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1.
J Synchrotron Radiat ; 28(Pt 5): 1455-1465, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34475293

RESUMEN

Exploitation of X-ray circular polarized beams to study forbidden Bragg reflections and new information that could be obtained in these experiments are discussed. It is shown that the intensities of such reflections can be different for the right- and left-circular polarizations (i.e. exhibiting circular dichroism) even for the dipole-dipole resonant transitions involved in the scattering process. This difference can be observed only in crystals having no center of inversion. Here, this approach is used to study helicity-dependent resonant diffraction in copper metaborate CuB2O4 single crystal, which is non-centrosymmetric but achiral. Nonetheless, a strong circular dichroism has been observed for hh0 forbidden reflections in the vicinity of the Cu K-edge. This effect is shown to originate from dipolar transitions in Cu atoms occupying the 8(d) Wyckoff position only.

2.
Vasa ; 50(1): 52-58, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32697148

RESUMEN

Background: Endovascular venous stenting with dedicated venous stents for the treatment of chronic venous outflow obstruction is developing as efficacious alternative to conservative therapy or open surgery. However, so far, mid- and long-term evidence on effectiveness and safety is poor. Patients and methods: The prospective, single-center, observational study enrolled consecutive patients with chronic non-thrombotic iliac vein lesions (NIVL) or post-thrombotic iliofemoral obstructions (PTO). From February 2016 to April 2017, patients underwent implantation of open cell, self-expandable dedicated venous stents. Short-term symptomatic improvement, patency, and complication rate were favorable. Evaluation at 2-years included improvement in the revised venous clinical severity score (rVCSS), patency, stent migration, major target limb events, clinically important pulmonary embolism, major bleeding, and all-cause mortality. Results: A total of 79 patients (57 ± 16 years, 44 female) were evaluated. At 2 years, rVCCS improved by 4.3 ± 2.7 (p < 0.001). Substantial clinical improvement of ≥ 2 score points was achieved in 86.4% (38 of 44) of patients. Improvement was not associated with thrombotic pathogenesis (regression coefficient [B] with PTO = 0.6 [95%CI: -1.1 to 2.3], p = 0.48). At 2 years, all ulcers (in 8 of 79 patients) were healed and none recurred. Two-year primary patency was 95.5% (95%CI: 86.5 to 98.5) with no difference between NIVL- and PTO-patients (log-rank p = 0.83). Target vessel revascularization was conducted in two PTO- and one NIVL-patients in the period of 34 days to 156 days from index procedure, resulting in a secondary patency of 100%. No stent migration, target limb deep vein thrombosis, major amputation, pulmonary embolism, or death occurred. Conclusions: Venovo venous open cell self-expanding stent implantation for chronic outflow obstruction was efficacious and provided a sufficient level of safety throughout 2 years.


Asunto(s)
Procedimientos Endovasculares/métodos , Vena Ilíaca/cirugía , Síndrome de May-Thurner/cirugía , Stents , Adulto , Anciano , Enfermedad Crónica , Femenino , Alemania , Humanos , Vena Ilíaca/diagnóstico por imagen , Síndrome de May-Thurner/diagnóstico por imagen , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Resultado del Tratamiento , Grado de Desobstrucción Vascular
3.
Phys Rev Lett ; 123(20): 207201, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31809079

RESUMEN

The magnitude of the orbital magnetic moment and its role as a trigger of the Verwey transition in the prototypical Mott insulator, magnetite, remain contentious. Using 1s2p resonant inelastic x-ray scattering angle distribution (RIXS-AD), we prove the existence of noncollinear orbital magnetic ordering and infer the presence of dynamical distortion creating a polaronic precursor for the metal to insulator transition. These conclusions are based on a subtle angular shift of the RIXS-AD spectral intensity as a function of the magnetic field orientation. Theoretical simulations show that these results are only consistent with noncollinear magnetic orbital ordering. To further support these claims we perform Fe K-edge x-ray magnetic circular dichroism in order to quantify the Fe average orbital magnetic moment.

