cssi/SciSciGPT-SciSciNet huggingface dataset:
Analyzing and Detecting Emerging Quality-Related Concerns across OSS Defect Report Summaries

Quality-related concerns are often coined with the terms non-functional requirements, architecturally significant requirements, and quality attributes. Collectively, these qualities affect non-behavioral concerns of the software system such as reliability, usability, security, or maintainability among others. As a byproduct of a long-term maintenance effort, these system qualities tend to erode over time, causing system-wide failures that emerge via quality-related bugs. Quality-related bugs can have a detrimental impact on system’s sustained stability and can chiefly hinder its core functionality. Typically, for the developers, to manually examine these high-impacted quality-related bugs can become prohibitively expensive and impractical task to attain. This is often a case with bugs that are reported from medium or large-sized projects such as Eclipse. To alleviate this problem, we built a quality-based classifier to automatically detect these emerging quality-related concerns from textual descriptions of bug report summaries. Specifically, we leveraged a weighted combination of semantics, lexical, and shallow features in conjunction with the Random Forest ensemble learning method. Finally, we discuss the practical applicability of our classifier for mapping and visualizing quality-related concerns into the codebase with an example from the Derby project. To summarize, this work represents an effort and an early awareness to improve the underlying management of issue tracking systems and stakeholder requirements in open-source communities.
Non-Uniform Stable Solutions to Reaction-Diffusion Equations: Applications to Ecological Pattern Formation

In the mathematical theory of ecological communities, there are two major subjects: (i) the temporal dynamics of interacting populations and (ii) the spatial pattern of the community. Historically, these subjects have undergone quite independent development, and have been concerned with very different sorts of questions.
Neural modeling as one approach to machine learning

In this paper I propose that a neural modeling approach is reasonable for investigating certain low-level learning processes such as are exhibited by invertebrates. These include habituation, sensitization, classical conditioning, and operant conditioning. Recent work in invertebrate neurophysiology has begun to provide much knowledge about the underlying mechanisms of learning in these animals. Guided by these findings, I am constructing simulated organisms which will display these basic forms of learning.
Difference in Germ Cell Tumors of the Reproductive Tract in Men and Women

Publisher Summary This chapter concentrates on the germ cell tumors (GCTs). Germ cells (primordial cells) are cells stored in the male and female reproductive tracts (testis and ovary) that carry the reproductive machinery in both sexes. A unique characteristic of these cells is that they divide by meiosis retaining only half of the cell chromosomes (haploid); thus, when the male sperm cell and female ovum join, the resulting human embryo has normal diploid somatic cell number of chromosomes. Although they have the same function and originate from the same cells, their development, number, maturation, and pathology vary between men and women. Germ cell tumors constitute a remarkably heterogeneous group of neoplasms that can arise from the germ cells in the gonads (testis and ovary) or in extragonadal sites (mainly in the sacrococcygeal region, retroperitoneum, mediastinum, and central nervous system). Despite their common cells of origin, GCTs differ greatly between men and women. In women, ovarian GCTs comprise 15–20% of all ovarian neoplasms, and only 3–5% of these are malignant. Therefore, while GCTs occur more frequently in women than in men, most of these tumors in women are of a benign nature. The pathogenesis, clinical presentation, treatment, and outcome of ovarian germ cell and epithelial cancer are very different. On the other hand, 98% of testicular neoplasms are comprised of testicular GCTs, making it the most common malignancy in American men between the ages of 15 and 34. To understand this significant difference in GCTs between sexes it is necessary to describe the difference in germ cell development.
Korean Social Work Students’ Attitudes Toward Homosexuals

For this article, the Hudson and Ricketts Index of Attitudes toward Homosexuality (IAH) was used to measure levels of homophobia in a convenience sample of 124 students enrolled in social work programs in two major universities in the Republic of South Korea. The results indicated that BSW and MSW Korean students had high levels of homophobia, particularly in comparison to U.S. samples. In-class discussion of homosexuality was found to be significantly associated with lower levels of homophobia. The authors review these and other research findings and discuss implications for social work education in South Korea and the United States.
Transferrin secretion in response to different modes of FSH stimulation and cycloheximide in superfused Sertoli cell cultures.

