cssi/SciSciGPT-SciSciNet huggingface dataset:
Theory of an HF Chemical Laser

Abstract A theory is presented for an HF chemical laser employing both the hot and cold pumping reactions under c.w. conditions. Six vibration-rotation lines are considered to be lasing simultaneously. Aerodynamic control is incorporated to the extent that the flow is assumed to expand continuously, maintaining isothermal static conditions in the gas. Closed form solutions are obtained for the populations of the excited states. The results show the influence of the numerous parameters of the system on the specific power output, gain, and saturation. While significant fractions of the chemical energy available can be converted into energy in the laser beam, the theory suggests there remains room for substantial improvement. Comparisons are also discussed for situations where some of the lines are suppressed
Microscopic mechanisms of the shape memory effect in crosslinked polymers

In this work we perform coarse-grained molecular dynamics (MD) simulations to study the molecular origins of the thermal shape memory effect in crosslinked polymer materials. Thermal shape memory polymers (SMPs) are materials able to hold a deformed shape when cooled below the glass transition temperature, and subsequently recover the initial shape when heated. To use SMPs in various applications requires materials which reliably hold and recover their shapes; this has sparked recent synthesis work to create new SMP materials with optimized properties. Here we use coarse-grained MD simulations with different polymer chain models to determine which parameters affect relevant SMP behavior and to investigate the molecular mechanisms at the level of individual chains during temperature cycling. The simulations show how temperature-dependent chain mobility leads to shape memory polymer behavior. In particular, we demonstrate the importance of attractive monomer interactions in leading to ‘good’ SMP behavior. The results suggest promising routes for material development. Additionally, the mechanisms identified with the simple simulation model can be used to inform multi-scale models of SMP material behavior.
Concussive brain injury is associated with a prolonged accumulation of calcium: a 45Ca autoradiographic study.

In order to determine the extent and duration of calcium (Ca2+) flux following a lateral fluid percussion brain injury in the rat,45Ca autoradiography was used to study animals immediately, 6, 24 and 96 h after the insult. In addition, cell suspension studies were conducted to determine the extent of cellular flux of45Ca. Optical density and/or scintillation counting was utilized to provide a relative measure of45Ca accumulation within 20 different structures. The results indicated that in animals who exhibited no gross morphological damage,45Ca accumulation following injury was exhibited primarily within the ipsilateral cerebral cortex, dorsal hippocampus and striatum. This accumulation continued for several days returning to control levels by the 4th day after injury. In animals who sustained morphological damage, the contusion site exhibited a marked accumulation of45Ca which did not resolve spontaneously over the course of 4 days. We conclude from this work that Ca2+ flux is a major component of this experimental model of traumatic injury. Furthermore, that depending on the extent of cell damage, the accumulation of Ca2+ is regionally different. Finally, that even in an injury which by itself does not produce gross morphological tissue damage, accumulation of Ca2+ can continue for at least 48 h.
Perturbations with several independent parameters

In this paper we discuss the problem of determining a T-periodic solution x∗(·, λ) of the differential equation x = A(t)x + f(t, x, λ) + b(t), where the perturbation parameter λ is a vector in a parameter-space Rk. The customary approach assumes that λ = λ(ϵ), ϵ ϵ R. One then establishes the existence of an ϵ0 > 0 such that the differential equation has a T-periodic solution x∗(·, λ(ϵ)) for all ϵ satisfying 0 < ϵ < ϵ0. More specifically it is usually assumed that λ(ϵ) has the form λ(ϵ) = ϵλ0 where λ0 is a fixed vector in Rk. This means that attention is confined in the perturbation procedure to examining the dependence of x∗(·, λ) on λ as λ varies along a line segment terminating at the origin in the parameter-space Rk. The results established here generalize this previous work by allowing one to study the dependence of x∗(·, λ) on λ as λ varies through a “conical-horn” whose vertex rests at the origin in Rk. In the process an implicit-function formula is developed which is of some interest in its own right.
Dynamic Variable Speed Limit Strategies for Real-Time Crash Risk Reduction on Freeways

Recent research at the University of Central Florida involving crashes on I-4 in Orlando, Florida, has led to the creation of new statistical models capable of determining the crash risk on the freeway in real time. The potential benefits of variable speed limit (VSL) implementation for reducing the crash risk along the freeway at different loading scenarios was studied. VSL strategies were used in a networkwide attempt to reduce rear-end and lane-change crash risks where speed differences between upstream and downstream vehicles were high. The idea of homogeneous speed zones also was introduced in this study to determine the distance over which variable speed limits should be implemented from a station of interest. This idea is unique because it is the first time a dynamic distance has been considered for VSL implementation. This study shows that VSL is an effective crash prevention strategy when the freeway is operating in uncongested conditions. Specifically, in free-flow conditions and conditions appr...
Defining and addressing the risk of undesirable emergent properties

Emergent properties are an important consideration in the engineering of complex systems. Unfortunately, the possibility of undesirable emergent properties is not always assessed during systems engineering. However, the potential for adverse consequences related to undesirable emergent properties requires that undesirable emergent properties be evaluated and managed as risks. This paper discusses a taxonomy for characterizing emergent properties and how an organization may consider addressing undesirable emergent properties as risks throughout the systems engineering lifecycle.
Optimal time and frequency domain waveform design for target detection

