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1.
Vet J ; 281: 105801, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35150842

RESUMO

Breed specific paroxysmal dyskinesias are increasingly recognised in veterinary medicine. We aimed to characterise the phenomenology, clinical course and prevalence of a previously unreported paroxysmal dyskinesia in the Welsh terrier breed. Clinical records of five Welsh terriers with paroxysmal episodes were reviewed. Additionally, owners of Welsh terriers were invited to complete a questionnaire with the aim of characterising paroxysmal episodes in the wider breed population. Clinical examinations (n = 5) and diagnostic investigations (n = 3) of affected Welsh terriers were within normal limits, apart from mild-moderate ventriculomegaly on cranial magnetic resonance imaging (n = 3). The survey of Welsh terrier owners revealed episodes consistent with a paroxysmal dyskinesia in 41 (22.8%) of 177 respondents. Median age of onset was 59 months. Episodes were predominantly characterised by sustained hypertonicity with periods of limb flexion, abnormal head and body posture, with preserved consciousness. Episode duration ranged from 30 s to 30 min (median, 3 min 30 s), with frequency varying widely between dogs. Affected dogs demonstrated a stable to improving clinical course in most cases. This study investigated a previously unreported paroxysmal dyskinesia in Welsh terriers. Similar clinical signs within the breed were potentially consistent with an inherited cause, worthy of further investigation.


Assuntos
Coreia , Doenças do Cão , Animais , Coreia/genética , Coreia/veterinária , Doenças do Cão/diagnóstico , Cães
2.
Ann R Coll Surg Engl ; 103(9): e269-e271, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34019457

RESUMO

Thoracic chest wall trauma is a common injury in patients admitted to hospital following injury and is associated with high mortality. British Orthopaedic Association Standards for Trauma and Orthopaedics guidelines recommend consideration of rib fracture fixation in patients with flail chest wall injuries with respiratory compromise or uncontrollable pain. Veno-venous extracorporeal membrane oxygenation (ECMO) can be utilised in patients with severe respiratory dysfunction and we present the case of a patient who underwent rib fracture fixation while receiving ECMO. A 32-year-old male was admitted to our department following a 4.5m fall. He sustained significant thoracic injuries with multiple ribs fractures and a flail segment from the right fourth to ninth ribs. Treatment consisted of bilateral chest drains, ECMO support, tracheostomy and rib fracture fixation to the eighth and ninth ribs. The patient made a rapid recovery following surgery and ECMO support was ceased 2.5 days postoperatively. The case shows that a well-prepared, combined specialty surgical team can safely perform rib fixation for a patient on ECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Fixação de Fratura , Fraturas das Costelas/cirurgia , Traumatismos Torácicos/terapia , Ferimentos não Penetrantes/terapia , Adulto , Humanos , Escala de Gravidade do Ferimento , Masculino , Fraturas das Costelas/complicações , Traumatismos Torácicos/complicações , Ferimentos não Penetrantes/complicações
3.
Phys Rev Lett ; 121(2): 020404, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30085750

RESUMO

We present a theoretical investigation of the properties of quantum correlation functions in a multimode system. We define a total mth order equal-time correlation function, summed over all modes, which is shown to be conserved if the Hamiltonian possesses U(1) symmetry. It is also conserved in the presence of dissipation, provided the loss rate is the same for all modes of the system. As examples, we demonstrate this conservation using numerical simulations of a coupled cavity system and the Jaynes-Cummings model.

4.
Phys Rev Lett ; 120(9): 097401, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29547302

RESUMO

We study exciton polaritons in a two-dimensional Lieb lattice of micropillars. The energy spectrum of the system features two flat bands formed from S and P_{x,y} photonic orbitals, into which we trigger bosonic condensation under high power excitation. The symmetry of the orbital wave functions combined with photonic spin-orbit coupling gives rise to emission patterns with pseudospin texture in the flat band condensates. Our Letter shows the potential of polariton lattices for emulating flat band Hamiltonians with spin-orbit coupling, orbital degrees of freedom, and interactions.

