University of Hull

Abstract DNA degradation, low DNA concentrations and primer‐site mutations may result in the incorrect assignment of microsatellite genotypes, potentially biasing population genetic analyses. micro ‐ checker is windows ®‐based software that tests the genotyping of microsatellites from diploid populations. The program aids identification of genotyping errors due to nonamplified alleles (null alleles), short allele dominance (large allele dropout) and the scoring of stutter peaks, and also detects typographic errors. micro ‐ checker estimates the frequency of null alleles and, importantly, can adjust the allele and genotype frequencies of the amplified alleles, permitting their use in further population genetic analysis. micro ‐ checker can be freely downloaded from http://www.microchecker.hull.ac.uk/ .

BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: =0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca.

Journal Article Measures of multivariate skewness and kurtosis with applications Get access K. V. MARDIA K. V. MARDIA University of Hull Search for other works by this author on: Oxford Academic Google Scholar Biometrika, Volume 57, Issue 3, December 1970, Pages 519–530, https://doi.org/10.1093/biomet/57.3.519 Published: 01 December 1970 Article history Revision received: 01 March 1970 Received: 01 December 1970 Published: 01 December 1970

BACKGROUND: Approximately 30% of people over 65 years of age living in the community fall each year. This is an update of a Cochrane review first published in 2009. OBJECTIVES: To assess the effects of interventions designed to reduce the incidence of falls in older people living in the community. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (February 2012), CENTRAL (The Cochrane Library 2012, Issue 3), MEDLINE (1946 to March 2012), EMBASE (1947 to March 2012), CINAHL (1982 to February 2012), and online trial registers. SELECTION CRITERIA: Randomised trials of interventions to reduce falls in community-dwelling older people. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed risk of bias and extracted data. We used a rate ratio (RaR) and 95% confidence interval (CI) to compare the rate of falls (e.g. falls per person year) between intervention and control groups. For risk of falling, we used a risk ratio (RR) and 95% CI based on the number of people falling (fallers) in each group. We pooled data where appropriate. MAIN RESULTS: We included 159 trials with 79,193 participants. Most trials compared a fall prevention intervention with no intervention or an intervention not expected to reduce falls. The most common interventions tested were exercise as a single intervention (59 trials) and multifactorial programmes (40 trials). Sixty-two per cent (99/159) of trials were at low risk of bias for sequence generation, 60% for attrition bias for falls (66/110), 73% for attrition bias for fallers (96/131), and only 38% (60/159) for allocation concealment.Multiple-component group exercise significantly reduced rate of falls (RaR 0.71, 95% CI 0.63 to 0.82; 16 trials; 3622 participants) and risk of falling (RR 0.85, 95% CI 0.76 to 0.96; 22 trials; 5333 participants), as did multiple-component home-based exercise (RaR 0.68, 95% CI 0.58 to 0.80; seven trials; 951 participants and RR 0.78, 95% CI 0.64 to 0.94; six trials; 714 participants). For Tai Chi, the reduction in rate of falls bordered on statistical significance (RaR 0.72, 95% CI 0.52 to 1.00; five trials; 1563 participants) but Tai Chi did significantly reduce risk of falling (RR 0.71, 95% CI 0.57 to 0.87; six trials; 1625 participants).Multifactorial interventions, which include individual risk assessment, reduced rate of falls (RaR 0.76, 95% CI 0.67 to 0.86; 19 