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1.
Nature ; 633(8030): 560-566, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39261726

RESUMO

Artificial Intelligence (AI) is the domain of large resource-intensive data centres that limit access to a small community of developers1,2. Neuromorphic hardware promises greatly improved space and energy efficiency for AI but is presently only capable of low-accuracy operations, such as inferencing in neural networks3-5. Core computing tasks of signal processing, neural network training and natural language processing demand far higher computing resolution, beyond that of individual neuromorphic circuit elements6-8. Here we introduce an analog molecular memristor based on a Ru-complex of an azo-aromatic ligand with 14-bit resolution. Precise kinetic control over a transition between two thermodynamically stable molecular electronic states facilitates 16,520 distinct analog conductance levels, which can be linearly and symmetrically updated or written individually in one time step, substantially simplifying the weight update procedure over existing neuromorphic platforms3. The circuit elements are unidirectional, facilitating a selector-less 64 × 64 crossbar-based dot-product engine that enables vector-matrix multiplication, including Fourier transform, in a single time step. We achieved more than 73 dB signal-to-noise-ratio, four orders of magnitude improvement over the state-of-the-art methods9-11, while consuming 460× less energy than digital computers12,13. Accelerators leveraging these molecular crossbars could transform neuromorphic computing, extending it beyond niche applications and augmenting the core of digital electronics from the cloud to the edge12,13.


Assuntos
Redes Neurais de Computação , Cinética , Inteligência Artificial , Razão Sinal-Ruído , Ligantes , Termodinâmica , Análise de Fourier , Processamento de Sinais Assistido por Computador/instrumentação
2.
Neuroophthalmology ; 45(6): 403-406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720272

RESUMO

Hepatitis B virus (HBV) infection is a major public health problem. Liver diseases such as cirrhosis and hepatocellular carcinoma are the main causes of mortality and morbidity associated with this viral infection. Ocular manifestations may also arise during the course of HBV infection. We herein present a 44-year-old male with bilateral optic neuropathy revealing chronic HBV infection.

3.
Neuroophthalmology ; 44(1): 34-37, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32076447

RESUMO

A 32-year-old man presented to our clinic with complaint of vision loss in both eyes (oculus utro; OU). Past medical history revealed that he had been exposed to high-voltage electrical current that passed through the temporal region of the head 2 months ago. Slit-lamp examination demonstrated cortico-nuclear cataract and mature cataract in his right eye (oculus dexter; OD) and left eye (oculus sinister; OS), respectively. On fundus examination, a macular hole was observed in OD. Optic atrophy and foveal atrophy were observed in the left fundus examination after cataract surgery. Simultaneous cataract, maculopathy and optic atrophy may occur after high-voltage electrical current injury. Therefore, clinicians should perform detailed anterior and posterior segment examinations in such patients.

4.
Neurol Sci ; 39(7): 1309-1312, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29623524

RESUMO

We present an interesting case with nonarteritic anterior ischemic optic neuropathy (NAION) accompanied by Buerger's disease. A 43-year-old man was referred to our neuro-ophthalmology clinic with a complaint of visual deterioration in the left eye that started 5 days ago. He suffered from Buerger's disease, and he had acute pain in the right lower limb below the knee. His best corrected visual acuity was 10/10 in the right eye and 2/10 in the left eye by Snellen chart. There was a relative afferent pupil defect in the left eye. The right optic disc was normal on fundus examination, and blurring, hemorrhagic swelling was found at the left optic disc. Inferior altitudinal visual field defect was observed in the left eye. Neurological examination was normal. Computed tomography angiography scan revealed occlusion in the right posterior tibial artery. Brain imaging and laboratory tests such as blood analyses, genetic screening, coagulation, and lipid panels were unremarkable. NAION may occur in patients with Buerger's disease, but it is extremely rare. Therefore, clinicians should be aware of this rare association.


Assuntos
Neuropatia Óptica Isquêmica/etiologia , Tromboangiite Obliterante/complicações , Adulto , Diagnóstico Diferencial , Olho/diagnóstico por imagem , Humanos , Extremidade Inferior/diagnóstico por imagem , Masculino , Neuropatia Óptica Isquêmica/diagnóstico , Neuropatia Óptica Isquêmica/tratamento farmacológico , Tromboangiite Obliterante/diagnóstico , Tromboangiite Obliterante/tratamento farmacológico , Acuidade Visual
5.
Saudi J Ophthalmol ; 36(3): 327-334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276250

RESUMO

PURPOSE: To investigate optical coherence tomography (OCT) biomarker data on visual recovery in treatment-naïve diabetic macular edema (DME) and follow the results of intravitreal ranibizumab (RNB), aflibercept (AFL), and dexamethasone (DEX) implant administration within the 1st year of the pro re nata treatment regimen. METHODS: One hundred and twenty eyes of 102 patients were enrolled in the study. The patients medical records were analyzed retrospectively. Best-corrected visual acuity (BCVA), central macular thickness (CMT), type of DME, presence of subretinal fluid, number and localization of hyperreflective dots, vitreomacular interface disorders, disorganization of the retinal inner layer (DRIL), inner segment/outer segment (IS/OS) junction-external limiting membrane (ELM) status, intraretinal cyst diameter and localization, and subfoveal choroidal thickness were examined in all patients. RESULTS: A statistically significant increase in BCVA and a decrease in CMT were detected in all treatment groups. When cases were evaluated in terms of BCVA before and after treatment, statistically significant differences were observed in the RNB and AFL groups at 1 and 4 months and in the DEX group during the 1st year. In terms of OCT biomarkers, visual recovery was obtained in cases of intact IS/OS-ELM and non-DRIL patients. In the serous macular detachment group, more visual gain was achieved with the RNB (1 and 4 months) and AFL (1, 4, and 6 months) agents compared to the DEX implant. On the other hand, in the group with cystoid macular edema, more visual gain was achieved with RNB compared to the DEX implant in all months, but more visual gain was achieved only in the 1st month with AFL administration. CONCLUSION: Significant improvement was achieved for both BCVA and CMT in all treatment groups. We expect that OCT-based prognostic factors will become more important in the treatment of DME and will be determining factors in the choice of treatment.

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