cssi/SciSciGPT-SciSciNet huggingface dataset:
Variability in temporary emigration rates of individually marked female Weddell seals prior to first reproduction

In many species, temporary emigration (TE) is a phenomenon, often indicative of life-history characteristics such as dormancy, skipped reproduction, or partial migration, whereby certain individuals in a population are temporarily unobservable at a particular site. TE may be a flexible condition-dependent strategy that allows individuals to mitigate effects of adverse conditions. Consequently, TE rates ought to be highly variable, but sources of variations are poorly understood for most species. We used data from known-aged female Weddell seals (Leptonychotes weddellii) tagged in Erebus Bay, Antarctica, to investigate sources of variation in TE rates prior to reproduction and to evaluate possible implications for age-specific probability of first reproduction. TE rates were near 1 the year after birth, decreased to an average of 0.15 (SE = 0.01) by age 8, and were similar thereafter. TE rates varied substantially from year-to-year and were lower for seals that attended reproductive colonies the previous year than for seals that did not attend (e.g., ψ(i,age 8)(UU) - ψ(i, age 8)(PU) = 0.22). Recruitment rates were marginally greater for seals that did attend than for seals that did not attend colonies the previous year. For Weddell seals specifically, our results suggest that (1) motivation to attend colonies varied temporally, (2) as seals grew older they had increased motivation to attend even before reproductive maturity, and (3) seals appear to follow various attendance strategies. More broadly, our results support the idea of TE as a variable, condition-dependent strategy, and highlight the utility of TE models for providing population and life-history insights for diverse taxa.
Spin relaxation and coherence times for electrons at the Si / SiO 2 interface

While electron spins in silicon heterostructures make attractive qubits, little is known about the coherence of electrons at the Si/SiO2 interface. We report spin relaxation (T1) and coherence (T2) times for mobile electrons and natural quantum dots at a 28Si/SiO2 interface. Mobile electrons have short T1 and T2 of 0.3 us at 5 K. In line with predictions, confining electrons and cooling increases T1 to 0.8 ms at 350 mK. In contrast, T2 for quantum dots is around 10 us at 350 mK, increasing to 30 us when the dot density is reduced by a factor of two. The quantum dot T2 is shorter than T1, indicating that T2 is not controlled by T1 at 350 mK but is instead limited by an extrinsic mechanism. The evidence suggests that this extrinsic mechanism is an exchange interaction between electrons in neighboring dots.
Prevalence of Mental Disorders and Utilization of Mental Health Services in Two American Indian Reservation Populations: Mental Health Disparities in a National Context

OBJECTIVE: The American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project (AI-SUPERPFP) provided estimates of the prevalence of DSM-III-R disorders and utilization of services for help with those disorders in American Indian populations. Completed between 1997 and 1999, the AI-SUPERPFP was designed to allow comparison of findings with the results of the baseline National Comorbidity Survey (NCS), conducted in 1990–1992, which reflected the general United States population. METHOD: A total of 3,084 tribal members (1,446 in a Southwest tribe and 1,638 in a Northern Plains tribe) age 15–54 years living on or near their home reservations were interviewed with an adaptation of the University of Michigan Composite International Diagnostic Interview. The lifetime and 12-month prevalences of nine DSM-III-R disorders were estimated, and patterns of help-seeking for symptoms of mental disorders were examined. RESULTS: The most common lifetime diagnoses in the American Indian ...
Boundary detection and volume determination of the left ventricle from a cineangiogram.

Abstract This paper is concerned with a method to detect left ventricular boundaries and the subsequent volume computation from a cineangiogram by a digital computer. It will first describe three digital techniques: (1) to restore the original dimensions by a logarithmic transformation; (2) to reduce noise by averaging images; and (3) to subtract images after and before dye injection, and then a boundary detection method based on statistical principles and heuristics. A method to locate the aortic valve will also be described. Experimental results on several cine frames will be presented to demonstrate the feasibility of these techniques. Once the boundary of the ventricle is determined, the computation of the volume is performed by the usual Simpson's rule.
Ischemic ulcerative colitis following inferior mesenteric arterial ligation.

Postoperative ischemic ulcerative colitis, caused by high ligation of the inferior mesenteric artery, has been described and literature pertinent to this condition has been reviewed. Suggestions concerning prevention, early recognition and treatment are offered.
The role of cytochrome P450lpr in deltamethrin metabolism by pyrethroid-resistant and susceptible strains of house flies

