246 research outputs found

    Small farmers' perception of factors influencing regional chemical control of Diaphorina citri

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    Regional Control Areas (RCAs) have been implemented in Mexico as a strategy to delay the spread of Candidatus Liberibacter asiaticus, the causal bacterium of the disease known as Huanglongbing (HLB). The implementation of an effective management of the vector insect, Diaphorina citri in the RCAs requires the knowledge, acceptance and coordinated engagement of small agricultural producers. This research assessed the perception and knowledge of 62 citrus growers regarding the operational, sociocultural and environmental factors influencing chemical control of D. citri in four RCAs within Veracruz State. According to their responses, the following factors have been identified as the operational factors with the highest influence on the effectiveness of insecticides against D. citri within RCAs: the lack of knowledge about the use of surfactants, application speed, poor calibration of sprayers and incorrect water quality. The most significant sociocultural factors are the general unawareness of the pest and the safe and proper application of pesticides. The most relevant environmental factors during application: temperature, relative humidity, and wind speed. Sociocultural index correlated with the perception of effectiveness. Therefore, it becomes necessary to consider differences among citrus growers in each region and setting out the most appropriatestrategies for vector and disease management. Highlights Some operational practices that citrus growers are not aware of may influence their perception of chemical control. The sociocultural context of growers determines their decision-taking on insecticide applications. During the application of insecticides in regional control areas (RCAs), growers do not take into account weather conditions. The effective management of D. citri requires a coordinated engagement of small growers' in RCAs.Regional Control Areas (RCAs) have been implemented in Mexico as a strategy to delay the spread of Candidatus Liberibacter asiaticus, the causal bacterium of the disease known as Huanglongbing (HLB). The implementation of an effective management of the vector insect, Diaphorina citri in the RCAs requires the knowledge, acceptance and coordinated engagement of small agricultural producers. This research assessed the perception and knowledge of 62 citrus growers regarding the operational, sociocultural and environmental factors influencing chemical control of D. citri in four RCAs within Veracruz State. According to their responses, the following factors have been identified as the operational factors with the highest influence on the effectiveness of insecticides against D. citri within RCAs: the lack of knowledge about the use of surfactants, application speed, poor calibration of sprayers and incorrect water quality. The most significant sociocultural factors are the general unawareness of the pest and the safe and proper application of pesticides. The most relevant environmental factors during application: temperature, relative humidity, and wind speed. Sociocultural index correlated with the perception of effectiveness. Therefore, it becomes necessary to consider differences among citrus growers in each region and setting out the most appropriatestrategies for vector and disease management. Highlights Some operational practices that citrus growers are not aware of may influence their perception of chemical control. The sociocultural context of growers determines their decision-taking on insecticide applications. During the application of insecticides in regional control areas (RCAs), growers do not take into account weather conditions. The effective management of D. citri requires a coordinated engagement of small growers' in RCAs

    ¿Quiénes son los estudiantes que abandonan los estudios? Identificación de factores personales y familiares asociados al abandono escolar en estudiantes de educación media superior

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    Datos publicados por la Secretaría de Educación Pública denotan que uno de los mayores problemas que enfrenta el Sistema Educativo Nacional es la baja retención de los estudiantes de educación media superior. El propósito de este estudio fue identificar a los alumnos en riesgo de desertar. El estudio identifica las variables que impactan el abandono escolar en tres momentos posteriores a la presentación del examen de admisión.A partir de esta conceptualización se generaron diferentes grupos de análisis: 1) sustentantes que aprobaron un examen de admisión y fueron asignados a un plantel (población base); 2) sustentantes que no se inscribieron al primer semestre; 3) alumnos que no terminaron el primer semestre; alumnos que no terminaron el segundo semestre; 4) alumnos que no terminaron el tercer semestre; 5) alumnos que no terminaron el cuarto semestre; y 6) el grupo de alumnos inscritos desertores. El estudio presenta un perfil descriptivo de cada uno de los grupos, en el que se identifican variables personales, familiares y de rendimiento académico. Adicionalmente se realizó un análisis de supervivencia no paramétrico, que contempló dos etapas de abandono: abandono-preinscripción; y abandono-inter-semestre. Los resultados presentan evidencia que los alumnos en riesgo de desertar presentaron bajos puntajes en el examen de ingreso, presentaron exámenes extraordinarios en el ciclo antecedente, reportaron llevar a cabo lecturas de esparcimiento por más de tres horas y que los que sus expectativas académicas eran alcanzar un posgrado fueron los que no se inscribieron y los que aspiraron sólo a bachillerato fueron los que no terminaron segundo semestre.Asimismo, los datos analizados indican que los hombres tienen mayor probabilidad de desertar en cada punto de análisis

