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Un análisis de cadena de valor de la pesquería de arrastre en el Pacífico mostró que más del 50 % de los empleos generados en esta pesquería son ocupados por mujeres, y que la mitad de estos son aportados por las platoneras del distrito de Buenaventura. Las platoneras son mujeres afrodescendientes comercializadoras de productos pesqueros basados en las capturas incidentales de esta pesquería y que hacen parte integral de la pesquería de arrastre. Desconociéndose el aporte a la economía local y al sector pesquero, este estudio describe el rol de las platoneras en la pesquería para realizar un mapeo de la cadena de valor sensible al género y nutrición. Para esto, se aplicaron entrevistas a 123 platoneras en cinco puntos de comercialización del distrito. El análisis mostró que ellas perciben en promedio $87.500 COP diarios. La edad promedio es de 50 años y 94 % se encuentran afiliadas al sistema de salud bajo régimen subsidiado. Las platoneras comercializan alrededor de 60 productos y su papel es clave para el dinamismo del sector pesquero, la economía y la tradición gastronómica local.

O mercado de trabalho é um dos ambientes mais afetados pela volatilidade das economias. Nesse contexto, o caso dos jovens é ainda mais dramático, sendo a faixa etária mais afetada por esses ciclos de expansão e depressão. Por outro lado, a qualificação profissional surge como mecanismo de resposta à maior competitividade entre os trabalhadores e a oferta dessas capacitações no Brasil, por muito tempo atrelada ao Estado, é cada vez mais relacionada ao “Terceiro Setor”. Assim, o presente trabalho busca avaliar, através de um modelo de regressão logit, quais características socioeconômicas impactam na probabilidade de entrada dos candidatos no projeto de capacitação profissional oferecido pelo Trilha Jovem Iguassu (mantido por uma entidade do Terceiro Setor) aos jovens do município de Foz do Iguaçu – PR. Com isso visa-se fomentar as discussões no meio acadêmico sobre o tema, bem como as tomadas de decisão dos policy makers envolvidos no planejamento, execução ou avaliação de programas similares. Dentre os resultados, destacam-se a maior probabilidade de entrada no projeto de jovens brancos, do sexo masculino, cujas famílias são beneficiárias do Programa Bolsa Família e que não falam inglês; e menor probabilidade de jovens com 16 anos de idade. Os resultados apontam para a necessidade de discussão dos critérios adotados atualmente no processo de seleção, a fim de verificar se os objetivos do projeto estão sendo atendidos.Palavras-chave: Jovens, Emprego, Programas sociais, Qualificação profissional, Econometria.

En Ecuador, la actual pandemia provocada por el COVID 19 ha despertado el interés y, de cierta forma, ha obligado a varias personas a emprender. Sin embargo, es interesante cuestionarse acerca de los aspectos positivos que invitan a emprender y conseguir el éxito, así como también los aspectos negativos que provocan deserción. El propósito de este estudio fue identificar los aspectos que motivan o desmotivan a este grupo de personas que abandonan su círculo de confianza para aventurarse a nuevos horizontes, conllevándolos al éxito o al fracaso, según las habilidades y proyecciones. Como resultado se identificó que los principales factores son el desconocimiento del proceso emprendedor, habilidades y experiencia, la dificultad para acceder a préstamos financieros, el miedo al fracaso y el desconocimiento del mercado, además de aspectos legales y regulaciones financieras. Palabras clave: Emprendimiento, COVID 19, factores de éxito, motivación, deserción.In Ecuador, the current pandemic caused by COVID 19 has aroused interest, and in a certain way has forced several people to undertake. However, it is interesting to ask yourself about the positive aspects that invite you to undertake and achieve success, as well as the negative aspects that cause desertion. The purpose of this study is to identify the aspects that motivate or demotivate this group of people who leave their circle of trust to venture to new horizons, leading them to success or failure according to skills and projections. As a result, it was identified that the main factors are ignorance of the entrepreneurial process, skills and experience, difficulty in accessing financial loans, fear of failure and ignorance of the market, in addition to legal aspects and financial regulations.Keywords: Entrepreneurship, COVID 19, success factors, motivation, desertion.

