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1.
Food Chem ; 370: 131340, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34662791

RESUMEN

The preliminary study examined the effectiveness of various vegetables for the stabilisation of omega-3 oil powders against oxidative deterioration. Purees made from different vegetables (mushroom, brussels sprouts, broccoli, cauliflower, snow peas, tomato, and garlic) were employed for preparation of vegetable-tuna oil emulsions, which were subsequently freeze-dried into powders. Oxipres® data showed that vegetable-tuna oil powders had longer induction periods than neat tuna oil. During accelerated oxidation storage (40 °C/4weeks), eicosapentaenoic and docosahexaenoic acids in the vegetable-tuna oil powders were protected against oxidation, and there were lower levels of headspace secondary and tertiary oxidation products. Whole vegetable purees were suitable protective matrices for omega-3 oils. Of the various vegetable purees examined for protective effects against omega-3 oxidation, mushroom, brussels sprouts, broccoli, and cauliflower were superior to snow peas, garlic and tomato. The antioxidant properties of phytonutrients inherent in various vegetables are likely contributors to protection of omega-3 oil powders against oxidation.


Asunto(s)
Ácidos Grasos Omega-3 , Verduras , Oxidación-Reducción , Estrés Oxidativo , Polvos
2.
Clin. transl. oncol. (Print) ; 23(4): 773-782, abr. 2021. graf
Artículo en Inglés | IBECS | ID: ibc-220913

RESUMEN

Purpose Current gastric cancer staging systems overlook the anatomic extent of metastatic lymph nodes (AEMLNs). This study aimed to analyze the prognostic impact of AEMLNs on gastric cancer (GC). Methods GC patients with metastatic lymph nodes (MLNs) undergoing curative surgery were retrospectively reviewed and assigned to perigastric (MLNs in station 1–6, PG) and extraperigastric group (7-12, with or without MLNs in PG area, EPG). Overall survival (OS), disease-free survival (DFS) and recurrence patterns were compared before and after 1:1 propensity score matching (PSM). Results 662 patients were enrolled, 341 (51.5%) and 321 (48.5%) of whom were in the PG and EPG, respectively. After PSM (n = 195), EPG showed poorer 5-year OS (43.4% vs 54.5%, p = 0.014) and DFS (65.0% vs 73.4%, p = 0.068) than PG. EPG had higher incidence of peritoneal recurrence (PR) than PG (19.4% vs 7.4%, p = 0.002). Multivariate analysis identified AEMLNs as prognostic factor for OS [HR = 1.409, 95% confidence interval (CI) 1.062–1.868), DFS (HR = 1.600, 95% CI 1.059–2.416) and PR (HR = 3.708, 95% CI 1.685–8.160). Conclusions The anatomic extent of metastatic lymph nodes has an independent prognostic role for GC. Including this element may improve the accuracy of current staging systems (AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Ganglios Linfáticos/patología , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Estudios Retrospectivos , Análisis de Varianza , Supervivencia sin Enfermedad , Pronóstico , Recurrencia Local de Neoplasia , Neoplasias Gástricas/cirugía
3.
Clin Transl Oncol ; 23(4): 773-782, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32772226

RESUMEN

PURPOSE: Current gastric cancer staging systems overlook the anatomic extent of metastatic lymph nodes (AEMLNs). This study aimed to analyze the prognostic impact of AEMLNs on gastric cancer (GC). METHODS: GC patients with metastatic lymph nodes (MLNs) undergoing curative surgery were retrospectively reviewed and assigned to perigastric (MLNs in station 1-6, PG) and extraperigastric group (7-12, with or without MLNs in PG area, EPG). Overall survival (OS), disease-free survival (DFS) and recurrence patterns were compared before and after 1:1 propensity score matching (PSM). RESULTS: 662 patients were enrolled, 341 (51.5%) and 321 (48.5%) of whom were in the PG and EPG, respectively. After PSM (n = 195), EPG showed poorer 5-year OS (43.4% vs 54.5%, p = 0.014) and DFS (65.0% vs 73.4%, p = 0.068) than PG. EPG had higher incidence of peritoneal recurrence (PR) than PG (19.4% vs 7.4%, p = 0.002). Multivariate analysis identified AEMLNs as prognostic factor for OS [HR = 1.409, 95% confidence interval (CI) 1.062-1.868), DFS (HR = 1.600, 95% CI 1.059-2.416) and PR (HR = 3.708, 95% CI 1.685-8.160). CONCLUSIONS: The anatomic extent of metastatic lymph nodes has an independent prognostic role for GC. Including this element may improve the accuracy of current staging systems.


