bluuebunny/crossref_metadata_2025_split huggingface dataset:
Model Misspecification When Excluding Instrumental Variables from PS Models in Settings Where Instruments Modify the Effects of Covariates on Treatment
Authors: Wyss Richard , Ellis Alan R. , Lunt Mark , Brookhart M. Alan , Glynn Robert J. , Stürmer Til 
Published: June 2014

AbstractTheory and simulations show that variables affecting the outcome only through exposure, known as instrumental variables (IVs), should be excluded from propensity score (PS) models. In pharmacoepidemiologic studies based on automated healthcare databases, researchers will sometimes use a single PS model to control for confounding when evaluating the effect of a treatment on multiple outcomes. Because these “full” models are not constructed with a specific outcome in mind, they will usually contain a large number of IVs for any individual study or outcome. If researchers subsequently decide to evaluate a subset of the outcomes in more detail, they can construct reduced “outcome-specific” models that exclude IVs for the particular study. Accurate estimates of PSs that do not condition on IVs, however, can be compromised when simply excluding instruments from the full PS model. This misspecification may have a negligible impact on effect estimates in many settings, but is likely to be more pronounced for situations where instruments modify the effects of covariates on treatment (instrument–confounder interactions). In studies evaluating drugs during early dissemination, the effects of covariates on treatment are likely modified over calendar time and IV–confounder interaction effects on treatment are likely to exist. In these settings, refitting more flexible PS models after excluding IVs and IV–confounder interactions can work well. The authors propose an alternative method based on the concept of marginalization that can be used to remove the negative effects of controlling for IVs and IV–confounder interactions without having to refit the full PS model. This method fits the full PS model, including IVs and IV–confounder interactions, but marginalizes over values of the instruments. Fitting more flexible PS models after excluding IVs or using the full model to marginalize over IVs can prevent model misspecification along with the negative effects of balancing instruments in certain settings.
Estimation of a Predictor’s Importance by Random Forests When There Is Missing Data: RISK Prediction in Liver Surgery using Laboratory Data
Authors: Hapfelmeier Alexander , Hothorn Torsten , Riediger Carina , Ulm Kurt 
Published: June 2014

AbstractIn the last few decades, new developments in liver surgery have led to an expanded applicability and an improved safety. However, liver surgery is still associated with postoperative morbidity and mortality, especially in extended resections. We analyzed a large liver surgery database to investigate whether laboratory parameters like
Overall Effectiveness Factor for Slab Geometry in a Three-Phase Reaction System
Authors: Boldrini Diego E. , Tonetto Gabriela M. , Damiani Daniel E. 
Published: June 2014

AbstractThe overall effectiveness factor for slab geometry applicable to uniform washcoats on a monolith surface for three-phase reaction systems was studied in the present work. Analytical solutions for zero-order reactions and Langmuir–Hinshelwood and power law kinetics were reported. The analysis of the theoretical results showed that not considering the geometry of the monolithic system in a proper way lead to 14% errors in reactions parameters when operating under mixed control (kinetic-internal diffusion) and negligible external mass-transfer resistances.
Wahlkämpfe im Miniaturformat: Fernsehdebatten und ihre Wirkung am Beispiel des TV-Duells 2013 zwischen Angela Merkel und Peer Steinbrück
Authors: Faas Thorsten , Maier Jürgen 
Published: June 2014

AbstractFernsehduelle nach amerikanischem Format gibt es in Deutschland seit 2002, als sich Gerhard Schröder und Edmund Stoiber zu zwei Duellen trafen. In der Zwischenzeit sind solche Duelle zu einem festen Bestandteil von Wahlkämpfen geworden. In dem Beitrag gehen wir der Frage nach, warum die Ereignisse bei den beteiligten Akteuren, den übertragenden Medien, den zuschauenden Bürgerinnen und Bürgern, aber auch der Wissenschaft hohe Wertschätzung genießen. Am Beispiel der Bundestagswahl 2013 zeigen wir schließlich, wie sich diese „Wahlkämpfe im Miniaturformat“ erforschen lassen.
„Anwenderschulung zur computergestützten Informationsbeschaffung für Fortgeschrittene“ oder doch lieber in die Coffee Lectures?
Authors: Renn Oliver 
Published: June 2014