7.
Phys Rev Lett ; 116(11): 116402, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-27035313

RESUMO

We report the experimental investigation and theoretical modeling of a rotating polariton superfluid relying on an innovative method for the injection of angular momentum. This novel, multipump injection method uses four coherent lasers arranged in a square, resonantly creating four polariton populations propagating inwards. The control available over the direction of propagation of the superflows allows injecting a controllable nonquantized amount of optical angular momentum. When the density at the center is low enough to neglect polariton-polariton interactions, optical singularities, associated with an interference pattern, are visible in the phase. In the superfluid regime resulting from the strong nonlinear polariton-polariton interaction, the interference pattern disappears and only vortices with the same sign are persisting in the system. Remarkably, the number of vortices inside the superfluid region can be controlled by controlling the angular momentum injected by the pumps.

8.
Phys Rev Lett ; 115(24): 246401, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26705642

RESUMO

We report an extended family of spin textures of zero-dimensional exciton-polaritons spatially confined in tunable open microcavity structures. The transverse-electric-transverse-magnetic (TE-TM) splitting, which is enhanced in the open cavity structures, leads to polariton eigenstates carrying quantized spin vortices. Depending on the strength and anisotropy of the cavity confining potential and of the TE-TM induced splitting, which can be tuned via the excitonic or photonic fractions, the exciton-polariton emissions exhibit either spin-vortex-like patterns or linear polarization, in good agreement with theoretical modeling.

9.
Nutr Res ; 34(7): 577-84, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25150116

RESUMO

Evidence suggests that berries contain bioactive compounds, which reduce certain cancers and hypertension. Our hypothesis was that daily blueberry (BB) consumption would increase natural killer (NK) cells and plasma redox capacity and reduce blood pressure, augmentation index (AIx), central pulse wave velocity, and aortic systolic pressures (ASPs). Twenty-five men and postmenopausal women aged 18 to 50 years were recruited and randomized to BB (n, 13) or placebo groups (n, 12). Participants were provided with BB (equivalent to 250 g berries) or placebo powders each day for 6 weeks. Blood pressure, vascular performance testing, and blood samples were taken at baseline (presupplementation). Participants returned after 6 weeks and repeated all procedures. Presupplementation to postsupplementation comparisons for the main effects of treatment, time, and treatment-time interaction were made using a 2 (treatment) × 2 (times) repeated-measures analysis of variance for all vascular measures, redox status, and NK cell counts. Anthropometric measures were compared using t tests. Body mass, composition, and overall blood pressures were not affected in either group. Overall, AIx and ASPs were decreased in BB (treatment effect, P = .024 and P = .046, respectively). Plasma redox was not affected. Absolute NK cells were increased in BB (time, P = .001 and interaction, P = .012). Subjects (n, 9) with prehypertensive pressures (≥120/80 mm Hg, respectively) were examined as a subset using t tests and exhibited significant reductions in diastolic pressure (P = .038) from presupplementation to postsupplementation in BB. We conclude that BB ingestion for 6 weeks increases NK cells and reduces AIx, ASP, and diastolic pressures in sedentary males and females.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Mirtilos Azuis (Planta) , Células Matadoras Naturais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pré-Hipertensão , Rigidez Vascular/efeitos dos fármacos , Adolescente , Adulto , Aorta , Suplementos Nutricionais , Exercício Físico , Feminino , Frutas , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Oxirredução , Fitoterapia , Extratos Vegetais/uso terapêutico , Pré-Hipertensão/tratamento farmacológico , Pré-Hipertensão/fisiopatologia , Comportamento Sedentário , Adulto Jovem
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(2 Pt 2): 026406, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23005868

RESUMO

The accurate characterization of thermal electron transport and the determination of heating by suprathermal electrons in laser driven solid targets are both issues of great importance to the current experiments being performed at the National Ignition Facility, which aims to achieve thermonuclear fusion ignition using lasers. Ionization, induced by electronic heat conduction, can cause the opacity of a material to drop significantly once bound-free photoionization is no longer energetically possible. We show that this drop in opacity enables measurements of the transmission of extreme ultraviolet (EUV) laser pulses at 13.9 nm to act as a signature of the heating of thin (50 nm) iron layers with a 50-nm thick parylene-N (CH) overlay irradiated by 35-fs pulses at irradiance 3×10(16) Wcm(-2). Comparing EUV transmission measurements at different times after irradiation to fluid code simulations shows that the target is instantaneously heated by hot electrons (with approximately 10% of the laser energy), followed by thermal conduction with a flux limiter of ≈0.05.

