Universitas Scientiarum最新文献

{"title":"Thermo-kinetics of Forest Waste Using Model-Free Methods","authors":"A. Dhaundiyal, A. Mohammad, T. Laszlo","doi":"10.11144/JAVERIANA.SC24-1.TOFW","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC24-1.TOFW","url":null,"abstract":"Thermal behaviour of pine needles (Pinus Roxburghii) is examined through a thermogravimetry technique. The dried samples of pine needles undergo the non isothermal decomposition at temperature range of 308 - 1173 K. The heating rates used for experimental purposes are: 5 °C min-1, 10 °C min-1 and 15 °C min-1. Kinetic parameters of thermal decomposition reactions of pine needles are obtained through the model-free schemes. The estimated values of activation energy and frequency factor derived from Kissinger method are 132.77 kJ mol-1 and 13.15 x107 min-1, respectively. Furthermore, the averaged values of the same kinetics parameters retrieved from the isoconversional methods are 82.38 kJ mol-1 and 74.833 kJ mol-1, 25.42 x1013 min-1 and 13.449 x1010 min-1, respectively. Instead of the Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira Sunrose (KAS) schemes, the kinetic parameters derived from the Kissinger method are relatively promising for the thermal decomposition process, since the kinetic parameters are highly affected by intermediate stages and overlapping of the concurrent reaction occurred during pyrolysis.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC24-1.TOFW","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42349992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil macrofauna in areas with different ages after Pinus patula clearcutting","authors":"Esteban Tulande-M, J. I. Barrera-Cataño, C. Alonso-Malaver, Sofía Basto","doi":"10.11144/JAVERIANA.SC23-3.SMIA","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-3.SMIA","url":null,"abstract":"In Andean high montane areas, the establishment of exotic tree forests changes the soil dynamics and its biodiversity. Soil macrofauna act as indicators of ecosystem successional processes, and may have an important role in ecological restoration processes after clear cutting exotic tree plantations. The aim of the present study was to understand how soil macrofaunal assemblies change in areas with different ages post clear cutting of Pinus patula, and to identify the soil physico-chemical variables that better explain these variations. The macrofauna in a high montane forest was evaluated along with that of three areas with different ages post clearcutting: 0, 2.5, and 5 years after clearcutting (Yac). The effect of soil physico chemical variables on macrofauna abundance was also evaluated. Macrofauna composition changed after clearcutting. Macrofauna abundance, richness, and diversity were lower in the 0 Yac area than in the other areas. Moreover, the macrofuna similarity to the reference forest did not increase with the years after clearcutting. This is due to the changes in soil characteristics, triggered by clearcutting. Slope, temperature, bulk density, real density, loam, pH, P, Na and K were the soil variales with a positive effect on the macrofauna abundance. These physico-chemical variables should be considered when designing restoration plans for Andean forest ecosystems. Moreover, Diplopoda, Coleoptera and Chilopoda might be useful to monitor and evaluate restoration processes after Pinus spp. clearcutting, because of their high abundance, diversity and relationship with environmental conditions.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-3.SMIA","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48904941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel textile wastewater treatment using ligninolytic co-culture and photocatalysis with TiO2","authors":"Andrea Blanco-Vargas, Christian Fernando Ramírez-Sierra, Marcela Duarte Castañeda, Milena Beltrán-Villarraga, L. K. Medina-cÓrdoba, A. Florido-Cuellar, J. Cardona-Bedoya, María Claudia Campos-Pinilla, A. M. Pedroza-Rodriguez","doi":"10.11144/JAVERIANA.SC23-3.ANTW","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-3.ANTW","url":null,"abstract":"Textile industries produce effluent waste water that, if discharged, exerts a negative impact on the environment. Thus, it is necessary to design and implement novel waste water treatment solutions. A sequential treatment consisting of ligninolytic co-culture with the fungi Pleurotus ostreatus and Phanerochaete crhysosporium (secondary treatment) coupled to TiO2/UV photocatalysis (tertiary treatment) was evaluated in the laboratory in order to discolor, detoxify, and reuse textile effluent waste water in