Some marine mammals as well as bats are known to emit sophisticated waveforms while searching for objects or hunting prey. Some dolphins have been observed to change their sonar pulse depending on the environment. Incorporating these strategies into sonar waveform and receiver design has become an active area of research. In this paper, we explore the application of an optimal waveform design scheme recently given by Kay, to the detection of elastic objects. We examine the benefits of optimal waveform design versus transmitting a linear FM waveform, as well as performance loss suffered by assuming a point target. The optimization approach designs the magnitude spectrum of the transmit waveform and, accordingly, there is an unlimited number of "optimal" transmit waveforms with the same magnitude spectrum. We propose a time domain optimization criterion to obtain the transmit waveform with the optimal magnitude spectrum and the smallest possible duration, as well as the waveform with the optimal magnitude spectrum and the longest possible duration. The former waveform allows for higher ping rates, but necessarily has higher time domain peak power, while the latter waveform has lower time domain peak power and lower ping rates. A method to obtain waveforms that are a blend of these two extremes is also presented, allowing a smooth trade-off between ping rate and peak power.
Binding of lanthanide shift reagents to oxaziridines

Abstract The preferred binding site of tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-octane-4,6-dionato)ytterbium(III) (Yb(fod) 3 ) has been determined for the following oxaziridines: 2- tert -butyl-oxaziridine, trans -2- tert -butyl-3-(4-methylphenyl)-oxaziridine, trans -2-methyl-3-(4-methylphenyl)-oxaziridine, cis -2-methyl-3-(4-methylphenyl)-oxaziridine, 2-methyl-3,3-(3- tert -butyl-pentamethylene)-oxaziridine, and for the following model compounds: 3,3-dimethyl-1,2-epoxybutane, 1- tert -butylaziridine, and 2,2-dimethylaziridine. Computer refinement of the lanthanide-induced shift gradients was used to locate the lanthanide with respect to the heteroatoms of the oxaziridine. For unhindered oxaziridines, nitrogen appears to be the preferred coordination site. However, oxygen becomes the coordination site when the nitrogen or ring carbon bears bulky groups.
New method for characterizing the dynamic properties of electroviscoelastic materials

A direct method for determining the dynamic stiffness properties of electroviscoelastic materials is described. Electroviscoelastic materials (EVEMs) are characterized as having stiffness and damping properties that vary with frequency, temperature, and applied voltage. The test system described allows the direct measurement of the complex stiffness (shear modulus, loss factor) of EVEMs at varying voltages and temperatures. Design of the test apparatus incorporates a double-lap shear type refrigerated test fixture utilizing a laser vibrometer to measure the dynamic response of the moving mass subjected to a periodic chirp excitation. A refrigeration system controls the temperature of the moving mass, stationary masses, and test specimens in order to study the effect of temperature on dynamic material property behavior. The test system is first validated by measuring the dynamic properties of a known viscoelastic damping material as function of frequency and temperature. Second the material properties of an EVEM are studied as a function of frequency only. The EVEM consists of poly (p-phenylenes) particles doped with FeCl3 suspended in a blended silicone gel, which reacts to an electric field. Techniques addressing data reduction, mechanical compliance, and electrical insulation are discussed.
A bifurcation approach to understanding instabilities in gas-fluidized beds using a single phase compressible flow model

It has been shown that the equations of motion and continuity for the particles in a fluidized bed can be related to those of a compressible fluid acted upon by a density-dependent force. In the previous work on the compressible flow equations, the solution structure of fully developed plane (one-dimensional) waves was computed. It was shown that the plane waves can lose stability in the lateral direction. In this work we study the two-dimensional solutions which reveal that bubble-like solutions can evolve both from the plane waves as well as from the uniform state. A representative value of the lateral wavenumber is chosen and the global bifurcation diagram is explored, which consists of a number of distinct one- and two-dimensional branches. The existence of mixed mode and double humped solutions is demonstrated and transient simulations are used to examine the mechanism of density wave development and coalescence.
Establishment and initial characterization of continuous in vitro cultures of bovine T lymphocytes.

Abstract Utilizing human recombinant interleukin 2 (HrIL-2) in combination with several mitogens, continuously growing cultures of bovine lymphocytes have been established. Continuous presence of HrIL-2 is required to maintain the growth of these cultures but a requirement for continued presence of mitogen seems variable. Cloned lines have been derived from these cultures by limiting dilution and outgrowth in the presence of mitomvcin C treated bulk cells. Cell surface phenotype analysis indicates that all of these cultures and cloned lines are of the T cell lineage. Functional analysis indicated that some of these cultured cells are cytolytically active in lectin mediated assays whereas others are not. Utilization of this technology for the growth and characterization of bovine T cells will undoubtedly contribute to an enhanced understanding of the bovine immune response mechanisms.
Effect of combustion chamber insulation on the performance of a low heat rejection diesel engine with exhaust heat recovery