Asunto(s)
Ganglios Linfáticos/patología , Metástasis Linfática/patología , Recurrencia Local de Neoplasia/patología , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Análisis de Varianza , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Neoplasias Peritoneales/secundario , Pronóstico , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Neoplasias Gástricas/cirugía
4.
Opt Lett ; 45(24): 6736-6739, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33325884

RESUMEN

We experimentally demonstrate the direct strong coupling between the S0→S1 absorption transition of rhodamine 6G (R6G) dye molecules and the surface plasmon polaritons of a hyperbolic metamaterial (HMM) substrate. The surface plasmon mode was excited by a guided mode of the R6G-doped polymer thin film on the HMM. The coupling strengths of the interactions between the surface plasmon and two molecular exciton modes are greater than the average linewidths of the individual modes indicating a strong coupling regime. This is the first, to the best of our knowledge, experimental demonstration of the direct strong coupling between the resonance mode supported by the HMM and the dye molecules on the HMM surface, not embedded in the HMM structure. The study may provide the foundation for the development of novel planar photonic or electronic devices.

5.
Zhonghua Yi Xue Za Zhi ; 97(24): 1867-1870, 2017 Jun 27.
Artículo en Chino | MEDLINE | ID: mdl-28648010

RESUMEN

Objective: To study the surgical treatment of chronic type B dissection with aortic arch involvement using Sun's procedure. Methods: Between February 2009 and December 2015, 29 patients [20 males, 9 females, with a mean age of (41±12) years, range 24-64 years] with type B dissection with aortic arch involvement underwent Sun's procedure. Sixteen patient had a history of hypertension. Marfan syndrome was observed in 9 cases, coronary artery disease in 3 cases, mitral regurgitation in 3 patients, cerebrovascular disease in one patient. Twenty-two patients suffered proximal aortic arch disease, 4 cases experienced history of aortic root procedure and 2 subjects had history of pregnancy. Four patients had aortic arch malformation. Results: One case suffered from massive cerebral infarction after surgery and died in another hospital. Concomitant procedures included mitral valve replacement in 3 cases, coronary artery bypass grafting in 3 patients, reconstruction of the right aberrant subclavian artery in one patient. Ventilator support exceeding 24 hours obseved in 2 patients. One of them recieved continuous renal replacement therapy and recovered before discharge. Spinal cord injury was obseved in one case, brain infarction in one patient and pericardial drainage in one case. Two patients required tracheotomy. During 12-94 (43±23) months' follow-up, thoracoabdominal aortic replacment was performed in 4 patients, thoracic endovascular aortic repair (TEVAR) in 2 subjects and repair of perivalvular leakage in one patient. Conclusions: Sun's procedure obtained satisfactory results in patients with chronic type B dissection with aortic arch involvement. Concomitant repair of proximal aortic arch lesions and distal type B dissection can be adopted using Sun's procedure.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Disección Aórtica/cirugía , Adulto , Anciano , Aorta , Aorta Torácica/patología , Implantación de Prótesis Vascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Stents , Arteria Subclavia , Resultado del Tratamiento , Adulto Joven
7.
Zhonghua Yi Xue Za Zhi ; 96(13): 1007-10, 2016 Apr 05.
Artículo en Chino | MEDLINE | ID: mdl-27055791

