cssi/SciSciGPT-SciSciNet huggingface dataset:
Challenges for Deploying Web Services-Based E-Business Systems in SMEs

E-business initiative in many companies had started in the 1990s. These companies have recently begun to explore the use of Web Services (WS) technologies within their e-business context, since they provide an attractive, language-neutral, environment-neutral programming model that accelerates application development and integration inside and outside the enterprise. Despite these advantages, companies are slow to deploy WS because it requires a considerable shift in their application development process. While a few studies have reported on some of the reasons for this wait-and-see approach, a thorough and systematic investigation of the challenges from the stakeholders’ — providers, consumers, and standards organizations — perspective is needed. This study addresses that and provides a framework for studying the factors that impact the deployment and use of WS. The framework is used to analyze small and medium-sized enterprises (SMEs), as they play a vital role in generating employment opportunity and turnover within many major economies globally.
A Comparative Analysis and Evaluation of the DGRF-85 and IGRF-90 Candidate Models

Candidate models for the Definitive Geomagnetic Reference Field (DGRF) main field model at the 1985.0 epoch, as well as candidate models for the International Geomagnetic Reference Field (IGRF) main field model at the 1990.0 epoch along with the corresponding secular variation models at the 1992.5 epoch were evaluated against each other, and against data observations from both Project MAGNET aeromagnetic data and recently obtained Polar Orbiting Geomagnetic Survey (POGS) satellite data. Models for the 1985.0 epoch show some regional differences in model by model comparisons but, in general, are quite similar.
Change in flow stress and ductility of δ-phase Pu-Ga alloys due to self-irradiation damage

Abstract An internal state variable model for the mechanical behavior of aged Pu–Ga alloys is developed and used to predict the change of the material with accumulated self-irradiation damage or age. The material model incorporates microstructural data such as the primary irradiation-induced defect density from cascades, the density and average size of helium bubbles, the initial dislocation density, and the initial average segment length of the dislocation density as input parameters, and then evaluates the stress–strain response of a representative volume element of the material. Given this response at a single material point, the deformation behavior of tensile specimens is predicted, and it forecasts increased strength, decreased strain hardening, and more strain localization with aging. Although the material point behavior showed some slight strain softening, this strain softening is expected to be masked by statistical variations of different volume elements and by the strain rate sensitivity of the material. Hence, it is not expected to appear in the stress–strain response of macroscopic tensile specimens, and only the increase in flow stress will be measured.
Detail Preserving 3D Motion Compression Based on Local Transformation

With the advance of 3D acquisition techniques, more and more 3D motion data with fine details become available. In order to efficiently represent the data, we explored different motion compensation algorithms through conventional techniques and analyzed their performance both in theory and by experiments. A novel motion compression framework based on local transformation is proposed to solve the existing problems. Experiments show that our algorithm can achieve very high compression rate while preserving the fine details. The algorithm is easy to implement and is versatile to different applications including non-skeleton driven motion compression.
Equations on the semidirect product of a finite semilattice by a finite commutative monoid

LetComt,q denote the variety of finite monoids that satisfy the equationsxy=yx andxt=xt+q. The varietyCom1,1 is the variety of finite semilattices also denoted byJ1. In this paper, we consider the product varietyJ1*Comt,q generated by all semidirect products of the formM*N withM∈J1 andN∈Comt,q. We give a complete sequence of equations forJ1*Comt,q implying complete sequences of equations forJ1*(Com∩A),J1*(Com∩G) andJ1*Com, whereCom denotes the variety of finite commutative monoids,A the variety of finite aperiodic monoids andG the variety of finite groups.
Multicomponent Internet continuing medical education to promote chlamydia screening.

Background Low Chlamydia trachomatis screening rates create an opportunity to test innovative continuing medical education (CME) programs. Few studies of Internet-based physician learning have been evaluated with objective data on practice patterns. Design This randomized controlled trial tested a multicomponent Internet CME (mCME) intervention for increasing chlamydia screening of at-risk women aged 16 to 26 years. Setting Eligible physician offices had ≥20 patients at risk for chlamydia as defined by the Health Plan Employer Data and Information Set (HEDIS), had at least one primary care physician (internal medicine, family medicine/general practice, pediatrics) with Internet access, and participated in the study managed care organization. The 191 randomized primary care offices represented 20 states. Intervention The intervention, available from February to December 2001, consisted of four case-based learning modules, was tailored in real time to each physician based on theory of behavior change, and included office-level feedback of chlamydia screening rates. Main outcome measure HEDIS chlamydia screening rates for the pre-intervention (2000) and post-intervention (2002) periods. Results Pre-intervention screening rates for the intervention and comparison offices were 18.9% and 16.2% ( p =0.135). Post-intervention screening rates for the intervention and comparison offices were 15.5% and 12.4%, respectively ( p =0.044, adjusting for baseline performance). Conclusions The substantial decline in chlamydia screening rates observed in the comparison offices was significantly attenuated for the intervention offices. The mCME favorably influenced chlamydia screening by primary care physicians.
Using positive equality to prove liveness for pipelined microprocessors

