110 research outputs found

    The Sky is Falling… Or is it?

    Get PDF
    There are two sides to the issue of societal acceptance of advanced/urban air mobility when it comes to mental health. One is that of the pilots’ mental health, and a topic for another day. The other is that of society’s mental health, the topic of this paper. More specifically, this research seeks to uncover what causes society the most angst when it comes to these operations. Literature review shows that stress increases with noise levels of aircraft flying overhead, as well as vehicle safety. Furthermore, for passengers, the stress caused by fear of flying may be compounded when a pilot is not onboard, as will be the case with these autonomous vehicles. Thus, is it the noise, the safety, or other concerns? The researchers have attempted a qualitative review by surveying a random section of the population in the United States to uncover what causes people stress with advanced/urban air mobility. The findings show that vehicle safety is the main concern, cited by almost ninety percent of respondents

    Von Balthasar y el giro estético de la exégesis veterotestamentaria: Un caso de estudio. Poder y alianza en la transición de Saúl a David

    Full text link

    SU(3) Symmetry and Scissors Mode Vibrations in Nuclei

    Full text link
    We show that a nearly perfect SU(3) symmetry emerges from an extended Projected Shell Model. Starting from a deformed potential we construct separate bases for neutron and proton collective rotational states by exact angular momentum projection. These rotational states are then coupled by diagonalizing a residual pairing plus quadrupole interaction. The states obtained exhibit a one-to-one correspondence with an SU(3) spectrum up to high angular momentum and excitation, and their wave functions have a near-maximal overlap with the SU(3) states. They can also be classified as rotational bands built on spin-1\hbar phonon excitations, which may correspond to a geometrical scissors mode and its generalizations. This work is a direct demonstration that numerical angular momentum projection theory extends the Elliott's original idea to heavy nuclear systems.Comment: 25 pages, 4 eps figures, final version accepted by Nucl. Phys.

    Multi-Phonon γ\gamma-Vibrational Bands and the Triaxial Projected Shell Model

    Full text link
    We present a fully quantum-mechanical, microscopic, unified treatment of ground-state band and multi-phonon γ\gamma-vibrational bands using shell model diagonalization with the triaxial projected shell model. The results agree very well with data on the g- and γ\gamma-band spectra in 156170^{156-170}Er, as well as with recently measured 4+4^+ 2-phonon γ\gamma-bandhead energies in 166^{166}Er and 168^{168}Er. Multi-phonon γ\gamma-excitation energies are predicted.Comment: 4 pages, 4 figures, submitted to Phys. Lett.

    Improving quality of experience in adaptive low latency live streaming

    Get PDF
    HTTP Adaptive Streaming (HAS), the most prominent technology for streaming video over the Internet, suffers from high end-to-end latency when compared to conventional broadcast methods. This latency is caused by the content being delivered as segments rather than as a continuous stream, requiring the client to buffer significant amounts of data to provide resilience to variations in network throughput and enable continuous playout of content without stalling. The client uses an Adaptive Bitrate (ABR) algorithm to select the quality at which to request each segment to trade-off video quality with the avoidance of stalling to improve the Quality of Experience (QoE). The speed at which the ABR algorithm responds to changes in network conditions influences the amount of data that needs to be buffered, and hence to achieve low latency the ABR needs to respond quickly. Llama (Lyko et al. 28) is a new low latency ABR algorithm that we have previously proposed and assessed against four on-demand ABR algorithms. In this article, we report an evaluation of Llama that demonstrates its suitability for low latency streaming and compares its performance against three state-of-the-art low latency ABR algorithms across multiple QoE metrics and in various network scenarios. Additionally, we report an extensive subjective test to assess the impact of variations in video quality on QoE, where the variations are derived from ABR behaviour observed in the evaluation, using short segments and scenarios. We publish our subjective testing results in full and make our throughput traces available to the research community

    Dissemination of Spotted Fever Rickettsia Agents in Europe by Migrating Birds

    Get PDF
    Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp.IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases

    Antibody response following the third and fourth SARS-CoV-2 vaccine dose in individuals with common variable immunodeficiency

