Resumen Este artículo de investigación presenta una reflexión en clave pedagógica sobre la crisis del concepto de disciplina en la escuela contemporánea, alineada cada vez más a un régimen liberal a causa del fenómeno de des-institucionalización por el que atraviesa en la actualidad. En ese orden de ideas, el texto comienza con la descripción de la categoría disciplina, revelando el peso de esta en la constitución de lo humano; luego, caracteriza su declive en lo escolar como consecuencia del desfondamiento que hoy sufren las instituciones en el marco de las sociedades de seguridad y, finalmente, termina presentando los efectos de la era de lo securitario en la educación y la pedagogía, con sus subsecuentes repercusiones en la enseñanza.

Abstract This research article presents a pedagogical reflection on the crisis of the concept of discipline in the contemporary school, increasingly aligned with a liberal regime due to of the phenomenon of deinstitutionalization that it is currently experiencing. In this order of ideas, the text begins with the description of the discipline category, revealing its weight in the constitution of the human; then, it characterizes its decline in school as a result of the setbacks that institutions suffer today within the framework of security societies and, finally, ends by presenting the effects of the era of the security in education and pedagogy, with its subsequent repercussions in education.

Resumo Este artigo de pesquisa apresenta uma reflexão pedagógica sobre a crise do conceito de disciplina na escola contemporânea, cada vez mais alinhada com um regime liberal, devido ao fenômeno da desinstitucionalização que está vivenciando atualmente. Nessa ordem de ideias, o texto começa com a descrição da categoria disciplina, revelando seu peso na constituição do humano; depois, caracteriza seu declínio na escola como resultado da quebra que as instituições sofrem hoje no âmbito das sociedades de segurança e, finalmente, finda apresentando os efeitos da era da segurança na educação e na pedagogia, com suas consequentes repercussões na educação.

Maize is the most important grain crop in Mexico due to the largest area grown and as the main source of feeding nationwide; being Sinaloa de major producer. The same crop over repeated seasons has favored disease proliferation of stem and ear rot mainly attributed to Fusarium spp which represents a risk potential so that growers are warned top pay close attention to crop management. With the purpose of evaluating the effect of synthetic fertilization with compost and irrigation on maize stem and ear rot at Valle del Fuerte. Field experiments were conducted in the growing season of 2009 at INIFAP. The experiments were arranged under a split plot in randomized complete block design with three replicates. At the end of the season, it was found that fertilization or irrigation by themselves did not have any significant effect in yield and phenology variables evaluated. However, incidence on stem rot which was evaluated at 53 days after planting was that of 100%. Moreover, there were significant differences regarding severity of rotten ears when less irrigation was applied. Finally, morphological study showed that the main agent associated in maize stem rot was Fusarium verticilliodes. In contrast to that of ear rot that the main agents involved were Apergillus spp, Penicillum pinophilum, and with a higher incidence was Fusarium verticilliodes.

El maíz es el cultivo agrícola de grano más importante de México por ser sembrado con mayor superficie y ser la base de la alimentación en toda la nación siendo Sinaloa el principal productor. La siembra repetitiva del cultivo efectuada a través de los años, ha favorecido la proliferación de enfermedades como la pudrición de tallos y la pudrición de mazorcas, atribuidas principalmente a Fusarium spp, las cuales representan un potencial de riesgo y han alertado al productor a poner mucha atención en el manejo del cultivo. Con el objetivo de evaluar el efecto de la fertilización sintética con composta y riego sobre la pudrición de tallos y mazorcas de maíz en el Valle del Fuerte; experimentos de campo se condujeron en el ciclo agrícola primavera-verano 2009 en el INIFAP. El experimento fue diseñado en parcelas divididas en bloques completos al azar con tres repeticiones; al final del ciclo se encontró que no hubo diferencias significativas del factor fertilización y riego respecto al rendimiento así como las variables fenológicas evaluadas. La incidencia de pudrición de tallos evaluada a los 53 días después de la siembra fue de 100%. Sin embargo, se encontraron diferencias significativas en cuanto a la severidad de mazorcas podridas donde se aplicaron menos riegos. Finalmente, el estudio morfológico mostro que el principal agente asociado en pudrición de tallos fue Fusarium verticilliodes y en cuanto a pudrición de mazorcas se detectó una mayor diversidad de agentes asociados tales como Apergillus spp, Penicillum pinophilum, y con mayor incidencia Fusarium verticilliodes.