Abstract The LPR strain of house fly is highly resistant to pyrethroid insecticides and this resistance is associated with high levels of monooxygenase activity and total cytochromes P450. To evaluate the role of P450 lpr (the major P450 in LPR house flies) in pyrethroid resistance, an antiserum specific for house fly cytochrome P450 lpr was tested for its ability to inhibit cytochrome P450 monooxygenase-dependent metabolism of the pyrethroid insecticide deltamethrin. Treatment of microsomes from pyrethroid resistant LPR house flies with anti-P450 lpr antiserum resulted in 97% of the radiolabel being recovered as deltamethrin compared to 76% in the normal serum control. There was no significant difference in the amount of deltamethrin recovered from microsomes of susceptible (S+) flies treated with normal serum or anti-P450 lpr antiserum compared to the carbon monoxide-inhibited control. However, there was statistically significant inhibition of specific metabolite production in both strains. Using LPR microsomes, seven NADPH-dependent products of [ 14 C]deltamethrin metabolism could be identified by thin-layer chromatography, designated as B, C, D, E, F, G, and H (origin). Metabolites B, C, D, and H were the major metabolites. Formation of metabolites B, C, and H was inhibited by anti-P450 lpr while D was increased. In S+ microsomes, only metabolites C, D, and E were consistently detected and anti-P450 lpr inhibited formation of C and D while E was unchanged. The primary metabolites inhibited by the antiserum in LPR appear to be modifications of the acid portion of the deltamethrin molecule, and the major metabolites increased by antiserum treatment were oxidations on the alcohol portion of the molecule, suggesting that P450 lpr preferentially attacks the gem-dimethyl group of deltamethrin. Pyrethroid-resistant LPR flies, topically dosed with a sublethal dose of deltamethrin, rapidly metabolized and excreted polar metabolic products. Similarly, microsomes from LPR house flies exhibited rapid cytochrome P450-dependent metabolism of deltamethrin. This study indicates that P450 lpr contributes to monooxygenase-dependent deltamethrin resistance in LPR house flies.
Phase separation in crystallizable multiblock poly(ether-ester) copolymers with poly(tetramethylene isophthalate) hard segments

Abstract The process of isothermal crystallization and phase separation in poly(tetramethylene isophthalate) (PTMI) and multiblock copolymers of PTMI with poly(tetramethylene oxide) (PTMO) is examined by differential scanning calorimetry. Morphology development is studied from the supercooled liquid to the completion of crystallization for compositions ranging from 30 to 100 wt% PTMI over a wide range of isothermal crystallization temperatures. A model is suggested whereby phase separation in the copolymers proceeds in a manner similar to crystallization of the homopolymer, implying phase-mixed non-crystalline regions with inhomogeneous mobilities. The experimentally observed multiple endotherm behaviour in the PTMI/PTMO copolymers is a characteristic of the hard segment, and is also observed in the PTMI homopolymer.
Sec3p Is a Spatial Landmark for Polarized Secretion in Budding Yeast

Exocytosis in yeast occurs at plasma membrane subdomains whose locations vary with the cell cycle, but the primary protein determinants of these sites are unknown. A functional fusion of Sec3 protein with green fluorescent protein (Sec3-GFP) localizes to the site of polarized exocytosis for each cell-cycle stage, where it colocalizes with Sec4p and Sec8p. Sec3-GFP localization is independent of secretory pathway function, of the actin and septin cytoskeletons, and of the polarity establishment proteins. We propose that Sec3p is a spatial landmark defining sites of exocytosis. Polarized secretion would result from the coupling of actin-dependent vesicle targeting with Sec3p-dependent establishment of the vesicle fusion site.
Polarographic and electrochemical studies of some aromatic nitro compounds: Part VIII. Effects of solvents and surfactants on current–voltage curves obtained with DC and differential pulse polarography

Differential pulse polarography (DPP) is an excellent analytical method, but cannot be recommended for applications in the initial stages of mechanistic studies. Its application is also questionable in the analysis of samples containing varying concentrations of an organic cosolvent or of surface active compounds. The effect on limiting currents obtained by DC polarography and on peak currents obtained by DPP was demonstrated for reductions of various nitrobenzene derivatives. The similarity of changes in current for various nitrobenzenes enables the exclusion of the formation of adducts or micelles as the predominant effect. The decrease of the limiting currents in all cases is much smaller than the decrease of DPP peak currents, due to strong effects of the surfactants on the kinetics of electroreduction. For the analysis of natural products or of solutions containing varying amounts of organic cosolvent, the measurement of the DC polarographic limiting current is preferred. An addition of 30% ethanol minimizes the effects of the varying concentration of surfactant on both DC polarographic limiting and DPP peak currents.
Effects of Different Mediational Instructions and Sex of Subject on Paired-Associate Learning of Concrete Nouns.

