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1.
Front Neurosci ; 14: 667, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848531

RESUMEN

In resource-constrained environments, such as low-power edge devices and smart sensors, deploying a fast, compact, and accurate intelligent system with minimum energy is indispensable. Embedding intelligence can be achieved using neural networks on neuromorphic hardware. Designing such networks would require determining several inherent hyperparameters. A key challenge is to find the optimum set of hyperparameters that might belong to the input/output encoding modules, the neural network itself, the application, or the underlying hardware. In this work, we present a hierarchical pseudo agent-based multi-objective Bayesian hyperparameter optimization framework (both software and hardware) that not only maximizes the performance of the network, but also minimizes the energy and area requirements of the corresponding neuromorphic hardware. We validate performance of our approach (in terms of accuracy and computation speed) on several control and classification applications on digital and mixed-signal (memristor-based) neural accelerators. We show that the optimum set of hyperparameters might drastically improve the performance of one application (i.e., 52-71% for Pole-Balance), while having minimum effect on another (i.e., 50-53% for RoboNav). In addition, we demonstrate resiliency of different input/output encoding, training neural network, or the underlying accelerator modules in a neuromorphic system to the changes of the hyperparameters.

2.
Ophthalmology ; 126(1): 156-170, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29361356

RESUMEN

PURPOSE: To describe the study protocol and baseline characteristics of the African Descent and Glaucoma Evaluation Study (ADAGES) III. DESIGN: Cross-sectional, case-control study. PARTICIPANTS: Three thousand two hundred sixty-six glaucoma patients and control participants without glaucoma of African or European descent were recruited from 5 study centers in different regions of the United States. METHODS: Individuals of African descent (AD) and European descent (ED) with primary open-angle glaucoma (POAG) and control participants completed a detailed demographic and medical history interview. Standardized height, weight, and blood pressure measurements were obtained. Saliva and blood samples to provide serum, plasma, DNA, and RNA were collected for standardized processing. Visual fields, stereoscopic disc photographs, and details of the ophthalmic examination were obtained and transferred to the University of California, San Diego, Data Coordinating Center for standardized processing and quality review. MAIN OUTCOME MEASURES: Participant gender, age, race, body mass index, blood pressure, history of smoking and alcohol use in POAG patients and control participants were described. Ophthalmic measures included intraocular pressure, visual field mean deviation, central corneal thickness, glaucoma medication use, or past glaucoma surgery. Ocular conditions, including diabetic retinopathy, age-related macular degeneration, and past cataract surgery, were recorded. RESULTS: The 3266 ADAGES III study participants in this report include 2146 AD POAG patients, 695 ED POAG patients, 198 AD control participants, and 227 ED control participants. The AD POAG patients and control participants were significantly younger (both, 67.4 years) than ED POAG patients and control participants (73.4 and 70.2 years, respectively). After adjusting for age, AD POAG patients had different phenotypic characteristics compared with ED POAG patients, including higher intraocular pressure, worse visual acuity and visual field mean deviation, and thinner corneas (all P < 0.001). Family history of glaucoma did not differ between AD and ED POAG patients. CONCLUSIONS: With its large sample size, extensive specimen collection, and deep phenotyping of AD and ED glaucoma patients and control participants from different regions in the United States, the ADAGES III genomics study will address gaps in our knowledge of the genetics of POAG in this high-risk population.


Asunto(s)
Negro o Afroamericano/genética , Glaucoma de Ángulo Abierto/genética , Polimorfismo de Nucleótido Simple , Anciano , Constitución Corporal , Estudios de Casos y Controles , Estudios Transversales , Femenino , Interacción Gen-Ambiente , Estudio de Asociación del Genoma Completo , Genotipo , Glaucoma de Ángulo Abierto/diagnóstico , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Fenotipo , Proyectos de Investigación , Agudeza Visual/fisiología , Campos Visuales/fisiología , Población Blanca/genética
3.
Ophthalmology ; 126(1): 38-48, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30352225

