vgaraujov/thesis-chile huggingface dataset:
The riboflavin-sensitized photooxidation of horseradish apoperoxidase

Native horseradish peroxidase, as well as its reduced and carboxymethylated form, and the apoenzyme, showed resistance to photodynamic action. Sensitivity to this action was detected only in reduced and carboxymethylated apoenzyme, when the photooxidation of its histidine residues was observed. When analyzing the bulk hydrophobic character (Hf) and the accessibility coefficients (Br) in those amino acid residues which can be subjected to photooxidation in horseradish peroxidase, it was found that all of them are situated in hydrophobic zones with low accessibility coefficients. This could justify the high resistance of this enzyme to photodynamic action. The only exception is tryptophan-117, which has low values of Hf and Br, and therefore its resistance to photodynamic action can only be explained in terms of its location and environment. Tryptophan-117 would be situated in a zone of antiparallel?-structure, according to Chou and Fasman's predictive method for protein conformation.
Fine structure of actinorhiza of theRhamnaceae growing in Chile I.Talguenea quinquenervia (Gill et Hook)

Root nodulesTalguenea quinquenervia Gill et Hook (Rhamnaceae) are restricted to the middle region of the root cortex. The root endophyte possesses hyphae which are septate and vesicles. The vesicles are spherical and are continuous with that of the hyphae. The endophyte fine structure is similar to otherFrankia-induced root nodules.
Vegetative responses to defoliation of two Chilean matorral shrubs

This paper reports the results of experimental defoliation of two common matorral species: Lithraea caustica and Colliguaya odorifera. L. caustica and C. odorifera are the matorral species previously shown to exhibit the highest and lowest levels of natural defoliation by browsing. Experimental defoliation was performed at four levels: 0% (controls), 25%, 66%, and 100%. C. odorifera exhibited vegetative responses stronger than controls only in the two highest levels of defoliation (66% and 100%), whereas L. caustica responded vigorously at the 25% and 100% levels. The results are related to the observed position of both species in the matorral community and their relative defoliation risks by natural and introduced herbivores.
Large cation-selective pores from rat liver peroxisomal membranes incorporated to planar lipid bilayers

Fusion of a highly purified fraction of rat liver peroxisomal membranes to planar lipid bilayers incorporates large, cation-selective voltage-dependent pores. ThePK/PCl ratio of these pores, estimated in KCl gradients, is close to 4. The pores display several conductance states and spend most of the time open at voltages near 0 mV, closing at more positive and negative voltages. At voltages near 0 mV the most frequent open state has a conductance of 2.4 nS in 0.3m KCl. At voltages more positive and more negative than 10 mV the most frequent open state displays a conductance of 1.2 nS in 0.3m KCl. With these results pore diameters of 3 and 1.5 nm, respectively, can be estimated. We suggest that these pores might account for the unusually high permeability of peroxisomes to low molecular weight solutes. Fusion also incorporates a perfectly anion-selective, two-open states channel with conductances of 50 and 100 pS in 0.1m KCl.
European rabbits versus native rodents in Central Chile: effects on shrub seedlings

The importance of the introduced rabbit Oryctolagus cuniculus and of the native rodent Octodon degus (=degu) as browsers of shrub seedlings in the Central Chilean evergreen shrublands (=matorral) was experimentally assessed. Seedlings were planted in several spatial arrangements in two open successional stands and in two mature stands of different cover and exposure. The browsing impact of rabbits and degus was evaluated separately after about one year since the start of the experiments. It was found that degus cause important seedling mortality only within a 5 m-radius centered at the border of their retreats. Rabbits, on the other hand, cause heavier seedling mortality, forage more widely, and consequently have a greater impact than do degus. It is speculated that rabbits may be halting the secondary succession process, shifting the matorral composition toward less palatable shrub species, and/or broadening the spacing between shrub clumps.
Rhodium(I) diolefin complexes with polycyclic π-arene ligands. Synthesis of bimetallic complexes with diphenylmethane as bridging ligand

