Contracts and production

It is argued that a change in the prevailing theory of production is also influencing how contracts, especially in construction, are being conceived. It is contended that the theoretical shift in question, both in production and contracting, concerns the metaphysical presuppositions of respective theories. This claim is further justified through a critical analysis of how risks and collaboration between parties are considered in conventional contracting

Selective extraction of heavy metals in bottom sediments from Tietê River, São Paulo

Sediment samples from Tietê river were submitted to chemical and sequential extractions of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn). It was followed a single extraction by using 0.1 mol L-1 hydrochloric acid and a sequential procedure to evaluate possible chemical associations described as exchangeable, carbonate, reducible oxides, sulfide, organic matter and residual fractions. High concentrations of heavy metals were determined at Pirapora reservoir, which is closer to the Metropolitan Area of São Paulo while for Barra Bonita reservoir, the results showed low concentrations for such elements. Acid volatile sulfides, grain size distribution and carbon contents were also determined.CNP

Target value design: using collaboration and a lean approach to reduce construction cost

Target Costing is an effective management technique that has been used in manufacturing for decades to achieve cost predictability during new products development. Adoption of this technique promises benefits for the construction industry as it struggles to raise the number of successful outcomes and certainty of project delivery in terms of cost, quality and time. Target Value Design is a management approach that takes the best features of Target Costing and adapts them to the peculiarities of construction. In this paper the concept of Target Value Design is introduced based on the results of action research carried out on 12 construction projects in the USA. It has been shown that systemic application of Target Value Design leads to significant improvement of project performance – the final cost of projects was on average 15% less than market cost. The construction industry already has approaches that have similarities with elements of the Target Value Design process or uses the same terminology, e.g. Partnering and Target Cost Contracts, Cost planning, etc. Following an exploration of the similarities and differences Target Value Design is positioned as a form of Target Costing for construction that offers a more reliable route to successful projects outcomes

Assessment of self-representation abilities in seven-eight year old children

TEMA: Teoria da Mente. OBJETIVO: o objetivo deste estudo foi verificar os aspectos metarrepresentacionais em crianças de 7 a 8 anos e investigar as relações entre linguagem e Teoria da Mente. MÉTODO: participaram da pesquisa 100 crianças - 50 meninos e 50 meninas - com idades entre 7:2 e 8:11, divididas em quatro grupos: crianças de sete anos sem alterações comunicativas (Grupo1), compostas por 37 sujeitos; crianças de sete anos com atraso fonológico (Grupo 2), composto por 13 sujeitos; crianças de oito anos sem alterações comunicativas (Grupo 3), composto por 46 sujeitos; e, crianças de oito anos com atraso fonológico (Grupo 4), composto por 4 sujeitos. Todos os sujeitos são alunos de uma escola municipal localizada na região metropolitana de São Paulo e passaram por triagens de fala, linguagem e audição, além da avaliação da metarrepresentação, que é composta por quatro testes. Utilizou-se para a avaliação da metarrepresentação a prova de Teoria da Mente proposta por Fernandes (2002) e adaptada por Mecca (2005). RESULTADOS: entre os sujeitos de sete anos, 88% passaram na avaliação da metarrepresentação. Entre os sujeitos de oito anos, este índice foi de 92%. Não foram encontradas diferenças significantes por sexo, idade ou grupo. CONCLUSÃO: em torno dos sete anos de idade a grande maioria das crianças adquiriu a Teoria da Mente, embora esta aquisição possa se estender além desta. A forma de interação e a presença de elementos abstratos durante a conversação podem influenciar o desempenho das crianças nas tarefas de Teoria da Mente.BACKGROUND: Theory of Mind. AIM: the purpose of this study was to assess the self-representation abilities in 7-8 year old children and to verify the relationship between the Theory of Mind and language. METHOD: subjects of this study were 100 children - 50 boys and 50 girls - with ages between 7:2 and 8:11, divided in four groups: 7-year-old children with no communication deficits (Group 1), with 37 subjects; 7-year-old children with phonological retard (Group 2), with 13 subjects; 8-year-old children with no communication deficits (Group 3), with 46 subjects; and 8- year- old children with phonological retard (Group 4), with 4 subjects. All of the subjects were students of a municipal school in the city of São Paulo and were submitted to speech, language and hearing tests prior to the assessment of the self-representation abilities. The assessment of the self-representation abilities is composed by four tests proposed by Fernandes (2002) and adapted by Mecca (2005). RESULTS: 88% of the 7-year-old subjects passed the self-representation abilities test; 92% of the 8-year-old subjects also passed the same test. No statistically significant differences were found between gender, age or group. CONCLUSION: generally, children around 7 years have already acquired the Theory of Mind, however this acquisition can take longer and occur at other ages. The type of interaction and the presence of abstract elements during conversation can have an influence on the children's performance in tasks involving the theory of mind

Exact solution of Kerr black hole perturbations via CFT2 and instanton counting: Greybody factor, quasinormal modes, and Love numbers

We give explicit expressions for the finite frequency greybody factor, quasinormal modes, and Love numbers of Kerr black holes by computing the exact connection coefficients of the radial and angular parts of the Teukolsky equation. This is obtained by solving the connection problem of the confluent Heun equation in terms of the explicit expression of irregular Virasoro conformal blocks as sums over partitions via the Alday, Gaiotto, and Tachikawa correspondence. In the relevant approximation limits our results are in agreement with existing literature. The method we use can be extended to solve the linearized Einstein equation in other interesting gravitational backgrounds

Global atmospheric distribution of microplastics with evidence of low oceanic emissions

Recent investigations based on sea–air transfer physical mechanistic studies suggest that the global ocean’s contribution to atmospheric microplastic emissions is significantly lower (four orders of magnitude) than previously estimated. However, no atmospheric models or observations have yet validated this lower emission flux, leaving the analysis without adequate validation and practical significance. Here, we provide quantitative estimates of the global atmospheric microplastic budget based on this reduced oceanic flux. Our model aligns well with observed atmospheric microplastic concentrations and suggests that the ocean functions more as a sink than a source, contributing only ~0.008% of global emissions but accounting for ~15% of total deposition. This challenges the previous view of the ocean as the primary atmospheric microplastic source, urging a reassessment of pollution mitigation strategies

Holographic thermal correlators from supersymmetric instantons

We present an exact formula for the thermal scalar two-point function in four-dimensional holographic conformal field theories. The problem of finding it reduces to the analysis of the wave equation on the AdS-Schwarzschild background. The two-point function is computed from the connection coefficients of the Heun equation, which can be expressed in terms of the Nekrasov-Shatashvili partition function of an SU(2) supersymmetric gauge theory with four fundamental hypermultiplets. The result is amenable to numerical evaluation upon truncating the number of instantons in the convergent expansion of the partition function. We also examine it analytically in various limits. At large spin the instanton expansion of the thermal two-point function directly maps to the light-cone bootstrap analysis of the heavy-light four-point function. Using this connection, we compute the OPE data of heavy-light double-twist operators. We compare our prediction to the perturbative results available in the literature and find perfect agreement.Comment: 9 pages + appendices, 2 figures. v2: typos corrected, references adde