Introduction: The American Stroke Association Guidelines on acute ischemic stroke (AIS) thrombolytic treatment endorse the use of tenecteplase (TNK) weakly (IIb) based on moderate quality (B-R) evidence. The use of alteplase for AIS is strongly recommended (I) with high quality (A) of evidence. Despite this, many healthcare systems have transitioned to the use of TNK based on limited clinical trial data. Our study presents real world outcome data comparing AIS patients treated with TNK vs alteplase. Methods: Data were retrospectively abstracted from AIS patients treated with IV thrombolytic (IVT) or IVT and endovascular therapy (EVT) discharged between 1/1/2019-6/30/2022 . Patients were grouped into alteplase w/wo thrombectomy and TNK w/wo thrombectomy. Primary outcomes were discharge disposition, complications (sICH, serious systemic hemorrhage), door to needle and door to device times, treatment complications and post-EVT TICI score. Adjusted odds ratios (AOR) and 95% confidence intervals (95% CI) are reported for likelihood to receive IVT within 45 minutes and 30 minutes of arrival for the IVT group, adjusting for sex, race, admit NIHSS, and previous stroke. Results: 3733 patients were included in the IVT group: 90.7% received alteplase, 9.3% received TNK. 814 patients received IVT and EVT: 90% received alteplase and 10% received TNK. In the IVT group, the median [Q1, Q3] DTN for alteplase was 48 [35, 66] minutes TNK was 45.5 [34.75, 63.25] (p=0.067). There was no significant difference in the likelihood of receiving IVT within 45 minutes and 30 minutes between the two drugs. Patients with higher admit NIHSS were more likely to receive IVT within 45 minutes (AOR 1.031 95% 1.021, 1.041 p Conclusion: In our study there were no differences in benefit, risk, or treatment logistics between alteplase and tenecteplase when used in treating acute ischemic stroke. Recanalization of large vessel occlusion prior to endovascular thrombectomy was not analyzed but will be the subject of study in this cohort.

Despite the advantages and superiorities of compliant mechanisms and soft robots over rigid mechanisms, optimizing the stiffness of flexible links and dynamic properties of complex and high mobility designs is increasingly challenging. Additionally, the largest challenge in the design and modeling of such systems is understanding the deformation of the two bodies when connected along with their interaction in complex cases such as large deflecting buckling beams, especially for people who are new in the area. There exist several methods and techniques for obtaining kinematic relations as pseudo rigid body modeling (PRBM), first and second kind of Elliptica theory, discrete beam element method for simple geometries of compliant mechanisms, and nonlinear dynamical modeling of soft robots assuming using constant curvature spatial curves, and also machine learning. To address this issue, we present the user-friendly and open-access MATLAB Toolbox for the design and motion analysis of compliant mechanisms and soft robots. The developed toolbox serves as a platform to visualize the deformation of compliant joints and compliant beams (Module 1), visualize the displacement of various compliant mechanisms (Module 2), design simple and complex compliant mechanisms using the hinges and beams, and design and motion analysis of soft robots (Module 3).

Among the robotic systems, biomimetic robots performing fish-like locomotion have been the focus of much attention recently as there are many applications for swimming robots, including monitoring of underwater environments, detection of pollution, and disaster relief. This study presents the design and development of a biomimetic fish-like robot based on real carp locomotion. The robot has five main body parts including the head, soft neck, hinged body, compliant tail, and caudal fin. The head houses three ultrasonic sensors to guide the robot while connected to the body through two degrees of freedom (DOF) soft link resembling the neck vertebrate. The 2 DOF soft link enables the head to bend up, down, left, and right which is essential for controlling the soft robot’s direction. The body is connected to the soft tail using a quick return crank mechanism to actuate the tail. The tail integrates a soft tail and a rigid caudal fin. While all parts of the soft fish-like robot are 3D printed using polylactic acid (PLA), thermoplastic polyurethane (TPU), the mold is made from silicone rubber to waterproof. The ultrasonic sensors are utilized to detect obstacles so that the robot may maneuver around. The swimming pattern only for two-dimensional motion is tested in the air and underwater. According to the experimental results, the proposed robot better imitates the fish through its soft 2 DOF link and tail.

Soft parallel robots are among the latest advancements in the field of soft robotics with wide range of applications. Most of the existing soft robotic systems comprise from serial soft arms which can provide high degrees of freedom (DOF), but suffer from low stiffness, and limited payload due to their soft structure. To address these issues recently researchers have introduced soft parallel robots. Similar to their rigid counterparts, soft parallel robot will have higher blocking force, stiffness, and accuracy. We have previously introduced two, and three DOF soft parallel robots and in the current work we will introduce a novel six DOF robot named 3-universal-spherical-revolute (3USR) soft parallel robot. This robotic system is consisted of three closed-loop kinematic chains. Each chain includes a soft active arm with two DOF which is connected to a compliant passive link through soft joints. This configuration provides six DOF for the soft robot (x, y, z, roll, pitch, yaw). The prototype of the robot is 3D printed using NINJA flex, thermoplastic polyurethane (TPU), and polylactic acid (PLA). Each soft active arm consists of a two DOF tendon driven soft actuator which is 3D printed using NINJA flex and are actuated using two servo motors. Two types of soft joints are used namely soft spherical and revolute joints. The shape and size of the soft joints are optimized so that the robot will achieve six DOF. MATLAB Simscape model is used to simulate the dynamical response of the mechanism for various inputs.

The vast majority of undergraduate engineering students struggle to acquire a deep understanding of complex topics presented in mechanical vibrations and control theory courses due to their highly mathematical nature, limited resources on the use of commercially available turn-key laboratory equipment, and lack of innovative teaching tools to improve student understanding. In this study, we developed open-source standalone virtual laboratory exercises for vibrations and control theory courses using Matlab Simscape. The virtual labs enable students to change the system parameters, develop a feel of the material, and record and observe the system response through mechanics explorer.

