ABSTRACT
In this work, an approach is proposed to solve binary combinatorial problems using continuous metaheuristics. It focuses on the importance of binarization in the optimization process, as it can have a significant impact on the performance of the algorithm. Different binarization schemes are presented and a set of actions, which combine different transfer functions and binarization rules, under a selector based on reinforcement learning is proposed. The experimental results show that the binarization rules have a greater impact than transfer functions on the performance of the algorithms and that some sets of actions are statistically better than others. In particular, it was found that sets that incorporate the elite or elite roulette binarization rule are the best. Furthermore, exploration and exploitation were analyzed through percentage graphs and a statistical test was performed to determine the best set of actions. Overall, this work provides a practical approach for the selection of binarization schemes in binary combinatorial problems and offers guidance for future research in this field.
ABSTRACT
El SARS-CoV-2 es un virus de afectación sistémica que impacta con gran intensidad en el sistema inmunológico; esto permite que virus de naturaleza latente, como el virus de Varicela Zoster (VVZ), tengan oportunidad de reactivarse y agravar el cuadro respiratorio con afectaciones cutáneas, mucosas y neurológicas. Se presenta un caso de Zoster sine herpete, durante la convalecencia del SARS-CoV-2, en un paciente masculino de 43 años, que acudió a consulta por dolor precordial de gran intensidad, sensación de escozor en tórax posterior y dificultad respiratoria; 10 días después de prueba de hisopado nasofaríngeo positiva para antígeno de SARS-CoV-2. Es importante no olvidar la probabilidad de presentaciones atípicas de virus latentes con el fin de realizar un diagnóstico y tratamiento oportuno a los pacientes.
SARS-CoV-2 is a systemic virus that has a strong impact on the immune system; this allows latent viruses, such as varicella-zoster virus (VZV), to reactivate and aggravate the respiratory symptoms with cutaneous, mucosal and neurological involvement. We present a case of Zoster sine herpete, during convalescence from SARS-CoV-2, in a 43-year-old male patient who presented with severe precordial pain, stinging sensation in the posterior thorax and respiratory distress; 10 days after a positive nasopharyngeal swab test for SARS-CoV-2 antigen. It is important not to forget the probability of atypical presentations of latent viruses to make a timely diagnosis and treatment of patients.
Subject(s)
Humans , Male , Adult , Zoster Sine Herpete/complications , SARS-CoV-2/immunologyABSTRACT
OBJECTIVE: Herpes zoster virus can cause inflammatory neuropathy of the facial nerve. However, studies evaluating the prevalence of this agent in peripheral facial palsy are heterogeneous regarding sample group selection, laboratory analysis method and variables studied. In addition, there are a lack of epidemiological data in the Brazilian population on this serological phenomenon in peripheral facial palsy. This study estimated herpes zoster reactivation prevalence in serological samples through chemiluminescence immunoassay for quantitative determination of specific antibodies directed against the virus. METHODS: This cross-sectional study sought to determine the prevalence of viral reactivation by herpes zoster in subjects with idiopathic peripheral facial palsy through analysis of serological samples over a year. RESULTS: Forty-seven patients (32 females and 15 males) participated. Severe paralysis was more common in older patients (p = 0.017). Facial pain (p = 0.02) and vertigo (p = 0.001) were related to a worse evolution of facial palsy. The rate of serological reactivation of the virus was 12.76 per cent. CONCLUSION: The rate of serological reactivation of herpes virus in idiopathic peripheral facial palsy in our population is similar to foreign literature data, suggesting similar aetiological mechanisms in the genesis of this morbidity.
Subject(s)
Bell Palsy , Facial Paralysis , Herpes Zoster , Aged , Antibodies, Viral , Bell Palsy/epidemiology , Cross-Sectional Studies , Facial Paralysis/epidemiology , Female , Herpes Zoster/complications , Herpes Zoster/diagnosis , Herpes Zoster/epidemiology , Herpesvirus 3, Human/physiology , Humans , Male , PrevalenceSubject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Hematopoietic Stem Cell Transplantation , Hydrazines/administration & dosage , Multiple Myeloma/therapy , Neoplasm Recurrence, Local/drug therapy , Triazoles/administration & dosage , Dexamethasone/administration & dosage , Humans , Male , Multiple Myeloma/pathology , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/pathology , Oligopeptides/administration & dosage , Transplantation, Homologous , Treatment OutcomeABSTRACT
The present study aimed to investigate whether or not the so-called "bouba-kiki" effect is mediated by speech-specific representations. Sine-wave versions of naturally produced pseudowords were used as auditory stimuli in an implicit association task (IAT) and an explicit cross-modal matching (CMM) task to examine cross-modal shape-sound correspondences. A group of participants trained to hear the sine-wave stimuli as speech was compared to a group that heard them as non-speech sounds. Sound-shape correspondence effects were observed in both groups and tasks, indicating that speech-specific processing is not fundamental to the "bouba-kiki" phenomenon. Effects were similar across groups in the IAT, while in the CMM task the speech-mode group showed a stronger effect compared with the non-speech group. This indicates that, while both tasks reflect auditory-visual associations, only the CMM task is additionally sensitive to associations involving speech-specific representations.
