Stall Inception in a Boundary Layer Ingesting Fan

Jet engines with boundary layer ingestion (BLI) could offer significant reductions in aircraft fuel burn compared with podded turbofans. However, the engine fans must run continuously with severe inlet distortion, which is known to reduce stability. In this paper, an experimental study has been completed on a low-speed rig fan operating with a BLI-type inlet distortion. Unsteady casing static pressure measurements have been made at multiple locations during stall events. Steady-state, full-annulus area traverses have also been performed at rotor inlet and exit at a near-stall operating point. The reduction in stability caused by BLI is found to be small. It is found that with BLI the fan can operate stably despite the presence of localized regions where the rotor operating point lies beyond the stability boundary measured in clean flow. With the BLI-type distortion applied, the measured rotor incidence varies around the annulus due to nonuniform upstream velocity and swirl. The measured amplitude of unsteady casing pressure fluctuations just prior to stall is found to correlate with the circumferential variation of rotor incidence, suggesting that rotor incidence is a key variable affecting the creation and growth of flow disturbances. In regions of high incidence, disturbances resembling local flow separations are initiated. However, in regions of low or negative incidence, any disturbances decay rapidly. Full rotating stall with BLI occurs when high incidence regions are widespread enough to sustain disturbances which can propagate around the entire annulus.</jats:p

Novel phylogenetic algorithm to monitor human tropism in Egyptian H5N1-HPAIV reveals evolution toward efficient human-to-human transmission

Years of endemic infections with highly pathogenic avian influenza (HPAI) A subtype H5N1 virus in poultry and high numbers of infections in humans provide ample opportunity in Egypt for H5N1-HPAIV to develop pandemic potential. In an effort to better understand the viral determinants that facilitate human infections of the Egyptian H5N1-HPAIVvirus, we developed a new phylogenetic algorithm based on a new distance measure derived from the informational spectrum method (ISM). This new approach, which describes functional aspects of the evolution of the hemagglutinin subunit 1 (HA1), revealed a growing group G2 of H5N1-HPAIV in Egypt after 2009 that acquired new informational spectrum (IS) properties suggestive of an increased human tropism and pandemic potential. While in 2006 all viruses in Egypt belonged to the G1 group, by 2011 these viruses were virtually replaced by G2 viruses. All of the G2 viruses displayed four characteristic mutations (D43N, S120(D,N), (S,L)129Δ and I151T), three of which were previously reported to increase binding to the human receptor. Already in 2006–2008 G2 viruses were significantly (p<0.02) more often found in humans than expected from their overall prevalence and this further increased in 2009–2011 (p<0.007). Our approach also identified viruses that acquired additional mutations that we predict to further enhance their human tropism. The extensive evolution of Egyptian H5N1-HPAIV towards a preferential human tropism underlines an urgent need to closely monitor these viruses with respect to molecular determinants of virulence

Comprehension of novel metaphor in young children with Developmental Language Disorder

BACKGROUND AND AIMS: Difficulties with aspects of morphosyntax, phonology and/or vocabulary are the hallmark of Development Language Disorder (DLD). Yet, little is known about the linguistic-pragmatic abilities of young children with DLD. Previous studies suggest that children with DLD are experiencing difficulties with idioms, sayings and slang expressions, often interpreting them in a literal or unconventional fashion. However, it is unclear whether this is caused by difficulties to make pragmatic inferences in general or whether it stems from their semantic abilities. We therefore investigated novel metaphor understanding in young children with and without DLD. METHODS: We assessed novel metaphor comprehension using a reference assignment task with 15 children with DLD diagnoses (ages 42–49 months) as well as typically developing peers matched on chronological age (n = 15) and on language (n = 15). RESULTS: Children with DLD performed worse than their age-matched peers but in a comparable manner to the (younger) language-matched typically developing children. Performance was not related to non-verbal intelligence in the children with DLD. CONCLUSION: The findings indicate that young children with DLD have difficulties with metaphor comprehension but also suggest that these difficulties are in line with their general language difficulties and linked to their overall linguistic competence rather than reflecting additional specific issues with deriving pragmatic inferences. IMPLICATIONS: Our study adds to a growing body of literature showing that children with low language abilities are also likely to display more difficulties in understanding figurative language independently of any other symptomatology of their clinical diagnosis. It also supports the argument that deficits in the pragmatic domain are a secondary impairment rather than a core deficit in children with DLD. Nonetheless, children with DLD do show difficulties in understanding metaphors. Understanding figurative language is necessary for everyday communication and should therefore be targeted alongside traditional treatments by clinicians treating children with DLD

