1,986 research outputs found
Assisted reproductive technology in Europe 2007 : results generated from European registers by ESHRE
No full textPeer reviewe
The Whole Counsel of God: A Tribute to E. Herbert Nygren
No full textHerb Nygren has served Taylor University faithfully for over twenty years. As chair of the Department of Biblical Studies, Christian Education, and Philosophy, he has modelled sound teaching and solid scholarship. Upon retirement, he leaves us a legacy of dedication, service, and love for Christ. The members of his department offer these essays as a small token of our esteem.https://pillars.taylor.edu/ayres-collection-books/1019/thumbnail.jp
Studies on head trauma complications with special reference to mild traumatic brain injury
No full textTraumatic brain injury (TBI) is a recognised public health problem. Patients with mild traumatic brain injury (MTBI) represent the main part of the total TBI population attending hospital. The aim of this thesis was to study some clinically important aspects of post-acute complications and long-term consequences after head trauma with special reference to MTBI. The pathophysiological basis of persisting complaints, which are reported by a substantial subgroup of adult patients with MTBI, is far from clear. A computerised tomography (CT) examination is most often used to detect brain tissue damage in the acute setting. Nevertheless, it is generally considered that CT scanning and other neuroimaging techniques might be insensitive to minor structural and functional abnormalities and that there is a need for other, more sensitive methods. It has been suggested that biochemical markers such as the protein S 1 00B are useful, both for the acute diagnosis and to predict persistent complaints.In a prospective cohort of patients with a primarily uncomplicated MTBI, corresponding to an ordinary brain concussion, the mixed form S 1 00B as well as two more specific forms, S 1 00A 1 B and S 1001313, were analysed in sera in order to examine their diagnostic and predictive value. Serum concentrations of the specific form, S 1 00A 1 B, were elevated in 64% of the patients who had sustained an MTBI and the corresponding figure for the mixed form, S 1 00B, was 4 1 %, when compared to non-inj ured persons. Using a control group with mild orthopaedic injuries, S 1 00B did not differentiate the trauma groups, while S 1 00A1 B concentrations were significantly higher in the MTBI group (pThe early, clinical follow-up of patients with MTBI must consider the risk of delayed intracranial complications. Data on the rate and risk factors of these complications are scarce. By conducting a case-control study, utilising the high-quality Inpatient Registry available in Sweden, we demonstrated that the rate of these complications in patients who have been discharged after uncomplicated, hospitalised observation, is low (0.13%) and that it declines during the first three weeks post-injury. Identified risk factors were clinical severity grade (OR 2.0 (Cl 1.2-3.6)) and male gender (OR 2.2 (Cl 1.4-3.5)). We could not demonstrate any protective effect of an early CT scan. TBI has long been considered a possible risk factor for brain tumour but previous studies have yielded inconsistent results. By conducting a population-based cohort study, utilising the Swedish Inpatient Registry as well as the Cancer Registry, we found evidence that TBI is not a risk factor for brain tumour (SIR 1.0 (Cl 0.9-1.2)).List of scientific papersI. Nygren de Boussard C, Fredman P, Lundin A, Andersson K, Edman G, Borg J (2004). "S100 in mild traumatic brain injury." Brain Injury (In Print) II. Nygren de Boussard C, Lundin A, Karlstedt D, Edman G, Bartfai A, Borg J (2004). "S100 and cognitive impairment after mild traumatic brain injury." (Submitted) III. Nygren de Boussard C, Belleco R, af Geijerstam J-L, Borg J, Adami J (2004). "Delayed intracranial complications after concussion - a population-based nested case-control study in Sweden." (Submitted)IV. Nygren C, Adami J, Ye W, Bellocco R, af Geijerstam JL, Borg J, Nyren O (2001). "Primary brain tumors following traumatic brain injury--a population-based cohort study in Sweden. " Cancer Causes Control 12(8): 733-7 https://pubmed.ncbi.nlm.nih.gov/11562113</p
Growth hormone and the heart in children
No full textBackground and Aims: The fact that growth hormone (GH) influences cardiovascular structure and function is well established through both human and animal studies. Despite being secreted in a pulsatile fashion, only the impact of peak GH concentrations on cardiac parameters has previously been reported, and the time-dependency of cardiovascular effects during GH treatment has not been detailed. The aims of this pediatric study were (i) to establish the expression of GH-receptor (GH-R) and insulin-like growth factor I (IGF-I) mRNA locally in the heart in children of different ages, (ii) to study in detail the relationship between the heart and endogenous GH secretion pattern, (iii) to study the cardiovascular effects of GH treatment and (iv) to examine organ/tissue-specific responses to GH.
Patients & Methods: Two trials were conducted. In the first, a cardiac biopsy was taken from 18 children undergoing heart surgery. GH-R and IGF-I mRNA were quantified by real-time polymerase chain reaction. In the second trial, 153 short prepubertal children were randomized to receive either a standard or an individualized GH dose. Echocardiography, blood pressure measurements and electrocardiography were performed at study start, and after 3 months, 1 year and 2 years of GH treatment.
