Novel graphene/Sn and graphene/SnO_x hybrid nanostructures: Induced superconductivity and band gaps revealed by scanning probe measurements

Pá,linká,s, Andrá,s,Molná,r, Gyö,rgy,Magda, Gá,bor Zsolt,Hwang, Chanyong,Tapasztó,, Levente,Samuely, Peter,Szabó,, Pavol,Osvá,th, Zoltá,n Elsevier 2017 Carbon Vol.124 No.-

<P>The development of functional composite nanomaterials based on graphene and metal nanoparticles (NPs) is currently the subject of intense research interest. In this study we report the preparation of novel type of graphene/Sn and graphene/SnOx (1 <= x <= 2) hybrid nanostructures and their investigation by scanning probe methods. First, we prepare Sn NPs by evaporating 7-8 nm tin on highly oriented pyrolytic graphite substrates. Graphene/Sn nanostructures are obtained by transferring graphene on top of the tin NPs immediately after evaporation. We show by scanning tunnelling microscopy (STM) and spectroscopy (STS) that tin NPs reduce significantly the environmental p-type doping of graphene. Furthermore, we demonstrate by low-temperature STM and STS measurements that superconductivity is induced in graphene, either directly supported by Sn NPs or suspended between them. Additionally, we prepare SnOx NPs by annealing the evaporated tin at 500 degrees C. STS measurements performed on hybrid graphene/SnOx nanostructures reveal the electronic band gap of SnOx NPs. The results can open new avenues for the fabrication of novel hybrid superconducting nanomaterials with designed structures and morphologies. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Controlling the Slewing Motion of Hydraulically Actuated Cranes Using Sequential Activation of Counterbalance Valves

P°al Andre Nordhammer,Morten Kollerup Bak,Michael Rygaard Hansen 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

This paper is concerned with the controlled motion of hydraulically actuated transmissions characterized by large inertias, backlash and several parallel coupled gearmotors. A method for controlled start and braking of such a transmission is put forward that utilizes sequential activation of the counterbalance valves of the hydraulic circuit. The method, which has been implemented into numerous high end offshore applications, is demonstrated by means of time domain simulations of a knuckle boom crane used for pipe handling in offshore drilling. The suggested activation method may yield higher load levels in the transmission but has the ability to reduce or eliminate the occurence of impact and loss of contact in the transmission.

Relationship Between Psychological Factors and Pain Intensity in Temporomandibular Disorders with or without Central Sensitization: A Cross-Sectional Observational Study Using Multiple Regression Analysis

Pérez Sebastián Eustaquio Martín,Pérez Sebastián Eustaquio Martín,Córdova José Andrés Díaz,Cortés Leidy Milena Posada 대한안면통증∙구강내과학회 2023 Journal of Oral Medicine and Pain Vol.48 No.3

