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1.
Appl Opt ; 62(18): 4935-4941, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37707271

RESUMO

The half-adder is one of the most useful combinational logic functions for data processing. Many research papers in the literature propose nonlinear all-optical half-adders. Few studies propose linear all-optical devices, and those that do usually employ microstructured 2D photonic crystals. This work presents the numerical acquisition of an all-optical half-adder using a linear three-core fiber device. The device presents high performance and acceptable values of fabrication and modulation tolerance. It can be made using any fiber technology and propagated by pulses of any wavelength. Depending on the type of fiber used, the precision needed to fabricate the device's smallest structures can range from 20 nm to 90 nm. This result is evidence of the possibility of obtaining nonlinear logical processing using only fiber design.

2.
Appl Opt ; 61(28): 8515-8521, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256168

RESUMO

Digital multiplexers/demultiplexers (MUX/DEMUXes) are essential for computing, data transmission, and data processing. However, research on all-optical digital MUX/DEMUXes is scarce and generally proposes single-function nonlinear devices. This work presents the numerical acquisition of all-optical digital MUX/DEMUXes using a linear three-core fiber device. Our device, called the interchanging-cores planar three-core fiber coupler, is propagated by low-powered amplitude modulated pulses, can operate with pulses of any wavelength, and can be made using any fiber technology. This result is further evidence of the possibility of obtaining logical processing, even nonlinear logical processing, using fiber-only design.

3.
Appl Opt ; 60(29): 9225-9230, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34624008

RESUMO

The growth of transmission rates in optical fibers can increase the demand for devices that perform network node processing. Usually, such devices achieve complex optical signal processing through high non-linearity effects and optoelectronic devices. In this work, we present the numerical acquisition of a configurable multi-function logic gate in which the OR and AND gates can be enabled based on the logic values entered in a selector. Our device consists of a single piece of three-core PCF, with linear pulse propagation, and without the need for any other mechanisms. This result presents evidence that information processing within functional fibers is possible and might be achieved using only fiber design.

4.
Acta Ortop Mex ; 28(1): 28-32, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-26031135

RESUMO

INTRODUCTION: Pelvic tilt is clinically assessed based on its relationship with spinal conditions, but there is little evidence from the asymptomatic-population for comparison purposes. OBJECTIVE: To analyze an asymptomatic population focusing,on pelvic asymmetries using photogrammetry. MATERIAL AND METHODS: 92 subjects (18-35 years old) underwent marking of the anterior and posterior iliac spines and were photographed. Alcimage software was used to measure the pelvic tilt angle. Other tests included: the Kolmogorov normality test, t test, Wilcoxon test, and Pearson coefficient to measure the correlation. RESULTS: 11.96% of males had anteversion and 34.78% normality; 38.04% of females had anteversion and 15.22% normality. Angles between iliacs for bilateral tilt showed no difference, but a difference was seen with the predominance of one side. For unilateral tilt a difference between illacs was seen. Good correlation of predominance versus anteversion was observed, and correlation was poor for side angles. The rest showed a weak or non-significant correlation. CONCLUSION: Tilt cannot be used individually to characterize pelvic dysfunction or pathology.


Assuntos
Pelve/anormalidades , Adolescente , Adulto , Feminino , Humanos , Masculino , Pelvimetria , Adulto Jovem
5.
J Pediatr (Rio J) ; 75(6): 477-80, 1999.
Artigo em Português | MEDLINE | ID: mdl-14685505

RESUMO

INTRODUCTION: The Imerslund-Gräsbeck syndrome is a rare hereditary autosomal recessive disease, characterized by the onset of megaloblastic anemia and asymptomatic proteinuria during the first 2 years of life. OBJECTIVE: To emphasize the importance of early detection of this disorder, due to high morbidity when not correctly treated, in addition to the necessity of screening and genetic counseling of the asymptomatic family members. METHODS: The authors report two patients, male and female, 8 and 10 years old, respectively. Their past history revealed anemia and multiple blood transfusions since their infancy. They evolved with pancytopenia during childhood and diagnosis of Severe Aplastic Anemia or Fanconi Syndrome was suspected. They were referred to the Bone Marrow Transplantation Section -HC- UFPR. RESULTS: Laboratory investigations revealed pancytopenia in peripheral blood. Bone marrow aspiration showed a marked megaloblastic erythropoiesis. Twenty-four-hour urine collection revealed proteinuria (3.0 and 5.8 g/dl respectively). Cytogenetic analysis was normal. Resolution of symptoms followed replacement therapy with parenteral vitamin B12. CONCLUSIONS: The presence of megaloblastic anemia in children should be followed by investigation of proteinuria, due to the existence of this rare disorder, that has a simple diagnosis and an effective treatment.

6.
Acta Med Port ; 2(6): 297-301, 1989.
Artigo em Português | MEDLINE | ID: mdl-2696333

RESUMO

The authors make a revision of the principles of action of the myoelectric prosthesis for the forearm amputees and describe their components. The indications and contra-indications (French law) are also referred. We can say as a conclusion that the great progress made in prosthesis in the last years were possible on account of synthetic materials and the use of electronics and miniaturised computers. However, their functional possibilities are remote when compared with the human hand. The high costs of this prosthesis are one limitation to its prescription.


Assuntos
Amputados/reabilitação , Membros Artificiais , Membros Artificiais/história , Biônica , Antebraço , Mãos , História do Século XX , Humanos , Desenho de Prótese
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