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Effectiveness of in-group versus individually administered pain neuroscience education on clinical and psychosocial outcomes in patients with chronic low back pain: randomized controlled study protocol
No full textObjective . (1) This trial will compare the clinical and psychosocial effectiveness of in-group and individually pain neuroscience education (PNE) in patients with chronic low back pain (CLBP). In addition, (2) the influence of social determinants of health on post -treatment results will be analyzed. Methods . A three -arm randomized controlled trial will be conducted. Sixty-nine participants with CLBP will be recruited in a 1:1:1 ratio. Participants, assessor, and statistician will be blinded to group assignment. The PNE intervention will be adapted to the context of the participants. An experimental group ( n = 33) will receive PNE in an in-group modality, the other experimental group ( n = 33) will receive PNE in an individually modality and the control group ( n = 33) will continue with usual care. Additionally, participants will be encouraged to stay active by walking for 20- 30 min 3-5 times per week and will be taught an exercise to improve transversus abdominis activation (bracing or abdominal following). The outcome measures will be fear avoidance and beliefs, pressure pain threshold, pain self -efficacy, catastrophizing, pain intensity, and treatment expectation. Outcome measures will be collected at one -week before intervention, immediately post -intervention, and four -weeks postintervention. Conclusion . The innovative approach of PNE oriented to fear beliefs proposed in this study could broaden the application strategies of this educational therapeutic modality. Impact. Contextualized PNE delivered by physical therapist could be essential to achieve a good cost-effectiveness ratio of this intervention to improve the clinical condition of people with CLBP
Bulk serum extracellular vesicles from stressed mice show a distinct proteome and induce behavioral and molecular changes in naive mice
No full textChronic stress can trigger several pathologies including mood disorders for which no clear diagnostic molecular markers have been established yet. Attractive biomarker sources are extracellular vesicles (EVs). Evs are released by cells in health and disease and contain genetic material, proteins and lipids characteristic of the cell state. Here we show that Evs recovered from the blood of animals exposed to a repeated interrupted stress protocol (RIS) have a different protein profile compared to those obtained from control animals. Proteomic analysis indicated that proteins differentially present in bulk serum Evs from stressed animals were implicated in metabolic and inflammatory pathways and several of them were previously related to psychiatric disorders. Interestingly, these serum Evs carry brain-enriched proteins including the stress-responsive neuronal protein M6a. Then, we used an in-utero electroporation strategy to selectively overexpress M6a-GFP in brain neurons and found that M6a-GFP could also be detected in bulk serum Evs suggesting a neuronal origin. Finally, to determine if these Evs could have functional consequences, we administered Evs from control and RIS animals intranasally to na & iuml;ve mice. Animals receiving stress EVs showed changes in behavior and brain M6a levels similar to those observed in physically stressed animals. Such changes could therefore be attributed, or at least in part, to EV protein transfer. Altogether these findings show that EVs may participate in stress signaling and propose proteins carried by EVs as a valuable source of biomarkers for stress-induced diseases
Determining the optimum percentages of fly ash, metakaolin and copper slag by replacing cement and fine aggregate in m30 grade concrete
Get PDFThe overall production of the cement has greatly increased which results lots of problems in environment as it involves the emission of CO2 gas. Environmental concerns, stemming from the high energy expense and carbon dioxide emission associated with cement manufacture have brought about pressures to reduce cement consumption through the use of supplementary materials. Materials such as Metakaolin, fly ash have good pozzolanic activity and are a good material for the production of high strength concrete. Copper slag is a by-product of copper extraction by smelting. Copper slag can be used in concrete production as a partial replacement for sand. However,it is expected that the use of Metakaolin, Fly ash and Copper slag in concrete improves the strength properties of concrete.La producción general de cemento ha aumentado considerablemente, lo que genera muchos problemas en el medio ambiente, ya que implica la emisión de gas CO2. Las preocupaciones ambientales, derivadas del alto gasto energético y la emisión de dióxido de carbono asociados con la fabricación de cemento, han generado presiones para reducir el consumo de cemento mediante el uso de materiales complementarios. Materiales como el metacaolín, las cenizas volantes tienen una buena actividad puzolánica y son un buen material para la producción de hormigón de alta resistencia. La escoria de cobre es un subproducto de la extracción de cobre por fundición. La escoria de cobre se puede utilizar en la producción de hormigón como reemplazo parcial de la arena. Sin embargo, se espera que el uso de metacaolín, cenizas volantes y escoria de cobre en el hormigón mejore las propiedades de resistencia del hormigón
A review of zooplankton research in Chile