The paper presents an indirect method to automatically prove liveness for pipelined microprocessors. This is done by first proving safety---correctness for one step, starting from an arbitrary initial state that is possibly restricted by invariant constraints. By induction, the implementation will be correct for any number of steps; we need to prove that for some fixed number of steps, n, the implementation will fetch at least one instruction that will be completed. This was proved efficiently by using the property of Positive Equality. Modeling restrictions made the method applicable to designs with exceptions and branch prediction. The indirect method and the modeling restrictions resulted in 4 orders of magnitude speedup, enabling the automatic liveness proof for dual-issue superscalar and VLIW designs.
MRI-BASED INFLOW BOUNDARY CONDITIONS FOR PATIENT SPECIFIC FLUID STRUCTURE INTERACTION MODELING OF ABDOMINAL AORTIC ANEURYSMS

Rupture of abdominal aortic aneurysm (AAA) is the 10th leading cause of death for men over age of 50 in US. The decision for surgical intervention is currently based on aneurysm diameter or its expansion rate. However, the use of these criteria for all patients is debatable. For example, small aneurysms do rupture or become symptomatic before reaching the critical diameter. Computationally predicted mechanical wall stress is considered a viable alternative criterion for rupture risk assessment. Hence, it is important to evaluate the effect of different modeling approaches on the accuracy of the predicated AAA wall stress. For computational solid stress (CSS) analysis or finite element analysis (FEA), a uniform static or transient intraluminal pressure is generally applied on the wall-lumen surface whereas in fluid-structure interaction (FSI) modeling the wall-lumen surface experiences transient and non-uniform fluid stress. An earlier comparison on idealized AAA models [1] revealed that static and transient CSS underestimate the peak wall stress (PWS) by an average 20–30% for variable wall thickness and 10% for uniform wall thickness when compared to fully coupled FSI. However, FSI-predicted stresses and strains were observed to be sensitive to inflow and outflow boundary conditions, warranting further study on a more accurate approach for FSI modeling. Though significant work has been performed on modeling outflow boundary conditions [2], studies on the sensitivity of computed stress or strain to the type of FSI inflow boundary condition is scarce [2–4]. We hypothesize that a FSI framework with a patient specific velocity boundary condition derived from magnetic resonance imaging (MRI) data applied to patient specific AAA geometry would provide better accuracy of PWS calculations compared to a FEA model. In this work, we present a framework where the AAA geometry is reconstructed from computed tomography (CT) images, on which FSI simulations were performed with inlet velocity components extracted from patient MR images of the abdominal aorta. Fully coupled FSI simulations were performed and results were compared with CSS simulations with uniform transient pressure boundary conditions.Copyright © 2012 by ASME
Minimizing Back Exchange in the Hydrogen Exchange-Mass Spectrometry Experiment

The addition of mass spectrometry (MS) analysis to the hydrogen exchange (HX) proteolytic fragmentation experiment extends powerful HX methodology to the study of large biologically important proteins. A persistent problem is the degradation of HX information due to back exchange of deuterium label during the fragmentation-separation process needed to prepare samples for MS measurement. This paper reports a systematic analysis of the factors that influence back exchange (solution pH, ionic strength, desolvation temperature, LC column interaction, flow rates, system volume). The many peptides exhibit a range of back exchange due to intrinsic amino acid HX rate differences. Accordingly, large back exchange leads to large variability in D-recovery from one residue to another as well as one peptide to another that cannot be corrected for by reference to any single peptide-level measurement. The usual effort to limit back exchange by limiting LC time provides little gain. Shortening the LC elution gradient by 3-fold only reduced back exchange by ~2 %, while sacrificing S/N and peptide count. An unexpected dependence of back exchange on ionic strength as well as pH suggests a strategy in which solution conditions are changed during sample preparation. Higher salt should be used in the first stage of sample preparation (proteolysis and trapping) and lower salt (G20 mM) and pH in the second stage before electrospray injection. Adjustment of these and other factors together with recent advances in peptide fragment detection yields hundreds of peptide fragments with D-label recovery of 90 %±5 %.
Hydrogen bonding Part 46. Thermodynamic and IR study of stability and structure of tetraethylammonium fluoride·2.75H2O, tetraethylammonium fluoride·2.00H2O, tetramethylammonium fluoride·3.00H2O, and tetraethylammonium fluoride·5.00H2O