El objetivo de este artículo es: a) rescatar las experiencias, sentires y perspectivas que adop­tan los jóvenes, en torno al posicionamiento que asumen como sujetos políticos que aportan a la construcción de paz por medio del arte. Con base en un enfoque cualitativo y hermenéu­tico- se realizó un grupo focal con diez jóvenes que pertenecen a la Red Somos Generación de Verdad -Macro territorial Bogotá-Soacha- de la Comisión para el Esclarecimiento de la Verdad, la Convivencia y la No Repetición (CEV). Se encontró en los repertorios obtenidos que el arte representa para ellos una herramienta y una posibilidad de esperanza, mediante la cual generan espacios de realidad-ficción. Además, se concluyó que, a través del arte han logrado realizar una re-lectura, una re-interpretación y una re-significación de las ciudada­nías y de las dinámicas sociales emergentes que dotan de sentido su cotidianidad, posibili­tando la aparición de otros mundos, que se oponen a las prácticas de violencia y exclusión legitimadas históricamente en Colombia.

Resumen: El insomnio es uno de los trastornos del sueño más prevalentes de la población mundial, presentando una prevalencia del 10-15% de la población general mundial. El insomnio de tipo crónico, es decir, aquel que persiste por más de 3 meses, afecta seriamente la salud del individuo y su calidad de vida, constituyendo un importante problema de salud pública. El enfoque terapéutico del insomnio es multidisciplinario y dependerá de su etiología. Sus objetivos fundamentales son mejorar la calidad del sueño y los síntomas diurnos, de modo de contribuir a una mejor salud, calidad de vida y funcionalidad del afectado. Según diferentes organismos internacionales Academia Americana de Medicina del Sueño (AASM) y las guías europeas), el tratamiento de primera línea para el insomnio crónico del adulto son las medidas no farmacológicas, lo que comprende la terapia cognitiva conductual (TCC-I). El tratamiento farmacológico solo debiese considerarse si la TCC-I no está disponible o si no es efectiva; o al inicio de la TCC-I. Si bien existe un largo listado de medicamentos que pueden usarse para el insomnio crónico, cuyo objetivo sería mejorar la duración y continuidad del sueño con un perfil aceptable de efectos secundarios, se hace relevante destacar que el “medicamento ideal” no existe. Estudios futuros destinados a comprender mejor la neurobiología y la genética del sueño, así como la fisiopatología del insomnio, son cruciales para desarrollar un tratamiento farmacológico específico que sea curativo y personalizado. Summary: Insomnia is one of the world's most prevalent sleep disorders, presenting a prevalence of 10-15% of the general world population. Chronic insomnia, i.e., that lasts longer than 3 months, has a serious impact on an individual's health and life quality, therefore representing a mayor public health problem. The therapeutic approach for insomnia is multidisciplinary and depends on its etiology. Its primary objectives are to improve both sleep quality and symptoms appearing during the day, in order to enhance the patient's health, quality of life and functionality. According to different international organizations (American Academy of Sleep Medicine and European Guides), the first line treatment for chronic insomnia in adults are non-pharmacological measures, which include cognitive conductual therapy (CCT). Pharmacological treatment must only be considered if CCT is unavailable or ineffective. Moreover, using drugs at the beginning of CCT might be taken into account. Although there is a long list of drugs that can be used for chronic insomnia, which are able to improve sleep duration and continuity with an acceptable profile of side-effects, it is important to mention that the “perfect medicament” does not exist. Future studies aimed for a better understanding of neurobiology and sleep genetics as well as insomnia's physiopathology are crucial to develop a specific pharmacological treatment that is healing and customized.

La Cultura Organizacional (CO) ha tomado mayor relevancia en las últimas décadas, convirtiéndose en un elemento clave para el diseño de la estrategia corporativa, dado que en su esencia están contenidos los principios, creencias y valores que modelan los comportamientos y conductas que se presentan al interior de las organizaciones. Considerando lo anterior, en esta investigación se presentan resultados que evidencian la importancia del modelo de Cameron & Quinn y la aplicación de su herramienta OCAI, como uno de los instrumentos para identificar tipos de cultura en las organizaciones, en asociación con otras herramientas estadísticas, entre las cuales nombramos el Análisis de Componentes Principales (ACP), la Función VarImp y las redes neuronales, con el fin de lograr correlacionar los resultados en la identificación del tipo de cultura organizacional, predominante en la Institución Educativa José Holguín Garcés, permitiendo suministrar información con menor sesgo de subjetividad y proporcionando mayor grado de veracidad. Es así como los resultados obtenidos de esta investigación reflejan mayor incidencia de la cultura de tipo Jerárquica en la institución educativa, sin dejar de mencionar que los tipos de cultura Clan, Mercado y Adhocrática también tienen gran representación, según los resultados arrojados en la investigación. Adicionalmente, es necesario indicar que existe coherencia en los resultados obtenidos, tanto en la aplicación del OCAI, como de las herramientas APC y VarImp, donde la participación del tipo de cultura jerárquica presenta mayor nivel de predominancia.

