cssi/SciSciGPT-SciSciNet huggingface dataset:
Timing and Risk Factors Associated With Postoperative Stroke in Vascular Surgery Patients Using Time-Varying Coefficients From a Cox Model

BACKGROUND Mechanisms of postoperative stroke are poorly understood, particularly for strokes occurring after uneventful emergence from anesthesia. We sought to create a model to study retrospectively the timing and associations for stroke in a high-risk surgery population. METHODS Using a large prospective database containing detailed information on the occurrence and timing of stroke, we identified patients undergoing procedures involving the distal vascular (DV) and the cerebral vascular (CV) to assess the association between perioperative factors and stroke. We used separate Cox regressions with time-varying coefficients, one for each cohort, to assess the association between baseline factors and the timing of postoperative stroke within the DV and CV cohorts. Using time-varying coefficients allows hazard ratios to vary over time rather than assuming that the hazard ratio remains constant with time. Propensity score matching was used to compare the timing of stroke between DV and CV groups. RESULTS Among the 80,185 patients with qualifying procedures, there were 711 strokes (0.9%) in the first 30 days after surgery. Stroke incidence was lower for DV patients (0.5%, 306/57,553; P < .001) than CV (1.8%, 405/21,940) and the majority of strokes in the DV group were delayed, occurring between postoperative (POD) days 2 and 30 (236/306, 77%). Among the 711 patients who had a stroke, the proportion of strokes that occurred on day 0 was 8% (n = 24 of 306 strokes) in the DV group compared to 35% in the CV group (n = 140 of 405 strokes). Factors associated with stroke on POD 1 for both groups were preoperative mechanical ventilation and emergent procedures. Acute renal failure and female sex were highly associated with delayed stroke (POD 2-30). Perioperative blood transfusion was associated with an increased hazard of delayed stroke in the DV group and a hazard ratio that increased with time in the CV group. CONCLUSIONS After adjusting for confounding, stroke was more common and occurred earlier in the CV group. Factors associated with delayed postoperative stroke include acute renal failure, emergent procedures, female sex, preoperative mechanical ventilation, and perioperative transfusion.
Embracing Crimmigration to Curtail Immigration Detention

Immigration advocates have long objected to both the constitutionality and the conditions of immigration detention. However, legal challenges to the practice have been largely unsuccessful due to immigration law’s “exceptionality.” Placing recent litigation carried out against immigration detention in the midst of the COVID-19 pandemic within the context of the judiciary’s approach to immigration, I argue that litigation is an extremely limited strategic avenue to curtail the use of immigration detention. I then argue that anti-immigration detention advocates should attempt to incorporate their agenda into criminal legal reform and decarceration efforts. This is important for both movements. Normatively, immigration detention raises comparable concerns: Namely, that jailing people is, on the one hand an extreme and cost-ineffective form of social control, and on the other, a tool to marginalize or “otherize” entire communities. Furthermore, there is evidence that ongoing efforts to decarcerate states and localities may be foiled by immigration detention. To the extent, therefore, that decarceration is based on commitments to freedom or condemnation of the extensive use of carceral institutions, they are incomplete and even dangerous without including measures to address immigration detention. Immigration advocates, on the other hand, are more likely to succeed by placing the anti-immigration detention agenda within the scope of larger criminal legal reform than by pursuing either immigration detention reform or anti-detention litigation.
Direct Current Ablation of Deep Substrate Arrhythmia.

Abstract Direct-current ablation has been reinvestigated in animal models with considerably good outcomes and safety margins. Its modified version using biphasic energy lowers the current density f...
The Center for Regional and Tribal Child Welfare Studies: Systems change through a relational Anishinaabe worldview

Abstract The dramatic overrepresentation of Indigenous families in North American governmental child welfare systems remains one of the most pressing and neglected issues facing Tribal Nations, child welfare policymakers and practitioners today. This paper is the third in a series of three papers (Authors) presenting an ethnographic study of the Center for Regional and Tribal Child Welfare Studies in the Department of Social Work, University of Minnesota – Duluth. The current paper focuses on the perspectives of the Center’s staff and allies, which is grounded in an Anishinaabe worldview, on the process of systems change in child welfare. It draws upon in-depth, semi-structured interviews with 13 participants with diverse roles and extended relationships with the Center. Participants provided knowledge and wisdom on how to create and sustain trusting, collaborative relationships within sovereign Tribal Nations, county and state child welfare systems. They described how Center staff members are then able to create bridges (mesosystems) across Indigenous communities and child welfare systems with the trust built within each of those systems. These mesosystems are sustained over time through continued opportunities for engagement and collaboration. These processes are illustrated through several case exemplars of change affected by the Center, tribes and their collaborators: state legislation to strengthen ICWA, implementation of statewide continuing education for child welfare professionals, and an innovative ICWA court. The primary barrier to system change noted by participants is structural racism. Advice for those motivated to support systems change includes establishing close links with Indigenous communities.
Lymphoid Interstitial Pneumonia and Follicular Bronchiolitis

