bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantification of Hematite and Goethite Concentrations in Kaolin Using Diffuse Reflectance Spectroscopy: A New Approach To Kubelka-Munk Theory
Authors: Gomes Gonçalves Ítalo , Petter Carlos Otávio , Lepkoski Machado Jaqueline 
Published: December 2012

AbstractKaolin ores are usually contaminated by some Fe-bearing minerals, the strong colors of which degrade the quality of the final product. A spectroscopic technique is sought to quantify the content of hematite and goethite, the main contaminant minerals in the kaolin from Capim River in Brazil, was the focus of this study. The total Fe content obtained through X-ray fluorescence showed a poor correlation with the brightness of kaolin, due to the inability to differentiate between the Fe contained in the (oxyhydr)oxides and the Fe present in the crystalline structure of kaolinite, especially when the Fe-bearing minerals occur in small quantities. Here, a new generic technique to quantify Fe (oxyhydr)oxides in kaolin, based on the Kubelka-Munk theory, is presented. A new interpretation of the theory was made that enables its use without the need to measure thin layers of material. The results with synthetic goethite and hematite were very positive (R2pred ≈ 0.99) and experiments with contaminants from the mine are already underway.
Isotope-Dilution Liquid Chromatography–Tandem Mass Spectrometry Candidate Reference Method for Total Testosterone in Human Serum
Authors: Botelho Julianne Cook , Shacklady Christopher , Cooper Hans C , Tai Susan S-C , Uytfanghe Katleen Van , Thienpont Linda M , Vesper Hubert W 
Published: December 2012

BACKGROUNDWe developed and evaluated a candidate reference measurement procedure (RMP) to standardize testosterone measurements, provide highly accurate and precise value assignments for the CDC Hormone Standardization Program, and ensure accurate and comparable results across testing systems and laboratories.METHODSAfter 2 liquid/liquid extractions of serum with a combination of ethyl acetate and hexane, we quantified testosterone by isotope-dilution liquid chromatography–tandem mass spectrometry with electrospray ionization in the positive ion mode monitoring 289→97 m/z (testosterone) and 292→112 m/z (3C13 testosterone). We used calibrator bracketing and gravimetric measurements to give higher specificity and accuracy to serum value assignments. The candidate RMP was evaluated for accuracy by use of NIST-certified reference material SRM971 and validated by split-sample comparison to established RMPs. We evaluated intraassay and interassay imprecision, measurement uncertainty, potential interferences, and matrix effects.RESULTSA weighted Deming regression comparison of the candidate RMP to established RMPs showed agreement with no statistical difference (slope 0.99, 95% CI 0.98–1.00, intercept 0.54, 95% CI −1.24 to 2.32) and a bias of ≤0.3% for NIST SRM971. The candidate RMP gave maximum intraassay, interassay, and total percent CVs of 1.5%, 1.4%, and 1.7% across the concentrations of testosterone typically found in healthy men and women. We tested structural analogs of testosterone and 125 serum samples and found no interferences with the measurement.CONCLUSIONSThis RMP for testosterone can serve as a higher-order standard for measurement traceability and can be used to provide an accuracy base to which routine methods can be compared in the CDC Hormone Standardization Program.
Physicians' Perceived Barriers to Promoting Smoking Cessation
Authors: Berlin Ivan 
Published: December 2012

AbstractBackground/Aims: Physicians' reluctance to promoting smoking cessation reduces the effectiveness of evidence-based recommendations resulting in suboptimal patient outcomes. Primary aim: to draw together findings from studies that addressed physicians' perceived barriers to promoting smoking cessation. Secondary aim: to assess whether interventions for reducing such perceived barriers impact on smoking cessation rates. Methods: Literature search in peer-reviewed journals focused on physicians' perceived barriers to addressing smoking cessation or on intervention studies aimed at alleviating these barriers. Results: The most frequently reported perceived barriers were: time constraints, high workload, lack of training, lack of reimbursement of smoking cessation interventions and the physician's own smoking status. Low outcome expectancy, lack of self-efficacy, fear of losing patients, being uncomfortable to discuss smoking hazards, dissatisfaction with professional activity were also reported. Smoking quit rates of intervention studies aimed to reduce perceived barriers varied according to the barrier targeted. Conclusion: Primary care physicians report a great number of perceived barriers to addressing smoking cessation. Results of intervention studies designed to reduce specific barriers with the purpose of increasing quit rates, remain conflicting. Multilevel intervention studies seem to be needed to assess the efficacy of alleviating perceived barriers to addressing smoking cessation.
The Philippines Waltzes with the Big Boys: Coalition-building Strategy in the WTO
Authors: Quinsaat Sharon Madriaga 
Published: December 2012

