451 resultados para PLS DA


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Technological advances at the level of mobile devices are transforming the world. Banking users are able to conduct banking services at any place, and at any time, with m-banking. The purpose of this research is to analyse intention and action in m-banking services. A research model was developed and PLS was used to test the causalities in the proposed model. Our proposal extends the existing models with an assessment of the actual usage of m-banking and of how behavioural intention translates into action. This study found that the main determinants of behavioural intention for m-banking are social influence and relative advantage. Furthermore, perceived risk, lack of information and usage barriers have a negative effect on m- banking behavioural intention. Perceived risks, e-banking use, and behaviour intention are found to be significant antecedents of m-banking use. Gender has a positive and significant influence on m-banking usage, but not on the construction of behavioural intention.

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Purpose: To develop an effective method for evaluating the quality of Cortex berberidis from different geographical origins. Methods: A simple, precise and accurate high performance liquid chromatography (HPLC) method was first developed for simultaneous quantification of four active alkaloids (magnoflorine, jatrorrhizine, palmatine, and berberine) in Cortex berberidis obtained from Qinghai, Tibet and Sichuan Provinces of China. Method validation was performed in terms of precision, repeatability, stability, accuracy, and linearity. Besides, partial least squares discriminant analysis (PLS-DA) and one-way analysis of variance (ANOVA) were applied to study the quality variations of Cortex berberidis from various geographical origins. Results: The proposed HPLC method showed good linearity, precision, repeatability, and accuracy. The four alkaloids were detected in all samples of Cortex berberidis. Among them, magnoflorine (36.46 - 87.30 mg/g) consistently showed the highest amounts in all the samples, followed by berberine (16.00 - 37.50 mg/g). The content varied in the range of 0.66 - 4.57 mg/g for palmatine and 1.53 - 16.26 mg/g for jatrorrhizine, respectively. The total content of the four alkaloids ranged from 67.62 to 114.79 mg/g. Moreover, the results obtained by the PLS-DA and ANOVA showed that magnoflorine level and the total content of these four alkaloids in Qinghai and Tibet samples were significantly higher (p < 0.01) than those in Sichuan samples. Conclusion: Quantification of multi-ingredients by HPLC combined with statistical methods provide an effective approach for achieving origin discrimination and quality evaluation of Cortex berberidis. The quality of Cortex berberidis closely correlates to the geographical origin of the samples, with Cortex berberidis samples from Qinghai and Tibet exhibiting superior qualities to those from Sichuan.

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Circulating low density lipoproteins (LDL) are thought to play a crucial role in the onset and development of atherosclerosis, though the detailed molecular mechanisms responsible for their biological effects remain controversial. The complexity of biomolecules (lipids, glycans and protein) and structural features (isoforms and chemical modifications) found in LDL particles hampers the complete understanding of the mechanism underlying its atherogenicity. For this reason the screening of LDL for features discriminative of a particular pathology in search of biomarkers is of high importance. Three major biomolecule classes (lipids, protein and glycans) in LDL particles were screened using mass spectrometry coupled to liquid chromatography. Dual-polarity screening resulted in good lipidome coverage, identifying over 300 lipid species from 12 lipid sub-classes. Multivariate analysis was used to investigate potential discriminators in the individual lipid sub-classes for different study groups (age, gender, pathology). Additionally, the high protein sequence coverage of ApoB-100 routinely achieved (70%) assisted in the search for protein modifications correlating to aging and pathology. The large size and complexity of the datasets required the use of chemometric methods (Partial Least Square-Discriminant Analysis, PLS-DA) for their analysis and for the identification of ions that discriminate between study groups. The peptide profile from enzymatically digested ApoB-100 can be correlated with the high structural complexity of lipids associated with ApoB-100 using exploratory data analysis. In addition, using targeted scanning modes, glycosylation sites within neutral and acidic sugar residues in ApoB-100 are also being explored. Together or individually, knowledge of the profiles and modifications of the major biomolecules in LDL particles will contribute towards an in-depth understanding, will help to map the structural features that contribute to the atherogenicity of LDL, and may allow identification of reliable, pathology-specific biomarkers. This research was supported by a Marie Curie Intra-European Fellowship within the 7th European Community Framework Program (IEF 255076). Work of A. Rudnitskaya was supported by Portuguese Science and Technology Foundation, through the European Social Fund (ESF) and "Programa Operacional Potencial Humano - POPH".