AbstractNutzer empfinden die von wissenschaftlichen Bibliothe­ken angebotenen Schulungen zur Informationskompetenz und insbesondere zu Datenbanken oft als unnötig und uninteressant oder zu zeitraubend. Der Beitrag be­schreibt das Konzept und die ersten Erfahrungen mit den Coffee Lectures, einem Format, welches Ende 2013 an der ETH Zürich eingeführt wurde, und welches auf kurzen, maximal zehnminütigen Vorträgen beruht, während denen gratis ein Kaffee oder Tee getrunken werden kann.
Increased levels of serum γ-glutamyltransferase and uric acid on metabolic, hepatic and kidney parameters in subjects at high altitudes
Authors: Gonzales Gustavo F. , Tapia Vilma 
Published: June 2014

Abstract

Background: Currently there are no studies on γ-glutamyltransferase (γGT) levels at high altitude or on the relationship between γGT, uric acid and several dysfunctions. The aim of the study was to determine the association between serum γGT and uric acid levels in subjects at high altitude with hemoglobin, glycemia, and lipidic, hepatic and kidney markers.

Methods: The present study was performed in 487 subjects aged 30–75 years living at 4100 m of altitude. A venous blood sample was drawn from each subject to measure hemoglobin, glucose, and lipid levels and markers of liver and kidney function. Quartiles for serum γGT and uric acid were calculated and associated with different physiological variables. A p-value <0.05 was considered statistically significant.

Results: Serum γGT values were higher in men (38.35± 2.54 IU/L) than in women (30.33±1.76 IU/L) (p<0.01). Similarly, serum uric acid levels were higher in men (5.78± 0.12 mg/dL) than in women (4.29±0.08 mg/dL; p<0.001). Serum γGT levels in the top quartile were associated with higher glycemia, overweight/obesity, increased levels of non-high-density lipoprotein (non-HDL) cholesterol, triglycerides, alanine aminotransferase, alkaline phosphatase, uric acid, creatinine, and hemoglobin. Levels of uric acid in the top quartile were associated with overweight/obesity, elevated non-HDL cholesterol, triglycerides, creatinine, γGT and hemoglobin. Higher arterial blood pressure was associated with high levels of uric acid but not with γGT levels.

Conclusions: At high altitude, increased γGT levels were associated with hyperglycemia; increased uric acid levels were associated with overweight/obesity, hemoglobin, dyslipidemia, high blood pressure and kidney disease.
Babel and the Fear of Same-Sex Marriage: Mapping Conservative Constellations
Authors: Runions Erin 
Published: June 2014

Abstract
This paper looks at recent allusions to the Babel story as they appear in conservative political and religious discourse to refer to same-sex marriage as a problem of sick egalitarianism and democracy. Liberalism, and a certain kind of democracy, is said to create an imposing and tyrannical neutrality, a neutrality that leads to stagnation and self indulgence, including same-sex relations. This constellation of discourse is explored in relation to the most prominent interpretation of Genesis 11, Josephus’ political retelling in Antiquities of the Jews. Josephus’ version voices fears about tyranny, collectivity, and too much pleasure – themes that are clearly echoed in contemporary references to Babel. The paper shows how the Babel story thus becomes a story about sick egalitarianism associated with same-sex relationships. Tracing this genealogy, the essay argues that such citations of Babel indicate that the fear of gay marriage may actually be a fear of too much democracy.
Energy substrate metabolism in pyruvate dehydrogenase complex deficiency
Authors: Stenlid Maria Halldin , Ahlsson Fredrik , Forslund Anders , von Döbeln Ulrika , Gustafsson Jan 
Published: June 2014

AbstractPyruvate dehydrogenase (PDH) deficiency is an inherited disorder of carbohydrate metabolism, resulting in lactic acidosis and neurological dysfunction. In order to provide energy for the brain, a ketogenic diet has been tried. Both the disorder and the ketogenic therapy may influence energy production. The aim of the study was to assess hepatic glucose production, lipolysis and resting energy expenditure (REE) in an infant, given a ketogenic diet due to neonatal onset of the disease. Lipolysis and glucose production were determined for two consecutive time periods by constant-rate infusions of [1,1,2,3,3-
»Person« und Dreieinigkeit
Authors: Zimmermann Gunter 
Published: June 2014

