LUZ
Maracaibo, Venezuela
LUZ
Maracaibo, Venezuela

Time filter

Source Type

Lereico R.,University of Zulia | Velasco J.,LUZ | Gonzalez B.,University of Zulia | Martinez M.,LUZ | Perez J.,Institute Investigaciones
Revista de la Facultad de Agronomia | Year: 2014

The aim of this research is to characterize the management process of the sorghum farmers in Zulia state, in order to know how these farmers manage and lead their farms and their management implications in the use of the resources and the productive and economic outcome. The design of this research is related to non-experimental field, and descriptive theory based on the systems approach. The sample selected through stratified random sampling with proportional allocation corresponds to 37 farms located in the municipalities of Zulia state: Mara, Páez, Jesús Enrique Lossada, La Cañada de Urdaneta, Miranda and Baralt. A structured survey was used joined with direct observation and literature review. The data were grouped into one Excel spreadsheet using a matrix and analyzed using the statistical package SPSS v. 19.0. Five management levels were identified within sorghum farmers with their particular characteristics according to indices related to the dimensions of Management. Finally, several lines of action were found in order to improve the management process of sorghum farmers. One conclusion of this research is that the management process that sorghum farmers make on their farms depends on the own experiences about productive process of sorghum. © 2014 Universidad del Zulia. All rights reserved.


Guerrero R.,University of Zulia | Hernandez C.,University of Zulia | Chacin J.,University of Zulia | Clamens C.,University of Zulia | Bracho B.,LUZ
Revista de la Facultad de Agronomia | Year: 2014

The preliminary aspects of the floral biology of Anacardium occidentale L. (cashew) were evaluated in red and yellow cultivars and clones (Embrapa CCP-1001 and Embrapa CCP-76). The methodology of Raimundez and Hokche was used. Hermaphrodite and staminate flowers, presented five green and pubescent sepals and five white petals when they are newly opened and then are pink. The gynoecium had a sunilocular and uniovular ovary and the androecium had seven small anthers and one anther longer than the rest, all ditecas. The anthesis of the staminate flowers was between 1:00-3:00 pm and the hermaphrodite flowers were observed between 10:00 am and 03:00 pm. The pollen is simple convex and reticulated. The floral biology is essential to the agronomic management of the species. © 2014, Universidad del Zulia. All rights reserved.


Moreno Quintero R.J.,University of Zulia | Melean Romero R.A.,LUZ | Bonomie Sanchez M.E.,LUZ
Agroalimentaria | Year: 2011

The complex process of transformation of poultry industry in the Zulia region of Venezuela and the amplitude of this value chain require determining management policies oriented to management of stocks (inventories), as a key element to ensure continuity on its operations. In this sense, the aim of this paper is to analyze the inventory management in the poultry company La Rosita S.A. (AVIROSA) case. Thus, first of all, the authors identified all the types of inventory used by the organization; and, afterwards, the policies implemented for planning and control of these assets were studied. A descriptive methodology under a non-experimental approach was used, based on secondary sources and also primary data collection; this latter were obtained through a questionnaire in the form of surveys, as well as in-depth interviews with key people working inside the organization. Main results indicate that the company uses raw materials, work-in-process and finished goods inventories in various stages of the value chain; moreover, planning policies and control to this area are flexible and defined in terms of two factors: 1) internal changes made in the production process, and 2) external requirements demanded by the market. It concludes that an irregular management of inventories of raw materials, work-in-process and finished goods has been applied during the supply chain; additionally, the inventory policies are not accurately systematized for compliance; instead, these policies are determined by personal experience in the poultry industry.