Purpose: To quantify the relationship between perceived pain intensity and psychological variables in a sample of participants with temporomandibular disorder, with or without central sensitization (CS). Methods: A cross-sectional study with nonprobability convenience sampling was conducted from January 1, 2022, to June 30, 2023. Pain intensity (Numeric Pain Rating Scale), anxiety (State-Trait Anxiety Questionnaire, STAI), catastrophizing (Pain Catastrophizing Scale, PCS), perceived stress (Perceived Stress Scale, PSS), and sleep quality (Pittsburgh Sleep Quality Index, PSQI) were assessed. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 20.0 (IBM Co.), which included descriptive and normality analyses and the calculation of strength of multiple correlational regression. Results: A total of 52 (n=34 female 65.4%; n=18 male 34.6%) subjects with diagnosis of temporomandibular disorders (TMD) were finally included. A total of 26 participants (n=26, 50.0%) were cases suffered from CS (TMD-CS mean=46.62±11.24) while the remaining participants (n=26, 50.0%) were the controls (TMD-nCS mean=26.77, standard deviation [SD]=8.42). The pain intensity was moderate in both groups TMDCS (mean=7.62, SD=0.83) and TMD-nCS (mean=7.05, SD=0.86), anxiety (TMD-CS STAI mean=53.27, SD=11.54; TMD-nCS STAI mean=49, SD=11.55), catastrophizing (TMD-CS PCS mean=46.27, SD=9.75; TMD-nCS PCS mean=26.69, SD=4.97), perceived stress (TMDCS PSS mean=30.35, SD=4.91; TMD-nCS PSS mean=26.12, SD=6.60) and sleep quality (TMD-CS PSQI mean=15.81, SD=3.65; TMD-nCS PSQI mean=12.77, SD=2.76) levels were measured in both groups. In TMD-CS and TMD-nCS, higher anxiety levels were moderately and significantly associated with greater pain intensity β=0.4467 (t=2.477, p=0.021) and β=0.5087 (t=2.672, p=0.014). Nevertheless, catastrophizing, perceived stress and sleep quality were not associated to pain intensity in neither of group. Conclusions: In both TMD-CS and TMD-nCS patients, elevated anxiety levels were moderately and significantly associated with increased pain intensity. However, heightened levels of pain catastrophizing, perceived stress, and poor sleep quality were not significantly associated with increased pain intensity in either of the two analyzed groups.

Controversies in the treatment of advanced ovarian cancer in the PARP inhibitors era: a Delphi consensus

Andrés Redondo,Pilar Barretina,Alejandro Pérez-Fidalgo,María Jesús Rubio,Antonio González-Martín 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.5

Objective: Our aim was to reach a consensus on the management of the most controversial issues of advanced ovarian cancer. Methods: Nominal group and Delphi techniques were used. A steering committee of 5 experts analyzed current management of advanced ovarian cancer, identified controversies, critically analyzed the evidence, and formulated guiding statements for clinicians. Subsequently, a panel of 15 experts was selected to test agreement with the statements through two Delphi rounds. Items were scored on a 4-point Likert scale from 1 (totally disagree) to 4 (totally agree). In the first and second rounds, consensus was considered if ≥70% of answers pertained to category 1 or category 4. Results: Overall, 112 statements were incorporated in the following areas: 1) biomarkers and hereditary ovarian cancer; 2) first-line treatment; 3) recurrent disease when platinum might be the best option; and 4) post-poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors setting. In the first Delphi round, 37 statements reached consensus and did thus not pass to the second round. After the second round, another 18 statements reached consensus. Forty-six of the consensus were with the agreement and 9 with the disagreement. Conclusion: Through the methodology used, a consensus was reached in approximately half of the statements. The results of this work may be useful in addressing the most controversial issues on the management of advanced ovarian cancer.

The Constitutive Role of Emotions in the Discursive Construction of the “People”: A Look into Obama’s 2008 “Race Speech”

Carlos Andrés Pérez Hernández 한국외국어대학교 HK 세미오시스 연구센터 2013 Signs and Society Vol.1 No.2

This article examines the semiotic and rhetorical mechanisms by which Obama’s “race speech” builds a mutual identification between Blacks and Whites; it emphasizes the importance of locus communis commonplace and “equivalential links” (Laclau 2005, 94). It also looks at how Obama himself constructs his identity in order to appeal to a racially and politically heterogeneous audience. In addition, it attempts to identify and explain some elements of the speech that may carry heightened emotional content and that may induce a distancing or identification reaction in an audience. From the theoretical standpoint, the article brings to bear the Tartu-Moscow School of Semiotics understanding of metaphor and meaning-generation mechanisms on the Laclauian post-Marxist poststructural concept of the “people,” in order to explain how metaphors participate in the construction of a “people” during a presidential campaign. In terms of cognitive theory, it draws on Lakoff and Johnson’s understanding of metaphorical thinking ([1980] 2003) and Castells’s elaboration on emotions in relation to political cognition (2009). The sociological perspective on emotions aids in the analysis of emotions in social interaction (Turner and Stets 2009). The contribution of this article lies in the semiotic analysis of the role of emotion-evoking elements of the race speech that may indicate a constitutive role in the formation of a “people.”

