Universitas Scientiarum

<font color="#000080">Universitas Scientiarum (Univ. Sci.) is registered at the ISSN National Centre (ISSN 0122-7483 printed version, ISSN 2027-1352 online version) and indexed in Scopus, Chemical Abstracts (CA), SciELO, Google scholar, ULRICHS-WEB, Latindex, Periódica, Redalyc, Indice Bibliográfico Nacional (Publindex), and Directory of Open Access Journals (DOAJ). Universitas Scientiarum is a refereed scientific journal and is edited at the Faculty of Sciences of the Pontificia Universidad Javeriana (Bogotá, Colombia) and has been published continuously since 1987. Universitas Scientiarum publishes original papers, reviews, brief communications, editorials, letters to the Editor, and reviews of books, handbooks and meetings. The journal receives manuscripts in Spanish, Portuguese or English. The journal will accept papers on any subject of natural, physical or exact sciences.<br></font><br>

List of Papers (Total 482)

Screening of polyketide genes from Brazilian Atlantic Forest soil

Soil is a large source of microorganisms with potential to produce bioactive compounds. Since most of them cannot be cultured, metagenomics has become a useful tool in order to evaluate this potential. The aim of this study was to screen biosynthetic polyketide genes (PKS) present in a metagenomic library constructed from a soil sample isolated from the Brazilian Atlantic Forest...

NiMo-sulfide supported on activated carbon to produce renewable diesel

Due to their weak polarity and large surface area, activated carbon supports have the potential to enhance the dispersion of metal-sulfides. It is expected that the absence of a strong metal-support interaction can result in the formation of a very active and stable Ni-Mo-S phase. In this study, catalysts with different amounts of nickel and molybdenum supported on a commercial...

Response Surface Methodology (RSM) for analysing culture conditions of Acidocella facilis strain USBA-GBX-505 and Partial Purification and Biochemical Characterization of Lipase 505 LIP

Using Response Surface Methodology (RSM) we evaluated the culture conditions (nitrogen source, carbon source, pH and agitation rate) that increase the biomass of Acidocellafaalis strain USBA-GBX-505 and therefore enhance the production of its lipolytic enzyme, 505 LIP. RSM results revealed that yeast extract and agitation were key culture factors that increased the growth...

Ex vivo model for studying polymicrobial biofilm formation in root canals

Endodontic disease has mainly a microbial origin. It is caused by biofilms capable of attaching and surviving in the root canal. Therefore, it is important to study the conditions in which those biofilms grow, develop and colonize the root canal system. However, few studies have used natural teeth as models, which would take into account the root canal anatomical complexity and...

Monitoring program for mammals in a protected area of Colombia

Between the second semester of 2009 and the first semester of 2011, camera traps were set up in conserved and disturbed habitats in the Otun Quimbaya Flora and Fauna Sanctuary. From a sampling effort of 2,066 camera-days, 673 photographs of 157 independent events were obtained for eight species of wild mammals and a domestic one. Their activity patterns were mainly nocturnal even...

Response Surface Methodology (RSM) for analysing culture conditions of Acidocella facilis strain USBA-GBX-505 and Partial Purification and Biochemical Characterization of Lipase 505 LIP

Using Response Surface Methodology (RSM) we evaluated the culture conditions (nitrogen source, carbon source, pH and agitation rate) that increase the biomass of Acidocellafaalis strain USBA-GBX-505 and therefore enhance the production of its lipolytic enzyme, 505 LIP. RSM results revealed that yeast extract and agitation were key culture factors that increased the growth...

Monitoring program for mammals in a protected area of Colombia

Between the second semester of 2009 and the first semester of 2011, camera traps were set up in conserved and disturbed habitats in the Otun Quimbaya Flora and Fauna Sanctuary. From a sampling effort of 2,066 camera-days, 673 photographs of 157 independent events were obtained for eight species of wild mammals and a domestic one. Their activity patterns were mainly nocturnal even...

Ex vivo model for studying polymicrobial biofilm formation in root canals

Endodontic disease has mainly a microbial origin. It is caused by biofilms capable of attaching and surviving in the root canal. Therefore, it is important to study the conditions in which those biofilms grow, develop and colonize the root canal system. However, few studies have used natural teeth as models, which would take into account the root canal anatomical complexity and...