trials; 9503 participants), but not risk of falling (RR 0.93, 95% CI 0.86 to 1.02; 34 trials; 13,617 participants).Overall, vitamin D did not reduce rate of falls (RaR 1.00, 95% CI 0.90 to 1.11; seven trials; 9324 participants) or risk of falling (RR 0.96, 95% CI 0.89 to 1.03; 13 trials; 26,747 participants), but may do so in people with lower vitamin D levels before treatment.Home safety assessment and modification interventions were effective in reducing rate of falls (RR 0.81, 95% CI 0.68 to 0.97; six trials; 4208 participants) and risk of falling (RR 0.88, 95% CI 0.80 to 0.96; seven trials; 4051 participants). These interventions were more effective in people at higher risk of falling, including those with severe visual impairment. Home safety interventions appear to be more effective when delivered by an occupational therapist.An intervention to treat vision problems (616 participants) resulted in a significant increase in the rate of falls (RaR 1.57, 95% CI 1.19 to 2.06) and risk of falling (RR 1.54, 95% CI 1.24 to 1.91). When regular wearers of multifocal glasses (597 participants) were given single lens glasses, all falls and outside falls were significantly reduced in the subgroup that regularly took part in outside activities. Conversely, there was a significant increase in outside falls in intervention group participants who took part in little outside activity.Pacemakers reduced rate of falls in people with carotid sinus hypersensitivity (RaR 0.73, 95% CI 0.57 to 0.93; three trials; 349 participants) but not risk of falling. First eye cataract surgery in women reduced rate of falls (RaR 0.66, 95% CI 0.45 to 0.95; one trial; 306 participants), but second eye cataract surgery did not.Gradual withdrawal of psychotropic medication reduced rate of falls (RaR 0.34, 95% CI 0.16 to 0.73; one trial; 93 participants), but not risk of falling. A prescribing modification programme for primary care physicians significantly reduced risk of falling (RR 0.61, 95% CI 0.41 to 0.91; one trial; 659 participants).An anti-slip shoe device reduced rate of falls in icy conditions (RaR 0.42, 95% CI 0.22 to 0.78; one trial; 109 participants). One trial (305 participants) comparing multifaceted podiatry including foot and ankle exercises with standard podiatry in people with disabling foot pain significantly reduced the rate of falls (RaR 0.64, 95% CI 0.45 to 0.91) but not the risk of falling.There is no evidence of effect for cognitive behavioural interventions on rate of falls (RaR 1.00, 95% CI 0.37 to 2.72; one trial; 120 participants) or risk of falling (RR 1.11, 95% CI 0.80 to 1.54; two trials; 350 participants).Trials testing interventions to increase knowledge/educate about fall prevention alone did not significantly reduce the rate of falls (RaR 0.33, 95% CI 0.09 to 1.20; one trial; 45 participants) or risk of falling (RR 0.88, 95% CI 0.75 to 1.03; four trials; 2555 participants).No conclusions can be drawn from the 47 trials reporting fall-related fractures.Thirteen trials provided a comprehensive economic evaluation. Three of these indicated cost savings for their interventions during the trial period: home-based exercise in over 80-year-olds, home safety assessment and modification in those with a previous fall, and one multifactorial programme targeting eight specific risk factors. AUTHORS' CONCLUSIONS: Group and home-based exercise programmes, and home safety interventions reduce rate of falls and risk of falling.Multifactorial assessment and intervention programmes reduce rate of falls but not risk of falling; Tai Chi reduces risk of falling.Overall, vitamin D supplementation does not appear to reduce falls but may be effective in people who have lower vitamin D levels before treatment.

