735 research outputs found
The Evolution of Women\u27s Education
The author discusses the history of women\u27s education, focusing on the time periods of ancient Mesopotamia, the Victorian era, and the early half of the twentieth century
The Global Asteroseismology Project Proof of Concept: Asteroseismology of Massive Stars with Continuous Ground-Based Observations
Massive (>~ 8 solar masses) stars are the progenitors of many astrophysical
systems, yet key aspects of their structure and evolution are poorly
understood. Asteroseismology has the potential to solve these open puzzles,
however, sampling both the short period pulsations and long period beat
patterns of massive stars poses many observational challenges. Ground-based
single-site observations require years or decades to discern the main
oscillation modes. Multi-site campaigns were able to shorten this time span,
but have not been able to scale up to population studies on samples of objects.
Space-based observations can achieve both continuous sampling and observe large
numbers of objects, however, most lack the multi-band data that is often
necessary for mode identification and removing model degeneracies. Here, we
develop and test a new ground-based observational strategy for discerning and
identifying the main oscillation modes of a massive star in a few months, in a
way that can be scaled to large samples. We do so using the Las Cumbres
Observatory - a unique facility consisting of robotic, homogeneous telescopes
operating as a global network, overcoming most of the challenges of previous
multi-site efforts, but presenting new challenges which we tailor our strategy
to address. This work serves as the proof of concept for the Global
Asteroseismology Project, which aims to move massive star asteroseismology from
single-objects to bulk studies, unleashing its full potential in constraining
stellar structure and evolution models. This work also demonstrates the ability
of the Las Cumbres Observatory to perform multi-site continuous observations
for various science goals.Comment: Accepted for publication in A
SoccerNet 2023 Tracking Challenge -- 3rd place MOT4MOT Team Technical Report
The SoccerNet 2023 tracking challenge requires the detection and tracking of
soccer players and the ball. In this work, we present our approach to tackle
these tasks separately. We employ a state-of-the-art online multi-object
tracker and a contemporary object detector for player tracking. To overcome the
limitations of our online approach, we incorporate a post-processing stage
using interpolation and appearance-free track merging. Additionally, an
appearance-based track merging technique is used to handle the termination and
creation of tracks far from the image boundaries. Ball tracking is formulated
as single object detection, and a fine-tuned YOLOv8l detector with proprietary
filtering improves the detection precision. Our method achieves 3rd place on
the SoccerNet 2023 tracking challenge with a HOTA score of 66.27.Comment: 3 pages, 1 figur
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Draft genome of Rosenbergiella nectarea strain 8N4T provides insights into the potential role of this species in its plant host.
Background:Rosenbergiella nectarea strain 8N4T, the type species of the genus Rosenbergiella, was isolated from Amygdalus communis (almond) floral nectar. Other strains of this species were isolated from the floral nectar of Citrus paradisi (grapefruit), Nicotiana glauca (tobacco tree) and from Asphodelus aestivus. R. nectarea strain 8N4T is a Gram-negative, oxidase-negative, facultatively anaerobic bacterium in the family Enterobacteriaceae. Results:Here we describe features of this organism, together with its genome sequence and annotation. The DNA GC content is 47.38%, the assembly size is 3,294,717 bp, and the total number of genes are 3,346. The genome discloses the possible role that this species may play in the plant. The genome contains both virulence genes, like pectin lyase and hemolysin, that may harm plant cells and genes that are predicted to produce volatile compounds that may impact the visitation rates by nectar consumers, such as pollinators and nectar thieves. Conclusions:The genome of R. nectarea strain 8N4T reveals a mutualistic interaction with the plant host and a possible effect on plant pollination and fitness
Clinical and radiological features of Mycobacterium kansasii and other NTM infections
SummaryBackgroundMycobacterium kansasii infection is one of the most common causes of nontuberculous mycobacterial lung disease in the world. However, it is not possible to differentiate completely between M. kansasii and other nontuberculous mycobacteria (NTM) because of a lack of direct comparative studies. This retrospective study sought to identify their clinical and radiological features systematically.MethodsThe sample included 98 consecutive patients with a culture-positive diagnosis of NTM infection, derived from the databases of the Laboratory of Microbiology of a tertiary medical center and two outpatient tuberculosis centers. Sixty-four patients had M. kansasii infection. All patients fulfilled disease criteria for treatment. Data on patient background and clinical features were collected, and chest radiographs were evaluated.ResultsIn the M. kansasii group, n = 27 (42%) were native-born Israelis compared to 9.4% (n = 3) of all other NTM groups (p = 0.0001). Similar rates of co-morbid diseases, including diabetes mellitus, heart disease, lung diseases, and malignancy were noted in both groups. Old TB was less common in the M. kansasii group compared to the other NTM (3.1% vs. 23.5%, p = 0.003). Clinical symptoms were significantly more common in patients with M. kansasii infection. On radiological study, M. kansasii infection was associated with more cavitations and unilaterality. Patients with M. kansasii infection had a higher likelihood of right upper lobe disease (p = 0.001). Pleural effusions and lymphadenopathy were found only in a few patients in each group.ConclusionMajor differences in the epidemiologic and clinical features of M. kansasii infection and other NTM have important diagnostic and clinical implications
Weak Measurements of Light Chirality with a Plasmonic Slit
We examine, both experimentally and theoretically, an interaction of tightly
focused polarized light with a slit on a metal surface supporting
plasmon-polariton modes. Remarkably, this simple system can be highly sensitive
to the polarization of the incident light and offers a perfect
quantum-weak-measurement tool with a built-in post-selection in the
plasmon-polariton mode. We observe the plasmonic spin Hall effect in both
coordinate and momentum spaces which is interpreted as weak measurements of the
helicity of light with real and imaginary weak values determined by the input
polarization. Our experiment combines advantages of (i) quantum weak
measurements, (ii) near-field plasmonic systems, and (iii) high-numerical
aperture microscopy in employing spin-orbit interaction of light and probing
light chirality.Comment: 5 pages, 3 figure
Successful lung transplantation for talcosis secondary to intravenous abuse of oral drug
Talcosis due to intravenous injection of oral drugs can cause severe pulmonary disease with progressive dyspnea even when drug use is discontinued. We describe a 54-year-old woman with severe emphysema who underwent left lung transplantation. The patient had a remote history of intravenous injection of crushed methylphenidate (Ritalin) tablets. Chest computed tomography showed severe emphysematous changes, more prominent in the lower lobes. Microscopic examination of the extracted lung demonstrated multinucleated giant cells with birefringent crystals, compatible with talcosis. At follow-up, daily symptoms were completely alleviated and lung function was good. We recommend that lung transplantation be considered as a viable option in the treatment of talcosis
Asymmetric Free-Space Light Transport at Nonlinear Metasurfaces
Asymmetric light transport has significantly contributed to fundamental science and revolutionized advanced technology in various aspects such as unidirectional photonic devices, optical diodes, and isolators. While metasurfaces mold wave fronts at will with an ultrathin flat optical element, asymmetric transport of light cannot be fundamentally achieved by any linear system including linear metasurfaces. We report asymmetric transport of free-space light at nonlinear metasurfaces upon transmission and reflection. Moreover, we theoretically derive the nonlinear generalized Snell\u27s laws that were experimentally confirmed by the anomalous nonlinear refraction and reflection. The asymmetric transport at optically thin nonlinear interfaces is revealed by the concept of a reversed propagation path. Such an asymmetric transport at metasurfaces opens a new paradigm for free-space ultrathin lightweight optical devices with one-way operation including unrivaled optical valves and diodes
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