Subject(s)
Speech Perception , Speech , Hearing , Humans , SoundABSTRACT
Systemic sclerosis sine scleroderma (ssSSc) is a form of systemic sclerosis that is characterized by Raynaud's phenomenon (RP), visceral involvement without thickening of skin and anticentromere antibodies (ACA). We studied 10 ssSsc patients with a prevalence of 2%. The clinical signs were: RP 9/10, esophageal manifestations 8/10, pulmonary arterial hypertension 4/10, interstitial lung disease 4/10, cardiac signs 3/10 and ACA 8/10. CONCLUSION: In patients with RP, esophageal dysmotility, interstitial lung disease and pulmonary arterial hypertension should be tested for ACA in order to establish a prompt diagnosis and treatment of ssSSc.
Subject(s)
Scleroderma, Systemic/diagnosis , Adult , Aged , Female , Humans , Male , Mexico , Middle Aged , Retrospective Studies , Scleroderma, Systemic/complications , Scleroderma, Systemic/pathologyABSTRACT
BACKGROUND Chagas disease is highly prevalent in Latin America, and vector control is the most effective control strategy to date. We have previously shown that liquid chromatography tandem mass spectrometry (LC-MS/MS) is a valuable tool for identifying triatomine vector blood meals. OBJECTIVES The purpose of this study was to determine blood meal detection ability as a function of method [polymerase chain reaction (PCR) vs. LC-MS/MS], time since feeding, and the effect of molting in mouse-fed triatomine insect vectors targeting hemoglobin and albumin proteins with LC-MS/MS and short interspersed nuclear elements (SINE)-based PCR. METHODS We experimentally fed Triatoma protracta on mice and used LC-MS/MS to detect hemoglobin and albumin peptides over time post-feeding and post-molting (≤ 12 weeks). We compared LC-MS/MS results with those of a standard PCR method based on SINEs. FINDINGS Hemoglobin-based LC-MS/MS detected blood meals most robustly at all time points post-feeding. Post-molting, no blood meals were detected with PCR, whereas LC-MS/MS detected mouse hemoglobin and albumin up to 12 weeks. MAIN CONCLUSIONS In our study, the hemoglobin signature in the insect abdomen lasted longer than that of albumin and DNA. LC-MS/MS using hemoglobin shows promise for identifying triatomine blood meals over long temporal scales and even post-molting. Clarifying the frequency of blood-feeding on different hosts can foster our understanding of vector behavior and may help devise sounder disease-control strategies, including Ecohealth (community based ecosystem management) approaches.
Subject(s)
Humans , Chagas Disease/therapy , Chagas Disease/epidemiology , Hemoglobins , Serum AlbuminABSTRACT
La Esclerodermia es una patología poco frecuente que afecta principalmente la piel, de ahí su nombre. Desde ese punto de vista existen diferentes clasificaciones siendo las más frecuentes: forma Difusa y Limitada. Existe también otra forma de presenta-ción, muy infrecuente y difícil de identificar: la esclerosis sistémica sin esclerodermia (eSSe). En este reporte presentamos el caso de una paciente de 50 años, que cursa con injuria renal aguda de origen inexplicado con algunos elementos de laboratorio de microangiopatía trombótica, sin clínica sugerente de esclerosis sistémica progre-siva y con laboratorio inicial difícil, lo que retrasó el diagnóstico y por ende el trata-miento. En este caso se obtiene el diagnóstico de crisis renal esclerodérmica, por los hallazgos compatibles de microangiopatía trombótica arrojados por la biopsia renal.
Systemic sclerosis is a rare connective tissue disease that is characterized by thickening of the skin (scleroderma). The disease has 2 main presentations forms: diffuse and limited. However, it can also manifest without scleroderma, known as systemic sclerosis sine scleroderma (ssSSc). In this report, we describe the case of a 50 years female who debut with acute renal injury and possible microangiopathy thrombotic elements in laboratory findings, in absence of signs of scleroderma at physical examination or initial laboratory test results, causing the delay of accurate diagnosis and management. Renal biopsy findings were compatible with thrombotic microangiopathy and renal sclerodermic crisis, which guided the diagnosis and subsequent management.
Subject(s)
Humans , Female , Middle Aged , Scleroderma, Systemic/diagnosis , Scleroderma, Systemic/therapy , Scleroderma, Systemic/classification , Scleroderma, Systemic/mortality , Scleroderma, Systemic/pathology , Acute Kidney Injury , Kidney/pathologyABSTRACT
Introducción: Herpes Zoster es la reactivación del Virus Varicela Zóster en los ganglios sensoriales y/o autonómicos, típicamente caracterizado por dolor profundo de distribución dermatómica y erupciones vesiculares en piel. De manera infrecuente, puede presentarse el Zoster Sine Herpete, condición en la cual se presenta la distribución dermatómica del dolor en ausencia de lesiones dérmicas, convirtiendo el diagnóstico en un reto clínico. Caso clínico: Hombre de 69 años con dolor periorbitario, epifora, ptosis y pérdida de la aducción del ojo derecho. Los estudios imagenológicos y de laboratorio fueron normales, descartando así las principales causas de parálisis del nervio oculomotor. Se hizo diagnóstico presuntivo de Zoster Sine Herpete y se inició prueba terapéutica con valaciclovir, observándose resolución total de la sintomatología seis semanas después. Discusión: Este caso puede ser el primero en describir una parálisis parcial dolorosa del nervio oculomotor como única manifestación clínica de la reactivación del Virus Varicela Zóster y busca alertar al personal médico sobre una enfermedad latente que hace de sus reapariciones una gama de presentaciones no siempre fáciles de identificar.
