablets (standardised to 1.3% allicin) at a dosage of 300 mg three times daily. The control group received a matching placebo. OUTCOME MEASURES: Primary end-point: total cholesterol concentration; secondary end-points: concentrations of LDL and high-density lipoprotein cholesterol, apolipoproteins (apo) A1 and B, and triglycerides. RESULTS: There were no significant differences between the groups receiving garlic and placebo in the mean concentrations of serum lipids, lipoproteins or apo A1 or B, by analysis either on intention-to-treat or treatment received. In a meta-analysis which included the results from this trial, garlic was associated with a mean reduction in total cholesterol of -0.65 mmol/l (95% confidence intervals: -0.53 to -0.76). CONCLUSIONS: In this trial, garlic was less effective in reducing total cholesterol than suggested by previous meta-analyses. Possible explanations are publication bias, overestimation of treatment effects in trials with inadequate concealment of treatment allocation, or a type 2 error. We conclude that meta-analyses should be interpreted critically and with particular caution if the constituent trials are small.

OBJECTIVE: To determine the effectiveness of health checks, performed by nurses in primary care, in reducing risk factors for cardiovascular disease and cancer. DESIGN: Randomised controlled trial. SETTING: Five urban general practices in Bedfordshire. SUBJECTS: 2205 men and women who were randomly allocated a first health check in 1989-90 and a re-examination in 1992-3 (the intervention group); 1916 men and women who were randomly allocated an initial health check in 1992-3 (the control group). All subjects were aged 35-64 at recruitment in 1989. MAIN OUTCOME MEASURES: Serum total cholesterol concentration, blood pressure, body mass index, and smoking prevalence (with biochemical validation of cessation); self reported dietary, exercise, and alcohol habits. RESULTS: Mean serum total cholesterol was 3.1% lower in the intervention group than controls (difference 0.19 mmol/l (95% confidence interval 0.12 to 0.26)); in women it was 4.5% lower (P < 0.0001) and in men 1.6% (P < 0.05), a significant difference between the sexes (P < 0.01). Self reported saturated fat intake was also significantly lower in the intervention group. Systolic and diastolic blood pressures and body mass index were respectively 1.9%, 1.9%, and 1.4% lower in the intervention group (P < 0.005 in all cases). There was a 3.9% (2.4 to 5.3) difference in the percentage of subjects with a cholesterol concentration > or = 8 mmol/l, but no significant differences in the number with diastolic blood pressure > or = 100 mm Hg or body mass index > or = 30 kg/m2. There was no significant difference between the two groups in prevalence of smoking or excessive alcohol use. Annual rechecks were no more effective than a single recheck at three years, but health checks led to a significant increase in visits to the nurse according to patients' degree of cardiovascular risk. CONCLUSIONS: The benefits of health checks were sustained over three years. The main effects were to promote dietary change and reduce cholesterol concentrations; small differences in blood pressure may have been attributable to accommodation to measurement. The benefits of systematic health promotion in primary care are real, but must be weighed against the costs in relation to other priorities.

Although a number of randomized controlled trials of treatment for herpes zoster have been performed, there is no consensus on how it should be managed in general practice. A systematic review of existing trials, including meta-analysis, was performed to determine the efficacy of available therapies in reducing the incidence of postherpetic neuralgia. The treatments studied included antiviral agents, corticosteroids and other drugs which had been studied in randomized trials. Trials were included if the subjects were immunocompetent adults and the intervention was feasible in general practice. The main outcome measure was prevalence of pain at one, three and six months after onset of the acute herpetic rash. Data for each time point were not available for all trials. The quality of studies was also assessed. Pooled analyses of trials with acyclovir failed to detect a significant reduction of pain in the treatment group at one or six months, but found a 35% reduction at three months. Confidence limits were wide, and a modest benefit of treatment cannot be ruled out at one and six months. Pooled analyses were not possible for other treatments, either because too few trials had been performed, or because completed trials demonstrated significant heterogeneity. Many clinical trials in this area have been too small to give reliable results. Variations in the definition and reporting of postherpetic neuralgia create difficulties in combining data from different studies. Firm recommendations for clinical practice are not possible because existing evidence neither confirms nor refutes the hypothesis that treatment during the acute phase of herpes zoster reduces pain later.