The preparation and properties of cationic arenerhodium(I) complexes of general formula [Rh(diolefin)(?6arene)]ClO4 (diolefin=1,5-cyclooctadiene, tetrafluorobenzobarrelene or trimethyltetrafluorobenzobarrelene; arene = biphenyl or diphenylmethane) are described. These complexes react with the solvated intermediate complex [Rh(diolefin)(Me2CO)x]ClO4 to give homobimetallic [(diolefin)Rh(Ph2CH2)Rh(diolefin)](ClO4)2 derivatives. New heterobimetallic complexes of the type [(diolefin)Rh(Ph2CH2)Cr(CO)3]ClO4 have been synthesized by reaction of Cr(CO)3(?6-Ph2CH2) with the solvated complex [Rh(diolefin)(Me2CO)x]ClO4 or, alternatively by treatment of [Rh(diolefin)(?6-arene)]ClO4 with the complex Cr(CO)3(?6Me3B3N3Me3) in chloroform solution.
Study of a photo-induced lysozyme-riboflavin bond

Irradiation of lysozyme in the presence of riboflavin results in the formation of a lysozyme-riboflavin adduct. Reduction and carboxymethylation of the four disulfide bonds as well as the chemical modification of the Tyr residues and the photochemical alteration of the His residue in lysozyme, do not affect the formation of the photo-induced lysozyme-riboflavin bond. When the lysozyme-riboflavin adduct was subjected to mild acid hydrolysis and ion exchange chromatography, the retention of a compound containing14C-riboflavin was observed. Free14C-riboflavin, on the contrary is not retained by the column. The photo-oxidation of free Trp in the presence of14C-riboflavin, gave a compound which bound to the ion exchange resin like the above-mentioned derivative. The photo-oxidation of the Trp residues in lysozyme and in peptides obtained from lysozyme showed very high quantum yields, and these values were directly related to the incorporation of14C-riboflavin in these samples.
Amino terminal sequence of heavy and light chains from ratfish immunoglobulin

The ratfish,Callorhinchus callorhinchus, a representative of the Holocephali, has a natural serum hemagglutinin (Mr 960 000), composed of heavy (Mr 71000), light (Mr 22 500), and J (Mr 16 000) chains. To approach the mechanisms that generate diversity at this level of evolution, the amino terminal sequence of the heavy and light chains was determined by automated microsequencing. The chains are unblocked and have modest internal sequence heterogeneity. The heavy chains show sequence similarity with the terminal region of the heavy chain from the horned shark,Heterodontus francisci, and other species. In contrast to the heavy chain, the ratfish light chains display low sequence similarity with their shark kappa counterparts. However, their similarity with the variable region of the chicken lambda light chains is about 75%.
Functional and biochemical characteristics of a putative quisqualate-type receptor in rat striatum: Effect of brain lesions

Excitatory amino acids such asl-glutamate (Glu) and quisqualate (QUIS) markedly potentiated K+-evoked release of exogeneous [3H]dopamine (DA) from rat striatal slices. Intranstriatal kainic acid injections resulted in a total disappearance of the stimulatory effects of Glu on evoked-release of [3H]DA as well as in a parallel reduction in the maximal number (Bmax) of ad-aspartate-insensitivel-[3H]Glu binding site in striatal particulate fractions. Following cortical ablation, the potentiating effect of Glu on [3H]DA release in decorticated striatal slices lasted longer, compared to normal slices, and occured during the 2nd min following K+-depolarization. However, the extent (%) of Glu stimulation on [3H]DA release remained the same in decorticated and normal striatal slices. Cortical ablation produced also a significant decrease in the Bmax and in theK d' of thed-aspartateinsensitive binding site towardsl[3H]Glu. These results support the proposal that thed-aspartate-insensitive Glu binding site is somehow related to an amino acid receptor-mediated modulation of dopaminergic transmission in the rat corpus striatum.
Rhodium(I) complexes with pyridine-2-aldehyde and related Schiff-base ligands

The synthesis of [Rh(TFB)(PyCH=NR)]ClO4 by reaction of the coordinated pyridine-2-aldehyde (PyCHO) moiety of [Rh(TFB)(PyCHO)]ClO4 with primary amines is described. They are active catalysts for the transfer of hydrogen from isopropanol to acetophenone. The catalytic activity depends upon the basicity of the parent amine. Reactions with carbon monoxide and triphenylphosphine give complexes [Rh(CO)2(PyCH=NR)]ClO4, [Rh(CO)(PPh3)2(PyCH=NR)]ClO4 and [Rh(CO)(PPh3)(PyCH=NR)]ClO4.
Exposure of tryptophanyl residues inα-lactalbumin and lysozyme

