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1.
Australas Psychiatry ; 31(5): 619-624, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37473424

RESUMEN

OBJECTIVE: Deliberate foreign body ingestion (DFBI) is characterised by recurrent presentations among patients with mental health conditions, intellectual disabilities and in prisoners. We aimed to profile the characteristics and evaluate the care of such patients in this study. METHODS: Adult patients with an endoscopic record of attempted foreign body retrieval between January 2013 and September 2020 were identified at three Australian hospitals. Those with a documented mental health diagnosis were included and their standard medical records reviewed. Presentation history, demographics, comorbidities and endoscopic findings were recorded and described. RESULTS: A total of 166 admissions were accounted for by 35 patients, 2/3 of which had borderline personality disorder (BPD). Repetitive presentations occurred in more than half of the cohort. There was an increased trend of hospital admissions throughout the years. At least half of the cohort had a documented mental health review during their admission. An average of 3.3 (2.9) foreign bodies were ingested per single episode. Endoscopic intervention was performed in 76.5% of incidents. The combined Length of stay for all patients was 680 days. CONCLUSION: Deliberate foreign body ingestion in mental health patients is a common, recurring and challenging problem that is increasing in frequency and requires collaborative research to further guide holistic management.


Asunto(s)
Cuerpos Extraños , Trastornos Mentales , Adulto , Humanos , Australia/epidemiología , Trastornos Mentales/epidemiología , Trastornos Mentales/terapia , Estudios Retrospectivos , Ingestión de Alimentos , Cuerpos Extraños/epidemiología , Cuerpos Extraños/terapia
2.
Nature ; 530(7591): 461-4, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26855424

RESUMEN

The non-equilibrium control of emergent phenomena in solids is an important research frontier, encompassing effects such as the optical enhancement of superconductivity. Nonlinear excitation of certain phonons in bilayer copper oxides was recently shown to induce superconducting-like optical properties at temperatures far greater than the superconducting transition temperature, Tc (refs 4-6). This effect was accompanied by the disruption of competing charge-density-wave correlations, which explained some but not all of the experimental results. Here we report a similar phenomenon in a very different compound, K3C60. By exciting metallic K3C60 with mid-infrared optical pulses, we induce a large increase in carrier mobility, accompanied by the opening of a gap in the optical conductivity. These same signatures are observed at equilibrium when cooling metallic K3C60 below Tc (20 kelvin). Although optical techniques alone cannot unequivocally identify non-equilibrium high-temperature superconductivity, we propose this as a possible explanation of our results.

3.
Nat Mater ; 14(9): 883-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26147844

RESUMEN

Static strain in complex oxide heterostructures has been extensively used to engineer electronic and magnetic properties at equilibrium. In the same spirit, deformations of the crystal lattice with light may be used to achieve functional control across heterointerfaces dynamically. Here, by exciting large-amplitude infrared-active vibrations in a LaAlO3 substrate we induce magnetic order melting in a NdNiO3 film across a heterointerface. Femtosecond resonant soft X-ray diffraction is used to determine the spatiotemporal evolution of the magnetic disordering. We observe a magnetic melt front that propagates from the substrate interface into the film, at a speed that suggests electronically driven motion. Light control and ultrafast phase front propagation at heterointerfaces may lead to new opportunities in optomagnetism, for example by driving domain wall motion to transport information across suitably designed devices.

4.
Phys Rev Lett ; 116(24): 240402, 2016 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-27367366

RESUMEN

We investigate cold bosonic impurity atoms trapped in a vortex lattice formed by condensed bosons of another species. We describe the dynamics of the impurities by a bosonic Hubbard model containing occupation-dependent parameters to capture the effects of strong impurity-impurity interactions. These include both a repulsive direct interaction and an attractive effective interaction mediated by the Bose-Einstein condensate. The occupation dependence of these two competing interactions drastically affects the Hubbard model phase diagram, including causing the disappearance of some Mott lobes.

5.
Phys Rev Lett ; 114(13): 137001, 2015 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-25884134

RESUMEN

We propose and analyze a scheme for parametrically cooling bilayer cuprates based on the selective driving of a c-axis vibrational mode. The scheme exploits the vibration as a transducer making the Josephson plasma frequencies time dependent. We show how modulation at the difference frequency between the intrabilayer and interbilayer plasmon substantially suppresses interbilayer phase fluctuations, responsible for switching c-axis transport from a superconducting to a resistive state. Our calculations indicate that this may provide a viable mechanism for stabilizing nonequilibrium superconductivity even above Tc, provided a finite pair density survives between the bilayers out of equilibrium.

