Universidad Católica de Santa Fe
  • Santa Fe de la Vera Cruz, Argentina
Recent publications
This current work has focused on the evaluation of the hexavalent chromium – Cr (VI) adsorption carried out by a biocomposite based on rice husk and chitosan. The chromium IV is an agro industrial contaminant residual while chitosan is a natural biopolymer with a great adsorption of heavy metals. Conditions for the biosorption such as concentrations of rice husk and Cr (VI) alongside the contact time, were identified in order to achieve the highest biosorpion of the heavy metal – Cr (VI). The morphology of rice husk, carried out in a Scanning Electron Microscopy (SEM), showed a porous surface which can allow the adherence of chitosan. Different concentrations of rice husk (10, 20, 30, 40, 50 ) were used for the synthesis of the biopolymer. Furthermore, the capacity of Cr (VI) adsorption of the biocomposite based on rice husk and chitosan was evaluated throughout the contact time, resulting in a 68.28 % of Cr (IV) removal at 120 minutes. Additionally, the results of the experimental design consistent with the adsorption kinetic designs are shown in this work.
Bioremediation technologies have demonstrated significant success on biological quality recovery of hydrocarbon contaminated soils, employing techniques among which composting and vermiremediation stand out. The aim of this study was to evaluate the efficiency of these processes to remediate diesel-contaminated soil, employing local organic materials and earthworms. During the initial composting stage (75 days), the substrate was made up using contaminated soil, lombricompost, rice hulls and wheat stubbles (60:20:15:5% w/w). Diesel concentration in the contaminated substrate was about 5 g kg⁻¹, equivalent to a Total Petroleum Hydrocarbon (TPH) experimental concentration of 3425 ± 50 mg kg⁻¹. During the later vermiremediation stage (60 days), the earthworm species Eisenia fetida and Amynthas morrisi were evaluated for their hydrocarbon degradation capacity. Physicochemical and biological assays were measured at different times of each stage and ecototoxicity assays were performed at the end of the experiments. TPH concentration reduced 10.91% after composting and from 45.2 to 60.81% in the different treatments after vermiremediation. Compared with TPH degradation in the treatment without earthworms (16.05%), results indicate that earthworms, along with indigenous microorganisms, accelerate the remediation process. Vermiremediation treatments did not present phytotoxicity and reflected high substrate maturity values (>80% Germination Index) although toxic effects were osberved due to E. fetida and A morrisi exposure to diesel. Vermiremediation was an efficient technology for the recovery of substrate biological quality after diesel contamination in a short period. The addition of organic materials and suitable food sources aided earthworm subsistence, promoted the decontamination process and improved the substrate quality for future productive applications.
Background Abnormal cellular lipid metabolism appears to underlie SARS-CoV-2 cytotoxicity and may involve inhibition of peroxisome proliferator activated receptor alpha (PPARα). Fenofibrate, a PPAR-α activator, modulates cellular lipid metabolism. Fenofibric acid has also been shown to affect the dimerization of angiotensin-converting enzyme 2, the cellular receptor for SARS-CoV-2. Fenofibrate and fenofibric acid have been shown to inhibit SARS-CoV-2 replication in cell culture systems in vitro . Methods We randomly assigned 701 participants with COVID-19 within 14 days of symptom onset to 145 mg of fenofibrate (nanocrystal formulation with dose adjustment for renal function or dose-equivalent preparations of micronized fenofibrate or fenofibric acid) vs. placebo for 10 days, in a double-blinded fashion. The primary endpoint was a ranked severity score in which participants were ranked across hierarchical tiers incorporating time to death, duration of mechanical ventilation, oxygenation parameters, subsequent hospitalizations and symptom severity and duration. ClinicalTrials.gov registration: NCT04517396. Findings: Mean age of participants was 49 ± 16 years, 330 (47%) were female, mean BMI was 28 ± 6 kg/m ² , and 102 (15%) had diabetes mellitus. A total of 41 deaths occurred. Compared with placebo, fenofibrate administration had no effect on the primary endpoint. The median (interquartile range [IQR]) rank in the placebo arm was 347 (172, 453) vs. 345 (175, 453) in the fenofibrate arm (P = 0.819). There was no difference in various secondary and exploratory endpoints, including all-cause death, across randomization arms. These results were highly consistent across pre-specified sensitivity and subgroup analyses. Conclusion Among patients with COVID-19, fenofibrate has no significant effect on various clinically relevant outcomes.
