A remarkable new Anomiopus Westwood from Peru (Coleoptera: Scarabaeidae: Scarabaeinae)

Described and illustrated is a strikingly distinct new species of the scarabaeine genus Anomiopus Westwood, A. pishtaco (Coleoptera: Scarabaeidae), from the Amazonian lowlands of eastern Peru

Intensity self-pulsations in (GaAl)As injection lasers operating in an external cavity

We present an experimental and theoretical study of a self-pulsing (GaAl)As injection laser operating in an external cavity. We have observed suppression of the self-pulsations when the external cavity is in the range 6 < L < 10 cm. Suppression of self-pulsations can also be obtained by using a multimode graded index optical fiber as the external resonator. These results can be explained by a model which includes the effects of an external cavity and electron trapping. For long cavity lengths, the self-pulsation frequency locks to an external cavity harmonic with no significant quenching, as observed in some earlier experiments

Generation and Quenching of Intensity Pulsations in Semiconductor Lasers Coupled to External Cavities

The behavior of self-pulsing and nonpulsing lasers coupled to external cavities is investigated experimentally and theoretically. We investigate the dependence of the pulsation characteristics on the external cavity length using a saturable absorber model for self-pulsing lasers. It was found that quenching of self-pulsation occurs only for a certain limited range of external cavity length, and the frequencies of external-cavity induced pulsations lies within a certain range determined by the coupling coefficient. Small-signal analysis allows these ranges to be derived analytically. Hitherto, complex pulsation phenomena can be explained very intuitively by interpreting the combined laser-external cavity system as a microwave oscillator with a limited gain band and discrete mode structure

The genus Gromphas Brullé, 1837 in Peru (Coleoptera: Scarabaeidae: Scarabaeinae: Phanaeini)

The genus Gromphas Brullé (Coleoptera: Scarabaeidae) comprises four species, of which G. aeruginosa (Perty) and G. amazonica Bates are known to occur in Peru. This paper presents a revised description of Gromphas as well as illustrated diagnoses and distributional and ecological data on the Peruvian species

Woven Words: A Semiology of Clothing in Medieval Texts.

Much criticism in medieval studies has focused on Chrisitan allegory and its dissemination through Middle English poetry. Using recent insights into the nature of allegory in its medieval context, this study offers a new means of understanding allegory as it appears in the work of Chaucer and the Pearl-poet. Which ideas of figurality actually informed the works of these poets? The investigation into the influence of medieval textuality on Chaucer and the Pearl-poet has overlooked the image of the veil in the Middle Ages. This study asserts that instead of being a flat image, the veil provides us with a palpable means of understanding the ways in which Christian sign theory treated allegory. Chapter One reviews the semiology of clothing in exegesis as it appears in the image of the textualized body of Christ. It suggests that the origin of the vacillation between the perceived presence and absence of meaning in medieval allegory exists in the different readings of this body as both the revealer and reveiler of truth. The paradox of the Incarnational text provided the unstable foundation of medieval theories of textuality, both religious and secular. Chapters Two and Three focus on The Clerk\u27s Tale and Pearl to reveal how the poets who understood language to be simultaneously pre- and post-linguistic. In the way they identified this fundamental tension within allegory, Pearl and The Clerk\u27s Tale reveal through the semiology of clothing an appreciation for and keen awareness of the problem of allegory. The Pearl-poet questions the possibility of uncovering the spiritual res of allegory by demonstrating the endless reflexivity of the allegorical sign in the image of the Pearl-maiden. In The Clerk\u27s Tale, Griselda\u27s relationship to her garments asks us to reevaluate her role as the tale\u27s unchanging sentence. The Clerk\u27s Tale exposes how language creates and changes the reality it represents. Chaucer\u27s poetics critique the quest for an absolute and divinely inspired correspondence between language and truth and find it lacking

Studies of (GaAI)As injection lasers operating with an optical fiber resonator

The characteristics of an optical fiber external resonator in conjunction with (GaAl)As stripe geometry lasers are described. We have observed a 6–10% reduction in the threshold current and have obtained 150 ps pulses at gigahertz repetition rates. The fiber resonator has also been used to quench self‐pulsations in a (GaAl)As injection laser. In order to explain many of our results we have used a model that uses the conventional semiconductor rate equations modified by the addition of saturable electron traps and the effects of the external cavity. Our results predict many of the self‐locking effects observed in injection lasers operating in an external cavity. Furthermore, the degree of self‐locking will be a strong function of the external cavity length and the density of saturable absorbers

Opportunities and benefits for increasing transmission capacity between the US eastern and western interconnections

Historically, the primary justification for building wide-area transmission lines in the US and around the world has been based on reliability and economic criteria. Today, the influence of renewable portfolio standards (RPS), Environmental Protection Agency (EPA) regulations, transmission needs, load diversity, and grid flexibility requirements drives interest in high capacity wide-area transmission. By making use of an optimization model to perform long-term (15 years) co-optimized generation and transmission expansion planning, this work explored the benefits of increasing transmission capacity between the US Eastern and Western Interconnections under different policy and futures assumptions. The model assessed tradeoffs between investments in cross-interconnection HVDC transmission, AC transmission needs within each interconnection, generation investment costs, and operational costs, while satisfying different policy compliance constraints. Operational costs were broken down into the following market products: energy, up-/down regulation reserve, and contingency reserve. In addition, the system operating flexibility requirements were modeled as a function of net-load variability so that the flexibility of the non-wind/non-solar resources increases with increased wind and solar investment. In addition, planning reserve constraints are imposed under the condition that they be deliverable to the load. Thus, the model allows existing and candidate generation resources for both operating reserves and deliverable planning reserves to be shared throughout the interconnections, a feature which significantly drives identification of least-cost investments. This model is used with a 169-bus representation of the North American power grid to design four different high-capacity wide-area transmission infrastructures. Results from this analysis suggest that, under policy that imposes a high-renewable future, the benefits of high capacity transmission between the Eastern and Western Interconnections outweigh its cost. A sensitivity analysis is included to test the robustness of each design under different future assumptions and approximate upper and lower bounds for cross-seam transmission between the Eastern and Western Interconnections

New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest

Tesis por compendioEl presente proyecto de investigación está enfocado al desarrollo de sensores químicos fluoro-cromogénicos, para la detección y determinación de especies químicas de interés biológico, industrial y medioambiental de forma selectiva y con alta sensibilidad. En forma general, se busca el diseñar nuevos sistemas sensores basados en compuestos (receptores) formados por dos unidades: una unidad coordinante que interacciona con el anión a determinar y una unidad generadora de señal que alerta del reconocimiento molecular efectuado. Durante este estudio se están preparando diversas moléculas receptoras funcionalizandas con grupos modificadores de estructura para evaluar su influencia sobre las capacidades de detección y selectividad como receptores de especies específicas en diferentes condiciones y medios. Las diferentes aproximaciones en prueba implican a su vez el diseño y síntesis molecular, así como el análisis de las diferentes señales ópticas producidas en el reconocimiento, con el fin de diseñar sistemas de alta eficacia y eficiencia, y con posibilidades reales de aplicación.Santos Figueroa, LE. (2014). New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/43216TESISPremios Extraordinarios de tesis doctoralesCompendi