Summary.-The present investigation compared the relative effectiveness of four differing instrucdonal sets on the paired-associate acquisition of concrete nouns. Possible sex differences were also examined. The instructional sets included standard paired-associate instructions (Minimal instructions), Rote Rehearsal, Verbal Mediation (requiring that S use a sentence or phrase containing both members of a given pair) and Visual Imagery Mediation (requiring that S create an imagined scene depicting both objects which the words of the pair represented). Consistent with previous findings, acquisition was greatly facilitated under Visual Imagery Mediation. Discrepant with past findings, however, performance under Verbal Mediation, although slightly superior to performance under the standard and rehearsal sets, was significantly inferior to performance under imagery instructions. Sex of S was not significantly related to performance.
Main Memory Evaluation of Monitoring Queries Over Moving Objects

In this paper we evaluate several in-memory algorithms for efficient and scalable processing of continuous range queries over collections of moving objects. Constant updates to the index are avoided by query indexing. No constraints are imposed on the speed or path of moving objects or fraction of objects that move at any moment in time. We present a detailed analysis of a grid approach which shows the best results for both skewed and uniform data. A sorting based optimization is developed for significantly improving the cache hit-rate. Experimental evaluation establishes that indexing queries using the grid index yields orders of magnitude better performance than other index structures such as R*-trees.
Embedding off-the-shelf filter in PDMS chip for microbe sampling

Filtration for microfluidic sample-collection devices is desirable for sample selection, concentration, preprocessing, and manipulation, but microfabricating the required sub-micrometer structures is an elaborate process. This article presents a simple method to integrate filters in polydimethylsiloxane (PDMS) devices to sample microorganisms in aqueous environments. An off-the-shelf membrane filter with 0.22-μm pores was embedded in a PDMS layer and sequentially bound with other PDMS channel layers. No leakage was observed during filtration. This device was validated by concentrating a large amount of biomass, from 15 × 107 to 3 × 108 cells/ml of cyanobacterium Synechocystis in simulated sample water with consistent performance across devices. The major advantages of this method are low cost, simple design, straightforward fabrication, and robust performance, enabling wide-utility of chip-based devices for field-deployable operations in environmental microbiology.
Population Regulation in Quill Mites (Acarina: Syringophilidae)

The wing quills of the House Sparrow (Passer domesticus L.) may host as many as three species of quill mites, suggesting ecological differences in the quill mite habitat. Detailed investigation of a single species of quill mite, Syringopbiloidus minor (Berl.) reveals adaptations that maximize mite success within the confines of the feather calmus, and suggests a mechanism that allows partitioning of the wing by two or more different sized quill mite species.
Scalar and Parallel Optimized Implementation of the Direct Simulation Monte Carlo Method

This paper describes a new concept for the implementation of the direct simulation Monte Carlo (DSMC) method. It uses a localized data structure based on a computational cell to achieve high performance, especially on workstation processors, which can also be used in parallel. Since the data structure makes it possible to freely assign any cell to any processor, a domain decomposition can be found with equal calculation load on each processor while maintaining minimal communication among the nodes. Further, the new implementation strictly separates physical modeling, geometrical issues, and organizational tasks to achieve high maintainability and to simplify future enhancements. Three example flow configurations are calculated with the new implementation to demonstrate its generality and performance. They include a flow through a diverging channel using an adapted unstructured triangulated grid, a flow around a planetary probe, and an internal flow in a contactor used in plasma physics. The results are validated either by comparison with results obtained from other simulations or by comparison with experimental data. High performance on an IBM SP2 system is achieved if problem size and number of parallel processors are adapted accordingly. On 400 nodes, DSMC calculations with more than 100 million particles are possible.
A schema matching system for on-the-fly autonomous data integration

Conventional schema matching systems usually choose a randomly ordered set of simple matchers and subsequently combine their individual scores with the help of a composite function ignoring the properties of the individual matchers and disregarding the context of the application of the matchers and therefore, culminate counterintuitive scores, improper matches, wasteful and counterproductive computations. Moreover, as users can hardly validate the processing accuracy until the computation is complete, matching efficiency and quality assurance play a crucial role in autonomous systems. In this paper, we propose a new method, OntoMatch, for schema matching that can avoid wasteful computation by a prudent and objective selection of the ordering of a subset of useful matchers and consequently improves the matching efficiency and accuracy. Experimental results corroborate that successive applications of the simple matchers in OntoMatch monotonically improve the matching score.
Lagrange Duality Theory for Convex Control Problems

The Lagrange dual of control problems with linear dynamics, convex cost and convex inequality state and control constraints is analyzed. If an interior point assumption is satisfied, then the existence of a solution to the dual problem is proved; if there exists a solution to the primal problem, then a complementary slackness condition is satisfied. A necessary and sufficient condition for feasible solutions in the primal and dual problems to be optimal is also given. The dual variables p and v corresponding to the system dynamics and state constraints are proved to be of bounded variation while the multiplier corresponding to the control constraints is proved to lie in $\mathcal{L}^1 $. Finally, a control and state minimum principle is proved. If the cost function is differentiable and the state constraints have two derivatives, then the state minimum principle implies that a linear combination of p and v satisfy the conventional adjoint condition for state constrained control problems.
Digital Color Image Compression In A Perceptual Space

