Pulsed FCAW of Martensitic Stainless Clads onto Mild Steel: Microstructure, Hardness, and Residual Stresses.

The low carbon martensitic stainless AWS 410NiMo steel has in its chemical composition 13% chromium, 4% nickel, and 0.4% molybdenum (wt.%) and is used in turbine recovery, rotors, and high-pressure steam pump housings due to its resistance to impact at low temperatures, as well as to corrosion and cavitation. Those applications of the AWS 410NiMo steel frequently demand repair, which is performed by welding or cladding. Arc welding is a well-established technique for joining materials and presents several parameters that influence the mechanical performance of the weld bead. Although numerous welding processes exist, optimizing welding parameters for specific applications and materials is always challenging. The present work deals with a systematic study to verify the correlation between the pulsed fluxed core arc welding (FCAW) parameters, namely pulse current and frequency, welding speed, and contact tip work distance (CTWD), and the bead morphology, microstructure formation, residual stress, and hardness of the martensitic clad. The substrate used was the AISI 1020 steel, and the AWS 410NiMo steel was the filler metal for clad deposition. From the initial nine (9) samples, three (3) were selected for in-depth characterization. Lower heat input resulted in lower dilution, more elevated hardness, and lower compressive residual stresses. Therefore, the results highlight the need for selecting the proper heat input, even when using a pulsed FCAW procedure, to achieve the desired performance of the clad. In the present case, a higher heat input appears to be more advantageous owing to the lower convexity index, smooth hardness transition between fusion and heat-affected zones in addition to more elevated compressive stresses.

Oil leakage induces changes in microbiomes of deep-sea sediments of Campos Basin (Brazil).

The Campos Basin (100,000 km2) is located on the continental shelf of southeastern Brazil. Despite the significant oil and gas industrial activities underway in the Campos Basin, scarce information is available regarding the hydrocarbon contents and microbial communities in the deep-sea sediments. To gain new insights on these aspects, we first obtained deep-sea sediment samples with different degrees of oil exposure. We obtained samples from a seabed fissure (N = 28), surroundings (250 m to 500 m from the fissure; N = 24), and a control area (N = 4). We used shotgun metagenomics to characterize the taxonomic and metabolic diversity and analyzed biogeochemical parameters (metal and oil concentration) of all samples. The high levels of unresolved complex mixture of hydrocarbons in the fissure indicate a potentially recent petrogenic contribution in these sediments. The fissure area was found to have a higher abundance of hydrocarbonoclastic bacterial genera and hydrocarbon degradation genes. These bacteria may be used as biosensors of sediment contamination. The effects of oil contamination, mainly around the fissure, are less clear at 250 m and 500 m, suggesting that the surroundings may not have been heavily affected by the oil leakage. Our study demonstrates that metagenomics can disclose biosensors for environmental monitoring.

Detection of hyaluronic acid receptor in human vocal folds by immunohistochemistry.

UNLABELLED: Hyaluronic acid receptor is a glycoprotein of the plasmatic membrane, and the CD44 is its representative, expressed in many cell types where it has the task of cell adhesion. AIM: the goal of the present experimental study is to investigate the possibility of using immunohistochemistry to identify the distribution of hyaluronic acid along the vocal fold. MATERIALS AND METHODS: We resected the normal vocal folds from a normal 23 year-old male black individual. The slides were analyzed by means of a histomorphometric study, comparing the color intensity in the superficial, middle and deep layers of the lamina propria. In the silanized slides we used immunohistochemistry, and evaluated the slides under light microscopy with 40x magnification, and the color changed to brown when there was a reaction with the receptor for hyaluronic acid. RESULTS: Immunohistochemical findings showed the presence of hyaluronic acid receptors in the epithelium covering the vocal fold, being more concentrated in the central region of the vocal fold. CONCLUSION: immunohistochemistry, used to assess the distribution of hyaluronic acid receptors in the central portion of the vocal fold, proved it to be present in the vocal fold epithelium and it prevailed in its middle third.

Spectrographic Acoustic Vocal Characteristics of Elderly Women Engaged in Aerobics.

