A simple two-module problem to exemplify building-block assembly under crossover

Theoretically and empirically it is clear that a genetic algorithm with crossover will outperform a genetic algorithm without crossover in some fitness landscapes, and vice versa in other landscapes. Despite an extensive literature on the subject, and recent proofs of a principled distinction in the abilities of crossover and non-crossover algorithms for a particular theoretical landscape, building general intuitions about when and why crossover performs well when it does is a different matter. In particular, the proposal that crossover might enable the assembly of good building-blocks has been difficult to verify despite many attempts at idealized building-block landscapes. Here we show the first example of a two-module problem that shows a principled advantage for cross-over. This allows us to understand building-block assembly under crossover quite straightforwardly and build intuition about more general landscape classes favoring crossover or disfavoring it

O formoterol e uma dose média/ elevada de corticosteróides inalados são mais eficazes do que uma dose elevada de corticosteróides na asma moderada e grave

RESUMO: As normas internacionais para o tratamento da asma brônquica recomendam que os doentes com sintomatologia mal controlada com doses baixas/ /intermédias de corticosteróides (CT) inalados sejam submetidos a doses mais elevadas de CT e, se necessário, deverá ser adicionado um β2 agonista de longa duração. No entanto, estudos mais recentes demonstraram que a adição deste fármaco a doses baixas/moderadas de CT inalados permite um melhor controlo da sintomatologia do que a duplicação da dose de CT. O formoterol constitui o β2 agonista de eleição devido ao seu início de acção rápida.O objectivo do presente trabalho foi comparar a eficácia da associação do β2 agonista formoterol a doses médias/elevadas de CT inalados com a duplicação da dose do CT em indivíduos com asma moderada/grave mal controlada.Foram avaliados doentes com idade superior a 18 anos com asma moderada e grave que apresentavam um FEV1â¥50% do previsto e um aumentoâ¥15% do referido parâmetro após inalação de um broncodilatador de curta duração, tendo sido submetido a terapêutica com CT inalados diariamente (dipropionato de beclometasona 1000 μ - budesonida 800 μg) no mês que precedeu o início do estudo em análise. A existência de, pelo menos, dois dos parâmetros seguintes, nos últimos 7 dias do período de run-in, foi imprescindível: sintomatologia interferindo com as actividades de vida diária; interrupção do sono por sintomas nocturnos, necessidade de terapêutica de alívio numa doseâ¥4 puffs salbutamol/dia; variabilidade diária do PEF (Peak Expiratory Flow)â¥15%.Foram critérios de exclusão: doentes cuja dose do CT inalado diária foi alterada no último mês; indivíduos submetidos a CT oral ou β2 agonista de longa duração no mês precedente; doentes com dificuldade de utilizar o aerolizer apesar da instrução adequada.Tratou-se de um estudo randomizado, duplamente cego, envolvendo 203 indivíduos: 102 submetidos a formoterol 12 μg e dipropionato de beclometasona 500 μg duas vezes/dia; 101 sob este corticosteróide na dose de 1000 μg duas vezes/dia e placebo. Ambos os grupos foram tratados com os referidos fármacos durante 12 semanas. Os doentes estudados apresentavam um FEV1 72% do previsto, uma reversibilidade desencadeada pelo (β2 agonista de curta duração de 27%, scores de sintomas moderados e necessidade de terapêutica de alívio na doseâ¥5 puffs de salbutamol/ dia.A diferença do PEF entre os dois grupos foi de 27,78 1/minuto, sendo favorável à associação formoterol/beclometasona (p=0,0002). Foi observada, também, uma diferença estatisticamente significativa na relação cortisol/ creatinina urinário após o tratamento de 12 semanas (p=0,001), indicando supressão do eixo hipotalâmico-hipofisário nos doentes sob 1000 μg de dipropionato de beclometasona duas vezes/ dia. Os scores de sintomas foram significativamente mais baixos nos doentes sob terapêutica combinada, sendo a proporção de doentes livres de sintomas durante o dia duas vezes superior neste grupo e a utilização de terapêutica de alívio inferior. COMENTÃRIO: Este estudo demonstra que, no tratamento de doentes com asma moderada/grave não controlada com dipropionato de beclometasona 1000 μg/dia, a adição de formoterol 12 μg duas vezes/dia é mais eficaz do que a duplicação da dose de beclometasona.A terapêutica combinada melhora significativamente os parâmetros objectivos da obstrução das vias aéreas quando comparada com altas doses de corticosteróides inalados. O efeito benéfico de adição de formoterol na função pulmonar tornou-se evidente após quatro semanas de tratamento e permaneceu inalterada até ao fim do estudo. Este efeito pode dever-se ao antagonismo funcional do formoterol à contracção do músculo liso, à sua capacidade de estabilizar os mastócitos ou de reduzir o edema da parede brônquica.As exacerbações ligeiras e moderadas ocorreram com maior frequência no grupo sob altas doses de CT inalados. Estes resultados foram sobreponíveis aos observados anteriormente em doentes com asma ligeira submetidos à associação formoterol/budesonido (dose baixa/intermédia) ou a doses elevadas deste último fármaco. Também neste estudo se verificou um maior número de exacerbações no segundo grupo.Elevadas doses de CT inalados estão relacionadas com significativos efeitos suprarrenais. Assim, a associação de um β2 agonista de longa acção (formoterol) permite o controlo da doença sem necessidade de doses altas de CT inalados. Neste estudo, o quociente cortisol/creatinina urinário foi significativamente menor no grupo sob corticoterapia em dose elevada do que nos indivíduos submetidos a terapêutica combinada, traduzindo uma maior supressão do risco hipotalâmico-hipofisário no primeiro caso. Estes achados vieram confirmar a observação de que o dipropionato de beclometasona na doseâ¥1500 μg/dia exerce um efeito supressor significativo na libertação de cortisol endógeno.A terapêutica combinada de CT inalados e β2 agonistas de longa acção permitiu um bom controlo da asma brônquica, comparativamente a baixas doses de CT, e conduziu à administração dos fármacos inalados em doses fixas através de um dispositivo único. Ringdal e colaboradores compararam a eficácia do salmeterol 50 μg/ fluticasona 250 μg utilizando Diskus duas vezes/dia com o formoterol 12 μg/ budesonido 500 μg administrados separadamente através do Turbohaler duas vezes/ /dia. A primeira associação foi significativamente superior na redução das exacerbações de asma e dos sintomas nocturnos, apesar da dose mais baixa de fluticasona comparada com a de budesonido. Estes resultados não são, no entanto, inesperados, visto a fluticasona ser mais potente do que o budesonido.Apesar de a administração de fármacos em doses fixas num único dispositivo ter vantagens adicionais em termos de aderência ao tratamento e conveniência, não apresenta grande flexibilidade no ajuste da dose durante as exacerbações. São, assim, necessários novos estudos para avaliar os dispositivos mais apropriados, de forma a obter o maior sinergismo de acção entre β2 agonista de longa duração e os CT inalados. Palavras-chave: Asma moderada/grave, β2 agonista de longa acção, formoterol, corticosteróides inalados, beclometason