RESUMEN

OBJECTIVE: To evaluate the application value of evoked potentials (EP) monitoring in patients undergoing aorta-iliac bypass for total thoracoabdominal aorta aneurysm repair (tTAAAR). METHODS: A prospective study, with a total of 31 patients undergoing tTAAAR and intraoperative EP monitoring from June 2014 to April 2015 was carried out. The results of intraoperative evoked potentials, clinical outcomes and follow-up data of patients were collected for further evaluation. RESULTS: The EP wave disappeared [motor evoked potentials for (55.6±18.1) min, somatosensory evoked potentials for (50.3±18.7) min] after proximal descending aorta being clamped, and gradually recovered after the segment arteries of spine cord were reconstructed. The EP wave was restored to normal level at the end of operation in all the cases. The somatosensory evoked potentials remained unchanged in 2 cases (false negative). One case died after operation. No spinal cord injury occurred. The median follow-up after operation was 10 months (5-14 months). There was no delayed neurological deficit. CONCLUSION: EP provided an on-line monitoring of the condition of spinal cord function, which become an intraoperative protocol to avoid the irreversible injury of spinal cord.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Potenciales Evocados Motores , Potenciales Evocados Somatosensoriales , Monitoreo Intraoperatorio , Procedimientos Quirúrgicos Vasculares/métodos , Aneurisma de la Aorta Torácica/diagnóstico , Aneurisma de la Aorta Torácica/fisiopatología , Humanos , Estudios Prospectivos , Procedimientos de Cirugía Plástica
8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(5 Pt 2): 056104, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23214840

RESUMEN

As in electrochemical cyclic voltammetry, time-periodic reverse voltage bias across a bipolar membrane is shown to exhibit hysteresis due to transient effects. This is due to the incomplete depletion of mobile ions, at the junction between the membranes, within two adjoining polarized layers; the layer thickness depends on the applied voltage and the surface charge densities. Experiments show that the hysteresis consists of an Ohmic linear rise in the total current with respect to the voltage, followed by a decay of the current. A limiting current is established for a long period when all the mobile ions are depleted from the polarized layer. If the resulting high field within the two polarized layers is sufficiently large, water dissociation occurs to produce proton and hydroxyl traveling wave fronts which contribute to another large jump in the current. We use numerical simulation and asymptotic analysis to interpret the experimental results and to estimate the amplitude of the transient hysteresis and the water-dissociation current.


Asunto(s)
Membranas Artificiales , Modelos Químicos , Agua/química , Simulación por Computador , Difusión , Campos Electromagnéticos
9.
Ultrason Sonochem ; 18(5): 963-73, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21489848

RESUMEN

The effects of application of ultrasonic waves to recombined milk emulsions (3.5% fat, 7% total solids) and raw milk on fat destabilization and creaming were examined. Coarse and fine recombined emulsions (D[4,3]=9.3 µm and 2.7 µm, respectively) and raw milk (D[4,3]=4.9 µm) were subjected to ultrasound for 5 min at 35°C and 400 kHz or 1.6 MHz (using a single transducer) or 400 kHz (where the emulsion was sandwiched between two transducers). Creaming, as calculated from Turbiscan measurements, was more evident in the coarse recombined emulsion and raw milk compared to that of the recombined fine emulsion. Micrographs confirmed that there was flocculation and coalescence in creamed layer of emulsion. Coalescence was confirmed by particle size measurement. These results imply that ultrasound has potential to pre-dispose fat particles in milk emulsions to creaming in standing wave systems and in systems with inhomogeneous sound distributions.


