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El objetivo del presente estudio fue determinar la prevalencia de parásitos intestinales en cachorros comercializados en la ciudad de Puno y evaluar la posible asociación de las variables grupo racial y tipo de comercialización (formal, informal) con la presentación de parasitismo intestinal. Se tomaron muestras fecales de 172 cachorros entre 1 y 4 meses de edad, sin distinción de sexo y grupo racial, del mercado informal, así como de veterinarias y tiendas de mascotas (formal). Las muestras fueron procesadas por las técnicas de examen directo y de concentración por flotación con solución de sulfato de zinc al 33% (GE 1.18). De las 172 muestras, 90 evidenciaron formas parasitarias (huevos, quistes u ooquistes), representando una prevalencia de 52.3%. Las prevalencias de parásitos intestinales en cachorros de raza pura y mestizos fueron de 44.2 y 60.5%, respectivamente, y de cachorros del comercio informal y formal fueron de 66.3 y 38.4%, respectivamente. Las especies encontradas fueron Dipylidium caninum, Ancylostoma caninum, Toxascaris leonina, Toxocara canis, Trichuris spp, Giardia spp, Isospora spp y Sarcocystis spp. Se observaron 11 casos de bi-parasitismo, uno de tri-parasitismo y uno de tetra-parasitismo. El tipo de comercialización estuvo asociado a la presencia de parasitismo intestinal (p

Uno de los principales problemas que se plantean los estudiantes de nivel secundario al concluir sus estudios consiste en escoger correctamente la profesión a seguir. Cuando esta decisión no es tomada con la madurez suficiente y siguiendo la vocación, se presentan los problemas consecuentes que van desde un deficiente rendimiento académico, hasta terminar por abandonar la carrera elegida (deserción) con pérdida de tiempo y dinero, o culminar una profesión sin llegar a estar satisfecho consigo mismo, lo que conlleva a la mediocridad e incompetencia. El objetivo del presente estudio fue determinar si la vocación y la elección de la carrera de Medicina Veterinaria y Zootecnia están relacionadas con el rendimiento académico de los estudiantes de una universidad privada de Lima, Perú. Se evaluaron 171 alumnos divididos en tres grupos de acuerdo con su rendimiento académico (alto, medio y bajo) y su nivel de estudios por ciclos lectivos (iniciales, intermedios y finales). El instrumento de evaluación fue una encuesta de 36 preguntas que abarcó cuatro dimensiones de la vocación profesional: satisfacción con la profesión elegida, interés por obtener una profesión, autoconfianza, y habilidades y destrezas. Se concluye que ninguna de las cuatro dimensiones se relaciona con el rendimiento académico. La dimensión autoconfianza fue estadísticamente significativa respecto al nivel de estudios, donde se determina que, mientras más alto sea el nivel alcanzado, mayor es la autoconfianza., One of the main problems that students of high school pose when concluding their studies consists in choosing wisely the profession to follow. When this decision is not taken with sufficient maturity and following the vocation, the consequent problems encompass a poor academic performance, desertion with loss of time and money, or culminate a profession without satisfaction, which leads to mediocrity and incompetence. The aim of this study was to determine if the vocation and the choice of the career of Veterinary Medicine and Zootechnics are related to the academic performance of the students of a private university in Lima, Peru. A total of 171 students were distributed into three groups according to their academic performance (high, medium and low) and their level of studies by academic semesters (initial, intermediate and final). The evaluation instrument was a survey of 36 questions covering four dimensions of professional vocation: satisfaction with the chosen profession, interest in obtaining a profession, self-confidence, and skills and abilities. It is concluded that none of the four dimensions were related to academic performance. The self-confidence dimension was statistically significant with respect to the level of studies, meaning that the higher the level reached, the greater the self-confidence.

A 65-year-old woman suffered from swollen parotid and submandibular glands in July 2005, and sicca of the eyes and oral cavity arose in October 2005. We diagnosed her as having Mikulicz's disease based on magnetic resonance imaging of the head, gallium scintigraphy, and a lip biopsy in June 2006. After prednisolone 10 mg/day was commenced, her salivary glands shrank slightly. Although the amount of prednisolone had been tapered to 7 mg/day by May 2007, her serum IgG rebounded. In January 2008, hachimijiogan extract granules 7.5 g/day were introduced. Swelling of the salivary glands disappeared and her serum IgG level decreased. In May 2008, the amount of prednisolone was tapered successfully to 6 mg/day. Mikulicz's disease is a corticosteroid-sensitive disease, but in this case steroid resistance made treatment difficult. Based on this case, we performed functional assays of P-glycoprotein with calcein-AM, which demonstrated that hachimijiogan can reverse drug resistance.