Follicular bronchiolitis (FB) and lymphoid interstitial pneumonia (LIP) are a continuum of benign infiltration of the lungs by polyclonal mature lymphocytes. Rarely idiopathic, LIP and FB may represent an expression of systemic immunologic disorders in the lung and are commonly associated with immunodeficiencies, connective tissue diseases, and other autoimmune conditions. This chapter reviews the clinical, radiologic, and pathologic presentation of both entities in this continuum.
The uneven distribution of fees for virtual academic conferences

This study examines factors of importance for the pricing of virtual academic conferences based on information on their quality attributes. Data are based on 76 virtual conferences held or planned ...
Widespread prevalence of hypoxia and the classification of hypoxic conditions in the Laurentian Great Lakes

Abstract Aquatic hypoxia within the Laurentian Great Lakes has contributed to various adverse ecological consequences and stimulated research interest in recent decades. An analysis of published peer-reviewed journal articles from 2000 to 2020 demonstrates an increasing trend of studies related to hypoxia in the Laurentian Great Lakes. However, the majority of these studies (78%) focus on Lake Erie and in particular the well-documented hypolimnetic hypoxic conditions that develop in the central basin of Lake Erie. This hypoxic zone is relatively large (up to 1.5 million ha), has substantial ecological effects, and motivates monitoring programs and water quality improvement initiatives. Nonetheless, the hypoxic zone in the central basin of Lake Erie is only one of over twenty documented hypoxic zones in the Laurentian Great Lakes. Moreover, hypoxic conditions in the Great Lakes are quite diverse. Here, we define and characterize a four-fold classification of Great Lakes hypoxic conditions: 1) hypolimnetic hypoxia, 2) over-winter hypoxia, 3) diel hypoxia, and 4) episodic hypoxia. We suggest that Great Lakes research and monitoring programs should seek to more broadly document hypoxic conditions and develop models to predict the temporal and spatial occurrence of hypoxia. Such efforts are particularly timely as future climatic conditions contributing to warmer temperatures, longer and more intense stratified periods, increased spring nutrient loading and more variable allocthonous inputs are expected to exacerbate three of the four hypoxic conditions described for the Great Lakes (hypolimnetic, diel, and episodic hypoxia).
Turks Across Empires: Marketing Muslim Identity in the Russian-Ottoman Borderlands, 1856-1914

I read with interest Dr Azade-Ayse Rorlich’s (2016) review of my book, Turks Across Empires: Marketing Muslim Identity in the Russian–Ottoman Borderlands, 1856–1914 (Oxford University Press, 2014)....
Gauge-invariant implementation of the Abelian-Higgs model on optical lattices

We present a gauge-invariant effective action for the Abelian-Higgs model (scalar electrodynamics) with a chemical potential $\ensuremath{\mu}$ on a ($1+1$)-dimensional lattice. This formulation provides an expansion in the hopping parameter $\ensuremath{\kappa}$ which we test with Monte Carlo simulations for a broad range of the inverse gauge coupling ${\ensuremath{\beta}}_{pl}=1/{g}^{2}$ and small values of the scalar self-coupling $\ensuremath{\lambda}$. In the opposite limit of infinitely large $\ensuremath{\lambda}$, the partition function can be written as a traced product of local tensors which allows us to write exact blocking formulas. Gauss's law is automatically satisfied and the introduction of $\ensuremath{\mu}$ has consequences only if we have an external electric field, ${g}^{2}=0$ or an explicit gauge symmetry breaking. The time-continuum limit of the blocked transfer matrix can be obtained numerically and, for ${g}^{2}=0$ and a spin-1 truncation, the small volume energy spectrum is identical to the low energy spectrum of a two-species Bose-Hubbard model in the limit of large on-site repulsion. We extend this procedure for finite ${\ensuremath{\beta}}_{pl}$ and derive a spin-1 approximation of the Hamiltonian. It involves new terms corresponding to transitions among the two species in the Bose-Hubbard model. We propose an optical lattice implementation involving a ladder structure.
Alternative ansatz to wounded nucleon and binary collision scaling in high-energy nuclear collisions

We introduce a new parametric initial-condition model for high-energy nuclear collisions based on eikonal entropy deposition via a ``reduced-thickness'' function. The model simultaneously describes experimental proton-proton, proton-nucleus, and nucleus-nucleus multiplicity distributions and generates nucleus-nucleus eccentricity harmonics consistent with experimental flow constraints. In addition, the model is compatible with ultracentral uranium-uranium data unlike existing models that include binary collision terms.
Type I Interferon Signaling in Shaping Cellular Innate and Adaptive Immunity to Viral Infection