ZusammenfassungIm ersten Gang der Untersuchung wird gezeigt, dass der Begriff »Person« nicht mit dem Begriff »Mensch« identifiziert werden kann. Aber auch alle Versuche, den Begriff »Mensch« genauer zu fassen und einzugrenzen, führen nicht zu einem adäquaten Verständnis von »Person«. Anhand der Entwicklung des Begriffs in der lateinischen Sprache ist daher zu konstatieren, dass »Person« den Status oder Rang eines handelnden Darstellers kennzeichnet. »Person« ist ein Titel, der mehr oder weniger nach Belieben verliehen werden kann, wobei offensichtlich allein die Handlungsfähigkeit vorausgesetzt werden muss. Unter diesem Gesichtspunkt ist es evident, dass im Lebensdrama jedes Christen der himmlische Vater, der einzige Sohn und der heilige Geist als Personen auftreten. Mit der Formel »tres personae, una persona« kann darüber hinaus auch die Dreieinigkeit insgesamt als Person begriffen werden.
The effects of open holes on the fracture behaviors and mechanical properties of glass fiber mat composites
Authors: Zhang Zhiyuan , Yang Yuqiu , Hamada Hiroyuki 
Published: June 2014

Abstract
In this paper, composite specimens were fabricated from a glass fiber chopped strand mat and unsaturated polyester resin using the hand lay-up method. To evaluate the effects of open holes on the mechanical properties, different factors, including the volume fraction of glass fiber and material thickness were investigated. Both the unnotched strength of smooth specimens and the notched strength of specimens with holes, increased as volume fraction increased, but the trends were different. For notched specimens with closer volume fractions, increased thickness or width-to-depth ratio led to a lower resistance on the open hole. In investigating the fracture behaviors of notched specimens, two different fracture areas were distinguished: parallel areas and fan-shaped areas. The length of each parallel area was measured. To evaluate the material properties, characteristic distance was calculated using linear elastic methods in finite element software (MSC-Marc, MSC Software Corporation, Tokyo, Japan). The results revealed that characteristic distance has a good correspondence with parallel area length.
Measurement of Stiffness Anisotropy in Kaolinite Using Bender Element Tests in A Floating Wall Consolidometer
Authors: Kang X. , Kang G.-C. , Bate B. 
Published: June 2014

Abstract
A new floating wall consolidometer-type bender element testing system was developed to study the stiffness anisotropy of clays at applied vertical stresses up to 800 kPa. One-dimensional slurry-consolidated Georgia RP-2 kaolinite samples, prepared with 0.005 and 1 mol/l NaCl solutions, were tested in this system. A floating wall design eliminated the detrimental bending moment that acts upon the horizontally installed benders as a result of soil settlement in a traditional fixed wall setup, which significantly improved the signal quality and bender reuse. Floating wall–soil interface resistance was quantified with pulling tests. Analytical equations were then derived to calculate the wall resistance-corrected vertical effective stress. As a result, stresses applied to the soil were more accurately determined. The bender element (BE) test was used to measure kaolinite's shear wave velocity (Vs), thereby quantifying the small strain stiffness of soils. Average Vs results for RP-2 kaolinite were lower than those for other kaolinites reported in the literature. This was postulated to be primarily due to the longer and more tortuous chains of particle contacts associated with the smaller median diameter (d50 = 0.36 μm) of RP-2 kaolinite samples. BE test results indicated that Vs increased with stress, density, and concentration. The hierarchy of Vs in three orthogonal directions (i.e., hh &gt; hv &gt; vh) agreed with results in the literature. It was also illustrated that Vs anisotropy increased with applied stress and decreased during unloading. In addition, a comparison was made between the BE test in the new floating wall consolidometer and the BE test in a triaxial testing setup.
Apparent Fracture Toughness Versus Micro-Scale Fracture Toughness of Interfaces—The Challenge of Critical Values
Authors: Kanerva M. , Jokinen J. , Sarlin E. , Saarela O. 
Published: June 2014

AbstractThis study aims to shed light on the conflict between macroscopic fracture toughness and small-scale measures of interface strength when the interface is simulated with an increasing resolution. In the design of practical structures, crack initiation is the critical, limiting phase of material behavior and needs to be defined by lucid means. In this study, we model an example structure, namely a fracture test specimen, including a bi-material interface having micro-roughness and thermal residual stresses. The initiation of secondary cracks, which is one of the microscopic mechanisms leading to crack coalescence, is studied. The work focuses on the effects of the bi-material's Young's modulus, residual stresses, and flaws. The simulation of crack propagation shows that the overall crack tip loading mode mixity distribution is not essentially affected when the Young's modulus of the bi-material's coating is doubled. The analysis of the secondary crack initiation due to interfacial flaws in turn showed that increasing the Young's modulus of either the bi-materials substrate or coating resulted in immediate interface collapse via an elongated ‘damage region’ along the interface.
Human Cancer Xenografts in Outbred Nude Mice Can Be Confounded by Polymorphisms in a Modifier of Tumorigenesis
Authors: Zeineldin Maged , Jensen Derek , Paranjape Smita R , Parelkar Nikhil K , Jokar Iman , Vielhauer George A , Neufeld Kristi L 
Published: June 2014