4.
Vasa ; 48(3): 270-275, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30526435

RESUMEN

Background: We sought to determine the patency and clinical symptom relief following the usage of the sinus-Obliquus venous stent in the endovascular treatment of venous obstruction of the ilio-femoral track in short-term. Patients and methods: 48 patients (62 % female, mean age 57 years) with chronic unilateral post-thrombotic obstruction (PTO) and non-thrombotic iliac vein obstructive lesions (NIVL) without involvement of inferior vena cava receiving a sinus-Obliquus venous stent was included in the analysis. Clinical improvement determined by the revised venous clinical severity score (rVCSS) as well as the clinical, etiologic, anatomic and pathophysiologic score (CEAP), safety, and stent patency rates were determined at baseline and at 1, 6 and 12 months after stent placement. Ten of the 48 included patients had a venous ulceration. Results: Primary patency rates were 98 % at FU1, 94 % at FU2 and 94 % at FU3, respectively. Secondary patency was 100 % at FU1, 96 % at FU2 and remained 96 % at FU3. At 12 months, the mean rVCSS dropped from 9.0 to 4.8 points (p < 0.001) whereas the mean CEAP improved from 3.45 to 2.96 (p < 0.001). A substantial healing of ulcerations was observed in 8 of 10 patients with initial venous ulceration. There were no relevant safety concerns noticed. Conclusions: Even though long-term studies are missing, the sinus-Obliquus venous stent already showed very promising patency rates at short term, associated with substantial clinical improvement and low device-related complications in both NIVL and PTS.


Asunto(s)
Stents , Femenino , Humanos , Vena Ilíaca , Masculino , Persona de Mediana Edad , Flebografía , Síndrome Postrombótico , Sistema de Registros , Estudios Retrospectivos , Resultado del Tratamiento , Grado de Desobstrucción Vascular
5.
Vasa ; 48(2): 175-180, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30451095

RESUMEN

BACKGROUND: We sought to determine the patency and clinical symptom relief of the Venovo venous stent in the endovascular treatment of non-thrombotic (NIVL) or post-thrombotic venous obstruction (PTO) of the iliofemoral track over a period of 6 months. PATIENTS AND METHODS: A total of 80 patients (45 female, mean age 57 years) treated in 2016 and 2017 were included in the Arnsberg venous registry. Clinical improvement was determined by the revised venous clinical severity score (rVCSS) as well as the clinical, etiologic, anatomic and pathophysiologic (CEAP) score. Primary and secondary stent patency was evaluated using duplex ultrasound. RESULTS: Overall 6-months patency rates were 98 % for primary and 100 % for secondary patency. For NIVL primary patency was 97 %, whereas for PTO primary patency was 96 %. Early stent re-occlusion occurred in 3 patients within 34, 59 and 156 days after intervention. Two of these patients were successfully treated by endovascular mechanical thrombectomy and stent in stent implantation. Clinical improvement with a gain of ≥ 2 rVCSS levels was observed in 51 %. CEAP scores decreased from 4.3 to 2.7. CONCLUSIONS: In this first time report the novel Venovo venous stent showed adequate patency rates associated with reasonable clinical improvement and low device-related complications throughout a 6-months-follow-up in both NIVL and PTO.


Asunto(s)
Síndrome Postrombótico , Stents , Trombosis de la Vena , Femenino , Vena Femoral , Humanos , Vena Ilíaca , Persona de Mediana Edad , Flebografía , Sistema de Registros , Resultado del Tratamiento , Grado de Desobstrucción Vascular
6.
Phys Rev Lett ; 119(16): 160503, 2017 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-29099227

RESUMEN

We develop a generalized framework for constructing many-body-interaction operations either in linear time or in logarithmic time with a linear number of ancilla qubits. Exact gate decompositions are given for Pauli strings, many-control Toffoli gates, number- and parity-conserving interactions, unitary coupled cluster operations, and sparse matrix generators. We provide a linear time protocol that works by creating a superposition of exponentially many different possible operator strings and then uses dynamical decoupling methodology to undo all the unwanted terms. A logarithmic time protocol overcomes the speed limit of the first by using ancilla registers to condition evolution to the support of the desired many-body interaction before using parallel chaining operations to expand the string length. The two techniques improve substantially on current strategies (reductions in time and space ranging from linear to exponential), are applicable to different physical interaction mechanisms such as cnot, XX, and XX+YY, and generalize to a wide range of many-body operators.