Introduction: Herpes zoster is the reactivation of the varicella zoster virus in the sensorial and/ or autonomic ganglia, typically characterized by cutaneous vesicular eruptions and deep pain with dermatomal distribution. Infrequently can occur the Zoster Sine Herpete; condition in which there is dermatomal distribution of the pain in absence of dermic injuries, making the diagnosis a challenge for the clinician. Case report: 69 years old man with periorbital pain, epiphora, ptosis and loss of adduction of the right eye. The imaging and laboratory studies were normal, excluding with this the main causes of oculomotor nerve palsy. A presumptive diagnosis of Zoster Sine Herpete was done and a therapeutic test with valacyclovir was initiated, showing complete resolution 6 weeks later without sequelaes. Discussion: This case may be the first in describing partial painful oculomotor nerve palsy as the only manifestation of the varicella zoster virus reactivation and seeks to aware the medical staff about a latent disease that makes from his reappearances a wide range of presentations not always easily to identify.
ABSTRACT
Several studies suggest a strong familial aggregation for cluster headache (CH), but so far none of them have included subjects with probable cluster headache (PCH) in accordance with the International Classification of Headache Disorders. Objective To identify cases of probable cluster headache and to assess the familial aggregation of cluster headache by including these subjects. Method Thirty-six patients attending a headache consultation and diagnosed with trigeminal autonomic headaches were subjected to a questionnaire-based interview. A telephone interview was also applied to all the relatives who were pointed out as possibly affected as well as to some of the remaining relatives. Results Twenty-four probands fulfilled the criteria for CH or PCH; they had 142 first-degree relatives, of whom five were found to have CH or PCH, including one case of CH sine headache. The risk for first-degree relatives was observed to be increased by 35- to 46-fold. Conclusion Our results suggest a familial aggregation of cluster headache in the Portuguese population. .
Diversos artigos sugerem uma significativa agregação familiar da cefaleia em salvas (CH) embora nenhum tenha incluído indivíduos com provável cefaleia em salvas (PCH), segundo critérios da Classificação Internacional de Cefaleias (ICHD-II). Objetivo Encontrar casos de provável cefaleia em salvas e avaliar a agregação familiar da cefaleia em salvas incluindo também esses indivíduos. Método Foi aplicado um questionário por telefone a 36 doentes que frequentaram uma Consulta de Cefaleias com diagnóstico de cefaleia trigémino-autonómica. Todos os familiares de primeiro grau referidos como possivelmente afetados e alguns dos restantes foram entrevistados por telefone. Resultados Em 24 doentes foi diagnosticada CH ou PCH e estes tinham 142 familiares de primeiro grau, cinco dos quais foram diagnosticados como CH ou PCH, incluindo um caso de CH sem cefaleias. O risco para familiares de primeiro grau foi 35-46 vezes superior ao da população geral. Conclusão Nossos resultados sugerem a existência de uma agregação familiar da cefaleia em salvas na população portuguesa. .
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Cluster Headache/genetics , Family , Age of Onset , Pedigree , Risk Assessment , Risk Factors , Surveys and QuestionnairesABSTRACT
OBJECTIVE: Systemic sclerosis sine scleroderma (ssSSc) is an infrequent SSc variant characterized by visceral and immunological manifestations of SSc in the absence of clinically detectable skin involvement. We sought to delineate the characteristics of ssSSc in a cohort of Brazilian patients and contrast them with those in the literature. METHODS: SSc patients seen at two academic medical centres in Brazil were retrospectively analysed. Patients were classified as ssSSc if they presented with RP, positive ANAs and at least one visceral involvement typical of SSc in the absence of skin thickening. Demographics, clinical and laboratory data were obtained by chart review. Literature review was performed by searching available original studies up until June 2012. RESULTS: Among the 947 consecutive patients with SSc, 79 (8.3%) were classified as ssSSc. Oesophagus was the most frequently affected organ (83.1%), followed by pulmonary involvement (63.2%). Compared with the limited cutaneous form of SSc, telangiectasia was the only variable significantly different after multivariate logistic regression analyses (odds ratio 0.46; 95% CI 0.27, 0.81). Compared with the diffuse cutaneous form of SSc, multivariate analyses revealed that ssSSc patients were less likely to be male (odds ratio 0.15; 95% CI 0.04, 0.57), have digital ulcers (odds ratio 0.26; 95% CI 0.13, 0.51) or anti-Scl70 antibodies (odds ratio 0.19; 95% CI 0.07, 0.55) and less frequently treated with CYC (odds ratio 0.23; 95% CI 0.12, 0.43). These features were comparable to those in the published literature. CONCLUSION: In this series, patients with ssSSc had a relatively mild disease with good prognosis.
