Inexplicable inefficiency of avian molt? Insights from an opportunistically breeding arid-zone species, Lichenostomus penicillatus

The majority of bird species studied to date have molt schedules that are not concurrent with other energy demanding life history stages, an outcome assumed to arise from energetic trade-offs. Empirical studies reveal that molt is one of the most energetically demanding and perplexingly inefficient growth processes measured. Furthermore, small birds, which have the highest mass-specific basal metabolic rates (BMR_m), have the highest costs of molt per gram of feathers produced. However, many small passerines, including white-plumed honeyeaters (WPHE; Lichenostomus penicillatus), breed in response to resource availability at any time of year, and do so without interrupting their annual molt. We examined the energetic cost of molt in WPHE by quantifying weekly changes in minimum resting metabolic rate (RMR_min) during a natural-molt period in 7 wild-caught birds. We also measured the energetic cost of feather replacement in a second group of WPHEs that we forced to replace an additional 25% of their plumage at the start of their natural molt period. Energy expenditure during natural molt revealed an energy conversion efficiency of just 6.9% (±0.57) close to values reported for similar-sized birds from more predictable north-temperate environments. Maximum increases in RMR_min during the molt of WPHE, at 82% (±5.59) above individual pre-molt levels, were some of the highest yet reported. Yet RMR_min maxima during molt were not coincident with the peak period of feather replacement in naturally molting or plucked birds. Given the tight relationship between molt efficiency and mass-specific metabolic rate in all species studied to date, regardless of life-history pattern (Efficiency (%) = 35.720•10^-0.494BMRm; r² = 0.944; p =<0.0001), there appears to be concomitant physiological costs entrained in the molt period that is not directly due to feather replacement. Despite these high total expenditures, the protracted molt period of WPHE significantly reduces these added costs on a daily basis.

Genes involved in thoracic exoskeleton formation during the pupal-to-adult molt in a social insect model, Apis mellifera

Background: The insect exoskeleton provides shape, waterproofing, and locomotion via attached somatic muscles. The exoskeleton is renewed during molting, a process regulated by ecdysteroid hormones. The holometabolous pupa transforms into an adult during the imaginal molt, when the epidermis synthe3sizes the definitive exoskeleton that then differentiates progressively. An important issue in insect development concerns how the exoskeletal regions are constructed to provide their morphological, physiological and mechanical functions. We used whole-genome oligonucleotide microarrays to screen for genes involved in exoskeletal formation in the honeybee thoracic dorsum. Our analysis included three sampling times during the pupal-to-adult molt, i.e., before, during and after the ecdysteroid-induced apolysis that triggers synthesis of the adult exoskeleton. Results: Gene ontology annotation based on orthologous relationships with Drosophila melanogaster genes placed the honeybee differentially expressed genes (DEGs) into distinct categories of Biological Process and Molecular Function, depending on developmental time, revealing the functional elements required for adult exoskeleton formation. Of the 1,253 unique DEGs, 547 were upregulated in the thoracic dorsum after apolysis, suggesting induction by the ecdysteroid pulse. The upregulated gene set included 20 of the 47 cuticular protein (CP) genes that were previously identified in the honeybee genome, and three novel putative CP genes that do not belong to a known CP family. In situ hybridization showed that two of the novel genes were abundantly expressed in the epidermis during adult exoskeleton formation, strongly implicating them as genuine CP genes. Conserved sequence motifs identified the CP genes as members of the CPR, Tweedle, Apidermin, CPF, CPLCP1 and Analogous-to-Peritrophins families. Furthermore, 28 of the 36 muscle-related DEGs were upregulated during the de novo formation of striated fibers attached to the exoskeleton. A search for cis-regulatory motifs in the 5′-untranslated region of the DEGs revealed potential binding sites for known transcription factors. Construction of a regulatory network showed that various upregulated CP- and muscle-related genes (15 and 21 genes, respectively) share common elements, suggesting co-regulation during thoracic exoskeleton formation. Conclusions: These findings help reveal molecular aspects of rigid thoracic exoskeleton formation during the ecdysteroid-coordinated pupal-to-adult molt in the honeybee.

