1,602 research outputs found
4,4′,6,6′-TetraÂbromo-2,2′-(2,8-diazonia-5-azanona-1,8-diene-1,9-diyl)diphenolate
In the zwitterionic title compound, C18H17Br4N3O2, the two salicylaldimine groups form a dihedral angle of 51.94 (2)° and the dihedral angle between the aromatic ring planes is 51.14 (2)°. One of the C atoms adjacent to the aza N atom is disordered over two positions; the site-occupancy factors are 0.51 (1) and 0.49 (1). There are two strong intraÂmolecular N—H⋯O hydrogen bonds in the molÂecule
Exploring Anisotropic Lorentz Invariance Violation from the Spectral-Lag Transitions of Gamma-Ray Bursts
The observed spectral lags of gamma-ray bursts (GRBs) have been widely used
to explore possible violations of Lorentz invariance. However, these studies
were generally performed by concentrating on the rough time lag of a single
highest-energy photon and ignoring the intrinsic time lag at the source. A new
way to test nonbirefringent Lorentz-violating effects has been proposed by
analyzing the multi-photon spectral-lag behavior of a GRB that displays a
positive-to-negative transition. This method gives both a plausible description
of the intrinsic energy-dependent time lag and comparatively robust constraints
on Lorentz-violating effects. In this work, we conduct a systematic search for
Lorentz-violating photon dispersion from the spectral-lag transition features
of 32 GRBs. By fitting the spectral-lag data of these 32 GRBs, we place
constraints on a variety of isotropic and anisotropic Lorentz-violating
coefficients with mass dimension and . While our dispersion
constraints are not competitive with existing bounds, they have the promise to
complement the full coefficient space.Comment: 17 pages, 2 figures, 2 tables. Published by Universe. Constribution
to the Special Issue "Advances in Astrophysics and Cosmology-in Memory of
Prof. Tan Lu
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Optimizing Survivorship Care Services for Asian Adolescent and Young Adult Cancer Survivors: A Qualitative Study.
Purpose: With an increasing focus on developing survivorship services tailored for adolescent and young adult (AYA) cancer survivors, incorporation of viewpoints from both survivors and health care professionals (HCPs) is important. This study aims to explore the perceptions of current and prospective survivorship services from both groups in Singapore to propose service design and delivery strategies. Methods: Focus group discussions with 23 AYA cancer survivors between the ages of 16 and 39 years at diagnosis and 18 HCPs were conducted in National Cancer Centre Singapore (NCCS) and Singapore Cancer Society (SCS). All focus group discussions were transcribed verbatim. Deductive thematic analysis was performed according to the components of a design thinking model: empathizing with AYA survivors, defining care gaps, proposing services, and implementation strategies. Results: AYA survivors preferred age-specific services that are aligned with their personal goals. Current survivorship care failed to address the needs of survivors' dependents (caregivers and children) and to consider the utility of each service temporally. Prospective services should clarify disease disclosure obligation in job search and introduce a care navigator. Key implementation strategies included (1) training HCPs on communication techniques with AYA, (2) selecting engagement platforms that complement survivors' information-seeking behavior, (3) improving outreach to survivors through appropriate branding and publicity, and (4) consolidating services from multiple providers. Conclusions: The design of survivorship care services for AYA survivors should be systematic in its conceptualization process and employ implementation strategies. The coordination of the wide spectrum of services warrants a concerted effort by cancer centers, community partners, and the government
Surgical management of 142 cases of split cord malformations associated with osseous divide
Objectives
To investigate the key surgical points in treating split cord malformations associated with osseous divide and scoliosis (SCM-OD-S).
Materials and methods
The surgical options and methods of a total of 142 SCM-OD-S cases were retrospectively analyzed, and the surgical precautions and imaging diagnosis were also discussed.
Results
The 142 patients were performed osseous divide resection plus dural sac molding, which achieved good results and no serious complication such as spinal cord and nerve injury occurred; certain symptoms such as urination-defecation disorders, muscle strength subsidence, Pes Cavus, and toe movement disorder in partial patients achieved various degrees of relief, and it also created good conditions for next-step treatment against scoliosis.
Conclusions
The diagnosis of SCM-OD mainly depended on imaging inspection, routine magnetic resonance imaging (MRI) combined with computed tomography (CT) 3D reconstruction, which can comprehensively evaluate the types and features of diastematomyelia as well as other concomitant diseases. SCM alone needed no treatment, but surgery will be the only means of treating SCM-OD. Intraoperatively removing osseous divide step-by-step, as well as carefully freeing the spinal cord and remodeling the dural sac, can lay good foundations for relieving tethered cord, improving neurological symptoms, and further scoliosis orthomorphia, thus particularly exhibiting importance for the growth and development of adolescents
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