Towards Normalizing the Edit Distance Using a Genetic Algorithms Based Scheme

The normalized edit distance is one of the distances derived from the edit distance. It is useful in some applications because it takes into account the lengths of the two strings compared. The normalized edit distance is not defined in terms of edit operations but rather in terms of the edit path. In this paper we propose a new derivative of the edit distance that also takes into consideration the lengths of the two strings, but the new distance is related directly to the edit distance. The particularity of the new distance is that it uses the genetic algorithms to set the values of the parameters it uses. We conduct experiments to test the new distance and we obtain promising results.Comment: The 8th International Conference on Advanced Data Mining and Applications (ADMA 2012

Assessment of atmospheric aerosols from two reanalysis products over Australia

Assessments of atmospheric aerosols from reanalysis are important for understanding uncertainty in model simulations, and ultimately predictions, such as for solar power or air quality forecasts and assessments. This study intercompares total aerosol optical depth (AOD) and dust AOD (DAOD) from two global reanalyses datasets, the European Centre for Medium-Range Weather Forecasts (ECMWF) Monitoring Atmospheric Composition and Climate (MACC) and the NASA Modern-Era Retrospective Analysis for Research-2 (MERRA-2). These are evaluated against AeroSpan (Aerosol characterisation via Sun photometry: Australian Network) ground observations which forms part of the Aerosol Robotic Network (AERONET) over the Australian continent for the 2002–2012 period. During dust storms, AeroSpan/AERONET AOD measurements were missing due to cloud screening. To overcome validation limitations in sun photometry for dust events, a nephelometer's scattering coefficient is qualitatively compared against reanalysis of DAOD at a key dust storm activation site, Tinga Tingana in South Australia (~200 km east of Lake Eyre). A specific extreme event that occurred in 2009 originating from the Lake Eyre basin, a major dust source covering one-sixth of Australia, was studied. The results show that MERRA-2 reanalysis overestimates monthly total AOD twice as much compared to AeroSpan/AERONET ground observations but seems better correlated against AeroSpan/AERONET than ECMWF/MACC. Mean data of MERRA-2 time series over 10 years provide lower DAOD values and lower dust aerosol estimates than ECMWF/MACC reanalysis (over the Lake Eyre basin with spatial averaging). Specifically at Tinga Tingana, the correlation from MERRA-2 (0.45 correlation) and ECMWF/MACC (0.43 correlation) against AeroSpan/AERONET's AOD were similar. Between MERRA-2 and ECMWF/MACC decade long daily gridded DAOD, the correlation coefficient was high at 0.73, again indicating similarity between the datasets. MERRA-2 total AOD correlation is significantly higher (by 0.26) against AeroSpan/AERONET than ECMWF/MACC. MERRA-2 also provides higher AOD values in extreme cases which may correspond to dust storms. During dust storms, a hybrid strategy using nephelometers and hourly reanalysis from MERRA-2 is able to identify dust storms better than AeroSpan/AERONET. Overall, this work can enable and inform better aerosol data assimilation into forecast models such as for solar energy, agriculture or air quality over Australia

A study of cultivation and sowing systems for cereals.

End of Project ReportDue to the pressure on cereal margins growers are seeking ways of reducing their costs of production. Reduced cultivation may provide cheaper and faster crop establishment, but in the past has been subject to problems with (poor crop establishment) weeds and soil compaction. With modern cultivation and sowing technology and methodology it may be possible to overcome these difficulties. In addition reduced cultivation is considered to be more environmentally friendly and sustainable than the conventional plough-based system. With these considerations in mind it was decided to start an experiment in autumn 2000 to compare the conventional system (PL) with reduced cultivation (RC) for crop establishment, and to examine the effect