7.
Phys Rev Lett ; 119(15): 157204, 2017 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-29077471

RESUMEN

We measure x-ray magnetic circular dichroism (XMCD) spectra at the Pu M_{4,5} absorption edges from a newly prepared high-quality single crystal of the heavy-fermion superconductor ^{242}PuCoGa_{5}, exhibiting a critical temperature T_{c}=18.7 K. The experiment probes the vortex phase below T_{c} and shows that an external magnetic field induces a Pu 5f magnetic moment at 2 K equal to the temperature-independent moment measured in the normal phase up to 300 K by a superconducting quantum interference device. This observation is in agreement with theoretical models claiming that the Pu atoms in PuCoGa_{5} have a nonmagnetic singlet ground state resulting from the hybridization of the conduction electrons with the intermediate-valence 5f electronic shell. Unexpectedly, XMCD spectra show that the orbital component of the 5f magnetic moment increases significantly between 30 and 2 K; the antiparallel spin component increases as well, leaving the total moment practically constant. We suggest that this indicates a low-temperature breakdown of the complete Kondo-like screening of the local 5f moment.

8.
Cell Microbiol ; 18(1): 46-65, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26149128

RESUMEN

Microbial pathogens have developed several mechanisms to modulate and interfere with host cell cycle progression. In this study, we analysed the effect of the human pathogen Neisseria meningitidis on cell cycle in a brain endothelial cell line as well as in primary brain endothelial cells. We found that N. Meningitidis causes an accumulation of cells in the S phase early at 3 and at 24 h post-infection that was paralleled by a decrease of cells in G2/M phase. Importantly, the outer membrane proteins of the colony opacity-associated (Opa) protein family as well as the Opc protein proved to trigger the accumulation of cells in the S phase. A focused cell cycle reverse transcription quantitative polymerase chain reaction-based array and integrated network analysis revealed changes in the abundance of several cell cycle regulatory mRNAs, including the cell cycle inhibitors p21(WAF1/CIP1) and cyclin G2. These alterations were reflected in changes in protein expression levels and/or relocalization in N. meningitidis-infected cells. Moreover, an increase in p21(WAF1/CIP1) expression was found to be p53 independent. Genetic ablation of p21(WAF1/CIP1) and cyclin G2 abrogated N. meningitidis-induced S phase accumulation. Finally, by measuring the levels of the biomarker 8-hydroxydeoxyguanosine and phosphorylation of the histone variant H2AX, we provide evidence that N. meningitidis induces oxidative DNA damage in infected cells.


Asunto(s)
Puntos de Control del Ciclo Celular , Ciclina G2/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Células Endoteliales/microbiología , Interacciones Huésped-Patógeno , Neisseria meningitidis/patogenicidad , Fase S , Proteínas de la Membrana Bacteriana Externa/metabolismo , Encéfalo , Células Cultivadas , Células Endoteliales/fisiología , Perfilación de la Expresión Génica , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
Appetite ; 118: 168-173, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28797702

RESUMEN

Research on eating behavior is limited by an overreliance on self-report. It is well known that actual food intake is frequently underreported, and it is likely that this problem is overrepresented in vulnerable populations. The present research tested a chewing detection method that could assist self-report methods. A trained sample of 15 participants (usable data of 14 participants) kept detailed eating records during one day and one night while carrying a recording device. Signals recorded from electromyography sensors unobtrusively placed behind the right ear were used to develop a chewing detection algorithm. Results showed that eating could be detected with high accuracy (sensitivity, specificity >90%) compared to trained self-report. Thus, electromyography-based eating detection might usefully complement future food intake studies in healthy and vulnerable populations.


Asunto(s)
Ingestión de Alimentos , Electromiografía , Monitoreo Ambulatorio/métodos , Adolescente , Adulto , Algoritmos , Índice de Masa Corporal , Femenino , Humanos , Masculino , Masticación , Evaluación Nutricional , Autoinforme , Sensibilidad y Especificidad , Adulto Joven
10.
Infect Immun ; 84(10): 2758-70, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27430269