Abstract
This article explores the emergence and development of the Philippine coalition-building strategy in the World Trade Organization (WTO) from the Uruguay Round to the Doha Development Agenda. Coalition building is an outcome of social learning, adaptation, and bounded rationality of trade negotiators based on years of working within the norms of the WTO.
Melanocortin 4 receptor distribution in the human hypothalamus
Authors: Siljee Jacqueline E , Unmehopa Unga A , Kalsbeek Andries , Swaab Dick F , Fliers Eric , Alkemade Anneke 
Published: December 2012

ObjectiveThe melanocortin 4 receptor (MC4R) is an essential regulator of energy homeostasis and metabolism, andMC4Rmutations represent the most prevalent monogenetic cause of obesity in humans known to date. Hypothalamic MC4Rs in rodents are well characterized in neuroanatomical and functional terms, but their expression pattern in the human hypothalamus is unknown.Design and methodsTo determine the topographic distribution and identity of cells expressingMC4RmRNA in the human hypothalamus, locked nucleic acidin situhybridization was performed on nine human postmortem hypothalami. In addition, co-expression ofMC4Rwith glial fibrillary acidic protein (GFAP), vasopressin/oxytocin (AVP/OXT), corticotropin-releasing hormone (CRH), neuropeptide Y (NPY), agouti-related protein (AgRP), and α-melanocyte stimulating hormone (α-MSH) was examined.ResultsMost intenseMC4RmRNA expression was present in the paraventricular nucleus (PVN), the supraoptic nucleus (SON), and the nucleus basalis of Meynert. MostMC4R-positive cells in the SON also expressed AVP/OXT. Co-expression with AVP/OXT in the PVN was less abundant. We did not observe co-expression ofMC4RmRNA and GFAP, CRH, NPY, AgRP, or α-MSH. However, fiber-like staining of NPY, AgRP, and α-MSH was found adjacent toMC4R-positive cells in the PVN.ConclusionExpression ofMC4RmRNA in the human hypothalamus is widespread and in close approximation to endogenous MC4R binding partners AgRP and α-MSH.
Prevalence of diabetes mellitus in 6050 hypopituitary patients with adult-onset GH deficiency before GH replacement: a KIMS analysis
Authors: Abs Roger , Mattsson Anders F , Thunander Maria , Verhelst Johan , Góth Miklós I , Wilton Patrick , Kołtowska-Häggström Maria , Luger Anton 
Published: December 2012

ObjectiveGH deficiency (GHD) in adults is characterized by a tendency toward obesity and an adverse body composition with visceral fat deposit and may thus predispose to the development of type 2 diabetes mellitus. The aim of this study was to assess the observed prevalence proportion (PP) and observed PP over expected PP ratio (standardized prevalence proportion ratio, SPR) of diabetes according to International Diabetes Federation criteria in a large cohort of GH-untreated adult-onset GHD patients.Design and methodsAssociations between baseline variables and diabetes prevalence in 6050 GHD patients from KIMS (Pfizer International Metabolic Database) were studied and robust Poisson-regression analyses were performed. Comparisons between baseline status and HbA1c categories in the nondiabetic patients were done with covariance analysis. P values <0.05 were considered statistically significant.ResultsPP was 9.3% compared with the expected 8.2%. SPR was 1.13 (95% confidence intervals (95% CIs), 1.04–1.23), which was significantly increased in females (1.23; 95% CI, 1.09–1.38%) but not in males (SPR 1.04; 95% CI, 0.92–1.17%). PP increased significantly by age, familial diabetes, country selection, BMI, waist circumference, number of pituitary deficiencies, and GHD etiology. SPR decreased significantly by age and increased significantly by BMI, waist circumference, and IGF1 SDS. Multiple regression model showed that the most important impact on SPR was from age and BMI. HbA1c values of 6.0–6.5% were found in 9.5% of nondiabetic patients and were associated with higher BMI and waist circumference.ConclusionsGHD is associated with an increased prevalence of diabetes, largely to be explained by the adverse body composition. These data urge toward early initiation of lifestyle modification measures.
Measurements of Residual Stresses in Low-Stress Silicon Nitride Thin Films Using Micro-Rotating Structures
Authors: Zhang Xin , Zohar Yitshak , Zhang Tong-Yi 
Published: December 2012