OBJECTIVES: This study was carried out to characterize the voice of the elderly women engaged in aerobics through spectrographic analysis. METHODS: The vocal emission /a:/ of 58 elderly women engaged in aerobics for the spectrographic analysis of broadband (BBS) and narrowband (NBS) was collected, through the Real-Time Spectrogram of KayPENTAX program, that provides information about the glottal source, the position of the vocal tract and the characteristics of vowels and consonants. ANOVA (Análise de Variância) test was used for associations and Pearson correlation test with a significance level of 5%. RESULTS: To the BBS, the elderly women had medium intensity of the tracing color of the formants (Fs), low presence of noise, and medium definition of F1 and F2. There was a medium defining F3 and F4 and regularity for age 60 years, medium definition F4 and high regularity of the tracing for 70 years, and medium definition of F3 and F4 and regularity of the tracing for 80 years. For the NBS, the elderly women had medium intensity of tracing color, little presence of noise, harmonic substitutions by noise and subharmonic; 60 and 80 years had medium definition of harmonics and regularity of tracing and high definition; and regular for 70 years. For 70 and 80 years, there was a presence of harmonics and medium presence for 60 years. There was a negative correlation between F2 and the group of 60 years and F3 with the general age. CONCLUSIONS: Even with myofunctional, structural, and functional changes of the larynx caused by advancing age, which may affect the vocal characteristics, the elderly women of this study showed few changes in tracing spectrogram.

Vocal Characteristics of Elderly Women Engaged in Aerobics in Private Institutions of Salvador, Bahia.

PURPOSE: To characterize the voice of elderly people engaged in aerobics. METHODS: Collection of phonation /a:/ from 58 elderly people engaged in aerobics for perceptual voice analysis (RASATI scale) and computed acoustics (Multi Dimensional Voice Program Advanced, software of Kay Pentax®, that analyzes up to 33 measures, proposing normal ranges according to sex). The Spearman correlation test was used, with significance level of 5%. RESULTS: The association between auditory-perceptual assessment of voice and acoustic parameters was not statistically significant but showed less vocal quality deviations. The association between acoustic measures and age was only statistically significant result for the measurement of fundamental frequency (f0) and maximum f0 (fhi). There was no correlation between time of aerobics and acoustic measures, but there was correlation of those measurements with age. There was a statistically significant positive correlation between f0 and fhi with minimal roughness and standard deviation of f0 with hoarseness, breathiness, and asthenia; jitter and shimmer measures with hoarseness, breathiness, and asthenia; noise measurements with hoarseness, breathiness, and harshness; measures of breaking voice hoarseness and breathiness; measures of voiceless segments with hoarseness and asthenia; measures of subharmonic with hoarseness; and measures of vocal tremor with breathiness, asthenia, and instability. There was a significant negative correlation between minimum f0 with breathiness; jitter measures with tension; and soft phonation index with roughness and instability. CONCLUSIONS: Elderly women engaged in aerobics showed mostly normal voice, with most values of acoustic measures within normal and positive correlations between perceptual and auditory vocals and acoustic aspects that suggest instability, noise, and vocal tremor.

Immunohistochemistry as a method to study elastic fibers of human vocal fold.

AIM: Verify the use of immunohistochemistry as a method to measure all forms of elastic fibers at human vocal folds. STUDY DESIGN: Transversal cohort. MATERIAL AND METHOD: We collected vocal folds following these criterion: age between 25 and 40, Caucasian men, dead by gun shot, within 12 hours of death, without instrumentation of the larynx or suspicion of neck injury and without mucosal lesions noted by microscopy. Ten vocal folds were collected and one, of a man aged 28 years, was selected to study. The vocal fold was transversely cut in 9 regions and in each segment three slides were made. These slides were stained by Verhoeff and Weighert's resorcin-fuchsin and used for immunohistochemistry. The elastic compound was measured by colorimetric software analysis. RESULTS: In Verhoeff and Weighert's resorcin-fuchsin, the intermediate and deep layer showed values higher than those of the superficial layer. The amount of tropoelastin identified by the antibody at the superficial layer was close to those of intermediate and deep layer. CONCLUSION: Immunohistochemistry is a method that can identify and measure all forms of elastic fibers at human vocal fold.

