Resumen Con el aumento de la masa de las máquinas y el tránsito repetido se han ido incrementando los problemas de compactación. Además, frecuentemente se transitan los lotes en condiciones de baja capacidad portante generando una compactación superficial del suelo importante (huelleado). Se realizó un ensayo para determinar la influencia del número de pasadas y de la humedad del suelo en el momento del tránsito sobre la compactación del suelo. Se realizaron 1, 3 y 10 pasadas de un tractor con el suelo a dos contenidos de humedad (34 % = húmedo y 24 % = parcialmente seco (PS)). Se midieron la profundidad de huella, la humedad gravimétrica, la resistencia a la penetración y la producción de materia seca del pastizal natural como variables respuesta en dos instancias: inicial (24 h después de una precipitación) y final (luego de las PS). Adicionalmente, en la instancia final se determinó la conductividad hidráulica a distintas tensiones, distribución de tamaño de poros y densidad aparente (DAP). El mayor huelleado se produjo con el tránsito en húmedo y con el incremento del número de pasadas. En los tratamientos con tránsito se alcanzaron valores de resistencia a la penetración que limitan o detienen el crecimiento radical y en consecuencia comprometen el rendimiento del cultivo. Se observó un aumento de la DAP y una disminución de la macroporosidad ante el tránsito repetido especialmente en condiciones secas (P<0,05). El tratamiento de mayor número de pasadas en PS fue el que tuvo menor rendimiento de materia seca.

Abstract With the increase in machinery mass and repeated traffic, compaction problems have arised. In addition, plots are frequently trafficked in conditions of low bearing capacity, generating a significant compaction of the superficial soil (tracks). A trial was carried out to determine the influence of the number of passes and soil moisture during transit on soil compaction. Tractor passes (1, 3 and 10) were done with the soil at two moisture contents (34% = wet and 24% = partially dry). Track depth, gravimetric moisture content, penetration resistance, and dry matter production were measured on a natural grassland at two moments: initial (24 h after a rainfall event) and final (when the soil PS). Additionally, hydraulic conductivity at different water pressure heads, pore size distribution and bulk density (DAP) were determined at the final measure. The greatest track depth occurred with wet traffic and with the increase in the number of passes. In the treatments with traffic, values of penetration resistance that limit or stop root growth and consequently compromise crop yield were reached. The treatment with the highest number of partially dry passes had the lowest dry matter yield. An increase in DAP and a decrease in macroporosity were observed as a result of repeated traffic, especially in dry conditions (P<0.05). The treatment with the highest number of passes in PS was the one with the lowest yield of dry matter.

Resumen Introducción: el Síndrome de Imerslund-Gränsbeck es un trastorno congénito inusual que cursa con disminución de la Vitamina B12, anemia megaloblástica y proteinuria sin afección renal que cual se produce por una mutación de los cromosomas 10 y 14, que condicionan un defecto en el receptor del complejo vitamina B12-factor intrínseco del enterocito ileal. Fue descrita por Olga Imerslund y Armas Gransbeck. Objetivo: caracterizar a la población que ha padecido el Síndrome de Imerslund-Gränsbeck. Metodología: revisión sistemática de la literatura de casos clínicos. Resultados: se incluyeron 68 casos, en la mayoría de los casos el diagnostico en los primeros 10 años de vida, en el que se evidenció una mayor frecuencia en mujeres, y se encontró asociado con antecedentes familiares como consanguinidad entre padres (14,6%). La manifestación más frecuente fue palidez (20,9%), seguido de vomito (10,5%) y anorexia (9,8%). La anemia megaloblástica (66,2%) fue el hallazgo más frecuente y el tratamiento se dio con cianocobalamina (intramuscular u oral) para regular las concentraciones plasmáticas de esta vitamina. Conclusión: el Síndrome de Imerslund Gränsbeck tiene una baja prevalencia y se presenta con mayor frecuencia en el continente europeo, tiene predilección por el sexo femenino y se caracteriza por una disminución de la vitamina B12 que pueden que puede predisponer a otras alteraciones como ataxia y retraso en el crecimiento.