In this study, the degree of acetylation (DA) and degree of deacetylation (DDA) were determined by Fourier Transform Infrared Spectroscopy (FT-IR) analysis, and their viability was evaluated by the cytocompatibility test with L132 epithelial cells, from samples of chitin and chitosan extracted of Cryphiops caementarius. FT-IR measurements resulted in the successful determination of DA and DDA. Particularly the results showed that, the chitosan CHT-C has the highest DDA (93%), while viability tests employed to determine the cytotoxicity of chitin and chitosan showed that the cell survival rate of CH-C and CHT-C are 130% and 75% respectively while commercial CHT has a rate of 80% approximately, demonstrating that the CH-C (chitin) a favorable behavior against L132 cell.
The intensification of livestock farming has led to the expansion of feedlots in many countries and Argentina is not an exception. As in any other husbandry context, there is a need to objectively adopt an evidence-based approach to monitoring animal welfare in feedlots. This research aimed to describe the stages that took part in the development process of Bienest.AR, a beef cattle evaluation protocol adapted to the different conditions of the national feedlots, respecting validity, reliability, and feasibility criteria. The process to achieve this goal included the following seven stages: 1- Identification of welfare indicators considering animal- (ABM), resource- (RBM) and management-based measurements (MBM), by organising them according to the FAWC Five Freedoms, the Five Domains Model, and the welfare principles and criteria applied by Welfare Quality® and AWIN methods; 2- Validation of Gold Standards; 3- Evaluator’s training and first reliability testing by Spearman's Rank correlation coefficient; 4- Selection of indicators through focus groups; 5- Field application on 25 farms; 6- Feasibility and second reliability testing by Kendall Correlation Coefficient; and 7- Weighing of indicators and defining the classification method. Of the 150 candidate measurements initially obtained from the literature review, 57 were pre-selected and 28 were finally selected based on their validity, reliability and practicality to integrate the final protocol (18 ABM, 8 RBM and 2 MBM). In addition, the final protocol included information about: preliminary interview; sampling order; estimated evaluation time; sample size; equipment required; and steps to follow from arrival at the farm until completion of the evaluation. The protocol was applied in 25 feedlots and 54238 animals, and required a minimum time of 290 min to a maximum of 495 min to be completed. Statistically significant (p < 0.05) concordance among the observers was found for all the selected ABM analysed using Spearman's rank correlation coefficient. Given the simplicity for its evaluation, the reliability of RBM and MBM included in this protocol has not been evaluated. This research allowed the development of the first standard welfare assessment protocol for beef cattle feedlots in Argentina. Further applications of the described welfare assessment tool in many feedlots will reinforce the validation of the proposed measurements and allow the diagnosis of the global situation of animal welfare in feedlots in Argentina and other countries applying comparable fattening systems.
Background The relationship between the Body Mass Index (BMI) with physical fitness in children and adolescent populations from diverse regions are consistent. However, the relationship between the Ponderal Index (PI) with physical fitness, based on what is known to date, has not been examined in depth. The objective was to evaluate the relationships between BMI and PI with three physical fitness tests of students living at moderate altitudes in Peru. Methods A descriptive correlational study was carried out with 385 adolescents, between the ages of 10.0 to 15.9 years old, from the province of Arequipa, Peru. Weight, height, and three physical fitness tests (horizontal jump, agility, and abdominal muscle resistance) were evaluated. BMI and PI were calculated, and they were, then, categorized into three strata (low, normal, and excessive weight). Specific regressions were calculated for sex, using a non-lineal quadratic model for each item adjusted for BMI and PI. Results The relationship between BMI and PI with the physical tests reflected parabolic curves that varied in both sexes. The regression values for BMI in males oscillated between R² = 0.029 and 0.073 and for females between R² = 0.008 and 0.091. For PI, for males, it varied from R² = 0.044 to 0.82 and for females, from R² = 0.011 to 0.103. No differences occurred between the three nutritional categories for BMI as well as for PI for both sexes (p range between 0.18 to 0.38), as well as for low weight (BMI vs PI), normal weight (BMI vs PI), and excessive weight (BMI vs PI) (p range between 0.35 to 0.64). Conclusions BMI showed inferior quadratic regressions with respect to the PI. In addition, physical performance was slightly unfavorable when it was analyzed by BMI. PI could be a useful tool for analyzing and predicting physical fitness for adolescents living at a moderate altitude since it corrects for the notable differences for weight between adolescents.
