Grey-box radial basis function modelling

A fundamental principle in data modelling is to incorporate available a priori information regarding the underlying data generating mechanism into the modelling process. We adopt this principle and consider grey-box radial basis function (RBF) modelling capable of incorporating prior knowledge. Specifically, we show how to explicitly incorporate the two types of prior knowledge: (i) the underlying data generating mechanism exhibits known symmetric property, and (ii) the underlying process obeys a set of given boundary value constraints. The class of efficient orthogonal least squares regression algorithms can readily be applied without any modification to construct parsimonious grey-box RBF models with enhanced generalisation capability.

Dielectric properties of process cheese from 0.3 to 3 Ghz

Dielectric properties of 16 process cheeses were determined over the frequency range 0.3-3 GHz. The effect of temperature on the dielectric properties of process cheeses were investigated at temperature intervals of 10 degrees C between 5 and 85 degrees C. Results showed that the dielectric constant decreased gradually as frequency increased, for all cheeses. The dielectric loss factor (epsilon") decreased from above 125 to below 12 as frequency increased. epsilon' was highest at 5 degrees C and generally decreased up to a temperature between 55 and 75 degrees C. epsilon" generally increased with increasing temperature for high and medium moisture/fat ratio cheeses. epsilon" decreased with temperature between 5 and 55 degrees C and then increased, for low moisture/fat ratio cheese. Partial least square regression models indicated that epsilon' and epsilon" could be used as a quality control screening application to measure moisture content and inorganic salt content of process cheese, respectively. (c) 2005 Elsevier Ltd. All rights reserved..

Impact of geographical region on urinary metabolomic and plasma fatty acid profiles in subjects with the metabolic syndrome across Europe: the LIPGENE study

The application of metabolomics in multi-centre studies is increasing. The aim of the present study was to assess the effects of geographical location on the metabolic profiles of individuals with the metabolic syndrome. Blood and urine samples were collected from 219 adults from seven European centres participating in the LIPGENE project (Diet, genomics and the metabolic syndrome: an integrated nutrition, agro-food, social and economic analysis). Nutrient intakes, BMI, waist:hip ratio, blood pressure, and plasma glucose, insulin and blood lipid levels were assessed. Plasma fatty acid levels and urine were assessed using a metabolomic technique. The separation of three European geographical groups (NW, northwest; NE, northeast; SW, southwest) was identified using partial least-squares discriminant analysis models for urine (R 2 X: 0•33, Q 2: 0•39) and plasma fatty acid (R 2 X: 0•32, Q 2: 0•60) data. The NW group was characterised by higher levels of urinary hippurate and N-methylnicotinate. The NE group was characterised by higher levels of urinary creatine and citrate and plasma EPA (20 : 5 n-3). The SW group was characterised by higher levels of urinary trimethylamine oxide and lower levels of plasma EPA. The indicators of metabolic health appeared to be consistent across the groups. The SW group had higher intakes of total fat and MUFA compared with both the NW and NE groups (P≤ 0•001). The NE group had higher intakes of fibre and n-3 and n-6 fatty acids compared with both the NW and SW groups (all P< 0•001). It is likely that differences in dietary intakes contributed to the separation of the three groups. Evaluation of geographical factors including diet should be considered in the interpretation of metabolomic data from multi-centre studies.

Comparison of a trained sensory panel and an electronic tongue in the assessment of bitter dairy protein hydrolsates

The bitter taste elicited by dairy protein hydrolysates (DPH) is a renowned issue for their acceptability by consumers and therefore incorporation into foods. The traditional method of assessment of taste in foods is by sensory analysis but this can be problematic due to the overall unpleasantness of the samples. Thus, there is a growing interest into the use of electronic tongues (e-tongues) as an alternative method to quantify the bitterness in such samples. In the present study the response of the e-tongue to the standard bitter agent caffeine and a range of both casein and whey based hydrolysates was compared to that of a trained sensory panel. Partial least square regression (PLS) was employed to compare the response of the e-tongue and the sensory panel. There was strong correlation shown between the two methods in the analysis of caffeine (R2 of 0.98) and DPH samples with R2 values ranging from 0.94-0.99. This study exhibits potential for the e-tongue to be used in bitterness screening in DPHs to reduce the reliance on expensive and time consuming sensory panels.

