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O gerenciamento de processos de negócios (BPM) é um instrumento que auxilia no monitoramento do desempenho das organizações, promovendo uma visão sistêmica do ambiente interno e externo a organização, com relação a todos os participantes e processos, bem como suas inter-relações. O objetivo desse trabalho é avaliar o relacionamento e influência entre os elementos centrais às práticas de BPM e o desempenho organizacional, considerando informações de empresas situadas no Arranjo Produtivo Local (APL) Têxtil do Agreste de Pernambuco, haja vista sua relevância dentro da economia internacional, nacional e regional. As hipóteses propostas quanto ao relacionamento entre os processos foram testadas utilizando o método dos mínimos quadrados parciais, com o auxílio do software SmartPLS 3.0. Como resultados observados, são destacadas a proposição e confirmação de relacionamentos, dentre outros, ao alinhamento estratégico e governança, bem como a governança e o uso de tecnologia da informação, e o uso de tecnologia da informação e cultura organizacional.

Cybersecurity, which is defined as information security aimed at averting cyberattacks, which are among the main issues caused by the extensive use of networks in industrial control systems. This paper proposes a model that integrates fault tree analysis, decision theory and fuzzy theory to (i) ascertain the current causes of cyberattack prevention failures and (ii) determine the vulnerability of a given cybersecurity system. The model was applied to evaluate the cybersecurity risks involved in attacking a website, e-commerce and enterprise resource planning (ERP), and to assess the possible consequences of such attacks; we evaluate these consequences, which include data dissemination, data modification, data loss or destruction and service interruption, in terms of criteria related to financial losses and time for restoration. The results of the model application demonstrate its usefulness and illustrate the increased vulnerability of e-commerce to cybersecurity attacks, relative to websites or ERP, due partly to frequent operator access, credit transactions and users’ authentication problems characteristic of e-commerce.

Uma vez que os investimentos em Tecnologia da Informação e Comunicação (TIC) têm crescido dentro das organizações, e a estes estão associados desafios quanto a identificação e quantificação dos retornos, estudos neste sentido se tornam de grande importância. Uma tendência de investimentos nos últimos anos é a adoção de Sistemas de Informação (SIs) integrados ou a integração dos já existentes nas empresas. As razões que levam os gestores a adotarem tais formas de investimentos em TIC são, de maneira geral, a busca por melhorias de desempenho e vantagem competitiva, tendo em vista, os ambientes de negócio cada vez mais dinâmicos. Diante disto, o presente trabalho teve como objetivo investigar o impacto da integração de SIs na competitividade das empresas pernambucanas de diversos setores. Para tanto, uma coleta de dados foi realizada por meio um questionário elaborado nos formatos físico e online e enviado às empresas, além de testes de hipótese com os dados obtidos. Os resultados identificados demonstraram a influência da integração sobre a compreensão do negócio, aprendizado dos funcionários e inovação, enquanto que, nenhuma relação pôde ser constatada no que se refere a custos e controle de atividades.

Recycling and sustainable development issues are increasing in importance around the world. This aspect is more prominent in developing countries, in which there are many informal recycling activities and few environmental legislations regulating waste management. This chapter discusses the recycling challenges regarding the adoption of e-waste reverse logistics under the perspective of developing countries. For this purpose, we gathered information from papers published in international databases and reports such as the United Nations Environment Programme and Global e-waste Monitor, thus identifying data available to American countries (Brazil, Argentina, Chile and Mexico), South Africa and Asian countries (China, India, Russia, Indonesia, Turkey, Pakistan, South Korea, Thailand and Singapore). As key findings we can point out the categorization of the barriers into financial/economics, environmental, market related, legal, policy related, management, knowledge related and technical and technological related. As main contributions of this chapter, we can highlight (i) the compilation of information related to recycling challenges of e-waste in developing countries, and (ii) the identification of some solutions and actions to overcome these barriers is also performed, which can be useful for practitioners and researchers in this field.