Results: GH-R and IGF-I mRNA was found in all children studied. There was a significant relationship between their relative amounts (r=0.75, p<0.001), and body mass index was correlated with the relative expression of both genes (r=0.59, p=0.01 and r=0.50, p=0.04 respectively). Cardiac dimensions were not correlated with peak endogenous GH concentration but were negatively correlated with GH trough levels (r= –0.41, p<0.001) and positively correlated with GH secretion rate above baseline level (r=0.44, p<0.001). During treatment, a biphasic, time-dependent, cardiac response was seen. Initially, there was an increase in both standard deviation scores (SDS) for left ventricular (LV) diameter in diastole SDS (95% confidence interval (CI) for the increase in SDS from baseline to 3 months (ΔLVDdSDS0–3m): 0.05 to 0.36) and LV wall thickness, exemplified by septal thickness (ΔIVDdSDS0–3m: 95% CI 0.08 to 0.54). At 2 years, wall thickness returned to baseline values (ΔIVDdSDS0–24m: 95% CI -0.41 to 0.06) but LV diameter remained increased (ΔLVDdSDS0–24m: 95% CI 0.19 to 0.47). The heart was also found to be more responsive than both skeletal muscle and bone tissue to GH treatment. The dose resulting in a 50% response (ED50%) was as low as 33 µg/kg/d (90% confidence bounds: 24–38 µg/kg/d)) for LVDd compared with an ED50% of 51 (47–56) µg/kg/d for longitudinal growth and 57 (52–65) µg/kg/d for IGF-I.
Conclusion: With the presence of local GH-R and high sensitivity of the heart to GH, cardiac tissue is a primary target for GH. The GH trough levels seem to be of greater importance for cardiac dimensions than the peak GH concentrations, and the response to GH treatment is time-dependen
Antonbruunia sociabilis Mackie, Oliver & Nygren, 2015, sp. nov.
No full textAntonbruunia sociabilis sp. nov. Figs 1–4 Material examined. NE Atlantic: Scotland, Hatton-Rockall Basin, FRV Scotia, cruise 0712S, Station S 12283 a, 57 ° 57 ’N 15 ° 33 ’W, 1187-1200 m, Jackson 460 Otter trawl, 23 June 2012. Antonbruunia removed from among arborescent lateral body pouches of three Thyasira scotiae types (NMW- Z.2012.074.4- 5); eight, nine, and two specimens, last including holotype (NMW-Z.2012.074.6) and one paratype (NMW-Z.2012.074.7). Remaining types. Four paratypes (NMW-Z.2012.074.8), one paratype (NMW-Z.2012.074.9 dissected), one paratype (NMW-Z.2012.074.10 SEM), six paratypes (NMW-Z.2012.074.11) and one paratype (NMW- Z.2012.074.12 SEM). Four specimens were selected for sequencing; one voucher (NMW-Z.2012.074.13) yielded the sequences registered with GenBank (Table 1). Description. Holotype entire, maximum width 1.08 mm (including parapodia), 18.5 mm long for prostomium and 48 segments. Paratypes ranging from 0.56–1.28 mm wide, 5.2–22.6 mm long, and 32–52 segments. Body long and slender, dorsally arched and ventrally flat, lacking ventral groove. Head and anterior 5 segments narrow; segments thereafter rapidly increasing in size (Fig. 1 A–B), reaching maximum in anterior third of body, rapidly decreasing in posterior region. Cuticle smooth and shiny on best preserved specimens. Pygidium lobulate, ventro-laterally with single pair of tapered pygidial cirri (Figs 1 D, 2 D). Prostomium subtrapezoidal, with rounded anterior margin, lacking eyes (Fig. 1 A). Pair of antero-ventral palps, somewhat conical, basally expanded and distally tapered. Pair of antero-dorsolateral antennae, of similar shape to palps, but broader and longer (Fig. 2 A–B). Median antenna of similar size and shape to palps, arising mid-dorsally near posterior margin of prostomium (Fig. 1 A,B). Nuchal organs elliptical ciliated grooves, positioned dorsolaterally between posterior prostomium and anterior margin of segment 1 (Fig. 2 B). Peristomium ventrally fused with prostomium and segment 1; delineation between prostomium and segment 1 only distinct dorsally and laterally. Mouth ventral, transverse, slit-like (Fig. 2 A–B). Two pairs of tapered tentacular cirri on segment 1, superior cirri 1.5 to 2 times as long as inferiors; parapodia and chaetae lacking. Pharynx muscular, axial, short and narrow, occupying anterior three segments; proboscis short and bulbous when extruded (Fig. 2 C), jaws lacking. Gut tubular, with markedly wider lumen from anterior to middle of chaetiger 3. Gut caecae from chaetiger 3 as pair of small lateral pouches; caecae increase in size over following 2–3 chaetigers, extending into parapodia. By chaetiger 6 or 7, distally tapered caecae reach into posterior parts of parapodia, just below dorsal cirri; caecae decrease in size in posterior half to third of body. Gut caecae revealed through methyl green staining; caecae appearing as opaque white unstained masses either side, extending laterally into the parapodia. Parapodia simple, short cuff-like, lacking any marked pre- or post-chaetal structures. Dorsal cirri above or slightly dorso-posterior to