Self-Help Groups

“‘Self-Help Groups’ are … “... A way to start working that helps to build up the social connections which people find useful in support of their livelihoods objectives” “... Helping people to agree things and to speak together, giving people a stronger voice in decision-making and in negotiating with more powerful forces” “... A way of increasing the effectiveness of local actions” “... Providing easier access to micro-credit and other resources and services” (Pdf contains 4 pages).

Observations on the life history and identity of intraspecific groups of the anchoveta, Cetengraulis mysticetus, in Montijo Bay and Chiriquí Province, Panama

ENGLISH: Howard and Landa (1958) and Barrett and Howard (1961) have studied the life history of the anchoveta in most of the areas where this species occurs in important quantities. The Gulf of Panama was the only area of Panama included in these studies, as this was the only one from which sufficient samples were available. Berdegue (1958) compared certain meristic and morphometric characters of anchovetas from Montijo Bay and nine other areas of the eastern tropical Pacific Ocean. He found statistically significant differences, and concluded that the fish of the different areas belonged to separate "populations." Fish from Chiriquí province were not included in his study. Since the, completion of the above-mentioned studies, a number of collections of anchovetas from Montijo Bay and Chiriquí province have been obtained. In the present report use is made of this material to determine the salient facts regarding the life history of the anchoveta from these areas and to supplement the available knowledge of the identity of the intraspecific groups. Acknowledgment is extended to Dr. Milner B. Schaefer, formerly Director of Investigations, Inter-American Tropical Tuna Commission (now Director, Institute of Marble Resources, University of California), Mr. Clifford L. Peterson, Assistant Director of Investigations, and Mr. Edward F. Klima (now with the U. S. Bureau of Commercial Fisheries) for advice and assistance rendered to the project. The shrimp-boat samples were collected by Captains Robert Barrett, Stephen Barrett, and Chester McLean. SPANISH: Howard y Landa (1958) y Barrett y Howard (1961) han estudiado la historia natural de la anchoveta en la mayoría de las áreas en donde esta especie aparece en cantidades importantes. El Golfo de Panamá es la única area de Panamá incluida en estos estudios, ya que es la única de la cual hubo suficientes muestras disponibles. Berdegué (1958) camparó ciertos caracteres merístieos y morfométricos de la anehoveta del Golfo de Montijo y otras nueve áreas del Océano Pacífico Oriental Tropical. Encontró diferencias estadísticamente significativas e hizo la conclusión de que los peces de las diferentes áreas pertenecían a "poblaciones" separadas. Los peces de la Provincia de Chiriquí no fueron incluidos en su estudio. Desde la terminación de los estudios antes meneionados se obtuvieron varias recolecciones de anchovetas del Golfo de Montijo y de la Provincia de Chiriquí. En el presente informe se usó este material para determinar los hechos sobresalientes referentes a la historia natural de la anchoveta de estas áreas y suplir el conocimiento disponible de la identidadde los grupos intraespecíficos. Se hace extensivo un reconocimiento al Dr. Milner B. Schaefer, antiguo director de investigaciones de la Comisión Interamericana del Atún Tropical (ahora director del Institute of Marine Resources, University of California), al Sr. Clifford L. Peterson, asistente del director de investigaciones, y al Sr. Edward F. Klima (ahora can el U. S. Bureau of Commercial Fisheries) por su consejo y ayuda prestados en este proyecto. Las muestras de los barcos camaroneros fueron reeolectadas por los capitanes Robert Barrett, Stephen Barrett y Chester McLean

Estimation of the abundance of yellowfin tuna, Thunnus albacares, by age groups and regions within the Eastern Pacific Ocean