subsequent textile dyeing cycles. After 48 h of secondary treatment, upto 80 % of the color in the waste water was removed and its chemical and biochemical oxygen demands (COD, and BOD5) were abated in 92 % and 76 %, respectively. Laccase and MnP activities were central to color removal and COD and BOD5 abatement, exhibiting activity values of 410 U.L-1 and 1 428 U.L-1, respectively. Subjecting waste water samples to 12h of tertiary treatment led to an 86 % color removal and 73 % and 86 % COD and BOD5 abatement, respectively. The application of  a sequential treatment for 18 h improved the effectiveness of the waste water treatment, resultingin 89 % of color removal, along with 81 % and 89 % COD and BOD5 abatement, respectively. With this sequential treatment a bacterial inactivation of 55 % was observed. TiO2 films were reused continuously during two consecutive treatment cycles without thermic reactivation. Removal percentages greater than 50 % were attained. Acute toxicity tests performed with untreated waste water led to a lethality level of 100 % at 50 % in Hydra attenuata and to a growth inhibition of 54 % at 50 % in Lactuca sativa. Whereas sequentially treated waste water excreted a 13 % lethality at 6.25 % and aninhibition of 12 % at 75 % for H. attenuata and L. sativa, respectively. Finally, sequentially treated waste water was reused on dyeing experiments in which 0.86 mg.g-1 adsorbed dye per g of fabric, that is equivalent to 80 % of dye adsorption.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-3.ANTW","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43882526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cellulases production on paper and sawdust using native Trichoderma asperellum","authors":"Y. Zapata, Angelica Galviz-Quezada, Víctor Manuel Osorio Echeverri","doi":"10.11144/Javeriana.SC23-3.cpop","DOIUrl":"https://doi.org/10.11144/Javeriana.SC23-3.cpop","url":null,"abstract":"Microbial cellulases are industrially used enzymes that catalyze the cleavage of the glycosidic bonds of cellulose. This hydrolysis yields sugars that can be used in processes such as bioethanol production. These enzymes are mainly produced by fungi belonging to the genus Trichoderma via submerged or solid state fermentation with cellulosic materials as substrates. Recent publications have increasingly demonstrated that alternatives to T.reesei enzymes in the production of second generation biofuels exist. Here, cellulolytic activities of crude extracts obtained from a native isolate of T.asperellum from coffe pulp and a strain of T.reesei were evaluated. Solid state fermentations were performed using paper and sawdust as substrates. The activities were measured after 12 days of incubation. The extracts obtained from T.reesei showed higher cellulase and endoglucanase activities (6.5 and 5.8 U/g) than those obtained using T.asperellum (5.6 and 4.1 U/g) with paper as substrate. There were no significant differences between isolates when grownon sawdust. It was possible to verify that native T.asperellum was able to produce cellulases on lignocellulosic material such as moistened paper and sawdust without having undergone a chemical pretreatment.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/Javeriana.SC23-3.cpop","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47158612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Decreased rotavirus infection of MA104 cells via probiotic extract binding to Hsc70 and ß3 integrin receptors","authors":"S. P. Salas-Cárdenas, N. N. Olaya-Galán, K. Fernández, F. Velez, C. Guerrero, M. Guitierrez","doi":"10.11144/JAVERIANA.SC23-2.DRIO","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-2.DRIO","url":null,"abstract":"Probiotic bacteria are microorganisms beneficial to human health, useful to improving biological conditions. Thanks to probiotic bacteria the symptoms of viral infections can be alleviated. Different mechanisms whereby probiotic bacteria exert they antiviral effect have been proposed. The aim of this study was to determine whether probiotic bacteria extracts bind to receptors of host cells susceptible of rotavirus (RV) infection. To accomplish this objective, four probiotic bacterial strains of Lactobacillus spp. and Bifidobacterium spp. were tested. Probiotic extracts were obtained after bacterial growth, cell lysis and centrifugation. Obtained probiotic extracts were used in assays to interfere with adhesion and penetration of a RV strain in the mammal cell line MA104. Furthermore, the interaction between probiotic extracts and MA104 cell receptors was evaluated by co-immunoprecipitation assays using