Sanchez-Urdaneta A.B.,University of Zulia | Benedetelli E.U.,LUZ | Bastardo M.,LUZ | Mavarez C.,LUZ | And 2 more authors.
Revista de la Facultad de Agronomia | Year: 2014

Cujies (bayahonda) are legumes recognized as representative of Venezuela. They are used as fodder, timber and as ornamentals. The objective of the research was to characterize morphologically and develop a key for the identification and recognition of bayahonda present at University of Zulia. Through tours at the university campus it is determined the presence of species Prosopis juliflora, Vachellia macracantha, V. tortuosa, Pithecellobium dulce, Calliandra falcata (Mimosaceae), Parkinsonia aculeata and Cercidium praecox (Caesalpiniaceae). A completely split plot randomized design was used, with 20 replications per plant. Length (LFL) and width of the leaflets (WFL), length (LFLL) and width leaflets (WFLL), pair number of leaflets (NPL) length (LLB) and width of the leaf blade (WLB) leaflets were determined per sheet (NPFLS), length of spines (LS), length (LFR) and width of fruit (WFR) and polar diameter (PD) and equatorial seeds (ED) were determined. Statistical differences were found due to the kind of cuji (P>0.001) for all variables. The 85.15% of the variation was explained by three main components. The cluster analysis allowed the formation of four groups. The results showed a high variability between these two families of plants and helped to develop a key based on morphological characters for easy recognition of the species. © 2014, Universidad del Zulia. All rights reserved.


Montero-Quintero K.C.,LUZ | Montero-Quintero K.C.,University of Cordoba, Spain | Moreno-Rojas R.,University of Cordoba, Spain | Ali Molina E.,LUZ | And 4 more authors.
Interciencia | Year: 2015

Amaranth is a plant rich in protein, minerals and fiber that could be used in food processing. We evaluated physical carateristics and chemical composition of bread with 0, 5, 10, 15 and 20% of Amaranthus dubius Mart. ex Thell and thereafter two breads were selected for biological evaluation. Thirty Sprague Dawley rats were divided into five groups: bread diet with 0% amaranth (DPA0), bread diet with 10% amaranth (DPA10), bread diet with 20% of amaranth (DPA20) casein diet (DC) and aproteic diet. A randomized design was used univariate and the multiple comparison Tukey test was applied, with six replicates and three subsamplings. The highest content of protein, crude fiber and minerals was found in breads with 10 and 20% amaranth, showing statistical differences (P < 0.05) between them and the other breads. Feed intake, feed efficiency and weight gain showed no statistical differences (P>0.05) between diets with amaranth. DPA10 digestibility was higher, without statistical difference (P>0.05) with DC. The bread with 10% amaranth presented the best physical characteristics and proximal composition, especially proteins, lipids and mineral, and high digestibility. The use of amaranth flour up to 10% is an alternative to improve the nutritional value of the bread and prepare functional foods for fiber intake. © 2015, Interciencia Association. All rights reserved.


With a view to designing general structures for accounting of costs in production systems of dual purpose in Táchira State, was carried out a research of projective type design field, expostfacto, contemporary transactional and study of traits in north and south areas of Táchira state. The technique of survey by questionnaire instrument was used; this was applied to 109 producers. Descriptive statistics and cluster analysis used to characterize systems according to the technology used and intent of the same. 4 groups were with differences in average values of components for technology: minimal, basic, medium and high, and two systems according to intentionality: cow-calve and cow-bull. Generally, the most important elements of cost are labour, food and medicines, less productive technological groups are minimal and high and, most productive medium group which coincides with larger farms with increasing use of machinery. 78% of the total farms, is dedicated to the production and sale of milk and calves at weaning distributed in 4 technology groups. The proposed accounting structures vary depending on the application of management strategies in each technology group, the capitalization costs (historical cost attached to the theory of costs by absorption) is warranted in cases in which work with systems cow-calves (prenatal costs and breeding centers) or cow-bull (prenatal cost centers, parenting, levanter, fattening).