Subject(s)
Scleroderma, Systemic/epidemiology , Scleroderma, Systemic/pathology , Academic Medical Centers , Adult , Age Distribution , Brazil/epidemiology , Cohort Studies , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Multivariate Analysis , Prognosis , Rare Diseases , Retrospective Studies , Scleroderma, Systemic/classification , Severity of Illness Index , Sex DistributionABSTRACT
Background: Short interspersed nuclear elements (SINEs) are transposable elements which are transcribed by RNA polymerase III and widespread in mammalian genomes. Can-SINE is a family of SINE sequences specific to carnivores, predominant in their genomes and present in high copy numbers. The aim of this study was to characterize sequences of Can-SINEs integrated into sequences of endogenous retroviruses (ERVs) from Brazilian wild cats Puma concolor and Leopardus geoffroyi. Additionally, these sequences are considered from some perspectives of their evolution. Material, Methods and Results: By using PCR and sequencing to screen for ERVs within the genomes of L. geoffroyi and P. concolor, two new ERV sequences were amplified with an insertion around 220 nucleotides long, similar to published carnivore SINEs. The sequences were further identified and characterized using a combination of BLAST, BLAT searches and phylogenetic analyses. The results showed that SINE sequences integrated into the ERV from P. concolor (SINE_Pco) and L. geoffroyi (SINE_Lg) are lysine-tRNA derived. These sequences presented a typical RNA polymerase III-specific internal promoter sequence followed by a microsatellite region (TC)n and by an A/T-rich tail with the polyadenylation signal AATAAA. BLAST searches using the whole sequence of L. geoffroyi clone as query (ERV plus SINE) detected two sequences which
Background: Short interspersed nuclear elements (SINEs) are transposable elements which are transcribed by RNA polymerase III and widespread in mammalian genomes. Can-SINE is a family of SINE sequences specific to carnivores, predominant in their genomes and present in high copy numbers. The aim of this study was to characterize sequences of Can-SINEs integrated into sequences of endogenous retroviruses (ERVs) from Brazilian wild cats Puma concolor and Leopardus geoffroyi. Additionally, these sequences are considered from some perspectives of their evolution. Material, Methods and Results: By using PCR and sequencing to screen for ERVs within the genomes of L. geoffroyi and P. concolor, two new ERV sequences were amplified with an insertion around 220 nucleotides long, similar to published carnivore SINEs. The sequences were further identified and characterized using a combination of BLAST, BLAT searches and phylogenetic analyses. The results showed that SINE sequences integrated into the ERV from P. concolor (SINE_Pco) and L. geoffroyi (SINE_Lg) are lysine-tRNA derived. These sequences presented a typical RNA polymerase III-specific internal promoter sequence followed by a microsatellite region (TC)n and by an A/T-rich tail with the polyadenylation signal AATAAA. BLAST searches using the whole sequence of L. geoffroyi clone as query (ERV plus SINE) detected two sequences which
ABSTRACT
Background: Short interspersed nuclear elements (SINEs) are transposable elements which are transcribed by RNA polymerase III and widespread in mammalian genomes. Can-SINE is a family of SINE sequences specific to carnivores, predominant in their genomes and present in high copy numbers. The aim of this study was to characterize sequences of Can-SINEs integrated into sequences of endogenous retroviruses (ERVs) from Brazilian wild cats Puma concolor and Leopardus geoffroyi. Additionally, these sequences are considered from some perspectives of their evolution. Material, Methods and Results: By using PCR and sequencing to screen for ERVs within the genomes of L. geoffroyi and P. concolor, two new ERV sequences were amplified with an insertion around 220 nucleotides long, similar to published carnivore SINEs. The sequences were further identified and characterized using a combination of BLAST, BLAT searches and phylogenetic analyses. The results showed that SINE sequences integrated into the ERV from P. concolor (SINE_Pco) and L. geoffroyi (SINE_Lg) are lysine-tRNA derived. These sequences presented a typical RNA polymerase III-specific internal promoter sequence followed by a microsatellite region (TC)n and by an A/T-rich tail with the polyadenylation signal AATAAA. BLAST searches using the whole sequence of L. geoffroyi clone as query (ERV plus SINE) detected two sequences which
Background: Short interspersed nuclear elements (SINEs) are transposable elements which are transcribed by RNA polymerase III and widespread in mammalian genomes. Can-SINE is a family of SINE sequences specific to carnivores, predominant in their genomes and present in high copy numbers. The aim of this study was to characterize sequences of Can-SINEs integrated into sequences of endogenous retroviruses (ERVs) from Brazilian wild cats Puma concolor and Leopardus geoffroyi. Additionally, these sequences are considered from some perspectives of their evolution. Material, Methods and Results: By using PCR and sequencing to screen for ERVs within the genomes of L. geoffroyi and P. concolor, two new ERV sequences were amplified with an insertion around 220 nucleotides long, similar to published carnivore SINEs. The sequences were further identified and characterized using a combination of BLAST, BLAT searches and phylogenetic analyses. The results showed that SINE sequences integrated into the ERV from P. concolor (SINE_Pco) and L. geoffroyi (SINE_Lg) are lysine-tRNA derived. These sequences presented a typical RNA polymerase III-specific internal promoter sequence followed by a microsatellite region (TC)n and by an A/T-rich tail with the polyadenylation signal AATAAA. BLAST searches using the whole sequence of L. geoffroyi clone as query (ERV plus SINE) detected two sequences which
ABSTRACT