Detecção de receptor de ácido hialurônico em prega vocal humana por método imunohistoquímico / Detection of hyaluronic acid receptor in human vocal folds by immunohistochemistry

O receptor do ácido Hialurônico é uma glicoproteína da membrana plasmática, sendo o principal o CD44, e está expresso em vários tipos de células onde possui a função de adesão celular. OBJETIVO: Estudar a possibilidade de empregar o método imunohistoquímico para identificar a distribuição dos receptores de ácido hialurônico ao longo da prega vocal humana. MATERIAL E MÉTODOS: Foram ressecadas as pregas vocais normais de um indivíduo de 23 anos, sexo masculino, cor negra. As lâminas foram analisadas por meio de estudo histomorfométrico, comparando-se a intensidade das cores nas camadas superficial, média e profunda da lâmina própria. Nas lâminas silanizadas foi utilizado método imunohistoquímico, sendo avaliadas através de microscopia óptica com aumento 40 vezes, obtendo coloração marrom onde houve a reação com receptor para ácido hialurônico. RESULTADOS: Os achados imunohistoquímicos mostraram presença de receptores para ácido hialurônico no epitélio de cobertura da prega vocal tendo maior concentração na região central da prega vocal. CONCLUSÃO: A técnica de imunohistoquímica, utilizada para avaliar a distribuição dos receptores para ácido hialurônico na pregas vocais humanas, mostrou sua disposição em epitélio da prega vocal e predomínio no terço médio, em relação às demais regiões na prega vocal estudada.

Hyaluronic acid receptor is a glycoprotein of the plasmatic membrane, and the CD44 is its representative, expressed in many cell types where it has the task of cell adhesion. AIM: the goal of the present experimental study is to investigate the possibility of using immunohistochemistry to identify the distribution of hyaluronic acid along the vocal fold. MATERIALS AND METHODS: We resected the normal vocal folds from a normal 23 year-old male black individual. The slides were analyzed by means of a histomorphometric study, comparing the color intensity in the superficial, middle and deep layers of the lamina propria. In the silanized slides we used immunohistochemistry, and evaluated the slides under light microscopy with 40x magnification, and the color changed to brown when there was a reaction with the receptor for hyaluronic acid. RESULTS: Immunohistochemical findings showed the presence of hyaluronic acid receptors in the epithelium covering the vocal fold, being more concentrated in the central region of the vocal fold. CONCLUSION: immunohistochemistry, used to assess the distribution of hyaluronic acid receptors in the central portion of the vocal fold, proved it to be present in the vocal fold epithelium and it prevailed in its middle third.

Imunohistoquímica como método de estudo das fibras elásticas em prega vocal humana / Immunohistochemistry as a method to study elastic fibers of human vocal fold

OBJETIVO: O objetivo deste trabalho é o de verificar a aplicabilidade do método imunohistoquímico na quantificação das diferentes formas das fibras elásticas em prega vocal humana. FORMA DE ESTUDO: coorte transversal. MATERIAL E MÉTODO: Foram seguidos os seguintes critérios de inclusão: idade entre 25 e 40 anos, gênero masculino, cor branca, morte causada por ferimento de arma de fogo, menos de doze horas de morte, ausência de intubação traqueal e de trauma na região cervical e que, por análise microscópica, não apresentassem qualquer alteração da mucosa das pregas vocais. Por estes critérios dez pregas vocais foram obtidas e selecionou-se, aleatoriamente, uma prega vocal que pertencia a um indivíduo de 28 anos. A prega vocal foi transversalmente seccionada em nove regiões e três cortes de cada fragmento foram utilizados para a realização das colorações Verhoeff e resorcina-fuchsina de Weighert e para a realização do estudo imunohistoquímico. Realizou-se quantificação colorimétrica das fibras elásticas. RESULTADO: As camadas intermediária e profunda da prega vocal apresentam valores muito superiores aos da camada superficial, nas colorações histológicas. A quantidade de tropoelastina identificada pelos anticorpos não apresentou grandes diferenças entre os valores da camada superficial e os da camada intermediária e profunda. CONCLUSÃO: A imunohistoquímica é uma técnica que identifica, em prega vocal humana, todas as formas de fibras elásticas e que também possibilita a realização de medidas objetivas.