Partial removal and detoxification of Malachite Green and Crystal Violet from laboratory artificially contaminated water by Pleurotus ostreatus.

The triphenylmethane Malachite Green (MG) and Crystal Violet (CV) dyes are cationic dyes and mix with domestic wastewater when dumped; increasing, among others, the chemical and biological oxygen demand and can cause acute toxicity at different trophic levels. Promoting the removal (decolorization) of MG and CV, and laccase activity (54.8 ± 8.9 and 30.6 ± 2.9 UL-1 respectively...

Apigenin glycoside: an antioxidant isolated from Alchornea coelophylla pax & k. Hoffm. (euphorbiaceae) leaf extract

An antioxidant flavonoid has been isolated from methanolic leaf extract of Alchornea coelophylla Pax & K. Hoffm. by means of different column chromatography steps with DIAION HP-20 resin and silica gel in combination with analytical highperformance liquid chromatography (HPLC). It was identified as Apigenin-8-C- (α-L-rhamnopyranosyl-(1-›2)-β-D-glucopyranoside) on the basis of...

De Sitter symmetries and inflationary scalar-vector models

In this paper, we study the correspondence between a field theory in de Sitter space in D-dimensions and a dual conformal field theory in a euclidean space in (D-1)-dimensions. In particular, we investigate the form in which this correspondence is established for a system of interacting scalar and a vector fields propagating in de Sitter space. We analyze some necessary (but not...

Characterization of recombinant human lysosomal beta-hexosaminidases produced in the methylotrophic yeast Pichia pastoris

β-hexosaminidases (Hex) are dimeric enzymes involved in the lysosomal degradation of glycolipids and glycans. They are formed by α- and/or β-subunits encoded by HEXA and HEXB genes, respectively. Mutations in these genes lead to Tay Sachs or Sandhoff diseases, which are neurodegenerative disorders caused by the accumulation of non-degraded glycolipids. Although tissue-derived Hex...

Characterization of recombinant human lysosomal beta-hexosaminidases produced in the methylotrophic yeast Pichia pastoris

β-hexosaminidases (Hex) are dimeric enzymes involved in the lysosomal degradation of glycolipids and glycans. They are formed by α- and/or β-subunits encoded by HEXA and HEXB genes, respectively. Mutations in these genes lead to Tay Sachs or Sandhoff diseases, which are neurodegenerative disorders caused by the accumulation of non-degraded glycolipids. Although tissue-derived Hex...

De Sitter symmetries and inflationary scalar-vector models

In this paper, we study the correspondence between a field theory in de Sitter space in D-dimensions and a dual conformal field theory in a euclidean space in (D-1)-dimensions. In particular, we investigate the form in which this correspondence is established for a system of interacting scalar and a vector fields propagating in de Sitter space. We analyze some necessary (but not...

Relationship between vitamin intake and total antioxidant capacity in elderly adults

The consumption of foods high in natural antioxidants, like fruits and vegetables, is associated with a lower risk of oxidative stress-related diseases. The aim of this study was to establish the relationship between the plasma antioxidant capacity in adults over fifty and their intake of vitamin A, C, and E. We evaluated 118 24-hour recalls of intake of foods. The intake of...

New record of Squalus cubensis Howell Rivero, 1936 (Chondrichthyes, Squalidae) in Colombia

Two Cuban dogfish Squalus cubensis (Squalidae) are recorded for the first time in the area of influence of Isla Fuerte, an island located at the limit of the southern continental shelf of the Colombian Caribbean. Additionally, it is the first capture report of this species in Colombia by artisanal fishery and at shallower catch depths than those reported in previous records. Due...

On the Activation of Quantum Nonlocality

We report on some quantum properties of physical systems, namely, entanglement, nonlocality, k-copy nonlocality (superactivation of nonlocality), hidden nonlocality (activation of nonlocality through local filtering) and the activation of nonlocality through tensoring and local filtering. The aim of this work is two-fold. First, we provide a review of the numerical procedures...

Entrapment of Rhizobium sp. by fluidized bed technique using polymers as coating materials

The spray-drying technique was applied for the development of three solid formulations of Rhizobium. Sodium alginate and hydroxypropyl methylcellulose (HPMC) with concentrations of 0.5 % were used as polymers. Results showed that none of the solid formulations had negative effects in vitro on the growth-promoting capacities of Rhizobium sp. G58 (p < 0.05). PCA's first three...