parapodia; cirri somewhat conical with broad bases and tapering cirriform tips of variable extension (Figs 1 A–C & 3 A–B). Ventral cirri positioned below or slightly posterior to neurochaetae. Ventral cirri of anterior and posterior parapodia short, conical with bluntly pointed tips (Fig. 3 A,D). Those of median body larger, more rounded, or rounded with tiny sharply pointed tips (Figs 1 C, 3 C). Anterior parapodia supported by two parallel, robust and distally pointed neuroaciculae; increasing to three aciculae by about chaetiger 6 or 7. Single notoaciculae with sharply tapering tips arise separate from neuroaciculae (Fig. 1 C). Each notoacicula directed forward into anterior part of parapod, tip ending anterior to and level with uppermost neurochaetae, well in advance of dorsal cirrus (Fig. 1 B,C); in slide preparations notoacicula may seem closer to dorsal cirrus than reality. Neurochaetae numerous in anterior and mid body region, disposed in two bundles; superior bundle compact, inferior bundle broader with chaetae extending more dorsally around acicular lobe on posterior side (Figs 1 B, 3 E). Number of chaetae similar in each bundle, usually slightly more in inferior bundle; two bundles together totalling about 30–35 chaetae in anterior parapodia, but increasing to 45–50 in parapodia of largest segments. Separation between superior and inferior bundles disappears in posterior parapodia, and number of chaetae decreases to less than five or six on posteriormost segments. Posteriormost 4–6 segments of smallest specimens have rudimentary parapodia and no chaetae. Neurochaetae slender, shafts smooth, each with strongly bent distal tooth and longer slender and delicate secondary spine, space between tooth and spine angular (Figs 1 E, 3 F); primary teeth all pointing dorsally (Fig. 3 E). Reproduction. Largest specimens, longer than about 15 mm clearly female with small (ca. 25 µm diameter) oocytes in parapodia and loose in coelom (Fig. 1 F). Several specimens between approximately 11 and 15 mm appear to be immature females. Sex of smaller specimens not determined. Colour. Preserved specimens white. Colour of live animals not known. Methyl Green staining. Glandular staining variable, most pronounced on the larger specimens. Band of speckles occurring behind the mouth and behind the ventral tentacular cirri. Ventrally, anterior 9 or 10 chaetigers with two widely separated, and interrupted, parallel lines of stain. These lines linked in posterior part of each chaetiger by broad transverse band, producing repetitive H-pattern of stain on anterior venter. The transverse band disappears on following chaetigers, and only two broken parallel lines remain. Other staining associated with the parapodia. Ventral staining patch present at base, as vertical line on body just anterior to each parapod, and as vertical patch on its anterior face. Similar, but more sparse speckled areas on posterior face of parapod. Sparse speckles of stain evident on basal part of dorsal cirri and on body dorsal to parapodia; mid-dorsal region unstained. Pygidial lobes surrounding anus stained. Morphometrics. The morphological attributes measured (width, length, number of segments) for A. sociabilis sp. nov. were strongly correlated: width and length (Fig. 4 A), r = 0.957, p<0.0001, n = 14; segments and length (Fig. 4 B), r = 0.894, p<0.0001, n = 17; segments and width (not figured), r = 0.806, p = 0.0002, n = 14. Etymology. The species name sociabilis (L.), disposed to companionship, relates to the tendency for numerous individuals of the new species to live together. Further, it does honour to Roger Bamber, the most sociable of men. Remarks. Hartman & Boss (1965) and Quiroga & Sellanes (2009) referred to all Antonbruunia prostomial appendages as antennae. The two antero-ventral prostomial appendages are here considered to be palps, while the two larger antero-dorsolateral organs are the lateral antennae. This is consistent with their positions on the prostomium in literature associated with Antonbruunidae (Fauchald 1977; Pleijel & Dahlgren 1998; Pleijel 2001 c; Aguado et al. 2013) and putative related families, Pilargidae (Pettibone 1966; Fitzhugh & Wolf 1990; Fauchald & Rouse 1997; Glasby 1993, 2000; Pleijel 2001 b) and Nautiliniellidae (Pleijel 2001 a; Fauchald & Rouse 1997; Aguado & Rouse 2011; Aguado et al. 2013). However, as Glasby (1993) pointed out, the true nature of the anteroventral appendages in Antonbruunia “must remain in doubt until better material is available to conduct histological study.” Antonbruunia sociabilis sp. nov. is morphologically most similar to A. viridis. Segment 1, bearing the tentacular cirri, is well-defined dorsally and laterally as a distinct ring behind the prostomium. The palps and antennae are relatively slender tapering to narrow tips, median antennae and palps of similar size. Both have slender