    Get PDF
    BackgroundThe antibody response after vaccination is impaired in common variable immunodeficiency (CVID).ObjectiveWe aimed to study the spike receptor-binding domain IgG antibody (anti-S-RBD) levels during a four-dose SARS-CoV-2 vaccination strategy and after monoclonal antibody (mAB) treatment in CVID. Moreover, we assessed the anti-S-RBD levels in immunoglobulin replacement therapy (IgRT) products.MethodsIn an observational study, we examined anti-S-RBD levels after the second, third, and fourth dose of mRNA SARS-CoV-2 vaccines. Moreover, we measured anti-S-RBD after treatment with mAB. Finally, anti-S-RBD was assessed in common IgRT products. Antibody non-responders (anti-S-RBD < 7.1) were compared by McNemar’s test and anti-S-RBD levels were compared with paired and non-paired Wilcoxon signed rank tests as well as Kruskal–Wallis tests.ResultsAmong 33 individuals with CVID, anti-S-RBD levels increased after the third vaccine dose (165 BAU/ml [95% confidence interval: 85; 2280 BAU/ml], p = 0.006) and tended to increase after the fourth dose (193 BAU/ml, [−22; 569 BAU/ml], p = 0.080) compared to the previous dose. With increasing number of vaccinations, the proportion of patients who seroconverted (anti-S-RBD ≥ 7.1) increased non-significantly. mAB treatment resulted in a large increase in anti-S-RBD and a higher median level than gained after the fourth dose of vaccine (p = 0.009). IgRT products had varying concentrations of anti-S-RBD (p < 0.001), but none of the products seemed to affect the overall antibody levels (p = 0.460).ConclusionMultiple SARS-CoV-2 vaccine doses in CVID seem to provide additional protection, as antibody levels increased after the third and fourth vaccine dose. However, anti-S-RBD levels from mAB outperform the levels mounted after vaccination.Clinical ImplicationsBoosting with SARS-CoV-2 vaccines seems to improve the antibody response in CVID patients.Capsule summaryThe third and possibly also the fourth dose of mRNA SARS-CoV-2 vaccine in CVID improve the antibody response as well as stimulate seroconversion in most non-responders

    Single-Particle and Collective Motion for Proton-Rich Nuclei on the Astrophysical rp-Process Path

    Get PDF
    Based on available experimental data, a new set of Nilsson parameters is proposed for proton-rich nuclei with proton or neutron numbers 28N4028\leq N\leq 40. The resulting single-particle spectra are compared with those from relativistic and non-relativistic mean field theories. Collective excitations in some even--even proton-rich nuclei in the upper pfpf shell are investigated using the Projected Shell Model with the new Nilsson basis. It is found that the regular bands are sharply disturbed by band crossings involving 1g9/21g_{9/2} neutrons and protons. Physical quantities for exploring the nature of the band disturbance and the role of the 1g9/21g_{9/2} single-particle are predicted, which may be tested by new experiments with radioactive beams.Comment: 4 pages, 3 figures, accepted by Phys. Rev. C, Rapid Communicatio

    Integrated Genomic Analysis Implicates Haploinsufficiency of Multiple Chromosome 5q31.2 Genes in De Novo Myelodysplastic Syndromes Pathogenesis

    Get PDF
    Deletions spanning chromosome 5q31.2 are among the most common recurring cytogenetic abnormalities detectable in myelodysplastic syndromes (MDS). Prior genomic studies have suggested that haploinsufficiency of multiple 5q31.2 genes may contribute to MDS pathogenesis. However, this hypothesis has never been formally tested. Therefore, we designed this study to systematically and comprehensively evaluate all 28 chromosome 5q31.2 genes and directly test whether haploinsufficiency of a single 5q31.2 gene may result from a heterozygous nucleotide mutation or microdeletion. We selected paired tumor (bone marrow) and germline (skin) DNA samples from 46 de novo MDS patients (37 without a cytogenetic 5q31.2 deletion) and performed total exonic gene resequencing (479 amplicons) and array comparative genomic hybridization (CGH). We found no somatic nucleotide changes in the 46 MDS samples, and no cytogenetically silent 5q31.2 deletions in 20/20 samples analyzed by array CGH. Twelve novel single nucleotide polymorphisms were discovered. The mRNA levels of 7 genes in the commonly deleted interval were reduced by 50% in CD34+ cells from del(5q) MDS samples, and no gene showed complete loss of expression. Taken together, these data show that small deletions and/or point mutations in individual 5q31.2 genes are not common events in MDS, and implicate haploinsufficiency of multiple genes as the relevant genetic consequence of this common deletion
    corecore