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Anteversión pélvica como causa de dolor lumbar, síndrome patelofemoral y dolores del crecimiento
(Ediciones Doyma, S.L., 2014-01-01) Vélez-Patiño, J.A.; Ríos-Sánchez, L.M.; Ochoa-Jaramillo, F.L.; Díaz-León, C.A.; Universidad EAFIT. Escuela de Ciencias; Modelado Matemático
Introduction: Back pain, patellofemoral syndrome and "growing pains" are increasingly common in children and adolescents, both with incidence and precocity of appearance. In most cases their etiology is unknown. Objective: The objective of this research was to explore the possible association of these three entities with pelvic anteversion. Methods: This is a cross-sectional study with case-control analysis, comprising a group of 30 symptomatic children aged between 6 and 17 years (cases) who had consulted for low back pain, "growing pains" or sore knees, and a control group of 30 children with no history of pain in these areas (controls). To measure the position of the pelvis and other biomechanical variables a software programme was developed that quantifies these measurements from reflective markings located on specific anatomical landmarks of each child. Other measurements were obtained through semiological tests and interviews with children and their parents. Results: Children and adolescents with pain had more pelvic anteversion compared with controls (mean 13.3 and 5.4 degrees, p < 0.001). They also had less strength in muscles: Lumbar extensor, abdominals, psoas and diaphragm. We found that psoas is the muscle most responsible for pelvis anteversion in symptomatic group. Compared with children without pain, those with back pain, patellofemoral syndrome or "growing pains" have 4.2 times more frequent poor or regular strength in the column extensor muscles. They also have nearly 18 times as likely to have a pelvic angle greater than 10 degrees compared with no pain children. Conclusions: Children and adolescents who suffer from back pain, patellofemoral syndrome and "growing pains" have increased pelvic anteversion and lower muscle strength, mainly in the thoracolumbar spine extensors, abdominals, diaphragm and psoas. The study found that the psoas muscle is most responsible for the development of pelvis anteversion. Pelvic anteversion is associated with low back pain, patellofemoral pain syndrome and "growing pains". © 2015 Arán Ediciones, S.L.
Bacillus subtilis EA-CB0575 genome reveals clues for plant growth promotion and potential for sustainable agriculture
(Springer, 2020-01-01) Franco-Sierra, N.D.; Posada, L.F.; Santa-María, G.; Romero-Tabarez, M.; Villegas-Escobar, V.; Álvarez, J.C.; Universidad EAFIT. Departamento de Ciencias; Biodiversidad, Evolución y Conservación
Bacillus subtilis is a remarkably diverse bacterial species that displays many ecological functions. Given its genomic diversity, the strain Bacillus subtilis EA-CB0575, isolated from the rhizosphere of a banana plant, was sequenced and assembled to determine the genomic potential associated with its plant growth promotion potential. The genome was sequenced by Illumina technology and assembled using Velvet 1.2.10, resulting in a whole genome of 4.09 Mb with 4332 genes. Genes involved in the production of indoles, siderophores, lipopeptides, volatile compounds, phytase, bacilibactin, and nitrogenase were predicted by gene annotation or by metabolic pathway prediction by RAST. These potential traits were determined using in vitro biochemical tests, finding that B. subtilis EA-CB0575 produces two families of lipopeptides (surfactin and fengycin), solubilizes phosphate, fixes nitrogen, and produces indole and siderophores compounds. Finally, strain EA-CB0575 increased 34.60% the total dry weight (TDW) of tomato plants with respect to non-inoculated plants at greenhouse level. These results suggest that the identification of strain-specific genes and predicted metabolic pathways might explain the strain potential to promote plant growth by several mechanisms of action, accelerating the development of plant biostimulants for sustainable agricultural. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
Bacillus subtilis EA-CB0575 genome reveals clues for plant growth promotion and potential for sustainable agriculture
(Springer, 2020-01-01) Franco-Sierra, N.D.; Posada, L.F.; Santa-María, G.; Romero-Tabarez, M.; Villegas-Escobar, V.; Álvarez, J.C.; Universidad EAFIT. Departamento de Ciencias; Ciencias Biológicas y Bioprocesos (CIBIOP)