A nonlinear mathematical model for the human visual system (HVS) is selected as a preprocessing stage for monochrome and color digital image compression. Rate distortion curves and derived power spectra are used to develop coding algorithms in the preprocessed "perceptual space." Black and white image compressions down to .1 bit per pixel are obtained. In addition, color images are compressed to 1 bit per pixel (1/3 bit per pixel per color) with less than 1% mean square error and no visible degradations. Minor distor-tions are incurred with compressions down to 1/4 bit per pixel (1/12 bit per pixel per color). Thus, it appears that the perceptual power spectrum coding technique "puts' the noise where one can not see it. The result is bit rates up to an order of magnitude lower than those previously obtained with comparable quality.© (1978) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Maximum weight independent set in trees

Computing a maximum independent set, weighted or unweighted, isNP-hard for general as well as planar graphs. However, polynomial time algorithms do exist for solving this problem on special classes of graphs. In this paper we present an efficient algorithm for computing a maximum weight independent set in trees. A divide and conquer approach based on centroid decomposition of trees is used to compute a maximum weight independent set withinO(n logn) time, wheren is the number of vertices in the tree. We introduce a notion of analternating tree which is crucial in obtaining a new independent set from the previous one.
Discrete simultaneous perturbation stochastic approximation for resource allocation in public health

In this paper, we consider the application of discrete simultaneous perturbation stochastic approximation (DSPSA) towards developing optimal public health strategies for containing the spread of influenza given limited societal resources. We use DSPSA to do the simulation based optimization to solve the optimal intervention method for H1N1 to achieve the minimal loss to the economy. The loss to the economy includes the cost related to the interventions and the cost induced by people infections. Based on open source software for intervention strategies (FluTE) we use DSPSA to determine the optimal intervention strategy instead of just doing sensitivity analysis on the effect of each intervention method.
Alloying aluminum with magnesium for ductility at warm temperatures (25 to 250°C)

Solute additions generally increase flow stress and decrease ductility. However, in an earlier study which compared the tensile behavior of a commercial Al-4 pct Mg alloy (5182-0) relative to pure aluminum, the commercial alloy exhibited increases in both strength and ductility at elevated temperatures (<250°C). To more fully understand this unexpected behavior, a series of high purity Al-Mg alloys (0 to 6 wt pct) were tested over the same range of temperatures (25 to 250°C) and initial strain rates (10-4 to 10-1 s-1) as in the earlier study. At ambient temperature the Mg solutes decreased elongation while increasing flow stress, but as the temperature was increased to 250°C the elongation increased with Mg content. This increase in ductility accompanied the linear increases in strain-rate sensitivity which occurred with increasing amounts of Mg. Stress relaxation tests indicated that Mg solutes increase the amount of dynamic recovery occurring at elevated temperatures. These results are explained on the basis of an increased amount of vacancies in the Al-Mg alloys relative to pure aluminum.
The Prediction, from Infancy, of Adult IQ and Achievement.

Abstract Young adults, originally tested as infants for their ability to process information as measured by selective attention to novelty (an operational definition of visual recognition memory), were revisited. A current estimate of IQ was obtained as well as a measure of academic achievement. Information processing ability at 6–12 months was predictive of adult IQ and of academic achievement with coefficients of .34 and .32, and coefficients corrected for unreliability of .59 and .53, respectively. The present results support and extend earlier studies indicating the continuity of intelligence from infancy to adolescence and illustrate the validity of early measures of recognition memory based on selective attention to novelty for the long‐term prediction of achievement.
Molecular and Mechanical Manipulation of Membrane Domains in Planar Supported Bilayers

Nano-membrane domains are hypothesized to play an integral role in many cell signaling pathways. Their transient nature and biocomplexity underlies a myriad of fundamental questions about lipid-lipid and lipid-protein interactions and their roles in cellular functions. As a result, there is a need for innovative approaches for understanding different biophysical aspects of membrane assemblies and their underlying, multiscale dynamics. Here, we integrate dynamic holographic optical trapping (HOT) and fluorescence imaging with fluorescence correlation spectroscopy (FCS) to characterize membrane domain nucleation in biomimetic planar supported bilayers. The dynamic HOT system allows for the creation of multiple traps from a single light source, each of which can be controlled individually in real time. Silica microspheres are being trapped into arbitrary patterns for system optimization. Receptor-bound microspheres associated with nano-domains in planar supported bilayers act as handles for dynamic HOT manipulation. Our hypothesis is that by trapping multiple microsphere-bound receptors, the associated heterogeneous lipid domains will nucleate a larger domain upon interaction in a manner that depends on the lipid type, cholesterol and protein content. Fluorescence imaging is used to visualize lipid domain formation, and subsequent lateral diffusion of lipid species will be measured with FCS as a function of trap-induced confinement. These results will ultimately lead to new insights into domain formation in membranes.
Grid-based matching for full-field large-area deformation measurement