Background: Short interspersed nuclear elements (SINEs) are transposable elements which are transcribed by RNA polymerase III and widespread in mammalian genomes. Can-SINE is a family of SINE sequences specific to carnivores, predominant in their genomes and present in high copy numbers. The aim of this study was to characterize sequences of Can-SINEs integrated into sequences of endogenous retroviruses (ERVs) from Brazilian wild cats Puma concolor and Leopardus geoffroyi. Additionally, these sequences are considered from some perspectives of their evolution. Material, Methods and Results: By using PCR and sequencing to screen for ERVs within the genomes of L. geoffroyi and P. concolor, two new ERV sequences were amplified with an insertion around 220 nucleotides long, similar to published carnivore SINEs. The sequences were further identified and characterized using a combination of BLAST, BLAT searches and phylogenetic analyses. The results showed that SINE sequences integrated into the ERV from P. concolor (SINE_Pco) and L. geoffroyi (SINE_Lg) are lysine-tRNA derived. These sequences presented a typical RNA polymerase III-specific internal promoter sequence followed by a microsatellite region (TC)n and by an A/T-rich tail with the polyadenylation signal AATAAA. BLAST searches using the whole sequence of L. geoffroyi clone as query (ERV plus SINE) detected two sequences which were highly similar to the cougar (P. concolor) and the domestic cat. However, the SINE from Leopardus geoffroyi is not present in these related sequences. On the other hand, during searches using the whole sequence of the P. concolor clone as query, we found the same SINE insertion in a very similar ERV from domestic cat. All insertions occurred in the RT domain, but SINE_Lg was integrated in a distinct site when compared to SINE_Pco. Another interesting difference between these SINE sequences was that the statistics reported in BLAST searches recovered a much higher number of hits from the domestic cat genome using SINE_Lg as seed than in searches for sequences related to SINE_Pco. The phylogenetic tree based on the SINE fragment grouped these new SINE sequences with Can-SINEs from felids. Within this major clade SINE_Lg and SINE_Pco are related to different lineages of felids Can-SINEs. Discussion: In this study we showed that two different sequences from felid endogenous retrovirus harbor Can-SINE sequences. These insertions are not surprising taking account that ~11% of domestic cat genome is composed of SINE sequences and they are ubiquitous in felid genomes. Furthermore, the insertions of SINEs into the ERV sequences reported here are not unique events. However, they are curious insertions representing genomic fossils and a little piece of felid history. Based on the results of the phylogenetic analyses and position of the integration sites, we suggest that SINE_Lg and SINE_Pco represent independent integration events originated by derived copies from different progenitors. We hypothesized that SINE_Lg is a "young" integration due to the absence of highly similar ERVs from Puma concolor and Felis catus. This lineage may be recently active in felid genomes given that we found very similar MegaBLAST hits at EST database from domestic cat. Instead, SINE_Pco seems to be "old", sharing an identical insertion site to ERVs from domestic cat and its lineage could be inactive in felids considering that any MegaBLAST hits resulted from EST database searches. The latter suggests an integration event in an ancestor species at least 6.7 million years ago, which represents the split between puma and domestic cat lineages.
Subject(s)
Animals , Endogenous Retroviruses , Short Interspersed Nucleotide Elements/genetics , Felis/genetics , Puma/geneticsABSTRACT
O objetivo deste estudo foi medir a função de sensibilidade ao contraste (FSC) de adultos jovens para frequências espaciais de grades senoidais verticais em condições de luminância fotópica e escotópica. Utilizou-se o método psicofísico da escolha forçada para estimativa da sensibilidade ao contraste para as frequências de 0,6, 2,5 e 5,0 cpg. Todos os participantes apresentavam acuidade visual normal ou corrigida e estavam livres de doenças oculares identificáveis. As análises estatísticas mostraram que houve diferenças entre as condições de luminância e que os adultos foram mais sensíveis às frequências média e alta na condição de luminância fotópica. Esses resultados indicam que as características do sistema visual humano para detectar frequências espaciais em condições de luminância fotópica e escotópica passam por mecanismos distintos que tornam possível a diferenciação de contraste.
The aim of this study was to measure the contrast sensitivity function (CSF) of young adults for spatial frequencies of vertical sine-wave gratings in terms of photopic and scotopic luminance. We used the forced-choice psychophysical method to estimate contrast sensitivity for frequencies of 0.6, 2.5 and 5.0 cpd. All participants had normal or corrected acuity and they were free of ocular pathologies. Statistical analysis showed that there were differences between the conditions of luminance, where adults were more sensitive to middle and high frequencies in the photopic luminance condition. These results indicate that the characteristics of human visual system to detect spatial frequencies in photopic conditions of luminance and scotopic pass through distinct mechanisms that make possible the differentiation of contrast.
El objetivo de este estudio fue medir la función de sensibilidad al contraste (FSC) de los adultos jóvenes para frecuencias espaciales de las verticales redes sinusoidales en condiciones de luminosidad fotópica y escotópica. Se utilizó el método psicofísico de elección forzada para estimar la sensibilidad al contraste para las frecuencias de 0,6, 2,5 y 5,0 cpg. Todos los participantes presentaban acuidad visual normal o corigida y estaban libres de patología ocular. El análisis estadístico mostró que hay diferencias entre las condiciones de luminancia, y que los adultos son más sensibles a las frecuencias medias y altas en la condición de luminancia fotópica. Estos resultados indican que las características del sistema visual humano para la detección de frecuencias espaciales en condiciones de luminancia fotópica y escotópica pasan por diferentes mecanismos que hacen posible la diferenciación de contraste.