Bacillus subtilis is a remarkably diverse bacterial species that displays many ecological functions. Given its genomic diversity, the strain Bacillus subtilis EA-CB0575, isolated from the rhizosphere of a banana plant, was sequenced and assembled to determine the genomic potential associated with its plant growth promotion potential. The genome was sequenced by Illumina technology and assembled using Velvet 1.2.10, resulting in a whole genome of 4.09 Mb with 4332 genes. Genes involved in the production of indoles, siderophores, lipopeptides, volatile compounds, phytase, bacilibactin, and nitrogenase were predicted by gene annotation or by metabolic pathway prediction by RAST. These potential traits were determined using in vitro biochemical tests, finding that B. subtilis EA-CB0575 produces two families of lipopeptides (surfactin and fengycin), solubilizes phosphate, fixes nitrogen, and produces indole and siderophores compounds. Finally, strain EA-CB0575 increased 34.60% the total dry weight (TDW) of tomato plants with respect to non-inoculated plants at greenhouse level. These results suggest that the identification of strain-specific genes and predicted metabolic pathways might explain the strain potential to promote plant growth by several mechanisms of action, accelerating the development of plant biostimulants for sustainable agricultural. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
Biomechanics of the canine mandible during bone transport distraction osteogenesis
(ASME, 2014-11-01) Zapata, Uriel; Dechow, Paul C.; Watanabe, Ikuya; Elsalanty, Mohammed E.; Opperman, Lynne A.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
This study compared biomechanical patterns between finite element models (FEMs) and a fresh dog mandible tested under molar and incisal physiological loads in order to clarify the effect of the bone transport distraction osteogenesis (BTDO) surgical process. Three FEMs of dog mandibles were built in order to evaluate the effects of BTDO. The first model evaluated the mandibular response under two physiological loads resembling bite processes. In the second model, a 5.0 cm bone defect was bridged with a bone transport reconstruction plate (BTRP). In the third model, new regenerated bony tissue was incorporated within the defect to mimic the surgical process without the presence of the device. Complementarily, a mandible of a male American foxhound dog was mechanically tested in the laboratory both in the presence and absence of a BTRP, and mechanical responses were measured by attaching rosettes to the bone surface of the mandible to validate the FEM predictions. The relationship between real and predicted values indicates that the stress patterns calculated using FEM are a valid predictor of the biomechanics of the BTDO procedures. The present study provides an interesting correlation between the stiffness of the device and the biomechanical response of the mandible affected for bone transport. Copyright © 2014 by ASME.
Biomechanics of the canine mandible during bone transport distraction osteogenesis
(ASME, 2014-11-01) Zapata, Uriel; Dechow, Paul C.; Watanabe, Ikuya; Elsalanty, Mohammed E.; Opperman, Lynne A.; Zapata, Uriel; Dechow, Paul C.; Watanabe, Ikuya; Elsalanty, Mohammed E.; Opperman, Lynne A.; Universidad EAFIT. Departamento de Ingeniería de Producción; Materiales de Ingeniería
This study compared biomechanical patterns between finite element models (FEMs) and a fresh dog mandible tested under molar and incisal physiological loads in order to clarify the effect of the bone transport distraction osteogenesis (BTDO) surgical process. Three FEMs of dog mandibles were built in order to evaluate the effects of BTDO. The first model evaluated the mandibular response under two physiological loads resembling bite processes. In the second model, a 5.0 cm bone defect was bridged with a bone transport reconstruction plate (BTRP). In the third model, new regenerated bony tissue was incorporated within the defect to mimic the surgical process without the presence of the device. Complementarily, a mandible of a male American foxhound dog was mechanically tested in the laboratory both in the presence and absence of a BTRP, and mechanical responses were measured by attaching rosettes to the bone surface of the mandible to validate the FEM predictions. The relationship between real and predicted values indicates that the stress patterns calculated using FEM are a valid predictor of the biomechanics of the BTDO procedures. The present study provides an interesting correlation between the stiffness of the device and the biomechanical response of the mandible affected for bone transport. Copyright © 2014 by ASME.