    Isolating the Effects of Word’s Emotional Valence on Subsequent Morphosyntactic Processing: An Event-Related Brain Potentials Study

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    Emotional information significantly affects cognitive processes, as proved by research in the past decades. Recently, emotional effects on language comprehension and, particularly, syntactic processing, have been reported. However, more research is needed, as this is yet very scarce. The present paper focuses on the effects of emotion-laden linguistic material (words) on subsequent morphosyntactic processing, by using Event-Related brain Potentials (ERP). The main aim of this paper is to clarify whether the effects previously reported remain when positive, negative and neutral stimuli are equated in arousal levels and whether they remain long-lasting. In addition, we aimed at testing whether these effects vary as a function of the task performed with the emotion-laden words, to assess their robustness across variations in attention and cognitive load during the processing of the emotional words. In this regard, two different tasks were performed: a reading aloud (RA) task, where participants simply read aloud the words, written in black on white background, and an Emotional Stroop (ES) task, where participants named the colors in which the emotional words were shown. After these words, neutral sentences followed, that had to be evaluated for grammaticality while recording ERPs (50% containing a morphosyntactic anomaly). ERP analyses showed main effects of valence across tasks on the two components reflecting morphosyntactic processing: The Left Anterior Negativity (LAN) is increased by previous emotional words (more by negative than positive) relative to neutral ones, while the P600 is similarly decreased. No interactions between task and valence were found. As a result, an emotion-laden word preceding a sentence can modulate the syntactic processing of the latter, independently of the arousal and processing conditions of the emotional word

    Strontium and oxygen isotopes to trace mobility routes during the Bell Beaker period in the north of Spain

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    [EN]Strontium and oxygen isotopes of individuals from El Hundido and Valdescusa (north of Spain) sites, corresponding to the Bell Beaker culture, were analysed in order to determine mobility patterns and provenance areas. Strontium and oxygen isotope ratios in three teeth from two individuals at El Hundido and two teeth from the five individuals at Valdescusa were studied. The analyses were performed in both dentine and enamel fractions. Sr-87/Sr-86 ratios of El Hundido individuals indicate one was of foreign origin and the other was local whereas at Valdescusa were all of foreign provenance. Calculated delta O-18(w) values of El Hundido suggest a provenance from the geographical area close to the site while the Valdescusa would come from a warmer region. The comparison of oxygen and strontium isotope signatures indicate the west of the Iberian Peninsula (Zamora or the east of Leon regions) as the provenance area for the foreign individual at El Hundido and southwest France (Garonne basin) as the region of provenance for the Valdescusa.This work has been supported financially by Research Group IT1193-19 and PIBA 2018_1_0053 research projects of the Government of the Basque Country

    The Automatic but Flexible and Content-Dependent Nature of Syntax

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    Syntactic processing has often been considered an utmost example of unconscious automatic processing. In this line, it has been demonstrated that masked words containing syntactic anomalies are processed by our brain triggering event related potential (ERP) components similar to the ones triggered by conscious syntactic anomalies, thus supporting the automatic nature of the syntactic processing. Conversely, recent evidence also points out that regardless of the level of awareness, emotional information and other relevant extralinguistic information modulate conscious syntactic processing too. These results are also in line with suggestions that, under certain circumstances, syntactic processing could also be flexible and context-dependent. However, the study of the concomitant automatic but flexible conception of syntactic parsing is very scarce. Hence, to this aim, we examined whether and how masked emotional words (positive, negative, and neutral masked adjectives) containing morphosyntactic anomalies (half of the cases) affect linguistic comprehension of an ongoing unmasked sentence that also can contain a number agreement anomaly between the noun and the verb. ERP components were observed to emotional information (EPN), masked anomalies (LAN and a weak P600), and unmasked ones (LAN/N400 and P600). Furthermore, interactions in the processing of conscious and unconscious morphosyntactic anomalies and between unconscious emotional information and conscious anomalies were detected. The findings support, on the one hand, the automatic nature of syntax, given that syntactic components LAN and P600 were observed to unconscious anomalies. On the other hand, the flexible, permeable, and context-dependent nature of the syntactic processing is also supported, since unconscious information modulated conscious syntactic components. This double nature of syntactic processing is in line with theories of automaticity, suggesting that even unconscious/automatic, syntactic processing is flexible, adaptable, and context-dependent

    Peripheral myeloid cells infiltrate the hippocampus of Alzheimer's disease patients.

