200,910 research outputs found
δ Orionis: Further temporal variability and evidence for small-scale structure in the interstellar medium
No full textWe report here the detection of both spatial and temporal variations in interstellar absorption in the line of sight to δ Orionis. First, we present new high-resolution (R≈110 000) observations of the interstellar D lines of Na i towards both δ Ori A and C. Comparison of these spectra highlights variations in absorption between the two stars, indicative of small-scale spatial structure in the interstellar medium in this direction over distances of less than ≈15 000 au (the projected separation of the two stars). Components with the largest Na i column densities and lowest velocity dispersions are, in general, found to be subject to the greatest differences; in fact the narrowest component detected is only observed in one of the sightlines. This effect has also been reported by Meyer & Blades. Secondly, we present new ultra-high-resolution (R≈900 000) Na i D1 observations and high-resolution (R≈110 000) Ca ii H & K observations of δ Ori A which, through ultra-high-resolution work conducted between 1994 and 2000, has been shown to exhibit a time-variable interstellar Na i absorption component. These new observations, while revealing the further reduction in intensity of the time-variable Na i absorption, indicate constant Ca ii absorption over the same period. This results in a dramatic reduction in the Na°/Ca+ abundance ratio, perhaps indicating the line of sight to be gradually probing a less-dense outer region of an absorbing filament
Impinging Howarth stagnation-point flows
No full textThe flow of one Howarth stagnation-point flow impinging directly on another Howarth stagnation-point flow is studied, and an exact similarity solution to the Navier-Stokes equations is found. The upper layer fluid has density ρ1 and kinematic viscosity ʋ1 while the lower layer fluid has density ρ2 and kinematic viscosity ʋ2 and the two fluids are assumed to be immiscible. This problem has potentially five independent parameters to investigate, but application of the continuity of the normal stresses at the interface imposes restrictions which reduces the problem to one with three independent parameters, namely a ratio σ of strain rates and the fluid parameter ratios ρ = ρ1/ρ2 and ʋ = ʋ1/ʋ2. Numerical results are presented for selected values of ρ and ʋ for a range of σ and show that stable results exist for all values of σ > 0, and for a range of negative σ values. Sample stable velocity profiles are also presented
Axisymmetric form of Kármán-Howarth equation and its limiting forms
No full textInternational audienceKinematics and dynamics of homogeneous axisymmetric turbulence have been derived with the assumption that the properties of the turbulence are invariant with respect to rotation about a preferred direction λ. In particular, the "axisymmetric" equivalent of Karman-Howarth "isotropic" equation is derived using Lindborg's representation of the two-point correlation tensors of homogeneous axisymmetric turbulence. When the more constraining assumption of isotropy is made, this equation reduces to the well-known Karman-Howarth equation. There are two interesting limiting forms of the axisymmetric Karman-Howarth equation: the axisymmetric form of the energy balance equation and the axisymmetric form of the vorticity balance equation
The processing of antigens delivered as DNA vaccines
No full textThe ability of DNA vaccines to provide effective immunological protection against infection and tumors depends on their ability to generate good CD4+ and CD8+ T-cell responses. Priming of these responses is a property of dendritic cells (DCs), and so the efficacy of DNA-encoded vaccines is likely to depend on the way in which the antigens they encode are processed by DCs. This processing could either be via the synthesis of the vaccine-encoded antigen by the DCs themselves or via its uptake by DCs following its synthesis in bystander cells that are unable to prime T cells. These different sources of antigen are likely to engage different antigen-processing pathways, which are the subject of this review. Understanding how to access different processing pathways in DCs may ultimately aid the rational development of plasmid-based vaccines to pathogens and to cancer