La presente investigación tiene como finalidad realizar el estudio del estado en que se encuentra el clima organizacional en un institución adscrita al Ministerio de Justicia en el departamento de Arequipa – Perú, capacitar al personal en temas relacionados con la mejora del clima organizacional y evaluar a los trabajadores luego de las capacitaciones impartidas, para lo cual se tomará un grupo control y un grupo experimental, los que serán pareados en cuanto a edad, sexo, grupo ocupacional, tiempo de servicios y condición laboral. Se desarrolló un programa de capacitación adecuado para el tipo de Institución, teniendo en cuenta que la actividad principal es la de servicio público, las cuales se han realizado en cinco sesiones de cuatro horas, con un método didáctico basado en actividades de grupo y juegos, teniendo la participación activa de los participantes. Se aplicó como instrumento la prueba de Sonia Palma Carrillo, la misma que se aplicó tanto en el pretest como en el postest, obteniendo los resultados diferentes en el grupo experimental, los cuales han sido medidos estadísticamente con diferentes pruebas de acuerdo al tipo de comparación realizado en cada uno de ellos.
Background: The COVID-19 pandemic has significantly influenced the routine of healthcare workers. This study investigated the impact of the pandemic on dental practice and dentists' feelings in Latin America. Methods: A survey was conducted with dentists from 11 Spanish-speaking Latin American countries in September-December 2020. Professionals were invited by email and via an open campaign promoted on social media. The questions investigated dental care routines, practice changes, and feelings about the pandemic. Descriptive statistics were used to identify frequencies and distributions of variables. Proportions were compared using chi-square tests. Results: A total of 2127 responses were collected from a sample with diverse demographic, sex, work, and education characteristics. The impact of COVID-19 was considered high/very high by 60% of respondents. The volume of patients assisted weekly was lower compared with the pre-pandemic period (mean reduction = 14 ± 15 patients). A high rate of fear to contracting the COVID-19 at work was observed (85%); 4.9% of participants had a positive COVID-19 test. The main professional challenges faced by respondents were reduction in the number of patients or financial gain (35%), fear of contracting COVID-19 (34%), and burden with or difficulty in purchasing new personal protective equipment (22%). The fear to contracting COVID-19 was influenced by the number of weekly appointments. A positive test by the dentists was associated with their reports of having assisted COVID-19 patients. The most cited feelings about the pandemic were uncertainty, fear, worry, anxiety, and stress. Negative feelings were more prevalent for professionals who did not receive training for COVID-19 preventive measures and those reporting higher levels of fear to contract the disease. Conclusion: This multi-country survey indicated a high impact of the pandemic on dental care routines in Latin America. A massive prevalence of bad feelings was associated with the pandemic.
Emanuel Lévinas ha desarrollado su ética de la alteridad a partir de una visión de la subjetividad como lenguaje y proximidad. Este artículo indaga en la noción de verdad como inspiración propuesta por Lévinas, la cual se presenta como una alternativa a la concepción clásica de verdad como desvelamiento y representación. Metodológicamente se analiza la obra levinasiana, en especial De otro modo que ser o más allá de la esencia, llegando a la conclusión de que la subjetividad inspirada y profética, lo otro en el mismo que interpela a la responsabilidad, abre el horizonte de una verdad que no es adecuación sino enseñanza e inquietud. La verdad no emerge como una actividad cognoscitiva del sujeto individual, sino que nace en la praxis ética como inspiración a la responsabilidad.