The best-studied cytokines in terms of the understanding of their signaling for immunoregulatory effects on innate and adaptive immunity during viral infections are the type I interferons (IFNs), and certain viruses appear to preferentially induce the innate factors to high and sustained levels. Natural killer (NK)-cell cytotoxicity may also have other downstream immunoregulatory functions because viral infections can trigger profound diseases characterized by hyperactivation of macrophages and cytokine production, such as hemophagocytic lymphohistiocytosis, in mice and men with defects in the molecular mechanisms required for delivery of killing function. The cytokines help support the accumulation of plasmacytoid dendritic cells (pDCs), major contributors to type I IFN production during certain viral infections. In addition, they have effects on other DC populations thought to be important in mediating antigen-presenting cell functions for the activation of adaptive immunity, although some of these are paradoxical. Thus, type I IFNs produced during early viral infections link the immediate earliest responses to induction of innate defense mechanisms delivered by NK cells and shape the DC responses for type I IFN production and induction of adaptive immunity. To evaluate the consequences of different Stat levels on cellular responses to type I IFNs and on the endogenous immune responses to viral infections, experiments have been carried out in uninfected and lymphocytic choriomeningitis virus (LCMV)-infected immunocompetent mice and mice deficient in Stat1 or Stat2. Type I IFNs are currently being used in the treatment of chronic infections with hepatitis C virus, cancers, and multiple sclerosis.
Mobility management application protocol (MMAP) for North American PCS networks

The task of North American personal communication services (PCS) standards has been undertaken by two organizations, i.e. Committee T1 sponsored by the Alliance for Telecommunications Industry Solutions (ATIS) and the Telecommunications Industry Association (TIA) Engineering Committee TR45. Traditionally; Committee T1 has been the major force behind the development of the North American wireline standards whereas TR45's focus has been the wireless information networks and mobility management. Another TIA Committee, TR46, was also involved with defining standard interfaces for PCS networks. Subcommittee T1S1 established the mobility management application protocol (MMAP) subworking group in 1994 to produce a stage 3 protocol for supporting the mobility management requirements of the radio access systems defined by the Joint Technical Committee (JTC) of T1 and TIA. T1S1 MMAP SWG issued the first version of the standard in June 1995 and ballot comments were resolved in September 1995. The standard, T1.651-1996, includes operations defined between the service control function (SCF) and the radio access control function (RACF) as well as the interface between RACFs. The second phase, which has already started, addresses the interface between the RACF and the radio control function (RCF) as well as additional operations for the SCF-RACF and RACF-RACF interfaces.
The Handbook of Geographic Information Science, edited by J.P. Wilson and A.S. Fotheringham

Contrasting with the recent influx of encyclopedic GIScience books, the Handbook of Geographic Information Science edited by John Wilson and Stewart Fotheringham (published in Oxford, UK, by Blackw...
Managing Externalities in Multi-Unit Housing

Abstract In this paper, we examine some of the ways that the market responds to housing externalities, focusing especially on multi-unit, low income housing. We develop a theoretical model of a household’s choice among private rental housing, public housing, and limited equity cooperative housing. The results suggest that the ability of LECs to attract tenants depends, among other things, on the ability of self-management to internalize housing externalities compared to hierarchical management. Case studies of LECs suggest that the results are mixed.
SMODELS A : a system for computing answer sets of logic programs with aggregates

In [2], we presented a system called - for computing answer sets of logic programs with aggregates. The implementation of - relies on the use of an external constraint solver (ECLiPSe) to deal with aggregate literals and requires some modifications to the answer set solver used in the experiment (Smodels). In general, the system is capable of computing answer sets of arbitrary programs with aggregates, i.e., there is no syntactical restrictions imposed on the inputs to the system. This makes - different from dlvA (built BEN/5/23/04) [1], which deals with stratified programs only. - , however, is based on a semantics that does not guarantee minimality of answer sets. Furthermore, our experiments with - indicate that the cost of communication between the constraint solver and the answer set solver proves to be significant in large instances.
A Simple Computational Form for Maxwellian Reactivities

A simple form is given for the evaluation of Maxwellian reactivities for the reactions T(d,n)4He, D(d,p)T, D(d,n)3He, and 3He(d,p)4He, with applications to the analytical treatment of fusion reacto...
13 Alternative electrofocusing methods

Publisher Summary The chapter discusses alternative electrofocusing methods. Isoelectric focusing (IEF) is influenced less by length, therefore, alternative electrofocusing methods (AFMs), which do not focus solutes at their isoelectric points (pI), may allow scientists to circumvent this limitation. The AFMs analyzed in this chapter are part of a subset of the equilibrium gradient methods (EGMs) that use an applied electric field or electric field gradient as at least one of the counterbalanced forces on a focused solute. A complete binary set of EGMs would consist of dozens of pairs of forces, some of which are mentioned in the context of field-flow fractionation (FFF) as well as myriad variations on isocratic and gradient–elution chromatographies, each paired against a second force, for example, hydrodynamic. The chapter discusses the emerging set of methods in the hope that “gadgeteers” and theorists will explore this frontier and help scientists develop new tools for systems biology. The use of the word “equilibrium” in EGM is not warranted, because these systems are actually either in a steady state or a pseudosteady state—that is, when the peak is moving but not changing shape. The chapter presents a figure of the most important instance of field–gradient electrofocusing of counter-acting chromatographic electrophoresis (CACE). To understand the underlying principles involved in the AFMs, the component of the mass flux equation that is parallel to the electric field is needed to be considered. According to linear theory, electric field–gradient focusing (EFGF) will provide a resolution and peak capacity that is roughly intermediate between those predicted for narrow- and broad-range ampholytes.
Induction of psychogenic nonepileptic events: success rate influenced by prior induction exposure, ictal semiology, and psychological profiles.

