Widom line prediction by the Soave-Redlich-Kwong and Peng-Robinson equations of state

Using cubic equations of state for a single-component fluid, we compute pseudocritical loci where the isobaric heat capacity is a relative maximum at constant pressure, or at constant temperature. These two loci, called the Widom line and the characteristic isobaric inflection curve (CIIC), are quite different from each other, as we show using the van der Waals equation, based on which the two loci admit a closed-form representation in the (P, T) plane. Similarly, the Redlichâ Kwong (RK) equation leads to a closed-form representation for the CIIC in the (T,v) plane. With the Soaveâ Redlichâ Kwong (SRK) and the Pengâ Robinson (PR) equations we find almost coincident predictions for the above-mentioned pseudocritical loci; furthermore, comparing our results with a correlation obtained by regression of experimental data for CO2and water shows that the increased complexity of the SRK and PR equations (as compared to RK) allows improved agreement with the experimental data

Prospective associations between dietary patterns and cognitive performance during adolescence

Background: The aim of the study was to investigate prospective associations between dietary patterns and cognitive performance during adolescence .Methods: Participants were sourced from the Western Australian Pregnancy Cohort (Raine) Study that includes 2868 children born between 1989 and 1992 in Perth, Western Australia. When the children were 17 years old (2006–2009), cognitive performance was assessed using a computerized cognitive battery of tests (CogState) that included six tasks. Using a food frequency questionnaire administered when the children were 14 years old (2003–2006), ‘Healthy’ and ‘Western’ dietary patterns were identified by factor analysis. Associations between dietary patterns at 14 years of age and cognitive performance at 17 years of age were assessed prospectively using multivariate regression models.Results: Dietary and cognitive performance data were available for 602 participants. Following adjustment for the ‘Healthy’ dietary pattern, total energy intake, maternal education, family income, father's presence in the family, family functioning and gender, we found that a longer reaction time in the detection task (ß = .016; 95% CI: 0.004; 0.028; p = .009) and a higher number of total errors in the Groton Maze Learning Test – delayed recall task (ß = .060; 95% CI: 0.006; 0.114; p = .029) were significantly associated with higher scores on the ‘Western’ dietary pattern. The ‘Western’ dietary pattern was characterized by high intakes of take-away food, red and processed meat, soft drink, fried and refined food. We also found that within the dietary patterns, high intake of fried potato, crisps and red meat had negative associations, while increased fruit and leafy green vegetable intake had positive associations with some aspects of cognitive performance. Conclusion: Higher dietary intake of the ‘Western’ dietary pattern at age 14 is associated with diminished cognitive performance 3 years later, at 17 years

A successful local fluid-to-fluid similarity theory for heat transfer to supercritical pressure fluids: merits and limitations

A similarity theory, proposed with a limited success some years ago and subsequently refined in a more complex form in further efforts, has been applied in a recent published work to perform Direct Numerical Simulations (DNS) of heat transfer to turbulent flow, with four different fluids at supercritical pressure. The obtained results showed an exceptionally good behaviour of the theory in the addressed cases, suggesting that the initial proposal, though it had only limited success in the cases considered at that time, possibly caught some of the basic features to be preserved in scaling. The theory, based on dimensionless definitions that provided a reasonable degree of universality in the analysis of flow stability, found immediate difficulties to be applied with a comparable success to heat transfer problems. These difficulties mainly stemmed from the fact that, while it is relatively easy to scale fluid density, having a major role in stability analyses, it is definitely much harder to scale at a comparable level of accuracy the fluid thermo-physical properties, relevant in heat transfer. The very good results obtained in the recent work by DNS stimulated new reflections that shed light on the merits and limitations on the old theory. The present paper, starting from these recent results and discussing them in front of RANS calculations, is aimed to highlight the promising features of this theory, envisaging the missing steps that should be completed to make it more general, in order to give to its consequences a higher level of universality

Nutritional status, yield and composition of peach fruit subjected to the application of organic compost.

The purpose of this study was to evaluate the nutritional state, yield and composition of peaches on peach trees subjected to the application of organic compost to the soil. This experiment was conducted during the 2008 and 2009 cropping season in an orchard containing Chimarrita cultivars grafted onto Capdeboscq rootstocks and Haplumbrept soils in the municipality of Farroupilha (Rio Grande do Sul State), Brazil. The treatments included 0, 9, 18, 36, 72 and 144 liters of organic compost per plant-1 year-1. The total nutrient contents in the leaves, yield components, yields per plant and hectare and compositions of the fruits were evaluated in 2008 and 2009 soon after harvest and after 30 days of storage. The application of organic compost to the soil increased the yield components and the yields per plant and hectare in the two treatments with the highest compost additions, which indicated that the addition of 72 L of compost per plant-1 is ideal economically. The organic compost had little effect on the composition of the peach fruit after harvest and after 30 days of storage. Keywords: mineral nutrition, organic waste, Prunus persica. Estado nutricional, produção e composição de frutos de pessegueiros submetidos à aplicação de composto orgânico O objetivo do trabalho foi avaliar o estado nutricional, produção e composição de pêssegos em pessegueiros submetidos à aplicação de composto orgânico no solo. O experimento foi conduzido, na safra 2008 e 2009, em um pomar da cultivar Chimarrita, enxertada sobre o porta-enxerto Capdeboscq e cultivadas em um solo Cambissolo Húmico, no município de Farroupilha (Estado do Rio Grande do Sul). Os tratamentos foram 0, 9, 18, 36, 72 e 144 litros de composto orgânico por planta-1 ano-1. Avaliou-se o teor de nutrientes totais nas folhas, componentes de produção, produção por planta e hectare e a composição dos frutos em 2008 e 2009, logo depois da colheita e 30 dias após armazenamento. A aplicação de composto orgânico no solo, aumenta os valores de componentes de produção e a produção de pêssego por planta e hectare, nas duas maiores quantidades de composto fornecidas, o que economicamente indica a melhor dose de 72 L de composto por planta-1. A adição de composto orgânico na superfície do solo não afeta o estado nutricional e pouco afeta a composição dos pêssegos após a colheita e depois de 30 dias do armazenamento. Palavras-chave: nutrição mineral, resíduos orgânicos, Prunus persica