cirriform anal cirri. In A. gerdesi, the tentacular cirri are more anteriorly positioned below/lateral to the prostomium, and segment 1 is dorsally reduced and narrow. All the anterior appendages are more robust, and the median antenna is similar to the lateral antennae in size and shape. The anal cirri are very robust also. Its body form seems altogether wider (Fig. 4 A), though some caution must be exercised here due to potential differences attributable to fixation treatments; A. gerdesi material was removed from its bivalve host and then fixed in 10 % formalin prior to transfer in 70 % ethanol, while A. sociabilis was preserved inside its host when the latter was preserved directly in 70 % ethanol. Antonbruunia viridis was likewise removed live from its host, but fixing and preservation were not reported. Antonbruunia gerdesi and the new species differ from A. viridis in having broad-based conical, rather than slender and cirriform, dorsal cirri. These two species additionally may possess more angular neurochaetae (but see Glasby 1993: fig. 3 b). The new species differs from A. viridis in having three, rather than two (Glasby figures only one), aciculae in median chaetigers. It differs from both A. viridis and A. gerdesi in having more rounded and less protruding ventral cirri in the mid-body region; these two with short pointed ventral cirri throughout. All three species differ in the number of chaetae present. The maximum number of neurochaetae per parapodium reported was 26–30 (Hartman & Boss 1965) for A. viridis; Glasby (1993) depicted 35. For A. gerdesi, the SEM images presented by Quiroga & Sellanes (2009) revealed at least 70 neurochaetae. Antonbruunia sociabilis is intermediate between these two, having up to 50 neurochaetae. The three species are widely separated geographically, occur at different depths and have different host bivalves: Antonbruunia viridis (Western Indian Ocean, 68–82 m, with Lucina fosteri), A. gerdesi (Southeastern Pacific Ocean, 795–846 m, with Calyptogena gallardoi), and A. sociabilis (Northeastern Atlantic, 1187–1200 m, with Thyasira scotiae). The first was reported to occur in male-female pairs in 80 % of more than 100 L. fosteri animals, one bivalve hosted three individuals. The Chilean species was less prevalent with only four of 35 C. gallardoi animals hosting a single individual, although three occurred in another. Calyptogena gallardoi was unusual in additionally hosting the ‘nautiliniellid’ (now part of Calamyzinae in Chrysopetalidae, see Aguado et al. 2013) Shinkai robusta Quiroga & Sellanes, 2009 (single individuals in two of 35 bivalves), but there was no cooccurrence with A. gerdesi. Antonbruunia sociabilis is remarkable in having up to nine individuals inhabiting T. scotiae (maximum recorded size 19.8 x 19.6 x 12.56 mm). It was not obvious whether the three smallest specimens of A. sociabilis were male or simply juvenile. The presence of 4–6 small posterior segments with rudimentary parapodia may be indicative of the latter. It is unusual to have many symbionts living in one bivalve host. In the Thyasiridae, Blake (1990) found only single examples of the calamyzin Petrecca thyasira inhabiting Thyasira insignis (Verrill & Bush, 1898) from the deep Northwestern Atlantic (3720 m). Miura & Hashimoto (1996) similarly found a single individual of Thyasiridicola branchiatus in Conchocele disjuncta Gabb, 1866 from Hatsushima cold seep, Japan (1160 m). However, Aguado & Rouse (2011) recorded up to 25 individuals of Laubierus alvini within the larger (6.0– 10.4 cm) Mytilidae Bathymodiolus sp. from methane seeps off Costa Rica, Eastern Pacific Ocean (1000–1800 m).Published as part of Mackie, Andrew S. Y., Oliver, P. Graham & Nygren, Arne, 2015, Antonbruunia sociabilis sp. nov. (Annelida: Antonbruunidae) associated with the chemosynthetic deep-sea bivalve Thyasira scotiae Oliver & Drewery, 2014, and a re-examination of the systematic affinities of Antonbruunidae in Zootaxa 3995 (1), DOI: 10.11646/zootaxa.3995.1.4, http://zenodo.org/record/24271
Radio Frequency and DC High Voltage Breakdown of High Pressure Helium, Argon, and Xenon
No full text[EN] Motivated by the possibility of guiding daughter ions from double beta decay events to single-ion sensors for barium tagging, the NEXT collaboration is developing a program of R&D to test radio frequency (RF) carpets for ion transport in high pressure xenon gas. This would require carpet functionality in regimes at higher pressures than have been previously reported, implying correspondingly larger electrode voltages than in existing systems. This mode of operation appears plausible for contemporary RF-carpet geometries due to the higher predicted breakdown strength of high pressure xenon relative to low pressure helium, the working medium in most existing RF carpet devices. In this paper we present the first measurements of the high voltage dielectric strength of xenon gas at high pressure and at the relevant RF frequencies for ion transport (in the 10MHz range), as well as new DC and RF measurements of the dielectric strengths of high pressure argon and helium gases at small gap sizes. We find breakdown voltages that are compatible with stable RF carpet operation given the gas, pressure, voltage, materials and geometry of interest.Woodruff, K.; Baeza-Rubio, J.; Huerta, D.; Jones, BJP.; Mcdonald, AD.; Norman, L.; Nygren, DR.... (2020). Radio Frequency and DC High Voltage Breakdown of High Pressure Helium, Argon, and Xenon. Journal of Instrumentation. 