Ceratocystis cacaofunesta genome analysis reveals a large expansion of extracellular phosphatidylinositol-specific phospholipase-C genes (PI-PLC)
(BioMed Central Ltd., 2018-01-17) Molano, E.P.L.; Cabrera, O.G.; Jose, J.; do Nascimento, L.C.; Carazzolle, M.F.; Teixeira, P.J.P.L.; Alvarez, J.C.; Tiburcio, R.A.; Tokimatu Filho, P.M.; de Lima, G.M.A.; Guido, R.V.C.; Corrêa, T.L.R.; Leme, A.F.P.; Mieczkowski, P.; Pereira, G.A.G.; Universidad EAFIT. Departamento de Ciencias; Biodiversidad, Evolución y Conservación
Background: The Ceratocystis genus harbors a large number of phytopathogenic fungi that cause xylem parenchyma degradation and vascular destruction on a broad range of economically important plants. Ceratocystis cacaofunesta is a necrotrophic fungus responsible for lethal wilt disease in cacao. The aim of this work is to analyze the genome of C. cacaofunesta through a comparative approach with genomes of other Sordariomycetes in order to better understand the molecular basis of pathogenicity in the Ceratocystis genus. Results: We present an analysis of the C. cacaofunesta genome focusing on secreted proteins that might constitute pathogenicity factors. Comparative genome analyses among five Ceratocystidaceae species and 23 other Sordariomycetes fungi showed a strong reduction in gene content of the Ceratocystis genus. However, some gene families displayed a remarkable expansion, in particular, the Phosphatidylinositol specific phospholipases-C (PI-PLC) family. Also, evolutionary rate calculations suggest that the evolution process of this family was guided by positive selection. Interestingly, among the 82 PI-PLCs genes identified in the C. cacaofunesta genome, 70 genes encoding extracellular PI-PLCs are grouped in eight small scaffolds surrounded by transposon fragments and scars that could be involved in the rapid evolution of the PI-PLC family. Experimental secretome using LC-MS/MS validated 24% (86 proteins) of the total predicted secretome (342 proteins), including four PI-PLCs and other important pathogenicity factors. Conclusion: Analysis of the Ceratocystis cacaofunesta genome provides evidence that PI-PLCs may play a role in pathogenicity. Subsequent functional studies will be aimed at evaluating this hypothesis. The observed genetic arsenals, together with the analysis of the PI-PLC family shown in this work, reveal significant differences in the Ceratocystis genome compared to the classical vascular fungi, Verticillium and Fusarium. Altogether, our analyses provide new insights into the evolution and the molecular basis of plant pathogenicity. © 2018 The Author(s).
Ceratocystis cacaofunesta genome analysis reveals a large expansion of extracellular phosphatidylinositol-specific phospholipase-C genes (PI-PLC)
(BioMed Central Ltd., 2018-01-17) Molano, E.P.L.; Cabrera, O.G.; Jose, J.; do Nascimento, L.C.; Carazzolle, M.F.; Teixeira, P.J.P.L.; Alvarez, J.C.; Tiburcio, R.A.; Tokimatu Filho, P.M.; de Lima, G.M.A.; Guido, R.V.C.; Corrêa, T.L.R.; Leme, A.F.P.; Mieczkowski, P.; Pereira, G.A.G.; Universidad EAFIT. Departamento de Ciencias; Ciencias Biológicas y Bioprocesos (CIBIOP)
Background: The Ceratocystis genus harbors a large number of phytopathogenic fungi that cause xylem parenchyma degradation and vascular destruction on a broad range of economically important plants. Ceratocystis cacaofunesta is a necrotrophic fungus responsible for lethal wilt disease in cacao. The aim of this work is to analyze the genome of C. cacaofunesta through a comparative approach with genomes of other Sordariomycetes in order to better understand the molecular basis of pathogenicity in the Ceratocystis genus. Results: We present an analysis of the C. cacaofunesta genome focusing on secreted proteins that might constitute pathogenicity factors. Comparative genome analyses among five Ceratocystidaceae species and 23 other Sordariomycetes fungi showed a strong reduction in gene content of the Ceratocystis genus. However, some gene families displayed a remarkable expansion, in particular, the Phosphatidylinositol specific phospholipases-C (PI-PLC) family. Also, evolutionary rate calculations suggest that the evolution process of this family was guided by positive selection. Interestingly, among the 82 PI-PLCs genes identified in the C. cacaofunesta genome, 70 genes encoding extracellular PI-PLCs are grouped in eight small scaffolds surrounded by transposon fragments and scars that could be involved in the rapid evolution of the PI-PLC family. Experimental secretome using LC-MS/MS validated 24% (86 proteins) of the total predicted secretome (342 proteins), including four PI-PLCs and other important pathogenicity factors. Conclusion: Analysis of the Ceratocystis cacaofunesta genome provides evidence that PI-PLCs may play a role in pathogenicity. Subsequent functional studies will be aimed at evaluating this hypothesis. The observed genetic arsenals, together with the analysis of the PI-PLC family shown in this work, reveal significant differences in the Ceratocystis genome compared to the classical vascular fungi, Verticillium and Fusarium. Altogether, our analyses provide new insights into the evolution and the molecular basis of plant pathogenicity. © 2018 The Author(s).