Abstract Introduction: Imerslund-Gränsbeck Syndrome is an unusual congenital disorder that causes a decrease in vitamin B12, megaloblastic anemia and proteinuria without kidney involvement that is caused by a mutation of chromosomes 10 and 14, which determine a defect in the complex receptor vitamin B12-ileal enterocyte intrinsic factor. It was described by Olga Imerslund and Armas Gransbeck. Objective: to characterize the population that has suffered from Imerslund Gränsbeck syndrome. Methodology: systematic review of the clinical case literature. Results: 68 cases were included, in most cases the diagnosis in the first 10 years of life, in which a higher frequency was found in women, and was found to be associated with family history such as consanguinity between parents (14.6%). The most frequent manifestation was paleness (20.9%), followed by vomiting (10.5%) and anorexia (9.8%). Megaloblastic anemia (66.2%) was the most frequent finding and treatment was given with cyanocobalamin (intramuscular or oral) to regulate plasma concentrations of this vitamin. Conclusion: Imerslund-Gränsbeck Syndrome has a low prevalence and occurs more frequently in the European continent, has a predilection for females and is characterized by a decrease in vitamin B12 that may predispose to other disorders such as ataxia and retardation in growth.

Resumen Introducción. La resección quirúrgica es el tratamiento de elección de las neoplasias primarias y secundarias del hígado. Los pacientes con hepatocarcinoma de los segmentos centrales representan un reto, siendo la hepatectomía extendida la técnica más usada, sin embargo, el riesgo postquirúrgico de falla hepática es alto, dado que la resección puede comprometer entre el 65 % y el 80 % del volumen hepático. La mesohepatectomía es una alternativa que permite dejar un volumen hepático residual suficiente. El objetivo de este trabajo es presentar nuestra experiencia en el tratamiento de pacientes con hepatocarcinomas en segmentos centrales a quienes se les realizó mesohepatectomía. Serie de casos. Se presentan tres pacientes no cirróticos, con hepatocarcinoma en los segmentos 4, 5 y 8, que fueron atendidos en el Hospital San Vicente Fundación, en las sedes de Medellín y de Rionegro, entre 2018 y 2020. Resultados. La mesohepatectomía se realizó mediante ligadura selectiva de los pedículos del segmento 4 y del sector anterior derecho. Se utilizó aspirador ultrasónico y endograpadora para la transección hepática. La duración de la maniobra de Pringle varió entre 16 y 43 minutos. El sangrado promedio fue de 1000 ml. Solo un paciente presentó fuga biliar tipo B. No hubo mortalidad a 30 días. Conclusiones. La mesohepatectomía es una alternativa segura para pacientes con tumores en los segmentos centrales, que permite disminuir el riesgo de falla hepática luego de la resección.

Abstract Introduction. Surgical resection is the treatment of choice for primary and secondary neoplasms of the liver. Patients with central segment hepatocarcinoma represent a challenge, with extended hepatectomy being the most widely used technique. However, the postsurgical risk of liver failure is high since resection can compromise between 65% and 80% of liver volume. Mesohepatectomy is an alternative that allows a sufficient residual liver volume to be left. The objective of this work is to present treatment of patients with central segment hepatocarcinoma. Clinical cases. Three non-cirrhotic patients are presented, with hepatocarcinoma in segments 4, 5 and 8, who were treated at the San Vicente Fundación Hospital in Medellín and Rionegro, between 2018 and 2020. Results. Mesohepatectomy was performed by selective ligation of the pedicles of segment 4 and the right anterior sector. An ultrasonic aspirator and endostapler were used for liver transection. The duration of the Pringle maneuver ranged from 16 to 43 minutes. The average bleeding was 1000 cc. Only one patient had type B bile leakage. There was no 30-day mortality. Conclusions. Mesohepatectomy is a safe alternative for patients with tumors in the central segments, which reduces the risk of liver failure after resection.

ABSTRACT BACKGROUND: The intensity of the thromboprophylaxis needed as a potential factor for preventing inpatient mortality due to coronavirus disease-19 (COVID-19) remains unclear. OBJECTIVE: To explore the association between anticoagulation intensity and COVID-19 survival. DESIGN AND SETTING: Retrospective observational study in a tertiary-level hospital in Spain. METHODS: Low-molecular-weight heparin (LMWH) status was ascertained based on prescription at admission. To control for immortal time bias, anticoagulant use was analyzed as a time-dependent variable. RESULTS: 690 patients were included (median age, 72 years). LMWH was administered to 615 patients, starting from hospital admission (89.1%). 410 (66.7%) received prophylactic-dose LMWH; 120 (19.5%), therapeutic-dose LMWH; and another 85 (13.8%) who presented respiratory failure, high D-dimer levels (> 3 mg/l) and non-worsening of inflammation markers received prophylaxis of intermediate-dose LMWH. The overall inpatient-mortality rate was 38.5%. The anticoagulant nonuser group presented higher mortality risk than each of the following groups: any LMWH users (HR 2.1; 95% CI: 1.40-3.15); the prophylactic-dose heparin group (HR 2.39; 95% CI, 1.57-3.64); and the users of heparin dose according to biomarkers (HR 6.52; 95% CI, 2.95-14.41). 3.4% of the patients experienced major hemorrhage. 2.8% of the patients developed an episode of thromboembolism. CONCLUSIONS: This observational study showed that LMWH administered at the time of admission was associated with lower mortality among unselected adult COVID-19 inpatients. The magnitude of the benefit may have been greatest for the intermediate-dose subgroup. Randomized controlled trials to assess the benefit of heparin within different therapeutic regimes for COVID-19 patients are required.