Asunto(s)
Productos Lácteos/análisis , Grasas/química , Grasas/efectos de la radiación , Leche/química , Leche/efectos de la radiación , Nefelometría y Turbidimetría/métodos , Sonicación/métodos , Animales , Emulsiones/química , Emulsiones/efectos de la radiación , Manipulación de Alimentos , Dosis de Radiación , Viscosidad
10.
Arterioscler Thromb Vasc Biol ; 19(6): 1559-65, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10364090

RESUMEN

Vigorous exercise transiently increases the risk of primary cardiac arrest. Strenuous, acute exercise can also increase the release of plasma epinephrine. Previous investigations have indicated that epinephrine can potentiate platelet activation by activating platelet alpha2-adrenoceptors. This study investigated how strenuous, acute exercise affects alpha2-adrenergic agonist-potentiated platelet activation by closely examining 15 sedentary men who exercised strenuously on a bicycle ergometer. Before and immediately after exercise, platelet adhesiveness on fibrinogen-coated surfaces, [Ca2+]i in platelets, the number and affinity of alpha2-adrenergic sites on the platelet surface, and plasma catecholamine levels were determined. The results of this study can be summarized as follows: (1) The affinity of alpha2-adrenergic receptors on platelets decreases while the maximal binding number significantly increases after strenuous exercise, thereby correlating with the rise in plasma catecholamine levels. (2) Basal, clonidine-treated, ADP-treated, and clonidine plus ADP-treated adhesiveness and [Ca2+]i in platelets increased after strenuous exercise. (3) Strenuous exercise is associated with higher percentages of ADP- and clonidine plus ADP-enhanced platelet adhesiveness and [Ca2+]i than at rest. (4) The synergistic effects of clonidine on ADP-enhanced platelet adhesiveness and [Ca2+]i after strenuous exercise are much greater than those at rest. Therefore, we conclude that strenuous, acute exercise enhances platelet activation, possibly by altering the performance of platelet alpha2-adrenergic receptors, facilitating the ability of ADP-activated fibrinogen receptors, and enhancing fibrinogen binding to platelet fibrinogen receptors.


Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2 , Agonistas alfa-Adrenérgicos/farmacología , Ejercicio Físico , Activación Plaquetaria/efectos de los fármacos , Adenosina Difosfato/farmacología , Adulto , Calcio/metabolismo , Catecolaminas/sangre , Clonidina/metabolismo , Clonidina/farmacología , Humanos , Masculino
11.
Neurosci Lett ; 218(1): 67-71, 1996 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-8939482

RESUMEN

The present study examined the effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 5,7-dihydroxytryptamine (5,7-DHT) on striatal levels of dopamine (DA), 5-hydroxytryptamine (5-HT), and their metabolites homovanillic acid (HVA) and 5-hydroxyindole-3-acetic acid (5-HIAA), respectively, as well as their influence on locomotor activity in conscious C57BL/6 mice. High doses (s.c., 35-45 mg/kg per day for 10 days) of MPTP resulted in a significant (P < 0.05) increase in locomotor activity and a marked decrease of striatal DA levels. Concomitantly, the ratios of HVA to DA and 5-HIAA to 5-HT increased significantly, the latter reflecting increased 5-HIAA levels. In contrast, i.c.v. administration of the serotonergic neurotoxin 5,7-DHT, either alone or following high doses (40 mg/kg per day for 10 days) of MPTP, decreased locomotor activity. Furthermore, striatal levels of 5-HT and 5-HIAA as well as the 5-HIAA/5-HT ratio decreased significantly. Thus, the increased locomotor activity induced by chronic high doses of MPTP might be due to increased striatal 5-HT levels which appear to compensate for the loss of DA. Furthermore, the locomotor hypoactivity induced by 5,7-DHT may be secondary to the striatal 5-HT deficiency.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , 5,7-Dihidroxitriptamina/farmacología , Aminas Biogénicas/metabolismo , Cuerpo Estriado/efectos de los fármacos , Locomoción/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Ratones , Ratones Endogámicos C57BL
12.
J Neurol Sci ; 133(1-2): 73-8, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8583235