Abstract Grid-based measurement can facilitate metrology and inspection of flexible electronics manufacturing. Multiple fundamental difficulties, however, arise in the large-area and full-field deformation measurement of deformable grid patterns including noise, occlusions, and artifacts. This paper addresses one of the key issues in deformation measurement: the registration and matching of deformed grid patterns. The emphasis is on accurate and robust periodicity tracing registration and constellation matching algorithms for grid pattern fidelity. The registration algorithm uses deviation metrics in deformed grids to estimate global translation, rotation and scaling; the matching algorithm uses the constellation reference grid to mine buried deformed point patterns. Using synthetic data, the validity of the registration algorithm is proved by registering noisy deformed grid patterns with various distortion scales and transformations; the validity of the matching algorithm is proved by matching deformed grid point patterns with various distortion scales, extra point rates and missing point rates. Compared to established non-rigid registration and point pattern matching algorithms, our algorithms demonstrate higher speed, sub-pixel accuracy and robustness in the matching of highly-deformed and noisy grids.
Computerized sociometric marketing: Advances and prospects

The prospects for marketing research and marketing programs that emphasize social influences on consumer behavior have been signficantly improved by recent methodological advances, particularly the development of powerful computer software. Three valuable approaches are linked pair research, computerized sociometry, and computer simulation of theories. Examples of each of these show both that real progress has been achieved and that opportunities exist for new and profitable computer applications.
Sources of Conflict in Southern Africa, c. 1800–30: The ‘Mfecane’ Reconsidered*

The so-called ‘mfecane’ has been explained in many ways by historians, but never adequately. Julian Cobbing has absolved the Zulu of culpability for ongoing regional conflicts, but his work is severely flawed in its use of evidence. Cobbing is incorrect to argue that the Delagoa Bay slave trade existed on a large scale prior to the disruptions beginning in 1817, and European slaving therefore cannot have been a root cause of political turmoil and change, as he claims. Cobbing correctly identifies European-sponsored slave-raiding as a major cause of violence across the north-eastern Cape Frontier, but his accusations of missionary involvement are false. Jeff Guy's interpretation of the rise of the Zulu kingdom based on environmental factors is inadequate because he examined only stock-keeping and not arable land use, which led him to false conclusions about demography and politics. In this paper I argue that the socio-political changes and associated demographic turmoil and violence of the early nineteenth century in southern Africa were the result of a complex interaction between factors governed by the physical environment and local patterns of economic and political organization. Increasing inequalities within and between societies coupled with a series of environmental crises transformed long-standing competition over natural resources and trade in south-eastern Africa into violent struggles.
Computed Tomography of a Traumatic Hepatic Arterial Pseudoaneurysm

We report a case of trauma causing the formation of a pseudoaneurysm of the proper hepatic artery. The preoperative computed tomographic (CT) finding of decreased enhancement of the left lobe of the liver was suggestive of ischemia or infarct secondary to hepatic arterial injury. A proper hepatic artery pseudoaneurysm was discovered on a follow-up postoperative CT. Retrospective review of the preoperative CT revealed the presence of a focal hematoma and an indistinct proper hepatic arterial segment at the site of the pseudoaneurysm. Although the pseudoaneurysm was not discovered intraoperatively, it was later confirmed by angiography and duplex ultrasound. The patient demonstrated extensive necrosis in the left lobe of the liver on the follow-up CT. The nature of the liver perfusion abnormalities that led to these findings is discussed.
Bayesian Multivariate Poisson Regression for Models of Injury Count, by Severity

In practice, crash and injury counts are modeled by using a single equation or a series of independently specified equations, which may neglect shared information in unobserved error terms, reduce efficiency in parameter estimates, and lead to biases in sample databases. This paper offers a multivariate Poisson specification that simultaneously models injuries by severity. Parameter estimation is performed within the Bayesian paradigm with a Gibbs sampler for crashes on Washington State highways. Parameter estimates and goodness-of-fit measures are compared with a series of independent Poisson equations, and a cost-benefit analysis of a 10-mph speed limit change is provided as an example application.
Relationship between stomatal conductance and light intensity in leaves of Zea mays L., derived from experiments using the mesophyll as shade.

Attached leaves of Zea mays were illuminated with monochromatic light, with either the upper or the lower epidermis facing the light source. The mesophyll absorbed between 99.5 and 99.6% of the red or blue light used. An inversion of the light direction therefore caused a 200- to 250-fold change in the quantum flux into each epidermis. This variation in quantum flux did not affect stomatal conductance. Stomatal conductance was however correlated with intercellular CO2 concentration, ci, and the relationship between stomatal conductance and ci appeared also to remain the same if changes in ci were brought about by changes in atmospheric CO2 concentration instead of light. A close inspection of the data showed that stomata of the upper (adaxial) epidermis exhibited a small increase in conductance (<0.1 cm s-1) in response to blue light that was superimposed on the dominating response to ci.
Spontaneously broken e-μ-τ symmetry and rare τ decays☆

Abstract Suppose that all differences between the leptons e, μ and τ arise from spontaneous symmetry breaking. Implementation of this idea in the standard gauge model leads to conservation of multiplicative rather than additive lepton number. The consequences of this are analysed.
Migration and homing of lymphocytes to lymphoid and synovial tissues in proteoglycan–induced murine arthritis