Composites are a group of materials that for several years have been attracting the attention of the international scientific community, these materials combine the properties of two or more types of materials to make a new one with better properties than those of their precursors, without them react chemically. This paper presents a study about the manufacture of new composite materials of wood sawdust dust, obtained by hot pressing at 180 ° C and reinforced with natural fibers from Peru (alpaca wool and ichu). The mean apparent density found for all the compounds was around 1.21 g/cm3 and the values of maximum stress and modulus of elasticity reported were in the range of 77 - 95 MPa and 3.5 - 4.1 GPa, respectively. The microstructures found for all the compounds consist of a continuous and homogeneous matrix of lignin (from wood) with short fibers of alpaca and ichu wool, dispersed in the continuous matrix.
The present work studies the mechanical behavior of rice husk as a reinforcement element in mixtures of polyolefins. The composites were made by polyolefin mixtures of 30% LDPE, 40% HDPE and 30% PP, rice husk and Polybond as a compatibilizer. Samples for the tensile test were prepared by injection and compressive methods. The results confirm that rice husk alongside the compatibilizer bring about positively in the strength of composites. In reference to the adherence of rice husk to the mixture of polyolefins, which was studied from the microstructure of composites, the addition of compatibilizer improves the adherence between the polyolefins and rice husk, and thereby the quality in the fracture surface. These composites are considered to be a good alternative for the recovery of plastic agricultural waste.
This article is oriented to the analysis of the reflective itinerary made by Hannah Arendt in the first part of The Life of the Mind, dedicated to thinking. It stops, above all, on the distinction between truth and meaning that is made in this part, with a view in order to highlighting the inherent responsibility of human beings in relation to the understanding of the ultimate meaning of their existence and of the totality of reality. The text is organized in three sections. In the first one, Arendt’s ideas about the tensions and demands presented by the «departures and returns» that constitute the activity of thought in relation to appearances are examined. In the second one, the reflection focuses on the resignification operated by Arendt to the Kantian distinction between the faculties of «intellect», on the one hand and which corresponds to know the truth, and «reason», on the other hand, whose mental activity is thinking and understanding the meaning. The last section exposes the reasons for the centrality given by Arendt to the task of understanding the meaning that each human being and each generation must update by themselves and in an always new way.
p>En el presente trabajo proponemos abordar y problematizar algunos aspectos de la “opción decolonial” propuesta por Walter Mignolo. Específicamente nos interesa indagar cómo la articulación de dos categorías centrales de su pensamiento, “diferencia colonial” y “geopolítica del conocimiento”, da lugar a una política decolonial con una fuerte impronta identitaria que busca des-prenderse de todo legado moderno. Para profundizar esta problematización, y como principal aporte del escrito, proponemos retomar la noción de “reparto de lo sensible” (partage du sensible) del filósofo argelino-francés Jacques Rancière para ver si es posible y qué implicancias tendría pensar la colonialidad desde esta perspectiva. Trazar este vínculo conceptual nos permitirá elucidar por qué el dispositivo teórico de Mignolo, al estabilizar una relación entre modo de ser, lugar y pensamiento, reproduce cierta lógica colonial y también puede abrirnos a una compresión de la decolonialidad que no descanse en un sesgo identitario. Para explorar este último punto pondremos en diálogo el modo en que Rancière piensa los procesos de subjetivación política con una práctica decolonial específica: la apropiación de los símbolos y discursos de la Revolución Francesa que llevaron a cabo los esclavos negros en la gesta revolucionaria haitiana.</p