Polyhydroxyalkanoates (PHAs), of which polyhydroxybutyrate (PHB) is the most abundant, are bacterial carbon and energy reserve materials of widespread occurrence. They are composed of 3-hydroxyacid monomer units and exist as a small number of cytoplasmic granules per cell. The properties of the C4 homopolymer PHB as a biodegradable thermoplastic first attracted industrial attention more than 20 years ago. Copolymers of C4 (3-hydroxybutyrate [3HB]) and C5 (3-hydroxyvalerate [3HV]) monomer units have modified physical properties; e.g., the plastic is less brittle than PHB, whereas PHAs containing C8 to C12 monomers behave as elastomers. This family of materials is the centre of considerable commercial interest, and 3HB-co-3HV copolymers have been marketed by ICI plc as Biopol. The known polymers exist as 2(1) helices with the fiber repeat decreasing from 0.596 nm for PHB to about 0.45 nm for C8 to C10 polymers. Novel copolymers with a backbone of 3HB and 4HB have been obtained. The native granules contain noncrystalline polymer, and water may possibly act as a plasticizer. Although the biosynthesis and regulation of PHB are generally well understood, the corresponding information for the synthesis of long-side-chain PHAs from alkanes, alcohols, and organic acids is still incomplete. The precise mechanisms of action of the polymerizing and depolymerizing enzymes also remain to be established. The structural genes for the three key enzymes of PHB synthesis from acetyl coenzyme A in Alcaligenes eutrophus have been cloned, sequenced, and expressed in Escherichia coli. Polymer molecular weights appear to be species specific. The factors influencing the commercial choice of organism, substrate, and isolation process are discussed. The physiological functions of PHB as a reserve material and in symbiotic nitrogen fixation and its presence in bacterial plasma membranes and putative role in transformability and calcium signaling are also considered.

BACKGROUND: Meta-analyses of antidepressant medications have reported only modest benefits over placebo treatment, and when unpublished trial data are included, the benefit falls below accepted criteria for clinical significance. Yet, the efficacy of the antidepressants may also depend on the severity of initial depression scores. The purpose of this analysis is to establish the relation of baseline severity and antidepressant efficacy using a relevant dataset of published and unpublished clinical trials. METHODS AND FINDINGS: We obtained data on all clinical trials submitted to the US Food and Drug Administration (FDA) for the licensing of the four new-generation antidepressants for which full datasets were available. We then used meta-analytic techniques to assess linear and quadratic effects of initial severity on improvement scores for drug and placebo groups and on drug-placebo difference scores. Drug-placebo differences increased as a function of initial severity, rising from virtually no difference at moderate levels of initial depression to a relatively small difference for patients with very severe depression, reaching conventional criteria for clinical significance only for patients at the upper end of the very severely depressed category. Meta-regression analyses indicated that the relation of baseline severity and improvement was curvilinear in drug groups and showed a strong, negative linear component in placebo groups. CONCLUSIONS: Drug-placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients. The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.

An association analysis was made of the responses of young adults to a hand‐preference questionnaire. Many patterns of preference were distinguished and there were no marked differences between adjacent classes. These findings are believed to demonstrate that hand preference is distributed continuously and not discretely. When it is necessary to classify handedness, the preference continuum can be divided at several levels of discrimination. A second study of hand preference and manual speed showed that it is possible to order the main preference groups for asymmetry of manual skill. Some of the problems of studies of laterality are examined as possible consequences of the treatment of a continuous distribution as if it were discrete.

This compilation contains critically evaluated kinetic data on elementary homogeneous gas phase for use in modelling processes. Data sheets are presented for some 196 Each data sheet sets out relevant data, rate coefficient measurements, an assessment of the reliability of the data, references, and recommended rate parameters. Tables summarizing the preferred rate data are also given. The considered are limited largely to those involved in the of and ethane in air but a few relevant to the chemistry of exhaust gases and to the of aromatic compounds are also included.

Wound healing is a complex, dynamic process supported by a myriad of cellular events that must be tightly coordinated to efficiently repair damaged tissue. Derangement in wound-linked cellular behaviours, as occurs with diabetes and ageing, can lead to healing impairment and the formation of chronic, non-healing wounds. These wounds are a significant socioeconomic burden due to their high prevalence and recurrence. Thus, there is an urgent requirement for the improved biological and clinical understanding of the mechanisms that underpin wound repair. Here, we review the cellular basis of tissue repair and discuss how current and emerging understanding of wound pathology could inform future development of efficacious wound therapies.