This paper reports on Simscape modeling and experimental validation of compliant mechanisms and soft robotic systems. During the past decade, there has been a lot of advancements in terms of the development of novel soft robotic systems, actuators, and sensors. However, efficient modeling of these systems is still a challenge for researchers. This is due to the existence of nonlinearities such as large deformation in the structure of soft robotic systems and compliant mechanisms. While analytical models can be used for conventional rigid robots, the application of these models for soft robots is limited. Simscape is an efficient tool for modeling soft robotic systems and compliant mechanisms as it can take into account large deformation. To validate the developed Simscape models we used a 6 DOF electromagnetic position sensor for each of the example systems such as a compliant bistable mechanism, compliant linear actuator, and a soft Delta robot.

Marine and coastal ecosystems are characterized as highly productive areas in terms of the benefits they provide to humanity, with food provision being one of the most important. In 2018, in the Cispata Integrated Management District (DMI Cispata), due to the decrease in fishing resources, artisanal fishermen signed agreements for the recovery of the resource; however, they have not been implemented for various reasons. This study shows the viability of a Payment Scheme for Environmental Services as an alternative to induce compliance with fishing agreements. The analysis developed here indicates that the DMI Cispata fulfills the necessary conditions to implement this economic instrument benefiting 20 fishing organizations in the area. RESUMEN Los ecosistemas marinos y costeros se caracterizan por ser zonas muy productivas en términos de beneficios que proporcionan a la humanidad, siendo el servicio de aprovisionamiento de alimento uno de los más importantes. En 2018, en el Distrito de Manejo Integrado Cispata (DMI Cispata), Córdoba, a raíz de la disminución de recursos pesqueros, los pescadores artesanales firmaron acuerdos para la recuperación del recurso; sin embargo, no han logrado implementarse por diversas razones. El presente estudio muestra la viabilidad de un esquema de Pago por Servicios Ambientales como alternativa para inducir al cumplimiento de los acuerdos pesqueros. El análisis aquí desarrollado indica que el DMI Cispata cumple con las condiciones necesarias para implementar este instrumento económico beneficiando a 20 organizaciones pesqueras del área.

The distribution of Human Papilloma Virus (HPV) genotypes is not homogeneous among the infectedcells in a specific anatomical site. Thus, we conducted a prospective cross-sectional studywith 2,130 Mexican men and women aged 16 to 80 years. We described the prevalence of HPVgenotypes at the oropharyngeal cavity, anus, and urogenital sites. The most prevalent genotypes inwomen were HR-HPV 66 (5.6%), 16 (4.2%), 59 (4.3%) and LR-HPV 6 (10.1%); for men, HR-HPV16 (4.2%), 53 (3.8%), 66 (3.5%) and LR-HPV 6 (14.1%). In the cervix the most frequent genotypeswere: 6 (7.7%) and 66 (4.6%); vagina 6 (0.4%) and 16 (0.4%); genital wart 6 (5.9%) and 11 (2.7%);external genitalia 6 (0.5%) and 66 (0.5%); oropharyngeal cavity 6 (0.06%) and 66 (0.05%). In bothgenders, the most frequent genotype was HPV 6. The prevalence of HPV genotypes 31 (p=0.016),52 (p=0.049), 56 (0.036), 6 (p0.0001) and 11 (p0.0001) showed significant differences when comparinggenders. The kappa analysis demonstrated that in males, the HPV genotypes in the urethra/balanopreputial sulcus and urethral/genital warts had moderate concordance. In conclusion, HPVgenotyping screening tests among anatomical sites should be performed simultaneously to reinforcecurrent strategies, as well as for the development of vaccines and the discovery of oncogenic potentialfor genotypes that are not commonly analyzed.

Most studies on psychosocial stress among Hispanics have focused on risk factors. To better understand psychosocial stress among this population, this study aimed to examine components of bicultural identity integration and bicultural self-efficacy, that may be associated with lower psychosocial stress among Hispanic emerging adults (ages 18–25). This aim was tested on a cross-sectional sample of Hispanic emerging adults (M(age) = 21.30, SD = 2.09) that included 200 participants (Arizona n = 99, Florida n = 101). The sample included men (n = 98) and women (n = 102). Most participants were US-born (70%), college students (69.5%), and of Mexican heritage (44%). Standardized coefficients from a hierarchical multiple regression model indicate that higher levels of the bicultural harmony component of bicultural identity integration (β = −0.26, p < 0.001) and the social groundedness component of bicultural self-efficacy (β = −0.23, p < 0.01) were associated with lower levels of psychosocial stress. To our knowledge, this is the first study to examine components of bicultural identity integration and bicultural self-efficacy and their respective associations with psychosocial stress among any racial/ethnic group. Thus, more studies are needed to replicate our findings to determine if bicultural identity integration and bicultural self-efficacy should be considered in psychosocial stress interventions for Hispanics.