anti-ß3-integrins and anti-Hsc70 antibodies. All four probiotic, protein-rich, extracts reduced RV infections in MA104 cells, suggesting a successful antiviral activity mediated by these probiotic extracts. All probiotic extracts significantly exerted thir antiviral activity by interfering with RV adhesion on MA104 cell receptors, with proteins in probiotic extracts competitively interacting with cell surface receptors necessary to RV infection. Co-immunoprecipitation assay results showed that proteins in probiotic extracts were able to bind to ß3-integrinsand Hsc70, which are two cellular receptors required to viral infection. The most significant contribution of this study is an insight into the mechanisms of probiotic antiviral activity, thus expanding current probiotics fundamental knowledge.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-2.DRIO","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49084214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Pareto Compliance of the Averaged Hausdorff Distance as a Performance Indicator","authors":"Andrés Vargas","doi":"10.11144/JAVERIANA.SC23-3.OTPC","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-3.OTPC","url":null,"abstract":"The averaged Hausdorff distance ∆p is an inframetric, recently introduced in evolutionary multiobjective optimization (EMO) as a tool to measure the optimality of finite size approximations to the Pareto front associated to a multiobjective optimization problem (MOP). Tools of this kind are called performance indicators, and their quality depends on the useful criteria they provide to evaluate the suitability of different candidate solutions to a given MOP. We present here a purely theoretical study of the compliance of the ∆p -indicator to the notion of Pareto optimality. Since ∆p is defined in terms of a modified version of other well- known indicators, namely the generational distance GDp , and the inverted generational distance IGDp , specific criteria for the Pareto compliance of each one of them is discussed in detail. In doing so, we review some previously available knowledge on the behavior of these indicators, correcting inaccuracies found in the literature, and establish new and more general results, including detailed proofs and examples of illustrative situations.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-3.OTPC","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49208257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the mRNA untranslated regions [UTR] of the Trypanosoma cruzi LYT1 isoforms derived by alternative trans-splicing","authors":"Elizabeth Ruiz, C. Ramírez, J. Casas, María Isabel Ospina, J. M. Requena, C. Puerta","doi":"10.11144/JAVERIANA.SC23-2.COTM","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-2.COTM","url":null,"abstract":"In trypanosomatids, gene expression is mainly regulated at posttranscriptional level, through mechanisms based on the interaction between RNA Binding Proteins [RBPs] and motifs present in the untranslated regions [UTRs] of them RNAs, which altogether form ribonucleoproteic complexes [RNP] that define the fate of the mRNA. The pre-mRNA derived from the LYT1 gene of Trypanosoma cruzi, is processed by alternative trans-splicing, resulting in different mRNAs which code for the isoforms mLYT1 and kLYT1, proteins having differential expression, cellular location and function. The aim of this study was to characterize the 5’ and 3’ UTRs of the LYT1 mRNAs as the initial step towards the objective of identification of the RBPs responsible for their differential expression. The presence of the two types of 5’ UTRs were confirmed in two T. cruzi isolates belonging to the DTU I, thus, corroborating the occurrence of alternative trans-splicing also in the LYT1 gene of this T.cruzi DTU. In addition, for the first time, was unscovered the existence of two types of LYT1 mRNAs transcripts, differing in length by 116 nts, that are generated by alternative polyadenylation. Furthermore, an in-silico analysis of the experimentally obtained UTRs, and ten additional LYT1 sequences retrieved from TritrypDB and GenBank databases, together with a thoroughly search of structural motifs, showed a remarkable conservation of relevant structural motifs previously associated with RNA metabolism in the different UTRs; these elements might be involved in the differential stage-specific expression of each LYT1 isoform.