ABSTRACT
O objetivo deste estudo foi medir a função de sensibilidade ao contraste (FSC) de adultos jovens para frequências espaciais de grades senoidais verticais em condições de luminância fotópica e escotópica. Utilizou-se o método psicofísico da escolha forçada para estimativa da sensibilidade ao contraste para as frequências de 0,6, 2,5 e 5,0 cpg. Todos os participantes apresentavam acuidade visual normal ou corrigida e estavam livres de doenças oculares identificáveis. As análises estatísticas mostraram que houve diferenças entre as condições de luminância e que os adultos foram mais sensíveis às frequências média e alta na condição de luminância fotópica. Esses resultados indicam que as características do sistema visual humano para detectar frequências espaciais em condições de luminância fotópica e escotópica passam por mecanismos distintos que tornam possível a diferenciação de contraste.(AU)
The aim of this study was to measure the contrast sensitivity function (CSF) of young adults for spatial frequencies of vertical sine-wave gratings in terms of photopic and scotopic luminance. We used the forced-choice psychophysical method to estimate contrast sensitivity for frequencies of 0.6, 2.5 and 5.0 cpd. All participants had normal or corrected acuity and they were free of ocular pathologies. Statistical analysis showed that there were differences between the conditions of luminance, where adults were more sensitive to middle and high frequencies in the photopic luminance condition. These results indicate that the characteristics of human visual system to detect spatial frequencies in photopic conditions of luminance and scotopic pass through distinct mechanisms that make possible the differentiation of contrast.(AU)
El objetivo de este estudio fue medir la función de sensibilidad al contraste (FSC) de los adultos jóvenes para frecuencias espaciales de las verticales redes sinusoidales en condiciones de luminosidad fotópica y escotópica. Se utilizó el método psicofísico de elección forzada para estimar la sensibilidad al contraste para las frecuencias de 0,6, 2,5 y 5,0 cpg. Todos los participantes presentaban acuidad visual normal o corigida y estaban libres de patología ocular. El análisis estadístico mostró que hay diferencias entre las condiciones de luminancia, y que los adultos son más sensibles a las frecuencias medias y altas en la condición de luminancia fotópica. Estos resultados indican que las características del sistema visual humano para la detección de frecuencias espaciales en condiciones de luminancia fotópica y escotópica pasan por diferentes mecanismos que hacen posible la diferenciación de contraste.(AU)
ABSTRACT
O objetivo deste trabalho foi comparar a percepção visual de contraste de adultos sem a ingestão de álcool e após a ingestão moderada de álcool - 0,09 por cento Blood Alcohol Concentration (BAC), através da Função de Sensibilidade ao Contraste (FSC). Participaram dos experimentos cinco voluntárias, na faixa etária de 21 a 30 anos, com acuidade visual normal ou corrigida. Para medir a FSC, foram usados estímulos de grade senoidal radial de frequências de 0,25; 2 e 8 ciclos por grau de ângulo visual. Utilizou-se um delineamento experimental com medidas repetidas e o método psicofísico da escolha forçada. Os resultados demonstraram efeito significante de participantes (F4, 55 = 25,518; p < 0,001), de frequências (F2, 110 = 172,288; p < 0,001) e de interação entre frequências x condições x participantes (F8, 110 = 26,806; p < 0,001). Este estudo preliminar sugere alterações na FSC relacionadas à ingestão moderada de álcool.
The aim of this study was to compare the visual perception of contrast in adults with no alcohol intake, and after moderate consumption of alcohol by them - 0.09 percent Blood Alcohol Concentration (BAC), through the Contrast Sensitivity Function (CSF). Participated in the experiments five volunteers, aged 21-30 years, with normal or corrected visual acuity. To measure the CSF, we used radial sine-wave grating stimuli of frequencies of 0.25; 2 e 8 cycles per degree of visual angle. We used an experimental design or sketch, with repeated measures, and a forced-choice psychophysical method. The results showed significant effect of subjects (F4, 55 = 25,518; p < 0,001), of frequencies (F2, 110 = 172,288; p < 0,001), and of the interaction between frequencies versus conditions versus subjects (F8, 110 = 26,806; p < 0,001). This preliminary study suggests changes in CSF, related to moderate alcohol consumption.
L'objectif de cette étude était comparer la perception visuelle de contraste chez des adultes sans consommation d'alcool et, dans le cas d'autres, après une consommation modérée d'alcool - 0,09 percent taux d'alcoolémie (TA), grâce à la fonction de sensibilité au contraste (FSC). Cinq volontaires âgés de 21-30 ans et avec d'acuité visuelle normale ou corrigée ont participé aux expériences. Pour mesurer la FSC, nous avons utilisé la grille sinusoïdale radiale de 0,25; 2 et 8 cycles par degré de l'angle visuel. Nous avons utilisé aussi un modèle expérimental, avec des mesures répétées, et une méthode psychophysique de choix forcé. Les résultats ont montré d'effet significatif dans les sujets (F4, 55 = 25,518; p < 0,001), dans les fréquences (F2, 110 = 172,288; p < 0,001) et dans l'interaction entre les fréquences, les conditions et les sujets (F8, 110 = 26,806; p < 0,001). Cette étude préliminaire suggère des changements dans la FSC, liés à la consommation modérée d'alcool.
