Arrow ribbon graphs

We introduce an additional structure on ribbon graphs, arrow structure. We extend the Bollob\'as-Riordan polynomial to ribbon graph with this structure. The extended polynomial satisfies the contraction-deletion relations and naturally behaves with respect to the partial duality of ribbon graphs. We construct an arrow ribbon graph from a virtual link whose extended Bollob\'as-Riordan polynomial specializes to the arrow polynomial of the virtual link recently introduced by H.Dye and L.Kauffman. This result generalizes the classical Thistlethwaite theorem to the arrow polynomial of virtual links.Comment: to appear in Journal of Knot Theory and Its Ramification

A Bayesian approach to the estimation of maps between riemannian manifolds

Let \Theta be a smooth compact oriented manifold without boundary, embedded in a euclidean space and let \gamma be a smooth map \Theta into a riemannian manifold \Lambda. An unknown state \theta \in \Theta is observed via X=\theta+\epsilon \xi where \epsilon>0 is a small parameter and \xi is a white Gaussian noise. For a given smooth prior on \Theta and smooth estimator g of the map \gamma we derive a second-order asymptotic expansion for the related Bayesian risk. The calculation involves the geometry of the underlying spaces \Theta and \Lambda, in particular, the integration-by-parts formula. Using this result, a second-order minimax estimator of \gamma is found based on the modern theory of harmonic maps and hypo-elliptic differential operators.Comment: 20 pages, no figures published version includes correction to eq.s 31, 41, 4

Indices for the identification of biologically productive cashmere goats within farms

Objectively comparing cashmere goats with different cashmere production, mean fibre diameter (MFD) and staple length (SL) is difficult for farmers. We aimed to develop indices to enable cashmere producers to identify productive goats within their own farms once adjustments had been made for the primary determinants of cashmere production. That is we aimed to develop indices that identify goats and herds that biologically have a high fleece weight in relation to MFD and SL. We used a sample of 1244 commercial cashmere fleeces from goats originating from many Australian farms based in different environmental zones and a previously developed general linear model that related the logarithm of clean cashmere production (CCMwt) and any other potential determinant. In the present study, sub-models were investigated in order to develop new indices for comparing goats in the same farm, based on fleece characteristics and biological efficiency. New Index (MFD), equal to 6.02×CCMwt/1.1531MFD, was developed to identify animals of biologically high CCMwt in relation to their MFD. Unlike previously reported results that MFD is not a useful measurement for comparing the biological efficiency of cashmere goats across farms, the New Index (MFD) allows comparison of the biological efficiency of cashmere goats within farms. New Index (SL), equal to 2.70 × CCMwt/1.1414SL, was developed to identify animals of biologically high CCMwt in relation to their SL. New Index (SL) is very similar to the Clean Cashmere Staple Length Index (CCSLI) that had been previously reported for comparison of cashmere goats across farms, and thus the CCSLI can be usefully used for comparing the biological efficiency of cashmere goats both across and within farms. New Index MFD, SL = 8.90 × CCMwt/1.243(MFD+SL)/2 was developed to identify animals of biologically high CCMwt in relation to both their MFD and SL within farms, and provides useful information above using either New Index (MFD) or CCSLI. The indices can be presented in the same measurement units as fleece weight, which is a biological concept easily understood by cashmere producers, and enable comparisons to be made between animals using just one attribute, clean cashmere weight

Airborne laser topographic mapping results from initial joint NASA/US Army Corps of Engineers experiment

Initial results from a series of joint NASA/US Army Corps of Engineers experiments are presented. The NASA Airborne Oceanographic Lidar (AOL) was exercised over various terrain conditions, collecting both profile and scan data from which river basin cross sections are extracted. Comparisons of the laser data with both photogrammetry and ground surveys are made, with 12 to 27 cm agreement observed over open ground. Foliage penetration tests, utilizing the unique time-waveform sampling capability of the AOL, indicate 50 cm agreement with photogrammetry (known to have difficulty in foliage covered terrain)

Seasonal, lunar, and diel patterns in spawning by the giant barrel sponge, Xestospongia muta

Temporal patterns in giant barrel sponge (Xestospongia muta) spawning were compiled from 32 observations spanning 17 years and three Caribbean locations (Florida, Belize, and Haiti). The records were analyzed for patterns in seasonality, lunar periodicity, and diel rhythm to develop a predictive spawning window. Results indicate that spawning is concentrated from mid-April to late May. Most spawning events occurred around the first quarter moon; a smaller pulse occurred just before the third quarter moon. All spawning events were observed in the morning and fell within 779–987 min of the previous night’s sunset. Eggs of X. muta were all negatively buoyant and blanketed the areas within and surrounding the sponge; this limited gamete dispersal may be the driver behind heavily localized genetic retention

Much to do about identity: Successful women in science reflect on their school years

