The effect of flight line spacing on radioactivity inventory and spatial feature characteristics of airborne gamma-ray spectrometry data

Airborne Gamma Spectrometry (AGS) is well suited to the mapping of radioactivity in the environment. Flight parameters (e.g. speed and line spacing) directly affect the rate of area coverage, cost, and data quality of any survey. The influences of line spacing have been investigated for data from inter‐tidal, coastal and upland environments with a range of <sup>137</sup>Cs activity concentrations and depositional histories. Estimates of the integrated <sup>137</sup>Cs activity (‘inventory’) within specified areas and the shapes of depositional features were calculated for subsets of the data at different line spacings. Features with dimensions greater than the line spacing show variations in inventory and area of less than 3%, and features with dimensions less than the line spacing show larger variations and a decreased probability of detection. The choice of line spacing for a task is dependent on the dimensions of the features of interest and required edge definition. Options for line spacing for different tasks are suggested. It is noted that for regional mapping, even 5–10 km line spacing can produce useful data

Oyster Mortality Studies in Virginia: Ill. Epizootiology of a Disease Caused by Haplosporidium costale Wood and Andrews

A short, sharp eplzootic disease of oysters on Seaside of Eastern Shore, Virginia, has been associated with a new pathogen, Haplosporidium costale Wood and Andrews. Native oysters in trays have shown closely timed May-June losses for three consecutive years. Losses at other seasons were small. May-June losses ranged from 12 to 14 percent in 1959 to 36 to 44 percent in 1960. James River oysters moved to Seaside showed higher losses than natives after a year of acclimation. Oysters in Bayside creeks revealed late summer losses caused by Dermocystidimn marinmn Mackin, Owens, and Collier rather than May-June deaths. The new pathogen was found in live oysters from March to July, and in a high proportion of gapers in May and June. The epizootiology is well established for these periods but unknown for the rest of the year. Increasing prevalence of another pathogen ( MSX ), causing Delaware Bay disease, has complicated mortality studies. Losses are most serious in older oysters which have been held beyond the usual period of culture. Careful timing of planting and early harvesting permit oystermen to a void serious losses

On Nichols algebras over PGL(2,q) and PSL(2,q)

We compute necessary conditions on Yetter-Drinfeld modules over the groups \mathbf{PGL}(2,q)=\mathbf{PGL}(2,\FF_q) and \mathbf{PSL}(2,q)=\mathbf{PSL}(2,\FF_q) to generate finite dimensional Nichols algebras. This is a first step towards a classification of pointed Hopf algebras with group of group-likes isomorphic to one of these groups. As a by-product of the techniques developed in this work, we prove that there is no non-trivial finite-dimensional pointed Hopf algebra over the Mathieu groups $M_{20}$ and $M_{21}=\mathbf{PSL}(3,4)$.Comment: Minor change

Immune-Mediated Inflammation May Contribute to the Pathogenesis of Cardiovascular Disease in Mucopolysaccharidosis Type I.

BackgroundCardiovascular disease, a progressive manifestation of α-L-iduronidase deficiency or mucopolysaccharidosis type I, continues in patients both untreated and treated with hematopoietic stem cell transplantation or intravenous enzyme replacement. Few studies have examined the effects of α-L-iduronidase deficiency and subsequent glycosaminoglycan storage upon arterial gene expression to understand the pathogenesis of cardiovascular disease.MethodsGene expression in carotid artery, ascending, and descending aortas from four non-tolerized, non-enzyme treated 19 month-old mucopolysaccharidosis type I dogs was compared with expression in corresponding vascular segments from three normal, age-matched dogs. Data were analyzed using R and whole genome network correlation analysis, a bias-free method of categorizing expression level and significance into discrete modules. Genes were further categorized based on module-trait relationships. Expression of clusterin, a protein implicated in other etiologies of cardiovascular disease, was assessed in canine and murine mucopolysaccharidosis type I aortas via Western blot and in situ immunohistochemistry.ResultsGene families with more than two-fold, significant increased expression involved lysosomal function, proteasome function, and immune regulation. Significantly downregulated genes were related to cellular adhesion, cytoskeletal elements, and calcium regulation. Clusterin gene overexpression (9-fold) and protein overexpression (1.3 to 1.62-fold) was confirmed and located specifically in arterial plaques of mucopolysaccharidosis-affected dogs and mice.ConclusionsOverexpression of lysosomal and proteasomal-related genes are expected responses to cellular stress induced by lysosomal storage in mucopolysaccharidosis type I. Upregulation of immunity-related genes implicates the potential involvement of glycosaminoglycan-induced inflammation in the pathogenesis of mucopolysaccharidosis-related arterial disease, for which clusterin represents a potential biomarker