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A elevada incidncia e mortalidade mundiais associadas ao cancro justificam o desenvolvimento e implementao de estratgias eficazes e no-invasivas conducentes a um diagnstico precoce. Neste contexto, pretendeu-se avaliar a performance de uma metodologia inovadora, a microextrao por needle trap (NTME), na extrao de metabolitos volteis (VOMs) da urina de pacientes oncolgicos com diferentes tipos de cancro - clon, pulmo e mama, e de indivduos saudveis, com a finalidade de identificar um conjunto de VOMs potenciais biomarcadores dos diferentes tipos cancros em estudo. De modo a maximizar a eficincia da extrao dos VOMs, foram otimizados diferentes parmetros experimentais, nomeadamente a natureza do sorvente, a temperatura, o tempo de equilbrio, o volume de headspace, a fora inica, o pH do meio e o volume e a agitao da amostra. Usando como sorvente o DVB/Car1000/CarX, os melhores resultados foram obtidos com 4 mL de urina acidificada (pH= 2), 20% NaCl, 40 mL de headspace e 40 min de equilbrio a 50 C. Foi ainda avaliada a estabilidade dos VOMs no sorvente at 72 h aps a extrao. Nos quatro grupos em estudo foram identificados, por GC-MS, 259 VOMs pertencentes a diversas famlias qumicas, nomeadamente cetonas, compostos sulfurados, furnicos e terpnicos. A matriz de dados obtida para cada grupo em estudo foi submetida a anlise discriminante, usando o mtodo dos mnimos quadrados parciais (PLS-DA), que resultou em clusters distintos diferenciadores de cada grupo. A aplicabilidade do modelo foi avaliada atravs do mtodo de classificao SIMCA (modelagem suave e independente de analogias de classe), com elevadas taxas de classificao, sensibilidade e especificidade. Este foi o primeiro estudo usando NTME para o estabelecimento do padro volatmico da urina. Os resultados obtidos revelam-se muito promissores originando perfis volteis de maior expressividade, mais completos e abrangentes, que os obtidos usando metodologias de referncia.

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Brands are those lifestyles which consumers chose to buy in order to gain the value offered by the company, in order to be part of the community created through the brand equity elements and validated in the purchase of the products. Companies have understood how important it is to build a strong brand and many of them spend millions on aligning the brand with the design and style of the products, projecting the face and values of the company into the advertising campaigns. One of the most popular methods is through endorsement, placing a renounced celebrity and leveraging on the positive feedback of those customers that also follow the activities of the star whose face is on the cover of the marcom campaign. Celebrities have been used for a very long time to promote brands, sell products and services. Research has shown that those spokesmen of a brand who are more attractive can improve the statistics of recall and appeal more interest to the promotion campaign, as well as influence more on customers intention of buying the product (Kahle and Homer, 1985). The main purpose of this research is to investigate how celebrity endorsements influence the brand equity dimensions (brand loyalty, brand awareness, perceived quality and brand associations) as well as stimulate consumers word-of-mouth through brand identification, growth in interest and the advertising memorability. The hypotheses were tested with the aid of Structural Equation Modelling (SEM) in the PLS (Partial Least Squares) software. The survey is comprised of a target group of 589 respondents, from three countries Brazil, Moldova and Portugal. Results evidence that the Attitude towards the Celebrity influences different Brand Equity dimensions and affects brand identification, growth in advertisement interest and advertising memorability, generating positive word of mouth (or negative, depending on the type of advertisement and reputation). Based on these findings we suggest further investigation in this area with the possibility to gain more data about the different fields of marcom and the different types of CE which are more appropriate for the given type of business.

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The home support services are a social response in order to improve the quality of life directed predominantly for the elderly and for people with varying degrees of disability and dependence. Examples of those services are hygiene and personal comfort, medication, housekeeping and cleaning, preparation and monitoring of the meals; the dressing, etc. It is necessary to make society aware of the importance of these services to all those who need them. The general objective was to understand the most important relationships among informal caregivers, those who are care and home support services providers. Material and Methods. Data were collected through a questionnaire, using the various dimensions of the construct Quality SERVPERF model of service that matches the 22 items of SERVQUAL model. The various items used to assess the perception of care individuals and informal caregivers about the quality of home care services. 82 individuals participated providers of informal care, to receive home support services, and exclusion criteria, the fact of having a diagnosed psychiatric illness or psychological factors that prevent them from responding. The analysis was performed with SPSS and SEM-PLS for the estimation of the proposed structural model. Written consent was obtained, free and clear of each subject. Results and Conclusions. The results showed that the relationships with healthcare professionals are the most important positive effects on satisfaction. This research emphasizes the need to work closely with health professionals to improve the relationship between technicians and patients. Although current constructs appear to explain much of the satisfaction, it is recommended that the future researches exploit new variables, to get a better understanding of the effects of public health policies on the quality of life of these patients.

