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1.
Opt Express ; 28(3): 4320-4332, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32122086

RESUMEN

Super-resolved angular displacement estimation is of crucial significance to the field of quantum information processing. Here we report an estimation protocol based on a Sagnac interferometer fed by a coherent state carrying orbital angular momentum. In a lossless scenario, through the use of parity measurement, our protocol can achieve a 4ℓ-fold super-resolved output with quantum number ℓ; meanwhile, a shot-noise-limited sensitivity saturating the quantum Cramér-Rao bound is reachable. We also consider the effects of several realistic factors, including nonideal state preparation, photon loss, and inefficient measurement. Finally, with mean photon number N¯=2.297 and ℓ = 1 taken, we experimentally demonstrate a super-resolved effect of angular displacement with a factor of 7.88.

2.
Sensors (Basel) ; 20(9)2020 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-32370109

RESUMEN

The piezoelectric actuator is indispensable for driving the micro-manipulator. In this paper, a simplified interval type-2 (IT2) fuzzy system is proposed for hysteresis modelling and feedforward control of a piezoelectric actuator. The partial derivative of the output of IT2 fuzzy system with respect to the modelling parameters can be analytically computed with the antecedent part of IT2 fuzzy rule specifically designed. In the experiments, gradient based optimization was used to identify the IT2 fuzzy hysteresis model. Results showed that the maximum error of model identification is 0.42% with only 3 developed IT2 fuzzy rules. Moreover, the model validation was conducted to demonstrate the generalization performance of the identified model. Based on the analytic inverse of the developed model, feedforward control experiment for tracking sinusoidal trajectory of 20 Hz was carried out. As a result, the hysteresis effect of the piezoelectric actuator was reduced with the maximum tracking error being 4.6%. Experimental results indicated an improved performance of the proposed IT2 fuzzy system for hysteresis modelling and feedforward control of the piezoelectric actuator.

3.
Opt Express ; 27(4): 5512-5522, 2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30876153

RESUMEN

We demonstrate a tried-and-true binary strategy for angular displacement estimation, of which the measuring system is a modified Mach-Zehnder interferometer fed by a coherent state carrying orbital angular momentum, and two Dove prisms are embedded in two arms. Unlike previous protocols, in this paper, we use fidelity instead of standard deviation to evaluate the detection strategies. Two binary strategy candidates, parity detection and Z detection, are considered and compared. In addition, we study the effects of several realistic scenarios on the estimation protocol, including transmission loss, detection efficiency, dark counts, and those which are a combination thereof. Finally, we exhibit a proof-of-principle experiment, the results suggest a resolution enhancement effect with a factor of 3.72.

4.
Opt Express ; 26(25): 33080-33090, 2018 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-30645465

RESUMEN

In this paper, we propose a protocol for the estimation of angular displacement based upon orbital angular momentum and an SU(1,1)-SU(2) hybrid interferometer. This interferometer consists of an optical parametric amplifier, a beam splitter, and reflection mirrors; the balanced homodyne detection is used as the detection strategy. The results indicate that super-resolution and super-sensitivity can be achieved with an ideal scenario. Additionally, we study the effect of photon loss on resolution and sensitivity, and the robustness of our protocol is also discussed. Finally, the advantage of our protocol compared with an SU(1,1) protocol is demonstrated, and the merits of orbital angular momentum-enhanced protocol are summarized.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(2): 545-548, 2019 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30998168