Purpose: To evaluate the hyaluronic acid (HA) inflammatory reaction, fibroblasts, fibrosis and duration of effect in the dorsal region of tobacco-exposed rats. Methods: Ten Wistar rats were divided into two groups: tobacco-exposed-group (TEG;n=5) and air-control-group (CG;n=5). The TEG animals were tobacco-exposed twice a day, 30-minutes/session, during 60 days. After this period, all animals received 0.1 mL HA subcutaneous injection in the dorsal area. The volume of HA was measured immediately after HA injection and weekly using a hand-caliper in nine weeks. After this period, all the animals were euthanized, and a specimen of was collected to evaluate inflammatory cells, fibroblasts, and fibrosis by HE. Results: This study showed a higher inflammatory reaction in TEG than CG: inflammatory cell-count (CG: 1.07±0.9; TEG: 8.61±0.36, p

The National Policy of Solid Waste, recently approved in Brazil, establishes the implementation of reverse logistics networks for several residues, such as electronic waste. One of the primary points of the legislation is the principle of ‘shared responsibility’, which establishes that all actors in a supply chain are responsible for the reverse logistics, such as manufacturers, distributors, importers, retailers, the government and the final consumer. This situation characterizes a group decision context and, emphasises the need of aggregate different and often conflicting viewpoints. Thus, this paper proposes the use of a specific Problem Structuring Method, the Strategic Options Development Analysis, which is based on the construction of cognitive mapping techniques, for developing strategic analysis based on the decision-makers' viewpoints. In order to apply the methodology, we conducted online workshops with 8 representatives of the stakeholders involved in this decision context. At the end of the process, four categories of actions to be implemented were found and developed: strategic, environmental, economic and social. These categories are based not only to technically assessment, but also on stakeholder's perspectives. The contribution of this paper is mainly related to the analysis and structuration of the problem of reverse logistics of electronic waste under a problem structuring methodology, which is few explored in the literature. This paper also contributes to researchers estudying reverse logistics of electronic waste, mainly in developing countries.

A risk analysis model for information security was proposed.The model is based on fuzzy decision theory.A taxonomy of events and scenarios using ETA methodology was developed.Alternatives can be ranked based on the criticality of the risk.The model provides information regarding the criticality causes of attacks.Results show that deliberate external database attack is the most risky alternative. This paper proposes a risk analysis model for information security assessment, which identifies and evaluates the sequence of events - referred to as alternatives - in a potential accident scenario following the occurrence of an initiating event corresponding to abuses of Information Technology systems. In order to perform this evaluation, this work suggests the use of Event Tree Analysis combined with fuzzy decision theory. The contributions of the present proposal are: the development of a taxonomy of events and scenarios, the ranking of alternatives based on the criticality of the risk, considering financial losses, and finally, the provision of information regarding the causes of information system attacks of highest managerial relevance for organizations. We included an illustrative example regarding a data center aiming to illustrate the applicability of the proposed model. To assess its robustness, we analyzed twelve alternatives considering two different methods of setting probabilities of the occurrence of events. Results showed that deliberate external database services attack represent the most risky alternative.

Big data is the term used to denote enormous sets of data that differ from other classic databases in four main ways: (huge) volume, (high) velocity, (much greater) variety, and (big) value. In general, data are stored in a distributed fashion and on computing nodes as a result of which big data may be more susceptible to attacks by hackers. This paper presents a risk model for big data, which comprises Failure Mode and Effects Analysis (FMEA) and Grey Theory, more precisely grey relational analysis. This approach has several advantages: it provides a structured approach in order to incorporate the impact of big data risk factors; it facilitates the assessment of risk by breaking down the overall risk to big data; and finally its efficient evaluation criteria can help enterprises reduce the risks associated with big data. In order to illustrate the applicability of our proposal in practice, a numerical example, with realistic data based on expert knowledge, was developed. The numerical example analyzes four dimensions, that is, managing identification and access, registering the device and application, managing the infrastructure, and data governance, and 20 failure modes concerning the vulnerabilities of big data. The results show that the most important aspect of risk to big data relates to data governance.

Manter as condições socioambientais em um estado de conservação favorável para que a sociedade se desenvolva sem restrições é a ideia que embasa o conceito de Sustentabilidade. Diversas esferas como as mídias, a academia e as organizações passaram a dar maior importância para o estudo da sustentabilidade, uma vez que ela impacta diretamente em aspectos que influenciam a economia no mundo. Organizacionalmente, o uso de estratégias sustentáveis é capaz de trazer retornos em prol de um desenvolvimento saudável e de uma cultura consciente quanto aos desperdícios, além de refletir na forma como as organizações mantém seu relacionamento com a sociedade e o meio ambiente. O objetivo deste trabalho é propor um modelo para a priorização de estratégias que apoiem a criação de um ambiente e uma cultura baseados em sustentabilidade nas organizações. Tal modelo possui quatro etapas, iniciando-se com a estruturação de problemas, passando pela definição de critérios e alternativas, aplicação de método multicritério para priorização e, por fim, chegando à implementação das alternativas de acordo com o que o decisor julgue adequado, tomando por base o resultado da priorização.