The Chaco Region is the third biogeographic and morpho-structural territory of South America after the Amazon and Cerrado savannahs. This region is one of the few areas in the world where the transition from the tropics to temperate zones does not consist of a desert but of semi-arid woodlands and savannahs. The modern biodiversity patterns of the region were severely affected by the climatic and environmental changes that occurred during the Quaternary. Remains of an extinct megamammal Neosclerocalyptus sp. (Upper Pleistocene) and charred fossil woods inside of sedimentary nodules, was recently discovered in Chaco Argentina. The aim of paper is the paleoenvironmental reconstruction of quaternary sedimentation in the western Chaco through the taxonomic identification of charred woods and siliceous microfossils analysis. Twenty-three charcoal fragments related to Anacardiaceae, Apocynaceae, Fabaceae, Rhamnaceae and Malvaceae were identified. The phytolith analysis showed that Poaceae elements were the most abundant compared to the other herbaceous and non-herbaceous elements, along with algae and sponge microfossils. Eco-anatomic features of the charcoals and the microfossil remains suggest that environment and climate conditions existed in the area during the Upper Pleistocene were similar to the current one. Finally, the results reveal the presence of natural wildfires during the Quaternary in the region.

Students taking traditional undergraduate level engineering courses not only struggle with highly complex concepts but also struggle in linking the physical meaning of the derived mathematical equations. In this study, we developed a standalone and user-friendly Matlab Simscape Graphical User Interface (GUI) program to visualize the concepts presented in the undergraduate level helicopter dynamics course. The developed GUI program enables students to change the parameters of the blade including the rotor radius, blade chord, type of airfoil, material properties, the weight of the aircraft and analyze the effect of the parameter on the performance of the helicopter rotor. The program uses motion dynamics to simulate the blade movement in hover and forward flight. The Simspace GUI program is composed of four modules starting with a simplistic beam model. In the first module, the blade is considered as a simple cantilever beam where an input point load is applied at the tip of the blade either vertically down or at an angle. In the second module, the force is replaced by a radially distributed load that simulates lift distribution along the span of the blade. In the third module, the distributed load is applied to various types of airfoils ranging from symmetrical NACA airfoil to supercritical airfoils. In the fourth model, the sectional velocities vary as a function of azimuth, and the forward-moving rotor is simulated.

The first pre-Quaternary representative of Alismataceae from South America is reported based on achenes of Sagittaria montevidensis from the Palo Pintado Formation (upper Miocene) in the south of Salta Province, Argentina. Achenes are laterally compressed, have a lateral beak and a single recurved seed inside them. The fruits were found both in the base (10 Ma) and the top of the formation (~5 Ma), suggesting similar environmental conditions during this time period. A cursory review of the Alismataceae family in the fossil record, with a special interest in those South American reports is given. During the Oligocene–Miocene Sagittaria may have arrived from tropical Africa to South America and thence to North America.

Background Snoring is a main concern in patients who consult an otolaryngologist (ENT physicians) and patients who have cardiovascular comorbidities or excessive daytime sleepiness who usually consult with other specialists. The aim of this study was to describe the clinical differences in patients with obstructive sleep apnea (OSA) referred from ENT or other specialists. Methods A prospective study was carried out between June 2015 and July 2018 in a tertiary center. We included patients with suspected OSA referred by the Home Sleep Apnea Test (HSAT) from different specialties such as ENT or other specialties. The main outcome measures of our study were demographic characteristics, clinical characteristics, sleep questionnaire results and HSAT results between OSA patients referred from ENT or other specialists. We used a t-test and chi-squared test for analysis. The diagnostic accuracy of the sleep questionnaires was achieved using receiver operating characteristic (ROC) curve and the area under the curve (AUC). Results A total of 481 patients were included. OSA was occurred in 82.4% of the subjects (90 in ENT and 306 in other specialties). Patients with OSA referred from other specialists were older than ENT patients (55 ± 13 vs 44 ± 12; p p = 0.015) and more positional apnea (62% vs 39%, p = 0.002). In this group, the STOP-BANG questionnaire showed an AUC 0.695 vs AUC 0.804, and for sensitivity, the best cutoff was 4 points. Patients referred from otorhinolaryngology are different from those referred from other specialties. Clinical evaluation and screening of OSA should be patient-centered according to these clinical findings.

