A cascade of magnetic field induced spin transitions in LaCoO3

We present magnetization and magnetostriction studies of the insulating perovskite LaCoO3 in magnetic fields approaching 100 T. In marked contrast with expectations from single-ion models, the data reveal two distinct first-order spin transitions and well-defined magnetization plateaux. The magnetization at the higher plateau is only about half the saturation value expected for spin-1 Co3+ ions. These findings strongly suggest collective behavior induced by strong interactions between different electronic -- and therefore spin -- configurations of Co3+ ions. We propose a model of these interactions that predicts crystalline spin textures and a cascade of four magnetic phase transitions at high fields, of which the first two account for the experimental data.Comment: 5 pages + supplementary materials, 5 figure

Large-scale reconfigurable continuously-coupled integrated optical circuits for photonic quantum information processing

Quantum photonic platforms are emerging as the most promising to prove a computational advantage. Here we present a novel reconfigurable integrated interferometer for large-scale implementation of Boson Sampling based on the continuous coupling of waveguides

Justifications-on-demand as a device to promote shifts of attention associated with relational thinking in elementary arithmetic

Student responses to arithmetical questions that can be solved by using arithmetical structure can serve to reveal the extent and nature of relational, as opposed to computational thinking. Here, student responses to probes which require them to justify-on-demand are analysed using a conceptual framework which highlights distinctions between different forms of attention. We analyse a number of actions observed in students in terms of forms of attention and shifts between them: in the short-term (in the moment), medium-term (over several tasks), and long-term (over a year). The main factors conditioning students´ attention and its movement are identified and some didactical consequences are proposed

Nuclear Ground State Observables and QCD Scaling in a Refined Relativistic Point Coupling Model

We present results obtained in the calculation of nuclear ground state properties in relativistic Hartree approximation using a Lagrangian whose QCD-scaled coupling constants are all natural (dimensionless and of order 1). Our model consists of four-, six-, and eight-fermion point couplings (contact interactions) together with derivative terms representing, respectively, two-, three-, and four-body forces and the finite ranges of the corresponding mesonic interactions. The coupling constants have been determined in a self-consistent procedure that solves the model equations for representative nuclei simultaneously in a generalized nonlinear least-squares adjustment algorithm. The extracted coupling constants allow us to predict ground state properties of a much larger set of even-even nuclei to good accuracy. The fact that the extracted coupling constants are all natural leads to the conclusion that QCD scaling and chiral symmetry apply to finite nuclei.Comment: 44 pages, 13 figures, 9 tables, REVTEX, accepted for publication in Phys. Rev.

Thyroid control over biomembranes: VI. Lipids in liver mitochondria and microsomes of hypothyroid rats

The lipids of liver mitochondria prepared from normal rats and from rats made hypothyroid by thyroidectomy and injection with131INa contained similar amounts, per mg protein, of total lipids, phospholipids, neutral lipids and lipid phosphorus. Hypothyroidism caused a doubling of the relative amounts of mitochondrial cardiolipins (CL; to 20.5% of the phospholipid P) and an accompanying trend (although statistically not significant) toward decreased amounts of both phosphatidylcholines (PC) and phosphatidylserines (PS), with phosphatidylethanolamines (PE) remaining unchanged. The pattern of elevated 18∶2 fatty acyl content and depleted 20∶4 acyl groups of the mitochondrial phospholipids of hypothyroid preparations was reflected to varying degrees in the resolved phospholipids, with PC showing greater degrees of abnormality than PE, and CL showing none. Hypothyroidism produced the same abnormal pattern of fatty acyl distributions in liver microsomal total lipids as was found in the mitochondria. Hypothyroid rats, when killed 6 hr after injection of [1‐14C] labeled linoleate, showed the following abnormalities: the liver incorporated less label into lipids, and converted 18∶2 not exclusively to 20∶4 (as normals do) but instead incorporated the label mainly into saturated fatty acids. These data, together with the known decrease in β‐oxidation, suggest that hypothyroidism involves possible defective step(s) in the conversion of 18∶2 to 20∶4.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142296/1/lipd0328.pd