El objetivo de este estudio fue comparar la percepción visual de contraste en los adultos, sin consumo de alcohol y después de un consumo moderado de alcohol por parte de ellos - 0,09 por ciento de concentración de alcohol en sangre (BAC), a través de la función de sensibilidad al contraste (CSF). Participaron en los experimentos cinco voluntarias, con edades entre 21 y 30 años, con valores normales de agudeza visual. Para medir la CSF, se utilizaron radiales de onda sinusoidal rejilla de estímulos de frecuencias de 0,25, 2 e 8 ciclos por grado de ángulo visual. Se utilizó un diseño experimental o croquis, con medidas repetidas y un método psicofísico de la elección forzada. Los resultados mostraron efecto significativo de sujetos (F4, 55 = 25.518, p < 0.001), de las frecuencias (F2, 110 = 172.288, p < 0,001) y de la interacción entre las frecuencias en comparación con las condiciones en comparación con sujetos (F8, 110 = 26,806; p < 0,001). Este estudio preliminar sugiere cambios en el LCR, relacionados con el consumo moderado de alcohol.
ABSTRACT
O objetivo deste trabalho foi comparar a percepção visual de contraste de adultos sem a ingestão de álcool e após a ingestão moderada de álcool 0,09% Blood Alcohol Concentration (BAC), através da Função de Sensibilidade ao Contraste (FSC). Participaram dos experimentos cinco voluntárias, na faixa etária de 21 a 30 anos, com acuidade visual normal ou corrigida. Para medir a FSC, foram usados estímulos de grade senoidal radial de frequências de 0,25; 2 e 8 ciclos por grau de ângulo visual. Utilizou-se um delineamento experimental com medidas repetidas e o método psicofísico da escolha forçada. Os resultados demonstraram efeito significante de participantes (F4, 55 = 25,518; p < 0,001), de frequências (F2, 110 = 172,288; p < 0,001) e de interação entre frequências x condições x participantes (F8, 110 = 26,806; p < 0,001). Este estudo preliminar sugere alterações na FSC relacionadas à ingestão moderada de álcool(AU)
The aim of this study was to compare the visual perception of contrast in adults with no alcohol intake, and after moderate consumption of alcohol by them 0.09% Blood Alcohol Concentration (BAC), through the Contrast Sensitivity Function (CSF). Participated in the experiments five volunteers, aged 21-30 years, with normal or corrected visual acuity. To measure the CSF, we used radial sine-wave grating stimuli of frequencies of 0.25; 2 e 8 cycles per degree of visual angle. We used an experimental design or sketch, with repeated measures, and a forced-choice psychophysical method. The results showed significant effect of subjects (F4, 55 = 25,518; p < 0,001), of frequencies (F2, 110 = 172,288; p < 0,001), and of the interaction between frequencies versus conditions versus subjects (F8, 110 = 26,806; p < 0,001). This preliminary study suggests changes in CSF, related to moderate alcohol consumption(AU)
L'objectif de cette étude était comparer la perception visuelle de contraste chez des adultes sans consommation d'alcool et, dans le cas d'autres, après une consommation modérée d'alcool 0,09% taux d'alcoolémie (TA), grâce à la fonction de sensibilité au contraste (FSC). Cinq volontaires âgés de 21-30 ans et avec d'acuité visuelle normale ou corrigée ont participé aux expériences. Pour mesurer la FSC, nous avons utilisé la grille sinusoïdale radiale de 0,25; 2 et 8 cycles par degré de l'angle visuel. Nous avons utilisé aussi un modèle expérimental, avec des mesures répétées, et une méthode psychophysique de choix forcé. Les résultats ont montré d'effet significatif dans les sujets (F4, 55 = 25,518; p < 0,001), dans les fréquences (F2, 110 = 172,288; p < 0,001) et dans l'interaction entre les fréquences, les conditions et les sujets (F8, 110 = 26,806; p < 0,001). Cette étude préliminaire suggère des changements dans la FSC, liés à la consommation modérée d'alcool(AU)
El objetivo de este estudio fue comparar la percepción visual de contraste en los adultos, sin consumo de alcohol y después de un consumo moderado de alcohol por parte de ellos 0,09% de concentración de alcohol en sangre (BAC), a través de la función de sensibilidad al contraste (CSF). Participaron en los experimentos cinco voluntarias, con edades entre 21 y 30 años, con valores normales de agudeza visual. Para medir la CSF, se utilizaron radiales de onda sinusoidal rejilla de estímulos de frecuencias de 0,25, 2 e 8 ciclos por grado de ángulo visual. Se utilizó un diseño experimental o croquis, con medidas repetidas y un método psicofísico de la elección forzada. Los resultados mostraron efecto significativo de sujetos (F4, 55 = 25.518, p < 0.001), de las frecuencias (F2, 110 = 172.288, p < 0,001) y de la interacción entre las frecuencias en comparación con las condiciones en comparación con sujetos (F8, 110 = 26,806; p < 0,001). Este estudio preliminar sugiere cambios en el LCR, relacionados con el consumo moderado de alcohol(AU)
Subject(s)
Humans , Female , Adult , Visual Perception , Alcohol Drinking/psychology , Contrast SensitivityABSTRACT
O objetivo deste estudo foi caracterizar a função de sensibilidade ao contraste (FSC) de adolescentes e adultos jovens. Mediu-se a FSC para estímulos de grade senoidal linear com frequências espaciais de 0,25, 1,0, 2,0 e 8,0 cpg, utilizando o método psicofísico da escolha forçada com duas alternativas temporais. As medidas foram obtidas com visão binocular e luminância média de 42,6 cd/m². Todos os participantes apresentavam acuidade visual normal e estavam livres de doenças oculares identificáveis. As análises apontaram diferenças significantes entre os dois grupos nas frequências baixas, médias e altas. Os adultos foram mais sensíveis que os adolescentes nas frequências baixas (0,25 cpg), e os adolescentes foram mais sensíveis que os adultos nas frequências médias e altas (2,0 e 8,0 cpg). Esses resultados sugerem que o processo de desenvolvimento e maturação da percepção visual de contraste interage de maneira distinta com os mecanismos que processam frequências espaciais.