Abstract An equilibrium vapor pressure study of the dissociation of tetraethylammonium fluoride·2.75H2O to the dihydrate demonstrates that hydrogen bonds between H2O and F−, and between H2O and H2O are broken in this process. This conclusion is based on comparison of the observed enthalpy of dissociation with values calculated for various patterns of hydrogen bond breaking. For these calculations a value of approximately 14 kcal mol−1 for HOH⋯F− hydrogen bonds in the hydrates was estimated by comparison of crystalline state and gas phase water—halide hydrogen bond strengths. Coupled with the IR spectrum, this information leads to a proposed formulation for the water—fluoride ion structure of the dihydrate in which C2h planar (H2O·F−)2 clusters are linked by H2O molecules which bridge between H2O in one cluster and F− in an adjacent cluster. Material with the composition of tetramethylammonium trihydrate is an extraordinarily hard, crystalline substance; dissociation vapor pressure measurements suggest that only HOH⋯OH2 hydrogen bonds are broken as this material dehydrates to the dihydrate. Stoichiometric liquid tetraethylammonium pentahydrate can be nucleated to a crystalline solid for which diffraction studies should be possible.
Travel Writing and Tourism in Britain and Ireland

This collection of essays on the home tour fills in an important gap in the growing field of travel writing studies. As Benjamin Colbert points out, existing studies of the home tour have a specifi...
Effects of age on dynamic accommodation

Visual accommodation plays a critical role in one's visual perception and activities of daily living. Age-related accommodation loss poses an increased risk to older adults' safety and independence. Although extensive effort has been made towards understanding the effect of age on steady-state accommodation, dynamic aspects of accommodation is still unknown. A study was therefore conducted to investigate age-related dynamic accommodative characteristics utilising a modified autorefractor. Ten individuals from each of three age groups (i.e. younger group: 20 to 29 years old; middle-aged group: 40 to 49 years old; older group: 60 to 69 years old) were recruited and their dynamic accommodation responses were examined. The laboratory experiment was designed to assess dynamic accommodation associated with an abrupt change from a constant far target (400 cm, 50 cd/m2) to a near target (70 cm, 100 cd/m2 or 20 cd/m2), which aimed to simulate car dashboard reading behaviour while driving. The results of the study ...
Oscillating elastic defects: Competition and frustration

We consider a dynamical generalization of the Eshelby problem: the strain profile due to an inclusion or ``defect" in an isotropic elastic medium. We show that the higher the oscillation frequency of the defect, the more localized is the strain field around the defect. We then demonstrate that the qualitative nature of the interaction between two defects is strongly dependent on their separation, frequency, and direction, changing from a ``ferromagnetic''- to an ``antiferromagnetic''- like behavior. We generalize to a finite density of defects and show that the interactions in assemblies of defects can be mapped to $XY$-spin-like models and describe implications for frustration and frequency-driven pattern transitions.
Electrodiagnosis of upper limb weakness in acute quadriplegia

Clinical and neuropathologic observations after cervical spinal cord injury suggest varying involvement of gray and white matter. The resulting upper limb weakness may reflect varying degrees of upper motoneuron (UMN) and/or lower motoneuron (LMN) involvement. This study uses electrophysiologic measures, including compound muscle action potential (M response) amplitude, root mean square (RMS) of the surface electromyographic activity during voluntary muscle contractions and the firing rate of motor units, to distinguish UMN and LMN weakness in upper extremities after acute quadriplegia. M response amplitude did not correlate with strength; many muscles had large M responses given their strength. These muscles manifest: (1) high M/RMS ratios (ratio of electrically elicited to voluntarily recruited electromyographic activity) and (2) slow firing rates of single motor units during maximal isometric contractions. For muscles with normal M amplitudes, M/RMS ratio correlates inversely with strength. For muscles with normal M/RMS ratios, M amplitude correlates positively with strength. Cluster analysis was used to distinguish UMN, LMN or Mixed types of weakness. Distinguishing these different types of weakness in acute quadriplegia may allow individualized rehabilitation for the type of weakness present.
Infrared Photography As A Diagnostic Tool For The Burn Wound

The classification of burns is an area of considerable confusion (Ref. 1,2). The popu-lar description of first, second, and third degree was originated over 150 years ago by Boyer. This classification was based on superficial appearance and was used almost exclusively with minor modifications until about 30 years ago. Burn physicians then began to realize that the depth of injury was of prime importance, and not this superficial appearance. Thus, there evolved a two-category description which is defined as follows: The partial-thickness burn is a wound in which sufficient epithelial elements remain to allow spontaneous skin repair, and the full-thickness burn is a wound in which the epithelial elements necessary for spontaneous skin repair have been destroyed. In the latter case, skin repair can occur by contraction of the wound and cell migration from the edge. When this peripheral regrowth is not possible or adequate, grafting is necessary.© (1974) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The energetic/variational interpretation of Poincaré's criterion for the orbital stability of limit cycles of autonomous systems