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-2.COTM","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46484856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Swimming in Curved Surfaces and Gauss Curvature","authors":"L. Solanilla, W. O. Clavijo, Yessica P Velasco","doi":"10.11144/JAVERIANA.SC23-2.SICS","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-2.SICS","url":null,"abstract":"The Cartesian-Newtonian paradigm of mechanics establishes that, within an inertial frame, a body either remains at rest or moves uniformly on a line, unless a force acts externally upon it. This crucial assertion breaks down when the classical concepts of space, time and measurement reveal to be inadequate. If, for example, the space is non-flat, an effective translation might occur from rest in the absence of external applied force. In this paper we examine mathematically the motion of a small object or lizard on an arbitrary curved surface. Particularly, we allow the lizard’s shape to undergo a cyclic deformation due exclusively to internal forces, so that the total linear momentum is conserved. In addition to the fact that the deformation produces a swimming event, we prove –under fairly simplifying assumptions that such a translationis some what directly proportional to the Gauss curvature of the surface at the point where the lizardlies.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-2.SICS","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47632452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis, characterization and theoretical calculations of Cu(I) complex of trithiocyanuric acid [Cu(ttc)3]","authors":"Ximena Jaramillo-Fierro, C. Zambrano, F. Fernández, Regino Saenz-Puche, C. Costa, V. Guerrero, Silvia González","doi":"10.11144/JAVERIANA.SC23-2.SCAT","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-2.SCAT","url":null,"abstract":"A new Cu(I) complex constructed by reaction of trithiocyanuric acid (ttc) and copper (II) perchlorate hexahydrate has been successfully synthesized by a slow sedimentation method in a DMF solvent at room temperature. The molecular structure of the compound was elucidated by MALDI-TOFMS, UV Vis and FTIR spectroscopy, DSC-TGA analysis and magnetic susceptibility measurement. The proposed structure was corroborated by a computational study carried out with the Gaussian09 and AIMAII programs using the RB3LYP hybrid DFT functional with both 6-31G and Alhrich-TZV basis sets. The calculated vibrational frequencies values were compared with experimental FTIR values. Photophysical properties of the synthesized complex were evaluated by UV-Visible spectroscopy and compared with computed vertical excitation obtained from TDDFT. The theoretical vibrational frequencies and the UV Vis spectra are in good agreement with the experimental values. Additionally, the Frontier Molecular Orbitals (HOMO-LUMO) and the Molecular Electrostatic Potential of the complex was calculated using same theoretical approximation. The results showed the interaction between three coordinatedl igand atoms and the Cu(I) ion.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.11144/JAVERIANA.SC23-2.SCAT","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49564740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mass of Spiral Galaxies by Means of a Maximum Disc Model","authors":"Jerson Reina-Medrano, Framsol Lopez-Suspes, G. A. González","doi":"10.11144/JAVERIANA.SC23-2.MOSG","DOIUrl":"https://doi.org/10.11144/JAVERIANA.SC23-2.MOSG","url":null,"abstract":"Maximum disc mass models for a set of spiral galaxies from the Ursa Major Cluster are presented. We construct the models using the Hunther method and the particular solutions are chosen in such away that the circular velocities are adjusted very accurately to the observed rotation curves of some specific spiral galaxies. Under the maximum disc hypothesis, we consider that the rotation curves of the analyzed galaxies can be modeled with only the contribution of the disc. This implies that it is not necessary to consider the contribution of the dark matter halo in the inner part of the spiral. In this way, the models reproduce the global behavior of the rotation curves in the great majority of galaxies. Producing good adjustments to calculate the total mass of these galaxies, and yielding values of the order of 1010M0. Based on the verticalstability criterion presented by Viera & Ramos-Caro(2016), we find that all the galaxies analyzed present a vertically stable behavior.On the other hand, from the analysis of the epicyclic frequency we find that al lthe models exhibit mainly a radial stable behaviour except at the edge of the disc.","PeriodicalId":39200,"journal":{"name":"Universitas Scientiarum","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44196805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}