Abstract A computer simulation of the turbocharged turbocompound diesel engine system is used to study the effect of combustion chamber insulation on the performance of low heat rejection system configurations with exhaust heat recovery. The analysis is carried out for zirconia coatings of various thickness applied on the cylinder head and piston. It is found that an intercooled turbocompound engine derives a modest thermal efficiency benefit from insulation, e.g. 4.3% improvement at a 60% reduction in heat loss. The addition of Rankine compounding can improve the thermal efficiency of the turbocompound engine by 10–14%, depending on the level of insulation and the system configuration. Furthermore, Rankine compounding can make the otherwise inferior performance of a non-intercooled engine match the performance of an intercooled engine. Finally, use of an insulating material of low conductivity and low heat capacity can increase the thermal efficiency benefits, but at the expense of increased component thermal loading.
Characterization of muscarinic receptors mediating the contraction of the urinary detrusor muscle in cynomolgus monkeys and guinea pigs

Abstract We have characterized in vitro the muscarinic receptors mediating the contraction of the detrusor muscle in Cynomolgus monkeys and guinea pigs using carbachol as the agonist and 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP, M3-selective), methoctramine (M2-selective) and pirenzepine (M1-selective) as the antagonists. Carbachol induced a concentration-dependent contraction of the detrusor muscle of monkey and guinea pig yielding similar pD2 values of 6.67 ± 0.03 (n = 50) and 6.77 ± 0.06 (n = 36), respectively. In the detrusor muscle of Cynomolgus monkey, all antagonists produced a concentration-dependent inhibition of carbachol-induced contractions, without decreasing the maximal response. Schild plot analysis yielded slopes not different from unity for all antagonists. The order of antagonist potency was: 4-DAMP (pA2 = 8.96) > pirenzepine (pA2 = 6.66) > methoctramine (pA2 = 6.03), suggesting that M3 receptors have a dominant role in mediating detrusor contraction. In the detrusor muscle of the guinea pig, 4-DAMP and pirenzepine, but not methoctramine, produced a concentration-dependent inhibition of the carbachol-induced contractions, without decreasing the maximal response. Schild plot analysis yielded a slope not different from unity for 4-DAMP and pirenzepine. 4-DAMP (pA2 = 9.07) had a higher potency than pirenzepine (pA2 = 6.66), a finding consistent with previously published data. The present study shows that in Cynomolgus monkey stimulation of the M3 subtype is dominant in mediating detrusor contraction upon carbachol stimulation.
Dual-responsive polymer-coated iron oxide nanoparticles for drug delivery and imaging applications.

Abstract We reported the synthesis and characterization of dual-responsive poly( N -isopropylacrylamide-acrylamide-chitosan) (PAC)-coated magnetic nanoparticles (MNPs) for controlled and targeted drug delivery and imaging applications. The PAC-MNPs size was about 150 nm with 70% iron mass content and excellent superparamagnetic properties. PAC-MNPs loaded with anti-cancer drug doxorubicin showed dual-responsive drug release characteristics with the maximum release of drugs at 40 °C (∼78%) than at 37 °C (∼33%) and at pH of 6 (∼55%) than at pH of 7.4 (∼28%) after 21 days. Further, the conjugation of prostate cancer-specific R11 peptides increased the uptake of PAC-MNPs by prostate cancer PC3 cells. The dose-dependent cellular uptake of the nanoparticles was also significantly increased with the presence of 1.3 T magnetic field. The nanoparticles demonstrated cytocompatibility up to concentrations of 500 μg/ml when incubated over a period of 24 h with human dermal fibroblasts and normal prostate epithelial cells. Finally, pharmacokinetic studies indicated that doxorubicin-loaded PAC-MNPs caused significant prostate cancer cell death at 40 °C than at 37 °C, thereby confirming the temperature-dependent drug release kinetics and in vitro therapeutic efficacy. Future evaluation of in vivo therapeutic efficacy of targeted image-guided cancer therapy using R11-PAC-MNPs will reinforce a significant impact of the multifunctional PAC-MNPs on the future drug delivery systems.
Concepts needed to understand potential health effects of chronic low-level radiation exposures: Role of adult stem cells and modulated cell–cell communication

Abstract To understand the extremely relevant, but complex, process of potential low-level ionizing radiation-induced health effects, particularly, cancer, both research-derived factual results and theoretical concepts must be generated and tested. To date, due to the difficulties of (a) generating epidemiological statistically rigorous and unambiguous data at extremely low levels; (b) deriving any mechanistic understanding from epidemiological data; (c) doing enough animal experiments due to cost and even relevancy of results to human beings; (d) using dubious molecular, biochemical, cellular in vitro assays, due to limitations, artifacts and misinterpretation of results; and (e) potently lack of appropriate paradigms and concepts needed to interpret results of chronic low-level exposures, the usual default tactic to assume extrapolation down from high-level exposures, using a non-threshold, linear model seems to defy facts and concepts that are known about carcinogenesis to date. The objective of this short analysis is to point out that several important concepts, namely, the role of adult stem cells as the “target” cells for carcinogenesis, the role of cell–cell communication, and oxidative stress as an intra-cellular signal transducer must be considered in the risk assessment of chronic low-level radiation exposure. In fact, the relatively new concepts of the “adaptive response,” the “bystander effects” and “genomic instability” must be carefully integrated with the stem cell, cell–cell communication and oxidative stress-signaling concepts.
α-Amylase gene transcription in tissues of normal dog