The effect of iodide ion on the tryptophyl fluorescence of the homologous proteins lysozyme and?-lactalbumin in their native form, as well as in their modified structures and in fragments from these proteins was studied. By assessing the contribution to the total fluorescence of the exposed and buried Trp residues, and of the respective fluorescence quantum yields, the quantization of the number of Trp exposed to the solvent for all the species studied was possible. Both native proteins show an important increase in the number of Trp residues exposed to the solvent when treated with denaturing agents. The peptides L-II (aa 13-105) and?-I (aa 1-90) from lysozyme and?-lactalbumin, respectively, showed Trp residues with different degree of exposure, whereas the smaller fragments, L-III (aa 106-129) and?-II (aa 91 123), had all their Trp residues exposed to the solvent.
Photochemical reactivity of the homologous proteinsα-lactalbumin and lysozyme

The fluorescent behaviour and the photodynamic effect was studied in native and structurally modified lysozyme and?-lactalbumin. The Tyr residues in lysozyme and?-lactalbumin show different sensitivities to the photodynamic effect. The effect is zero in the case of Tyr from native lysozyme. In contrast, the Tyr residues in?-lactalbumin are susceptible to photooxidation, which indicates a greater degree of exposure to the solvent. The three His residues of?-lactalbumin have different degrees of exposure and show two different kinetics of photooxidation whereas the His residue of lysozyme is photooxidized with a single kinetic. Two photooxidation kinetics were obtained for the Trp residues of both native proteins, an indication that in both cases there are Trp residues that are differently exposed to the solvent. The wavelengths of maximum fluorescent emission of the Trp residues were different for the two proteins, an effect which can also be explained in terms of a difference in the environment of these residues. The modified form of these proteins emit at wavelengths longer than those of the native forms. When modified the proteins photooxidize with noticeably greater quantum yields.
Recovery of c-phycocyanin from the cyanobacteriumSpirulina maxima

Spirulina biomass was separated into two fractions which may have various uses. A phycocyanin fraction may provide a food colourant and biomarkers, and a protein-rich leftover may be useful as aquaculture feed. Activated charcoal adsorption, ultrafiltration and spray drying were used effectively to produce a high quality colourant grade phycocyanin, while activated charcoal adsorption, ammonium sulphate precipitation, dialysis and chromatography were effective in preparing reagent grade phycocyanin.
Determination of quark and gluon vacuum condensates from τ-lepton decay data

The values of the gluon and four-quark vacuum condensates are estimated using recent experimental data on the semileptonic ?-lepton decays ??v?+n?, which determine the vector and axialvector hadronic spectral functions. An optimal estimate is achieved through a systematic combined use Finite Energy, Laplace and Gaussian transform QCD sum rules. As a byproduct, the values of the dimensiond=8 vacuum condensates in the vector and axial-vector channels are also estimated.
Aspects of the ecology and growth of an intertidal juvenile population of Concholepas concholepas (Mollusca: Gastropoda: Muricidae) at Las Cruces, Chile

The habitat, density and growth rate for an intertidal population of Concholepas concholepas (Bruguire, 1789) were studied at Las Cruces, Chile (Lat. 33 30'S; Long. 71 38'W) during 1977 - 1978. The growth rate (3.67 mm month-1) was determined in a newly settled group, whose average length was 11.3 mm, and whose age was estimated at 3 months. The densities found ranged between 1.1 and 107.3 locos m-2. Based on these results, the time of settlement of C. concholepas was calculated; capsule deposition, maximum maturity and recruitment reported by other authors for different localities are discussed.
Comparative ecology of Lessonia nigrescens and Durvillaea antarctica (phaeophyta) in Central Chile