Abstract This paper supplies an energetic interpretation and derivation of Poincare's criterion for the orbital stability of the limit cycles of the autonomous (quasilinear) equation q + q = Q(q,q) → eF(q,q) ( q = coordinate , overdot = time derivative, e = small number , F, Q = msmooth nonlinear functions of q,q ), based on the principles of Lagrangean/Hamiltonian dynamics. Specifically, it is shown that the time derivative of the “net work(-ing)” (= a linear differential energetic expression equal to the virtual work of Q , minus the first virtual variation of the system's total energy), equals this net work(-ing) times δQ/δq ; a subsequent integration over the limit cycle's solution and period yields the well-known time-integral stability test. The connection of the above with: i) the standard Stoker/McCuskey derivation of the criterion, and ii) the well-known Liouville's theorem of volume change in phase-space are pointed out.
Reduced NRT supplies through a quitline: Smoking cessation differences

Introduction: Quitlines (QLs) provide effective smoking cessation treatment. The most cost-effective protocol for nicotine replacement therapy (NRT) has not been established. The current study compares self-reported 7-day abstinence rates among light to moderate smokers (≤20 cigarettes per day [CPD]) when a state QL reduced NRT supplies from 8 to 4 weeks. Methods: The study (n = 1,710) included Colorado QuitLine enrollees who requested free NRT. Analysis compared light to moderate smokers when 8- versus 4-week NRT supplies were available; the nonequivalent control group was heavy smokers (>20 CPD), who were consistently eligible for 8 weeks of NRT during the same time period. Results: Under the reduced NRT protocol, abstinence declined by nearly one fourth among light to moderate smokers (29.9% vs. 39.3%, p < .01). Heavy smokers reported no difference in abstinence rates (28.6% vs. 28.4%, p = nonsignificant). Discussion: Reducing NRT supplies from 8 to 4 weeks was associated with a one-fourth reduction in smoking abstinence rates among users of a state telephone QL. Future research should experimentally assess cost-effectiveness of 4- versus 8-week NRT protocols in QLs and should examine potentially mediating or moderating factors, such as history-affected expectancies regarding NRT and smoking cessation.
Prediction of board-level performance of WLCSP

The board level performance of both thermal cycling test and drop test is investigated to ensure good design and robust manufacturing of the WLCSP. The solder joint fatigue life is usually assumed as the judging criterion for the board-level thermal cycling performance of WLCSPs. For the board-level drop test, the solder joints usually fail due to the dynamic impact stress with high strain rate. The investigation of prediction of board-level thermal cycling test and drop test of WLCSPs is performed by FEA modeling. Several fundamental issues of WLCSP are addressed. The concerned issues include: silicon thickness, back side laminate (BSL), PCB with/without buried copper planes, PCB material, and the design rule of depopulated solder array. Simulation results show that the silicon thickness, BSL, and depopulated solder joints of the WLCSP do not have significant impact on the board-level drop test performance. The WLCSP with thinner silicon, no BSL, and with 4 corner solder balls removed, may improve the board-level thermal cycling performance.
Mind wandering behind the wheel: performance and oculomotor correlates.

OBJECTIVE: An experiment studied the frequency and correlates of driver mind wandering. BACKGROUND: Driver mind wandering is associated with risk for crash involvement. The present experiment examined the performance and attentional changes by which this effect might occur. METHOD: Participants performed a car-following task in a high-fidelity driving simulator and were asked to report any time they caught themselves mind wandering. Vehicle control and eye movement data were recorded. RESULTS: As compared with their attentive performance, participants showed few deficits in vehicle control while mind wandering but tended to focus visual attention narrowly on the road ahead. CONCLUSION: Data suggest that mind wandering can engender a failure to monitor the environment while driving. APPLICATION: Results identify behavioral correlates and potential risks of mind wandering that might enable efforts to detect and mitigate driver inattention. Keywords: Driver distraction; Language: en
Building Creativity: Collaborative Learning and Creativity in Social Media Environments

Purpose – Using a systems-based approach to creativity and a sociocultural constructionist approach to learning, this study aims to highlight how creative ideas emerge within a community and spread amongst its members. Design/methodology/approach – Using a design-based approach to research, this study took place within the social media environment, Quest Atlantis. Chat data were collected from 85 participants and screenshots were taken of the virtual architecture designed and built by players in the Quest Atlantis environment, in an effort to explore the nature of creativity and collaborative learning within the context of virtual 3D architectural construction. Findings – The findings illustrate the rise and spread of creativity in online communities and also point to the social and cultural nature of creativity. Research limitations/implications – This study, the first of its kind, focuses on how creativity operates within a single community in order to draw implications about digital creativity more broadly. Practical implications – Implications for designing virtual and physical communities to promote creativity are discussed. Originality/value – Documenting and analyzing an entire creative system in the everyday world can be a challenging endeavor. Social media, by contrast, offer an opportunity to document, describe, and analyze creativity, extend Csikszentmihalyi’s work into the realm of social media and push back on current conceptions of digital creativity.
Presence of cysteinyl leukotrienes in asthmatic patients with chronic sinusitis.