We studied the distribution of alpha-amylase mRNA in normal dog tissues by northern blotting (NB) and reverse transcription-polymerase chain reaction (RT-PCR) with human pancreatic (AMY2) and salivary (AMY1) alpha-amylase cDNA-specific primers. Analysis of poly(A+) RNA from various normal tissues by NB indicated the presence of detectable levels of alpha-amylase mRNA transcripts only in pancreas. Dot-blot analysis of DNA amplified with primers common to both (human) isoamylase mRNAs showed presence of alpha-amylase gene transcripts not only in pancreas but also in liver, small intestine, large intestine and fallopian tube. Traces of amylase gene transcripts were also observed in ovary, uterus and lung. Interestingly, amylase transcripts were not detectable in the parotid gland by NB or RT-PCR. We have also localized alpha-amylase mRNA transcripts to dog pancreas by in situ transcription and in situ hybridization. Our results suggest that there is high degree of homology between the alpha-amylase mRNA sequences in dog and human at least in the exon 3-4 regions of the human gene.
Snell’s Law and the Calculus of Variations

It is shown that the Weierstrass–Erdmann corner conditions cannot be used to derive Snell’s law. Hilbert’s theory of the invariant integral in a field of extremals must be used instead.
Identification of urinary m-hydroxyphenylhydracrylic acid by gas chromatography-mass spectrometry.

β-(m-Hydroxyphenyl)hydracrylic acid has been identified in human urine by gas chromatography, high and low reso ution mass spectrometry, and proton nuclear magnetic resonance spectroscopy. A rapid and conclusive method is presented for the identification of this acid as its methyl ester and/or its methyl ester trimethylsilyl ether derivative by combined gas chromatography-mass spectrometry.
A combined experimental-numerical approach for elasto-plastic fracture of individual grain boundaries

Abstract The parameters for a crystal plasticity finite element constitutive law were calibrated for the aluminum–lithium alloy 2198 using micro-column compression testing on single crystalline volumes. The calibrated material model was applied to simulations of micro-cantilever deflection tests designed for micro-fracture experiments on single grain boundaries. It was shown that the load–displacement response and the local deformation of the grains, which was measured by digital image correlation, were predicted by the simulations. The fracture properties of individual grain boundaries were then determined in terms of a traction–separation-law associated with a cohesive zone. This combination of experiments and crystal plasticity finite element simulations allows the investigation of the fracture behavior of individual grain boundaries in plastically deforming metals.
Effect of Force-Feeding Diets Containing Varying Amounts of Lysine on Plasma Free Amino Acids in Laying Hens

Effects of force-feeding in contrast to ad libitum-feeding diets containing 0.35, 0.50, 0.65 and 0.80% lysine on plasma free amino acids were investigated in laying hens. The feed intake and body weight gain of hens fed ad libitum were less than those in hens force-fed: this was more prominent in hens fed low-lysine diets. The concentrations of plasma arginine, histidine, lysine, methionine, phenylalanine, valine, alanine, glutamic acid, proline, serine and tyrosine were greater in hens fed ad libitum while plasma threonine, asparagine plus glutamine, ammonia and uric acid were greater in hens force-fed. Plasma lysine was increased slowly by increases of dietary lysine from 0.35 to 0.65%, but rapidly from 0.65 to 0.80%. The concentrations of plasma leucine, phenylalanine, threonine, half-cystine, taurine and uric acid were greater in hens fed a low-lysine diet (0.35%) than in hens fed a high-lysine diet (0.80%). The plasma ratio of essential to non-essential amino acids was decreased when dietary lysine was increased from 0.35 to 0.50% and 0.50 to 0.65%. These results indicated that force-feeding apparently increased the catabolic rate of dietary protein. Plasma free lysine changed in response to the dietary lysine level in laying hens.
Polyhalo-organometallic and -organometalloidal compounds XII. The reaction of triphenylsilyllithium with hexafluorobenzene

Abstract The reaction of triphenylsilyllithium with an excess of hexafluorobenzene at low temperatures gave hexaphenyldisilane [compound (II)] and 1,4-bis(triphenylsilyl)tetrafluorobenzene [compound (III)] instead of the expected (pentafluorophenyl)triphenylsilane [compound (I)]. In an attempt to account for the formation of these products, the reactions of triphenylsilyllithium with certain organosilicon-substituted polyfluorobenzenes were investigated and are described. In contrast to the above reaction, triphenylsilyllithium reacted with hexachlorobenzene via halogen-metal exchange to give pentachlorophenyllithium and hexaphenyldisilane.
A comparative light and electron microscopic study of rabies and hart park virus encephalitis