Efecto citotóxico de la melatonina en células de leucemia humana Molt-3

Programa de doctorado: Clínica e Investigación Terapéutica.

Sermo de la S. Conquista de la molt insigne noble, leal, e coronada ciutat de Valencia, predicat en la ... esglesia metropolitana de dita ciutat a 9 de Octubre any 1666 ... per lo R. Docttor Gaspar Blay Arbuxech, prebere de la Real Congregacio del Oratori ...

Sign.: A-I4

De part dels molt Illustres senyors Presidents y Concell del Batallò se notifica y fa a saber ab las presents als Iurats y Vniuersitats de Cover [i. e. Covet] que ... toca a pagar ... en la taula de Cervera ... en compte del Batallò

Notificación a los jurados y universidad de Covet de las 4 libras y 1 hombre en el repartimiento que les ha correspondido del Consell del Batalló

Asentats en terra Cento, y Tito van referint tot lo que hiaurà en Valencia en estes reals festes y Tito queda molt ansios de trobarse ya en elles [Texto impreso]

Hay un ejemplar encuadernado con: Relacion de la entrada que hizieron en la ciudad de Denia, Reyno de Valencia, las armas de la Magestad Catolica, del Rey nuestro Señor Carlos IIJ [sic] ... el dia 18 de agosto de 1705. (XVIII/1688).

Chiste nou y divertit [Texto impreso] : Escoltenme señores qu'els apresisa y oirán el gran chasco que es cas de risa. Este ha pasat en un poble qu'es molt nomenat, y Alboraya es diu.

Contiene : Trovo Nou

Conversa entre Albert y Pascual molt crítica, molt gustosa, molt interesant, molt instructiva per desvaneixer preocupacions y per ilustrarse [Texto impreso] ; en decimas

Publicado en Barcelona : En la oficina de la Viuda Pla

Gran historia de un pollí [Texto impreso] : burro, ase, bestia y animal ; y molt desgraciat per una petita ilusió

Encuadernado en : Literatura de cordel

Coloqui del nas [Texto impreso] : coloqui nou y entretengut, pera riure y pasar lo tems despues de la pancha plena, y no de palla de faves, ni safanories, ahon se referix un cas molt grasiós que pasà en un poble...

Hay un ejemplar encuadernado con: Romans, y coloqui nou, pera divertir el humor y desterrar la melancolia, yà que no tenim dinès ... (NP849.91/3085).

Rahonament y coloqui nou de Nelo el Tripero [Texto impreso] : en el que es referix els grans casos que li pasaren chic molt habil pera el estudio de la uña ; natural de valensia, fill del carrer de Cañete, en lo demés que vorá el curiós lector

Hay un ejemplar encuadernado con: Romans, y coloqui nou, pera divertir el humor y desterrar la melancolia, yà que no tenim dinès ... (NP849.91/3085).

Rahonament y coloqui nou de Nelo el Tripero [Texto impreso] : en el qu'es referix els grans casos que li pasaren ; chic molt hábil pera el estudio de la uña ; natural de Valensia, fill del carrer de Cañete, en lo demés que vorá el curiós lector

Hay un ejemplar encuadernado con: Romans, y coloqui nou, pera divertir el humor y desterrar la melancolia, yà que no tenim dinès ... (NP849.91/3085).

Coloqui nou y entretegut, pera riure y pasar lo temps, despues de la pancha plena, y no de palla de faves ni safanories : ahon se referix un cas molt graciós, que pasá en un Poble, com ho vorá el curiós letor [Texto impreso]

Hay un ejemplar encuadernado con: Romans, y coloqui nou, pera divertir el humor y desterrar la melancolia, yà que no tenim dinès ... (NP849.91/3085).