This study presents the recollections of 12 successful women in science duringtheir school years before postsecondary education. The participants shareddetailed descriptions of their science experiences through three semi-structured interviews. An identity works conceptual framework consisting offigured worlds, positioning, and agency constructs to portray the complexdynamics of their experiences was used to analyze the data. The following fourthemes emerged from the data analysis: participants had an early interest inmathematics and science; they were“stubbornly”persistent in science-figuredworlds; they engaged in science-figured worlds beyond school; and they posi-tioned themselves as science leaders. These findings add to the evolution of sci-ence identity development theoretical models because they are from anondeficit perspective. Participants engaged in identity work that advancedtheir science identities despite the gender biases in science-figured worlds.From a practical stance, girls and women could employ the agentic and posi-tive positioning identity work that the findings show to develop their scienceidentity in educational contexts. Science educators and researchers are encour-aged to structure figured worlds where girls feel empowered to enact identitywork to build strong science identities

Surface control system for the 15 meter hoop-column antenna

The 15-meter hoop-column antenna fabricated by the Harris Corporation under contract to the NASA Langley Research Center is described. The antenna is a deployable and restowable structure consisting of a central telescoping column, a 15-meter-diameter folding hoop, and a mesh reflector surface. The hoop is supported and positioned by 48 quartz cords attached to the column above the hoop, and by 24 graphite cords from the base of the antenna column. The RF reflective surface is a gold plated molybdenum wire mesh supported on a graphite cord truss structure which is attached between the hoop and the column. The surface contour is controlled by 96 graphite cords from the antenna base to the rear of the truss assembly. The antenna is actually a quadaperture reflector with each quadrant of the surface mesh shaped to produce an offset parabolic reflector. Results of near-field and structural tests are given. Controls structures and electromagnetics interaction, surface control system requirements, mesh control adjustment, surface control system actuator assembly, surface control system electronics, the system interface unit, and control stations are discussed

The allometric relationship between mean fibre diameter of mohair and the fleece-free liveweight of Angora goats over their lifetime

As mean fibre diameter (MFD) is the primary determinant of mohair price we aimed to quantify the lifetime changes in mohair MFDas Angora goats aged and grew. Measurements were made over 12 shearing periods on a population of Angora goats representing the current range and diversity of genetic origins including South African, Texan and interbred admixtures of these and Australian sources. Records of sire, dam, birthweight, birth parity, liveweight, fleece growth and fleece quality were taken for does and castrated males (wethers) (n = 267 animals). Fleece-free liveweights (FFLwt) were determined for each goat at shearing time by subtracting the greasy fleece weight from the liveweight recorded immediately before shearing. A restricted maximum likelihood growth curve model was developed for relating MFD to FFLwt, age and other measurements.Asimple way of describing the results is:MFD= k (FFLwt)b E; where k is a parameter that can vary in a systematic way with shearing(age), breed, weaning weight, sire, dam and individual; b is a parameter that is the same for nearly the whole study; and E are independent errors from a log-normal distribution. The analysis shows that ^b = 0.34, with s.e. (^b) = 0.021. Thus, mohair MFD was allometrically related to the cube root of FFLwt over the lifetime of Angora goats. However, the allometric proportionality constant differed in a systematic way with age at shearing, genetic strain, weaning weight, sire, dam and individual. For Texan-breed goats, MFD decreased as weaning weight increased (P = 0.00016). The findings indicate that management factors that affect liveweight and weaning weight have lifetime effects on mohair fibre diameter and therefore the value of mohair and the profitability of the mohair enterprise.<br /

Novel insights into the expression of CGB1 & 2 genes by epithelial cancer cell lines secreting ectopic free hCGβ

BACKGROUND Ectopic secretion of human chorionic gonadotrophin free beta (hCGβ) by epithelial cancer is associated with aggressive tumors which more readily metastasize, possibly by acting as an autocrine anti-apoptotic agent. hCGβ is encoded by six homologous CGB genes, with poorly-understood variable transcriptionally active expression profiles; CGB1 and CGB2 have always been considered pseudogenes. However, transcripts from CGB1 and -2 can be detected in placental, testicular and pituitary tissues. The expression and function of these genes in cancer is less well-known. MATERIALS AND METHODS Expression profiles of CGB genes in epithelial cancer cells by quantitative polymerase chain reaction (qPCR) were explored, along with the consequence of specific siRNA silencing of CGB1 and 2. Immunohistochemical and immunoassay techniques were used to detect the translation and secretion of hCGβ in these cells. RESULTS CGB1 and -2 gene transcripts were only detected in cells which secreted hCGβ. siRNA-mediated silencing of CGB1 and -2 transcripts significantly reduced secreted protein in concordance with a reduction in cell survival to a greater degree than that of other CGB genes. CONCLUSION CGB genes 1 and 2, previously considered as pseudogenes, are notably expressed by epithelial cancer cell lines. The transcription of these genes, but not other CGB genes, correlates with a functionally expressed protein and propensity for cancer growth