Introduction: The association between asthma and sinusitis has long been recognized. Numerous studies point to a complex, yet undeniable relationship between asthma and chronic sinusitis and rhinitis. There have also been extensive attempts to characterize the inflammatory mechanisms of both disorders. Increasingly, the cysteinyl leukotrienes, a potent group of inflammatory mediators, have gained attention as important contributors to the manifestation of both disorders. Leukotriene production has been shown to be upregulated in the bronchial tissue of asthmatics. Our study sought to determine if leukotriene production was increased in the sinus mucosa of asthmatics with chronic sinusitis. Study Design: Prospective study. Methods: Nasal polyp tissue was evaluated from 27 consecutive patients undergoing elective polypectomy. The presence of asthma was determined by patient history, their medical record, and use of asthma medication. Sinus tissue was extracted during the course of endoscopic surgery. Cysteinyl leukotrienes (CysLT) were quantified by a sensitive competitive enzyme immunoassay, and the levels of CysLT were compared in the group with and without asthma. Results: Cysteinyl leukotrienes were detected in 23 of 27 patients. The average level of LTC 4 in non-asthmatic patients was 25.6 picograms (pg)/g. The average amount of LTC 4 in asthmatic patients with sinusitis was 19.2 pg/g. There was no significant difference between the two groups (P = .64). Conclusions: The presence of asthma does not correlate with increased levels of leukotrienes in the sinus mucosa of patients with chronic sinusitis.
New Directions for the Study of Gender Role Attitudes A Cluster Analytic Investigation of Masculinity Ideologies

This article presents a new application of cluster analytic methodology to the study of gender role attitudes. We developed a preliminary typology of men's profiles of masculinity ideology in a sample of 217 upper-level undergraduates stratified across all academic divisions at a large, public university in the midwest. Based on cluster analyses of four dimensions of masculinity ideology, five patterns of endorsement were identified: Moderately Traditional, High Status/Low Violence, Nontraditional, High Violence/Moderately Traditional, and Traditional. Preliminary validity of this cluster solution was demonstrated by significant differences by cluster in gender role egalitarianism.
In-plane lunar injection opportunities from an orbiting space station

Correction of in-plane injection delay caused by orbital plane regression in lunar launch from orbiting space station
Gender issues related to graduate student attrition in two science departments

This study explored the gender issues that contributed to the differential attrition rate of men and women graduate students in two science departments (biology and chemistry) at a large research university. Departmental records were used to compute the student attrition rate while surveys from 170 students, and interviews with 32 of them, were used to explore students' perspectives on the reasons affecting the attrition of men and women graduate students in each department. Analysis of the data indicated a significantly larger student attrition rate in chemistry than in biology. In each department the attrition rate for women was also significantly larger than the attrition rate for men. The study uncovered different gender issues, in each department, related to the significantly larger attrition rate for women students.
Transient analysis of coupled, tapered transmission lines with arbitrary nonlinear terminations

A fast and efficient method of simulating the time-domain transient response of coupled, tapered transmission lines is presented. A time-domain scattering parameter formulation is used to derive the simple closed-form expression for the voltage variables for uniform lossless lines; this expression is applied to tapered lines by dividing the lines into many uniform section. Computational efficiency and stability are achieved using recursive time-domain algorithms. When a quasi-TEM propagation mode is assumed, the method is applicable to nonlinear terminations and inhomogeneous dielectric media. Memory requirements are minimized and are independent of the number of time steps. Simulation results showed good agreement with experimental results. >
The Potential of Virtual Reality Technologies to Improve Adherence to Weight Loss Behaviors

A significant proportion of the global population is obese, foreshadowing an epidemic of chronic disease. Self-monitoring (of diet, exercise, and body weight), decreasing energy intake, and increasing energy expenditure are robust predictors of successful weight loss. However, few individuals consistently practice these behaviors, making long-term weight loss and maintenance unlikely. Technologies afford unique opportunities to overcome barriers and increase the reach of traditional obesity interventions. In this article, we introduce ENGAGED, a technology-enhanced modification of the Diabetes Prevention Program designed to improve adherence to weight loss behaviors. Using a treatment implementation framework, we suggest how virtual reality technologies might further improve the delivery, receipt, and enactment of ENGAGED to maximize patient impact.
SIA: Secure information aggregation in sensor networks

In sensor networks, data aggregation is a vital primitive enabling efficient data queries. An on-site aggregator device collects data from sensor nodes and produces a condensed summary which is forwarded to the off-site querier, thus reducing the communication cost of the query. Since the aggregator is on-site, it is vulnerable to physical compromise attacks. A compromised aggregator may report false aggregation results. Hence, it is essential that techniques are available to allow the querier to verify the integrity of the result returned by the aggregator node. We propose a novel framework for secure information aggregation in sensor networks. By constructing efficient random sampling mechanisms and interactive proofs, we enable the querier to verify that the answer given by the aggregator is a good approximation of the true value, even when the aggregator and a fraction of the sensor nodes are corrupted. In particular, we present efficient protocols for secure computation of the median and average of the measurements, for the estimation of the network size, for finding the minimum and maximum sensor reading, and for random sampling and leader election. Our protocols require only sublinear communication between the aggregator and the user.
Motorola's IRIDIUM system: low-Earth orbit global cellular communications network