Abstract Hart Park virus and rabiesvirus both produce a fatal encephalitis after intracerebral inoeulation into newborn mice. Hart Park murine encephalitis has a more rapid onset than rabies murine encephalitis. By light microscopy Hart Park encephalitis is characterized by a diffuse necrosis of neurons and mild neutrophilie infiltrate, whereas rabies is characterized by many cytoplasmic inclusions (Negri bodies) within neurons and marked parivascular cuffing by mononuclear cells. Electron microscopic examination of infected mouse brain revealed that Hart Park virus and rabiesvirus both “bud” in bullet-shaped particles from cell membranes of neurons and glial cells. However, rabiesvirus, unlike Hart Park, develops in association with retienlo-granular cytoplasmie viral matrices. Because of their morphologic similarities, rabiesvirus and Hart Park virus are included among the newly formed rhabdovirus group.
Milling contour error control using multilevel fuzzy controller

Machining contour error plays important roles in product quality. This paper presents an implementation of multilevel fuzzy controller in controlling contour errors while maintaining the desired feed rate of milling processes. The orthogonal global task frame was used to transform the tool positions from the Cartesian coordinate system to the curvilinear coordinate system. Contour error and tracking lag error calculated from the curvilinear coordinate system were used by the multilevel fuzzy controller to drive the machining axis on the Mazak VQC-15/40 vertical machining center. The contour error of the machined work piece measured by the coordinate measuring machine showed that the contour error were significantly reduced and the feed rate were regulated at the desired speed.
Cortical blindness and occipital lobe seizures induced by cis-platinum

Three patients developed occipital lobe seizures as a manifestation of diaminodichloro platinum (DDP) toxicity. They were characterized in two patients by cortical blindness, ictal nystagmus and a confusional state. The third patient had visual hallucinations followed by grand mal seizures. All the abnormalities in these patients responded to anticonvulsant therapy.
Supramolecular Triads Formed by Axial Coordination of Fullerene to Covalently Linked Zinc Porphyrin−Ferrocene(s): Design, Syntheses, Electrochemistry, and Photochemistry

Supramolecular triads have been constructed by using covalently linked zinc porphyrin−ferrocene(s) dyads, self-assembled via axial coordination to either pyridine- or imidazole-appended fulleropyrrolidine. These triads were characterized by optical absorption, computational, and electrochemical methods. The calculated binding constants (K) revealed stable complexation and suggested the existence of intermolecular interactions between the ferrocene and fullerene entities. Accordingly, the optimized geometry obtained by ab initio B3LYP/3-21G(*) methods revealed closely spaced ferrocene and fullerene entities in the studied triads. Photoinduced charge-separation and charge-recombination processes were examined in the dyads and triads by means of time-resolved transient absorption and fluorescence lifetime measurements. In the case of zinc porphyrin−ferrocene(s) dyads, upon photoexcitation, efficient (ΦCS = 0.98) to moderate (ΦCS = 0.54) amounts of electron transfer from the ferrocene to the singlet excited z...
Factor Price Stabilization and the Competitive Firm

This paper investigates the effects of factor price stabilization on production decisions of the competitive firm with ex post production flexibility. Factor price stabilization is achieved through changes in the guaranteed minimum price and the imposed maximum price. For the risk-averse firm, the effect of factor price stabilization, through a mean-preserving contraction, on capital crucially depends on whether capital and the variable input are substitutes or complements as well as the observable characteristics of the variable input demand curve.
Once-per-step control of ankle-foot prosthesis push-off work reduces effort associated with balance during walking.

Background: Individuals with below-knee amputation have more difficulty balancing during walking, yet few studies have explored balance enhancement through active prosthesis control. We previously used a dynamical model to show that prosthetic ankle push-off work affects both sagittal and frontal plane dynamics, and that appropriate step-by-step control of push-off work can improve stability. We hypothesized that this approach could be applied to a robotic prosthesis to partially fulfill the active balance requirements of human walking, thereby reducing balance-related activity and associated effort for the person using the device. Methods: We conducted experiments on human participants (N = 10) with simulated amputation. Prosthetic ankle push-off work was varied on each step in ways expected to either stabilize, destabilize or have no effect on balance. Average ankle push-off work, known to affect effort, was kept constant across conditions. Stabilizing controllers commanded more push-off work on steps when the mediolateral velocity of the center of mass was lower than usual at the moment of contralateral heel strike. Destabilizing controllers enforced the opposite relationship, while a neutral controller maintained constant push-off work regardless of body state. A random disturbance to landing foot angle and a cognitive distraction task were applied, further challenging participants’ balance. We measured metabolic rate, foot placement kinematics, center of pressure kinematics, distraction task performance, and user preference in each condition. We expected the stabilizing controller to reduce active control of balance and balance-related effort for the user, improving user preference. Results: The best stabilizing controller lowered metabolic rate by 5.5% (p = 0.003) and 8.5% (p = 0.02), and step width variability by 10.0% (p = 0.009) and 10.7% (p = 0.03) compared to conditions with no control and destabilizing control, respectively. Participants tended to prefer stabilizing controllers. These effects were not due to differences in average push-off work, which was unchanged across conditions, or to average gait mechanics, which were also unchanged. Instead, benefits were derived from step-by-step adjustments to prosthesis behavior in response to variations in mediolateral velocity at heel strike. Conclusions: Once-per-step control of prosthetic ankle push-off work can reduce both active control of foot placement and balance-related metabolic energy use during walking.
Rising to the Challenge: Using Business-Oriented Case Studies in Software Engineering Education