Abstract The balanced cast-in-place cantilever erection method has become a popular construction bridge technique. The main advantages include an industrialized erection technique that prevents the use of intermediate supports and rapid construction. However, the long-term response of this bridge typology is not well understood as long-term deflections due to time-dependent phenomena (such as creep and shrinkage) are significantly simplified in bridge design codes. Existing prediction models commonly used in design tend to underestimate long-term deflections, and as a result, field measurements conducted in newly constructed bridges still report excessive long-term deflections. This paper shows the long-term deflection analysis of a long-span concrete bridge located in Colombia and opened to traffic in 2014. This study is conducted using field data collected within a one-year time interval and modelling results. Further comparisons using field data collected from bridges with similar structural configurations, but opened to traffic in the 90s and 2000s, show that the bridge's current situation is categorized as a major concern.

ABSTRACT Introduction: COVID-19 has been a multi-dimensional challenge for humanity, even more so for decision-makers responsible for acting in an accurate and timely manner to confront it. In Peru, with is a current favorable trend of the Pandemic, the spread of the Delta variant is imminent, hence the need for predictive information that makes it possible to make early decisions to mitigate its effects. Objective: To simulate scenarios applying the physical-mathematical modeling to predict the behavior of COVID-19 in Peru and facilitate decision-making. Material and Methods: Physical-mathematical modeling using MATLAB software tools and functions. Results: Determination of the behavior of the main variables associated with COVID-19 in Peru; physical-mathematical modeling based on the classic SIR with new compartments related to vaccination and those exposed, as well as its adjustment to the data from Peru; simulation of scenarios including the Delta variant for deceased persons, cumulative number of infected individuals, and infection in vaccinated and unvaccinated individuals. Conclusions: The model conceived for the simulation of COVID-19 evolution scenarios demonstrated its ability to predict the behavior of the most important variables that determine such evolution in Peru; another wave of infections may occur and cumulative figures between 2.9 and 3.36 million infected individuals and between 215 and 255 thousand deaths may be reached. The main mitigation strategies should be aimed at guaranteeing social distancing and isolation, as well as increasing the vaccination regimen.

RESUMEN Introducción: La COVID-19 ha constituido un reto de múltiples dimensiones para la humanidad, aún más para los decisores responsables de accionar de manera certera y oportuna para su enfrentamiento. En Perú, con una tendencia actual favorable de la Pandemia, es inminente la propagación de la variante Delta, de allí que requieran de informaciones predictivas que posibiliten adoptar decisiones anticipadas para mitigar sus efectos. Objetivo: Simular escenarios aplicando la modelación físico-matemática, para la predicción del comportamiento de la COVID-19 en Perú que facilite la adopción de decisiones. Material y Métodos: Modelación físico-matemática mediante herramientas y funciones del software MATLAB. Resultados: Determinación del comportamiento de las principales variables de la COVID-19 en Perú; modelo físico-matemático basado en el clásico SIR con nuevos compartimientos relacionados con la vacunación y los expuestos, así como su ajuste a los datos de Perú; simulación de escenarios, incluyendo la variante Delta, para fallecidos, infectados acumulados, infectados no vacunados e infectados vacunados. Conclusiones: El modelo concebido para la simulación de escenarios de evolución de la COVID-19, demostró su capacidad de predicción del comportamiento de las variables más importantes que determinan dicha evolución en Perú; debe ocurrir otra ola de contagios y llegarse a cifras acumulativas entre 2,9 y 3,36 millones de infectados y entre 215 y 255 mil fallecidos; las principales estrategias de mitigación deben dirigirse a garantizar el distanciamiento y aislamiento social, así como a incrementar el régimen de vacunación.