ENGLISH: Monthly estimates of the abundance of yellowfin tuna by age groups and regions within the eastern Pacific Ocean during 1970-1988 are made, using purse-seine catch rates, length-frequency samples, and results from cohort analysis. The numbers of individuals caught of each age group in each logged purse-seine set are estimated, using the tonnage from that set and length-frequency distribution from the "nearest" length-frequency sample(s). Nearest refers to the closest length frequency sample(s) to the purse-seine set in time, distance, and set type (dolphin associated, floating object associated, skipjack associated, none of these, and some combinations). Catch rates are initially calculated as the estimated number of individuals of the age group caught per hour of searching. Then, to remove the effects of set type and vessel speed, they are standardized, using separate weiznted generalized linear models for each age group. The standardized catch rates at the center of each 2.5 0 quadrangle-month are estimated, using locally-weighted least-squares regressions on latitude, longitude and date, and then combined into larger regions. Catch rates within these regions are converted to numbers of yellowfin, using the mean age composition from cohort analysis. The variances of the abundance estimates within regions are large for 0-, 1-, and 5-year-olds, but small for 1.5- to 4-year-olds, except during periods of low fishing activity. Mean annual catch rate estimates for the entire eastern Pacific Ocean are significantly positively correlated with mean abundance estimates from cohort analysis for age groups ranging from 1.5 to 4 years old. Catch-rate indices of abundance by age are expected to be useful in conjunction with data on reproductive biology to estimate total egg production within regions. The estimates may also be useful in understanding geographic and temporal variations in age-specific availability to purse seiners, as well as age-specific movements. SPANISH: Se calculan estimaciones mensuales de la abundancia del atún aleta amarilla por grupos de edad y regiones en el Océano Pacífico oriental durante 1970-1988, usando tasas de captura cerquera, muestras de frecuencia de talla, y los resultados del análisis de cohortes. Se estima el número de individuos capturados de cada grupo de edad en cada lance cerquero registrado, usando el tonelaje del lance en cuestión y la distribución de frecuencia de talla de la(s) muestra(s) de frecuencia de talla "más cercana/s)," "Más cercana" significa la(s) muestra(s) de frecuencia de talla más parecida(s) al lance cerquero en cuanto a fecha, distancia, y tipo de lance (asociado con delfines, con objeto flotante, con barrilete, con ninguno de éstos, y algunas combinaciones). Se calculan inicialmente las tasas de captura como el número estimado de individuos del grupo de edad capturado por hora de búsqueda. A continuación, para eliminar los efectos del tipo de lance y la velocidad del barco, se estandardizan dichas tasas, usando un modelo lineal generalizado ponderado, para cada grupo por separado. Se estima la tasa de captura estandardizada al centro de cada cuadrángulo de 2.5°-mes, usando regresiones de mínimos cuadrados ponderados localmente por latitud, longitud, y fecha, y entonces combinándolas en regiones mayores. Se convierten las tasas de captura dentro de estas regiones en números de aletas amarillas individuales, usando el número promedio por edad proveniente del análisis de cohortes. Las varianzas de las estimaciones de la abundancia dentro de las regiones son grandes para los peces de O, 1, Y5 años de edad, pero pequeñas para aquellos de entre 1.5 Y4 años de edad, excepto durante períodos de poca actividad pesquera. Las estimaciones de la tasa de captura media anual para todo el Océano Pacífico oriental están correlacionadas positivamente de forma significativa con las estimaciones de la abundancia media del análisis de las cohortes para los grupos de edad de entre 1.5 y 4 años. Se espera que los índices de abundancia por edad basados en las tasas de captura sean útiles, en conjunto con datos de la biología reproductiva, para estimar la producción total de huevos por regiones. Las estimaciones podrían asimismo ser útiles para la comprensión de las variaciones geográficas y temporales de la disponibilidad específica por edad a los barcos cerqueros, y también las migraciones específicas por edad. (PDF contains 35 pages.)

Möbius-like groups of homeomorphisms of the circle

A group G → Homeo_+(S^1) is a Möbius-like group if every element of G is conjugate in Homeo(S^1) to a Mobius transformation. Our main result is: given a Mobus like like group G which has at least one global fixed point, G is conjugate in Homeo(S^1) to a Möbius group if and only if the limit set of G is all of S^1 . Moreover, we prove that if the limit set of G is not SI, then after identifying some closed subintervals of S^1 to points, the induced action of G is conjugate to an action of a Möbius group.