Coagulation-flocculation sequential with Fenton or Photo-Fenton processes as an alternative for the industrial textile wastewater treatment
(Editorial Board, 2017-04-15) GilPavas, E.; Dobrosz-Gómez, I.; Gómez-García, M.Á.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de Procesos
In this study, the industrial textile wastewater was treated using a chemical-based technique (coagulation-flocculation, C-F) sequential with an advanced oxidation process (AOP: Fenton or Photo-Fenton). During the C-F, Al2(SO4)3 was used as coagulant and its optimal dose was determined using the jar test. The following operational conditions of C-F, maximizing the organic matter removal, were determined: 700 mg/L of Al2(SO4)3 at pH = 9.96. Thus, the C-F allowed to remove 98% of turbidity, 48% of Chemical Oxygen Demand (COD), and let to increase in the BOD5/COD ratio from 0.137 to 0.212. Subsequently, the C-F effluent was treated using each of AOPs. Their performances were optimized by the Response Surface Methodology (RSM) coupled with a Box-Behnken experimental design (BBD). The following optimal conditions of both Fenton (Fe2+/H2O2) and Photo-Fenton (Fe2+/H2O2/UV) processes were found: Fe2+ concentration = 1 mM, H2O2 dose = 2 mL/L (19.6 mM), and pH = 3. The combination of C-F pre-treatment with the Fenton reagent, at optimized conditions, let to remove 74% of COD during 90 min of the process. The C-F sequential with Photo-Fenton process let to reach 87% of COD removal, in the same time. Moreover, the BOD5/COD ratio increased from 0.212 to 0.68 and from 0.212 to 0.74 using Fenton and Photo-Fenton processes, respectively. Thus, the enhancement of biodegradability with the physico-chemical treatment was proved. The depletion of H2O2 was monitored during kinetic study. Strategies for improving the reaction efficiency, based on the H2O2 evolution, were also tested. © 2017 Elsevier Ltd
Coagulation-flocculation sequential with Fenton or Photo-Fenton processes as an alternative for the industrial textile wastewater treatment
(Editorial Board, 2017-04-15) GilPavas, E.; Dobrosz-Gómez, I.; Gómez-García, M.Á.; GilPavas, E.; Dobrosz-Gómez, I.; Gómez-García, M.Á.; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
In this study, the industrial textile wastewater was treated using a chemical-based technique (coagulation-flocculation, C-F) sequential with an advanced oxidation process (AOP: Fenton or Photo-Fenton). During the C-F, Al2(SO4)3 was used as coagulant and its optimal dose was determined using the jar test. The following operational conditions of C-F, maximizing the organic matter removal, were determined: 700 mg/L of Al2(SO4)3 at pH = 9.96. Thus, the C-F allowed to remove 98% of turbidity, 48% of Chemical Oxygen Demand (COD), and let to increase in the BOD5/COD ratio from 0.137 to 0.212. Subsequently, the C-F effluent was treated using each of AOPs. Their performances were optimized by the Response Surface Methodology (RSM) coupled with a Box-Behnken experimental design (BBD). The following optimal conditions of both Fenton (Fe2+/H2O2) and Photo-Fenton (Fe2+/H2O2/UV) processes were found: Fe2+ concentration = 1 mM, H2O2 dose = 2 mL/L (19.6 mM), and pH = 3. The combination of C-F pre-treatment with the Fenton reagent, at optimized conditions, let to remove 74% of COD during 90 min of the process. The C-F sequential with Photo-Fenton process let to reach 87% of COD removal, in the same time. Moreover, the BOD5/COD ratio increased from 0.212 to 0.68 and from 0.212 to 0.74 using Fenton and Photo-Fenton processes, respectively. Thus, the enhancement of biodegradability with the physico-chemical treatment was proved. The depletion of H2O2 was monitored during kinetic study. Strategies for improving the reaction efficiency, based on the H2O2 evolution, were also tested. © 2017 Elsevier Ltd
Cognitive behavioral therapy reduces illness perceptions and anxiety symptoms in patients with unruptured intracranial aneurysm
(Churchill Livingstone, 2020-01-01) Lemos M.; Román-Calderón J.P.; Restrepo J.; Gómez-Hoyos J.F.; Jimenez C.M.