Athamanthia balucha subsp. balucha Howarth & Povolny 1976
No full textAthamanthia balucha balucha (Howarth & Povolny, 1976) (Plate 1, figs. 1–4; plate 2, fig. 2) Lycaena athamantis balucha — Howarth & Povolny 1976: 150. Lycaena phoenicurus balucha Howarth & Povolny, 1976 — Nekrutenko 1984: 47. Athamanthia balucha (Howarth & Povolny, 1976) — Bozano & Weidenhoffer 2001: 41. Type locality. Baluchistan, Old Urak, 27.VI. [19]28 [Pakistan, Balochistan Prov., 10 km NEE Quetta, Urak valley]. Material examined. Holotype ♂, Baluchistan, Old Urak, 27.VI.1928 (photo examined); paratypes: 1 ♀, same locality as in the holotype, 10.VI.1928 (photo examined); 1 ♂, Baluchistan: Urak, 26.V.1929 (photo and genitalia drawing from Nekrutenko (1984) examined), all W.H. Evans leg. (BMNH). Diagnosis. Orange submarginal band of wings upperside strongly reduced in both sexes, only 2–3 spots developed near tornal lobe (band usually well developed in A. phoenicura); thin silvery line extends from tornus midway along to outer margin (line poorly developed near tornal lobe in A. phoenicura); inner black strokes of submarginal orange band of wings underside reduced on both wings (well developed in A. phoenicura); valva widened, with rounded apex and developed inner fold (valva narrowed with indented apex and smaller inner fold in A. phoenicura); aedeagus strongly curved, crescent (aedeagus slightly curved in A. phoenicura). PLATE 1. Athamanthia spp., imagoes: 1— A. balucha balucha (Howarth & Povolny, 1976), holotype, ♂, Baluchistan, Old Urak, 27.VI.1928 (BMNH), photo from (Bozano & Weidenhoffer 2001), upperside; 2— Id., underside; 3— A. b. balucha, paratype, ♀, same locality as in the holotype, 10.VI.1928 (BMNH), photo from (Bozano & Weidenhoffer 2001), upperside; 4— Id., underside; 5— A. b. povolnyi (Howarth & Povolony, 1976), comb. nov., ♂, Central Afghanistan, Province Bamyan, Bamyan district, 4 km SE Sabzak vill., 34°51'48" N, 67°41'13" E, 2700 m, 09.VII.2013, I.G. Pljushtch leg. (SIZK), upperside; 6— Id., underside; 7— A. b. povolnyi (Howarth & Povolony, 1976), comb. nov., ♀, Central Afghanistan, Province Bamyan, Bamyan district, 4 km SE Sabzak vill., 34°51'48" N, 67°41'13" E, 2700 m, 09.VII.2013, I.G. Pljushtch leg., (SIZK), upperside; 8— Id., underside; 9— A. b. athamantides (Eckweiler & ten Hagen, 2001), comb. nov., ♂, South Eastern Iran, Kerman Province, 20 km SE Makhan, 2450 m, 19.VI.2014, I.G. Pljushtch leg., gen. prep. AK0068 (AKM), upperside; 10— Id., underside; 11— A. b. povolnyi (Howarth & Povolony, 1976), comb. nov., holotype, ♂, East Afghanistan, Province Kabul, Sarobi, 12.IV. [19]65, leg. Povolny (MMB), upperside; 12— Id., underside; 13— A. b. povolnyi (Howarth & Povolony, 1976), comb. nov., labels of the holotype; 14— A. phoenicura (Lederer, 1871), ♂, Turkmenistan, W Kopet Dagh Mts., Aydere gorge, 13.VI.1985, A.L. Devyatkin leg. (AKM), upperside; 15— Id., underside; 16— A. phoenicura (Lederer, 1871), ♂, Turkmenistan, W Kopet Dagh Mts., Aydere gorge, 13.VI.1985, A.L. Devyatkin leg. (AKM), upperside; 17— Id., underside. PLATE 2. Athamanthia spp., male genitalia (genital capsule in ventral view, valvae in lateral view from inside, aedeagus in lateral view): 1— A. phoenicura (Lederer, 1871), Turkmenistan, W Kopet Dagh Mts., Aydere gorge, 13.VI.1985, A.L. Devyatkin leg., gen. prep. AK0064 (AKM); 2— A. balucha balucha (Howarth & Povolony, 1976), paratype, Baluchistan: Urak, 26.V.1929, original illustration from Nekrutenko (1984); 3— A. balucha povolnyi (Howarth and Povolony, 1976), comb. nov., Central Afghanistan, Province Bamyan, Bamyan district, 0.5 km SE Sabzak vill., 34°52'41" N, 67°39'14" E, 2790 m, 08– 09.VII.2013, Yu. Ye. Skrylnik leg., gen. prep. AK0067 (AKM); 4— A. balucha athamantides (Eckweiler & ten Hagen, 2001), comb. nov., South Eastern Iran, Kerman Province, 20 km SE Makhan, 2450 m, 19.VI.2014, I.G. Pljushtch leg., gen. prep. AK0068 (AKM). Letters indicate on diagnostic characters (see Diagnosis part): a—shape of apex of valva; b—size of inner fold of valva; c—shape of aedeagus.Published as part of Krupitsky, Anatoly V., Pljushtch, Igor G. & Skrylnik, Yuriy Ye., 2017, Systematic position of two Athamanthia Zhdanko, 1983 (Lepidoptera, Lycaenidae) taxa from the Iranian Plateau, pp. 575-581 in Zootaxa 4232 (4) on pages 576-578, DOI: 10.11646/zootaxa.4232.4.7, http://zenodo.org/record/31328
Josephiella Matsunaga & Howarth & Kumashiro 2019, n. sp.
