863 research outputs found
Message in a bottle : a tale of two Triassic temnospondyl (labyrinthodont) femora from Tasmania
In 1997 the senior author, while exploring the antique shops of Hobart, found in Suffolk Park Antiques an intriguing small, nineteenth-century, clear glass bottle. Labelled as "message in a bottle", it did indeed contain a note on a slip, cut from a visiting card, together with a wafer-thin, sub-triangular piece of dark, porous material (pl. 1). The handwritten note read "section shaft humerus labryinthodont, sandstone quarry, Hobart, 1856, Tas Museum".A further annotation, written at right angles to the preceding note, appears to read "Pro R.S.T 1898-9". Pro R.S.T. is an abbreviated reference to the Papers and Proceedings of the Royal Society of Tasmania, 1898-99.
This issue of the journal included a short note by WH. Twelvetrees and WF. Petterd describing and illustrating two labyrinthodont bones from Tasmania lodged in the Tasmanian Museum and Art Gallery (TMAG) collection. Here we trace the history of the two temnospondyl (labyrinthodont) bones, review the significance of these specimens and propose an explanation as to how part of one specimen came to be in the Suffolk Park Antiques sho
Comparison of the diagnostic yield and outcomes between standard 8 h capsule endoscopy and the new 12 h capsule endoscopy for investigating small bowel pathology
AIM: To evaluate the completion rate and diagnostic yield of the PillCam SB2-ex in comparison to the PillCam SB2. METHODS: Two hundred cases using the 8-h PillCam SB2 were retrospectively compared to 200 cases using the 12 h PillCam SB2-ex at a tertiary academic center. Endoscopically placed capsules were excluded from the study. Demographic information, indications for capsule endoscopy, capsule type, study length, completion of exam, clinically significant findings, timestamp of most distant finding, and significant findings beyond 8 h were recorded. RESULTS: The 8 and 12 h capsule groups were well matched respectively for both age (70.90 +/- 14.19 vs 71.93 +/- 13.80, P = 0.46) and gender (45.5% vs 48% male, P = 0.69). The most common indications for the procedure in both groups were anemia and obscure gastrointestinal bleeding. PillCam SB2-ex had a significantly higher completion rate than PillCam SB2 (88% vs 79.5%, P = 0.03). Overall, the diagnostic yield was greater for the 8 h capsule (48.5% for SB2 vs 35% for SB2-ex, P = 0.01). In 4/70 (5.7%) of abnormal SB2-ex exams the clinically significant finding was noted in the small bowel beyond the 8 h mark. CONCLUSION: In our study, we found the PillCam SB2-ex to have a significantly increased completion rate, though without any improvement in diagnostic yield compared to the PillCam SB2
Kim Akerman (Art Forum)
Kim Akerman is an anthropologist with extensive experience as a consultant and curator. Specialising in traditional and contemporary indigenous art and material culture, he has a focus on pearl shell, tools manufacture, rock art and dance of the Kimberley and Northern Territory
Zero Field precession and hysteretic threshold currents in spin torque oscillators with tilted polarizer
Using non-linear system theory and numerical simulations we map out the
static and dynamic phase diagram in zero applied field of a spin torque
oscillator with a tilted polarizer (TP-STO).We find that for sufficiently large
currents, even very small tilt angles (beta>1 degree) will lead to steady free
layer precession in zero field. Within a rather large range of tilt angles, 1
degree< beta <19 degree, we find coexisting static states and hysteretic
switching between these using only current. In a more narrow window (1
degree<beta<5 degree) one of the static states turns into a limit cycle
(precession). The coexistence of static and dynamic states in zero magnetic
field is unique to the tilted polarizer and leads to large hysteresis in the
upper and lower threshold currents for TP-STO operation.Comment: 5 pages, 4 figure
Clinical markers of Crohn\u27s disease severity and their association with opiate use
BACKGROUND: The safety of opiate use for patients with Crohn\u27s disease (CD) has long been a concern. The recent Crohn\u27s therapy, resource, evaluation, and assessment tool (TREAT) registry update has added to these concerns by demonstrating an association of opiate use with an increased risk of infection and death in CD. While the association is clear, the relationship of opiates to these negative outcomes is not. It is unknown whether opiates are a contributing factor to these negative outcomes or if their use is merely a marker of more severe disease. We hypothesized that opiate use is not harmful in CD but is a marker of disease severity and would be associated with commonly accepted clinical markers of severe CD such as early age at CD onset, disease duration, small intestinal involvement, a history of fistula or stricture, and lower quality of life (QOL) scores. METHODS: Data