Evalúa cuantitativamente la expresión de los ARN mensajeros (ARNm) de los factores de transcripción T-bet, STAT-1 y STAT-4 y de las citoquinas interleucina (IL) 12, IL-2, interferón gamma (IFN-γ) y factor de necrosis tumoral alfa (TNF-α) involucrados en la activación y desarrollo de los linfocitos Th1 de la mucosa intestinal de crías de alpacas (Vicugna pacos) de tres grupos de 1-8, 10-21 y 22-47 días de edad, alimentadas en rebaños con pasto natural en la sierra sur del Perú. Obtiene muestras de una longitud de 2 cm de la porción media del yeyuno de crías de alpacas clínicamente sanas de la Estación IVITA Maranganí (Cusco, Perú), las que fueron almacenadas a -196°C y procesadas en el Laboratorio de Inmunología de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos (Lima, Perú). Extrae los ARN totales y desarrolla la PCR tiempo real con transcripción inversa (RT-PCR). Mide los valores de Ct (ciclo umbral, cycle treshold) y Tm (temperatura de disociación, temperatura de melting) de los productos del RT-PCR y emplea la técnica de cuantificación relativa 2-ΔΔCt a fin de evaluar la expresión de los ARNm de los factores mencionados respecto al control calibrador (fetos) en los tres grupos etáreos, empleándose como gen constitutivo de referencia a GAPDH. Las expresiones de T-bet, STAT-1 y STAT-4 muestran una tendencia positiva proporcional a la edad, siendo de 35, 6 y 3 veces lo expresado por el calibrador el grupo de 22-47 días de edad, respectivamente. Asimismo, las cinéticas de expresión en IL-2, IFN-γ y TNF-α muestran una tendencia positiva proporcional a la edad siendo de 26, más de cien y 5 veces lo expresado por el calibrador en el grupo de animales de 22-47 días de edad, respectivamente (p0.05). Concluye que la expresión de T-bet y STAT-1, factores transcripcionales activados por interferón gamma, se incrementa con la edad, así como también de las citoquinas involucradas en la respuesta inmune Th1, a diferencia de la expresión de STAT-4 e IL-12 que estadísticamente no difiere significativamente en los tres grupos etarios. Tesis

El presente estudio tuvo como objetivo redescribir morfo-anatómicamente a Lamanema chavezi en sus tres estadios parasitarios (huevo, larva de tercer estadío, adulto) utilizando la técnica de microscopía óptica y microscopía electrónica de barrido. Se trabajó con alpacas (Vicugna pacos) sacrificadas en el Camal Municipal de la provincia de Melgar, Puno, Perú. Los estadios adultos fueron colectados del intestino delgado aplicando el método de Travassos; los huevos fueron colectados de heces de animales parasitados mediante la técnica de flotación; y parte de los huevos obtenidos fueron incubados para la obtención de larvas mediante proceso mecánico. Los principales hallazgos incluyen la presencia del rudimento de corona foliácea, seis papilas cefálicas, características de crestas del sinlophe, presencia de papilas en la cara dorsal de los lóbulos laterales de la bolsa copulatríz, alas en las espículas, y características de los huevos y larvas L3. Se obtuvo la caracterización fenotípica y se complementa el conocimiento de la morfo-anatomía de L. chavezi con fines de diagnóstico y establecer un ámbito taxonómico., This study aimed to morpho-anatomically redescribe Lamanema chavezi in the three parasitic stages (egg, third stage larvae and adult) using optical microscopy and scanning electron microscopy. Samples were collected from alpacas (Vicugna pacos) in the municipal slaughterhouse of Melgar province, Puno, Peru. Adult specimens were collected from the small intestine using the Travassos method; eggs were collected from stool samples in infected animals by the flotation technique; and some of the collected eggs were incubated for obtaining larvae by mechanical process. The main findings include the presence of foliated crown rudiment, six cephalic papillae, synlophe ridges features, presence of papillae on the bursal dorsal side in the lateral lobes, spicules alae characteristics, and eggs and L3 larvae features. The results allowed the phenotypic characterization and complement the knowledge of the morpho-anatomy ofL. chavezi for diagnostic purposes and sets a taxonomic level.