15(4):1-15. https://doi.org/10.1088/1748-0221/15/04/P04022S115154Dehmelt, H. G., & Major, F. G. (1962). Orientation of(He4)+Ions by Exchange Collisions with Cesium Atoms. Physical Review Letters, 8(5), 213-214. doi:10.1103/physrevlett.8.213Wada, M., Ishida, Y., Nakamura, T., Yamazaki, Y., Kambara, T., Ohyama, H., … Katayama, I. (2003). Slow RI-beams from projectile fragment separators. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 204, 570-581. doi:10.1016/s0168-583x(02)02151-1Gehring, A. E., Brodeur, M., Bollen, G., Morrissey, D. J., & Schwarz, S. (2016). Research and development of ion surfing RF carpets for the cyclotron gas stopper at the NSCL. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 376, 221-224. doi:10.1016/j.nimb.2016.02.012Ranjan, M., Purushothaman, S., Dickel, T., Geissel, H., Plass, W. R., Schäfer, D., … Dendooven, P. (2011). New stopping cell capabilities: RF carpet performance at high gas density and cryogenic operation. EPL (Europhysics Letters), 96(5), 52001. doi:10.1209/0295-5075/96/52001Arai, F., Ito, Y., Katayama, I., Schury, P., Sonoda, T., Wada, M., & Wollnik, H. (2015). Performance of Ion Surfing Rf-carpets for High-Energy RI Beam Gas Catcher. Proceedings of the Conference on Advances in Radioactive Isotope Science (ARIS2014). doi:10.7566/jpscp.6.030110Schwarz, S. (2011). RF ion carpets: The electric field, the effective potential, operational parameters and an analysis of stability. International Journal of Mass Spectrometry, 299(2-3), 71-77. doi:10.1016/j.ijms.2010.09.021Paschen, F. (1889). Ueber die zum Funkenübergang in Luft, Wasserstoff und Kohlensäure bei verschiedenen Drucken erforderliche Potentialdifferenz. Annalen der Physik, 273(5), 69-96. doi:10.1002/andp.18892730505Jones, F. L., & Morgan, G. D. (1951). High-Frequency Discharges: I Breakdown Mechanism and Similarity Relationship. Proceedings of the Physical Society. 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Physical Review C, 44(3), R931-R934. doi:10.1103/physrevc.44.r931Sinclair, D., Rollin, E., Smith, J., Mommers, A., Ackeran, N., Aharmin, B., … Breidenbach, M. (2011). Prospects for Barium Tagging in Gaseous Xenon. Journal of Physics: Conference Series, 309, 012005. doi:10.1088/1742-6596/309/1/012005Brunner, T., Fudenberg, D., Sabourov, A., Varentsov, V. L., Gratta, G., & Sinclair, D. (2013). A setup for Ba-ion extraction from high pressure Xe gas for double-beta decay studies with EXO. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 317, 473-475. doi:10.1016/j.nimb.2013.05.086Twelker, K., Kravitz, S., Díez, M. M., Gratta, G., Fairbank, W., Albert, J. B., … Benitez-Medina, C. (2014). An apparatus to manipulate and identify individual Ba ions from bulk liquid Xe. Review of Scientific Instruments, 85(9), 095114. doi:10.1063/1.4895646Mong, B., Cook, S., Walton, T., Chambers, C., Craycraft, A., Benitez-Medina, C., … Auty, D. J. (2015). Spectroscopy of Ba andBa+deposits in solid xenon for barium tagging in nEXO. Physical Review A, 91(2). doi:10.1103/physreva.91.022505Brunner, T., Fudenberg, D., Varentsov, V., Sabourov, A., Gratta, G., Dilling, J., … Albert, J. B. (2015). An RF-only ion-funnel for extraction from high-pressure gases. International Journal of Mass Spectrometry, 379, 110-120. doi:10.1016/j.ijms.2015.01.003Nygren, D. R. (2016). Detection of the barium daughter in 136Xe →136Ba+2e− by in situ single-molecule fluorescence imaging. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 824, 2-5. doi:10.1016/j.nima.2015.11.038Jones, B. J. P., McDonald, A. D., & Nygren, D. R. (2016). Single molecule fluorescence imaging as a technique for barium tagging in neutrinoless double beta decay. Journal of Instrumentation, 11(12), P12011-P12011. doi:10.1088/1748-0221/11/12/p12011Byrnes, N., Foss, F. W., Jones, B. J. ., McDonald, A. D., Nygren, D. R., … Thapa, P. (2019). Progress toward Barium Tagging in High Pressure Xenon Gas with Single Molecule Fluorescence Imaging. Journal of Physics: Conference Series, 1312, 012001. doi:10.1088/1742-6596/1312/1/012001McDonald, A. D., Jones, B. J. P., Nygren, D. R., Adams, C., Álvarez, V., Azevedo, C. D. R., … Cárcel, S. (2018). Demonstration of Single-Barium-Ion Sensitivity for Neutrinoless Double-Beta Decay Using Single-Molecule