The influence of different modes of FSH stimulation and cycloheximide on transferrin secretion by rat Sertoli cells was investigated using a superfusion culture system. Sertoli cells from 18-day-old rats were cultured in serum-free medium on Matrigel-covered slides first in static conditions for 19 hours, and then superfused at a flow rate of 2.5 ml/hour. After an equilibration period of 48 hours to establish the basal rate of transferrin secretion, the cultures were exposed to various modes of FSH stimulation. Sertoli cells stimulated intermittently (20 min/2 hours) up to 22 hours responded to each consecutive FSH pulse with a rapid increase of transferrin secretion followed by a decline toward basal values. Continuous 22-hour exposure to FSH elicited an immediate increase followed by irregular fluctuations and a transient decline towards the baseline. With either mode of FSH stimulation, there was a secondary prolonged increase in transferrin secretion. Although cultures stimulated intermittently or continuously during the entire experimental period (22 hours) secreted similar cumulative amounts of transferrin (10.8 ± 0.5 μg and 11.1 ± 0.8 μg, respectively), there was a direct correlation between the secreted amount of transferrin and the duration of FSH exposure up to 8 hours. Addition of cycloheximide decreased both basal and FSH-stimulated transferrin secretion. However, even when cycloheximide was added 1 hour before FSH, an early secretory peak in response to FSH was still observed. It was concluded that, regardless of the mode of FSH stimulation, transferrin secretion shows a biphasic response in which an initial increase within minutes of FSH exposure is followed by a return to basal levels, and then a delayed and prolonged secondary increase. Secondly, cumulative amounts of transferrin can vary with the mode of FSH stimulation; finally, Sertoli cells appear to secrete mainly newly synthesized transferrin, but a small storage pool may also exist for immediate release by FSH independently of new protein synthesis.
Reconfigurable fault-tolerant control system for a segmented telescope testbed

The design of fault-tolerant control systems is one of the leading issues for highly critical systems. In fact, fault-tolerant control system is used to improve system reliability after failure, maintainability which decreases maintenance time and survivability which is critical in preventing damage. Most control systems are designed to meet performance requirements in the presence of modeling errors, noise, and disturbances. Yet in the presence of faults these robust control systems can not guarantee closed-loop stability or performance. Therefore, a class of control systems called active fault-tolerant control systems that can tolerate various types of faults at the same time maintain acceptable level of performance is considered. This paper presents the research conducted at the NASA sponsored Structures, Pointing and Control Engineering (SPACE) laboratory in designing a decentralized reconfigurable control (DRC) system for a segmented reflector testbed. The objective of the DRC system is to develop controllers that satisfy performance requirements for both normal and/or anomalous (failure) situations. The objective is accomplished by integrating a nominal controller, sensor fault detection and isolation (SFDI), and reconfigurable controllers. The number of computational operations needed to implement a reconfigurable control system for large-scale systems is very large; therefore a centralized reconfigurable control system is usually not feasible. However, with a decentralized approach the total task of the reconfigurable control system is divided into a number of relatively small tasks, which can be implemented by a number of processors working in parallel. The objective of this research is broader in the sense that the methods and tools developed in this study shall be useful for and applicable to a wide variety of reconfigurable control applications.
Investigating and Managing the Rapid Emergence of White‐Nose Syndrome, a Novel, Fatal, Infectious Disease of Hibernating Bats

White-nose syndrome (WNS) is a fatal disease of bats that hibernate. The etiologic agent of WNS is the fungus Geomyces destructans, which infects the skin and wing membranes. Over 1 million bats in six species in eastern North America have died from WNS since 2006, and as a result several species of bats may become endangered or extinct. Information is lacking on the pathogenesis of G. destructans and WNS, WNS transmission and maintenance, individual and site factors that contribute to the probability of an outbreak of WNS, and spatial dynamics of WNS spread in North America. We considered how descriptive and ana- lytical epidemiology could be used to fill these information gaps, including a four-step (modified) outbreak investigation, application of a set of criteria (Hill's) for assessing causation, compartment models of disease dynamics, and spatial modeling. We cataloged and critiqued adaptive-management options that have been either previously proposed for WNS or were helpful in addressing other emerging diseases of wild animals. These include an ongoing program of prospective surveillance of bats and hibernacula for WNS, treatment of individual bats, increasing population resistance to WNS (through vaccines, immunomodulators, or other methods), improving probability of survival from starvation and dehydration associated with WNS, modi- fying hibernacula environments to eliminate G. destructans, culling individuals or populations, controlling anthropogenic spread of WNS, conserving genetic diversity of bats, and educating the public about bats and bat conservation issues associated with WNS.
Allowable Bearing Capacity of Initially Bent Piles

A method for the calculation of the maximum lateral deflection, maximum soil reaction, and maximum bending moment of an axially loaded, initially bent pile is presented. By limiting the maximum soil reaction to one-half to one-third of the ultimate lateral resistance of the soil, and by limiting the maximum stress in the pile to one-fourth of the yield, or ultimate, strength of the pile material, it is possible to estimate rapidly the axial load that can be safely applied. The use of this method in design is illustrated by a numerical example.
Properties of the positive time-frequency distribution functions

Joint positive distributions of time and frequency which satisfy the correct marginals exist and can be readily obtained. In this presentation we generalize the continuous case previously considered to the discrete time case and the two dimensional situation.
The psychophysical approach in manual lifting--a verification study.