Journal Article Small states in world markets: industrial policy in Europe Get access Small states in world markets: industrial policy in Europe. By Peter J. Katzenstein. Ithaca, NY, London: Cornell University Press. 1985. 268pp. Index. $29.95; ISBN 0 8014 1729 5. Pb.: $10.95; ISBN 0 8014 9326 9. Jack Hayward Jack Hayward 1University of Hull Search for other works by this author on: Oxford Academic Google Scholar International Affairs, Volume 62, Issue 2, spring 1986, Page 318, https://doi.org/10.2307/2618414 Published: 01 April 1986

This compilation updates and expands a previous evaluation of kinetic data on elementary, homogeneous, gas phase reactions of neutral species involved in combustion systems [J. Phys. Chem. Ref. Data 21, 411 (1992)]. The work has been carried out under the auspices of the European Community Energy Research and Development Program. Data sheets are presented for some 78 reactions and two tables in which preferred rate parameters are presented for reactions of ethyl, i-propyl, t-butyl, and allyl radicals are given. Each data sheet sets our relevant thermodynamic data, experimental kinetic data, references, and recommended rate parameters with their error limits. A table summarizing the recommended rate data is also given. The new reactions fall into two categories: first, to expand the previous compilation relating largely to the combustion in air of methane, ethane and aromatic compounds; and second, provide data for some of the key radicals involved in the combustion of higher alkanes.

Context. Measurement of the Galactic neutral atomic hydrogen (H i) column density, N H i , and brightness temperatures, T B , is of high scientific value for a broad range of astrophysical disciplines. In the past two decades, one of the most-used legacy H i datasets has been the Leiden/Argentine/Bonn Survey (LAB).

BACKGROUND: The European Society of Cardiology (ESC) has published guidelines for the investigation of patients with suspected heart failure and, if the diagnosis is proven, their subsequent management. Hospitalisation provides a key point of care at which time diagnosis and treatment may be refined to improve outcome for a group of patients with a high morbidity and mortality. However, little international data exists to describe the features and management of such patients. Accordingly, the EuroHeart Failure survey was conducted to ascertain if appropriate tests were being performed with which to confirm or refute a diagnosis of heart failure and how this influenced subsequent management. METHODS: The survey screened consecutive deaths and discharges during 2000-2001 predominantly from medical wards over a 6-week period in 115 hospitals from 24 countries belonging to the ESC, to identify patients with known or suspected heart failure. RESULTS: A total of 46788 deaths and discharges were screened from which 11327 (24%) patients were enrolled with suspected or confirmed heart failure. Forty-seven percent of those enrolled were women. Fifty-one percent of women and 30% of men were aged >75 years. Eighty-three percent of patients had a diagnosis of heart failure made on or prior to the index admission. Heart failure was the principal reason for admission in 40%. The great majority of patients (>90%) had had an ECG, chest X-ray, haemoglobin and electrolytes measured as recommended in ESC guidelines, but only 66% had ever had an echocardiogram. Left ventricular ejection fraction had been measured in 57% of men and 41% of women, usually by echocardiography (84%) and was <40% in 51% of men but only in 28% of women. Forty-five percent of women and 22% of men were reported to have normal left ventricular systolic function by qualitative echocardiographic assessment. A substantial proportion of patients had alternative explanations for heart failure other than left ventricular systolic or diastolic dysfunction, including valve disease. Within 12 weeks of discharge, 24% of patients had been readmitted. A total of 1408 of 10434 (13.5%) patients died between admission and 12 weeks follow-up. CONCLUSIONS: Known or suspected heart failure comprises a large proportion of admissions to medical wards and such patients are at high risk of early readmission and death. Many of the basic investigations recommended by the ESC were usually carried out, although it is not clear whether this was by design or part of a general routine for all patients being admitted regardless of diagnosis. The investigation most specific for patients with suspected heart failure (echocardiography) was performed less frequently, suggesting that the diagnosis of heart failure is still relatively neglected. Most men but a minority of women who underwent investigation of cardiac function had evidence of moderate or severe left ventricular dysfunction, the main target of current advances in the treatment of heart failure. Considerable diagnostic uncertainty remains for many patients with suspected heart failure, even after echocardiography, which must be resolved in order to target existing and new therapies and services effectively.