RESUMEN

OBJECTIVE: To investigate the gene mutation types and distribution features of α- and ß-thalassemia in reproductive population of Xing bin district of Guangxi Lai bin city so as to provide the scientific basis for formulating the preventive and control measures. METHODS: The high risk population with thalassemia in 6 498 people of child-bearing age admited in department of antenatal care of our hospital from January 2017 to December 2017 were screened by blood cell test and hemoglobin electrophoresis. The gene mutation types and mutation frequency in αandßthalassemia positive cases were diagnosed and analyzied by Gap-PCR and PCR-RDB. RESULTS: The inital screening showed that there were 1 432 cases of thalassemia positive accounting for 22.04%; the gene diagnoses showed that there were 920 cases of thalassemia gene positive accounting for 14.16%. Among 920 cases, 593 cases were α-thalassemia accounting for 64.45% (593/920); the gene mutation types were 19 kinds. The α-deletion type gene was mainly --SEA (47.22%), the α-mutatin type gene was mainly -αcsα(13.66%); 260 cases were the ß-thalassemia accounting for 28.26%, (260/920), the gene mutation types were 9 kinds, out of which the ß41-42 ßN was main (50.38%), followed by ß17/ßN (38.08%),there were 2 kinds of gene mutation types accounted for 88.46%; the αß-thalassemia numbered 67 cases (7.28%), the mutation types were mainly --SEA/ß41-42 (17.91%) and -α3.7/ß41-42 (17.91%). CONCLUSION: The α-and ß-thalassemia mostly observed in the childbearing population of Laibin city Xinbin district possess the gene comblexity and diversity as well as the significant genetic heterogeneily.The results of this study provide the reference basis for the prevention of thalassemia and eugenic works.


Asunto(s)
Mutación , Niño , China , Femenino , Genotipo , Humanos , Embarazo , Talasemia alfa , Talasemia beta
6.
Eur J Haematol ; 81(6): 461-6, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18774951

RESUMEN

We retrospectively analyzed 23 cases with early-onset idiopathic pneumonia syndrome (IPS) of 192 patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) from April 1997 to October 2007. Risk factors for IPS development were evaluated using Cox proportional hazards model, including age, gender, underlying disease, disease status at transplant, transplant type, conditioning regimens, donor type, acute graft-vs.-host disease (GVHD), severity of acute GVHD (aGVHD), human leukocyte antigen (HLA) disparity, and organ involvement of aGVHD. Factors that were significant at the 0.1 level on univariate analysis were evaluated by multivariate analysis. Twenty-three of 192 patients developed IPS (12.0%). Median time to IPS onset after allogeneic HSCT was 76 d (range 32-120 d); median time to death after the diagnosis of IPS was 9 d (range 3-92 d); 20 patients with IPS died because of the rapid progression of respiratory failure (87.0%). Nineteen patients with IPS developed aGVHD (82.6%), with grade III-IV aGVHD in 11 patients (47.8%) and aGVHD of gut in 16 patients (69.6%). The following six factors were associated with an increased risk of IPS by univariate analysis: not in remission, unrelated donor, HLA disparity, occurrence of aGVHD, grade III-IV aGVHD and aGVHD of gut. These risk factors were entered into a multivariate analysis model. Only unrelated donor, grade III-IV aGVHD and aGVHD of gut are identified as being significantly associated with the occurrence of IPS, and among them, aGVHD of gut was associated with the largest risk of IPS, suggesting that the lung may be a target organ of aGVHD.


Asunto(s)
Enfermedad Injerto contra Huésped/epidemiología , Trasplante de Células Madre Hematopoyéticas , Modelos Biológicos , Neumonía/epidemiología , Insuficiencia Respiratoria/epidemiología , Acondicionamiento Pretrasplante , Enfermedad Aguda , Adolescente , Adulto , Niño , Preescolar , Femenino , Enfermedad Injerto contra Huésped/complicaciones , Antígenos HLA , Neoplasias Hematológicas/epidemiología , Neoplasias Hematológicas/terapia , Humanos , Incidencia , Enfermedades Intestinales/epidemiología , Enfermedades Intestinales/etiología , Masculino , Persona de Mediana Edad , Neumonía/etiología , Insuficiencia Respiratoria/etiología , Estudios Retrospectivos , Factores de Riesgo , Síndrome , Trasplante Homólogo
7.
Medicine (Baltimore) ; 95(11): e3124, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26986163