An experiment was conducted to verify the psychophysical methodology used for determining lifting capabilities of workers. After estimating during a 25-min period what they could lift for 8 h, male...
Spatial Predictive Queries

In this seminar, we address spatial predictive queries both in Euclidian spaces and over road networks. We provide a definition for various types of spatial predictive queries, describe current research trends, and envision future directions. We present practical application scenarios and emphasize the roadblocks that are holding industry back from the commercialization of spatial predictive queries. This seminar targets audience in mobile data management, spatiotemporal query processing, mobile crowd sourcing, and tracking of moving objects.
Multiscale Bayesian image reconstruction in positron emission tomography

In recent years, various approaches to overcome the problems associated with iterative statistical image reconstruction methods have been investigated, including issues such as slow convergence rate, costly computational time and nonuniform correction efficiency. A multiscale Bayesian image reconstruction algorithm based on a 1-D wavelet technique is proposed. In this approach, the authors first apply a wavelet transform to the sinogram measurements, which yields a multiresolution object representation. The image is reconstructed at the corresponding grid by the Bayesian image reconstruction algorithm for each scale level in the frequency space; the backprojector is also modified to match each corresponding resolution scale. After the low-frequency components of the image have been recovered sufficiently on the coarser scale level, the resulted image is used as the starting point for the finer level at a new iteration. An important feature in the authors' new approach is that the wavelet decomposition is carried out in the sinogram space, while multiple grids are also used in the reconstructed image space.
An Olfactory Sensory Neuron Line, Odora, Properly Targets Olfactory Proteins and Responds to Odorants

The site for interactions between the nervous system and much of the chemical world is in the olfactory sensory neuron (OSN). Odorant receptor proteins (ORPs) are postulated to mediate these interactions. However, the function of most ORPs has not been demonstrated in vivo or in vitro. For this and other reasons, we created a conditionally immortalized cell line derived from the OSN lineage, which we term odora. Odora cells, under control conditions, are phenotypically similar to the OSN progenitor, the globose basal cell. After differentiation, odora cells more closely resemble OSNs. Differentiated odora cells express neuronal and olfactory markers, including components of the olfactory signal transduction pathway. Unlike other cell lines, they also efficiently target exogenous ORPs to their surface. Strikingly, differentiated odora cells expressing ORPs respond to odorants, as measured by an influx of calcium. In particular, cells expressing one ORP demonstrate a specific response to only one type of tested odorant. Odora cells, therefore, are ideal models to examine the genesis and function of olfactory sensory neurons.
Excitation and Adaptation in the Detection of Hydrogen Ions by Taste Receptor Cells: A Role for cAMP and Ca2+

The role of intracellular cAMP and Ca2+ in the excitation and adaptation of taste responses by HCl was investigated by direct measurement of intracellular pH (pHi) in polarized taste receptor cells...
The Effects of Institutional Investor Preferences on Ownership Changes and Stock Prices around Corporate Spin-offs

Because spin-offs create new firms with characteristics markedly different from the original firm, institutional investors pre-committed to certain investment styles and/or subject to fiduciary restrictions have incentives to rebalance their portfolios at the time of the spin-off. Prior articles in the business press and academic journals claim that the large volume of trading related to this rebalancing creates short-term price pressure in stocks of the entities emerging from the spin-off. In this paper, we examine whether corporate spin-offs lead to significant changes in the holdings of institutional investors and whether these changes do create temporary price pressure. We find strong evidence that investment strategy and fiduciary restrictions affect institutional investor demand for the stocks after spin-offs. However, our results indicate that matching of institutional buying and selling is sufficiently complete in most cases to allow for large volumes of shares to change hands without prices deviating from fundamentals.
A Characteristic Particle Method for Traffic Flow Simulations on Highway Networks

A characteristic particle method for the simulation of first order macroscopic traffic models on road networks is presented. The approach is based on the method particleclaw, which solves scalar one dimensional hyperbolic conservation laws exactly, except for a small error right around shocks. The method is generalized to nonlinear network flows, where particle approximations on the edges are suitably coupled together at the network nodes. It is demonstrated in numerical examples that the resulting particle method can approximate traffic jams accurately, while only devoting a few degrees of freedom to each edge of the network.
Feasibility of recording clot lysis with the thermometric clot detector.