The main purpose of this study was to assess the relation between cognitive behavioral therapy and possible changes in illness perceptions and anxiety in patients diagnosed with unruptured intracranial aneurysm. An observational study of an intervention with 67 patients with an unruptured intracranial aneurysm from two medical centers in a Colombian city (n = 35 on the intervention group) was carried out. To assess changes, measurements were taken at baseline and at one-year follow-up with the Beck Anxiety Inventory and the Illness Perception Questionnaire, brief version, taking into account the importance of perceptions in the process of adjusting to illness and acquiring healthy life habits. Hypotheses were tested by a structural model. The results obtained from this study showed that illness perceptions were related to anxiety levels at both time points; however, the relations were stronger before cognitive behavioral therapy (ßt0 = 0.61, p < 0.01; ßt1 = 0.37, p < 0.01). Cognitive behavioral therapy was found to be a moderator of changes in both illness perceptions and anxiety at the time of follow-up (ß = -0.31, p < 0.01; ß = -0.26, p < 0.01). The structural model suggests that cognitive behavioral therapy is associated with less anxiety (ß = -0.17, p < 0.05) and better illness perceptions (ß = -0.35, p < 0.01) in patients diagnosed with unruptured intracranial aneurysms. © 2020 Elsevier Ltd
Cognitive behavioral therapy reduces illness perceptions and anxiety symptoms in patients with unruptured intracranial aneurysm
(Churchill Livingstone, 2020-01-01) Lemos M.; Román-Calderón J.P.; Restrepo J.; Gómez-Hoyos J.F.; Jimenez C.M.; Lemos M.; Román-Calderón J.P.; Restrepo J.; Gómez-Hoyos J.F.; Jimenez C.M.; Universidad EAFIT. Departamento de Humanidades; Estudios en Psicología
The main purpose of this study was to assess the relation between cognitive behavioral therapy and possible changes in illness perceptions and anxiety in patients diagnosed with unruptured intracranial aneurysm. An observational study of an intervention with 67 patients with an unruptured intracranial aneurysm from two medical centers in a Colombian city (n = 35 on the intervention group) was carried out. To assess changes, measurements were taken at baseline and at one-year follow-up with the Beck Anxiety Inventory and the Illness Perception Questionnaire, brief version, taking into account the importance of perceptions in the process of adjusting to illness and acquiring healthy life habits. Hypotheses were tested by a structural model. The results obtained from this study showed that illness perceptions were related to anxiety levels at both time points; however, the relations were stronger before cognitive behavioral therapy (ßt0 = 0.61, p < 0.01; ßt1 = 0.37, p < 0.01). Cognitive behavioral therapy was found to be a moderator of changes in both illness perceptions and anxiety at the time of follow-up (ß = -0.31, p < 0.01; ß = -0.26, p < 0.01). The structural model suggests that cognitive behavioral therapy is associated with less anxiety (ß = -0.17, p < 0.05) and better illness perceptions (ß = -0.35, p < 0.01) in patients diagnosed with unruptured intracranial aneurysms. © 2020 Elsevier Ltd
Contributions of intermolecular bonding and lubrication to the mechanical behavior of a natural armor
(ELSEVIER SCI LTD, 2020-01-01) Jiang, H.; Ghods, S.; Weller, E.; Waddell, S.; Ossa, E.A.; Yang, F.; Arola, D.; Jiang, H.; Ghods, S.; Weller, E.; Waddell, S.; Ossa, E.A.; Yang, F.; Arola, D.; Universidad EAFIT. Departamento de Ingeniería de Producción; Materiales de Ingeniería
Among many dermal armors, fish scales have become a source of inspiration in the pursuit of “next-generation” structural materials. Although fish scales function in a hydrated environment, the role of water and intermolecular hydrogen bonding to their unique structural behavior has not been elucidated. Water molecules reside within and adjacent to the interpeptide locations of the collagen fibrils of the elasmodine and provide lubrication to the protein molecules during deformation. We evaluated the contributions of this lubrication and the intermolecular bonding to the mechanical behavior of elasmodine scales from the Black Carp (Mylopharyngodon piceus). Scales were exposed to polar solvents, followed by axial loading to failure and the deformation mechanisms were characterized via optical mechanics. Displacement of intermolecular water molecules by liquid polar solvents caused significant (p = 0.05) increases in stiffness, strength and toughness of the scales. Removal of this lubrication decreased the capacity for non-linear deformation and toughness, which results from the increased resistance to fibril rotations and sliding caused by molecular friction. The intermolecular lubrication is a key component of the “protecto-flexibility” of scales and these natural armors as a system; it can serve as an important component of biomimetic-driven designs for flexible armor systems. Statement of Significance: The natural armor of fish has become a topic of substantial scientific interest. Hydration is important to these materials as water molecules reside within the interpeptide locations of the collagen fibrils of the elasmodine and provide lubrication to the protein molecules during deformation. We explored the opportunity for tuning the mechanical behavior of scales as a model for next-generation engineering materials by adjusting the extent of hydrogen bonding with polar solvents and the corresponding interpeptide molecular lubrication. Removal of this lubrication decreased the capacity for non-linear deformation and toughness due to an increase in resistance to fibril rotations and sliding as imparted by molecular friction. We show that intermolecular lubrication is a key component of the “protecto-flexibility” of natural armors and it is an essential element of biomimetic approaches to develop flexible armor systems. © 2020 Acta Materialia Inc.