RESUMEN La inclusión de cultivos de cobertura (CC) puede mejorar el impacto de la siembra directa (NT), derivando en una mayor calidad física del suelo (SPQ). Los objetivos de este trabajo fueron: i- determinar la SPQ en diferentes momentos del ciclo de cultivo durante el primer año después de la introducción de un cultivo de cobertura (CC) de centeno y vicia, en comparación con barbecho desnudo (BF); y ii- medir el impacto de este cultivo de cobertura en el contenido de agua del suelo durante el primer año luego de su introducción, en comparación con BF. Se determinaron indicadores de la SPQ, derivados de la curva de retención hídrica (SWRC) y de ensayos de infiltración in-situ en diferentes momentos durante el primer año luego de la inclusión de un CC. El experimento fue realizado en un Argiudol abrúptico, fino, illítico, térmico. En ambos tratamientos el cultivo de verano fue maíz. El tratamiento CC, en comparación con el tratamiento BF, mostró mayores valores de, agua disponible (PAWC) e índice de Dexter (S), y menores valores de densidad aparente (BD). Se observó una mayor capacidad de campo (FC) bajo CC durante el ciclo de crecimiento del maíz. Por otro lado, no se observaron diferencias entre tratamientos para Pmac, exhibiendo las mismas tendencias temporales. Los resultados muestran que la inclusión de un CC mejora la capacidad de retener agua y contrarrestar procesos de compactación. Al final del ciclo de cultivo, CC mostró mayores valores de macroporosidad conductora de agua (εma) y conectividad de la macroporosidad (Cwma). Se observaron mayores valores de humedad durante el ciclo de cultivo del maíz en el tratamiento CC, mostrando que la inclusión de un CC no tiene un efecto negativo sobre el contenido de agua en el horizonte superficial. Nuestros resultados muestran que la inclusión de CC son una oportunidad de intensificar las secuencias de cultivos en la Región Pampeana Argentina, orientado a mejorar el impacto del sistema de NT.

ABSTRACT Integrating cover crops (CC) in the crop sequence could lead to an enhancement of the no-tillage (NT) performance improving soil physical quality (SPQ). The objectives of this work were: i- to determine the SPQ on different moments of the crop cycle during the first year after incorporation of cover cropping (barley and vetch) (CC), as compared with bare fallow (BF); and ii- to measure the impact of cover crops on the top soil water content during the first year of its introduction. SPQ indicators were determined from the soil water retention curve (SWRC) and in-situ infiltration data in different dates during the first year after inclusion of CC. The experiment was carried out in a fine, illitic, thermic abruptic Argiudoll. For both treatments, maize was sown as summer crop. CC management showed higher values of plant available water content (PAWC) and Dexter index (S), and lower values of bulk density (BD) as compared with BF. Higher values of field capacity (FC) under CC were observed during the maize growing season. On the other hand, no differences between treatments were observed for Pmac. These results show that the inclusion of CC under NT management improves the soil capacity to retain water and counteract compaction processes under NT. At the end of the crop cycle, higher values of water-conducting macroporosity (εma) and macropore connectivity (Cwma) were observed under CC. Higher values of soil water content during the maize growing period were observed under CC, showing that the inclusion of CC has no negative effects on the top soil water content. Our results show that the inclusion of CC is an opportunity for intensify crop sequences in the Argentinean Pampas Region, oriented to enhance the performance of NT.

COVID-19 has been a multi-dimensional challenge for humanity, even more so for decision-makers responsible for acting in an accurate and timely manner to confront it. In Peru, with a current favorable trend of the Pandemic, the spread of the Delta variant is imminent, hence they require predictive information that makes it possible to make early decisions to mitigate its effects. Consequently, the objective was established to simulate scenarios applying physical-mathematical modeling, which predict the behavior of COVID-19 in Peru and facilitate decision-making. As methods and techniques were applied: analysis-synthesis, documentary review and physical-mathematical modeling using tools and functions of the MATLAB software. The following are recognized as results: determination of the behavior of the main variables of COVID-19 in Peru; physical-mathematical model based on the classic SIR with new compartments related to vaccination and those exposed, as well as its adjustment to the data from Peru; simulation of scenarios, including the Delta variant, for deceased, accumulated infected, unvaccinated infected and vaccinated infected. It was concluded that: The model conceived for the simulation of COVID-19 evolution scenarios, demonstrated its ability to predict the behavior of the most important variables that determine said evolution in Peru; another wave of infections must occur and cumulative figures between 2.9 and 3.36 million infected and between 215 and 255 thousand deaths must be reached; The main mitigation strategies should be aimed at guaranteeing social distancing and isolation, as well as increasing the vaccination regimen.