We investigated the possibility of continuously recording the process of clot lysis with a thermometric clot detector. Experiments in which fibrinolytic activators and inhibitors were used demonstrate that the detection system, without any mechanical modifications, is suitable for monitoring the complete coagulation process from clot formation to the ultimate lysis of the clot itself.
Measuring the efficacy of inventory with a dynamic input–output model

Abstract This paper extends the recently developed dynamic inoperability input–output model (DIIM) for assessing productivity degradations due to disasters. Inventory policies are formulated and incorporated within the DIIM to evaluate the impact of inventories on the resilience of disrupted interdependent systems. The Inventory DIIM can provide practical insights to preparedness decision making through explicit tradeoff analysis of multiple objectives, including inventory costs and economic loss reductions. The model is demonstrated in several illustrative examples to depict various nuances of inventory policies. The paper then culminates in a case study that utilizes input–output and inventory accounts from the Bureau of Economic Analysis.
Microtubule patterning in apical epidermal cells of Vinca minor preceding leaf emergence

Serial thin sectioning for electron microscopy was carried out on the cortical cytoplasm of surface cells of the apical dome ofVinca minor. The cellulose reinforcement pattern in the outer epidermal walls forming this surface is known to correlate well with the decussate phyllotaxis pattern. The purpose of this study was to determine the location of microtubules immediately under these epidermal walls as a first step toward finding out how the cellulose pattern arises. First, correspondence between the patterns of microtubules and cellulose was checked. Second, the role of potential orienting cues for the alignment of microtubule arrays in specific cells was evaluated.
Thermal rearrangement of pyridinium anhydrobases: migration of N-substituents to methine carbon

Abstract N-Benzyl and N-methyl groups migrate to the methine carbon atom on thermolysis of pyridinium anhydrobases. Cross-over experiments indicate an intermolecular reaction, probably involving homolysis.
Uncertainties in Projections of Human-Caused Climate Warming

Increased atmospheric greenhouse gases resulting from human activities have produced a sharp increase in the potential to warm the climate to levels that may have serious implications. Predictions of future climate changes in response to these greenhouse gas increases depend almost completely upon physically based mathematical models of the climate system. The strengths and weaknesses of these models to project various aspects of climate change are evaluated in terms of a "betting odds" approach to provide guidance to the policy deliberation process.
Applications of fuzzy integrals to handwriting recognition

Two applications of fuzzy integrals to handwritten word recognition are discribed. Fuzzy integrals are used in a dynamic programming based, offline handwritten word recognition algorithm. This algorithm finds optimal matches between word images and strings in lexicons. Fuzzy integrals are used to compute the match scores. Fuzzy integrals are also used in a hidden Markov model based, offline handwritten word recognition algorithm. In this case, fuzzy measures and integrals are used as alternatives to probabilistic measures and ordinary integrals. Results are presented on standard data sets consisting of real images collected form United States Postal Service mail stream.
Spectropolarimetry and Radiative Transfer Modeling of Three Proto-Planetary Nebulae

We measured the spectrum of polarization for three proto-planetary nebulae (PPNs), IRAS 17411-2411, IRAS 08005-2356, and IRAS 04296+3429, and made model calculations with the dust-scattering Monte Carlo code DIRTY and the dust emission code 2Dust. We show that high levels of polarization in these PPNs correlate with extreme asymptotic giant branch (AGB) superwind mass-loss rates in excess of 10-4 M☉ yr-1. All three objects show evidence for evacuated lobes cleared by collimated fast winds, and two indicate a significant equatorial mass enhancement. Our best-fit models require sharply peaked grain size distributions, suggesting that most of the light is being scattered by grains of a characteristic size in IRAS 17441-2411 and IRAS 08005-2356. IRAS 17441-2411 and IRAS 08005-2356 have lobes with wide opening angles, perhaps produced by deflection of a polar jet from an accreting companion by the AGB superwind. Modeling the spectropolarimetry of IRAS 04296+3429 indicates a point-symmetric, multipolar morphology in the PPN phase. The modeling of spectropolarimetry and other observations of PPNs provides a powerful way to constrain circumstellar morphology and dust parameters.
Agent-Based Modeling for Simulation of Complex Business Systems: Research Design and Validation Strategies

This article aims to provide a synopsis of agent-based modeling and how to adapt an agent-based research strategy for the scientific study of complex business systems. Agent-based systems have been a popular field of study in computer science for some time. While computer science-related research has been focused on the artifact itself, such as computational languages and algorithms, research in the management sciences is explicitly focused on business problems. Research in Information Systems (IS) has begun to advance knowledge in the use of agent-based systems as a means to seek different, computational explanations for business phenomena that have eluded scientific inquiry reliant on traditionalâ€”specifically, law and axiomaticâ€”explanation (Kimbrough, 2003). The focus on business problems requires a different research approach than what is successful in computer science. Key modifications include first, the explicit articulation of benefits specific to the management sciences, and second, instrument validation.
Basic Biological Sciences The Effect of Acid-etching on Caries-like Lesions Treated with Stannous Fluoride