Case studies are a common method for teaching professions such as law and business. At Miami University, we use case studies to teach software engineering by holding a "Senior Challenge" as part of our senior-level software engineering course. The goal is to give the students experience studying, analyzing, and proposing solutions to a real-life information-technology related business problem. The Challenge concludes with a presentation of their findings to a jury of industry professionals including some from the company that wrote the case. The Challenge is structured to teach the students how to analyze a business problem for business and technical objectives, how to describe and defend candidate solutions, and how to effectively present their findings both orally and in writing. This is a difficult project that provides students with experience working with real and significant information-technology problems and in understanding the business impact of their technical decisions
An intelligent system for design optimization of electromagnetic devices

An intelligent system for the design optimization of electromagnetic devices is presented. The system comprises a back-propagation neural network in conjunction with an optimizing Hopfield Net for performing search and optimization functions. An adaptive algorithm is used to improve the response of the system in a dynamic environment. Data can be input by an experienced designer in addition to a case generator from the finite element (FE) solutions. Optimal designs are obtained quickly once the artificial neural network (ANN) is trained with a variety of topologies. Results of implemented examples are provided to show the effectiveness of the proposed system. >
Contributions of ATP, GTP, and Redox State to Nutritional Stress Activation of the Bacillus subtilis σB Transcription Factor

The general stress regulon of Bacillus subtilis is induced by activation of the sigma(B) transcription factor. sigma(B) activation occurs when one of two phosphatases responds to physical or nutritional stress to activate a positive sigma(B) regulator by dephosphorylation. The signal that triggers the nutritional stress phosphatase (RsbP) is unknown; however, RsbP activation occurs under culture conditions (glucose/phosphate starvation, azide or decoyinine treatment) that reduce the cell's levels of ATP and/or GTP. Variances in nucleotide levels in these instances may be coincidental rather than causal. RsbP carries a domain (PAS) that in some regulatory systems can respond directly to changes in electron transport, proton motive force, or redox potential, changes that typically precede shifts in high-energy nucleotide levels. The current work uses Bacillus subtilis with mutations in the oxidative phosphorylation and purine nucleotide biosynthetic pathways in conjunction with metabolic inhibitors to better define the inducing signal for RsbP activation. The data argue that a drop in ATP, rather than changes in GTP, proton motive force, or redox state, is the key to triggering sigma(B) activation.
Clinical, microbiological and immunological characteristics of subjects with “refractory” periodontal disease

Abstract The aim of the present study was to analyze the relationship between attachment loss and clinical, microbiological, and immunological parameters in a group of 21 human subjects exhibiting poor response to previous periodontal therapy. All had been treated with periodontal surgery, tetracycline, and subsequent maintenance recalls to periodontists who, upon detection of disease progression, referred the subjects to our clinic. In our clinic, each subject received oral hygiene instruction and a thorough subgingival scaling and root planing utilizing as many appointments as necessary. Clinical indices, including gingival index, bleeding on probing, suppuration, plaque index, pocket depth, and duplicate measurements of attachment level from an acrylic stent, were collected at monthly intervals. Probing measurements were performed using the Florida Probe®. When significant attachment loss (0.8–1.2 mm) was detected in at least 1 site, a bacterial sample was taken from that site and from a comparably deep, but non-progressing, control site. Microbial samples were enumerated by darkfield microscopy, on selective and non-selective media, and by predominant cultivable technique. Blood samples were also collected to determine antibody levels against potential pathogens. There was no difference in the amount of plaque present in sites gaining or losing attachment, but losing sites exhibited more bleeding and suppuration. 20 of the 21 subjects were tested; of these, 17 exhibited elevated serum antibody against one or more of the following microorganisms: Actinobacillus actinomycetemcomitans, Bacteroides, gingivalis, and Eikenella corrodens. However, few, if any, of the “classical” pathogens were detected in the plaque samples obtained at the time progressive disease was diagnosed. The only exception was Streptococcus intermedius, which occurred in slightly higher numbers in active sites.
The role of cell surface recognition structures in the initiation of MHC-unrestricted ‘promiscuous’ killing by T cells

CD3+ T cells mediate relatively promiscuous patterns of major histocompatibility complex (MHC)-unrestricted target cell lysis following activation. Cell-cell contact between target and effector cells is essential in this form of cytotoxicity. Although the T-cell receptor (TCR)-CD3 molecular complex can transmit signals that initiate MHC unrestricted T-cell killing, recognition of targets by the TCR is not essential for this form of cytotoxicity. In this review by Dwain Thiele and Peter Lipsky, a model of the triggering of T cells to effect MHC-unrestricted cytotoxicity is proposed.
Retinole acid and glucocorticoids enhance the effect of 1,25‐dihydroxyvitamin D3 on bone γ‐carboxyglutamic acid protein synthesis by rat osteosarcoma cells