Xenarthra is an endemic South American lineage of mammals, probably the sister clade of the other placental mammals. The oldest records of Xenarthra are from the latest Paleocene, although its current diversity is much lower than that recorded in some intervals of the Cenozoic Era. A new Neogene Xenarthra (Pilosa and Cingulata) assemblage from two localities of the Argentine Eastern Puna (Calahoyo and Casira) is described. The newly recorded taxa—Cingulata, Dasypodidae, Eutatini: Stenotatus sp. indet. and Eutatini indet., Euphractini: Macrochorobates scalabrinii (Moreno and Mercerat, 1891), and Tardigrada, Mylodontinae: cf. Simomylodon sp. indet. and Simomylodon cf. S. uccasamamensis Saint-André et al., 2010—and those already published from Calahoyo—Cingulata: Macrochorobates chapadmalensis (Ameghino, 1908), Eosclerocalyptus sp. indet., and Tardigrada, Megatheriidae: Pyramiodontherium bergi (Moreno and Mercerat, 1891)—suggest a middle–late Miocene age for the fossil-bearing levels. In Calahoyo, the presence of Stenotatus sp. indet., in addition to some rodents currently under study in the lower levels, suggest a closer similarity with the palaeofauna of Cerdas (southern Bolivia), probably involving the last part of the Miocene Climatic Optimum. The Xenarthra recorded in the middle and upper levels of Calahoyo and Casira suggest a late Miocene–Pliocene age. A comparative analysis between Calahoyo and Casira highlights the absence of Cingulata in the latter and a high diversity in the former. This situation probably indicates different paleoenvironmental conditions. Finally, we present the first certain record of the genus Simomylodon Saint-André et al., 2010 in Argentina, which includes the oldest record of dermal ossicles for sloths in South America.

El café (Coffea arabica L.) es un cultivo muy importante para el desarrollo del centro y sur de México: 70% del área cultivada se encuentra bajo manejo tradicional. Por la relevancia de estos agroecosistemas el objetivo fue identificar prácticas agroecológicas (PA)y su influencia en la fertilidad del suelo en sistemas de café de Xolotla, Puebla. Para identificar PA se aplicó una encuesta a 79 productores; para determinar la fertilidad del suelo se realizaron análisis fisicoquímicos con base en la NOM-021-SEMARNAT; además, se analizó la concentración bacteriana total. Se encontró que 71% de las prácticas que se usan en el manejo del cafetal son agroecológicas, tienen relación positiva con el rendimiento y con los contenidos de nitrógeno, potasio y calcio del suelo, así como con la concentración bacteriana del suelo. Se concluye que las PA favorecen el rendimiento y la fertilidad del suelo en el sistema agroforestal café

The Argentinean Mesopotamian region is a plain limited by large rivers, with an interesting environment history and climate changes, especially during late Neogene and Quaternary periods. Within the Mesopotamia, Corrientes Province is particularly attractive due toits current vegetation and geomorphological characteristics where the Eastern-Northwestern migration of the Paraná River has played an important role. This migration in turn, allowed the sedimentation of the main geological units in the Pliocene -Pleistocene interval. The outcrops of the Ituzaingó (Pliocene) and Toropí/Yupoí (late Pleistocene) formations are widely distributed in Corrientes, and include numerous fossil remains of plants, invertebrates, and vertebrates (mainly mammals). Despite the paleontological and stratigraphic studies carried out, the data are still insufficient to reconstruct how the environments varied and how the migration of the Paraná River could have affected the vegetation during the last part of the Cenozoic. In this contribution, the first detailed study of the phytolith assemblages is accomplished, characterizing the Ituzaingó and Toropí/Yupoí formations in order to infer the palaeoclimatic and vegetation changes during the late Cenozoic in this area of the Mesopotamian region. Four sampling localities (BV1, BV2, E1, and E2) were selected in two sites (Bella Vista and Empedrado). The recovered associations were useful for environmental reconstructions. Both formations are fluvial deposits related at different times to the current Paraná River. The phytolith assemblages of the Ituzaingó Fm. evidence the different ways in which the biosilica elements were affected by pre and post-depositional processes. The Toropí/Yupoí Fm. shows well-preserved assemblages that suggest heterogeneous vegetation communities, with wetlands and grasslands to savannas and forests on the floodplain environments under seasonal subtropical climates. Fil: Contreras, Silvina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Departamento de Biología. Cátedra de Paleontología; Argentina Fil: Zucol, Alejandro Fabián. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Méndez, Cecilia Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Zurita, Alfredo Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas, Naturales y Agrimensura. Departamento de Biología. Cátedra de Paleontología; Argentina

Leopardus is a genus that, despite currently being widely distributed in South America, shows until now a fragmentary fossil record. Among Leopardus, L. pardalis is the largest species, having an historical range that includes tropical and subtropical habitats from southern U.S.A. to southern South America but, as usual in the ocelot lineage, fossil remains that can be interpreted with certainty are restricted to the Late Pleistocene of southern U.S.A. and Brazil. Here we present a new record (a fragment of right maxillary plus zygomatic with P4–M1; incomplete left mandible with the coronoid process, part of c1 alveolus and p3–m1; isolated right c1) from the Late Pleistocene of Arroyo Toropí, Corrientes province, Argentina. The bearing level was dated with Optically Stimulated Luminescence (OSL) to 98.4 ka (Marine Isotopic Stage, MIS 5c). Present environmental requirements of L. pardalis and climatic reconstructions carried out here suggest a compatible scenario with MIS 5 for this fossil, which is concordant with the associated dating (ca. 98.4 ka). Leopardus pardalis appears to be part of a subtropical fauna, with Tayassu pecari and Euphractus sexcinctus, which inhabited the region during warm and wet climatic events of MIS 5c. Phytoliths and other vertebrates are congruent with its presence, since the inferred conditions are similar to the present one. The new record is relevant not only because it is the first fossil record of the species for the Pleistocene of Argentina, but also because it is placed 1800 km south of the closest accurately identified published fossil.