The effect of acid-etching on SnF2-treated caries-like lesions was investigated. The results suggested that remineralization occurred, limited to the superficial portions of the lesions. In addition, we observed etching patterns which are comparable to those described for etched sound enamel.
Information expectation from unmanned aircraft swarms

This paper lays the groundwork for modeling the quantification of sensor coverage for Unmanned Aircraft (UA) swarms of sensors. The concept of information expectation is defined, elaborated, and illustrated. Areas of interest (AOI)s are analyzed from a swarm standpoint to determine the quantity of coverage afforded by a swarm of multiple sensor-laden UAs. This work also investigates the coverage of AOIs as determined by the mission duration, area of the region, and time-variable swarm geometry. By experimentation using simulation, we gain insight into the quantifiable influence of varying swarm sizes and configurations on area coverage. This in turn allows validation of formulae and algorithms for computing approximation of expected opportunities for relevant information collection.
Orientation and tunneling in monolayer methane: CHD3 physisorbed onto NaCl(100)

Polarized infrared spectra of CHD3 adsorbed on NaCl(100) in the temperature range 5 to 33 K are reported. Doublet features are observed in the ν1 and ν4 spectral regions. Analysis of the ν1 doublet reveals one transition dipole perpendicular to the surface and another transition dipole at 70±15° from the surface normal. These features are assigned to the C–H stretching vibrations of molecules oriented in a tripod conformation with the hydrogen in the “top” position (H-up) and in a tripod with the hydrogen in one of the “base” positions (H-down), respectively. The fraction of H-up orientational isomers increases with decreasing temperature. It is shown that an energy splitting between H-up and H-down orientational isomers of 6.9±0.5 cm−1 can explain the temperature dependence. Several possible explanations of the energy splitting are explored. Tunneling between orientational isomers is shown to be the only mechanism of reorientation consistent with the observed conversion time scale.
Effects of Physical Context on Stereotyping of Mexican American Males

Based on Trope 's (1986) model of perception, the effects of physical context on stereo-typing and willingness to affiliate with Mexican American males were examined. In this two-part study, the effect of context alone was explored by showing a stilled videoframe of a library room and a crime scene without people in them. Results indicated that the context affected expectations of the type of people who might be seen in those contexts. In the second study, the interaction of context and stereotyping was examined by placing two Mexican American males (one of whom was "stereotypical") in scholar, crime, and neutral contexts. Results reveal an interaction between context and target stereotyping whereby physical context did not affect stereotyping except when the target could not be easily categorized by ethnicity alone. Discussion centers on contributions of these studies to the literature on context, stereotyping of Mexican Americans, and future research.
The influence of automatic speech recognition accuracy on the performance of an automated speech assessment system

The effectiveness of automated scoring systems for evaluating spoken language proficiency depends greatly on the quality of the automatic speech recognition (ASR) output that is used to calculate the features for the scoring model. In this paper, we examine the effects of ASR word error rate (WER) on the scores produced by a system for automated scoring of non-native English speaking proficiency, as well as on the scoring model features (especially content features) in order to demonstrate the impact of ASR improvements on the performance of the automated speech assessment system. Five different sets of transcriptions with varying degrees of WER ranging from 0% to 52% (including four sets of ASR hypotheses and manual transcriptions) were obtained for a dataset of spoken responses from a pilot administration of an assessment of non-native English speaking proficiency. The experimental results show that higher performing ASR leads to better performance in the automated assessment system; furthermore, the correlation between human and automated scores drops substantially with an increase in WER from 10.7% to 28.9%, whereas the correlation changes little within the following two ranges of WERs: 0% to 10.7% and 28.9% to 52%. A detailed analysis of the features used in the scoring model shows that the ASR errors have a bigger impact on the content features than the delivery and language use features.
Gender Issues in Multicultural Children's Literature—Black and Third-World Feminist Critiques of Appropriation, Essentialism, and Us/Other Binary Oppositions

In light of the concepts of appropriation and essentialism, othering, and binary oppositions, the author will examine the interrelation between various feminist theories and gender representation in multicultural children and young-adult literature. Additionally, the author will address the practical implications of those theories and concepts for the classroom.
Stability of tea polyphenol (-)-epigallocatechin-3-gallate and formation of dimers and epimers under common experimental conditions

(-)-Epigallocatechin-3-gallate (EGCG), the most abundant and biologically active compound in tea, has been extensively studied for its activities related to disease prevention in animal models and in vitro. However, its stability under different experimental conditions has not been well-characterized. In the present study, the stability of EGCG in animal drinking fluid and under cell culture conditions and the factors that affect its stability under these conditions were investigated. Our results demonstrated that auto-oxidation and epimerization are the two major reactions causing the instability of EGCG. The structures of the major oxidation products, EGCG dimers, were identified. The rates of these reactions were affected by the temperature, pH, the partial pressure of oxygen, the level of antioxidants, the concentration of EGCG, and other components of tea. In future studies with EGCG, its stability should be considered in order to avoid possible artifacts.
Numerical method of lines for analysis of vehicle-bridge dynamic interaction