6.
Phys Rev Lett ; 114(9): 090602, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25793792

RESUMEN

Estimating the expected value of an observable appearing in a nonequilibrium stochastic process usually involves sampling. If the observable's variance is high, many samples are required. In contrast, we show that performing the same task without sampling, using tensor network compression, efficiently captures high variances in systems of various geometries and dimensions. We provide examples for which matching the accuracy of our efficient method would require a sample size scaling exponentially with system size. In particular, the high-variance observable e^{-ßW}, motivated by Jarzynski's equality, with W the work done quenching from equilibrium at inverse temperature ß, is exactly and efficiently captured by tensor networks.

7.
Phys Rev Lett ; 115(18): 187401, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26565494

RESUMEN

We use midinfrared pulses with stable carrier-envelope phase offset to drive molecular vibrations in the charge transfer salt ET-F_{2}TCNQ, a prototypical one-dimensional Mott insulator. We find that the Mott gap, which is probed resonantly with 10 fs laser pulses, oscillates with the pump field. This observation reveals that molecular excitations can coherently perturb the electronic on-site interactions (Hubbard U) by changing the local orbital wave function. The gap oscillates at twice the frequency of the vibrational mode, indicating that the molecular distortions couple quadratically to the local charge density.

8.
Phys Rev Lett ; 112(11): 117801, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24702420

RESUMEN

We measure the ultrafast recombination of photoexcited quasiparticles (holon-doublon pairs) in the one dimensional Mott insulator ET-F(2)TCNQ as a function of external pressure, which is used to tune the electronic structure. At each pressure value, we first fit the static optical properties and extract the electronic bandwidth t and the intersite correlation energy V. We then measure the recombination times as a function of pressure, and we correlate them with the corresponding microscopic parameters. We find that the recombination times scale differently than for metals and semiconductors. A fit to our data based on the time-dependent extended Hubbard Hamiltonian suggests that the competition between local recombination and delocalization of the Mott-Hubbard exciton dictates the efficiency of the recombination.


Asunto(s)
Compuestos Heterocíclicos/química , Modelos Químicos , Nitrilos/química , Fleroxacino/análogos & derivados , Fleroxacino/química , Óptica y Fotónica , Presión
9.
Phys Rev Lett ; 110(23): 230601, 2013 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-25167476

RESUMEN

We propose an experimental scheme to verify the quantum nonequilibrium fluctuation relations using current technology. Specifically, we show that the characteristic function of the work distribution for a nonequilibrium quench of a general quantum system can be extracted by Ramsey interferometry of a single probe qubit. Our scheme paves the way for the full characterization of nonequilibrium processes in a variety of quantum systems, ranging from single particles to many-body atomic systems and spin chains. We demonstrate our idea using a time-dependent quench of the motional state of a trapped ion, where the internal pseudospin provides a convenient probe qubit.

10.
Arch Biochem Biophys ; 533(1-2): 55-61, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23500138

RESUMEN

Platelet activation represents a key event in normal hemostasis as well as during platelet plug formation related to thrombosis. Nitro-fatty acids are novel endogenously produced signaling mediators exerting pluripotent anti-inflammatory actions in cells and tissues. We have recently shown that nitroarachidonic acid inhibits thromboxane synthesis during platelet activation by affecting prostaglandin endoperoxide H synthase (PGHS). Herein, we investigated the regulation of human platelet activation by NO(2)AA and describe a novel mechanism involving protein kinase C (PKC) inhibition. NO(2)AA-mediated antiplatelet effects were characterized using mass spectrometry, confocal microscopy, flow cytometry, western blot and aggregometry. Incubation of NO(2)AA with human platelets caused a significant reduction in platelet sensitivity to thrombin, ADP, arachidonic acid (AA), and phorbol ester (PMA). These effects were cGMP-independent and did not involve Ca(2+) store-dependent mobilization. In contrast, signaling downstream of conventional PKC activation, such as α-granule secretion and extracellular signal regulated kinase 2 activation was strongly inhibited by NO(2)AA. Immunofluorescence confocal microscopy confirmed NO(2)AA-mediated inhibition of PKCα translocation to the membrane. In summary, we demonstrate that NO(2)AA inhibits platelet activation through modulation of PKCα activity as a potential novel mechanism for platelet regulation in vivo.