The aim of this study was to characterize the contrast sensitivity function (CSF) of adolescents and young adults. Was measured FSC for linear sine-wave grating stimuli with spatial frequencies of 0.25, 1.0, 2.0 and 8.0 cpd, using the forced-choice psychophysic method with two alternatives temporal. The measurements were performed with binocular vision and the medium luminance of 42.6 cd/m². All participants had normal acuity and were free of ocular pathology. The analysis showed significant differences between the two groups in the low medium and high frequencies. The adults were more sensitive than adolescents in low frequencies (0.25 cpd) and adolescents were more sensitive than adults in middle and high frequencies (2.0 and 8.0 cpd). These results suggest that the process of development and maturation of the visual perception of contrast interacts differently with the mechanisms that process spatial frequencies.
El objetivo de este estudio fue caracterizar la función de sensibilidad al contraste (FSC) de los adolescentes y adultos jóvenes. Se midió la FSC para estímulos de onda senoidal con frecuencias espaciales lineal de 0,25, 1,0, 2,0 y 8,0 cpg, utilizando el método psicofísico de la elección forzada con dos alternativas. Las mediciones se realizaron con la visión binocular y la luminancia media del 42,6 cd/m². Todos los participantes presentaban acuidad visual normal y estaban libres de enfermedades oculares identificables. El análisis mostró diferencias significativas entre los dos grupos en las frecuencias de bajo, medio y alto. Los adultos eran más sensibles que los adolescentes en las frecuencias bajas (0,25 cpg) y los adolescentes eran más sensibles que los adultos en las frecuencias medias y altas (2,0 y 8,0 cpg). Estos resultados sugieren que el proceso de desarrollo y maduración de la percepción visual de contraste interactúa de manera diferente con los mecanismos que las frecuencias de proceso espacial.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Contrast Sensitivity , Nervous System , Visual Perception , Psychophysics/classification , Psychophysics/statistics & numerical data , Psychophysics/methodsABSTRACT
O objetivo deste estudo foi caracterizar a função de sensibilidade ao contraste (FSC) de adolescentes e adultos jovens. Mediu-se a FSC para estímulos de grade senoidal linear com frequências espaciais de 0,25, 1,0, 2,0 e 8,0 cpg, utilizando o método psicofísico da escolha forçada com duas alternativas temporais. As medidas foram obtidas com visão binocular e luminância média de 42,6 cd/m². Todos os participantes apresentavam acuidade visual normal e estavam livres de doenças oculares identificáveis. As análises apontaram diferenças significantes entre os dois grupos nas frequências baixas, médias e altas. Os adultos foram mais sensíveis que os adolescentes nas frequências baixas (0,25 cpg), e os adolescentes foram mais sensíveis que os adultos nas frequências médias e altas (2,0 e 8,0 cpg). Esses resultados sugerem que o processo de desenvolvimento e maturação da percepção visual de contraste interage de maneira distinta com os mecanismos que processam frequências espaciais.(AU)
The aim of this study was to characterize the contrast sensitivity function (CSF) of adolescents and young adults. Was measured FSC for linear sine-wave grating stimuli with spatial frequencies of 0.25, 1.0, 2.0 and 8.0 cpd, using the forced-choice psychophysic method with two alternatives temporal. The measurements were performed with binocular vision and the medium luminance of 42.6 cd/m². All participants had normal acuity and were free of ocular pathology. The analysis showed significant differences between the two groups in the low medium and high frequencies. The adults were more sensitive than adolescents in low frequencies (0.25 cpd) and adolescents were more sensitive than adults in middle and high frequencies (2.0 and 8.0 cpd). These results suggest that the process of development and maturation of the visual perception of contrast interacts differently with the mechanisms that process spatial frequencies.(AU)
El objetivo de este estudio fue caracterizar la función de sensibilidad al contraste (FSC) de los adolescentes y adultos jóvenes. Se midió la FSC para estímulos de onda senoidal con frecuencias espaciales lineal de 0,25, 1,0, 2,0 y 8,0 cpg, utilizando el método psicofísico de la elección forzada con dos alternativas. Las mediciones se realizaron con la visión binocular y la luminancia media del 42,6 cd/m². Todos los participantes presentaban acuidad visual normal y estaban libres de enfermedades oculares identificables. El análisis mostró diferencias significativas entre los dos grupos en las frecuencias de bajo, medio y alto. Los adultos eran más sensibles que los adolescentes en las frecuencias bajas (0,25 cpg) y los adolescentes eran más sensibles que los adultos en las frecuencias medias y altas (2,0 y 8,0 cpg). Estos resultados sugieren que el proceso de desarrollo y maduración de la percepción visual de contraste interactúa de manera diferente con los mecanismos que las frecuencias de proceso espacial.(AU)