The impact of social and relational contexts on innovation transfer in foreign subsidiaries

It is widely acknowledged that innovation is one of the pillars of multinational enterprises (MNEs) and that technological knowledge from different host locations is a key factor to the MNEs’ competitive advantages development. Concerning these assumptions, in this paper we aim to understand how the social and the relational contexts affect the conventional and reverse transfer of innovation from MNEs’ subsidiaries hosted in emerging markets. We analyzed the social context through the institutional profile (CIP) level and the relational context through trust and integration levels utilizing a survey sent to 172 foreign subsidiaries located in Brazil, as well as secondary data. Through an ordinary least squares regression (OLS) analysis we found that the relational context affects the conventional and reverse innovation transfer in subsidiaries hosted in emerging markets. We however did not find support for the social context effect.

The CURE scale: a multidimensional measure of service recovery strategy

Purpose – This paper aims to address the gaps in service recovery strategy assessment. An effective service recovery strategy that prevents customer defection after a service failure is a powerful managerial instrument. The literature to date does not present a comprehensive assessment of service recovery strategy. It also lacks a clear picture of the service recovery actions at managers’ disposal in case of failure and the effectiveness of individual strategies on customer outcomes. Design/methodology/approach – Based on service recovery theory, this paper proposes a formative index of service recovery strategy and empirically validates this measure using partial least-squares path modelling with survey data from 437 complainants in the telecommunications industry in Egypt. Findings – The CURE scale (CUstomer REcovery scale) presents evidence of reliability as well as convergent, discriminant and nomological validity. Findings also reveal that problem-solving, speed of response, effort, facilitation and apology are the actions that have an impact on the customer’s satisfaction with service recovery. Practical implications – This new formative index is of potential value in investigating links between strategy and customer evaluations of service by helping managers identify which actions contribute most to changes in the overall service recovery strategy as well as satisfaction with service recovery. Ultimately, the CURE scale facilitates the long-term planning of effective complaint management. Originality/value – This is the first study in the service marketing literature to propose a comprehensive assessment of service recovery strategy and clearly identify the service recovery actions that contribute most to changes in the overall service recovery strategy.

Effect of blending Jersey and Holstein-Friesian milk on Cheddar cheese processing, composition and quality

The aim of this study was to investigate the effects of numerous milk compositional factors on milk coagulation properties using Partial Least Squares (PLS). Milk from herds of Jersey and Holstein- Friesian cattle was collected across the year and blended (n=55), to maximise variation in composition and coagulation. The milk was analysed for casein, protein, fat, titratable acidity, lactose, Ca2+, urea content, micelles size, fat globule size, somatic cell count and pH. Milk coagulation properties were defined as coagulation time, curd firmness and curd firmness rate measured by a controlled strain rheometer. The models derived from PLS had higher predictive power than previous models demonstrating the value of measuring more milk components. In addition to the well-established relationships with casein and protein levels, CMS and fat globule size were found to have as strong impact on all of the three models. The study also found a positive impact of fat on milk coagulation properties and a strong relationship between lactose and curd firmness, and urea and curd firmness rate, all of which warrant further investigation due to current lack of knowledge of the underlying mechanism. These findings demonstrate the importance of using a wider range of milk compositional variables for the prediction of the milk coagulation properties, and hence as indicators of milk suitability for cheese making.