Phosphate-solubilising saprophytic fungi have a potential application in plant nutrition; therefore, the aim of this study was 1) to perform a screening and isolation of native phosphofungi from volcanic soils of southern Chile, 2) to select a liquid medium for the evaluation of these phosphofungi and 3) to test a selected phospho fungus as a biofertiliser in a volcanic soil. The phosphofungi were screened using Martin medium (rose bengal-streptomycin agar) with calcium phosphate (Ca3(PO4)2) or calcium phytate as the phosphorus source. Six promising strains (Penicillium sp., Penicillium albidum, Penicillium thomii, Penicillium restrictum, Penicillium frequentans and Gliocladium roseum) were evaluated in the liquid media of Agnihotri, Asea-Wakelin, Pikovskaya and Nahas. The soluble phosphorus, acid phosphatase activity, pH and fungal biomass were determined. In most soils, the greatest proportion of phosphofungi solubilised organic P. The Asea-Wakelin medium appears to be the medium of choice for the quantitative evaluation of phosphofungi isolated from the volcanic soils tested. Penicillium albidum was selected as a potential biofertiliser due to its capacity to solubilise both inorganic and organic P via its specific solubilising activity (64 mg P/g fungus), phosphatase secretion and enhancement of the growth and mineral nutrition of lettuce plants growing in a volcanic soil.

The presence of the bronze bug Thaumastocoris peregrinus was first reported in the country in June 2009, as a result of the Forest Surveillance Program of Servicio Agrícola y Ganadero (SAG). Sucking insects which cause damage as nymphs and adults feeding of sap on the leaves of their hosts. When populations increase, there is a sharp reduction in leaf photosynthetic rate, which can cause decreased growth and sometimes result in complete defoliation of the tree. The aims of this study were to confirm the detection of T. peregrinus, define its range and set the host range within the genus Eucalyptus species present in Chile. Thus, sticky yellow traps were installed in the metropolitan region, municipality of Til-Til, and in the region of Valparaíso; furthermore, national surveys were conducted covering the regions where species of Eucalyptus are grown. Nine positives (= presence) were detected in the metropolitan area and one in the region of Valparaíso. The detection of immature and adult T. peregrinus on Eucalyptus camaldulensis indicates that the insect is established in the region. We present actions to be carried out within the official control tasks performed by SAG.

La presencia del chinche del eucalipto, Thaumastocoris peregrinus, fue reportada por primera vez en el país en junio de 2009, como resultado del Programa de Vigilancia Forestal del Servicio Agrícola y Ganadero (SAG). Insecto succionador cuyo daño lo ocasionan tanto ninfas como adultos al alimentarse de la savia de sus hospederos desde las hojas. Cuando las poblaciones aumentan, se produce una fuerte reducción de la tasa fotosintética de las hojas, lo que puede provocar una disminución del crecimiento y en ocasiones producir la defoliación completa del árbol. Los objetivos de este estudio fueron constatar la detección de T. peregrinus, delimitar su área de distribución y establecer el rango de hospederos dentro de las especies del género Eucalyptus presentes en Chile. Para esto se instalaron trampas amarillas pegajosas en la región Metropolitana, comuna de Til-Til, y en la región de Valparaíso y se realizó una prospección nacional que abarcó las regiones con presencia de especies del género Eucalyptus. Se detectaron nueve puntos positivos (= presencia) en la región Metropolitana y uno en la región de Valparaíso. La detección de estados inmaduros y adultos de T. peregrinus sobre E. camaldulensis indica que el insecto se encuentra establecido en las regiones Metropolitana y de Valparaíso, Chile. Se dan a conocer las acciones a seguir dentro de las labores de control oficial ejecutadas por el SAG.

Metallic nanoparticles of Au, Pt and Pt/Au have been synthesized using a chemical reduction approach. The structural characterization of these metallic nanoparticles has been carried out using conventional transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HR-TEM) techniques. HR-TEM images of Pt nanoparticles reveal their fcc-like structures, in the [103] and [011] orientations. However, in case of Au, the main structures are fcc-like and decahedral morphologies with five-fold symmetry axes. The structure of the gold nanoparticles was verified through their theoretically-simulated images, using a multislice approach of the dynamical theory of electron diffraction. These small particles have been used as electrocatalysts in Nafion membranes for fuel cell applications. The electrochemical characterization of the membranes shows that the Pt dispersion gives best performance for fuel cell applications.

Background: Many patients with irritable bowel syndrome (IBS) have lowered sensory thresholds to rectal distention when compared to control subjects, a phenomenon called visceral hypersensitivity. Aim: To investigate the usefulness of a rectal barostat as a diagnostic tool in IBS and if there are differences in visceral hypersensitivity in different groups of IBS patients. Patients and Methods: Ten healthy subjects and 19 IBS patients, defined using Rome II criteria (12 with constipation, three with diarrhea and four alternating between diarrhea and constipation), were studied. Sequential isobaric rectal distentions, from 2 mmHg up to a maximal pressure of 52 mmHg or when the patients reported pain, were carried out. Visceral hypersensitivity was defined as a pain threshold under 38 mmHg. Results: Only 26% of IBS patients had visceral hypersensitivity (16% and 43% of patients with IBS and constipation and IBS and diarrhea or alternating symptoms, respectively, p =NS). Pain threshold in controls, patients with IBS and constipation and patients with IBS and diarrhea or alternating symptoms was 43.8±6.6, 45.3±9.2 and 40.8±9.2 mmHg, respectively (p =NS). Conclusions: Our results do not support the usefulness of the electronic rectal barostat as a diagnostic method to diagnose IBS

