378 research outputs found

    VUV Fourier-transform absorption study of the Lyman and Werner bands in D2

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    An extensive survey of the D2 absorption spectrum has been performed with the high-resolution VUV Fourier-transform spectrometer of the DESIRS beamline at the SOLEIL synchrotron. The frequency range of 90 000-119 000 cm-1 covers the full depth of the potential wells of the B 1{\Sigma}+u, B' 1{\Sigma}+u, and C 1{\Pi}u electronic states up to the D(1s) + D(2\ell) dissociation limit. Improved level energies of rovibrational levels have been determined up to respectively v = 51, v = 13, and v = 20. Highest resolution is achieved by probing absorption in a molecular gas jet with slit geometry, as well as in a liquid helium cooled static gas cell, resulting in line widths of ~0.35 cm-1. Extended calibration methods are employed to extract line positions of D2 lines at absolute accuracies of 0.03 cm-1. The D1{\Pi}u and B" 1{\Sigma}+u electronic states correlate with the D(1s) + D(3\ell) dissociation limit, but support a few vibrational levels below the second dissociation limit, respectively v = 0-3 and v = 0-1, and are also included in the presented study. The complete set of resulting level energies is the most comprehensive and accurate data set for D2. The observations are compared with previous studies, both experimental and theoretical.Comment: 13 pages, 6 figures. The second set of Tables (Tables I-IV after the references), is auxiliary materia

    Esocoid fishes

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    49 p. : ill. ; 24 cm.Includes bibliographical references (p. 41-49)."In both the Esocidae and the Umbridae, phyletic rends involve reduction of cephalic sensory canals and elaboration of pitlines. Advanced characters of this sensory system indicate interrelationships among Recent species, most notably a close relationship between Dallia and Umbra. The Eocene Palaeoesox and the Oligocene Proumbra are attributable to the Umbridae and are probably closely related to Umbra. The historical biogeography of the Umbridae may involve a secondary distribution (Umbra limi, U. pygmaea) in east North America. A relationship between esocoids and galaxiids is unsupported, but a relationship between clupeomorphs and elapomorphs is supported by the structure of the cephalic canal system"--P [1]

    Teleostean fishes

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    30 p. : ill. ; 24 cm.Includes bibliographical references (p. 28-30)."This study completes a review of hyobranchial structure for Recent fishes of the order Clupeifromes. Its results support previously suggested phyletic trends involving reduction in number of branchiostegal rays, reduction and loss of gill-arch dentition, and elaboration of epibranchial organs within clupeiform fishes. Certain advanced characters of the gill arches characterize some of the major groups of Cluepiformes. On this basis it has been possible to arrive at a more precise conception of the interrelationships of these major groups. One result has been the splitting off of the Pristigasteridae from the Clupeidae. The problem of subdividing the families Engraulidae and Clupeidae is discussed from the standpoint of gill-arch structure"--P. 27

    Notes on the dermal skeleton of vertebrates

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    26 p. : ill. ; 24 cm.Includes bibliographical references (p. 24-26)."Within the buccopharyngeal cavity of many Recent sharks, there occurs a well-developed dermal skeleton, consisting of numerous, independent, non-growing denticles (placoid scales). It is apparent that the extent of this dermal skeleton, from the jaw margin to the pharyngo-esophogeal boundary, is a feature primitive for the Gnathostomata. Secondary reductions in the extent of this dermal skeleton are apparent in some Recent sharks. In others, pharyngeal denticles participate in the formation of specialized structures (pharyngeal pads), apparently analogous to the consolidated pharyngeal tooth plates of teleostomes. These observations lead to the hypothesis that the dermal skeleton of modern elasmobranchs is primitively subdivided, that is, in a primary micromeric condition. The relevance of this hypothesis is discussed in the context of a comparative theory of the dermal skeleton of vertebrates"--P. 24