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Esta investigacin de carcter exploratorio, contribuye a explicar cmo afecta al comportamiento innovador de la pyme manufacturera dos filosofas empresariales. En concreto, se estudia el impacto sobre el comportamiento innovador del compromiso por la calidad y del fomento de una cultura emprendedora, bajo un enfoque de direccin participativa. Para ello se establece un modelo estructural con las relaciones entre dichas variables y se analiza con la tcnica PLS (Partial Least Squares). Los resultados muestran que tanto una como otra postura afectan al comportamiento innovador de una manera muy similar.

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Tesis indita presentada en la Universidad Europea de Madrid. Facultad de Ciencias Sociales. Programa de Doctorado en Economa y Empresa

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Tese apresentada ao Programa de Ps-Graduao em Administrao da Universidade Municipal de So Caetano do Sul como requisito para a obteno do ttulo de Doutora em Administrao.

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A elevada incidncia e mortalidade mundiais associadas ao cancro justificam o desenvolvimento e implementao de estratgias eficazes e no-invasivas conducentes a um diagnstico precoce. Neste contexto, pretendeu-se avaliar a performance de uma metodologia inovadora, a microextrao por needle trap (NTME), na extrao de metabolitos volteis (VOMs) da urina de pacientes oncolgicos com diferentes tipos de cancro - clon, pulmo e mama, e de indivduos saudveis, com a finalidade de identificar um conjunto de VOMs potenciais biomarcadores dos diferentes tipos cancros em estudo. De modo a maximizar a eficincia da extrao dos VOMs, foram otimizados diferentes parmetros experimentais, nomeadamente a natureza do sorvente, a temperatura, o tempo de equilbrio, o volume de headspace, a fora inica, o pH do meio e o volume e a agitao da amostra. Usando como sorvente o DVB/Car1000/CarX, os melhores resultados foram obtidos com 4 mL de urina acidificada (pH= 2), 20% NaCl, 40 mL de headspace e 40 min de equilbrio a 50 C. Foi ainda avaliada a estabilidade dos VOMs no sorvente at 72 h aps a extrao. Nos quatro grupos em estudo foram identificados, por GC-MS, 259 VOMs pertencentes a diversas famlias qumicas, nomeadamente cetonas, compostos sulfurados, furnicos e terpnicos. A matriz de dados obtida para cada grupo em estudo foi submetida a anlise discriminante, usando o mtodo dos mnimos quadrados parciais (PLS-DA), que resultou em clusters distintos diferenciadores de cada grupo. A aplicabilidade do modelo foi avaliada atravs do mtodo de classificao SIMCA (modelagem suave e independente de analogias de classe), com elevadas taxas de classificao, sensibilidade e especificidade. Este foi o primeiro estudo usando NTME para o estabelecimento do padro volatmico da urina. Os resultados obtidos revelam-se muito promissores originando perfis volteis de maior expressividade, mais completos e abrangentes, que os obtidos usando metodologias de referncia.

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El pandillismo es un fenmeno social que se presenta en las principales ciudades de Colombia desde hace varias dcadas, sin embargo, solo en los ltimos aos el fenmeno a comenzado a acaparar mayor atencin meditica e institucional. El pandillismo se ha convertido en una preocupacin para la seguridad ciudadana, especialmente en las reas urbanas. La Polica Nacional, en conjunto a Instituciones locales y nacionales ha venido realizando un trabajo focalizado para hacerle pie al fenmeno. En este trabajo se realiz una revisin histrica del pandillismo en Bogot y un panorama continental. De la misma manera, se hace una descripcin de los programas y estrategias que la Polica Nacional y las entidades pblicas han realizado desde el ao 2004 hasta el ao 2015. Por ltimo se realiza una evaluacin del trabajo institucional enfocado en el sector del Codito, en la localidad de Usaqun.