Abstract In this paper, a finite element-based formulation and implementation of vehicle-bridge dynamic interaction problems are presented. A variety of vehicle models are considered. The problem formulation takes into account the dynamic effects of multiple vehicles traversing on multiple lanes, with arbitrary and variable speeds and directions. The consideration of various vehicle traversing conditions allows for the interaction between vehicles and the bridge superstructure, as well as among vehicles, to be represented in a more realistic manner. The spatial discretization of the governing partial differential equation of the vehicle-bridge system is based on the finite element method. The resulting matrix ordinary differential equation is then discretized with respect to time on the basis of the Newmark method. The process of reduction of a partial differential equation into a matrix ordinary differential equation through a spatial discretization procedure, and then solving this expression using a time integration technique is referred to as the numerical method of lines. Since the consideration of vehicle-bridge interaction introduces nonlinearity into the problem formulation, a multi-predictor-corrector scheme is adopted in the solution procedure to obtain accurate results. The solution algorithm is implemented into a computer code developed by the authors, and numerical examples are solved to illustrate the validity and efficiency of the proposed formulation and solution methodology. Furthermore, the numerical results are detailed in order to highlight the dynamic effects of multiple vehicles on the behavior of bridge superstructures.
Forecasting performance of market share models: an assessment, additional insights, and guidelines

Abstract The research provides an assessment of the relevant literature on market share models and identifies the need for further research. Additional insights are generated in this study by using point-of-sale scanners for evaluating the forecasting performance of market share models under various conditions. Specifically, weekly store-level scanner data for four frequently purchased product categories-saltine crackers, baking chips, diapers and toilet tissue, and simulated data are used in this study. Consistent with theoretical expectations, the attraction models estimated by GLS produce the best forecasts even (1) at the brand level, and (2) when competitors' actions are predicted. However, the superiority of the attraction models is diminished when systematic errors are introduced to the values of the competitors' predictor variables in the holdout sample. In fact, naive models outperform all types of econometric models when large errors are present in the competitors' predictor variables, and among the econometric models, linear models produce better forecasts than attraction models. The need for estimating the models with GLS (as opposed to OLS) with the use of cross-sectional time-series data is also illustrated. Finally, guidelines are developed for practitioners and researchers on the usefulness of market share models for forecasting.
Boundary layer analysis of plane strain shear cracks propagating steadily on an impermeable plane in an elastic diffusive solid

Abstract Matched asymptotic expansions are used to examine the stress and pore pressure fields near the tip of a plane strain shear (mode II) crack propagating on an impermeable plane in a linear elastic diffusive solid. For propagation speeds V that are large compared with c/l, where c is the diffusivity and l is the crack-length, boundary layers are required at the crack-tip and on the line ahead of the crack. The latter is required to meet the condition of no flow across this plan; in contrast, for propagation on a permeable. plane, a boundary layer is required on the crack faces behind the tip. As for the permeable plane, the solution in the crack-tip boundary layer reveals that the stress field near the crack-tip has the form of the usual linear elastic field with a stress intensity factor [ (1 − v u (1 − v) ]K (c), where K(e) is the stress intensity factor of the outer elastic field, v is the Poisson's ratio governing slow (drained) deformation, and vu ⩾ v is the Poisson's ratio governing rapid (undrained) deformation. Thus. coupling between deformation and fluid diffusion reduces the local value of the stress intensity factor and. hence, stabilizes against rapid propagation. For the permeable plane, the pore pressure goes to zero as the crack-tip is approached along any ray. In contrast, for the impermeable plane, a closed-form solution for the pore pressure in the cracktip boundary layer reveals that the pore pressure at the crack-tip is non-zero, but bounded.
Surface-active N-acylglutamate: IV. Physicochemical properties of triethanolamine long chain N-acylglutamates

The physicochemical properties of triethanolamine long chain N-acylglutamates are described. The monotriethanolamine salts were less soluble in water and superior in surface activity, compared with the corresponding ditriethanolamine salts. The monotriethanolamine salt showed weak acidity in an aqueous solution. There were some differences between optically active and racemic N-acylglutamates, especially in the values of critical micelle concentration.
Surgical Management of Primary Lung Cancer

Despite advancements in systemic treatment and the understanding of tumor biology, the mainstay for the treatment of lung cancer remains its resection. All patients with lung cancer should be considered surgical candidates until they are proven to have contraindications to resection. This article reviews preoperative assessment and the operative technique for the surgical treatment of lung cancer. As with other surgical specialties, thoracic surgery is moving towards minimally invasive techniques that are reducing morbidity, mortality, and length of stay. This advance is allowing patients an earlier recovery from major pulmonary surgery.
Does mutational robustness inhibit extinction by lethal mutagenesis in viral populations