During normal neuronal activity, ionic concentration gradients across a neuron’s membrane are often assumed to be stable. Prolonged spiking activity, however, can reduce transmembrane gradients and affect voltage dynamics. Based on mathematical modeling, we investigated the impact of neuronal activity on ionic concentrations and, consequently, the dynamics of action potential generation. We find that intense spiking activity on the order of a second suffices to induce changes in ionic reversal potentials and to consistently induce a switch from a regular to an intermittent firing mode. This transition is caused by a qualitative alteration in the system’s voltage dynamics, mathematically corresponding to a co-dimension-two bifurcation from a saddle-node on invariant cycle (SNIC) to a homoclinic orbit bifurcation (HOM). Our electrophysiological recordings in mouse cortical pyramidal neurons confirm the changes in action potential dynamics predicted by the models: (i) activity-dependent increases in intracellular sodium concentration directly reduce action potential amplitudes, an effect typically attributed solely to sodium channel inactivation; (ii) extracellular potassium accumulation switches action potential generation from tonic firing to intermittently interrupted output. Thus, individual neurons may respond very differently to the same input stimuli, depending on their recent patterns of activity and/or the current brain-state., Author summary Ionic concentrations in the brain are not constant. We show that during intense neuronal activity, they can change on the order of seconds and even switch neuronal spiking patterns under identical stimulation from a regular firing mode to an intermittently interrupted one. Triggered by an accumulation of extracellular potassium, such a transition is caused by a specific, qualitative change in of the neuronal voltage dynamics—a so-called bifurcation—which affects crucial features of action-potential generation and bears consequences for how information is encoded and how neurons behave together in the network. Also, changes in intracellular sodium can induce measurable effects, like a reduction of spike amplitude that occurs independently of the fast amplitude effects attributed to sodium channel inactivation. Taken together, our results demonstrate that a neuron can respond very differently to the same stimulus, depending on its previous activity or the current brain state. This finding may be particularly relevant when other regulatory mechanisms of ionic homeostasis are challenged, for example, during pathological states of glial impairment or oxygen deprivation. Finally, categorization of cortical neurons as intrinsically bursting or regular spiking may be biased by the ionic concentrations at the time of the observation, highlighting the non-static nature of neuronal dynamics.

Agroecological fairs have been positioning themselves as an alternative form of food marketing, based on the principle of sustainable production and in support of Family Farming as a production model. This essay aims to describe the formation and operation of this type of fairs within university institutions, through the case study of the Agroecological Fair of the Federal University of Latin American Integration (UNILA), located in the city of Foz de Iguazu, state from Parana, Brazil. A qualitative methodology was used, handling the interview –structured and exploratory-, photographic record and bibliographic review as techniques. As a result, a great cooperation network was detected between the economic actors of the fair, from which close personal relationships emerge, a factor that contributes to the management of conflict points and has allowed the reproduction of said market. Thus, it is concluded and recommended the implementation of projects of this nature within the institutions that, later, could be extrapolated to the external community, thus supporting small farmers and in turn promoting the implementation of public policies for this sector within the communities where they develop.

The landscape is the sum of natural and human elements. The presence of these elements, their distribution and interaction are combined throughout time to give shape to a particular place. In this context, water plays a fundamental role in the configuration of sandy hills landscape in Corrientes province, both originally and the modeling evolving over time, nowadays manifested by spatial patterns. The aim of this paper is to show the evolution of sandy hill region from the late Pleistocene to the present. The results were obtained due to the comparisons between the environmental reconstructions of the paleontological studies and the current situation of the region, besides the application of spatial analysis with geographic information systems and the knowledge of their shallow lakes distribution, since they constitute the main natural element of the landscape. The Corrientes landscape described to the Late Pleistocene is very similar to current landscape mainly to the water availability and the vegetal distribution. Using digital elevation models a topographic gradient in the sandy hills was observed and it showed decreases from the Paraná River alluvial fan apex to its base, with E-W or NE-SW direction. The Sandy Hill Landscape of Corrientes is one of the most important regions of Argentina due to their density, quantity, and distribution of the shallow lakes on the landscape.

The most northern fossil record of Panthera onca (LINNAEUS, 1758) from Argentina is here reported. The specimen, PVE-F 130, represented by an articulated and well preserved cranium and mandible, atlas and a fragment of left humerus, was exhumed from levels assigned to the Río Bermejo Formation (late Pleistocene-early Holocene; ca. 12.0-9.7 ka), near Villa Escolar, Formosa Province. The associated paleofauna, comprised mostly of large and megafaunal mammals, has a clear taxonomic similarity to that of the Pampean region of Argentina, and suggests open arid to semiarid environments. Indeed, previous analyses of plant remains associated with these vertebrates support the predominance of mega/mesothermal grasslands characterized by C3/C4 grass species. Fil: Rodriguez, Sergio Gabriel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Méndez, Cecilia Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Soibelzon, Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; Argentina Fil: Soibelzon, Leopoldo Héctor. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata; Argentina Fil: Contreras, Silvina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Friedrichs, Juan. Museo Provincial de Ciencias Naturales; Argentina Fil: Luna, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Zurita, Alfredo Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina

En la actualidad, el mega abanico aluvial del rio Parana constituye una region muy significativa en cuanto a la heterogeneidad de humedales; cuyos origenes, distribucion, amortiguacion hidrica y respuestas morfometricas a la variabilidad climatica local son tan complejas como diversas. En este sentido, se vincula el desplazamiento del rio Parana con los procesos que originaron los cursos de agua autoctonos y la disposicion de grandes extensiones anegadizas. No obstante, no ocurre lo mismo con las lagunas que se encuentran sobre las lomadas arenosas, donde los antecedentes son escasos o bien se realizan hipotesis en funcion de su morfologia, sin tener en cuenta, por ejemplo, las dinamicas naturales de las lagunas en relacion a las fluctuaciones en los niveles de agua. El objetivo de este trabajo es contribuir con los conocimientos sobre los procesos que originaron a las lagunas de lomadas arenosas ubicadas en el mega abanico aluvial del rio Parana teniendo en cuenta la dinamica propia de estos cuerpos de agua. Los resultados de este trabajo permitieron conocer que no solo existe un unico proceso original, sino que por el contrario, la deflacion, la segmentacion de pequenos cursos de agua, el pseudokarst y las interacciones entre ellos, serian los responsables de su genesis, distribucion, profundidad y alineamientos.

The Gran Chaco Americano is a large subtropical plain and one of the major biogeographic and morphostructural territories of South-America. Eastern Chaco is the wettest sector of the Gran Chaco and has heterogeneous environments. It includes different types of woodlands and forests together with savannahs, grasslands and wetlands. These vegetation patterns have been proposed to be the result of the Quaternary alluvial plain dynamics and the intensive migration of the Chacoan main rivers. Fossil records-that show change-are scarce and most of them come from the Fidelidad Formation (late Holocene). This Formation is located on the Bermejo River natural levees near the Villa Escolar Town (Formosa Province, Argentina). Fern fossils discovered in this Formation correspond to heterosporous aquatic ferns (Salviniaceae). The impressions were assigned to Salvinia cf. minima Baker 1886. These correspond with orbicular to elliptical leaves, with a smooth margin, and both the apex and the base are rounded. The base bears a slightly developed petiole. The venation pattern is dichotomous with anastomoses forming areolas. Generally, four tubercles (trichome bases) per areola are observed. The massulae and spores correspond to Azolla cristata Kaulfuss 1824. The massulae are rounded, oval or kidney-shaped and have septate glochidia. Spores are trilete and spheroidal. The floating ferns Salvinia and Azolla are good indicators of open fresh-water or wetlands paleo-environments. Hence, the lower levels of the Fidelidad Formation are associated with mostly calm freshwater bodies such as rivers, streams or wetlands, which are closely related to the activity of the Bermejo River during the late Holocene. These aquatic fern fossils provide new insights into paleoenvironmental conditions and increase the paleontological richness of the Eastern Chaco.

Objective: Of this study is to describe, based on dissections of anatomical pieces, the anatomical components of the Craniomandibular Joint Complex (CMJC). Materials and Methods: Eighteen half-heads of anatomical preparations belonging to Venezuelan human adults, previously treated with 10% formaldehyde and preserved in Gerdex ® undiluted for 6 months, prior to manual practice, were used. Consequently, the elements were dissected following the protocol of the Faculty of Dentistry of the University of Los Andes and particularizing the anatomical pieces in order to broach the different nature of the elements that constitute the CMJC. Results: The anatomical dissection was able to contrast the referred from a theoretical point of view in relation to what can be evidenced in a surgical intervention, illustrating the anatomical content that it has in normal conditions. The elements of the CMJC mostly coincide remarkably with what is described in this research, therefore, the solid knowle

In the Corrientes Province, the Parana River ran through different sections of the alluvial fan, forming sandy hills. Currently, over sandy hills a large number of small circular shallow lakes is developed. They were classified considering a qualitative description of aerial photographs and satellite images. However, the studies about the distribution, size, morphometric features and functionality of the shallow lakes only confined to specific case studies. Therefore, in order to obtain further information from the region that contains these water bodies, greater knowledge about the shallow lakes will be generated. The results of this paper allowed knowing the distribution of 38,926 shallow lakes, which account for 20% of the landscape surface. 72% of the total of shallow lakes has a circular shape and the remaining 28% has sub-circular and triangular shapes. An E-W distribution of shallow lakes is observed, where the most complex forms are distributed to the East and the simple/circular shapes increase toward the West. Major topographic differences allow greater lagoon interconnections and therefore complex shapes. On the contrary, western flatter reliefs contributes to the segmentation of lagoons. Statistical analysis of the morphometric variables of the shallow lakes according to the topography of the sandy hills, has classified in different sections mega alluvial fan of the Parana river.