RESUMEN

Twenty-two patients with Parkinson's disease (PD) were studied by clinical evaluation, assessments of dementia and depression, as well as electrophysiologic examinations for blink reflex (BR), cortical somatosensory evoked potentials (CSEP), brain stem, and long-latency auditory evoked potentials (BAEP, and LAEP), and cerebrospinal fluid (CSF) assays for monoamine metabolites. Results show that PD patients have a significant decrease of Mini-Mental State Examination (MMSE) scores (p < 0.05) and an increase of Hamilton Depression Scale (HDS) scores (p < 0.01), as well as a longer latencies of R2 in BR, N19 and P22 in CSEP, W4 and W5 in BAEP and P300 in LAEP (p < 0.01), and lower CSF levels of HVA and MHPG (p < 0.05). The findings suggest a correlation between dementia/depression and mesocorticolimbic and mesostriatocortic dysfunction with dopaminergic and noradrenergic deficiencies in PD patients. Furthermore, parkinsonian dementia parallels the length of duration of the disease, but not the severity of motor disability. Parkinsonian depression parallels both the length of duration of the disease and the severity of motor disability.


Asunto(s)
Monoaminas Biogénicas/líquido cefalorraquídeo , Demencia/etiología , Depresión/etiología , Potenciales Evocados Auditivos/fisiología , Potenciales Evocados Somatosensoriales/fisiología , Enfermedad de Parkinson/fisiopatología , Anciano , Parpadeo/fisiología , Progresión de la Enfermedad , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Femenino , Humanos , Masculino , Enfermedad de Parkinson/líquido cefalorraquídeo , Enfermedad de Parkinson/psicología , Pruebas Psicológicas
13.
Chem Senses ; 19(5): 371-80, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7881971

RESUMEN

Conjugated bile acids such as taurocholic acid (TChA) are potent olfactory stimuli for Atlantic salmon (Salmo salar). A plasma membrane rich fraction was derived from salmon olfactory rosettes and used to investigate TChA signal transduction and receptor binding. In the presence of GTP gamma S, TChA caused dose-dependent stimulation of phosphatidylinositol 4,5-bisphosphate (PIP2) breakdown, half maximal at less than 10(-7) M TChA. Stimulation of PIP2 breakdown by TChA required GTP gamma S, was blocked by GDP beta S, and was mimicked by A1F4-, consistent with a G protein requirement. A1F4- and Ca2+ stimulated breakdown of PIP2, but not phosphatidylcholine, arguing against a non-specific lipase activation. Stimulation of PIP2 breakdown by TChA was maximal at low Ca2+ concentration, < or = 10 nM. Conventional binding analysis with 3H-TChA was inconclusive due to a high degree of non-specific binding and to lack of tissue specificity expected for an olfactory receptor. Analysis of odorant amino acid binding indicated possible interaction of TChA with a putative acidic amino acid receptor but no interaction of TChA with a putative neutral amino acid receptor. We conclude that olfactory discrimination between amino acids and bile acids occurs in part at the receptor level while both classes of odors appear to use the same signal transduction mechanism, G protein mediated activation of phosphoinositide specific phospholipase C (PLC).


Asunto(s)
Salmón/metabolismo , Olfato/fisiología , Ácido Taurocólico/metabolismo , Aminoácidos/metabolismo , Animales , Ácidos y Sales Biliares/metabolismo , Calcio/farmacología , Proteínas de Unión al GTP/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Técnicas In Vitro , Fosfatidilinositol 4,5-Difosfato , Fosfatidilinositol Diacilglicerol-Liasa , Fosfatos de Fosfatidilinositol/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Receptores de Aminoácidos/metabolismo , Receptores Odorantes/metabolismo , Transducción de Señal/fisiología
14.
Dev Genet ; 13(1): 26-33, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1395138