Effects of roads, topography, and land use on forest cover dynamics in the Brazilian Atlantic Forest

Roads and topography can determine patterns of land use and distribution of forest cover, particularly in tropical regions. We evaluated how road density, land use, and topography affected forest fragmentation, deforestation and forest regrowth in a Brazilian Atlantic Forest region near the city of Sao Paulo. We mapped roads and land use/land cover for three years (1962, 1981 and 2000) from historical aerial photographs, and summarized the distribution of roads, land use/land cover and topography within a grid of 94 non-overlapping 100 ha squares. We used generalized least squares regression models for data analysis. Our models showed that forest fragmentation and deforestation depended on topography, land use and road density, whereas forest regrowth depended primarily on land use. However, the relationships between these variables and forest dynamics changed in the two studied periods; land use and slope were the strongest predictors from 1962 to 1981, and past (1962) road density and land use were the strongest predictors for the following period (1981-2000). Roads had the strongest relationship with deforestation and forest fragmentation when the expansions of agriculture and buildings were limited to already deforested areas, and when there was a rapid expansion of development, under influence of Sao Paulo city. Furthermore, the past(1962)road network was more important than the recent road network (1981) when explaining forest dynamics between 1981 and 2000, suggesting a long-term effect of roads. Roads are permanent scars on the landscape and facilitate deforestation and forest fragmentation due to increased accessibility and land valorization, which control land-use and land-cover dynamics. Topography directly affected deforestation, agriculture and road expansion, mainly between 1962 and 1981. Forest are thus in peril where there are more roads, and long-term conservation strategies should consider ways to mitigate roads as permanent landscape features and drivers facilitators of deforestation and forest fragmentation. (C) 2009 Elsevier B.V. All rights reserved.

Structural basis for selective inhibition of trypanosomatid glyceraldehyde-3-phosphate dehydrogenase: Molecular docking and 3D QSAR studies

The glycolytic enzyme glyceraldehyde-3 -phosphate dehydrogenase (GAPDH) is as an attractive target for the development of novel antitrypanosomatid agents. In the present work, comparative molecular field analysis and comparative molecular similarity index analysis were conducted on a large series of selective inhibitors of trypanosomatid GAPDH. Four statistically significant models were obtained (r(2) > 0.90 and q(2) > 0.70), indicating their predictive ability for untested compounds. The models were then used to predict the potency of an external test set, and the predicted values were in good agreement with the experimental results. Molecular modeling studies provided further insight into the structural basis for selective inhibition of trypanosomatid GAPDH.

The reduction of Cu(II)/neocuproine complexes by some polyphenols: Total polyphenols determination in wine samples

A new method is presented for spectrophotometric determination of total polyphenols content in wine. The procedure is a modified CUPRAC method based on the reduction of Cu(II), in hydroethanolic medium (pH 7.0) in the presence of neocuproine (2,9-dimethyl-1,10-phenanthroline), by polyphenols, yielding a Cu(I) complexes with maximum absorption peak at 450 nm. The absorbance values are linear (r = 0.998, n = 6) with tannic acid concentrations from 0.4 to 3.6 mu mol L(-1). The limit of detection obtained was 0.41 mu mol L(-1) and relative standard deviation 1.2% (1 mu mol L(-1); n = 8). Recoveries between 80% and 110% (mean value of 95%) were calculated for total polyphenols determination in 14 commercials and 2 synthetic wine samples (with and without sulphite). The proposed procedure is about 1.5 more sensitive than the official Folin-Ciocalteu method. The sensitivities of both methods were compared by the analytical responses of several polyphenols tested in each method. (C) 2010 Elsevier Ltd. All rights reserved.

