275 research outputs found

    Two-spin subsystem entanglement in spin 1/2 rings with long range interactions

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    We consider the two-spin subsystem entanglement for eigenstates of the Hamiltonian H=∑1≀j<k≀N(1rj,k)ασj⋅σk H= \sum_{1\leq j< k \leq N} (\frac{1}{r_{j,k}})^{\alpha} {\mathbf \sigma}_j\cdot {\mathbf \sigma}_k for a ring of NN spins 1/2 with asssociated spin vector operator (ℏ/2)σj(\hbar /2){\bf \sigma}_j for the jj-th spin. Here rj,kr_{j,k} is the chord-distance betwen sites jj and kk. The case α=2\alpha =2 corresponds to the solvable Haldane-Shastry model whose spectrum has very high degeneracies not present for α≠2\alpha \neq 2. Two spin subsystem entanglement shows high sensistivity and distinguishes α=2\alpha =2 from α≠2\alpha \neq 2. There is no entanglement beyond nearest neighbors for all eigenstates when α=2\alpha =2. Whereas for α≠2\alpha \neq 2 one has selective entanglement at any distance for eigenstates of sufficiently high energy in a certain interval of α\alpha which depends on the energy. The ground state (which is a singlet only for even NN) does not have entanglement beyond nearest neighbors, and the nearest neighbor entanglement is virtually independent of the range of the interaction controlled by α\alpha.Comment: 16 figure

    Learning from sustainable development: education in the light of public issues

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    Education for sustainable development (ESD) is increasingly affecting environmental education policy and practice. In this article we show how sustainable development is mainly seen as a problem that can be tackled by applying the proper learning processes and how this perspective translates sustainability issues into learning problems of individuals. We present a different perspective on education in the context of sustainable development based on novel ways of thinking about citizenship education and emphasizing the importance of presenting issues of sustainable development as ‘public issues’, as matters of public concern. From this point of view, the focus is no longer on the competences that citizens must achieve, but on the democratic nature of the spaces and practices in which participation and citizenship can develop

    Massive hematuria due to ruptured iatrogenic aortic pseudoaneurysm: a case report.

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    We report an interesting case of massive haematuria secondary to a rupture of a pseudoa- neurysm of the abdominal aorta below the renal vessels. A 65-year-old woman present- ed at our institution with a painful massive haematuria and anaemia. Two months before, she undergone a pelvic surgery complicated by an accidental injury of the right ureter sutured with a end-to-end anastomosis. An abdominal computed tomography (CT) scan with intravenous contrast showed a right-sided hydronephrosis with clots in the lumen of the right pelvis with a massive retroperitoneal hematoma due to a rupture of a iatrogenic pseudoaneurysm of the abdominal aorta below the origin of the renal arteries

    (188)Re radiopharmaceuticals for radiosynovectomy: evaluation and comparison of tin colloid, hydroxyapatite and tin-ferric hydroxide macroaggregates

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    BACKGROUND: Radiosynovectomy is a therapy used to relieve pain and inflammation from rheumatoid arthritis and related diseases. In this study three (188)Re particulate compounds were characterized according to their physico-chemical properties and their biological behavior in rabbits. The results were compared in order to establish which was the radiopharmaceutical that better fits the requirements of this kind of radiotherapy. METHODS: Three radiopharmaceutical formulations, tin colloid, hydroxyapatite particles (HA) and ferric hydroxide macroaggregates coated with tin colloid (FHMA), were physically characterized (number, volume and surface of the particles). For this purpose laser diffraction methodology was used. To evaluate cavity leakage of activity the following studies in New Zealand rabbits were performed: scintigraphic images for 48 hr after intraarticular injection of each radiopharmaceutical, biodistribution at 48 hr and urine samples collection during the first 24 hr post-radiopharmaceutical administration. RESULTS: Labeling procedures for (188)Re-HA and (188)Re-Sn-FHMA were labour intensive while (188)Re-Sn was easily prepared. Furthermore, (188)Re-Sn colloid offered the greatest surface area in the 2–10 microm range and was obtained with a radiochemical purity over 95%, while percentage of bound activity for (188)Re-HA and (188)Re-Sn-FHMA were 55% and 92% respectively. Stability was verified for the three radiopharmaceuticals for 24 hr. Scintigraphic studies and biodistribution in rabbits after intraarticular administration of the radiopharmaceuticals showed relevant activity only in the knee, this being over 90% of the residual activity in the whole body at 48 hr in every case. Renal elimination of (188)Re-Sn colloid and (188)Re-Sn-FHMA was detected by activity measurements in urine samples, during the first 12 hr post-radiopharmaceutical injection. The percentage of activity retained in the knee was 69.1% for (188)Re-Sn colloid, 55.1% for (188)Re-Sn-FHMA and 33.6% for (188)Re-HA. CONCLUSION: The (188)Re-Sn colloid was easy to prepare, minimum facilities were required, was stable for 24 hr and showed minimal leakage from the joint after intraarticular injection into the rabbit's knee. Furthermore, (188)Re-Sn colloid has greater retention in the knee when it is compared with the other radiopharmaceuticals, so it could provide the best therapeutic effect/absorbed dose ratio for the patient