Fluorescence Imaging. Physical Review Letters, 120(13). doi:10.1103/physrevlett.120.132504(2019). Imaging individual barium atoms in solid xenon for barium tagging in nEXO. Nature, 569(7755), 203-207. doi:10.1038/s41586-019-1169-4Thapa, P., Arnquist, I., Byrnes, N., Denisenko, A. A., Foss, F. W., Jones, B. J. P., … Woodruff, K. (2019). Barium Chemosensors with Dry-Phase Fluorescence for Neutrinoless Double Beta Decay. Scientific Reports, 9(1). doi:10.1038/s41598-019-49283-xMartín-Albo, J., Muñoz Vidal, J., Ferrario, P., Nebot-Guinot, M., Gómez-Cadenas, J. J., … Cárcel, S. (2016). Sensitivity of NEXT-100 to neutrinoless double beta decay. Journal of High Energy Physics, 2016(5). doi:10.1007/jhep05(2016)159Bainglass, E., Jones, B. J. P., Foss, F. W., Huda, M. N., & Nygren, D. R. (2018). Mobility and clustering of barium ions and dications in high-pressure xenon gas. Physical Review A, 97(6). doi:10.1103/physreva.97.062509Postel, O. B., & Cappelli, M. A. (2000). Vacuum emission and breakdown characteristics of a planar He–Xe microdischarge. Applied Physics Letters, 76(5), 544-546. doi:10.1063/1.125813Sosov, Y., & Theodosiou, C. E. (2004). Determination of electric field-dependent effective secondary emission coefficients for He/Xe ions on brass. Journal of Applied Physics, 95(8), 4385-4388. doi:10.1063/1.1655677Lieberman, M. A., & Lichtenberg, A. J. (2005). Principles of Plasma Discharges and Materials Processing. doi:10.1002/0471724254Lisovskiy, V. A., Yakovin, S. D., & Yegorenkov, V. D. (2000). Low-pressure gas breakdown in uniform dc electric field. Journal of Physics D: Applied Physics, 33(21), 2722-2730. doi:10.1088/0022-3727/33/21/310Smith, H. B., Charles, C., & Boswell, R. W. (2003). Breakdown behavior in radio-frequency argon discharges. Physics of Plasmas, 10(3), 875-881. doi:10.1063/1.1531615Bhattacharya, A. K. (1976). Measurement of breakdown potentials and Townsend ionization coefficients for the Penning mixtures of neon and xenon. Physical Review A, 13(3), 1219-1225. doi:10.1103/physreva.13.1219Jacques, L., Bruynooghe, W., Boucique, R., & Wieme, W. (1986). Experimental determination of the primary and secondary ionisation coefficients in krypton and xenon. Journal of Physics D: Applied Physics, 19(9), 1731-1739. doi:10.1088/0022-3727/19/9/017Bradford, H. M., Fraser, D. M., Langstroth, G. F. O., & MacDonald, A. D. (1959). ELECTRICAL BREAKDOWN IN XENON AND KRYPTON AT ULTRAHIGH FREQUENCIES. Canadian Journal of Physics, 37(10), 1166-1170. doi:10.1139/p59-133Park, J., Henins, I., Herrmann, H. W., & Selwyn, G. S. (2001). Gas breakdown in an atmospheric pressure radio-frequency capacitive plasma source. Journal of Applied Physics, 89(1), 15-19. doi:10.1063/1.1323754Moravej, M., Yang, X., Nowling, G. R., Chang, J. P., Hicks, R. F., & Babayan, S. E. (2004). Physics of high-pressure helium and argon radio-frequency plasmas. Journal of Applied Physics, 96(12), 7011-7017. doi:10.1063/1.1815047Borg Dezani, V., & Ginoux, J. L. (1994). Investigation of breakdown voltage curves for pure helium and silane–helium mixtures. Physics of Plasmas, 1(4), 1060-1063. doi:10.1063/1.870786McDonald, A. D., Woodruff, K., Atoum, B. A., González-Díaz, D., Jones, B. J. P., Adams, C., … Azevedo, C. D. . (2019). Electron drift and longitudinal diffusion in high pressure xenon-helium gas mixtures. Journal of Instrumentation, 14(08), P08009-P08009. doi:10.1088/1748-0221/14/08/p08009Rogers, L., Clark, R. A., Jones, B. J. P., McDonald, A. D., Nygren, D. R., Psihas, F., … Azevedo, C. D. . (2018). High voltage insulation and gas absorption of polymers in high pressure argon and xenon gases. Journal of Instrumentation, 13(10), P10002-P10002. doi:10.1088/1748-0221/13/10/p10002Okawa, M., Shioiri, T., Okubo, H., & Yanabu, S. (1988). Area effect on electric breakdown of copper and stainless steel electrodes in vacuum. IEEE Transactions on Electrical Insulation, 23(1), 77-81. doi:10.1109/14.2336Kihara, T. (1952). The Mathematical Theory of Electrical Discharges in Gases. Reviews of Modern Physics, 24(1), 45-61. doi:10.1103/revmodphys.24.45Hamaker, A., Brodeur, M., Kelly, J. M., Long, J., Nicoloff, C., Ryan, S., … Wada, M. (2016). Experimental investigation of the repelling force from RF carpets. International Journal of Mass Spectrometry, 404, 14-19. doi:10.1016/j.ijms.2016.04.00
THE PRAIRIE NATURALIST Volume 29, No.3. September 1997
No full textFISHING STATISTICS IN KANSAS PUT-AND-TAKE RAINBOW TROUT FISHERIES ▪ R. D. Schultz and D. D. Nygren
DISTRIBUTIONAL STATUS Of UNCOMMON FISHES AND AN AMPHIBIAN FROM NORTHEASTERN MISSOURI ▪ R. A. Hrabik,
DIET OF A RELICT POPULATION OF THE EASTERN WOODRAT IN NEBRASKA ▪ H. H. Genoways, P. W Freeman, and M. K. Clausen
ANIMAL SPECIES MONITORED BY THE SOUTH DAKOTA NATURAL HERITAGE PROGRAM ▪ E. D. Stukel and D. C. Backlund
Dedication
Announcement
Laonice grimaldii Sikorski, Nygren & Mikac 2021, n. sp.