of incorporating the straw into then soil or baling and removing it. The treatments were assessed on winter wheat, and winter and spring barley. The parameters assessed included – crop establishment, yield and quality effects on disease levels, invertebrate pests and beneficials (aphids, slugs, earthworms, beetles), and soil conditions. The work reported here was conducted on four trial sites at Oak Park, Carlow and Knockbeg, Co. Laois from 2000 to 2003. the objectives were to establish the efficacy of RC compared with PL and to its effects on the parameters outlined above. Plant establishment was lower after RC in most of the experiments. Winter wheat yields were good irrespective of the number of plants established and there were no significant differences between cultivation or straw disposal method. The relative yields of the PL and RC treatments in winter barley varied over the three years; in 2001 there was no difference, in 2002 PL yielded 1 t/ha more than RC, while in 2003 the PL area produced 2 t/ha extra. Spring barley yields were similar on the PL and RC treatments. Broadleaved weeds were not a problem on the PL or RC treatments but there were more annual grass weeds on the RC plots. This was particularly serious in the winter barley experiments where sterile brome (Bromus sterilis) had a big effect on yield by 2003. annual meadow grass (Poa annua) was a problem in both PL and RC areas if not controlled by timely herbicide application; this was particularly so on the headland areas in the spring barley field. Disease assessment on the winter wheat trail showed no significant differences in Take-all or Eyespot levels between cultivation or straw disposal methods, although Take-all levels tended to be lower on the RC plots. Soil strength as measured by cone penetrometer and shear vane was higher on the RC treatments. In the winter wheat there was no difference in slug numbers between any of the treatments. Leaf damage by slugs increased in RC relative to PL but not significantly, in 2003. No below ground slug damage was found. Earthworm numbers in the winter barley increased significantly on the RC treatment relative to the PL as the study progressed. Straw incorporation increased earthworm numbers on both PL and RC treatments. Allolobophora chlorotia was the most common species in 2004. In the winter wheat the RC and straw incorporation increased earthworm numbers. Cultivation method had a greater effect on ground beetle numbers than method of straw disposal. Large species (e.g. Pterostichies malanarius) were favoured by RC while smaller species (e.g. Bembidon species) were more numerous in the PL plots. Molecular studies on virus diseases, vectors and vector-predators are underway in progress. In the invertebrate pests and beneficials investigations the RC winter barley had 11% fewer aphids and 27% less BYDV than the PL. Incorporating straw reduced aphid numbers and virus incidence by 36% and 32% respectively; the comparable values for the PL + straw treatment were 15% and 15%. In the winter wheat there was less BYDV in the RC plots than the PL + less were the straw was incorporated than where the straw was removed. Aphid infestation of wheat ears was low in the three years of the experiment. The insecticide seed treatment imidacloprid significantly reduced aphid numbers and virus incidence in winter barley but was less effective than a single insecticide spray in controlling the disease. The seed treatment was more effective in controlling BYDV in RC than in the PL plots. Estimations of slug numbers in the winter barley showed that the dominant species was the grey field slug (Deroceras reticulatum). Slug numbers increased significantly on all treatments between 2001 and 2004. In November 2004, slugs were significantly more numerous in the RC treatments than in the PL areas. Leaf damage was proportional to slug populations, but the slugs did not damage the barely seed or reduce plant populations in continuous winter barley under RC. Root and stem diseases (Take-all and Eyespot) were not nay worse under RC than after PL. In fact there was a tendency towards lower disease levels on the RC areas and there was significantly less sharp eyespot on the RC treatment