Asunto(s)
Ácido Araquidónico/farmacología , Activación Plaquetaria/efectos de los fármacos , Proteína Quinasa C/metabolismo , Animales , Ácido Araquidónico/metabolismo , Transporte Biológico , Bovinos , Humanos , Agregación Plaquetaria/efectos de los fármacos
11.
Sci Rep ; 6: 32940, 2016 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-27609673

RESUMEN

We propose a non-linear, hybrid quantum-classical scheme for simulating non-equilibrium dynamics of strongly correlated fermions described by the Hubbard model in a Bethe lattice in the thermodynamic limit. Our scheme implements non-equilibrium dynamical mean field theory (DMFT) and uses a digital quantum simulator to solve a quantum impurity problem whose parameters are iterated to self-consistency via a classically computed feedback loop where quantum gate errors can be partly accounted for. We analyse the performance of the scheme in an example case.

12.
Nat Phys ; 12(11): 1012-1016, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27833647

RESUMEN

Many applications in photonics require all-optical manipulation of plasma waves1, which can concentrate electromagnetic energy on sub-wavelength length scales. This is difficult in metallic plasmas because of their small optical nonlinearities. Some layered superconductors support Josephson plasma waves (JPWs)2,3, involving oscillatory tunneling of the superfluid between capacitively coupled planes. Josephson plasma waves are also highly nonlinear4, and exhibit striking phenomena like cooperative emission of coherent terahertz radiation5,6, superconductor-metal oscillations7 and soliton formation8. We show here that terahertz JPWs can be parametrically amplified through the cubic tunneling nonlinearity in a cuprate superconductor. Parametric amplification is sensitive to the relative phase between pump and seed waves and may be optimized to achieve squeezing of the order parameter phase fluctuations9 or single terahertz-photon devices.

13.
Transl Psychiatry ; 6(9): e897, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27648919

RESUMEN

Current criteria identifying patients with ultra-high risk of psychosis (UHR) have low specificity, and less than one-third of UHR cases experience transition to psychosis within 3 years of initial assessment. We explored whether a Bayesian probabilistic multimodal model, combining baseline historical and clinical risk factors with biomarkers (oxidative stress, cell membrane fatty acids, resting quantitative electroencephalography (qEEG)), could improve this specificity. We analyzed data of a UHR cohort (n=40) with a 1-year transition rate of 28%. Positive and negative likelihood ratios were calculated for predictor variables with statistically significant receiver operating characteristic curves (ROCs), which excluded oxidative stress markers and qEEG parameters as significant predictors of transition. We clustered significant variables into historical (history of drug use), clinical (Positive and Negative Symptoms Scale positive, negative and general scores and Global Assessment of Function) and biomarker (total omega-3, nervonic acid) groups, and calculated the post-test probability of transition for each group and for group combinations using the odds ratio form of Bayes' rule. Combination of the three variable groups vastly improved the specificity of prediction (area under ROC=0.919, sensitivity=72.73%, specificity=96.43%). In this sample, our model identified over 70% of UHR patients who transitioned within 1 year, compared with 28% identified by standard UHR criteria. The model classified 77% of cases as very high or low risk (P>0.9, <0.1) based on history and clinical assessment, suggesting that a staged approach could be most efficient, reserving fatty-acid markers for 23% of cases remaining at intermediate probability following bedside interview.


Asunto(s)
Trastorno Bipolar/psicología , Síntomas Prodrómicos , Trastornos Psicóticos/psicología , Esquizofrenia Paranoide/psicología , Adolescente , Teorema de Bayes , Trastorno Bipolar/metabolismo , Trastorno Bipolar/fisiopatología , Niño , Estudios de Cohortes , Progresión de la Enfermedad , Electroencefalografía , Ácidos Grasos/metabolismo , Femenino , Humanos , Masculino , Lípidos de la Membrana/metabolismo , Oportunidad Relativa , Estrés Oxidativo , Probabilidad , Trastornos Psicóticos/metabolismo , Trastornos Psicóticos/fisiopatología , Curva ROC , Riesgo , Medición de Riesgo , Esquizofrenia Paranoide/metabolismo , Esquizofrenia Paranoide/fisiopatología , Adulto Joven
14.
Artículo en Inglés | MEDLINE | ID: mdl-25974460

RESUMEN

In this work we analyze the simultaneous emergence of diffusive energy transport and local thermalization in a nonequilibrium one-dimensional quantum system, as a result of integrability breaking. Specifically, we discuss the local properties of the steady state induced by thermal boundary driving in a XXZ spin chain with staggered magnetic field. By means of efficient large-scale matrix product simulations of the equation of motion of the system, we calculate its steady state in the long-time limit. We start by discussing the energy transport supported by the system, finding it to be ballistic in the integrable limit and diffusive when the staggered field is finite. Subsequently, we examine the reduced density operators of neighboring sites and find that for large systems they are well approximated by local thermal states of the underlying Hamiltonian in the nonintegrable regime, even for weak staggered fields. In the integrable limit, on the other hand, this behavior is lost, and the identification of local temperatures is no longer possible. Our results agree with the intuitive connection between energy diffusion and thermalization.