RESUMEN

To investigate the role of cilia in mating interactions of Tetrahymena thermophila, ciliary membrane-rich fractions were isolated from two wild-type strains, a non-discharge mucocyst mutant which possesses mating behavior similar to wild-type, and a mating mutant which is able to costimulate cells of complementary mating type but cannot enter into pair formation. In each case, proteins from the ciliary membrane-rich fractions of starved, mating-competent ("initiated") cells were compared with those from non-starved, mating-incompetent ("non-initiated") cells, by gel electrophoresis and lectin blotting. In stained gels, a 43 kDa polypeptide was reduced or absent in initiated cells but present in non-initiated cells, in all strains. In silver-stained gels, a 25 kDa polypeptide was present in all strains, both initiated and non-initiated. In blots probed with Con A-peroxidase, a 25 kDa glycoprotein was present in ciliary membrane fractions from non-initiated cells and absent in membranes of initiated cells of the two wild-type strains and the mucocyst mutant, but is present in initiated and non-initiated cells of the mating mutant (several hypotheses are presented to explain these findings). In addition, ciliary proteins of the mating mutant included at least two unique Con A-binding polypeptides. Our results support the idea that development of mating competence during starvation involves an extensive remodeling of ciliary membranes, and identify a 25 kDa glycoconjugate as having a potential role in control of pair formation during mating.


Asunto(s)
Cilios/fisiología , Glicoconjugados/fisiología , Péptidos/fisiología , Proteínas Protozoarias , Tetrahymena thermophila/fisiología , Animales , Cilios/ultraestructura , Electroforesis en Gel de Poliacrilamida , Privación de Alimentos , Glicoconjugados/genética , Lectinas , Proteínas de la Membrana/metabolismo , Microscopía Electrónica , Mutación , Péptidos/genética , Proteínas Protozoarias/genética , Reproducción/fisiología , Tetrahymena thermophila/genética , Tetrahymena thermophila/ultraestructura
15.
Appl Opt ; 31(26): 5675-80, 1992 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-20733752

RESUMEN

A real-time GaAs and liquid-crystal television- (LCTV-) based optical correlator is demonstrated. The speed of this correlator (video rate) is limited by the LCTV's; with faster spatial light modulators, the potential speed of a GaAs-based correlator may be 1000 frames/s or higher. Comparisons are made between VanderLugt and joint transform configurations and between degenerate and nondegenerate four-wave mixings. The edge-enhancement effect and the Bragg diffraction effect are also discussed.

16.
Opt Lett ; 13(1): 50-2, 1988 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19741977

RESUMEN

We report theoretical and experimental investigations on the cross-polarization coupling of two contradirectional laser beams in a photorefractive GaAs crystal. There is good agreement between these results.

17.
Appl Opt ; 27(6): 1006-7, 1988 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20531509
18.
Appl Opt ; 27(9): 1760-3, 1988 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-20531648

RESUMEN

The index grating lifetime in liquid encapsulated Czochralski-grown undoped semi-insulating GaAs was measured using a beam coupling technique. The largest lifetime measured was ~8 s under a read beam intensity of 0.7 mW/cm(2) with the grating periodicity being 0.63 microm. The measured value decreases to milliseconds as the read beam intensity and the grating periodicity increase to ~10 mW/cm(2) and 4 microm, respectively. This range of grating lifetime in this material is adequate for its use in real-time spatial light modulators, reconfigurable beam steering devices, and dynamic memory elements for optical computing. In addition, the results suggest that, the lifetime is sensitive to residual imperfections in the crystal.

19.
Appl Opt ; 27(13): 2756-61, 1988 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20531833

RESUMEN

An updatable optical correlator which uses a photorefractive compound semiconductor to generate real-time matched filters is proposed. Using compound semiconductors offers high speed with low optical input intensities. Here we discuss issues affecting the performance of this correlator. This includes an analysis of the Bragg diffraction and a discussion of the speed and power considerations of these materials. Experimental results obtained using photorefractive GaAs are also presented.

20.
Appl Opt ; 27(20): 4236-8, 1988 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-20539549

RESUMEN

Optical matrix-vector multiplication using four-wave mixing in a thin photorefractive GaAs crystal is demonstrated. Using a thin wafer of GaAs offers the potential to integrate the encoding spatial light modulators directly on the wave-mixing medium.

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