Issues and Opportunities in Exotic Hadrons

The last few years have been witness to a proliferation of new results concerning heavy exotic hadrons. Experimentally, many new signals have been discovered that could be pointing towards the existence of tetraquarks, pentaquarks, and other exotic configurations of quarks and gluons. Theoretically, advances in lattice field theory techniques place us at the cusp of understanding complex coupled-channel phenomena, modelling grows more sophisticated, and effective field theories are being applied to an ever greater range of situations. It is thus an opportune time to evaluate the status of the field. In the following, a series of high priority experimental and theoretical issues concerning heavy exotic hadrons is presented

Sub-clinical assessment of atopic dermatitis severity using angiographic optical coherence tomography

Measurement of sub-clinical atopic dermatitis (AD) is important for determining how long therapies should be continued after clinical clearance of visible AD lesions. An important biomarker of sub-clinical AD is epidermal hypertrophy, the structural measures of which often make optical coherence tomography (OCT) challenging due to the lack of a clearly delineated dermal-epidermal junction in AD patients. Alternatively, angiographic OCT measurements of vascular depth and morphology may represent a robust biomarker for quantifying the severity of clinical and sub-clinical AD. To investigate this, angiographic data sets were acquired from 32 patients with a range of AD severities. Deeper vascular layers within skin were found to correlate with increasing clinical severity. Furthermore, for AD patients exhibiting no clinical symptoms, the superficial plexus depth was found to be significantly deeper than healthy patients at both the elbow (p = 0.04) and knee (p < 0.001), suggesting that sub-clinical changes in severity can be detected. Furthermore, the morphology of vessels appeared altered in patients with severe AD, with significantly different vessel diameter, length, density and fractal dimension. These metrics provide valuable insight into the sub-clinical severity of the condition, allowing the effects of treatments to be monitored past the point of clinical remission

The visual sociogram in qualitative and mixed-methods research

The paper investigates the place of visual tools in mixed-methods research on social networks, arguing that they can not only improve the communicability of results, but also support research at the data gathering and analysis stages. Three examples from the authors’ own research experience illustrate how sociograms can be integrated in multiple ways with other analytical tools, both quantitative and qualitative, positioning visualization at the intersection of varied methods and channelling substantive ideas as well as network insight in a coherent way. Visualization also facilitates the participation of a broad range of stakeholders, including among others, study participants and non-specialist researchers. It can support the capacity of qualitative and mixed-methods research to reach out to areas of the social that are difficult to circumscribe, such as hidden populations and informal organisations. On this basis, visualization appears as a unique opportunity for mixing methods in the study of social networks, emphasizing both structure and process at the same time

DT fusion neutron radiation strengthening of copper and niobium

The initial results of a comparative study of the radiation strengthening and damage structures produced in Cu and Nb by D-T fusion and fission reactor neutrons are described. The radiation strengthening produced by a given fluence of fusion neutrons above about 10$sup 17$n/cm$sup 2$ is equal to that produced by a fluence of fission reactor neutrons (E greater than 0.1 MeV) ten times as great. This difference is about twice as large as would be expected if the strengthening scaled with damage energy or dpa. Initial transmission electron microscopy observations of the damage structures in fusion and fission reactor neutron irradiated copper indicate that the same type of primary structural defects, vacancy and interstitial point defect clusters and small dislocation loops with a/3 (111) and a/2 (110) Burgers vectors, are produced in both cases. The difference in the radiation strengthening produced by fusion and fission reactor neutrons in Cu appears to result from a substantially greater rate of accumulation of damage, in the form of point defect clusters, during irradiation with fusion neutrons than during irradiation with fission reactor neutrons plus a significant difference in the size and spatial distributions of the damage clusters. (auth