297 research outputs found

    The generalized Lindemann melting coefficient

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    Lindemann developed the melting temperature theory over 100 years ago, known as the Lindemann criterion. Its main assumption is that melting occurs when the root-mean-square vibration amplitude of ions and atoms in crystals exceeds a critical fraction, h of the inter-atomic spacing in crystals. The Lindemann coefficient h is undefined and scientific papers report different h values for different elements. Here we present previously unobserved data trends pointing to the fact that the Lindemann coefficient could be linked to the periodic groups of the periodic table, having an exact value for each element belonging to a given periodic group. We report 12 distinctive Lindemann coefficient values corresponding to 12 groups of the periodic table containing solid elements with identifiable melting temperature. Using these vales, the recalculation of the melting temperatures indicates a good match to the experimental values for 39 elements, corresponding to 12 out of 15 periodic groups. This newly observed result opens up the possibility of further refining the Lindemann melting criterion by stimulating analytical studies of the Lindemann coefficient in the light of this newly discovered result

    Use of CYP1B1 inhibitors for treating cancer.

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    CYP1B1 proteins and their role in metabolising or inactivating anti-cancer drugs are disclosed, together with compositions for treating cancer comprising a substance capable of inhibiting CYP1B1 protein and an anti-cancer drug (e.g. docetaxel, paclitaxel, flutamide, tamoxifen, mitoxantrone, doxorubicin or daunomycin)

    Genetic variability in Larus argentatus and Sterna hirundo

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    Blood serum and egg-white protein samples from individuals representing seven colonies of Larusargentatus, and four colonies of Sterna hirundo were electrophoretically analysed to determine levels of genetic variability and to assess the utility of polymorphic loci as genetic markers. Variability occurred at five co-dominant autosomal loci. S. hirundo protein polymorphism occurred at the Est-5 and the Oest-l loci, while nineteen loci were monomorphic. L. argentatus samples were monomorphic at seventeen loci and polymorphic at the Ldh-A and the Alb loci. Intergeneric differences existed at the Oalb and the Ldh-A loci. Although LDH-A100 from both species possessed identical electrophoretLc mobilities, the intergeneric differences were expressed as a difference in enzyme the'ITIlostabilities. Geographical distribution of alleles and genetic divergence estimates suggest ~ hirundo population panmixis,at least at the sampled locations. The h argentatus gene pool appears relatively heterogeneous with a discreet Atlantic Coast population and a Great Lakes demic population. These observed population structures may be maintained by the relative amount of gene flow occurring within and among populations. Mass ringing data coupled to reproductive success information and analysis of dispersal trends appear to validate this assumption. Similar results may be generated by either selection or both small organism and low locus sample sizes. To clarify these results and to detect the major factor(s) affecting the surveyed portions of the genome, larger sample sizes in conjunction with precise eco-demographic data are required

    Dimensional Optimization of Clutch disc with Simulation of Stress Analysis

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    The function of clutch disc is to transmit the power from the engine to the transmission. There are a lot of vehicle that equipped with different size of engine capacity. Therefore, it is required to use a clutch disc with the appropriate capability to transmit the power from the engine. Note that there is a clutch disc modification type that combine the Japanese and European design called clutch disc Hino MB. This type clutch disc is used for Hino FM 260Ti. By using the combination design, the clutch disc will have longer lifetime and lower risk to crack. There is a crack problem that happened from the usage of clutch disc Hino MB. Therefore, it is necessary to do a research to optimize the design of clutch disc Hino MB. This research is done by making several new designs of clutch disc Hino MB and tests it through simulation of stress analysis. The parameter that had been analysed is the value of von mises stress from each design. The length of grooves is also analysed to get a better design result. This research produces a new design of clutch disc Hino MB that has better design structure. The best result of the simulation that has been done to the clutch disc with interval 5 mm reduction is owned by clutch disc with 35 mm groove�s length reduction and the value is 121.1 MPa

    Addressing homophobia in three secondary schools in South London

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    Schools have a responsibility to prevent all forms of bullying, including that related to\ud sexual orientation. However, to date relatively little is known about how schools are\ud successfully tackling homophobia and homophobic bullying. The aim of this study\ud therefore was to generate new knowledge about how three secondary schools in\ud South London, England, were engaging with and addressing homophobia.\ud A coeducational, a boys' and a girls' school were selected — each having conducted\ud work to counter homophobic bullying. In each school, individual interviews were\ud conducted with three members of staff and group interviews were conducted with\ud pupils drawn from two Year groups (from Year 9, 10 or 11). Information was also\ud drawn from the schools' latest Ofsted report. Interviews were audio-recorded,\ud transcribed and data analysed thematically by way of successive approximation.\ud Work on homophobia and homophobic bullying was said by staff to be part of the\ud commitment by schools to counter bullying in all its forms, to extend equal\ud opportunities and to promote an inclusive whole school ethos. This they did through\ud policy development, continuing professional development and, in particular, through\ud Personal Social and Health Education and Citizenship. However, more needed to be\ud done in each school to ensure that all staff were competent to address homophobia.\ud Pupils stated that they were keen that homophobic bullying should be tackled in their\ud school — although some noted that they would find it difficult, themselves, to take an\ud anti-homophobic stance. Pupils stated that work carried out in schools had some\ud influence on them — although as important was personal contact with lesbians and gay\ud men and the media.\ud Findings are discussed in relation to the utilisation of national policies and\ud programmes, school improvement through preventing homophobia, extending Sex\ud and Relationship Education, and teaching about same-sex sexuality as a noncontroversial\ud issue. Implications for my own professional practice are outlined