The supply chain (SC) integrates the process management of the target enterprise, providing a connection with their clients, suppliers and within itself. This type of management is dynamic and it covers the business processes that involve since the final consumer to the primary suppliers which provide products, services and information that generate value to the consumers and stakeholders. Given the importance of the integration of these processes on a SC, this paper’s objective is to elaborate a diagnosis to evaluate, and propose improvements relating to processes Management throughout the Supply Chain Management (SCM) based on the model by Lambert et al. (1998) as well as through a SWOT analysis. The present research has utilized a qualitative approach, adjusted to exploratory adapted to a case study applied on a company of the textile industry located on the wasteland region of Pernambuco state, and was conducted through personal interviews by the means of an elaborate questionnaire. The results show that there is a lack of process management models, which is a compromising factor to the efficiency of the processes involved on the SCM, as well as also show the need of formalization of the key-processes on the supply line.

Purpose: To introduce a nonliving microvascular training model based on vessels diameter and feasibility. Methods: We dissected ten oxen tongues, and divided the pedicles into three-thirds: proximal, middle and distal. We measured the external vessels diameter in all regions. We performed a descriptive statistical analysis. Three students (two beginner level and one intermediate level) performed this training. We evaluated the confidence, according Likert scale. Results: We dissected all oxen tongues, each tongue showed two parallel pedicles. Each pedicle was located at 1.5 - 2.0 cm from the midline. Proximal median artery and vein diameter were 3.9 ± 0.7, and 5.04 ± 1.44mm, respectively. In the middle third, the mean artery diameter was 3.3 ± 0.4mm, and the vein diameter was 3.5 ± 0.9mm. The distal third showed a mean artery diameter of 2.0 ± 0.42mm, and a vein diameter of 2.4 ± 0.82mm. The students performed ten anastomoses. This study showed a higher confidence level (CL) (p=0.03) than the pre training CL assessment. Conclusion: This study suggested a feasible non-animal model for microsurgical training process for beginners and intermediate trainees.

Human resource allocation (HRA) can be viewed as core processes of the project management of information systems. Both in organizations, the business of which is to provide solutions for Information Systems, as in units of companies that work with Information Systems (IS), there are frequent demands for human resources to be allocated to IS projects. However, this is not a simple task and becomes more complex as the numbers of projects and professionals, including the range of expertise required, increase. This paper presents a methodology, based on dynamic programming, to assign human resources to software development projects. The methodology takes into account the complexity of each project and the existing capabilities of staff and the skills required for the project. A simulation is used to demonstrate the decision model.

Objective To investigate the relationship between total and segmental body fat, bone mineral density and bone mineral content in undergraduate students stratified according to nutritional status. Methods The study included 45 male undergraduate students aged between 20 and 30 years. Total and segmental body composition, bone mineral density and bone mineral content assessments were performed using dual energy X-ray absorptiometry. Subjects were allocated into three groups (eutrophic, overweight and obese). Results With the exception of upper limb bone mineral content, significantly higher (p

This study aims to analyze the failures of the activity of project management in small and mediumsizedhigh-tech firms, using the tool PRISM. This postmortem methodology, proposed by Gary Pan,Shan L. and Ray Hackney Pan, analyzes the interactions between the components of the projectduring the exchange relationship between the project organization, information system and theusers. Thus, the contribution of this work is to allow a formal analysis of the relationship betweenthe sequence of events development projects into an innovative view, that provide insights into thepotential success or failure of the project on medium-sized high-tech firms (whose the acronym is PMET)., Este estudo de caso tem o objetivo de analisar as falhas da atividade de gerenciamento de projetos em pequenas e médias empresas de alta tecnologia, utilizando a ferramenta PRISM. Essa metodologia, proposta por Gary Pan, Ray Hackney e Shan L. Pan, analisa as interações post mortem entre os componentes do projeto durante o curso de sua execução como uma relação de intercâmbio entre a organização do projeto, o sistema de informação e os seus usuários. Assim, a contribuição desse trabalho é permitir uma análise formal das relações entre a sucessão de eventos de desenvolvimento de projetos de cunho inovativo e fornecer insights sobre o sucesso potencial ou o fracasso em projetos de pequenas e médias empresas de alta tecnologia (PMET).DOI:10.5585/gep.v2i1.32