No full textLaonice grimaldii Sikorski, Nygren & Mikac n. sp. http://zoobank.org:act: D21FC5F2-B9E2-4840-B75F-2D24EBBC2F45 (Figs 10, 11, 12A–C, 13, 14A, 18C, 19B, Table 3) Aonides cirrata: Fauvel, 1909 (Part.): 4–5. Not M. Sars 1851. Laonice cirrata: Fauvel, 1927 (Part.): 37–38, fig. 12a–e. Not M. Sars 1851. Type locality. ITALY, Ligurian Sea, st. GAS 10 ter., 43.6368°N, 10.0983°E, 70–80 m, muddy sand. Type material. MOM INV-0022706 (holotype), INV-0022681–0022693, 0022698, 0022699 (35 paratypes); HUJI NVPOLY-2950 (4 paratypes); MIMB 39037–39039, 39047 (23 paratypes); MNCNM 16.01 /18549–18566 (144 paratypes). Adult morphology. Holotype largest complete specimen 40 mm long, 0.8 mm wide for 109 chaetigers. Smallest complete paratype 13 mm long, 0.26 mm wide for 61 chaetigers. Pigmentation absent on body and palps. Gatherings of glandular cells on branchiae and postchaetal lamellae appearing dark in some formalin-fixed specimens. Prostomium triangular, anteriorly wide, truncate or broadly rounded, fused with anterior margin of peristomium (Figs 10A, B, F, 12A), extending posteriorly to chaetiger 37 (to end of chaetiger 33 in holotype) as a low caruncle (Figs 10A, 12A), shorter in small individuals (Fig. 13A). Posterior end of caruncle flat and often indistinct (Fig. 12B). Nuchal organs U-shaped ciliary bands on sides of caruncle (Fig. 10A). Length of nuchal organs was strongly correlated with individual number of branchiate chaetigers (Fig. 13C, r 2 = 0.8927, n = 30). Occipital antenna present, usually small (Fig. 10A, B, F, 12A). One pair of medium-sized median eyes as transverse short wide bands or oblong oval spots oriented obliquely (Figs 10A, F, 12A). Palps as long as 10–14 chaetigers, with deep frontal longitudinal groove lined with cilia. Chaetiger 1 with short capillaries and moderate sized postchaetal lamellae in both rami. Capillaries in each anterior parapodium arranged in two vertical rows. All notopodia with capillary chaetae only. Notopodial postchaetal lamellae with pointed upper tips usually on 3–4 anterior chaetigers (Fig. 10A), occasionally on 5–9 anterior chaetigers (Fig. 11A–D), with rounded to truncate upper edge on succeeding chaetigers (Fig. 11E, F). Notopodial postchaetal lamellae of chaetiger 3 slightly larger than those of chaetiger 4. Notopodial lamellae and branchiae on anterior chaetigers usually overlapping middorsally, thus obscuring observation of nuchal organs. Notopodial postchaetal lamellae on last branchiate chaetiger and on about seven succeeding postbranchial chaetigers with lower part expanded ventrally (Fig. 11G). Neuropodial postchaetal lamellae until chaetiger 4 with upper part acute (Fig. 11A, B), on succeeding chaetigers with rounded edges (Fig. 11C–G). Branchiae from chaetiger 2 to chaetigers 12–45 (on chaetigers 2–38 in holotype), fewer in smaller individuals (Fig. 13A). Branchiae short on anterior chaetigers, full-sized and slightly longer than notopodial postchaetal lamellae from chaetigers 4–5 onwards (Fig. 11B–F). Individual number of branchiae was strongly correlated with length of nuchal organs (Fig. 13C). Dorsal transverse crests absent on chaetigers with nuchal organs (Fig. 12B). Two dorsal crests usually present on each of 2–3 last branchiate chaetigers (Fig. 10D). Anterior crest on each of those chaetigers appearing as an extension of posterior sides of lateral interneuropodial pouches onto dorsum (Fig. 10C, D), becoming prominent from chaetiger 16 (Fig. 10C) and forming complete dorsal crests on 3–4 last branchiate chaetigers (Fig. 10D). Posterior crests appearing 1–2 chaetigers after first start of anterior crests and interconnecting notopodial postchaetal lamellae (Fig. 10D). Anterior and posterior crests almost equal in maximum height on 2–3 last branchiate chaetigers. Anterior crests reduced in height on succeeding chaetigers and disappearing completely after 2–6 postbranchiate chaetigers. Posterior crests on approximately 20 postbranchiate chaetigers (until chaetiger 57 in holotype) becoming nearly as high as notopodial postchaetal lamellae. Lateral interneuropodial pouches from chaetigers 7–26 (from chaetiger 14 in holotype) to body end. Anterior start of pouches was moderately correlated with individual number of branchiate chaetigers (Fig. 18C, r 2 = 0.5278, n = 29). Sabre chaetae in neuropodia from chaetigers 8–18 (from chaetiger 15 in holotype), from more anterior chaetigers in smaller individuals (Fig. 13B), 1–2 in a tuft below vertical row of capillaries or hooded hooks (Fig. 11F, G). Anterior start of sabre chaetae was weakly correlated with individual number of branchiate chaetigers (Fig. 13D, r 2 = 0.2854, n = 30). Hooded hooks in neuropodia from chaetigers 13–36 (from chaetiger 34 in holotype), from more anterior chaetigers in smaller individuals (Fig. 13B), up to 13 in a series (Fig. 11G). Hooks tri- or quinquedentate, with one or two pairs of small apical teeth above main fang (Figs 11H, 12C); superior pair of teeth tiny and hardly discernible, not developed in some hooks. Anterior start of hooks was strongly correlated with individual number of branchiate chaetigers (Fig. 13D, r 2 = 0.9189, n = 31). Pygidium with one pair of short ventral cirri and up to four pairs of longer and thinner thread-like dorsal cirri with swollen bases (Fig. 10E). Digestive tract without gizzard-like structure. Methylene green staining. Intensely stained narrow band along frontal edge of prostomium and peristomium (Fig. 10F); usually stained as well the posterior surfaces, lateral margins and sometimes frontal surfaces of distal parts of notopodial postchaetal lamellae from chaetiger 4 to chaetiger 9 (rarely up to chaetiger 19), and basal parts of pygidial cirri (Fig. 10F). Characteristic diffused staining on ventral body surface, most intensely from approximately chaetiger 21 to chaetigers 33–35 (Fig. 10G). Remarks. Adult L. grimaldii n. sp. appear similar to L. bahusiensis