Summary form only given. The technical parameters which led to Motorola's announced IRIDIUM system were discussed. The IRIDIUM system is a worldwide, satellite-based, cellular, personal communications system primarily intended to provide commercial, low-density, mobile service via portable, mobile, or transportable user units, using low-profile antennas, to millions of users throughout the world. Calls can be made and received anywhere in the world with a personal, portable unit. Small smart satellites are internetworked to form the network's backbone. Small, battery-powered, cellular-telephone-like user units communicate directly to the satellites. Gateways (Earth stations) provide the interface from the satellites to the individual postal, telephone, and telegraph authorities. The system is intended to be compatible with terrestrial cellular telephone systems installed, or being installed, in densely populated areas by providing a similar service everywhere else in the world. >
The utility of prophylactic laparoscopic cholecystectomy in transplant candidates.

Background This study addresses the impact of laparoscopic cholecystectomy prior to kidney or pancreas transplant. Patients and methods Between January 1991 and July 1993, 551 patients were listed for transplant. Gallbladder ultrasound became part of the standard evaluation for all transplant candidates in October 1991. Pretransplant laparoscopic cholecystectomy was recommended for all patients found to have gallstones. To assess the benefit of this policy, patients transplanted prior to routine ultrasound (Group I; n = 88) were compared to those listed or transplanted after routine ultrasound (Group II; n = 406). Results In Group I, 18% developed gallstone complications requiring surgery. Surgical morbidity occurred in 14% and mortality in 7% of these operations. Graft loss occurred in 20% having biliary complications versus 7% among other recipients. In Group II, gallstones were detected in 10%, and 9% subsequently had laparoscopic cholecystectomy with no morbidity or mortality. Conclusions Transplant recipients with unsuspected gallstones were found to have a high incidence of acute biliary complications. Urgent biliary surgery carried significant morbidity and mortality in these immunosuppressed patients and appeared to increase the risk of graft failure as well. A policy of screening gallbladder ultrasound and pretransplant laparoscopic cholecystectomy seems to reduce these concerns and is recommended for all transplant candidates.
The role of environmental gradients in non-native plant invasion into burnt areas of Yosemite National Park, California

Fire is known to facilitate the invasion of many non-native plant species, but how invasion into burnt areas varies along environmental gradients is not well-understood. We used two pre-existing data sets to analyse patterns of invasion by non-native plant species into burnt areas along gradients of topography, soil and vegetation structure in Yosemite National Park, California, USA. A total of 46 non-native species (all herbaceous) were recorded in the two data sets. They occurred in all seven of the major plant formations in the park, but were least common in subalpine and upper montane conifer forests. There was no significant difference in species richness or cover of non-natives between burnt and unburnt areas for either data set, and environmental gradients had a stronger effect on patterns of non-native species distribution, abundance and species composition than burning. Cover and species richness of non-natives had significant positive correlations with slope (steepness) and herbaceous cover, while species richness had significant negative correlations with elevation, the number of years post-burn, and cover of woody vegetation. Non-native species comprised a relatively minor component of the vegetation in both burnt and unburnt areas in Yosemite (percentage species = 4%, mean cover < 6.0%), and those species that did occur in burnt areas tended not to persist over time. The results indicate that in many western montane ecosystems, fire alone will not necessarily result in increased rates of invasion into burnt areas. However, it would be premature to conclude that non-native species could not affect post-fire succession patterns in these systems. Short fire-return intervals and high fire severity coupled with increased propagule pressure from areas used heavily by humans could still lead to high rates of invasion, establishment and spread even in highly protected areas such as Yosemite.
Simulating novel EM effects

Numerical simulation is a useful tool for evaluating new technologies. In order to analyze new plasmonic and photonic band-gap devices we have re-written and extended our finite-difference time-domain (FDTD) simulator, TEMPEST, into a guided-wave analysis system. We illustrate our new simulation capabilities with investigations into two devices: 1) a sub-wavelength grating mirror, and 2) plasmon-enhanced Daguerreotype photographs.
A look at damped harmonic oscillators through the phase plane

Damped harmonic oscillations appear naturally in many applications involving mechanical and electrical systems as well as in biological systems. Most students are introduced to harmonic motion in an elementary ordinary differential equation (ODE) course. Solutions to ODEs that describe simple harmonic motion are usually found by investigating the roots of a corresponding characteristic polynomial and ultimately written out as a time series to be graphed. Although this approach is standard, students often fail to connect the relationship between position and velocity that one achieves using phase plane analysis. The purpose of this article is to illustrate how the phase plane analysis and transformations can be used to gain a deep understanding of damped harmonic oscillations.
A balloon-expandable intravascular stent for obliterating experimental aortic dissection.