Cost-effectiveness analysis of thermotherapy versus pentavalent antimonials for the treatment of cutaneous leishmaniasis
(Blackwell Publishing, 2017-05-30) Cardona-Arias JA; López-Carvajal L; Tamayo Plata MP; Darío-Vélez I; Departamento de Humanidades; Estudios de Filosofía, Hermenéutica y Narrativas
Objective: The treatment of cutaneous leishmaniasis is toxic, has contraindications, and a high cost. The objective of this study was to estimate the cost-effectiveness of thermotherapy versus pentavalent antimonials for the treatment of cutaneous leishmaniasis. Methods: Effectiveness was the proportion of healing and safety with the adverse effects; these parameters were estimated from a controlled clinical trial and a meta-analysis. A standard costing was conducted. Average and incremental cost-effectiveness ratios were estimated. The uncertainty regarding effectiveness, safety, and costs was determined through sensitivity analyses. Results: The total costs were $66,807 with Glucantime and $14,079 with thermotherapy. The therapeutic effectiveness rates were 64.2% for thermotherapy and 85.1% for Glucantime. The average cost-effectiveness ratios ranged between $721 and $1275 for Glucantime and between $187 and $390 for thermotherapy. Based on the meta-analysis, thermotherapy may be a dominant strategy. Conclusion: The excellent cost-effectiveness ratio of thermotherapy shows the relevance of its inclusion in guidelines for the treatment. © 2017 Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd
Effect of chemical composition and microstructure on the mechanical behavior of fish scales from Megalops Atlanticus
(ELSEVIER SCIENCE BV, 2016-03-01) Gil-Duran, S.; Arola, D.; Ossa, E.A.; Gil-Duran, S.; Arola, D.; Ossa, E.A.; Universidad EAFIT. Departamento de Ingeniería de Producción; Materiales de Ingeniería
This paper presents an experimental study of the composition, microstructure and mechanical behavior of scales from the Megalops Atlanticus (Atlantic tarpon). The microstructure and composition were evaluated by Scanning Electron Microscopy (SEM) and RAMAN spectroscopy, respectively. The mechanical properties were evaluated in uniaxial tension as a function of position along the length of the fish (head, mid-length and tail). Results showed that the scales are composed of collagen and hydroxyapatite, and these constituents are distributed within three well-defined layers from the bottom to the top of the scale. The proportion of these layers with respect to the total scale thickness varies radially. The collagen fibers are arranged in plies with different orientations and with preferred orientation in the longitudinal direction of the fish. Results from the tensile tests showed that scales from Megalops Atlanticus exhibit variations in the elastic modulus as a function of body position. Additional testing performed with and without the highly mineralized top layers of the scale revealed that the mechanical behavior is anisotropic and that the highest strength was exhibited along the fish length. Furthermore, removing the top mineralized layers resulted in an increase in the tensile strength of the scale. © 2015 Elsevier Ltd.
The electrochemical elimination of coliforms from water using BBD/Ti or graphite anodes: A comparative study
(International Water Association Publishing, 2018-04-01) Gil Pavas, E.; Arbelaez, Paula Eliana; Medina, J.; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de Procesos
The elimination of total and fecal coliforms, from raw surface water, was carried out by electrochemical oxidation using either boron doped diamond (BDD/Ti) or graphite (GP) anodes, in a chloride-free medium. The optimal values of the operation parameters, maximizing the coliform elimination percentage, were determined using statistical experimental design. The current density ( j: 2-20 mA/cm2), the conductivity (s: 500-900 µS/cm) and the anode materials (An) were considered as variables to perform the Box-Behnken experimental design together with the response surface methodology analysis for optimization. The statistical analysis indicated that, in the evaluated range, the disinfection efficiency increased with an increase in j and decreased with an increase in s. The following optimal conditions for the elimination of total and fecal coliforms were found: j: 10 mA/cm2, s: 500 µS/cm and BDD/Ti used as anode material. The BDD/Ti electrode let to achieve complete coliform elimination after ca. 20 min of reaction while the GP one needed ca. 27 min. In water treated with both BDD/Ti and GP anode, after 7 days, any coliforms growth was observed. As a result of the oxidation process, the total organic carbon and nitrite concentration decreased while nitrate concentration increased. © IWA Publishing 2018.