Lethal mutagenesis is a promising new antiviral therapy that kills a virus by raising its mutation rate. One potential shortcoming of lethal mutagenesis is that viruses may resist the treatment by evolving genomes with increased robustness to mutations. Here, we investigate to what extent mutational robustness can inhibit extinction by lethal mutagenesis in viruses, using both simple toy models and more biophysically realistic models based on RNA secondary-structure folding. We show that although the evolution of greater robustness may be promoted by increasing the mutation rate of a viral population, such evolution is unlikely to greatly increase the mutation rate required for certain extinction. Using an analytic multi-type branching process model, we investigate whether the evolution of robustness can be relevant on the time scales on which extinction takes place. We find that the evolution of robustness matters only when initial viral population sizes are small and deleterious mutation rates are only slightly above the level at which extinction can occur. The stochastic calculations are in good agreement with simulations of self-replicating RNA sequences that have to fold into a specific secondary structure to reproduce. We conclude that the evolution of mutational robustness is in most cases unlikely to prevent the extinction of viruses by lethal mutagenesis.
New Methods for Molecular Motor and Cell Motility Research

Several novel methods for high-speed, high resolution microscopy have enabled new insights into function of molecular motors in vitro and in live cells. Several groups have developed methods to track the position and orientation of bi-functional organic fluorophores or quantum rods bound to specific motor subunits. We have now improved the time resolution by time-multiplexing excitation polarization every 100 μs and resolving structural changes by the consequent sudden changes in photon collection rates. In addition, we developed a multi-channel change-point method to detect structural states within the noisy signals and estimate rotations to within a few photons. These improvements enabled new insights into the walking mechanism of myosin V: we directly observe 10-20 ms periods of high mobility while myosin V detached heads search for actin. The gradual left-handed path of myosin V is produced by intermittent large side-ways motions among long stretches of straight walking where the lever arms mostly tilt in a plane very close to that containing the actin filament. For in vivo studies, detecting forces and motions of intracellular cargos have been compromised, until recently, by uncertainties about calibrating optical traps in cells. In the last year, four groups published novel methods for improving trap calibration in living cells. In our method, the thermal fluctuations of a phagocytosed bead are analyzed together with its motions upon sinusoidal excitation over a series of frequencies, giving trap sensitivity and local sub-diffusive viscoelastic parameters of the cytoplasm. This method is insensitive to active biological processes in the cell, as the forced response is used to resolve the elastic responses of the trap and the environment. Forces on these cargos indicate several kinesin and dynein motors operating near force balance. Supported by NIH grants P01GM087253 and R01GM086352.
Ultramarathon trail running comparison of performance-matched men and women.

Purpose: To determine whether women matched with men for age and performance in a 50-km trail ultramarathon performed differently than the men in 80- and 161-km trail ultramarathons. Methods: Race results from 1990 to 2007 were examined to identify finishers of the Way Too Cool 50-km Race, the American River 80-km Race, and the 161-km Western States Endurance Run in the same year. Matching of women with men for age (mean difference = 1 yr) and 50-km finish time (mean absolute variation = 1.5%) yielded 86 unique pairs from which 161-km performances were compared. A subset of 39 pairs allowed for comparison of all three races. Results: Mean ages of the men and women were 42-44 yr, and mean +/- SD of 50-km running speed was 152 +/- 20 m[middle dot]min-1 for both sexes. Mean +/- SD running speeds for the 80-km race (151 +/- 20 and 150 +/- 22 m[middle dot]min-1 for the women and men, respectively) and for the 161-km race (102 +/- 13 and 103 +/- 12 m[middle dot]min-1 for the women and men, respectively) were not different between the women and men. Conclusions: Women and men who are matched for 50-km trail running performance also perform similarly in trail runs of 80- and 161-km distances.
A new technique for volumetric sampling of sediment cores for concentrations of pollen and other microfossils

Abstract An accurate volumetric method is described to extract small sediment samples from lake cores. A cylindrical section is sliced from the core and its center removed with a small boring device. The original sediment volume is not distorted, and sampling error is significantly less than that reported for other volumetric techniques. The method was developed to study absolute pollen concentrations, but is suitable for other microfossils as well.
New Tools for Genome Modification in Human Embryonic Stem Cells

Two recent papers outline improvements in gene editing technology that may facilitate the analysis of signaling networks important for development. The systems developed by both Thyagarajan and coworkers (Thyagarajan et al., 2007) in Nature Biotechnology, and Lombardo and colleagues (Lombardo et al., 2007) in Stem Cells, have the potential to advance our understanding of human embryonic stem cells.
Electron Microscopy Study of Fatigue Crack Initiation in Ni3Al Single Crystals