La COVID-19 ha constituido un reto de múltiples dimensiones para la humanidad, aún más para los decisores responsables de accionar de manera certera y oportuna para su enfrentamiento. En Perú, con una tendencia actual favorable de la Pandemia, es inminente la propagación de la variante Delta, de allí que requieran de informaciones predictivas que posibiliten tomar decisiones anticipadas para mitigar sus efectos. Consecuentemente se estableció como objetivo simular escenarios aplicando la modelación físico-matemática, que predigan el comportamiento de la COVID-19 en Perú y faciliten la toma de decisiones. Como métodos y técnicas se aplicaron: análisis-síntesis, revisión documental y modelación físico-matemática mediante herramientas y funciones del software MATLAB. Se reconocen como resultados: determinación del comportamiento de las principales variables de la COVID-19 en Perú; modelo físico-matemático basado en el clásico SIR con nuevos compartimientos relacionados con la vacunación y los expuestos, así como su ajuste a los datos de Perú; simulación de escenarios, incluyendo la variante Delta, para fallecidos, infectados acumulados, infectados no vacunados e infectados vacunados. Se concluyó que: El modelo concebido para la simulación de escenarios de evolución de la COVID-19, demostró su capacidad de predicción del comportamiento de las variables más importantes que determinan dicha evolución en Perú; debe ocurrir otra ola de contagios y llegarse a cifras acumulativas entre 2,9 y 3,36 millones de infectados y entre 215 y 255 mil fallecidos; las principales estrategias de mitigación deben dirigirse a garantizar el distanciamiento y aislamiento social, así como a incrementar el régimen de vacunación.

Abstract Introduction: The creation of 3D printed silicone models has several purposes, one of which is to provide augmented reality (AR), thanks to the imaging and visualization methods that serve as aids in “surgical planning”. They enable precise analysis of the anatomy at the site to be treated and can influence surgical strategy change or decision-making. Materials and methods: The present case report describes the surgical planning carried out with a 3D printed model, in a 40-year-old patient incidentally diagnosed with a T2aN0M0 CS I left kidney tumor, measuring 20 mm, that was slightly exophytic, with a RENAL Score of 4a. Results: Total surgery duration was 180 min, with a console time of 120 min, blood loss of 50cc, and warm ischemia time of 12 min. No drain was placed, hospital stay was 2 days, and there were no complications. Discussion: Visualizing the anatomic characteristics on the model enabled surgical programming to be carried out, along with guided dissection and selective clamping that did not involve the entire renal hilum. Three-dimensional models are based on multi-slice digital tomography images that are converted to real scale and then printed with different materials, achieving an anatomic representation of the organ to be treated. Conclusions: That type of planning favors better understanding of the surgical anatomy of the tumor and improved decision-making. Case series on different anatomic variations, as well as other organs, should be carried out.

Resumen Introducción: La creación de modelos impresos en silicón 3-D tiene varios objetivos, uno de ellos es el resultado de la realidad aumentada (AR), gracias a los métodos de imagen y de visualización como auxiliares en la planificación quirúrgica, ya que permiten un análisis preciso de la anatomía del sitio a tratar y pueden ser un punto de cambio de estrategia quirúrgica o incluso de toma de decisiones. Material y métodos: Reporte de caso de impresión de modelo 3D y realización de planeación quirúrgica en paciente de 40 años con diagnóstico de Tumor Renal Izquierdo T2aN0M0 EC I. Incidentaloma de 20 mm, discretamente exofítica con un RENAL Score de 4a. Resultados: Tiempo quirúrgico Total de 180 min; tiempo de consola de 120 min; sangrado de 50cc; tiempo de Isquemia Caliente 12 min; no se colocó drenaje; días de estancia hospitalaria 2; no se presentaron complicaciones. Discusión: La visualización de las características anatómicas en el modelo permiten programar y disecar de manera guiada y hacer un clamping selectivo y no de la totalidad del hilio renal. Los modelos tridimensionales están basados en imágenes multicorte de tomografía de los que la extracción digital es llevada a una representación de escala real y posteriormente es impresa en diferentes materiales, de tal manera que contamos con una representación anatómica del órgano que deseamos tratar. Conclusiones: Contar con este tipo de planeación favorece un mejor entendimiento de la anatomía quirúrgica del tumor y la toma de decisiones. Es necesario realizar series de casos para las diferentes variaciones tanto anatómicas como de otros órganos.

Abstract: Objective: To evaluate the efficacy of thermal fogging of a mixture of flupyrafirudone (26.3 g/L) and transfluthrin (52.5 g/L) against dengue, Zika y chikungunya Aedes mosquito vectors. Materials and methods: Groups of 15 caged Ae. aegypti (susceptible and pyrethroid resistant) mosquitoes were placed in living room, kitchen and bedroom inside houses, after which a dose of 2 and 4 mg/m3 of flupyradifurone and transfluthrine, respectively, was applied as thermal fog. After one hour of exposure mosquitoes were transferred to the laboratory and mortality was recorded after 24 h. Results: The mixture killed 97 to 100% of mosquitoes from the strains and the efficacy was similar independently of their place within the premises. Conclusions: The mixture of flupyrafirudone and transfluthrin applied as thermal fog is a promising tool to control Aedes mosquito populations independently of the pyrethroid-insecticide resistance status.