Summary Purpose: To evaluate whether certain preinduction clinical characteristics may influence the success rate of induction. Methods: We prospectively enrolled and attempted inductions on 51 patients who were suspected to have psychogenic nonepileptic events based on clinical grounds. In addition to careful examination of the reported ictal semiology, we administered a battery of four psychological instruments to our enrolled patients. Key Findings: We found that among 42 cases of successful induction, 92.9% (n = 39) of these cases were successfully induced on the first attempt (i.e., without prior induction exposure). We observed that induction showed significantly higher rate of success in cases that demonstrate: (1) hypermotor ictal semiology (p = 0.029); (2) more prevalent self-reporting of uncommon cognitive and affective symptoms (p = 0.035); or (3) higher tendency to rely on coping strategies of “instrumental support” (p = 0.013) and “active coping” (p = 0.027), when compared to noninducible cases. Significance: Singular administration of placebo induction on preselected patients with these clinical characteristics may reduce costs by shortening video electroencephalography–(EEG) monitoring sessions and improve the diagnostic yield of video-EEG even for patients with very infrequent events.
Metabolic regulation of T cell differentiation and function

Upon encountering pathogens, T cells mount immune responses by proliferating, increasing cellular mass and differentiating. These cellular changes impose significant energetic challenges on T cells. It was believed that TCR and cytokine-mediated signaling are dominant dictators of T cell-mediated immune responses. Recently, it was recognized that T cells utilize metabolic transporters and metabolic sensors that allow them to rapidly respond to nutrient-limiting inflammatory environments. Metabolic sensors allow T cells to find a balance between energy consumption (anabolic metabolism) and production (catabolic metabolism) in order to mount effective immune responses. Also, metabolic regulators interact with cytokine-dependent transcriptional regulators, suggesting a more integrative and advanced model of T cell activation and differentiation. In this review, we will discuss recent discoveries regarding the roles of metabolic regulators in effector and memory T cell development and their interaction with canonical transcription factors.
The role of risk and return in information technology outsourcing decisions

This paper views information technology (IT) outsourcing decisions as classical make-or-buy decisions. In essence, these decisions consist of finding an acceptable balance between benefits and risks. The principal contribution of this paper is the development of a model that describes the relationship between outsourcing benefits and risks. It draws on work from two streams of research: transaction cost theory and modern financial theory. The model can assist managers in determining whether outsourcing or insourcing is a better choice for a particular IT function and in evaluating and comparing competing vendor proposals. The model can also serve as a framework for future research in IT governance issues.
Synergistic use of Landsat Multispectral Scanner with GIRAS land-cover data to retrieve impervious surface area for the Potomac River Basin in 1975

Abstract For many studies of urbanization, particularly those covering broad spatial extents and thus requiring the perspective afforded by satellite remote sensing, the longest time series of impervious surface area (ISA) initiate with the availability of Landsat Thematic Mapper (TM) data in the mid 1980s. Earlier generation remote sensing data, such as Landsat Multispectral Scanner (MSS) do not generally lead to robust representations of impervious surface area due to poor spectral differentiation between impervious and non-impervious surfaces lacking vegetation. In the 1970s, however, the USGS completed a comprehensive mapping of land cover based on aerial photography called the Geographic Information Retrieval and Analysis System (GIRAS). In this paper we describe a methodology for retrieving ISA estimates through the fusion of GIRAS land cover with historic and contemporary remote sensing data, resulting in a data set that is temporally comparable to more modern data sets (e.g. the National Land Cover Database (NLCD) ISA product). We calculate correlation coefficients between our data set and digitized aerial photography at 4 spatial resolutions, exhibiting a maximum correlation of 0.65 at 120-m and 240-m pixel sizes. Our highest resolution product (30-m) exhibited 94% accuracy and a kappa coefficient of 36% in rural areas, and 90.7% accuracy and a kappa coefficient of 59.6% in suburban areas. Further, we show that trends in urban area through time derived from these data exhibit accelerating rates of development throughout the Potomac River basin 1975–2001, including increased development in riparian buffer zones and on steeper topography. These results are applicable wherever low-resolution vector-based data sets of urban area are available or could be generated for the pre-Landsat TM era.
Photogeneration of Superoxide Anion in Serum of Bovine Milk and in Model Systems Containing Riboflavin and Amino Acids