15.
Surgery ; 105(6): 790-2, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2658182

RESUMEN

We describe a case of incarcerated rectal prolapse caused by blunt abdominal trauma. Emergency treatment consisted of manual reduction with the patient under general anesthesia, proctosigmoidoscopy, and peritoneal lavage. Subsequent definitive surgical therapy was then performed after bowel preparation and consisted of anterior resection of the sigmoid colon with posterior (sacral) rectopexy.


Asunto(s)
Traumatismos Abdominales/complicaciones , Prolapso Rectal/etiología , Heridas no Penetrantes/complicaciones , Traumatismos Abdominales/terapia , Accidentes de Tránsito , Enfermedad Aguda , Adulto , Colon Sigmoide/cirugía , Urgencias Médicas , Humanos , Masculino , Prolapso Rectal/terapia , Recto/cirugía
16.
Health Technol Assess ; 1(9): i-iv, 1-65, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9483158

RESUMEN

BACKGROUND: Health technology assesment (HTA) requires scientifically rigorous experimentation involving patients as subjects. HTA itself is required so that treatment given to patients will be both effective and efficient; this requirement is itself ethical in nature. At the same time it is essential that the methods used in HTA are ethically sound. Most healthcare researchers agree that the most effective and soundest method for assessing treatments is the randomised controlled trial (RCT). However, some researchers believe that the RCT is unethical, either in essence, or for use in some forms of medical research and HTA. Furthermore, many patients seem unable to understand the principles and purposes of the RCT, a factor which is highly detrimental for the validity of informed consent. Informed consent is the key to the ethics of medical research, both in most theories and in all codes of research conduct. Many RCTs therefore risk being unethical in practice, even if ethical in principle. AIM OF REPORT: To survey the main objections to the RCT and its alternatives. To assess the philosophical and methodological basis of these objections, and of the methods recommended for addressing them. To identify areas where objections are founded in social or cultural factors normally overlooked in ethical argument about the RCT methodology. To identify alternative arguments or methods which might resolve ethical conflicts in this area. HOW THE RESEARCH WAS CONDUCTED: The methods used were adapted from systematic reviews in medicine. Systematic searches of Medline, Psychlit and Sociofile CD-ROM databases; hand-searches of the major journals in general medicine and surgery, medical ethics and philosophy; and searches of books were carried out. The literature survey was restricted to articles published or abstracted in English. A database of the most relevant and useful materials was compiled, and is accessible on the Internet (http://www.liv.ac.uk/sdthomps/page1.html). RESEARCH FINDINGS: UNDERSTANDING RCTS AND THEIR ALTERNATIVES: There is some evidence of difficulty in understanding the aims and methods of RCTs, and some disquiet about elements of the RCT methodologies. These objections are well known and much discussed, and concern the use of placebo, the continuation of trials after significant differentials in benefit or harm are apparent, and randomisation. CULTURAL OR RELIGIOUS OBJECTIONS: There was an absence of evidence of cultural or religious objections to randomisation, placebo or other kinds of controlled prospective trials. This most likely reflects an absence of research rather than absence of objections. (ABSTRACT TRUNCATED)


Asunto(s)
Diversidad Cultural , Ética Médica , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Femenino , Humanos , Consentimiento Informado , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Proyectos de Investigación , Factores Socioeconómicos , Reino Unido
17.
Arthritis Care Res ; 5(4): 216-22, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1489768

RESUMEN

Two studies were conducted to characterize the pain of fibromyalgia syndrome (FMS); to compare it to rheumatoid arthritis (RA) pain; and to examine the relationships between depression, pain extent, and pain description. Two methods of administering the McGill Pain Questionnaire (MPQ) were used. When the MPQ was administered in the standard manner, FMS pain could not be distinguished from RA pain. When participants were allowed to select as many words from an adapted MPQ as they wished, significant differences in word choice emerged. Depression and pain extent were major predictors of group differences in the evaluation of pain. However, depression scores contributed only 50% of the explanation for the differences in pain extent, with group membership contributing the other 50%. These findings suggest that the character and extent of pain in FMS are at least partially due to peripheral sensory components and not simply centrally controlled pain amplification secondary to depression.