No full textThis study is a review of literature records on diversity, distribution and ecology of the Chilean inland water zooplankton including microcrustaceans (Copepoda, Branchiopoda), rotifera (Bdelloida and Monogononta) and ciliated protozoa. For that, several databases were consulted, and about 239 records were analysed and evaluated. The results revealed that in total about 109 water bodies have been sampled in Chile. Crustacea are well studied in the entire Chilean territory, whereas records on Rotifera and Ciliata are more restricted to the Central and Southern zones. Within Crustacea calanoid copepods of the genus Boeckella and to lower degree Cladocera (Branchiopoda) predominate. Anostraca are reported for hypersaline waterbodies and ephemeral pools, whereas Laevicaudata and Spinicaudata (Branchiopoda) are only found in shallow ephemeral pools. Regarding rotifers, 121 species were identified, whereas 46 species of ciliated protozoa were registered in lentic water bodies of the Southern zone. Ecological studies included different aspects as population dynamics, vertical migration, diapause, role of ultraviolet radiation among others. We discuss also shortcomings and future studies. Future studies should consider more in detail population dynamics, molecular topics to better assess taxonomical determinations, trophic interactions within the food webs and effects of global changes at population and community level
Characterization of alginate from Antarctic Himantothallus grandifolius (Phaeophyceae) and preparation of polyelectrolyte complexes with chitosan
No full textHydrogels are three-dimensional polymeric materials with applications in various areas such as biomedicine, tissue engineering, pollutant capture systems, and so forth. However, its application is limited due to the reproducibility of its properties. Factors such as the composition of the constituents, the type of union between the polymer chains, and the crosslinking time play a crucial role in ensuring its reproducibility. In this study, the objective is to prepare a matrix with well-defined properties that ensure controlled release processes. Treatment of Himantothallus grandifolius with Na2CO3 aqueous solution afforded in 18.9% yield alkaline extract. Hydrogels were prepared by ionic complexation of alginate from H. grandifolius, and polyguluronate enriched alginate from Desmarestia ligulata with chitosan stabilized by immersion in 0.1 M CaCl2 solution; better swelling ratio in water was found for hydrogels with low molecular weight chitosan (MW 125,000 g/mol) than those with medium molecular weight chitosan (MW450,000-500,000 g/mol). Liberation of the model drug metformin hydrochloride from alginates: chitosan complexes (3:1) at pH 1.5 was especially low for hydrogel from H. grandifolius during the first 2 h; 70% of metformin was released at pH 6.5 after 24 h. This polyelectrolyte complex constitutes a good material for potential application in biomedicine considering its cationic and anionic characteristics
Do you want to know a secret? Strategic alliances and competition in product markets
No full textStrategic alliances make firms' boundaries permeable to information leakages that may benefit the competitive position of partnering firms. In this paper, we examine the implications of information leakage on the incentives to join a strategic alliance and the nature of competition in the product market. We show that information leakage can trigger opportunistic behaviours in which firms engage in unprofitable alliances simply because the possibility of learning sensitive information about their competitors increases the expected private rents that firms earn when competing in the product market. Thus, our findings uncover a purely informational mechanism through which information leakage affects the incentives to join a strategic alliance that does not rely on the firm's ability to absorb spillovers from other firms. We also show that the incentives to devise alliances to gain access to the partner's sensitive private information may remain even if the negatively affected firm can pursue compensation for the damage that this deceptive business practice may cause
Beyond language: conceptualizing epistemic violence against Black immigrant students in mathematics education
No full textThis paper provides on-the-ground accounts of epistemic violence against Black immigrant children in mathematics classrooms. From a critical feminist perspective, we introduce Dotson's notion of silencing as an enactment of epistemic violence. According to Dotson, one way to enact epistemic violence is to damage a particular group's ability to speak and be heard. A successful act of communication depends on the audience's willingness and ability to 'hear' the speaker. Therefore, denying this reciprocity in communication is a form of epistemic violence. Using this conceptualization, we conducted a secondary data analysis from a larger study aimed at enhancing teachers' knowledge and abilities to implement problem-solving teaching. We identify and characterize three practices of silencing Black immigrant students in Chilean mathematics classrooms that damage their agency as knowers and doers of mathematics. Beyond language issues, we show that silencing is a form of anti-Black onto-epistemic violence that prevents Black immigrant students from being recognized as legitimate subjects of knowledge in mathematics classrooms
“Nuevos ciudadanos”: reconocimiento como justicia social para migrantes/"New citizens": recognition as social justice migrants