Abstract Acute aortic dissection is a life-threatening condition. Aggressive hypotensive drug therapy is the initial treatment of choice, although emergent surgical intervention is often warranted. We evaluated the efficacy of a balloon-expandable intravascular stent for the internal obliteration of aortic dissection. It is a flexible, continuous, complex coil cut to the length needed at the time of insertion. It can be positioned in curved vessels, including the aortic arch. The stent was inserted in the thoracic and abdominal aorta of 12 dogs (group I). Six weeks after implantation the dogs underwent angiography and the stents were explanted for light and scanning electron microscopy. There were no instances of stent migration or change in configuration. The aortas did not rupture. All branch vessels remained patent. Light and scanning electron microscopy illustrated neointimal incorporation into the vascular wall except at orifices. Thoracic dissections were created surgically in an additional 24 mongrel dogs. Twelve dogs received stents immediately after creation of the dissection (group II). All 12 dissections were obliterated. Twelve dogs were allowed to recover after creation of the dissection to observe the natural history of that lesion (group III). Within 1 week, in group III, there were three deaths because of aortic rupture; eight dissections persisted, and one resealed spontaneously. Stents were placed in the eight persistent dissections. All eight dissections were obliterated. In both groups, after 6 weeks of stent placement, aortography was repeated, and stents were explanted for light and scanning electron microscopy. There were no instances of rupture. All branch vessels remained patent with no evidence of thrombosis. We conclude that because of its unique characteristics, the stent effectively obliterates the false lumen of experimental acute aortic dissections without occluding side branches, damaging the aorta, or inducing thrombosis. (J VASC SURG 1990;11:707-17.)
Annealing Techniques For Unsupervised Statistical Language Learning

Exploiting unannotated natural language data is hard largely because unsupervised parameter estimation is hard. We describe deterministic annealing (Rose et al., 1990) as an appealing alternative to the Expectation-Maximization algorithm (Dempster et al., 1977). Seeking to avoid search error, DA begins by globally maximizing an easy concave function and maintains a local maximum as it gradually morphs the function into the desired non-concave likelihood function. Applying DA to parsing and tagging models is shown to be straightforward; significant improvements over EM are shown on a part-of-speech tagging task. We describe a variant, skewed DA, which can incorporate a good initializer when it is available, and show significant improvements over EM on a grammar induction task.
Counterfactual Thinking and Ethical Decision Making A New Approach to an Old Problem for Marketing Education

The present study extends understanding of the self-regulatory aspects of ethical decision making by integrating and exploring relationships among counterfactual thinking, attribution, anticipatory emotions, and ethical decision-making constructs and processes. Specifically, we examine the effects of a manipulation designed to stimulate a counterfactual mind-set, which is found to significantly affect negative anticipatory emotions and intention associated with unethical conduct. Furthermore, we explore the basis of these effects by delineating and supporting responsibility attributions working through perceived negative consequences to influence both negative anticipatory emotions and intention to perform the unethical behavior. This research addresses both academic and managerial imperatives in the marketing education literature as to how to effectively influence ethical decisions through an understanding of how individuals combine theoretically significant cognitions.
The natural history and incidence of Yersinia pestis and prospects for vaccination

Plague is an ancient, serious, infectious disease which is still endemic in regions of the modern world and is a potential biothreat agent. This paper discusses the natural history of the bacterium and its evolution into a flea-vectored bacterium able to transmit bubonic plague. It reviews the incidence of plague in the modern world and charts the history of vaccines which have been used to protect against the flea-vectored disease, which erupts as bubonic plague. Current approaches to vaccine development to protect against pneumonic, as well as bubonic, plague are also reviewed. The considerable challenges in achieving a vaccine which is licensed for human use and which will comprehensively protect against this serious human pathogen are assessed.
CONTROL OF SINGULARLY PERTURBED MARKOV CHAINS: A NUMERICAL STUDY

This work is devoted to numerical studies of nearly optimal controls of systems driven by singularly perturbed Markov chains. Our approach is based on the ideas of hierarchical controls applicable to many large-scale systems. A discrete-time linear quadratic control problem is examined. Its corresponding limit system is derived. The associated asymptotic properties and near optimality are demonstrated by numerical examples. Numerical experiments for a continuous-time hybrid linear quadratic regulator with Gaussian disturbances and a discrete-time Markov decision process are also presented. The numerical results have not only supported our theoretical findings but also provided insights for further applications.
Millimeter‐wave signal generation using semiconductor diode lasers (invited paper)

Methods of millimeter-wave signal generation are presented using frequency multiplication by optical comb generation, direct generation using optical oscillators, and mixing between CW optical sources. © 1993 John Wiley & sons, Inc.
Femtosecond laser polishing of optical materials