AbstractA variety of rotating micro structures were designed, fabricated and characterized for residual-stress (or strain) measurements in low-stress silicon nitride thin films, deposited by LPCVD on silicon wafers. The sensitivities of the micro structures were calculated by finite element method (FEM) and verified experimentally. The results were further confirmed by utilizing the wafer-curvature method for stress measurements. The size of the structures enables local residual-stress (or strain) measurement. The stress level depends on both the film thickness and the gas ratio and also varies with the location on the wafer.
Current Understanding and Modeling of Boron-Interstitial Clusters
Authors: Pichler Peter 
Published: December 2012

AbstractScaling of devices requires not only shallow junctions but also high levels of dopant activation. For boron as the main p-type dopant, the latter requirement is especially problematic since small clusters of boron atoms and self-interstitials, known also as boron-interstitial clusters (BICs), were found to deactivate and immobilize large fractions of the implanted atoms during post-implantation annealing. In this article, the properties of BICs are reviewed and their influence on semiconductor processes are highlighted.
Pulsed Force-Scanning Spreading Resistance Microscopy (PF-SSRM) for High Spatial Resolution 2D-dopant Profiling.
Authors: Eyben P. , Fouchier M. , Albart P. , Charon-Verstappen J. , Vandervorsta W. 
Published: December 2012

AbstractScanning Spreading Resistance Microscopy (SSRM) is now widely used for two-dimensional doping profiling with high spatial resolution. The need for a high force between the tip and the sample in order to obtain a good electrical contact, leads to a fast degradation of the tip (and the sample) while scanning. Tip damage is mainly due to the shear force occurring while scanning in contact mode at high forces leading to breakage (cleavage) of sharp tips or a rapid increase of tip radius (wear). The latter adversely affects the accuracy of the electrical measurements, as the contact radius is a determining parameter for quantification. The strong abrasive force also necessitates the use of tips composed of very hard material such as doped diamond, which has however a limited resistivity, and so far prevented the use of metallic probes. In addition the high force also prevents the simultaneous acquisition of high quality topography data. The solution to these problems is obtained by implementing the Modulated Force Principle (MFP). The latter consists of applying a variable (for instance pulsed) force while scanning, reducing the force during the lateral movement of the tip and synchronizing the electrical measurements with the high force periods. The latter results in lower lateral forces and introduces a quasi multi point contact mode. MFP also allows to obtain a better topography image by synchronizing the topography measurement with the low force part of the force cycle. The MFP leads to a drastic reduction of the surface and probe damage while maintaining high quality electrical data. The implementation of multiplexed detectors within the force cycle further enables the simultaneous acquisition of spreading resistance and topography during one scan, and/or the combination with multiple linear current detectors, capacitance sensors or tunneling current measurements.
Probing the AlxGa1-xN Atomic Distribution via UV-Photoluminescence and Raman at Sub-νm Scale
Authors: Bergman Leah , Chen Xiang-Bai , Householder Tim , McIlroy David , Yeh Wei Jiang , Terrell Stephen , Davis Robert F. 
Published: December 2012

AbstractThe spatial dependence of the band-gap light-emission energy of AlxGa1-xN alloys at composition 0≤ × ≤1 was studied via deep UV-photoluminescence (PL) and Raman microscopy. The data were acquired in a random fashion from an area of ∼ 1mm2 on the sample at steps of ∼1 νm - 200 νm utilizing the 244 nm laser line of probing spot size ∼300 nm radius. Our study indicates that the PL emission energy exhibits random type variations depending on locality: the alloys of composition x=0.12, x=0.22, and x=0.70 exhibit variations of ∼ 10 meV, 30 meV, and 25 meV respectively. The PL of the pure GaN exhibits no spatial dependence while the alloy of x=0.50 exhibits a variation around ∼ 45 meV. Moreover, the functional dependence of the band-gap Eg, on the composition was found to be Eg(x)=3.4(1-x)+6.2x-1.2x(1-x) from which the compositional variation, δx, can be computed for a given variation in the PL emission energy after accounting for the stress effect in the alloys.
Preparation and Characterization of Nanostructured FeS2 and CoS2 for High-Temperature Batteries
Authors: Guidotti Ronald A. , Reinhardt Frederick W. , Dai Jinxiang , Reisner David E. 
Published: December 2012