Background Adding wearable resistance (WR) to training results in superior performance compared with unloaded conditions. However, it is unclear if adding WR during warm-up influences training load (TL) in the subsequent session. The aim of this research was to track TL in soccer players during the transition from late preseason to early in-season and examine whether adding WR to the lower leg during a warm-up influenced TL measures during warm-ups and on-field training sessions after WR was removed. Hypothesis The addition of WR worn on the lower legs during an on-field warm-up would lead to decreases in relatively high-intensity external TL metrics, such as distance covered >6.11 m∙s ⁻¹ and acceleration and deceleration >/<3 m∙s ⁻² and increases in internal TL during the warm-up, yet would have little effect on the subsequent training session when WR was removed. Study Design Matched-pair randomized design. Level of Evidence Level 3. Methods A total of 28 soccer players were allocated to either a WR training (WRT = 14) or unloaded (control [CON] = 14) group. Both groups performed the same warm-up and on-field training for 8 weeks, with the WRT group wearing 200 g to 600 g loads on their lower leg during the warm-up. External TL was measured via global positioning system data and internal TL was assessed using session rating of perceived exertion (sRPE × time per session). Results No statistically significant between-group differences ( P ≥ 0.05) were identified for any TL measurement during either warm-ups or training sessions. Lower leg WR resulted in trivial to moderate effects for all external TL metrics (−16.9% to 2.40%; d = −0.61 to 0.14) and sRPE (−0.33%; d = −0.03) during the warm-up and trivial to small effects on all external TL metrics (−8.95% to −0.36%; d = −0.45 to −0.30) and sRPE (3.39%; d = 0.33) during training sessions. Conclusion Warming up with lower leg WR negatively affects neither the quality and quantity of the warm-up nor the subsequent training session once WR is removed. Clinical Relevance Using WR on the lower leg during on-field warm-ups may be a means to “microdose” strength training while not unduly increasing TL. However, further research is needed to determine the influence of WR on strength qualities.
We present a data‐driven approach to clustering or grouping Global Navigation Satellite System (GNSS) stations according to observed velocities, displacements or other selected characteristics. Clustering GNSS stations provides useful scientific information, and is a necessary initial step in other analysis, such as detecting aseismic transient signals (Granat et al., 2013, https://doi.org/10.1785/0220130039). Desired features of the data can be selected for clustering, including some subset of displacement or velocity components, uncertainty estimates, station location, and other relevant information. Based on those selections, the clustering procedure autonomously groups the GNSS stations according to a selected clustering method. We have implemented this approach as a Python application, allowing us to draw upon the full range of open source clustering methods available in Python's scikit‐learn package (Pedregosa et al., 2011, https://doi.org/10.5555/1953048.2078195). The application returns the stations labeled by group as a table and color coded KML file and is designed to work with the GNSS information available from GeoGateway (Donnellan et al., 2021, https://doi.org/10.1007/s12145-020-00561-7; Heflin et al., 2020, https://doi.org/10.1029/2019ea000644) but is easily extensible. We demonstrate the methodology on California and western Nevada. The results show partitions that follow faults or geologic boundaries, including for recent large earthquakes and post‐seismic motion. The San Andreas fault system is most prominent, reflecting Pacific‐North American plate boundary motion. Deformation reflected as class boundaries is distributed north and south of the central California creeping section. For most models a cluster boundary connects the southernmost San Andreas fault with the Eastern California Shear Zone (ECSZ) rather than continuing through the San Gorgonio Pass.
This paper studies the influence of metal precursors in the CVD´s catalyst synthesis of carbon nanotubes (CNTs) used as fillers in a polypropylene (PP) matrix (∼0.3 wt%). Two catalytic schemes, Fe/Al 2 O 3 (50:50) and Ni–Fe/Al 2 O 3 (40:10:50), were prepared to determine the influence of the reduction temperature over the characteristics and mechanical properties of CNT as PP fillers. The conversion temperature was varied to see the dependance of the CNT structure to this variable (700 °C–750 °C–800 °C). CNTs products were characterized by SEM and Raman spectroscopy. The SEM micrographs showed a sharper fiber type CNTs for the bimetallic catalyst and the Raman confirmed that better crystallites are obtain over the Fe catalyst. The Fe–PP composite presented enhanced mechanical properties when compare with Fe–Ni–PP, with tensile strength, hardness, and impact properties are higher in 16%, 9%, and 9% respectively. Other carbonaceous materials, as CNF, with less crystallinity presented poorer mechanical properties. Finally, can be stated that for the use of CNF as fillers in PP composites a Fe/Al 2 O 3 catalyst, and a reaction temperature 700 °C–750 °C will produce a CNF with 60 nm mean diameter, is better than the use of Fe-Ni based catalysts.