Life cycle and host range of Phycitasp. rejected for biological control of prickly acacia in Australia

Prickly acacia (Vachellia nilotica subsp. indica), a native of the Indian subcontinent, is a serious weed of the grazing areas of northern Australia and is a target for classical biological control. Native range surveys in India identified a leaf webber, Phycita sp. (Lepidoptera: Pyralidae) as a prospective biological control agent for prickly acacia. In this study, we report the life cycle and host-specificity test results Phycita sp. and highlight the contradictory results between the no-choice tests in India and Australia and the field host range in India. In no-choice tests in India and Australia, Phycita sp. completed development on two of 11 and 16 of 27 non-target test plant species, respectively. Although Phycita sp. fed and completed development on two non-target test plant species (Vachellia planifrons and V. leucophloea) in no-choice tests in India, there was no evidence of the insect on the two non-target test plant species in the field. Our contention is that oviposition behaviour could be the key mechanism in host selection of Phycita sp., resulting in its incidence only on prickly acacia in India. This is supported by paired oviposition choice tests involving three test plant species (Acacia baileyana, A. mearnsii and A. deanei) in quarantine in Australia, where eggs were laid only on prickly acacia. However, in paired oviposition choice trials, only few eggs were laid, making the results unreliable. Although oviposition choice tests suggest that prickly acacia is the most preferred and natural host, difficulties in conducting choice oviposition tests with fully grown trees under quarantine conditions in Australia and the logistic difficulties of conducting open-field tests with fully grown native Australian plants in India have led to rejection of Phycita sp. as a potential biological control agent for prickly acacia in Australia

Kartierung der Zwergrostresistenz der Gerste MBR1012

Zusammenfassung Der Zwergrost gehört zu den wichtigsten Krankheitserregern der Gerste und kann im gemäßigten Klima Ertragsverluste von über 60 % verursachen. Auf der Suche nach neuen Resistenzquellen wurde in der aus Serbien-Montenegro stammenden Landrasse MBR1012 eine wirksame Resistenz gegenüber Zwergrost identifiziert. Um die Vererbung der Resistenz dieser Landrasse aufzuklären, wurden 76 DH-Linien aus der Kreuzung der resistenten Landrasse MBR1012 mit der anfälligen Sorte Scarlett mit der hochvirulenten Zwergrostrasse I80 künstlich inokuliert. Die Spaltung der DH-Population nach der Inokulation mit I80 zeigte, dass die Resistenz monogenetisch vererbt wird. Basierend auf den Ergebnissen der bulked segregant analysis konnte die Resistenz dem Chromosom 1H zugeordnet werden und eng gekoppelte molekulare Marker entwickelt werden, welche eine beschleunigte Übertragung dieser Resistenz in adaptierte Sorten erlauben. Die Suche nach neuen Resistenzen gegen Puccinia hordei ist von besonderer Bedeutung, da die Rostpilze durch Mutation und Rekombination zahlreiche physiologische Rassen bilden, wodurch Resistenzen relativ schnell überwunden werden können. Stichwörter: Gerste (Hordeum vulgare L.), Zwergrost (Puccinia hordei Otth), Resistenz, bulked segregant analysis (BSA), DH-Linien (doubled-haploid).   Abstract Leaf rust (Puccinia hordei Otth) is an economically important disease of barley in temperate regions, causing considerable yield losses up to about 60 %. Resistance to leaf rust has been detected in a landrace derived from Serbia Montenegro (MBR1012). To obtain information on the genetics of resistance of MBR1012 to leaf rust, 76 DH-lines derived from a cross of MBR1012 to the susceptible cv. Scarlett were inoculated using the highly virulent leaf rust isolate I80. It turned out that resistance is inherited in a monogenic manner and by bulked segregant analysis resistance was assigned to chromosome 1H. Next closely linked molecular markers were developed facilitating an efficient introgression into adapted cultivars. Broadening the genetic base of resistance to leaf rust is of special importance as this pathogen is able to overcome resistances quickly due to mutation and recombination. Keywords: Barley (Hordeum vulgare L.), leaf rust (Puccinia hordei Otth), resistance, bulked segregant analysis (BSA), DH-lines (doubled-haploid