Abstract Superoxide anion was generated in the serum of bovine milk following illumination with fluorescent light. This was shown by suppression of nitro blue tetrazolium reduction by superoxide dismutase. The production of superoxide anion was not evident in dialyzed milk serum, but addition of 3.2 µM of riboflavin to the dialyzed serum restored its production to about 50% that of the undialyzed serum. Apparently, serum components of both low and high molecular weight served as oxidizable substrates to photoreduce riboflavin which in turn reduced oxygen to superoxide anion. A model system equivalent in pH and riboflavin concentration to milk was used to evaluate low molecular weight compounds in milk serum for their ability to photogenerate superoxide anion. Of the compounds tested, only orotic acid formed any of it when tested at concentrations typical of milk. Among twenty three amino acids evaluated, only cysteine, methionine, his-tidine, tyrosine, and tryptophan supported superoxide anion photogeneration. The initial rate of photogeneration for the cysteine-riboflavin system was four times greater than for the other amino acids sensitive to oxidation. Blocking the carboxyl group of methionine reduced production of superoxide anion by more than 50% whereas blocking the amino group had a negligible effect. Changing the pH of model methionine-riboflavin systems from 6.7 to 4.5 drastically decreased the production of superoxide anion. Flavin mononucleotide, flavin adenine, dinucleotide, and xanthine oxidase in the presence of methionine were 77, 26, and 4% as effective as riboflavin, on an equivalent riboflavin basis, in generating superoxide anion. Native ribonuclease yielded small quantities of it upon illumination in the presence of riboflavin, but generation increased about 15 fold upon reduction of the ribonuclease. Reoxidation of the reduced ribonuclease resulted in a return of superoxide anion production similar to that of the native ribonuclease.
A comparison of active vibration control techniques - Output feedback vs optimal control

The paper presents analytical and experimental comparison of two control laws for a laboratory structure designed to simulate large space structures. The first control law is the standard linear quadratic law, which is optimal but requires model reduction for practical implementation. The second control law is a new simple direct feedback control law designed to minimize control forces while guaranteeing stability. The optimal control law was found to be only slightly better than the direct feedback law even in terms of the quadratic performance index. Moreover, the optimal control law provided almost no margin of stability for the unmodeled modes while the direct feedback law provided significant stability margins to all modes. The above results were verified experimentally using a digital implementation of the control laws. Excellent agreement between the analytical prediction and experimental measurements was observed.
Structural determinants of household art expenditure

Purpose – The purpose of this paper is to empirically investigate the influences of sociodemographic (SD), environmental, and marketing mix variables on household art expenditure.Design/methodology/approach – Using the latest US census data collect from 140 metropolitan statistical areas, three stepwise multiple regressions are employed to identify the key determinants of household art expenditure and their directional impacts.Findings – The paper evinces that a set of SD, environmental, and marketing mix variables explains a large percentage of variation of household art expenditure. In addition to that, these variables influence household art expenditure differently.Research limitations/implications – Limited by data availability, this paper focuses on investigating the effects of variables with available measures. Future researchers are encouraged to include a broader range of variables in analysis whenever possible.Practical implications – This paper suggests that art dealers use the approach adopted ...
Generalized Sylvester theorems for periodic applications in matrix optics

Sylvester’s theorem is often applied to problems involving light propagation through periodic optical systems represented by unimodular 2 × 2 transfer matrices. We extend this theorem to apply to broader classes of optics-related matrices. These matrices may be 2 × 2 or take on an important augmented 3 × 3 form. The results, which are summarized in tabular form, are useful for the analysis and the synthesis of a variety of optical systems, such as those that contain periodic distributed-feedback lasers, lossy birefringent filters, periodic pulse compressors, and misaligned lenses and mirrors. The results are also applicable to other types of system such as periodic electric circuits with intracavity independent sources, high-energy particle accelerators, and periodic computer graphics manipulations that may include object translation. As an example, we use the 3 × 3 form of Sylvester’s theorem to examine Gaussian beam propagation in a misaligned resonator.
The self-induced motion of vortex sheets

A method is presented for following the self-induced motion of vortex sheets. In this method, we use a piecewise analytic representation of the sheet consisting of circular arcs with trigonometric polynomials for the circulation. The procedure is used to study the evolution of the motion in two special cases: a circular vortex sheet with sinusoidal circulation distribution and an infinite plane vortex sheet subject to periodic disturbances. The first problem was studied by Baker (1980) as a test of the method of Fink & Soh (1978), while the second has been studied by a number of authors, notably Meiron, Baker & Orszag (1982). In each case, we follow the motion of the sheet up to the appearance of a singularity at a finite time. The singularity takes the form of an exponential spiral with the simultaneous development of singularities in the curvature and in the circulation distribution. In the final stages of the calculations, up to 155 marker points are used to specify the position of the sheet. If it were possible to execute a stable calculation with equally spaced point vortices, approximately 106 points would be required to achieve the same resolution. Problems with instabilities have been reduced, but not entirely eliminated, and prevent a rigorous verification of the results obtained.
Generating planar 4-connected graphs