    An Abundance of Riches: Cross-Task Comparisons of Semantic Richness Effects in Visual Word Recognition

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    There is considerable evidence (e.g., Pexman et al., 2008) that semantically rich words, which are associated with relatively more semantic information, are recognized faster across different lexical processing tasks. The present study extends this earlier work by providing the most comprehensive evaluation to date of semantic richness effects on visual word recognition performance. Specifically, using mixed effects analyses to control for the influence of correlated lexical variables, we considered the impact of number of features, number of senses, semantic neighborhood density, imageability, and body–object interaction across five visual word recognition tasks: standard lexical decision, go/no-go lexical decision, speeded pronunciation, progressive demasking, and semantic classification. Semantic richness effects could be reliably detected in all tasks of lexical processing, indicating that semantic representations, particularly their imaginal and featural aspects, play a fundamental role in visual word recognition. However, there was also evidence that the strength of certain richness effects could be flexibly and adaptively modulated by task demands, consistent with an intriguing interplay between task-specific mechanisms and differentiated semantic processing

    Pattern scaling using ClimGen: monthly-resolution future climate scenarios including changes in the variability of precipitation

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    Development, testing and example applications of the pattern-scaling approach for generating future climate change projections are reported here, with a focus on a particular software application called “ClimGen”. A number of innovations have been implemented, including using exponential and logistic functions of global-mean temperature to represent changes in local precipitation and cloud cover, and interpolation from climate model grids to a finer grid while taking into account land-sea contrasts in the climate change patterns. Of particular significance is a new approach for incorporating changes in the inter-annual variability of monthly precipitation simulated by climate models. This is achieved by diagnosing simulated changes in the shape of the gamma distribution of monthly precipitation totals, applying the pattern-scaling approach to estimate changes in the shape parameter under a future scenario, and then perturbing sequences of observed precipitation anomalies so that their distribution changes according to the projected change in the shape parameter. The approach cannot represent changes to the structure of climate timeseries (e.g. changed autocorrelation or teleconnection patterns) were they to occur, but is shown here to be more successful at representing changes in low precipitation extremes than previous pattern-scaling methods

    Incidence of first stroke and ethnic differences in stroke pattern in Bradford, UK: Bradford Stroke Study

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    Background: Information on ethnic disparities in stroke between White and Pakistani population in Europe is scarce. Bradford District has the largest proportion of Pakistani people in England; this provides a unique opportunity to study the difference in stroke between the two major ethnic groups. Aim: To determine the first-ever-stroke incidence and examine the disparities in stroke patterns between Whites and Pakistanis in Bradford. Methods: Prospective 12 months study consisting of 273,327 adults (≥18 years) residents. Stroke cases were identified by multiple overlapping approaches. Results: In the study period, 541 first-ever-strokes were recorded. The crude incidence rate was 198 per 100,000 person-years. Age adjusted-standardized rate to the World Health Organization world population of first-ever-stroke is 155 and 101 per 100,000 person-years in Pakistanis and Whites respectively. Four hundred and thirty-eight patients (81%) were Whites, 83 (15.3%) were Pakistanis, 11 (2%) were Indian and Bangladeshis, and 9 (1.7%) were of other ethnic origin. Pakistanis were significantly younger and had more obesity (p = 0.049), and diabetes mellitus (DM) (p = <0.001). They were less likely to suffer from atrial fibrillation (p = <0.001), be ex- or current smokers (p = <0.001), and drink alcohol above the recommended level (p = 0.007) compared with Whites. In comparison with Whites, higher rates of age-adjusted stroke (1.5-fold), lacunar infarction (threefold), and ischemic infarction due to large artery disease (twofold) were found in the Pakistanis. Conclusions: The incidence of first-ever-stroke is higher in the Pakistanis compared with the Whites in Bradford, UK. Etiology and vascular risk factors vary between the ethnic groups. This information should be considered when investigating stroke etiology, and when planning prevention and care provision to improve outcomes after stroke

    Simulations of idealised 3D atmospheric flows on terrestrial planets using LFRic-Atmosphere

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    We demonstrate that LFRic-Atmosphere, a model built using the Met Office's GungHo dynamical core, is able to reproduce idealised large-scale atmospheric circulation patterns specified by several widely-used benchmark recipes. This is motivated by the rapid rate of exoplanet discovery and the ever-growing need for numerical modelling and characterisation of their atmospheres. Here we present LFRic-Atmosphere's results for the idealised tests imitating circulation regimes commonly used in the exoplanet modelling community. The benchmarks include three analytic forcing cases: the standard Held-Suarez test, the Menou-Rauscher Earth-like test, and the Merlis-Schneider Tidally Locked Earth test. Qualitatively, LFRic-Atmosphere agrees well with other numerical models and shows excellent conservation properties in terms of total mass, angular momentum and kinetic energy. We then use LFRic-Atmosphere with a more realistic representation of physical processes (radiation, subgrid-scale mixing, convection, clouds) by configuring it for the four TRAPPIST-1 Habitable Atmosphere Intercomparison (THAI) scenarios. This is the first application of LFRic-Atmosphere to a possible climate of a confirmed terrestrial exoplanet. LFRic-Atmosphere reproduces the THAI scenarios within the spread of the existing models across a range of key climatic variables. Our work shows that LFRic-Atmosphere performs well in the seven benchmark tests for terrestrial atmospheres, justifying its use in future exoplanet climate studies.Comment: 34 pages, 9(12) figures; Submitted to Geoscientific Model Development; Comments are welcome (see Discussion tab on the journal's website: https://egusphere.copernicus.org/preprints/2023/egusphere-2023-647
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