Functional rescue of dystrophin deficiency in mice caused by frameshift mutations using Campylobacter jejuni Cas9

Duchenne muscular dystrophy (DMD) is a fatal, X-linked muscle wasting disease caused by mutations in the DMD gene. In 51% of DMD cases, a reading frame is disrupted because of deletion of several exons. Here, we show that CjCas9 derived from Campylobacter jejuni can be used as a gene editing tool to correct an out-of-frame Dmd exon in Dmd knockout mice. Herein, we used Cas9 derived from S. pyogenes to generate Dmd knockout (KO) mice with a frameshift mutation in Dmd gene. Then, we expressed CjCas9, its single-guide RNA, and the eGFP gene in the tibialis anterior muscle of the Dmd KO mice using an all-in-one adeno-associated virus (AAV) vector. CjCas9 cleaved the target site in the Dmd gene efficiently in vivo and induced small insertions or deletions at the target site. This treatment resulted in conversion of the disrupted Dmd reading frame from out-of-frame to in-frame, leading to the expression of dystrophin in the sarcolemma. Importantly, muscle strength was enhanced in the CjCas9-treated muscles, without off-target mutations, indicating high efficiency and specificity of CjCas9. This work suggests that in vivo DMD frame correction, mediated by CjCas9 has great potential for the treatment of DMD and other neuromuscular diseases

Leading-edge vortices elevate lift of autorotating plant seeds

As they descend, the autorotating seeds of maples and some other trees generate unexpectedly high lift, but how they attain this elevated performance is unknown. To elucidate the mechanisms responsible, we measured the three-dimensional flow around dynamically scaled models of maple and hornbeam seeds. Our results indicate that these seeds attain high lift by generating a stable leading-edge vortex (LEV) as they descend. The compact LEV, which we verified on real specimens, allows maple seeds to remain in the air more effectively than do a variety of nonautorotating seeds. LEVs also explain the high lift generated by hovering insects, bats, and possibly birds, suggesting that the use of LEVs represents a convergent aerodynamic solution in the evolution of flight performance in both animals and plants

A new species of stalked crinoid (Echinodermata) of possible Late Silurian age from central Newfoundland

A new fossil locality within a sequence previously assigned to the Middle Ordovician Baie D'Espoir Group in south-central Newfoundland contains fragmented crinoid columnals and brachiopods. Distinctive, pentastellate crinoid columnals, similar to those assigned to the monobathrid camerate Hexacrinites Austin and Austin by Russian authors, are named Hexacrinites? Pentastellatus n. sp. Nodal(?) columnals of this species have a circular, depressed articular facet, with a conical to bowl-like crenularium, a depressed, circular areola, a raised perilumen and a short, slender axial canal of pentagonal section. The oldest Hexacrinites sensu stricto are Late Silurian, suggesting that the fossiliferous strata have been incorrectly assigned to the Ordovician. Cross-sections of brachiopods from the same locality include an example that resembles several Early Silurian to Late Devonian pentameroid genera including Brooksina Kirk, 1922. Correlation with Late Silurian, bivalve-bearing strata SO km to the northeast would indicate that a major unconformity may occur above the fossiliferous Early and Middle Ordovician strata and the Early Ordovician ophiolite complexes. RÉSUMÉ Un nouvel emplacement de fossiles à I'intérieur d'une sequence auparavant attribute au groupe de l'Ordovicien moyen de Baie d'Espoir dans le centre-sud de Terre-Neuve renferme des fragments de columnales et de brachiopodes de crinoldes. Des columnales de crinoldes pentaétoilées caractéristiqucs, semblables à celles attributées à l’Hexacrinites Austin and Austin à loges monobathrides par des auteurs russes, sont baptisées nouvelle espèce pentastellatus d'Hexacrinites?. Les columnales nodales(?) de cette espèce sont pourvues d'une facette articulaire renfoncée et circulaire munie d'un crenularium allant de conique à bombé, d'une aréole circulaire renfoncie, d'un périlumen surélevé et d'un canal axial mince et court de section pentagonalc. Les plus anciens Hexacrinites, au sens strict, remontent au Silurien supérieur, ce qui permet de supposer qu'on a incorrectement attribué la strate fossilifère à l'Ordovicien. Des iéchantillons représentatifs de brachiopodes du même emplacement comprennent un exemple qui ressemble à plusieurs genres de pentaméroides datant du Silurien inférieur au Dévonien supérieur, notamment le Brooksina Kirk, 1922. Leur corrélation avec des strates renfermant des bivalves du Silurien supérieur à 50 km au nord-cst signale qu'une discordance importantc pourrait se présenter au-dessus des strates fossiliferes de l'Ordovicien inférieur ou moyen de même que des complexes d'ophiolites de l'Ordovicien inférieur. [Traduit par la rédaction

Reduction of carboplatin induced emesis by ondansetron.