We also show that the above result does not hold in the case when G has no global fixed points. Namely, we construct examples of Möbius-like groups with limit set equal to S^1, but these groups cannot be conjugated to Möbius groups.

Descriptive set theory and the ergodic theory of countable groups

The primary focus of this thesis is on the interplay of descriptive set theory and the ergodic theory of group actions. This incorporates the study of turbulence and Borel reducibility on the one hand, and the theory of orbit equivalence and weak equivalence on the other. Chapter 2 is joint work with Clinton Conley and Alexander Kechris; we study measurable graph combinatorial invariants of group actions and employ the ultraproduct construction as a way of constructing various measure preserving actions with desirable properties. Chapter 3 is joint work with Lewis Bowen; we study the property MD of residually finite groups, and we prove a conjecture of Kechris by showing that under general hypotheses property MD is inherited by a group from one of its co-amenable subgroups. Chapter 4 is a study of weak equivalence. One of the main results answers a question of Abért and Elek by showing that within any free weak equivalence class the isomorphism relation does not admit classification by countable structures. The proof relies on affirming a conjecture of Ioana by showing that the product of a free action with a Bernoulli shift is weakly equivalent to the original action. Chapter 5 studies the relationship between mixing and freeness properties of measure preserving actions. Chapter 6 studies how approximation properties of ergodic actions and unitary representations are reflected group theoretically and also operator algebraically via a group's reduced C^*-algebra. Chapter 7 is an appendix which includes various results on mixing via filters and on Gaussian actions.

Surface-enhanced Raman scattering substrate fabricated by femtosecond laser direct writing

We report the fabrication of a novel surface-enhanced Raman scattering (SERS) substrate with a controllable enhancement factor (EF) using femtosecond laser direct writing on Ag+-doped phosphate glass followed by chemical plating at similar to 40 degrees C. Silver seeds were first photoreduced using a femtosecond laser in a laser-irradiated area and then transformed into silver nanoparticles of suitable size for SERS application in the subsequent chemical plating. Rhodamine 6G was used as a probing molecule to investigate the enhancement effect of a Raman signal on the substrate. Nearly homogenous enhancement of the Raman signal over the Substrate was achieved, and the EF of the substrate was controlled to some extent by adjusting fabrication parameters. Moreover, the ability of forming a SERS platform in an embedded microfluidic chamber would be of great use for establishing a compact lab-on-a-chip device based on Raman analysis.

Class two p groups as fixed point free automorphism groups

Suppose that AG is a solvable group with normal subgroup G where (|A|, |G|) = 1. Assume that A is a class two odd p group all of whose irreducible representations are isomorphic to subgroups of extra special p groups. If p^c ≠ r^d + 1 for any c = 1, 2 and any prime r where r^2d+1 divides |G| and if C_G(A) = 1 then the Fitting length of G is bounded by the power of p dividing |A|.

The theorem is proved by applying a fixed point theorem to a reduction of the Fitting series of G. The fixed point theorem is proved by reducing a minimal counter example. IF R is an extra spec r subgroup of G fixed by A₁, a subgroup of A, where A₁ centralizes D(R), then all irreducible characters of A₁R which are nontrivial on Z(R) are computed. All nonlinear characters of a class two p group are computed.

Graphs and Groups

This project is a combination of graphs and group theory in which the aim is to describe the automorphism group of some specific families of graphs. Finally, an example of the application of automorphism groups in reaction graphs is shown. The project is written in english.