on CD history including pain medication usage were obtained from an interviewer directed survey of patients admitted to two tertiary care hospitals over a 2-year period. CD as the primary admitting diagnosis was not required. Active opiate use was defined by usage within the past month prior to admission. RESULTS: A total of 133 patients were approached to participate, of whom 108 consented to the survey, and 51 were active opiate users. Opiate using CD patients were more commonly smokers (22% vs. 3.45%, P \u3c 0.010), had fistulas (40% vs. 22.4%, P \u3c 0.048) and had a poorer quality of life score by short form inflammatory bowel disease questionnaire (mean 3.80 vs. 4.34, P \u3c 0.036) than non-opiate users. No difference was found between opiate users and non-users for age of diagnosis, disease duration, or a history of strictures. CONCLUSIONS: The study findings demonstrate that opiate use in CD is associated with markers of disease severity including fistulas, smoking, and lower QOL scores. The findings suggest that opiates may not be directly harmful to patients with CD, but may merely be another marker of disease severity. However, given opiates unproven benefits for long term CD pain control and risk of dependence, caution should still be exercised in their use
Proglacial icings as indicators of glacier thermal regime : ice thickness changes and icing occurrence in Svalbard
Proglacial icings (also known as naled or aufeis) are frequently observed in the forefields of polar glaciers. Their formation has been ascribed to the refreezing of upwelling groundwater that has originated from subglacial melt, and thus the presence of icings has been used as evidence of polythermal glacier regime. We provide an updated analysis of icing occurrence in Svalbard and test the utility of icings as an indicator of thermal regime by comparing icing presence with: (1) mean glacier thickness, as a proxy for present thermal regime; and (2) evidence of past surge activity, which is an indicator of past thermal regime. A total of 279 icings were identified from TopoSvalbard imagery covering the period 2008-2012, of which 143 corresponded to icings identified by Bukowska-Jania and Szafraniec (2005) from aerial photographs from 1990. Only 46% of icings observed in 2008-2012 were found to occur at glaciers with thicknesses consistent with a polythermal regime, meaning a large proportion were associated with glaciers predicted to be of a cold or transitional thermal regime. As a result, icing presence alone may be an unsuitable indicator of glacier regime. We further found that, of the 279 glaciers with icings, 63% of cold-based glaciers and 64% of transitional glaciers were associated with evidence of surge activity. We therefore suggest that proglacial icing formation in Svalbard may reflect historical (rather than present) thermal regime, and that icings possibly originate from groundwater effusion from subglacial taliks that persist for decades following glacier thinning and associated regime change
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Microflow of fluorescently labelled red blood cells in tumours expressing single isoforms of VEGF and their response to VEGF-R tyrosine kinase inhibition
In this work we studied the functional differences between the microcirculation of murine tumours that only express single isoforms of vascular endothelial growth factor-A (VEGF), VEGF120 and VEGF188, and the effect of VEGF receptor tyrosine kinase (VEGF-R TK) inhibition on their functional response to the vascular disrupting agent, combretastatin A-4 phosphate (CA-4-P). We used measurement of fluorescently- labelled red blood cell (RBC) velocities in tumour microvessels to study this functional response. RBC velocity for control VEGF120-expressing tumours was over 50% slower than for control VEGF188- expressing tumours, which may be due to the immature and haemorrhagic vasculature of the VEGF120 tumour. After chronic treatment with a VEGF-R tyrosine kinase inhibitor, SU5416, RBC velocities in VEGF120 tumours were significantly increased compared to control VEGF120 tumours, and similar to velocities in both VEGF188 treatment groups. Control and SU5416 treated VEGF188 tumours were not different from each other. Treatment of VEGF120 tumours with SU5416 reduced their vascular response to CA-4-P to a similar level to the VEGF188 tumours. Differential expression of VEGF isoforms not only affected vascular function in untreated tumours but also impacted on response to a vascular disrupting drug, CA-4-P, alone and in combination with an anti-angiogenic approach involving VEGF-R TK inhibition. Analysis of RBC velocities is a useful tool in measuring functional responses to vascular targeted treatments
Did we do everything we could have? Nursesâ contributions to medicines optimisation: a mixed method study
Aim
To explore UK professionalsâ interpretations of medicines optimization and expansion of nursesâ roles.