Resumen: Objetivo: Evaluar la efectividad de la mezcla de flupyradifurona 26.3 g/L y transflutrina 52.5 g/L aplicada como niebla térmica a mosquitos Aedes vectores de virus dengue, Zika y chikungunya. Material y métodos: Se colocaron grupos de 15 mosquitos de Ae. aegypti (susceptibles y resistentes a piretroides) dentro de jaulas, en sala, recámara y cocina. Posteriormente, se aplicó la mezcla de flupyradifurona y transflutrina dentro de las viviendas a una dosis de 2 y 4 mg/m3, respectivamente. Resultados: La mezcla de flupyradifurona y transflutrina causó mortalidades de 97 a 100% sobre las cepas de mosquitos Aedes y su efectividad fue la misma en los diferentes compartimentos de las viviendas. Conclusiones: La mezcla de flupyradifurona y transflutrina, aplicada en niebla térmica, es una herramienta prometedora para el control de poblaciones de mosquitos Aedes independientemente de su estado de resistencia a insecticidas.

ABSTRACT The massive adoption of no-tillage (NT), along with the simplification of the cropping sequences has led to physical and chemical degradation of soils. To recover degraded soils, cover crops have been proposed as an alternative to increase soil organic carbon (SOC) and to improve soil physical quality (SPQ). This study aimed (i) to determine the content of SOC and its physical and chemical fractions at different layers and positions, in a soil with a soybean crop under NT with and without winter cover crops, and (ii) to determine SPQ indicators in a soybean crop under NT with and without winter cover crops. Measures and samples were made on a field experiment in a typical Argiudoll of the Argentinean Pampas. Soil organic carbon, coarse and fine particulate organic carbon (POCc and POCf), mineral associated organic carbon (MOC), fulvic acids (FA), humic acids (HA), and humins (H) were determined. Soil physical quality indicators determined were: soil bulk density and total porosity from field samples, and saturated hydraulic conductivity, water-conducting macro and mesoporosity, and total porosity connectivity from field water infiltration data. After eight years, cover crops did not cause any observable change in whole SOC content, but significant differences were observed for some SOC fractions. Humic acids and POCc had 40 and 25 % increases, respectively, in the cover crop treatment. Mineral associated organic carbon and H decreased by 9 and 7 % in cover crop treatment. Soil physical quality did not improve after eight years of cover crops. This can be related to degradation processes after 20 years of soybean monoculture under NT, and to the low ability of Argiudolls to recover from physical degradation.

ABSTRACT Simulation models are efficient tools to predict the fate of different solutes in agricultural soils. This work aimed to compare measured and predicted glyphosate and AMPA (aminomethyl phosphonic acid; its main metabolite) contents in a soil under no-tillage (NT), and conventional tillage (CT); and to compare the predictions considering constant and time-variable hydraulic properties. Additionally, we evaluated the ability of the model to predict glyphosate and AMPA accumulation during the crop cycle. Hydrus 1-D code was used to predict the glyphosate and AMPA dynamics, considering constant and time-variable hydraulic properties during the studied crop cycle. In general, the prediction of glyphosate and AMPA distribution along the soil profile using HYDRUS 1-D was satisfactory; however, an overestimation of both compounds was observed in the first 0.20 m of the soil probably because of the preferential flow. Additionally, the accumulation process of glyphosate and AMPA in the soil during the crop cycle was underestimated by HYDRUS 1-D, as compared with the observed field data. Simulated data show that higher values of K0 increase the risk of glyphosate and AMPA vertical transport. The inclusion of temporal variation of hydraulic properties in glyphosate and AMPA simulation did not improve the simulation performance, showing that the model is more sensitive to the parameters related to the solutes. From the obtained results, HYDRUS 1-D code allowed to predict glyphosate and AMPA dynamics reasonably well in agricultural soils of the Argentinean Pampas region and is a potential model to give support in the analysis of the environmental risk of leaching and soil contamination.

