1,488 research outputs found

    Effects on Longitudinal Stability and Control Characteristics of a B-29 Airplane of Variations in Stick-force and Control-rate Characteristics Obtained Through Use of a Booster in the Elevator-control System

    Get PDF
    The longitudinal stability and control characteristics of a B-29 airplane have been measured with a control surface booster incorporated in the elevator-control system. The measurements were obtained with the booster operating to provide various control-force gradients and various maximum rates of control motion. Results are presented which show the effect of these booster parameters on the handling qualities of the test airplane

    A Synopsis of Melanthiaceae (Liliales) with Focus on Character Evolution in Tribe Melanthieae

    Get PDF
    Melanthiaceae s.l. comprises five tribes: Chionographideae, Heloniadeae, Melanthieae, Parideae, and Xerophylleae—each defined by distinctive autapomorphies. The most morphologically diverse tribe Melanthieae, now with seven genera, had not been subject to rigorous phylogenetic character study prior to the current series of investigations that also include an overview of the family. Data from our publications and studies underway are here assessed and integrated, providing a useful overview of Melanthiaceae, and especially of Melanthieae. The results of parsimony analyses of ITS (nuclear ribosomal) and trnL-F (plastid) DNA sequence data correlate with potentially synapomorphic phenotypic characters for genera of Melanthieae, including habit form, rootstock type, bulb shape, inflorescence structure, indumentum type, tepa! shape, nectary morphology, and ovary position. Sequence data also correlate well with the pattern of variation in chromosome number. The molecular and morphological data support generic recircumscription in Melanthieae and also validate several generalizations concerning character evolution within the tribe, as well as among the tribes of the family

    Scramble! Your Social Network Data

    Full text link

    Late Miocene to early Pliocene biofacies of Wanganui and Taranaki Basins, New Zealand: Applications to paleoenvironmental and sequence stratigraphic analysis

    Get PDF
    The Matemateaonga Formation is late Miocene to early Pliocene (upper Tongaporutuan to lower Opoitian New Zealand Stages) in age. The formation comprises chiefly shellbeds, siliciclastic sandstone, and siltstone units and to a lesser extent non-marine and shallow marine conglomerate and rare paralic facies. The Matemateaonga Formation accumulated chiefly in shelf paleoenvironments during basement onlap and progradation of a late Miocene to early Pliocene continental margin wedge in the Wanganui and Taranaki Basins. The formation is strongly cyclothemic, being characterised by recurrent vertically stacked facies successions, bounded by sequence boundaries. These facies accumulated in a range of shoreface to mid-outer shelf paleoenvironments during conditions of successively oscillating sea level. This sequential repetition of facies and the biofacies they enclose are the result of sixth-order glacio-eustatic cyclicity. Macrofaunal associations have been identified from statistical analysis of macrofossil occurrences collected from multiple sequences. Each association is restricted to particular lithofacies and stratal positions and shows a consistent order and/or position within the sequences. This pattern of temporal paleoecologic change appears to be the result of lateral, facies-related shifting of broad biofacies belts, or habitat-tracking, in response to fluctuations of relative sea level, sediment flux, and other associated paleoenvironmental variables. The associations also show strong similarity in terms of their generic composition to biofacies identified in younger sedimentary strata and the modern marine benthic environment in New Zealand

    Infrared spectroscopy of diatomic molecules - a fractional calculus approach

    Full text link
    The eigenvalue spectrum of the fractional quantum harmonic oscillator is calculated numerically solving the fractional Schr\"odinger equation based on the Riemann and Caputo definition of a fractional derivative. The fractional approach allows a smooth transition between vibrational and rotational type spectra, which is shown to be an appropriate tool to analyze IR spectra of diatomic molecules.Comment: revised + extended version, 9 pages, 6 figure

    Generic realignments in Maxillariinae (Orchidaceae)