The ability of pathogens to obtain iron from transferrins, ferritin, hemoglobin, and other iron-containing proteins of their host is central to whether they live or die. To combat invading bacteria, animals go into an iron-withholding mode and also use a protein (Nramp1) to generate reactive oxygen species in an attempt to kill the pathogens. Some invading bacteria respond by producing specific iron chelators-siderophores-that remove the iron from the host sources. Other bacteria rely on direct contact with host iron proteins, either abstracting the iron at their surface or, as with heme, taking it up into the cytoplasm. The expression of a large number of genes (>40 in some cases) is directly controlled by the prevailing intracellular concentration of Fe(II) via its complexing to a regulatory protein (the Fur protein or equivalent). In this way, the biochemistry of the bacterial cell can accommodate the challenges from the host. Agents that interfere with bacterial iron metabolism may prove extremely valuable for chemotherapy of diseases.

OBJECTIVES: To assess the effectiveness of beta blockers in short term treatment for acute myocardial infarction and in longer term secondary prevention; to examine predictive factors that may influence outcome and therefore choice of drug; and to examine the clinical importance of the results in the light of current treatment. DESIGN: Systematic review of randomised controlled trials. SETTING: Randomised controlled trials. SUBJECTS: Patients with acute or past myocardial infarction. INTERVENTION: beta Blockers compared with control. MAIN OUTCOME MEASURES: All cause mortality and non-fatal reinfarction. RESULTS: Overall, 5477 of 54 234 patients (10.1%) randomised to beta blockers or control died. We identified a 23% reduction in the odds of death in long term trials (95% confidence interval 15% to 31%), but only a 4% reduction in the odds of death in short term trials (-8% to 15%). Meta regression in long term trials did not identify a significant reduction in effectiveness in drugs with cardioselectivity but did identify a near significant trend towards decreased benefit in drugs with intrinsic sympathomimetic activity. Most evidence is available for propranolol, timolol, and metoprolol. In long term trials, the number needed to treat for 2 years to avoid a death is 42, which compares favourably with other treatments for patients with acute or past myocardial infarction. CONCLUSIONS: beta Blockers are effective in long term secondary prevention after myocardial infarction, but they are underused in such cases and lead to avoidable mortality and morbidity.

AIMS: Many patients who receive a diagnosis of heart failure have neither a low left ventricular (LV) ejection fraction nor valve disease. Few substantial randomized controlled trials have been conducted in this population, none has focussed on patients with evidence of diastolic dysfunction and none has shown clear benefit on symptoms, morbidity, or mortality. METHODS AND RESULTS: This was a randomized double-blind trial, comparing placebo with perindopril, 4 mg/day in patients aged > or =70 years with a diagnosis of heart failure, treated with diuretics and an echocardiogram suggesting diastolic dysfunction and excluding substantial LV systolic dysfunction or valve disease. The primary endpoint was a composite of all-cause mortality and unplanned heart failure related hospitalization with a minimum follow-up of 1 year. A total of 850 patients were randomized. Their mean age was 76 (SD 5) years and 55% were women. Median follow-up was 2.1 (IQR 1.5-2.8) years. Enrollment and event rates were lower than anticipated, reducing the power of the study to show a difference in the primary endpoint to 35%. Many patients withdrew from perindopril (28%) and placebo (26%) after 1 year and started taking open-label ACE-inhibitors. Overall, 107 patients assigned to placebo and 100 assigned to perindopril reached the primary endpoint (HR 0.919: 95% CI 0.700-1.208; P = 0.545). By 1 year, reductions in the primary outcome (HR 0.692: 95% CI 0.474-1.010; P = 0.055) and hospitalization for heart failure (HR 0.628: 95% CI 0.408-0.966; P = 0.033) were observed and functional class (P < 0.030) and 6-min corridor walk distance (P = 0.011) had improved in those assigned to perindopril. CONCLUSION: Uncertainty remains about the effects of perindopril on long-term morbidity and mortality in this clinical setting since this study had insufficient power for its primary endpoint. However, improved symptoms and exercise capacity and fewer hospitalizations for heart failure in the first year were observed on perindopril, during which most patients were on assigned therapy, suggesting that it may be of benefit in this patient population.