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    Microglia, the brain-resident myeloid cells, play a major role in the immune responses of the nervous system and in the pathogenesis of Alzheimer's disease (AD). However, the presence of peripheral myeloid cells in the AD brains remain to be demonstrated. Cellular and molecular approaches have been carried out in post-mortem hippocampal samples from patients with AD and age-matched controls without neurological symptoms. Our study provides evidence that circulating monocytes infiltrate the AD brains. Our findings showed that a high proportion of demented cases was associated with up-regulation of genes rarely expressed by microglial cells and abundant in monocytes-derived cells (MDC), among which stands the scavenger receptor Cd163. These Cd163-positive MDC invaded the brain parenchyma, acquired a microglial-like morphology, and were located in close proximity to blood vessels. These cells infiltrated the nearby amyloid plaques contributing to plaque-associated myeloid cell heterogeneity. Besides, control individuals with high amyloid pathology, showed no signs of MDC brain infiltration or plaque invasion. The MDC infiltration was associated with the progression and severity of AD pathology.These results reveal the co-existence of distinct myeloid populations associated with amyloid plaques during disease progression, as well their region-specific contribution to neuroimmune protection. The recruitment of monocytes could be a consequence rather than the cause of the severity of the disease. Whether monocyte infiltration is beneficial or detrimental to AD pathology remains to be fully elucidated. These findings open the opportunity to design targeted therapies, not only to microglia, but also to peripheral immune cell population to modulate amyloid pathology and provide a better understanding of the immunological mechanisms underlying AD progression.Supported by ISCiii grants(PI21-0915(AG),PI21-00914(JV)co-financed by FEDER funds from European Union;Junta de Andalucia grants P18-RT-2233(AG) and US-1262734(JV)co-financed by Programa Operativo FEDER 2014-2020;PPIT.UMA.B1-2019-07(ESM). Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Stress-related coping styles, anxiety, and neuroticism in university students with myalgia temporomandibular: A case control study

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    Los pacientes que sufren dolor debido a trastornos temporomandibulares (TTM) presentan mayores niveles de distrés psicológico, estrés ambiental, síntomas somáticos, ansiedad, depresion, cogniciones de catastrofización, y otras estrategias de afrontamiento al dolor alteradas, comparados con personas libres de dolor. Sin embargo, poco se conoce acerca de los factores psicológicos involucrados en diferentes tipos de TTM. Además, independientemente de la gravedad o el tipo de TTM, el papel de los estilos y estrategias de afrontamiento al estrés en los TTM todavía no está claro. El principal objetivo de este trabajo es estudiar los estilos de afrontamiento al estrés, ansiedad y rasgos de personalidad en un grupo de estudiantes de odontología que sufren mialgia temporomandibular. Una muestra de 102 estudiantes universitarios fue inicialmente reclutada para este estudio. Tras una evaluación clínica, se formaron un grupo de estudiantes con mialgia (24 participantes) y un grupo de estudiantes control (24 participantes). Los participantes de ambos grupos fueron posteriormente evaluados en ansiedad, estrategias de afrontamiento al estrés, y rasgos de personalidad. El grupo con mialgia mostró mayor rasgo de ansiedad y neuroticismo que el grupo control. Los participantes con mialgia también mostraron un mayor uso de estrategias de afrontamiento evitativas. Las estrategias evitativas generalmente se han considerado como desadaptativas, y se ha visto que incrementan el estrés percibido, un fuerte predictor de TTM.Patients suffering pain-related temporomandibular disorders (TMD) exhibit greater levels of psychological distress, environmental stress, somatic symptoms, anxiety, depression, pain catastrophizing, and impaired pain coping strategies compared to pain-free controls. However, little is known about psychological factors involved in the different TMD types. Furthermore, regardless of severity or TMD type, the role of stress-related coping strategies and styles in TMD is not yet well understood. The main goal of this study was to investigate stress-related coping styles, anxiety, and personality traits in a group of dentistry students suffering from temporomandibular disorder with myalgia. A cohort of 102 university students was initially recruited for this study. Following clinical evaluation, a myalgia group (24 participants) and a control group (25 participants) were formed. Participants were later assessed in anxiety, stress coping strategies, and personality measures. The myalgia group presented greater levels of trait anxiety and neuroticism in comparison to the control group. Participants with myalgia also showed higher levels of avoidance coping. Avoidance coping strategies are generally considered maladaptive, as they seem to increase perceived stress, a robust predictor of TM