    Teleostean fishes

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    31 p. : ill. ; 24 cm.Includes bibliographical references (p. 26-31)."Advanced characters of the lower jaw suggest that the Eocene Phareodus is an osteoglossine, the Cretaceous Ichthyodectiformes (Ichthyodectidae and Saurodontidae) are taeniopaedians, the Cretaceous Pachyrhizodontidae are clupeomorphs or euteleosteans, the Cretaceous Bananogmiidae are taeniopaedians, and the Cretaceous and Eocene Diplomystus agree with Recent Clupeidae and Chirocentridae. It is suggested that Phareodus (as Phareodontini) be included in the Osteoglossinae, and that the Ichthyodectiformes, Pachyrhizodontidae, and Bananogmiidae be classed as Teleostei, taxa incertae sedis. Advanced characters of the caudal skeleton of Pachyrhizodus and Bananogmius may prove useful in recognizing related forms"--P. [1]

    Why do patients decline surgical trials? Findings from a qualitative interview study embedded in the Cancer Research UK BOLERO trial (Bladder cancer: Open versus Lapararoscopic or RObotic cystectomy)

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    Background Surgical trials have typically experienced recruitment difficulties when compared with other types of oncology trials. Qualitative studies have an important role to play in exploring reasons for low recruitment, although to date few such studies have been carried out that are embedded in surgical trials. The BOLERO trial (Bladder cancer: Open versus Lapararoscopic or RObotic cystectomy) is a study to determine the feasibility of randomisation to open versus laparoscopic access/robotic cystectomy in patients with bladder cancer. We describe the results of a qualitative study embedded within the clinical trial that explored why patients decline randomisation. Methods Ten semi-structured interviews with patients who declined randomisation to the clinical trial, and two interviews with recruiting research nurses were conducted. Data were analysed for key themes. Results The majority of patients declined the trial because they had preferences for a particular treatment arm, and in usual practice could choose which surgical method they would be given. In most cases the robotic option was preferred. Patients described an intuitive ‘sense’ that favoured the new technology and had carried out their own inquiries, including Internet research and talking with previous patients and friends and family with medical backgrounds. Medical histories and lifestyle considerations also shaped these personalised choices. Of importance too, however, were the messages patients perceived from their clinical encounters. Whilst some patients felt their surgeon favoured the robotic option, others interpreted ‘indirect’ cues such as the ‘established’ reputation of the surgeon and surgical method and comments made during clinical assessments. Many patients expressed a wish for greater direction from their surgeon when making these decisions. Conclusion For trials where the ‘new technology’ is available to patients, there will likely be difficulties with recruitment. Greater attention could be paid to how messages about treatment options and the trial are conveyed across the whole clinical setting. However, if it is too difficult to challenge such messages, then questions should be asked about whether genuine and convincing equipoise can be presented and perceived in such trials. This calls for consideration of whether alternative methods of generating evidence could be used when evaluating surgical techniques which are established and routinely available

    Conformal smectics and their many metrics

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    We establish that equally spaced smectic configurations enjoy an infinite-dimensional conformal symmetry and show that there is a natural map between them and null hypersurfaces in maximally symmetric spacetimes. By choosing the appropriate conformal factor it is possible to restore additional symmetries of focal structures only found before for smectics on flat substrates

    Using a commercially available DNA extraction kit to obtain high quality human genomic DNA suitable for PCR and genotyping from 11-year-old saliva saturated cotton spit wads