SCWR ROD BUNDLE THERMAL ANALYSIS BY A CFD CODE

ABSTRACT The present paper describes the results of the application of the FLUENT code in the analysis of rod bundle configurations proposed for high pressure supercritical water reactors. The model considers a 1/8 slice of a rod bundle. The details from CFD calculations offer predictions of the circumferential clad surface temperature and of the effect of axial power distribution on the mass exchange between subchannels and on the maximum surface rod temperature. Geometry and boundary conditions are adopted from a previous work that made use of subchannel programs, allowing for a direct comparison between the two techniques. Both the standard k-ε model and the Reynolds stress transport model are used. Conclusions are drawn about the present capabilities in predicting heat transfer behavior in fuel rod bundles proposed for supercritical water reactors

The association between dietary patterns and mental health in early adolescence

Objective: To investigate the associations between dietary patterns and mental health in early adolescence. Method: The Western Australian Pregnancy Cohort (Raine) Study is a prospective study of 2900 pregnancies recruited from 1989-1992. At 14 years of age (2003-2006; n = 1324), the Child Behaviour Checklist (CBCL) was used to assess behaviour (characterising mental health status), with higher scores representing poorer behaviour. Two dietary patterns (Western and Healthy) were identified using factor analysis and food group intakes estimated by a 212-item food frequency questionnaire. Relationships between dietary patterns, food group intakes and behaviour were examined using general linear modelling following adjustment for potential confounding factors at age 14: total energy intake, body mass index, physical activity, screen use, family structure, income and functioning, gender and maternal education at pregnancy. Results: Higher total (b = 2.20, 95% CI = 1.06, 3.35), internalizing (withdrawn/depressed) (b = 1.25, 95% CI = 0.15, 2.35) and externalizing (delinquent/aggressive) (b = 2.60, 95% CI = 1.51, 3.68) CBCL scores were significantly associated with the Western dietary pattern, with increased intakes of takeaway foods, confectionary and red meat. Improved behavioural scores were significantly associated with higher intakes of leafy green vegetables and fresh fruit (components of the Healthy pattern). Conclusion: These findings implicate a Western dietary pattern in poorer behavioural outcomes for adolescents. Better behavioural outcomes were associated with a higher intake of fresh fruit and leafy green vegetables

Colonização micorrízica e crescimento da videira (Vitis vinifera, Porta-Enxerto P1103) em solo com alto teor de cobre.

A aplicação de fungicidas cúpricos em vinhedos aumenta o teor de Cu no solo, potencializando a toxidez para a videira. Entretanto, tem sido relatado que os fungos micorrízicos arbusculares (FMA) podem propiciar efeito protetor às plantas em solos contendo excesso de metais pesados. O trabalho objetivou avaliar a colonização micorrízica e o crescimento da videira (porta-enxerto P1103) em solo contendo elevados teores de Cu. Avaliou-se seis tratamentos de inoculação com FMA (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus e R. irregularis), além de um não inoculado. Verificou-se que a colonização micorrízica da videira foi elevada (média de 33%), mesmo em solo contendo excesso de Cu. A inoculação dos isolados de FMA testados pouco influenciou o crescimento da videira, mas a inoculação com R. irregulares e R. clarus beneficiou a produção de massa seca das raízes das mudas.Resumo expandido

Acúmulo de fósforo em solos cultivados com videiras na região da Campanha Gaúcha.

O presente trabalho teve como objetivo avaliar o acúmulo de frações de P em solos cultivados com videiras e com histórico de aplicação de fertilizantes fosfatados na região da Campanha Gaúcha do RS.bitstream/item/73780/1/Comunicado-Tecnico-131.pd

Feedback control of arm movements using Neuro-Muscular Electrical Stimulation (NMES) combined with a lockable, passive exoskeleton for gravity compensation.

Within the European project MUNDUS, an assistive framework was developed for the support of arm and hand functions during daily life activities in severely impaired people. This contribution aims at designing a feedback control system for Neuro-Muscular Electrical Stimulation (NMES) to enable reaching functions in people with no residual voluntary control of the arm and shoulder due to high level spinal cord injury. NMES is applied to the deltoids and the biceps muscles and integrated with a three degrees of freedom (DoFs) passive exoskeleton, which partially compensates gravitational forces and allows to lock each DOE The user is able to choose the target hand position and to trigger actions using an eyetracker system. The target position is selected by using the eyetracker and determined by a marker-based tracking system using Microsoft Kinect. A central controller, i.e., a finite state machine, issues a sequence of basic movement commands to the real-time arm controller. The NMES control algorithm sequentially controls each joint angle while locking the other DoFs. Daily activities, such as drinking, brushing hair, pushing an alarm button, etc., can be supported by the system. The robust and easily tunable control approach was evaluated with five healthy subjects during a drinking task. Subjects were asked to remain passive and to allow NMES to induce the movements. In all of them, the controller was able to perform the task, and a mean hand positioning error of less than five centimeters was achieved. The average total time duration for moving the hand from a rest position to a drinking cup, for moving the cup to the mouth and back, and for finally returning the arm to the rest position was 71 s