30,245 research outputs found

    Local moment, itinerancy and deviation from Fermi liquid behavior in Nax_xCoO2_2 for 0.71x0.840.71 \leq x \leq 0.84

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    Here we report the observation of Fermi surface (FS) pockets via the Shubnikov de Haas effect in Nax_xCoO2_2 for x=0.71x = 0.71 and 0.84, respectively. Our observations indicate that the FS expected for each compound intersects their corresponding Brillouin zones, as defined by the previously reported superlattice structures, leading to small reconstructed FS pockets, but only if a precise number of holes per unit cell is \emph{localized}. For 0.71x<0.750.71 \leq x < 0.75 the coexistence of itinerant carriers and localized S=1/2S =1/2 spins on a paramagnetic triangular superlattice leads at low temperatures to the observation of a deviation from standard Fermi-liquid behavior in the electrical transport and heat capacity properties, suggesting the formation of some kind of quantum spin-liquid ground state.Comment: 4 pages, 4 figure

    High fidelity sorting of remarkably similar components via metal-mediated assembly.

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    Subtle differences in ligand coordination angle and rigidity lead to high fidelity sorting between individual components displaying identical coordination motifs upon metal-mediated self-assembly. Narcissistic self-sorting can be achieved between highly similar ligands that vary minimally in rigidity and internal coordination angle upon combination with Fe(ii) ions and 2-formylpyridine. Selective, sequential cage formation can be precisely controlled in a single flask from a mix of three different core ligands (and 33 total components) differing only in the hybridization of one group that is uninvolved in the metal coordination process

    Encountering authority and avoiding trouble: young migrant men’s narratives of negotiation in Europe

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    Drawing on data from seven European countries (Czech Republic, Finland, France, Germany, Ireland, Italy and the United Kingdom), this article seeks to identify how young migrant men engage with authority and avoid conflict against a backdrop of increasing hostility towards migrants in many European countries. As this article contends, even those with permanent residency status in the host country often find themselves having to justify their legitimacy to carry out daily tasks, resulting in many young male migrants living with feelings of perpetual insecurity. As such, a number of coping strategies are employed by young migrant men in order to assuage such feelings and mitigate potential risks. Focusing on the lived experiences of this group, as described in narrative interviews, our study found that many young migrant men are required to enter into negotiations with authority figures, where there is a considerable power differential. Acting as risk assessors, they find themselves forced to navigate complex and challenging social relations and support networks. We show how self-limiting behaviour intended to avoid or control interactions with authority and the negotiations conducted to minimize the risk of ‘trouble’ by young migrant men not only are problematic in the context of day-to-day activities but can very often have a detrimental impact on their lives

    Three-loop HTL QCD thermodynamics

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    The hard-thermal-loop perturbation theory (HTLpt) framework is used to calculate the thermodynamic functions of a quark-gluon plasma to three-loop order. This is the highest order accessible by finite temperature perturbation theory applied to a non-Abelian gauge theory before the high-temperature infrared catastrophe. All ultraviolet divergences are eliminated by renormalization of the vacuum, the HTL mass parameters, and the strong coupling constant. After choosing a prescription for the mass parameters, the three-loop results for the pressure and trace anomaly are found to be in very good agreement with recent lattice data down to T23TcT \sim 2-3\,T_c, which are temperatures accessible by current and forthcoming heavy-ion collision experiments.Comment: 27 pages, 11 figures; corresponds with published version in JHE

    Low-energy electron scattering by tetrahydrofuran

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    Cross sections for elastic scattering of low-energy electrons by tetrahydrofuran, a prototype for the furanose ring found in the backbone of DNA, have been measured and calculated over a wide energy range, with an emphasis on energies below 6 eV, where previous data are scarce. The measurements employ a thin-aperture version of the relative-flow method, while the calculations employ the Schwinger multichannel method with an extensive treatment of polarization effects. Comparisons with earlier results, both experimental and theoretical, are presented and discussed. A proper accounting for the strong permanent electric dipole of tetrahydrofuran is found to be essential to obtaining reliable cross sections, especially at energies below 5 eV

    First reports of computed tomographic colonography for the screening of colorectal polyps in acromegalic patients