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La presente investigacin pretendi incorporar el uso intensivo de TIC en los procedimientos establecidos y necesarios en los procesos de generacin, distribucin y control de la energa, lo que se expresa en un manual para el sistema de gestin humana de la organizacin analizada. La investigacin parti de un levantamiento de un estado del arte, continu con la realizacin de un anlisis de actitudes y aptitudes de los colaboradores, basado en propuestas tericas y mejores prcticas existentes del medio, y, por ltimo, concluy con un manual de gestin humana en el que se indican las competencias en los diferentes perfiles de la organizacin para el uso de TIC y su aplicacin, con el propsito de alinearse con las perspectivas y objetivos de la organizacin analizada al tener como base la perdurabilidad y la competitividad de la misma.

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Este documento evidencia las posiciones hegemnicas que han llegado a ocupar las empresas ms poderosas del pas, basndose en el estudio de datos cuantitativos del conteo de las cien empresas con mejores ventas para los aos 2013 y 2014, segn la revista Gerente. Se usan cinco variables: ventas totales, activos, pasivos, patrimonio y utilidades netas. En la primera seccin, se hace una revisin bibliogrfica que conecta el origen de la hegemona en un panorama econmico con la influencia del neoliberalismo y la globalizacin en el actual tejido industrial colombiano. Posteriormente, se realiza una explicacin sobre la metodologa aplicada para el estudio de la base de datos; la cual es seguida por una exposicin de los resultados obtenidos a partir de herramientas estadsticas como el anlisis de correlacin lineal, quintiles y variaciones porcentuales. Finalmente, se aborda el Programa de Transformacin Productiva, esto con el objetivo de mostrar los puntos focales que necesitan especial atencin para lograr catalizar el desarrollo econmico de Colombia.

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The near infrared (NIR) spectroscopy presents itself as an interesting non-destructive test tool as it enables a fast, simple and reliable way for characterizing large samplings of biological materials in a short period of time. This work aimed to establish multivariate models to estimate the crystallinity indices and tensile and burst strength of cellulosic and nanocellulosic films through NIR spectroscopy. NIR spectra were recorded from the films before tensile and bursting strength, and crystallinity tests. Spectral information were correlated with reference values obtained by laboratory procedures through partial least square regression (PLS-R). The PLS-R model for estimating the crystallinity index presented a coefficient of determination in cross-validation (R2cv) of 0,94 and the ratio of performance to deviation (RPD) was 3,77. The mechanical properties of the films presented a high correlation with the NIR spectra: R2p = 0,85 (RPD = 2,23) for tensile and R2p = 0,93 (RPD = 3,40) for burst strength. The statistics associated to the models presented have shown that the NIR spectroscopy has the potential to estimate the crystallinity index and resistance properties of cellulose and nanocellulose films on in-line monitoring systems.