Abstract Mexico present high rate of violence against women, which comes from the partner. The risk level assessment of intimate partner violence allows providing security measures to the victims and reducing the re-victimization. The aim was to validate the Severe Intimate Partner Violence Risk Prediction Scale (EPV-R) in the urban context of Chihuahua, Mexico. Methods. The scale was applied in 591 victims of violence, classified into two groups: severe and non-severe violence. An experts committee included three new items: psychological violence, economic violence and aggressor links with organized crime. The Internal consistency, the inter-observer concordance, the discriminative capacity of each of the items and the diagnostic efficacy were analyzed. All test were performed at the 95% of confidence level. Results. Adequate internal consistency (Cronbach’s alpha of 0.79) and good agreement between inter-observers (Kappa coefficient 0.79, p < 0.001; Intraclass Correlation Coefficient = 0.96, p = 0.001) were found. Of all 23 items, 20 showed adequate association capacity between severe and non-severe violence groups (p < 0.05), five items presented high capacity, 6 items moderated capacity and 11 items showed low capacity, assigning them a value of 3, 2 and 1 points respectively. The total score mean of the scale was higher in severe group than non-severe group, 22.7 ± 5.9 vs 12.1 ± 7.2 respectively (t = 14.6, p = 0.001). After several cutoff scores tested, a value of 21 combine the best sensitivity, specificity and diagnostic efficacy of the instrument with 70%, 87% and 79% respectively; also, an AUC of 0.86 was found (p = 0.001). From this viewpoint, three levels of severe violence risk were determined: low (0-8), moderate (9-20) and high (20-36). Conclusion. The EPV-R is a reliable and valid instrument to estimate the risk of serious violence against the couple in the urban context of Chihuahua, Mexico.

Resumen La valoración del nivel de riesgo de violencia permite brindar medidas de seguridad a las víctimas y disminuir la revictimización. El objetivo fue validar la escala de predicción de riesgo de violencia grave contra la pareja (EPVR) en población mexicana. Método. Se aplicó la EPV-R modificada a 591 víctimas de violencia, clasificadas en dos grupos: violencia grave y no grave. Se analizó la consistencia interna, la concordancia inter-observadores, la capacidad discriminativa de los ítems y la eficacia diagnóstica. Resultados. Se encontró una confiabilidad interna adecuada (alfa de Cronbach de 0.79); 20 ítems presentaron capacidad discriminativa entre violencia grave y no grave acorde al índice de discriminación y la prueba de chi-cuadrada (p < 0.05). Se observó una concordancia adecuada inter-observador con base en el índice Kappa (0.79, p = 0.001) y el coeficiente de correlación interclase (0.96, p = 0.001). A partir de una puntuación de 21, se encontró un AUC de 0.86 (p = 0.001), una sensibilidad de 70%, una especificidad de 87% y una eficacia diagnóstica de 79%. Conclusión. La escala EPV-R demostró ser un instrumento fiable y válido para estimar el riesgo de violencia grave contra la pareja, en la ciudad de Chihuahua, México.

Fractal geometry allows describing theoretically structures of diverse nature. From this it obtain the fractal dimension of fragmentation (D), which is related to the partitioning and scaling presented by them, and which has been used in the characterization and study of the size distribution soil particle (DTP). It was proposed to apply the fractal model and investigate the process of micro-structuring in six agricultural soils of the Pampean meadow that have contrasting DTP. The DTP and D were obtained under two pretreatments, one without organic matter (SMO), maximum dispersion, and the other with organic matter (CMO), thus preserving the microstructure. The fractal model applied to the DTP with the SMO pretreatment, in silty loam soils, was able to describe on average 98% of the mass analyzed; in sandy loam soil it adjusted to 50 μm, describing 38% of the mass, while the sandy loam soil did not adjust to the fractal model. With the larger sizes of the sands, they obtained D close to 3, showing Euclidean characteristics, not fractals. The DTP for the CMO pretreatment had similar behavior among the evaluated soils, compared to the SMO pretreatment, the percentages of the fractions corresponding to the clay and silt sizes decreased; and the percentage of the size of the sands increased. These fractions, CMO, were called "apparent clay, silt and sand". The D from the SMO pretreatment were greater than those obtained under the CMO pretreatment. The decrease of the D of the pretreatment CMO, was interpreted as an apparent thickening of the soil product of the microstructure by organic matter (OM). The fit between the contents of apparent clays vs OM was not significant (p = 0.37). The apparent silt fraction vs OM, adjusted significantly to a negative exponential function while the contents of the apparent sands vs OM adjusted significantly with a positive exponential function. The variations of OM significantly modify the microstructure in the silt and sand sizes while the fraction of clay size would be independent of the OM content of the soil, in the analyzed range. In temperate Pampas soils, with a proportion of clay + silt close to 90%, the OM by microstructure reduces the contents of clay and silt size particles, increasing the sand size to values close to 55% and these modifications can be interpreted using the model fractal.