Innovation has gained prominence and importance within organizations as a means of ensuring competitiveness. Innovation management is usually considered in order to improve the efficiency of internal administrative processes in organizations. However, it may not be considered as a single and well-structured decision making problem, since it involves the need to aggregate different experts' points of view, and organizations' priorities and constraints. Thus, this paper proposes the use a multicriteria decision making approach based on a combination of a problem structuring method and a noncompensatory multicriteria decision making method in order to prioritize actions to allow an Information Technology (IT) organization to acquire more efficiency in its processes and consequently increases its market share.

A vitamina A é essencial à preservação e ao funcionamento normal dos tecidos, assim como, ao crescimento e desenvolvimento. No humano há evidência indireta que a vitamina A em excesso, durante as primeiras semanas de gestação é teratogênica. Do contrário, não há dúvidas sobre os efeitos deletérios, de uma alimentação carente neste micronutriente e sobre a disponibilidade do conhecimento técnico para evitá-los. A preocupação com o fato de que a vitamina A conduziria a teratogenia em humanos, tem retardado a implementação de programas de combate a carência de vitamina A, atingindo principalmente os programas de enriquecimento de alimentos. A literatura é controvertida e dispõe de poucas informações sobre as doses para suplementação de gestantes. Como o retinol circulante materno é controlado homeostaticamente após o consumo de alimentos fonte de vitamina A, espera-se a mesma resposta metabólica após o consumo de alimentos fortificados, indicando que não há risco de teratogenia. Consequentemente, parece altamente improvável que o consumo de alimentos enriquecidos ou de suplementos de vitamina A pré-formada, nas doses unitárias habituais, tenha efeito teratogênico no homem. The vitamin A is essential to the preservation and the normal functioning of tissues, as well as, to the growth and development. In the human being it has indirect evidence that the vitamin A in excess, during the first weeks of gestation is teratogenic. Of the opposite, it does not have doubts on the deleterious effect, of a devoid feeding in this micronutrient and on the availability of the knowledge technician to prevent them. The concern with the fact of that the vitamin A would lead it the teratogenicity in human beings, has delayed the implementation of combat programs the vitamin A lack, mainly reaching the programs of food enrichment. Literature is controverted and makes use of few information on the doses for supplementation of pregnant. As retinol circulating maternal is controlled homeostatic after the food consumption vitamin source, it expects after same metabolic reply the strengthened food consumption, indicating that it does not have teratogenicity risk. Consequently, highly seems improbable that the consumption of enriched foods or vitamin supplements the daily pay-formed one, in habitual the single doses, has teratogenic effect in the man.

Family farming is one of the primary generators of work, employment and income in rural areas of Brazil. Based on this knowledge, the federal government has adopted incentives for producers in an attempt to make this productive sector more competitive and efficient. However, much remains to be done to make the development truly sustainable. By evaluating this dynamic, this paper proposes a model based on multimethodologies to assist the actors in defining and applying public policies. To facilitate and provide a greater understanding of the problem, the Strategic Options Development and Analysis (SODA) method was applied through cognitive maps in conjunction with the Strength, Weakness, Opportunities, Threats (SWOT) approach, which allowed a higher level of analysis of the alternatives. With the alternatives available, the multicriteria method PROMETHEE II was applied to ranking the alternatives to be implemented. The proposed model provides the people involved with a greater level of insight into the problem to be analysed and facilitates the adoption of public policies that meet the needs and preferences of farmers.

This paper presents a multicriteria methodology aimed at evaluating the quality of information technology (IT) projects. This assessment is derived from expert judgments regarding some aspects that are critical to project management. These criteria were obtained through a literature review and a questionnaire. For the development of this assessment fuzzy logic and multicriteria method SMARTS were used. In order to illustrate the application of the model a numerical example based on a hypothetical case is presented.