Time-dependent reduction of structural complexity of the buccal epithelial cell nuclei after treatment with silver nanoparticles

Recent studies have suggested that silver nanoparticles (AgNPs) may affect cell DNA structure in in vitro conditions. In this paper, we present the results indicating that AgNPs change nuclear complexity properties in isolated human epithelial buccal cells in a time-dependent manner. Epithelial buccal cells were plated in special tissue culture chamber / slides and were kept at 37°C in an RPMI 1640 cell culture medium supplemented with L-glutamine. The cells were treated with colloidal silver nanoparticles suspended in RPMI 1640 medium at the concentration 15 mg L−1. Digital micrographs of the cell nuclei in a sample of 30 cells were created at five different time steps: before the treatment (controls), immediately after the treatment, as well as 15 , 30 and 60 min after the treatment with AgNPs. For each nuclear structure, values of fractal dimension, lacunarity, circularity, as well as parameters of grey level co-occurrence matrix (GLCM) texture, were determined. The results indicate time-dependent reduction of structural complexity in the cell nuclei after the contact with AgNPs. These findings further suggest that AgNPs, at concentrations present in today's over-the-counter drug products, might have significant effects on the cell genetic material

The consensus rye microsatellite map with EST-SSRs transferred from wheat

Microsatellite (SSR) markers with known precise intrachromosomal locations are widely used for mapping genes in rye and for the investigation of wheat-rye translocation lines and triticale highly demanded for mapping economically important genes and QTL-analysis. One of the sources of novel SSR markers in rye are microsatellites transferable from the wheat genome. Broadening the list of available SSRs in rye mapped to chromosomes is still needed, since some rye chromosome maps still have just a few microsatellite loci mapped. The goal of the current study was to integrate wheat EST-SSRs into the existing rye genetic maps and to construct a consensus rye microsatellite map. Four rye mapping populations (P87/P105, N6/N2, N7/N2 and N7/N6) were tested with CFE (EST-SSRs) primers. A total of 23 Xcfe loci were mapped on rye chromosomes: Xcfe023, -136 and -266 on chromosome 1R, Xcfe006, -067, -175 and -187 on 2R, Xcfe029 and -282 on 3R, Xcfe004, -100, -152, -224 and -260 on 4R, Xcfe037, -208 and -270 on 5R, Xcfe124, -159 and -277 on 6R, Xcfe010, -143 and -228 on 7R. With the exception of Xcfe159 and Xcfe224, all the Xcfe loci mapped were found in orthologous positions considering multiple evolutionary translocations in the rye genome relative to those of common wheat. The consensus map was constructed using mapping data from the four bi-parental populations. It contains a total of 123 microsatellites, 12 SNPs, 118 RFLPs and 2 isozyme loci

Matrix-assisted laser desorption/ionization time of flight mass spectrometry identification of Vibrio (Listonella) anguillarum isolated from sea bass and sea bream

Vibrio (Listonella) anguillarum is a pathogenic bacterium causing septicaemia in a wide range of marine organisms and inducing severe mortalities, thus it is crucial to conduct its accurate and rapid identification. The aim of this study was to assess MALDI-TOF MS as a method of choice for identification of clinical V. anguillarum isolates from affected marine fish. Since the method accuracy might be influenced by the type of the medium used, as well as by the incubation conditions, we tested V. anguillarum isolates grown on standard media with and without the addition of NaCl, cultured at three incubation temperatures, and at three incubation periods. The best scores were retrieved for V. anguillarum strains grown on NaCl-supplemented tryptone soy agar (TSA) at 22°C and incubated for 48h (100% identification to species level; overall score 2.232), followed by incubation at 37°C and 48h (100% to species level; score 2.192). The strains grown on non-supplemented TSA gave the best readings when incubated at 22°C for 72h (100% identification to species level; overall score 2.182), followed by incubation at 15°C for 72h (100% to species level; score 2.160). Unreliable identifications and no-identifications were growing with the incubation duration at 37°C, on both media, amounting to 88.89% for 7d incubation on supplemented TSA, and 92.60% for 7d incubation on non-supplemented TSA. The age of the cultured strains and use of media significantly impacted the mass spectra, demonstrating that for reliable identification, MALDI-TOF MS protein fingerprinting with the on-target extraction should be performed on strains grown on a NaCl-supplemented medium at temperatures between 15 and 22°C, incubated for 48-72 hours