956 research outputs found
U-Pn geochronology of deformed metagranites in central Sutherland, Scotland: evidence for widespread late Silurian metamorphism and ductile deformation of the Moine Supergroup during the Caledonian orogeny
Within the Caledonides of central Sutherland, Scotland, the Neoproterozoic metasedimentary rocks of the Moine Supergroup record NW-directed D2 ductile thrusting and nappe assembly, accompanied by widespread tight-to-isoclinal folding and amphibolite-facies metamorphism. A series of metagranite sheets which were emplaced and penetratively deformed during D2 have been dated using SHRIMP UĆ¢Pb geochronology. Zircon ages of 424 8 Ma (Vagastie Bridge granite), 420 6 Ma (Klibreck granite) and 429 11 Ma (Strathnaver granite) are interpreted to date emplacement, and hence regional D2 deformation, during
mid- to late Silurian time. Titanite ages of 413 3 Ma (Vagastie Bridge granite) and 416 3 Ma (Klibreck granite) are thought to date post-metamorphic cooling through a blocking temperature of c. 550Ć¢ 500 8C. A mid- to late Silurian age for D2 deformation supports published models that have viewed the internal ductile thrusts of this part of the orogen as part of the same kinematically linked system of forelandpropagating thrusts as the marginal Moine Thrust Zone. The new data contrast with previous interpretations that have viewed the dominant structures and metamorphic assemblages within the Moine Supergroup as having formed during the early to mid-Ordovician Grampian arcĆ¢continent orogeny. The mid-to late Silurian D2 nappe stacking event in Sutherland is probably a result of the collision of Baltica with the Scottish segment of Laurentia
Healthcare risk waste and waste legislation in South Africa
Published ArticleHealthcare risk waste is highly regulated in several countries by well-developed legislative frameworks; however, there is a lack of
development and adherence to directives and laws in developing countries such as South Africa. Although legislation is in place, it does
not always address medical waste in detail to assist with issues such as segregation, categorisation, collection, transport, treatment
and final disposal practices. Incineration is still the most common means of treatment, which has shifted the focus of the Department of
Environmental Affairs, the department responsible for overseeing waste disposal, to air quality monitoring. The objective of this paper is to
highlight issues related to HCRW management, and to suggest a way forward, rather than to provide an in-depth analysis of the problem
Daytime symptoms of chronic obstructive pulmonary disease:a systematic review
There is no single source of compiled data on symptoms experienced by patients with chronic obstructive pulmonary disease (COPD) when awake and active throughout the day. The aim of this systematic review was to evaluate the prevalence, variability, and burden (i.e., bothersomeness and/or intensity), and the impact of daytime COPD symptoms on other outcomes. The review also evaluated the impact of interventions and the measures/tools used to assess daytime COPD symptoms in patients. A systematic literature search was conducted using the primary search terms "COPD", "symptoms", and "daytime" in EMBASEĀ®, MEDLINEĀ®, MEDLINEĀ® In-Process, and CENTRAL in 2016, followed by an additional search in 2018 to capture any new literature that was published since the last search. Fifty-six articles were included in the review. The accumulated evidence indicated that the symptomatic burden of COPD appears greatest in the morning, particularly upon waking, and that these morning symptoms have a substantial impact on patients' ability to function normally through the day; they also worsen quality of life. A wide variety of tools were used to evaluate symptoms across the studies. The literature also confirmed the importance of pharmacotherapy in the management of daytime COPD symptoms, and in helping normalize daily functioning. More research is needed to better understand how COPD symptoms impact daily functioning and to evaluate COPD symptoms at well-defined periods throughout the day, using validated and uniform measures/tools. This will help clinicians to better define patients' needs and take appropriate action
Targeting exertional breathlessness to improve physical activity:the role of primary care
Primary care physicians (PCPs) play a crucial role in the diagnosis and management of chronic obstructive pulmonary disease (COPD). By working together with patients to target exertional breathlessness and increase physical activity, PCPs have an important role to play, early in the disease course, in improving patient outcomes in both the short and long term. In this article, we consider how physical activity affects disease progression from the PCP perspective. We discuss the role of pharmacological therapy, the importance of an holistic approach and the role of PCPs in assessing and promoting physical activity. The complexity and heterogeneity of COPD make it a challenging disease to treat. Patientsā avoidance of activity, and subsequent decline in capacity to perform it, further impacts the management of the disease. Improving patient tolerance of physical activity, increasing participation in daily activities and helping patients to remain active are clear goals of COPD management. These may require an holistic approach to management, including pulmonary rehabilitation and psychological programmes in parallel with bronchodilation therapy, in order to address both physiological and behavioural factors. PCPs have an important role to optimise therapy, set goals and communicate the importance of maintaining physical activity to their patients. In addition, optimal treatment that addresses activity-related breathlessness can help prevent the downward spiral of inactivity and get patients moving again, to improve their overall health and long-term prognosis
Use of electronic medical records and biomarkers to manage risk and resource efficiencies
Peer reviewedPublisher PD
Symmetry-Breaking Motility
Locomotion of bacteria by actin polymerization, and in vitro motion of
spherical beads coated with a protein catalyzing polymerization, are examples
of active motility. Starting from a simple model of forces locally normal to
the surface of a bead, we construct a phenomenological equation for its motion.