RESUMEN

Microbial pathogens have developed several mechanisms to modulate and interfere with host cell cycle progression. In this study, we analyzed the effect of the human pathogen Neisseria meningitidis on the cell cycle of epithelial cells. Two pathogenic isolates, as well as two carrier isolates, were tested for their ability to adhere to and invade into the epithelial cell lines Detroit 562 and NP69 and to modulate the cell cycle. We found that all isolates adhered equally well to both Detroit 562 and NP69 cells, whereas the carrier isolates were significantly less invasive. Using propidium iodide staining and 5-ethynyl-2'-deoxyuridine pulse-labeling, we provide evidence that meningococcal infection arrested cells in the G1 phase of the cell cycle at 24 h postinfection. In parallel, a significant decrease of cells in the S phase was observed. Interestingly, G1-phase arrest was only induced after infection with live bacteria but not with heat-killed bacteria. By Western blotting we demonstrate that bacterial infection resulted in a decreased protein level of the cell cycle regulator cyclin D1, whereas cyclin E expression levels were increased. Furthermore, N. meningitidis infection induced an accumulation of the cyclin-dependent kinase inhibitor (CKI) p21(WAF1/CIP1) that was accompanied by a redistribution of this CKI to the cell nucleus, as shown by immunofluorescence analysis. Moreover, the p27(CIP1) CKI was redistributed and showed punctate foci in infected cells. In summary, we present data that N. meningitidis can interfere with the processes of host cell cycle regulation.


Asunto(s)
Puntos de Control del Ciclo Celular , Células Epiteliales/microbiología , Interacciones Huésped-Patógeno , Infecciones Meningocócicas/microbiología , Neisseria meningitidis/fisiología , Adhesión Bacteriana/fisiología , Western Blotting , Núcleo Celular/metabolismo , Ciclina D1/metabolismo , Ciclina E/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Células Epiteliales/fisiología , Humanos , Infecciones Meningocócicas/metabolismo , Neisseria meningitidis/metabolismo
11.
Ann Oncol ; 26(9): 1923-1929, 2015 09.
Artículo en Inglés | MEDLINE | ID: mdl-26091808

RESUMEN

BACKGROUND: Rigosertib (ON 01910.Na), a first-in-class Ras mimetic and small-molecule inhibitor of multiple signaling pathways including polo-like kinase 1 (PLK1) and phosphoinositide 3-kinase (PI3K), has shown efficacy in preclinical pancreatic cancer models. In this study, rigosertib was assessed in combination with gemcitabine in patients with treatment-naïve metastatic pancreatic adenocarcinoma. MATERIALS AND METHODS: Patients with metastatic pancreatic adenocarcinoma were randomized in a 2:1 fashion to gemcitabine 1000 mg/m(2) weekly for 3 weeks of a 4-week cycle plus rigosertib 1800 mg/m(2) via 2-h continuous IV infusions given twice weekly for 3 weeks of a 4-week cycle (RIG + GEM) versus gemcitabine 1000 mg/m(2) weekly for 3 weeks in a 4-week cycle (GEM). RESULTS: A total of 160 patients were enrolled globally and randomly assigned to RIG + GEM (106 patients) or GEM (54). The most common grade 3 or higher adverse events were neutropenia (8% in the RIG + GEM group versus 6% in the GEM group), hyponatremia (17% versus 4%), and anemia (8% versus 4%). The median overall survival was 6.1 months for RIG + GEM versus 6.4 months for GEM [hazard ratio (HR), 1.24; 95% confidence interval (CI) 0.85-1.81]. The median progression-free survival was 3.4 months for both groups (HR = 0.96; 95% CI 0.68-1.36). The partial response rate was 19% versus 13% for RIG + GEM versus GEM, respectively. Of 64 tumor samples sent for molecular analysis, 47 were adequate for multiplex genetic testing and 41 were positive for mutations. The majority of cases had KRAS gene mutations (40 cases). Other mutations detected included TP53 (13 cases) and PIK3CA (1 case). No correlation between mutational status and efficacy was detected. CONCLUSIONS: The combination of RIG + GEM failed to demonstrate an improvement in survival or response compared with GEM in patients with metastatic pancreatic adenocarcinoma. Rigosertib showed a similar safety profile to that seen in previous trials using the IV formulation.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Glicina/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Sulfonas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/uso terapéutico , Proteínas de Ciclo Celular/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasa Clase I , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Glicina/efectos adversos , Glicina/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasas/genética , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/genética , Sulfonas/efectos adversos , Proteína p53 Supresora de Tumor/genética , Gemcitabina , Quinasa Tipo Polo 1 , Neoplasias Pancreáticas
12.
Phys Rev Lett ; 114(9): 097203, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25793847

RESUMEN

Trivalent americium has a nonmagnetic (J=0) ground state arising from the cancellation of the orbital and spin moments. However, magnetism can be induced by a large molecular field if Am^{3+} is embedded in a ferromagnetic matrix. Using the technique of x-ray magnetic circular dichroism, we show that this is the case in AmFe_{2}. Since ⟨J_{z}⟩=0, the spin component is exactly twice as large as the orbital one, the total Am moment is opposite to that of Fe, and the magnetic dipole operator ⟨T_{z}⟩ can be determined directly; we discuss the progression of the latter across the actinide series.