La geometría fractal permite describir teóricamente estructuras de diversa naturaleza. De esta se obtiene, la dimensión fractal de fragmentación (D), la cual, está relacionada con el particionamiento y escalamiento que presentan las mismas, y que ha sido empleada en la caracterización y estudio de distribución de tamaño de partículas del suelo (DTP). Se planteó aplicar el modelo fractal e investigar sobre el proceso de microestructuración en seis suelos agrícolas de la pradera pampeana con DTP contrastantes. Las DTP y las D se obtuvieron bajo dos pretratamientos, uno sin materia orgánica (SMO), máxima dispersión, y otro con materia orgánica (CMO) conservando así la microestructura. El modelo fractal aplicado a la DTP con el pretratamiento SMO, en los suelos franco limosos, alcanzó a describir en promedio el 98% de la masa analizada; en el suelo franco arenoso ajustó hasta los 50 μm, describiendo el 38% de la masa, mientas que el suelo areno franco no ajustó al modelo fractal. Con los tamaños mayores de de las arenas se obtuvieron D próximas a 3, mostrando características euclideanas, no fractales. Las DTP para el pretratamiento CMO tuvieron similar comportamiento entre los suelos evaluados, comparado con el pretratamiento SMO, disminuyeron los porcentajes de las fracciones correspondientes a los tamaños arcilla y limo; y aumentó el porcentaje del tamaño de las arenas. A estas fracciones, CMO, se las denominó "arcilla, limo y arena aparentes". Las D a partir del pretratamiento SMO fueron mayores que las obtenidas bajo el pretratamiento CMO. La disminución de la D del pretratamiento CMO, se interpretó como un engrosamiento aparente del suelo producto de la microestructuración por materia orgánica (MO). El ajuste entre los contenidos de arcillas aparentes vs MO no fue significativo (p=0,37). La fracción limo aparente vs MO, ajustó significativamente a una función exponencial negativa mientras que los contenidos de las arenas aparentes vs MO ajustaron significativamente con una función exponencial positiva. Las variaciones de MO modifican significativamente la microestructuración en los tamaños limo y arena mientras que la fracción de tamaño arcilla sería independiente del contenido de MO del suelo, en el rango analizado. En suelos templados pampeanos, con proporción de arcilla+limo próximas al 90%, la MO por microestructuración, reduce los contenidos de partículas de tamaños arcilla y limo incrementando las de tamaño arenas a valores próximos al 55% y estas modificaciones pueden interpretarse empleando el modelo fractal.

Resumen En el presente trabajo de corte exploratorio analizamos las transformaciones de los tres ríos urbanos principales de la Zona Metropolitana de San Luis Potosí: el río Santiago, el río Españita y el río Paisanos. Desde un enfoque hidro-social, el análisis aborda las transformaciones físicas de los ríos en relación con el crecimiento urbano y con los cambios en la interacción y el significado que la sociedad otorga al recurso hídrico. Para llevarlo a cabo se realizó un mapeo interpretativo en el que se sobrepusieron capas con información histórica, sociodemográfica, geográfica e hidrológica. Además, se administraron entrevistas con informantes clave y se consultaron fuentes secundarias. Estos métodos permitieron reconstruir las transformaciones de los ríos desde las lógicas impresas, los usos del espacio y del agua y los tipos de agua que derivan de la relación dialéctica entre naturaleza y sociedad. Los hallazgos principales del trabajo indican que todos los cauces han sido modificados en beneficio del crecimiento urbano. Además, el vínculo social con los ríos como elementos naturales y fuentes de vida se ha roto; actualmente los cauces son percibidos como fuentes de contaminación e inseguridad, más útiles como elementos urbanos que naturales. Este cambio de percepción explica por qué los cauces se encuentran actualmente fragmentados de forma física y simbólica.

Abstract This exploratory study analyses the transformations of the three main urban rivers within the Metropolitan Area of San Luis Potosí: Rio Santiago, Rio Españita and Rio Paisanos. From a hydro-social perspective, the analysis focuses on the physical transformations of the rivers and their relationship with urban sprawl and on the meaning and interaction changes between society and the hydric resource. For the study, was conducted an interpretive mapping exercise overlapping layers with historical, socio-demographic, geographic and hydrological information. Additionally, interviews were administered to key informants and secondary sources were reviewed. These methods allowed to re-construct the rivers’ transformations to understand the logics employed, resulting space and water uses and the types of water derived from the dialectic interaction nature-society. The major findings of the research indicate that all three rivers have been diverted to benefit urban growth. Furthermore, the social bond with rivers as natural elements and sources of life has been broken; nowadays, riverbeds are perceived as sources of pollution and insecurity, more useful as urban elements than as natural landscape components. This perception shift explains the reason why river courses are currently fragmented in a physical and symbolical manner.