Objective. To describe the migration and homing of labeled donor lymphocytes to the lymphoid organs and synovial tissues of host animals, during the development of cartilage proteoglycan (PG)—induced arthritis adoptively transferred to syngeneic BALB/c mice. Methods. Lymphocytes from either nonarthritic or arthritic donor animals were labeled with either fluorescent or radioactive cell linkers (PKH–GL) and injected into syngeneic, immunosuppressed mice. The homing patterns of donor lymphocytes following the injection of labeled cells were studied by fluorescence microscopy and by measurement of radioactivity in tissue samples. Results. Lymphocytes from arthritic donors retained their ability to transfer the disease after labeling. In the lymphoid organs, arthritic and nonarthritic donor lymphocytes exhibited similar homing patterns, although remarkable differences were found in the number of homing cells derived from nonarthritic and arthritic donors. However, labeled cells only from arthritic animals migrated to the synovial tissue of the recipient mice, and their appearance was associated with the onset of arthritis. Conclusion. Lymphocytes from mice with PG–induced arthritis, in contrast to lymphocytes from nonarthritic donors, exhibit preferential homing to the synovial tissue of the host. Adoptive transfer of arthritis is linked to the appearance of these cells in the synovium.
Experimental RNA evolution

Abstract The recent ability to select functional RNA molecules through combinatorial chemistry has ignited exobiological research by offering a set of tools for testing early theories of RNA evolution without the need for organisms. This process can retrieve molecules present in as few as one in 1 × 10 15 sequences, which suggests that careful design may allow ‘resuscitation' of active RNA molecules that have been ‘extinct' for over three billion years, if they ever ‘lived' at all. These experiments now provide a wonderful setting for exploring the basic process of evolution at its most fundamental level – a single molecule – as well as providing a window onto the set of building blocks and constraints that would have defined many events in prebiotic evolution.
Mechanics and optics of stretchable elastomeric microlens array for artificial compound eye camera

Compound eye-inspired imaging devices can find vast applications due to their remarkable imaging characteristics, such as extremely large field of view angle, low aberrations, high acuity to motion, and infinite depth of field. Recently, researchers have successfully developed a digital camera that resembles the structure and functions of apposition compound eyes of arthropod, by combining an elastic array of microlenses with a stretchable array of photodetectors in their planar form and then transforming into a hemispherical shape. Designing an elastomeric microlens array that can be mechanically stretched to very large extent without deteriorating the optical performance is critical to this development. In this study, mechanics and optics of the stretchable microlens array, in which each hemispherical microlens sits on top of a supporting post connected to a base membrane, are studied. The results show that proper designs of the microlenses, supporting posts and base membrane are critically important to meet both mechanical and optical requirements simultaneously. This study can have important implications in not only the design of artificial compound eye cameras, but also other developments that require stretchable optical elements.
Travelling wave solutions for combined and double combined sine–cosine-Gordon equations by the variable separated ODE method

Abstract A combined sine–cosine-Gordon and a double combined sine–cosine-Gordon equations, that combine the effects of sine and cosine, are investigated. The analysis rests mainly on the newly developed variable separated ODE method [Sirendaoreji, Sun Jiong, A direct method for solving sinh-Gordon type equation, Phys. Lett. A 298 (2002) 133–139]. Exact travelling wave solutions for the combined equations are formally derived by using this method. The work emphasizes the power of the method that can be used in problems of identical nonlinearities.
Laser processing of inconel 600 and surface structure

Abstract The results on laser shot peening of Inconel 600 are presented. A brief description of the physical processes involved in the pressure generation mechanism is given. Using an X-ray diffraction technique we show that the residual compressive stresses can be successfully induced in Inconel 600 with parameters of laser peening, which are close to that of 316L stainless steel. We found that the laser spot scanning of the surface during processing results in a system of column-like microstructure, which is tilted in the direction of scanning. The light reflected from this microstructure is predominantly scattered at angles which are different from the incidence angle. We revealed that the base material injected into the confining water due to laser ablation is transformed into spherical nanoparticles with diameter as small as 60 nm.
Settling into an Increasingly Hostile World: The Rapidly Closing “Recruitment Window” for Corals

Free space is necessary for larval recruitment in all marine benthic communities. Settling corals, with limited energy to invest in competitive interactions, are particularly vulnerable during settlement into well-developed coral reef communities. This situation may be exacerbated for corals settling into coral-depauperate reefs where succession in nursery microhabitats moves rapidly toward heterotrophic organisms inhospitable to settling corals. To study effects of benthic organisms (at millimeter to centimeter scales) on newly settled corals and their survivorship we deployed terra-cotta coral settlement plates at 10 m depth on the Mesoamerican Barrier Reef in Belize and monitored them for 38 mo. During the second and third years, annual recruitment rates declined by over 50% from the previous year. Invertebrate crusts (primarily sponges) were absent at the start of the experiment but increased in abundance annually from 39, 60, to 73% of the plate undersides by year three. Subsequently, substrates hospitable to coral recruitment, including crustose coralline algae, biofilmed terra-cotta and polychaete tubes, declined. With succession, substrates upon which spat settled shifted toward organisms inimical to survivorship. Over 50% of spat mortality was due to overgrowth by sponges alone. This result suggests that when a disturbance creates primary substrate a “recruitment window” for settling corals exists from approximately 9 to 14 mo following the disturbance. During the window, early-succession, facilitating species are most abundant. The window closes as organisms hostile to coral settlement and survivorship overgrow nursery microhabitats.
Hydrogen bonding. Part 73. IR, NMR, and ab initio molecular orbital study of N,N-dimethyl-1-adamantamine-hydrogen fluoride, a crystalline, H2O stable compound with a three-center N–H–F bond