11.
Surgeon ; 10(3): 172-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22405735

RESUMO

BACKGROUND: Bariatric surgery can provide efficient weight loss and improvement in obesity-related co-morbidities in adults. Laparoscopic adjustable gastric banding (LAGB) comprised 30.3% of all bariatric procedures between 2009 and 2010 in the UK. This review evaluates the level 1 evidence for change in co-morbidities, quality of life (QoL) and weight provided by LAGB compared with other bariatric procedures. METHOD: Systematic literature search of MEDLINE, EMBASE and CENTRAL (1988 to May 2011) was performed. Only randomised controlled trials (RCTs) were included. Studies with non-surgical comparators, open gastric banding procedures or adolescent participants were excluded. Primary outcome was change in co-morbidities. Secondary outcomes included QoL, weight loss, complications, operation time and length of stay. RESULTS: Five RCTs met the inclusion criteria. Vertical banded gastroplasty, sleeve gastrectomy and gastric bypass were compared to LAGB. Co-morbidities were reported in two studies and QoL in one. LAGB was comparable to other procedures for both of these outcomes. All five trials showed LABG to be effective in weight loss, however all comparative procedures resulted in greater weight loss. Operative time and length of hospital stay were significantly shorter with LAGB. Short-term complications were found to be consistently lower in the LAGB group. Evidence was divided with respect to long-term complications. CONCLUSION: Co-morbidities and QoL are poorly reported and showed no difference between LAGB and other bariatric procedures. Evidence suggests that LAGB is not the most effective surgical procedure to reduce weight. LAGB is associated with lower early complications and shorter operative time and length of stay, and therefore may be preferable to patients.


Assuntos
Índice de Massa Corporal , Gastroplastia/métodos , Laparoscopia/métodos , Obesidade Mórbida/cirurgia , Qualidade de Vida , Adulto , Feminino , Derivação Gástrica/efeitos adversos , Derivação Gástrica/métodos , Gastroplastia/efeitos adversos , Humanos , Derivação Jejunoileal/efeitos adversos , Derivação Jejunoileal/métodos , Laparoscopia/efeitos adversos , Pessoa de Meia-Idade , Obesidade Mórbida/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Resultado do Tratamento , Redução de Peso
12.
Opt Express ; 19(6): 5670-5, 2011 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-21445207

RESUMO

We investigate the energy splitting, quality factor and polarization of the fundamental modes of coupled L3 photonic crystal cavities. Four different geometries are evaluated theoretically, before experimentally investigating coupling in a direction at 30◦ to the line of the cavities. In this geometry, a smooth variation of the energy splitting with the cavity separation is predicted and observed, together with significant differences between the polarizations of the bonding and anti-bonding states. The controlled splitting of the coupled states is potentially useful for applications that require simultaneous resonant enhancement of two transitions.

13.
Opt Lett ; 35(22): 3820-2, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21082008

RESUMO

We demonstrate that interferometric probing with extreme ultraviolet (EUV) laser light enables determination of the degree of ionization of the "warm dense matter" produced between the critical and ablation surfaces of laser plasmas. Interferometry has been utilized to measure both transmission and phase information for an EUV laser beam at the photon energy of 58.5 eV, probing longitudinally through laser-irradiated plastic (parylene-N) targets (thickness 350 nm) irradiated by a 300 ps duration pulse of wavelength 438 nm and peak irradiance 10(12) W cm(-2). The transmission of the EUV probe beam provides a measure of the rate of target ablation, as ablated plasma becomes close to transparent when the photon energy is less than the ionization energy of the predominant ion species. We show that refractive indices η below the solid parylene N (η(solid) = 0.946) and expected plasma values are produced in the warm dense plasma created by laser irradiation due to bound-free absorption in C(+).