The Lessonia nigrescens-Durvillaea antarctica belt is the most conspicuous feature of the intertidal-subtidal boundary in Central Chile, with L. nigrescens attaining larger cover and biomass values than D. antarctica. Human predation of the otherwise competitively dominant D. antarctica has been suggested as accounting for its scarcity. Testing of this hypothesis included field studies of species distribution in places with and without human accessibility and various degrees of wave impact, comparative morphometric and population studies, evaluation of the ecologic role of the limpet-kelp association and comparative measurements of growth, reproduction and survival capacity. Results indicate that L. nigrescens and D. antarctica have morphologies typically adapted to habitats with different wave shock. Contrary to previous predictions, L. nigrescens appears as a plant better adapted for places with strong wave impact, which are the most common in Central Chile. Complete space monopolization by L. nigrescens is prevented by a series of adaptations of D. antarctica. Certain morphological forms of this species are less affected by wave action, allowing a population stock to persist even at the most exposed places. Boring into algal holdfasts by invertebrates weakens the mechanical resistance of old, eroded plants providing open space where juveniles of either species could settle. D. antarctica seems to take greater advantage of this primary space by means of a fugitive life history. Finally, the survival of D. antarctica increases if attached to the top of L. nigrescensholdfasts. It is therefore concluded that result of the interaction between these 2 brown algae depends on the degree of water impact. In sheltered habitats competitive displacement of L. nigrescens could occur but it is unlikely to be a continuous process. In exposed habitats D. antarctica is constantly removed by water movement, but persists because of a higher colonization rate.
The effect of certain ions on the internal stress of bright copper electrodeposits

The effect of low concentrations (0 100 mg 1?1) of F, Cl, Br, I, As, Sb, Bi, Ni, Zn, Fe, Ag, Te, Se, Pb, and S on the internal stress of bright copper electrodeposits was studied. The following solution containing 30 mg 1?1 of thiourea as a brightening additive was used as the electrolyte: CuSO4 5H2O (225 g l?1), H2SO4 (60g l?1). It is shown that the internal stress of copper electrodeposits can be considerably reduced by addition of Se(IV), Cl, Br, or I to the above electrolyte.
Effetti gemetici delľinquinamento in popolazioni lagunari di Balanus amphitrite Darwin (Cirripedia: Thoracica)

The present study concerns the genetic monitoring of three populations ofBalanus amphitrite from areas of the lagoon of Venice with different types of pollution. The comparison of gene and genotype frequencies and the multilocus structure among the considered populations suggest a strong influence of chemical pollutants on the genetic structure ofBalanus amphitrite, whereas thermal pollution does not seem to play a significant role. The results are consistent with the theory of natural selection. A possible selective mechanism is briefly discussed.
Efecto de extractos de Ascophylum nodosum y productos en base a silicio sobre la productividad y calidad de citrus reticulata blanco cv clemenluz sometida a estrés hídrico.

La falta de agua es uno de los principales factores que limitan el rendimiento y empeoran la calidad de fruto en mandarinos. Se realizó un estudio en campo dividido en dos ensayos, en árboles de 5 años de edad de Citrus reticulata blanco cv Clemenluz sobre el porta injerto C-35, con la finalidad de determinar los efectos de extractos del algas (Ascophyllum nodosum) y productos en base a silicio bajo condiciones de un estrés hídrico por falta de agua del 40%. Los tratamientos se definieron a partir de diferentes productos comerciales aplicados mediante riego o vía foliar y se aplicaron de manera mensual o quincenal desde el mes de diciembre 2018 hasta abril 2019. Se evaluaron parámetros de crecimiento vegetativo, fisiológicos y productivos. Ninguno de los tratamientos mejoró el rendimiento o la calidad de fruto de manera significativa, un extracto de algas combinado con aminoácidos mejoró la calidad de la fruta al tener una cáscara más delgada y un porcentaje de jugo más alto. Los tratamientos en base a silicio tuvieron efectos adversos bajo estas condiciones de estrés hídrico.
Adaptación Cultural del Cuestionario Grupo de Espiritualidad (CGES) en profesionales de la salud y pacientes de cuidados paliativos en Chile