No full textLa migración es un tema que ha cobrado relevancia en la actualidad dado los altos índices de movilización humana y cruce de fronteras, especialmente frente a conflictos sociales del mundo, ejemplo de ello el fenómeno de migraciones sur- sur., es decir, entre países de América Latina. Actualmente las oleadas migratorias aumentan con los cambios sociales, políticos y, particular- mente, económicos del mundo. Chile no deja de ser receptor de estos grupos de personas, quienes deciden cambiar sus estatus sociales como inmigrantes incorporándose a nuevas culturas. Los flujos migratorios aumentan con la globalización provocando nuevas relaciones sociales en espacios y territorios culturalmente definidos, tal es caso del aumento y movilidad de la migración en la ciudad de Temuco. Como resultados de estas nuevas dinámicas se configuran procesos de ciudadanía especialmente en las formas cotidianas de participación e interacción de todos los habitantes, emergiendo de manera dinámica diferentes formas de acción e intervención en los migrantes en la región de la Araucanía. El preguntarse sobre la ciudadanía intercultural desde una perspectiva de la justicia permitirá generar acuerdos para el alcance real del uso pleno de la ciudadanía, trayendo consigo la aplicación de la justicia social y empoderamiento ciudadano para todos y todas
Resistance of Primary Photosynthesis to Photoinhibition in Antarctic Lichen <i>Xanthoria elegans</i>: Photoprotective Mechanisms Activated during a Short Period of High Light Stress
No full textThe Antarctic lichen, Xanthoria elegans, in its hydrated state has several physiological mechanisms to cope with high light effects on the photosynthetic processes of its photobionts. We aim to investigate the changes in primary photochemical processes of photosystem II in response to a short-term photoinhibitory treatment. Several chlorophyll a fluorescence techniques: (1) slow Kautsky kinetics supplemented with quenching mechanism analysis; (2) light response curves of photosynthetic electron transport (ETR); and (3) response curves of non-photochemical quenching (NPQ) were used in order to evaluate the phenomenon of photoinhibition of photosynthesis and its consequent recovery. Our findings suggest that X. elegans copes well with short-term high light (HL) stress due to effective photoprotective mechanisms that are activated during the photoinhibitory treatment. The investigations of quenching mechanisms revealed that photoinhibitory quenching (qIt) was a major non-photochemical quenching in HL-treated X. elegans; qIt relaxed rapidly and returned to pre-photoinhibition levels after a 120 min recovery. We conclude that the Antarctic lichen species X. elegans exhibits a high degree of photoinhibition resistance and effective non-photochemical quenching mechanisms. This photoprotective mechanism may help it survive even repeated periods of high light during the early austral summer season, when lichens are moist and physiologically active
Effectiveness of agricultural wastes in soil stabilization
Get PDFMany ways have been sought to improve soils, especially expansive soils which have been problematic to structures and pavements built over them and soil stabilization seems to be one of the effective ways. But soil stabilization in itself is not cost-effective hence the introduction of agricultural wastes being researched on and seen as a cheaper means to be used as stabilizing agents which helps in minimizing the cost of soil stabilization, thereby reducing the problem of waste disposal. Agricultural wastes like Rice Husk Ash, Bagasse Ash, Sugarcane Straw Ash, Saw Dust Ash, Coconut Husk Ash, Millet Husk Ash, Corn Cob Ash, Locust Bean Pod Ash, Cassava Peel Ash and Bamboo Leaf Ash have been experimented with in stabilizing soils and as well, serving as supplementary cementitious materials for cement in concrete production. The strengths of the soils and the concrete stabilized with these wastes were seen to improve significantly and their effectiveness was estimated based on an average optimum value. Agricultural waste processing Industries can be set up to help in the massive production of these natural stabilizers which would lessen the cost of soil stabilization using cement and chemicals and also generally reduce problems that are associated with waste disposal, helping in waste management.Se han buscado muchas formas de mejorar los suelos, especialmente los suelos expansivos que han sido problemáticos para las estructuras y pavimentos construidos sobre ellos, y la estabilización del suelo parece ser una de las formas efectivas. Pero la estabilización del suelo en sí misma no es rentable, por lo que la introducción de desechos agrícolas se está investigando y se considera un medio más barato para ser utilizado como agentes estabilizadores que ayuda a minimizar el costo de la estabilización del suelo, reduciendo así el problema de la eliminación de desechos. Residuos agrícolas como ceniza de cáscara de arroz, ceniza de bagazo, ceniza de paja de caña de azúcar, ceniza de polvo de sierra, ceniza de cáscara de coco, ceniza de cáscara de mijo, ceniza de mazorca de maíz, ceniza de vaina de algarrobo, ceniza de cáscara de yuca y ceniza de hoja de bambú se han experimentado con la estabilización de suelos y además, sirven como materiales cementantes suplementarios para el cemento en la producción de hormigón. Se observó una mejora significativa de las resistencias de los suelos y del hormigón estabilizado con estos residuos y se estimó su efectividad en base a un valor óptimo promedio. Se pueden establecer industrias de procesamiento de desechos agrícolas para ayudar en la producción masiva de estos estabilizadores naturales que reducirían el costo de la estabilización del suelo utilizando cemento y productos químicos y también reducirían en general los problemas asociados con la eliminación de desechos,lo que ayudaría en la gestión de desechos