A Pilot Study of the Spanish Ketogenic Mediterranean Diet: An Effective Therapy for the Metabolic Syndrome

Joaquín Pérez-Guisado,Andrés Muñoz-Serrano 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.7

The “Spanish Ketogenic Mediterranean Diet” (SKMD) has been shown to promote potential therapeutic properties for the metabolic syndrome. The purpose of this study was to evaluate the potential therapeutic properties under free-living conditions of the SKMD in patients with metabolic syndrome (following the International Diabetes Federation consensus guidelines) over a 12-week period. A prospective study was carried out in 22 obese subjects with metabolic syndrome (12 men and 10 women) with the inclusion criteria whose body mass index of 36.58 ± 0.54 kg/㎡ and age was 41.18 ± 2.28 years. Statistical differences between the parameters studied before and after the administration of the SKMD (week 0 and 12, respectively) were analyzed by paired Student's t test. There was an extremely significant (P < .001) improvement in low-density lipoprotein cholesterol (from 126.25 mg/dL to 103.87 mg/dL) and all the parameters studied associated with metabolic syndrome: body weight (from 106.41 kg to 91.95 kg), body mass index (from 36.58 kg/㎡ to 31.69 kg/㎡), waist circumference (from 111.97 cm to 94.70 cm), fasting plasma glucose (from 118.81 mg/dL to 91.86 mg/dL), triacylglycerols (from 224.86 mg/dL to 109.59 mg/dL), high-density lipoprotein cholesterol (from 44.44 to 57.95 mg/dL), systolic blood pressure (from 141.59 mm Hg to 123.64 mm Hg), and diastolic blood pressure (from 89.09 mm Hg to 76.36 mm Hg). The most affected parameter was the triacylglycerols (51.26% reduction). After the diet all the subjects were free of metabolic syndrome according to the International Diabetes Federation definition, and 100% of them had normal triacylglycerols and high-density lipoprotein cholesterol levels, in spite of the fact that 77.27% of them still had a body mass index of >30 kg/㎡. We conclude that the SKMD could be an effective and safe way to cure patients suffering from metabolic syndrome. Future research should include a larger sample size, a longer-term use, and a comparison with other ketogenic diets.

The Effect of the Spanish Ketogenic Mediterranean Diet on Nonalcoholic Fatty Liver Disease: A Pilot Study

Joaquín Pérez-Guisado,Andrés Muñoz-Serrano 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.7

The “Spanish Ketogenic Mediterranean Diet” (SKMD) has been shown to be an effective and safe way to cure patients suffering from metabolic syndrome (MS). Keeping in mind that nonalcoholic fatty liver disease (NAFLD) is closely associated with MS, the purpose of this study was to evaluate the potential therapeutic properties under free living conditions of the SKMD in patients with MS (following the International Diabetes Federation [IDF] consensus guidelines) and NAFLD (suspected by using a cutoff value of alanine aminotransferase [ALT] levels of >40 U/L and confirmed by abdominal ultrasonography) over a 12-week period. A prospective study was carried out in 14 obese men meeting the inclusion criteria and whose body mass index (BMI) and age were 36.58±0.54 kg/㎡ and 41.18±2.28 years, respectively. Statistical differences between the parameters studied before and after administration of the SKMD (week 0 and 12) were analyzed by paired Student's t test (continuous variables) and the χ² test (discontinuous variables). P<.05 was considered statistically significant. There was an extremely significant (P<.001) improvement in body weight (from 109.79 kg to 95.86 kg), low-density lipoprotein-cholesterol (from 123.43 mg/dL to 100.35 mg/dL), ALT (from 71.92 U/L to 37.07 U/L), aspartate aminotransferase (from 47.71 U/L to 29.57 U/L), steatosis degree (complete fatty liver regression was observed in 21.4% of the patients, and an overall reduction was found in 92.86% of the patients), and all the parameters studied associated with the MS: BMI (from 36.99 kg/㎡ to 32.42 kg/㎡), waist circumference (from 114.01 cm to 98.59 cm), fasting plasma glucose (from 118.57 mg/dL to 90.14 mg/dL), triacylglycerols (from 232.64 mg/dL to 111.21 mg/dL), high-density lipoprotein-cholesterol (HDLc) (from 42.81 mg/dL to 58.71 mg/dL), systolic blood pressure (from 142.86 mm Hg to 125.36 mm Hg), and diastolic blood pressure (from 89.64 mm Hg to 77.86 mm Hg). After the diet all the subjects were free of MS according to the IDF definition, and 100% of them had normal triacylglycerols and HDLc levels, in spite of the fact that 100% of them still had a BMI of >30 kg/㎡. We conclude that the SKMD could be an effective and safe way to treat patients suffering from MS and the associated NAFLD.