    Get PDF
    Un reciente análisis filogenético de cuatro regiones de ADN para ca. 354 especies de la subtribu Maxillariinae indican fuertemente que el género Maxillaria, en su circunscripción tradicional, es altamente polifilético. Presentamos una nueva clasificación filogenética para Maxillariinae que reconoce 17 géneros. Los cambios necesarios incluyen: 1) la resurrección de los géneros Camaridium, Heterotaxis, y Ornithidium; 2) el reconocimiento de los recientes segregados genéricos Brasiliorchis (=Maxillaria sección Repentes), Christensonella (=Maxillaria sección Urceolatae), Nitidobulbon (en prensa), y una Sauvetrea recircunscrita (=Maxillaria sección Trigonae); 3) la adopción de los nuevos géneros Inti (=Maxillaria sección Polyphyllae), Mapinguari, Maxillariella (=Maxillaria secciones Ebulbes y Erectae), y Rhetinantha; 4) transferencias de Maxillaria sección Reflexae a Ornithidium, y Maxillaria sección Rufescens a Mormolyca; y 5) puesta en sinonimia de los géneros Adamanthus, Pseudomaxillaria, Psittacoglossum y Sepalosaccus (bajo Camaridium), Anthosiphon (bajo Cryptocentrum), Chrysocycnis (bajo Mormolyca), Dicrypta, Marsupiaria y Pentulops (bajo Heterotaxis), y Laricorchis, Neo-Urbania, y Siagonanthus (bajo Ornithidium). Algunos sinónimos nuevos al nivel de especie también son presentados.A recent phylogenetic analysis of four DNA regions for ca. 354 species of core Maxillariinae strongly indicate that the genus Maxillaria, as traditionally circumscribed, is grossly polyphyletic. We present a new phylogenetic classification for core Maxillariinae that recognizes 17 genera. Necessary realignments include: 1) resurrection of the genera Camaridium, Heterotaxis, and Ornithidium; 2) recognition of the recent segregates Brasiliorchis (=Maxillaria sect. Repentes), Christensonella (=Maxillaria sect. Urceolatae), Nitidobulbon (in press), and a recircumscribed Sauvetrea (=Maxillaria sect. Trigonae); 3) adoption of the new genera Inti (=Maxillaria sect. Polyphyllae), Mapinguari, Maxillariella (=Maxillaria sections Ebulbes and Erectae), and Rhetinantha; 4) transfers from Maxillaria sect. Reflexae to Ornithidium, and Maxillaria sect. Rufescens to Mormolyca; and 5) synonymizing of the genera Adamanthus, Pseudomaxillaria, Psittacoglossum, and Sepalosaccus (under Camaridium), Anthosiphon (under Cryptocentrum), Chrysocycnis (under Mormolyca), Dicrypta, Marsupiaria, and Pentulops (under Heterotaxis), and Laricorchis, Neo-urbania, and Siagonanthus (under Ornithidium). Some new synonyms at the specific level are also presented.National Science Foundation/[DEB-0234064]/NSF/Estados UnidosFundação de Amparo à Pesquisa do Estado de São Paulo/[01/08958-1]/FAPESP/BrasilConsejo Nacional de Ciencia y Tecnología/[]/CONACYT/MéxicoRoyal Botanic Gardens, Kew/[]//InglaterraAmerican Orchid Society/[]/AOS/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Jardín Botánico Lankester (JBL

    Phenotypic spectrum associated with de novo and inherited deletions and duplications at 16p11.2 in individuals ascertained for diagnosis of autism spectrum disorder

    Get PDF
    Background Recurrent microdeletions and microduplications of w555 kb at 16p11.2 confer susceptibility to autism spectrum disorder (ASD) in up to 1% of ASD patients. No physical or behavioural features have been identified that distinguish these individuals as having a distinct ASD subtype, but clinical data are limited. Methods We report five autistic probands identified by microarray analysis with copy number variation (CNV) of 16p11.2 (three deletions, two duplications). Each patient was assessed for ASD and dysmorphic features. We also describe a deletion positive 26-month-old female who has developmental delay (DD) and autistic features. Results Proband 1 (female with ASD, de novo deletion) is not dysmorphic. Proband 2 (male with autism, de novo deletion) and proband 3 and his brother (males with autism, inherited deletions) are dysmorphic, but the two probands do not resemble one another. The mother of proband 3 has mild mental retardation (MR), minor dysmorphism and meets the criteria for ASD. Proband 4 (dysmorphic autistic male, de novo duplication) had a congenital diaphragmatic hernia. Proband 5 (nondysmorphic ASD female with a duplication) has two apparently healthy duplication positive relatives. Probands 1 and 2 have deletion negative siblings with ASD and Asperger syndrome, respectively. Proband 6 (a female with DD and an inherited duplication) is dysmorphic, but has oligohydramnios sequence. Conclusions The phenotypic spectrum associated with CNV at 16p11.2 includes ASD, MR/DD and/or possibly other primary psychiatric disorders. Compared with the microduplications, the reciprocal microdeletions are more likely to be penetrant and to be associated with nonspecific major or minor dysmorphism. There are deletion positive ASD probands with a less severe phenotype than deletion negative ASD siblings underscoring the significant phenotypic heterogeneity.published_or_final_versio

    In search of phylogenetic congruence between molecular and morphological data in bryozoans with extreme adult skeletal heteromorphy

    Get PDF
    peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tsab20© Crown Copyright 2015. This document is the author's final accepted/submitted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it

    Phytoestrogens

    Get PDF
    Collectively, plants contain several different families of natural products among which are compounds with weak estrogenic or antiestrogenic activity toward mammals. These compounds, termed phytoestrogens, include certain isoflavonoids, flavonoids, stilbenes, and lignans. The best-studied dietary phytoestrogens are the soy isoflavones and the flaxseed lignans. Their perceived health beneficial properties extend beyond hormone-dependent breast and prostate cancers and osteoporosis to include cognitive function, cardiovascular disease, immunity and inflammation, and reproduction and fertility. In the future, metabolic engineering of plants could generate novel and exquisitely controlled dietary sources with which to better assess the potential health beneficial effects of phytoestrogens
    corecore