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1.
Light Sci Appl ; 9(1): 183, 2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33298828

RESUMEN

Dynamic axial focusing functionality has recently experienced widespread incorporation in microscopy, augmented/virtual reality (AR/VR), adaptive optics and material processing. However, the limitations of existing varifocal tools continue to beset the performance capabilities and operating overhead of the optical systems that mobilize such functionality. The varifocal tools that are the least burdensome to operate (e.g. liquid crystal, elastomeric or optofluidic lenses) suffer from low (≈100 Hz) refresh rates. Conversely, the fastest devices sacrifice either critical capabilities such as their dwelling capacity (e.g. acoustic gradient lenses or monolithic micromechanical mirrors) or low operating overhead (e.g. deformable mirrors). Here, we present a general-purpose random-access axial focusing device that bridges these previously conflicting features of high speed, dwelling capacity and lightweight drive by employing low-rigidity micromirrors that exploit the robustness of defocusing phase profiles. Geometrically, the device consists of an 8.2 mm diameter array of piston-motion and 48-µm-pitch micromirror pixels that provide 2π phase shifting for wavelengths shorter than 1100 nm with 10-90% settling in 64.8 µs (i.e., 15.44 kHz refresh rate). The pixels are electrically partitioned into 32 rings for a driving scheme that enables phase-wrapped operation with circular symmetry and requires <30 V per channel. Optical experiments demonstrated the array's wide focusing range with a measured ability to target 29 distinct resolvable depth planes. Overall, the features of the proposed array offer the potential for compact, straightforward methods of tackling bottlenecked applications, including high-throughput single-cell targeting in neurobiology and the delivery of dense 3D visual information in AR/VR.

2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3289-3292, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018707

RESUMEN

Untethered, wireless peripheral nerve recording for prosthetic control requires multi-implant communications at high data rates. This work presents a multiple-access ultrasonic uplink data communication channel comprised of 4 free-floating implants and a single-element external transducer. Using code-division multiple access (CDMA), overall channel data rates of up to 784 kbps were measured, and a machine-learning assisted decoder improved BER by >100x. Compared with prior art, this work incorporates the largest number of implants at the highest data rate and spectral efficiency reported.


Asunto(s)
Algoritmos , Ultrasonido , Aprendizaje Automático , Prótesis e Implantes , Transductores
3.
Am J Physiol Lung Cell Mol Physiol ; 309(12): L1447-54, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26432869

RESUMEN

Pulmonary lymphangioleiomyomatosis (LAM), a rare progressive lung disease associated with mutations of the tuberous sclerosis complex 2 (Tsc2) tumor suppressor gene, manifests by neoplastic growth of LAM cells, induction of cystic lung destruction, and respiratory failure. LAM severity correlates with upregulation in serum of the prolymphangiogenic vascular endothelial growth factor D (VEGF-D) that distinguishes LAM from other cystic diseases. The goals of our study was to determine whether Tsc2 deficiency upregulates VEGF-D, and whether axitinib, the Food and Drug Administration-approved small-molecule inhibitor of VEGF receptor (VEGFR) signaling, will reduce Tsc2-null lung lesion growth in a mouse model of LAM. Our data demonstrate upregulation of VEGF-D in the serum and lung lining in mice with Tsc2-null lesions. Progressive growth of Tsc2-null lesions induces recruitment and activation of inflammatory cells and increased nitric oxide production. Recruited cells isolated from the lung lining of mice with Tsc2-null lesions demonstrate upregulated expression of provasculogenic Vegfa, prolymphangiogenic Figf, and proinflammatory Nos2, Il6, and Ccl2 genes. Importantly, axitinib is an effective inhibitor of Tsc2-null lesion growth and inflammatory cell recruitment, which correlates with reduced VEGF-D levels in serum and lung lining. Our data demonstrate that pharmacological inhibition of VEGFR signaling with axitinib inhibits Tsc2-null lesion growth, attenuates recruitment and activation of inflammatory cells, and reduces VEGF-D levels systemically and in the lung lining. Our study suggests a potential therapeutic benefit of inhibition of VEGFR signaling for treatment of LAM.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Imidazoles/farmacología , Indazoles/farmacología , Pulmón/efectos de los fármacos , Linfangioleiomiomatosis/tratamiento farmacológico , Receptores de Factores de Crecimiento Endotelial Vascular/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Animales , Axitinib , Línea Celular Tumoral , Quimiocina CCL2/metabolismo , Modelos Animales de Enfermedad , Femenino , Pulmón/metabolismo , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Linfangioleiomiomatosis/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Óxido Nítrico Sintasa de Tipo II/metabolismo , Proteína 2 del Complejo de la Esclerosis Tuberosa , Regulación hacia Arriba/efectos de los fármacos , Factor D de Crecimiento Endotelial Vascular/metabolismo
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