Abstract
Tumorigenicity studies often employ outbred nude mice, in the absence of direct evidence that this mixed genetic background will negatively affect experimental outcome. Here we show that outbred nude mice carry two different alleles of Pla2g2a, a genetic modifier of intestinal tumorigenesis in mice. Here, we identify previous unreported linked polymorphisms in the promoter, noncoding and coding sequences of Pla2g2a and show that outbred nude mice from different commercial providers are heterogeneous for this polymorphic Pla2g2a allele. This heterogeneity even extends to mice obtained from a single commercial provider, which display mixed Pla2g2a genotypes. Notably, we demonstrated that the polymorphic Pla2g2a allele affects orthotopic xenograft establishment of human colon cancer cells in outbred nude mice. This finding establishes a non-cell-autonomous role for Pla2g2a in suppressing intestinal tumorigenesis. Using in vitro reporter assays and pharmacological inhibitors, we show promoter polymorphisms and nonsense-mediated RNA decay (NMD) as underlying mechanisms that lead to low Pla2g2a mRNA levels in tumor-sensitive mice. Together, this study provides mechanistic insight regarding Pla2g2a polymorphisms and demonstrates a non-cell-autonomous role for Pla2g2a in suppressing tumors. Moreover, our direct demonstration that mixed genetic backgrounds of outbred nude mice can significantly affect baseline tumorigenicity cautions against future use of outbred mice for tumor xenograft studies.
Rate of Spending on Chronic Conditions Among Medicaid and CHIP Recipients
Authors: Agrawal Rishi , Smith Tracie , Li Yan , Cartland Jenifer 
Published: June 2014

OBJECTIVE:
To evaluate the rate at which children with and without chronic conditions became recipients of Medicaid and the Children’s Health Insurance Program (CHIP) during a period of economic recession and to evaluate changes in spending and service utilization among children with chronic conditions.

METHODS:
Child recipients of Illinois fee-for-service Medicaid and CHIP from 2007 to 2010 were assigned to 5 chronic condition groups using 3M Clinical Risk Group software. Outcome measures were change in recipient number in each chronic condition category, total and per capita spending changes within various categories of service, and changes in service utilization.

RESULTS:
From 2007 to 2010, children with chronic conditions became recipients of Illinois fee-for-service Medicaid and CHIP at a higher rate than children without chronic conditions (26.7% vs 14.5%). Inflation-adjusted mean spending fell with a linear trend in all chronic condition categories except malignancy (P &lt; .001). Per member inpatient and emergency department service utilization fell and outpatient service utilization increased in all condition categories. Average inpatient length of stay declined in all chronic condition groups (P &lt; .001) but not in children without chronic conditions.

CONCLUSIONS:
From 2007 to 2010, a period of severe economic recession, a disproportionately high number of children with chronic conditions became Illinois Medicaid and CHIP recipients. Total spending increases were driven by an increase in the number of recipients with the most complex chronic conditions, not increases in per-member spending.
Rotavirus Vaccines and Health Care Utilization for Diarrhea in the United States (2007–2011)
Authors: Leshem Eyal , Moritz Rebecca E. , Curns Aaron T. , Zhou Fangjun , Tate Jacqueline E. , Lopman Benjamin A. , Parashar Umesh D. 
Published: June 2014

OBJECTIVES:
To examine reductions in diarrhea-associated health care utilization after rotavirus vaccine implementation and to assess direct and indirect effectiveness of vaccination.

METHODS:
Retrospective cohort analysis of claims data of commercially insured US children aged &lt;5 years. We examined annual pentavalent (RV5) and monovalent (RV1) rotavirus vaccine coverage. We compared rates of diarrhea-associated health care utilization in prevaccine (2001–2006) versus postvaccine introduction (2007–2011) years, compared rates of diarrhea-associated health care utilization in vaccinated versus unvaccinated children and compared rates in unvaccinated children in postvaccine versus prevaccine years.