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    <p>Abstract</p> <p>Background</p> <p>We sought to describe the integrity of human genomic DNA extracted from saliva saturated cotton spit wads stored at -20°C for approximately 11 years. 783 spit wad samples were collected from an ADHD sample population (Vermont Family Study) during 1996–2000. Human genomic DNA was extracted from the spit wads using a commercially available kit; QIAamp DNA Blood Midi Kit (Qiagen, Inc., Valencia, CA.) with a few modifications.</p> <p>Results</p> <p>The resulting DNA yield was more than adequate for genetic analysis and ranged from approximately 1 μg to a total of 80 μg (mean 17.3 μgs ± 11.9 μgs). A<sub>260</sub>/A<sub>280 </sub>ratios for the human genomic DNA extracted from the spit wads was consistently within the generally acceptable values of 1.7–2.0, with the lowest purity being 1.70, and a mean value of 1.937 ± 0.226 for the 783 samples. The DNA also was suitable for PCR reactions as evidenced by the amplification of the serotonin-transporter-linked polymorphic region, 5HTTLPR. 5HTTLPR is a functional polymorphism in the promoter region of the serotonin transporter gene (<it>HTT, SLC6A4</it>, or <it>SERT</it>), consisting of two intensively studied alleles. 770 of the 783 samples (98.3%) produced fragments after PCR of the expected size with primers specific for 5HTTLPR.</p> <p>Conclusion</p> <p>High quality and abundant genomic DNA can be successfully retrieved from saliva saturated cotton spit wads using the commercially available kit, QIAamp DNA Blood Midi Kit from Qiagen, Inc. Furthermore, the DNA can be extracted in less than 3 hours and multiple samples can be processed simultaneously thus reducing processing time.</p

    Gizzard shads

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    p. 133-206 : ill., maps ; 27 cm.Includes bibliographical references (p. 180-203)."The Indo-Pacific fishes commonly called gizzard shads include two tribes (the Anodontostomatini and Clupanodontini) and at least 12 species (Anodontostoma chacunda, Gonialosa manmina, G. modesta, Nematalosa arabica, N. come, N. erebi, N. galatheae, new species, N. japonica, N. nasus, N. vlaminghi, new combination, Clupanodon punctatus and C. thrissa). These species are generally better defined and more easily recognized by nonmeristic characters than by counts of scales, fin rays, vertebrae, ventral scutes, and predorsal bones. The North American gizzard shads include one tribe (Dorosomatini) and, as currently recognized, five species (Dorosoma anale, D. cepedianum, D. chavesi, D. smithi, and D. (Signalosa) petenense), defined primarily on the basis of meristic characters. This paper reviews the taxonomy of the Indo-Pacific species and provides a key for their identification, an account of their variation and distribution, and an analysis of their scientific literature. For North American species, references to recent literature are included. The gut of the gizzard shads differs from that of other clupeoids in having a third primary flexure. The tribes recognized are based partly on the variations of the third flexure"--P. 135

    Fetal membrane bacterial load is increased in histologically confirmed inflammatory chorioamnionitis: A retrospective cohort study

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    Introduction It is widely debated whether fetal membranes possess a genuine microbiome, and if bacterial presence and load is linked to inflammation. Chorioamnionitis is an inflammation of the fetal membranes. This research focussed on inflammatory diagnosed histological chorioamnionitis (HCA) and aimed to determine whether the bacterial load in fetal membranes correlates to inflammatory response, including histological staging and inflammatory markers in HCA. Methods Fetal membrane samples were collected from patients with preterm spontaneous labour and histologically phenotyped chorioamnionitis (HCA; n = 12), or preterm (n = 6) and term labour without HCA (n = 6). The bacterial profile of fetal membranes was analysed by sequencing the V4 region of the 16S rRNA gene. Bacterial load was determined using qPCR copy number/mg of tissue. The association between bacterial load and bacterial profile composition was assessed using correlation analysis. Results Bacterial load was significantly greater within HCA amnion (p = 0.002) and chorion (p = 0.042), compared to preterm birth without HCA. Increased bacterial load was positively correlated with increased histological staging (p = 0.001) and the expression of five inflammatory markers; IL8, TLR1, TLR2, LY96 and IRAK2 (p=<0.050). Bacterial profiles were significantly different between membranes with and without HCA in amnion (p = 0.012) and chorion (p = 0.001), but no differences between specific genera were detected. Discussion Inflammatory HCA is associated with infection and increased bacterial load in a dose response relationship. Bacterial load is positively correlated with HCA severity and the TLR signalling pathway. Further research should investigate the bacterial load threshold required to generate an inflammatory response in HCA
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