La espiritualidad es una arista importante en la mantención y mejora de la calidad de vida del paciente paliativo. Se han encontrado varias relaciones positivas entre la espiritualidad con la salud mental y física. En el caso de los pacientes paliativos, la satisfacción de sus necesidades espirituales les pueden ayudar a encontrar calma y bienestar en el proceso del morir, disminuyendo complicaciones sintomáticas varias y los costos respectivos en salud. En nuestro país existe un desarrollo incipiente de los cuidados paliativos que se demuestra por la falta de instrumentos adaptados y validados que midan específicamente la espiritualidad. Por ello el siguiente proyecto buscó adaptar culturalmente el Cuestionario Grupo de Espiritualdad (CGES) de la Sociedad Española de Cuidados Paliativos, mediante las fases de consolidación de comité de expertos y de pre-test o entrevista cognitiva. Esta investigación cualitativa surge desde un paradigma constructivista, con un diseño de estudio de caso (collective case) cuyo caso es: “El grado de compresión de los ítems y constructos subyacentes del Cuestionario GES”. Se realizaron entrevistas cognitivas semiestructuradas en profundidad a 10 profesionales de la salud y 10 pacientes de cuidados paliativos. Los datos recabados se analizaron mediante Análisis Temático, una metodología que identifica, analiza y reporta patrones (o temas). Durante toda la investigación se utilizaron los criterios de rigor y de ética correspondientes. Se generó una propuesta de versión chilena del CGES que incluye consideraciones de los procesos cognitivos involucrados en la interpretación de los items originales (comprensión, llamada, juicio y respuesta), además de preguntas complementarias que ayudarían al profesional a adentrarse en el cuidado espiritual de los pacientes. En la adaptación cultural también se incorporó la evaluación global del instrumento, donde los participantes destacan lo adecuado del desarrollo, la integralidad de su visión y lo terapeútico de sus pregunta, y critican lo límitado de la metología cuantitativa de respuesta para abarcar información importante del paciente. Los participantes también reportan temas faltantes en el CGES (ej: muerte, sufrimiento, derivación, conclusión, etc.). La adaptación también dio cuenta mediante temas emergentes, de las dinámicas que surgen en la aplicación del cuestionario CGES: variabilidad, particularidad, mutabilidad y temporalidad.
Mapuche Poetry in the Age of Heritage

Heritage has the potential to foster introspection and reflection about the many communities co-existing within nation-states, and therefore, can lead to complex intercultural engagement. In Chile, recent efforts to catalogue intangible collective indigenous heritage ask Mapuche groups to self-represent univocally, giving way to a limited and static understanding of Mapuche culture and presence in Chile. A productive counterpoint can be found in Mapuche poetry, specifically, in the work of renowned poet Jaime Huenún. Though not officially considered within the realm of heritage, the literary representations I analyze emphasize the equivocal and entangled nature of indigenous and non-indigenous cultures in Chile. Focusing on the metatextual space of Huenún’s anthology prologues, I show how Huenún resignifies the notion of Mapuche community beyond the national framework of heritage, offering a resource for rethinking heritage’s role in creating productive spaces for interculturality.Heritage has the potential to foster introspection and reflection about the many communities co-existing within nation-states, and therefore, can lead to complex intercultural engagement. In Chile, recent efforts to catalogue intangible collective indigenous heritage ask Mapuche groups to self-represent univocally, giving way to a limited and static understanding of Mapuche culture and presence in Chile. A productive counterpoint can be found in Mapuche poetry, specifically, in the work of renowned poet Jaime Huenún. Though not officially considered within the realm of heritage, the literary representations I analyze emphasize the equivocal and entangled nature of indigenous and non-indigenous cultures in Chile. Focusing on the metatextual space of Huenún’s anthology prologues, I show how Huenún resignifies the notion of Mapuche community beyond the national framework of heritage, offering a resource for rethinking heritage’s role in creating productive spaces for interculturality.
Chapter 7 : Functional language typology : a discourse semantic perspective 1

Butler (2005: 4), in one of his many overviews of the major tenets of ‘functionalism,’ argues that “a functional theory must take fully into account the essential connection between language and (a) cognition and (b) the social and cultural context of language use.” What tends to be elided in these discussions is the place of co-textual relations as we attempt to interface (1) grammar and cognition or (2) grammar and social context. In this chapter we will address this elision from the perspective of discourse semantics, as developed in Systemic Functional Linguistic theory (hereafter SFL). In particular we will focus on some typological issues arising from consideration of the systems of ideation, conjunction, identification, periodicity, appraisal and negotiation as we try to understand how language has been shaped by its use.