Estudio de correlación entre diferentes escalas que miden la dependencia al tabaquismo / Study of correlation between different scales that measure smoking dependence

Objetivo: Analizar la correlación entre los grados de dependencia al tabaquismo medidos mediante los test: Fagerström de dependencia a la nicotina (FTND), dependencia conductual Glover-Nilsson (GN-SBQ) y una medida de la dependencia autopercibida (DA). Diseño: Estudio observacional descriptivo transversal. Emplazamiento: Centro de salud urbano. Participantes: Varones y mujeres de 18 a 65 años, fumadores a diario, escogidos mediante muestreo consecutivo no aleatorizado. Intervenciones: Auto cumplimentación de diversos cuestionarios presentados a través de un dispositivo electrónico (del propio usuario o proporcionado por el centro de salud). Mediciones principales: Edad, sexo y dependencia a la nicotina evaluada mediante FTND, GN-SBQ y DA. Análisis estadístico con SPSS® v.15.0: estadística descriptiva, análisis de correlación de Pearson y análisis de conformidad. Resultados: Se incluyeron 214 individuos (54,7% mujeres) y una edad media de 52 años (rango: 27-65). Dependiendo del test utilizado, obtuvimos resultados dispares, en el nivel de dependencia alta/muy alta medido: FTND 17,3%; TG- SBQ 15,4% y DA 69,6%. La correlación de los 3 test fue de magnitud moderada (r≈0,5). Al evaluar la concordancia, comparando el FTND con la DA, en el 70,6% de los fumadores los niveles de dependencia no coincidían, sugiriendo FTND un grado de dependencia más leve que lo estimado mediante la DA. GN-SBQ vs. FTND, mostró conformidad (los niveles de dependencia eran equivalentes) en el 44,4%, mientras que en el 40,7% FTND infraestimó la dependencia respecto al GN-SBQ. Comparando DA vs. GN-SBQ, en el 64% GN-SBQ infraestimó y hubo conformidad en el 34,1%. Conclusiones: Los pacientes que consideran una DA alta/muy alta es 4 veces superior respecto a GN-SBQ y FTND; siendo FTND el más exigente categorizando a los pacientes con dependencia muy alta. Considerar únicamente FTND de 7 para financiar la deshabituación tabáquica puede excluir a pacientes subsidiarios recibir tratamiento.(AU)

Objective: To analyze the correlation between the degrees of smoking dependence, measured with the Fagerström Test Nicotine Dependence (FTND), Glover-Nilsson Smoking Behavioral Dependence (GN-SBQ) and a measure of self-perceived-dependence (SPD). Design: Cross-sectional descriptive observational study. Site: Urban primary health-care center. Participants: Men and women between 18 and 65 years old, daily smokers, selected by non-random consecutive sampling. Interventions: Self-administration of various questionnaires though an electronic device. Main measurements: Age, sex and nicotine dependence assessed by: FTND, GN-SBQ and SPD. Statistical analysis, with SPSS 15.0: descriptive statistics, Pearson correlation analysis and conformity analysis. Results: Two hundred fourteen smokers were included, 54.7% were women. Median age 52 years (range: 27-65). Depending on the test used, different results of the high/very high degree of dependence were found: FTND 17.3%, GN-SBQ 15.4% and SPD 69.6%. A moderate magnitude (r≈0.5) correlation between the 3 test was found. When assessing concordance, comparing the FTND with SPD, 70.6% of smokers didn’t coincide in the severity of dependence, reporting a milder degree of dependence with the FTND than with SPD. Comparing GN-SBQ versus FTND, showed conformity in 44.4% of patients while in 40.7%, the FTND underestimated the severity of dependence. Likewise, when comparing SPD with the GN-SBQ, in the 64% GN-SBQ underestimates, while in 34.1% smokers conformity was demonstrated. Conclusions: The number of patients who consider their SPD to be high/very high was four times higher compared to the GN-SBQ or the FNTD; the latter, being the most demanding, categorizing patients with very high dependence. Requiring a FTND score greater than 7 to prescribe drugs for smoking cessation may exclude subsidiary patients from receiving treatment.(AU)

[Study of correlation between different scales that measure smoking dependence]. / Estudio de correlación entre diferentes escalas que miden la dependencia al tabaquismo.