RESUMEN

Although cosmetic facial soft tissue fillers are generally safe and effective, improper injections can lead to devastating and irreversible consequences. We represent the first known case of posterior ciliary artery occlusion caused by hyaluronic acid. A 41-year-old female presented with right visual loss 7 hours after receiving cosmetic hyaluronic acid injections into her forehead. Examination revealed no light perception in the right eye and multiple dark ischemic area of injection over the forehead and nose. The right fundus revealed a pink retina with optic nerve edema. Fluorescein angiogram showed several filling defects in the choroidal circulation and late hyperfluorescence in the choroid. A right posterior ciliary artery occlusion and embolic occlusion of facial artery braches was diagnosed. With hyaluronidase injection, hyperbaric oxygen therapy, oral aspirin, oral acetazolamide and dexamethasone venotransfuse treatment, the patient's forehead and nasal skin improved and vision recovered to hand movements. With proper technique, vascular occlusion is rare following facial filler injection. Vision consequences can be severe if filler emboli enter the ocular circulation. Physicians should be aware of this potential side effect, recognize its presentation, and be knowledgeable of effective management.


Asunto(s)
Arterias Ciliares , Técnicas Cosméticas/efectos adversos , Rellenos Dérmicos/efectos adversos , Embolia/inducido químicamente , Ácido Hialurónico/efectos adversos , Adulto , Ceguera/inducido químicamente , Femenino , Frente , Humanos , Inyecciones Subcutáneas
8.
J Zhejiang Univ Sci B ; 10(10): 784-90, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19817004

RESUMEN

Dissipation mechanisms of excess photon energy under high-temperature stress were studied in a subtropical forest tree seedling, Ficus concinna. Net CO(2) assimilation rate decreased to 16% of the control after 20 d high-temperature stress, and thus the absorption of photon energy exceeded the energy required for CO(2) assimilation. The efficiency of excitation energy capture by open photosystem II (PSII) reaction centres (F(v)'/F(m)') at moderate irradiance, photochemical quenching (q(P)), and the quantum yield of PSII electron transport (Phi(PSII)) were significantly lower after high-temperature stress. Nevertheless, non-photochemical quenching (q(NP)) and energy-dependent quenching (q(E)) were significantly higher under such conditions. The post-irradiation transient of chlorophyll (Chl) fluorescence significantly increased after the turnoff of the actinic light (AL), and this increase was considerably higher in the 39 degrees C-grown seedlings than in the 30 degrees C-grown ones. The increased post-irradiation fluorescence points to enhanced cyclic electron transport around PSI under high growth temperature conditions, thus helping to dissipate excess photon energy non-radiatively.


Asunto(s)
Ficus/metabolismo , Complejo de Proteína del Fotosistema I/metabolismo , Aclimatación/fisiología , Clorofila/metabolismo , Transporte de Electrón , Fluorescencia , Calor , Fotosíntesis , Clima Tropical
9.
J Mater Sci Mater Med ; 20(3): 751-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18987946

RESUMEN

5-fluorouracil-SiO(2)-poly(L-lactide) (5-Fu-SiO(2)-PLLA) microcapsules were prepared in a novel process of solution-enhanced dispersion by supercritical CO(2) (SEDS). The SiO(2) nanoparticles were loaded with 5-Fu by adsorption at the first place, then the 5-Fu-SiO(2) nanoparticles were coated with PLLA by a modified SEDS process. The resulted microcapsules were characterized by scanning electron microscope (SEM), laser diffraction particle size analyzer, Fourier transform infrared spectrometer (FTIR) and thermogravimeter-differential scanning calorimeter (TG-DSC). The drug load, encapsulation efficiency and drug release profiles were also determined. The resulted microcapsules exhibited a rather spherical shape, smooth surface, and a narrow particle size distribution with a mean particle size of 536 nm. The drug load and encapsulation efficiency of the samples were 0.18% and 80.53%, respectively, 25.05% of 5-Fu was released in the first half hour, then drug released in a sustained process, which was much slower than that of without coated by PLLA. The results indicated that the modified SEDS process could be used to produce drug-polymer microcapsules with a core-shell structure, high encapsulation efficiency and sustained drug release effect.