13.
Phys Rev Lett ; 112(24): 240503, 2014 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-24996074

RESUMEN

Optimal quantum control theory carries a huge promise for quantum technology. Its experimental application, however, is often hindered by imprecise knowledge of the input variables, the quantum system's parameters. We show how to overcome this by adaptive hybrid optimal control, using a protocol named Ad-HOC. This protocol combines open- and closed-loop optimal control by first performing a gradient search towards a near-optimal control pulse and then an experimental fidelity estimation with a gradient-free method. For typical settings in solid-state quantum information processing, adaptive hybrid optimal control enhances gate fidelities by an order of magnitude, making optimal control theory applicable and useful.

14.
Psychol Med ; 44(7): 1511-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23842278

RESUMEN

BACKGROUND: Sleep benefits memory consolidation. Here, we tested the beneficial effect of sleep on memory consolidation following exposure psychotherapy of phobic anxiety. METHOD: A total of 40 individuals afflicted with spider phobia according to DSM-IV underwent a one-session virtual reality exposure treatment and either slept for 90 min or stayed awake afterwards. RESULTS: Sleep following exposure therapy compared with wakefulness led to better reductions in self-reported fear (p = 0.045, d = 0.47) and catastrophic spider-related cognitions (p = 0.026, d = 0.53) during approaching a live spider, both tested after 1 week. Both reductions were associated with greater percentages of stage 2 sleep. CONCLUSIONS: Our results indicate that sleep following successful psychotherapy, such as exposure therapy, improves therapeutic effectiveness, possibly by strengthening new non-fearful memory traces established during therapy. These findings offer an important non-invasive alternative to recent attempts to facilitate therapeutic memory extinction and consolidation processes with pharmacological or behavioral interventions.


Asunto(s)
Terapia Implosiva/métodos , Trastornos Fóbicos/terapia , Sueño/fisiología , Resultado del Tratamiento , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Adulto Joven
15.
Klin Monbl Augenheilkd ; 231(8): 822-9, 2014 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-25133560

RESUMEN

PURPOSE: Endothelial cell damage can be found after a phacoemulsification. The reason for this cell damage is not yet known. The temperature rise inside the anterior chamber during the emulsification of the lens is considered as a potential damage mechanism. The aim of this study was to investigate the relationship between the temperature increase and the cell damage. MATERIALS AND METHODS: This study was performed with 86 enucleated porcine eyes, which were divided into six groups A-F. Group A served as control group. Phacoemulsification was simulated in the groups B-E with different surgically relevant system settings. The temperature change was measured simultaneously with temperature sensors inside the anterior chamber. Inside the eyes of group F, the instruments were positioned and irrigation and aspiration were activated, but no ultrasound was applied. For all 86 corneas, the endothelial cell damage was quantified with a standardised evaluation protocol using scanning electron microscopy (SEM). A potential correlation was checked between the observed cell damage and the measured temperature rise. RESULTS: The highest temperature increase in group E with an obstructed aspiration line and an output power setting of 50 % was 17.77 °C. The temperature increase in group D with an output power setting of 100 % and unblocked fluid flow was significantly lower (p = 0.006). The highest temperature increase in group D was 8.89 °C. In contrast, the cells in group D were rated with a significantly lower score value than the cells in group E (p < 0.001). No significant correlation between the temperature rise and the cell damage could be obtained in due consideration of all measured data. However, an increase of the output power setting was connected with a non-linear increase of the cell loss. CONCLUSION: The temperature rise was not the main reason for the endothelial cell damage in the performed experiments. Therefore, there seems to be no causal relationship between the temperature increase inside the anterior chamber during a common phacoemulsification and the endothelial cell damage. Due to the strong dependence between the output power setting and the cell damage, the lowest output power setting should be used during surgery which ensures the emulsification of the nucleus.