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Espcies forrageiras adaptadas s condies semiridas so uma alternativa para reduzir os impactos negativos na cadeia produtiva de ruminantes da regio Nordeste brasileira devido sazonalidade na oferta de forragem, alm de reduzir custo com o fornecimento de alimentos concentrados. Dentre as espcies, a vagem de algaroba (Prosopis juliflora SW D.C.) e palma forrageira (Opuntia e Nopalea) ganham destaque por tolerarem o dficit hdrico e produzirem em perodos onde a oferta de forragem est reduzida, alm de apresentam bom valor nutricional e serem bem aceitas pelos animais. Porm, devido variao na sua composio, seu uso na alimentao animal exige o conhecimento profundo da sua composio para a elaborao de dietas balanceadas. No entanto, devido ao custo e tempo para anlise, os produtores no fazem uso da prtica de anlise da composio qumico-bromatolgica dos alimentos. Por isto, a espectroscopia de reflectncia no infravermelho prximo (NIRS) representa uma importante alternativa aos mtodos tradicionais. Objetivou-se com este estudo desenvolver e validar modelos de predio da composio bromatolgica de vagem de algaroba e palma forrageira baseados em espectroscopia NIRS, escaneadas em dois modelos de equipamentos e com diferentes processamentos da amostra. Foram coletadas amostras de vagem de algaroba nos estados do Cear, Bahia, Paraba e Pernambuco, e amostras de palma forrageira nos estados do Cear, Paraba e Pernambuco, frescas (in natura) ou pr-secas e modas. Para obteno dos espectros utilizaram-se dois equipamentos NIR, Perten DA 7250 e FOSS 5000. Inicialmente os alimentos foram escaneados in natura em aparelho do modelo Perten, e, com o auxlio do software The Unscrambler 10.2 foi selecionado um grupo de amostras para o banco de calibrao. As amostras selecionadas foram secas e modas, e escaneadas novamente em equipamentos Perten e FOSS. Os valores dos parmetros de referncia foram obtidos por meio de metodologias tradicionalmente aplicadas em laboratrio de nutrio animal para matria seca (MS), matria mineral (MM), matria orgnica (MO), protena bruta (PB), estrato etreo (EE), fibra solvel em detergente neutro (FDN), fibra solvel em detergente cido (FDA), hemicelulose (HEM) e digestibilidade in vitro da matria seca (DIVMS). O desempenho dos modelos foi avaliado de acordo com os erros mdios de calibrao (RMSEC) e validao (RMSECV), coeficiente de determinao (R2 ) e da relao de desempenho de desvio dos modelos (RPD). A anlise exploratria dos dados, por meio de tratamentos espectrais e anlise de componentes principais (PCA), demonstraram que os bancos de dados eram similares entre si, dando segurana de desenvolver os modelos com todas as amostras selecionadas em um nico modelo para cada alimento, algaroba e palma. Na avaliao dos resultados de referncia, observou-se que a variao dos resultados para cada parmetro corroboraram com os descritos na literatura. No desempenho dos modelos, aqueles desenvolvidos com pr-processamento da amostra (pr-secagem e moagem) se mostraram mais robustos do que aqueles construdos com amostras in natura. O aparelho NIRS Perten apresentou desempenho semelhante ao equipamento FOSS, apesar desse ltimo cobrir uma faixa espectral maior e com intervalos de leituras menores. A tcnica NIR, associada ao mtodo de calibrao multivariada de regresso por meio de quadrados mnimos (PLS), mostrou-se confivel para prever a composio qumico-bromatolgica de vagem de algaroba e da palma forrageira. Abstract: Forage species adapted to semi-arid conditions are an alternative to reduce the negative impacts in the feed supply for ruminants in the Brazilian Northeast region, due to seasonality in forage availability, as well as in the reducing of cost by providing concentrated feedstuffs. Among the species, mesquite pods (Prosopis juliflora SW DC) and spineless cactus (Opuntia and Nopalea) are highlighted for tolerating the drought and producion in periods where the forage is scarce, and have high nutritional value and also are well accepted by the animals. However, its use in animal diets requires a knowledge about its composition to prepare balanced diets. However, farmers usually do not use feed composition analysis, because their high cost and time-consuming. Thus, the Near Infrared Reflectance Spectroscopy in the (NIRS) is an important alternative to traditional methods. The objective of this study to develop and validate predictive models of the chemical composition of mesquite pods and spineless cactus-based NIRS spectroscopy, scanned in two different spectrometers and sample processing. Mesquite pods samples were collected in the states of Cear, Bahia, Paraiba and Pernambuco, and samples of forage cactus in the states of Cear, Paraba and Pernambuco. In order to obtain the spectra, it was used two NIR equipment: Perten DA 7250 and FOSS 5000. sSpectra of samples were initially obtained fresh (as received) using Perten instrument, and with The Unscrambler software 10.2, a group of subsamples was selected to model development, keeping out redundant ones. The selected samples were dried and ground, and scanned again in both Perten and FOSS instruments. The values of the reference analysis were obtained by methods traditionally applied in animal nutrition laboratory to dry matter (DM), mineral matter (MM), organic matter (OM), crude protein (CP), ether extract (EE), soluble neutral detergent fiber (NDF), soluble acid detergent fiber (ADF), hemicellulose ( HEM) and in vitro digestibility of dry matter (DIVDM). The performance of the models was evaluated according to the Root Mean Square Error of Calibration (RMSEC) and cross-validation (RMSECV), coefficient of determination (R2 ) and the deviation of Ratio of performance Deviation of the models (RPD). Exploratory data analysis through spectral treatments and principal component analysis (PCA), showed that the databases were similar to each other, and may be treated asa single model for each feed - mesquite pods and cactus. Evaluating the reference results, it was observed that the variation were similar to those reported in the literature. Comparing the preprocessing of samples, the performance ofthose developed with preprocessing (dried and ground) of the sample were more robust than those built with fresh samples. The NIRS Perten device performance similar to FOSS equipment, although the latter cover a larger spectral range and with lower readings intervals. NIR technology associate do multivariate techniques is reliable to predict the bromatological composition of mesquite pods and cactus.