Abstract N , N -dimethyl-1-adamantamine-hydrogen fluoride is not a tertiary ammonium salt. It is a highly crystalline molecular complex whose infrared spectrum demonstrates the presence of covalent type three-center N–H–F bonds. The compound is obtained from ethanol–water solution, and FT-NMR spectra indicate that it is stable in aqueous solution. An ab initio molecular orbital study of this and potentially similar tertiary amine–hydrogen fluoride complexes suggests a value of about −18 kcal mol −1 for the formation of N–H–F bond, and in addition predicts that secondary C–H⋯F hydrogens bonding by β-hydrogens of the amine may be present in such compounds.
Levels of Processing: Effects of Interference in Word Learning over Time:

Although much research has addressed the “levels-of-processing” perspective, critics continue to attack this formulation. The lack of an operational definition is frequently cited as a shortcoming of the perspective. Utilizing resistance to interference as a perspective from which to investigate “deep” and shallow” processing, an experiment was conducted with two follow-up tests to ascertain the effects of proactive and retroactive interference in immediate, intermediate, and long-term recall.
Measurement of a phase-shifting mask with the Mirau correlation microscope

We describe here an interference microscope, the Mirau correlation microscope, for examining a phase-shifting mask used in lithography. The accuracy of the phase measurements obtained was +/- 2 degrees (or equivalently +/- nm in height variations) at 577 nm wavelength, with a transverse resolution of the order of 0.4 micrometers . A transmission phase- shifting mask was examined. The amplitude image showed the locations of the bright (transmitting) and dark (chromium) regions of the mask while the phase shifts introduced by the mask were revealed by the phase image. Mask defects in the chromium regions and phase shifting errors in the transmitting regions could thus be readily identified.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Temperature dependence of relaxation times and the length scale of cooperative motion for glass-forming liquids

When considered in the framework of a dynamic scaling model, the length scale of cooperative motion of all glass-forming liquids appears to have a universal temperature dependence. This model also predicts relaxation times with a system-specific temperature dependence, as the product of the universal cooperative length scale raised to the sixth power and a non-universal thermally activated process. In the glassy state, the length scale for cooperative motion can become temperature-independent, so the model predicts relaxation times to have an Arrhenius temperature dependence. As expected by the model, the same activation energy is observed both above and below the glass transition. At sufficiently high temperatures the model ceases to apply to relaxation times, and the crossover to a high-T Arrhenius temperature dependence provides an experimental estimate of the caging temperature. We also report an approximate power law relation between the fragility index and the cooperative length scale at the glass transition.
Differential interactions of traditional and novel antiemetics with dopamine D2 and 5-hydroxytryptamine3 receptors.

The affinities of 11 drugs for both dopamine D2 and 5-hydroxytryptamine3 (5-HT3) receptor sites were determined in brain membranes. The five “traditional” antiemetics (chlorpromazine, prochlorperazine, droperidol, fluphenazine, and domperidone) displayed high affinity ( 10,000 nM) at the dopamine D2 receptor. Metoclopramide was unique among these agents in that it was similarly potent at dopamine D2 (240±60 n M) and 5-HT3 (120±30nM) receptors.
3470 Widespread circumferential mucosectomy in the porcine esophagus–a pilot study.