AbstractIn this paper, we report on the preparation of synthetic FeS2 and CoS2 using a relatively inexpensive aqueous process. This avoids the material and handling difficulties associated with a high-temperature approach. An aqueous approach also allows ready scale-up to a pilot-plant size facility. The FeS2 and CoS2 were characterized with respect to their physical and chemical properties. The synthetic disulfides were incorporated into catholyte mixes for testing in single cells and batteries over a range of temperatures. The results of these tests are presented and compared to the performance of natural FeS2 (pyrite) and a commercial source of CoS2.
High Performance Organic Thin Film Transistors
Authors: Kelley Tommie W. , Muyres Dawn V. , Baude Paul F. , Smith Terry P. , Jones Todd D. 
Published: December 2012

AbstractWe report here methods of surface modification and device construction which consistently result in lab-scale pentacene-based TFTs with mobilities at or above 5 cm2/Vs. Surface modifications include polymeric ultrathin films presenting a passivated interface on which the semiconductor can grow. High performance TFTs have been fabricated on a variety of dielectric materials, both organic and inorganic, and are currently being implemented in manufacturable constructions. Our surface modifications have also proven useful for substituted pentacene materials and for a variety of other organic semiconductors. In addition, we report an all organic active layer, rf-powered integrated circuit. Further experiments and statistical analyses are underway to explain the elevated mobility in our samples, and efforts have been made to confirm these results through collaboration.
Molecular Design, Synthesis and Luminescent Properties of Erbium(III)-Cored Supramolecular Complexes Based on Metalloporphyrins for Optical Amplification
Authors: Oh Jae Buem , Paik Kyung Lim , Ka Jae-Won , Roh Soo-Gyun , Nah Min Kook , Kim Hwan Kyu 
Published: December 2012

AbstractWe have investigated the development of erbium(III)-cored supramolecular complexes containing metalloporphyrins to circumvent the solubility problem and improve the optical amplification property. The new synthetic methodology was accomplished through the ligand-exchange model reaction using ErCl3 to optimize its synthetic condition We have designed and synthesized the model complexes to investigate coordination property between the ligand and the erbium ion. Highly coordinated erbium(III)-cored model complexes (at least 8 to 10 coordination) showed the strong near infrared(IR) emission at 1520 nm, corresponding to the 4I13/2 → 4I15/2 transition. Also, with these synthetic results, erbium(III)-cored supramolecular complexes based on metalloporphyrins were synthesized and characterized. They also showed the infrared emission of the 4I13/2 → 4I15/2 transition at 1520 nm.
Oxidation Of Si / nc-Ge / Si Heterostructures For Non Volatile Memory Applications
Authors: Kanoun M. , Souifi A. , Decossas S. , Dubois C. , Bremond G. , Bassani F. , Lim Y. , Ronda A. , Berbezier I. , Kermarrec O. , Bensahel D. 
Published: December 2012

AbstractIn this work, we present an extensive study of the oxidation process of Si/Ge nanocrystals (nc-Ge)/Si samples using SIMS (Second Ion Mass Spectroscopy), Transmission Electron Micrscopy (TEM), Atomic Force Microscopy (AFM) and electrical characterization of Metal/Oxide/Semiconductor capacitors (MOS). Various samples with different oxidation times have been studied and it is demonstrated that Silicon dry oxidation kinetics is not influenced by the presence of Ge. As shown by SIMS measurements, a pure SiO2 layer is formed on the top of the structure, while the Ge atoms are intermixed with the silicon substrate. The TEM and AFM analysis show that the nc-Ge height is drastically reduced during the oxidation process. The fabrication of MOS capacitors on the structures allowed to study electron and hole trapping in the Ge dots. From our analysis we have shown that the Ge nanostructures which covered by SiO2 are not isolated from the Si substrate.
Structural evolution and acoustic phonon behavior in crystalline PTFE latex films
Authors: Pierno M. , Casari C.S. , Bassi A. Li , Beghi M.G. , Piazza R. , Bottani C.E. 
Published: December 2012