Two 1,25-dihydroxyvitamin D3-controlled parameters in the osteoblastlike osteosarcoma cell line ROS 17/2, bone gamma-carboxyglutamic acid-containing protein (BGP) and collagen synthesis, were measured after pretreatments with either retinoic acid (RA), or triamcinolone acetate (TRM). RA and TRM both caused double the expected increase in BGP secretion at 16 hr after treatment with 1,25-dihydroxyvitamin D3. Triamcinolone acetate concentrations of 10(-8) and 10(-9) M or 10(-6) M retinoic acid were effective in enhancing the 1,25-dihydroxyvitamin D3 stimulation of BGP secretion. Treatment with RA or TRM alone did not stimulate BGP secretion. RA alone had no effect on BGP secretion, while TRM inhibited BGP secretion. Collagen synthesis is inhibited by 1,25-dihydroxyvitamin D3. Neither retinoic acid nor triamcinolone acetate enhanced the 1,25-dihydroxyvitamin D3-mediated inhibition of collagen synthesis. Retinoic acid by itself inhibited collagen synthesis but did not change the 1,25 dihydroxyvitamin D3-mediated inhibition of collagen synthesis. Triamcinolone acetate by itself or together with 1,25-dihydroxyvitamin D3 increased collagen synthesis. We conclude that, although both triamcinolone acetate and retinoic acid increase the 1,25-dihydroxyvitamin D3 stimulation of BGP secretion by ROS 17/2 cells, they have different effects on the regulation of collagen production. Thus, although both hormones increase the 1,25-dihydroxyvitamin D3 receptor concentration in these cells, their actions are not mediated solely by this mechanism.
Progressive refinement for support vector machines

Support vector machines (SVMs) have good accuracy and generalization properties, but they tend to be slow to classify new examples. In contrast to previous work that aims to reduce the time required to fully classify all examples, we present a method that provides the best-possible classification given a specific amount of computational time. We construct two SVMs: a "full" SVM that is optimized for high accuracy, and an approximation SVM (via reduced-set or subset methods) that provides extremely fast, but less accurate, classifications. We apply the approximate SVM to the full data set, estimate the posterior probability that each classification is correct, and then use the full SVM to reclassify items in order of their likelihood of misclassification. Our experimental results show that this method rapidly achieves high accuracy, by selectively devoting resources (reclassification) only where needed. It also provides the first such progressive SVM solution that can be applied to multiclass problems.
Monitoring and characterization of component-based systems with global causality capture

Current software development techniques and tools lack the capability to characterize function call chains in multithreaded and distributed applications built upon component technologies like CORBA, COM and J2EE. The root cause is that causal linkage information necessary to trace end-to-end call chains is private to each vendor's runtime and often unavailable for logging or analysis. We propose and demonstrate a mechanism for maintaining and correlating global causality information of component-based applications, and using this information to expose and characterize function call chains and their associated behaviors in such multithreaded and distributed applications. Our approach relies on a global virtual tunnel facilitated by the instrumented stubs and skeletons. This tunnel maintains and correlates causal information throughout the end-to-end call chains spanning threads, processes and processors. As a result, monitoring data captured locally can be correlated and system-wide propagation of timing latency and CPU utilization becomes perceivable.
Limitations of community college benchmarking and benchmarks

This chapter distinguishes between benchmarks and benchmarking, describes a number of data and cultural limitations to benchmarking projects, and suggests that external demands for accountability are the dominant reason for growing interest in benchmarking among community colleges.
Hacking Radio History’s Data: Station Call Signs, Digitized Magazines, and Scaled Entity Search

This article uses scaled entity search (SES), a data mining technique and interpretive framework, to study the historically dynamic role of local radio broadcasters in the United States. The authors model the technique by searching for more than two thousand individual radio call letters and discussing the call signs with the highest number of page hits, with critical attention to the meaning of those results within the 1.6 million page digitized corpus of the Media History Digital Library. They also detail the strategies of one of the top-trending stations, WCCO Minneapolis, to distinguish itself in the broadcasting marketplace through the trade press. The authors conclude that WCCO’s emphasis on various aspects of the local market through facts and figures, constructions of local market identity, and relationships with sponsors instantiated a larger trend on the part of local broadcasters to position themselves favorably to advertisers and other industry participants.
Next Generation Valves: What Are We Looking for?∗

Transcatheter aortic valve replacement (TAVR) is an established treatment for severe symptomatic aortic stenosis patients who are not suitable or are at high risk for surgical aortic valve replacement (SAVR) [(1–3)][1]. Several ongoing studies are exploring its role in lower risk patients [(4)][2
Analogue multiplier using passive circuits and digital primitives with time‐mode signal representation

A new architecture to multiply signals with time-mode representations is proposed. The exponential relationship between voltage and time in an RC circuit is utilised to implement the time-mode logarithmic and exponential functions needed to realise a time-mode analogue of the translinear principle. The addition of time-mode variables is achieved through the natural progression of time equal to the sum of the input times. By combining these two techniques, an analogue multiplier can be implemented almost exclusively with passive circuits and digital primitives. Therefore, the circuit performance could benefit from CMOS scaling trends. The architecture is described, and simulation results are presented for an operational circuit implementing this approach.
Aging alters bone-fat reciprocity by shifting in vivo mesenchymal precursor cell fate towards an adipogenic lineage