Design
This mixedâmethods study sought professionalsâ views on nursesâ involvement, competency and engagement in monitoring patients for adverse effects of medicines, monitoring adherence, prescribing and patient education.
Method
An online survey and interviews were undertaken with nurses, doctors and pharmacists in Wales and England, May 2018 to July 2019.
Results
In all, 220 nurses, 17 doctors and 62 pharmacists responded to the online survey, and 24 professionals were interviewed. Nurses were divided over extending their roles, with 123/220 (55.9%) wishing to extend roles in monitoring patients for possible adverse drug reactions (ADRs), 111/220 (50.5%) in adherence monitoring, 121/220 (55.0%) in prescribing and 122/220 (55.4%) in patient education. The bestâqualified nurses were the most willing to increase involvement in monitoring patients for ADRs (aOR 13.00, 1.56â108.01). Interviews revealed that both nurses and doctors assumed the other profession was undertaking this monitoring. Respondents agreed that increasing nursesâ involvement in medicines optimization would improve patient care, but expressed reservations about nursesâ competencies. Collaboration between nurses and doctors was suboptimal (rated 7/10 at best) and between nurses and pharmacists even more so (6/10 at best).
Conclusion
Juxtaposition of datasets identified problems with medicines optimization: although most respondents agreed that increasing nursesâ involvement would positively impact practice, their educational preparation was a barrier. Only ~50% of nurses were willing to expand their roles to fill the hiatus in care identified and ensure that at least one profession was taking responsibility for ADR monitoring.
Impact
To improve multiprofessional team working and promote patient safety, nurse leaders should ensure patients are monitored for possible ADRs by at least one profession. Initiatives expanding nursesâ roles in medicines optimization and prescribing might be best targeted towards the more educated nurses, who have multidisciplinary support
Self-assembled supramolecular structures of O,N,NâČ tridentate imidazoleâphenol Schiff base compounds
Three imidazole-derived Schiff base compounds comprising an N-methyl imidazole group coupled to a phenol ring through an imine bond were synthesised. The structures differ by the substituent on the phenol ring at the 4-position: methyl (1), tert-butyl (2) and hydrogen (3). The compounds were synthesised using both a traditional reflux in solvent as well as an environmentally friendly solid-state reaction. Compounds (1)â(3) as well as the hemihydrate of (3) were all studied by single crystal X-ray diffraction. The asymmetric unit of compound (1) consists of two nominally planar molecules linked by hydrogen bonds to form a dimeric supramolecular structure. This dimeric structure was ubiquitous for the anhydrous forms of (1)â(3). The complementary hydrogen bonding motif between the imidazole N atoms and the phenol OH results in a stable 16-membered hydrogen-bonded ring. The asymmetric unit of (3) comprises two symmetry-independent molecules one of which has co-planar imidazole and phenol rings while the other shows a significantly oblique orientation. The hemihydrate of (3) similarly forms extensive hydrogen bonds, though in the form of a water-bridged dimeric structure. The hydrogen bond lengths (DâŻA) for compounds (1)â(3) are relatively short, ranging from 2.662(1) to 2.688(1) Ă
. DFT was used to understand the relative stability of the monomeric and dimeric species. These showed the hydrogen-bonded supramolecular structures were ca. 101 kJ molâ1 lower in energy than the non-interacting monomers. Scan simulations were used to calculate the total energy of the molecule as a function of phenyl ring rotation and showed why the expected planar configuration for a conjugated Ï-system was not observed experimentally. The barrier to rotation was found to be relatively low, 7.97(6) kJ molâ1, with the lowest energy conformations subtending dihedral angles of 22.319, 24.265 and 25.319° for molecules (1), (2) and (3), respectively. The electrostatic potential maps are able to succinctly explain the stability of the hydrogen bonds through the partial charges of the interacting atoms. TD-DFT simulations and analysis of the simulated and experimental UV/visible spectra suggest that the dimeric supramolecular structure is a stable species in solution. This was confirmed through 1H NMR titrations and an equilibrium constant of 0.16(5) Mâ1 was estimated
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