In this paper, we introduce three operations on planar graphs that we call face splitting, double face splitting, and subdivision of hexagons. We show that the duals of the planar 4-connected graphs can be generated from the graph of the cube by these three operations. That is, given any graphG that is the dual of a planar 4-connected graph, there is a sequence of duals of planar 4-connected graphsG 0,G 1, …,G n such thatG 0 is the graph of the cube,G n=G, and each graph is obtained from its predecessor by one of our three operations.
A Raman spectroelectrochemical study of potential-controlled benzenethiol desorption from Pt–Fe group alloy films

Abstract A combination of in situ Raman spectroelectrochemistry and cyclic voltammetric (CV) stripping methods is used to study the adsorption/desorption of benzenethiol (BT) at platinum (Pt) alloy electrodes. The data from both methods confirm that alloying Pt with Fe group metals enhances the sulfur tolerance of the alloy over Pt. The Raman signal of BT adsorbed at electrodeposited films of Pt 3 Co and Pt 4 Ni diminishes to a greater extent after only one oxidation/reduction cycle than that observed for BT adsorbed at pure Pt films. Oxidatively desorbed BT readsorbs at Pt 3 Co at a potential that is ∼50 mV lower than that at which it readsorbs at either Pt or Pt 4 Ni films, further demonstrating its enhanced sulfur tolerance. Sulfate bands are absent from the spectra of all films, indicating that the metal–S bonds that form upon adsorption are broken during oxidative removal of BT rather than cleavage of C–S bonds in the BT adsorbate. The CV stripping data confirm that BT is more readily electrochemically stripped from the alloy films than from pure Pt films. The combination of Raman spectroelectrochemistry and CV stripping enables more comprehensive characterization of sulfur-tolerant electrocatalyst surfaces in situ , under electrochemical conditions.
Therapeutic approaches to postoperative ischemia

Abstract Previous attempts to identify predictors of cardiac complications, an important cause of postoperative morbidity and mortality following noncardiac surgery, have focused mainly on the patient's preoperative state. Our research group, however, has found that adverse cardiac outcome correlates most highly with the appearance of at least 1 ischemic episode determined by continuous ambulatory electrocardiographic monitoring (AEM) in the early postoperative period. Such early postoperative ischemia conferred (1) a greater than 9-fold increased risk of experiencing in-hospital cardiac death, nonfatal myocardial infarction, or postoperative unstable angina, and (2) a greater than 2-fold increased long-term (2-year) risk of cardiac death, myocardial infarction, or angina requiring coronary angioplasty or coronary artery bypass grafting (CABG). Additionally, 5 predictors of such postoperative ischemia were identified: left ventricular hypertrophy, diabetes mellitus, hypertension, definite coronary artery disease, and preoperative digoxin use. These findings suggest that patients who are at high risk for postoperative myocardial ischemia warrant more intensive postoperative monitoring. Moreover, since such ischemia is potentially reversible, the testing of strategies designed to prevent or manage postoperative ischemia appears warranted and is discussed. Our group also has established the usefulness of AEM for identifying ischemic episodes in patients undergoing CABG. However, patients who require cardiopulmonary bypass present unique problems regarding the interpretation of AEM recordings. We describe guidelines for the interpretation of AEM results obtained under these conditions and suggest criteria based on the degree of interpretability for patient inclusion in future studies.
Competition between Line Tension and Curvature Stabilizes Modulated Phase Patterns on the Surface of Giant Unilamellar Vesicles. a Simulation Study

When prepared in the liquid-liquid coexistence region, the four-component lipid system distearoyl-phospha-tidylcholine--dioleoyl-phosphatidylcholine--palmitoyl,oleoyl-phosphatidylcholine--cholesterol (DSPC-DOPC-POPC-Cholesterol), with certain ratios of DOPC and POPC, shows striking modulated phase patterns on the surface of giant unilamellar vesicles (GUVs). In this simulation study, we show that the morphology of these patterns can be explained by the competition of line tension (which tends to favor large round domains) and curvature, as specified by the Helfrich energy functional. In this study we use a Monte-Carlo simulation on the surface of a GUV to determine the equilibrium shape and phase morphology. We find that the patterns arising from these competing interactions very closely approximate those observed, that the patterned morphologies represent thermodynamically stable configurations, and that the geometric nature of these patterns is closely tied to the relative and absolute values of the model parameters.
Evidence in favor of Braak staging of Parkinson's disease