The prevalence of celiac disease (CD) is unknown in Chile. We have recently noted a rise in the number of cases diagnosed among adults. Aim: To describe the clinical characteristics of a group of adult celiac patients. Patients and methods: Clinical data of patients older than 15 years with positive antitransglutaminase or antiendomysial autoantibodies and a duodenal biopsy characteristic of CD were retrospectively reviewed. Age at diagnosis, symptoms and signs and laboratory, endoscopic and histological findings, were analyzed. Results: Thirty seven patients (28 women), were studied. Median age at diagnosis was 41 years (range 15-69). Main symptoms and signs were diarrhea (78%), weight loss (38%) and abdominal pain (38%). Anemia was found in 49%, elevation of ESR in 57%, elevation of alkaline phosphatases in 54%, elevation of aspartate aminotransferase in 38% and a rise in alanine aminotransferase in 27%. Antiendomysial antibodies were positive in 17/22 (77%) and antitransglutaminase in 19/22 (86%) patients. Endoscopic findings were suggestive of CD in 47% of cases and duodenal biopsy showed intestinal villi atrophy in 34 (92%) patients. The three patients with normal histology had positive serology and a good response to gluten free diet. Conclusions: CD should be considered in the differential diagnosis of patients with unespecific digestive symptons, even when they present late in adult life. Serologic markers are a good diagnostic tool. A normal duodenal pathology does not exclude the diagnosis, if other diagnostic features are present

The incidence of Inflammatory Bowel Disease (IBD) has increased, particularly in the developed world, and probably also in Chile. Aim: To report our experience with a large group of patients from two medical centers, Hospital Clinico de la Universidad de Chile (HCUCH) and Clinica Las Condes (CLC) and to characterize the clinical features of IBD in Chile. Patients and methods: Retrospective review of 238 patients with IBD (age range 14-78 years, 143 women) treated at HCUCH and CLC between January 1990 and August 2002. Results: One hundred eighty one patients had ulcerative colitis (UC) and 57 had Crohn's disease (CD), with an UC/CD ratio of 3.2/1. Forty eight percent of patients were aged between 20 and 39 years old and 69% were diagnosed after 1995. Patients from HCUCH had more severe disease, more complications and needed surgery more often. Conclusions: Clinical features of Chilean patients with IBD are similar to those of other countries. UC is more common than EC. There is a higher proportion of women with the disease. The severity of the disease was higher among HCUCH

Twenty years ago Helicobacter pylori was identified in the gastric content and this finding stimulated a multitude of studies and publications that changed drastically our knowledge of common gastric conditions such as peptic ulcer and gastric cancer. This progress has affected significantly our practice and has resulted in great benefits for our patients. The relationship of the bacteria to the pathogenesis of gastritis, peptic ulcer, gastric cancer and gastric lymphoma was firmly established. A large number of individuals are infected (an estimated half of the world's population) while only a minority suffers of the above mentioned conditions, so it became clear that certain strains of the bacteria, susceptibility of the host and environmental factors interplay in causing the damage. The diagnosis of the infection became a standard practice and therapy and prevention of these common conditions has been drastically modified. Eradication of the bacteria resulted in the cure of ulcers, in a dramatic decrease in the rate of its complications and in the ocurrence of gastric cancer. Better sanitary conditions are part of the solution. Also it is successful in the management of certain gastric lymphomas. The treatment however, is expensive and not free of side effects. Further research work is needed to facilitate the diagnosis and less expensive treatments should be available to eradicate Helicobacter pylori throughout the world

Despite significant advances in the recognition of etiological factors and pathological mechanisms, the pathophysiology of functional gastrointestinal disorders (FGD) is still not fully understood. Visceral hypersensitivity has been recognized as a characteristic of patients with FGD, especially in patients with irritable bowel syndrome (IBS). Visceral afferent input is modulated by a variety of mechanisms, operating between the gastrointestinal tract and the brain. Dysfunction of these regulatory mechanisms could distort gastrointestinal perceptions. Recent findings suggest that in the majority of cases of IBS the primary abnormality may be at the periphery with alterations of the motor and secretory sensory activity. Although imaging techniques indicate that there are also differences in cortical activation. Furthermore, selective serotonin reuptake inhibitors may benefit FGD. Recent pharmacological studies suggest that 5-HT3 antagonist such as alosetron and cilansetron, and 5-HT4 agonist such as tegaserod and prucalopride may also have a potential use in FGD (Rev Méd Chile 2003; 131: 85-92)

We report the structure of a new phenolic compound from S. stipulaceae, which has been identified as the dimer 5-(3-formyl-4-hydroxyfenoxy)-2-hydroxybenzaldehyde , together with five known compounds; also is evaluated the antifeedant activity of stems and leaves extracts in choice and no-choice assays

De Senna stipulacea se aisló un nuevo compuesto fenólico identificado como el dímero 5-(3-formil-4-hidroxifenoxi)-2-hidroxibenzaldehído, junto a 5 compuestos conocidos; y se evaluó la actividad antialimentaria de extractos de tallos y hojas en ensayos de elección y no elección