An efficient method to model the time-domain behavior of viscoelastically damped systems based on an improved fractional derivative model

Erivaldo P. Nunes,Antônio M. G. de Lima,André G. Cunha Filho 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.4

Viscoelastic materials are widely used as an efficient passive control technique to mitigate undesirable vibration and noise in many engineering fields. However, the damping properties of these materials are strongly influenced by operational and environmental factors, such as excitation frequency and operating temperature, leading to some difficulty during the finite element modelling of engineering systems containing these materials, especially for transient analysis. Thus, it is proposed herein an improved fractional derivative model to be combined with the finite element method in a straightforward way to describe the frequency- and temperature-dependent behavior of viscoelastic materials. As an academic application, the influence of the temperature on the transient responses of a viscoelastic sandwich beam subjected to some types of excitations is addressed. Moreover, the parameters of the viscoelastic model are obtained by curve-fitting for each operating temperature and the resulting equations of motion of the viscoelastic system in the time-domain are solved by using the Newmark integration scheme. Through this improved fractional derivative model, the time-domain responses of the viscoelastic sandwich beam are evaluated for several operating temperatures and compared with the corresponding obtained by the open literature to demonstrate the main features and capabilities of the proposed method.

Characterization and Properties of Ethylene-Propylene Copolymers Synthesized with Homogeneous and Supported Metallocene Catalyst in the Whole Range of Compositions

Javier Arranz-Andrés,Inmaculada Suárez,Rosario Benavente,Ernesto Pérez 한국고분자학회 2011 Macromolecular Research Vol.19 No.4

Two series of ethylene-propylene copolymers were synthesized in the whole composition range using a metallocene catalyst, one in the homogeneous phase (H copolymers), and the other with the catalyst supported in silica (S copolymers). Some differences were found between the two groups. Therefore, the amount of ethylene needed to obtain a certain proportion of the γ form is lower in the H than in S series. Moreover, the composition to obtain the pseudo hexagonal form is also different for the two groups. On the other hand, degree of crystallinity, crystal sizes and microhardness values display a similar variations with the comonomer content of the two series. Consequently, from a macroscopic point of view, materials with similar macroscopic mechanical properties can be produced using both supported and homogeneous metallocene catalysts despite the structural differences.

Transmission Fiber Chromatic Dispersion Dependence on Temperature: Implications on 40 Gb/s Performance

Paulo S. André,Ant?io L. Teixeira,Armando N. Pinto,Lara P. Pellegrino,Berta B. Neto,J?e F Rocha,Jo? L. Pinto,Paulo N. Monteiro 한국전자통신연구원 2006 ETRI Journal Vol.28 No.2

In this letter, we will evaluate the performance degradation of a 40 km high-speed (40 Gb/s) optical system, induced by optical fiber variations of the chromatic dispersion induced by temperature changes. The chromatic dispersion temperature sensitivity will be estimated based on the signal quality parameters.