Objetivo: Identificar sistemáticamente la evidencia científica publicada en revistas indexadas en los últimos años sobre la violencia doméstica y analizar aspectos relevantes para contrastar con la legislación peruana. Método: Se realizó la búsqueda y revisión manual de publicación científica en 7 bases de datos. El número total de artículos obtenidos a partir de las búsquedas ha sido de seiscientos veinte mil seiscientos veintiocho (620 628) de los cuales, después de aplicar los criterios de inclusión y exclusión se seleccionaron dieciocho (18). Resultados: Del análisis y discusión de cada uno de los artículos se evidenció la relevancia actual que comprende la estadística de la violencia doméstica, resultando en afectar emocionalmente para el desarrollo de la integridad de la víctima; las repercusiones posteriores demuestran una necesidad de enfrentar la problemática desde distintos ámbitos, aparte del legal, que si bien es demostrada su ineficacia para combatir el ya mencionado problema en la jurisdicción peruana, se pueden evaluar distintas otras variables que resultan en una acepción más amplia del tema, que, objetivamente proveerá de mejores soluciones.
Introducción: los trastornos temporomandibulares son unas condiciones dolorosas o disfuncionales en los músculos masticadores o en la articulación temporomandibular con síntomas y signos complejos y variados que influyen negativamente en la calidad de vida. La evidencia científica es ambigua al querer relacionar la postura corporal con la presencia o ausencia de esta alteración. El objetivo es determinar la relación entre la postura de las cinturas escapular y pelviana y la convergencia ocular con los trastornos temporomandibulares. Materiales y métodos: se realizó una investigación observacional, correlacional, prospectiva, transversal. La población estaba constituida por 146 pacientes de 18 a 47 años que acudieron al servicio de odontología del Hospital Honorio Delgado Espinoza y que cumplieron con los criterios de elegibilidad. Se empleó el índice de Helkimo modificado por Maglione para la evaluación de los trastornos temporomandibulares, y para la postura de las cinturas escapular y pelviana y la convergencia ocular se empleó el protocolo de evaluación clínica del Dr. Dupas de la Universidad de Lille (Francia). Resultados: 91.1 % presentaron trastornos temporomandibulares; 86.3 %, disfunción leve; 4.8 %, disfunción moderada, con un predominio femenino, en un 67.8 %. Las manifestaciones clínicas resultantes fueron desviación mandibular, ruidos articulares y limitación de movimiento mandibular moderado. La relación entre la no alineación de las cinturas escapular y pelviana con los trastornos temporomandibulares fue altamente significativa y no se encontró relación con la convergencia ocular. Conclusiones: se evidenció una relación estadística altamente significativa entre los trastornos temporomandibulares y la postura alterada de las cinturas señaladas. No se encontró relación con la hipoconvergencia ocular.
There is ongoing debate as to whether fish body size will decrease with global warming and how these changes may impact dispersal ability and speciation rate. Theory predicts that, under warmer temperatures, fish grow to a smaller size, undergo a reduction in dispersal ability and increase speciation rates. However, evaluations of such predictions are hampered owing to the lack of empirical data spanning both wide temporal and geographical scales. Here, using phylogenetic methods, we show that smaller clupeiform fish (anchovies and herrings) occurred historically in warmer waters, moved the shortest distances at low speed and displayed the lowest speciation rates. Furthermore, fish moved faster and evolved rapidly under higher rates of temperature change but these historical rates are far lower than current warming rates. Our results predict a future where smaller clupeiform fish that have reduced ability to move will be more prevalent; this, in turn, may reduce future speciation. Phylogenetic data over the past ~150 million years show smaller fish occurred in warmer waters, moved shorter distances at low speed and had low speciation rates. Fish moved faster and evolved quicker under periods of rapid change, with implications for movement and survival under climate change.
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114 members
Ana María Bonet
  • Facultad de Derecho
María Celeste Nessier
  • Facultad de Ciencias de la Salud
Esteban Piva
  • Facultad de Derecho
Elisabet Vidal
  • Facultad de Derecho
Manuela Vázquez
  • Facultad de Humanidades
Santa Fe de la Vera Cruz, Argentina