366 research outputs found
The influence of binarity on the morpho-kinematics of planetary nebulae
The role of central star binarity in the shaping of planetary nebulae (PNe)
has been the subject of much debate, with single stars believed to be incapable
of producing the most highly collimated morphologies. However, observational
support for binary-induced shaping has been sadly lacking. Here, we highlight
the results of a continuing programme to spatio-kinematically model the
morphologies of all PNe known to contain a close binary central star.
Spatio-kinematical modelling is imperative for these objects, as it circumvents
the degeneracy between morphology and orientation which can adversely affect
determinations of morphology based on imaging alone. Furthermore,
spatio-kinematical modelling accurately determines the orientation of the
nebular shell, allowing the theoretically predicted perpendicular alignment,
between nebular symmetry axis and binary orbital plane, to be tested. To date,
every PN subjected to this investigation has displayed the predicted alignment,
indicating that binarity has played an important role in the formation and
evolution of these nebulae. The further results from this programme will be
key, not only in determining whether binary interaction is responsible for
shaping the studied PNe, but also in assessing the importance of binarity in
the formation and evolution of all PNe in general.Comment: 2 pages, 2 tables, proceedings of the IAU Symposium No. 283,
Planetary Nebulae: An Eye to the Futur
A study of the kinematics and binary-induced shaping of the planetary nebula HaTr 4
We present the first detailed spatio-kinematical analysis and modelling of
the planetary nebula HaTr 4, one of few known to contain a post-common-envelope
central star system. Common envelope evolution is believed to play an important
role in the shaping of planetary nebulae, but the exact nature of this role is
yet to be understood. High spatial- and spectral- resolution spectroscopy of
the [OIII]5007 nebular line obtained with VLT-UVES are presented alongside deep
narrowband Ha+[NII]6584 imagery obtained using EMMI-NTT, and together the two
are used to derive the three-dimensional morphology of HaTr 4. The nebula is
found to display an extended ovoid morphology with an enhanced equatorial
region consistent with a toroidal waist - a feature believed to be typical
amongst planetary nebulae with post-common-envelope central stars. The nebular
symmetry axis is found to lie perpendicular to the orbital plane of the central
binary, concordant with the idea that the formation and evolution of HaTr 4 has
been strongly influenced by its central binary.Comment: 9 pages, 5 figures, accepted for publication in MNRA
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Sustainability of collaborative care management for depression in primary care settings with academic affiliations across New York State
Background
In a large statewide initiative, New York State implemented collaborative care (CC) from 2012 to 2014 in 32 primary care settings where residents were trained and supported its sustainability through payment reforms implemented in 2015. Twenty-six clinics entered the sustainability phase and six opted out, providing an opportunity to examine factors predicting continued CC participation and fidelity.
Methods
We used descriptive statistics to assess implementation metrics in sustaining vs. opt-out clinics and trends in implementation fidelity 1 and 2Â years into the sustainability phase among sustaining clinics. To characterize barriers and facilitators, we conducted 31 semi-structured interviews with psychiatrists, clinic administrators, primary care physicians, and depression care managers (24 at sustaining, 7 at opt-out clinics).
Results
At the end of the implementation phase, clinics opting to continue the program had significantly higher care manager full-time equivalents (FTEs) and achieved greater clinical improvement rates (46% vs. 7.5%, p = 0.004) than opt-out clinics. At 1 and 2 years into sustainability, the 26 sustaining clinics had steady rates of depression screening, staffing FTEs and treatment titration rates, significantly higher contacts/patient and improvement rates and fewer enrolled patients/FTE.
During the sustainability phase, opt-out sites reported lower patient caseloads/FTE, psychiatry and care manager FTEs, and physician/psychiatrist CC involvement compared to sustaining clinics. Key barriers to sustainability noted by respondents included time/resources/personnel (71% of respondents from sustaining clinics vs. 86% from opt-out), patient engagement (67% vs. 43%), and staff/provider engagement (50% vs. 43%). Fewer respondents mentioned early implementation barriers such as leadership support, training, finance, and screening/referral logistics. Facilitators included engaging patients (e.g., warm handoffs) (79% vs. 86%) and staff/providers (71% vs. 100%), and hiring personnel (75% vs. 57%), particularly paraprofessionals for administrative tasks (67% vs. 0%).