Asunto(s)
Pérdida de Celulas Endoteliales de la Córnea/etiología , Endotelio Corneal/lesiones , Facoemulsificación/efectos adversos , Temperatura , Animales , Pérdida de Celulas Endoteliales de la Córnea/patología , Endotelio Corneal/patología , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Factores de Riesgo , Estadística como Asunto , Porcinos
16.
Artículo en Alemán | MEDLINE | ID: mdl-25296509

RESUMEN

In Germany, the situation of health care services for children and adolescents with gender dysphoria is insufficient. In 2006 a specialized multiprofessional outpatient clinic was founded at the University Medical Center Hamburg-Eppendorf. Goals were improvement of health services for gender dysphoric children, development of treatment concepts, and gain of knowledge through research. After finishing a thorough interdisciplinary assessment an individualized, case-by-case treatment starts. Besides psychotherapy an interdisciplinary treatment (e. g. puberty suppression and cross-sex hormones) is provided if indicated. During childhood a watchful waiting and carefully observing attitude is necessary. If a marked increase of gender dysphoria occurs during the first phases of puberty development, puberty suppression and later cross sex-hormones might be indicated.


Asunto(s)
Conducta Cooperativa , Identidad de Género , Comunicación Interdisciplinaria , Derivación y Consulta , Transexualidad/terapia , Adolescente , Investigación Biomédica , Niño , Terapia Combinada , Educación no Profesional , Femenino , Hormonas Esteroides Gonadales/uso terapéutico , Humanos , Masculino , Servicio Ambulatorio en Hospital , Psicoterapia , Pubertad/efectos de los fármacos , Pubertad/psicología , Transexualidad/diagnóstico , Transexualidad/psicología , Espera Vigilante
17.
Phys Rev Lett ; 111(16): 163601, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-24182265

RESUMEN

Quantum transmission lines are central to superconducting and hybrid quantum computing. In this work we show how coupling them to a left-handed transmission line allows circuit QED to reach a new regime: multimode ultrastrong coupling. Out of the many potential applications of this novel device, we discuss the preparation of multipartite entangled states and the simulation of the spin-boson model where a quantum phase transition is reached up to finite size effects.

18.
Phys Rev Lett ; 111(16): 167206, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-24182299

RESUMEN

Europium nitride is semiconducting and contains nonmagnetic Eu3+, but substoichiometric EuN has Eu in a mix of 2+ and 3+ charge states. We show that at Eu2+ concentrations near 15%-20% EuN is ferromagnetic with a Curie temperature as high as 120 K. The Eu3+ polarization follows that of the Eu2+, confirming that the ferromagnetism is intrinsic to the EuN which is, thus, a novel diluted magnetic semiconductor. Transport measurements shed light on the likely exchange mechanisms.

19.
Phys Rev Lett ; 109(19): 197204, 2012 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-23215422

RESUMEN

The magnetic moment induced on Rh atoms, forming 1.6 nm average diameter clusters, embedded in an Al(2)O(3) matrix, has been determined using x-ray magnetic circular dichroism measurements. The magnetic moment varies linearly with the applied magnetic field. At 2.3 K and under 17 T, the spin magnetic moment amounts to 0.067(2) µ(B)/Rh atom. The orbital moment does not exceed 2% of the spin moment. The susceptibility is highly temperature dependent. This is in agreement with a prediction due to Moriya and Kawabata, that in itinerant electron systems, close to the onset of magnetism, the renormalization of the magnetic susceptibility by electron correlations, leads to a Curie-like behavior.


Asunto(s)
Dicroismo Circular/métodos , Rodio/química , Óxido de Aluminio/química , Campos Electromagnéticos
20.
Phys Rev Lett ; 109(24): 247203, 2012 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-23368371

RESUMEN

Magnetic properties of Au nanoparticles deposited on an archaeal S layer are reported. X-ray magnetic circular dichroism and superconducting quantum interference device magnetometries demonstrate that the particles are strongly paramagnetic, without any indication of magnetic blocking down to 16 mK. The average magnetic moment per particle is M(part)=2.36(7) µ(B). This contribution originates at the particle's Au 5d band, in which an increased number of holes with respect to the bulk value is observed. The magnetic moment per Au atom is 25 times larger than any measured in other Au nanoparticles or any other configurations up to date.

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