The electrochemical elimination of coliforms from water using BBD/Ti or graphite anodes: A comparative study
(International Water Association Publishing, 2018-04-01) Gil Pavas, E.; Arbelaez, Paula Eliana; Medina, J.; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; Gil Pavas, E.; Arbelaez, Paula Eliana; Medina, J.; Dobrosz-Gómez, I.; Angel Gomez-Garcia, Miguel; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
The elimination of total and fecal coliforms, from raw surface water, was carried out by electrochemical oxidation using either boron doped diamond (BDD/Ti) or graphite (GP) anodes, in a chloride-free medium. The optimal values of the operation parameters, maximizing the coliform elimination percentage, were determined using statistical experimental design. The current density ( j: 2-20 mA/cm2), the conductivity (s: 500-900 µS/cm) and the anode materials (An) were considered as variables to perform the Box-Behnken experimental design together with the response surface methodology analysis for optimization. The statistical analysis indicated that, in the evaluated range, the disinfection efficiency increased with an increase in j and decreased with an increase in s. The following optimal conditions for the elimination of total and fecal coliforms were found: j: 10 mA/cm2, s: 500 µS/cm and BDD/Ti used as anode material. The BDD/Ti electrode let to achieve complete coliform elimination after ca. 20 min of reaction while the GP one needed ca. 27 min. In water treated with both BDD/Ti and GP anode, after 7 days, any coliforms growth was observed. As a result of the oxidation process, the total organic carbon and nitrite concentration decreased while nitrate concentration increased. © IWA Publishing 2018.
In vitro mechanical evaluation of mandibular bone transport devices
(ASME, 2014-06-01) Zapata, Uriel; Watanabe, Ikuya; Opperman, Lynne A.; Dechow, Paul C.; Mulone, Timothy; Elsalanty, Mohammed E.; Zapata, Uriel; Watanabe, Ikuya; Opperman, Lynne A.; Dechow, Paul C.; Mulone, Timothy; Elsalanty, Mohammed E.; Universidad EAFIT. Departamento de Ingeniería de Producción; Materiales de Ingeniería
Bone transport distraction osteogenesis (BTDO) is a surgical procedure that has been used over the last 30 years for the correction of segmental defects produced mainly by trauma and oncological resections. Application of BTDO has several clinical advantages over traditional surgical techniques. Over the past few years, several BTDO devices have been introduced to reconstruct mandibular bone defects. Based on the location and outline of the defect, each device requires a uniquely shaped reconstruction plate. To date, no biomechanical evaluations of mandibular BTDO devices have been reported in the literature. The present study evaluated the mechanical behavior of three different shaped prototypes of a novel mandibular bone transport reconstruction plate and its transport unit for the reconstruction of segmental bone defects of the mandible by using numerical models complemented with mechanical laboratory tests to characterize strength, fatigue, and stability. The strength test evaluated device failures under extreme loads and was complemented with optimization procedures to improve the biomechanical behavior of the devices. The responses of the prototypes were characterized to improve their design and identify weak and strong regions in order to avoid posterior device failure in clinical applications. Combinations of the numerical and mechanical laboratory results were used to compare and validate the models. In addition, the results remark the importance of reducing the number of animals used in experimental tests by increasing computational and in vitro trials. © VC 2014 by ASME.
In vitro mechanical evaluation of mandibular bone transport devices
(ASME, 2014-06-01) Zapata, Uriel; Watanabe, Ikuya; Opperman, Lynne A.; Dechow, Paul C.; Mulone, Timothy; Elsalanty, Mohammed E.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Bone transport distraction osteogenesis (BTDO) is a surgical procedure that has been used over the last 30 years for the correction of segmental defects produced mainly by trauma and oncological resections. Application of BTDO has several clinical advantages over traditional surgical techniques. Over the past few years, several BTDO devices have been introduced to reconstruct mandibular bone defects. Based on the location and outline of the defect, each device requires a uniquely shaped reconstruction plate. To date, no biomechanical evaluations of mandibular BTDO devices have been reported in the literature. The present study evaluated the mechanical behavior of three different shaped prototypes of a novel mandibular bone transport reconstruction plate and its transport unit for the reconstruction of segmental bone defects of the mandible by using numerical models complemented with mechanical laboratory tests to characterize strength, fatigue, and stability. The strength test evaluated device failures under extreme loads and was complemented with optimization procedures to improve the biomechanical behavior of the devices. The responses of the prototypes were characterized to improve their design and identify weak and strong regions in order to avoid posterior device failure in clinical applications. Combinations of the numerical and mechanical laboratory results were used to compare and validate the models. In addition, the results remark the importance of reducing the number of animals used in experimental tests by increasing computational and in vitro trials. © VC 2014 by ASME.