Investigar a associação entre o estado nutricional, e o desempenho das habilidades motoras, de idosos, cadastrados no Programa Saúde da Família, zona urbana, do município de Vitória de Santo Antão (PE). Estudo epidemiológico, transversal de campo do tipo descritivo-analítico. Participaram desta pesquisa 235 idosos com idade superior ou igual a 60 anos, do gênero masculino e feminino, residentes em Vitória (PE) e cadastrados nas unidades de saúde da família da zona urbana da cidade. O estado nutricional foi avaliado segundo o Índice de Massa Corporal e a Circunferência de Panturrilha. Para análise do desempenho motor foram utilizados quatro testes motores: Time Up&Go, Índice de Tinetti, Alcance Funcional e Apoio Unipodal. As associações foram verificadas segundo a correlação de Spearman. A associação do estado nutricional com os testes motores foi estatisticamente significativa entre os gêneros masculino* e feminino** (time up&go rho = 0,290*, 350**, alcance funcional rho = 0,232*, 352**, índice de Tinetti rho = 243*, 363** e apoio unipodal rho = 221*, 475**) não apresentando distinção entre sexo. A avaliação dos resultados mostrou associação entre o estado nutricional e a capacidade funcional entre os idosos independente do sexo; tendo sido a obesidade apontada como a condição nutricional limitante ao desempenho adequado nos testes. The scope of this paper was to investigate the relationship between the nutritional status and the motor skills of the elderly registered in the Family Health Program in the urban area of Vitória de Santo Antão in the State of Pernambuco, by means of a transversal epistemological descriptive-analytical field study. The participants of this survey were 235 elders, both male and female of 60-years-old and over registered in the family health program in the urban area of the city. The nutritional status was evaluated by the body mass index and the circumference of the calf. Four motor tests were used to evaluate motor performance: Time Up&Go, Tinetti's Index, Functional Reach and Unipodal Support. The associations were checked using Spearman's correlation. The association of the nutritional status with the motor tests was statistically significant among males* or females**: (Time Up&Go rho = 0.290* / 350**; Functional Reach rho = 0.232* / 352**; Tinetti's Index rho = 243* / 363** and Unipodal Support rho = 221* / 475**. The evaluation of the results revealed an association between nutritional status and functional capacity of the elders no matter what gender; with obesity being a limiting nutritional condition to adequate performance in the tests.

OBJETIVO: Esta pesquisa teve como objetivo avaliar a eficácia de flocos desidratados de abóbora na elevação dos níveis séricos de retinol e a resposta relativa à dose em pré-escolares. MÉTODOS: A ingestão de vitamina A foi avaliada por meio de inquérito dietético. Os flocos foram analisados quanto às características microbiológicas e ao conteúdo de carotenoides. As crianças estudadas receberam diariamente 6g do produto no almoço, durante 90 dias. Elas foram submetidas ao teste de resposta relativa à dose no início e no final do estudo. Amostras de sangue foram colhidas em jejum, para análise do retinol sérico por espectro-fotometria, no início do estudo, aos 30 dias de consumo e aos 90 dias. RESULTADOS: Quanto às análises microbiológicas, os flocos encontravam-se adequados para consumo. O nível médio de retinol sérico nas crianças aumentou de M=1,438, DP=0,45µmol/L (tempo 0) para M=1,659, DP=0,51µmol/L (30 dias) e M=1,928, DP=0,70µmol/L (90 dias). No início do estudo, 18,5% das crianças apresentavam níveis de retinol sérico abaixo do ponto de corte de 1,05µmol/L, proporção que caiu para 7,6% depois de 30 dias e para 0% após 90 dias. No final do período de estudo (90 dias) nenhuma criança apresentou resposta relativa à dose positiva. CONCLUSÃO: Os flocos de abóbora são eficazes na elevação do retinol sérico e na reserva hepática da vitamina em pré-escolares. OBJECTIVE: This study assessed the effectiveness of dehydrated pumpkin flakes for elevating serum retinol and the relative dose response in preschoolers. METHODS: Vitamin A intake was determined by dietary survey. The flakes were analyzed microbiologically and for carotenoid content. The children were then given 6 grams of flakes per day during lunch for 90 days. The relative dose response essay was done at baseline and end of intervention. Fasting blood samples were collected at baseline, 30 and 90 days to determine serum retinol levels by spectrophotometry. RESULTS: Microbiological analyses showed that the flakes were suitable for consumption. The mean serum retinol level of the children increased from M=1.438 (SD=0.45µmol/L) at baseline to M=1.659 (SD=0.51µmol/L) at 30 days and M=1.928 (SD=0.70µmol/L) at 90 days. At the beginning of the study, 18.5% of the children had serum retinol levels below 1.05µmol/L. This percentage dropped to 7.6% after 30 days and 0% after 90 days. At the end of the study period (90 days), no child had a positive relative dose response. CONCLUSION: Pumpkin flakes efficiently increase serum retinol levels and hepatic vitamin A reserves in preschoolers.