Atratividade em clusters comerciais: um estudo comparativo de dois clusters da cidade de São Paulo

O presente trabalho teve como objetivo a identificação de atributos relacionados à atratividade de clientes em clusters comerciais, na percepção de consumidores. Partindo-se da atratividade de clientes para lojas, desenvolveu-se um construto de avaliação de atratividade de clientes para clusters comerciais. Por meio de estudo descritivo-quantitativo junto a 240 consumidores, em dois reconhecidos clusters comerciais, utilizando-se a técnica de PLS-PM (Partial Least Squares Path Modeling), avaliou-se a relação entre a atratividade de clientes (variável reflexiva) e as dimensões do mix varejista de clusters comerciais (variáveis latentes), a partir do tratamento de indicadores de efeitos observáveis. Como principais resultados, observou-se que: (1) atratividade está associada significativamente às variáveis latentes, sugerindo robustez do modelo; (2) condições de compra e preços são dimensões com maior associação à atratividade de clientes, embora lojas, produtos e atendimento apresentem relevância; e (3) localização apresentou-se como dimensão menos correlacionada à atratividade de clientes para ambos os clusters.

An analysis of critical success factors in ERP implementation

Essa tese foca em diferentes perspectivas sobre CSF (Fatores Críticos de Sucess) em implementações de ERP (Enterprise Resource Planning). A literatura atual foca nos CSF sob o ponto de vista da alta gerência da organização e classifica esses CSF baseado nessa visão. Essa tese irá apresentar a visão do time de implementação de ERP sob os principais CSF e irá utilizar um estudo de caso para avaliar se a alta gerência e o time de implementação compartilham a mesma visão. Além disso ess tese irá propor uma relação entre o sucesso na implementação de ERP e os CSF pesquisados, usando o método PLS (Partial Least Squares) para analisar as respostas do time de implementação a um questionário desenvolvido para medir sucesso na implementação de ERP.

Viagem ao centro da denúncia: explorando as “camadas” que influenciam as denúncias de fraudes nas organizações

As fraudes contábeis representam uma grande perda para a economia global tanto na esfera pública quanto privada, destacando, assim, os prejuízos sociais ocasionados por elas. Nesta perspectiva, diversas pesquisas têm demonstrado que as denúncias são um dos principais mecanismos de detecção de fraudes nas organizações. Inspirado em Taylor e Curtis (2010), o presente trabalho tem como objetivo identificar a influência das “camadas” pessoal, organizacional, profissional na intenção individual em denunciar uma situação fraudulenta que o mesmo tenha conhecimento. Ressalta-se, porém, a inclusão de uma “camada social”, bem como a consideração de aspectos peculiares da cultura brasileira na elaboração e análise das hipóteses. Para operacionalização das camadas foram utilizadas variáveis latentes coletadas por meio de um questionário respondido por 124 contabilistas. Para mensuração da influência na intenção em denunciar foi utilizado um Modelo de Equação Estrutural (SEM) estimado pelo método dos Mínimos Quadrados Parciais (PLS). Os resultados obtidos confirmaram a importância das camadas de influência no comportamento do eventual denunciante. Destaca-se, principalmente, a importância da camada social, a qual, além de influenciar diretamente de forma significativa a Intenção de Denunciar, também media o impacto da camada profissional. A camada organizacional não afeta de forma significante a intenção de denunciar. Nota-se, também o grande impacto causado pela camada pessoal. Tais fatos corroboram alguns dos principais traços da cultura brasileira, como a prevalência de relações informais e pessoais em detrimento de relações formais, além de identificar os traços da ambiguidade moral.

Mapeando os valores subjetivos dos gerentes de relacionamento em negociações bancárias