Optimization and toxicity assessment of a combined electrocoagulation, H2O2/Fe2+/UV and activated carbon adsorption for textile wastewater treatment
(Elsevier, 2019-02-15) GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; Universidad EAFIT. Departamento de Ingeniería de Procesos; Procesos Ambientales (GIPAB)
In this study, the potential application of sequential Electrocoagulation + Fenton (F) or Photo-Fenton (PF) + Active carbon adsorption (EC + F/PF + AC) processes were analyzed as alternatives for the treatment of an industrial textile wastewater resulting from an industrial facility located in Medellín (Colombia). In order to maximize the organic matter degradation, each step of the treatment was optimized using the Response Surface Methodology. At first, the optimal performance of EC was achieved with Fe electrodes operating at pH = 7, jEC = 10 mA/cm2 and 60 rpm, during 10 min of electrolysis. At these conditions, EC let to remove 94% of the dye's color, 56% of the COD and 54% of the TOC. Next, sequentially applied Fenton or photo-Fenton process (i.e., EC + F/PF), operating at the optimized conditions (pH = 4.3, [Fe2+] = 1.1 mM, [H2O2] = 9.7 mM, stirring velocity = 100 rpm and reaction time = 60 min.), improved the quality of the treated effluent. The EC + F let to achieve total color reduction, as well as COD and TOC removals of 72 and 75%, respectively. The EC + PF reached 100% of color, 76% of COD and 78% of TOC reductions. The EC + F/PF processes were more efficient than EC in elimination of low molecular weight (<5 kDa) compounds from wastewater. Moreover, the BOD5/COD ratio increased from 0.21 to 0.42 and from 0.21 to 0.46 using EC + F and EC + PF processes, respectively. However, EC + F/PF were not fully effective for the removal of acute toxicity to Artemia salina: 20% and 60% of reduction in toxicity using EC + F and EC + PF, respectively, comparing to very toxic (100%) raw textile wastewater. Thus, activated carbon adsorption was applied as an additional step to complete the treatment. After AC adsorption, the acute toxicity decreased to 10% and 0% using EC + F and EC + PF, respectively. The total operational costs, including chemical reagents, electrodes, energy consumption and sludge disposal, were of 1.65 USD/m3 and 2.3 USD/m3 for EC + F and EC + PF, respectively. © 2018 Elsevier B.V.
Optimization and toxicity assessment of a combined electrocoagulation, H2O2/Fe2+/UV and activated carbon adsorption for textile wastewater treatment
(Elsevier, 2019-02-15) GilPavas, E; Dobrosz-Gomez, I; Gomez-Garcia, MA; Universidad EAFIT. Departamento de Ingeniería de Procesos; Desarrollo y Diseño de Procesos
In this study, the potential application of sequential Electrocoagulation + Fenton (F) or Photo-Fenton (PF) + Active carbon adsorption (EC + F/PF + AC) processes were analyzed as alternatives for the treatment of an industrial textile wastewater resulting from an industrial facility located in Medellín (Colombia). In order to maximize the organic matter degradation, each step of the treatment was optimized using the Response Surface Methodology. At first, the optimal performance of EC was achieved with Fe electrodes operating at pH = 7, jEC = 10 mA/cm2 and 60 rpm, during 10 min of electrolysis. At these conditions, EC let to remove 94% of the dye's color, 56% of the COD and 54% of the TOC. Next, sequentially applied Fenton or photo-Fenton process (i.e., EC + F/PF), operating at the optimized conditions (pH = 4.3, [Fe2+] = 1.1 mM, [H2O2] = 9.7 mM, stirring velocity = 100 rpm and reaction time = 60 min.), improved the quality of the treated effluent. The EC + F let to achieve total color reduction, as well as COD and TOC removals of 72 and 75%, respectively. The EC + PF reached 100% of color, 76% of COD and 78% of TOC reductions. The EC + F/PF processes were more efficient than EC in elimination of low molecular weight (<5 kDa) compounds from wastewater. Moreover, the BOD5/COD ratio increased from 0.21 to 0.42 and from 0.21 to 0.46 using EC + F and EC + PF processes, respectively. However, EC + F/PF were not fully effective for the removal of acute toxicity to Artemia salina: 20% and 60% of reduction in toxicity using EC + F and EC + PF, respectively, comparing to very toxic (100%) raw textile wastewater. Thus, activated carbon adsorption was applied as an additional step to complete the treatment. After AC adsorption, the acute toxicity decreased to 10% and 0% using EC + F and EC + PF, respectively. The total operational costs, including chemical reagents, electrodes, energy consumption and sludge disposal, were of 1.65 USD/m3 and 2.3 USD/m3 for EC + F and EC + PF, respectively. © 2018 Elsevier B.V.

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