Ondansetron is a selective 5-HT3 antagonist with significant antiemetic properties in patients receiving cytotoxic chemotherapy. Patients who had suffered severe vomiting on carboplatin alone (23 patients with ovarian carcinoma) or in combination (two patients with testicular cancer) despite intensive antiemetic regimens were treated with ondansetron, given as 8 mg immediately prior to carboplatin followed by 8 mg orally, 8 hourly for 5 days. Twenty-five patients received 58 courses of ondansetron. In the first 24 h after the first course of chemotherapy with ondansetron, 17 patients (68%) experienced no vomiting, five patients (20%) had almost complete control and the other three patients had partial control. During the subsequent 4 days slightly lesser control was achieved. Nausea was similarly controlled in most patients. Twenty-two patients stated a preference for ondansetron with future chemotherapy. Fourteen patients received additional chemotherapy with ondansetron and in only three patients did the efficacy of therapy lessen. Toxicity was mild and transient with headache and constipation predominant. No extrapyramidal reaction was seen. Sedation was absent. Ondansetron is highly effective in refractory vomiting associated with carboplatin chemotherapy. It may be particularly beneficial when an extrapyramidal reaction has occurred on previous antiemetics and when sedation is unacceptable

Triggered Star Formation in a Massive Galaxy at z=3.8: 4C41.17

Spectropolarimetric observations obtained with the W. M. Keck Telescope of the z=3.8 radio galaxy 4C41.17 show that the UV continuum emission from this galaxy, which is aligned with the radio axis, is unpolarized (P[2sigma] < 2.4%). This implies that scattered AGN light, which is generally the dominant contributor to the rest-frame UV emission in z~1 radio galaxies, is unlikely to be a major component of the UV flux from 4C41.17. The spectrum shows absorption lines that are similar to those detected in the spectra of the recently discovered population of star forming galaxies at z~2-3. A galaxian outflow may contribute partially to the low ionization absorption lines; however, the high velocity wings of the high ionization lines are unlikely to be dominated by a galaxian wind since the implied outflow mass is very large. The detection of stellar absorption lines, the shape of the SiIV profile, the unpolarized continuum, the inability of any AGN-related processes to account for the UV flux, and the similarity of the UV continuum spectra of 4C41.17 and the nearby starburst region NGC 1741B1 suggest that the UV light in 4C41.17 is dominated by young stars. If so, the implied star-formation rate is roughly 140-1100Msun/yr. We discuss the possibility that star formation in 4C41.17 was triggered by the radio source. Our data are consistent with the hypothesis that 4C41.17 is undergoing its major epoch of star formation at z~4, and that by z~1 it will have evolved to have spectral and morphological properties similar to those observed in known z~1 powerful radio galaxies.Comment: 28 pages (Latex text + figures); Accepted for publication in The Astrophysical Journal (Dec 1, 1997 issue

Quantum Computing and Hidden Variables I: Mapping Unitary to Stochastic Matrices

This paper initiates the study of hidden variables from the discrete, abstract perspective of quantum computing. For us, a hidden-variable theory is simply a way to convert a unitary matrix that maps one quantum state to another, into a stochastic matrix that maps the initial probability distribution to the final one in some fixed basis. We list seven axioms that we might want such a theory to satisfy, and then investigate which of the axioms can be satisfied simultaneously. Toward this end, we construct a new hidden-variable theory that is both robust to small perturbations and indifferent to the identity operation, by exploiting an unexpected connection between unitary matrices and network flows. We also analyze previous hidden-variable theories of Dieks and Schrodinger in terms of our axioms. In a companion paper, we will show that actually sampling the history of a hidden variable under reasonable axioms is at least as hard as solving the Graph Isomorphism problem; and indeed is probably intractable even for quantum computers.Comment: 19 pages, 1 figure. Together with a companion paper to appear, subsumes the earlier paper "Quantum Computing and Dynamical Quantum Models" (quant-ph/0205059