Transmission electron microscopy of single-slip oriented Ni3Al single crystals cyclically deformed at room temperature revealed a high density of dislocation dipoles and point defect clusters. The majority of the defect clusters were identified by weak-beam TEM to be of vacancy type. The observations of circular perfect dislocation loops, Frank loops, and spherical voids revealed the evidence of vacancy condensation during fatigue cycling at room temperature. Together with SEM observations of surface topography, it is suggested that fatigue crack initiation in Ni3Al single crystals can be rationalized by formation of microvoids at PSB/matrix interfaces.
Test-Retest Reliability and Criterion Validity of a Motion Video, CD-ROM Program Designed to Allow Youth with Disabilities to Select Preferred Jobs:

Consistent with person-centered planning and federal legislation, a video CD-ROM program was used to help youth with disabilities identify their job preferences. The program was administered to 56 participants at 60-day intervals. Results indicated that selections of general work conditions were highly consistent whereas selections of specific job choices were slightly less consistent. Validation procedures consisted of comparing the video CD-ROM program to the Reading-Free Vocational Interest Inventory - Second Edition (RFVII : 2) (Becker, 2000). The video CD-ROM program selections did not correlate highly with the RFVII: 2 selections. However, they correlated highly with general interest areas (i.e., occupational sample areas) of the RFVII: 2. The study represents an initial attempt to evaluate the reliability and criterion validity of the video CD-ROM program.
Response of pulmonary venous admixture. A means of comparing therapies

Patients who require cardiopulmonary bypass have a reproducible increase in interstitial pulmonary water and pulmonary venous admixture, a decrease in functional residual capacity, and a mild arterial hypoxemia. Therefore, such patients are good subjects for evaluating therapy with positive end-expiratory pressure and steroids, both of which are controversial. We sought to determine if the response of the pulmonary venous admixture to varying concentrations of inspired oxygen could affect the apparent efficacy of these types of therapy. Results of our study are presented.
The synthesis of amino acids and sugars on an inorganic template from constituents of the prebiotic atmosphere

Inelastic Electron Tunnelling Spectroscopy (IETS) has been used to identify the reaction products present on an alumina surface when it is exposed to likely components of the earth's prebiotic atmosphere. The alumina barrier of Al-AlOx-Pb tunnelling junctions have been exposed to water; aqueous ammonia; wet carbon monoxide gas and to aqueous formaldehyde vapour under normal atmospheric conditions at room temperature. The water spectrum shows strong coincidence with that of a genuine sample of formic acid. It is proposed that atmospheric CO2 is involved in this surface catalyzed reaction. The aqueous ammonia spectrum is assigned as an amino acid species produced from ammonia, water and atmospheric carbon dioxide. This spectrum compares very closely with the tunnelling spectrum of a genuine sample of glycine. The wet carbon monoxide spectrum and the aqueous formaldehyde spectrum have been produced by an infusion doping process. These spectra of CO and aqueous formaldehyde are assigned as a sugar like polymer or a sugar formed on the alumina surface. A tunnelling spectrum of D(−) fructose has been produced to aid this assignment. The role of an inorganic template such as alumina in the original prebiotic synthesis of amino acids and sugars is considered.
Inotropes in the beta-blocker era

Beta-adrenergic blocking agents are now standard treatment for mild to moderate chronic heart failure (CHF). However, although many subjects improve on beta blockade, others do not, and some may even deteriorate. Even when subjects improve on beta blockade, they may subsequently decompensate and need acute treatment with a positive inotropic agent. In the presence of full beta blockade, a beta agonist such as dobutamine may have to be administered at very high (> 10 μg/kg/min) doses to increase cardiac output, and these doses may increase afterload. In contrast, phosphodiesterase inhibitors (PDEIs) such as milrinone or enoximone retain their full hemodynamic effects in the face of beta blockade. This is because the site of PDEI action is beyond the beta-adrenergic receptor, and because beta blockade reverses receptor pathway desensitization changes, which are detrimental to PDEI response. Moreover, when the combination of a PDEI and a beta-blocking agent is administered long term in CHF, their respective efficacies are additive and their adverse effects subtractive. The PDEI is administered first to increase the tolerability of beta-blocker initiation by counteracting the myocardial depressant effect of adrenergic withdrawal. With this combination, the signature effects of beta blockade (a substantial decrease in heart rate and an increase in left ventricular ejection fraction) are observed, the hemodynamic support conferred by the PDEI appears to be sustained, and clinical results are promising. However, large-scale placebo-controlled studies with PDEIs and beta blockers are needed to confirm these results.