Abstract We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15 yr pulsar timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings–Downs pattern expected for a stochastic gravitational-wave background. The presence of such a gravitational-wave background with a power-law spectrum is favored over a model with only independent pulsar noises with a Bayes factor in excess of 10 14 , and this same model is favored over an uncorrelated common power-law spectrum model with Bayes factors of 200–1000, depending on spectral modeling choices. We have built a statistical background distribution for the latter Bayes factors using a method that removes interpulsar correlations from our data set, finding p = 10 −3 (≈3 σ ) for the observed Bayes factors in the null no-correlation scenario. A frequentist test statistic built directly as a weighted sum of interpulsar correlations yields p = 5 × 10 −5 to 1.9 × 10 −4 (≈3.5 σ –4 σ ). Assuming a fiducial f −2/3 characteristic strain spectrum, as appropriate for an ensemble of binary supermassive black hole inspirals, the strain amplitude is <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mn>2.4</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.6</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.7</mml:mn> </mml:mrow> </mml:msubsup> <mml:mo>×</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>15</mml:mn> </mml:mrow> </mml:msup> </mml:math> (median + 90% credible interval) at a reference frequency of 1 yr −1 . The inferred gravitational-wave background amplitude and spectrum are consistent with astrophysical expectations for a signal from a population of supermassive black hole binaries, although more exotic cosmological and astrophysical sources cannot be excluded. The observation of Hellings–Downs correlations points to the gravitational-wave origin of this signal.

This compilation updates and expands two previous evaluations of kinetic data on elementary, homogeneous, gas phase reactions of neutral species involved in combustion systems [J. Phys. Chem. Ref Data 21, 411 (1992); 23, 847 (1994)]. The work has been carried out under the auspices of the IUPAC Commission on Chemical Kinetics and the UK Engineering and Physical Sciences Research Council. Individual data sheets are presented for most reactions but the kinetic data for reactions of C2, C, ethyl, i-propyl, t-butyl, and allyl radicals are summarized in tables. Each data sheet sets out relevant thermodynamic data, experimental kinetic data, references, recommended rate parameters with their error limits and a brief discussion of the reasons for their selection. Where appropriate the data are displayed on an Arrhenius diagram or by fall-off curves. Tables summarizing the recommended rate data and the thermodynamic data for the reactant and product species are given, and their sources referenced. As in the previous evaluations the reactions considered relate largely to the combustion in air of organic compounds containing up to three carbon atoms and simple aromatic compounds. Thus the data base has been expanded, largely by dealing with a substantial number of extra reactions within these general areas.