No full text<i>Josephiella</i> n. sp. A (apparently undescribed) <p> <b>NEW STATE RECORD</b></p> <p> An agaonid wasp new to science was discovered causing galls on the stems of <i>Ficus microcarpa</i>. Terminal stems of affected trees appeared unhealthy with a sparse foliar canopy. Initial observers of this damage were under the assumption that the same species which causes leaf galling on <i>F. microcarpa</i> (<i>Josephiella microcarpae</i>) was also causing the galling on stems of the same plant. However, closer examination of the stem-galling wasps showed that while both the leaf-galler and the stem-galler are morphologically similar in many ways, this in fact may be a different species. Both leaf and stem-gallers can be found on the same plant. Jean-Yves Rasplus, co-author of the leaf-galling <i>J. microcarpae</i>, agreed that this could be an undescribed species and is currently working on its species description.</p> <p> Subsequent to the initial discovery of this stem-galler on Oahu in 2012, infested <i>F. microcarpa</i> were quickly noted on Hawaii and Maui. In May, 2016, galled <i>F. microcarpa</i> stems with exit holes were collected from Molokai and in July, 2017, from Kauai. However, material from these islands were too old and no adults could be recovered. Therefore, we do not list the collection data below, and in the list of new species we noted a question mark next to these islands until the adults are confirmed. <i>Josephiella</i> n. sp. A, along with <i>Josephiella microcarpae</i>, lobate lac scale (<i>Paratarchardina pseudolobata</i>), and other ficus-feeding species has contributed to the weakening of large banyan trees on Oahu.</p> <p> <b>Collection records: OAHU</b>, Manoa, 13.VII.2012, ex. <i>Ficus microcarpa</i> stems, coll. D. Hulbert, det. J.-Y. Rasplus, 6.X.2012.</p> <p> <b>HAWAII</b>, Hilo, 30.VII.2012, ex. <i>F. microcarpa</i> stems, coll. C. Hirayama, L. Larish & S. Chun, det. B. Kumashiro, VIII.2012.</p> <p> <b>MAUI</b>, Wailuku, 6.VIII.2012, ex. <i>F. microcarpa</i> stems, coll. M. Fukada, VIII.2012. Vouchers at HDOA.</p>Published as part of <i>Matsunaga, Janis N., Howarth, Francis G. & Kumashiro, Bernarr R., 2019, New State Records and Additions to the Alien Terrestrial Arthropod Fauna in the Hawaiian Islands, pp. 1-71 in Proceedings of the Hawaiian Entomological Society 51 (1)</i> on pages 11-12, DOI: <a href="http://zenodo.org/record/10832895">10.5281/zenodo.10832895</a>
Erratum: Correction:Antibiotic use for Australian Aboriginal children in three remote Northern Territory communities (PloS one (2020) 15 4 (e0231798))
No full textThere is an error in affiliation 1 for authors Timothy Howarth and Therese M. Kearns, in affiliation 4 for author Ross M. Andrews, and in affiliation 7 for author Federica Barzi. The correct
affiliation 1 is: Child Health, Menzies School of Health Research, Charles Darwin University,
Darwin, Northern Territory, Australia. The correct affiliation 4 is: Tropical Health, Menzies
School of Health Research, Charles Darwin University, Brisbane, Queensland, Australia. The
correct affiliation 7 is: Wellbeing and Preventable Chronic Diseases, Menzies School of Health
Research, Charles Darwin University, Darwin, Northern Territory, Australia
A new look at the pathogenesis of asthma
No full textAsthma is an inflammatory disorder of the conducting airways that has strong association with allergic sensitization. The disease is characterized by a polarized Th-2 (T-helper-2)-type T-cell response, but in general targeting this component of the disease with selective therapies has been disappointing and most therapy still relies on bronchodilators and corticosteroids rather than treating underlying disease mechanisms. With the disappointing outcomes of targeting individual Th-2 cytokines or manipulating T-cells, the time has come to re-evaluate the direction of research in this disease. A case is made that asthma has its origins in the airways themselves involving defective structural and functional behaviour of the epithelium in relation to environmental insults. Specifically, a defect in barrier function and an impaired innate immune response to viral infection may provide the substrate upon which allergic sensitization takes place. Once sensitized, the repeated allergen exposure will lead to disease persistence. These mechanisms could also be used to explain airway wall remodelling and the susceptibility of the asthmatic lung to exacerbations provoked by respiratory viruses, air pollution episodes and exposure to biologically active allergens. Variable activation of this epithelial-mesenchymal trophic unit could also lead to the emergence of different asthma phenotypes and a more targeted approach to the treatment of these. It also raises the possibility of developing treatments that increase the lung's resistance to the inhaled environment rather than concentrating all efforts on trying to suppress inflammation once it has become established.<br/
- …