Serum vitamin A was determined before and 30-45 d after the administration of 60.6 mg (212 mumol) vitamin A to 544 Brazilian children residing in slum areas of Recife. The frequency-distribution curves were compared in a subgroup of children whose vitamin A status was assessed initially by the relative-dose-response (RDR) test. The curves of children with negative (adequate status) and positive (inadequate status) RDR tests were different. The difference disappeared after supplementation. The shape of the distribution curve after supplementation was close to normal with a mean, median, and 95% confidence interval of 1.78 +/- 0.49, 1.68, and 1.02-2.90 mumol/L, respectively. The postsupplementation curve derived from this underprivileged child population may serve as a reference for diagnostic, surveillance, and program-evaluation purposes.

The Relative Dose Response Test (RDR) was used to assess the bioavailability of vitamin A in a stabilized form in artificially produced rice kernels. The vitamin A proved stable to storage and cooking, and the enriched rice was nontoxic, and had the same sensory characteristics of ordinary rice. The nutrified rice, cooked with sugar and milk, was offered to 83 deprived children as the challenge dose for an RDR test. The children showed positive and negative tests in agreement with their serum retinol levels. The regression of RDR on serum retinol levels was the same as that observed when the conventional RDR test was applied.

The effect of an infective episode of chickenpox on the vitamin A status of preschool-aged children was evaluated by use of the relative dose response (RDR) test. Status was determined before and 30, 120, and 180 d after administration ofa single oral high-dosage (200 000 LU) supplement of vitamin A. No differences in mean blood levels of retinol or per- centage ofchildren showing a positive RDR were apparent until after the infective episode that occurred '�'�-90 d after dosing. At 180 d postsupplementation, 74% of children who had been infected tested positive by the RDR, indicative of an inadequate liver reserve of vitamin A, in contrast to only 10% who had not been infected. Paired RDR observations at 0 and 180 d postsupplementation confirmed that the infective episode caused an accelerated depletion of liver reserves ofvitamin A. Am J Clin Nuir 1987;46:9l-4.

Vitamin A status was determined using fasting plasma levels and the relative dose response (RDR) procedure before and 30, 120, and 180 days after administration ofan oral massive (200,000 lU) dose of vitamin A. The study was carried out in Recife, Brazil among 93 children of 7 yr or less from low income families who attended two day-care programs. The RDR procedure is conducted by obtaining a fasting blood (Ao), feeding 450 retinol equivalents and obtaining a second blood specimen after 5 h (A5). The RDR-(As-Ao)/A5 X 100. A single massive oral dose of vitamin A was given after conducting the base-line RDR test. The RDR procedure was repeated at 30, 120, and 180 days. Weight and height measurements were obtained at each observation and the bloods were analyzed for Hb, total protein, and serum iron, as well as vitamin A. Serum albumin was determined in 120- and 180-day bloods. Serum iron levels were improved 30 days after supplementation with the massive dose of vitamin A. The RDR procedure was found practical to apply in mildly undernourished children under nonclinical condition. In this group of low income children presumed to be habitually ingesting minimally adequate diets, a serum vitamin A level of 20 �zg/dl or less invariably was associated with an elevated RDR test. Blood levels between 20 to 40 ig/dl were not consistently predictive of the RDR response. All elevated RDR tests reverted to normal after supplementation with vitamin A, presumably indirectly indicating a presupplementation inadequate vitamin A status. Hence, the RDR was a more sensitive indicator of inadequate vitamin A status than was only a serum level of vitamin A when blood levels were above 20 �g/dl. The procedure may have applicability in assessment of marginal vitamin A status of free-living individuals, among subsamples in population surveys and as a means of assessing the efficacy of vitamin A intervention pro- grams. Am J Clin Nutr 1984:40:1281-1289.