Recently, Braak and coworkers proposed a pathologic staging scheme for Parkinson disease (PD). In this staging, scheme substantia nigra pathology occurs at midstage disease, while involvement of anterior olfactory nucleus, medulla, and pontine tegmentum occur earlier. In the last stages, Lewy bodies (LBs) involve cortical areas. The general principles of the proposed staging system have been confirmed in several studies of PD, but it does not appear to fit with all LB disorders. We studied the density and distribution of LBs with alpha-synuclein immunohistochemistry in normal elderly with incidental LBs (N = 12); progressive supranuclear palsy (PSP) with incidental LBs (N = 18); Lewy body disease (LBD) with minimal or no Alzheimer type pathology (N = 52); LBD with concomitant Alzheimer disease (AD) (N = 84); and cases of AD with amygdala predominant LBs (N = 64). The proportion of cases that fit the PD staging scheme was 67% for incidental LBs; 86% for PSP with LBs; 86% for pure LBD; and 84% for LBD with AD; but only 6% for AD with amygdala predominant LBs. The PD staging scheme is valid, except in the setting of advanced AD. In this situation, LBs may be unrelated to PD and more likely related to factors inherent to AD and the selective vulnerability of the amygdala to both Alzheimer and alpha-synuclein pathologies.
Modeling and Performance Evaluation of a Large-Scale SOFC-Based Combined Heat and Power System for Biogas Utilization at a Wastewater Treatment Facility

Biogas has been identified as an attractive fuel for solid oxide fuel cells (SOFCs) due to its high methane content and its renewable status. Current experimental and modeling research efforts in this field have focused mainly on single-cell and small-scale systems performance evaluation. In this paper a large scale biogas source (∼15.5 MW) from a large wastewater treatment facility is considered for integration with an SOFC-based system. Data concerning biogas fuel flow rate and composition have been acquired from a wastewater reclamation facility in Denver and are used as inputs to a steady-state model of an SOFC combined heat and power (CHP) system developed with Aspen Plus. The proposed system concept for this application comprises an advanced SOFC system with anode gas recirculation (AGR) equipped with biogas clean-up and a waste heat recovery system. The system performance is evaluated at near atmospheric pressure with a 725°C nominal operating temperature of the fuel cell stack and system fuel utilization of 80%. The average biogas fuel input has a composition of 60% CH4, 39% CO2, and 1% N2 on a dry molar basis. The SOFC-CHP system employs 80% internal reforming at a steam-to-carbon ratio of 1.2. The system offers a net electrical efficiency of 51.6% LHV and a net CHP efficiency of 87.5% LHV. The influence of the operating parameters on the system efficiency is investigated and discussed. The individual contribution of system components to the total inefficiency of the system is quantified with an exergy analysis. Exergy analysis results indicate that the system could offer a tremendous energy efficiency improvement when compared to biogas-supplied combustion turbines currently installed at the facility which operate with an average net electrical efficiency of 25%-LHV.Copyright © 2012 by ASME
Issues and Innovations in Electronic Theses and Dissertations

This well-organized primer looks at the library’s pivotal role in producing, archiving, marketing, and providing access to electronic theses and dissertations (ETDs). As with other titles in this s...
Nonlinear dynamic analysis of quasi-symmetric anisotropic structures

An efficient computational method for the nonlinear dynamic analysis of quasi-symmetric anisotropic structures is proposed. The application of mixed models simplifies the analytical development and improves the accuracy of the response predictions, and operator splitting allows the reduction of the analysis model of the quasi-symmetric structure to that of the corresponding symmetric structure. The preconditoned conjugate gradient provides a stable and effective technique for generating the unsymmetric response of the structure as the sum of a symmetrized response plus correction modes. The effectiveness of the strategy is demonstrated with the example of a laminated anisotropic shallow shell of quadrilateral planform subjected to uniform normal loading.
Prediction of Functional Status from Neuropsychological Tests in Community-Dwelling Elderly Individuals

Age-related dysfunction of frontal systems can result in deficits in planning, organization, self-control, and awareness of problems, which are likely to affect the ability to care for one's self. The purpose of this study was to determine the relationship between age-related frontal/executive deficits and impairment in instrumental activities of daily living (IADLs) in elderly individuals. Twenty-seven community-dwelling individuals were administered a comprehensive battery of neuropsychological tests and a performance-based evaluation of IADLs. Multiple regression analyses indicated that executive function and depression severity accounted for a significant proportion of variance in IADLs, with executive function making the greatest contribution. Tests measuring other cognitive functions, such as memory, language, and spatial skills, did not contribute significantly to the prediction of functional status. Furthermore, executive measures accounted for more variance than other demographic characteristics such as general health status, age, and educational level. The results of this study indicate that executive dysfunction in normal aging may be the best predictor of functional decline. A better understanding of the mechanisms that underlie IADL skills will ultimately aid in the development of compensatory and intervention strategies designed to delay the onset of assisted living and nursing home placement.
Reconfigurable hydrophobic/hydrophilic surfaces in microelectromechanical systems (MEMS)

