518 research outputs found
Illusions of gunk
The possibility of gunk has been used to argue against mereological nihilism. This paper explores two responses on the part of the microphysical mereological nihilist: (1) the contingency defence, which maintains that nihilism is true of the actual world; but that at other worlds, composition occurs; (2) the impossibility defence, which maintains that nihilism is necessary true, and so gunk worlds are impossible. The former is argued to be ultimately unstable; the latter faces the explanatorily burden of explaining the illusion that gunk is possible. It is argued that we can discharge this burden by focussing on the contingency of the microphysicalist aspect of microphysical mereological nihilism. The upshot is that gunk-based arguments against microphysical mereological nihilism can be resisted
Backbone and side chain H-1, N-15 and C-13 assignments for the oxidised and reduced forms of the oxidoreductase protein DsbA from Staphylococcus aureus
The function and dynamics of the thiol-disulfide oxidoreductase DsbA in the low-GC gram positive bacterium, Staphylococcus aureus, are yet to be elucidated. Here we report 13C, 15N and 1H assignments for the oxidised and reduced forms of SaDsbA as a prelude to further studies on the enzyme
(S)-(â)-Fluorenylethylchloroformate (FLEC) ; preparation using asymmetric transfer hydrogenation and application to the analysis and resolution of amines
Fluorenylethylchoroformate (FLEC) is a valuable chiral derivatisation reagent that is used for the resolution of a wide variety of chiral amines. Herein, we describe an improved preparation of (S)-(â)-FLEC using an efficient asymmetric catalytic transfer hydrogenation as the key step. We also demonstrate the application of FLEC as a chiral Fmoc equivalent for chiral resolution, with facile deprotection, of tetrahydroquinaldines, and its capacity for inducing regioselective outcomes in nitration reactions
How do pilot and feasibility studies inform randomised placebo-controlled trials in surgery? : A systematic review
© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.Peer reviewedPublisher PD
Non-orientable Boundary Superstring Field theory with Tachyon field
We use the BSFT method to study the unoriented open string field theory (type
I). The partition function on the Mobius strip is calculated. We find that, at
the one-loop level, the divergence coming from planar graph and unoriented
graph cancel each other as expected.Comment: 17 pages, 2 figures, references adde
Reporting of key methodological issues in placebo-controlled trials of surgery needs improvement:a systematic review
OBJECTIVES:To examine key methodological considerations for using a placebo intervention in randomized controlled trials (RCTs) evaluating invasive procedures, including surgery. STUDY DESIGN AND SETTING:RCTs comparing an invasive procedure with a placebo were included in this systematic review. Articles published from database inception to December 31, 2017, were retrieved from Ovid MEDLINE, Ovid EMBASE and CENTRAL electronic databases, by handsearching references and expert knowledge. Data on trial characteristics (clinical area, nature of invasive procedure, number of patients and centers) and key methodological (rationale for using placebos, minimization of risk, information provision, offering the treatment intervention to patients randomized to placebo, delivery of cointerventions, and intervention standardization and fidelity) were extracted and summarized descriptively. RESULTS:One hundred thirteen articles reporting 96 RCTs were identified. Most were conducted in gastrointestinal surgery (n = 40, 42%) and evaluated minimally invasive procedures (n = 44, 46%). Over two-thirds randomized fewer than 100 patients (n = 65, 68%) and a third were single center (n = 31, 32%). A third (n = 33, 34%) did not report a rationale for using a placebo. Most common strategies to minimize patient risk were operator skill (n = 22, 23%) and independent data monitoring (n = 28, 29%). Provision of patient information regarding placebo use was infrequently reported (n = 11, 11%). Treatment interventions were offered to patients randomized to placebo in 43 trials (45%). Cointerventions were inconsistently reported, but 64 trials (67%) stated that anesthesia was matched between groups. Attempts to standardize interventions and monitor their delivery were reported in n = 7, (7%) and n = 4, (4%) trials, respectively. CONCLUSION:Most placebo-controlled trials in surgery evaluate minor surgical procedures and currently there is inconsistent reporting of key trial methods. There is a need for guidance to optimize the transparency of trial reporting in this area
The Final Fate of the Rolling Tachyon
We propose an alternative interpretation of the boundary state for the
rolling tachyon, which may depict the time evolution of unstable D-branes in
string theory. Splitting the string variable in the temporal direction into the
classical part, which we may call "time" and the quantum one, we observe the
time dependent behaviour of the boundary. Using the fermion representation of
the rolling tachyon boundary state, we show that the boundary state correctly
describes the time-dependent decay process of the unstable D-brane into a
S-brane at the classical level.Comment: 9 pages, revte
Prescribing paradigm shift? Applying the 2019 European Society of Cardiology-led guidelines on âdiabetes, pre-diabetes, and cardiovascular diseaseâ to assess eligibility for sodium-glucose co-transporter-2 inhibitors or glucagon-like peptide-1 receptor agonists as first-line monotherapy (or add-on to metformin monotherapy) in type 2 diabetes in Scotland
Objective: In 2019, the European Society of Cardiology led and released new guidelines for diabetes cardiovascular risk management, reflecting recent evidence of cardiovascular disease (CVD) reduction with sodiumâglucose cotransporter 2 inhibitors (SGLT-2is) and some glucagon-like peptide 1 receptor agonists (GLP-1RAs) in type 2 diabetes (T2D). A key recommendation is that all those with T2D who are (antihyperglycemic) drug naĂŻve or on metformin monotherapy should be CVD risk stratified and an SGLT-2i or a GLP-1RA initiated in all those at high or very high risk, irrespective of glycated hemoglobin. We assessed the impact of these guidelines in Scotland were they introduced as is.Research design and methods: Using a nationwide diabetes register in Scotland, we did a cross-sectional analysis, using variables in our register for risk stratification at 1 January 2019. We were conservative in our definitions, assuming the absence of a risk factor where data were not available. The risk classifications were applied to people who were drug naĂŻve or on metformin monotherapy and the anticipated prescribing change calculated.Results: Of the 265,774 people with T2D in Scotland, 53,194 (20.0% of those with T2D) were drug naĂŻve, and56,906(21.4%) were on metformin monotherapy. Of these, 74.5%and72.4%, respectively, were estimated as at least high risk given the guideline risk definitions.Conclusions: Thus, 80,830 (30.4%) of all those with T2D (n 5 265,774) would start one of these drug classes according to table 7 and figure 3 of the guideline. The sizeable impact on drug budgets, enhanced clinical monitoring, and the trade-off with reduced CVD-related health care costs will need careful consideration.</p
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