Normal structures and automorphism groups of t-designs

Combinatorial configurations known as t-designs are studied. These are pairs ˂B, ∏˃, where each element of B is a k-subset of ∏, and each t-design occurs in exactly λ elements of B, for some fixed integers k and λ. A theory of internal structure of t-designs is developed, and it is shown that any t-design can be decomposed in a natural fashion into a sequence of “simple” subdesigns. The theory is quite similar to the analysis of a group with respect to its normal subgroups, quotient groups, and homomorphisms. The analogous concepts of normal subdesigns, quotient designs, and design homomorphisms are all defined and used.

This structure theory is then applied to the class of t-designs whose automorphism groups are transitive on sets of t points. It is shown that if G is a permutation group transitive on sets of t letters and ф is any set of letters, then images of ф under G form a t-design whose parameters may be calculated from the group G. Such groups are discussed, especially for the case t = 2, and the normal structure of such designs is considered. Theorem 2.2.12 gives necessary and sufficient conditions for a t-design to be simple, purely in terms of the automorphism group of the design. Some constructions are given.

Finally, 2-designs with k = 3 and λ = 2 are considered in detail. These designs are first considered in general, with examples illustrating some of the configurations which can arise. Then an attempt is made to classify all such designs with an automorphism group transitive on pairs of points. Many cases are eliminated of reduced to combinations of Steiner triple systems. In the remaining cases, the simple designs are determined to consist of one infinite class and one exceptional case.

A palavra-bolha: um estudo do conto de Lygia Fagundes Telles

Neste estudo é analisado o conto da paulistana Lygia Fagundes Telles sob dois enfoques principais: a investigação a respeito do narrador e o exame das técnicas utilizadas na escritura lygiana em si. Em relação ao narrador, examinam-se as inovações trazidas pela escritora a partir do diálogo com a tradição machadiana de narrativa. Toma-se como ponto de partida da análise o conto Missa do Galo: variações sobre o mesmo tema (1977), escrito por Lygia Fagundes Telles sobre o conto homônimo de Machado de Assis. No que concerne ao segundo aspecto, a escrita lygiana em si, são examinadas técnicas que resultam no que se chamará de palavra-bolha, ou seja, uma escritura na qual a característica primordial é a leveza narrativa, mesmo nos contos onde está presente a tragicidade, e investiga-se, através dessa técnica, o tipo de realismo presente no conto lygiano. A expressão palavra-bolha foi escolhida a partir do título de um dos contos da autora, A estrutura da bolha de sabão. Com o objetivo de analisar a palavra-bolha, ou seja, as técnicas lygianas de escritura, foi realizada uma divisão didática em quatro grupos de temas, nos quais foram encaixados e examinados os contos escolhidos como amostragens

Keep an "eye" on the text: The Use of Self-mention in the Academic Writing of Experts

One of the most controversial inquiries in academic writing is whether it is admissible to use first person pronouns in a scientific paper or not. Many professors discourage their students from using them, rather favoring a more passive tone, and thus causing novices to avoid inserting themselves into their texts in an expert-like manner. Abundant research, however, has recently attested that negotiation of identity is plausible in academic prose, and there is no need for a paper to be void of an authorial identity. Because in the course of the English Studies Degree we have received opposing prompts in the use of I, the aim of this dissertation is to throw some light upon this vexed issue. To this end, I compiled a corpus of 16 Research Articles (RAs) that comprises two sub-corpora, one featuring Linguistics RAs and the other one Literature RAs, and each, in turn, consists of articles written by American and British authors. I then searched for real occurrences of I, me, my, mine, we, us, our and ours, and studied their frequency, rhetorical functions and distribution along each paper. The results obtained certainly show that academic writing is no longer the faceless prose that it used to be, for I is highly used in both disciplines and varieties of English. Concerning functions, the most typically used roles were the use of I to take credit for the writer’s research process, and also those involving plural forms. With respect to the spatial disposition, all sections welcomed first person pronouns, but the Method and the Results/Discussion sections seem to stimulate their appearance. On the basis of these findings, I suggest that an L2 writing pedagogy that is mindful not only of the language proficiency, but also of the students’ own identity may have a beneficial effect on the composition of their texts.