Fully reconfigurable hydrophobic–hydrophilic surfaces were achieved by reversibly adsorbing and removing avidin from a hydrophobic self-assembled monolayer. The adsorption process was characterized using surface plasmon resonance, while contact angle measurements were used to monitor the resulting wetting behavior. This reconfigurable approach was demonstrated in micromachined silicon channels coated with a 25 nm layer of SiO2. Hydrophilic surfaces led to spontaneous flow while pressurized flow was required along hydrophobic surfaces. By controlling the surface modification process, spatially selective flow was achieved.
Towards a Polarizable Force Field for RNA based on the Classical Drude Oscillator

RNA plays many important roles in the cell, including information transfer, gene regulation, protein synthesis, and catalysis. This diversity in function arises in part from the adoption of complex tertiary structures and interconversion between multiple conformational states in response to bound metabolites or changes in other cellular conditions. Modeling RNA with atomistic resolution using molecular dynamics (MD) simulations requires a high-quality empirical force field that can adequately describe the properties of both canonical and non-canonical structures and is sensitive to environmental conditions. To this end, we are developing a force field for RNA that includes the explicit treatment of electronic polarization using the classical Drude Oscillator model. Optimization is focused on the RNA 2′-hydroxyl group and the phosphodiester backbone targeting 2-D quantum mechanical (QM) potential energy and dipole moment surfaces in combination with condensed phase MD simulations of both canonical and non-canonical RNA structures. Parameter validation involves conducting MD simulations of various RNAs not included in the training set.
Role of net surface heat flux in seasonal variations of sea surface temperature in the tropical Atlantic Ocean

Abstract The present study used a new net surface heat flux (Qnet) product obtained from the Objective Analyzed Air–Sea Fluxes (OAFlux) project and the International Satellite Cloud Climatology Project (ISCCP) to examine two specific issues—one is to which degree Qnet controls seasonal variations of sea surface temperature (SST) in the tropical Atlantic Ocean (20°S–20°N, east of 60°W), and the other is whether the physical relation can serve as a measure to evaluate the physical representation of a heat flux product. To better address the two issues, the study included the analysis of three additional heat flux products: the Southampton Oceanographic Centre (SOC) heat flux analysis based on ship reports, and the model fluxes from the National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis and the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40). The study also uses the monthly subsurface temperature fields from the ...
Essential thrombocythemia, unremarkable cause of atypical chest pain with simple yet effective treatment: a case report

The cause of chest pain in patients presenting to the emergency room often remains unclear. We present a case of essential thrombocythemia as a novel cause of atypical chest pain, which responded dramatically to a simple treatment intervention. A 54-year-old patient presenting with atypical chest pain was found to have essential thrombocythemia as a cause for her chest pain. She responded dramatically to aspirin therapy and had no recurrence of symptoms over 3 months. Essential thrombocythemia should be considered as a differential cause in patient presenting with atypical chest pain, vasomotor symptoms and high platelet counts. These symptoms are generally more bothersome than dangerous and are usually controlled by low dose aspirin therapy.
Strain and Stress Analyses from Calcite Twin Lamellae in Experimental Buckles and Faulted Drape-Folds

Studies of calcite twin lamellae in an experimental thick-beam fold, a multilithologic, layered thin-beam buckle, and in several multilithologic faulted and drape-folded specimens provide a test of the use of these lamellae to map the strain and stress fields developed under known, yet complex, boundary conditions. Even though the number of grains available for sampling per domain of homogeneous deformation is small (8 to 100), we find that in 24 of 28 domains studied the derived orientations and relative magnitudes of the principal strain axes agree to + 30? with the corresponding inferred principal stress axes, with those inferred from accompanying microfractures and faults, and with those expected from the bending and the boundary conditions. The absolute differences in strain between those inferred from the twin lamellae and those calculated from bedding-thickness changes or from the surface strains recovered from distorted grid-lines averages + 0.01. The poorest correlations are for domains where the sample size is < 20. In addition, the twin-lamellae strain analyses permit better definitions of superposed deformation and anticlastic bending than do the corresponding stress analyses. For strains up to about 0.15, calcite twin lamellae are remarkably good indicators of the strain and stress histories of deformations.
Impact of Extreme Prematurity on Educational Outcomes at Ages 8-10 Years: Social and Biomedical Risks in Children Without Major Disability† 1302

Impact of Extreme Prematurity on Educational Outcomes at Ages 8-10 Years: Social and Biomedical Risks in Children Without Major Disability† 1302
The University as a Model of Technological Balance

"Technological balance" occurs automatically when the designer, builder, and user of a tool is the same person. "Technological imbalance" occurs when these activities become separated and in opposition to one another. Tools become menacing exoge nous objects. We see a shift in connotation of the word technology from the skill of the person to the object produced. Designers and builders create tools with the passive consent and willful ignorance of users. Curricula often contribute to this imbalance. Apprentice designers and builders receive specialized instruction in creating objects, whereas users uncritically learn the procedural requirements of the resulting objects. This system of education turns "machine tending" into a pedagogical goal. The university has the potential to become a model of technological balance for the soci ety as a whole using such means as selecting tools that encourage balance, "technology audits, " and break ing down the specializations among designers, builders, and users.