Thyroid hormone action on mitochondria

Measurements of fluorescence at >420 nm and extracted NADPH in mitochondria obtained from the livers of hypothyroid rats show that the addition of Pi, ADP and glutamate rapidly reduces over 90% of the total reducible intrinsic pyridine nucleotides in State 3, compared with 20% in normals. The total fluorescence intensity change and reducible NADP + is about twice normal in hypothyroid mitochondria. Adding 6–30 µM l -thyroxine to hypothyroid mitochondria in vitro decreases and delays the substrate-induced reduction of pyridine nucleotides, and excludes both NADP + from such reduction and NADPH from oxidation by added ADP + Pi, without changing the high NADP(H) content. The correcting actions of the hormone are rapidly reversed by albumin, probably by binding free hormone. Changes in respiration do not appear to account for these observations. There is indirect evidence for decreased phosphorylation of added ADP in hypothyroid mitochondria, and a correction by added hormone. The hormonal actions on NADP(H) redox reactions are not reproduced by 1 to 6 µM dinitrophenol in vitro . l -Thyroxine appears to specifically block the participation of NADP (H) in redox reactions in mitochondria from hypothyroid rats, perhaps by effecting a sequestration of the nucleotide, by inhibiting the pyridine nucleotide transhydrogenase, or by activating an energy-linked process that competes with transhydrogenation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44803/1/10863_2004_Article_BF00761448.pd

Combined use of maxillomandibular swing approach and neurosurgical ultrasonic aspirator in the management of extensive clival chordoma: A case report

<p>Abstract</p> <p>Introduction</p> <p>Chordoma is a rare malignant tumour with an incidence of metastasis of less than 10 percent. Usually arising from clivus its posterior extension may involve the brainstem before presenting as nasal mass and obstruction. Surgery is the main mode of treatment with adjuvant radiotherapy. However surgery is rarely possible for a large intracranial lesion.</p> <p>Case presentation</p> <p>We report the case of an adolescent patient with a chordoma extending posteriorly to the brainstem and anteriorly to the nasopharynx and managed by the combination of resection using a maxillomandibular swing approach and the use of a neurosurgical ultrasonic aspirator.</p> <p>Conclusion</p> <p>Maxillomandibular swing approach provides good access for large nasopharyngeal tumour extending brainstem area.</p

Bose-Einstein Correlations in e+e- to W+W- at 172 and 183 GeV

Bose-Einstein correlations between like-charge pions are studied in hadronic final states produced by e+e- annihilations at center-of-mass energies of 172 and 183 GeV. Three event samples are studied, each dominated by one of the processes W+W- to qqlnu, W+W- to qqqq, or (Z/g)* to qq. After demonstrating the existence of Bose-Einstein correlations in W decays, an attempt is made to determine Bose-Einstein correlations for pions originating from the same W boson and from different W bosons, as well as for pions from (Z/g)* to qq events. The following results are obtained for the individual chaoticity parameters lambda assuming a common source radius R: lambda_same = 0.63 +- 0.19 +- 0.14, lambda_diff = 0.22 +- 0.53 +- 0.14, lambda_Z = 0.47 +- 0.11 +- 0.08, R = 0.92 +- 0.09 +- 0.09. In each case, the first error is statistical and the second is systematic. At the current level of statistical precision it is not established whether Bose-Einstein correlations, between pions from different W bosons exist or not.Comment: 24 pages, LaTeX, including 6 eps figures, submitted to European Physical Journal

Representations of sport in the revolutionary socialist press in Britain, 1988–2012

This paper considers how sport presents a dualism to those on the far left of the political spectrum. A long-standing, passionate debate has existed on the contradictory role played by sport, polarised between those who reject it as a bourgeois capitalist plague and those who argue for its reclamation and reformation. A case study is offered of a political party that has consistently used revolutionary Marxism as the basis for its activity and how this party, the largest in Britain, addresses sport in its publications. The study draws on empirical data to illustrate this debate by reporting findings from three socialist publications. When sport did feature it was often in relation to high profile sporting events with a critical tone adopted and typically focused on issues of commodification, exploitation and alienation of athletes and supporters. However, readers’ letters, printed in the same publications, revealed how this interpretation was not universally accepted, thus illustrating the contradictory nature of sport for those on the far left