Conclusions
Clinics that saw early clinical improvement and who invested in staffing FTEs were more likely to elect to enter the sustainability phase. Structural rules (e.g., payment reform) both encouraged participation in the sustainability phase and boosted long-term outcomes. While limited to settings with academic affiliations, these results demonstrate that patient and provider engagement and care manager resources are critical factors to ensuring sustainability
Cellular location and activity of Escherichia coli RecG proteins shed light on the function of its structurally unresolved C-terminus
RecG is a DNA translocase encoded by most species of bacteria. The Escherichia coli protein targets branched DNA substrates and drives the unwinding and rewinding of DNA strands. Its ability to remodel replication forks and to genetically interact with PriA protein have led to the idea that it plays an important role in securing faithful genome duplication. Here we report that RecG co-localises with sites of DNA replication and identify conserved arginine and tryptophan residues near its C-terminus that are needed for this localisation. We establish that the extreme C-terminus, which is not resolved in the crystal structure, is vital for DNA unwinding but not for DNA binding. Substituting an alanine for a highly conserved tyrosine near the very end results in a substantial reduction in the ability to unwind replication fork and Holliday junction structures but has no effect on substrate affinity. Deleting or substituting the terminal alanine causes an even greater reduction in unwinding activity, which is somewhat surprising as this residue is not uniformly present in closely related RecG proteins. More significantly, the extreme C-terminal mutations have little effect on localisation. Mutations that do prevent localisation result in only a slight reduction in the capacity for DNA repair. © 2014 The Author(s)
RE: How the Coronavirus Disease-2019 May Improve Care: Rethinking Cervical Cancer Prevention
Feldman and Haas have written a timely piece on the potential to enhance cancer prevention and cancer care delivery in the COVID-19 era. Using cervical cancer prevention as a use case, the commentary describes clinical care provided via virtual platforms and in nontraditional settings, such as the patient’s home, as areas needing creative approaches to ensure care is provided safely and efficiently. As we consider factors that are relevant to delivering effective cancer prevention and cancer care post-COVID, we suggest that addressing social determinants of health, an often forgotten dimension of lived experience, should be prioritized as a strategy to enhance the equity of care provision. Social determinants of health, including food and housing insecurity have been shown to impact outcomes of patients with cancer, through a number of mechanisms including delays and incomplete care
Nuclear Envelope Composition Determines The Ability Of Neutrophil-Type Cells To Passage Through Micron-Scale Constrictions
Neutrophils are characterized by their distinct nuclear shape, which is thought to facilitate the transit of these cells through pore spaces less than one-fifth of their diameter. We used human promyelocytic leukemia (HL-60) cells as a model system to investigate the effect of nuclear shape in whole cell deformability. We probed neutrophil-differentiated HL-60 cells lacking expression of lamin B receptor, which fail to develop lobulated nuclei during granulopoiesis and present an in vitro model for Pelger-Huët anomaly; despite the circular morphology of their nuclei, the cells passed through micron-scale constrictions on similar timescales as scrambled controls. We then investigated the unique nuclear envelope composition of neutrophil-differentiated HL-60 cells, which may also impact their deformability; although lamin A is typically down-regulated during granulopoiesis, we genetically modified HL-60 cells to generate a subpopulation of cells with well defined levels of ectopic lamin A. The lamin A-overexpressing neutrophil-type cells showed similar functional characteristics as the mock controls, but they had an impaired ability to pass through micron-scale constrictions. Our results suggest that levels of lamin A have a marked effect on the ability of neutrophils to passage through micron-scale constrictions, whereas the unusual multilobed shape of the neutrophil nucleus is less essential
Development and immunogenicity of a prototype multivalent Group B Streptococcus bioconjugate vaccine
Group
Structural studies suggest aggregation as one of the modes of action for teixobactin
Teixobactin is a new promising antibiotic that targets cell wall biosynthesis by binding to lipid II and has no detectable resistance thanks to its unique but yet not fully understood mechanism of operation. To aid in the structure-based design of teixobactin analogues with improved pharmacological properties, we present a 3D structure of native teixobactin in membrane mimetics and characterise its binding to lipid II through a combination of solution NMR and fast (90 kHz) magic angle spinning solid state NMR. In NMR titrations, we observe a pattern strongly suggesting interactions between the backbone of the C-terminal “cage” and the pyrophosphate moiety in lipid II. We find that the N-terminal part of teixobactin does not only act as a membrane anchor, as previously thought, but is actively involved in binding. Moreover, teixobactin forms a well-structured and specific complex with lipid II, where the N-terminal part of teixobactin assumes a b conformation that is highly prone to aggregation, which likely contributes to the antibiotic's high bactericidal efficiency. Overall, our study provides several new clues to teixobactin's modes of action
Measuring organisational readiness for patient engagement (MORE) : an international online Delphi consensus study
Date of Acceptance: 28/01/2015. © 2015 Oostendorp et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise statedWidespread implementation of patient engagement by organisations and clinical teams is not a reality yet. The aim of this study is to develop a measure of organisational readiness for patient engagement designed to monitor and facilitate a healthcare organisation’s willingness and ability to effectively implement patient engagement in healthcarePeer reviewedFinal Published versio
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