RESUMEN

PURPOSE: To find genetic contributions to glaucoma in African Americans. DESIGN: Cross-sectional, case-control study. PARTICIPANTS: One thousand eight hundred seventy-five primary open-angle glaucoma (POAG) patients and 1709 controls, self-identified as being of African descent (AD), from the African Descent and Glaucoma Evaluation Study (ADAGES) III and Wake Forest School of Medicine. METHODS: MegaChip genotypes were imputed to Thousand Genomes data. Association of single nucleotide polymorphisms (SNPs) with POAG and advanced POAG was tested by linear mixed model correcting for relatedness and population stratification. Genetic risk scores were tested by receiver operator characteristic curves (ROC-AUCs). MAIN OUTCOME MEASURES: Primary open-angle glaucoma defined by visual field loss without other nonocular conditions (n = 1875). Advanced POAG was defined by age-based mean deviation of visual field (n = 946). RESULTS: Eighteen million two hundred eighty-one thousand nine hundred twenty SNPs met imputation quality of r2 > 0.7 and minor allele frequency > 0.005. Association of a novel locus, EN04, was observed for advanced POAG (rs185815146 ß, 0.36; standard error, 0.065; P < 3×10-8). For POAG, an AD signal was observed at the 9p21 European descent (ED) POAG signal (rs79721419; P < 6.5×10-5) independent of the previously observed 9p21 ED signal (rs2383204; P < 2.3×10-5) by conditional analyses. An association with POAG in FNDC3B (rs111698934; P < 3.9×10-5) was observed, not in linkage disequilibrium (LD) with the previously reported ED SNP. Additional previously identified loci associated with POAG in persons of AD were: 8q22, AFAP1, and TMC01. An AUC of 0.62 was observed with an unweighted genetic risk score comprising 11 SNPs in candidate genes. Two additional risk scores were studied by using a penalized matrix decomposition with cross-validation; risk scores of 50 and 400 SNPs were identified with ROC of AUC = 0.74 and AUC = 0.94, respectively. CONCLUSIONS: A novel association with advanced POAG in the EN04 locus was identified putatively in persons of AD. In addition to this finding, this genome-wide association study in POAG patients of AD contributes to POAG genetics by identification of novel signals in prior loci (9p21), as well as advancing the fine mapping of regions because of shorter average LD (FNDC3B). Although not useful without confirmation and clinical trials, the use of genetic risk scores demonstrated that considerable AD-specific genetic information remains in these data.


Asunto(s)
Negro o Afroamericano/genética , Glaucoma de Ángulo Abierto/genética , Fosfopiruvato Hidratasa/genética , Polimorfismo de Nucleótido Simple , Anciano , Estudios de Casos y Controles , Estudios Transversales , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genotipo , Glaucoma de Ángulo Abierto/diagnóstico , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Curva ROC
4.
J Invest Dermatol ; 136(6): 1172-1181, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26896775

RESUMEN

Delivery of vaccine formulations into the dermis using antigen-coated microneedle patches is a promising and safe approach because of efficient antigen delivery and safety. We evaluated an intradermal vaccine using HIV-1 p24 Gag peptide-conjugated polypropylene sulfide nanoparticles to induce immunity against HIV-1. This peptide-conjugated polypropylene sulfide nanoparticle formulation did not accelerate the maturation of blood- or skin-derived subsets of dendritic cells, either generated in vitro or purified ex vivo, despite efficient uptake in the absence of adjuvant. Moreover, dendritic cell-mediated capture of particulate antigen in this form induced potent HIV-1-specific CD4(+) T-cell responses, as well as B-cell-mediated antibody production. Nanoparticle-based intradermal antigen delivery may therefore provide a new option in the global effort to develop an effective vaccine against HIV-1.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Sistemas de Liberación de Medicamentos/métodos , VIH-1/inmunología , Inmunidad Celular/efectos de los fármacos , Vacunas/administración & dosificación , Animales , Linfocitos T CD4-Positivos/efectos de los fármacos , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Infecciones por VIH/prevención & control , VIH-1/efectos de los fármacos , Humanos , Nanopartículas/administración & dosificación , Polipropilenos/farmacología , Sulfuros/farmacología
5.
J Natl Med Assoc ; 107(2): 130-2, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27269502

RESUMEN

As Acquired Immunodeficiency Disease (AIDS) turns thirty-years old, much progress has been made. 56,000 new cases of the Human Immunodeficiency Virus (HIV) infection are expected in Americans this year. At least half or more will be in African Americans. Reports of the association between syphilis and HIV infection are well documented. We present a case of bilateral optic neuritis and panuveitis as the initial presentation in a previously undiagnosed patient with human immunodeficiency virus (HIV) and syphilis.