Asunto(s)
Artritis Reumatoide/complicaciones , Trastorno Depresivo/psicología , Fibromialgia/complicaciones , Dolor/psicología , Adulto , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/etiología , Femenino , Humanos , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/etiología , Dimensión del Dolor , Índice de Severidad de la Enfermedad
18.
Arthritis Care Res ; 7(1): 35-9, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7918724

RESUMEN

PURPOSE: This study investigated the relationships among four methods of detecting depression in patients with fibromyalgia. METHODS: Data were obtained from 100 women (mean age 43 years) who had been diagnosed with fibromyalgia. Instruments included a computerized Diagnostic Interview Schedule (C-DIS), Beck Depression Inventory (BDI), an adjusted "disease-free" BDI (BDI-A), and Minnesota Multiphasic Personality Inventory depression subscale (MMPI-D). Chance-corrected concordance, sensitivity, specificity, and accuracy among the four methods were calculated. RESULTS: The C-DIS detected 22% and BDI-A 29% with current major depression. The BDI and MMPI-D yielded higher estimates of 55% of the 44%, respectively. Agreement on the diagnosis among the four methods was significantly greater than chance. When compared with the C-DIS, the BDI was the most sensitive instrument and the BDI-A most specific.


Asunto(s)
Trastorno Depresivo/diagnóstico , Trastorno Depresivo/etiología , Fibromialgia/psicología , Adulto , Anciano , Trastorno Depresivo/epidemiología , Femenino , Fibromialgia/complicaciones , Humanos , MMPI , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Am J Surg ; 161(4): 479-81; discussion 482, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2035768

RESUMEN

Fibrin glue made with highly concentrated human fibrinogen and clotting factors was evaluated as a means of preventing pancreatic fistulas in 15 patients operated on for traumatic and nontraumatic conditions. Fibrin glue was applied directly to penetrating pancreatic injuries, pancreatic suture and staple lines in patients treated by partial resection, and pancreaticointestinal anastomoses. Postoperatively, no patient developed pancreatic fistulas, pancreatic abscesses, or pseudocysts. Fibrin glue sealing of pancreatic injuries, resections, and anastomoses may aid in preventing fistulas after pancreatic surgery. Additional potential uses include the sealing of pancreatic biopsy sites and occlusion of the pancreatic duct in pancreatic transplantation.


Asunto(s)
Adhesivo de Tejido de Fibrina/uso terapéutico , Páncreas/lesiones , Páncreas/cirugía , Fístula Pancreática/prevención & control , Anastomosis Quirúrgica , Humanos , Cuidados Intraoperatorios , Pancreatectomía , Pancreatoyeyunostomía , Pancreatitis/cirugía , Engrapadoras Quirúrgicas , Suturas
20.
Am Surg ; 58(5): 293-4, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1622009

RESUMEN

This article describes four patients with perforated gastroduodenal ulcers related to smoking "crack" cocaine. All patients came to the hospital with acute abdominal pain; only one patient had a history of ulcer disease. Only one patient had an elevated white blood cell count, and two patients had depressed white blood cell counts. In three patients, the x ray showed that pneumoperitoneum was present. Upon surgical exploration of the abdomen, all patients were found to have extensive peritoneal contamination. Operative repair consisted of omental patching with or without primary closure of the perforation. A history of cocaine smoking should be sought in patients with unexplained abdominal pain or pneumoperitoneum. In patients with acute abdominal pain and a history of smoking cocaine, a perforated gastroduodenal ulcer may be present, despite normal or low white blood cell counts and the lack of pneumoperitoneum on x-ray examination.


Asunto(s)
Cocaína Crack , Úlcera Duodenal/complicaciones , Úlcera Péptica Perforada/etiología , Úlcera Gástrica/complicaciones , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Femenino , Humanos , Recuento de Leucocitos , Masculino , Anamnesis/normas , Persona de Mediana Edad , Úlcera Péptica Perforada/diagnóstico , Úlcera Péptica Perforada/cirugía , Neumoperitoneo/diagnóstico por imagen , Neumoperitoneo/etiología , Radiografía , Trastornos Relacionados con Sustancias/diagnóstico
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