AbstractThe structural evolution of polytetrafluoroethylene (PTFE) crystalline polymer latex films is studied at hundreds nanometer length scale by atomic force microscopy and Brillouin light scattering. In a controlled sintering process the transition is observed from the original particle distribution towards a ‘fibrillar’ structure of crystalline regions embedded in a disordered matrix. This transition is accompanied by a cross-over from localized acoustic excitations to propagating acoustic phonons, related to mesoscopic elastic properties. After sintering, a ‘mark’ of the original particulate structure persists, suggesting that filming of crystalline polymers may be analogous to sintering of ceramic powders. Films of crystalline polymers can thus be exploited as model systems to study the elasto-optical properties of granular and disordered media.
Mechanisms of Low-Temperature Ti/Si-Based Wafer Bonding
Authors: Yu Jian , Wang Yinmin , Haberl Arthur W. , Bakhru Hassa , Lu Jian-Qiang , Gutmann Ronald J. 
Published: December 2012

AbstractThree-dimensional (3D) wafer-level integration is receiving increased attention with various wafer bonding approaches being evaluated. Recently, we explored an alternative lowtemperature Ti/Si-based wafer bonding, in which an oxidized silicon wafer was successfully bonded with a prime silicon wafer at 400°C using 30 nm sputtered Ti as adhesive. The bonded pairs show excellent bonding uniformity and mechanical integrity. Rutherford backscattering spectrometry (RBS) was applied to confirm the interdiffusion occurred in the interlayer. The bonding interface was examined by high-resolution transmission electron microscopy (HRTEM) assisted with electron energy loss spectroscopy (EELS) elemental mapping and energy dispersive X-ray spectroscopy (EDX). Characterization of the bonding interface indicates the strong adhesion achieved is attributed to an amorphous layer formed by interdiffusion of Si and oxygen into Ti interlayer and the unique ability to reduce native oxide (SiO2) by Ti even at low temperatures.
Modeling the Organic Thin Film Transistors
Authors: Olariu Viorel , Rotzoll Robert , Mohapatra Siddharth , Wenz Robert , Grigas Michelle , Dimmler Klaus 
Published: December 2012

AbstractOrganic thin-film transistors (OTFTs) appear to have become strong contenders to silicon based MOSFET devices whenever low-cost and relatively low performance circuits are required in applications such as radio frequency identification (RFID) for large volume supply chains. In order to develop circuits based on OTFTs, circuit designers require circuit models that predict the operation of OTFT with a reasonable accuracy. Although, generally, OTFT operation is similar to ordinary silicon MOSFET devices, there are several characteristics that clearly differentiate them. One important difference between the operation of the OTFT and the silicon MOSFET (that is a direct consequence of the physical implementation of OTFT) is that the organic transistor is normally operated in the accumulation mode, while the silicon transistor regularly operates in the inversion mode. Due to the molecular nature of the semiconductor, the carrier mobility is orders of magnitude lower than for the silicon MOSFET. Variable carrier mobility law, low on/off ratio, and the Schottky barrier at the interface between the source/drain metal contact and the organic semiconductor are among other important effects that had to be considered for developing of an accurate circuit model of the organic transistor. The developed model has been used to simulate DC characteristics and also simple circuits such as logic gates, ring oscillators, rectifiers, etc.This paper presents the developed model as well as a comparison between the simulated data and the experimental data. The experimental circuits were fabricated on flexible plastic substrates and employed a solution-cast dielectric. Pentacene was the semiconductor of choice with carrier mobility in the range of 0.1 – 1.5 cm2/V.s.
Hillock formation and thermal stresses in thin Au films on Si substrates
Authors: Sauter Linda , Balk T. John , Dehm Gerhard , Nucci Julie A. , Arzt Eduard 
Published: December 2012

AbstractThe wafer curvature technique was used to analyze stresses in fine-grained, 50 nm to 2 μm thick Au films on silicon substrates between room temperature and 500°C. The microstructural evolution was analyzed by scanning electron microscopy (SEM), focused ion beam (FIB) microscopy and transmission electron microscopy (TEM). In situ heating experiments inside a scanning electron microscope provided a comparison between the morphological development and the stress-temperature behavior of the film. Hillock formation was observed, but it can only partially account for the stress relaxation measured by the wafer curvature technique.