BACKGROUND: Approximately 30 per cent of people over 65 years of age and living in the community fall each year; the number is higher in institutions. Although less than one fall in 10 results in a fracture, a fifth of fall incidents require medical attention. OBJECTIVES: To assess the effects of interventions designed to reduce the incidence of falls in elderly people (living in the community, or in institutional or hospital care). SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Group specialised register (January 2001), Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2001), MEDLINE (1966 to February 2001), EMBASE (1988 to 2001 Week 14), CINAHL (1982 to March 2001), The National Research Register, Issue 1, 2001, Current Controlled Trials (www.controlled-trials.com accessed 25 May 2001), and reference lists of articles. We also contacted researchers in the field. SELECTION CRITERIA: Randomised trials of interventions designed to minimise the effect of, or exposure to, risk factors for falling in elderly people. Main outcomes of interest were the number of fallers, or falls. Trials reporting only intermediate outcomes were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. Data were pooled using the fixed effect model where appropriate. MAIN RESULTS: Interventions likely to be beneficial: ~bullet~A programme of muscle strengthening and balance retraining, individually prescribed at home by a trained health professional (3 trials, 566 participants, pooled relative risk (RR) 0.80, 95% confidence interval (95%CI) 0.66 to 0.98). ~bullet~A 15 week Tai Chi group exercise intervention (1 trial, 200 participants, risk ratio 0.51, 95%CI 0.36 to 0.73). ~bullet~Home hazard assessment and modification that is professionally prescribed for older people with a history of falling (1 trial, 530 participants, RR 0.64, 95% CI 0.49 to 0.84). A reduction in falls was seen both inside and outside the home. ~bullet~Withdrawal of psychotropic medication (1 trial, 93 participants, relative hazard 0.34, 95%CI 0.16 to 0.74). ~bullet~Multidisciplinary, multifactorial, health/environmental risk factor screening/intervention programmes, both for unselected community dwelling older people (data pooled from 3 trials, 1973 participants, pooled RR 0.73, 95%CI 0.63 to 0.86), and for older people with a history of falling, or selected because of known risk factors (data pooled from 2 trials, 713 participants, pooled RR 0.79, 95%CI 0.67 to 0.94). Interventions of unknown effectiveness: ~bullet~Group-delivered exercise interventions (9 trials, 2177 participants). ~bullet~Nutritional supplementation (1 trial, 50 participants). ~bullet~Vitamin D supplementation, with or without calcium (3 trials, 679 participants). ~bullet~Home hazard modification in association with advice on optimising medication (1 trial, 658 participants), or in association with an education package on exercise and reducing fall risk (1 trial, 3182 participants). ~bullet~Pharmacological therapy (raubasine-dihydroergocristine, 1 trial, 95 participants). ~bullet~Fall prevention programmes in institutional settings. ~bullet~Interventions using a cognitive/behavioural approach alone (2 trials, 145 participants). ~bullet~Home hazard modification for older people without a history of falling (1 trial, 530 participants). ~bullet~ Hormone replacement therapy (1 trial, 116 participants). Interventions unlikely to be beneficial: ~bullet~Brisk walking in women with an upper limb fracture in the previous two years (1 trial, 165 participants). REVIEWER'S CONCLUSIONS: Interventions to prevent falls that are likely to be effective are now available; less is known about their effectiveness in preventing fall-related injuries. Costs per fall prevented have been established for four of the interventions and careful economic modelling in the context of the local healthcare system is important. Some potential interventions are of unknown effectiveness and further research is indicated.

A systematic investigation into the influence of the wettability of spherical, nanometer-sized silica particles on the type and stability of water−toluene emulsions is described. The particles range from hydrophilic to hydrophobic depending on the extent of chemisorbed silane on their surfaces. We show that predictions based on considerations of the energy of attachment of a single particle to the oil−water interface relate directly to the stability of emulsions. A combination of powder immersion, shelf stability, light diffraction, and microscopy measurements is used to characterize the systems. Emulsions stabilized by either very hydrophilic or very hydrophobic particles are large (>100 μm) and unstable to coalescence. Those with particles of intermediate hydrophobicity are submicrometer and stable to coalescence indefinitely. For these, catastrophic inversion of emulsions occurs upon increasing the volume fraction of water, φw, and their stability to sedimentation or creaming increases approaching inversion. The stability of emulsions to gravity-induced separation passes through a sharp maximum upon increasing the particle hydrophobicity, alongside a minimum in the average drop diameter. This is universal and independent of φw and the type of emulsion formed. In one system, an otherwise very stable water-in-oil emulsion is destabilized in an ultracentrifugal field leading to enhanced sedimentation and eventual coalescence.