Endoscopic mucosal resection (EMR) is a procedure growing in significance as an alternative to surgery in the treatment of gastrointestinal mucosal lesions. Current EMR techniques are limited to lesions measuring less than 2 cm. Aim: To demonstrate that widespread circumferential mucosectomy up to 5 cm in length can be performed using a stripping method. Method: Eight, 60 kg anesthetized pigs were studied. The distal 5 cms of the esophagus was injected with 50% dextrose to create a lasting submucosal protective cushion. A strip of mucosa approximating 5 cm in length from the esophagogastric junction and 1 cm in width was marginated along its length and proximal end using a porcelain ball-tipped needle knife and prototype teflon backed monopolar scalpel (Olympus America, Inc., NY). The proximal end once undermined was grasped using forceps and stripped off the submucosal cushion in a distal direction. The distal end was then resected using a needle knife from a retroflexed position. This was repeated sequentially until the distal esophagus was circumferentially denuded of mucosa. Four pigs were sacrificed immediately after the procedure while two each of the remaining four animals were followed for two and four weeks. Result: Complete widespread circumferential mucosectomy was achieved in five animals with an average of four strips removed per pig. The average strip length was 5.5 cm(range 5-6 cm) and width 0.9 cm(range 0.6-1.2 cm). There were no procedural complications in the five animals. Mucosectomy was incomplete in the first two animals as the technique of mucosal stripping evolved with another animal experiencing a perforation early in this learning curve. The animals sacrificed immediately post-procedure showed histologically intact muscularis propria with some preservation of the submucosa and minimal associated edema and cautery injury. Repeat endoscopy of the surviving animals (4) showed healing with moderate (1) to tight (3) strictures at both two and four weeks. Conclusion: 1. Widespread circumferential esophageal mucosectomy can be performed endoscopically using a true stripping technique with preservation of the muscularis propria. 2. This technology has exciting potential clinical applications especially in the treatment of Barrett's esophagus. 3. The appropriate measures to prevent post-procedural stricture formation need to be further investigated and identified. (The Apollo Group: Sydney Chung, Peter Cotton, Christopher Gostout, Robert Hawes, Anthony Kalloo, Pankaj Pasricha, Thadeus Trus)
A Robust Approach to Categorical Data Analysis

Categorical data analysis is typically performed by fitting models to the observed counts in a contingency table using maximum likelihood. An inherent problem with maximum likelihood fits is their sensitivity to outlier cells, ones whose counts are not consistent with the presupposed model. Robust alternatives to maximum likelihood estimation, including least median of chi-squared residuals, least median of weighted squared residuals, and analogous methods using least trimmed functions, are proposed in this article. Equivariance and breakdown properties are discussed. Monte Carlo simulation results and three real examples are used to illustrate the properties of the estimators in practice. In particular, whereas the maximum likelihood estimates break down in the presence of outlying cells, the robust estimators do not as long as the contamination does not exceed the breakdown point. The proposed estimators perform similarly in the simulations; they are competitive with median polish when fitting independe...
Forty Hertz EEC Activity in Alzheimer's Type Dementia

EEG activity within the 40 Hz band was monitored during several tasks and during a non-task condition. Twelve right-handed subjects diagnosed as having Alzheimer's type dementia were studied. Results from this group were compared to a group of neurologically normal subjects of comparable age and IQ. Results show that while the normal group exhibited appropriate increases in 40 Hz activity during problem solving, the Alzheimer's type dementia group did not. In addition, the task appropriate lateralization of 40 Hz activity seen in the normal group was absent in the Alzheimer's type dementia group.
Nitrogen availability alters patterns of accumulation of heat stress-induced proteins in plants.

Mounting evidence suggests that heat-shock proteins (HSPs) play a vital role in enhancing survival at high temperature. There is, however, considerable variation in patterns of HSP production among species, and even among and within individuals of a species. It is not known why this variation exists and to what extent variation in HSPs among organisms might be related to differences in thermotolerance. One possibility is that production of HSPs confers costs and natural selection has worked towards optimizing the cost-to-benefits of HSP synthesis and accumulation. However, the costs of this production have not been determined. If HSP production confers significant nitrogen (N) costs, then we reasoned that plants grown under low-N conditions might accumulate less HSP than high-N plants. Furthermore, if HSPs are related to thermotolerance, then variation in HSPs induced by N (or other factors) might correlate with variation in thermotolerance, here measured as short-term effects of heat stress on net CO2 assimilation and photosystem II (PSII) function. To test these predictions, we grew individuals of a single variety of corn (Zea mays L.) under different N levels and then exposed the plants to acute heat stress. We found that: (1) high-N plants produced greater amounts of mitochondrial Hsp60 and chloroplastic Hsp24 per unit protein than their low-N counterparts; and (2) patterns of HSP production were related to PSII efficiency, as measured by Fv/Fm. Thus, our results indicate that N availability influences HSP production in higher plants suggesting that HSP production might be resource-limited, and that among other benefits, chloroplast HSPs (e.g., Hsp24) may in some way limit damage to PSII function during heat stress.
Direct Assessment of Course Outcomes: Strategies and Implementations for Mechanical Engineering Courses

The process of outcome assessment has become a major tool for evaluation of mechanical engineering programs as required by ABET. There are many ways to conduct assessment of course and program outcomes, but the direct assessment method is preferable to all other methods such as course grades and student surveys. Outcome assessment process of courses involves many steps: identifying the performance criteria, collecting the appropriate data, processing the data based on performance criteria, interpreting the results, and deciding the remediation or corrective actions to take. In this paper, strategies and implementations of direct assessment of course outcomes in the Department of Mechanical Engineering are described and discussed. Application and results of these direct assessments relevant to the Senior Capstone Design course in the Mechanical Engineering curricula are presented as an example. The methodology and implementation discussed in this paper may be beneficial to similar curricula at other institutions.© 2007 ASME