Bone marrow derived mesenchymal progenitor cells (MPCs) play an important role in bone homeostasis. Age-related changes occur in bone resulting in a decrease in bone density and a relative increase in adipocity. Although in vitro studies suggest the existence of an age-related lineage switch between osteogenic and adipogenic fates, stem cell and microenvironmental contributions to this process have not been elucidated in vivo. In order to study the effects of MPC and microenvironmental aging on functional engraftment and lineage switching, transplantation studies were performed under non-myeloablative conditions in old recipients, with donor MPCs derived from young and old green fluorescent protein (GFP) transgenic mice. Robust engraftment by young MPCs or their progeny was observed in the marrow, bone-lining region and in the matrix of young recipients; however, significantly lower engraftment was seen at the same sites in old recipients transplanted with old MPCs. Differentiation of transplanted MPCs strongly favored adipogenesis over osteogenesis in old recipients irrespective of MPC donor age, suggesting that microenvironmental alterations that occur with in vivo aging are predominately responsible for MPC lineage switching. These data indicate that aging alters bone-fat reciprocity and differentiation of mesenchymal progenitors towards an adipogenic fate.
COMPARING INDICATORS OF HEALTH OR NUTRITIONAL STATUS

The performance of an indicator of health or nutritional status depends on its sensitivity and specificity properties over a range of cut-offs. Frequently, it is of interest to compare indicators to pick the best for a given purpose, such as screening for disease or monitoring to detect changes in prevalence of inadequate nutriture. Relative operating characteristic (ROC) analysis provides an objective method for making this comparison, but the application of this methodology as described for epidemiologists in this Journal is now outdated for most indicators. Recent developments are noted and an alternative analysis for use with continuous Gaussian data is presented here. The estimators and statistical test procedures proposed here are compared with the previously described methods, by means of a computer simulation study. The new procedures are found to be superior for continuous Gaussian data, and have the practical advantage that they do not require use of a specialized computer program. The implications of these results for comparing indicators to be used to monitor population prevalences are discussed.
Petrologic case for Eocene slab breakoff during the Indo-Asian collision: Comment and Reply REPLY

We thank [Chung et al. (2003)][1] for their comment, which permits further discussion of Indo-Asian tectonics. In our paper ([Kohn and Parkinson, 2002][2]), we presented three petrologic lines of evidence for slab breakoff, including (1) Himalayan eclogites, (2) partial melting of the Greater
The Biggest Little Contributions

At about 10 p.m. on the first day of October 1915, some 200 km west of Reno, Nevada, the U.S.A.’s Biggest Little City, and 100 km or so north of our nation’s Loneliest Highway, the sky was cold and moonless. And in this particular location of the arid and sparsely settled Basin and Range, as is generally the case, absolutely nothing happened. The next day was different though. It was then, only nine years after the great 1906 California earthquake, that Nevada’s contributions to earthquake science began. After a couple of quite strong earthquakes in the late afternoon, things had apparently quieted down sufficiently for the residents of the little mining community of Kennedy, adjacent to a little valley called Pleasant, to consider safely retiring for the night. It was not to be. At about 10:50 p.m., a yet more violent shaking occurred. Those present who had also been through the San Francisco earthquake of 1906 were of the general opinion that “the Kennedy shake was more violent than that one” (Berry, 1916, 52). It was a big one. Now, 101 years later, the Pleasant Valley earthquake has given Nevada’s Seismological Laboratory at the University of Nevada, Reno, reason to host the 2016 Annual Meeting of the Seismological Society of America in Reno, Nevada. > It was then, only nine years after the great 1906 California earthquake, that Nevada’s contributions to earthquake science began. The Pleasant Valley earthquake is generally assigned a magnitude of 7.2. It is not the only large earthquake to have occurred in Nevada. The 1932 Cedar Mountain and the 1954 Dixie Valley–Fairview Peak and Fallon–Stillwater earthquake sequences registered similar magnitudes (see Fig. 1). As a Biggest Little City resident, in a state commanding less than 1% of the nation’s population, I am led to suggest that these historical …
Attosecond control of electron emission from atoms and the relative phase of even and odd harmonics in an Attosecond Pulse Train

We demonstrate that electron emission from atoms can be controlled on an attosecond time scale, and that such emission provides information on the phase of consecutive odd and even harmonics in the attosecond pulse train.
Woodland Word Warrior: An Introduction to Gerald Vizenor with a Bibliography of His Work

One of the most prolific, contemporary American Indian authors, Gerald Vizenor (Ojibwe)1 was awarded the 1986 Fiction Collective/Illinois State University Prize for his Griever: An American Monkey King in China (1987). Despite his extensive publication and his growing recognition as a writer, Vizenor has received little critical attention thus far. To introduce readers to the range and variety of Vizenor's creative writing, this article will survey his work and examine his use of a variety of genres and recurrent themes.