in having the prostomium fused with the frontal margin of the peristomium, dorsal crests only on postbranchiate chaetigers and a narrow band along the frontal edge of prostomium stained with Methylene Green. They differ from all other species of Laonice in having double dorsal crests on chaetigers near the last branchiate chaetiger. Within the L. bahusiensis complex, L. grimaldii n. sp. differs from the other species in having rounded instead of acute notopodial postchaetal lamellae after chaetigers 4–9, and branchiae being slightly longer instead of considerably longer (from 1.3 to 2 times longer) than notopodial postchaetal lamellae. Moreover, the adults of L. grimaldii n. sp. characteristically have a caruncle flattened and therefore indistinct on its posterior end (Fig. 12B), contrary to adults of most other species, which have distinct caruncles that terminate clearly and abruptly. The adults of L. grimaldii n. sp. are similar to those of L. antipoda Sikorski, 2011 from South Africa in various numeric characteristics, especially in the presence of branchiae and prominent dorsal crests on several chaetigers posterior to nuchal organs. In the original description of L. antipoda, Sikorski (2011) noticed the absence of an occipital antenna in the specimens examined but assumed that it might be due to damage. Recent examinations of additional material of L. antipoda from Angola and Gabon (Sikorski, unpublished), however, confirmed the lack of an occipital antenna in this species (Fig. 12D). Thus, L. grimaldii n. sp. differs from L. antipoda by having smaller adults (maximum body width ≤ 0.8 mm in L. grimaldii n. sp. versus ≥ 1.0 mm in L. antipoda), double dorsal crests on 1–2 last branchiate chaetiger(s), an occipital antenna on the prostomium, and notopodial postchaetal lamellae of chaetiger 4 smaller than those of chaetiger 3 (instead of much bigger as in L. antipoda). Etymology. The name of the species refers to the House of Grimaldi, the princely family of Monaco and, more specifically, it is dedicated to Prince Albert I, who collected some of the specimens used for the present species description. Distribution. Mediterranean Sea (Fig. 14A). At 4–80 m depth.Published as part of Sikorski, Andrey V., Radashevsky, Vasily I., Castelli, Alberto, Pavlova, Lyudmila V., Nygren, Arne, Malyar, Vasily V., Borisova, Polina B., Mikac, Barbara, Rousou, Maria, Martin, Daniel, Gil, João, Pacciardi, Lorenzo & Langeneck, Joachim, 2021, Revision of the Laonice bahusiensis complex (Annelida: Spionidae) with a description of three new species, pp. 253-283 in Zootaxa 4996 (2) on pages 269-273, DOI: 10.11646/zootaxa.4996.2.2, http://zenodo.org/record/506982
Impact of climate variability on dynamic groundwater storage in mid- to high latitude countries
No full textClimate change will alter the hydrological cycle, potentially changing dynamic groundwater
storage and increasing groundwater drought risk. Climate influences groundwater storage
directly via changes in groundwater recharge, but groundwater drought responsiveness further
depends on groundwater system characteristics. The aim of this thesis is to increase our
understanding of how climate variability and groundwater system characteristics influence
groundwater storage, in mid- and high latitude countries.
To address this aim, groundwater, precipitation and temperature data from Sweden and Finland
between 1980 and 2010 was evaluated. Different hydroclimate regimes were compared to
seasonal and inter-annual groundwater level fluctuations. Furthermore, the influence of
groundwater system characteristics on groundwater drought responsiveness was assessed by
analysing precipitation and groundwater level anomalies from Sweden, Finland and the Lower
Fraser Valley (Canada). Correlation analysis between groundwater drought responsiveness and
selected environmental properties was applied on Swedish data.
The main findings of this thesis are, first, that between 1980 and 2010, groundwater recharge
became decreasingly driven by snowmelt in spring. Instead, recharge became increasingly
influenced by winter rain and high evapotranspiration rates in spring. As a result, dynamic
groundwater storage significantly decreased across the region, particularly in Finland. Second,
inter-annual groundwater level trends, covering the same period, did not correspond to trends
of increasing winter snowmelt and rainfall. Groundwater level trends instead showed stronger
similarity to trends in wet days, i.e. frequency of days with precipitation. Furthermore,
groundwater trends corresponded better to trends in the frost-free season, compared to trends
found in the frost season. Third, variability in groundwater drought responsiveness could be
partly explained by environmental properties, such as sediment type (sand, silt and till),
groundwater level depth, climate and atmospheric teleconnections.
These findings suggest that within this century, annual groundwater recharge will decrease in
the study areas, due to the projected increase in temperature and precipitation. However, this
also depends on the effect of decreased ground frost on winter infiltration, and the balance
between precipitation and evapotranspiration. Finally, the need for a holistic approach in
groundwater drought characterisation is made apparent by the influence of climate and
atmospheric teleconnections on groundwater drought responsiveness
Journalism: a profession under pressure?
No full textThis article explores how the changing nature of journalistic work and organization are affecting the profession, the way it is perceived by personnel, the roles played by journalists, and autonomy of journalists. It finds that the technical and economic changes are disrupting the established professional status, roles, and practices of journalists, removing professional control that previously existed
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