    La teoría del valor-trabajo a través de las principales escuelas económicas: un enfoque documental

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    Este trabajo hace una exposición, basada en una recopilación documental, sobre la visión de la teoría del valor-trabajo de los autores más representativos de las diferentes escuelas de pensamiento económico desde el siglo XVII con William Petty, pasando por Adam Smith, David Ricardo, Karl Marx, Alfred Marshall, John Keynes, entre otros; esto con la finalidad de determinar la transformación que ha tenido este concepto a través de estos y su evolución histórica. Finalmente, este trabajo concluye que la generalidad de los autores no reconoce una importancia estratégica o mayoritaria al trabajo como único elemento del valor; en cambio, se observa una ponderación entre varios elementos y categorías conceptuales. Adicionalmente, se establece a Marx como punto cúspide de la teoría, y, además, como punto de inflexión en donde la teoría del valor abandona paulatinamente la importancia estratégica del trabajo

    Metales Pesados (Ba, Cu y Hg) en tejidos de Mugil curema (Valenciennes, 1836) de la laguna de Tampamachoco, Veracruz, México

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    A nivel mundial, las lagunas costeras son consideradas como ambientes de alta productividad y una elevada riqueza en biodiversidad. Están situadas a lo largo del litoral que en la mayoría de los casos tienen una comunidad permanente con el mar como es el caso de la laguna de Tampamachoco, Veracruz. Biológicamente, la zona costera y marina del Golfo de México representa una región de gran valor ecológico y económico para México ya que tiene una gran diversidad de ecosistemas marinos y recursos naturales. Los metales pesados son elementos naturales de la corteza terrestre, rocas, suelos, sedimentos, erupciones volcánicas y del agua. Existen cambios en sus concentraciones debido al uso extensivo en la industria y actividades humanas. Este estudio tuvo como objetivo el determinar si se encuentran presentes los metales pesados Ba, Cu y Hg en organismos de lebrancha (Mugil curema Valenciennes, 1836). Se muestrearon peces para el análisis cuantitativo de los metales pesados. El método que se utilizó se hizo en base a la Norma Oficial Mexicana NOM-117-SSA1-1994 mediante la técnica “Espectrometría de absorción atómica”. Se hicieron 14 muestreos del 2009 al 2010. La concentración promedio en tejidos para el músculo fue de Ba= 9.66 mg/kg, Cu= 3.33 mg/kg; en piel fue de Ba= 14.40 mg/kg, Cu= 6.28 mg/kg; en branquias fue de Ba= 43.26 mg/kg, Cu= 8.13 mg/kg; y finalmente en hígado fue de Ba= 7.57 mg/kg, Cu= 25.99 mg/kg. Las concentraciones que se hallaron en los tejidos de M. curema principalmente en las branquias son el tejido principal de recolección de los metales pesados, ya que la respiración es un factor determinante en la bioacumulación de estos contaminantes

    Immediate Loading of Implants with Fixed Rehabilitations in Geriatric Edentulous Patients; Biological Complications

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    Background: This study aimed to report the outcomes of the immediate loading of implants with fixed rehabilitations in edentulous geriatric patients. Methods: Edentulous geriatric patients were diagnosed with an oral examination, radiographic evaluation, and intermaxillary relations and treated with fixed rehabilitation over several implants. After immediate surgery, the implants were immediately loaded with a fully fixed prosthesis. Results: Twenty-four patients (20 females and 4 males) were treated using a total 210 implants. All patients (100%) had a previous history of periodontitis. Eleven patients (45.8%) were smokers. Eleven patients (45.8%) suffered from chronic medical diseases (i.e., diabetes, cardiovascular diseases). The study's clinical follow-up period extended for three years, during which thirty-three fixed prostheses were installed over the implants in 24 patients. The average marginal bone loss measured was 1.33 +/- 0.17 mm. The success rate of the implants and prosthodontics being placed in this study yielded 98.5% and 97%, respectively. One patient (4.2%) showed some kind of technical complications. Eleven patients (45.8%) showed mucositis, and 25 implants (11.9%) in 10 patients (41.7%) were associated with peri-implantitis. Conclusions: This study shows that the treatment of edentulous geriatric patients by immediate loading of implants with fixed rehabilitations is a clinically successful protocol but with a high prevalence of peri-implant diseases
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