No contexto de um mercado tão competitivo, ter equipes bem preparadas e alocadas adequadamente é fundamental para a sobrevivência das empresas. O presente estudo objetiva identificar o reflexo na satisfação dos clientes e nos resultados das empresas, a partir do conhecimento das pessoas que trabalham na linha de frente dessas empresas, aqueles profissionais que exercem um papel importante de negociação, identificando o que eles valorizam subjetivamente em uma negociação. Por meio da ferramenta SVI (Subjective Value Inventory), desenvolvida por Curhan et al (2006), a partir das dimensões de autoimagem independente e interdependente, busca-se identificar os valores subjetivos dos negociadores de um banco de varejo brasileiro, responsáveis por parte significativa das negociações e dos resultados da empresa, relativamente aos sentimentos sobre si mesmos (Self), aos resultados instrumentais, e ao processo e relacionamento (Rapport), utilizando a confiança interpessoal como moderadora nessa relação. Após identificados os valores subjetivos desses negociadores em negociação, relacionar os resultados encontrados com a satisfação dos clientes. Para isso, foi realizada uma pesquisa quantitativa, com a aplicação de um questionário fechado e estruturado a 532 negociadores desse banco que atuam nos estados de Santa Catarina, Rio de Janeiro e Maranhão, responsáveis pelo relacionamento, prospecção e realização de negócios com os clientes da instituição, nos segmentos pessoa física, micro e pequenas empresas e governo. Os dados foram analisados a partir de técnicas estatísticas, utilizando-se o método dos Mínimos Quadrados Parciais. Observou-se que mais de 40% da satisfação de cliente é explicada pelos valores subjetivos dos negociadores. O estudo apontou como resultados, dentre outros, que os gerentes de negócios com autoimagem independente valorizam o Self e os resultados instrumentais em uma negociação, e que a confiança interpessoal cognitiva modera negativamente essa relação. Ainda, que aqueles gerentes de negócios com autoimagem interdependente, valorizam o Rapport em uma negociação e que essa valorização está positivamente relacionada com a satisfação dos clientes.

Growing research where economies grow: essays on strategy and international expansion of companies from emerging countries

In recent years, emerging countries have assumed an increasingly prominent position in the world economy, as growth has picked up in these countries and slowed in developed economies. Two related phenomena, among others, can be associated with this growth: emerging countries were less affected by the 2008-2009 global economic recession; and they increased their participation in foreign direct investment, both inflows and outflows. This doctoral dissertation contributes to research on firms from emerging countries through four independent papers. The first group of two papers examines firm strategy in recessionary moments and uses Brazil, one of the largest emerging countries, as setting for the investigation. Data were collected through a survey on Brazilian firms referring to the 2008-2009 global recession, and 17 hypotheses were tested using structural equation modeling based on partial least squares. Paper 1 offered an integrative model linking RBV to literatures on entrepreneurship, improvisation, and flexibility to indicate the characteristics and capabilities that allow a firm to have superior performance in recessions. We found that firms that pre-recession have a propensity to recognize opportunities and improvisation capabilities for fast and creative actions have superior performance in recessions. We also found that entrepreneurial orientation and flexibility have indirect effects. Paper 2 built on business cycle literature to study which strategies - pro-cyclical or counter-cyclical – enable superior performance in recessions. We found that while most firms pro-cyclically reduce costs and investments during recessions, a counter-cyclical strategy of investing in opportunities created by changes in the environment enables superior performance. Most successful are firms with a propensity to recognize opportunities, entrepreneurial orientation to invest, and flexibility to efficiently implement these investments. The second group of two papers investigated international expansion of multinational enterprises, particularly the use of distance for their location decisions. Paper 3 proposed a conceptual framework to examine circumstances under which distance is less important for international location decisions, taking the new perspective of economic institutional distance as theoretical foundation. The framework indicated that the general preference for low-distance countries is lower: (1) when the company is state owned, rather than private owned; (2) when its internationalization motives are asset, resource, or efficiency seeking, as opposed to market seeking; and (3) when internationalization occurred after globalization and the advent of new technologies. Paper 4 compared five concurrent perspectives of distance and indicated their suitability to the study of various issues based on industry, ownership, and type, motive, and timing of internationalization. The paper also proposed that distance represents the disadvantages of host countries for international location decisions; as such, it should be used in conjunction with factors that represent host country attractiveness, or advantages as international locations. In conjunction, papers 3 and 4 provided additional, alternative explanations for the mixed empirical results of current research on distance. Moreover, the studies shed light into the discussion of differences between multinational enterprises from emerging countries versus those from advanced countries.