6.
J Natl Med Assoc ; 101(4): 373-6, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19397231

RESUMEN

We report a 67-year-old female diabetic with homonymous hemianopia as the presenting sign of nonketotic hyperglycemia. Magnetic resonance imaging (MRI) was abnormal with diffuse bilateral hyperintense white matter changes. A follow-up MRI scan 15 years later showed persisting abnormality. Her hemianopic visual field loss was reversed after correction of her hyperglycemia. Diabetes mellitus should be considered with the sudden onset of a homonymous hemianopia.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Hemianopsia/etiología , Hiperglicinemia no Cetósica/complicaciones , Anciano , Encéfalo/patología , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Femenino , Hemianopsia/diagnóstico , Humanos , Hiperglicinemia no Cetósica/diagnóstico , Hiperglicinemia no Cetósica/terapia , Imagen por Resonancia Magnética
7.
J Natl Med Assoc ; 100(4): 435-8, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18481484

RESUMEN

UNLABELLED: One-thousand-eighty-one rural and urban inhabitants of Venezuela were discovered to have good uncorrected visual acuity. This was especially noted among the males who were examined. More myopia was seen than previously reported, while earlier presbyopia was confirmed. There was a relatively low prevalence of glaucoma among men and women. Correction of refractive errors, cataracts, glaucoma and pterygia remains a challenge. OBJECTIVE: To determine the frequency of ocular disease in rural and urban Venezuela. DESIGN: Participants in a cross-sectional health screening study were examined. The main outcome measured was external eye disease: allergic conjunctivitis, dry eyes and pterygia. RESULTS: A total of 1,281 individuals participated. All agreed to screening and eye examinations. Open-angle glaucoma was present in 1.2% of women and 1% of men. For participants age > 45, this increased to 1.9% of women and 2.8% of men. CONCLUSIONS: Rural and urban inhabitants of Venezuela were determined to have good uncorrected visual acuity, especially among males. More myopia was noted than previously reported, while earlier presbyopia was confirmed. There was a relatively low frequency of glaucoma among men and women as compared to Barbados, and a U.S.-based study of Mexican Americans.


Asunto(s)
Oftalmopatías/diagnóstico , Oftalmopatías/epidemiología , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Estudios Transversales , Técnicas de Diagnóstico Oftalmológico , Oftalmopatías/fisiopatología , Femenino , Humanos , Lactante , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Prevalencia , Población Rural , Factores Sexuales , Población Urbana , Venezuela/epidemiología , Agudeza Visual
8.
J Natl Med Assoc ; 100(5): 572-4, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18507211

RESUMEN

Lateral rectus muscle (LRM) palsy due to a nuclear or fascicular sixth nerve lesion is rare as the presenting sign of multiple sclerosis (MS). It is more common to find this palsy in the company of other nearby cranial nerves deficits. Facial numbness in association with a LRM palsy or paresis may go unappreciated and therefore underreported. We report an unusual patient with a LRM palsy, facial anesthesia, ataxia and as the initial manifestation of MS. There was a demyelinating lesion in the pons seen on magnetic resonance imaging (MRI).


Asunto(s)
Enfermedades del Nervio Abducens/etiología , Ataxia/etiología , Parálisis Facial/etiología , Esclerosis Múltiple/complicaciones , Enfermedades del Nervio Abducens/fisiopatología , Adulto , Ataxia/fisiopatología , Parálisis Facial/fisiopatología , Femenino , Humanos , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/fisiopatología
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