OBJECTIVE: To analyze the correlation between the degrees of smoking dependence, measured with the Fagerström Test Nicotine Dependence (FTND), Glover-Nilsson Smoking Behavioral Dependence (GN-SBQ) and a measure of self-perceived-dependence (SPD). DESIGN: Cross-sectional descriptive observational study. SITE: Urban primary health-care center. PARTICIPANTS: Men and women between 18 and 65 years old, daily smokers, selected by non-random consecutive sampling. INTERVENTIONS: Self-administration of various questionnaires though an electronic device. MAIN MEASUREMENTS: Age, sex and nicotine dependence assessed by: FTND, GN-SBQ and SPD. Statistical analysis, with SPSS 15.0: descriptive statistics, Pearson correlation analysis and conformity analysis. RESULTS: Two hundred fourteen smokers were included, 54.7% were women. Median age 52 years (range: 27-65). Depending on the test used, different results of the high/very high degree of dependence were found: FTND 17.3%, GN-SBQ 15.4% and SPD 69.6%. A moderate magnitude (r≈0.5) correlation between the 3 test was found. When assessing concordance, comparing the FTND with SPD, 70.6% of smokers didn't coincide in the severity of dependence, reporting a milder degree of dependence with the FTND than with SPD. Comparing GN-SBQ versus FTND, showed conformity in 44.4% of patients while in 40.7%, the FTND underestimated the severity of dependence. Likewise, when comparing SPD with the GN-SBQ, in the 64% GN-SBQ underestimates, while in 34.1% smokers conformity was demonstrated. CONCLUSIONS: The number of patients who consider their SPD to be high/very high was four times higher compared to the GN-SBQ or the FNTD; the latter, being the most demanding, categorizing patients with very high dependence. Requiring a FTND score greater than 7 to prescribe drugs for smoking cessation may exclude subsidiary patients from receiving treatment.

Highly Oriented Direct-Spun Carbon Nanotube Textiles Aligned by In Situ Radio-Frequency Fields.

Carbon nanotubes (CNTs) individually exhibit exceptional physical properties, surpassing state-of-the-art bulk materials, but are used commercially primarily as additives rather than as a standalone macroscopic product. This limited use of bulk CNT materials results from the inability to harness the superb nanoscale properties of individual CNTs into macroscopic materials. CNT alignment within a textile has been proven as a critical contributor to narrow this gap. Here, we report the development of an altered direct CNT spinning method based on the floating catalyst chemical vapor deposition process, which directly interacts with the self-assembly of the CNT bundles in the gas phase. The setup is designed to apply an AC electric field to continuously align the CNTs in situ during the formation of CNT bundles and subsequent aerogel. A mesoscale CNT model developed to simulate the alignment process has shed light on the need to employ AC rather than DC fields based on a CNT stiffening effect (z-pinch) induced by a Lorentz force. The AC-aligned synthesis enables a means to control CNT bundle diameters, which broadened from 16 to 25 nm. The resulting bulk CNT textiles demonstrated an increase in the specific electrical and tensile properties (up to 90 and 460%, respectively) without modifying the quantity or quality of the CNTs, as verified by thermogravimetric analysis and Raman spectroscopy, respectively. The enhanced properties were correlated to the degree of CNT alignment within the textile as quantified by small-angle X-ray scattering and scanning electron microscopy image analysis. Clear alignment (orientational order parameter = 0.5) was achieved relative to the pristine material (orientational order parameter = 0.19) at applied field intensities in the range of 0.5-1 kV cm-1 at a frequency of 13.56 MHz.

The Dependence of CNT Aerogel Synthesis on Sulfur-driven Catalyst Nucleation Processes and a Critical Catalyst Particle Mass Concentration.

The floating catalyst chemical vapor deposition (FC-CVD) process permits macro-scale assembly of nanoscale materials, enabling continuous production of carbon nanotube (CNT) aerogels. Despite the intensive research in the field, fundamental uncertainties remain regarding how catalyst particle dynamics within the system influence the CNT aerogel formation, thus limiting effective scale-up. While aerogel formation in FC-CVD reactors requires a catalyst (typically iron, Fe) and a promotor (typically sulfur, S), their synergistic roles are not fully understood. This paper presents a paradigm shift in the understanding of the role of S in the process with new experimental studies identifying that S lowers the nucleation barrier of the catalyst nanoparticles. Furthermore, CNT aerogel formation requires a critical threshold of FexCy > 160 mg/m3, but is surprisingly independent of the initial catalyst diameter or number concentration. The robustness of the critical catalyst mass concentration principle is proved further by producing CNTs using alternative catalyst systems; Fe nanoparticles from a plasma spark generator and cobaltocene and nickelocene precursors. This finding provides evidence that low-cost and high throughput CNT aerogel routes may be achieved by decoupled and enhanced catalyst production and control, opening up new possibilities for large-scale CNT synthesis.