Technologies including magnetorheological finishing and CNC polishing are commonly used to finish optical elements, but these methods are often expensive, generate waste through the use of fluids or abrasives, and may not be suited for specific freeform substrates due to the size and shape of finishing tools. Pulsed laser polishing has been demonstrated as a technique capable of achieving nanoscale roughness while offering waste-free fabrication, material-specific processing through direct tuning of laser radiation, and access to freeform shapes using refined beam delivery and focusing techniques. Nanosecond and microsecond pulse duration radiation has been used to perform successful melting-based polishing of a variety of different materials, but this approach leads to extensive heat accumulation resulting in subsurface damage. We have experimentally investigated the ability of femtosecond laser radiation to ablate silicon carbide and silicon. By substituting ultrafast laser radiation, polishing can be performed by direct evaporation of unwanted surface asperities with minimal heating and melting, potentially offering damage-free finishing of materials. Under unoptimized laser processing conditions, thermal effects can occur leading to material oxidation. To investigate these thermal effects, simulation of the heat accumulation mechanism in ultrafast laser ablation was performed. Simulations have been extended to investigate the optimum scanning speed and pulse energy required for processing various substrates. Modeling methodologies and simulation results will be presented.
Electric Load Classification by Binary Voltage–Current Trajectory Mapping

Characterization of electric loads provides opportunities to incorporate detailed energy usage information into applications such as protection, efficiency certification, demand response, and energy management. This paper proposes a low computational cost, but yet accurate method, to extract signatures for load classification and characterization. Instead of utilizing digital signal processing and frequency-domain analysis, this paper abstracts the similarity of voltage–current (V–I) trajectories between loads and proposes to map V–I trajectories to a grid of cells with binary values. Graphical signatures can then be extracted for many applications. The proposed method significantly reduces the computational cost compared with existing frequency-domain signature extraction methods. Test results show that an average of over 99% of success rate can be achieved using the proposed signatures.
DNA content histogram and cell-cycle analysis.

Publisher Summary This chapter reviews guidelines for DNA content histogram analysis and the principles and advances in methods of analysis. The careful and more uniform use of guidelines for DNA content and cell-cycle analysis should lead to greater accuracy and reproducibility in performing and reporting ploidy and cell-cycle measurements. If this is done, then this simple methodology can be applied with greater confidence over a wider range of clinical settings. The future of DNA cytometry also includes greater use of multiparameter DNA analyses, especially the use of cell-type and proliferationspecific antibodies. Although the added information that is derived from the multiparameter analysis will help improve accuracy, most of these analyses will still involve cell-cycle analysis of gated histograms or bivariate histogram regions. Thus, DNA content and cell-cycle analysis will retain importance well into the future.
Metrics for V&V of cyber defenses

There is a need for a disciplined approach for evaluating a cyber defense prior to its introduction into an operational environment. This is necessary to assess whether the benefits of the defense will be worth its costs and risks. A traditional V&V workflow is adapted for this purpose. The considerations it must take into account are described, as is the collection and presentation of pertinent metrics. An example of this workflow is given for a cyber defense against a "reconnaissance attack" that threatens information integrity and confidentiality.
Panama Canal Update

The Panama Canal extension project is, arguably, the most important current transportation project in the world today. It will allow most Post-Panamax vessels to use the canal and is likely to change transportation flow patterns throughout North and South America, as well as port loads and transportation flows inland in the Americas. This paper gives a short update on the status of the project and its likely impacts.
Enhanced Gas-Side Heat Transfer in Rectangular Micro-Honeycombs

Gas and air-side heat transfer is ubiquitous throughout many technological sectors, including HVAC (heating, ventilating, and air conditioning) systems, thermo-electric power generators and coolers, renewable energy, electronics and vehicle cooling, and forced-draft cooling in the petrochemical and power industries. The poor thermal conductivity and low heat capacity of air causes air-side heat transfer to typically dominate heat transfer resistance even with the use of extended area structures. In this paper, we report design, analysis, cost modeling, fabrication, and performance characterization of micro-honeycombs for gas-side heat transfer augmentation in thermoelectric (TE) cooling and power systems. Semi-empirical model aided by experimental validation was undertaken to characterize fluid flow and heat transfer parameters. We explored a variety of polygonal shapes to optimize the duct shape for air-side heat transfer enhancement. Predictions using rectangular micro-honeycomb heat exchangers, among other polygonal shapes, suggest that these classes of geometries are able to provide augmented heat transfer performance in high-temperature energy recovery streams and low-temperature cooling streams. Based on insight gained from theoretical models, rectangular micro-honeycomb heat exchangers that can deliver high performance were fabricated and tested. High- and low-cost manufacturing prototype designs with different thermal performance expectations were fabricated to explore the cost-performance design domain. Simple metrics were developed to correlate heat transfer performance with heat exchanger cost and weight and define optimum design points. The merits of the proposed air-side heat transfer augmentation approach are also discussed within the context of relevant thermoelectric power and cooling systems.Copyright © 2012 by ASME