    A card game for the treatment of delusional ideas: A naturalistic pilot trial

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    BACKGROUND: "Michael's game" is a card game which aims at familiarizing healthcare professionals and patients with cognitive behavioral therapy of psychotic symptoms. This naturalistic study tests the feasibility and the impact of the intervention in various naturalistic settings. METHOD: Fifty five patients were recruited in seven centers. They were assessed in pre and post-test with the Peters Delusion Inventory – 21 items (PDI-21). RESULTS: Forty five patients completed the intervention significantly reducing their conviction and preoccupation scores on the PDI-21. CONCLUSION: This pilot study supports the feasibility and effectiveness of "Michael's game" in naturalistic setting. Additional studies could validate the game in a controlled fashion

    A novel patient-derived tumorgraft model with TRAF1-ALK anaplastic large-cell lymphoma translocation.

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    Although anaplastic large-cell lymphomas (ALCL) carrying anaplastic lymphoma kinase (ALK) have a relatively good prognosis, aggressive forms exist. We have identified a novel translocation, causing the fusion of the TRAF1 and ALK genes, in one patient who presented with a leukemic ALK+ ALCL (ALCL-11). To uncover the mechanisms leading to high-grade ALCL, we developed a human patient-derived tumorgraft (hPDT) line. Molecular characterization of primary and PDT cells demonstrated the activation of ALK and nuclear factor kB (NFkB) pathways. Genomic studies of ALCL-11 showed the TP53 loss and the in vivo subclonal expansion of lymphoma cells, lacking PRDM1/Blimp1 and carrying c-MYC gene amplification. The treatment with proteasome inhibitors of TRAF1-ALK cells led to the downregulation of p50/p52 and lymphoma growth inhibition. Moreover, a NFkB gene set classifier stratified ALCL in distinct subsets with different clinical outcome. Although a selective ALK inhibitor (CEP28122) resulted in a significant clinical response of hPDT mice, nevertheless the disease could not be eradicated. These data indicate that the activation of NFkB signaling contributes to the neoplastic phenotype of TRAF1-ALK ALCL. ALCL hPDTs are invaluable tools to validate the role of druggable molecules, predict therapeutic responses and implement patient specific therapies

    Psychological therapies for auditory hallucinations (voices): current status and key directions for future research

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    This report from the International Consortium on Hallucinations Research considers the current status and future directions in research on psychological therapies targeting auditory hallucinations (hearing voices). Therapy approaches have evolved from behavioral and coping-focused interventions, through formulation-driven interventions using methods from cognitive therapy, to a number of contemporary developments. Recent developments include the application of acceptance- and mindfulness-based approaches, and consolidation of methods for working with connections between voices and views of self, others, relationships and personal history. In this article, we discuss the development of therapies for voices and review the empirical findings. This review shows that psychological therapies are broadly effective for people with positive symptoms, but that more research is required to understand the specific application of therapies to voices. Six key research directions are identified: (1) moving beyond the focus on overall efficacy to understand specific therapeutic processes targeting voices, (2) better targeting psychological processes associated with voices such as trauma, cognitive mechanisms, and personal recovery, (3) more focused measurement of the intended outcomes of therapy, (4) understanding individual differences among voice hearers, (5) extending beyond a focus on voices and schizophrenia into other populations and sensory modalities, and (6) shaping interventions for service implementation
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