Asunto(s)
Cápsulas/síntesis química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Cápsulas/química , Dióxido de Carbono , Preparaciones de Acción Retardada , Composición de Medicamentos/instrumentación , Composición de Medicamentos/métodos , Fluorouracilo/administración & dosificación , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Poliésteres/química , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Termodinámica
10.
J Colloid Interface Sci ; 330(2): 317-22, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19036387

RESUMEN

The Fe(3)O(4)-poly(L-lactide) (Fe(3)O(4)-PLLA) magnetic microparticles were successfully prepared in a process of solution-enhanced dispersion by supercritical CO(2) (SEDS), and their morphology, particle size, magnetic mass content, surface atom distribution and magnetic properties were characterized. Indomethacin (Indo) was used as a drug model to produce drug-polymer magnetic composite microparticles. The resulting Fe(3)O(4)-PLLA microparticles with mean size of 803 nm had good magnetic property and a saturation magnetization of 24.99 emu/g. The X-ray photoelectron spectroscopy (XPS) test indicated that most of the Fe(3)O(4) were encapsulated by PLLA, which indicated that the Fe(3)O(4)-PLLA magnetic microparticles had a core-shell structure. After further loading with drug, the Indo-Fe(3)O(4)-PLLA microparticles had a bigger mean size of 901 nm, and the Fourier transform infrared spectrometer (FTIR) analysis demonstrated that the SEDS process was a typical physical coating process to produce drug-polymer magnetic composite microparticles, which is favorable for drugs since there is no change in chemistry. The in vitro cytotoxicity test showed that the Fe(3)O(4)-PLLA magnetic microparticles had no cytotoxicity and were biocompatible, which means there is potential for biomedical application.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Compuestos Férricos/química , Magnetismo , Poliésteres/química , Animales , Materiales Biocompatibles , Dióxido de Carbono , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Composición de Medicamentos , Humanos , Indometacina/administración & dosificación , Tamaño de la Partícula
11.
Acta Biomater ; 5(8): 2913-9, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19463980

RESUMEN

Puerarin nanoparticles were firstly prepared in the process of solution-enhanced dispersion by supercritical CO(2) (SEDS) and then successfully microencapsulated by poly(l-lactide) (PLLA) in a modified SEDS process. By adding an organic non-solvent, an initial puerarin solution with a higher degree of saturation and lower concentration was obtained and applied in the SEDS process. The resulting puerarin nanoparticles were then suspended in PLLA solution and microencapsulated by PLLA in a modified SEDS process, where an 'injector' was employed in the particle suspension delivery system. The puerarin nanoparticles exhibited a good spherical shape, a smooth surface and a narrow particle size distribution with a mean particle size of 188 nm. After microencapsulation the puerarin-PLLA microparticles had a mean size of 675 nm, a drug load of 23.6% and an encapsulation efficiency of 39.4%; after a burst release at the first stage, the drug was released in a sustained process. Compared with the parallel study of a co-precipitation process, this microencapsulation process is a much more promising technique to prepare a drug-polymer carrier for a drug delivery system, especially for protein drugs.


Asunto(s)
Materiales Biocompatibles/química , Cromatografía con Fluido Supercrítico/métodos , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Isoflavonas/química , Nanopartículas/química , Nanopartículas/ultraestructura , Poliésteres/química , Absorción , Cápsulas , Cristalización/métodos , Difusión , Isoflavonas/administración & dosificación , Ensayo de Materiales , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Vasodilatadores/administración & dosificación , Vasodilatadores/química
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