RESULTS:
Among children aged &lt;5 years, RV5 and RV1 rotavirus vaccine coverage rates reached 58% and 5%, respectively, by December 31, 2010. Compared with the average rate of rotavirus-coded hospitalizations in 2001–2006, rates were reduced by 75% in 2007–2008, 60% in 2008–2009, 94% in 2009–2010, and 80% in 2010–2011. Compared with unvaccinated children, in 2010–2011, the rate of rotavirus-coded hospitalizations was reduced by 92% among RV5 recipients and 96% among RV1 recipients. Rotavirus-coded hospitalization rate reductions among RV5 recipients versus unvaccinated children ranged from 87% among &lt;1-year-olds to 81% among 4-year-olds. Compared with prevaccine rates in 2001–2006, rotavirus-coded hospitalization rates among unvaccinated children decreased by 50% in 2007–2008, 77% in 2009–2010, and 25% in 2010–2011.

CONCLUSIONS:
Implementation of rotavirus vaccines has substantially reduced diarrhea health care utilization in US children. Both rotavirus vaccines conferred high protection against rotavirus hospitalizations; RV5 conferred durable protection through the fourth year of life. Vaccination also conferred indirect benefits to unvaccinated children.
DESIGN OPTIMIZATION OF A FERROELECTRIC NANO-ACTUATOR USING PHASE-FIELD MODELING
Authors: Balakrishna Ananya Renuka , Huber John E. 
Published: June 2014

ABSTRACTA ferroelectric crystal with charge-free surface conditions contains polarized domains which can form a flux closure with zero net polarization. In the presence of an external electric field, the flux closure in a two-dimensional continuum reorients its spontaneous polarization to align with the field. Based on this concept of ferroelectric switching coupled with mechanical straining, we demonstrate the working principle of a ferroelectric nano-actuator. The behavior of the actuator is explored under the action of electro-mechanical loading and its mechanism is simulated with a 2D phase-field model. The design of nano-actuator is modified to achieve greater actuation displacements by bending a thin device.
Nanostructural tuning of the texture of PZT pervoskite thin films grown by RF sputtering for piezoelectric MEMS
Authors: Mazzalai Andrea , Kratzer Martin , Matloub Ramin , Sandu Cosmin , Muralt Paul 
Published: June 2014

ABSTRACTCurrently, large efforts are going on to scale up PZT thin film processes for large volume MEMS fabrication. It is critical to complete the scaling up with optimized film properties. In this work we report about microstructural control and piezoelectric properties of RF magnetron sputtered PZT (Pb(Zrx,Ti1−x)O3) thin films. The former is a prerequisite to achieve good properties homogeneously on the entire wafer, and with a good repeatability. We focus on the use of a commercial tool capable to reach a deposition rate of 1nm/sec with a thickness uniformity better than +/-3%. We show particularly how the texture can be chosen between (100) and (111) orientation upon tuning the thickness of a very thin TiO2 seed layer on fully passivated Pt electrodes. The surface morphology as resulting from the various grain shapes is strongly influenced by the self-bias established on the substrate, and by the growth temperature. PZT films with compact grain structure and flat surface reached a transverse piezoelectric coefficient e31,f of -23±1 C/m2 in the actuator mode (converse piezoelectric effect) and a dielectric strength of 0.5MV/cm. Both are remarkable values for un-doped, pure PZT thin films.
Embedded Fiber Optic Sensing for Accurate State Estimation in Advanced Battery Management Systems
Authors: Sommer Lars Wilko , Raghavan Ajay , Kiesel Peter , Saha Bhaskar , Staudt Tobias , Lochbaum Alexander , Ganguli Anurag , Bae Chang-Jun , Alamgir Mohamed 
Published: June 2014

ABSTRACTThe problems of using performance parameters such as voltage, current and temperature measured with electrical sensors in today’s battery management systems (BMS) are well known. These parameters can be weakly informative about cell state, particularly as cells age, and contribute to over-conservative utilization and oversizing of a battery pack. Fiber optic (FO) sensors can offer an interesting alternative to conventional electrical sensors, with several advantages such as high selective sensitivity to various parameters, light weight, robustness to EMI, and multiplexing capabilities. In this study, a particular type of FO sensors, fiber Bragg grating (FBG) sensors were externally attached to lithium ion pouch cells for monitoring additional informative cell parameter such as strain and temperature. Multiple charge and discharge cycle were performed to examine the qualification of these signals for cell state estimation in BMS. In comparison to corresponding measurements using conventional electrical sensors, the FBG signals showed very promising results for utilization in effective BMS.