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    *Aim:* To analyze the CTC performance for the screening of colorectal polyps in acromegalic patients. &#xd;&#xa;&#xd;&#xa;*Materials and Methods:* A prospective study of 21 acromegalic patients, 12 male and 9 female, average age 49, who underwent CTC and CC. CTC was performed with a GE Helical Multislice Computed Tomography Apparatus. The colonoscopy was performed, in the same day, without previous knowledge of the CTC diagnostics. The study evaluated the capacity of CTC to detect patients with colorectal polyps and identify each colorectal lesion described by CC. &#xd;&#xa;&#xd;&#xa;*Results:* In two patients (2/21), CC was incomplete. However, in all patients CTC was complete. In Phase I (&#x201c;Per Patient&#x201d;), CTC diagnosed 8 of the 9 patients with colorectal polyps and showed 88% sensitivity, 75% specificity and 81% accuracy. In Phase II (&#x201c;Per Polyp&#x201d;), out of the 21 acromegalic patients included in this study, 12 presented normal findings at CC. A total of 19 polyps were identified in 9 patients. 10 of the 19 polyps were smaller than 10 mm, and 9 were equal to or larger than 10. CTC identified 7 of the 9 polyps &#x2265; 10 mm described by CC and only 6 of the 10 small polyps identified at CC were detected by CTC. The histological analysis of resected lesions revealed 12 tubular adenomas, 6 hyperplastic polyps and 1 colonic tubulo-villous adenoma with an adenocarcinoma focus. &#xd;&#xa;&#xd;&#xa;*Conclusion:* In this study, CTC was performed without complications and a complete and safe colorectal evaluation was possible in all acromegalic patients. Moreover, CTC showed good sensitivity to identify acromegalic patients with colorectal polyps

    Understanding How Student Nurses Experience Morally Distressing Situations: Caring for Patients with Different Values and Beliefs in the Clinical Environment

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    Introduction/Background: Moral distress and related concepts surrounding morality and ethical decision-making have been given much attention in nursing. Despite the general consensus that moral distress is an affective response to being unable to act morally, the literature attests to the need for increased clarity regarding theoretical and conceptual constructs used to describe precisely what the experience of moral distress involves. The purpose of this study is to understand how student nurses experience morally distressing situations when caring for patients with different values and beliefs than their own in the clinical environment Methods: This study is based on secondary analysis of participant data. The stories of eight student nurses who completed the original study were reviewed following Yin’s multiple-case study design. Results: Findings suggest there is a subtle form of moral distress that has been under appreciated in the literature and differs from Jameton’s classic definition. While traditional institutional triggers to moral distress are pervasive, personal conflict as a result of differing value systems may be a moral challenge faced by nursing students working with culturally diverse patients. Conclusion: Ethics education is needed in nursing school to reduce moral distress in the clinical environment. Nursing students need opportunities to develop moral reasoning skills in addition to their clinical skills. A philosophical approach to ethics education may be needed to prevent and alleviate moral distress

    Cost effectiveness analysis of larval therapy for leg ulcers

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    Objective: To assess the cost effectiveness of larval therapy compared with hydrogel in the management of leg ulcers. Design: Cost effectiveness and cost utility analyses carried out alongside a pragmatic multicentre, randomised, open trial with equal randomisation. Population: Intention to treat population comprising 267 patients with a venous or mixed venous and arterial ulcers with at least 25% coverage of slough or necrotic tissue. Interventions: Patients were randomly allocated to debridement with bagged larvae, loose larvae, or hydrogel. Main outcome measure: The time horizon was 12 months and costs were estimated from the UK National Health Service perspective. Cost effectiveness outcomes are expressed in terms of incremental costs per ulcer-free day (cost effectiveness analysis) and incremental costs per quality adjusted life years (cost utility analysis). Results: The larvae arms were pooled for the main analysis. Treatment with larval therapy cost, on average, 96.70 pound ((sic)109.61; $140.57) more per participant per year (95% confidence interval -491.9 pound to 685.8) pound than treatment with hydrogel. Participants treated with larval therapy healed, on average, 2.42 days before those in the hydrogel arm (95% confidence interval -0.95 to 31. 91 days) and had a slightly better health related quality of life, as the annual difference in QALYs was 0.011 (95% confidence interval -0.067 to 0.071). However, none of these differences was statistically significant. The incremental cost effectiveness ratio for the base case analysis was estimated at 8826 pound per QALY gained and 40 pound per ulcer-free day. Considerable uncertainty surrounds the outcome estimates. Conclusions: Debridement of sloughy or necrotic leg ulcers with larval therapy is likely to produce similar health benefits and have similar costs to treatment with hydrogel. Trial registration: Current Controlled Trials ISRCTN55114812 and National Research Register N0484123692
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