The singularities at a continuous transition between moving and stationary
beads are shown to be related to the symmetries of its shape. Universal
features of the phase behavior are calculated analytically and confirmed by
simulations. Fluctuations in velocity are shown to be generically
non-Maxwellian and correlated to the shape of the bead.Comment: 4 pages, 2 figures, REVTeX; formatting of references correcte
Tracing tumorigenesis in a solid tumor model at single-cell resolution
Characterizing the complex composition of solid tumors is fundamental for understanding tumor initiation, progression and metastasis. While patient-derived samples provide valuable insight, they are heterogeneous on multiple molecular levels, and often originate from advanced tumor stages. Here, we use single-cell transcriptome and epitope profiling together with pathway and lineage analyses to study tumorigenesis from a developmental perspective in a mouse model of salivary gland squamous cell carcinoma. We provide a comprehensive cell atlas and characterize tumor-specific cells. We find that these cells are connected along a reproducible developmental trajectory: initiated in basal cells exhibiting an epithelial-to-mesenchymal transition signature, tumorigenesis proceeds through Wnt-differential cancer stem cell-like subpopulations before differentiating into luminal-like cells. Our work provides unbiased insights into tumor-specific cellular identities in a whole tissue environment, and emphasizes the power of using defined genetic model systems
Structure and Strength of Dislocation Junctions: An Atomic Level Analysis
The quasicontinuum method is used to simulate three-dimensional
Lomer-Cottrell junctions both in the absence and in the presence of an applied
stress. The simulations show that this type of junction is destroyed by an
unzipping mechanism in which the dislocations that form the junction are
gradually pulled apart along the junction segment. The calculated critical
stress needed for breaking the junction is comparable to that predicted by line
tension models. The simulations also demonstrate a strong influence of the
initial dislocation line directions on the breaking mechanism, an effect that
is neglected in the macroscopic treatment of the hardening effect of junctions.Comment: 4 pages, 3 figure
Personalized medication adherence management in asthma and COPD:a review of effective interventions and development of a practical adherence toolkit
BACKGROUND: Medication non-adherence management of patients with asthma/COPD remains challenging. Given the multitude of underlying causes, a personalized approach is required. The Test of Adherence to Inhalers (TAI) can identify reasons for non-adherence, but does not provide guidance on how to effectively act on results. OBJECTIVE: To develop a practical, evidence-based decision support toolkit for healthcare professionals managing adult patients with asthma and/or COPD, by matching TAI-identified adherence barriers to proven effective adherence enhancing interventions. METHODS: A literature review in PubMed and Embase was performed identifying interventions that enhanced medication adherence in adult patients with asthma and/or COPD. Randomised controlled trials (RCTs) published in English with full-texts available were included. Effective interventions were assessed by the Cochrane risk of bias tool, categorized, matched with specific TAI responses and developed into a practical TAI Toolkit. The Toolkit was assessed on content and usability (System Usability Scale, SUS) by a multidisciplinary group of healthcare professionals. RESULTS: Forty RCTs were included in the review. In total, seven effective interventions catergories were identified, informing the TAI Toolkit: reminders, educational interventions, motivational strategies, feedback on medication use, shared decision making, simplifying medication regimen and multiple component interventions. Healthcare professionals rated the TAI Toolkit with a mean SUS score of 71.4 (range: 57.5-80.0). CONCLUSION: Adherence can be improved using different interventions that the TAI Toolkit helps selecting. The TAI Toolkit was well received by healthcare professionals. Further research is required to test its validity, practicality and effectiveness in practice
Contrasting magma emplacement mechanisms within the Rogart igneous complex, NW Scotland, record the switch from regional contraction to strike-slip during the Caledonian orogeny
The Rogart igneous complex is unique within the northern Scottish Caledonides because it comprises an apparent continuum of magma types that records a progressive change in emplacement mechanisms related to large-scale tectonic controls. Syn-D2 leucogranites and late-D2 quartz monzodiorites were emplaced during crustal thickening and focused within the broad zone of ductile deformation associated with the Naver Thrust. In contrast, emplacement of the post-D2 composite central pluton was controlled by development of a steeply dipping dextral shear zone along the Loch Shin Line, interpreted as an anti-Riedel shear within the Great Glen Fault system. The mantle-derived nature of the late-to-post-D2 melts implies that the Naver Thrust and the Loch Shin Line were both crustal-scale structures along which magmas were channelled during deformation. A UāPb zircon age of 425Ā±1.5 Ma for the outer component of the central pluton provides an upper limit on regional deformation and metamorphism within host Moine rocks. These findings are consistent with the view that a fundamental change in tectonic regime occurred in the Scottish Caledonides at c. 425 Ma, corresponding to the switch from regional thrusting that resulted from the collision of Baltica and Laurentia, to the development of the orogen-parallel Great Glen Fault system
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