14.
J Acoust Soc Am ; 128(3): 1149-54, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20815451

RESUMO

A numerical investigation is performed into the diffusive effects of cylinders positioned in front of a Schroeder diffuser. A regular line of cylinders is shown to offer notable improvements to diffusion from a periodic Schroeder device, provided lateral cylinder spacing is incommensurable with the Schroeder period width. Further investigation considers angular dependence and low frequency results in greater detail, as well as the effects on narrowband and modulated Schroeder devices. An optimization procedure is subsequently performed to investigate the effects of an irregular cylinder arrangement, which provides further diffusive benefits.


Assuntos
Acústica/instrumentação , Arquitetura de Instituições de Saúde , Simulação por Computador , Difusão , Desenho de Equipamento , Modelos Teóricos , Análise Numérica Assistida por Computador , Som
15.
Phys Rev Lett ; 105(6): 063902, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20867980

RESUMO

We study nonequilibrium polariton superfluids in the optical-parametric-oscillator regime by using a Gross-Pitaevskii equation with pumping and decay. We identify a regime above the optical-parametric-oscillator threshold, where the system undergoes spontaneous symmetry breaking and is unstable towards vortex formation without any rotating drive. Stable vortex solutions differ from metastable ones; the latter can persist but can be triggered only externally. Both spontaneous and triggered vortices are characterized by a generalized healing length, specified by the optical-parametric-oscillator parameters only.

16.
Phys Rev Lett ; 104(12): 126402, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-20366553

RESUMO

We demonstrate the creation of vortices in a macroscopically occupied polariton state formed in a semiconductor microcavity. A weak external laser beam carrying orbital angular momentum (OAM) is used to imprint a vortex on the condensate arising from the polariton optical parametric oscillator (OPO). The vortex core radius is found to decrease with increasing pump power, and is determined by polariton-polariton interactions. As a result of OAM conservation in the parametric scattering process, the excitation consists of a vortex in the signal and a corresponding antivortex in the idler of the OPO. The experimental results are in good agreement with a theoretical model of a vortex in the polariton OPO.

17.
Phys Rev Lett ; 101(6): 067404, 2008 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-18764503

RESUMO

The fundamental mechanisms which control the phase coherence of the polariton Bose-Einstein condensate (BEC) are determined. It is shown that the combination of number fluctuations and interactions leads to decoherence with a characteristic Gaussian decay of the first-order correlation function. This line shape, and the long decay times ( approximately 150 ps) of both first- and second-order correlation functions, are explained quantitatively by a quantum-optical model which takes into account interactions, fluctuations, and gain and loss in the system. Interaction limited coherence times of this type have been predicted for atomic BECs, but are yet to be observed experimentally.

18.
Phys Rev Lett ; 99(19): 195002, 2007 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-18233082

RESUMO

The rate of laser ablation at irradiances of approximately 2 x 10{14} W cm{-2} of solid iron has been measured using the transmission of a neonlike zinc x-ray laser at 21.2 nm through thin iron targets. Ablated iron becomes transparent to the x-ray laser flux, enabling the thickness of unablated material and hence the rate of ablation to be measured from time resolved x-ray laser transmission.

19.
Opt Express ; 15(22): 14299-305, 2007 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-19550706

RESUMO

We model the optical properties of L3 photonic crystal nano-cavities as a function of the photonic crystal membrane refractive index n using a guided mode expansion method. Band structure calculations revealed that a TE-like full band-gap exists for materials of refractive index as low as 1.6. The Q-factor of such cavities showed a super-linear increase with refractive index. By adjusting the relative position of the cavity side holes, the Q-factor was optimised as a function of the photonic crystal membrane refractive index n over the range 1.6 to 3.4. Q-factors in the range 3000-8000 were predicted from absorption free materials in the visible range with refractive index between 2.45 and 2.8.

20.
Opt Express ; 15(25): 17221-30, 2007 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-19551015

RESUMO

We study the linear polarization of the emission from single quantum dots embedded in an "L3" defect nanocavity in a two-dimensional photonic crystal. By using narrow linewidth optical excitation in resonance with higher-order modes, we are able to achieve strong quantum dot emission intensity whilst reducing the background from quantum dots in the surrounding lattice. We find that all the dots observed emit very strongly linearly polarized light of the same orientation as the closest mode, despite the fact that these quantum dots may be spectrally detuned by several times the mode linewidth. We discuss the coupling mechanisms which may explain this behavior.

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