In the western of Venezuela, in an area characterized as very dry tropical forest, an experiment was conducted in order to evaluate the defoliation frequency effect on yield of dry matter (DM) of botanical fractions of purple King grass (Pennisetum purpureum x Pennisetum typhoides). It was determined the yield of DM in leaves (DMSH, g.plant-1), internodes (DMSE, g.plant-1), nodes (DMSN, g.plant-1), total (DMST, g.plant-1) and leaf: Stem (RHT) under three defoliation frequencies (30, 45 and 60 days). A completely randomized design was used with seven replications. The results showed a significant effect (P<0.05) in the frequency on DMSH, DMSE, DMSN and DMST, while it did not affect the RHT. The highest yields of DM botanical fractions were obtained when the plants were harvested every 60 days (170.4, 32.5, 7.52 and 210.43 g.plant-1 for DMSH, DMSE, DMSN and DMST, respectively). The RHT gained an average of 7.25. The largest proportion in the composition of the plant was leaf (86.98%) followed by internodes (10.14%) and knots (2.88%). The best behavior of the purple king grass was obtained when the plants were harvested to 60 days. © 2015 Universidad del Zulia. All rights reserved.


Hernandez-Araujo J.A.,University of Zulia | Gasco Guerrero G.,Technical University of Madrid | Marmol L.,LUZ | Barcenas J.,LUZ | Polo V.,LUZ
Revista de la Facultad de Agronomia | Year: 2013

Soil is a live element filled with a biodiversity, making it one of the essential ecosystems for life. For misuse have been blighted for many soil salinization. The objective was to evaluate the bioremediation of a soil with salt problems with the application of two proportions [1.5 and 3% (w/w)] of three organic amendments: compost, vermicompost and Lemna solid blend or not with 100% the requirement of phosphogypsum, generating 15 treatments. The evaluation was conducted in simulated soil columns incubated with organic materials, compost and vermicompost were processed with the use of cow manure, Lemna was recollected from the shores of Maracaibo's Lake. Significant differences (P<0.05) between treatments for the variable electrical conductivity, sodium absorption ratio and exchangeable sodium percentage, there were no differences between the proportions and the use of phosphogypsum. The material with less potential for bioremediation was the Lemna by its high contents of Na+. The methodology of simulated soil columns under the study conditions was entirely appropriate to evaluate the bioremediation driven into the ground to control the effect of water application. Also, there was recovery of the product of its reduction in the content of salts, its recovery was higher in those amended with Lemna. The amendment vermicompost at 1.5% is recommended for bioremediation of soils affected by salts.


Zavrtanik J.,LUZ | Pogacnik A.,Fakulteta za gradbenistvo in geodezijo
Geodetski Vestnik | Year: 2012

Notwithstanding the impression that the pressure on land is decreasing because of the current economic crisis, the challenge of a contemporary urban planning to involve all stakeholders as equally as possible in the planning process remains unchanged. This article focuses on the acceptability of the integration private initiatives into the decision-making process. It asserts that urban planning based on private initiative does not lead to a sustainable spatial development; furthermore, the existing criteria-based land development approach does not necessarily give optimal results.


Chacin-Bonilla L.,University of Medical Sciences of Costa Rica | Chacin-Bonilla L.,Institute Investigaciones Clinicas | Barrios F.,LUZ | Cheng-Ng R.,LUZ
Interciencia | Year: 2010

The present paper is a review of the sources and transmission mechanisms of Cyclospora cayetanensis, an emergent coccidian pathogen that causes endemic and epidemic diarrheal illness worldwide. The epidemiology of the infection is not well known. Humans appear to be the only natural hosts. However, the role of animals as natural reservoirs of C. cayetanensis remains to be determined. Transmission of the parasite occurs through an environmental vehicle. In developing countries, cyclosporosis has been associated with contaminated water or foods, contact with soil or animals, and variables related with low socioeconomic status. In industrialized countries, the infection has been linked to traveller's diarrhea and numerous high profile foodborne outbreaks have been associated with imported fresh produce from endemic areas. Waterborne epidemics have also been reported to a lesser extent. Increasing globalization of fresh food supply and international travel have contributed to the spread of C. cayetanensis from endemic to non-endemic areas. The existence of several uncertainties in the routes of transmission and other epidemiologic aspects of the parasite highlight the need for continued research in several aspects of the epidemiology of the infection. In conclusion, transmission of C. cayetanensis occurs through environmental vehicles such as water, food and soil. However, the relative importance of the various sources and transmission routes remains unknown.

Loading LUZ collaborators
Loading LUZ collaborators