A dry method of the powder preparation for tantalum solid electrolytic capacitor was studied using particle omposition equipment. The effects of paticle size and concentration of PMMA binder on the powder characteristics and the frequency response of impedance of the coducted powder was investigated in detail.It was confirmed that the existence state of binder in a dry method differs with that of a wet method by SEM photographs. The impedance behavior of powder bed can be described by the model of the existence state of binder.

This paper studies an (S, s) pricing model from the perspective of inflation and price competition in search markets. I present a model in which consumers'search technologies can influence firms' price setting, price dispersion, and the market structure. The result shows that although price competition among firms is more intensified in markets where consumers' search technologies are more efficient, price inflation is counter-intuitively, more likely to increase monopoly power of firms and to stimulate entry in these markets. The model also provides new empirical implications for firms' price setting behaviors.

This paper presents a search-theoretic model where middlemen can emerge endogenously to intermediate between ex ante homogeneous buyers and sellers in the presence of coordination frictions. Middlemen set price to compete in the market, and hold an inventory to provide a high matching service. I show that middlemen's inventories can mitigate trade imbalances and interact with price competition, generating an interesting tradeoff for the equilibrium price determination. The competitive limit emerges when middlemen guarantee excess demand will never occur. Conditions are characterized under which middlemen carry out the short-side principle for the market price to be Walrasian.

The three chapters of this dissertation contribute to the understanding of strategic firm behavior in oligopolistic markets. In particular, I link spatial market features to standard competition analysis, which enables new perspectives to explain market outcomes in geographically defined markets and provide applications to the grocery retail industry. Chapter 1 studies the importance of returns to product differentiation and distribution economies for a firm’s optimal location choice. Inspired by the empirical work of Holmes (2011), I introduce endogenous distribution costs in the model of Hotelling (1929). The proposed model shows an interesting trade-o between demand and cost considerations when a firm plays a hybrid location strategy. Given the location of local distribution centers and agents’ displacement cost parameters, it is shown that, under certain conditions, the optimal locations of the firms are in the interior of the Hotelling line rather than at the edges of the line. The supply-cost effect which drives this result diminishes with the distance of the distribution center from the market so that the scale of the distribution area also becomes determinant for an optimal location strategy. Chapter 2 investigates empirically the effect of anticipated price competition and distribution costs in firms’ location choices within an oligopolistic market. I set up a static location-price game of incomplete information in which retailers choose their locations based on (firm-)location-specific characteristics, the expected market power and the expected degree of price competition. In particular, I tie the firms’ strategic location incentives to the population distribution using the concept of captive consumers. This approach is in line with theoretical spatial price competition models and does not require price or quantity data. I address the computational difficulties of the estimation using mathematical programming with equilibrium constraints. Applied to grocery stores operated by the two main conventional supermarket chains in the US, the model confirms the existence of benefits of spatial differentiation for the firms’ profits and provides evidence that the firms anticipate price competition and distribution costs in their site selections. Chapter 3 studies empirically the volatility of retail price indexes at the store level as a result of changes in the local market structure within an urban market. Using a reduced-form pricing equation, I decompose the potential competition effect in the effect of incumbent retailers and the effect of new grocery store openings. Considering the Spanish supermarket industry, which is strongly regulated, I make use of panel data and use a first-difference approach to estimate a distributed-lag model. The results suggest an instantaneous price reaction to entry which is smaller than the long-term competition effect. Possible explanations are constrained price- exibility for incumbent firms in the short run or difficulties of the entrant in establishing themselves as coequal rivals. I find that this gradual price reaction is especially pronounced for supermarkets positioned in the middle price-segment, and the strongest price reaction has been found for high-price retailers., I gratefully acknowledge that this research was funded by the University Carlos III de Madrid and the grant ECO2012-31358 from the Spanish Ministry of Education., Programa Oficial de Doctorado en Economía, Presidente: Tobias Kretsemer; Secretario: Ulrich J. Wagner; Vocal: Guillermo Caruana